1. University of Hyogo,Graduate School of Engineering,Department of Mechanical Engineering,Hyogo,Japan,671-2280
2. Oita University,Faculty of Science and Technology,Department of Innovative Engineering,Oita,Japan,870-1192
3. Facultad de Ingeniería Universidad de Costa Rica,Instituto de Investigaciones en Ingeniería,San José,Costa Rica,11501-2060
4. Universitat Autònoma de Barcelona,Departament de Telecomunicació i d’Enginyeria de Sistemes,Barcelona,Spain,08193