A flexible proximity sensor fully fabricated by inkjet printing is proposed in this paper. The flexible proximity sensor is composed of a ZnO layer sandwiched in between a flexible aluminum sheet and a web-shaped top electrode layer. The flexible aluminum sheet serves as the bottom electrode. The material of the top electrode layer is nano silver. Both the ZnO and top electrode layers are deposited by inkjet printing. The fully inkjet printing process possesses the advantages of direct patterning and low-cost. It does not require photolithography and etching processes since the pattern is directly printed on the flexible aluminum sheet. The prototype demonstrates that the presented flexible sensor is sensitive to the human body. It may be applied to proximity sensing or thermal eradiation sensing.

The purpose of this study is to optimize the design of a composite laminate hydrogen storage vessel for minimizing stress concentration. The optimum design of this study uses the finite-element method combined with a simplified conjugated gradient method (SCGM) and genetic algorithm (GA) to find the minimization of von Mises stress of the composite laminate hydrogen storage vessel. In this study, a composite laminate hydrogen storage vessel with an aluminum liner and a carbon fiber/epoxy layer are considered. The winding angle and thickness of the composite layer are proposed as optimal design variables. The comparison between SCGM and GA is discussed in order to obtain a promising optimum in design process. Through this optimization, the best possible combination of winding angle and thickness of composite layer has been obtained to obtain minimum possible stress concentration. Copyright © 2012 John Wiley & Sons, Ltd.

This paper proposes an original idea to minimize heat concentrations of high-power light-emitting diode (LED) arrays. The purpose of this paper is to investigate temperature distribution with and without an optimal process of high-power LED arrays by experiment and a numerical method in order to achieve an optimal design of LED arrays for thermal management. This paper develops an effective method to design each LED position for decreasing thermal concentrations in high-power LED arrays. In this paper, temperature profiles are measured by a thermal infrared camera and a thermocouple and compared with simulated results under different power. The optimal method is adopted by a simplified conjugate gradient method combined with a finite-element method. This method proves reliability of simulated results in advance. Through this optimal method, efficiency of heat removal will be enforced as an extra cooling device is added. The important part is that this optimal design will not affect brightness through an illumination analysis.