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961.
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
962.
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
963.
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
964.
The choice among alternative water supply sources is generally based on the fundamental objective of maximising the ratio of benefits to costs. There is, however, a need to consider sustainability, the environment and social implications in regional water resources planning, in addition to economics. In order to achieve this, multi-criteria decision analysis (MCDA) techniques can be used. Various sources of uncertainty exist in the application of MCDA methods, including the selection of the MCDA method, elicitation of criteria weights and assignment of criteria performance values. The focus of this paper is on the uncertainty in the criteria weights. Sensitivity analysis can be used to analyse the effects of uncertainties associated with the criteria weights. Two existing sensitivity methods are described in this paper and a new distance-based approach is proposed which overcomes limitations of these methods. The benefits of the proposed approach are the concurrent alteration of the criteria weights, the applicability of the method to a range of MCDA techniques and the identification of the most critical criteria weights. The existing and proposed methods are applied to three case studies and the results indicate that simultaneous consideration of the uncertainty in the criteria weights should be an integral part of the decision making process. 相似文献
965.
Maxine E. Dakins Jeffery D. Long Michael Hart 《Journal of the American Water Resources Association》2005,41(1):171-180
ABSTRACT: Collaborative watershed groups have formed at a significant rate throughout the United States in the last decade. Data on these groups, however, has been largely anecdotal and lacking in rigorous examination of the relationship between group formation, membership, process, and group effectiveness. Using a mail survey, Oregon watershed group participants were asked to identify who initiated the formation of the group, how efficiently the group formed, how the group determines membership, what decision making method the group uses, and how members perceive the group's effectiveness. Findings indicated that a majority believe that, because of their participation in a watershed group, they better understand issues in the watershed and the perspectives of others, but less than half believe that relationships with government decision makers or physical conditions in the watershed have improved. Members of citizen initiated groups rated their groups higher than government initiated groups on addressing difficult or controversial issues. Members of groups that use consensus responded most positively on whether the group gives fair consideration to dissenting opinions. Overall, groups with restricted membership systems rated themselves lowest on involving key decision making groups, timeliness in addressing issues, and overall effectiveness. These results raise concerns about this type of group membership system. 相似文献
966.
How to dissolve fixed‐pie bias in negotiation? Social antecedents and the mediating effect of mental‐model adjustment 下载免费PDF全文
Fixed‐pie bias, defined as the erroneous belief that the other negotiation party's interest is directly opposite to one's own, has been a consistent hurdle that negotiators must overcome in their efforts to achieve optimal negotiation outcomes. In this study, we explore the underlying cognitive mechanism and the social antecedents of fixed‐pie bias reduction in negotiation. Using data from a negotiation simulation with 256 participants, we found that mental‐model adjustments made by negotiators could effectively decrease fixed‐pie bias. More interestingly, we also found that negotiators were less likely to reduce fixed‐pie bias when negotiating with an in‐group member than with an out‐group member but only under a high accountability condition. Finally, we found that mental‐model adjustment mediated the effects of the aforementioned social antecedents (in‐groupness and accountability) on reduced fixed‐pie bias. We discuss the theoretical and practical implications of these findings. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
967.
Comparison of Two Spatial Optimization Techniques: A Framework to Solve Multiobjective Land Use Distribution Problems 总被引:1,自引:0,他引:1
Burghard Christian Meyer Jean-Marie Lescot Ramon Laplana 《Environmental management》2009,43(2):264-281
Two spatial optimization approaches, developed from the opposing perspectives of ecological economics and landscape planning
and aimed at the definition of new distributions of farming systems and of land use elements, are compared and integrated
into a general framework. The first approach, applied to a small river catchment in southwestern France, uses SWAT (Soil and
Water Assessment Tool) and a weighted goal programming model in combination with a geographical information system (GIS) for
the determination of optimal farming system patterns, based on selected objective functions to minimize deviations from the
goals of reducing nitrogen and maintaining income. The second approach, demonstrated in a suburban landscape near Leipzig,
Germany, defines a GIS-based predictive habitat model for the search of unfragmented regions suitable for hare populations
(Lepus europaeus), followed by compromise optimization with the aim of planning a new habitat structure distribution for the hare. The multifunctional
problem is solved by the integration of the three landscape functions (“production of cereals,” “resistance to soil erosion
by water,” and “landscape water retention”). Through the comparison, we propose a framework for the definition of optimal
land use patterns based on optimization techniques. The framework includes the main aspects to solve land use distribution
problems with the aim of finding the optimal or best land use decisions. It integrates indicators, goals of spatial developments
and stakeholders, including weighting, and model tools for the prediction of objective functions and risk assessments. Methodological
limits of the uncertainty of data and model outcomes are stressed. The framework clarifies the use of optimization techniques
in spatial planning. 相似文献
968.
