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排序方式: 共有453条查询结果,搜索用时 15 毫秒
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Smart metering: The holy grail of demand-side energy management? 总被引:1,自引:0,他引:1
Doug Houseman 《Refocus》2005,6(5):23
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An experimental procedure is summarized to calculate automobile fuel consumption in the work trip and to indicate the implications of evaluating alternative subdivision street layouts. The results of the Residential Area Traffic Analysis Model show that annual fuel consumption increases with vehicle weight. The paper concludes that annual cost savings in fuel consumption and other benefits are realized by commuters who drive lighter cars. 相似文献
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The performance of Napier et al.'s typist verification algorithm (Keyboard user verification: toward an accurate, efficient, and ecologically valid algorithm, International Journal of Human-Computer Studies 43 (1995) 213-222) was assessed in a text-dependent setting. Twenty-nine subjects typed a 17 character password 50 times. False acceptance and false rejection rates were then calculated as the number of repetitions of the password included in the reference profile was increased from 6 to 20 and the number of digraphs from the password included in the verification process was increased from 2 to 16. The performance of the system (12% total error rate) was found to be comparable with the best results reported in other studies using text-dependent algorithms, and substantially better than that reported in studies using a text-independent paradigm with passwords of this length. The relationship between password length and reference profile size was found to conform to an exponential decay function, which accounted for 92% of the variability in verification error rates. 相似文献
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Chul‐Hyun Yoon Jin‐Sup Shin In‐Woo Cheong Doug‐Youn Lee Young‐Jun Park Jung‐Hyun Kim 《应用聚合物科学杂志》2003,90(3):792-798
The effect of interfacial crosslinking on miscibility behavior in blend systems of isocyanate‐functionalized poly(n‐butyl methacrylate) (PBMA) and a carboxylic alkali‐soluble resin, poly(styrene/alpha‐methylstyrene/acrylic acid) (SAA), was studied with different dimethyl meta‐isopropenyl benzyl isocyanate (TMI) concentrations. For the blend films of pure PBMA and SAA, both theoretical analysis and direct observation showed immiscibility between PBMA and SAA. For the blend systems of isocyanated PBMA and SAA, Fourier transform infrared spectra and gel permeation chromatography analyses qualitatively showed the crosslinking between the isocyanate group in isocyanated PBMA and the carboxylic group in SAA. Two tan δ peaks were shown in the blend system of SAA and isocyanated PBMA containing low concentrations of TMI (from 0 to 5 wt %), and the span of the two peaks became shorter as the TMI concentration increased. For a high TMI concentration (7 wt %), only one tan δ peaks was observed. This result means the interfacial crosslinking between isocyanated PBMA and SAA occurred fully, and thus the miscibility between two polymers was significantly improved. As these results showed, the tensile strength of the blend film of isocyanated PBMA and SAA was higher than that of pure PBMA and SAA. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 792–798, 2003 相似文献
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Passage meditation reduces perceived stress in health professionals: A randomized, controlled trial.
The authors evaluated an 8-week, 2-hr per week training for physicians, nurses, chaplains, and other health professionals using nonsectarian, spiritually based self-management tools based on passage meditation (E. Easwaran, 1978/1991). Participants were randomized to intervention (n = 27) or waiting list (n = 31). Pretest, posttest, and 8- and 19-week follow-up data were gathered on 8 measures, including perceived stress, burnout, mental health, and psychological well-being. Aggregated across examinations, beneficial treatment effects were observed on stress (p = .0013) and mental health (p = .03). Treatment effects on stress were mediated by adherence to practices (p = .05). Stress reductions remained large at 19 weeks (84% of the pretest standard deviation, p = .006). Evidence suggests this program reduces stress and may enhance mental health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献