Network motifs have been demonstrated to be the building blocks in many biological networks such as transcriptional regulatory networks. Finding network motifs plays a key role in understanding system level functions ...
详细信息
The paper presents a Coarse-Grained Multicomputer algorithm that solves the problem of detection of repetitions. This algorithm can be implemented in the CGM model with P processors in O(N-2/p) in time and O(P) commun...
详细信息
The paper presents a Coarse-Grained Multicomputer algorithm that solves the problem of detection of repetitions. This algorithm can be implemented in the CGM model with P processors in O(N-2/p) in time and O(P) communication steps. It is the first CGM algorithm for this problem. We present also experimental results showing that the CGM algorithm is very efficient. (C) 2004 Elsevier B.V. All rights reserved.
We present randomized and deterministic algorithms for many-to-one packet routing on an n-node two-dimensional mesh under the store-and-forward model. We consider the general instance of many-to-one routing where each...
详细信息
We present randomized and deterministic algorithms for many-to-one packet routing on an n-node two-dimensional mesh under the store-and-forward model. We consider the general instance of many-to-one routing where each node is the source (resp., destination) of l (resp., k) packets, for arbitrary values of l and k. All our algorithms run in optimal O(root lkn) time and use queues of only constant size at each node to store packets in transit. The randomized algorithms, however, are simpler to implement. Our result closes a gap in the literature, where time-optimal algorithms using constant-size queues were known only for the special cases l = 1 and l = k. (c) 2005 Published by Elsevier B.V.
Many physical phenomena are modeled by nonclassical parabolic boundary value problems with nonlocal boundary conditions. In place of the classical specification of boundary data, we impose a nonlocal boundary conditio...
详细信息
Many physical phenomena are modeled by nonclassical parabolic boundary value problems with nonlocal boundary conditions. In place of the classical specification of boundary data, we impose a nonlocal boundary condition. Partial differential equations with nonlocal boundary conditions have received much attention in the last twenty years. Most of the papers were directed to the second-order parabolic equation, particularly to the heat conduction equation. One could generically classify these problems into two types;boundary value problems with nonlocal initial conditions, and boundary value problems with nonlocal boundary conditions. We will deal here with the second type of nonlocal boundary value problems that is the solution of nonlocal boundary value problems with standard initial condition. The main difficulty in the implicit treatment of the nonlocal boundary value problems is the nonclassical form of the resulting matrix of the system of linear algebraic equations. In this paper, various approaches for the numerical solution of the one-dimensional heat equation subject to the specification of mass which have been considered in the literature, are reported. Several methods have been proposed for the numerical solution of this boundary value problem. Some remarks comparing our work with earlier work will be given throughout the paper. Numerical examples are given at the end of this paper to compare the efficiency of the new techniques. Some specific applications in engineering models are introduced. (C) 2004 IMACS. Published by Elsevier B.V. All rights reserved.
In the literature, there are quite a few sequential and parallel algorithms to solve problems on decomposable graphs utilizing distinct techniques. Trees, series-parallel graphs, outerplanar graphs, and bandwidth-k gr...
详细信息
In the literature, there are quite a few sequential and parallel algorithms to solve problems on decomposable graphs utilizing distinct techniques. Trees, series-parallel graphs, outerplanar graphs, and bandwidth-k graphs all belong to decomposable graphs. Let T-d (\V\, \E\) and P-d (\V\, \E\) denote the time complexity and processor complexity required to construct a parse tree representation T-G for a decomposable graph G = (V, E) on a PRAM model M-d. We define a general problem-solving paradigm to solve a wide class of subgraph optimization problems on decomposable graphs in O(T-d(\V\, \E\) +log \V(T-G)\) time using O(P-d(\V\, \E\) + (\V( TG)\)/(log \V\(TG)\)) processors on M-d. We also demonstrate the following examples fitting into our paradigm: (1) The maximum independent set problem on trees, (2) The maximum matching problem on series-parallel graphs, and (3) The efficient domination problem on series-parallel graphs. Our results improve the previously best known results of (1) and (2). (C) 2004 Elsevier Inc. All rights reserved.
