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101.
Wavelength response of harmonic distortion in ac-bias recording is analyzed. The wavelength response is affected in both the record and playback processes. In the record process tape nonlinearity and magnetization phase shift, which is dependent on signal-field intensity, are taken into account. In the playback process, tape thickness, tape-to-head spacing, gap length, etc. axe taken into account. An approximate expression for the third-harmonic distortion is derived. The experimental data show quantitative agreement with theory. 相似文献
102.
Algorithms for Extracting Correct Critical Points and Constructing Topological Graphs from Discrete Geographical Elevation Data 总被引:12,自引:0,他引:12
Shigeo Takahashi Tetsuya Ikeda Yoshihisa Shinagawa Tosiyasu L. Kunii Minoru Ueda 《Computer Graphics Forum》1995,14(3):181-192
Researchers in the fields of computer graphics and geographical information systems (GISs) have extensively studied the methods of extracting terrain features such as peaks, pits, passes, ridges, and ravines from discrete elevation data. The existing techniques, however, do not guarantee the topological integrity of the extracted features because of their heuristic operations, which results in spurious features. Furthermore, there have been no algorithms for constructing topological graphs such as the surface network and the Reeb graph from the extracted peaks, pits, and passes. This paper presents new algorithms for extracting features and constructing the topological graphs using the features. Our algorithms enable us to extract correct terrain features; i.e., our method extracts the critical points that satisfy the Euler formula, which represents the topological invariant of smooth surfaces. This paper also provides an algorithm that converts the surface network to the Reeb graph for representing contour changes with respect to the height. The discrete elevation data used in this paper is a set of sample points on a terrain surface. Examples are presented to show that the algorithms also appeal to our visual cognition. 相似文献
103.
Kiyoshi Minoura Shigeaki Mizushima Yasushi Asaoka Ichiro Ihara Eiji Satoh Sayuri Fujiwara Yasuhisa Itoh 《Journal of the Society for Information Display》2008,16(1):129-136
Abstract— A novel reflective color LCD without polarizers has been developed using a PDLC film and a retro‐reflector. Bright color images including moving images are achievable with ambient light. This novel LCD will enable the new application area of electronic paper. 相似文献
104.
Haijun Jia Hiroshi Kuraseko Hiroyuki Fujiwara Michio Kondo 《Solar Energy Materials & Solar Cells》2009,93(6-7):812-815
For fast deposition of microcrystalline silicon (μc-Si:H) films, a microwave-induced high-density plasma source is developed. By using this plasma source, highly crystallized μc-Si:H films can be deposited from SiH4+He plasma without even using H2 dilution and substrate heating. A systematic deposition study shows that the film deposition rate increases with increase in the input microwave power and the SiH4 flow rate. The film crystallinity also improves with power but degrades with increase in the SiH4 flux. After optimizing the plasma conditions, the deposition of a highly crystallized μc-Si film has been realized at an ultrafast deposition rate higher than 700 nm/s. 相似文献
105.
Characteristic Instabilities in HfAlO Metal–Insulator–Metal Capacitors Under Constant-Voltage Stress
Takeda K. Yamada R. Imai T. Fujiwara T. Hashimoto T. Ando T. 《Electron Devices, IEEE Transactions on》2008,55(6):1359-1365
Time-dependent characteristic changes of metal-insulator-metal (MIM) capacitors with HfAlO dielectric prepared by atomic-layer deposition under constant-voltage stress (CVS) were studied. It was found that relative dielectric constant , dielectric loss , temperature coefficient of capacitance , and frequency coefficient of capacitance gradually increase during CVS testing, whereas the voltage dependence of capacitance weakens. It was also found that changes in -value, , and during CVS testing linearly depend on changes in . These three linear relationships are basically explained by a dielectric-response model proposed for a ldquoflat-lossrdquo dielectric. That is, the increases in -value, , and are attributed to the dielectric-loss increase caused by voltage stress. Stress-time dependence of the dielectric-loss increase is expressed very well by a power function. That is, the power exponent obtained by a curve fitting linearly increases with stress voltage and decreases with increasing aluminum concentration in the HfAlO dielectric. This result indicates that aluminum addition into the HfAlO dielectric can improve the characteristic stabilities of a MIM capacitor under voltage stress. 相似文献
106.
