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1.
为了充分利用现今普及的多核配置计算机,提高大规模梯级水库群优化调度问题的求解效率,提出了梯级水库群优化调度的粗粒度并行自适应混合粒子群算法。该方法以自适应混合粒子群算法为求解基础,采用粗粒度并行设计模式,利用Fork/Join多核并行框架的分治策略,将其初始种群递归划分为多个子种群,平均分配到不同的内核逻辑线程中实现并行计算,并在各子种群优化结束后,合并优化结果集从而输出全局最优解。以澜沧江下游梯级水库群发电优化调度为例,利用该方法进行计算。结果表明,该方法能充分发挥多核配置的计算性能,在4核环境下最大加速比达到3.97,缩短计算耗时1 787.2 s,计算效率显著提高,为我国不断扩张的大规模梯级水库群优化调度提供了一种切实可行的高效求解途径。  相似文献   

2.
为了充分利用当今流行的多核配置资源提高梯级水库群优化调度的精细化管理水平,提出梯级水库群优化调度并行自适应混沌整体退火遗传算法。该方法利用Fork/Join多核并行框架的分治法将自适应混沌整体退火遗传算法的初始种群递归分解为多个规模更小的子种群,并平均分配到不同的内核中同时进行优化计算,实现算法的粗粒度并行求解。红水河梯级水库群发电优化调度实例结果表明,该方法比串行计算能大幅度缩减优化求解时间,提高计算效率,而且其并行化设计模式可为其他群体智能算法的并行化提供参考和借鉴。  相似文献   

3.
梯级水电站群并行多目标优化调度方法   总被引:1,自引:0,他引:1  
为保障梯级水电站群多目标优化调度问题的计算效率和求解精度,提出了基于Fork/Join多核并行框架的并行多目标遗传算法。该方法以多目标遗传算法为基础,引入多种群异步进化策略保证种群间个体多样性;采用迁移机制保障子种群的信息有机互馈,提升算法收敛性和解集多样性;利用并行技术实现子种群在各内核的同步求解,提高计算效率。针对问题特点,耦合个体实数串联编码方法、混沌初始化种群策略和约束Pareto占优机制等,进一步提升方法寻优性能。澜沧江流域梯级水电站群多目标优化调度结果表明,所提方法可充分利用多核资源,提升模型计算效率与求解精度,并能获得分布均匀、合理可行的调度方案集,为水电系统多目标高效决策提供科学依据。  相似文献   

4.
为了满足大规模梯级水库群优化调度精细化管理需求,解决决策计算耗时长及求解效率低等困难,提出了基于Fork/Join多核并行框架的梯级水库群优化调度并行求解方法,并以离散微分动态规划方法并行化为例,给出了梯级水库群优化调度方法在Fork/Join框架下的并行化实现方式。红水河大规模梯级水库群长期发电优化调度测试结果表明,并行计算能够充分发挥多核处理器的加速性能,有效缩短计算耗时,提高求解效率;选择合理的Fork/Join框架规模控制阈值是充分发挥并行优势的关键因素。  相似文献   

5.
库群长期优化调度的多核并行禁忌遗传算法   总被引:3,自引:2,他引:1  
刘本希  廖胜利  程春田  武新宇 《水利学报》2012,43(11):1279-1286
针对库群长期优化调度求解效率低下、实用性差等问题,提出了多核并行禁忌遗传算法。该算法利用遗传算法适应性强、运算简单等优势,采用多种群计算方式保持种群多样性,以提高算法的全局收敛能力;在子种群进化过程中应用单向环迁移拓扑模型进行信息交换,以增强算法收敛能力;结合子种群间求解独立的特点,引入多核并行计算策略,并使用禁忌搜索思想避免重复计算适应值,提高了算法的求解效率。红水河流域10座水电站的计算结果表明,该算法可以显著缩短计算时间,获得良好的调度方案,是求解库群长期优化调度的一种有效方法。  相似文献   

6.
基于模拟-优化模式的供水水库群联合调度规则研究   总被引:4,自引:3,他引:1  
提出了基于模拟-优化模式的混联供水水库群联合优化调度规则求解框架。首先,通过构建虚拟聚合水库,编制联合调度图,以做出水库群对各用水户的供水方案;其次,通过优化成员水库供水任务分配因子,并结合供水水库群常规调度规则,实现共同供水任务在水库间的优化分配。采用改进粒子群算法 (NSPSO) 对观音阁-葠窝-汤河水库群联合供水调度模型决策变量 (联合调度图调度线位置和成员水库供水任务分配因子) 进行多目标优化,分析联合供水调度过程中目标之间的竞争关系,检验联合调度规则的合理性与有效性以及NSPSO算法的优化效率。  相似文献   

