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51.
Blom L  Hauch A 《Applied ergonomics》1982,13(4):289-292
Recently, physiotherapy students in Denmark have been spending part of their hospital training period in a factory environment, studying working postures and work methods. It is concluded that physiotherapists so trained can provide patients with a better service and treatment through their improved knowledge of the causes of illness.  相似文献   
52.
聚合物熔体挤出流动中的弹性行为   总被引:1,自引:1,他引:1  
研究了聚合物熔体挤出过程中出口压力降ΔPexit与剪切应力τw和挤出胀大比B三者之间的关系。提出了描述这一关系的方程:ΔPexit=τw(B^4-1)^05/3。初步验证,用该方程计算的ΔPexit值与文献提供的毛细管挤出实测值有较好的一致性。  相似文献   
53.
全电动注塑机的特点及应用领域   总被引:2,自引:1,他引:2  
重点分析了全电动注塑机与全液压注塑机的不同之处,简单地概述了国内塑料工业发展落后的现状以及把我国建成注塑机生产强国的突破口。详细介绍了全电动注塑机的应用领域,并展望了全电动注塑机的发展。  相似文献   
54.
介绍了N330—17.75/540/540型中间再热式大功率汽轮机机组中压缸启动的优点和方法及注意事项。对于调峰机组。旁路容量条件、控制条件具备时。建议采用中压缸启动。  相似文献   
55.
The executive attention theory of working memory capacity (WMC) proposes that measures of WMC broadly predict higher order cognitive abilities because they tap important and general attention capabilities (R. W. Engle & M. J. Kane, 2004). Previous research demonstrated WMC-related differences in attention tasks that required restraint of habitual responses or constraint of conscious focus. To further specify the executive attention construct, the present experiments sought boundary conditions of the WMC-attention relation. Three experiments correlated individual differences in WMC, as measured by complex span tasks, and executive control of visual search. In feature-absence search, conjunction search, and spatial configuration search, WMC was unrelated to search slopes, although they were large and reliably measured. Even in a search task designed to require the volitional movement of attention (J. M. Wolfe, G. A. Alvarez, & T. S. Horowitz, 2000), WMC was irrelevant to performance. Thus, WMC is not associated with all demanding or controlled attention processes, which poses problems for some general theories of WMC. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
56.
No.4326 super-wide panel of Wangzhuang Coal Mine ( in which the fully-mechanized top-coal caving longwall mining method was used) was monitored for dynamic characteristic of surface movement. The dynamic surface movement in and after mining was predicted by using the Mining Subsidence Prediction System. The results indicate that after mining, the surface above the super-wide panel reaches a state of full subsidence, making the No.309 national highway above the panel be located on the flat bottom of the subsidence basin so that the influence of mining activity in both sides of 4326 panel on the national highway is the smallest.  相似文献   
57.
简述了KDON 170 /35 0型全低压流程空分设备的操作原理、操作方法和操作依据 ,并探讨了实行间断制氧的可行性  相似文献   
58.
Demographic data show that major changes have been occurring in the everyday lives of families over the last generation, with the majority of mothers of young children in the workforce and an increasing number of men and women assuming caregiving responsibilities for older relatives. Thus, the 2 primary identities of most adults, defined by their multiple family and work roles, need to be coordinated in ways that promote positive family outcomes, returns on investments for employers, and societal values. Despite changes in the workforce, the world of work is still largely organized for a family model that is increasingly rare--one with a stay-at-home caregiver. Recommendations based on psychological and other social science research are offered to align the needs of working families and employers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
The authors used rats to study the impact of a history of opiate exposures on behavioral and autonomic responses to restraint stress. Brief restraint (30 min) provoked tachycardia and a pressor response, anxiety (as indexed by social interaction), grooming, and reduced exploration. The pressor response was reduced at 1 day, but not 7 days, after last opiate exposure; tachycardia was unaffected (Experiment 1). Stress-induced anxiety was potentiated 1 and 7 days after last opiate exposure (Experiment 2), and this potentiation was a function of dose (Experiment 3) and duration (Experiment 4) of opiate exposure. The results show that a history of opiate exposures alters vulnerability to stress and has implications for understanding coping, anxiety, and emotionality in former opiate users. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
60.
The ability to remember visual stimuli over a short delay period is limited by the small capacity of visual working memory (VWM). Here the authors investigate the role of learning in enhancing VWM. Participants saw 2 spatial arrays separated by a 1-s interval. The 2 arrays were identical except for 1 location. Participants had to detect the difference. Unknown to the participants, some spatial arrays would repeat once every dozen trials or so for up to 32 repetitions. Spatial VWM performance increased significantly when the same location changed across display repetitions, but not at all when different locations changed from one display repetition to another. The authors suggest that a major role of learning in VWM is to mediate which information gets retained, rather than to directly increase VWM capacity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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