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751.
SeasonalregionalizationofagriculturalhaildamageinChinaMethodandschemeofregionalization The fromtoptobottom"regionalizationmethodfacilitatestheunderstandingofmacro scopicpattern,and frombottomtotop"combinationmethodcanensuretheaccuracyofdivid inglineofregionalizationunit.Thesetwomethodsarethemostuniversalinnaturalregionalplanning,andinthispaperbothmethodsareadoptedinregionalization. First,weanalyzethespatialdistributionof 4typesofhaildamageanddefinethecombi nationofdifferentseasonaltypesacco…  相似文献   
752.
    
This article explores the issue of measuring daily ozone exposure for epidemiological studies of pollutants and their effects on health. Generally, hourly monitored ozone has been reduced to daily summary measures, which are then assumed to represent daily individual exposure to the pollutant. We instead propose the use of a functional measure of ozone exposure, which means, all hourly ozone measurements from a single day, to model short‐term health effects. Functional data analysis techniques are used to convert hourly monitored ozone from a single day into a function accounting for the daily profile of ozone. The role of this functional exposure measure is to better represent daily individual exposure and to identify the periods of daily ozone exposure that are most harmful to health. This is demonstrated by analyzing the relationship between daily hospital admissions and ozone exposure in the Italian city of Milan using functional regression models. A statistically significant association between hospital admissions and this functional measure of ozone exposure was found in the afternoon hours of the day. We propose that the functional measure of ozone exposure has superior predictive performance compared with that obtained by measuring daily exposure through summary measures. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
753.
    
round water drought events were derived by taking a truncation level through the time series of daily ground water depth that are recorded elevation differences between the water table and land surface at a well site. Droughts of various truncation levels at 70, 80, 90, and 95 percent, were obtained, where a 70 percent truncation level means that 70 percent of ground water depth data are less than or equal to the truncated value. The conditional probability that a drought occurring at a certain truncation level will prolong and advance to that of the next higher level was estimated. The regionalization analysis was conducted assuming that conditional probabilities estimated at selected wells are regionalized variables. Contour lines of conditional probabilities for each truncation level were constructed to express their spatial variability in the region. Estimation errors associated with the regionalization were reasonably small.  相似文献   
754.
实施“一控双达标”必须加强环境监测站建设   总被引:1,自引:0,他引:1  
实施“一控双达标”是本世纪末全国环境保护工作的重点。文章论述了环境监测在“一控双达标”工作中的地位、作用、目前不适应工作的几个方面以及如何加强其自身建设的对策与建议  相似文献   
755.
通过对影响我国经济—人口协调的主要因素进行分析,找出在人口系统福利与经济系统福利方面的冲突环节和发展障碍,从市场体制、人口管理体制、财税体制、领导干部政绩评价制度等方面寻找成因,提出切实可行的对策建议,为我国主体功能区经济—人口协调发展提供参考。  相似文献   
756.
This study seeks to understand to what extent and in what contexts women leaders may be advantageous for teams. More specifically, this study examines how team leader gender relates to team cohesion, cooperative learning, and participative communication. Furthermore, the study argues that advantages derived from female leadership may be contingent on teams' coordination requirements. I propose that as teams' coordination requirements increase (i.e., with functional diversity, size, and geographic dispersion), teams with women leaders report more cohesion and more cooperative and participative interaction norms than those with men leaders. I aggregated survey responses from the members of 82 teams in 29 organizations at the team level. Findings from hierarchical linear modeling analyses suggest that female leadership is more positively associated with cohesion on larger and more functionally diverse teams and more positively associated with cooperative learning and participative communication on larger and geographically dispersed teams. These results call for more research on boundary conditions on the relationship between leader gender and team outcomes, on the role of relational leadership on complex and diverse teams and, ultimately, on the potential mediating role of cohesion and team interaction norms on the relationship between leader gender and team performance. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
757.
中国药用植物的数值区划   总被引:19,自引:0,他引:19  
本文根据药用植物的地理分布,运用计算机以组平均法做聚类分析研究中药区划,将全国为4个区和8个亚区,并探讨了各区和亚区的生态环境条件,植物区系和植被特征,为中药区划和药用植物的引种栽培研究提供了一定的基础。  相似文献   
758.
以秦皇岛生态城市建设为出发点,针对秦皇岛生态城市建设中存在的生态环境问题、环境基础设施问题、产业结构问题、社会系统问题,从生态安全、生态卫生、生态产业、生态景观和生态文化五个方面进行了探讨,从而确立了秦皇岛市生态城市建设的发展战略目标,并从管理、资金、人力资源、技术等方面提出了秦皇岛生态城市建设发展的具体措施。  相似文献   
759.
Functional foods aim to provide a positive impact on health and well-being beyond their nutritive content. As such, they are likely candidates to enhance the public health official’s tool kit. Or are they? Although a very small number of functional foods (e.g., phytosterol-enriched margarine) show such promise in improving individual health that Dutch health insurance companies reimburse their costs to consumers, one must not draw premature conclusions about functional foods as a group. A large number of questions about individual products’ safety, efficacy, and affordability need to be answered before they might become an important part of the public health agenda. More importantly, though, the costs and benefits of functional foods relative to alternative mechanisms of public health improvement need to be ascertained. Alternative scenarios that warrant investigation are mainly the supply of nutraceutical ingredients in pill form targeting “at risk” groups and consumer education on diet and lifestyle.  相似文献   
760.
对新疆绿洲经济带生态功能区划进行研究,不仅可以为新疆的生态环境建设、环境治理和制定环境保护规划奠定扎实的基础,也为新疆的生态效益、经济效益和社会效益协调发展提供理论依据。以新疆沙雅县为例,根据沙雅县地理环境、生态环境特征,以《生态功能区划暂行规程》及城市生态功能区划原理为指导,在新疆省级三级生态功能区划的基础上,对沙雅县进行第四级生态功能区的划分,共划分出9个四级生态功能区,并针对每个生态功能提出了相应的生态服务功能及建设、保护发展方向。  相似文献   
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