\r\n\tNeural networks is a beautiful biologically-inspired programming paradigm which enables a computer to learn from observational data and deep learning is a powerful set of techniques for learning in artificial neural networks.One of key reasons that neural networks are wildly successful today, after enjoying comparatively little success since the 1980s, is that we have the computational resources to run much larger models today. One of the main insights of connection is that living beings become intelligent when many of their neurons work together; while an individual neuron or small collection of neurons is not particularly useful.
\r\n\r\n\tWith the advent of general purpose GPUs, faster network connectivity and better software infrastructure for distributed computing, the popularity of neural networks and deep learning is strongly increased. This trend is generally expected to continue faster in the future. This is because deep learning and neural networks have consistently improved in their ability to provide accurate recognition or prediction. Moreover, deep learning has consistently been applied with success to broader and broader sets of applications. Both neural networks and deep learning currently provide the best solutions to many problems in image recognition, speech recognition, natural language processing, financial data regression, weather forecast, and so on.
\r\n\r\n\t
\r\n\tThe aim of this book is to provide the reader with a comprehensive state-of-the-art in artificial neural networks, collecting many of the core concepts and cutting-edge application behind neural networks and deep learning.
Since the first implantation of a pacemaker (PM) was performed in 1958, this effective form of antibradycardia therapy has evolved in an amazing way. Besides ensuring the survival of patients with asystole or complete AV block who lack a sufficient intrinsic escape rhythm, today there is a wide range of further indications including advanced therapy strategies for pacing therapy. After it was shown that frequent right ventricular (RV) stimulation (especially in the RV apex (RVA)) can be associated with clinical deterioration in patients with implanted cardioverter-defibrillators (ICD) the avoidance of unnecessary RV pacing (RVP) has become one of the cornerstones of modern ICD- and PM-therapy.
With intact cardiac conduction, the physiological excitation of the ventricles occurs with high velocity (3-4m/s) via the His‐Purkinje‐system (HPS) nearly synchronously. This is the basis for an optimum hemodynamic contraction sequence in all heart chambers.
Similar to the excitation in a premature ventricular contraction (PVC) or following conduction through an antegrade conducting bypass tract, ectopic ventricular stimulation will result in a more or less non-physiologic activation and therefore non-physiologic contraction sequence of the ventricles. For example, the conduction after stimulation in the RV apex (RVA) will occur mostly in the working myocardium with a significantly lower velocity ≤1 m/s in an apico-basal direction from the RV via the interventricular septum to the left ventricle (LV). The exact individual sequence of excitation and contraction will be influenced by stimulus location, activation of parts of the specific conduction system and electroanatomical characteristics of the myocardium (fibrosis, scars). The dyssychronous contraction resulting from atypical excitation due to pacing can be compared to the situation in patients with conduction delay or block in the left Tawara-bundle (left bundle branch block (LBBB)).
At the start of systole (isovolumetric phase) the myocardial fibers near the RVA-pacing site will be the first ones to shorten, whereas the more remote left lateral ventricular areas will go into passive stretching, as they are lacking electrical excitation at this point. In the ejection phase the early activated areas will be able to contract only a little further, whereas the later activated areas will contract 1) delayed and 2) increased due to the previous stretching (Fig. 1 and 4).
a. Transthoracic echocardiogram (TTE, apical 4-chamber view (A4CH)); 2b. Tissue Doppler. There is preserved global systolic LV-function but longstanding left ventricular dyssynchrony (here resulting from LBBB) causes a typical hypertrophy of the left lateral wall compared to the interventricular septum. This is due to the delayed systolic LV lateral wall activation and the increased contraction after the preceding passive stretching. The different colors in the Tissue Doppler demonstrate the dyssynchronous wall motion.
a. TTE, m-mode, parasternal long axis (PLAX); 2b. Doppler at mitral inflow, A4CH. Demonstration of systolic contraction of the left posterolateral ventricular wall (LV-PLW) while there is already left ventricular filling. The time interval Δt 1 from the beginning of the QRS complex to the end of anterior movement of the LV-PLW (
The electromechanical dyssynchrony influences the diastole as well. Whereas the first activated areas of myocardium already enter the relaxation cycle, the delayed activated ones can still be in systolic contraction. This late systolic contraction delays the passive ventricular filling and thereby shortens the effective duration of diastole (Fig. 2) [1].
The delayed dyssynchronous activation of the ventricles with RV stimulation is visible in the ECG by a more or less deformed and widened QRS complex (Fig. 3).
Lead-ECG of VVI pacemaker stimulation in the right ventricular apex. The stimulated QRS complex is visibly widened, shows a negative deflection in the inferior leads (II, III, aVF) and LBBB-like deformation. Note the fall of aortic pressure with VVI stimulation here in a patient with sinus rhythm.
TTE, m-mode, PLAX. Demonstration of the different times for maximum systolic contraction of the interventricular septum and the LV posterolateral wall. The “septal to posterior wall motion delay” (SPWMD) is measured as 377 ms in this case. Values > 130 (140) ms are considered pathological.
Echocardiography allows excellent noninvasive estimation of global and regional electromechanical dyssynchrony and hemodynamic consequences. Examples are shown in Fig. 1, 2 as well as 4 and 5. For more detailed information further specialized reading is recommended [2-5].
Visible shift of the contraction phases of interventricular septum and lateral LV wall, color-m-mode (5a) and Tissue Doppler/ strain (5b).
The first evidence for clinically relevant negative effects of a high percentage of RV pacing was found interestingly in studies that were originally intended to show benefits of “physiologic” AV sequential DDD stimulation compared to VVI stimulation.
The original intention of the DAVID trial (Dual Chamber and VVI Implantable Defibrillator) was to show a survival benefit of dual chamber ICD systems compared to single chamber ICDs. Patients with an ejection fraction <40% and chronic heart failure were enrolled, who didn´t have an indication for antibradycardia stimulation. The study was stopped early after enrollment of 506 patients: the patients with the supposedly “physiological” AV sequential DDD pacing (at least 70/min) had a 1.61 increased risk for mortality or hospitalization because of new onset or deteriorated heart failure compared to patients with VVI backup stimulation (40/min) only [1,6,7]. The proportion of ventricular stimulation was 55.7% in the DDD group compared to 2.9% in the VVI patients.
In a sub-study of the MOST trial (Mode selection Trial) it was shown that patients with DDD(R) stimulation for sick sinus syndrome / sinus node dysfunction (SSS / SND) and normal QRS duration (<120 ms) had a significant increase of their risk for heart failure hospitalization (HFH) associated with an increase of cumulative percentage RVP (cum%RVP) up to 40% [1,8].
Interestingly the correlation between the percentage of RV stimulation and the risk for HFH was different for patients with DDDR versus VVIR stimulation.
After detailed review it seemed that the risk for HFH stayed nearly constant for percentages of VP >40% in the DDDR mode. It was therefore speculated that the risk of HFH in the DDDR mode would not increase with further increases in cum%RVP above 40%, but a further risk reduction to about 2% could be achieved with minimization of unnecessary RV pacing (VP <10%).
Overall the relative risk for hospitalization due to heart failure was always higher for VVIR patients compared to DDDR patients who had a comparable percentage of cumulative right ventricular stimulation.
Furthermore a linear relationship, between RV pacing and the incidence of atrial fibrillation (AF), was found up to a right ventricular stimulation percentage of 85% [8].
This observation was confirmed in a prospective randomized study including 177 patients with SSS, by demonstrating that AAIR stimulation was associated with a significantly lower incidence of AF compared to DDD stimulation with a short (≤150 ms) or a long (300 ms) AV interval [9]. Furthermore no significant changes were observed for left atrial (LA) or left ventricular diameters in the AAI(R) population, whereas in both DDD(R) groups the LA diameter increased significantly.
A sub-analysis of the MADIT II study (Multicenter automatic defibrillator trial II) was also able to show a clear correlation between more frequent RV stimulation and increasing morbidity and mortality for the included collective of ICD patients [10]. With increased RV stimulation the percentage of VT episodes was higher. If there was a cum%RVP of ≥50% a significant increase of the risk for HFH was observed (p<0.001).
Gardiwal et al. showed that apart from an LV ejection fraction (EF) <40% a cum%RVP >2% is an independent predictor for the occurrence of ventricular tachyarrhythmias, mortality and episodes of heart failure in ICD patients (who had predominantly secondary prophylactic ICD indications) [11].
Since the implementation of specific algorithms for avoidance of unnecessary RV stimulation in modern PM and ICD systems several studies have shown the clinical relevance and necessity of this approach. The details of these studies will be shown in the following sections respectively.
In patients with single SND and completely intact AV conduction, the implantation of an AAI(R) system theoretically appears to be the best form of pacemaker therapy especially considering the - here 100% - avoidance of RV stimulation [12]. It has to be emphasized, that this pacing modality is so far the only one with a prognostic benefit (overall and cardiovascular mortality of 225 PM patients with SND) that was proven in a study: in the DANISH trial the AAI(R) stimulated patients had a higher survival rate, less deaths due to heart failure (HF) and other cardiac causes, less AF and fewer thromboembolic complications compared to the group with VVI(R) stimulation [7,12-14].
Indication:
In principle all AAI systems can be indicated in single SND without evidence of impaired AV conduction or concern over development of AV block in the future.
The following conditions have to be present:
No AV block of any degree (including °1)
Narrow QRS complex
Antegrade 1:1 conduction / Wenckebach point >120 (130)/min
No need for any medication causing conduction delay
No carotid sinus syndrome
No loss of consciousness as primary indication for pacing therapy.
Patients with carotid sinus syndrome or vasovagal syncope are not suitable for AAI systems, because apart from the inhibition of the sinus node intermittent AV block is encountered. [14].
Whereas the overall percentage of AAI(R) pacemaker systems is about 9-10% in Scandinavian countries [1,7], atrial single-chamber pacemakers are only implanted in selected cases in other countries. The German PM register lists for the year 2009 a nearly constant low implantation rate of 0.5% AAI systems [15]. The reasoning behind it is, that relevant AV conduction disturbances are often not detectable or foreseeable at the time of implantation, however a later manifestation cannot be predicted or excluded for the individual patient. The incidence of new onset AV block is overall low and is reported to be approximately between 0.65% and 1.8% per year [1,12,16]. In studies on atrial pacing for SND a median annual incidence of third-degree AV block of 0.6% (0%-4.5%) with a total prevalence of 2.1% (0-11.9%) was revealed. Potential clinical manifestations include
Clinical symptoms due to AV block associated bradycardia, pauses or asystole, if there is no sufficient intrinsic escape rhythm. The incidence of syncope or near-syncope is high within the group of patients with onset of higher degree AV block.
AAI pacemaker syndrome with non-physiologic long intrinsic, hemodynamically unfavorable AV delay (Fig. 6)
The fixation of the atrial lead in the appendage usually provides a stable position and good results for sensing and pacing threshold. Relevant ventricular far field signals should be ruled out carefully. Alternatively septal atrial (active) lead placement in the area of Bachmann´s bundle (Fig. 7) can provide a more synchronous atrial activation resulting in a shorter P wave duration. There is some evidence that septal atrial pacing might have preventive effects on the incidence and progression of atrial fibrillation [51,52].
a. 12-lead stress test ECG: Unlike the normal physiologic response there can be a lack of shortening or even an increase of the intrinsic AV conduction delay during AAI stimulation with exercising in some patients with SND: the atrial stimulation can appear in extreme cases within the preceding systole (atrial stimulus shortly after or even within the QRS complex), the (nearly) simultaneous contraction of atria and ventricles can be the consequence, resulting in an AAI PM syndrome (6b).
Chest x ray. Single-chamber AAI PM implanted on the right side in a young female patient with symptomatic idiopathic sinus bradycardia. The active atrial electrode is placed at the septum, resulting in a narrow P wave indicating better synchronized activation of the atria.
If there is impaired AV conduction, a dual- or triple-chamber pacemaker system should be implanted. This should be considered in patients with advanced cardiac disease as well [14].
The indication for implantation of single-chamber AAI PM in patients with SND is currently questioned even more after the results of the DANPACE trial (The Danish multicenter randomised trial on AAIR versus DDDR pacing in sick sinus syndrome) [Nielsen, ESC Congress 2010]. The aim of this study was to compare AAIR with DDDR stimulation (lower rate 60/min, upper rate 130/min, paced/sensed AV‐interval ≤220 / ≤200 ms). As main finding there was no survival difference for the 1415 patients in the two groups after follow up over 5.4±2.6 years. The mortality of all causes was 29.6% in the AAIR group versus 27.3% in the DDDR group (p=0.53). There was a doubling of reoperation risk with AAIR pacing. After correction for baseline variables, the patients in the AAIR group had a 27% risk increase for the development of atrial fibrillation. This contradicts the results of previous studies and therefore was not expected. However there was no monitoring regarding atrial fibrillation before enrollment, which means that a preexisting difference between the groups in AF prevalence already at baseline cannot be excluded. Additionally, monitoring in the follow up was not very sensitive for recognizing of AF episodes. The conclusion of the DANPACE authors was, that single-chamber (AAIR) pacing should be avoided in patients with SND and that DDDR stimulation using an AV interval ≤220 ms should be the pacing modality of choice for SND.
In his guest editorial for PACE in 2001 S. Barold concluded that permanent single-chamber atrial pacing is
The guidelines of the German society of cardiology state that VVI stimulation with a low intervention rate (e.g. <45/min) can be indicated, if there is rare disturbance of AV conduction (occurrence <5%) [indication class I B]. [14,18,19].
Fröhlig justifies the indication for implantation of a simple „VVI backup“-PM system in patients with recurrent syncope due to paroxysmal AV block, BBB and normal HV interval [1]. These patients have a high risk for further syncopal episodes. If there is no need for antibradycardia pacing apart from the short phases of paroxysmal AV block, this subgroup can be fitted adequately with a sole VVI „backup“ stimulation of 40/min.
Compared to pacemaker patients the situation looks different in patients with an ICD indication only, without need for antibradycardia pacing. The above mentioned DAVID study showed superiority of single-chamber ICD systems with a programming of VVI 40/min to a dual-chamber mode [1,6,7].
In 2007 the INTRINSIC RV trial enrolling 988 ICD patients showed that the group with DDD pacing (60-130/min) with AV search hysteresis (AVSH, Boston Scientific) was not inferior to the VVI backup pacing group (40/min) in terms of all-cause mortality and heart failure hospitalization after 10 months follow up [20]. In the DDDR AVSH group the mean cum%RVP was 10% compared to 3% in the VVI pacing group. It has to be emphasized however, that prior to randomization only patients that had <20% ventricular stimulation in the first week after implantation in DDDR AV search hysteresis mode were selected and therefore would be regarded as likely “responders” to AVSH.
The MVP trial was a prospective, multicenter, randomized, single-blind, parallel, controlled clinical trial which didn`t succeed in showing that atrial-based dual-chamber managed ventricular pacing mode (MVP™) is equivalent or superior to backup only ventricular pacing (VVI 40/min) with regard to time to death, heart failure hospitalization and heart failure–related urgent care in patients with standard indication for ICD therapy and no indication for antibradycardia pacing. The overall HF event rate was found to be slightly higher during AAI pacing and was mainly seen in patients with a PR interval ≥230 ms in the MVP-60 group compared to VVI-40. There were no differences between the two compared ICD pacing modes for atrial fibrillation, ventricular tachyarrhythmias, quality of life, or echocardiographic measurements. [21].
There is an ongoing discussion with regard to a possible improvement of discrimination between supraventricular and ventricular tachyarrhythmias due to additional atrial information in dual-chamber ICD compared to VVI systems as this could avoid inadequate therapy deliveries by the ICD.
The DATAS trial found a reduction of clinically significant adverse events (CSAE) in dual-chamber ICD versus single-chamber devices or simulated single-chamber mode in implanted dual-chamber systems [22]. It was possible to reduce the occurrence of inadequate ICD shocks for atrial fibrillation in dual-chamber ICDs. Procedure related complications were more frequent with dual-chamber devices.
A meta-analysis from 2008 (748 patients) found less inappropriate treated episodes with dual-chamber discrimination but the number of patients experiencing inadequate therapies was not reduced [23]. It has to be known that the programmed criteria for differentiation of supraventricular and ventricular tachyarrythmias in the VVI ICD in this study were most commonly “onset” and “stability”. Modern single-chamber ICDs offer markedly improved discrimination algorithms as standard today.
In summary the majority of patients with ICD indication only, i.e. lacking foreseeable demand for antibradycardia pacing or indication for CRT at the time of implantation, can be fitted adequately with a modern VVI ICD system and a backup-rate of 30-40/min. Advantages include avoidance of unnecessary RV stimulation, less expensive and less complex systems, less complications at implantation and in the long term course by using just a single lead. Most of the time in current single-chamber ICDs using modern algorithms there isn´t worse SVT/VT discrimination compared to dual-chamber ICDs.
The disadvantage of this strategy is: If the need for regular antibradycardia pacing arises in the clinical course of patients with single-chamber ICDs the upgrade to a dual-chamber or CRT system is often a more complex procedure.
Therefore, dual‐chamber ICD systems should be preferred in the following situations (of course unnecessary RVP should still be avoided when possible):
Conventional PM indication (especially SND; with permanent AV block II º or IIIº consider CRT-system)
Long-QT-Syndrome
History of (frequent) atrial tachyarrhythmias.
Programming of a fixed long atrioventricular delay (AVD) supports intrinsic conduction in patients with largely intact or only mildly impaired atrial and atrioventricular conduction and thereby avoids unnecessary RV stimulation.
However, even in patients with isolated disease of the sinus node and a programmed fixed AVD of 300 ms, a percentage of >10% RV stimulation is found in about every third patient [1,24]. It has to be kept in mind that the IEGM determined AVD of the PM is not identical with the PQ interval measured in the surface ECG. The relevant AV interval for the timing of the PM in atrial stimulation consists of: conduction time from the stimulus to the atrium, intra- and interatrial conduction times, AV conduction and the time to the expected actual detection of ventricular activation, which sometimes can be markedly delayed up to the S wave of the chamber complex [25].
In clinical practice the following problems have to be considered with fixed long AVD programming [25]:
A prolonged AVD results in an extension of the total atrial refractory period (TARP, fig. 8). Depending on the programmed postventricular atrial refractory period (PVARP) a limitation of the upper rate behavior can be the consequence, i.e. respectively lower limitation of the upper 1:1 AV conduction rate (upper tracking rate, 2:1-block rate), which can lead to problems with higher degree AV block on exercising.
Example: with an AVD of 300 ms plus a PVARP of 300 ms, the PM is not able to detect atrial rates above 100/min 1:1 anymore and if there is a higher degree AV block to track AV sequentially 1:1.
TARP = AV Delay + PVARP
If as compensation the PVARP is programmed shorter in patients with preserved VA conduction, the occurrence of pacemaker mediated tachycardias (PMT) is facilitated.
With an extremely long AVD the frame for detection of intrinsic atrial activities is limited, which sometimes - depending on the postventricular atrial blanking period (PVAB) - can possibly lead to an impairment of the mode switch reaction in atrial tachyarryhthmias [26].
In case of higher degree AV block with resulting need of ventricular stimulation the (ultra-) long fixed AVD may result in a less favorable hemodynamic situation.
If there is intermittent atrial undersensing (typically in atrial fibrillation) a very long AVD may favor proarryhthmogenic pacemaker-induced R-on T-stimulation. To avoid this a short postatrial ventricular blanking period should be programmed and the ventricular safety stimulation (safety window pacing) should be activated [25].
With SND and preserved AV conduction DDIR mode is recommended if a long AV delay is programmed [25,27]. Unfortunately this is not really an option in patients with intermittent AV block, as intrinsic P waves (AS-events) can’t trigger AV sequential response then.
