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81.
Tatsuhiko Matsumoto Satoru Kubota Yuta Kubota Kenta Imabayashi Kazuyuki Kishimoto Seiichi Goshi Shigeki Imai Youichi Igarashi Shuichi Haga Takehiro Nakatsue 《Journal of the Society for Information Display》2011,19(11):813-820
Abstract— To understand actual viewing conditions at home is important for TV design. And the preferred luminance level of LCD TVs under actual viewing conditions is also important in order to obtain both good picture quality and low power consumption. The actual viewing conditions of households and the preferred luminance levels was investigated. In a field test of 83 households, the display luminance, screen illuminance, and viewing locations were measured on site. In laboratory experiments, young and elderly subjects adjusted the luminance of an LCD‐TV screen to their preferred levels under different screen illuminance levels, angular screen sizes, and average luminance levels (ALL) of the images. As a result, two equations, which represent the preferred luminance level of LCD‐TV screens corresponding to different viewing conditions for young and elderly subjects were obtained. When the ALL of the images was 25% and the screen illuminance and angular screen size were set at 100 lx and 20°, respectively, the preferred luminance was 1 60 cd/m2 for the young subjects and 248 cd/m2 for the elderly subjects. By using the setting of the preferred luminance of an LCD TV under actual viewing conditions, it is possible to conserve energy consumption. 相似文献
82.
83.
This paper presents an algebraic approach to polynomial spectral factorization, an important mathematical tool in signal processing and control. The approach exploits an intriguing relationship between the theory of Gröbner bases and polynomial spectral factorization which can be observed through the sum of roots, and allows us to perform polynomial spectral factorization in the presence of real parameters. It is discussed that parametric polynomial spectral factorization enables us to express quantities such as the optimal cost in terms of parameters and the sum of roots. Furthermore an optimization method over parameters is suggested that makes use of the results from parametric polynomial spectral factorization and also employs two quantifier elimination techniques. This proposed approach is demonstrated in a numerical example of a particular control problem. 相似文献
84.
We consider the minimum maximal matching problem, which is NP-hard (Yannakakis and Gavril (1980) [18]). Given an unweighted simple graph G=(V,E), the problem seeks to find a maximal matching of minimum cardinality. It was unknown whether there exists a non-trivial approximation algorithm whose approximation ratio is less than 2 for any simple graph. Recently, Z. Gotthilf et al. (2008) [5] presented a -approximation algorithm, where c is an arbitrary constant.In this paper, we present a -approximation algorithm based on an LP relaxation, where χ′(G) is the edge-coloring number of G. Our algorithm is the first non-trivial approximation algorithm whose approximation ratio is independent of |V|. Moreover, it is known that the minimum maximal matching problem is equivalent to the edge dominating set problem. Therefore, the edge dominating set problem is also -approximable. From edge-coloring theory, the approximation ratio of our algorithm is , where Δ(G) represents the maximum degree of G. In our algorithm, an LP formulation for the edge dominating set problem is used. Fujito and Nagamochi (2002) [4] showed the integrality gap of the LP formulation for bipartite graphs is at least . Moreover, χ′(G) is Δ(G) for bipartite graphs. Thus, as far as an approximation algorithm for the minimum maximal matching problem uses the LP formulation, we believe our result is the best possible. 相似文献
85.
