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191.
Introduction: Providing a sense of supervision for parents may facilitate their children’s involvement in physical outdoor activities, such as walking to school. Information technology (IT) solutions could bring more parental supervision, which in turn has the potential to enhance the proportion of walking trips to school. This study aimed to examine the role of a proposed hypothetical IT solution that gives parents real-time information about children’s entrance to and exit from the school, for the intention of parents letting their children walk to school. Method: A total of 820 questionnaires were distributed among pupils aged 7–9-years across 28 elementary schools to be completed by their parents (82% return rate). Results: Compared to the group of walking pupils, increased parental intention to let their children walk to school under the proposed solution could be explained by considerably more variables in the group of pupils who did not walk to school. The findings revealed that increased parental intention was higher among the walking pupils compared to the non-walking pupils. For the non-walking pupils, enhancement of walking facilities across the school area could potentiate the use of the proposed solution by the parents, which in turn may increase the proportion of walking on school trips. In addition, boy pupils, the pupils whose parents evaluated walking more favorable, those from lower socioeconomic backgrounds, and those living in close proximity to the school could more likely benefit by shifting from non-walking to walking modes of travel, after implementation of the solution.  相似文献   
192.
氯代苯类化合物对江水细菌的毒性及QSAR研究   总被引:12,自引:0,他引:12  
采用细菌生长抑制实验,测定了18种氯苯类化合物对长江水中混合细菌的毒性,得到24 hIC50值,-1gIC50为3.65~4.32,其中,毒性最弱的是氯苯,毒性最强的是1,2,4-三氯苯.选用分子连接性指数法对毒性数据进行定量结构活性关系(QSAR)研究.结果表明,氯苯类化合物对江水细菌的毒性与苯环上取代基的种类、数目和位置有关,价分子连接性指数0XV和7XCHV能够很好地描述氯苯类化合物对江水细菌的毒性.方程-1gIC50=0.8390XV-25.3727XCHV+0.802的稳健性很好,该模型的预测值与毒性实测值之间的相关系数达0.948.   相似文献   
193.
The study of a method of regional environmental risk assessment   总被引:2,自引:0,他引:2  
Regional environmental risk assessment can be defined as risk assessment which deals with a spatial scale that contains multiple habitats with multiple sources of many stressors affecting multiple endpoints. The characteristics of the landscape also affect the estimated risk. In this paper, an information diffusion method based on a grid system is proposed to assess regional environmental risk. The risk information on a single environmental risk source can be diffused effectively by using fuzzy set theory. Regional environmental risk values obtained from information diffusion can be clustered on classification criteria and different environmental risk levels can be depicted in a spatial partition map. Huangge Town and Nansha Town located in the Nansha Area of Guangzhou City in China were selected as model cases. The results derived from this information diffusion method will help the local government to optimize the distribution of industrial areas and establish risk prevention measurements and emergency management procedures.  相似文献   
194.
ABSTRACT

Americans’ concern about water quality has increased over the years. Indeed, several water issues made national news coverage during the past few years, such as lead in Flint, Michigan, algae blooms in Florida, and water quality at the Rio Olympics. In this study, we test two alternate paths of engagement relative to how people respond to water problems. First, we examine anxiety as a key variable that triggers active information seeking behaviors. Second, we look at hopelessness as an intervening variable that could explain why some people become disengaged with issues. Additionally, we test whether response efficacy moderates the relationships between perceiving a problem with water and these emotions. Using survey data collected during the fall of 2015, we examine the role of different emotions in increasing and decreasing active information seeking behaviors.  相似文献   
195.
为增加有效降水,降低干旱和雾霾等环境污染的影响,保护生态环境安全,研制了以提高开发空中水资源能力为主要目的、基于GIS技术的人工增雨作业决策指挥系统,依托新一代多普勒天气雷达、Micaps数据资料和自动站数据库,应用Microsoft C#语言开发了增雨作业预警和指挥功能、指挥信息和作业信息收集互传功能、增雨效果评估功能、常规业务管理功能,构建了功能较为完善的业务系统。  相似文献   
196.