In summary the programming of fixed long AVD is associated with numerous problems. Nielsen et al. entitled a publication in 1999: “Programming a fixed long atrioventricular delay is not effective in preventing ventricular pacing in patients with sick sinus syndrome” [24]. For the effective avoidance of unnecessary RV stimulation the following modern algorithms should be preferred, if the implanted DDD PM offers these options.
To escape the problems associated with long fixed AVD the AV hysteresis was developed. The term “hysteresis” originates from the Greek
The algorithm distinguishes intact versus impaired / non-physiologically prolonged intrinsic AV conduction. A longer intrinsic AV conduction time is permitted ensuring stimulation with an optimized AV interval in case of a higher degree AV block.
Basically there are 2 sets of sensed or paced (AV / PV) atrioventricular intervals:
The shorter AV-/PV delay becomes active, if the conducted intrinsic ventricular sensed (VS) event is missing.
The longer (hysteresis) AVD will be switched to after VS events or when there is a search for intrinsic conduction [28].
The AV sequential cycle is mandatory for every beat.
If
AV hysteresis: 1. After ventricular sensing (VS) the short AVD is extended by the programmed hysteresis interval. 2. A ventricular stimulation (VP) after the active long AVD deactivates the hysteresis and stimulation continues with the programmed short AV/PV delay.
If an
The
AV search and repetitive hysteresis.
Generally in modern devices these 3 algorithms can be activated combined in 1 function. The exact criteria that can be programmed (maximum AV time extension, search intervals) vary between the device manufacturers and models.
As examples available algorithms of 4 manufacturers are explained:
AV search hysteresis (AVSH (+)), Boston Scientific
Example devices: INSIGNIA®, ALTRUA®, ADVANTIO, INGENIO
Programming options (depending on the model):
AV delay 10 (30) up to 300 respectively 400 ms in 10 ms steps (device dependent)
Dynamic AVD
Minimum (10 to 290 ms) and maximum AVD (20 to 300 respectively 400 ms; device dependent)
AV search interval (off, 32, 64, 128, 256, 512, 1024 cycles)
AV increase (proportional increase of AVD extension during one search cycle; 10% to 100%)
The AV delay will be extended periodically fixed or dynamical for up to 8 cycles to look for intrinsic conduction.
If the search was successful (ventricular sensing: VS), the extension will be continued, as long as there is intrinsic conduction (fig. 11). A switch back to the programmed AV / PVD is done after the first ventricular stimulus with long hysteresis AVD.
If the search is not successful, the stimulation continues with the programmed short AVD and a new AV search interval starts.
AVSH, BSCI. The tracing begins with AV sequential ventricular stimulation (AS/VP) with a programmed AVD of 125 ms. The extension of the AVD by the AV search hysteresis results in intrinsic conduction: AS/VS with an intrinsic AV interval of 178 ms.
AutoIntrinsic Conduction Search™ (AICS), St. Jude Medical
Example device: INTEGRITY [53]
With ventricular stimulation the function extends the AV / PVD every 5 minutes with a programmable hysteresis time (in ms) to search for intrinsic conduction.
On ventricular sensing the extension of the AV / PVD is set, a switch back is done after the first ventricular stimulus.
The maximum AVD is 350 ms.
The function becomes inactive in the following situations:
DDD(R) or VDD(R) mode + base rate ≥90/min + active rate dependent AVD
Intrinsic atrial rate or sensor rate ≥90/min
During rate search hysteresis.
Intrinsic Rhythm Support (IRSplus), Biotronik
Example device: Philos II DR.
When the IRSplus is activated, the following features are set:
AV hysteresis is at a fixed length of 300 ms. The long AV interval stays active if an intrinsic ventricular signal is sensed (VS).
In AV repetitive hysteresis there are five cycles with the prolonged AV / PV interval after a VS event has occurred. The AV hysteresis remains active, if intrinsic ventricular activity is sensed during one of these five cycles. However after five repetitive cycles without spontaneous AV conduction the device changes back to the short AV / PV interval.
In AV scan hysteresis there is extension of the AV delay for five cycles after 180 consecutive ventricular paced cycles. If in these five cycles a spontaneous AV conduction is detected, the AV hysteresis stays active. If no ventricular event has been detected within these five cycles the device switches back to the short AV delay interval and the cycles end with ventricular stimulation. The cycle counter is reset and commences counting the consecutive paced cycles.
Search AV/Search AV+, Medtronic
Example devices: Kappa 700 DR, EnPulseTM\n\t\t\t\t\t\t
The PM will try to detect intrinsic conducted events in an “AV delay window” that precedes scheduled VP events by -55 to -15 ms.
If the device classifies 8 out of 16 AV conduction sequences as too long /”late” (≤15 ms before scheduled VP), it prolongs the operating SAV and PAV intervals by 31 / 62 ms for the next 16 pacing cycles to facilitate intrinsic conduction until the maximum AVD. If the previous 8/16 AV intervals are defined as too short (>55 ms before scheduled VP), the device will shorten the operating SAV and PAV intervals by 8 ms for the next 16 pacing cycles.
In the case of inadequate AV conduction (8/16 VP with maximum AVD) the search will be repeated after 15 and 30 minutes and then after 1, 2 … 16 hours. The algorithm is deactivated after 10 unsuccessful searching attempts / 16 hours until the next device interrogation.
With the help of this algorithm intrinsic conduction is promoted even in cases with slightly changing AV conduction times and unnecessary long AV delay intervals are avoided.
The maximum AVD is 350 (
Melzer et al. compared the above mentioned algorithms Search AV (max. AVD sensed 230 / paced 260 ms) versus Search AV+ (max. AVD 300 / 360 ms) in a randomized study with 30 PM patients [29]. They showed that prolonging the AV interval above 300 ms results in an additional significant reduction of the percentage of ventricular stimulation (19±28% versus 70±40%, p<0.001).
A larger prospective non randomized multi‐center study enrolling 197 patients with a dual-chamber PM (EnPulse) demonstrated a reduction of cum%RVP from 97.2% without AV interval extension to 23.1% with Search AV+ [30]. There were no adverse events reported under Search AV+.
This strategy is currently considered the most effective form of reducing unnecessary RV stimulation. A dual-chamber system (PM or ICD) is implanted in the usual way with conventional atrial and ventricular leads. The programming follows a special AAI(R) mode, by which the device controls AV conduction with every beat. If intrinsic conduction is preserved, the stimulation will be in a functional AAI(R) mode. However, as the algorithm still maintains ventricular sensing to assess AV conduction, it acts technically like ADI(R) mode. In contrast to conventional dual-chamber systems with e.g. AV hysteresis these devices are allowed to accept even single non conducted p waves, e.g. as in second-degree AV block type Wenckebach (fig. 12).
A dual-chamber PM with AAIDDD mode switch (Reply DR,
If a higher degree AV block occurs the device switches automatically to a dual-chamber mode according to defined criteria and keeps this up until improvement of intrinsic conduction.
This strategy thereby is thought to combine the advantages of the AAI(R) mode in avoiding unnecessary RV stimulation with the safety of DDD(R) backup.
To show examples 4 currently available systems will be explained.
AAISafeR, AAISafeR2, ELA Medical, Sorin Group
Example devices: Symphony DR, Reply DR.
AAISafeR™: loss of sufficient intrinsic AV conduction:
The switch to dual-chamber mode occurs following a defined pattern, by which the AV conduction is classified:
7 consecutive AV / PV intervals, that are too long (programmable for rest and exercise “first-degree AV block” criterion, fig. 13)
3 AS / AP events without VS within the last 12 atrial cycles (“second-degree AV block” criterion, fig. 14,15)
2 consecutive AS / AP without VS (“high degree AV block” criterion, fig. 16)
Ventricular pause >2 up to 4 sec. (length of pause programmable, fig. 20)
AAISafeR2, Reply DR: pacing mode switch with consecutive long stimulated AVD.
AAISafeR2, Reply DR: mode switch after 3 of 12 consecutive sensed or stimulated atrial events without VS. (In this particular case the pacing mode switch is triggered by a frequency-dependent AV block caused by a short run of an atrial tachycardia, atrial CL about 450 ms).
AAISafeR2, Reply DR, Holter-monitoring: switch from AAI(R) to DDD(R) after 3 (in this case stimulated) atrial events without intrinsic conduction within the last 12 AA intervals.
AAISafeR2, Reply DR: paroxysmal AV block, possibly phase 4 block caused by critical prolongation of the PP interval after a conducted atrial premature beat (“Ar”). Switch from AAI to DDD after 2 consecutive atrial stimulated events (AP) without intrinsic conduction.
AAISafeR: Recurrence of sufficient intrinsic AV conduction
After 100 ventricular stimulations (VP) the device checks intrinsic AV conduction (fig. 17, 18, 20). A switch back from DDD(R) to AAI(R) takes place after 12 cycles of spontaneous conduction.
AAISafeR2: After unsuccessful search for sufficient intrinsic conduction DDD(R) stimulation is continued.
AAISafeR2, Symphony DR: Successful mode switch from AV sequential DDD pacing with ventricular fusion to AAI mode resulting in intrinsic AV conduction (APace/VSense).
In contrast to MVP® the AAISafeR is programmed for a permanent switch to DDD(R) mode in case of persisting AV conduction disturbance:
If there are ≥15 mode switches within 24 hours
If there are >5 mode switches per day on 3 consecutive days
A specific feature is the pacing mode switch when there is sensing of a ventricular event within the committed interval (ventricle, 94 ms after atrial stimulation: Vr). Whereas in the DDD mode after the Vr event a ventricular safety stimulation occurs, the SafeR mode is not counting a sensed Vr as conducted in this committed interval. This can lead to a switch from AAI(R) to DDD(R) (fig. 19)
AAISafeR2, Reply DR: With AAISafeR mode the occurrence of 2 consecutive ventricular events within the committed interval (Vr) results in mode switch to DDD. Once in DDD mode a safety stimulus is delivered here (Vn).
The efficiency of the AAISafeR algorithm was shown in an approval study enrolling 43 patients with SSS and intermittent AV block: after 1 month 65% of the patients remained in AAI(R) mode with a ventricular stimulation percentage of only 0.2±0.4%, in 35% of the patients the device automatically changed to permanent DDD(R) mode due to frequent mode switches (73±23% VP) [1,7,31,32].
AAISafeR2 offers the following modifications [33]:
The amount of time with stimulation in dual-chamber mode (>50%) is used as a criterion for a persisting impairment of AV conduction.
If there is AV block with an exercise induced heart rate >100 this is not used as criterion for “persisting AV conduction impairment”.
The switch criterion “too long consecutive AV intervals” can be inactivated for resting.
Even after switch to DDD(R) with persisting AV block the device runs a search for intrinsic conduction every morning (fig. 20).
Fröhlig et al. investigated the algorithm in 123 PM patients with SND, paroxysmal AV block or Bradycardia Tachycardia Syndrome (BTS). In 97/123 patients an adequate switch to DDD was seen, with 69 patients (56%) this wasn´t persisting, average %VP was 0.2±0.5% [33].
AAISafeR2, Reply: Unsuccessful search for intrinsic conduction in a patient with third-degree AV block, resulting in a long pause > 3 sec. DDD mode is maintained.
The majority of publications about AAISafeR2 didn´t report any adverse events [32-35].
Thibault et al. observed 2 SafeR related adverse events among 208 PM patients:
1 patient with SND and second-degree AV block complained of dizziness. 24-hour electrocardiogram revealed ventricular pauses as cause, another patient with SND and first-degree AV block presented with unexplained syncope. In both of these cases the device was reprogrammed to DDD [36].
Ventricular pace suppression (Vp Suppression®), Biotronik.
Example devices: Evia / Entovis, Estella series
Depending on evaluation of intrinsic AV conduction the device works either in DDD(R) or ADI(R) mode. Independent of that the system offers a mode switch to DDI(R) for atrial tachyarrhythmias (fig. 21).
Stimulation forms of the Vp Suppression® algorithm, Biotronik
Vp Suppression®: DDD(R) mode
With Vp Suppression® activated the system stimulates first in the DDD(R)-mode with a programmed AVD. A VS search is started after a VS event or if there is no intrinsic conduction within 0.5 min. AVD is then extended to 450 ms to search over 8 cycles for intrinsic conduction. The device switches to ADI(R), if the programmable criterion “x consecutive VS” is met. It is possible to program 1, 2…8 consecutive VS events in individual steps, default 6. If the criterion isn´t met within the VS search period, the device continues to work in the DDD(R) mode with the programmed AVD and the searching interval is doubled up to maximum of 128 min. Thereafter the next search is initiated every 20 h, as long as Vp Suppression® is activated.
Vp Suppression®: ADI(R) mode
A cycle without intrinsic conduction / VS within 450 ms triggers an observation period of 8 repetitive cycles, to make the decision about switching back to DDD(R) mode according to the following criteria:
x/8 cycles without VS (programmable)
2 consecutive cycles without VS
No VS for at least 2 sec.
RYTHMIQ, Boston Scientific
Example devices: ADVANTIO, INGENIO, ENERGEN, INCEPTA
The algorithm is automatically activated, if the indication-based programming (IBP) is used.
RYTHMIQ: Intact intrinsic AV conduction
If there is preserved intrinsic AV conduction, the system works in the AAI(R) mode at the lower rate limit (LRL) or sensor rate (SIR) with backup VVI stimulation at a rate which is 15/min below the programmed LRL [37]. The VVI backup can be provided between a rate not slower than 30/min but not faster than 60/min. During AAI(R) mode the device continuously checks AV synchrony.
RYTHMIQ: Loss of sufficient intrinsic AV conduction
The device automatically switches to DDD(R) mode, if three blocked or “slow ventricular beats” are documented within a rolling detection window of 11 beats. RYTHMIQ defines a “slow ventricular beat” as a ventricular event (VS or VP) occurring at least 150 ms slower than the atrial pacing rate (LRL or SIR) [37].
RYTHMIQ: Reoccurrence of sufficient intrinsic AV conduction
From DDD(R) mode a regular search for intrinsic conduction is carried out by using the AV Search+ algorithm. The pacing mode is switched back to AAI(R) with VVI backup, if AV Search+ 1) can remain in AV hysteresis for a minimum of 25 intervals and 2) less than two out of the last ten cycles are VP events [37].
RYTHMIQ: Mode switch for atrial tachyarrhythmias
The algorithm is able to detect atrial tachyarrhythmias from either AAI(R) with VVI backup or DDD(R). In the case of detection of atrial tachyarrhythmias the system immediately changes to the ATR mode switch.
Managed Ventricular Pacing® (MVP®), Medtronic
Example devices: Adapta L ADDRL, Ensura DR MRI, Protecta DR.
MVP®: Intact intrinsic AV conduction [38]
The device works in the AAI(R) mode with programming and timing for atrial single-chamber stimulation. At the same time there is active surveillance of AV conduction.
The atrial refractory period (ARP) cannot be programmed. It is set to 600 ms for rates <75/min respectively 75% of ventricular cycle length (CL) for rates ≥75/min. This dynamic ARP is intended to stop unnecessary switch episodes with singular non conducted atrial extra beats (PAC) or R wave far-field sensing.
If there are fast intrinsic ventricular events (e.g. PVC, VT) the atrial stimulation is inhibited. This is done to avoid unnecessary atrial stimulation, if the intrinsic ventricular rate is higher than the stimulation rate. Additionally the recognition of tachyarrhythmias is facilitated, if there is no interference by the blanking periods after atrial stimulation.
a. MVP® (EnTrust): Switch from AAI(R) to DDD(R) after intrinsic AV conduction was missing during 2 of the last 4 AA intervals. Special attention has to be paid to the fact, that the ventricular backup stimulation fires 80 ms after the intended (actually given or inhibited!) atrial stimulus after each AA interval without ventricular sensing (VS). (This ECG was sent to us per emergency fax as suspected ICD dysfunction: the specifics of AAI DDD mode switch can lead to substantial uncertainties). b. MVP® (Protecta DR): Switch from AAI(R) to DDD(R) due to sudden second-degree AV block with 2:1 AV conduction.
MVP® (Adapta DR): Action of the algorithm in a patient with second-degree AV block type Wenckebach. After there is a consecutive prolongation of the intrinsic AV conduction time (AP/VS) a singular AV conduction is missing and after the next stimulated atrial beat a ventricular stimulus is given.
The AAI(R) mode is maintained as long as intrinsic AV conduction is present. The criterion of intact intrinsic AV conduction is considered to be met, if there is a sensed ventricular event detected before the next atrial sensed event (AS) or atrial stimulation (AP).
The programmed AVD (PAV / SAV) is not relevant in this mode and will be only active after switch to DDD(R) mode.
MVP®: loss of sufficient intrinsic AV conduction
The device switches automatically to a temporary DDD(R) mode, if there was no intrinsic ventricular event (VS) during 2 of the last 4 atrial intervals. After a missing VS event, there will be a ventricular backup stimulation following the next atrial action (fig. 22). If the following atrial event is not conducted either, the device switches to DDD(R) mode. Thereby singular missing VS events are tolerated (fig. 23). Two consecutive missing ventricular events however are not permitted. This behavior can cause pauses with duration of twice the cycle length of the intervention rate before switch to DDD(R), if there is a sudden loss of intrinsic AV conduction (fig. 24).
MVP® (Adapta DR): basic rate 50/min (1200 ms). When AV conduction is lost, a ventricular backup stimulus is given, but not with the normal AV time after the 2nd blocked P wave, but 80 ms after the next intended (here inhibited!) atrial stimulus. The “pause” between the first blocked P wave and the ventricular backup-stimulus is here 1280 ms. Because the following intrinsic AV conduction was intact again, the device stayed in the AAI(R) mode.
a. MVP® (Protecta DR): Successful test for intrinsic AV conduction, switch from DDD (AS/VP, ventricular fusion) to AAI (AS/VS). b. MVP®: Negative test for intrinsic AV conduction in a patient with third-degree AV block.
There is no automatic switch over to a permanent DDD(R) mode.
MVP®: Reoccurrence of sufficient intrinsic AV conduction
After switching to DDD(R), the device checks the intrinsic conduction in regular intervals and thereby checks the possibility for return to AAI(R). This starts already one minute after change to DDD(R) with a switch to AAI(R) for one cycle.
If there is a VS event following the next AA interval, the device remains in AAI(R) (fig 25a).
If there is no VS event following the next AA interval, the conduction test was negative and the device remains in DDD(R) (fig. 25b).
After each negative test the time interval doubles to the next control (1 => 2 => 4 => 8 =>…min). The maximum time interval is 16 hours.
As a consequence of this periodic check, patients with permanent complete AV block will have a single missing ventricular beat every 16 hours.
MVP®: Mode switch for atrial tachyarrhythmias
The device switches to DDIR both from AAI(R) and DDD(R) on the onset of an atrial tachyarrhythmia to avoid fast atrial 1:1 triggering. The mode switch to DDIR for atrial tachyarrhythmias is given a higher priority than MVP®. Once the termination of the atrial tachyarrhythmia is recognized, there is a change to DDD(R) no matter which mode was active before that episode. Then an AV conduction test (1 beat) is performed and the device returns to functional AAI(R), if AV conduction is verified. If not, the DDD(R) mode is maintained and regular conduction tests are carried out (1, 2, 4, 8 min … 16 h), as described above.
The MVP® algorithm is highly effective in avoiding unnecessary RV stimulation.
In a randomized pilot study including 30 patients with dual-chamber ICDs without history of AV block MVP® “dramatically” reduced cum%RVP from 80.6±33.8% to 3.79±16.3% (p<0.0001) [39]. 15% of AV intervals under MVP® were longer than 300 ms. There were no relevant symptoms or adverse effects with MVP®.
In 181 ICD patients, that were randomized in a prospective manner, a 99% relative reduction of the cumulative ventricular pacing percentage (cum%VP 4.1±16.3 vs. 73.8±32.5, p<0.0001) by application of the MVP®-algorithm versus DDD(R) was found, again without adverse events [40].
In principle it is possible to reduce cum%RVP in all patients with SND and intermittent impairment of AV conduction. According to an investigation by Gillis et al. the reduction of ventricular stimulation percentage is higher in PM patients with SND than in patients with AV block (median relative reduction 99.1% vs. 60.1%) [41]. In a mixed PM population it was possible to reduce cum%VP to ≤40% with the MVP® algorithm in 72% of patients [42]. Compared to AV search hysteresis Search AV+ there was a significantly lower median percent VP by application of MVP® with the exception of the patients with persisting third-degree AV block [43]. Of the 322 PM patients in this study the best VP reduction was found in mildly impaired AV conduction.
The safe and effective use of MVP® was shown for pediatric patients and grown up patients with congenital heart disease as well [44]. In this study it was necessary to change the programming to DDD in one case of symptomatic intermittent AV block.
The (hemodynamically) optimal form of stimulation for patients with a long AV conduction time (“long AV-block °1”) remains still unclear and has to be tested in the individual patient. Especially for these patients one has to consider that MVP® depending on the intervention rate will tolerate any length of AV conduction time, as long as there is a ventricular sensed event (VS) before the next atrial sensing (AS) or atrial stimulation (AP). This can lead to hemodynamically unfavorable (ultra-) long intrinsic AV times (Fig. 6). In this clinical scenario permanent DDD(R) stimulation with a fixed AV delay optimized e.g. by echocardiography may be more favorable [45].
As already mentioned before, the effective ventricular rate can drop to half of the intervention rate before switch to DDD(R), if there is a sudden loss of intrinsic conduction. Therefore it is recommended to program the basic rate of patients with sinus bradycardia or frequent AV block to a minimum of 50/min.
When the available literature is reviewed, only few cases concerning clinical problems with MVP® are to be found. Mostly the algorithm worked as specified; the most common findings were:
Atrial events, in which functional undersensing occurred due to the long atrial refractory period (Fig. 26)\n\t\t\t\t\t\t
Ventricular events, in which functional undersensing occurred during the ventricular blanking time following the next atrial stimulation
Major variations in AV delays
Ultra long AV delays being accepted with the result of short VA intervals
Long atrial pauses
Occurrence of unnecessary RV pacing because of “linking”, i.e. repetitive retrograde invasion of ventricular depolarization into the AV junction resulting in non-conducted P waves
MVP®, EnRhythm DR: Functional undersensing of atrial events due to the long atrial refractory period in a patient with a fast atrial rhythm (sinus or atrial tachycardia), CL about 480 ms.
Murakami et al. reported 2 out of 127 Patients suffering from chest discomfort and one case with mild dizziness due to 2nd or 3rd degree AV block with frequent non-conducted atrial events in MVP mode [46]
A serious potentially proarrhythmogenic effect of MVP was observed by van Mechelen and Schoonderwoerd. In a patient with implanted PM for complete AV block a polymorphic VT degenerated to ventricular fibrillation which was successfully terminated by external defibrillation. Pacemaker interrogation showed correct device function in AAI mode (MVP) before the VT episode with irregular ventricular events (slow escape rhythm with frequent PVCs) and no AV synchronicity. The slow ventricular escape rhythm together with short coupled PVCs constituted proarrhythmogenic short-long-short cycles. Combined with documented hypokalemia, this caused the VT. As a consequence the MVP algorithm was switched off [47].
Clinical Benefit of Ventricular Pacing Reduction by AAI(R)DDD(R) mode switch
Meanwhile, first study results became available showing the clinical benefit of reducing unnecessary RV-stimulation by AAI(R)DDD(R) mode switch algorithms.
In the SAVE PACe trial patients with symptomatic bradycardia due to sinus node disease were evaluated for the primary endpoint “time to persistent atrial fibrillation” [48]. Excluded were patients with persistent atrial fibrillation or cardioversion for atrial fibrillation in the preceding 6 months, second- or third-degree AV block and wide QRS complex. The 1065 enrolled pacemaker patients were randomized to either DDD(R) pacing mode (AVD 120 to 180 ms) or to a dual-chamber pacing mode with a minimal ventricular pacing algorithm (MVP or SAV+). The study was stopped when in the interims analysis the pre-specified efficacy boundary (P=0.007) for difference in persistent atrial fibrillation between the two groups was reached (after 1.7 + 1.0 years). The difference in the median cum%RVP was substantial: 99 % in the DDD group vs. 9.1 % in the MVP group (P<0.001). The reduction of the risk for development of persistent atrial fibrillation was significant: 40% relative risk reduction (P=0.009) and 4.8% absolute risk reduction in the SAV+/MVP group. As clinical outcome there was a trend towards more strokes in patients who developed persistent atrial fibrillation, compared to those who did not (n.s., P=0.18). There was no significant difference for mortality between the two groups. The conclusion of the authors was that in their examined group of patients with SND dual-chamber pacing with the use of a minimal ventricular pacing feature (MVP or SAV+) prevents ventricular desynchronization and is of advantage in reducing risk of persistent atrial fibrillation.
A single center randomized clinical trial done by Xue-Jun et al. compared follow up results after 3 months of pacing in DDD mode (AV delay 250 ms with 30 ms extension) with AAISafeR mode. 30 patients with sick sinus syndrome were randomized to one of the two modes for 3 months and then switched over to the other mode for another 3 months. After 3 months in DDD mode echocardiographic analysis showed that left atrial diameter, left ventricular end-diastolic diameter and left ventricular end-systolic diameter had increased significantly and left ventricular ejection fraction had decreased. However after 3 months of pacing in the AAISafeR mode no obvious changes were noted. In the AAISafeR mode cum%RVP was significantly reduced compared to the DDD mode. The authors of this randomized trial using echocardiographic follow up concluded that AAISafeR mode is not only effective in reducing the amount of unnecessary RV pacing in sick sinus syndrome substantially, but also prevents harmful effects on cardiac performance [49].
Recently the importance of reducing unnecessary RV stimulation has been recognized widely. This is reflected in the ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities, which for the first time includes a separate chapter regarding this topic (“Importance of Minimizing Unnecessary Ventricular Pacing”) [50].
Today we have several options available for this task. Which one to use has to be considered individually for each patient with an indication for a device - at the time of implantation and during follow-up.
The use of atrial single-chamber systems will stay limited to singular cases even in patients with SND, because of the missing ventricular backup if impairment of AV conduction occurs. Apart from the indication for bradycardia in permanent atrial fibrillation, single-chamber VVI PM systems as “backup” can be used as an option for patients with rare paroxysmal AV block. The other major application of single-chamber VVI backup devices with low intervention rate is in ICD therapy, if there is no need for concomitant antibradycardia pacing.
In dual-chamber systems the programming of a fixed long AVD offers a “makeshift-programming”, if there is no other specific algorithm available. AV search hysteresis permits markedly longer intrinsic AV conduction times with stimulation with optimized AV interval in the event of higher degree AV block. An effective reduction of unnecessary RV stimulation is possible with the new AAIDDD mode switch algorithms. The clinical effects of wider use of these new functions need to be further evaluated in ongoing trials.
World’s 80% population resides in the developing countries, but these consume only 40% of the total energy consumption. Per capita energy consumption gauges the prosperity and economic growth of any country. The significant energy demand of the world is fulfilled by the petroleum sources. The fuel consumption region wise is shown in Figure 1 for the year 2017–2018. It is seen that Asia is the leading consumer of coal, oil, hydroelectricity, and renewable power. North America leads in consuming natural gas and nuclear energy. Asia’s consumption of coal is nearly 74.5% of the world coal consumption [1]. The fast depletion of petroleum resources is a major concern for the economic development of many countries. Therefore, the energy crisis is debated on all forums, and evolution from conventional to sustainable energy sources has become very relevant to maintain the momentum of economic growth. Renewable sources of energy can provide the energy sustainably and without harming the environment. Figure 2 shows the broad classification of renewable energy sources.
\nFuel consumption (in percentage) region wise for the year 2017 [
Classification of energy by source type [
Biofuels are the most effective and efficient form of renewable energy. They can be easily extracted from the biomass, and they are biodegradable and are environment-friendly [3]. Their combustion is almost similar to fossil fuels [4], and they produce less toxic compounds [5, 6]. The biomass absorbs carbon dioxide from the atmosphere, and when they are used as energy source, they release the carbon dioxide back into the atmosphere. However, the amount of carbon dioxide released into the atmosphere is less than that absorbed by the biomass [7]. The biofuels’ production of the world increased by 3.5% in 2017, shown in Figure 3. The United States alone provided the largest increment of 950 ktoe. Ethanol production grew at the rate of 3.3% and contributed over 60% of the total biofuels’ growth. Biodiesel production also rose by 4% on the account of growth in Argentina, Brazil, and Spain [1]. Several alternatives in diesel engines are available and can be used with minor or no modification. The advantages of these fuels include lower emissions, and since most of them are derived from renewable biomass sources, it will decrease the dependency on nonrenewable petroleum. The most potential fuel either to supplement or to substitute diesel is biodiesel, butanol, producer gas, dimethyl ether, hydrogen, and so on.
\nWorld biofuels’ production (million tons of oil equivalent).
Biodiesel appears more attractive for many factors because it is nontoxic and biodegradable. It is the substitution of petroleum diesel for either power generation or motive power without major modification. Furthermore, it releases significantly low aromatic compounds, sulfates, and chemical matters that pollute the atmosphere. Emissions of carbon dioxide are relatively low when the life cycle analysis is considered. Presently, biodiesel has been utilized throughout the world such as the United States, Brazil, Germany, Indonesia, Italy, France, Malaysia, and European countries. Consequently, there is a great prospect for its production and utilization. As of now, annual biodiesel production in the world is around 28 billion liters [1].
\nOver 350 oil-bearing crops were identified worldwide, which are appropriate for the production of biodiesel. Biodiesel feedstocks are regionally diversified [8]. It mainly depends on the soil conditions, climate, methods of cultivation and harvesting, and geographical locations of the country [9, 10]. The availability of potential feedstock plays a major role, which contributes to nearly 75% of the total cost of biodiesel [11, 12]. Therefore, it is very important to select an economical feedstock for improving the economics of biodiesel production.
\nApart from that, the percentage of oil in the feedstock and the yield per hectare are also significant factors. Several edible oil resources namely sunflower, rice bran, palm oil, rapeseed, soybean, peanut, and coconut are considered the first-generation feedstock of biodiesel. However, food versus fuel is a major concern for the researchers. Also, it is felt that plantation of feedstocks for biodiesel may require deforestation, reduction in available cultivatable land, and damage to soil resources. Moreover, the raw vegetable oil cost has seen a steep rise in the last decade that has changed the cost-effectiveness of biodiesel production [13, 14]. Furthermore, a number of countries are unable to cope with the growing gap between their demand and supply, which has created a challenge for them to produce cost-effective biodiesel from edible oil resources.
\nSeveral nonedible oils, waste oils, greases, and animal fats are considered as the second-generation biodiesel feedstocks [15]. Despite a large list of feedstocks of the second generation, it was believed that these might not be sufficient to fulfill the energy requirements. Moreover, animal fats and saturated fats have under-performed in low-temperature regions [16]. Collection mechanism of waste cooking oil [17] is tough because of its scattered sources, and there is always a problem of contamination with foreign particles [11, 16].
\nNumerous new researches are carried out nowadays to highlight the limitations of edible oils and the advantages of nonedible oils as a biodiesel feedstock. Nonedible oils for producing biodiesel can help in providing the key to tackle the problems of harmful emissions, cost-effectiveness, and the never-ending debate of food versus fuel [18]. Moreover, the plants used to produce seeds for nonedible oils can be cultivated on marginal lands, which can be degraded forests, arid lands, vacant lands, along highways, railways, and irrigation waterways and poverty-stricken areas. Various rural and low-income communities can take advantage of adopting the methods of production of biodiesel from nonedible sources to empower them. They also help in providing energy security and self-reliance. Nonedible feedstocks of biodiesel being sustainable shall be very advantageous as a substitute for diesel [11, 19].
\nBiodiesel or similar fuels can be produced by various methods such as pyrolysis, blending with other fuels, forming microemulsions and transesterification. These methods are briefly discussed later.
\nPyrolysis is carried out at high temperatures in the presence of catalyst and the absence of oxygen for decomposing the organic matters. The materials that are normally used for pyrolysis are oils derived from seeds, methyl esters of fatty acids, and animal fats. Several investigations were carried out in the past to obtain a diesel substitute by pyrolysis. Aromatics, alkanes, carboxylic acids, alkenes, alkadienes, and small quantities of gaseous products are produced by pyrolysis [20]. When compared to diesel, the fats and oils that have been pyrolyzed have a lower pour point, flash point, viscosity, and comparable calorific values. Other benefits of pyrolyzed vegetable oils include acceptable levels of copper corrosion values, sulfur, and water content. However, lower cetane number, ash, and carbon residual make their usage in diesel engine challenging [21]. It is worthwhile to mention that the pyrolysis process is a good alternative to diesel because of its simplicity, effectiveness, and pollution-free nature [15, 22].
\nTo make vegetable oil suitable for usage in a diesel engine, they are normally blended or simply diluted with diesel. The main benefit of blending is a reduction in viscosity of the blend and also improves the overall performance of the engine [23]. Hundred percent vegetable oil can be used in a diesel engine, but it gives rise to certain new challenges, which question its practical use on a long run [14, 24, 25]. Therefore, vegetable oil/diesel blends up to 25% shall be one of the choices for diesel engine [14, 24, 25]. However, the usage of vegetable oil and diesel blends in engines also brings some unwanted problems that need to be addressed thoroughly.
\nDimensions of a colloidal dispersion of optically isotropic fluid fall in the range of 1–150 nm that forms a microemulsion. It consists of one and more ionic amphiphiles and two immiscible liquids. Microemulsion of vegetable oils can be formed with alcohols, surfactant, cetane improver, or with an ester and dispersant (cosolvent) [22]. Microemulsion is beneficial due to their viscosity being similar to diesel. It has been observed that for both microemulsions (ionic and nonionic), the short-term performances are nearly equal to diesel [14, 24, 25, 26].
\nTransesterification also known as alcoholysis is one of the most popular, cost-effective, and simple chemical processes of conversion of high viscosity vegetable oils to a very low viscosity substance known as biodiesel. In transesterification process, 1 mole of vegetable oil and 3 moles of alcohol are allowed to react in the presence of a catalyst to produce 3 moles of alkyl ester and 1 mole of glycerine [27]. The triglycerides are first converted into diglycerides, which are further converted to monoglyceride and finally to glycerol. The products thus formed can be separated into two layers on its own by gravity. Biodiesel floats in the upper region, and glycerol settles at the bottom. In the cosmetic industry, glycerol is used extensively. Methanol and ethanol being economical are used commonly in the transesterification process. However, various higher chain alcohols namely propanol, butanol, and octanol could also be used for the production of biodiesel.
\nTransesterification process can be carried out by catalytic and noncatalytic methods. In the catalytic method, the catalyst is added to alcohols to increase its solubility, which enhances the reaction rate. Catalytic transesterification can be processed by an alkaline or an acid catalyst. Use of an alkaline catalyst is preferred because of its fast reaction, high yield, and economical nature. It is commonly seen that alkaline catalyst gives 4000 times faster reactions than acid catalyst [28, 29]. Alkaline catalyst namely sodium hydroxide, potassium hydroxide, potassium methoxide, and sodium methoxide are extensively used. Despite the higher cost of potassium and sodium hydroxide, they are most preferred due to their higher yields.
\nAlkaline catalysts are normally employed when the free fatty acid (FFA) level of the oil or fat is lower than 3%. Beyond this limit, the reaction proceeds with difficulty and challenges such as soap formation and reduced ester yields [30]. Some other limitations of the alkaline catalytic process include higher energy for production of biodiesel, difficulty in removal of unused catalyst from the final product, difficulty in glycerol recovery, and wastage of water during washing [10, 31].
\nHydrochloric acid, phosphoric acid, sulfuric acid, ferric sulfate acid, para toluene sulfonic acid (PTSA), and Lewis acid (AlCl3 or ZnCl2) are normally used as an acid catalyst. The acid catalyst is preferable over alkaline catalysts for their better results with high FFA oil and the presence of water. However, the time taken for the reaction is much more (3–48 h). It is observed that wet washing of the oil uses a large quantity of water for the removal of unreacted acid or base catalyst and the leftover salt of the neutralization process [32].
\nTransesterification process has relatively high conversion efficiency, small energy usage, and lower cost of catalyst and reactants [10, 31]. The transesterification process has certain challenges including long reaction time, poor catalyst solubility, and poor separation of the products. Besides this, the wastewater produced during the process can cause environmental issues. To overcome these challenges, other faster methods such as supercritical fluid methods have been developed, which complete in a very short time (2–4 min).
\nFurthermore, the absence of catalyst helps in easy recovery of glycerol and purification of biodiesel, which makes the process environment-friendly [10, 25, 33]. However, the method is having a limitation of the higher cost of equipment and working at high temperature and pressures. Methanol requirement is also higher (methanol to oil molar ratio—40:1) [34, 35]. Transesterification reaction is dependent upon several factors. For better yield, reaction time, temperature, agitation speed, molar ratio, and catalyst concentration need to be set in the right manner [14, 31].
\nAs described in the previous section, biodiesel is a preferable choice as an alternative to diesel. Jatropha biodiesel has received a great attention due to high conversion and its relatively competitive cost. Several exhaust and performance characteristics were evaluated by Chauhan et al. [36] on blends of diesel and biodiesel derived from oil of Jatropha in an unmodified diesel engine. The authors reported that for the test blends, performance and emission parameters were better, with some higher NOx emissions and BSFC than that of diesel. Similar studies were conducted by Nalgundwar et al. [37], and Huang et al. [38], which showed the same characteristics of Jatropha biodiesel. According to Bari et al. [39], combustion characteristics of 20% Jatropha biodiesel (B20) blend and D100 were comparable. Due to heavier particles and low volatility of biodiesel, B20 takes more combustion time than D100. The authors concluded that in a conventional diesel engine, B20 (a blend of diesel and Jatropha biodiesel) can be used without any modification. Similarly, Ganapathy et al. [40] conducted experiments on a full-factorial design using diesel and Jatropha biodiesel with 27 runs for each fuel. Some increase in BTE was observed with an advancement in injection timing. This has also caused a reduction in HC, CO, smoke emissions, and BSFC. For Jatropha biodiesel, small increments are observed for HRRmax, Pmax, and NO emission. Injection timing of 340 crank angle degree (CAD) increased HRRmax, Pmax, and BTE. Mofijur et al. [41] evaluated the feasibility of biodiesel derived from Jatropha oil in Malaysia. Interestingly, only 10 and 20% of biodiesel was blended with diesel to consider engine performance and emission as compared to 100% diesel. There is 4.67% reduction in brake power (BP) for B10 and 8.86% for B20. It was seen that there is some increase in BSFC with the increase in the amount of biodiesel in the blends. In comparison to D100, 16 and 25% reduction in CO emission, 3.8 and 10.2% reduction in HC emission and 3 and 6% increase in NOx emission using B10 and B20 blends were observed. The authors concluded that up to 20% biodiesel can be a potential substitute to diesel, which can be used without alteration in the diesel engine.
