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22.
D.E. Kvasov D. Menniti A. Pinnarelli Y.D. Sergeyev N. Sorrentino 《Electric Power Systems Research》2008
In this paper, the problem of global tuning of fuzzy power-system stabilizers (FPSSs) present in a multi-machine power system in order to damp the power system oscillations is considered. In particular, it is formulated as a problem of global minimization of a multiextremal black-box function over a multidimensional hyperinterval. A global optimization technique, recently proposed, is used for solving the stated problem: the search hyperinterval is partitioned into smaller hyperintervals and the objective function is evaluated only at two vertices corresponding to the main diagonal of the generated hyperintervals, thus avoiding unnecessary ponderous simulations. Then, the performances of this technique are numerically compared with ones of a genetic algorithm (GA). 相似文献
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24.
A genetic algorithm for the optimisation of assembly sequences 总被引:6,自引:0,他引:6
This paper describes a Genetic Algorithm (GA) designed to optimise the Assembly Sequence Planning Problem (ASPP), an extremely diverse, large scale and highly constrained combinatorial problem. The modelling of the ASPP problem, which has to be able to encode any industrial-size product with realistic constraints, and the GA have been designed to accommodate any type of assembly plan and component. A number of specific modelling issues necessary for understanding the manner in which the algorithm works and how it relates to real-life problems, are succinctly presented, as they have to be taken into account/adapted/solved prior to Solving and Optimising (S/O) the problem. The GA has a classical structure but modified genetic operators, to avoid the combinatorial explosion. It works only with feasible assembly sequences and has the ability to search the entire solution space of full-scale, unabridged problems of industrial size. A case study illustrates the application of the proposed GA for a 25-components product. 相似文献
25.
26.
Speed-up fractal image compression with a fuzzy classifier 总被引:4,自引:0,他引:4
This paper presents a fractal image compression scheme incorporated with a fuzzy classifier that is optimized by a genetic algorithm. The fractal image compression scheme requires to find matching range blocks to domain blocks from all the possible division of an image into subblocks. With suitable classification of the subblocks by a fuzzy classifier we can reduce the search time for this matching process so as to speedup the encoding process in the scheme. Implementation results show that by introducing three image classes and using fuzzy classifier optimized by a genetic algorithm the encoding process can be speedup by about 40% of an unclassified encoding system. 相似文献
27.
T. Xiaodong R. Xueyu W. Yuexian 《The International Journal of Advanced Manufacturing Technology》2002,20(4):303-312
Mesh simplification is one of the most important links in the context of reverse engineering. It is also an important consideration
in computer graphics. This paper presents a novel and original method of triangular mesh reduction. A new concept of super-face
is defined. In order to construct a super-face, a way to calculate the scattered point curvature is discussed. The growth
of a seed point and the combination of different regions are also necessary for the construction of a super-face. When the
hole left by the deletion of super-face is retriangulated a genetic algorithm is used that has been modified for our specific
problem. Then the different weights to balance the optimisation of the new triangular mesh can be adjusted. 相似文献
28.
The problem of packing circles into a domain of prescribed topology is considered. The circles need not have equal radii. The Collins-Stephenson algorithm computes such a circle packing. This algorithm is parallelized in two different ways and its performance is reported for a triangular, planar domain test case. The implementation uses the highly parallel graphics processing unit (GPU) on commodity hardware. The speedups so achieved are discussed based on a number of experiments. 相似文献
29.
无线传感网络是当前无线网络研究的热点领域,分簇路由协议作为降低网络能耗、提高网络生存时间的核心技术而备受关注。在深入分析已有算法存在诸多不足的基础上,本文提出了一种基于减聚类优化的分簇路由算法。本文首先建立一阶能耗模型,确定网络最优簇首数量;然后建立减聚类优化数学模型,确定可供选择的分簇方案;最后以最小化最大簇内距离方差作为评价指标,确定最优的分簇结果。仿真结果表明:相比经典的LEACH分簇路由协议,该算法划分的网络能够有效地降低网络能耗、提高网络生存时间,弥补已有算法的不足之处。 相似文献
30.
郭乐新 《电脑与微电子技术》2012,(2):3-5,18
旅行商问题TSP是一类典型的NP完全问题.围绕着这个问题有各种不同的求解方法,已有的算法例如动态规划法、分支限界法、回溯法等,这些精确式方法都是指数级的,根本无法解决目前的实际问题.贪心法是近似方法.无法达到比较满意的近似比。常用的遗传算法也是求解这类问题的常用方法之一。由于该问题的解是一种特殊的序列.所以遗传算法在求解该问题时的性能也并不理想。模拟退火算法具有描述简单、使用灵活、运用广泛、运行效率高和较少受到初始条件约束等优点.是解决旅行商问题的一种很好的算法。 相似文献