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排序方式: 共有658条查询结果,搜索用时 46 毫秒
1.
演化神经网络算法   总被引:1,自引:0,他引:1  
演化算法的应用使神经网络的训练有了一个崭新的面貌,目标函数既不要求连续,也不要求可微,仅要求该问题可计算,而且它的搜索始终遍及整个解空间,因此容易得到全局最优解,应用这一思想,本文提出了一种新的演化神经网络算法-EPANN,并通过算法实例说明EPANN是可行的。  相似文献   
2.
P systems based multi-objective optimization algorithm   总被引:2,自引:0,他引:2  
Based on P systems, this paper proposes a new multi-objective optimization algorithm (PMOA). Similar to P systems, PMOA has a cell-like structure. The structure is dynamic and its membranes merge and divide at different stages. The key rule of a membrane is the communication rule which is derived from P systems. Mutation rules are important for the algorithm, which has different ranges of mutation in different membranes. The cooperation of the two rules contributes to the diversity of the population, the conquest of the muhimodality of objective function and the convergence of algorithm. Moreover, the unique structure divides the whole population into several sub populations, which decreases the computational complexity. Almost a dozen popular algorithms are compared using several test problems. Simulation results illustrate that the PMOA has the best performance. Its solutions are closer to the true Pareto-optimal front  相似文献   
3.
丁超  成晔  何苗 《清华大学学报》2007,12(4):459-465
Let G = (V, E) be a complete undirected graph with vertex set V, edge set E, and edge weights l(e) satisfying the triangle inequality. The vertex set V is partitioned into clusters V1, V2, …, Vk. The clustered traveling salesman problem (CTSP) seeks to compute the shortest Hamiltonian tour that visits all the verti- ces, in which the vertices of each cluster are visited consecutively. A two-level genetic algorithm (TLGA) was developed for the problem, which favors neither intra-cluster paths nor inter-cluster paths, thus realized inte- grated evolutionary optimization for both levels of the CTSP. Results show that the algorithm is more effec- tive than known algorithms. A large-scale traveling salesman problem (TSP) can be converted into a CTSP by clustering so that it can then be solved by the algorithm. Test results demonstrate that the clustering TLGA for large TSPs is more effective and efficient than the classical genetic algorithm.  相似文献   
4.
应急设计框架:卫星总体方案设计   总被引:2,自引:0,他引:2  
以卫星有效载荷总体方案变型设计为背景,探讨在人为或自然灾害的非正常情况下的应急设计方法.首先给出应急设计系统定义,然后给出实现应急设计基本依据:一是基于演化算法、Agent、人机结合和协同设计理论;二是仿蚁群社会应急行为.本系统的关键是,构造基干人与演化算法相结合的Agent(human—computer cooperation Agent,HC—Agent),进而基于混合P2P网络模型构成多HC—Agent的协同设计系统,以使该应急设计系统具有抗干扰、自适应、快速响应的设计能力.  相似文献   
5.
We introduce a new dynamical evolutionary algorithm(DEA) based on the theory of statistical mechanics and investigate the reconstruction problem for the nonlinear dynamical systems using observation data. The convergence of the algorithm is discussed. We make the numerical experiments and test our model using the two famous chaotic systems (mainly the Lorenz and Chen systems). The results show the relatively accurate reconstruction of these chaotic systems based on observational data can be obtained. Therefore we may conclude that there are broad prospects using our method to model the nonlinear dynamical systems.  相似文献   
6.
The paper proposes an on-line signature verification algorithm, through which test sample and template signatures can be optimizedly matched, based on evolutionary computation (EC). Firstly, the similarity of signature curve segment is defined, and shift and scale transforms are also introduced due to the randoness of on-line signature. Secondly, this paper puts forward signature verification matching algorithm after establishment of the mathematical model. Thirdly, the concrete realization of the algorithm based on EC is discussed as well. In addition, the influence of shift and scale on the matching result is fully considered in the algorithm. Finally, a computation example is given, and the matching results between the test sample curve and the template signature curve are analyzed in detail, The preliminary experiments reveal that the type of signature verification problem can be solved by EC.  相似文献   
7.
Investigation on Relationship between Cost and Software Reliability   总被引:1,自引:0,他引:1  
Based on the fact that the software development cost is an important factor to control the whole project, we discuss the relationship between the software development cost and software reliability according to the empirical data collected from the development process. By evolutionary modeling we get an empirical model of the relationship between cost and software reliability, and validate the estimate results with the empirical data.  相似文献   
8.
We use evolutionary computing to synthesize Boolean functions randomly. By using specific crossover and mutation operator in evolving process and modifying search space and fitness function, we get some high non-linearity functions which have other good cryptography characteristics such as autocorrelation etc. Comparing to other heuristic search techniques, evolutionary computing approach is more effective because of global search strategy and implicit parallelism.  相似文献   
9.
Based on the theories of EA (Evolutionary Algorithm) and EHW (Evolvable Hardware), we devise an EHW based software-hardware co designing platform ECDP, on which we provided standards for hardware system encoding and evolving operation designing, as well as circuit emulating tools. The major features of this system are: two layer-encoding of circuit structure, off-line evolving with software cmulation and the evolving of genetic program designing. With this system, we implemented the auto designing of sonic software-hardware systems, like the random number generator.  相似文献   
10.
We introduced the work on parallel problem solvers from physics and biology being developed by the research team at the State Key Laboratory of Software Engineering, Wuhan University. Results on parallel solvers include the following areas: Evolutionary algorithms based on imitating the evolution processes of nature for parallel problem solving, especially for parallel optimization and model-building; Asynchronous parallel algorithms based on domain decomposition which are inspired by physical analogies such as elastic relaxation process and annealing process, for scientific computations, especially for solving nonlinear mathematical physics problems. All these algorithms have the following common characteristics: inherent parallelism, self-adaptation and self-organization, because the basic ideas of these solvers are from imitating the natural evolutionary processes. Foundation item: Supported by the National Natural Science Foundation of China (No. 60133010, No. 70071042, No. 60073043) and National Laboratory for Parallel and Distributed Processing Biography: Li Yan (1974-), female, Ph. D candidate, research direction: evolutionary computation.  相似文献   
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