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961.
This paper is based on a shopping study carried out by the Department of Geography, University of Utrecht, during 1983. It is concerned with retail planning research for larger regions and starts with a state of the art review of retail planning research in the Netherlands. The aim, in developing a new research strategy, was to reduce time and costs through using computer facilit es for both data handling and data collection. There is discussion of methodology and some outcomes to demonstrate the possibilities of the strategy.  相似文献   
962.
ABSTRACT: The Pawtuxet River flows from a relatively rural area through some of the more highly industrialized sections of Rhode Island. During its journey, the river receives many municipal, industrial, and ground water sources of metal constituents. The present report is the first in a two part series in which the water quality of this urban river was evaluated by a chemical monitoring study of the sources, transport mechanisms, and fate of cadmium, chromium, copper, lead, and nickel in the river. The second paper will use the chemical data to derive and calibrate a steady-state water quality model for this river. The metal concentrations In the river tended to increase from the headwaters to the mouth with river stations nearest to point source outfalls showing elevated values. In some sections of the river, levels of a few of the metals could not be explained by the point sources; and other inputs, including sediment resuspension, axe proposed to make up this apparent unbalance. The ability of a municipal secondary treatment plant to remove metals was demonstrated, and the tie-in of the effluent from a major chemical company to the plant did not cause any observable deterioration in treatment efficiency.  相似文献   
963.
964.
ABSTRACT: A 1984 survey of water resources personnel was conducted to determine the current and future uses of mathematical models in planning, design and operations of water resources systems. Eighty-six percent of those responding indicated they have used mathematical models in the last year. Lack of appropriate data, inadequate time and funding to do the modeling and lack of models that represent the “real world” situation were the most frequently mentioned constraints to model use. Microcomputers were seen as having a positive influence on mathematical model use in water resources.  相似文献   
965.
ABSTRACT: Mandatory water conservation in the form of restrictions on outdoor watering, car washing, and recreation was implemented in the City of Austin, Texas, during the summers of 1984 and 1985. Three different stages of restrictions were implemented limiting the number of watering hours per day, as well as a restriction that allowed lawn watering once every five days according to the last digit of the street address, Intervention analysis using a transfer function-noise model of daily water use is applied to assess the impact of the restrictions. Compared to a peak water use rate of about 170 MGD, it is shown that mandatory restrictions in 1984 reduced water use by an average of 13.5 MGD, while similar restrictions during the summer of 1985 reduced usage by an average of 5.5 MGD. Lawn watering restrictions on a five-day cycle produced a corresponding five-day cycle in water use of more than 10 MGD in amplitude in 1985. An alternative lawn watering scheme that eliminates this cycle is prescribed.  相似文献   
966.
Models for pollutant runoff can be useful in water quality management planning if appropriately structured for the problem at hand. Accordingly, a “top-down” approach is proposed for the examination of extant pollutant runoff models. The approach consists of the identification of objectives and attributes that reflect the needs of planners and decision makers when these models are used for water quality management planning. Ideally, the attributes should concern the effect of model information on improved decision making and the cost of model application. Practical difficulties with the first attribute necessitates substitution of surrogate attributes reflecting model appropriateness, resolution, and uncertainty. Common pollutant runoff models, in particular export coefficients and hydrology-driven simulation models, are found to have serious weaknesses on some of the attribute scales. The “top-down” approach leads to a set of desirable pollutant runoff model attributes; alternate modeling techniques are thus examined in order to identify promising future directions for model development. The focus of this examination is phosphorus, due to its importance in the eutrophication of surface waters. Models for both sediment-attached and dissolved phosphorus are considered. Among the conclusions is the belief that the partial contributing area concept can yield an effective yet simple simulation despite the variable and complex nature of runoff.  相似文献   
967.
