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961.
ABSTRACT: One of the most significant changes m the field of hydrology in the past few years has been the increase m demand for basic data resulting from a new awareness on the part of planners, developers and managers of the essential nature of such data. For many years data collection has been an onerous, routine operation, following which the data were processed and stored - either in publications or file drawers - and the job considered completed. Two developments have changed that picture: the realization that we are drastically altering OUT environment, and the advent of the computer. The first forced us into a recognition of our need for accurate basic data and the second provided a new methodology for handling and using it. The change is evidenced m many ways and numerous activities are underway at both State and Federal level for all facets of the acquisition and handling of water data. The collection of basic data still involves hard routine work and a conscientious-effort to maintain a high level of quality. Hopefully, recognition of the absolutely essential nature of an adequate data base will result in the continued enhancement of the basic data collector and the concomitant increase in support of his activities.  相似文献   
962.
Biodiesel has emerged as one of the most promising renewable energy to substitute existing petroleum-derived diesel fuel being used in transportation sectors. Among the various feedstocks reported for biodiesel production, Moringa oleifera oil is becoming a promising replacement for conventional diesel fuel. Therefore, this work provides a comprehensive overview of the recent progress in biodiesel production from Moringa oleifera oil. The physicochemical properties, fatty acid composition of oil and methyl esters, oil extraction methods, esterification, and transesterification process, and purification methods employed in the biodiesel production have been discussed.  相似文献   
963.
GIS在巨灾保险风险管理中的应用研究   总被引:2,自引:0,他引:2  
近年来 ,巨灾的不断发生 ,使得许多保险和再保险公司遭受巨大赔偿 ,乃至可能造成破产。究其原因 ,除了人们对巨灾自身难以抗拒这一客观原因外 ,保险企业对巨灾保险的风险管理方法、技术和手段的不适也是一个很重要的因素。为此 ,笔者分析了利用GIS辅助巨灾保险风险管理的优越性 ,并就GIS在巨灾保险的信息管理、风险累积预测和风险管理专家系统中所起的作用和发挥的功能分别进行了探讨。利用GIS辅助巨灾保险风险管理 ,不仅可以了解巨灾的发生和变化规律 ,进行危险性区域和费率区域的划分 ,而且可以优化保险和再保险方案 ,并通过专家系统设计出符合实用灾情的风险管理及保险管理的对策 ,对保险公司的巨灾保险风险管理起到了重要的指导作用。  相似文献   
964.
随着我国环境保护工作的深入发展,对环境管理手段提出了更高的要求,利用G1S技术实施环境管理是适应现代环境管理发展需要的。本文对环境监测监控系统作了较详细的介绍和分析,说明了环境监测监控系统在环境管理中的重要作用。  相似文献   
965.
ABSTRACT: Watershed management decision making is a complex process. Cooperation and communication among federal, state, and local stakeholders is required while balancing biophysical and socioeconomic concerns. The public is taking part in environmental decisions, and the need for technology transfer from public agencies to stakeholders is increasing. Information technology has had a profound influence on watershed management over the past decade. Advances in data acquisition through remote sensing, data utilization through geographic information systems (GIS), and data sharing through the Internet have provided watershed managers access to more information for management decisions. In the future, applications incorporating hydrologic simulation models, GIS, and decision support systems will be deployed through the Internet. In addition to challenges in making complex modeling technology available to diverse audiences, new information technology issues, such as interoperability, Internet access, and security, are introduced when GIS, simulation models, and decision support systems are integrated in an Internet environment. This paper presents a review of current use of information technology in watershed management decision making and a discussion of issues created when developing Internet based, integrated watershed management decision support systems. A prototype spatial decision support system (SDSS) for rangeland watershed management was developed using web services, which are components that communicate using text based messages, thus eliminating proprietary protocols. This new framework provides an extensible, accessible, and interoperable approach for SDSS.  相似文献   
966.
