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1.
水文模拟与预测中的不确定性研究现状与展望   总被引:2,自引:1,他引:2  
尹雄锐  夏军  张翔  王晓妮 《水力发电》2006,32(10):27-31
水文模型是水循环研究、水环境保护、水资源管理等的基本工具,在过去几十年里水文模型一直是水文工作者研究的重点,而水文模型的可靠性和不确定性分析却显得不足和滞后。随着水文模型越来越复杂,在现有数据水平相对缺乏的条件下,水文模拟与预测中的不确定性日益突出。对此分析了与水文模型紧密相关的不确定性的来源,回顾了考虑不确定性的水文模拟和预测主要分析方法,并提出了未来水文模拟与预测的不确定性研究的主要内容和需要注意的问题。  相似文献   

2.
李恒山 《中国水利》2012,(12):44-46
第一次全国水利普查是一项重大的国情国力调查,县级普查机构作为普查的基础工作单元,数据质量直接关系到普查成果的总体质量。松辽流域通过关口前移,提高领导对普查工作的重视程度,加强对基层普查工作的督导检查和技术指导,做好普查培训和宣传工作,有效地保证了基层普查工作进度,确保了普查数据质量,为圆满完成第一次全国水利普查工作任务打下了基础。  相似文献   

3.
薛小红  李胜常 《中国水利》2012,(12):39-41,43
长江流域片地域广阔,经济社会发展水平极不平衡,水利普查数据成果的完整性、可靠性、准确性将极大地影响全国水利普查数据成果质量。长委普查办根据长江流域片各地区的特点及水利普查工作总体要求,通过技术研讨、经验交流、现场督导检查等多种方式有效地促进了流域片水利普查工作,汇总完成了长江流域片水利普查对象清查成果,提出了下一步水利普查数据审核的工作思路。  相似文献   

4.
淡水帷幕防治海(咸)水入侵的物理模拟试验研究   总被引:6,自引:0,他引:6  
引用地表水回灌补给地下水,在咸淡水前锋形成一道带状阻咸帷幕屏障,是防治海水入侵的一项有效工程措施. 但是,淡水帷幕的形成与咸淡水界面推移的速度和推移时间等因素之间的定量分析是人们十分关注的问题. 本文借助物理模型的模拟方法对上述问题进行了试验研究,并探索该项措施的可行性和防治效果. 该项试验可为淡水帷幕工程措施防治海(咸)水入侵技术研究提供最基本的试验室依据。  相似文献   

5.
为研究船闸运行过程中盐分的输运规律及其对淡水水域的盐度影响,建立了三维k-ε两相混合流数值模型,模型控制方程组采用有限体积法进行离散,流速与压力耦合采用SIMPLEC算法,时间项采用一阶隐式格式,流项采用二阶迎风格式,计算区域采用六面体网格划分。采用某船闸的海水入侵原型试验成果对数值模型进行了验证,闸室内盐度的模拟值与实测值吻合较好。海水入侵淡水水域模拟结果表明:上游航道盐度分布可分为异重流段、过渡段和扩散段,各段盐分输运速度依次减小;各断面的盐度呈周期性变化,在船闸运行一段时间后逐步趋于动态平衡;一个循环内的盐分入侵量在船闸运行初期较大,随着运行时间的增加逐渐减小,并趋于恒定值。研究结果可为船闸的设计与运行调度提供科学依据。  相似文献   

6.
    
The calibration of hydrological models used for flood forecasting is a difficult task that has received widespread attention. Assessing the uncertainty of flood forecasting models is fundamental to properly support decision‐making activities. Because of the demand of the different decision‐making objectives of a flood management system, we assess the uncertainty of flood forecasting models from a multiobjective perspective. Multicriteria decision analysis (MCDA) is adopted to evaluate the flood likelihood within a generalised likelihood uncertainty estimation (GLUE) framework. By combining four criteria representing different flood characteristics, the acceptability of the simulations is fully examined. The method is applied to an uncertainty analysis of a variable infiltration capacity model for the Xitiaoxi catchment. The results of 10,000 Monte Carlo simulations show that no single criterion can describe the characteristics of floods. Compared with two single‐criterion methods using the Nash–Sutcliffe efficiency, the multicriteria method shows advantages not only in assessing the prediction bounds but also in providing median GLUE estimates. The results indicate that a single criterion may be inadequate in parameter identification within the GLUE framework and that MCDA is an alternative approach to reduce the prediction uncertainty in flood forecasting.  相似文献   