ABSTRACT. The critical role of political processes in water resource projects has recently been placed in a new perspective [Hall, 1970]. The “political hassle” period of institutional interaction which serves to resolve political conflicts over such aspects as organizational growth and survival, responsibility for economic liabilities, and responsibility for economic benefits, requires systematic analysis in order to improve our capability to implement water projects. Failure to properly assess the political aspects of a proposed water project may result in extensive delays with significant economic losses. The complexities associated with water use and re-use have created the need for new institutional arrangements which can more effectively function to implement policies and programs. One tool which has recently become available for the research investigator concerned with institutional interactions and political processes associated with water resource projects is the technique of computer simulation of such institutional interaction. In theory, this new approach will enable the investigator to assess the political feasibility or political acceptability of a proposed water project given existing institutional structures. Furthermore, the investigator has the opportunity to experiment with new and innovative institutional arrangements which may in turn enhance the political acceptability of a proposed project. The specific material presented within this paper reports upon the validation of an existing computer simulation model designed to replicate political interactions in resource allocation problems-including water resource problems. This validation effort is done by taking an actual water problem and comparing what the political simulation models predicts in terms of political outcomes with what actually takes place. The case study in question is the formulation and legislative development of the Michigan Bond Issue for Water Pollution Control.  相似文献   
968.
Computer simulation of river basin hydrology has rapidly progressed from an interesting academic exercise to a practical engineering procedure of increasing utility. Mathematical models of the many interrelated processes which occur in a basin have been developed along with efficient numerical procedures for their solution. The present paper is concerned with a particular model which has been used to describe the transformation of a temporally and spatially varying rainfall into a time history of stage and discharge on a flood plain. Although developed principally as a model of the physical processes involved, it is envisioned that the model can serve as one component of an information system for flood plain planning and management. The model consists of the following elements: (i) a rainfall simulation which generates stochastic inputs to the model according to specified rainfall statistics, (ii) a catchment-runoff model which converts the rainfall to surface runoff, (iii) a flood stage model which converts the surface runoff to time histories of flood stage and discharge. The model has been used to investigate the effect of various structural flood control measures in a basin and, in particular, to establish frequency-stage information for each of these. Of particular interest in development of the model have been recurring and partially unanswered questions relative to the proper balance among availability of data for use in the model, data requirements of the model and the objectives of the outputs produced by the model.  相似文献   
969.
为确保高校社区安全管理的精准、高效、便捷,将社区网格化管理的理论和技术引入高校安全管理中,构建“防灾型”高校社区安全管理模式,结合“微安全”微信平台,链接社区全体人员。根据布拉德安全曲线,将“防灾型”高校社区安全管理模式定位在杜邦安全管理第三阶段;采用问卷调查的形式对管理效果进行考察。研究结果表明:事故发生率降低61.42%,事件处理效率提高74.05%,居民满意度达80.2%;“防灾型”网格社区安全管理模式能够对高校安全信息进行系统化管理,实现管理层与执行层的扁平化、联动管理;安全事故伤害率越来越低。  相似文献   
970.
Even though the academic press recognizes generational diversity and its consequences, the related findings are fractured, and research is incomplete regarding methodology and theoretical background. In adopting a social identity perspective concerning groups and self‐conception, we argue that the social identity perspective is in line with generational identity theory. Employing a cognitive mapping method (repertory grid technique, mixed methods), the present study taps into three generations (Baby Boomers, Generation X, and Generation Y) of Belgian managers' minds and demonstrates how they perceive their own and the two other generations. Our research reveals that perceptions of their own and other generations may direct social categorization and generational stereotypes of the in‐group and out‐group(s), that some of these stereotypes can be enacted, and that generational stereotypes do not necessarily coincide with age‐based stereotypes. Several metapatterns in the stereotypes are revealed as well. Hence, we contribute to the emerging field of research that calls for an identity‐based approach rather than a cohort‐based approach to generations and that validates the argument that generations as a workplace phenomenon must be considered a legitimate phenomenon. Insights into generations as social categories give a richer view of the interrelationships between generations in multigenerational situations at work.  相似文献   
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