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601.
本文通过对近年来国内外对网络环境下信息检索语言理论及应用性成果的研究,分析了检索语言的研究进展,并尝试性地对网络环境下这一领域的发展趋势进行了展望。 相似文献
602.
通过阐述高等院校教育信息资源库建设过程中存在的问题,分析了信息资源库的建设、管理、应用问题,按照提出问题、分析问题、解决问题的方法,观点鲜明的指出了作者对信息资源库建设与应用的一些理性思考.文章认为高等院校应该在重视信息资源库建设的基础上,更加重视资源的管理和应用. 相似文献
603.
Lance A. Waller Brett J. Goodwin Mark L. Wilson Richard S. Ostfeld Stacie L. Marshall Edward B. Hayes 《Environmental and Ecological Statistics》2007,14(1):83-100
We present an exploratory analysis of reported county-specific incidence of Lyme disease in the northeastern United States
for the years 1990–2000. We briefly review the disease ecology of Lyme disease and the use of risk maps to describe local
incidence as estimates of local risk of disease. We place the relevant elements of local environmental and ecological variables,
local disease incidence, and (importantly) local disease reporting in a conceptual context to frame our analysis. We then
apply hierarchical linear models of increasing complexity to summarize observed patterns in reported incidence, borrowing
information across counties to improve local precision. We find areas of increasing incidence in the central northeastern
Atlantic coast counties, increasing incidence branching to the north and west, and an area of fairly stable and slightly decreasing
reported incidence in western New York. 相似文献
604.
Assessing Suitability for Conservation Action: Prioritizing Interpond Linkages for the California Tiger Salamander 总被引:3,自引:0,他引:3
CHRISTOPHER R. PYKE† 《Conservation biology》2005,19(2):492-503
Abstract: Conservation organizations and public agencies are interested in identifying and prioritizing areas for conservation action, often acquisition or easements. Typically, this requires the use of uncertain data and vaguely defined decision criteria. I developed a decision support system to address these uncertainty issues and assist in evaluating conservation opportunities for the endangered California tiger salamander ( Ambystoma californiense ) in Santa Barbara, California. Functionally defined planning units were used to aggregate data on land suitability, land cover change, salamander presence, and movement risk along potential linkages between breeding ponds. I used a fuzzy-logic-based inference engine to evaluate the planning units and rank the relative suitability of interpond linkages for conservation action. The sensitivity of the rankings was considered with respect to uncertainty in salamander occurrence data and the relationship between land-cover-change threats and site suitability. All linkages were substantially degraded, but five areas were consistently identified with high relative suitability for conservation action despite differences in assumptions and uncertainty in biological data. The combination of functionally defined planning units and a fuzzy-logic-based decision support system provides a general framework for considering the suitability of sites for conservation action. 相似文献
605.
根据中国可持续发展信息共享系统建设的要求,针对全国农村生态环境质量的信息特征,描述了“全国农村生态环境质量信息共享系统”的设计背景、系统总体结构、数据组织形式以及信息表达方式,并探讨了实现信息共享系统的结构化设计、系统网络的集成式服务模型、动态网页制作、元数据库构建、统计信息的空间化表达方法、空间统计分析和信息共享安全保障等信息共享的关键技术途径。 相似文献
606.
607.
解决中国农村环境保护信息非对称性的方法探索 总被引:8,自引:1,他引:8
基于对世界银行项目——“中国乡镇工业企业环境行为研究”的子项目“乡镇工业企业污染控制报告制度研究”在江苏省丹阳市的实施过程的研究,发现污染控制报告会在乡镇环境管理中有着良好的社会效益、经济效益和环境效益,不失为一种解决农村环境保护信息非对称性的优选方法。 相似文献
608.
程琼 《湖南环境生物职业技术学院学报》2006,12(1):42-46
2002年7月美国通过了关于会计和公司治理一系列重大改革的索克斯法案(SOX Act),该法案以加强公司治理、强化信息披露为核心,主要内容是强化对高级管理人员的监管和防止外部审计失败.本文简单系统地介绍和分析了该法案中重要措施的相关内容和出台的原因,以期对我国当前公司治理和审计业发展有所启迪和帮助. 相似文献
609.
W. Ritchie 《Journal of Coastal Conservation》1995,1(1):63-76
Oil spill contingency plans are available for most coastlines but the amount of useful environmental data is variable. The
information should be held on a GIS base. High risk areas should be identified and the pre-existing store of environmental
knowledge should be commensurately extensive and should be available in considerable spatial detail. Contingency plans still
depend on basic lists of coastal types as defined by static, sediment based shoreline characteristics. There is a lack of
dynamic, process information. TheBraer oil spill of 1993 provides a case study of the application of sound coastal geomorphological and ecological data to impact
assessment. Monitoring of the ecological effects of this massive oil spill reinforces other research which indicates that
most coastlines can recover naturally from oil spills, and that oil spill clean up techniques may not necessarily benefit
rapid shoreline recovery. Although pre-existing environmental informations is important, the key decisions must be taken quickly
and are frequently judgmental and, therefore, place a premium on gathering appropriate scientific expertise to the site of
the spill as soon as possible and with sufficient powers to affect both the oil spill response, to initiate early surveys
of damage and to facilitate the initial monitoring programme. 相似文献
610.
F. Veloso-Gomes F. Taveira-Pinto Luciana das Neves Joaquim Pais Barbosa Carlos Coelho 《Journal of Coastal Conservation》2004,10(1):43-52
The entire northwestern coast of Portugal is undergoing severe erosion and there are several areas at high risk of erosion.
Commonly considered as a problem—because it jeopardizes human development along the coast—erosion is indeed a natural process
of sediment redistribution. This paper presents a brief analysis of erosion driving forces and the subsequent state of vulnerability
that coastal segments between the mouth of the River Douro and Cape Mondego are facing. The paper also discusses erosion risk
levels, low or high, and the subsequent questions whether there are populations, economical assets or natural habitats at
risk and/or areas prone to coastal flooding. Main challenges and future trends along the study area are identified in the
light of understanding the underlying causes of conflicts and what realistically can be achieved given the morphodynamics
and hydrodynamic processes, human development established along this coastal segment and the existing policies. 相似文献