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821.
Chris M. Alaouze 《Journal of the American Water Resources Association》1989,25(6):1163-1168
ABSTRACT: Releases from a reservoir may be allocated to a number of uses, each of which may require a given volume of water at a different reliability. The paper provides a method that can be used to estimate the volume of water associated with a given reliability for each use of water when the proportion of releases allocated to each use is known. These results can be used to evaluate the meeting of specified objectives under a published release policy derived by stationary stochastic dynamic programming. The results can also be used to solve water allocation problems when the probability distribution of available water is known (or can be estimated) and water has multiple uses, each of which has different volume and reliability requirements. 相似文献
822.
Jefferson Fox Rebekah Kanter Sanay Yarnasarn Methi Ekasingh Royce Jones 《Environmental management》1994,18(3):391-399
This research has two interrelated objectives. The first is to determine the extent to which a relationship exists between
farmer characteristics and farming practices in three villages in northern Thailand. The second is to use standard statistical
methods for incorporating spatial variables into the analysis and to assess the effects of these variables on farmer decision
making. The data base includes information on the location and size of villages, roads, streams, and fields; a digital elevation
model with information on elevation, slope, and aspect; and information keyed to individual fields on crops and cropping methods
and the ethnicity, income, and religion of farmers. The map data (517 plots) were entered into a computerized geographic information
systems (GIS). Results suggest several hypotheses about the relationships between land use and owner characteristics. More
significantly, the study concludes that spatial analysis appears to be most useful when the dependent variable is either continuous
or ordinal. The outlook is not quite as optimistic when the dependent variable is a nonordinal categorical variable. Before
spatial analysis can be applied regularly to social science data, better computational tools need to be developed. 相似文献
823.
Zachary L. McCormick 《Journal of the American Water Resources Association》1994,30(3):385-395
ABSTRACT: Agreements between states, or compacts, provide a mechanism for resolving transboundary resource issues. The twenty-two compacts allocating the water of rivers among states in the western United States are examined to provide guidance for drafters of future compacts. The method of allocation selected for a compact reflects the state's allocation of the risk of dry years. Allocations based on models have been unsuccessful. Percentage allocations are good for fairly apportioning risk, but conflict with principles of prior appropriation. Guarantees of minimum flows should be used with great care, to avoid any state becoming a guarantor of natural phenomena over which it has no control. Disputes should be anticipated, and a dispute resolution mechanism agreed upon. Arbitration or litigation are likely to prove the most politically acceptable. Compacts should be comprehensive in scope, encompassing groundwater as well as surface use. Federal claims should also be addressed, and some form of protection from subsequent changes of federal policy should be incorporated in the agreement and its ratifying legislation. 相似文献
824.
ABSTRACT: A spatial decision support system (SDSS) was developed to assess agricultural nonpoint source (NPS) pollution using an NPS pollution model and geographic information systems (GIS). With minimal user interaction, the SDSS assists with extracting the input parameters for a distributed parameter NPS pollution model from user-supplied GIS base layers. Thus, significant amounts of time, labor, and expertise can be saved. Further, the SDSS assists with visualizing and analyzing the output of the NPS pollution simulations. Capabilities of the visualization component include displays of sediment, nutrient, and runoff movement from a watershed. The input and output interface techniques/algorithms used to develop the SDSS, along with an example application of the SDSS, are described. 相似文献
825.
在煤矿里,重大灾害事故的发生尽管类型不同,但均具有共同的特性,给矿井带来的冲击与危害也难以估量、文中举出了实例两则。随着基础科学与技术的发展.以及人信对事故发生规律认识的加深.推出了矿井救灾系统,使扑救重大灾害事故从单纯经验型步入现代科学型。文章以矿井火灾扑救为例,介绍了火灾救灾专家系统的构造与作用。呼吁各级领导给于关注,以提高处理灾害事故的指挥决策能力。 相似文献
826.
