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801.
Ralph K Davis Darryll T Pederson 《Journal of the American Water Resources Association》1996,32(1):107-115
ABSTRACT: Ground-water level decline patterns in parts of Nebraska conform to the circular island concept of Bredehoeft et al. (1982), which indicates how water is derived by wells developed in a circular island. If elongated, the center of the island corresponds to a regional ground-water divide while the shoreline corresponds to a regional river. In both versions, ground-water table elevation is a function of recharge and transmissivity. A dynamic equilibrium exists such that the gradient of the water table will convey all recharge to discharge areas. Withdrawals of ground water result initially in mining, with a new equilibrium attained when pumping equals capture. During early development, capture is an important source of water in discharge areas, while mining is more significant in recharge areas. The pattern observed in many areas shows the greatest ground-water level decline in the vicinity of ground-water divides and the steepest gradient near regional rivers. A similar pattern has been observed adjacent to the Arkansas River in south-central Kansas. Similar decline patterns can be modeled for a hypothetical ground-water basin. This is of major importance to water-resource managers because it dictates that management programs be applied to the entire hydrologic system. 相似文献
802.
ABSTRACT: Recent developments in multiple objective decision making methods presented in the upcoming sequence of research papers are evaluated and compared with respect to their usefulness in addressing challenging problems in water resources management. Because many of the decision making techniques originated in the field of operational research, the historical evolution of this field is outlined and the current need for developing a wide range of techniques for employment in strategic decision making is pointed out. Informative attributes for classifying decision making techniques are given to allow a practitioner to select decision aids that can best model the key characteristics of the particular problems under study. By systematically applying a wide variety of multiple objective decision making techniques to many different kinds of water resources problems, the authors of the papers clearly demonstrate the effectiveness of utilizing these methods for assisting in making both tactical and strategic decisions in water resources management. 相似文献
803.
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
804.
The Hawaii Environmental Simulation Laboratory (HESL) was a three year experiment in improving governmental decision making by developing better research methodologies for use by public decision making bodies and community organizations. Funded through the University of Hawaii by the Ford Foundation (FF) and the National Science Foundation (NSF), HESL conducted its researchinteractively with the intended users of its products. This paper sets the HESL experiment in the context of recent trends in applying better methodology to environmental decision making and involving citizens in these decisions. It describes the HESL effort, and then draws conclusions about both the effectiveness of the experiment and the way it was conducted, providing information that may be useful in guiding university groups, public agencies, and community organizations pursuing similar objectives. 相似文献
805.
Wade H. Andrews J. Paul Riley Malcolm B. Masteller 《Journal of the American Water Resources Association》1980,16(2):194-202
ABSTRACT: This work was the development of a model for analyzing the social components of a flood control or sociological-hydrologic decision process. A general conceptual system was developed from the study of an actual decision. Mathematical values were determined for the social and behavioral variables and these elements were transposed into a mathematical linear model providing a set of equations from which the system could be simulated with the computer. 相似文献
806.
Gerald J. Bakus William G. Stillwell Susan M. Latter Margaret C. Wallerstein 《Environmental management》1982,6(6):493-504
The two major processes of decision making, behavioral interactions and decision analysis, are discussed. Comparisons are made between the Delphi and NGT methods of behavioral interaction. Three different types of decision analysis are compared, including the Goals Achievement Matrix, Concordance Analysis, and the Simple Multi-Attribute Rating Technique. Decision making problems characteristic of environmental studies are reviewed. A method of decision making that combines the best qualities of other methods is suggested. The overall purpose of this paper is to make the technical knowledge of decision making useful to environmentalists, businessmen, citizens, and politicians, and to improve the process of policy making in environmental studies. 相似文献
807.
ABSTRACT. Society has long sought to maximize the welfare of its members by allocating its limited resources so as to provide maximum satisfaction. As long as all of the values that society gains or loses are measured in the market place in terms of price, the process of maximizing through economic models is relatively straightforward. In fact, however, the total value that society receives from the use of its resources is not completely measured through the private market transactions. There are some values created which are external to the market system. The resulting underinvestment in natural resources by the private sector necessitates the entry of the public sector. The presence of intangible benefits and intangible costs has long been recognized, but completely satisfactory methods for including these in the quantitative analysis of benefit-cost have not been developed. Some progress has been made in including recreational values in project analysis via the expenditures method, the Gross National Product method, consumer surplus method, cost method, market value method, and monopoly and discriminating monopoly methods, but little has been done in the area of aesthetic values. Techniques for including such values in project evaluation need to be further researched. Tradeoff models developed by market researchers, the advertising industry, social psychologists and sociologists may have some applicability. Methodology for including proposed multiple objective functions in project analysis is also a critical need. 相似文献
808.
J. Ernest Flack 《Journal of the American Water Resources Association》1971,7(3):517-520
ABSTRACT Water resources planning has emphasized the consideration of alternatives in the formulation of goals and objectives. With greater availability of data and projection models, optimization of plans is now much nearer to accomplishment. In contrast to these favorable aspects of planning, increased complexity of plans and large number of alternatives serving differing sets of goals have extended the time horizons from initial plan formulation to eventual implementation. In this paper a man-machine strategy is proposed to reduce the time required for decision making and conflict resolution. A panel of representatives of the decision makers, influentials and publics involved are selected and brought through a series of dynamic planning steps that simulate real time decision making. Computer interaction graphics is used to visualize the decision making process and to illustrate where and why conflict arises. A mechanism for resolution of conflict and retention of consistency in policy formulation using a cognograph is described. 相似文献
809.
Raul E. Filardi Walter J. O'Brien 《Journal of the American Water Resources Association》1975,11(1):131-147
ABSTRACT. Middle and high management levels within water utilities would find their decision making activities greatly enhanced if provided with a set of techniques having the following characteristics: (1) the ability to procure information and knowledge about real-life systems, (2) the ability to promote analysis of the real life system and (3) the capacity to gauge the impact of decisions. A model/simulation is presented, having the capability to mime operational aspects of water supply systems. The simulation produces time series of what are considered relevant operational variables. These series are amenable to analysis of both static and dynamic effects of alternative policies, changing environmental conditions and varying parametric specifications. Because of its modular structure and the ad hoc programming language utilized, it offers great flexibility. The model/simulation allows extensions, deletions and modifications without consequent reformulation or extensive reprogramming. It performs a number of statistical tests useful for its own verification and validation. Also available are a suggested methodology and procedures for model use, possible difficulties with data gathering and operation, plus an idea of what cannot be done with the currently extant model version. 相似文献
810.
Marcelo Cerucci Jon M. Conrad 《Journal of the American Water Resources Association》2003,39(5):1167-1180
ABSTRACT: Riparian buffers are considered important management options for protecting water quality. Land costs and buffer performance, which are functions of local environmental characteristics, are likely to be key attributes in the selection process, especially when budgets are limited. In this article we demonstrate how a framework involving hydrologic models and binary optimization can be used to find the optimal buffer subject to a budget constraint. Two hydrologic models, SWAT and REMM, were used to predict the loads from different source areas with and without riparian buffers. These loads provided inputs for a binary optimization model to select the most cost efficient parcels to form a riparian buffer. This methodology was applied in a watershed in Delaware County, New York. The models were parameterized using readily available digital databases and were later compared against observed flow and water quality data available for the site. As a result of the application of this method, the marginal utility of incremental increases in buffer widths along the stream channel and the set of parcels to form the best affordable riparian buffer were obtained. 相似文献