An outerplanar graph is a planar graph that can be imbedded in the plane in such a way that all vertices lie on the exterior face. An outerplanar graph is maximal if no edge can be added to the graph without violating...
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An outerplanar graph is a planar graph that can be imbedded in the plane in such a way that all vertices lie on the exterior face. An outerplanar graph is maximal if no edge can be added to the graph without violating the outer-planarity. In this paper, an optimal parallel algorithm is proposed on the EREW PRAM for testing isomorphism of two maximal outerplanar graphs. The proposed algorithm takes O(log n) time using O(n) work. Besides being optimal, it is very simple. Moreover, it can be implemented optimally on the CRCW PRAM in O(1) time. (C) 2002 Elsevier Science (USA).
This paper introduces a new parallel algorithm for computing an N( = n!)-point Lagrange interpolation on an n-star (n > 2). The proposed algorithm exploits several communication techniques on stars in a novel way, ...
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This paper introduces a new parallel algorithm for computing an N( = n!)-point Lagrange interpolation on an n-star (n > 2). The proposed algorithm exploits several communication techniques on stars in a novel way, which can be adapted for computing similar functions. It is optimal and consists of three phases: initialization, main, and final. While there is no computation in the initialization phase, the main phase is composed of n!/2 steps, each consisting of four multiplications, four subtractions, and one communication operation and an additional step including one division and one multiplication. The final phase is carried out in (n-1) subphases each with O(log n) steps where each step takes three communications and one addition. Results from a cost-performance comparative analysis reveal that for practical network sizes the new algorithm on the star exhibits superior performance over those proposed for common interconnection networks. (C) 2002 Elsevier Science (USA).
The external selection problem is to select the record with the K-th smallest key from the given N records that are distributed and stored evenly on the D disks for the parallel machine with D processors. Each process...
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ISBN:
(纸本)0769515126
The external selection problem is to select the record with the K-th smallest key from the given N records that are distributed and stored evenly on the D disks for the parallel machine with D processors. Each processor has its own primary memory of size M records and one disk, where N/D> M. The processors are connected with a root D X rootD Mesh architecture. Based on a two-stage approach, this paper presents an efficient parallel external selection algorithm for the distributed-memory parallel systems. First, all the processors execute local external sorting in parallel, each processor sorts the N/D records on its own disk. Next, they execute parallel external selection from the D sorted sub files on the D disks. This algorithm is asymptotically optimal and has a small constant factor of time complexity.
In the presented work the authors included the comparison of the calculations of a parallel FDTD algorithm with the computations obtained with the use of the Quick Wave programme published by QWED. The authors worked ...
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ISBN:
(纸本)0769517315
In the presented work the authors included the comparison of the calculations of a parallel FDTD algorithm with the computations obtained with the use of the Quick Wave programme published by QWED. The authors worked out a parallel implementation of the standard FDTD algorithm which is based on MPI communication library. The parallel algorithm was examined in a heterogeneous PC cluster.
In the article the authors describe an idea of parallel implementation of a conjugate gradient method in a heterogeneous PC cluster and a supercomputer Hitachi SR-2201. The new version of algorithm implementation diff...
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ISBN:
(纸本)0769517315
In the article the authors describe an idea of parallel implementation of a conjugate gradient method in a heterogeneous PC cluster and a supercomputer Hitachi SR-2201. The new version of algorithm implementation differs from the one applied earlier[1], because it uses a special method for storing sparse coefficient matrices: only non-zero elements are stored and taken into account during computations, so that the sparsity of the coefficient matrix is taken full advantage of. The article includes a comparison of the two versions. A speedup of the parallel algorithm has been examined for three different cases of coefficient matrices resulting in solving different physical problems. The authors have also investigated a preconditioning method, which uses the inversed diagonal of the coefficient matrix, as a preconditioning matrix.
Investigations of the parallel computing of the non-ideal 3-D space detonation wave propagation are presented in this paper on the hi-performance computer based on CC-NUMA architecture. Upon analyzing and testing the ...
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ISBN:
(纸本)0769515126
Investigations of the parallel computing of the non-ideal 3-D space detonation wave propagation are presented in this paper on the hi-performance computer based on CC-NUMA architecture. Upon analyzing and testing the previous serial program, the computation of curvature, the first-order and the second-order difference were determined to be the main objects of parallelization. Some processing techniques were applied to convert the serial program into parallel program, such as the strategy of "Divide and Conquer", the balance of the loading distribution. Numerical simulation computation of the parallel program results in a great increase of computing speed of the non-ideal 3-D space detonation wave propagation.
The use of page-level join index in parallel join optimization requires a proper sequence for accessing data pages in the form of join components. The current approach to this method involves a strategy that retrieves...
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ISBN:
(纸本)0769515797
The use of page-level join index in parallel join optimization requires a proper sequence for accessing data pages in the form of join components. The current approach to this method involves a strategy that retrieves first those components with a high number of page joins so as to keep all processors busy early in the join execution. However, problems regarding conflicts with other valid reading strategies and the choice of an appropriate component whenever several of them satisfy the selection criterion have not been specifically addressed. We call such conflicts as the Join Component Selection (JCS) problem. To resolve this problem, this paper proposes appropriate component retrieving strategies that will further optimize the parallel join execution. Simulation results demonstrate an improvement over the existing one.
This paper first presents two implementations of parallel Gaussian elimination using MPI, one uses cyclic data mapping and pipelined point-to-point communication, the other one uses blocked data mapping and MPI collec...
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ISBN:
(纸本)0769517315
This paper first presents two implementations of parallel Gaussian elimination using MPI, one uses cyclic data mapping and pipelined point-to-point communication, the other one uses blocked data mapping and MPI collective communication. Then, theoretical performance analysis for the two implementations is given, and the impacts of different data distribution and communication methods are compared.
In the following paper a two-dimensional parallel algorithm FDTD is presented. It uses a decomposition of a space domain into sub-areas. The shapes of the dielectrics are approximated by the groups of rectangles, desc...
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ISBN:
(纸本)0769517315
In the following paper a two-dimensional parallel algorithm FDTD is presented. It uses a decomposition of a space domain into sub-areas. The shapes of the dielectrics are approximated by the groups of rectangles, described by coordinates. In addition, the parallel algorithm was equipped in the Specific Absorption Rate and Temperature Increases calculation modules. The paper also contains the results of the efficiency research into two types of the connection topology of the computation nodes. The computations were made on a homogeneous cluster of personal computers.
Summary form only given. We show a parallel algorithm using a rectangle greedy matching technique which requires a linear number of processors and O(log(M)log(n)) time on the PRAM EREW model. The algorithm is suitable...
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