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1.
ABSTRACT: Local governments often face environmental problems that cross political boundaries. The onus for solution usually falls on the moat severely affected jurisdiction, others do nothing until impacted. Resolution of these problems requires cooperation across political boundaries which means that local governments must be persuaded first that there is a problem, and second that action is required to solve it. This paper presents a method to supply low cost, credible information that can be used to achieve consensus on problem solution. A case study of a lake water quality management problem is described. Formative evaluation techniques was adapted to provide a minimum of evidence which was then used to persuade less impacted local jurisdictions to cooperate in the problem solution.  相似文献   

2.
ABSTRACT: Water resource development has progressed to the stage where various human factors are now being considered in reservoir design and operation. The introduction of human factor objectives complicates the problem since they are noncommensurate with other objectives and they are difficult to identify quantitatively. Some of the problems that now arise concern the proper methods for consideration of several different, sometimes subjectively identified, objectives in reservoir planning. The classical systems analysis approach to decision making for multiple objective problems is outlined and the inherent difficulties associated with multiple objectives and subjective estimates are identified. Techniques being used in reservoir design and operation are reviewed and discussed. An alternate technique for considering noncommensurate, subjectively identified, objectives, which relates the objectives in terms of real trade-off costs and eliminates the need for a priori estimates of objective worth is then presented. The method is illustrated with three examples, including a reservoir operation problem and a cooling tower design problem.  相似文献   

3.
以资源环境经济学、循环经济学作为理论基础,采用实证与规范经济分析法,从理论和实践两个层面系统研究首都经济圈水资源环境,提出水资源循环经济发展模式,用以解决首都经济圈水资源与经济发展的矛盾.重点分析了该区水资源问题及其对国民经济的影响,阐述了以经济手段为主的具体对策,旨在从根本上解决水资源问题,促进区域和谐发展.  相似文献   

4.
The basic theories and fundamental assumptions usually employed in the solution of unsteady groundwater flow problems are reviewed critically. The best known method of analysis for such problems is based on the Dupuit-Forchheimer approximation and leads to a nonlinear parabolic differential equation which is generally solved by linearization or numerical methods. The accuracy of the solution to this equation can be improved by use of a different approach which does not employ the Dupuit Forchheimer assumption, but rather is based on a semi-numerical solution of the Laplace equation for quasi-steady conditions. The actual unsteady process is replaced by a sequence of steady-state conditions, and it is assumed that the actual unsteady flow characteristics during a short time interval can be approximated by those associated with “average” steady state flow. The Laplace equation is solved by a semi-discretization method according to which the horizontal coordinate is divided into subintervals, while the vertical coordinate is maintained continuous. The proposed method is applied to a typical tile drainage problem, and, based on a comparison of calculated results with experimental data, the method is evaluated and practical conclusions regarding its applicability are advanced.  相似文献   

5.
ABSTRACT. Flood detention reservoir design is a common problem encountered by engineers and others involved with water resources problems. This paper presents a method by which the volume of flood storage required for a single reservoir or a series of reservoirs may be estimated without using numeric flood-routing techniques. The proposed procedure requires a minimum of computations and is most applicable to preliminary design situations where a high degree of accuracy is not required.  相似文献   

6.
ABSTRACT: This paper explores some of the advances of the boundary element method, as applied to ground-water problems, during the last five years. Although the method is still somewhat limited compared to solution by finite elements, the range of solutions has increased considerably. Diffusion and advection-diffusion solutions are done efficiently. These include the incorporation of inhomogeneity, anisotropy, and nonlinear diffusion. The difficult problem of stream-aquifer interaction is an important application as it is much easier to follow a free surface with its multiple configurations. The application must be able to cycle between ground-water connection and disconnection with the stream and include seepage surfaces. Flow in fractured media is a natural application where the flow in fractures can usually be treated without a computational exception in spite of extremely high aspect ratios. The case of seawater intrusion forms a type of free surface problem and thus is a case for which the method has special advantages. For these and other applications the boundary element method provides an inexpensive technique for calculation where the data preparation and setup time is minimal. In most of these cases, programs can and have been written on microcomputers.  相似文献   

