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In this study, the fabrication method and structure of TCO-less dye-sensitized solar cells were investigated. The Ti electrode has replaced a transparent conductive oxide layer and was placed in a cell not to interrupt the light absorption of a TiO 2 photoelectrode. The porous Ti electrode was deposited on the TiO 2 layer using the electron-beam evaporation method. Therefore, a dye and an electrolyte were able to pass the Ti electrode. When the deposition time of Ti was increased, the sheet resistance of Ti was decreased. The solar cell properties were improved by reducing the sheet resistance of Ti electrode.

Currently, several types of atmospheric pressure plasma jet (APPJ) were introduced by many groups and widely used. In this study, we introduce a panel type APPJ which was developed using a plasma display panel (PDP) process. This device consists of facing glasses with barrier rib for feeding gas guide and electrode gap, where He gas flows between two dielectric-free Titanium metal electrodes with a voltage pulse shorter than 500 ns. He gas is injected with a gas flow rate of 0.1~5 liter per minutes through the electrodes that are exposed to the air and have a sub-millimeter gap. Unipolar DC pulse (25~50 kHz and 500~1000 V) or sinusoidal (50 kHz and 1 kVrms) power was applied to the electrode. The discharge characteristics were investigated with an intensified charge coupled device (ICCD) and optical emission spectroscopy measurement. The results for medical treatment with this device are to be discussed.

In this paper, we propose a Java accelerator named Javelin (Java enhanced language interpreter) based on a hardware translation method. To overcome performance hurdles in translation based accelerators, we assign registers in the host processor for frequently accessed pointers, entries of the stack, local variables, and intermediate values during bytecode execution. We propose an operand exchange unit (OPEXU) for maximizing compatibility and a stack management unit (SMU) with a smart exception handler for minimizing the overhead by stack exceptions. Javelin increases hardware cost less than 9,000 gates including a 256-byte SRAM and does not decrease the clock frequency of host processor. In our experiments, Javelin provides approximately 24.3 times better performance than that of the pure software VM in terms of execution time and it also reduces the memory traffic during Java processing about 81.9%. Consequently, Javelin provides an energy efficient solution for Java processing.

In this paper, we present a fast motion estimation algorithm based on bit-plane matching and its hardware implementation. The proposed algorithm performs motion estimation using 1-bit planes that are extracted from a video sequence. The proposed algorithm can be realized using only simple Boolean functions and makes a cheaper and faster implementation possible, while maintaining the accuracy of motion estimation. The proposed motion estimator has been implemented in FPGA and operates fast enough to handle real time video applications such as H.261/263 and MPEG-1/2.

The positioning of flip-flops in a sequential circuit is related to the power dissipation as well as the clock period of the circuit. We show that genetic algorithms can be used to find efficiently the optimal positioning for the power performance of CMOS digital circuits without sacrificing the clock periods. As the result of evaluating our design method, we reduce dissipation of power about 9-10% with preserving optimal clock period.