An automated car ventilation system (automatic damper), that avoids the intake of the exhaust fume of the foregoing vehicles almost completely, was developed. The system utilizes two gas sensors to detect the exhaust fume, one for gasoline cars and the other for diesel cars. It is well known that semiconductor gas sensors show certain response delay and contaminated air may be introduced during the delay period. The present system adopts the air reservoir to store the outside air temporally to compensate the response delay. It has been demonstrated that the present system effectively discarded the contaminated air, while it introduced clean and fresh outside air. Further the data on highways suggested that the level and type of the contamination varies widely with the number and type(gasoline or diesel, freight or passenger) of running cars, traffic conditions, geographical features, and wind.

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A gas discrimination system which can estimate the concentration of the discriminated gases are proposed in this paper. TMS320C50 DSP by Texas Instruments and semiconductor gas sensor TGS823 by FIGARO Electronic are utilized for a data processing unit and a sensing probe, respectively. As for software, an artificial neural network and a fuzzy-neural network are used for the discrimination and the concentrationestimation of introduced gases, respectively. Hydrogen, vapor of alcohol and cigarette smoke are selected as domestic gas examples in the experiment, and the efficiency of the proposed system is confirmed according to the experimental results.

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BaTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ thin films were synthesized by pulsed laser deposition method using fourth harmonic generated Nd³⁺:YAG laser beam. The ferroelectric properties of BaTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ thin films were investigated by electrical measurements. Using Debye model, the frequency dependence of dielectric constant for BaTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ thin films was analyzed. The dielectric constant of multi-layerd film which was grown by Ba_xTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ (x=1.0, 3.0) targets decreased significantly with increasing frequency. On the other hand, the BaTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ thin film grown by Ba_xTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ (x=1.5) target decreased weakly with increasing frequency. The dielectric constant, remanent polarization and coercive electric field were estimated to be 118 at 1kHz, 8.7μC/cm² and 127kV/cm, respectively.
BaTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ thin film on Pt/SiO₂/Si(100) substrate showed high Curie temperature than that of BaTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ polycrystal. The RHEED intensity oscillation was observed during the deposition of SrTiO₃ buffer layer and BaTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ thin film on Nb:SrTiO₃(100) substrate. The D-E hysteresis loop of BaTi_0.91(Hf_0.5, Zr_0.5)_0.09O₃ thin film on Nb:SrTiO₃(111) substrate was observed. The remanent polarization and coercive electric field were estimated to be 3.1μC/cm² and 3.6kV/cm, respectively. Polarization fatigue measurements were carried out up to 10¹² cycles.

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A field emitter type pyroelectric infrared sensor was newly proposed. The sensor wasconstructed using field emitter tips, a MOSFET (metal-oxide-semiconductor field effect transistor) and a pyroelectric material. At first, a dependency of the emission current on the infrared incident light intensity was simulated To simulate the emission current, a measurement of the voltage responsibility on the pyroelectric material was carried out. A principle of the new sensor was confirmed by using an equivalent circuit for the infrared sensor, which is composed of discrete devices that are gated cone-shaped field emitters (n-type Si), an n-ch MOSFET and a sheet PZT. From the experiment results, it was found that the proposed device was sensitive to an infrared light of longer wavelength over 10μm and the emission current was proportional to the incident infrared light intensity. The experimental data coincided with simulated ones.

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We have found that the spatially controlled LB films with polymer backbone were fit for a sensing film of the novel gas sensor using a quartz crystal microbalance with molecular sifter function and high durability. By the systematic optimization of the film fabrication condition such as polymer concentration, number of layers and the dipping conditions of LB films, the sensor sensitivity reached 70 to 100 times of the sensor response of the conventional QCM type gas sensor. The maximum sensor response showed 7000Hz frequency shift for the small hydrophilic gas molecules such as α-pinene. The QCM type sensor using the newly developed highly organized sensing film would be promising as a high sensitivity gas sensor because of its high S/N characteristics.

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Plastic injection molding was conducted with a mold cavity mounting a precision Ni stamper, which was fabricated by the LIGA process. The used thermoplastic materials were PC (polycarbonate), TPX (polymethylpentene), and POM (polyacetal) in consideration of applications in the optical, medical, and mechatronics felds. To evaluate the high aspect ratio microstructures fabricated by plastic injection molding, the microstructures were measured as to thermoplastic material filling, mold release, flatness, and transferability. In a test pattern having lines and spaces, each material filled the bottom of a stamper having a height of 100μm and a line width of 20μm. In a test pattern including posts and gear teeth, materials filled the bottom of a stamper having 300μm in height. Measured surface roughness of both the stamper and the molded product was several tens of nm, which of a sufficient transferability for practical application using plastic injection molding.

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A rapid prototyping system using a digital micromirror device (DMD) has been developed. A DMD is a micro mechanical light modulator with tilting mirror elements. In the developed system, the DMD and a mercury lamp are used as the pattern generator and the UV source, respectively. Since the developed rapid prototyping system does not require a mask or LASER, a simple, low-cost system can be realized. An exposure pattern modulated by the DMD is projected on the saface of the UV resin, and a hardened layer with the same shape as the exposure pattern projected on the resin surface is produced. The model can be constructed in any size by changing the optical magnification. By using illuminance compensation technique, both illumination non-uniformity and excess growth are improved. The model vibration system has been introduced in order to reduce leveling time of the resin. The rapid prototyping system using the DMD is highly cost-effective.

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We produced a new vibrating gyroscope using a parallel beam structure. This gyroscope has some following sigunificant features, (1) The sensor device does not interfere to the reference vibration of the drive device. (2) This structure can convert the small Coriolis force into large concentrate strain, (3) Resonance frequency of the drive unit and the sensor unit can be easily adjusted by changing the mass of the tip. (4) Mechanical coupling can be suppressed by applied voltage to sensor device. However, this gyroscope is unsuitable for the mass-production, since the structure is complicated.
In this paper, we solve this problem by the presswork and the hydrothermal method. We optimized of the parallel beam gyroscope for the presswork based on the FEM analysis, and put PZT thin films by the hdyrothermal method. Using these two methods, we produced the dangler type gyroscope suitable for the mass production of a small size gyroscope with the advantage of the parallel beans structure.

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