\nKaranja biodiesel is another substitute in which researcher showed more interest. Dhar and Agarwal [42] investigated several characteristics of blends of diesel and Karanja biodiesel on the engine. The engine is set to run at variable loads and speed. The authors observed that 10 and 20% Karanja biodiesel blends exhibited higher values of maximum torque than diesel. However, for higher biodiesel concentrations in the blends, maximum torque attained was slightly lower. It is also observed that the BSFC of biodiesel blends increases with a percentage increase of biodiesel in the blends, while, for lower concentrations, it is very close to diesel. From emission results, it is seen that HC, CO, and smoke emissions were lower for the blends than diesel with slightly higher NOx emissions. The authors concluded that up to 20% blends of Karanja biodiesel and petroleum diesel are well suited for an unmodified diesel engine. Similar outcomes were found by Raheman and Phadatare [43] and Nabi et al. [44]. The engine emissions including CO and smoke reduced with some reduction in engine noise, but NOx emissions increased in small quantities. Hundred percent KME reduced CO emissions from the diesel engine by 50% and smoke emissions by 43%, while NOx emission increased by 15%. Chauhan et al. [45] conducted transesterification of Karanja oil and observed that all the properties were within the standard limits. The engine trials confirmed that BTE for Karanja biodiesel blended with diesel in a ratio of 5, 10, 20, 30, and 100% was about 3–5% lower with respect to neat diesel. It was also revealed by the engine trials that CO, CO2, UBHC, and smoke emissions were lowered by the use of biodiesel derived from Karanja oil. However, Karanja biodiesel and its blends as compared to diesel produced a little higher quantities of NOx emissions with lower values of HRR and peak cylinder pressure. The results suggested that Karanja biodiesel and its blends will be a viable alternative to diesel, and they shall also be beneficial for small- and medium-energy production.
\nSahoo et al. [46] explored Polanga (
Raheman and Ghadge [48] used biodiesel derived from Mahua (
Hajra et al. [53] produced biodiesel from Sal oil (
Some researcher showed their interest in waste cooking oil biodiesel. In this sequence, Muralidharan et al. [56] tested biodiesel blends (20, 40, 60, and 80%) in a single-cylinder VCR engine at 21 CR and a constant speed of 1500 rpm. The performance parameters included brake power, specific fuel consumption, brake thermal efficiency, exhaust gas temperature, mechanical efficiency, and indicated mean effective pressure. The exhaust gas emission was found to contain nitrogen oxides, hydrocarbon, carbon monoxide, and carbon dioxide. The results confirmed substantial improvement in the performance parameters and exhaust emissions as compared to diesel. The blends helped in reduction of hydrocarbon, carbon monoxide, and carbon dioxide with slightly higher nitrogen oxide emissions. It has been deduced that waste cooking oil biodiesel and diesel blend combustion characteristics are very close to diesel.
\nButanol in the last decade has emerged as a promising biofuel for its application in the diesel engines. Like ethanol, butanol is a biomass-based renewable fuel that may be produced by fermentation [55, 56, 57, 58]. It is a next-generation greener fuel and also known as 1-butanol, n-butanol, or butyl alcohol. Efforts are made by the research community to explore efficient methods for obtaining this alcohol in bio-refineries, wherein higher alcohols are produced from shorter alcohols [59, 60]. Butanol is linear four carbon aliphatic alcohol having a molecular weight of 74.12 g/mol. It has a distinct aroma with a strong alcoholic odor. It is low hydrophobic colorless and flammable liquid.
\nEthanol has received more attention the world over. However, butanol is a better option with high energy content and better physicochemical properties. Butanol was discovered in 1852 by Wirtz, and in 1862, Pasteur concluded that butyl alcohol was a direct product of anaerobic conversion [57].
\nButanol having excellent fuel qualities is very suitable as a diesel engine fuel. Butanol being renewable is not only sustainable but also possesses higher cetane number and heating value than ethanol. It has a higher flash point making it safer, and it has a lower vapor pressure. Butanol is hydrophilic in nature and easy miscible with diesel. This eliminates the problems, which are experienced with lower alcohols such as nonmiscibility [58]. The important properties of n-butanol, ethanol, and diesel are shown in Table 1.
\nProperties | \nDiesel fuel | \nn-Butanol | \nEthanol | \n
---|---|---|---|
Chemical formula | \nC14.09H24.78 | \nC4H9OH | \nC2H5OH | \n
Specific gravity | \n0.85 | \n0.81 | \n0.79 | \n
Boiling point | \n190–280 | \n108.1 | \n78.3 | \n
Net heating value (MJ/kg) | \n42.6 | \n33 | \n27 | \n
Heat of vaporization (KJ/kg) | \n600 | \n578.4 | \n900 | \n
Octane number | \nNA | \n94 | \n92 | \n
Cetane number | \n45 | \n17 | \n8 | \n
Flash point (°C) | \n65–88 | \n35 | \n13 | \n
Viscosity (mm2/s) at 40°C | \n1.9–3.2 | \n2.63 | \n1.2 | \n
Auto-ignition temperature (°C) | \n210 | \n385 | \n434 | \n
Stoichiometric air/fuel ratio | \n14.6 | \n11 | \n9 | \n
Molecular weight | \n193.9 | \n74 | \n46 | \n
Latent heat of evaporation (kJ/kg) | \n265 | \n585 | \n900 | \n
Bulk modulus (bar) | \n16,000 | \n15,000 | \n13,200 | \n
Lubricity (μm) | \n310 | \n590 | \n950 | \n
% of carbon (wt.) | \n86.7 | \n64.9 | \n52.1 | \n
% of hydrogen (wt.) | \n12.7 | \n13.5 | \n13.1 | \n
% of oxygen (wt.) | \n0 | \n21.5 | \n34.7 | \n
C/H ratio | \n6.8 | \n4.8 | \n4 | \n
Production of butanol is carried through the chemical process, that is, fermentation by bacteria. Clostridium acetobutylicum is the most popular species of bacteria used for fermentation. The process is abbreviated as ABE because of the end products—acetone, butanol, and ethanol are obtained from it. Butanol production is carried out by molasses (consists of fermentable sugars—55 wt.% and nonfermentable solids—30 wt.%), water, and nutrients in the reactor. Nutrients and diluted molasses are allowed to combine in the tank. Sterilization of the mixture is continuously carried out. The broth containing ethanol, acetone, and butanol is removed from the reactor. It also contains small quantities of butyric acids, acetic acids, proteins, cells, and molasses (in the form of nonfermentable solids), which are then separated in distillation columns to give the final products [60].
\nSome experimental studies have highlighted the favorable effects of n-butanol/diesel fuel blend in diesel engine [61]. Work of different researchers is highlighted later.
\nAtmanli et al. performed an engine trial on wide operating conditions at varying blend of diesel fuel, cotton oil, and n-butanol using RSM. Homogeneity was observed along with no phase separation. BMEP, brake power, and thermal efficiency of the blend were reduced; however, BSFC has increased marginally. Emissions namely HC, NOx, and CO of the blends have reduced [62]. Yilmaz et al. studied the emissions and performance characteristic of butanol/biodiesel blends in a multi-cylinder, indirect injection diesel engine. Butanol blended with biodiesel was compared with standard diesel (D100) and neat biodiesel (B100) at four engine loads. Lower exhaust gas temperatures and nitrogen oxide (NOx) emissions with higher CO and HC emissions were found [63]. Zhu et al. [64] carried experiments on n-butanol blends, EGR rate, and injection timing on a modified diesel engine. The results suggested that with increased EGR rate, NOx emissions reduce, but smoke emissions increase. With the increase of n-butanol fraction, smoke emissions were found to decrease with a small increase in NOx.
\nDogan conducted some studies on a diesel engine at four different loads. No phase separation was observed in 20% butanol/diesel blend. The performance was slightly improved in comparison to diesel. Gaseous emissions, for example, NOx, CO, smoke content, and exhaust gas temperature reduced with the blends [65]. Butanol/diesel blends (8, 16, and 24%) were prepared by Rakopoulos et al., and it was found during the trial that the smoke opacity, NOx, and CO emissions were significantly reduced. However, the HC emissions were higher. Greater SFC and BTE and slightly lesser exhaust gas temperatures were noted in comparison to petroleum diesel [66]. In a similar study, Karabektas et al. evaluated the suitability of butanol-diesel blends in a diesel engine. Four blends were prepared consisting of 5, 10, 15, and 20% butanol by volume. Brake power was lower, whereas BSFC rose with the addition of butanol. CO and NOx levels were lower for blends; however, there was a considerable increase in HC emissions [67]. In another study, Lebedevas et al. conducted investigations on a multi-cylinder diesel engine.
\nTwo types of test fuels were prepared. The first is comprised of diesel, rapeseed methyl ester (RME), and butanol, and the second consisted of diesel, rapeseed oil butyl esters (RBE), and butanol. Almost the same efficiency was observed, and there was a significant reduction in CO and HC emissions. NOx emissions remained almost the same; however, there was a reduction in smoke emissions for all butanol-based fuels as compared to petroleum diesel [68]. The above studies suggest that butanol-diesel blends are potential alternative fuel in a diesel engine.
\nBiomass-based producer gas is a viable alternative to conventional fuels, where there is a large availability of the biomass as a primary source. Biomass feasible for producer gas is dry materials such as wood, charcoal, rice husks, and coconut shell. Producer gas is produced by gasifying these dry carbonaceous organic materials. In the gasification process, the solid biomass is broken down by the use of heat. The gasification system consists of a reactor or container into which the biomass is fed along with a gasification agent such as air, oxygen, and steam. According to the supply, producer gas with different calorific values is produced. When air is used, the gas with 4–6 MJ/Nm3 calorific value is produced, and the gas can be used for direct combustion or as an internal combustion engine fuel. With oxygen, the gas produced has 10–15 MJ/Nm3 calorific value. The producer gas with 13–20 MJ/Nm3 calorific value is produced with steam as a gasifying agent, and the gas can be subsequently used as a feedstock for methane and methanol production [69, 70].
\nProducer gas was produced from sugarcane bagasse and carpentry waste by Singh and Mohapatra [71]. The authors mixed the raw materials thoroughly in the ratio 1:1, and the major steps followed for gasification are mentioned here. (1) In the first step, the mixed raw material is fed from the top into a downdraft gasifier, and air enters over air inlets through which firing also takes place using a diesel torch. After operation of the gasifier for 15–20 min, the gas constantly comes out of the gasifier at a temperature of nearly 450°C. (2) In the second step, the gas is cooled and cleaned in the scrubber. As the gas is passed through a jet of cold water, the particulates, dust, and gases such as HCl, H2S, SO2, and NH3 are removed as they are water soluble. All the tar present in the gas is also washed in the scrubber. (3) In the third step, the gas is passed through a drum-shaped secondary filter containing a mixture of wood chips and powder. As the gas passes through the filter, the particulate matter is absorbed along with the excessive moisture present. Gas with high purity and temperature of nearly 50°C comes out of the filter. (4) In the final step, the gas is passed through a safety filter, which contains a paper filter. The minute soot particles are absorbed by the filter and gas with higher purity, and 35°C temperature is obtained.
\nIn spark ignition engines, the use of producer gas is already established. However, its use in a dual fuel CI engine as an inducted fuel is still a topic of research [72]. In dual fuel engines, the producer gas is inducted along with the air into the cylinder, and it is ignited by injecting a small quantity of diesel or other similar fuel such as biodiesel. Some of the research on producer gas being used as a dual fuel compression ignition engine fuel is discussed here. Ramadhas et al. [73] used producer gas produced from coir pith and wood for fueling a dual fuel engine with diesel as the direct injected fuel. The authors observed a reduction in brake thermal efficiency with dual fuel operation as compared to neat diesel operation. The energy consumption of dual fuel operation was also higher. At part-load conditions, carbon monoxide and carbon dioxide emissions were higher with dual fuel operations. The smoke density was similar for all the tested fuels. The authors found that producer gas (made from wood chips) fueled dual fuel operation performed well than coir pith engine operation. Also, the engine could be run only to 50–60% of the maximum load. In another study by Ramadhas et al. [74], coir pith was used to produce producer gas, and rubber seed oil was used as the direct injected fuel. The authors observed that with diesel and rubber seed oil, the engine performance reduced in dual fuel mode. The fuel consumption with rubber seed oil as direct injected fuel is more than diesel as a pilot fuel. At all loads, the carbon monoxide and carbon dioxide emissions are higher with rubber seed oil-fueled dual fuel operation on account of higher fuel consumption due to lower calorific value of fuel. The other exhaust emissions are almost the same. Similar study was conducted by Singh and Mohapatra [71], who directly injected diesel and inducted producer gas in the air produced from sugarcane bagasse and carpentry waste mixed equally during gasification. The authors observed a maximum reduction of 45.7% in consumption of diesel and 69.5% reduction in NOx emissions along with a slight increase in engine noise.
\nSingh et al. [75] blended refined rice bran oil (75% v/v) with diesel and used producer gas produced from wood in a three-cylinder diesel engine. It was observed that at 84% of the maximum engine load with a compression ratio of 18.4:1, the pollutant concentration reduced by 48.28, 61.06, and 80.49% for HC, NO, and NO2, respectively; however, in comparison to diesel, CO emission increased by 16.31%.The authors also observed an increase in noise levels with producer gas induction at all the loads. Honge oil and Honge oil methyl ester were used as a pilot fuel with producer gas as the injected fuel with and without carburetor by Banapurmath and Tiwari [76]. The authors found that producer gas and honge oil engine operation resulted in higher emission levels and low thermal efficiency due to lower heat content and high viscosity of honge oil along with the low burning speed of producer gas. With methyl ester of honge oil and producer gas in dual-fuel engine operation, brake thermal efficiency improves on account of higher calorific value and low viscosity. Overall, with dual fuel operation, smoke and NOx emissions reduce, whereas HC and CO emissions increase considerably.
\nCarlucci et al. [77] used biodiesel and a synthetic producer gas for a dual fuel engine operation. The authors initially varied the injection pressure, injection timing of biodiesel with a single-pilot injection, and also varied the producer gas flow rate. The results revealed that the combustion is affected by both injection timing and pressure. The thermal efficiency was higher with slightly advanced injection timing along with low injection pressure. Lowering of unburned hydrocarbons and carbon monoxide emissions was observed, whereas an increase in NOx emission occurs. In the second phase, the splitting of the pilot fuel injection was carried out, which leads to improved fuel efficiency and reduced pollutants compared to single-pilot fuel injection at low loads. The authors also concluded that injection pressure plays a vital role in reducing gaseous emissions.
\nHydrogen is a colorless, odorless gas, which produces heat and water when combusted with oxygen at high pressure and temperature. Hydrogen has high energy content as compared to other fuels. However, its density is low, that is, the storage space required for a vehicle to run on hydrogen for the same distance is more than gasoline [78]. Table 2 compares the properties of hydrogen with diesel and gasoline.
\nProperty | \nGasoline | \nDiesel | \nHydrogen | \n
---|---|---|---|
Density at 1 atm. and 15°C (kg/m3) | \n721–785 | \n833–881 | \n0.0898 | \n
Stoichiometric A/F | \n14.8 | \n14.5 | \n34.3 | \n
Flammability limits (Vol.% in air) | \n1.4–7.6 | \n0.6–7.5 | \n4–75 | \n
Auto-ignition temperature (°C) | \n246–280 | \n210 | \n585 | \n
Lower calorific value at 1 atm. and 15°C (kJ/kg) | \n44,500 | \n42,500 | \n120,000 | \n
Properties of gasoline, diesel, and hydrogen.
The flammability limits of hydrogen are wide, which make its use suitable for a wide range of air-fuel mixture. The engine can be operated at lean mixtures, which considerably improves the fuel economy as complete combustion takes place with few residues. Hydrogen has high diffusivity and flame speed because of which faster combustion takes place at near constant volume. However, due to its high auto-ignition temperature, it is suitable for a spark ignition engine, whereas for its use in a diesel engine, a low auto-ignition temperature fuel is required to initiate combustion. Also, the engine may knock or detonate due to its low ignition energy requirement.
\nHydrogen in gaseous state is not available on Earth due to its low density as it is pushed out from the gravitational pull of the Earth. However, it exists in the combined form in natural resources such as coal, natural gas, fossil fuels, and water. Presently, small amount of hydrogen is produced using renewable sources such as wind, solar, geothermal energy, and biomass, and nearly 95% of hydrogen is produced from fossil fuels. Therefore, the hydrogen production is costly, and a large amount of emissions are produced. For a true hydrogen economy to exist, the hydrogen needs to be produced abundantly and economically from renewable sources. Hydrogen can be produced by natural gas reforming, gasification of biomass, and electrolysis of water.
\nMethane reforming is the most common method of hydrogen production in the United States. In this method, methane and steam are reformed at 3−25 bar pressure and 700–1000°C temperature in the presence of a catalyst. The by-products of the reaction are carbon monoxide and carbon dioxide. Heat is required for the process as it is endothermic. The carbon monoxide subsequently is reacted with steam in the presence of a catalyst, resulting in the formation of carbon dioxide and hydrogen. This reaction is called water gas shift reaction. Lastly, using the pressure-swing adsorption process, the gas is freed of all the carbon dioxide and other impurities, which leaves only pure hydrogen [79]. The steam reforming can also be carried out on other fuels such as ethanol, propane, and even gasoline. This process can become truly renewable if hydrogen is produced from renewable sources.
\nHydrogen can be produced by gasification of biomass and coal. Biomass is a renewable source, which includes crop residue, forest residue, algae, crops grown specifically for energy use (switchgrass), municipal wastes, and animal waste. Since carbon dioxide is captured from the atmosphere by biomass itself, the net carbon emissions of the process are low. In gasification process, the carbon-rich material at a temperature greater than 700°C is converted to hydrogen, carbon monoxide, and carbon dioxide in the presence of oxygen and/or steam. Water is then reacted with carbon monoxide to form carbon dioxide and more amount of hydrogen via the water-gas shift mechanism. Gasification process can also be carried out using solar energy [80].
\nHydrogen and oxygen can form by passing an electric current through water. The process is called electrolysis, and this process consumes the highest energy for production of hydrogen [81]. However, the process is clean and free of emission if the energy source used for electricity production is renewable.
\nHydrogen can also be produced from other sources such as reforming of renewable liquid, splitting of water using solar, high-temperature thermochemical water splitting, and microbes [82, 83].
\nHydrogen is a carbon-free substance; therefore, no greenhouse gas emissions take place from its combustion in an IC engine. Hydrogen has good heat transfer characteristics, which increases the combustion temperature resulting in improved engine efficiency even at lean mixture operation [84]. This section describes the methods and the compression ignition engine performance characteristics when operated in dual fuel mode with hydrogen.
\nBack in 1978, Homan et al. [85] used hydrogen to operate a diesel engine. The authors realized that the engine has limited operation range because of its high auto-ignition temperature, which could not be resolved by even increasing the compression ratio up to 29. They later investigated the use of glow plugs and a multiple strike spark plug. The results showed that both the methods resulted in providing reliable ignition and smooth engine operation. The authors also observed reduction in ignition delay; however, the indicated mean effective pressure was higher than diesel-fueled engine operation. Moreover, the cyclic variations in ignition delay were significant along with the formation of high amplitude waves in the combustion chamber [86].
\nAn indirect injection single-cylinder diesel engine was operated with hydrogen only by Ikegami et al. [87, 88]. The authors found that the engine had limited operation range with hydrogen. The authors were able to extend the operating limit and attain smoother combustion by injecting small amounts of pilot fuel in the swirl chamber as the pilot fuel became the source of ignition for the hydrogen. However, excessive pilot fuel presence resulted in its auto-ignition resulting in rough engine operation.
\nDirect use of hydrogen as CI engine fuel is possible within a limited operating range due to its high auto-ignition temperature. To increase the engine’s operation range, hydrogen needs to be supplemented by a low auto-ignition temperature fuel such as diesel, vegetable oils, and biodiesel. Such an engine is called dual fuel engine, wherein hydrogen is either inducted in a carburetor or injected in the intake manifold or the intake port. The low auto-ignition fuel, called pilot fuel, is injected directly into the combustion chamber when the piston is approaching top dead center and the fuel ignites the hydrogen-air mixture. It has been observed that port injection of hydrogen shows better engine performance and reduction of emissions in comparison to manifold injection or use of a carburetor [89, 90, 91].
