Methodology for Estimating Streamflow by Water Balance and Rating Curve Methods Based on Logistic Regression

Both water balance (WB) and rating curve (RC) are methods for estimating streamflow. The first is mostly used to estimate reservoir outflows, while the second is usually adopted in hydrometeorological network streamflow gauges. While WB uses hourly collected data, the RC estimates streamflow using current water level and extrapolation techniques. The objective of this study was to analyze variations in the reservoir’s hourly outflow at Queimado Hydroelectric Power Plant (HPP Queimado) and to propose a method to evaluate whether the estimate of the daily outflows, obtained by the WB method, is similar to the flow values obtained at a conventional station. The logistic regression (LR) model was used because it is a method that adopts binary, categorically dependent variables to identify the event of interest. The results showed that the values of streamflow, obtained from an average of two daily readings, were a good representation of the flows in the region. The LR was able to identify atypical data, especially in the rainy season. This means that data consistency analysis can be faster and safer, when adequately employed and considering the proposed conditions, contributing to both management policies and the management of water resources.

     

基于粗糙数BWM_ ELECTRE方法的水库移民安置区优选

移民安置是水库工程建设的重要组成部分,而移民安置区的选址直接关系到移民安置工作的成败。通过引入粗糙数的概念,对不同决策者的主观偏好进行整合,得到以粗糙数形式表示的群体偏好信息,用最优最劣法(BWM)确定指标权重,并采用基于粗糙数的消去与选择转换法(ELECTRE)对备选方案进行排序,构建了基于粗糙数BWM_ELECTRE方法的水库移民安置区优选模型。实例分析验证了该模型的可行性和有效性。     

黄土区SCS-CN模型径流曲线数计算方法研究

美国农业部开发的SCS-CN模型是较为常用的一种径流计算方法。模型中的CN值是模型中反映土地利用、土壤类型和土壤前期含水量的一个综合参数,其值的选择对于准确计算地表径流具有重要意义。利用黄土高原地区杨青川流域、燕沟流域和西川流域不同土地利用类型42场模拟降雨的径流资料,应用平均值法、中值法、算术平均值法、S对数频率分布法和渐近线法5种方法计算CN值,并利用CN值反推径流深。采用均值比较、模型评价指标的方法比较了5种方法计算的径流深与实测值的差异,根据相对隶属度最大最优原则确定最优计算方法。结果表明:在杨青川流域,最优的计算方法是平均值法,燕沟流域和西川流域的最优计算方法则是中值法,不同流域同一计算方法确定的同一土地利用类型CN值差异较大;单独进行草地和裸地的评价分析时,草地的最优计算方法是平均值法,裸地的最优计算方法是算术平均值法,不同土地利用类型CN值的最优计算方法不同。     

An Optimization Approach for Multi-Sectoral Water Supply Management in the Greater Beirut Area

This paper presents a model that was developed and applied to serve as a water supply multi-sectoral decision support system for water resources management taking economic and socio-environmental factors into consideration. The applicability of the model was tested in the Greater Beirut Area by examining future supply-demand management alternatives and quantifying the cost-benefit of viable policies. The effect of eliminating a particular source to account for resources depletion and public acceptability, as well as increased returns from water use were proven to affect greatly the water allocation scheme. The model can also be a useful tool to assess the effect of decreasing unit costs from water supply options (desalination) and the resulting breakeven point, and the effect of increased water demand due to unplanned growth (tourism).     

基于指标权重的喀斯特地区水资源承载力评价

采用向量夹角余弦法和均方差法确定指标权重,运用多目标灰色关联投影法对贵州省各地区的水资源承载力进行了排序.     

基于Shapley-Value的梯级水库联合调度效益分配方法探讨

目前梯级水库在联合调度时由于补偿效益分配制度上的不合理,致使一些调节性能较好的电站在联合调度过程中得不到公正的对待,从而影响了这些电站对联合调度的积极性.针对上述问题,以三峡梯级和清江梯级五库联合调度为例,引入博弈论中的Shapley-Value法对联合调度所产生效益分配方法问题进行了探讨.结果表明:该方法不仅具有很强...     

New Approaches for Estimation of Monthly Rainfall Based on GEP-ARCH and ANN-ARCH Hybrid Models

Accurate estimation of rainfall has an important role in the optimal water resources management, as well as hydrological and climatological studies. In the present study, two novel types of hybrid models, namely gene expression programming-autoregressive conditional heteroscedasticity (GEP-ARCH) and artificial neural networks-autoregressive conditional heteroscedasticity (ANN-ARCH) are introduced to estimate monthly rainfall time series. To fulfill this purpose, five stations with various climatic conditions were selected in Iran. The lagged monthly rainfall data was utilized to develop the different GEP and ANN scenarios. The performance of proposed hybrid models was compared to the GEP and ANN models using root mean square error (RMSE) and coefficient of determination (R²). The results show that the proposed GEP-ARCH and ANN-ARCH models give a much better performance than the GEP and ANN in all of the studied stations with various climates. Furthermore, the ANN-ARCH model generally presents better performance in comparison with the GEP-ARCH model.     