7.
An Experiment in Participative Environmental Decision Making   总被引:2,自引:0,他引:2  
Summary The paper presents a method of participatory decision-making involving the authorities at local level, experts and the public. It studies how to solve the problems caused by the heterogeneity of the parties taking part in the decision-making process. The method builds on mutual learning and consideration among the participants following a systematic approach led by a moderator. The method was tested at a workshop simulating a real-life situation. The test case studied at the workshop was the problem of identifying the best site for a low and intermediate level radioactive waste repository among three alternatives. The learning phase was the Krško Nuclear Power Plant cooling problem. The results show that the participants were able to reach agreement on the prioritisation of the alternatives and to end up with suprisingly complex and fully reasonable decision models. We believe that this was achieved particularly due to the well defined procedure that guided the decision-making process, and the ability of all participants to see the influence of their views on the decision model.  相似文献   

8.
Cheng, Chuntian, Jianjian Shen, Xinyu Wu, and Kwok-wing Chau, 2012. Short-Term Hydroscheduling with Discrepant Objectives Using Multi-step Progressive Optimality Algorithm. Journal of the American Water Resources Association (JAWRA) 48(3): 464-479. DOI: 10.1111/j.1752-1688.2011.00628.x Abstract: With increase in the number and total capacity of hydropower plants in power systems, optimality algorithms with a single objective are not suitable for optimizing the operation of complex hydropower systems to meet complex demands. Hydropower plants should prioritize discrepant objectives, such as peak regulation and maximizing generation during solving of optimal operation problems of hydropower systems. In this article, we present a multi-step progressive optimality algorithm (MSPOA) for the short-term hydroscheduling (STHS) problem to improve the quality of optimal solutions and enhance the convergence speed of progressive optimality algorithm (POA). In MSPOA, the original problem is first decomposed into a sequence of problems with the longer time steps. Next, the problem with the longest time step is solved, and the optimal solution is used as the initial solution for the problem with the second longest time step. This process proceeds until the original problem with the shortest time step is solved. The proposed discrepant-objective method and solution technique are tested for two types of hydroelectric systems. The results show that MSPOA can give better solutions and cost less time than POA due to enlarging feasible range of decision variables and reducing the number of computational stages. Discrepant objectives among hydropower plants can express the operation characteristics of complex hydropower systems more accurately than unique objective or multiple objectives.  相似文献   

9.
This study examines the use of spatial optimization techniques for multi-site land-use allocation problems (MLUA). 'Multi-site' refers to the problem of allocating more than one land-use type in an area, which are difficult problems as they involve multiple stakeholders with conflicting goals and objectives. Spatial optimization methods consist of (1) an optimization model and (2) an algorithm to solve the model. This study demonstrates a goal-programming model to solve the MLUA problem. The model is solved using both simulated annealing and genetic algorithms. Special attention has been given to introduce a spatial compactness objective in the model. It is shown that the compactness objectives in the optimization model generate compact patches of the same land use for using both the simulated annealing procedure and the genetic algorithm. In addition, it appears that using the proper settings of the compactness objectives, connectivity between patches of land use is promoted. The method is tested for a fictive study and then demonstrated for a real case study, both measuring 20 × 20 cells. The genetic algorithm generally performs better than simulated annealing in terms of solution time and achieving compactness.  相似文献   

10.
The specter of environmental calamity calls for the best efforts of an involved public. Ironically, the way people understand the issues all too often serves to discourage and frustrate rather than motivate them to action. This article draws from problem-solving perspectives offered by cognitive psychology and conflict management to examine a framework for thinking about environmental problems that promises to help rather than hinder efforts to address them. Problem-framing emphasizes focusing on the problem definition. Since how one defines a problem determines one's understanding of and approach to that problem, being able to redefine or reframe a problem and to explore the “problem space” can help broaden the range of alternatives and solutions examined. Problem-framing incorporates a cognitive perspective on how people respond to information. It explains why an emphasis on problem definition is not part of people's typical approach to problems. It recognizes the importance of structure and of having ways to organize that information on one's problem-solving effort. Finally, problem-framing draws on both cognitive psychology and conflict management for strategies to manage information and to create a problem-solving environment that not only encourages participation but can yield better approaches to our environmental problems.  相似文献   

