1. Center for Bio-Artificial Muscle and Department of Biomedical Engineering; Hanyang University; Seoul 133-791 Korea
2. IT Fusion Technology Research Center and Department of IT Fusion Technology; Chosun University; Gwangju 501-759 Korea
3. Intelligent Polymer Research Institute; ARC Center of Excellence for Electromaterials Science; University of Wollongong; Wollongong NSW 2522 Australia
4. The Alan G. MacDiarmid NanoTech Institute; University of Texas at Dallas; Richardson TX 75083 USA