An Ultimatum Game Theory Based Approach for Basin Scale Water Allocation Conflict Resolution

Increasing water consumption via competitive demands has resulted in serious water conflicts and the subsequent environmental crisis in the Gavkhouni Watershed with the Gavkhouni swamp in the most downstream located in the central part of Iran. In this research, a two-player ultimatum game theory approach is adopted to not only address the water conflicts with the purpose of environmental reclamation of the drying swamp, but also to ensure economic satisfaction for the upstream landowners and farmers. The Ministry of Energy (MoE) and its subsidiary regional water authority represent the responsible organizations for providing water while the Ministry of Agriculture (MoA) is the primary body in charge of water consumption in the watershed. MoE and MoA are considered as two players in the game, whereas MoE has more power than MoA in terms of allocating water. Five strategies are studied namely: 1 and 2) decreasing water allocation to irrigated agriculture as much as the annual shortage of the Gavkhouni swamp with and without compensation to MoA (D-L), 3 and 4) decreasing water allocation to irrigated agriculture twice as much the annual shortage of the swamp with and without compensation for MoA (D-2 L) and 5) giving up Gavkhouni swamp’s reclamation plan (D). Moreover, three scenarios regarding the relations between environmental and agricultural utilities are designated. According to the results, D-2 L with paying compensation to MoA is chosen as the best alternative in scenario 1 when the environmental utility was assumed to be greater than the agricultural utility. Ultimatum Game Theory has no final solution for scenarios 2 and 3 where the environmental utility is considered to be equal and smaller than agricultural utility. The swamp’s annual environmental water shortage as 324 million cubic meters is supplied by application of both strategies D-L and D-2 L. Ultimatum Games are efficient in assessment of water conflicts to resolve them through careful and planned negotiations.     

Combination of Multiple Data-Driven Models for Long-Term Monthly Runoff Predictions Based on Bayesian Model Averaging

Water Resources Management - Accurate and reliable long-term runoff forecasting is very important for water resource system planning and management. This study utilized three data-driven models to...     

A Hybrid Model Based on Variational Mode Decomposition and Gradient Boosting Regression Tree for Monthly Runoff Forecasting

Water Resources Management - Accurate and reliable monthly runoff forecasting is of great significance for water resource optimization and management. A neoteric hybrid model based on variational...     

基于PPA-极值理论的大坝变形预警指标拟定

大坝变形预警指标估计对实现大坝安全监控具有重要意义。基于极值理论,提出了POT变形预警模型,利用广义帕累托分布对大坝变形监测数据分布的尾部特征进行拟合分析,基于PPA和信息熵理论构建多测点变形熵,结合大坝失事概率,完成对其预警指标的估计。以某混凝土大坝为例建模验证,结果表明:POT模型可以更好地刻画变形监测数据分布的尾部特征,对预警指标的估计偏于安全。     

An Enhanced Beetle Antennae Search Algorithm Based Comprehensive Water Quality Index for Urban River Water Quality Assessment

Water Resources Management - Urban river not only has the important function in urban hydrological environment, but also is an area for entertainment. Water quality assessment is the core technique...     

Assessing a Multivariate Approach Based on Scalogram Analysis for Agricultural Drought Monitoring

Due to the complexity of agricultural drought, univariate indices may not be suitable for assessing its impacts comprehensively. The main objective of this study was to develop a new multivariate drought index using the Scalogram concepts, in which the input data weights and their cluster separation were performed based on the entropy theory and fuzzy k-means algorithm, respectively. The newly developed index, named as SCI index, integrates the four weighted individual quantitative indicators such as the difference between precipitation and potential evapotranspiration (D_i), the moisture departure (d_i), the Soil Moisture index (SMI), and the Vegetation Condition Index (VCI) to quantify agricultural drought in monthly and annual timescales in the various climate conditions of Golestan province, Iran. Next, the Composite Drought Index (CDI) was calculated for the selected stations by the same variables in the SCI index as an input. According to the results a good agreement and a high behavioral similarity for the identifying moisture conditions was found between SCI index and CDI index and even other well-known drought indices such as SPEI and SPDI. But the intensity with extremes of wet and dry conditions in the CDI significantly were more than the SCI index and other ones. Comparing results obtained by the Standardized Yield Index (SYI) for rainfed wheat with the SCI index showed that at most stations when a severe drought as happened in 2000–2001 and 2007–2008, severe crops losses also occurred. The flexible structure of SCI index provides a comprehensive approach to quantify agricultural drought and can be adapted to characterize other types of drought on a practical basis.     

