摘要:

In this paper we present a connectionist searching technique - the Stochastic Diffusion Search (SDS), capable of rapidly locating a specified pattern in a noisy search space. In operation SDS finds the position of the pre-specified pattern or if it does not exist - its best instantiation in the search space. This is achieved via parallel exploration of the whole search space by an ensemble of agents searching in a competitive cooperative manner. We prove mathematically the convergence of stochastic diffusion search. SDS converges to a statistical equilibrium when it locates the best instantiation of the object in the search space. Experiments presented in this paper indicate the high robustness of SDS and show good scalability with problem size. The convergence characteristic of SDS makes it a fully adaptive algorithm and suggests applications in dynamically changing environments.

ISSN:1063-7192    

DOI:10.1080/10637199808947380

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

This paper reports the results of vectorizing and parallelizing the circuit simulator HSPICE on the Cray C90 supercomputer. The results show that significant speedup of circuit simulation is achievable when the transistor model evaluation and the Jacobian matrix update are vectorized and parallelized efficiently. A speedup of 40 times on 16 vector processors was achieved for MOSFET transistor model evaluation component. Furthermore, matrix update time was reduced by one order of magnitude and the solver time was reduced by a factor of 2 to 5 for the four circuits simulated. As a result, a total simulation speedup of about 12 times on 16 vector processors was achieved.

ISSN:1063-7192    

DOI:10.1080/10637199808947381

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Automatic Data partitioning is one of the most crucial issues in the parallelization of programs for distributed memory message passing parallel machines. Several aspects of this problem are known to be NP-compfete and other researchers have proposed heuristic based solutions to solve this problem. In this paper, we propose a novel approach based on genetic algorithm as a powerful alternative. Our algorithm is interesting not only because it applies a randomized search technique to solve this problem, but also because it is simple and efficient. Moreover, our algorithm can afford to look at large search spaces of possible partitioning schemes to quickly arrive at the right data partition. We present some of the results from our prototype implementation of our algorithm on the IBM SP2 cluster.

ISSN:1063-7192    

DOI:10.1080/10637199808947382

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

In this paper we present an algorithm for solving the distributed termination detection problem. In particular, a strategy based on message counting is used to detect the termination of a distributed computation consisting of a set of processes asynchronously communicating over communication links. The proposed algorithm does not require the FIFO property for the communication links. The assumptions regarding the connectivity of the processes are very simple. For the proposed algorithm we demonstrate the correctness, we evaluate the message and the bit complexity and we give a detailed description of a MPI implementation.

ISSN:1063-7192    

DOI:10.1080/10637199808947383

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor