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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
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从ZnO电阻的非线性特性出发,对采用ZnO作为灭磁电阻时阀片的均流/均能进行理论论述,指出阀片均能性能的好坏主要依赖于阀片自身的特性;分析比较了ZnO阀片的不同选择方法对均流/均能的影响,指出阀片的均流/均能很大程度上取决于可供选择的阀片的库存量.该研究为发电机励磁系统的安全稳定运行提供了有力的保证. 相似文献
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以贵州尖山营滑坡为工程背景,通过对深度学习的总结与分析,建立多层感知器模型以对该滑坡危险区范围进行非线性预测研究。通过对深度神经网络算法的优化,构建64-128-32-1四层多层感知器模型,并以滑坡最大高差、滑坡体积、滑源区坡度、坡脚坡度、地层倾角作为输入量,以滑坡最大水平运动距离作为输出量对该模型进行训练,实现影响因素与运动距离的非线性映射。根据对贵州省尖山营滑坡调查和研究,尖山营滑坡区域面积约648 700 m2,体积约1 200万 m3,属于特大型滑坡。依据最优模型对该滑坡进行滑距预测,滑坡平面直线距离1 769 m区域内为危险区域。 相似文献
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运用混沌理论对我国股票市场进行了实证研究 ,结果显示我国股票市场是一个低自由度的混沌系统 ,具有自相似的非线性结构 ,并且这种非线性结构可以用 GARCH( 1 ,1 )模型来拟合。 相似文献
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刘学杰 《石家庄经济学院学报》2003,26(3):314-317
马克思在《资本论》中提出了在未来社会“重新建立个人所有制”的设想,成为马克思留给后人的历史之迷。笔者根据马克思的人的全面发展理论并通过分析其早年的“劳动异化理论”认为:“个人所有制”是消灭私有制、实现公有制的真实体现。“重新建立个人所有制”是指社会财富由私有制条件下的剥削被剥削的“现状”向“应当”由劳动者自己享有的现实“回归”,是实现人的全面发展的经济保证。 相似文献
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Noisy chaotic dynamics in commodity markets 总被引:2,自引:1,他引:2
Catherine?Kyrtsou Walter C.?LabysEmail author Michel?Terraza 《Empirical Economics》2004,29(3):489-502
The nonlinear testing and modeling of economic and financial time series has increased substantially in recent years, enabling us to better understand market and price behavior, risk and the formation of expectations. Such tests have also been applied to commodity market behavior, providing evidence of heteroskedasticity, chaos, long memory, cyclicity, etc. The present evaluation of futures price behavior confirms that the resulting price movements can be random, suggesting noisy chaotic behavior. Prices could thus follow a mean process that is dynamic chaotic, coupled with a variance that follows a GARCH process. Our conclusion is that models of this type could be constructed to assist in forecasting prices in the short run but not over long run time periods.First version received: June 2001/Final version received: March 2003 相似文献
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Tae Kyung Sung David V. Gibson Byung-Su Kang 《Technological Forecasting and Social Change》2003,70(5):449-466
This article explores the characteristics of venture business and entrepreneurs in Korea to (1) identify technology transfer activities, (2) analyze the differences between technology transfer in linear and nonlinear venture businesses, and (3) guide more effective venture business policy and strategy. This empirical assessment reveals that entrepreneurs have insightful evaluations about their resources and capacities as well as expectations with regard to functions and features of science parks and incubators. Respondents from “linear model”-based start-ups tend to be older and have higher education, employ more basic research and development (R&D) and have more R&D-oriented careers, and have more varied work experience than “nonlinear”-based start-ups. The functions and features of science parks and incubators were generally not considered a critical influence on start-ups nor on the growth of venture businesses. Accordingly, alternative venture-nurturing strategies are discussed as being key to accelerate venture businesses growth. 相似文献