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91.
小城镇基础设施防灾减灾决策支持系统的研究与开发   总被引:15,自引:5,他引:15  
利用信息技术研究灾害问题成为研究热点之一 ,但在小城镇防灾减灾方面仍缺少应有的关注和重视。笔者将地理信息系统 (GIS)和决策支持系统 (DSS)集成应用于开发“基于GIS的小城镇基础设施防灾减灾决策支持系统” ,简要介绍了该系统研制目标和原则、系统结构框架及各子系统的功能 ,解决了系统实现过程中的一系列关键技术 :快速、高效构建小城镇基础空间数据库及三维可视化、应急预案及历史灾情库的电子化及各类灾害分析模拟的专业模型等。实践证明 ,基于基础设施、灾害源、防护保卫目标、应急救援力量的可视化与数字化 ,该系统能够实现对其进行科学管理、对各单一灾种的模拟分析以及应急决策支持 ,有效提高小城镇政府的应急指挥决策水平 ,增强其灾害应急反应能力。  相似文献   
92.
随着近几年中小城市发展进程的加快,城市中日益暴露出各方面的问题与弊端,污水治理问题显得尤为突出和严重。污水排放大量增加对我国中小城市水环境造成了严重的污染和破坏,因此对污水处理技术的选择与考量十分迫切。基于我国国情,我国是发展中国家,财力有限。因此用于基础设施上的资金在大城市和中小城镇之间的分配比重严重失衡,中小城镇污水的处理率相对较低。这就决定了中小城镇在选择污水处理技术时,首先要考虑的因素必须是经济、高效、节能和简便易行。  相似文献   
93.
结合小城镇环境生态区域广、生态类型多样且生态敏感度高等特点,采用DPSIR模式选取指标,建立了小城镇工业园区环境影响评价指标体系,在与城市工业园区比较、园区周围存在的农村生态系统方面提出增加资源能源利用、控制污染物排放的建议。  相似文献   
94.
This short note discusses methodological obstacles to the collection of microeconomic data in artisanal and small-scale mining communities. International donor organizations are supporting policy efforts that enhance the contribution to poverty alleviation of this mining subsector. The design and evaluation of such policy interventions require data on income, expenditure, investment, and savings in mining households and communities. These data are difficult to come by. Incomes are variable; migrants may work far from home; miners often work informally and sometimes illegally; mining populations and communities are heterogeneous and transient; and miners have many reasons to distort information. Legalization and organization of miners in cooperatives would facilitate documentation and research. These processes, however, are beyond the control of the typical policy consultant or donor organization. On their part, these parties can adopt an alternative model of research. This model involves the community in project development, data collection, and monitoring. It emphasizes continuity, cultural diversity, trust building and learning. The data thus collected should provide a firm basis for programmes that promote more sustainable livelihoods in artisanal and small-scale mining communities.  相似文献   
95.
我国小企业安全生产现状与对策   总被引:14,自引:7,他引:7  
安全生产关系人民群众的生命财产安全 ,关系改革发展和社会稳定大局。但是 ,目前我国的安全生产形势依然严峻 ,特别是改革开放以来 ,随着各种经济成分 ,尤其是三资企业、私营企业、乡镇企业和个体经济组织大量产生 ,小企业的安全生产普遍存在无人管和不会管的问题 ,重特大事故频频发生。根据国家安全生产监督管理局统计显示 ,近年来发生的特大事故中 ,70 %以上集中在小企业。笔者就中国小企业的界定标准、安全生产状况、事故频发的原因、采取的对策及取得的成绩作一简要介绍。  相似文献   
96.
基于GIS的小城镇洪灾淹没分析与应急决策系统   总被引:3,自引:0,他引:3  
近年来,将GIS技术与水文模型相结合,再根据数字高程模型DEM预测、模拟显示洪水淹没区,并进行灾害评估,已成为GIS应用和水利领域一个研究热点。笔者介绍了利用GIS技术建立的小城镇洪灾淹没分析与应急决策系统的构架、数据库的建设及其实现的功能等内容。该系统解决了一系列关键技术:小城镇空间数据库的建库技术及三维可视化、洪水淹没范围的确定以及洪水淹没实时动态演示等,能够对洪水灾害及其损失进行分析预测,对洪水灾情进行快速评估,是小城镇政府部门科学地制定防洪和减灾对策,迅速有效地采取抗洪救灾措施的保障手段。该系统适合我国现有国情,有利于维护小城镇社会经济持续稳定发展,具有很强的现实意义。  相似文献   
97.
根据当前城镇化进程中存在的主要环境问题,提出了生态环境保护与可持续发展对策。  相似文献   
98.
On the evolutionary stability of female infanticide   总被引:3,自引:0,他引:3  
Territoriality among female rodents may have evolved as an adaptation to intraspecific competition for resources or, alternatively, to defend pups against infanticide. In order to evaluate the latter, we analyse the conditions that allow an infanticidal strategy to invade a population of non-infanticidal females, and the circumstances under which infanticide may become an evolutionarily stable strategy (ESS). Our game theoretical analyses indicate that infanticide has to be associated with some direct (cannibalism) or indirect (reduced competition) resource benefits in order to invade a non-infanticidal population. We also expect that females will primarily kill litters of nearby neighbors, thereby removing the closest competitors while keeping costs at a low level. However, once established in a population, infanticide may be an ESS, even if females do not gain any resource benefits. This is theoretically possible if a female through infanticide can reduce the possibility that other, potentially infanticidal, females establish and/or stay close to her nest. While behavioral data indicate that these special circumstances sometimes occur, they may be too specific to apply generally to small rodents. Therefore, we expect that the evolutionary stability of infanticide often requires resource benefits, and that female infanticide in small rodents may, in fact, be a consequence rather than a cause of territoriality. Received: 27 June 1996 / Accepted after revision: 28 December 1996  相似文献   
99.
The paper is concerned with the impact of small business advice agencies on their clients. The work of two agencies (an Enterprise Agency and a local authority Development Unit) operating in the same geographical area (Swale in Kent) is evaluated using a survey of clients as evidence. It is concluded that both agencies are meeting real and distinctive needs among start‐up and established small businesses in the area, and have established effective systems for the delivery of their services. Quality of staff is confirmed as a key factor influencing client satisfaction with the agencies. The impact of the agencies on busines efficiency is ambiguous; it is suggested that major beneficiaries of the work of the agencies are the banks.  相似文献   
100.
Providing wastewater treatment services for small communities can be expensive, so many communities have chosen part-time or inadequately trained operators. This can result in neglect and poor plant performance. Indiana County, Pennsylvania, in the USA, has established an authority to provide operation and maintenance through a circuit riding arrangement. Two operators travel to eight plants five days a week. This has resulted in more consistent operation and maintenance at affordable rates. Homeowners pay $12.60–$18.00 and commercial customers pay $25–$150 a month. Even with regular attention, these small plants are not able to meet their effluent requirements at all times.  相似文献   
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