\nVarde and Frame [92] aspirated small amounts of hydrogen in the intake of a single-cylinder diesel engine for investigating the possibility of smoke reduction. They observed that the smoke levels reduced at part- and full-load conditions. The optimum hydrogen energy share for smoke reduction lies between 10 and 15%. At optimum energy share, the smoke reduced by nearly 50 and 17% at part- and full-load conditions, respectively. Unburned hydrocarbon emission was not affected by hydrogen injection; however, NOx emission increased with an increase in hydrogen addition especially at loads above 50% of full load. The NOx emission increase is due to the increase in the combustion temperature, which increases with an increase in hydrogen addition as well as load. Lilik et al. [93] also observed an increase in NOx emission for a hydrogen dual fuel engine with diesel as a pilot fuel. The authors injected hydrogen in the intake air up to 15% of the energy share. The authors also observed a shift in the ratio of nitrogen oxide to nitrogen dioxide, wherein the nitrogen oxide decreased and nitrogen dioxide increased.
\nExhaust gas recirculation (EGR) has been proved to be the best method for NOx reduction and for suppressing knocking in a hydrogen dual fuel engine [94, 95, 96]. In EGR, the exhaust gas is reintroduced in the cylinder. As it has high-specific heat, it absorbs the combustion heat and reduces the cylinder temperature leading to reduction in NOx formation. However, introducing the exhaust gas also reduces the amount of oxygen available resulting in increase in smoke, CO, and HC emission. Although these emissions may increase, they will be still lower than diesel operation [97].
\nBose and Maji [95] compared the performance and emission characteristics with and without EGR of a neat diesel engine and a hydrogen diesel dual-fuel engine. The brake thermal efficiency without EGR for hydrogen fueled engine was higher than neat diesel operation. Higher flow rates of hydrogen deteriorated the engine efficiency. The engine efficiency was adversely affected by EGR. The smoke emissions reduced with hydrogen induction; however, with EGR, the smoke levels increased, but they were still lower than neat diesel operation. The authors observed that in order to reduce NOx emissions by 40%, 20% EGR is necessary.
\nSaravanan and Nagarajan [98] injected hydrogen in a dual-fuel diesel engine using a carburetor, injector placed in the port (TPI) and injector placed in the manifold (TMI). The port injector and manifold injector were located 5 and 100 mm from the intake valve seat, respectively. The injection timing used for diesel was 23°BTDC. The optimized injection timing for hydrogen port injection was 5° before gas exchange top dead center (BGTDC) with 30° CA injection duration. The observations made during running of the engine at different operating conditions were as follows: (a) engine operation was unstable during the late injection (30°AGTDC) especially at higher loads and with the injection duration of 90°CA, (b) knocking of the engine at flow rates greater than 25 lpm, and (c) with port and manifold injection of hydrogen greater than 20 lpm flow rate, smoke emissions increased rapidly. The brake thermal efficiency and peak heat release rate were high for both port and manifold injections. The engine efficiency with carburetion was lower than neat diesel operation. NOx was higher for both TPI and TMI modes. HC, CO, CO2, and smoke emissions reduced with all the three modes. It was concluded that using H2 as a fuel and adopting TPI gave better efficiency and emission reduction than all the other modes.
\nThe challenge with hydrogen induction is that at high loads, the engine performance is limited due to knocking. EGR is one of the ways to extend the knock limit of the engine, but as discussed earlier, it tends to increase the harmful emissions. Another way of reducing the knock at higher loads is injection of water as it can control the combustion phase. Chintala and Subramanian [99] inducted water at various specific water consumption (SWC) in a hydrogen-fueled dual fuel engine. The authors found that the optimum SWC of 200 h/kWh lead to a knock-free operation up to 20% hydrogen energy share resulting in 24% NOx emission reduction and 5.7% reduction in efficiency. The carbon monoxide emission increased from 0 g/kWh without water injection to 1.2 g/kWh with water injection. The authors conducted another study [100], wherein they were able to increase the hydrogen energy share without knocking of the engine from 18 to 24 and 36% by retarding the injection timing and injecting water, respectively.
\nNatural gas can also be used as an injected fuel in a dual fuel engine. However, the engine efficiency is low followed by high emissions due to slow rate of burning of natural gas. Hydrogen can be used to supplement natural gas such that the engine’s performance can improve and the emissions can reduce. One such study was conducted by McTaggart-Cowan et al. [101], wherein the authors used a single-cylinder engine fueled with natural gas blended with 10 and 23% hydrogen (by volume). In this study, the mixture of hydrogen and methane was injected directly into the cylinder, and diesel was used as a pilot fuel. Diesel was injected approximately 1 ms prior to the natural gas to initiate the combustion process. The dual fuel injector used concentric needles. The results show that with 10% H2, NOx, and PM emissions remained almost the same though CO and THC were slightly reduced. With 23% H2, NOx increased slightly, while CO, THC, and CO2 were reduced. Also, the peak heat release rate was 20% higher than natural gas. With PM, significant influence was seen at latest injection timings (15° ATDC), where it was found to decrease. At such timings, the burn duration for 23% H2 was also substantially reduced. The combustion variability (COVGIMEP) for 10% H2/methane fuel reduced only at late timings, while with 23% H2, it reduced for all injection timings. The combustion stability was found to improve, and the effect of hydrogen addition was observed to be consistent with variations in injection timings and pressure.
\nBiodiesel and its blends with diesel have also been used by many researchers as a pilot fuel in a hydrogen-fueled dual fuel engine. Geo et al. [102] used rubber seed oil and rubber seed oil methyl ester as the direct injected fuel and hydrogen as the injected fuel in the intake port in a dual fuel engine to reduce smoke and increase the engine’s thermal efficiency. The brake thermal efficiency of the engine increased by nearly 1.5%, whereas the smoke emission reduced by more than 30% with hydrogen induction. The maximum hydrogen energy share at full load that the engine can tolerate was 12.69% with diesel, 11.2% with rubber seed oil methyl ester, and 10.76% with rubber seed oil. The HC and CO emissions reduced at all loads with hydrogen induction for all the fuels. However, the NOx emissions increased for all the fuels with an increase in hydrogen induction. The authors attributed the increase to high combustion temperature because of high premixed combustion. The authors also observed higher emission values and lower efficiency with rubber seed oil due to poor mixture formation because of high viscosity of the fuel.
\nPalm oil methyl ester was blended with diesel in various proportion, and the blends were used as a pilot fuel in a single-cylinder dual fuel engine along with hydrogen as the injected fuel [103]. The performance and emission characteristics of the engine were recorded at 50% load and full load. The authors observed that at 25% blend of palm oil methyl ester in a liter of diesel, the engine gave the best efficiency at 5 lpm flow rate of hydrogen. Hydrogen induction resulted in drastic reduction in carbon monoxide emissions. However, unburnt hydrocarbon emissions increased at 5 lpm flow rate, but with increase in flow rate to 10 lpm, some reduction in emission level was observed.
\nBiodiesel produced from waste cooking oil can also be used as a pilot fuel in a hydrogen dual fuel engine. Kumar and Jaikumar [104] used waste cooking oil (WCO) and emulsion of waste cooking as direct injected fuel and hydrogen as manifold injected fuel in a dual fuel engine. Dual fuel operation reduced CO, HC, and smoke emissions with waste cooking oil as a pilot fuel at all loads; however, thermal efficiency reduced at 40% load. The ignition delay with WCO emulsion is higher than neat WCO, which further increases with hydrogen induction. The authors observed improvement in engine performance with hydrogen induction at high loads and fall in performance at low loads with WCO emulsion as a pilot fuel.
\nDimethyl ether (DME) is the simplest ether with chemical formula of CH3OCH3. DME in gaseous state is colorless, nontoxic, and highly flammable with a slight narcotic effect. By slightly pressurizing the gas, it can also be handled as a liquid fuel. DME and liquefied petroleum gas have similar properties. Moreover, the cetane number of DME is greater than 55. A blue flame is visible while burning DME, and it has wide flammability limits [105, 106, 107, 108]. Table 3 shows the physicochemical properties of DME and diesel.
\nProperty | \nDME | \nDiesel | \n
---|---|---|
Vapor pressure at 20°C (bar) | \n5.1 | \n<0.01 | \n
Boiling temperature (°C) | \n−25 | \n~150–380 | \n
Liquid density at 20°C (kg/m3) | \n660 | \n800–840 | \n
Liquid viscosity at 25°C (kg/ms) | \n0.12–0.15 | \n2–4 | \n
Gas specific gravity (vs air) | \n1.59 | \n– | \n
Lower heating value (MJ/kg) | \n28.43 | \n42.5 | \n
Cetane number | \n55–60 | \n40–55 | \n
Stoichiometric A/F ratio (kg/kg) | \n9.0 | \n14.6 | \n
Enthalpy of vaporization at normal temperature and pressure (kJ/kg) | \n460 (−20°C) | \n250 | \n
Properties of DME and diesel [109].
Advantages of dimethyl ether are as follows: (a) high content of oxygen and the absence of any bond between carbon atoms result in low smoke formation, (b) low boiling point results in quick evaporation of fuel spray, and (c) auto-ignition temperature of DME is low, and its cetane number is high, which reduces the physical ignition delay [110]. The disadvantages of DME are as follows: (a) the calorific value is less due to the presence of oxygen molecules, hence the fuel required to produce the same power is more; (b) it has viscosity lower than diesel, which causes leakage in the fuel system, and due to its low lubricity, the fuel injection system surface wear may be high; and (c) its bulk modulus of elasticity is low, it can be compressed nearly four to six times that of diesel, and more work has to be put in the fuel pump to compress the fuel to the same level of diesel [111].
\nDME is usually used as a spray-can propellant and in cosmetics. Both fossil fuels and renewable energy sources can be used to produce DME. Dehydrogenation of methanol and direct conversion of syngas [112] are the two processes used for DME production. The two methods are essentially similar.
\nIn the direct conversion method, syngas can be used to simultaneously produce DME and methanol using suitable catalysts. The first step of the direct conversion process is the conversion to syngas by either reforming natural gas using steam or partial oxidation of coal and biomass by using pure oxygen. In the second step, a copper-based catalyst is used to synthesize methanol from syngas. In the third step, alumina or zeolite-based catalyst is used to dehydrogenate methanol to form DME. Lastly, the raw product is purified as it may contain some amount of methanol and water. Bio-DME can be produced using renewable sources; however, the production route is costly relative to diesel [110].
\nDME can be used in an engine as a neat fuel or by blending it with diesel, biodiesel, or LPG. This section briefly describes the effect of DME on a diesel engine in terms of its efficiency, combustion, and the exhaust emissions.
\nA direct injection single-cylinder diesel engine was used by Sato et al. [113] for operating with DME. The engine was supercharged with a multiple hole injector. The authors observed that heat release and combustion pressure with DME-fueled engine are higher than diesel. Also, the engine had lower ignition delay and higher indicated mean effective pressure with DME engine operation than diesel engine operation. The authors found NOx emission reduction by one-third with DME with an increase in the exhaust gas recirculation rate. Carbon dioxide emission was lower than diesel. In middle- and low-load conditions, the energy consumption was higher than diesel.
\nThe fuel injection system of a diesel engine needs to be redesigned for operating with DME due to its low lubricity, viscosity, lower heating value, and elasticity. Lubricity can be improved by adding additives; however, for other issues, new materials need to be developed. DME is soluble in hydrocarbons, which make it a lucrative proposition, such as propane blending improves the calorific value of the blend or biodiesel blending improves the lubricity and viscosity of the blend.
\nYing et al. [114] blended DME with diesel in various proportions and found decrease in lower heating value, kinematic viscosity, and aromatic fraction of the blends. Cetane number, carbon to hydrogen ratio, and oxygen content of the blends increased. The authors found low fuel consumption for the blends at high engine speed than diesel operation. At high engine speeds, the velocity of the plunger is high in the fuel pump, which makes the pressure in the plunger lower than DME vapor pressure, hence vaporizing the DME in the plunger, thereby reducing the effective stroke of the plunger and fuel delivered per stroke. However, at lower speed, the vaporizing rate is not much, hence more quantity of blended fuel is delivered due to high delivery pressure and the fuel consumption is higher. The impact on emissions due to blends varies with varying load conditions. At high loads, the effect of blends on smoke is significant, whereas at low loads, the smoke emission is slightly affected. NOx emission decreases a little, whereas HC and CO emissions increase at all operating conditions. The decrease in NOx emission is due to lower combustion temperature caused by shorter ignition delay and less amount of fuel prepared for premixed combustion caused by high cetane number and lower auto-ignition temperature [113, 115]. Also, the blend injection timing is delayed due to low elasticity [116] than diesel, which further reduces the NOx emission.
\nRapeseed oil was blended with DME at 2, 4, 6, and 10% volume by volume ratio by Wang and Zhou [117]. The results show that engine performance is good with different blends in all operating conditions. With the increase in rapeseed oil percentage in the blend, the power and torque output of the engine increase as well as the NOx emission increases. Smoke emissions were insignificant up to 6% of rapeseed oil in the blend; however, with further increase in rapeseed percentage, the emission level increased drastically. The authors also observed increase in the heat release rate and the fraction of the fuel burned in premixed combustion phase with an increase in rapeseed oil mass fraction.
\nIn another study, Hou et al. [118] used blends of used cooking oil and DME in a turbocharged compression ignition engine. The authors also observed that increase of DME proportion in the blends reduced the peak in-cylinder temperature, pressure, ignition delay, and peak heat release rate. The authors varied the nozzle hole diameter (0.35 and 0.4 mm) and found that peak cylinder pressure and heat release are higher for 0.35 mm nozzle, and the combustion phase is also advanced. NOx emissions with 0.4 mm diameter are lower than 0.35 mm diameter at 100% DME, whereas at 50% blend of DME, NOx emission is higher with 0.4 mm diameter than 0.35 mm diameter. HC and CO emissions are lower with 0.4 mm diameter at 50% blend of DME, and the emissions increased when 100% DME is used with 0.4 mm diameter nozzle.
\nSince DME and LPG have similar physicochemical properties, DME can be handled and stored in a similar manner. Also, the infrastructure used to supply LPG can be used for DME supply for DME-fueled vehicles [119, 120]. DME and LPG can be easily blended, and they compensate for each other’s disadvantage namely LPG’s low cetane number and DME’s low calorific value.
\nLee et al. [121] used a single-cylinder diesel engine for operating with blends of n-butane and DME. The n-butane was varied from 0 to 40% by mass in the blend. The n-butane content above 30% resulted in poor self-ignition and unstable combustion, especially at low loads. The increase in n-butane content led to late start of combustion due to ignition delay caused by reduced cetane number. High HC and CO emissions were observed with higher n-butane content due to partial burning of the charge caused by over mixing of the unburnt charge and the burnt charge. NOx emissions were higher at low loads and low n-butane content, which are mainly due to early start of combustion giving more time for NOx formation. Whereas, at high load and high n-butane content, the NOx emission is higher. Also, the NOx emissions are lower with blended fuels than diesel engine operation. Less smoke emissions were detected for medium and low loads.
\nAs already highlighted, depleting petroleum reserves and climate change is mandating the use of alternative fuel to give a new life to millions of off- and on-road engines. The benefits of alternative fuels are enormous for developing countries such as energy security, social empowerment, employment generation, and substantial savings of foreign exchange. The fossil fuels are neither sustainable nor inexhaustible, and alternatives must be explored to address different issues with the use of petroleum-derived fuels.
\nThere are greater challenges with the use of alternative fuels due to their adaptability with the vital parts of engines, cost, availability of feedstocks, and so on. Also, knowledge of important chemical, physical, thermodynamic, and logistics features of the alternative fuel are very much required for large-scale adaptation. Moreover, production of alternative fuels is a complex process, and keeping track of constantly upgrading technology shall be very helpful to drastically reduce the cost and production time.
\nIt is not possible for a single-alternative fuel to completely replace the diesel, and various options have both positive and negative attributes. The alternative fuels reduce the risk to health as they are clean burning. The engine performance is quite similar, and well-to-wheel analysis is required for estimating the operating cost. Since various disciplines are linked with production and adaptation of alternative fuels, synergy is necessary among research fraternity to understand the efficacy of different options. Some of the fuels are very promising, but further research is required to prove their potential. It is envisaged that with the enforcement of more stringent norms, the alternative fuels would become more attractive either as a drop in fuels or blend. It can be concluded that diesel engines can be fueled in an efficient and sustainable way with various options of alternative fuels with some trade-off on price and performance; however, they are capable of bringing a new era of green environment.
\nAt IntechOpen, we not only specialize in the publication of Book Chapters as part of our Edited Volumes, but also the publication and dissemination of longer manuscripts, known as Long Form Monographs. Monographs allow Authors to focus on presenting a single subject or a specific aspect of that subject and publish their research in detail.
\n\nEven if you have an area of research that does not at first sight fit within a previously defined IntechOpen project, we can still offer support and help you in publishing your individual research. Publishing your IntechOpen book in the form of a Long Form Monograph is a viable alternative.
",metaTitle:"Publish a Whole Book",metaDescription:"At IntechOpen, we not only specialize in the publication of book chapters as part of our Edited Volumes, but also the publication and dissemination of long form manuscripts, known as monographs. Monographs allow authors to focus on presenting a single subject or a specific aspect of that subject and publish their research at length.\n\nPerhaps you have an area of research that does not fit within a previously defined IntechOpen project, but rather need help in publishing your individual research? Publishing your IntechOpen book in the form of a long form monograph is a great alternative.",metaKeywords:null,canonicalURL:"/page/publish-a-whole-book",contentRaw:'[{"type":"htmlEditorComponent","content":"MONOGRAPH - LONG FORM MANUSCRIPT
\\n\\nFORMATS
\\n\\nCOST
\\n\\n10,000 GBP Monograph - Long Form
\\n\\nThe final price includes project management, editorial and peer-review services, technical editing, language copyediting, cover design, book layout, book promotion and ISBN assignment.
\\n\\n*The price does not include Value-Added Tax (VAT). Residents of European Union countries need to add VAT based on the specific rate applied in their country of residence. Institutions and companies registered as VAT taxable entities in their own EU member state will not pay VAT by providing us with their VAT registration number. This is made possible by the EU reverse charge method.
\\n\\nOptional Services
\\n\\nIntechOpen has collaborated with Enago, through its sister brand, Ulatus, which is one of the world’s leading providers of book translation services. The services are designed to convey the essence of your work to readers from across the globe in a language they understand. Enago’s expert translators incorporate cultural nuances in translations to make the content relevant for local audiences while retaining the original meaning and style. Enago translators are equipped to handle all complex and multiple overlapping themes encompassed in a single book and their high degree of linguistic and subject expertise enables them to deliver a superior quality output.
\\n\\nIntechOpen Authors that wish to use this service will receive a 20% discount on all translation services. To find out more information or obtain a quote, please visit: https://www.enago.com/intech.
\\n\\nFUNDING
\\n\\nWe feel that financial barriers should never prevent researchers from publishing their work. Please consult our Open Access Funding page to explore funding opportunities and learn more about how you can finance your IntechOpen publication.
\\n\\nBENEFITS
\\n\\nPUBLISHING PROCESS STEPS
\\n\\nFor a complete overview of all publishing process steps and descriptions, go to How Open Access Publishing Works.
\\n\\nSEND YOUR PROPOSAL
\\n\\nIf you are interested in publishing your book with IntechOpen, please submit your book proposal by completing the Publishing Proposal Form.
\\n\\nNot sure if this is the right option for you? Please refer back to the main Publish with IntechOpen page or feel free to contact us directly at book.department@intechopen.com.
\\n"}]'},components:[{type:"htmlEditorComponent",content:'MONOGRAPH - LONG FORM MANUSCRIPT
\n\nFORMATS
\n\nCOST
\n\n10,000 GBP Monograph - Long Form
\n\nThe final price includes project management, editorial and peer-review services, technical editing, language copyediting, cover design, book layout, book promotion and ISBN assignment.
\n\n*The price does not include Value-Added Tax (VAT). Residents of European Union countries need to add VAT based on the specific rate applied in their country of residence. Institutions and companies registered as VAT taxable entities in their own EU member state will not pay VAT by providing us with their VAT registration number. This is made possible by the EU reverse charge method.
