基于协商对策的群决策模型及其在跨流域调水方案优选中的应用

本文分析了调水方案决策的多目标性和群决策性特点,研究基于"满意原则"的多人多目标决策模型。重点针对决策者利益的有限冲突性,提出基于协商对策的多目标群决策模型。以辽宁省"引细入汤"工程方案决策为例,构筑了由冲突双方和仲裁方组成的三方仲裁局势,并详细阐述模型的求解过程。该模型在满足公平性原则前提下,兼顾了冲突双方及整体利益,具有较强的可操作性和实用性。     

基于协商对策的多目标群决策模型及其在白石水库调度中的应用

针对水库兴利调度决策的多目标性和群决策特点,重点研究了基于协商对策的多目标群决策模型。以白石水库为工程背景,分析了决策群体间利益和冲突性,构筑了由冲突双方和仲裁方组成的三方仲裁局势,详细阐述了模型的决策过程。通过对该水库的可行兴利调度方案集进行优化决策,最终得到满意方案,为白石水库的实际运行提供依据。文中研究与应用的决策模型也可用于类似的决策分析中。     

基于两层决策模型的东庄水库导流方案优选

水利工程建设条件复杂,导流方案影响因素多、参数组合多、备选方案丰富,利用一般的多目标决策模型进行方案优选存在困难。在优化导流方案决策目标的基础上,针对导流标准、围堰类型、导流洞布置等特征引入趋同分组方法,结合多目标决策方法建立基于两层决策的施工导流方案优选模型。针对东庄水库施工导流的多个导流方案,建立分组决策模型,利用两层决策模型优选导流方案,所得优选方案反映了工程特征。     

区间直觉模糊信息下的水利工程应急方案投影群决策模型

为了更准确高效地处理应急方案群体决策问题,考虑集结算子集结含零值的决策信息会得到不准确的结果,提出基于区间直觉模糊信息和投影法的应急方案群决策模型。首先,由区间直觉模糊集理论和投影法,构建多目标优化模型求解群体最优集结信息;然后采用区间直觉模糊熵确定指标的属性权重,使用基于方案投影的贴近度确定最优方案;最后通过案例分析,验证该决策模型的有效性。研究结果表明:灾害社会影响和善后处理对应急决策起到了重要作用;投影决策模型提高了决策过程的准确性和效率性,具有较好的适用性和推广性。     

施工导流方案的多目标总体综合评价方法

施工导流方案的选择是一个复杂的多目标决策问题，针对施工导流工程的特点，建立了多目标决策模型；利用改进层次分析法（IAHP），确定各目标在评价对象中的权重，再根据多目标决策理论，将其转化为单指标决策模型；利用总体综合评价方法对方案进行评价，算例验证了该方法的可行性，分析中以为导流方案选择提供决策支持。     

基于灰色关联度和主成分投影法的节水灌溉工程投资方案优选

在节水灌溉项目投资方案优选的决策过程中,所依赖的信息是“部分完全的”或称“贫信息性”,这正是多个方案优选决策的“灰色性”。投资方案的优选决策是一项复杂的、多项因素的工作,要考虑的目标很多,其评价因素和优选结论都具有“不确定性”,这实际上是一个多目标的决策问题。针对多个投资方案的优选问题,引入灰色关联度和主成分投影法,通过建立决策模型对投资方案进行优选,提高了优选的精确性和客观性,并通过实例说明采用该方法解决多目标的方案决策是可行的。     

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。     

水利工程投资的不确定多目标群决策支持

针对水利工程投资的多目标性、不确定性等特点，研究了不确定多目标群决策模型在水利工程投资方案选择中的应用，并结合实例分析，表明不确定多目标群决策模型可以有效解决水利工程投资决策中面临的半结构化问题，能够为水利工程投资提供有效的决策支持。     

大连市水资源利用与宏观经济协调发展规划多目标群决策模型与方法

以大连市水资源开发利用与宏观经济协调可持续发展为研究背景，建立了大连市宏观经济水资源发展规划多目标群决策模型。根据该决策模型具有的多层次多目标多决策者的特点，结合陈守煜建立的工程模糊集理论与切比雪夫决策方法，提出了模糊切比雪夫多目标群决策方法。结果表明，该决策模型与模糊切比雪夫多目标群决策方法是有效和可行的。     

