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81.
One of the key advantages of meta‐analysis (i.e., a quantitative literature review) over a narrative literature review is that it allows for formal tests of interaction effects—namely, whether the relationship between two variables is contingent upon the value of another (moderator) variable. Interaction effects play a central role in organizational science research because they highlight boundary conditions of a theory: Conditions under which relationships change in strength and/or direction. This article describes procedures for estimating interaction effects using meta‐analysis, distills the technical literature for a general readership of organizational science researchers, and includes specific best‐practice recommendations regarding actions researchers can take before and after data collection to improve the accuracy of substantive conclusions regarding interaction effects investigated meta‐analytically. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
82.
The processes of acclimation to hot-dry and to warm-humid climates were studied using two approaches: a quantitative analysis of literature data and an experimental study in the laboratory concerning the physiological parameters of heart rate, rectal temperature, sweat loss, and subjective assessment.

Analysis o f literature data: Data from 62 experiments with a total of 813 participants were pooled and recalculated. The experiments ranged from 6 to 24 days, air temperatures from 30.4 to 50.0°C, water vapor pressures from 1.5 to 6.5 kPa, and wet bulb globe temperatures (WBGT) from 27.4 to 38.6°C.

Laboratory studies: In the laboratory, 8 participants were acclimated during 15 consecutive days to a hot-dry climate and to a warm-humid climate, which were equivalent in terms of the WBGT (33.5 and 33.6°C, respectively). The participants walked four times for 25 min on a treadmill at a speed of 4 km/h. The hot-dry climate caused somewhat greater strain than the warm-humid condition. In the course of acclimation to the hot-dry climate, heart rate and rectal temperature started at higher levels, decreased slightly steeper but remained on a higher level throughout. Nevertheless, the differences between both thermal conditions were small, and both physiologic functions reached the point of acclimation almost at the same time under warm-humid and under hot-dry exposure. Sweat loss, which is not regarded as a valid predictor for acclimation, was considerably higher but increased less in the hot-dry than in the warm-humid climate.  相似文献   
83.
84.
葛海华 《环境科技》2008,21(3):58-60
投资体制改革后项目核准备案与环评审批衔接过程中存在诸多问题,拟从政策、法律、部门配合等层面提出对策和建议。  相似文献   
85.
新疆博斯腾湖重金属污染的沉积记录   总被引:1,自引:0,他引:1  
通过测定柱芯沉积物中重金属含量,分析了新疆博斯腾湖重金属污染水平、来源及其变化趋势。结果表明,博斯腾湖西岸Pb、Zn和Cu的地质积累指数均小于0.5,污染较轻,主要来源于自然源。西南小湖区重金属Zn、Cu、Ni、Co污染较轻,主要来源于岩石风化等地球化学过程;重金属Pb和Cd污染中等,主要来源于农业活动中磷酸盐肥料的使用,1960 s以来增加显著,近年来呈明显的上升趋势。  相似文献   
86.
我国旅游灾害的研究进展   总被引:1,自引:0,他引:1  
本文首先选取了十几年来国内旅游灾害的相关文献.从文献的数量、研究区域的时空分布等角度行了分析,然后从旅游灾害的致灾要素、成因、预防旅游灾害的对策、旅游灾害预防与管理系统等方面进行综述.最后笔者提出了我国旅游灾害的研究展望.  相似文献   
87.
以往围岩位移监测的位移数据是先埋设好位移监测的设备后由工作人员定时采集。这种方式不能准确记录岩体发生变形的时间,数据量也较少,不利于对危险情况及时发现处理以及数据的后期研究分析。自动化监测系统采用短时间间隔的数据采集可以很好的克服以上的缺点。系统采用USB存储方式,将监测数据以文本文件的格式直接存储到U盘上,可以更方便的应用计算机处理数据。  相似文献   
88.
Reliability data reflects equipment safety and provides a reference for setting inspection period, thereby serving as crucial information for the implementation of equipment integrity management policies. The calculation foundation of reliability data is maintenance records of adequate data quality. However, maintenance records of doubtful quality are common. Despite excluding poor quality recodes and using only the remaining maintenance recodes to calculate the reliability data, the calculated results generally lack a sufficient degree of confidence. This study applied data mining technology, including quality metrics, the association rule, and clustering, to explore the cause of low-quality maintenance data. The results revealed that the low data quality of maintenance records was due to ineffective maintenance policies, the low integrity of key system columns, nonadherence to the policy, and misunderstanding of column definitions. The proposed method successfully identified the causes of low-quality maintenance records. By incorporating the method into the function module of a CMMS, operators can equip the system with self-diagnosis, self-supervision, and continuous optimization functions.  相似文献   
89.
The aim of this paper is to inform urban design practice through deeper understanding and analysis of the social dynamics of public outdoor space in ethnically diverse neighbourhoods. We hypothesise that findings from ethnographic research can provide a resource that improves cultural literacy and supports social justice in professional practice. The primary method is a meta-synthesis literature review of 24 ethnographic research papers, all of which explore some dimensions of public open space use and values in UK urban contexts characterised by ethnic and racial diversity. We summarise thematic understandings and significance of neighbourhood places of shared activity, parks, spaces of passing-by and of retreat. We evaluate the implications for intercultural social dynamics, exploring the spatial and temporal dimensions of conviviality and racism in public open space. We then argue that it is possible to develop principles for urban design practice informed by this work, and propose four for discussion: maximising straightforward participation, legitimising diversity of activity, designing in micro-retreats of nearby quietness and addressing structural inequalities of open space provision. We conclude that ethnographic research can provide detailed insights into the use of the public realm and also inform a more nuanced understanding of outdoor sociality relevant for an increasingly diverse society. The challenge is two-fold: for ethnographers to become less cautious in engaging with decisions and priorities regarding how cities change, and for urban designers to explicitly embed informed understandings of difference into their broad desire for inclusive public space.  相似文献   
90.
利用福建省近岸海域1959—2018年的赤潮历史记录数据资料,在地理信息系统(Geographical Information System,GIS)平台下采用核密度估计函数(kernel density estimation)对赤潮历史记录数据中的赤潮发生频次、赤潮发生持续时间、赤潮面积和赤潮藻类毒性等参数进行了空间...  相似文献   
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