We have developed a car driver monitoring system for measuring drivers' consciousness, with which we aim to reduce car accidents caused by drowsiness of drivers. The system consists of the following three subsystems: an image capturing system with a pulsed infrared CCD camera, a system for detecting blinking waveform by the images using a neural network with which we can extract images of face and eye areas, and a system for measuring drivers' consciousness analyzing the waveform with a fuzzy inference technique and others. The third subsystem extracts three factors from the waveform first, and analyzed them with a statistical method, while our previous system used only one factor. Our experiments showed that the three-factor method we used this time was more effective to measure drivers' consciousness than the one-factor method we described in the previous paper. Moreover, the method is more suitable for fitting parameters of the system to each individual driver.

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A major approach for fingerprint recognition today is to extract minutiae from fingerprint images and to perform fingerprint matching based on the number of corresponding minutiae pairings. One of the most difficult problems in minutiae-based fingerprint recognition has been that the recognition performance is significantly influenced by fingertip surface condition, which may vary depending on environmental or personal causes. Addressing this problem, we have proposed an efficient fingerprint recognition algorithm using phase-based image matching. The use of phase components in 2D discrete Fourier transforms of fingerprint images makes possible to achieve highly robust fingerprint recognition for low-quality fingerprints. However, due to its high computational complexity, the proposed algorithm is not suitable to be implemented in compact fingerprint matching devices for home applications. In this paper, we propose an improved fingerprint recognition algorithm using phase-based image matching, which significantly reduces computational complexity without degrading recognition performance, compared with the reported algorithm. We also present prototype implementation of a high-performance, easy-to-use fingerprint matching device for home applications, which employ a specially designed ASIC for executing the proposed algorithm in real time.

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In this paper, we designed and fabricated a new Integrated Spatial Filtering Detector with Variable Multi-valued Weighting Function (ISFD-VMWF). This chip based on 32x32 array of n-well/p-sub photodiodes has been successfully developed using the analog/digital mixed implementation. The weighted-sum structure is proposed to realize the ISFD-VMWF. As the weighted structure, the 7-bit signed analog weighting circuit is used with cascode current mirrors. The weighting control partis consisted of digital registers in a weighted pixel element as the sum structure. The weights are controlled and programmed by external interface on the PC. Achieving the sum structure, the weighted current from each processing cell element is summed into one current signal, and two output signals, plus and minus, are outputted. These signals are converted to the voltage signal and amplified by the external differential op-amp with various gains with parallel. The experimental results show that output signals summed up are linearly shifted with changing weights as the basic characteristics of the ISFD-VMWF. To evaluate the ISFD-VMWF, another experiment of the velocity measurement was executed, which shows the effectiveness of the ISFD-VMWF on the measurement system.

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A small proton exchange membrane fuel cell (PEMFC) system with a multi-layered microreactor, which was newly developed to provide H₂ for PEMFC, was prototyped as a power source for mobile electric applications. The microreactor was designed using the simulation of chemical reaction and thermal transfer to obtain the sufficient H₂ production rate and a suitable temperature distribution for methanol reforming under the assumption of the microreactor was operated in a vacuum package to improve the system efficiency. The microreactor has four units: a methanol reformer with a catalytic combustor, a CO remover, and two vaporizers, and it was constructed of thirteen glass substrates. The small PEMFC has two humidifiers, which were composed of a hollow fiber module and a water holder. This system generated an output of approximately 2.5W at 200mA/cm² with sufficiently low heat loss. The sizes of the microreactor and the small PEMFC make this system suitable to apply as a power source for mobile devices.

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In this study, analysis of an electric field sensor using an electro optical effect by distortion of a helical structure of a ferroelectric liquid crystal was carried out. When a sine wave electric field of commercial frequency (60 Hz) was applied to a ferroelectric liquid crystal and a transmitted light intensity in a crossed nicols optical system was measured, the amplitude of the transmitted light was proportional to the amplitude of the applied electric field. In order to pursue a molecular arrangement in the helical structure, a free energy of liquid crystal was evaluated and the electro optical effect was simulated by the pursued molecular arrangement. As a result, the linear property of the electro optical effect was explained with the molecular distortion.

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A compact switch/relay with excellent high frequency performance at around 2GHz is developed by adopting a novel non-linear spring structure and high frequency signal line structure.
The non-linear spring system applied to an electrostatic actuator of RF MEMS switch/relay increases restoration force for switching reliability. The maximum restoration force can be three times higher than that of a linear spring system actuator. No failure due to restoration force shortage is observed during switching test up to 100 million cycles. The present RF MEMS switch/relay has been shown competitive RF performance over conventional RF switches such as PIN diodes and GaAs MMIC both by the experimental results.

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