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将差分-遗传混合算法用于分析直线隔水边界条件下的抽水试验数据,求解含水层参数。在易陷入早熟的遗传算法中,加入搜索能力强、受控参数少的差分进化算法,构成差分-遗传混合算法。该混合算法具有确定性运算和随机性搜索的优点,能够较好地平衡全局搜索和局部搜索。试验结果表明,差分-遗传混合算法能够有效地应用于分析抽水试验数据,识别含水层参数,与其他方法相比较,具有对初值的依赖性小、收敛性好和计算结果精度高等优点。 相似文献
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基于遗传神经网络的城市用水量预测研究 总被引:6,自引:0,他引:6
乔维德 《水科学与工程技术》2007,(3):1-3
介绍了BP(误差反向传播算法)和GA(遗传算法)及GA-BP 3种神经网络,并以此分别对城市用水量进行预测.实验结果表明,基于GA-BP算法的神经网络方法应用于城市用水量的预测问题,能采用遗传学习算法优化BP神经网络模型的初始权重,即先利用遗传学习算法进行全局训练,再用BP算法进行精确训练,使网络收敛速度加快和避免局部极小.GA-BP神经网络在收敛速度和预测精度等方面均优于BP和GA网络,从而为未来短期城市用水量负荷的准确预测提供了新的思路与方法. 相似文献
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介绍了用遗传和模拟退火组合算法来制定火力发电机组检修计划的方法 ,该算法以生产费用和检修费用之 和最小为优化目标。文中给出了一种用位串对检修计划 进行编码和解码的有效方法,并考虑了检修中可能 出现的约束条件。算例说明了该算法的可行性。 相似文献
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基于遗传学习算法和BP算法的神经网络在矿坑涌水量计算中的应用 总被引:12,自引:0,他引:12
本文采用遗传学习算法和误差反向传播算法(BP)相结合的混合算法来训练前馈人工神经网络(BPN),即先用遗传学习算法进行全局训练,再用BP算法进行精确训练,使网络收敛速度加快和避免局部极小。作为实例,本文将该方法运用于多维时序问题。根据山东省黑旺铁矿的矿坑充水条件建立了一个网络,以矿坑充水的各种控制因素相关资料作为样本,对网络进行训练并用训练好的网络预测矿坑涌水量。网络的训练速度及预测结果表明,该算法收敛速度较快,预测精度很高,为矿坑涌水量预报提供了一种新思路和新方法。 相似文献
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将小生境思想与遗传模拟退火算法相结合,应用于岩质边坡滑动面的搜索中。在实现了边坡结构面模拟的基础上,小生境与遗传模拟退火耦合算法可以顺利搜索出边坡由结构面与岩桥组合形成的潜在最危险滑动面。与其他智能优化搜索算法相比,该耦合算法具有收敛速度快、可找到搜索函数所有全局最优解、参数依赖性小等优点。工程应用实例表明该耦合算法在岩质边坡滑动面搜索中能取得令人满意的结果。 相似文献
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改进单亲遗传算法采用Kruskal算法和Dijkstra算法进行群体初始化代替随机群体初始化过程;采用赌轮盘选择和单亲换位算子作为主要遗传算子,取消选择率、换位率和单亲逆转算子,使算法结构更加简洁明了;增设单一化的最优群体,并自动更新最优群体适应度值的下限。研究表明,通过一系列改进,在同样能获得最优解的前提下,程序运行时间由70s缩短到5s,最大遗传代数由500代以上缩短到100代以下,改进单亲遗传算法(ISPGA)的性能提高显著。 相似文献
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巩琳琳 《陕西水利水电技术》2006,(1)
神经网络模型是近年来在需水预测方面应用较为广泛的一种方法,在陕西省的需水预测中根据实际情况采用遗传模拟退火算法对其进行优化,预测的结果和其他预测方法进行对比,证明该方法预测的结果较为合理,能够在类似的预测中加以推广应用。 相似文献
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提出一种基于单纯形-模拟退火算法的电力系统稳定器(PSS)参数优化方法。该方法以弱阻尼振荡模式构建目标函数,将单纯形法搜寻机理嵌入到模拟退火算法的基本步骤中,综合了模拟退火算法全局搜索能力强及单纯形算法局部收敛速度快的优点。四机典型系统上的特征根分析表明,该方法是一种有效的阻尼控制器优化方法,所得的参数对系统运行方式的变化具有良好的鲁棒性。 相似文献
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1.mTRonUCmNKirkpatricketal(1982)Pointedoutthatthereexistsananalogybetweencombinatorialoptimizationproblemandsolidannealingprocess-Inthelightofthisanalogy,Metropolisetalmedelledtheprocessthatsolidapprochesthermalequilibrium,andworkedouttheMetroPoliscriterionintheoptimizationprocess.Subsequently,theydevelopedakindofiter-ativeandcombinatorialoptimizationalgorithm,whichiscalledthesimulatedannealingalgo-rithm(SAA).SAAisasearchalgorithmbasedontheMonte-Carlomethedusedinstatisticalmechan-icsofan… 相似文献
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KANGLing WANGCheng JIANGTie-bing 《水动力学研究与进展(B辑)》2004,16(2):233-239
In this paper, a new approach, the Genetic Simulated Annealing (GSA), was proposed for optimizing the parameters in the Muskingum routing model. By integrating the simulated annealing method into the genetic algorithm, the hybrid method could avoid some troubles of traditional meth ods, such as arduous trial and error procedure, premature convergence in genetic algorithm and search blindness in simulated annealing. The principle and implementing procedure of this algorithm were described. Numerical experiments show that the GSA can adjust the optimization population, prevent premature convergence and seek the global optimal result. Applications to the Nanyunhe River and Qingjiang River show that the proposed approach is of higher forecast accuracy and practicability. 相似文献