Andrew Simon Natasha Pollen‐Bankhead Virginia Mahacek Eddy Langendoen 《Journal of the American Water Resources Association》2009,45(1):170-186
Abstract: Streambank erosion by mass‐failure processes represents an important form of channel adjustment and a significant source of sediment in disturbed streams. Mass failures regularly occur by a combination of hydraulic processes that undercut bank toes and geotechnical processes that cause bank collapse by gravity. Little if any quantitative information is available on the effectiveness of bank treatments on reducing erosion. To evaluate potential reduction in sediment loadings emanating from streambanks, the hydraulic and geotechnical processes responsible for mass failure were simulated under existing and mitigated conditions using a Bank‐Stability and Toe‐Erosion Model (BSTEM). Two critical erosion sites were selected from each of the three watersheds known to contribute the greatest amounts of fine sediment by streambank processes in the Lake Tahoe Basin. A typical high‐flow annual hydrograph was selected for analysis. Bank‐material strength data were collected for each layer as were species‐specific root‐reinforcement values. The effects of the first flow event on bank‐toe erosion were simulated using an excess shear‐stress approach. The resulting geometry was then exported into the bank‐stability submodel to test for the relative stability of the bank under peak flow and drawdown conditions. In this way, BSTEM was used iteratively for all flow events for both existing and mitigated conditions. On average, 13.6% of the material was eroded by hydraulic shear, the remainder by mass failures, which occurred about five times over the simulation period. Simulations with 1.0 m‐high rock‐toe protection showed a dramatic reduction in streambank erosion (69‐100%). Failure frequency for the simulation period was reduced in most cases to a single episode. Thus, an almost 90% reduction in streambank loadings was achieved by virtually eliminating the erosion of only 14% of the material that was entrained by hydraulic forces. Consequently, simulations show average load reductions of about an order of magnitude. Results stress the critical importance of protecting the bank toe‐region from steepening by hydraulic forces that would otherwise entrain previously failed and in situ bank materials, thereby allowing the upper bank to flatten (by failure) to a stable slope. 相似文献
969.
Lauren A. Patterson Martin W. Doyle 《Journal of the American Water Resources Association》2009,45(1):237-252
Abstract: After a century of evolving flood policies, there has been a steady increase in flood losses, which has partly been driven by development in flood prone areas. National flood policy was revised in 1994 to focus on limiting and reducing the amount of development inside the 100‐year floodplain, with the goal of decreasing flood losses, which can be measured and quantified in terms of population and property value inside the 100‐year floodplain. Monitoring changes in these measurable indicators can inform where and how effective national floodplain management strategies have been. National flood policies are restricted to the spatial extent of the 100‐year floodplain, thus there are no development regulations to protect against flooding adjacent to this boundary. No consistent monitoring has been undertaken to examine the effect of flood policy on development immediately outside the 100‐year floodplain. We developed a standardized methodology, which leveraged national data to quantify changes in population and building tax value (exposure). We applied this approach to counties in North Carolina to assess (1) temporal changes, before and after the 1994 policy and (2) spatial changes, inside and adjacent to the 100‐year floodplain. Temporal results indicate the Piedmont and Mountain Region had limited success at reducing exposure within the 100‐year floodplain, while the Coastal Plain successfully reduced exposure. Spatially, there was a significant increase in exposure immediately outside the 100‐year floodplain throughout North Carolina. The lack of consistent monitoring has resulted in the continuation of this unintended consequence, which could be a significant driver of increased flood losses as any flood even slightly higher than the 100‐year floodplain will have a disproportionately large impact since development is outside the legal boundary of national flood policy. 相似文献
970.
Alison H. Purcell David W. Bressler Michael J. Paul Michael T. Barbour Ed T. Rankin James L. Carter Vincent H. Resh 《Journal of the American Water Resources Association》2009,45(2):306-319
Abstract: Biological indicators, particularly benthic macroinvertebrates, are widely used and effective measures of the impact of urbanization on stream ecosystems. A multimetric biological index of urbanization was developed using a large benthic macroinvertebrate dataset (n = 1,835) from the Baltimore, Maryland, metropolitan area and then validated with datasets from Cleveland, Ohio (n = 79); San Jose, California (n = 85); and a different subset of the Baltimore data (n = 85). The biological metrics used to develop the multimetric index were selected using several criteria and were required to represent ecological attributes of macroinvertebrate assemblages including taxonomic composition and richness (number of taxa in the insect orders of Ephemeroptera, Plecoptera, and Trichoptera), functional feeding group (number of taxa designated as filterers), and habit (percent of individuals which cling to the substrate). Quantile regression was used to select metrics and characterize the relationship between the final biological index and an urban gradient (composed of population density, road density, and urban land use). Although more complex biological indices exist, this simplified multimetric index showed a consistent relationship between biological indicators and urban conditions (as measured by quantile regression) in three climatic regions of the United States and can serve as an assessment tool for environmental managers to prioritize urban stream sites for restoration and protection. 相似文献