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排序方式: 共有408条查询结果,搜索用时 15 毫秒
51.
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
52.
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
53.
This paper presents a methodology to identify robust operating regions through the selection of controllable factory variables, using discrete event simulation. A casting plant melt facility was used as an industrial test bed to develop these techniques. A robust system design was determined by response surface analysis of key production parameters. Furthermore, robust operating policies that maximise throughput, while minimizing work-in-progress and thus energy consumption were identified. 相似文献
54.
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
55.
Statisticians typically recommend completely randomized experimental designs. The reasoning behind this advice is theoretically sound. Unfortunately, engineers who typically run industrial experiments frequently fail to recognize restrictions on randomization, i.e., split-plot experiments, and are often unaware of the risks associated with analyzing split-plot experiments as if they were randomized. Similarly, issues concerning the inference space of the experiment frequently are not given adequate consideration. Conversely, statisticians frequently are unaware that a restriction on randomization does not necessarily translate into less information than a completely randomized design.
In this paper, we discuss a proactive methodology for identifying and incorporating information concerning restrictions on randomization and inference space in industrial experiments. We also present the factor relationship diagram (FRD), a tool that assists engineers in the recognition of restrictions of randomization and guides the development of questions that encourage the experimenter to understand those sources of variation that may contribute to a lack of precision in a split-plot experiment or lack of repeatability in inference space different from that studied in the experiment. Examples that illustrate the use of the methodology and the FRD are included. 相似文献
In this paper, we discuss a proactive methodology for identifying and incorporating information concerning restrictions on randomization and inference space in industrial experiments. We also present the factor relationship diagram (FRD), a tool that assists engineers in the recognition of restrictions of randomization and guides the development of questions that encourage the experimenter to understand those sources of variation that may contribute to a lack of precision in a split-plot experiment or lack of repeatability in inference space different from that studied in the experiment. Examples that illustrate the use of the methodology and the FRD are included. 相似文献
56.
Doug Burch Jonathan W. Martin Mark R. VanLandingham 《Journal of Coatings Technology》2002,74(924):75-86
A heat and moisture transfer model was used to study weathering of polymeric materials, such as paint, asphalt, sealants,
plastics, textiles, and polymeric composites. Three damage indices, related to temperature changes, humidity changes, and
time of wetness, respectively, were introduced to quantify adverse effects of climate. The variation of these indices was
investigated for a hot and humid climate (Miami, FL) and a hot and dry climate (Phoenix, AZ). In addition, the relative effects
of solar radiation, surface wetting by rain and dew condensation, and variations in outdoor temperature and relative humidity
on the three damage indices were investigated.
100 Bureau Dr., Stop 8621, Gaithersburg, MD 20899-8621. 相似文献
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This paper surveys machine induction techniques for database management and analysis. Our premise is that machine induction facilitates an evolution from relatively unstructured data stores to efficient and correct database implementations. 相似文献