11.
农村剩余劳动力的产生有其特定的背景和原因,同时也与"三农"问题息息相关,农村剩余劳动力问题长期受到学术界的关注。在计算安徽省六安市剩余劳动力存量的基础上,采用灰色关联分析方法,对影响六安市农村剩余劳动力的因素进行分析,并结合区域实际情况,探讨由剩余劳动力过多所产生的一系列问题,提出剩余劳动力转移的对策。  相似文献   

12.
通过对土地资源可持续利用意义的分析,结合我区土地资源利用的现状,阐述我区土地资源利用面临的各种问题及解决的方法,提出一些急需解决的理论问题及实际工作中面临的难题;同时也提出了一些解决问题的对策和土地可持续利用的思路。  相似文献   

13.
It has been documented in the literature that, in some cases, widely used regression‐based models can produce severely biased estimates of long‐term mean river fluxes of various constituents. These models, estimated using sample values of concentration, discharge, and date, are used to compute estimated fluxes for a multiyear period at a daily time step. This study compares results of the LOADEST seven‐parameter model, LOADEST five‐parameter model, and the Weighted Regressions on Time, Discharge, and Season (WRTDS) model using subsampling of six very large datasets to better understand this bias problem. This analysis considers sample datasets for dissolved nitrate and total phosphorus. The results show that LOADEST‐7 and LOADEST‐5, although they often produce very nearly unbiased results, can produce highly biased results. This study identifies three conditions that can give rise to these severe biases: (1) lack of fit of the log of concentration vs. log discharge relationship, (2) substantial differences in the shape of this relationship across seasons, and (3) severely heteroscedastic residuals. The WRTDS model is more resistant to the bias problem than the LOADEST models but is not immune to them. Understanding the causes of the bias problem is crucial to selecting an appropriate method for flux computations. Diagnostic tools for identifying the potential for bias problems are introduced, and strategies for resolving bias problems are described.  相似文献   

14.
A significant research problem is the assessment of impacts associated with growth and/or decline in a regional economy. A relevant method for analyzing such problems is the Leontief input/output model. Associated with these models are economic multipliers measuring total changes in sales, income, and employment. In this paper, the author contends resource multipliers are equally relevant. The specific form of these multipliers are defined. Water multipliers for a two-county region in central Nevada are presented and their uses described.  相似文献   

15.
ABSTRACT. Evidence from 1969 studies in Virginia and Ohio suggests that neither community leaders nor the general public are likely to define water related problems as major problem areas. An examination of the components of a social problem tends to indicate that water problems have not moved beyond a level of minimal public concern. When respondents were willing to describe existing or potential water problems, perceptions as well as possible solutions were described in abstract rather than action-oriented terms. It is suggested that efforts to eliminate water resource problems are not likely to be effective until public concern moves to motivational and behavioral levels.  相似文献   

16.
ABSTRACT A mathematical model was developed to solve a steady free surface flow problem and a rapid drawdown problem in a two-dimensional porous medium. The same problem was also solved by an analogue device and excellent agreement was found to exist between the two solutions. This paper contains the formulation of the numerical problem from first principles and a discussion of measures that had to be taken in order to assure numerical stability and proper convergence of the solution. Although the scope of this study was limited to a two-dimensional flow case, the elements of simulation discussed are general in nature and applicable to three-dimensional problems. It was demonstrated that numerical solution can be obtained for the position of the free surface at given time intervals, for the piezometric head distribution within the flow field and for flow quantities across given boundaries. In addition, the mathematical model will permit consideration of nonhomogeneous or anisotropic characteristics of the porous medium, without difficulty. It is concluded that mathematical models, incorporating some or all of the techniques discussed in this paper, in conjunction with some analogue control device, can be very efficient and reliable tools for solving complex porous flow problems, including those which, so far, have eluded comprehensive analysis, due to physical and/or cost limitation.  相似文献   

