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排序方式: 共有902条查询结果,搜索用时 15 毫秒
71.
Fang‐Cheng Lin Yi‐Pai Huang Ching‐Ming Wei Han‐Ping D. Shieh 《Journal of the Society for Information Display》2009,17(3):221-228
Abstract— Field‐sequential color (FSC) is a potential technique for low‐power liquid‐crystal displays (LCDs). However, it still experiences a serious visual artifact, color break‐up (CBU), which degrades image quality. Consequently, the “Stencil Field‐Sequential‐Color (Stencil‐FSC)” method, which applies local color‐backlight‐dimming technology at a 240‐Hz field rate to FSC‐LCDs, is proposed. Using the Stencil‐FSC method not only suppressed CBU efficiently but also enhanced the image contrast ratio by using low average power consumption. After backlight signal optimization, the Stencil‐FSC method was demonstrated on a 32‐in. FSC‐LCD and effectively suppressed the CBU, which resulted in more than a 27,000:1 dynamic contrast ratio and less than 40‐W average power consumption. 相似文献
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Due to pollution caused by the expansion of human activities and economic development, water quality has gradually deteriorated
in many areas of the world. Therefore, analysis of water quality becomes one of the most essential issues of modern civilization.
Integrated interdisciplinary modeling techniques, providing reliable, efficient, and accurate representation of the complex
phenomenon of water quality, have gained attention in recent years. With the ability to deal with both numeric and nominal
information, and express knowledge in a rule-based form, the Rough Set Theory (RST) has been successfully employed in many
fields. However, the application of RST has not been widely investigated in water quality analysis. The reducts generated
by RST models become very time-consuming as the size of the problem increases. Using multinomial logistics regression (MLR)
techniques to provide reducts of RST models, this investigation develops a hybrid Multinomial Logistic Regression and Rough
Set Theory (MLRRST) model to analyze relations between degrees of water pollution and environmental factors in Taiwan. Empirical
results indicate that the MLRRST model could analyze water qualities efficiently and accurately, and yield decision rules
for the staff of water quality management. Thus, the proposed model is a promising and helpful scheme in analyzing water quality. 相似文献
76.
Micromechanical modeling of hybrid composites 总被引:1,自引:0,他引:1
The main aim of this work is to study the effective elastic modulus of hybrid composites through micromechanical modeling. The micromechanical framework based on the generalized method of cells has been employed for this study. The predictions based on the present model are compared with an assortment of experimental and other theoretical predictions. The effect of two types; sequential mode and mixed mode of filler additions on the effective elastic modulus of the hybrid composite are studied. Moreover, the effect of other microstructural parameters such as the concentration, shape and aspect ratio of fillers in altering the hybridization effects are also investigated. 相似文献
77.
A hybrid method of analysis of low-speed linear induction motors 总被引:1,自引:0,他引:1
A current-excited low-speed solid-iron secondary single-sided linear induction motor (SLIM) with aluminum reaction rail is considered, A hybrid method of analysis consisting of field analysis in conjunction with the multilayer transfer-matrix concept with adjustment of secondary iron permeability to match the tangential magnetizing field in each layer is developed. It is shown that this method gives valuable information on permeability and flux penetration in secondary iron. Computed thrusts are in good agreement with test results. 相似文献
78.
风景园林实践在很大程度上受到政府决策的影响,以英国英格兰地区为例,劳动党政府于2008年提出的《儿童计划》和《游戏策略》,在为儿童游戏场地的更新和建设提供资金支持的同时,也间接推动了儿童场地设计导则与标准的发展。然而随着2010年政府换届,儿童户外游戏场地发展方案被移出了英国国家发展计划。将着重介绍在政策变化的背景下,于英格兰北部谢菲尔德市进行的名为“与自然共生”政府资助项目的实践经验,重点探究在政策引导的背景下,通过儿童户外游戏场地自然化改造的方式对社区户外空间进行适儿化提升的过程、方式和成果。将从多元参与协同工作的机制、儿童参与社区改造的方式以及儿童游戏场地的游戏价值提升等多个方面阐释该项目,为中国“十四五”规划背景下儿童友好型城市建设中社区环境优化提升面临的机遇与挑战提供基于英国经验的应对策略;对因地制宜地建设中国儿童友好城市及社区提供基于前沿实践的参考和建议。 相似文献
79.
Hyungmin Pai 《The Journal of Architecture》2015,20(6):1088-1104
80.
Cheng WL Chen YS Zhang J Lyons TJ Pai JL Chang SH 《The Science of the total environment》2007,382(2-3):191-198
Air pollution indices are commonly used to indicate the level of severity of air pollution to the public. The Pollution Standards Index (PSI) was initially established in response to a dramatic increase in the number of people suffering respiratory irritation due to the deteriorating air quality. The PSI was subsequently revised and implemented by the USEPA in 1999, and became known as the Air Quality Index (AQI) that includes data relating to particle suspension, PM2.5, and a selective options of either 8-hour or 1-hour ozone concentration during increased O3 periods. Yet, the costs of launching a network of PM2.5 monitoring stations are prohibitively high for many countries to implement the AQI from the PSI system in the foreseeable future. Therefore, the purpose of this research is to discuss the optimal method of assessing air quality using the latest developed Revised AQI (RAQI), a system that serves as an alternative to the PSI and AQI systems. The feasibility, effectiveness, and the differences between RAQI, AQI, and PSI in their applications to several air pollution conditions are also studied in this research. The results show that southern Taiwan's suspended particulates have significantly greater impact on PM2.5/PM10 ratios than in central and northern metropolitan areas, and that the ratios are higher in Taiwan as a whole compared to many other countries. We also found that the RAQI shows more significant results compared to the PSI and AQI as it has a wider coverage of the range of pollutant concentration levels. 相似文献