Alexander-Kaufman K Cordwell S Harper C Matsumoto I 《Proteomics. Clinical applications》2007,1(1):62-72
Alcoholic patients commonly experience cognitive decline. It is postulated that cognitive dysfunction is caused by an alcohol-induced region-selective brain damage, particularly to the prefrontal region, and grey and white matter may be affected differently. We used a proteomics-based approach to compare protein expression profiles of the dorsolateral prefrontal cortex (Brodmann area 9 (BA9)) from human alcoholic and healthy control brains. Changes in the relative expression of 110 protein 'spots' were identified in the BA9 grey matter, of which 54 were identified as 44 different proteins. In our recent article, 60 protein spots were differentially expressed in the BA9 white matter and 18 of these were identified (Alexander-Kaufman, K., James, G., Sheedy, D., Harper, C., Matsumoto, I., Mol. Psychiatry 2006, 11, 56-65). Additional BA9 white matter proteins are identified here and discussed in conjunction to our grey matter results. Thiamine-dependent enzymes transketolase and pyruvate dehydrogenase (E1β ubunit) were among the proteins identified. To our knowledge, this is the first time a disruption in thiamine-dependent enzymes has been demonstrated in the brains of 'neurologically uncomplicated' alcoholics. By identifying protein expression changes in prefrontal grey and white matter separately, hypotheses may draw upon more mechanistic explanations as to how alcoholism causes the structural alterations associated with alcohol-related brain damage and cognitive dysfunction. 相似文献
86.
87.
In the present paper, we report results of surveys in 2003 in Japan and Denmark about patients' views about adverse events, focusing on the actions of healthcare staff involved in a medical accident. Results show that patients were more likely to indicate negative expectations to a doctor's reactions after a medical accident when asked in general terms than when asked in relation to concrete case stories. When asked in general terms, 66% (47%) of Japanese (Danish) respondents expected that doctors sometimes hold back on providing information to patients about a medical accident, while 37% (7%) did so when asked about a concrete, mild-outcome case. We examine some possible reasons for the relatively high level of distrust of Japanese patients, and we discuss whether the seemingly lower level of disclosure in Japan than in Denmark and the negative stories in the Japanese press may have an impact. We also suggest some implications for introducing a patient-centred or customer-centred approach to risk management in healthcare and other domains. 相似文献
88.
A new heat-resistant Fe-based cast alloy has been designed making the best use of the CALPHAD method. The objective was to replace the material for precision cast products made from Ni-based superalloys with improved Fe-based alloys originally developed for lower temperature applications.The key to the design is to balance the amount of strengthening - Ni3(Ti,Al) precipitates and brittle phase, and to simultaneously decrease as-cast microsegregation. Contours of the equal phase fraction were calculated over the isothermal diagrams of the Fe–Ni–Cr–Ti–Al–Nb system, and provided useful guidelines for compositional modifications. The microsegregation was also evaluated by Scheil-type simulation in order to reduce micropores caused by oxidation of the solidifying front.The developed cast Fe-based alloy showed desirable strength at the envisioned service temperatures and filled the open range of heat resistance between Ni-based superalloys and the original alloy. 相似文献
89.
Yasuhiro Kobayashi Masaaki Ohkita Michio Inoue 《Mathematics and computers in simulation》1976,18(2):115-122
For an analog simulating system, an approximating system is proposed. Its mathematical form is expressed by an algebraic equation: with four parameters given by real numbers. Their values can be determined so as to satisfy a best fit in a Chebyshev sense. Then, the accuracy is of the same order with that obtained by any kind of ordinary power series up to terms o f the third order. It is noticeable that a given function can be accurately approximated by this equation without destroying its uniform continuity.As its electronic system, it is possible to utilize forward current-voltage characteristics o f p-n diodes near their origins. Different functions can be produced by adjusting an amount o f ordinary resistances connected to diodes in series. 相似文献
90.
Koji Matsumoto Ken Oikawa Masashi Okada Yoshikazu Teraoka Tetsuo Kawagoe 《International Journal of Refrigeration》2006,29(6):1010
This study focuses on an emulsion as a new thermal storage material for ice storage. Two types of emulsions were formed using an oil–water mixture with a small amount of additive. A silicone, light and lump oils were used. The water contents of the emulsions were 70, 80 and 90%. The additive was an amino group modified silicone oil. No depression of freezing point was observed for the emulsions because of their hydrophobic properties. In order to determine the structure of the emulsions, their electrical resistances were measured. Moreover, components of the liquids separating from the emulsions were analyzed. The results indicated that one emulsion was a W/O type emulsion, while the other was an O/W type. Finally, adaptability of the two emulsions to ice storage was discussed, it was concluded that a high performance ice slurry could be formed by the W/O type emulsion. 相似文献