ABSTRACT: Ground water is a vital water resource in the Choushui River alluvial fan in Taiwan. A significantly increased demand for water, resulting from rapid economic development, has led to large scale ground water extraction. Overdraft of ground water has considerably lowered the ground water level, and caused seawater intrusion, land subsidence, and other environmental damage. Sound ground water management thus is essential. This study presents a decision support system (DSS) for managing ground water resources in the Choushui River alluvial fan. This DSS integrates geographic information, ground water simulation, and expert systems. The geographic information system effectively analyzes and displays the spatially varied data and interfaces with the ground water simulation system to compute the dynamic behavior of ground water flow and solute transport in the aquifer. Meanwhile, a ground water model, MODFLOW‐96, is used to determine the permissible yield in the Choushui River alluvial fan. Additionally, an expert system of DSS employs the determined aquifer permissible yield to assist local government agencies in issuing water rights permits and managing ground water resources in the Choushui River alluvial fan.  相似文献   
967.
ABSTRACT: In 2002, Wyoming became the first state to complete development of a statewide 1:24,000‐scale Watershed Boundary Dataset (WBD) under the new Federal Standards for Delineation of Hydrologic Unit Boundaries. The product was developed through the coordinated efforts of numerous state, federal, and local entities both within Wyoming and in neighboring states. Development of a comprehensive, standardized hydrologic unit boundary dataset in a “headwaters” state such as Wyoming poses a number of unique challenges. This paper details the WBD's development in Wyoming, highlighting technical methodology development and interagency coordination strategies. Evolution of the WBD standard is reviewed, addressing inconsistencies between definitions for hydro‐logic units and “true” watershed delineations. While automated methods are improving, manual and semi‐automated techniques continue to serve as valuable approaches to hydrologic unit boundary delineation given the quality of digital terrain models and the multijurisdictional nature of watershed based management. This case study provides insight on future development and maintenance of the WBD within and across other states and regions of the country and on opportunities for linking the WBD to related water resource geospatial data products like the National Hydrography Dataset.  相似文献   
968.
地理信息系统(GIS)可解决污水处理的有关信息的链接,并在地图上展示任何需要的信息,帮助人们决定在何时何地进行何种资源的配置或更新地图,实现有关信息的分享和利用,在互联网上建立本城市污水系统专用网站,使得信息的存储能力不受限制,有利于系统的维护、管理以及对问题的分析和解决。从设计原则、结构及系统的建立等方面介绍了GIS系统的设计特点。  相似文献   
969.
There is growing consensus that a combination of laissez‐faire policies, ad hoc regulation and debilitating support services has perpetuated socio‐economic and environmental deterioration in the artisanal and small‐scale mining (ASM) industry. However, a lack of anthropological and geological information on ASM prevents many governments both from improving the policy environment of the industry, and from providing more robust extension services to its operators. This article aims to examine more precisely how a deficiency of baseline census and geological data has inhibited industry formalization and undermined many of the measures implemented to address pressing problems at ASM sites. Specifically, it is argued that insufficient knowledge of artisanal mining populations — including their demographic structure — and of areas suitable for ASM activities affects the ability of a government to regularize, as well as to improve, the organization of this largely informal sector of industry. Case studies of Ghana and Zimbabwe are used to illustrate how the undertaking of low‐budget projects in areas of geological prospecting and population analysis could improve the efficiency of ASM assistance.  相似文献   
970.
Habitat restoration at a landscape scale is becoming increasingly important in environmental management. In this context, geographical information systems are well suited as they can store and integrate many of the abiotic and biotic criteria used to assess the ecological worth of a site. However, this capacity can be limited by the availability or suitability of spatial data sets. A classic example of the latter case is the National Soil Map of England and Wales, which groups soils of a varied nature into associations. Consequently the national soil map has proved to be a poor predictor of habitat suitability. Using polytomous logistic regression we put forward a method for separating soil associations into their constituent soils within the Chilterns Natural Area. This approach used soil association, aspect, slope and relative height as variables for this analysis. Whilst the model's performance is likely to have been limited by the accuracy of the soil association data set, a predictive accuracy of between 47 and 65% is sufficient to facilitate better targeting of habitat restoration when combined with other abiotic factors such as climate and topography.  相似文献   
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