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81.
Takayanagi I. Shirakawa M. Mitani K. Sugawara M. Iversen S. Moholt J. Nakamura J. Fossum E.R. 《Solid-State Circuits, IEEE Journal of》2005,40(11):2305-2314
The ultrahigh-definition television (UDTV) camera system requires an image sensor having four times higher resolution and two times higher frame rate than the conventional HDTV systems. Also, an image sensor with a small optical format and low power consumption is required for practical UDTV camera systems. To respond to these requirements, we have developed an 8.3-M-pixel digital-output CMOS active pixel sensor (APS) for the UDTV application. It features an optical format of 1.25inch, low power consumption of less than 600 mW at dark, while reproducing a low-noise, 60-frames/s progressive scan image. The image sensor is equipped with 1920 on-chip 10-bit analog-to-digital converters and outputs digital data stream through 16 parallel output ports. Design considerations to reproduce a low-noise, high-resolution image at high frame rate of 60 fps are described. Implementation and experimental results of the 8.3-M-pixel CMOS APS are presented. 相似文献
82.
Matsumoto K. Takayanagi I. Nakamura T. Ohta R. 《Electron Devices, IEEE Transactions on》1991,38(5):999-1004
In a previous paper, the authors (ibid., vol.38, pp.989-998, May 1991) clarified the operational mechanism of a charge modulation device (CMD) image sensor and confirmed that numerical calculations using the transistor analysis program for imagers calculating non-steady-state equations (TRINE) predicted the actual performance of a CMD imager within a 20% discrepancy. Following these results, the scaling-down of device dimensions and the inherent operational speed are estimated using TRINE in order to realize a future high-resolution CMD image sensor. The analysis shows that a device size of 5.0 μm (H)×5.2 μm (V) is attainable without degrading the performance of the 10.2 μm (H)×10.4 μm (V) CMD imager and that the operational speed of a CMD is fast enough for a high-definition TV (HDTV) application which requires a scan rate of several tens of nanoseconds 相似文献
83.
Takeshi Akasaka Wataru Ando Kaoru Kobayashi Shigeru Nagase 《Fullerenes, Nanotubes and Carbon Nanostructures》1993,1(3):339-349
C60 reacts with photochemically generated bis(2,6-diisopropylphenyl)silylene (1) to give adducts, 2-4, as the isolable products. Spectroscopic analysis and theoretical investigation strongly support the silirane structure 2a, and not the isomeric 1,6-silamethano[10]annulene 2b. 相似文献
84.
Kaoru Okaniwa 《Advanced materials (Deerfield Beach, Fla.)》1994,6(6):517-517
85.
K Kimura S Hattori Y Kabuyama Y Shizawa J Takayanagi S Nakamura S Toki Y Matsuda K Onodera Y Fukui 《Canadian Metallurgical Quarterly》1994,269(29):18961-18967
The effects of wortmannin (WT), an inhibitor of phosphatidylinositol (PI) 3-kinase, on differentiation of PC12 cells were analyzed. WT inhibited PI 3-kinase activity of PC12 cells at a concentration of 10(-7) M in vivo and in vitro. Transient inhibition of PI 3-kinase activity at the time of nerve growth factor stimulation had no effect on activation of the ras protein or neurite formation by the cells. However, continuous inhibition of PI 3-kinase blocked differentiation at the step just before neurite formation. When WT was applied to cells growing neurites, elongation of the neurites was stopped at that step. These results suggest that PI 3-kinase may be involved in neurite elongation. 相似文献
86.
Based on homogeneous nucleation theory, the temperature dependence of the nucleation frequency for crystallization is calculated for a supercooled liquid. Here the solid-liquid interfacial energy of an alloy is estimated by means of an extension of Turnbull's assumption. Equations are suggested which correlate the energy with the ionization energy and the entropy of fusion for non-metallic bonded elements. 相似文献
87.
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The paper deals with the applications of probabilistic sets in system theory, especially in system identification and the design of fuzzy logic controllers. Fuzzy systems described by means of fuzzy relational equations and Λ-fuzzy systems are discussed. The identification procedure is based on some ideas of clustering techniques and probabilistic sets. Numerical examples using fuzzy and nonfuzzy data are used to illustrate the theory. 相似文献
90.
To ascertain if children assess experiences in terms of stress and if their perceptions generally agree with those of adults, fourth, fifth, and sixth graders rated 20 life events on a 7-point scale. The scale values ranged from 1.27 for the least upsetting event (the arrival of a new sibling) to 6.90 for the most upsetting event (the loss of a parent). Overall, there were no statistically significant differences associated with grade, sex, or personal experience. Children were found to make distinguishing judgments of the perceived Stressfulness that often differed from those of professionals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献