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931.
Pohchin Lai 《Environmental management》1991,15(5):595-601
Many state and local agencies have begun to adopt computer technology as a means of upgrading existing mapping and related
practices. These agencies are faced with the dualism of wanting modern technology within a traditional setting and demanding
technological independence at the same time. This article is an account of the art of technology transfers, with discussions
about the necessary ingredients and constraints in the identification, adaptation, absorption, implementation, diffusion,
and evaluation of new technologies. In general, a systematic approach towards the strengthening of endogenous capabilities
with sufficient provision for operational and policy changes may be preferable to the idea of comprehensive planning. 相似文献
932.
A new method for predicting vegetation distributions using decision tree analysis in a geographic information system 总被引:4,自引:0,他引:4
Decision tree analysis was used to predict the distribution of forest communities in an area on the south coast of New South
Wales, Australia. The analysis was carried out using a geographical information system environmental data base of those topographic
and geological variables thought to influence the distribution of vegetation and derived from cartographic sources. The resulting
maps of forest communities are of a resolution sufficient to delimit individual forest stands and contain much ecological
information. 相似文献
933.
Jacqueline Nicol 《Journal of Environmental Planning and Management》1991,34(1):37-42
The paper starts by assessing some of the needs for information management within the health service in Great Britain. Geographic Information Systems are introduced, and some of the functions such as database management, networking and overlying are described. Principally, it is argued that GIS can fill the role as a health information system, resource management system, and has the potential to assist in family practitioner monitoring and epidemiological studies. 相似文献
934.
Kathryn Connors Sasowsky Thomas W. Gardner 《Journal of the American Water Resources Association》1991,27(1):7-18
ABSTRACT: A grid cell geographic information system (GIS) is used to parameterize SPUR, a quasi-physically based surface runoff model in which a watershed is configured as a set of stream segments and contributing areas. GIS analysis techniques produce various watershed configurations by progressive simplification of a stream network delineated from digital elevation models (DEM). We used three watershed configurations: ≥ 2nd, ≥ 4th, and ≥ 13th Shreve order networks, where the watershed contains 28, 15, and 1 channel segments with 66, 37, and 3 contributing areas, respectively. Watershed configuration controls simulated daily and monthly sums of runoff volumes. For the climatic and topographic setting in southeastern Arizona the ≥ 4th order configuration of the stream network and contributing areas produces results that are typically as good as the ≥ 2nd order network. However both are consistently better than the ≥ 13th order configuration. Due to the degree of parameterization in SPUR, model simulations cannot be significantly improved by increasing watershed configuration beyond the ≥ 4th order network. However, a range of Soil Conservation Service curve numbers derived from rainfall/runoff data can affect model simulations. Higher curve numbers yield better results for the ≥ 2nd order network while lower curve numbers yield better results for the ≥ 4th order network. 相似文献
935.
C. G. Keyes 《Journal of the American Water Resources Association》1977,13(5):917-925
ABSTRACT: A need for the prudent design and critical analysis of all weather modification efforts was expressed by the attendees of the June 1974 Governors' Weather Modification Conference in Sioux Falls, South Dakota. The attendees also expressed a need for an organization to coordinate and cooperate in intrastate, interstate and possible international weather modification activities, particularly in view of the growing importance of agricultural production, energy demand and domestic water supply. The North American Interstate Weather Modification Council (NAIWMC) was ratified on January 17, 1975, in Denver, Colorado, with its main purpose to achieve and maintain state and local control of such activities while endeavoring to attain a high degree of legislative uniformity and an effective information exchange mechanism. The need, goals, and objectives of the newly-created Council are summarized herein. The by-laws of the Council are presented according to the articles adopted at the organizational meeting. Membership in the Council is available to all states of the United States of America, Mexico, and all provinces of Canada. The officers of the Council are elected from its membership according to the regions of weather modification activities. A summary of the Council's progress at performing the purposes is presented in this paper. Definition of the users involved in the North American Interstate Weather Modification Council has been achieved during the early activities of the Council. The Council's views on federal and state weater modification legislation are presented according to position statements that have been adopted by the member states and provinces. 相似文献
936.
R. Kent Jones John T. Dale 《Journal of the American Water Resources Association》1977,13(5):1007-1019
ABSTRACT: Worldwide development of water resources and control of pollution would be improved by the ability for direct, multilateral communication between workers in the dozens of different language communities involved. Current language-based problems which should be eliminated include (1) incomplete diffusion of scientific knowledge, (2) technical inbreeding, (3) unsatisfactory international conferences, (4) money wasted on translation, and (5) unstandardized technical terminology. General education in a common second language for international use can eliminate these conditions. Ethnic languages are not qualified for this purpose, because of their national biases and extreme learning difficulties. The Esperanto language is free of these limitations, and its application is recommended as a means for improving the overall performance of the industry. 相似文献
937.
Carl Griffith 《Environmental management》1980,4(1):21-25
The analytical structure of environmental impact assessment is continually changing as the applicability of established techniques from other fields and the development of novel methods become known. This paper illustrates the applicability of using existing data bases, through a geographic information system, for theex ante evaluation of land use disruption. More specifically, the Canada Geographic Information System was employed to retrieve, to analyze, and to produce land capability statistics and land use maps for the proposed Glengowan dam and reservoir. 相似文献
938.
Paul W. Mielke Charles F. Chappell Lewis O. Grant 《Journal of the American Water Resources Association》1972,8(6):1219-1224
Principal component analysis is used to investigate density requirements of wintertime orographic cloud seeding experiment precipitation sensor networks. Three passes in the vicinity of Climax, Colorado are studied. The eighteen or more evenly spaced precipitation sensors of each pass are almost completely described by three principal components. These three principal components appear to represent (i) mean precipitation, (ii) slope orientation to storm systems, and (iii) elevation. Evaluation of these principal components is implemented with two distribution-free tests, a proportionality test and the runs test. The results of this study suggest that the loss of experimental information caused by low density precipitation sensor networks may be of little consequence. 相似文献
939.
940.
水环境承载能力调控与水质信息系统模式的探讨 总被引:1,自引:0,他引:1
水环境承载能力是可持续发展理论的重要体现,它具有很强的动态、空间时空、水量水质兼顾、补偿等特性。建立水质信息系统基础平台,科学地利用和调控水环境承载能力,实现水环境保护目标的实现。本文就水环境承载能力调控与水质信息系统模式的建立进行了分析研究,并结合中国实情提出了建模总体框架。 相似文献