豫西黄土丘陵区退耕还林还草对策探讨

结合豫西黄土丘陵区自然、社会经济特点分析了退耕还林还草存在的主要问题，从自然条件和技术经济等方面论述了退耕还林还草的可行性。针对本区立地条件提出了退耕还林还草的对策，探讨了本区退耕还林还草配置模式、乔木树种的配置方案和牧草种植模式。     

A Stochastic Approach for Seasonal Water-Shortage Probability Forecasting Based on Seasonal Weather Outlook

This study proposed a stochastic approach to forecast water-shortage probabilities for the coming three months in central Taiwan. Monte Carlo method is used to repeat random sampling from the seasonal weather outlook. For each Monte Carlo trial, the monthly rainfalls and monthly mean temperatures for one to three months ahead in eleven upstream catchments of central Taiwan can be obtained. Further, the disaggregation model is used to convert the monthly values into daily rainfall and temperature series. The HBV-based hydrological model uses the daily series to simulate daily inflows for each catchment as the input of system dynamic model for simulating the water budget of water resources system. After all the Monte Carlo trails, the monthly water-shortage probabilities for one to three months ahead can be calculated. The results reveal that the proposed approach can reasonably forecast the water-shortage conditions for one to three months ahead, which are beneficial for regional drought warning and decision support of drought-disaster prevention.     

黄土边坡剥落病害处治方案的熵权双基点决策法

针对影响边坡剥落因素的复杂性和不确定性,充分利用地质资料、施工条件、工程经济及环境影响等综合因素,运用熵权双基点的概念,构造了一个黄土边坡剥落病害处治方案的优选模型。该模型合理融合客观评价和主观评价,克服了传统评估方法中主观确定权数的缺陷,在很大程度上保证了优选结果的正确性。通过实例分析,证明剥落病害处治方案熵权双基点决策法,具有较强的识别评判能力和简便、定量、严密的特点。该方法对其他综合评价工作也有一定的借鉴意义。     

基于Matlab 7.0的梁板结构可靠度指标求解

可靠性指标β的求解是梁板结构可靠度分析中的重点和难点,Matlab计算软件由于其功能强大及简单易懂的突出特点,在β计算中具有明显优势。结合大秦线盖板涵钢筋混凝土盖板实例,分别应用JC法和Matlab优化法,编写Matlab计算程序,对β求解,快速、准确得出计算结果。     

An Approach to Elaborate Priority Preorders of Water Resources Projects Based on Multi-Criteria Evaluation and Fuzzy Sets Analysis

Water scarcity is one important problem among many water problems that are present today and will be even more noticeable in the future. Many developing countries have investigated water resources projects to satisfy their demand in water. There is no enough financial capability to execute all these projects in one lot, so it is important to elaborate a priority execution plan related to these projects to identify the sequence of projects to be executedin order of priority (priority preorder). First the conditions required for an accurate priority preorder elaboration are outlined and the evaluations of the different goals or criteria are presented. Then an appropriate methodology to determine the priority preorders of water resources projects with respect to the defined criteria is developed. Lastly, an example of application is given in order to examine the various steps of the proposed methodology and its applicability is discussed.     

基于ArcEngine洪灾避难路径选择可视化方法研究

为了在洪水灾害发生时尽量减少人员损失,保证人民的生命财产,避难路径的选择尤为重要。以辽河洪水风险图为基础数据,在Visual Basic环境下,利用ArcEngine 9.2组件为开发辅助工具,通过已有的避难场所初选方案,根据路权分析模型和在ArcGIS环境下建立的道路网络数据集实现最佳避难路径的生成,为灾民提供准确的撤离路线,达到快速撤离的目的。     

基于区间数理论的施工初期导流标准多属性决策

施工导流系统的复杂性和不确定性使得初期导流标准决策指标难以精确表达。考虑决策指标信息的随机性,基于区间数理论建立施工导流标准多属性决策模型。首先提出施工导流标准决策指标区间数估计的方法,然后基于信息熵理论给出了区间数指标的客观熵权计算方法,以结合主观权重来确定综合权重,进而阐述了基于区间数可能度的施工导流标准方案排序方法,最后将该模型应用于西南某大型水电工程的初期导流标准决策,并与多目标决策结果进行了对比,计算分析表明,决策模型及方法是有效的、适用的,为施工初期导流标准多属性决策提供了新的途径。