Many significant engineering and scientific problems involve optimization of some criteria over a combinatorial configuration space. The two methods most often used to solve these problems effectively-simulated annealing (SA) and genetic algorithms (GA)-do not easily lend themselves to massive parallel implementations. Simulated annealing is a naturally serial algorithm, while GA involves a selection process that requires global coordination. This paper introduces a new hybrid algorithm that inherits those aspects of GA that lend themselves to parallelization, and avoids serial bottle-necks of GA approaches by incorporating elements of SA to provide a completely parallel, easily scalable hybrid GA/SA method. This new method, called Genetic Simulated Annealing, does not require parallelization of any problem specific portions of a serial implementation-existing serial implementations can be incorporated as is. Results of a study on two difficult combinatorial optimization problems, a 100 city traveling salesperson problem and a 24 word, 12 bit error correcting code design problem, performed on a 16 K PE MasPar MP-1, indicate advantages over previous parallel GA and SA approaches. One of the key results is that the performance of the algorithm scales up linearly with the increase of processing elements, a feature not demonstrated by any previous parallel GA or SA approaches, which enables the new algorithm to utilize massive parallel architecture with maximum effectiveness. Additionally, the algorithm does not require careful choice of control parameters, a significant advantage over SA and GA.
展开▼
机译:许多重大的工程和科学问题涉及在组合配置空间上优化某些标准。有效地模拟退火(SA)和遗传算法(GA)的两种最常用于解决这些问题的方法,很难轻易地应用于大规模并行实现。模拟退火是一种自然的串行算法,而GA涉及需要全局协调的选择过程。本文介绍了一种新的混合算法,该算法继承了GA可以并行化的那些方面,并通过合并SA元素来提供完全并行,易于扩展的混合GA / SA方法,从而避免了GA方法的串行瓶颈。这种称为遗传模拟退火的新方法不需要并行化串行实现的任何特定问题部分,可以将现有的串行实现按原样合并。在16 K PE MasPar MP-1上进行的两个困难的组合优化问题,一个100个城市旅行销售员问题和一个24字,12位纠错码设计问题的研究结果表明,与以前的并行GA和SA方法相比,该方法具有优势。关键结果之一是该算法的性能随处理元素的增加而线性增加,这是任何以前的并行GA或SA方法都未展示的功能,这使新算法能够以最大的效率利用大规模并行体系结构。此外,该算法不需要仔细选择控制参数,这是相对于SA和GA的显着优势。
展开▼