\n\nOptional Services
\n\nIntechOpen has collaborated with Enago, through its sister brand, Ulatus, which is one of the world’s leading providers of book translation services. The services are designed to convey the essence of your work to readers from across the globe in a language they understand. Enago’s expert translators incorporate cultural nuances in translations to make the content relevant for local audiences while retaining the original meaning and style. Enago translators are equipped to handle all complex and multiple overlapping themes encompassed in a single book and their high degree of linguistic and subject expertise enables them to deliver a superior quality output.
\n\nIntechOpen Authors that wish to use this service will receive a 20% discount on all translation services. To find out more information or obtain a quote, please visit: https://www.enago.com/intech.
\n\nFUNDING
\n\nWe feel that financial barriers should never prevent researchers from publishing their work. Please consult our Open Access Funding page to explore funding opportunities and learn more about how you can finance your IntechOpen publication.
\n\nBENEFITS
\n\nPUBLISHING PROCESS STEPS
\n\nFor a complete overview of all publishing process steps and descriptions, go to How Open Access Publishing Works.
\n\nSEND YOUR PROPOSAL
\n\nIf you are interested in publishing your book with IntechOpen, please submit your book proposal by completing the Publishing Proposal Form.
\n\nNot sure if this is the right option for you? Please refer back to the main Publish with IntechOpen page or feel free to contact us directly at book.department@intechopen.com.
\n'}]},successStories:{items:[]},authorsAndEditors:{filterParams:{sort:"featured,name"},profiles:[{id:"6700",title:"Dr.",name:"Abbass A.",middleName:null,surname:"Hashim",slug:"abbass-a.-hashim",fullName:"Abbass A. Hashim",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/6700/images/1864_n.jpg",biography:"Currently I am carrying out research in several areas of interest, mainly covering work on chemical and bio-sensors, semiconductor thin film device fabrication and characterisation.\nAt the moment I have very strong interest in radiation environmental pollution and bacteriology treatment. The teams of researchers are working very hard to bring novel results in this field. I am also a member of the team in charge for the supervision of Ph.D. students in the fields of development of silicon based planar waveguide sensor devices, study of inelastic electron tunnelling in planar tunnelling nanostructures for sensing applications and development of organotellurium(IV) compounds for semiconductor applications. I am a specialist in data analysis techniques and nanosurface structure. I have served as the editor for many books, been a member of the editorial board in science journals, have published many papers and hold many patents.",institutionString:null,institution:{name:"Sheffield Hallam University",country:{name:"United Kingdom"}}},{id:"54525",title:"Prof.",name:"Abdul Latif",middleName:null,surname:"Ahmad",slug:"abdul-latif-ahmad",fullName:"Abdul Latif Ahmad",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:null},{id:"20567",title:"Prof.",name:"Ado",middleName:null,surname:"Jorio",slug:"ado-jorio",fullName:"Ado Jorio",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:{name:"Universidade Federal de Minas Gerais",country:{name:"Brazil"}}},{id:"47940",title:"Dr.",name:"Alberto",middleName:null,surname:"Mantovani",slug:"alberto-mantovani",fullName:"Alberto Mantovani",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:null},{id:"12392",title:"Mr.",name:"Alex",middleName:null,surname:"Lazinica",slug:"alex-lazinica",fullName:"Alex Lazinica",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/12392/images/7282_n.png",biography:"Alex Lazinica is the founder and CEO of IntechOpen. After obtaining a Master's degree in Mechanical Engineering, he continued his PhD studies in Robotics at the Vienna University of Technology. Here he worked as a robotic researcher with the university's Intelligent Manufacturing Systems Group as well as a guest researcher at various European universities, including the Swiss Federal Institute of Technology Lausanne (EPFL). During this time he published more than 20 scientific papers, gave presentations, served as a reviewer for major robotic journals and conferences and most importantly he co-founded and built the International Journal of Advanced Robotic Systems- world's first Open Access journal in the field of robotics. Starting this journal was a pivotal point in his career, since it was a pathway to founding IntechOpen - Open Access publisher focused on addressing academic researchers needs. Alex is a personification of IntechOpen key values being trusted, open and entrepreneurial. Today his focus is on defining the growth and development strategy for the company.",institutionString:null,institution:{name:"TU Wien",country:{name:"Austria"}}},{id:"19816",title:"Prof.",name:"Alexander",middleName:null,surname:"Kokorin",slug:"alexander-kokorin",fullName:"Alexander Kokorin",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/19816/images/1607_n.jpg",biography:"Alexander I. Kokorin: born: 1947, Moscow; DSc., PhD; Principal Research Fellow (Research Professor) of Department of Kinetics and Catalysis, N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow.\r\nArea of research interests: physical chemistry of complex-organized molecular and nanosized systems, including polymer-metal complexes; the surface of doped oxide semiconductors. He is an expert in structural, absorptive, catalytic and photocatalytic properties, in structural organization and dynamic features of ionic liquids, in magnetic interactions between paramagnetic centers. The author or co-author of 3 books, over 200 articles and reviews in scientific journals and books. He is an actual member of the International EPR/ESR Society, European Society on Quantum Solar Energy Conversion, Moscow House of Scientists, of the Board of Moscow Physical Society.",institutionString:null,institution:{name:"Semenov Institute of Chemical Physics",country:{name:"Russia"}}},{id:"62389",title:"PhD.",name:"Ali Demir",middleName:null,surname:"Sezer",slug:"ali-demir-sezer",fullName:"Ali Demir Sezer",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/62389/images/3413_n.jpg",biography:"Dr. Ali Demir Sezer has a Ph.D. from Pharmaceutical Biotechnology at the Faculty of Pharmacy, University of Marmara (Turkey). He is the member of many Pharmaceutical Associations and acts as a reviewer of scientific journals and European projects under different research areas such as: drug delivery systems, nanotechnology and pharmaceutical biotechnology. Dr. Sezer is the author of many scientific publications in peer-reviewed journals and poster communications. Focus of his research activity is drug delivery, physico-chemical characterization and biological evaluation of biopolymers micro and nanoparticles as modified drug delivery system, and colloidal drug carriers (liposomes, nanoparticles etc.).",institutionString:null,institution:{name:"Marmara University",country:{name:"Turkey"}}},{id:"61051",title:"Prof.",name:"Andrea",middleName:null,surname:"Natale",slug:"andrea-natale",fullName:"Andrea Natale",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:null},{id:"100762",title:"Prof.",name:"Andrea",middleName:null,surname:"Natale",slug:"andrea-natale",fullName:"Andrea Natale",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:{name:"St David's Medical Center",country:{name:"United States of America"}}},{id:"107416",title:"Dr.",name:"Andrea",middleName:null,surname:"Natale",slug:"andrea-natale",fullName:"Andrea Natale",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:{name:"Texas Cardiac Arrhythmia",country:{name:"United States of America"}}},{id:"64434",title:"Dr.",name:"Angkoon",middleName:null,surname:"Phinyomark",slug:"angkoon-phinyomark",fullName:"Angkoon Phinyomark",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/64434/images/2619_n.jpg",biography:"My name is Angkoon Phinyomark. I received a B.Eng. degree in Computer Engineering with First Class Honors in 2008 from Prince of Songkla University, Songkhla, Thailand, where I received a Ph.D. degree in Electrical Engineering. My research interests are primarily in the area of biomedical signal processing and classification notably EMG (electromyography signal), EOG (electrooculography signal), and EEG (electroencephalography signal), image analysis notably breast cancer analysis and optical coherence tomography, and rehabilitation engineering. I became a student member of IEEE in 2008. During October 2011-March 2012, I had worked at School of Computer Science and Electronic Engineering, University of Essex, Colchester, Essex, United Kingdom. In addition, during a B.Eng. I had been a visiting research student at Faculty of Computer Science, University of Murcia, Murcia, Spain for three months.\n\nI have published over 40 papers during 5 years in refereed journals, books, and conference proceedings in the areas of electro-physiological signals processing and classification, notably EMG and EOG signals, fractal analysis, wavelet analysis, texture analysis, feature extraction and machine learning algorithms, and assistive and rehabilitative devices. I have several computer programming language certificates, i.e. Sun Certified Programmer for the Java 2 Platform 1.4 (SCJP), Microsoft Certified Professional Developer, Web Developer (MCPD), Microsoft Certified Technology Specialist, .NET Framework 2.0 Web (MCTS). I am a Reviewer for several refereed journals and international conferences, such as IEEE Transactions on Biomedical Engineering, IEEE Transactions on Industrial Electronics, Optic Letters, Measurement Science Review, and also a member of the International Advisory Committee for 2012 IEEE Business Engineering and Industrial Applications and 2012 IEEE Symposium on Business, Engineering and Industrial Applications.",institutionString:null,institution:{name:"Joseph Fourier University",country:{name:"France"}}},{id:"55578",title:"Dr.",name:"Antonio",middleName:null,surname:"Jurado-Navas",slug:"antonio-jurado-navas",fullName:"Antonio Jurado-Navas",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/55578/images/4574_n.png",biography:"Antonio Jurado-Navas received the M.S. degree (2002) and the Ph.D. degree (2009) in Telecommunication Engineering, both from the University of Málaga (Spain). He first worked as a consultant at Vodafone-Spain. From 2004 to 2011, he was a Research Assistant with the Communications Engineering Department at the University of Málaga. In 2011, he became an Assistant Professor in the same department. From 2012 to 2015, he was with Ericsson Spain, where he was working on geo-location\ntools for third generation mobile networks. Since 2015, he is a Marie-Curie fellow at the Denmark Technical University. His current research interests include the areas of mobile communication systems and channel modeling in addition to atmospheric optical communications, adaptive optics and statistics",institutionString:null,institution:{name:"University of Malaga",country:{name:"Spain"}}}],filtersByRegion:[{group:"region",caption:"North America",value:1,count:5816},{group:"region",caption:"Middle and South America",value:2,count:5281},{group:"region",caption:"Africa",value:3,count:1754},{group:"region",caption:"Asia",value:4,count:10511},{group:"region",caption:"Australia and Oceania",value:5,count:906},{group:"region",caption:"Europe",value:6,count:15912}],offset:12,limit:12,total:119060},chapterEmbeded:{data:{}},editorApplication:{success:null,errors:{}},ofsBooks:{filterParams:{topicId:"21"},books:[{type:"book",id:"10671",title:"Connected Adolescence",subtitle:null,isOpenForSubmission:!0,hash:"f005179bb7f6cd7c531a00cd8da18eaa",slug:null,bookSignature:"Prof. Massimo Ingrassia and Prof. Loredana Benedetto",coverURL:"https://cdn.intechopen.com/books/images_new/10671.jpg",editedByType:null,editors:[{id:"193901",title:"Prof.",name:"Massimo",surname:"Ingrassia",slug:"massimo-ingrassia",fullName:"Massimo Ingrassia"}],productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10814",title:"Anxiety, Uncertainty, and Resilience During the Pandemic Period - Anthropological and Psychological Perspectives",subtitle:null,isOpenForSubmission:!0,hash:"2db4d2a6638d2c66f7a5741d0f8fe4ae",slug:null,bookSignature:"Prof. Fabio Gabrielli and Dr. Floriana Irtelli",coverURL:"https://cdn.intechopen.com/books/images_new/10814.jpg",editedByType:null,editors:[{id:"259407",title:"Prof.",name:"Fabio",surname:"Gabrielli",slug:"fabio-gabrielli",fullName:"Fabio Gabrielli"}],productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10908",title:"Decision Making",subtitle:null,isOpenForSubmission:!0,hash:"126486f7f91e18e2e3539a32c38be7b1",slug:null,bookSignature:"Prof. Fausto Pedro García Márquez",coverURL:"https://cdn.intechopen.com/books/images_new/10908.jpg",editedByType:null,editors:[{id:"22844",title:"Prof.",name:"Fausto Pedro",surname:"García Márquez",slug:"fausto-pedro-garcia-marquez",fullName:"Fausto Pedro García Márquez"}],productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10909",title:"Psychometrics",subtitle:null,isOpenForSubmission:!0,hash:"51388e9ab6c536936b8da4f9c226252e",slug:null,bookSignature:"",coverURL:"https://cdn.intechopen.com/books/images_new/10909.jpg",editedByType:null,editors:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10910",title:"Learning Disabilities",subtitle:null,isOpenForSubmission:!0,hash:"8350f78c26c99f01f8130f772475504e",slug:null,bookSignature:"",coverURL:"https://cdn.intechopen.com/books/images_new/10910.jpg",editedByType:null,editors:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10981",title:"Sport Psychology in Sports, Exercise and Physical Activity",subtitle:null,isOpenForSubmission:!0,hash:"5214c44bdc42978449de0751ca364684",slug:null,bookSignature:"Ph.D. Hilde G. Nielsen",coverURL:"https://cdn.intechopen.com/books/images_new/10981.jpg",editedByType:null,editors:[{id:"158692",title:"Ph.D.",name:"Hilde G.",surname:"Nielsen",slug:"hilde-g.-nielsen",fullName:"Hilde G. Nielsen"}],productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}}],filtersByTopic:[{group:"topic",caption:"Agricultural and Biological Sciences",value:5,count:25},{group:"topic",caption:"Biochemistry, Genetics and Molecular Biology",value:6,count:7},{group:"topic",caption:"Business, Management and Economics",value:7,count:3},{group:"topic",caption:"Chemistry",value:8,count:11},{group:"topic",caption:"Computer and Information Science",value:9,count:9},{group:"topic",caption:"Earth and Planetary Sciences",value:10,count:9},{group:"topic",caption:"Engineering",value:11,count:25},{group:"topic",caption:"Environmental Sciences",value:12,count:3},{group:"topic",caption:"Immunology and Microbiology",value:13,count:4},{group:"topic",caption:"Materials Science",value:14,count:7},{group:"topic",caption:"Mathematics",value:15,count:2},{group:"topic",caption:"Medicine",value:16,count:44},{group:"topic",caption:"Neuroscience",value:18,count:3},{group:"topic",caption:"Pharmacology, Toxicology and Pharmaceutical Science",value:19,count:3},{group:"topic",caption:"Physics",value:20,count:4},{group:"topic",caption:"Psychology",value:21,count:4},{group:"topic",caption:"Robotics",value:22,count:1},{group:"topic",caption:"Social Sciences",value:23,count:3},{group:"topic",caption:"Technology",value:24,count:1},{group:"topic",caption:"Veterinary Medicine and Science",value:25,count:2}],offset:12,limit:12,total:6},popularBooks:{featuredBooks:[{type:"book",id:"8472",title:"Bioactive Compounds in Nutraceutical and Functional Food for Good Human Health",subtitle:null,isOpenForSubmission:!1,hash:"8855452919b8495810ef8e88641feb20",slug:"bioactive-compounds-in-nutraceutical-and-functional-food-for-good-human-health",bookSignature:"Kavita Sharma, Kanchan Mishra, Kula Kamal Senapati and Corina Danciu",coverURL:"https://cdn.intechopen.com/books/images_new/8472.jpg",editors:[{id:"197731",title:"Dr.",name:"Kavita",middleName:null,surname:"Sharma",slug:"kavita-sharma",fullName:"Kavita Sharma"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9685",title:"Agroecosystems",subtitle:"Very Complex Environmental Systems",isOpenForSubmission:!1,hash:"c44f7b43a9f9610c243dc32300d37df6",slug:"agroecosystems-very-complex-environmental-systems",bookSignature:"Marcelo L. Larramendy and Sonia Soloneski",coverURL:"https://cdn.intechopen.com/books/images_new/9685.jpg",editors:[{id:"14764",title:"Dr.",name:"Marcelo L.",middleName:null,surname:"Larramendy",slug:"marcelo-l.