本文应用最优控制理论,提出了城市防洪堤坝适时适度维护的经济决策模型。在一定条件下,给出堤坝最优反馈维护决策方法,并给出了一个简单的算例,说明了该法的应用和经济效益。 相似文献
827.
S. I. Solomon E. Basso C. Osorio H. Melo de Moraes A. Serrano 《Journal of the American Water Resources Association》1986,22(2):209-217
ABSTRACT: The construction of the Tucurui Hydroelectric Plant on the Tocantins River basin in Brazil requires flood forecasting for ensuring the safety of the cofferdam. The latter has been initially designed for a flood with a return frequency of one in 25 years. Lack of adequate forecasting facilities during the earlier stages of construction has resulted in significant damages and construction delays. Statistical forecasting models were developed by Projeto de Hidrologiay Climatologie da Amazonia (PHCA) for the purpose of preventing further damages at the site. These models are currently in use and are the subject of this paper. The application of these models during the 1980 flood season, when the highest flood on record occurred at the Tucurui site, proved of great assistance in preventing the flooding of the cofferdam. In conjunction with the development of these models a number of data collection platforms using data transmission through the GOES system were installed to provide automatically the data required for forecasting. 相似文献
828.
Nina Burkardt Berton Lee Lamb Jonathan G. Taylor Terry J. Waddle 《Journal of the American Water Resources Association》1995,31(2):187-198
ABSTRACT: We investigated the effect of technical clarity on success in multi-party negotiations in the Federal Energy Regulatory Commission (FERC) licensing process. Technical clarity is the shared understanding of dimensions such as the geographic extent of the project, range of flows to be considered, important species and life stages, and variety of water uses considered. The results of four hydropower licensing consultations are reported. Key participants were interviewed to ascertain the level of technical clarity present during the consultations and the degree to which the consultations were successful. Technical clarity appears to be a prerequisite for successful outcomes. Factors that enhance technical clarity include simple project design, new rather than existing projects, precise definition of issues, a sense of urgency to reach agreement, a sense of fairness among participants, and consistency in participation. Negotiators should not neglect the critical pre-negotiation steps of defining technical issues and determining appropriate studies, deciding how to interpret studies, and agreeing on responses to study results. 相似文献
829.
本文在分析福建全省各市、县城市生活垃圾处理现状的基础上,建立了城市经济、生活垃圾性状特征、处理技术性能、环境要求四大评判指标及标准,并运用模糊数学决策法选择了适宜福建省“十一五”城市生活垃圾处理技术路线的方案。 相似文献
830.
Developing the ethical matrix as a decision support framework: GM fish as a case study 总被引:2,自引:0,他引:2
Matthias Kaiser Kate Millar Erik Thorstensen Sandy Tomkins 《Journal of Agricultural and Environmental Ethics》2007,20(1):65-80
The Ethical Matrix was developed to help decision-makers explore the ethical issues raised by agri-food biotechnologies. Over
the decade since its inception the Ethical Matrix has been used by a number of organizations and the philosophical basis of
the framework has been discussed and analyzed extensively. The role of tools such as the Ethical Matrix in public policy decision-making
has received increasing attention. In order to further develop the methodological aspects of the Ethical Matrix method, work
was carried out to study the potential role of the Ethical Matrix as a decision support framework. When considering which
frameworks to apply when analyzing the ethical dimensions of the application of agri-food biotechnologies, it is important
to clarify the substantive nature of any prospective framework. In order to further investigate this issue, reflections on
the neologism “ethical soundness” of an ethical framework are presented here. This concept is introduced in order to provide
more structured evaluations of a range of ethical tools, including ethical frameworks such as the Ethical Matrix. As well
as examining the philosophical dimensions of the method, theoretical analysis and literature studies were combined with stakeholder
engagement exercises and consultations in order to review the Ethical Matrix from a user perspective. This work resulted in
the development of an Ethical Matrix Manual, which is intended to act as a guide for potential user groups. 相似文献