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排序方式: 共有2410条查询结果,搜索用时 15 毫秒
941.
While it is generally known that interpersonal trust facilitates individual functioning, few studies have examined the role of specific features of the interpersonal trust network — individual, dyadic, third‐party, and network‐level features — on individual performance. We adopt a multilevel perspective of interpersonal trust to examine how individuals' performance is not only predicted by their individual‐level centrality in the interpersonal trust network but also moderated, at the network level, by the overall centralized nature of that network. Further, we examine whether mutual trust relationships at the dyadic level, as well as shared trust ties to common third parties, can predict individuals' performance. We test our hypotheses with 206 members in 15 professional networking groups and find that interpersonal trust operates at multiple levels to predict members' performance in terms of generating income from business referrals. These findings provide theoretical and practical implications on how interpersonal trust relationships operate and can be managed for performance gains. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
942.
Development of objective measurements is an important requirement for establishing performance-based standards for protective clothing used while handling pesticide. This study, the second in a two-part series, reports on the work completed to evaluate the performance of approximately 100 fabrics that are either used or have the potential to be used for garments worn by operators while applying pesticides. Part I, published separately, provides an overview of these issues and describes research undertaken to select a test chemical for use in subsequent studies. The goals of this study were first to develop a comprehensive approach to evaluate the performance of garments currently being used by pesticide operators, and second, to use the laboratory and field data in the development of performance specifications.  相似文献   
943.
高效内循环反应器的污泥特性   总被引:1,自引:0,他引:1       下载免费PDF全文
采用高效内循环好氧反应器处理废纸脱墨废水,结果表明,在高紊流、高剪切条件下生物活性污泥的粒径减小,使废水、生物污泥、空气充分接触,大大提高了传质速率和污泥的比好氧呼吸速率(SOUR),反应器的容积负荷和COD处理效率可分别达35kg/(m3d)和80%.  相似文献   
944.
This article presents an evaluation of the performance of the urban atmospheric dispersion model (DAUMOD) in estimating nitrogen oxides (NOx) background concentrations in Copenhagen. Estimations of hourly average (averaged over a year), mean daily and mean monthly concentrations of NOx are compared with observed values for two years of data. The model slightly underestimates low hourly average values and overestimates high values. The cumulative frequency distribution of mean daily concentration obtained from model estimations is in good agreement with the obtained from observed data. We performed a statistical analysis to determine the agreement between estimated and observed concentration values. The results show that 95.8% of hourly average estimations, 86.8% of mean daily and 100% of monthly average concentrations are within a factor of two of the observed values. The normalised mean square error of predictions is +0.13 for hourly average estimations, +0.22 for mean daily values and +0.02 for monthly mean concentrations. The fractional bias values are: –0.049 for hourly mean estimations, –0.047 for mean daily values and –0.053 for monthly average estimations. The values of the statistical parameters allow us to consider that though estimations are lightly larger than the observed values, the model performance is acceptable.  相似文献   
945.
为维护和改善湖水、水库等大型蓄水设施的水质而寻找一种新的方法,在人工的明/暗光照射条件下,探讨了运用粉末状TiO2作为光触媒,抑制各种淡水藻类增殖的效果。粉末状的TiO2,在100mg/L的浓度下,对蓝藻的铜绿微囊藻原变种、鱼腥藻和绿藻的空星藻有明显的抑制增殖的效果;而对硅藻的钝脆杆藻,在此条件下则没有效果。  相似文献   
946.
在分析职业健康安全管理体系主要要素的基础上,阐明了主要要素对持续改进的要求和组织进行持续改进的思路。  相似文献   
947.
梭鱼草净化黑臭河水的日变化试验研究   总被引:4,自引:0,他引:4  
测定了曝气和非曝气的2个植物净化槽在1 d中7个不同时间点的出水水质理化指标(pH、DO、COD、NH_4~+-N、TP)及植物叶片的叶绿素(Chla)、可溶性蛋白(SP)含量及过氧化物酶(POD)活性,另设空白槽为对照;试验目的是研究各指标的日变化情况及相互关系,为提高梭鱼草净化黑臭河水的处理效率及其植物净化槽的合理优化运行提供科学依据.结果表明,各水槽内所测指标的变化均在一定程度上与光强变化相关,对非曝气植物槽的分析发现,在出水理化指标中TP浓度与光强的相关性最好(r=0.93,p<0.01),而在植物生理指标中SP含量与光强相关性最好(r=0.91,p<0.01);植物处理使出水的DO日均值增加了0.13 mg/L,而曝气植物处理则使其增加了1.8 mg/L,曝气是对城市黑臭河水进行植物净化修复的必要辅助手段;曝气植物槽对黑臭河水中COD和NH_4~+-N的去除率日均值比植物槽升高了7.1%和6.3%(p<0.01),TP去除率却相应下降了38%(p<0.01);与非曝气槽植物相比,曝气槽植物体内Chla、SP日平均含量显著降低(p<0.05)而POD活性显著升高(p<0.05);光强和曝气的变化能迅速而显著地影响梭鱼草的生理特性从而改善其净化槽出水水质,是构建和优化黑臭河水植物净化槽时值得考虑的重要调控因素.  相似文献   
948.
The protective layer of chemical storage tank has a significant effect in risk mitigation of projectile-related accidents but the research is still in infancy. In order to investigate the performance of protective layer against projectile, dynamic response process of the large-scale vertical storage tank impacted by the end-cap fragment is simulated based on the LS-DYNA. In this paper, some key factors (thickness, layering order and number of layers) affecting its performance are discussed, which can be characterized by the deformation degrees of the target tank. It is found that the anti-penetration performance is improved rapidly with the increase of thickness, and aluminum (Al) protective layer shows a higher sensitivity to thickness change compared to Ultra-High Molecular Weight Polyethylene (UHMWPE) protective layer. Three double-layered protective layers for different sequences are investigated and the Al-UHMWPE protective layer shows best performance. For the Al protective layers arranged in various combinations of equivalent total thickness, better performance is provided by monolithic structures than layered one. This study demonstrated the rational design of the protective layer around chemical storage tanks in material selection and structure configuration.  相似文献   
949.
Activities in offshore oil and gas (OOG) that cause environmental impacts can be systematically managed through an environmental management system (EMS). Environmental performance evaluation (EPE) is an essential part of an EMS. However, previous studies on EPE indicate that existing lists of indicators little insight into how indicators are modified to more accurately assess environmental performance.In this paper, a way is proposed to identify and define specific environmental performance indicators on a case-by-case basis, which consists of five steps: (1) describing environmental requirements; (2) determining favourable outcomes corresponding to the requirements; (3) identifying required activities or issues to achieve the outcomes; (4) searching for proper measures of the activities or issues; and (5) generating a list of key indicators. Based on these steps, a quality function deployment (QFD) approach is developed to determine key indicators and evaluate environmental performance. To handle uncertainties in QFD, the decision makers’ evaluations are quantified through rough numbers using the concept of rough sets. The outputs of the proposed approach are different environmental performance indices. Using these indices, decision makers can easily determine whether an improved performance has been achieved through an EMS. The proposed approach is transparent and promising for use as a unified tool for EPE. An application of the proposed approach is demonstrated through a numerical example.  相似文献   
950.
紫外光度法臭氧分析仪性能检查与问题处理   总被引:1,自引:0,他引:1  
通过对Dasibi紫外光度法臭氧分析仪日常运行维护技术的归纳、统计和总结,整理了仪器性能检查和问题处理方法。希望对仪器的正常维护使用提供一些有益的参考。  相似文献   
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