-larramendy",fullName:"Marcelo L. Larramendy"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8564",title:"Cell Interaction",subtitle:"Molecular and Immunological Basis for Disease Management",isOpenForSubmission:!1,hash:"98d7f080d80524285f091e72a8e92a6d",slug:"cell-interaction-molecular-and-immunological-basis-for-disease-management",bookSignature:"Bhawana Singh",coverURL:"https://cdn.intechopen.com/books/images_new/8564.jpg",editors:[{id:"315192",title:"Dr.",name:"Bhawana",middleName:null,surname:"Singh",slug:"bhawana-singh",fullName:"Bhawana Singh"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9629",title:"Electroencephalography",subtitle:"From Basic Research to Clinical Applications",isOpenForSubmission:!1,hash:"8147834b6c6deeeec40f407c71ad60b4",slug:"electroencephalography-from-basic-research-to-clinical-applications",bookSignature:"Hideki Nakano",coverURL:"https://cdn.intechopen.com/books/images_new/9629.jpg",editors:[{id:"196461",title:"Prof.",name:"Hideki",middleName:null,surname:"Nakano",slug:"hideki-nakano",fullName:"Hideki Nakano"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8760",title:"Structure Topology and Symplectic Geometry",subtitle:null,isOpenForSubmission:!1,hash:"8974840985ec3652492c83e20233bf02",slug:"structure-topology-and-symplectic-geometry",bookSignature:"Kamal Shah and Min Lei",coverURL:"https://cdn.intechopen.com/books/images_new/8760.jpg",editors:[{id:"231748",title:"Dr.",name:"Kamal",middleName:null,surname:"Shah",slug:"kamal-shah",fullName:"Kamal Shah"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9161",title:"Frailty in the Elderly",subtitle:"Understanding and Managing Complexity",isOpenForSubmission:!1,hash:"a4f0f2fade8fb8ba35c405f5ad31a823",slug:"frailty-in-the-elderly-understanding-and-managing-complexity",bookSignature:"Sara Palermo",coverURL:"https://cdn.intechopen.com/books/images_new/9161.jpg",editors:[{id:"233998",title:"Ph.D.",name:"Sara",middleName:null,surname:"Palermo",slug:"sara-palermo",fullName:"Sara Palermo"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8445",title:"Dam Engineering",subtitle:"Recent Advances in Design and Analysis",isOpenForSubmission:!1,hash:"a7e4d2ecbc65d78fa7582e0d2e143906",slug:"dam-engineering-recent-advances-in-design-and-analysis",bookSignature:"Zhongzhi Fu and Erich Bauer",coverURL:"https://cdn.intechopen.com/books/images_new/8445.jpg",editors:[{id:"249577",title:"Dr.",name:"Zhongzhi",middleName:null,surname:"Fu",slug:"zhongzhi-fu",fullName:"Zhongzhi Fu"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9385",title:"Renewable Energy",subtitle:"Technologies and Applications",isOpenForSubmission:!1,hash:"a6b446d19166f17f313008e6c056f3d8",slug:"renewable-energy-technologies-and-applications",bookSignature:"Tolga Taner, Archana Tiwari and Taha Selim Ustun",coverURL:"https://cdn.intechopen.com/books/images_new/9385.jpg",editors:[{id:"197240",title:"Associate Prof.",name:"Tolga",middleName:null,surname:"Taner",slug:"tolga-taner",fullName:"Tolga Taner"}],equalEditorOne:{id:"186791",title:"Dr.",name:"Archana",middleName:null,surname:"Tiwari",slug:"archana-tiwari",fullName:"Archana Tiwari",profilePictureURL:"https://mts.intechopen.com/storage/users/186791/images/system/186791.jpg",biography:"Dr. Archana Tiwari is Associate Professor at Amity University, India. Her research interests include renewable sources of energy from microalgae and further utilizing the residual biomass for the generation of value-added products, bioremediation through microalgae and microbial consortium, antioxidative enzymes and stress, and nutraceuticals from microalgae. She has been working on algal biotechnology for the last two decades. She has published her research in many international journals and has authored many books and chapters with renowned publishing houses. She has also delivered talks as an invited speaker at many national and international conferences. Dr. Tiwari is the recipient of several awards including Researcher of the Year and Distinguished Scientist.",institutionString:"Amity University",position:null,outsideEditionCount:0,totalCites:0,totalAuthoredChapters:"3",totalChapterViews:"0",totalEditedBooks:"1",institution:{name:"Amity University",institutionURL:null,country:{name:"India"}}},equalEditorTwo:{id:"197609",title:"Prof.",name:"Taha Selim",middleName:null,surname:"Ustun",slug:"taha-selim-ustun",fullName:"Taha Selim Ustun",profilePictureURL:"https://mts.intechopen.com/storage/users/197609/images/system/197609.jpeg",biography:"Dr. Taha Selim Ustun received a Ph.D. in Electrical Engineering from Victoria University, Melbourne, Australia. He is a researcher with the Fukushima Renewable Energy Institute, AIST (FREA), where he leads the Smart Grid Cybersecurity Laboratory. Prior to that, he was a faculty member with the School of Electrical and Computer Engineering, Carnegie Mellon University, Pittsburgh, PA, USA. His current research interests include power systems protection, communication in power networks, distributed generation, microgrids, electric vehicle integration, and cybersecurity in smart grids. He serves on the editorial boards of IEEE Access, IEEE Transactions on Industrial Informatics, Energies, Electronics, Electricity, World Electric Vehicle and Information journals. Dr. Ustun is a member of the IEEE 2004 and 2800, IEC Renewable Energy Management WG 8, and IEC TC 57 WG17. He has been invited to run specialist courses in Africa, India, and China. He has delivered talks for the Qatar Foundation, the World Energy Council, the Waterloo Global Science Initiative, and the European Union Energy Initiative (EUEI). His research has attracted funding from prestigious programs in Japan, Australia, the European Union, and North America.",institutionString:"Fukushima Renewable Energy Institute, AIST (FREA)",position:null,outsideEditionCount:0,totalCites:0,totalAuthoredChapters:"1",totalChapterViews:"0",totalEditedBooks:"0",institution:{name:"National Institute of Advanced Industrial Science and Technology",institutionURL:null,country:{name:"Japan"}}},equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8937",title:"Soil Moisture Importance",subtitle:null,isOpenForSubmission:!1,hash:"3951728ace7f135451d66b72e9908b47",slug:"soil-moisture-importance",bookSignature:"Ram Swaroop Meena and Rahul Datta",coverURL:"https://cdn.intechopen.com/books/images_new/8937.jpg",editors:[{id:"313528",title:"Associate Prof.",name:"Ram Swaroop",middleName:null,surname:"Meena",slug:"ram-swaroop-meena",fullName:"Ram Swaroop Meena"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"7031",title:"Liver Pathology",subtitle:null,isOpenForSubmission:!1,hash:"631321b0565459ed0175917f1c8c727f",slug:"liver-pathology",bookSignature:"Vijay Gayam and Omer Engin",coverURL:"https://cdn.intechopen.com/books/images_new/7031.jpg",editors:[{id:"273100",title:"Dr.",name:"Vijay",middleName:null,surname:"Gayam",slug:"vijay-gayam",fullName:"Vijay Gayam"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8158",title:"Veganism",subtitle:"a Fashion Trend or Food as a Medicine",isOpenForSubmission:!1,hash:"d8e51fc25a379e5b92a270addbb4351d",slug:"veganism-a-fashion-trend-or-food-as-a-medicine",bookSignature:"Miljana Z. Jovandaric",coverURL:"https://cdn.intechopen.com/books/images_new/8158.jpg",editors:[{id:"268043",title:"Dr.",name:"Miljana Z.",middleName:"Z",surname:"Jovandaric",slug:"miljana-z.-jovandaric",fullName:"Miljana Z. Jovandaric"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"2160",title:"MATLAB",subtitle:"A Fundamental Tool for Scientific Computing and Engineering Applications - Volume 1",isOpenForSubmission:!1,hash:"dd9c658341fbd264ed4f8d9e6aa8ca29",slug:"matlab-a-fundamental-tool-for-scientific-computing-and-engineering-applications-volume-1",bookSignature:"Vasilios N. Katsikis",coverURL:"https://cdn.intechopen.com/books/images_new/2160.jpg",editors:[{id:"12289",title:"Prof.",name:"Vasilios",middleName:"N.",surname:"Katsikis",slug:"vasilios-katsikis",fullName:"Vasilios Katsikis"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}}],offset:12,limit:12,total:5315},hotBookTopics:{hotBooks:[],offset:0,limit:12,total:null},publish:{},publishingProposal:{success:null,errors:{}},books:{featuredBooks:[{type:"book",id:"8472",title:"Bioactive Compounds in Nutraceutical and Functional Food for Good Human Health",subtitle:null,isOpenForSubmission:!1,hash:"8855452919b8495810ef8e88641feb20",slug:"bioactive-compounds-in-nutraceutical-and-functional-food-for-good-human-health",bookSignature:"Kavita Sharma, Kanchan Mishra, Kula Kamal Senapati and Corina Danciu",coverURL:"https://cdn.intechopen.com/books/images_new/8472.jpg",editors:[{id:"197731",title:"Dr.",name:"Kavita",middleName:null,surname:"Sharma",slug:"kavita-sharma",fullName:"Kavita Sharma"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9685",title:"Agroecosystems",subtitle:"Very Complex Environmental Systems",isOpenForSubmission:!1,hash:"c44f7b43a9f9610c243dc32300d37df6",slug:"agroecosystems-very-complex-environmental-systems",bookSignature:"Marcelo L. Larramendy and Sonia Soloneski",coverURL:"https://cdn.intechopen.com/books/images_new/9685.jpg",editors:[{id:"14764",title:"Dr.",name:"Marcelo L.",middleName:null,surname:"Larramendy",slug:"marcelo-l.-larramendy",fullName:"Marcelo L. Larramendy"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8564",title:"Cell Interaction",subtitle:"Molecular and Immunological Basis for Disease Management",isOpenForSubmission:!1,hash:"98d7f080d80524285f091e72a8e92a6d",slug:"cell-interaction-molecular-and-immunological-basis-for-disease-management",bookSignature:"Bhawana Singh",coverURL:"https://cdn.intechopen.com/books/images_new/8564.jpg",editors:[{id:"315192",title:"Dr.",name:"Bhawana",middleName:null,surname:"Singh",slug:"bhawana-singh",fullName:"Bhawana Singh"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9629",title:"Electroencephalography",subtitle:"From Basic Research to Clinical Applications",isOpenForSubmission:!1,hash:"8147834b6c6deeeec40f407c71ad60b4",slug:"electroencephalography-from-basic-research-to-clinical-applications",bookSignature:"Hideki Nakano",coverURL:"https://cdn.intechopen.com/books/images_new/9629.jpg",editors:[{id:"196461",title:"Prof.",name:"Hideki",middleName:null,surname:"Nakano",slug:"hideki-nakano",fullName:"Hideki Nakano"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8760",title:"Structure Topology and Symplectic Geometry",subtitle:null,isOpenForSubmission:!1,hash:"8974840985ec3652492c83e20233bf02",slug:"structure-topology-and-symplectic-geometry",bookSignature:"Kamal Shah and Min Lei",coverURL:"https://cdn.intechopen.com/books/images_new/8760.jpg",editors:[{id:"231748",title:"Dr.",name:"Kamal",middleName:null,surname:"Shah",slug:"kamal-shah",fullName:"Kamal Shah"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9161",title:"Frailty in the Elderly",subtitle:"Understanding and Managing Complexity",isOpenForSubmission:!1,hash:"a4f0f2fade8fb8ba35c405f5ad31a823",slug:"frailty-in-the-elderly-understanding-and-managing-complexity",bookSignature:"Sara Palermo",coverURL:"https://cdn.intechopen.com/books/images_new/9161.jpg",editors:[{id:"233998",title:"Ph.D.",name:"Sara",middleName:null,surname:"Palermo",slug:"sara-palermo",fullName:"Sara Palermo"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8445",title:"Dam Engineering",subtitle:"Recent Advances in Design and Analysis",isOpenForSubmission:!1,hash:"a7e4d2ecbc65d78fa7582e0d2e143906",slug:"dam-engineering-recent-advances-in-design-and-analysis",bookSignature:"Zhongzhi Fu and Erich Bauer",coverURL:"https://cdn.intechopen.com/books/images_new/8445.jpg",editors:[{id:"249577",title:"Dr.",name:"Zhongzhi",middleName:null,surname:"Fu",slug:"zhongzhi-fu",fullName:"Zhongzhi Fu"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9385",title:"Renewable Energy",subtitle:"Technologies and Applications",isOpenForSubmission:!1,hash:"a6b446d19166f17f313008e6c056f3d8",slug:"renewable-energy-technologies-and-applications",bookSignature:"Tolga Taner, Archana Tiwari and Taha Selim Ustun",coverURL:"https://cdn.intechopen.com/books/images_new/9385.jpg",editors:[{id:"197240",title:"Associate Prof.",name:"Tolga",middleName:null,surname:"Taner",slug:"tolga-taner",fullName:"Tolga Taner"}],equalEditorOne:{id:"186791",title:"Dr.",name:"Archana",middleName:null,surname:"Tiwari",slug:"archana-tiwari",fullName:"Archana Tiwari",profilePictureURL:"https://mts.intechopen.com/storage/users/186791/images/system/186791.jpg",biography:"Dr. Archana Tiwari is Associate Professor at Amity University, India. Her research interests include renewable sources of energy from microalgae and further utilizing the residual biomass for the generation of value-added products, bioremediation through microalgae and microbial consortium, antioxidative enzymes and stress, and nutraceuticals from microalgae. She has been working on algal biotechnology for the last two decades. She has published her research in many international journals and has authored many books and chapters with renowned publishing houses. She has also delivered talks as an invited speaker at many national and international conferences. Dr. Tiwari is the recipient of several awards including Researcher of the Year and Distinguished Scientist.",institutionString:"Amity University",position:null,outsideEditionCount:0,totalCites:0,totalAuthoredChapters:"3",totalChapterViews:"0",totalEditedBooks:"1",institution:{name:"Amity University",institutionURL:null,country:{name:"India"}}},equalEditorTwo:{id:"197609",title:"Prof.",name:"Taha Selim",middleName:null,surname:"Ustun",slug:"taha-selim-ustun",fullName:"Taha Selim Ustun",profilePictureURL:"https://mts.intechopen.com/storage/users/197609/images/system/197609.jpeg",biography:"Dr. Taha Selim Ustun received a Ph.D. in Electrical Engineering from Victoria University, Melbourne, Australia. He is a researcher with the Fukushima Renewable Energy Institute, AIST (FREA), where he leads the Smart Grid Cybersecurity Laboratory. Prior to that, he was a faculty member with the School of Electrical and Computer Engineering, Carnegie Mellon University, Pittsburgh, PA, USA. His current research interests include power systems protection, communication in power networks, distributed generation, microgrids, electric vehicle integration, and cybersecurity in smart grids. He serves on the editorial boards of IEEE Access, IEEE Transactions on Industrial Informatics, Energies, Electronics, Electricity, World Electric Vehicle and Information journals. Dr. Ustun is a member of the IEEE 2004 and 2800, IEC Renewable Energy Management WG 8, and IEC TC 57 WG17. He has been invited to run specialist courses in Africa, India, and China. He has delivered talks for the Qatar Foundation, the World Energy Council, the Waterloo Global Science Initiative, and the European Union Energy Initiative (EUEI). His research has attracted funding from prestigious programs in Japan, Australia, the European Union, and North America.",institutionString:"Fukushima Renewable Energy Institute, AIST (FREA)",position:null,outsideEditionCount:0,totalCites:0,totalAuthoredChapters:"1",totalChapterViews:"0",totalEditedBooks:"0",institution:{name:"National Institute of Advanced Industrial Science and Technology",institutionURL:null,country:{name:"Japan"}}},equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8937",title:"Soil Moisture Importance",subtitle:null,isOpenForSubmission:!1,hash:"3951728ace7f135451d66b72e9908b47",slug:"soil-moisture-importance",bookSignature:"Ram Swaroop Meena and Rahul Datta",coverURL:"https://cdn.intechopen.com/books/images_new/8937.jpg",editors:[{id:"313528",title:"Associate Prof.",name:"Ram Swaroop",middleName:null,surname:"Meena",slug:"ram-swaroop-meena",fullName:"Ram Swaroop Meena"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"7031",title:"Liver Pathology",subtitle:null,isOpenForSubmission:!1,hash:"631321b0565459ed0175917f1c8c727f",slug:"liver-pathology",bookSignature:"Vijay Gayam and Omer Engin",coverURL:"https://cdn.intechopen.com/books/images_new/7031.jpg",editors:[{id:"273100",title:"Dr.",name:"Vijay",middleName:null,surname:"Gayam",slug:"vijay-gayam",fullName:"Vijay Gayam"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}}],latestBooks:[{type:"book",id:"8472",title:"Bioactive Compounds in Nutraceutical and Functional Food for Good Human Health",subtitle:null,isOpenForSubmission:!1,hash:"8855452919b8495810ef8e88641feb20",slug:"bioactive-compounds-in-nutraceutical-and-functional-food-for-good-human-health",bookSignature:"Kavita Sharma, Kanchan Mishra, Kula Kamal Senapati and Corina Danciu",coverURL:"https://cdn.intechopen.com/books/images_new/8472.jpg",editedByType:"Edited by",editors:[{id:"197731",title:"Dr.",name:"Kavita",middleName:null,surname:"Sharma",slug:"kavita-sharma",fullName:"Kavita Sharma"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"8760",title:"Structure Topology and Symplectic Geometry",subtitle:null,isOpenForSubmission:!1,hash:"8974840985ec3652492c83e20233bf02",slug:"structure-topology-and-symplectic-geometry",bookSignature:"Kamal Shah and Min Lei",coverURL:"https://cdn.intechopen.com/books/images_new/8760.jpg",editedByType:"Edited by",editors:[{id:"231748",title:"Dr.",name:"Kamal",middleName:null,surname:"Shah",slug:"kamal-shah",fullName:"Kamal Shah"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9536",title:"Education at the Intersection of Globalization and Technology",subtitle:null,isOpenForSubmission:!1,hash:"0cf6891060eb438d975d250e8b127ed6",slug:"education-at-the-intersection-of-globalization-and-technology",bookSignature:"Sharon Waller, Lee Waller, Vongai Mpofu and Mercy Kurebwa",coverURL:"https://cdn.intechopen.com/books/images_new/9536.jpg",editedByType:"Edited by",editors:[{id:"263302",title:"Dr.",name:"Sharon",middleName:null,surname:"Waller",slug:"sharon-waller",fullName:"Sharon Waller"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"8564",title:"Cell Interaction",subtitle:"Molecular and Immunological Basis for Disease Management",isOpenForSubmission:!1,hash:"98d7f080d80524285f091e72a8e92a6d",slug:"cell-interaction-molecular-and-immunological-basis-for-disease-management",bookSignature:"Bhawana Singh",coverURL:"https://cdn.intechopen.com/books/images_new/8564.jpg",editedByType:"Edited by",editors:[{id:"315192",title:"Dr.",name:"Bhawana",middleName:null,surname:"Singh",slug:"bhawana-singh",fullName:"Bhawana Singh"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9629",title:"Electroencephalography",subtitle:"From Basic Research to Clinical Applications",isOpenForSubmission:!1,hash:"8147834b6c6deeeec40f407c71ad60b4",slug:"electroencephalography-from-basic-research-to-clinical-applications",bookSignature:"Hideki Nakano",coverURL:"https://cdn.intechopen.com/books/images_new/9629.jpg",editedByType:"Edited by",editors:[{id:"196461",title:"Prof.",name:"Hideki",middleName:null,surname:"Nakano",slug:"hideki-nakano",fullName:"Hideki Nakano"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9685",title:"Agroecosystems",subtitle:"Very Complex Environmental Systems",isOpenForSubmission:!1,hash:"c44f7b43a9f9610c243dc32300d37df6",slug:"agroecosystems-very-complex-environmental-systems",bookSignature:"Marcelo L. Larramendy and Sonia Soloneski",coverURL:"https://cdn.intechopen.com/books/images_new/9685.jpg",editedByType:"Edited by",editors:[{id:"14764",title:"Dr.",name:"Marcelo L.",middleName:null,surname:"Larramendy",slug:"marcelo-l.-larramendy",fullName:"Marcelo L. Larramendy"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9524",title:"Organ Donation and Transplantation",subtitle:null,isOpenForSubmission:!1,hash:"6ef47e03cd4e6476946fc28ca51de825",slug:"organ-donation-and-transplantation",bookSignature:"Vassil Mihaylov",coverURL:"https://cdn.intechopen.com/books/images_new/9524.jpg",editedByType:"Edited by",editors:[{id:"313113",title:"Associate Prof.",name:"Vassil",middleName:null,surname:"Mihaylov",slug:"vassil-mihaylov",fullName:"Vassil Mihaylov"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9280",title:"Underwater Work",subtitle:null,isOpenForSubmission:!1,hash:"647b4270d937deae4a82f5702d1959ec",slug:"underwater-work",bookSignature:"Sérgio António Neves Lousada",coverURL:"https://cdn.intechopen.com/books/images_new/9280.jpg",editedByType:"Edited by",editors:[{id:"248645",title:"Dr.",name:"Sérgio António",middleName:null,surname:"Neves Lousada",slug:"sergio-antonio-neves-lousada",fullName:"Sérgio António Neves Lousada"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9161",title:"Frailty in the Elderly",subtitle:"Understanding and Managing Complexity",isOpenForSubmission:!1,hash:"a4f0f2fade8fb8ba35c405f5ad31a823",slug:"frailty-in-the-elderly-understanding-and-managing-complexity",bookSignature:"Sara Palermo",coverURL:"https://cdn.intechopen.com/books/images_new/9161.jpg",editedByType:"Edited by",editors:[{id:"233998",title:"Ph.D.",name:"Sara",middleName:null,surname:"Palermo",slug:"sara-palermo",fullName:"Sara Palermo"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"8158",title:"Veganism",subtitle:"a Fashion Trend or Food as a Medicine",isOpenForSubmission:!1,hash:"d8e51fc25a379e5b92a270addbb4351d",slug:"veganism-a-fashion-trend-or-food-as-a-medicine",bookSignature:"Miljana Z. Jovandaric",coverURL:"https://cdn.intechopen.com/books/images_new/8158.jpg",editedByType:"Edited by",editors:[{id:"268043",title:"Dr.",name:"Miljana Z.",middleName:"Z",surname:"Jovandaric",slug:"miljana-z.