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排序方式: 共有413条查询结果,搜索用时 15 毫秒
41.
Doug Schaefer 《电子与电脑》2008,(12)
Eclipse Foundation行销总监lan Skerrett在MotorAuthority,com表示,BMW正在探寻市场,看看主流制造商是否有兴趣为车用娱乐信息系统开发一个开放来源堆栈. 相似文献
42.
Bourhan Tashtoush Mahmood Tahat Ahmed Al-Hayajneh Victor A. Mazur Doug Probert 《Applied Energy》2001,70(4):980
The performance of an open absorption-system, energized by low-grade heat such as insolation and/or waste heat, has been investigated. This combined evaporative cooler (CEC) [i.e. an indirect evaporative cooler (IEC) together with a direct evaporative-cooler (DEC)] was used to cool the air. A computer simulation of the cooling cycle was devised, so that the performance characteristics of the system could be predicted for a range of operating conditions: the influences of various design-parameters on the coefficient of performance (COP) were also evaluated. The COP of the CEC system was at least 20% greater than those achieved when employing either the IEC or DEC systems alone. 相似文献
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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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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
48.
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
49.
Doug Pulley 《电子设计应用》2005,(4):14-14,18,20,22,24,26
3G技术对于移动通信产业的变革是至关重要的,它正迅速改变着无线通信的面貌。同时,它也使得移动通信产业面临重大的技术、资金和商业运营等方面的挑战。只有通过降低通话费用,同时显著提高数据通信的效率,移动通信产业才能够顺利完成这一转变。 相似文献
50.
Proactive interference (PI) has long been recognized as a major cause of forgetting. Two experiments were conducted that offer another look at the subject by providing a detailed analysis of recall latency distributions during the buildup of and release from PI. These functions were accurately characterized by the convolution of the normal and exponential distributions (viz., the ex-Gaussian), which previously has been shown to describe recognition latency distributions. Further, the fits revealed that the increase in recall latency associated with the buildup of PI results from a slowing of the exponential retrieval stage only. The same result was found even when a short retention interval was used (and recall probability remained constant). These findings suggest that free-recall latency may be a sensitive index of the increased search set size that has often been assumed to accompany the buildup of PI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献