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Joshua C. Steele Kurt Mahoney Omer Karovic Larry W. Mays 《Water Resources Management》2016,30(5):1605-1620
The design of urban stormwater systems and sanitary sewer systems consists of solving two problems: generating a layout of the system and the pipe design which includes the crown elevations, slopes and commercial pipe sizes. A heuristic model for determining the optimal (minimum cost) layout and pipe design of a storm sewer network is presented. The hierarchical procedure combines a sewer layout model formulated as a mixed-integer nonlinear programming (MINLP) problem which is solved using the General Algebraic Modeling System (GAMS) and a simulated annealing optimization procedure for the pipe design of a generated layout was developed in Excel. The GAMS and simulated annealing models are interfaced through linkage of Excel and GAMS. The pipe design model is based upon the simulated annealing method to optimize the crown elevations and diameter of pipe segments in a storm sewer network using layouts generated using GAMS. A sample scenario demonstrates that using these methods may allow for significant costs saving while simultaneously reducing the time typically required to design and compare multiple storm sewer networks. 相似文献
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介绍了基于MPI的并行编程环境;从传统的串行模拟退火算法出发,提出了并行模拟退火算法的并行思路和具体实现,给出了模拟退火算法并行实现的关键-并行随机数产生方法。最后通过一个拱坝优化设计的工程实例,说明并行模拟退火算法的正确性和高效性。 相似文献
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Optimal Operation of Reservoir Systems using Simulated Annealing 总被引:5,自引:0,他引:5
A stochastic search technique, simulated annealing (SA), is used to optimize the operation of multiple reservoirs. Seminal application of annealing technique in general to multi-period, multiple-reservoir systems, along with problem representation and selection of different parameter values used in the annealing algorithm for specific cases is discussed. The search technique is improved with the help of heuristic rules, problem-specific information and concepts from the field of evolutionary algorithms. The technique is tested for application to a benchmark problem of four-reservoir system previously solved using a linear programming formulation and its ability to replicate the global optimum solution is examined. The technique is also applied to a system of four hydropower generating reservoirs in Manitoba, Canada, to derive optimal operating rules. A limited version of this problem is solved using a mixed integer nonlinear programming and results are compared with those obtained using SA. A better objective function value is obtained using simulated annealing than the value from a mixed integer non-linear programming model developed for the same problem. Results obtained from these applications suggest that simulated annealing can be used for obtaining near-optimal solutions for multi-period reservoir operation problems that are computationally intractable. 相似文献