上海环境信息系统是为环境管理、决策提供科学化、定量化服务的信息系统。简要介绍了它的建设规划和总体目标。上海环境信息系统由代码和标准、图形信息、环境质量、污染源、环境管理、计划支持和环境预测决策等7个控制子系统组成,实施计划分三步走。19910~1993年,基本建成环境基本信息库。1994~1997年,基本建成环境管理信息库。1998~2000年,基本建成环境决策支持系统。同时,还就环境信息系统建设  相似文献   
197.
煤矿职工教育信息管理系统的开发   总被引:2,自引:0,他引:2  
为了加强煤矿企业的安全管理 ,降低事故频率 ,提高劳动生产率 ,笔者详细介绍了用VFP软件开发的煤矿职工教育信息管理系统。实践证明该系统具有安装方便、界面友好、功能齐全等特点 ,在煤矿企业有推广应用价值。  相似文献   
198.
介绍了近年来国内外应急管理平台的建设情况,就系统建设和制度建设中容易出现的一些问题进行了探讨,并以沈阳市环境应急综合管理信息系统为例,介绍了基于突发事件应急管理框架的环境应急管理系统事前预防、事中应急和事后恢复的3个功能模块及该系统的一些特点。  相似文献   
199.
Booth, Nathaniel L., Eric J. Everman, I‐Lin Kuo, Lori Sprague, and Lorraine Murphy, 2011. A Web‐Based Decision Support System for Assessing Regional Water‐Quality Conditions and Management Actions. Journal of the American Water Resources Association (JAWRA) 47(5):1136‐1150. DOI: 10.1111/j.1752‐1688.2011.00573.x Abstract: The U.S. Geological Survey National Water Quality Assessment Program has completed a number of water‐quality prediction models for nitrogen and phosphorus for the conterminous United States as well as for regional areas of the nation. In addition to estimating water‐quality conditions at unmonitored streams, the calibrated SPAtially Referenced Regressions On Watershed attributes (SPARROW) models can be used to produce estimates of yield, flow‐weighted concentration, or load of constituents in water under various land‐use condition, change, or resource management scenarios. A web‐based decision support infrastructure has been developed to provide access to SPARROW simulation results on stream water‐quality conditions and to offer sophisticated scenario testing capabilities for research and water‐quality planning via a graphical user interface with familiar controls. The SPARROW decision support system (DSS) is delivered through a web browser over an Internet connection, making it widely accessible to the public in a format that allows users to easily display water‐quality conditions and to describe, test, and share modeled scenarios of future conditions. SPARROW models currently supported by the DSS are based on the modified digital versions of the 1:500,000‐scale River Reach File (RF1) and 1:100,000‐scale National Hydrography Dataset (medium‐resolution, NHDPlus) stream networks.  相似文献   
200.
The active management of air-filled cave systems is virtually non-existent within the karst landscape of west-central Florida. As in every karst landscape, caves are important because they contain a wide variety of resources (e.g., biota, speleothems) and can act as direct connections between surface and subsurface hydrological processes, potentially exacerbating the pollution of groundwater. Before sound management policies can be drafted, implemented, and enforced, stakeholders must first have knowledge of the management requirements of each cave. However, there is an informational disconnect between researchers, stakeholders, and the recreational caving community. Here, we present a cave inventory system that simplifies the dissemination of resource knowledge to stakeholders so that cave management and protection policies can be drafted and implemented at the state and local level. We inventoried 36 caves in west-central Florida, located on both public and private land, and analyzed cave resource data to provide insights on cave sensitivity and disturbance using two standardized indices. The data revealed that both public and private caves exhibit a wide range of sensitivity and disturbance, and before management strategies can be drafted, the ownership of each cave must be considered. Our inventory geodatabase serves as a link between researchers, landowners, and the public. To ensure the conservation and protection of caves, support from county or state government, combined with cave inventory data, is crucial in developing sound management policy.  相似文献   
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