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31.
通过对一种设计思路新颖,具有污水贮存、均质、沉砂、除油等功能一体化的含油污水处理设施——“罐中罐”,在炼油污水处理场建设施工过程、使用效果的叙述,为炼油企业污水处理场提供结构简单、操作方便的一级处理设施的建设、改造技术。  相似文献   
32.
基于面向对象的北京市区城市内部用地信息提取   总被引:1,自引:0,他引:1  
选取北京市四环以内为研究区域,以资源三号卫星遥感影像为数据源,针对类型多样、特征易混淆的城市内部用地以及高分辨率遥感影像海量信息、人工提取费时费力等特点,论文基于面向对象分类方法,探讨城市内部用地自动提取方法,并对分类结果进行精度评估.结果表明:利用不同地物的光谱、形状、纹理和空间关系等特征,通过多尺度分割和隶属度函数法,构建合理的分类层次,不仅精确提取出研究区内水体、绿地、建设用地和待开发用地,更独具创新地区分了城市建设用地内部各种地物类型,包括工业生产用地、低密度和高密度生活用地以及交通用地.该方法有效地利用了资源3 号卫星影像的光谱、纹理及空间信息特征,总体精度可达到87.00%,Kappa系数达到0.853 9,取得较好的分类效果.  相似文献   
33.
伴随着会计电算化工作在我国各企、事业单位中的普遍深入,会计电算化档案的管理工作面临着新的创新与发展.通过对会计电算化档案特点进行分析,介绍了在会计电算化环境下会计档案脱离于原计算机系统的收集方法、不同的信息载体存储介质及计算机软硬件环境下管理与保存、软件系统版本的不断升级对电算化会计档案的调阅利用.  相似文献   
34.
Although mandatory disclosure programs have been studied extensively, strategic voluntary environmental disclosures by firms are not well understood. We study the motivations for and impacts of firms' strategic disclosure of greenhouse gas reductions to the US government. We first model firms' joint abatement and disclosure decisions, incorporating both economic and political incentives. We then use data from the Department of Energy's Voluntary Greenhouse Gas Registry to compare reported reductions to actual emissions. We find that participants in the program engage in highly selective reporting: in the aggregate, they increase emissions over time but report reductions. In contrast, non-participants decrease emissions over time. Participants tend to be large firms facing strong regulatory pressure; pressure from environmental groups reduces the likelihood of participation, suggesting such groups viewed the program as a form of greenwash. Participating in the 1605(b) program had no significant effect on a firm's changes in carbon intensity over time.  相似文献   
35.
To provide an overview of water utility information systems and the extent of computer use, a direct mail survey of all water utilities serving populations of 2,000 or more in the tri-state area - Ohio, Indiana, and Kentucky - was conducted. The following was determined: 1) utility profile information, e.g., public/private ownership, age, number of accounts, etc.; 2) an assessment of the degree of computerization presently in place to perform various functions; and 3) an assessment of any plans that the utilities may have for future computerization. To analyze the data, an index of computerization was defined as the number of departments or major activity areas of each utility that presently have some computerization. The relationship between the degree of computerization (measured by this index) and a utility's profile in terms of population served, annual revenue generated, and the number of customer accounts is discussed for each state in the survey. Discriminant analysis revealed strong significant differences between utilities that plan to use computers and those that do not. The differences were identified by the authors. Survey results revealed a rather limited use of computers in the tri-state area. Enormous potential exists in small and medium sized utilities for computerization to improve operational efficiency.  相似文献   
36.
ABSTRACT: In addition to offsetting water supply shortages, water conservation is recognized as serving many purposes, ranging from reduced energy consumption to lower capital costs. Since the discussion of these benefits has been a recent development and has generally excluded local water supply managers, a question arises as to whether supply managers are implementing conservation programs to exploit these benefits. A survey of the managers at 35 Maryland water utilities provides insight into the prevailing attitude toward conservation in a water rich eastern state. The results indicate that most managers continue to view conservation only as a short term response to temporary supply shortages. Only 12 Maryland utilities have undertaken any form of water conservation activity and just two systems have ongoing, comprehensive conservation programs. Institutional, perceptual, economic, political, and time constraints all contribute to the managers’attitudes and general inaction. If water conservation is to be widely practiced, these issues must be addressed and the benefits attributed to conservation must be better documented and articulated to supply managers.  相似文献   
37.
长江三角洲区域旅游合作初探   总被引:40,自引:0,他引:40  
长江三角洲发展旅游业有着较为成熟的现实基础。在新契机下,顺利进入以区域合作为核心的整合与发展的新阶段,必须采取合理的应对方法与正确的策略。文章运用SWOT分析方法,从宏观上对长江三角洲地区发展旅游业所具有的优势和机遇、面临的劣势和威胁的正反两方面进行了分析与阐述,提出了区域旅游合作的框架构想与对策。  相似文献   
38.
Summary Since IARC classified ELF magnetic field as Possibly Carcinogenic to Human the fear from 50/60 Hz magnetic field exposure had been increased to the state of public “panic”. Subsequently, environment quality preservation organizations increased their pressure on their government to adopt the “precautionary principle” and to reduce the allowable ELF Magnetic Field exposure to much lower values than are recommended by ICNIRP-1998. As an example the present Environmental Ministry in Israel recommendation is to lower the ELF Field exposure to 10 mG averaged over 24 h. As a result of this stringent exposure guideline imposed by the government, electrical engineers who are involved in the deployment and installation of large and medium electrical utilities, such as overhead power lines, transformers, UPS systems, electrical public transportation, switching stations, etc., are much more aware to the need to employ special measures and methods for reducing the magnetic fields that might be emitted from such utilities. There are few computer codes that are capable of analyzing with great accuracy magnetic and electric fields surrounding single phase and three phase electrical utilities in a 3-D system. The best presentations of the analysis results are by equi-value contours depicting electric and magnetic fields. This graphical presentation is a powerful design tool that enables better deployment and installation design aided to reduce the magnetic field emissions from high-power electrical utilities. This paper describes the various types of graphical presentations available for ELF field contours, the dependent and independent variants and parameters, magnetic field animation for optimization of power line installation and routing, and finally an example that demonstrates the usefulness of the graphical presentation tools.  相似文献   
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