K Oka K Hayashi T Nakazato T Suzawa K Fujiwara T Saruta 《Canadian Metallurgical Quarterly》1997,36(10):700-704
A 40-year-old male, with a past history of hypertension but receiving no medical treatment, was referred. He manifested malignant hypertension (190/130 mmHg; Keith-Wagener III), renal dysfunction (serum creatinine, 3.8 mg/dl), and elevated plasma aldosterone (450 pg/ml) and active renin concentration (ARC, 104 pg/ml). His blood pressure was controlled with multiple antihypertensive agents and ARC thus decreased (4.3 pg/ml), but aldosterone remained elevated. Abdominal magnetic resonance imaging (MRI) revealed a right adrenal adenoma, and aldosterone-producing adenoma was confirmed by adrenal venous sampling. Primary aldosteronism very rarely develops to malignant hypertension, and even in that case ARC is suppressed. Therefore this is a rare case of primary aldosteronism complicated with malignant hypertension and high ARC. 相似文献
107.
Fujiwara H. Nii K. Noguchi H. Miyakoshi J. Murachi Y. Morita Y. Kawaguchi H. Yoshimoto M. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2008,16(6):620-627
We propose a low-power two-port SRAM for real-time video processing that exploits statistical similarity in images. To minimize the discharge power on a read bitline, a majority-logic circuit decides if input data should be inverted in a write cycle, so that ldquo1rdquos are in the majority. In addition, for further power reduction, write-in data are reordered into digit groups from the most significant bit group to the least significant bit group. The measurement result of a 68-kbit video memory in a 90-nm process demonstrates that a 45% power saving is achieved on the read bitline. The speed and area overheads are 4% and 7%, respectively. 相似文献
108.
Ruwan Gallage Atsushi Matsuo Takeshi Fujiwara Tomoaki Watanabe Nobuhiro Matsushita Masahiro Yoshimura 《Journal of the American Ceramic Society》2008,91(7):2083-2087
Crystalline CeO2 films and patterns have been successfully fabricated in a "single-step process" at moderate temperature. In this process, the combination of the ink-jet technique and depositing the precursor on a hot substrate (≤300°C) gave crystalline CeO2 without further heat treatment. X-ray diffraction analysis revealed that the phase formed was crystallized ceria with nanosized (<10 nm) crystallites. The film thickness was several hundred nanometers and the pattern width was about 150 μm. Scanning electron microscopy analysis showed that the films and patterns were free of cracks and adhered to the substrate. This is the first report about the direct patterning of crystalline CeO2 without postfiring or posttreatments like masking, etching, etc. 相似文献
109.
K. Fujiwara 《Wear》1978,51(1):127-136
The effect of silicon on the adhesion of noble metals has been studied using a twist-compression bonding test and an ultrahigh vacuum test. The specimen surfaces were analysed using ion microprobe mass analysis and electron spectroscopy for chemical analysis. It was found that silicon, whether introduced on the surface as an impurity or present as an alloy component, was effective in preventing adhesion in air because of the formation of silicon oxide. The oxidation rate of silicon and metal-silicon alloy systems is qualitatively discussed considering changes in adhesion coefficient and contact resistance.Twist-compression bonding tests of noble-metal alloys containing an active additive such as silicon were found to be affected by the surrounding atmosphere. 相似文献
110.
Hiroaki Yonemura Koichi Yuno Yuuichi Yamamoto Sunao Yamada Yoshihisa Fujiwara Yoshifumi Tanimoto 《Synthetic Metals》2009,159(9-10):955-960
Nanowires consisting of regioregular poly(3-hexylthiophene) (P3HT) as a conducting polymer were prepared using p-xylene. Magnetic processing of the nanowires was carried out using two superconducting magnets with horizontal (Bmax = 8 T) and vertical (Bmax = 10 T) directions. The formation of the nanowires was confirmed by atomic force microscopy (AFM) measurement. The results from the AFM images and the polarized absorption spectra on glass plates indicated that the nanowires partly oriented themselves with their long axes, which are parallel to the π–π stacking direction, being perpendicular to the magnetic field. The magnetic orientation is most likely ascribed to anisotropy in the magnetic susceptibilities of the ordered P3HT in the nanowires. 相似文献