7.
梯级水库群防洪优化调度问题规模庞大、结构复杂,涉及大量的决策变量和复杂的约束条件,各水库、各时段之间的水位、流量存在复杂的耦合关系,呈现出高维度、非线性、强约束特性,传统的优化方法难以直接求解或者计算效率低,存在早熟收敛问题。研究工作试图将量子粒子群算法(QPSO)引入到水库群防洪优化调度问题中,为了提高算法的全局搜索能力和收敛性能,对标准QPSO做了改进,包括利用混沌思想初始化种群、自适应激活机制和精英粒子混沌局部搜索策略3个方面,并引入多核并行计算技术以降低计算时间,提出了并行混沌量子粒子群算法(PCQPSO),函数测试证明了PCQPSO的可行性、稳定性和高效性。将PCQPSO应用到水库群防洪优化调度问题中,与POA、QPSO进行对比分析,结果表明PCQPSO收敛效率快、求解精度高,为解决梯级水库群防洪优化调度问题提供了一种有效的新思路。  相似文献   

8.
基于模拟-优化模式的供水水库群联合调度规则研究   总被引:1,自引:0,他引:1  
提出了基于模拟-优化模式的混联供水水库群联合优化调度规则求解框架。首先,通过构建虚拟聚合水库,编制联合调度图,以做出水库群对各用水户的供水方案;其次,通过优化成员水库供水任务分配因子,并结合供水水库群常规调度规则,实现共同供水任务在水库间的优化分配。采用NSPSO算法对观音阁-葠窝-汤河水库群联合供水调度模型决策变量(联合调度图调度线位置和成员水库供水任务分配因子)进行多目标优化,分析联合供水调度过程中目标之间的竞争关系,检验联合调度规则的合理性与有效性以及NSPSO算法的优化效率。  相似文献   

9.
系统介绍了梯级水库群联合调度模型求解的常规优化方法和智能优化方法,其中常规优化方法包括动态规划法及其改进方法和大系统分解协调等方法,智能优化方法包括粒子群优化算法、遗传算法、差分进化算法等。在评述各种方法的基础上,给出了大规模水库群联合优化调度需要解决的问题:1模型系统求解的稳定性和求解效率的平衡问题;2考虑生态环境的多目标优化调度模式;3水库群优化调度模型描述方法;4优化模型输入和输出的不确定性问题;5机组高水头多振动区运行问题。同时,指出了智能优化算法的发展方向:1数学理论基础研究;2参数对算法结果的影响分析;3各种优化算法的改进与融合;4求解算法的并行计算和云计算技术。  相似文献   

10.
针对长江上游控制性水库群联合调度问题,建立了大规模混联水库群联合优化调度模型,并提出离散微分动态规划(DDDP)和逐步优化算法(POA)相结合的混合方法,实现大规模混联梯级水库群联合优化调度问题的高效求解。在此基础上,结合流域长系列历史径流资料,进行了长江上游控制性梯级水库群调度模拟,分析了联合调度的发电效益;并在此基础上,结合相关研究成果,探究并分析了梯级水库群建成投运后,联合调度对流域水资源的影响。成果表明,梯级水库群的建成及联合调蓄对于长江中下游枯水期的流量补偿效益十分明显,供水、航运以及压咸补淡等综合效益十分显著。  相似文献   

11.
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   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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   

16.
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. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).  相似文献   

17.
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   

18.
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。  相似文献   

19.
岩石动态拉伸断裂特性的实验研究   总被引:1,自引:0,他引:1  
采用新近发展起来的拉伸式Hopkinson冲击装置(SHTB),对岩石切口圆柱断裂试样进行了动态拉伸断裂特性的实验研究。同时,利用MTS试验机进行了岩石的静态拉伸断裂实验,成功地获得了岩石试样的断裂韧度及断裂能随加载率而变化的实验结果。对静态和动态破坏后的试样断口进行的扫描电镜观察进一步表明,试样断口形貌的复杂程度与其断裂耗能有着十分密切的联系。  相似文献   

20.
River regulation in the headwaters and middle reaches of the Gunnison River, Colorado, significantly altered distributions and abundances of Trichoptera fauna. Twenty-five species were collected from mainstream samples, with the greatest species richness occurring at an unregulated, rhithron segment above the central reach dams. At sites immediately below the three hypolimnial-release dams and a reregulation dam, species richness was reduced 35–90 per cent and abundance > 95 per cent. Net-spinning caddisflies were the dominant trichopterans at unregulated sites; Arctopsyche grandis in the upper reaches (218 organisms, 586 mg dry mass m?2) and Hydropsyche cockerelli, H. occidentalis and Cheumatopsyche pettiti in the lower river (9041 total organisms, 6621 mg m?2), downstream from the last dam. The observed distributional pattern of low trichopteran densities in dam tailwaters and high hydropsychid densities at sites 60–80 km below the central reach dams is a classic expression of continuum resets and adjustments in response to stream regulation as predicted by the Serial Discontinuity Concept.  相似文献   

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