基于TOPSIS法的城市内涝事件应急群决策研究

为满足城市内涝的应急决策需求,减少内涝损失,提出了基于TOPSIS法的城市内涝事件应急群决策模型。一方面,针对城市内涝事件的发生具有不确定性、复杂性和阶段性的特点,采用区间灰数描述待评价应急方案的评价指标属性值和评价指标权重;另一方面,为有效协调多目标之间的错综复杂的关系,引入TOPSIS法进行方案评价,根据加权规范化矩阵确定方案的正理想解和负理想解并计算相对接近度,并与决策者权威性权重融合得到综合群体决策相对接近度,根据可能性矩阵的排序向量的大小对方案进行排序择优。通过案例分析结果表明:模型具有可行性和现实意义,能够为城市内涝事件的应急决策提供理论参考。     

Call for Papers

正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc.     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

库水波动下库岸边坡地下水浸润线解析解及误差分析

解析法是库岸边坡地下水浸润线计算中便于实际应用的方法,但该方法须基于若干假定并对潜水运动基本方程线性化后才能求解。针对各假定和线性化过程建立不同的地下水渗流数学模型,用解析法和有限元法解答上述数学模型,分析各误差大小及其规律。结果表明：库岸垂直处理带来的误差要小于方程线性化处理和不考虑非饱和渗流带来的误差,而且它们都随渗透系数变大而减小;在三峡库区库水调度情况下,假定库水位等速变化带来的误差对大多岸坡而言可以忽略;计算库岸边坡地下水浸润线时,解析法只适用于水位变化幅度相比含水层厚度较小,且几何边界规则、岩土结构简单、岩土体渗透性较好时的情况。     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

Changes in Summer Irrigated Crop Area and Water Use in Southeastern Turkey from 1993 to 2002: Implications for Current and Future Water Resources

Changes in summer irrigated cropland acreage and related water use are estimated from satellite remote sensing and ancillary data in semi-arid Southeastern Turkey where traditionally dry agricultural lands are being rapidly transformed into irrigated fields with the help of water from the Euphrates-Tigris Rivers. An image classification methodology based on thresholding of Landsat NDVI images from the peak summer period reveals that the total area of summer irrigated crops has increased three-fold (from 35,000 ha to over 100,000) in the Harran Plain between 1993 and 2002. Coupled analysis of annual irrigated crop area from remote sensing and potential evapotranspiration based estimates of irrigation water requirements for cotton indicate a corresponding increase in agricultural water use from about 370 million cubic meters to over one billion cubic meters, a volume in accordance with the state estimates. These estimates have important implications for understanding the rapid changes in current agricultural withdrawals in Southeastern Turkey and form a quantitative basis for exploring the changes in future water demands in the region. For example, expansion of irrigated lands have led to a steady decrease in potential evaporation due to increased roughness and decreased humidity deficit in the Harran Plain. Assuming that the changes in future evaporation conditions will be of similar nature, water use for irrigation is expected to decrease over 40 percent in future irrigation sites. Incorporating this decrease in overall planning of the irrigation projects currently under construction should lead to improved management, and by extension, sustainability of water resources in the region.     

SPATIAL AND TEMPORAL WATER QUALITY VARIABILITY IN AQUATIC HABITATS OF A CULTIVATED FLOODPLAIN

The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L^?1, the median total phosphorus was 0.29 mg L^?1 and the median total nitrogen was 1.56 mg L^?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd.     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

Spatio‐temporal variation of gross CO2 and CH4 diffusive emissions from Australian reservoirs and natural aquatic ecosystems,and estimation of net reservoir emissions

Carbon dioxide (CO₂) and methane (CH₄) diffusive emissions were measured during two field surveys in Queensland and Tasmania, Australia, using the floating chamber method. Bubbling and degassing emissions in 2010 were estimated in Koombooloomba Dam reservoir using only inverted funnels and gas concentrations, respectively. A total of 14 reservoirs and 16 rivers and lakes were sampled from 2006 to 2010. Spatial variation was substantial within each water body, as well as between them. The main drivers of diffusive emission variation were physiographic region and climate, with a clear demarcation being observed between diffusive emissions from tropical Queensland and temperate Tasmania, and between the humid West Coast Range (Tasmania) and dry Central Plateau (Tasmania). Higher CO₂ and CH₄ diffusive emissions were observed during the dry season, when long water residence times would promote organic matter degradation. Estimated total gross emissions, including diffusive, bubbling and degassing emissions, for Koombooloomba Dam reservoir were about 1.5 × 10⁶ t CO₂eq km² per year, or 24 × 10⁶ t CO₂eq per year. This corresponds to a plant emission factor of 3.18 kg CO₂eq MWh^?1. Using an estimate of terrestrial emissions derived from literature data for the Tully River catchment area, rough estimated net emissions from the catchment area are about 44 kt CO₂eq per year, or 5.83 kg CO₂eq MWh^?1, which is in the lower range of the studied reservoirs.