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101.
Abstract: Protected areas cover over 12% of the terrestrial surface of Earth, and yet many fail to protect species and ecological processes as originally envisioned. Results of recent studies suggest that a critical reason for this failure is an increasing contrast between the protected lands and the surrounding matrix of often highly altered land cover. We measured the isolation of 114 protected areas distributed worldwide by comparing vegetation‐cover heterogeneity inside protected areas with heterogeneity outside the protected areas. We quantified heterogeneity as the contagion of greenness on the basis of NDVI (normalized difference vegetation index) values, for which a higher value of contagion indicates less heterogeneous land cover. We then measured isolation as the difference between mean contagion inside the protected area and mean contagion in 3 buffer areas of increasing distance from the protected‐area border. The isolation of protected areas was significantly positive in 110 of the 114 areas, indicating that vegetation cover was consistently more heterogeneous 10–20 km outside protected areas than inside their borders. Unlike previous researchers, we found that protected areas in which low levels of human activity are allowed were more isolated than areas in which high levels are allowed. Our method is a novel way to assess the isolation of protected areas in different environmental contexts and regions.  相似文献   
102.
《组织行为杂志》2017,38(5):671-691
Drawing on gestalt characteristics theory, we advance the literature on the effect of job complexity on employee well‐being by considering intra‐individual variability of job complexity over time. Specifically, we examine how the trend, or trajectory, of job complexity over time can explain unique variance of employee job strain. Across two longitudinal data sets, we consistently find that, with the average level of job complexity during a given period held constant, a positive job complexity trajectory (i.e., an increasing trend in complexity) is associated with higher employee job strain. Based on job‐demand‐control theory and the exposure‐reactivity model, we further establish that job autonomy and employee emotional stability jointly moderate the relationship between job complexity trajectory and employee job strain. Specifically, for employees with high emotional stability, job autonomy mitigates the job strain brought by positive job complexity trajectory, whereas for employees with low emotional stability, job autonomy does not help to reduce the adverse effect of the increasing trend. These findings not only contribute to extend the understanding of the job complexity – strain relationship, but also suggest a promising, dynamic avenue to study the effects of work characteristics on employee well‐being as well as other outcomes. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
103.
Excel在水环境监测数据分析中的应用   总被引:1,自引:1,他引:1  
针对水环境监测数据分析中常用的制图、水质类别判断、综合污染指数计算和湖库富营养化指数计算等方面,用VBA语言编写了在Excel中运行的宏,以提高环境监测数据处理时自动化水平,提高工作效率。  相似文献   
104.
简要介绍了活性污泥模型从传统静态模型到最新动态模型的发展过程,总结了各种活性污泥模型及其工艺软件特点,重点对国内研究进展进行了综述。  相似文献   
105.
This paper briefly presents the current practice for carrying out life cycle inventories, and mentions some advantages and drawbacks of a few dedicated software tools that are commercially available. A list is presented of some features that we think should be present in an ‘ideal’ life cycle analysis (LCA) software tool, after the specifications made at Ecobilan for the development of a specific tool for LCA. Some consideration is given to the technical difficulties involved, and the benefits that could be expected from the implementation of such features.  相似文献   
106.
化学事故应急救援指挥软件系统的设计   总被引:5,自引:0,他引:5  
从化学事故应急救援工作的实际需求出发,对化学事故应急救援指挥软件系统的设计进行了研究,分析了化学事故应急救援指挥软件系统的用户需求,提出了软件系统的设计思想和主要功能模块。  相似文献   
107.
108.
提出了采用“防火审核表”进行建筑设计防火审核的方法,设计了防火审计表,并以石油化工企业设计防火审计为例,研制了应用软件,可供有关部门参考应用。  相似文献   
109.
本文为基于GIS的公共安全应急体系中各灾害模拟和后果分析模块,研究并建立了一个从概念到实现的统一可扩展的接口,使公共安全灾害模拟和后果分析领域的研究成果能被广泛共享,并且更容易建立一个整合各类已有研究成果的软件体系.并且,本文结合"国家十五重点科技攻关(滚动)项目:合肥市公共安全应急示范试点研究"项目给出了原型实现.  相似文献   
110.
火灾中人群疏散延迟时间的研究   总被引:1,自引:0,他引:1  
田玉敏 《灾害学》2007,22(4):95-99
火灾中人员的疏散时间主要包括疏散前的延迟时间和在通道上的疏散时间。对疏散延迟时间的分布及其对疏散时间的影响进行了研究,利用Building Exodus软件对实际工程进行了模拟,并得出了一些重要的结论。这些结论对于修正传统疏散时间的工程计算方法、制定合理的人群管理对策具有重要的指导作用。  相似文献   
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