17.
This article is the first in a series of three. These articles were prepared to document the growth management process undertaken in Teller County, Colorado, USA. In this article, an 11-step method for landscape planning is proposed. In step 1, an issue, or set of related issues, is identified as posing a problem and/or opportunity to people and/or the environment. In step 2, a goal, or several goals, is established to address the problem or opportunity. In steps 3 and 4, inventories and analyses of biophysical and sociocultural processes are conducted, first at the regional level and then at the local level. Step 5 involves detailed studies (such as suitability analyses) that link the inventory and analysis information to the problems or opportunities and goals. Detailed studies link regional and local information to specific sites. Thus, this method involves a regional-local-specific site hierarchy. In step 6, concepts are developed that lead to a landscape plan in step 7. During step 8, the plan is explained through a systematic educational and citizen involvement effort to the affected public. In step 9, detailed designs are developed that again are explained to the specific individuals who will be impacted by the designs. It is in step 10 when the plan and designs are implemented. Step 11 involves the administration of the plan. The method is illustrated through an example of growth management planning for Teller County and the city of Woodland Park, Colorado. Paper 1 in a series of 3.  相似文献   

18.
Many environmental problems are longitudinal collective action problems. They arise from the cumulative unintended effects of a vast amount of seemingly insignificant decisions and actions by individuals who are unknown to each other and distant from each other. Such problems are likely to be effectively addressed only by an enormous number of individuals each making a nearly insignificant contribution to resolving them. However, when a person’s making such a contribution appears to require sacrifice or costs, the problem of inconsequentialism arises: given that a person’s contribution, although needed (albeit not necessary), is nearly inconsequential to addressing the problem and may require some cost from the standpoint of the person’s own life, why should the person make the effort, particularly when it is uncertain (or even unlikely) whether others will do so? In this article I argue that justifications for making the effort to respond to longitudinal collective action environmental problems are, on the whole, particularly well supported by virtue-oriented normative theories, on which character traits are evaluated as virtues and vices consequentially or teleologically and actions are evaluated in terms of virtues and vices. If ethical theories are to be assessed on their theoretical and practical adequacy, and if providing a compelling response to the problem of inconsequentialism is an instance of such adequacy, then this is a reason for preferring virtue-oriented ethical theory over non-virtue-oriented ethical theories, such as Kantian, act utilitarian, and global utilitarian theories.  相似文献   

19.
《环境质量管理》2018,27(4):55-63
This study examines the challenges posed by solid waste by assessing the disposal methods practiced by residents in the Ijebu‐Ode Local Government Area (LGA) in Ogun State, Nigeria. Primary data were obtained through questionnaire administration. One out of every 10 houses was selected for sampling in six randomly selected wards of Ijebu‐Ode LGA. Three hundred and twelve questionnaires were administered on heads of households. Information elicited from the respondents covered solid waste disposal practices, the rationales behind those practices, and the respondents’ perceptions of environmental problems, including environmental health problems that could emanate from such practices. Data on environmental problems and environmental health problems measured on a 5‐point Likert scale were analyzed using Aggregate Weighted Mean Index. The computed Environmental Problem Indices (EPIs) and Environmental Health Problem Indices (EHPIs) were used to determine the severity of the respective challenges. The results established that blockage of drains with an EPI of 4.15 was a very severe environmental problem and flood hazard with an EPI of 3.55 was a severe environmental problem resulting from solid waste disposal practices. Incidence of malaria and cholera, with EHPIs of 2.85 and 2.56, respectively, were however ranked as not severe environmental health problems. The study concluded that solid waste disposal practices in Ijebu‐Ode LGA were unhygienic and unsafe, hence the need for government intervention to ensure the adoption of the necessary measures toward a safe and healthy environment.  相似文献   

20.
The difficulty and complexity in evaluating water resource problems is becoming more evident to management with each passing year. Decisions are required sooner, in more detail, with some background—and yet cost more to evolve. One potential method to arrive at solutions at least more rapidly and in more detail is via simu- lation. A manager may evaluate many alternative solutions to his problem—provided an evaluated simulation system is at his disposal. One such system under development is a highly flexible computerized model system for evaluating real economic/technical applicability of desalting to a selected area. The Economic Evaluation Model System (EEMS) was initially conceived during 1968 and the first version was completed in 1969. This system represents the combination of technical, environmental and economic functions into an interrelated system, which allows the user to examine a broad range of water related problems—oriented toward the applicability of desalting as an additional or alternative source of water. The major thrust of the development of the system thus far, however, has been with the methodology involved and further refinements and extensions of the system are recognized and planned for in future research and development.  相似文献   

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