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741.
随着人民生活水平的提高,城市人均用水量逐年增加,伴随产生的生活污水已经成为不可忽视的污染源。胜利石油管理局供水公司于1993年对胜利油田的污水排放情况进行了调查,调查各单位职工住宅区和机关办公区所排放的生活污水的情况,包括排放生活污水单位的名称、人数、生活用水量、污水排放量和污水水质等,并提出了生活污水的治理对策。  相似文献   
742.
743.
ABSTRACT: A non-linear optimization model is applied to the California State Water Project (SWP) and portions of the Central Valley Project (CVP). The model accounts for the major hydrologic, regulatory, and operational features of both projects. The model maximizes long-term SWP yields over a 70-year period, using a quarterly time step. The potential for increased yield associated with a proposed facility improvement is evaluated with the model. The proposed facility is an extension of the Folsom-South Canal, which would allow water to be conveyed from the American River below Folsom Reservoir into New Melones Reservoir on the Stanislaus River or into the California Aqueduct. Model results indicate that extension of the Folsom-South Canal has the potential to increase SWP yields by 13 percent.  相似文献   
744.
ABSTRACT: A model for urban stormwater quality was developed in this study. The basis for the model is the process by which pollutants build up on the watershed surface. For the wet climate of the study site, it was assumed that there exists an interval of time over which the pollutant buildup equals the pollutant washoff (no accumulation of pollutant). The buildup model was represented by a linear function of the antecedent dry time. The buildup function was then linked with a pollutant washoff model represented by a power function of the storm runoff volume. Various time intervals for no net accumulation were tested to calibrate the model. The model was calibrated to observed data for two small urban basins in Baton Rouge, Louisiana, and model results were used to analyze the behavior of phosphorus concentrations in storm runoff from these basins over a long period of time.  相似文献   
745.
ABSTRACT: Autoregressive moving average (ABMA) models have been applied to study the flow series of the karstic springs of La Villa, Fuente Mayor (Spain), and Aliou (France). The theoretical meaning of the parameters involved in the model upon applying it to a simplified scheme of the emptying of a karstic aquifer is first analyzed. The types of transformations necessary to apply these models to the flow series that lack normality and have strong periodic components are also indicated, as are the advantages of this type of model and the physical significance of the parameters obtained, with respect to the standpoint of hydraulics, ranging from rather homogeneous aquifers (La Villa) to extremely karstic (Aliou), including aquifers with intermediate characteristics (Fuente Mayor).  相似文献   
746.
ABSTRACT: There are a large number of conceptual hydrological models available today. It is not easy to immediately identify the similarities and differences between the different models. The Swedish HBV model and the Chinese Xinanjiang model are two examples of conceptual, semi-distributed, rainfall-runoff models. The Xinanjiang model was designed for use in humid and semi-humid regions, with no routine for the snowmelt runoff, whereas the snow routine is an important part of the HBV model in many applications. The model structures of the two models may be described in four routines, compared in this paper. The integral structures of them are similar, but there are some differences, especially in the runoff production routine. The physical significance and physical definitions of some model parameters were analyzed. Both models were tested in two basins. Both models gave similar results, and both models performed well in the application. The similarity of the results obtained by different model structures leads to the following two conclusions. First, more effort should probably be spent on the improvement of input data quality and coverage than on the development of more detailed model structures only. Second, inference about basin behavior and characteristics from the values of calibrated model parameters must be made with great caution.  相似文献   
747.
ABSTRACT: Recent studies suggest that waste generation from the freshwater phase of Atlantic salmon (Salmo salar L.) production varies considerably on an annual basis. A fish farm on the West Coast of Scotland was visited regularly during a two-year period to determine inflow and outflow water quality. Waste output budgets of suspended solids (SS), biochemical oxygen demand (BOD), total nitrogen (TN), total phosphorus (TP), total ammonia nitrogen (TAN = NH3+NH4+), dissolved reactive phosphorus (DRP) and total phosphorus (TP) were produced. The annual waste loadings obtained were 71 kg TN t fish?1 yr?1 (one year of data only), 10.9–11.1 kg TP t fish?1 yr?1, 1.2–2.1 kg DRP t fish?1 yr?1, 422–485 kg BOD5 t fish?1 yr?1, 327–337 kg SS t fish?1 yr?1, and 30–35 kg TAN-N t fish?1 yr?1. Simple linear regression models relating waste parameter production to water temperature and feeding regime were developed. When compared to existing data for other salmonid production systems, greater ranges of daily waste loadings were observed. Wide variations in concentrations of these parameters during a daily cycle were also observed, suggesting that mass balance estimates of waste production will provide more robust estimates of waste output than frequent monitoring of outflow water quality.  相似文献   
748.
用灰色模型预测我国铁路水害发展趋势   总被引:2,自引:0,他引:2  
周华国  魏庆朝 《灾害学》1996,11(2):23-27
根据近15a来我国铁路水害年断道时间和断道次数的数据特点,将不同程度水害年分为三个等级。在此基础上,建立了铁路水害的灰色预测模型。并用此模型预测了近期铁路水害大小和远期的发展趋势。这对于我国铁路水害防治的宏观决策具有指导意义。  相似文献   
749.
土氡测量在地质灾害勘测中的干扰实验研究   总被引:2,自引:0,他引:2  
米秋霞  刘快胜 《灾害学》1996,11(2):47-52
对土氡勘测中来自测量过程、勘测场地条件、气象因素方面的常见干扰进行了实验研究,探讨了干扰机理,指出了定性及部分定量排除干扰的方法。  相似文献   
750.
张佳华  孔昭宸 《灾害学》1996,11(2):71-75
通过高分辨率孢粉分析及烧失量、炭屑实验结果的统计分析,结合14C、古地磁等,对北京房山东甘池15000a以来植被变化和环境变迁进行了较为深入的研究,特别强调气候变化的灾害性突变事件。初步得知约在14100~14000aB.P.前后曾出现与哥得堡反转相对应的事件,在10000aB.P.左右出现类似与新仙女木事件相对应的事件,在大约5770aB.P.和4560aB.P.左右及2850~2650aB.P.出现了大暖期的突然降温事件。  相似文献   
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