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在充分考虑水资源系统中供需水不确定性的基础上,基于多目标规划、模糊规划和区间规划原理,以经济效益、社会效益和环境效益最大为目标,以需水量、可供水量和不同子区用水部门间的用水公平性为主要约束,构建一种适用于多水源、多子区、多用户的考虑供需水不确定性的多目标模糊规划模型,以期通过平衡水资源配置系统中用户配置水量、缺水风险与系统收益三者的关系,实现系统综合效益最大。模型以衡水市历年供水、用水及社会经济等数据确定规划年的水资源参数及经济参数,采用区间参数反映系统中的不确定性,通过引入模糊隶属度函数,利用两步交互式算法,将多目标规划转化为单目标规划进行求解,以2025年为衡水市规划水平年,得到规划水平年下的11个子区、4种水源、4个用水行业的最优配水方案。结果表明:本研究制定的水资源优化配置方案可实现“外调水优先利用、地下水控制利用”,同时考虑用水的公平性约束后,在缺水条件下可有效控制水资源向每立方米水效益高的区域和部门流动,有利于多区域、多部门共担缺水风险;该水资源优化配置方案可有效缓解衡水市水资源供需矛盾,实现多水源和多目标之间的协同互补。研究成果可为河北省其他县域的水资源优化配置提供技术参... 相似文献
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针对水资源系统中供需水存在的不确定性和随着时间推移呈现的动态性,基于黑龙江省历年供水、用水及社会经济等数据确定规划年的水资源参数及经济参数,采用区间参数反映系统中的不确定性,利用多阶段随机规划反映水资源配置中的动态性,进而建立了多水源、多用水户的区间多阶段随机规划模型,模型通过平衡水资源配置系统中用户配置水量、系统风险与系统收益三者关系,可实现系统最大经济效益。利用该模型对黑龙江省水资源配置问题进行研究,结果表明:规划年黑龙江省生活、工业和生态用水均可以得到满足,农业用水在丰水年基本得到满足,枯水年缺水量为15.32亿~49.40亿m3,与现状年相比,农业缺水得到一定程度的缓解;水源供给方面,地表供水比例稳步提升,可以较好保护地下水源。 相似文献
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宁夏干旱缺水且发展不均衡,以水定需是必然选择。本文针对宁夏水资源条件和经济社会特征,构建协调公平与效率的“四水四定”优化模型,开展全区“四水四定”方案分析。模型以用水总量红线指标为水资源刚性约束,根据区域发展战略确定刚性保障需求,通过水与“四定”协调关系分析得出经济社会发展和用水效率可行变化范围。以2019年为现状、2025年为目标年,采用模型协调优化得出“四定”规模控制目标,以及分行业和区县的用水总量控制指标。结果表明,在全区73.27亿m3用水总量和41.5亿m3耗水约束下,满足全面小康的“四定”规模为750万人、5481亿元GDP、84.7万hm2灌溉面积和791 km2建成区面积。通过对比分析方案的公平性和效率提升状况,揭示了不同行业、区域的水量流转方向,表明约束设置对结果有显著影响,可为区域经济社会发展和水资源管控决策提供参考。 相似文献
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再生水是城市的“第二水源”,加强再生水配置利用对优化供水结构、增加水资源供给、缓解水量供需矛盾以及保障水生态安全具有重要意义。科学预测城市再生水需求是提高污水资源化利用水平的重要基础。在区域水资源需求分析基础上,充分考虑工业生产、城市杂用、河道补水、农林灌溉等4大领域的水量和水质需求特点,提出考虑水质与水价的分领域再生水需求预测技术框架。首先考虑水质影响,引入再生水可替代率指标,分析水资源需求总量中可由再生水供给的水量;其次,考虑自主定价模式下再生水价格对用户需求的影响,建立“补贴-价格-需求”模型,计算不同补贴情景下区域再生水的需求量;最后,应用于宿迁市中心城市。结果表明:在规划年2025和2030年的再生水利用率目标要求下,采用中等补贴情景能在有效推广再生水利用的同时兼顾政府财政压力,再生水需求量分别可达10 095×104和13 387×104 m3。本研究进一步拓展了城市再生水需求量预测的理论方法,也为宿迁市再生水利用配置提供了科学依据。 相似文献
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吉林市城区水资源联合调度通过地表水、地下水联合调度完成。利用水资源配置模型进行水量调度,模型根据第二松花江城区段当前水量、地下水可开采量与未来时段用水要求,在预测来水基础上,通过水量平衡计算,给出吉林市各水厂供水量、地下水抽水量、市界断面过水流量、供水区可供水量与亏水量等相关调度建议,利用模型模拟,完成吉林市城区水资源联合调度。 相似文献
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水资源总量控制是水资源管理的主要手段,针对区域来水、取用水分开统计,导致区域来水、取用耗排水、断面出境水量不闭合问题,本文从水量控制核算的角度出发,构建基于水循环转化的水资源配置模型,通过模拟区域水资源取用耗排过程下的水循环过程,以区域来水和出境断面水量双向控制方法核算区域水量取用情况。以天津市为例,在全境多年平均来水42.1亿m~3(其中外调水14.7亿m~3)情景下,2020年水平年天津市取用水、耗水和排水等总量闭合控制阈值分别为38.25、22.0和16.25亿m~3,出境水量为22.1亿m~3,根据水资源实际管理需求,模型给出了各区县不同水源和行业相应的控制阈值,研究成果可为水资源消耗双控行动、最严格水资源管理和节水型社会建设提供科学支撑。 相似文献
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结合项目区工农业特点及水资源分布情况,水资源及其开发利用现状,并在分析和评价水资源可供水量及存在问题的基础上,按照社会经济可持续发展和生态环境对水资源的要求,根据当地水资源总量(9 500万m3)控制、水资源利用效率水平等作为规划目标的约束条件,构建改进后的SWAT模型,对模型参数进行率定和水文过程模拟。采用水量平衡与模型模拟方法计算出现状年(2012年)的ET值和不同规划年2种水文年型的目标ET值。在供需水预测的基础上,设置不同规划情景条件下的各行业节水方案。方案比选后提出推荐方案,并据此分析各乡镇的需水和耗水情况,进而给出近期规划年2020年和远期规划年2030年各乡镇的需水量和耗水量。 相似文献
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水资源短缺及其水生态环境问题,已成为严重制约中国经济发展的重要因素。因此,如何对有限的水资源进行优化配置研究,已成为水资源规划与管理中的热点问题。文章运用多目标规划理论,建立了以经济、社会、财务等综合效益目标化最大的冯家山水库水量优化配置模型。通过确定模型各参数,调用Matlab优化工具箱中的函数进行编程求解,得到冯家山水库不同规划水平年(2015年、2020年)的水资源优化配置方案,为库区水资源规划与管理提供科学依据。 相似文献
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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。 相似文献
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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. 相似文献
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Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river. 相似文献
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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. 相似文献
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V. K. Konovalov O. V. Yashkin V. V. Ermakov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2008,42(2):105-109
A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed
in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash
and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers
of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional
components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect
dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system,
configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants
of dry ash utilization and the advantages of producing of size-separated particles are considered.
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Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008). 相似文献
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Peter B. Bayley 《河流研究与利用》1991,6(2):75-86
The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed. 相似文献