7.
周灿华  樊旭  蔡平 《中国水利》2012,(12):18-20
太平闸建设时采用了较为特殊的连续反拱底板结构,该结构形式对水闸不均匀沉降适应能力较差,导致底板局部出现了裂缝.为对太平闸反拱底板进行抗裂加固,采用三维有限单元法对该闸地基系统进行应力变形分析,对工程安全状况作出评估,在此基础上进行抗裂加固方案的综合比选、优化,并对方案有效性和施工期闸墩、底板结构安全性进行复核评价,由此制定出切实可行的底板加固方案和安全措施,取得了良好的应用效果.  相似文献   

8.
The modernization of water conservancy project management is a complicated engineering system involving a management system, a management method, management personnel, the exertion of social, economic, and ecological effects, and so on. However, indices for evaluating the modernization of water conservancy project management are usually unobtainable in practical applications. Conducting appropriate extension of the classical rough set theory and then applying it to an incomplete information system are the key to the application of the rough set theory Based on analysis of some extended rough set models in incomplete information systems, a rough set model based on the θ-improved limited tolerance relation is put forward. At the same time, upper approximation and lower approximation are defined under this improved relation. According to the evaluation index system and management practices, the threshold for θ is defined. An example study indicates the practicability and maneuverability of the model.  相似文献   

9.
    
This paper aims at exploring the effects of anti-seismic reinforcement with the fiber-reinforced polymer (FRP) material bonded to the dam surface in dam engineering. Time-history analysis was performed to simulate the seismic failure process of a gravity dam that was assumed to be reinforced at the locations of slope discontinuity at the downstream surface, part of the upstream face, and the dam heel. A damage model considering the influence of concrete heterogeneity was used to model the nonlinearity of concrete. A bond-slip model was applied to the interface between FRP and concrete, and the reinforcement mechanism was analyzed through the bond stress and the stress in FRP. The results of the crack pattern, displacement, and acceleration of the reinforced dam were compared with those of the original one. It is shown that FRP, as a reinforcement material, postpones the occurrence of cracks and slows the crack propagation, and that cracks emanating from the upstream surface and downstream surface are not connected, meaning that the reinforced dam can retain water-impounding function when subjected to the earthquake. Anti-seismic reinforcement with FRP is therefore beneficial to improving the seismic resistant capability of concrete dams.  相似文献   

10.
关志诚 《中国水利》2012,(12):4-5,20
现代工程技术的长足发展,让我国西部强震区建设高混凝土面板和沥青心墙砂砾石坝成为可能。在分析国内外砂砾石坝的基础上,对砂砾石筑坝的工程特性、填筑标准与材料分区进行了研究,提出了解决其抗震稳定性的措施,包括合理的坝体材料分区设计、加强坝体抗震措施和施工技术进步等。  相似文献   

11.
基于SEAWAT建立三维海水入侵数值模型对胶州湾附近大沽河流域滨海含水层的非稳定海水入侵过程进行了模拟,并利用2010年1月1日至2018年6月1日的地下水位和Cl-质量浓度观测数据对海水入侵数值模型中的水文地质参数进行校准和验证,同时利用全局敏感性分析评估含水层渗透系数和给水度等水文地质参数以及由降水入渗补给和地下水开采组成的源汇项对海水入侵数值模型的影响。结果表明:海水入侵的发展对降水入渗补给和地下水开采最为敏感,而渗透系数的影响则相对次要;增加降水补给量和减少地下水开采量可以有效地降低未来海水入侵的范围。  相似文献   

12.
沿海缺水灌区水资源优化调配耦合模型   总被引:13,自引:0,他引:13  
张展羽  高玉芳  李龙昌  徐征和 《水利学报》2006,37(10):1246-1252
本文研究了一种基于含水层海水入侵模拟模型(子模型)和作物优化配水模型(子模型)的沿海缺水灌区水资源优化调配耦合模型,用数值方法求解了含水层海水入侵模拟子模型,并首次将基于分解协调的人工鱼群算法应用于作物优化配水的计算,通过地下水抽水量实现了子模型的耦合,利用Visual Basic6.0软件编制了耦合模型的计算程序。将模型应用于威海市节水灌溉示范区,得出其平水年(50%)、一般干旱年(75%)两种水文年型的水资源联合调配方案。结果表明基于分解协调的人工鱼群算法收敛性好,提高了计算速率,较好的解决了作物优化配水大系统中常见的变量维数高、约束方程多等问题;示范区平水年增加有效供水量997.05m3/hm2,一般干旱年增加有效供水量863.1m3/hm2,能高效利用水资源并能有效控制含水层海水入侵,经济效益和生态效益明显。  相似文献   

13.
14.
利用实测的钱塘江地形数据建立了钱塘江三维河道的计算机几何模型,并根据已有的涨潮潮位等水文信息,采用VOF方法追踪模拟水和大气的自由交界表面,对钱塘江涌潮进行了三维非稳态数值模拟。数值模拟结果与不同时刻和不同测点所测得的水文数据的对比显示,模型能较好地模拟涨潮条件下河道内流场和潮位的变化。在此基础上进行了涌潮对河道内流场影响的规律的研究。  相似文献   

15.
    
