Open access
Published: 10 September 2012
DOI: 10.5772/intechopen.84069
Published: 10 September 2012
© 2012 The Author(s). Licensee IntechOpen. This conference paper is distributed under the terms of the Creative Commons Attribution 3.0 License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.