Jarumaneeroj C.,Chulalongkorn University |
Tashiro K.,Hisakata |
Tashiro K.,Chulalongkorn University |
Chirachanchai S.,Chulalongkorn University
Macromolecular Rapid Communications | Year: 2014
Sulfonated poly(ether ether ketone) (SPEEK) thin film performs reversible thermochromic property by developing the color to be yellowish at the temperature above 190 °C. The detailed analyses based on temperature-dependent techniques suggest the thermal treatment inducing the shifting of the hydrogen bond network between the sulfonated group and the hydrated water molecules to the π-π stacking among aromatic rings in SPEEK chains. Although it is general that the polymer chain packing is unfavorable at high temperature, the present work shows a good example that when the polymer chains can form specific molecular interaction, such as π-π stacking, even in harsh thermal treatment, a rearrangement will effectively occur, which leads to an external stimuli-responsive property. The present work shows the shifting from hydrogen bond network between sulfonic acid groups and water molecules to π-π stacking of aromatic rings as a key mechanism for reversible thermochromic properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Fujimoto I.,Hisakata |
Matsumoto T.,Hisakata |
de Silva P.R.S.,1 1 Hibarigaoka |
Kobayashi M.,Hisakata |
International Journal of Social Robotics | Year: 2011
In this paper, we report techniques for mimicking and evaluating the human motion in real time by a therapeutic humanoid robot to improve the imitation skill of children with autism. For realizing the mimicking technique, we propose a method of selecting key frames using a Q-Learning approach to remove the significant noises. Then, in order to evaluate human motion in real time, we introduce a method of cluster-based framework of Mixture Gaussian and an Expectation-Maximization algorithm using parameters which are converted by Principal Component Analysis. Practical experiments have been performed to test the interaction of children with autism with the robot and evaluate the possibility of improving their imitation skills by training them to perform specific tasks through a robot. © Springer Science & Business Media BV 2011.