In this paper a new partitioning algorithm for parallelization of post-placement VLSI procedures is presented. The partitioning technique divides problem tasks into multiple sessions of parallel processes, so that int...
详细信息
A longest common subsequence (LCS) of two strings is a common subsequence of two strings of maximal length. The LCS problem is to find an LCS of two given strings and the length of the LCS (LLCS). In this paper, we pr...
详细信息
A longest common subsequence (LCS) of two strings is a common subsequence of two strings of maximal length. The LCS problem is to find an LCS of two given strings and the length of the LCS (LLCS). In this paper, we present a new linear processor array for solving the LCS problem. The array is based on parallelization of a recent LCS algorithm which consists of two phases, i.e. preprocessing and computation. The computation phase is based on bit-level dynamic programming approach. Implementations of the preprocessing and computation phases are discussed on the same processor array architecture for the LCS problem. Further, we propose a block processor array architecture which reduces the overall communication and time requirements. Finally, we develop a performance model for estimating the performance of the processor array architecture on Pentium processors.
Recently, researchers have proposed many models using reconfigurable optically pipelined buses. Most algorithms developed for these models assume that a healthy system is available. The only previous work in this area...
详细信息
Recently, researchers have proposed many models using reconfigurable optically pipelined buses. Most algorithms developed for these models assume that a healthy system is available. The only previous work in this area considers faulty processors or hardware for an N-processor linear array with a reconfigurable pipelined bus system (LARPBS), resulting in fault tolerant algorithms that run in O(log N) time. We extend and improve upon previous results by considering new fault scenarios and slight modifications to the LARPBS model. By modifying the switches on the receiving segment of an LARPBS, a reasonable, low-cost extension to the model, we are able to achieve fault tolerant algorithms that execute in O(1) time rather than O(log N) time. The fault tolerant algorithms that we consider are key basic fundamental algorithms, such as compaction, binary prefix sums, and sorting, that all execute in constant time on a healthy LARPBS. As the algorithms improved are building blocks for more complex algorithms, the results presented in this paper will extend to those more complex algorithms as well. (c) 2004 Elsevier Inc. All rights reserved.
In this paper, we analyze the communication pattern and study the scalability of a distributed memory implementation of the multilevel fast multipole algorithm (MLFMA) called ScaleME. ScaleME uses the message passing ...
详细信息
In this paper, we analyze the communication pattern and study the scalability of a distributed memory implementation of the multilevel fast multipole algorithm (MLFMA) called ScaleME. ScaleME uses the message passing interface (MPI) for communication between processors. The parallelization of MLFMA uses a novel a hybrid scheme for distributing the workload across the processors. We study the communication and computational behavior and demonstrate the effectiveness of the parallelization scheme using realistic problems.
The task of choice and allocation of the area region's objects on the image, is well-known and in detail investigated, so on the basis of the developed theoretical recommendations there are also many programming d...
详细信息
ISBN:
(纸本)0889864772
The task of choice and allocation of the area region's objects on the image, is well-known and in detail investigated, so on the basis of the developed theoretical recommendations there are also many programming decisions usually used in various spheres of a national economy: geology, a forestry, ecological monitoring etc. The transfering of existed and known algorithms and programs at the consecutive computers into the parallel computing architecture and the distributed computational structures for data processing becames the very actual problem. Geoinformation systems deal with allocation of the area objects at the aero-space images. The parallel analysis of area regions appears essentially more difficult, and results in necessity of identification of the objects. The mathematical aspects of the identification problem may be expressed in theorems of existence and uniqueness of identifying attributes for the given type of Decart's metrics. The work was carried out partly with financial sponsoring of projects RFBR (No 05-07-90057-B, No 05-05-98006-p_oob_a, No 05-07-98011-p_oob,_B.).
暂无评论