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601.
基于技术扩散的客流量预测 总被引:2,自引:0,他引:2
旅游客流预测是旅游开发的基础研究内容.由于旅游客流具有动态的变化性和影响因素的多样性等特征,使定量的描述和预测旅游客流量具有较大的难度.鉴于此,综合技术扩散理论和区位论等理论,根据技术扩散的思想,在区域选择分析的基础上建立了具有较强实用性的客流动态预测模型. 相似文献
602.
Ryan C. Miller D. Phillip Guertin Philip Heilman 《Journal of the American Water Resources Association》2004,40(2):347-357
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
603.
Chen Wuing Liu 《Journal of the American Water Resources Association》2004,40(2):431-442
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
604.
Wendy L. Berelson Paul A. Caffrey Jeffrey D. Hamerlinck 《Journal of the American Water Resources Association》2004,40(5):1231-1246
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
605.
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
606.
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
607.
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
608.
609.
Land-use planning using geographic information systems (GIS) commonly emphasizes biophysical spatial data; however planning
can be improved by integrating spatial sets of socioeconomic data into the GIS. As an example, we compared a traditional GIS-aided
forestry planning protocol that considered only biophysical suitability, with an integrated GIS-aided approach that incorporated
both biophysical and socioeconomic suitability. The analyses were conducted for the planning of plantation investments in
the Kyaukpadaung Township in the dry zone of central Myanmar. The traditional approach used three biophysical layers for suitability:
land use, slope, and accessibility. In contrast, the integrated GIS approach included biophysical suitability data, perceptions
and preferences of local villagers towards forestry (social suitability), and quantitative socioeconomic data. The results
indicated that the integrated approach provided two principal benefits over the traditional method. First, the integrated
method resulted in a more precise idea of suitable sites for plantation investment that could benefit more rural people and
also lead to greater investment efficiency. Second, incorporating social preference into the GIS takes into account the crucial
element of social capital (viz., social preference), which should lead to higher levels of community acceptance of plantation
projects because those plantations would be established on socially suitable land. A second GIS exercise showed how conservation
investment decisions could be informed using the integrated method. The results of this study support the idea that GIS-aided
planning activities can be enhanced through the incorporation of social data into the analysis. When applicable, spatial data
collection efforts for GIS-based planning exercises should incorporate spatial socioeconomic data. 相似文献
610.
方力 《辽宁城乡环境科技》2006,26(1):15-17
利用ADMS-城市扩散模型和鞍山市2002年排放清单数据库,建立了鞍山市SO2(二氧化硫)空气扩散模型.同时利用2002年的气象和监测资料对模型进行了验证。结果表明:年和四季的SO2监测值和预测值的一致性较好。 相似文献