This paper applies a SWOT (strengths, weaknesses, opportunities and threats) analysis to groundwater resources management of a coastal aquifer in northern Greece typical of those subjected to seawater intrusion. SWOT analysis is found to be a useful managerial tool, incorporating interdisciplinary issues – engineering, scientific, legislative, economic and social – which are difficult to quantify, in order to identify the main environmental problem of the study area, which is overexploitation of the groundwater resources (and seawater intrusion as a consequence). Based on the main outcomes of the SWOT model, specific countermeasures are suggested in order to combat the over-pumping of the aquifer's resources which leads to overexploitation of the groundwater potential.  相似文献   

16.
郭强  李国正  陆洋 《中国水利》2012,(12):9-11,15
在水利改革发展的重大机遇期,针对一些地方仍然存在的水利重建轻管严峻现实,提出要努力探索破解建设与管理平衡发展问题的路径与对策,加强水行政管理相关体制机制和制度建设,抓好法规、规划、六类区域基本制度、收费、执法、管理体制改革以及监测等方面具体工作,转变水行政管理方式,推进水利实现跨越式发展。  相似文献   

17.
In order to evaluate the state of groundwater salination by seawater intrusion on the Lebanese coast, the region of Choueifat–Rmeyle, situated in the south of Mount-Lebanon, was chosen as a study zone. Overall, six wells were chosen and water sampling was done for three years starting from 1999 till 2002. Sampling was done on a monthly basis for ten months per year, from July till April. A complete physico-chemical analysis was done for all the water samples taken. Seawater intrusion in the Choueifat-Rmeyle region was studied through the interrelations between the chemical and physical constituents of groundwater. Results showed that the regions of Choueifat, Jiye and Rmeyle were subject to seawater intrusion. This intrusion was directly and simultaneously related to the pumping period and intensity but weakly linked to the quantity of rainfall. It was also related to the geologic nature of the study area. Furthermore, the actual intrusion in the study zone increases the already existing salinity problems. The salinity rates of wells water oscillated between 0.7 dS/m and 5.5 dS/m with the majority above 2 dS/m. This is leading to intolerable levels of water and soil salinity, inadequate for the cultivation of many crops, thus threatening their growth and production and reducing the agrodiversity in the region.  相似文献   

18.
为研究邓肯-张E-B模型参数及参数之间的交互作用对大坝变形的影响,以某均质黄土坝为研究对象,利用改进的响应面方法分析了邓肯-张E-B模型参数的全局敏感性。通过部分因子设计筛选出对土坝变形影响较为显著的5个参数为Rf、γ、φ0、Kb、K,再利用响应面方法中的中心复合设计对筛选结果做进一步的全局响应面分析,考察参数及参数之间的交互作用对土坝变形的影响。结果表明,Rf、γ、φ0是对大坝位移敏感性最强的3个参数,这3个参数之间的交互作用对于大坝变形的敏感性同样重要,且高于单个因素的敏感性,在类似工程计算中应考虑参数之间的交互作用。  相似文献   

19.
基于SEAWAT的海水入侵数值模拟   总被引:1,自引:0,他引:1  
基于三维有限差分理论,运用地下水模拟软件Visual MODFLOW中的SEAWAT模块,模拟了大连海洋大学新校区变密度条件下的海水入侵.模拟中考虑了有防渗墙和无防渗墙两种工况,并分析和比较了这两种工况下,新校区的地下水位和盐分浓度,其分布及变化规律.模拟结果表明:防渗墙对新校区地下水位和盐分浓度的分布及变化,影响都很小;盐分最终侵入校园区域,并且随着时间的增长,浓度上升至较高水平.  相似文献   

20.
相对于定性研究海水入侵的程度及规律,定量研究能更直观的给出海水入侵地区的SGD(Submarine groundwater discharge)以及流入量。选择潍坊昌邑市北部潮间带地区,布设3km长监测剖面,通过监测地下水水位、水温、以及电导率数据,运用数学方法定量估算海底地下水交换量。同时,运用计算所得结果,对研究区海水入侵情况进行评估,为将来该地区地下水监测提供科学依据。计算结果表明,潮间带流入量明显大于流出量,海水呈现朝陆推进趋势。  相似文献   

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