A new general framework for agent cooperation and coordination in solving distributed constraint satisfaction problems (DCSPs) is presented. The Asynchronous Partitioning Framework (APF) first partitions agents into groups of agents, based on some heuristic, prior to any search being conducted. During the partitioning one of the agents in each group is assigned the role of a group leader. Next,...

This paper proposes a new crossover method for parallel distributed genetic algorithms (PDGAs). PDGAs with multiple subpopulations provide better solutions than conventional GAs with a single population. The proposed method, including the hybridization crossover and the best combinatorial crossover, is designed to increase the performance of PDGAs. The proposed method, which provides high local...

Among the various approaches for parallel depthrst search (DFS), the stack-splitting schemes are most popular. However, as shown in this paper, dynamical stack-splitting is not suitable for massively parallel systems with several hundred processors. Initial work-load imbalances and work packets of dissimilar sizes cause a high communication overhead. We compare work-load balancing strategies of...

We describe our experience in developing Web Search Systems using Oracle’s SQL*TextRetrieval. In the prototype system we store on-line books in the HTML and the HTML documents of a web site, SQL*TextRetrieval is used to index full text and other structured data in the ’web space’ and to provide an efficient search engine for free-text search. The Web enables global access to and maximum informa...

this paper proposes a novel hybrid algorithm namely apso-bfo which combines merits of bacterial foraging optimization (bfo) algorithm and adaptive particle swarm optimization (apso) algorithm to determine the optimal pid parameters for control of nonlinear systems. to balance between exploration and exploitation, the proposed hybrid algorithm accomplishes global search over the whole search spa...

Modeling and analysis techniques are used to investigate the performance of a massively parallel version of DIRECT, a global search algorithm widely used in multidisciplinary design optimization applications. Several high-dimensional benchmark functions and real world problems are used to test the design effectiveness under various problem structures. In this second part of a two-part work, the...

Modeling and analysis techniques are used to investigate the performance of a massively parallel version of DIRECT, a global search algorithm widely used in multidisciplinary design optimization applications. Several high-dimensional benchmark functions and real world problems are used to test the design effectiveness under various problem structures. Theoretical and experimental results are co...

The present study shows that search for a conjunction of color and orientation can be performed in parallel when the target is embedded in a spatially contiguous subset of nontarget elements. When the colored subset is spatially scattered among other items in the display, serial search through the colored subset is necessary. The results provide evidence for the notion of sequential parallel pr...