-jovandaric",fullName:"Miljana Z. Jovandaric"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}}]},subject:{topic:{id:"20",title:"Physics",slug:"physics",parent:{title:"Physical Sciences, Engineering and Technology",slug:"physical-sciences-engineering-and-technology"},numberOfBooks:143,numberOfAuthorsAndEditors:3401,numberOfWosCitations:3946,numberOfCrossrefCitations:1606,numberOfDimensionsCitations:3490,videoUrl:null,fallbackUrl:null,description:null},booksByTopicFilter:{topicSlug:"physics ",sort:"-publishedDate",limit:12,offset:0},booksByTopicCollection:[{type:"book",id:"9984",title:"Geophysics and Ocean Waves Studies",subtitle:null,isOpenForSubmission:!1,hash:"271d086381f9ba04162b0dc7cd57755f",slug:"geophysics-and-ocean-waves-studies",bookSignature:"Khalid S. Essa, Marcello Di Risio, Daniele Celli and Davide Pasquali",coverURL:"https://cdn.intechopen.com/books/images_new/9984.jpg",editedByType:"Edited by",editors:[{id:"102766",title:"Prof.",name:"Khalid S.",middleName:null,surname:"Essa",slug:"khalid-s.-essa",fullName:"Khalid S. Essa"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10042",title:"Noise and Environment",subtitle:null,isOpenForSubmission:!1,hash:"11e8fca2f0f623d87dfbc3cf2b185e0d",slug:"noise-and-environment",bookSignature:"Daniela Siano and Alice Elizabeth González",coverURL:"https://cdn.intechopen.com/books/images_new/10042.jpg",editedByType:"Edited by",editors:[{id:"9960",title:"Dr.",name:"Daniela",middleName:null,surname:"Siano",slug:"daniela-siano",fullName:"Daniela Siano"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10075",title:"Nonlinear Optics",subtitle:"From Solitons to Similaritons",isOpenForSubmission:!1,hash:"b034b2a060292c8511359aec0db1002c",slug:"nonlinear-optics-from-solitons-to-similaritons",bookSignature:"İlkay Bakırtaş and Nalan Antar",coverURL:"https://cdn.intechopen.com/books/images_new/10075.jpg",editedByType:"Edited by",editors:[{id:"186388",title:"Prof.",name:"İlkay",middleName:null,surname:"Bakırtaş",slug:"ilkay-bakirtas",fullName:"İlkay Bakırtaş"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"7769",title:"Medical Isotopes",subtitle:null,isOpenForSubmission:!1,hash:"f8d3c5a6c9a42398e56b4e82264753f7",slug:"medical-isotopes",bookSignature:"Syed Ali Raza Naqvi and Muhammad Babar Imrani",coverURL:"https://cdn.intechopen.com/books/images_new/7769.jpg",editedByType:"Edited by",editors:[{id:"259190",title:"Dr.",name:"Syed Ali Raza",middleName:null,surname:"Naqvi",slug:"syed-ali-raza-naqvi",fullName:"Syed Ali Raza Naqvi"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10074",title:"Recent Techniques and Applications in Ionizing Radiation Research",subtitle:null,isOpenForSubmission:!1,hash:"129deeec2186f6392f154ed41f64477a",slug:"recent-techniques-and-applications-in-ionizing-radiation-research",bookSignature:"Ahmed M. Maghraby and Basim Almayyahi",coverURL:"https://cdn.intechopen.com/books/images_new/10074.jpg",editedByType:"Edited by",editors:[{id:"102209",title:"Dr.",name:"Ahmed M.",middleName:null,surname:"Maghraby",slug:"ahmed-m.-maghraby",fullName:"Ahmed M. Maghraby"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"8679",title:"Inverse Heat Conduction and Heat Exchangers",subtitle:null,isOpenForSubmission:!1,hash:"a994b17ac471c6d414d63c74a7ab74de",slug:"inverse-heat-conduction-and-heat-exchangers",bookSignature:"Suvanjan Bhattacharya, Mohammad Moghimi Ardekani, Ranjib Biswas and R. C. Mehta",coverURL:"https://cdn.intechopen.com/books/images_new/8679.jpg",editedByType:"Edited by",editors:[{id:"233630",title:"Dr.",name:"Suvanjan",middleName:null,surname:"Bhattacharyya",slug:"suvanjan-bhattacharyya",fullName:"Suvanjan Bhattacharyya"}],equalEditorOne:{id:"56358",title:"Dr.",name:"R. C.",middleName:null,surname:"Mehta",slug:"r.-c.-mehta",fullName:"R. C. Mehta",profilePictureURL:"https://mts.intechopen.com/storage/users/56358/images/system/56358.jpeg",biography:"R. C. Mehta obtained his Ph.D. from the Indian Institute of Technology, Madras. He has worked as the Head of Aerodynamics\nDivision of Vikram Sarabhai Space Centre/Indian Space Research\nOrganization. He has participated in the design of launch and\nreentry vehicles. He has served as a Senior Fellow in the School\nof Mechanical and Aerospace Engineering at Nanyang Technological University, Singapore. He is the recipient of the Life Time\nAchievement Award from the Flow Physics Society of India. He is a senior member\nof AIAA. He has published over 120 papers in peer-reviewed national and international journals. He has published five chapters and co-authored two books. He is a\nreviewer for many international journals. He is presently Dean in the Noorul Islam\nCentre for Higher Education, Kumaracoil, India.",institutionString:"Noorul Islam University",position:null,outsideEditionCount:0,totalCites:0,totalAuthoredChapters:"5",totalChapterViews:"0",totalEditedBooks:"0",institution:{name:"Noorul Islam University",institutionURL:null,country:{name:"India"}}},equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"8490",title:"Selected Topics in Plasma Physics",subtitle:null,isOpenForSubmission:!1,hash:"0fe936bfad77ae70ad96c46de8b7730d",slug:"selected-topics-in-plasma-physics",bookSignature:"Sukhmander Singh",coverURL:"https://cdn.intechopen.com/books/images_new/8490.jpg",editedByType:"Edited by",editors:[{id:"282807",title:"Dr.",name:"Sukhmander",middleName:null,surname:"Singh",slug:"sukhmander-singh",fullName:"Sukhmander Singh"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9211",title:"Single Photon Manipulation",subtitle:null,isOpenForSubmission:!1,hash:"567ddcc14b68fa14e54df3bce2f51acc",slug:"single-photon-manipulation",bookSignature:"Keyu Xia",coverURL:"https://cdn.intechopen.com/books/images_new/9211.jpg",editedByType:"Edited by",editors:[{id:"210723",title:"Prof.",name:"Keyu",middleName:null,surname:"Xia",slug:"keyu-xia",fullName:"Keyu Xia"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10076",title:"Quantum Mechanics",subtitle:null,isOpenForSubmission:!1,hash:"78f2b316d6bb97464dbbf9b683164aff",slug:"quantum-mechanics",bookSignature:"Paul Bracken",coverURL:"https://cdn.intechopen.com/books/images_new/10076.jpg",editedByType:"Edited by",editors:[{id:"92883",title:"Prof.",name:"Paul",middleName:null,surname:"Bracken",slug:"paul-bracken",fullName:"Paul Bracken"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"7965",title:"Liquid Crystals and Display Technology",subtitle:null,isOpenForSubmission:!1,hash:"eb83772cea6200bdd685b8a1b93ee35d",slug:"liquid-crystals-and-display-technology",bookSignature:"Morteza Sasani Ghamsari and Irina Carlescu",coverURL:"https://cdn.intechopen.com/books/images_new/7965.jpg",editedByType:"Edited by",editors:[{id:"64949",title:"Prof.",name:"Morteza",middleName:null,surname:"Sasani Ghamsari",slug:"morteza-sasani-ghamsari",fullName:"Morteza Sasani Ghamsari"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9276",title:"Computational Fluid Dynamics Simulations",subtitle:null,isOpenForSubmission:!1,hash:"03a2501c6fc0ac90a8b328850b712da7",slug:"computational-fluid-dynamics-simulations",bookSignature:"Guozhao Ji and Jiujiang Zhu",coverURL:"https://cdn.intechopen.com/books/images_new/9276.jpg",editedByType:"Edited by",editors:[{id:"190139",title:"Dr.",name:"Guozhao",middleName:null,surname:"Ji",slug:"guozhao-ji",fullName:"Guozhao Ji"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10162",title:"A Diffusion Hydrodynamic Model",subtitle:null,isOpenForSubmission:!1,hash:"a8c90b653db4fa7a59132d39cca185d8",slug:"a-diffusion-hydrodynamic-model",bookSignature:"Theodore V. Hromadka II, Chung-Cheng Yen and Prasada Rao",coverURL:"https://cdn.intechopen.com/books/images_new/10162.jpg",editedByType:"Authored by",editors:[{id:"181008",title:"Dr.",name:"Theodore V.",middleName:"V.",surname:"Hromadka II",slug:"theodore-v.-hromadka-ii",fullName:"Theodore V. Hromadka II"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"4",chapterContentType:"compact",authoredCaption:"Authored by"}}],booksByTopicTotal:143,mostCitedChapters:[{id:"32842",doi:"10.5772/34901",title:"Sterilization by Gamma Irradiation",slug:"sterilization-by-gamma-irradiation",totalDownloads:73497,totalCrossrefCites:29,totalDimensionsCites:57,book:{slug:"gamma-radiation",title:"Gamma Radiation",fullTitle:"Gamma Radiation"},signatures:"Kátia Aparecida da Silva Aquino",authors:[{id:"102109",title:"Dr.",name:"Katia",middleName:"Aparecida Da S.",surname:"Aquino",slug:"katia-aquino",fullName:"Katia Aquino"}]},{id:"49652",doi:"10.5772/61720",title:"Sample Preparations for Scanning Electron Microscopy – Life Sciences",slug:"sample-preparations-for-scanning-electron-microscopy-life-sciences",totalDownloads:8108,totalCrossrefCites:24,totalDimensionsCites:53,book:{slug:"modern-electron-microscopy-in-physical-and-life-sciences",title:"Modern Electron Microscopy in Physical and Life Sciences",fullTitle:"Modern Electron Microscopy in Physical and Life Sciences"},signatures:"Mogana Das Murtey and Patchamuthu Ramasamy",authors:[{id:"176330",title:"Dr.",name:"Mogana",middleName:"Das",surname:"Murtey",slug:"mogana-murtey",fullName:"Mogana Murtey"},{id:"181159",title:"Mr.",name:"Patchamuthu",middleName:null,surname:"Ramasamy",slug:"patchamuthu-ramasamy",fullName:"Patchamuthu Ramasamy"}]},{id:"26791",doi:"10.5772/28067",title:"Optical Vortices in a Fiber: Mode Division Multiplexing and Multimode Self-Imaging",slug:"optical-vortices-in-a-fiber-mode-division-multiplexing-and-multimode-self-reproducing",totalDownloads:3944,totalCrossrefCites:18,totalDimensionsCites:39,book:{slug:"recent-progress-in-optical-fiber-research",title:"Recent Progress in Optical Fiber Research",fullTitle:"Recent Progress in Optical Fiber Research"},signatures:"S.N. Khonina, N.L. Kazanskiy and V.A. Soifer",authors:[{id:"72613",title:"Prof.",name:"Svetlana",middleName:null,surname:"Khonina",slug:"svetlana-khonina",fullName:"Svetlana Khonina"}]}],mostDownloadedChaptersLast30Days:[{id:"49537",title:"Electron Diffraction",slug:"electron-diffraction",totalDownloads:8444,totalCrossrefCites:6,totalDimensionsCites:21,book:{slug:"modern-electron-microscopy-in-physical-and-life-sciences",title:"Modern Electron Microscopy in Physical and Life Sciences",fullTitle:"Modern Electron Microscopy in Physical and Life Sciences"},signatures:"Mohsen Asadi Asadabad and Mohammad Jafari Eskandari",authors:[{id:"176352",title:"Dr.",name:"Mohsen",middleName:null,surname:"Asadi Asadabad",slug:"mohsen-asadi-asadabad",fullName:"Mohsen Asadi Asadabad"},{id:"177600",title:"Dr.",name:"Mohammad",middleName:null,surname:"Jafari Eskandari",slug:"mohammad-jafari-eskandari",fullName:"Mohammad Jafari Eskandari"}]},{id:"71638",title:"Plasma Antennas",slug:"plasma-antennas",totalDownloads:295,totalCrossrefCites:0,totalDimensionsCites:0,book:{slug:"selected-topics-in-plasma-physics",title:"Selected Topics in Plasma Physics",fullTitle:"Selected Topics in Plasma Physics"},signatures:"Theodore Anderson",authors:null},{id:"68746",title:"Optically Clear Adhesives for OLED",slug:"optically-clear-adhesives-for-oled",totalDownloads:1478,totalCrossrefCites:2,totalDimensionsCites:2,book:{slug:"luminescence-oled-technology-and-applications",title:"Luminescence",fullTitle:"Luminescence - OLED Technology and Applications"},signatures:"Joel T. Abrahamson, Hollis Z. Beagi, Fay Salmon and Christopher J. Campbell",authors:null},{id:"32842",title:"Sterilization by Gamma Irradiation",slug:"sterilization-by-gamma-irradiation",totalDownloads:73495,totalCrossrefCites:29,totalDimensionsCites:57,book:{slug:"gamma-radiation",title:"Gamma Radiation",fullTitle:"Gamma Radiation"},signatures:"Kátia Aparecida da Silva Aquino",authors:[{id:"102109",title:"Dr.",name:"Katia",middleName:"Aparecida Da S.",surname:"Aquino",slug:"katia-aquino",fullName:"Katia Aquino"}]},{id:"64351",title:"Progress in Plasma-Assisted Catalysis for Carbon Dioxide Reduction",slug:"progress-in-plasma-assisted-catalysis-for-carbon-dioxide-reduction",totalDownloads:1228,totalCrossrefCites:3,totalDimensionsCites:8,book:{slug:"plasma-chemistry-and-gas-conversion",title:"Plasma Chemistry and Gas Conversion",fullTitle:"Plasma Chemistry and Gas Conversion"},signatures:"Guoxing Chen, Ling Wang, Thomas Godfroid and Rony Snyders",authors:[{id:"199226",title:"Mr.",name:"Guoxing",middleName:null,surname:"Chen",slug:"guoxing-chen",fullName:"Guoxing Chen"}]},{id:"58243",title:"Multi-Core Optical Fibers: Theory, Applications and Opportunities",slug:"multi-core-optical-fibers-theory-applications-and-opportunities",totalDownloads:1697,totalCrossrefCites:2,totalDimensionsCites:3,book:{slug:"selected-topics-on-optical-fiber-technologies-and-applications",title:"Selected Topics on Optical Fiber Technologies and Applications",fullTitle:"Selected Topics on Optical Fiber Technologies and Applications"},signatures:"Andrés Macho Ortiz and Roberto Llorente Sáez",authors:[{id:"16540",title:"Dr.",name:"Roberto",middleName:null,surname:"Llorente",slug:"roberto-llorente",fullName:"Roberto Llorente"},{id:"207661",title:"Ph.D. Student",name:"Andres",middleName:null,surname:"Macho",slug:"andres-macho",fullName:"Andres Macho"}]},{id:"70578",title:"Gallium-68: Radiolabeling of Radiopharmaceuticals for PET Imaging - A Lot to Consider",slug:"gallium-68-radiolabeling-of-radiopharmaceuticals-for-pet-imaging-a-lot-to-consider",totalDownloads:701,totalCrossrefCites:3,totalDimensionsCites:3,book:{slug:"medical-isotopes",title:"Medical Isotopes",fullTitle:"Medical Isotopes"},signatures:"Michael Meisenheimer, Yury Saenko and Elisabeth Eppard",authors:null},{id:"49526",title:"Focused Ion Beams (FIB) — Novel Methodologies and Recent Applications for Multidisciplinary Sciences",slug:"focused-ion-beams-fib-novel-methodologies-and-recent-applications-for-multidisciplinary-sciences",totalDownloads:3432,totalCrossrefCites:1,totalDimensionsCites:5,book:{slug:"modern-electron-microscopy-in-physical-and-life-sciences",title:"Modern Electron Microscopy in Physical and Life Sciences",fullTitle:"Modern Electron Microscopy in Physical and Life Sciences"},signatures:"Meltem Sezen",authors:[{id:"176338",title:"Associate Prof.",name:"Meltem",middleName:null,surname:"Sezen",slug:"meltem-sezen",fullName:"Meltem Sezen"}]},{id:"32114",title:"Atmospheric Ionizing Radiation from Galactic and Solar Cosmic Rays",slug:"atmospheric-ionizing-radiation-from-galactic-and-solar-cosmic-rays",totalDownloads:3803,totalCrossrefCites:2,totalDimensionsCites:15,book:{slug:"current-topics-in-ionizing-radiation-research",title:"Current Topics in Ionizing Radiation Research",fullTitle:"Current Topics in Ionizing Radiation Research"},signatures:"Christopher J. Mertens, Brian T. Kress, Michael Wiltberger, W. Kent Tobiska, Barbara Grajewski and Xiaojing Xu",authors:[{id:"92275",title:"Dr.",name:"Christopher",middleName:null,surname:"Mertens",slug:"christopher-mertens",fullName:"Christopher Mertens"}]},{id:"49652",title:"Sample Preparations for Scanning Electron Microscopy – Life Sciences",slug:"sample-preparations-for-scanning-electron-microscopy-life-sciences",totalDownloads:8106,totalCrossrefCites:23,totalDimensionsCites:53,book:{slug:"modern-electron-microscopy-in-physical-and-life-sciences",title:"Modern Electron Microscopy in Physical and Life Sciences",fullTitle:"Modern Electron Microscopy in Physical and Life Sciences"},signatures:"Mogana Das Murtey and Patchamuthu Ramasamy",authors:[{id:"176330",title:"Dr.",name:"Mogana",middleName:"Das",surname:"Murtey",slug:"mogana-murtey",fullName:"Mogana Murtey"},{id:"181159",title:"Mr.",name:"Patchamuthu",middleName:null,surname:"Ramasamy",slug:"patchamuthu-ramasamy",fullName:"Patchamuthu Ramasamy"}]}],onlineFirstChaptersFilter:{topicSlug:"physics ",limit:3,offset:0},onlineFirstChaptersCollection:[{id:"76206",title:"Multiscale Modeling of Non-Isothermal Fluid Transport Involved in Drying Process of Porous Media",slug:"multiscale-modeling-of-non-isothermal-fluid-transport-involved-in-drying-process-of-porous-media",totalDownloads:0,totalDimensionsCites:0,doi:"10.5772/intechopen.97317",book:{title:"Porous Fluids - Advances in Fluid Flow and Transport phenomena in Porous Media"},signatures:"Kieu Hiep Le"},{id:"76039",title:"Stabilizing Zero-Field Skyrmions at Room-Temperature in Perpendicularly Magnetized Multilayers",slug:"stabilizing-zero-field-skyrmions-at-room-temperature-in-perpendicularly-magnetized-multilayers",totalDownloads:24,totalDimensionsCites:0,doi:"10.5772/intechopen.97179",book:{title:"Magnetic Skyrmions"},signatures:"Jeovani Brandão, Marcos Vinicius Puydinger dos Santos and Fanny Béron"},{id:"75997",title:"Entropy Based Biological Sequence Study",slug:"entropy-based-biological-sequence-study",totalDownloads:9,totalDimensionsCites:0,doi:"10.5772/intechopen.96615",book:{title:"Entropy and Exergy in Renewable Energy"},signatures:"Bimal Kumar Sarkar"}],onlineFirstChaptersTotal:18},preDownload:{success:null,errors:{}},aboutIntechopen:{},privacyPolicy:{},peerReviewing:{},howOpenAccessPublishingWithIntechopenWorks:{},sponsorshipBooks:{sponsorshipBooks:[{type:"book",id:"10176",title:"Microgrids and Local Energy Systems",subtitle:null,isOpenForSubmission:!0,hash:"c32b4a5351a88f263074b0d0ca813a9c",slug:null,bookSignature:"Prof. Nick Jenkins",coverURL:"https://cdn.intechopen.com/books/images_new/10176.jpg",editedByType:null,editors:[{id:"55219",title:"Prof.",name:"Nick",middleName:null,surname:"Jenkins",slug:"nick-jenkins",fullName:"Nick Jenkins"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}}],offset:8,limit:8,total:1},route:{name:"chapter.detail",path:"/books/current-issues-and-recent-advances-in-pacemaker-therapy/strategies-and-pacemaker-algorithms-for-avoidance-of-unnecessary-right-ventricular-stimulation",hash:"",query:{},params:{book:"current-issues-and-recent-advances-in-pacemaker-therapy",chapter:"strategies-and-pacemaker-algorithms-for-avoidance-of-unnecessary-right-ventricular-stimulation"},fullPath:"/books/current-issues-and-recent-advances-in-pacemaker-therapy/strategies-and-pacemaker-algorithms-for-avoidance-of-unnecessary-right-ventricular-stimulation",meta:{},from:{name:null,path:"/",hash:"",query:{},params:{},fullPath:"/",meta:{}}}},function(){var e;(e=document.currentScript||document.scripts[document.scripts.length-1]).parentNode.removeChild(e)}()