Based on the two-list algorithm and the parallel three-list algorithm, an improved parallel three-list algorithm for knapsack problem is proposed, in which the method of divide and conquer, and parallel merging withou...
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Based on the two-list algorithm and the parallel three-list algorithm, an improved parallel three-list algorithm for knapsack problem is proposed, in which the method of divide and conquer, and parallel merging without memory conflicts are adopted. To find a solution for the n-element knapsack problem, the proposed algorithm needs O(23n/8) time when O(23n/8) shared memory units and O(2n/4) processors are available. The comparisons between the proposed algorithm and 10 existing algorithms show that the improved parallel three-list algorithm is the first exclusive-read exclusive-write (EREW) parallel algorithm that can solve the knapsack instances in less than O(2n/2) time when the available hardware resource is smaller than O(2n/2), and hence is an improved result over the past researches.
Costas arrays,special permutation matrices,have been applied to many fields such as signal processing and ***,so far the basic problem—the counting problem remains *** all costas arrays of order n from n! permutation...
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Costas arrays,special permutation matrices,have been applied to many fields such as signal processing and ***,so far the basic problem—the counting problem remains *** all costas arrays of order n from n! permutation matrices has been of long standing *** an effective parallel search algorithm is *** algorithm adopts the classical master-slave *** processor is in charge of allocating search subspace to slave *** slave processor quests for costas arrays in assigned search *** processors do not communicate with each *** amount of communication between master and slave processors is *** the speedup of this algorithm approaches total number of used processors.
A new parallel algorithm is proposed for the knapsack problem where the method of divide and conquer is adopted. Based on an EREW-SIMD machine with shared memory, the proposed algorithm utilizes O(2 n/4 ) 1-ε ...
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A new parallel algorithm is proposed for the knapsack problem where the method of divide and conquer is adopted. Based on an EREW-SIMD machine with shared memory, the proposed algorithm utilizes O(2 n/4 ) 1-ε processors, 0≤ ε ≤1, and O(2 n/2 ) memory to find a solution for the n -element knapsack problem in time O(2 n/4 (2 n/4 ) ε) . The cost of the proposed parallel algorithm is O(2 n/2 ) , which is an optimal method for solving the knapsack problem without memory conflicts and an improved result over the past researches.
New parallel “ring” algorithm for solution of a spatially one dimensional initial-boundary-value problem (IBVP) for a parabolic equation using an explicit difference method in this article is suggested. The parallel...
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New parallel “ring” algorithm for solution of a spatially one dimensional initial-boundary-value problem (IBVP) for a parabolic equation using an explicit difference method in this article is suggested. The parallel algorithm has been verified by implementation on a workstation-cluster running under parallel virtual machine (PVM). A speed-up function is determined as a ratio of time needed for realization of the algorithm in sequential case to time in parallel. Theoretical estimates of the speed-up function show the significant speed-up of the parallel algorithm in comparison with the serial one.
This paper presents a new dynamic method of subpopulation in solving multi-modal search problems with evolutionary algorithms. The new method identify the modes found at each generation and equalises the subpopulation...
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This paper presents a new dynamic method of subpopulation in solving multi-modal search problems with evolutionary algorithms. The new method identify the modes found at each generation and equalises the subpopulation sizes assigned to each mode. Modes are identified sequentially starting with the highest fitness mode. Mode membership is determined by successive grouping of fitness dominated convex bounding neighbours, starting from the fittest individual. This new dynamic modal subpopulation approach is able to fmd a representative sample of optima for multi-modal landscape with infinite number of global and local optima with uneven heights and non-uniform distribution. The algorithm also facilitates parallel implementation.
The knapsack problem is very important in cryptosystem and in number *** paper proposes a new parallel algorithm for the knapsack problem where the method of divide and conquer is *** on an EREW-SIMD machine with shar...
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The knapsack problem is very important in cryptosystem and in number *** paper proposes a new parallel algorithm for the knapsack problem where the method of divide and conquer is *** on an EREW-SIMD machine with shared memory,the proposed algorithm utilizes O(2) processors,0≤ε≤1,and O(2) memory to find a solution for the n-element knapsack problem in time O(2(2)).Thus the cost of the proposed parallel algorithm is O(2),which is optimal,and an improved result over the past researches.
An algorithm-Master-Slave model for parallel volume rendering based on MPI is presented. According to the features of the ray-casting method, a task division strategy of image space is chosen for speeding up rendering...
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An algorithm-Master-Slave model for parallel volume rendering based on MPI is presented. According to the features of the ray-casting method, a task division strategy of image space is chosen for speeding up rendering, and a dynamic load balance is obtained via taskpools scheme. The algorithm introduced in this paper has been implemented, and experiment is done on the head and feet dataset of virtual Chinese female No.1 (VCH-F1), results show that this algorithm is provided with good parallel efficiency.
As a particle method, macro-scale pseudo-particle modeling (MaPPM) is an effective approach applied to micro-scale simulation of particle-fluid systems. In this paper, a parallel algorithm for macro-scale pseudo-parti...
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As a particle method, macro-scale pseudo-particle modeling (MaPPM) is an effective approach applied to micro-scale simulation of particle-fluid systems. In this paper, a parallel algorithm for macro-scale pseudo-particle modeling based on spatial decomposition (SD) is presented. The parallel implementation utilizes MPI as the programming environment. Due to movement of particles during simulation, the parallelization of MaPPM may suffer from load imbalance and attendant performance degradation. Recursive Coordinate Bisection (RCB) is adopted to partition the whole computational domain in a dynamic fashion to balance the workload in processors. The Shift scheme is modified to meet the communication requirement in the dynamic partition. The parallel approach was applied to simulation of bubble behavior in gas-solid fluidized beds with different system sizes to test its performance. The computations were conducted on cluster of workstations (COW). Experimental results show that the algorithm has a good scalability. With dynamic load balancing (DLB), the parallel efficiency can be improved by up to 8%. To sum up, it was a successful implementation for the parallelization of macro-scale pseudo-particle modeling. (c) 2004 Elsevier Ltd. All rights reserved.
We propose in this paper a quantum correction transport model for nanoscale double-gate metal-oxide-semiconductor field effect transistor (MOSFET) device simulation. Based on adaptive finite volume, parallel domain de...
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We propose in this paper a quantum correction transport model for nanoscale double-gate metal-oxide-semiconductor field effect transistor (MOSFET) device simulation. Based on adaptive finite volume, parallel domain decomposition, monotone iterative, and a posteriori error estimation methods, the model is solved numerically on a PC-based Linux cluster with MPI libraries. Quantum mechanical effect plays an important role in semiconductor nanoscale device simulation. To model this effect. a physical-based quantum correction equation is derived and solved with the hydrodynamic transport model. Numerical calculation of the quantum correction transport model is implemented with the parallel adaptive finite volume method which has recently been proposed by us in deep-submicron semiconductor device simulation. A 20 nm double-gate MOSFET is simulated with the developed quantum transport model and computational technique. Compared with a classical transport model. it is found that this model can account for the quantum mechanical effects of the nanoscale double-gate MOSFET quantitatively. Various biasing conditions have been verified on the simulated device to demonstrate its accuracy. Furthermore. for the same tested problem, the parallel adaptive computation shows very good computational performance in terms of the mesh refinements, the parallel speedup, the load-balancing, and the efficiency. (C) 2004 Elsevier B.V. All rights reserved.
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