With an aim to the fact that the K-means clustering algorithm usually ends in local optimization and is hard to harvest global optimization, a new web clustering method is presented based on the chaotic social evoluti...With an aim to the fact that the K-means clustering algorithm usually ends in local optimization and is hard to harvest global optimization, a new web clustering method is presented based on the chaotic social evolutionary programming （CSEP） algorithm. This method brings up the manner of that a cognitive agent inherits a paradigm in clustering to enable the cognitive agent to acquire a chaotic mutation operator in the betrayal. As proven in the experiment, this method can not only effectively increase web clustering efficiency, but it can also practically improve the precision of web clustering.展开更多
Co-ordination of directional over current relays(DOCR) requires the selection and setting of relays so as to sequentially isolate only that portion of the power system where an abnormality has occurred.The problem of ...Co-ordination of directional over current relays(DOCR) requires the selection and setting of relays so as to sequentially isolate only that portion of the power system where an abnormality has occurred.The problem of coordinating protective relays in electrical power systems consists of selecting suitable settings such that their fundamental protective function is met,given operational requirements of sensitivity,selectivity,reliability and speed.Directional over current relays are best suited for protection of an interconnected sub-station transmission system.One of the major problems associated with this type of protection is the difficulty in coordinating relays.To insure proper coordination,all the main/back up relay pairs must be determined.This paper presents an effective algorithm to determine the minimum number of break points and main/back up relay pairs using relative sequence matrix(RSM).A novel optimization technique based on evolutionary programming was developed using these main/back up relay pairs for directional over current relay coordination in multi-loop networks.Since the problem has multi-optimum points,conventional mathematics based optimization techniques may sometimes fail.Hence evolutionary programming(EP) was used,as it is a stochastic multi-point search optimization algorithm capable of escaping from the local optimum problem,giving a better chance of reaching a global optimum.The method developed was tested on an existing 6 bus,7 line system and better results were obtained than with conventional methods.展开更多
为提高传统GEP算法的全局搜索能力,提出一种基于模糊控制的多细胞基因表达式编程算法(multicellular GEP algorithm based on fuzzy control,MGEP-FC)。通过构建模糊隶属函数,对算法的交叉率、变异率和实数集变异率的大小进行描述,根据...为提高传统GEP算法的全局搜索能力,提出一种基于模糊控制的多细胞基因表达式编程算法(multicellular GEP algorithm based on fuzzy control,MGEP-FC)。通过构建模糊隶属函数,对算法的交叉率、变异率和实数集变异率的大小进行描述,根据种群中个体适应度值的集中和分散程度,动态调整遗传操作的交叉率、变异率和实数集变异率。为使种群的多样性在迭代过程中得到延续,设计一种遗传操作方案,将产生的新个体与父代种群结合构建临时种群,临时种群和子代种群的多样性均得到优化。12个Benchmark的函数寻优实验结果表明,该算法在稳定性、全局收敛能力和寻优速度等方面都得到了显著提升。展开更多
针对遗传规划算法容易陷入局部最优解与局部搜索过慢的问题,提出一种基于语义聚类的遗传规划算法(genetic programming algorithm based on semantic clustering,SCGP),比较不同聚类算法对SCGP表现的影响。同时提出一种基于子种群规模...针对遗传规划算法容易陷入局部最优解与局部搜索过慢的问题,提出一种基于语义聚类的遗传规划算法(genetic programming algorithm based on semantic clustering,SCGP),比较不同聚类算法对SCGP表现的影响。同时提出一种基于子种群规模的自适应适应度函数,提高局部搜索能力。在多个基准问题上对比标准遗传规划、几何语义遗传规划、K均值聚类遗传规划与SCGP,实验结果表明,SCGP算法在拟合能力和泛化能力上都有较大改善。在诸多聚类方法中,层次聚类嵌入的SCGP算法在基准问题上的泛化能力最优,与标准遗传规划、几何语义遗传规划、K均值聚类遗传规划相比,分别提高了32.36%、61.29%、20.53%。展开更多
文摘With an aim to the fact that the K-means clustering algorithm usually ends in local optimization and is hard to harvest global optimization, a new web clustering method is presented based on the chaotic social evolutionary programming （CSEP） algorithm. This method brings up the manner of that a cognitive agent inherits a paradigm in clustering to enable the cognitive agent to acquire a chaotic mutation operator in the betrayal. As proven in the experiment, this method can not only effectively increase web clustering efficiency, but it can also practically improve the precision of web clustering.
文摘Co-ordination of directional over current relays(DOCR) requires the selection and setting of relays so as to sequentially isolate only that portion of the power system where an abnormality has occurred.The problem of coordinating protective relays in electrical power systems consists of selecting suitable settings such that their fundamental protective function is met,given operational requirements of sensitivity,selectivity,reliability and speed.Directional over current relays are best suited for protection of an interconnected sub-station transmission system.One of the major problems associated with this type of protection is the difficulty in coordinating relays.To insure proper coordination,all the main/back up relay pairs must be determined.This paper presents an effective algorithm to determine the minimum number of break points and main/back up relay pairs using relative sequence matrix(RSM).A novel optimization technique based on evolutionary programming was developed using these main/back up relay pairs for directional over current relay coordination in multi-loop networks.Since the problem has multi-optimum points,conventional mathematics based optimization techniques may sometimes fail.Hence evolutionary programming(EP) was used,as it is a stochastic multi-point search optimization algorithm capable of escaping from the local optimum problem,giving a better chance of reaching a global optimum.The method developed was tested on an existing 6 bus,7 line system and better results were obtained than with conventional methods.
基金国家重点基础研究发展规划(973)(the National Grand Fundamental Research 973 Program of China under Grant No.2004CB318103)国家自然科学基金(the National Natural Science Foundation of China under Grant No.60133010)江西省研究生创新基金项目(No YC07A073)
文摘为提高传统GEP算法的全局搜索能力,提出一种基于模糊控制的多细胞基因表达式编程算法(multicellular GEP algorithm based on fuzzy control,MGEP-FC)。通过构建模糊隶属函数,对算法的交叉率、变异率和实数集变异率的大小进行描述,根据种群中个体适应度值的集中和分散程度,动态调整遗传操作的交叉率、变异率和实数集变异率。为使种群的多样性在迭代过程中得到延续,设计一种遗传操作方案,将产生的新个体与父代种群结合构建临时种群,临时种群和子代种群的多样性均得到优化。12个Benchmark的函数寻优实验结果表明,该算法在稳定性、全局收敛能力和寻优速度等方面都得到了显著提升。
文摘针对遗传规划算法容易陷入局部最优解与局部搜索过慢的问题,提出一种基于语义聚类的遗传规划算法(genetic programming algorithm based on semantic clustering,SCGP),比较不同聚类算法对SCGP表现的影响。同时提出一种基于子种群规模的自适应适应度函数,提高局部搜索能力。在多个基准问题上对比标准遗传规划、几何语义遗传规划、K均值聚类遗传规划与SCGP,实验结果表明,SCGP算法在拟合能力和泛化能力上都有较大改善。在诸多聚类方法中,层次聚类嵌入的SCGP算法在基准问题上的泛化能力最优,与标准遗传规划、几何语义遗传规划、K均值聚类遗传规划相比,分别提高了32.36%、61.29%、20.53%。
