This paper describes an improved thinning algorithm for binary images. We improve thinning algorithm from the fundamental properties such as connectivity, one-pixel width, robust to noise and speed. In addition, in or...
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ISBN:
(纸本)0769519601
This paper describes an improved thinning algorithm for binary images. We improve thinning algorithm from the fundamental properties such as connectivity, one-pixel width, robust to noise and speed. In addition, in order to overcome information loss, we integrated the contour and skeleton of pattern and proposed the threshold way. Some fundamental requirements of thinning and the shape of pattern are preserved very well. Algorithm is very robust to noise and eliminate some spurious branch. Above all, it can overcome the loss of information in pattern. Experimental results show the performance of the proposed algorithm.
In this paper, we propose a parallel algorithm for mining maximal frequent itemsets from databases. A frequent itemset is maximal if none of its supersets is frequent. The new parallel algorithm is named parallel max-...
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In this paper, we propose a parallel algorithm for mining maximal frequent itemsets from databases. A frequent itemset is maximal if none of its supersets is frequent. The new parallel algorithm is named parallel max-miner (PMM), and it is a parallel version of the sequential max-miner algorithm by R.J. Bayardo (1998). Most of existing mining algorithms discover the frequent k-itemsets on the kth pass over the databases, and then generate the candidate (k + 1)-itemsets for the next pass. Compared to those level-wise algorithms, PMM looks ahead at each pass and prunes more candidate itemsets by checking the frequencies of their supersets. We implemented PMM on a cluster of workstations, and evaluated its performance for various cases. PMM demonstrated better performance than other sequential and parallel algorithms, and its performance is quite scalable, even when there are large maximal frequent itemsets (i.e. long patterns) in databases.
We propose two randomized protocols by which n (n not known) initially identical stations of a Packet Radio Network (PRN) are assigned ID numbers from 1 to n to distinguish them. They run regardless of the number of s...
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We propose two randomized protocols by which n (n not known) initially identical stations of a Packet Radio Network (PRN) are assigned ID numbers from 1 to n to distinguish them. They run regardless of the number of stations per channel. The first one is a naive protocol and is derived from recursive probabilistic divide-and-conquer techniques. It requires n/ln k broadcast rounds, where k is the number of communication channels. The second solution needs the well-known prefix sums algorithm and we show that in this scenario the described protocol terminates in 0(n/k) broadcast rounds on the average case whenever k less than or equal to n/ln n. These results are obtained by means of the average case analysis of algorithms, using probabilistic generating functions and formal methods. Surprisingly, our last protocol performs as well as the efficiency-oriented protocol of Hayashi et al. in [1,2], which depends on the number of stations per channel. And moreover, it can handle the case where k is an element of [n/3 Inn, n/ln n]. Copyright (C) 2003 John Wiley Sons, Ltd.
This paper constructs a class of parallel BDF algorithms for the systems of delay differential equations with explicit BDF methods as predictor and implicit BDF methods as corrector. In the paper the stability analysi...
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This paper constructs a class of parallel BDF algorithms for the systems of delay differential equations with explicit BDF methods as predictor and implicit BDF methods as corrector. In the paper the stability analysis is .discussed, and a sufficient condition under which the systems of delay differential equations are asymptotically stable is derived. It is easily inferred that the stability of the algorithm is controlled by the stability of the corresponding ordinary differential equations. Some results of numerical tests are also presented. From theoretical analysis and numerical tests the conclusion can be drawn that the algorithm is not only for linear problems, but also for nonlinear problems.
Artificial intelligence has devised solutions for scheduling problems that haven't been already applied to building-automation specific issues and could be beneficial. This paper presents one of these methods, a p...
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Artificial intelligence has devised solutions for scheduling problems that haven't been already applied to building-automation specific issues and could be beneficial. This paper presents one of these methods, a parallel-genetic algorithm for the optimisation of a multi-objective demand-side management system, and outlines the design of the architecture that supports the use of that algorithm.
A number of parallel algorithms have been developed to solve large-scale real world problems. Although there has been much work on the design of parallel algorithms, there has been little on the design of Languages fo...
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A number of parallel algorithms have been developed to solve large-scale real world problems. Although there has been much work on the design of parallel algorithms, there has been little on the design of Languages for expressing these algorithms. This paper describes the BPL, a new parallel language designed for butterfly networks. The purpose of this language is to help designers in hiding the complexity of the algorithm and leaving details of mapping between data and processors for lower level. BPL provides a simpler virtual machine for the designer, in order to avoid thinking about control of processors and data. From another point of view, BPL helps designer to logically check the algorithm and correct ang. possible error in it. The paper gives some examples implemented by this language. In addition, we have also implemented a software toot which simulates the running of the algorithm on the network. The results lead us to believe that this language would be useful in representing all kinds of algorithms on this network including normal algorithms and others.
A new method for finding connected components from binary images is presented in this article. The main step of this method is to use a contour tracing technique to detect component contours and also to fill in interi...
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ISBN:
(纸本)0769519601
A new method for finding connected components from binary images is presented in this article. The main step of this method is to use a contour tracing technique to detect component contours and also to fill in interior areas. All the component points are traced by this algorithm in a single pass and are assigned either a new label or the same label as their neighboring pixels. Experimenting on various types of document images (characters, pictures, newspapers, etc.), we find that our method outperforms the other sequential methods using the equivalence technique. Our algorithm, moreover, is a method that not only labels components but also extracts component contours at the same time, which proves to be more useful than those algorithms that only label components.
Mining sequential patterns in large database is an important problem in data mining research. Enormous sizes of available datasets and possibly large number of mined patterns demand efficient and scalable algorithms. ...
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ISBN:
(纸本)0780378652
Mining sequential patterns in large database is an important problem in data mining research. Enormous sizes of available datasets and possibly large number of mined patterns demand efficient and scalable algorithms. In this paper, we present a new dynamic load algorithm based HPSPM (hash-based parallel algorithm for mining sequential patterns) on shared-nothing environment. Experiments on Dawning 300 cluster system show that this algorithm achieves good speedup and is substantially improved compared to HPSPM.
We propose an asynchronous parallel algorithm for the linear Boltzmann transport equation in three dimensions, for Boron Neutron Capture Therapy (BNCT) radiation therapy planning, which can be implemented efficiently ...
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We propose an asynchronous parallel algorithm for the linear Boltzmann transport equation in three dimensions, for Boron Neutron Capture Therapy (BNCT) radiation therapy planning, which can be implemented efficiently on shared memory parallel computers. The three-dimensional multigroup discrete ordinates transport equation is cast into a set of coupled two-dimensional equations, and discretization is accomplished on a grid of arbitrarily-shaped prismatic cells. This allows the 3D multigroup discrete ordinates transport equation to be solved using spatial parallel techniques originally developed in a recent work for the 2D discrete ordinates transport equation by using domain decomposition techniques on an unstructured triangular mesh. We use the single program multiple data approach to formulate a shared memory parallel numerical implementation with OpenMP. Our results demonstrate that the parallel version of the 3D deterministic algorithm yields good parallel efficiency.
Global optimization is playing an increasing role in physics, chemistry, and biophysical chemistry. One of the most important applications of global optimization is to find the global minima of the potential energy of...
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Global optimization is playing an increasing role in physics, chemistry, and biophysical chemistry. One of the most important applications of global optimization is to find the global minima of the potential energy of molecules or molecular assemblies, such as crystals. The solution of this problem typically requires huge computational effort. Even the fastest processor available is not fast enough to carry out this kind of computation in real time for the problems of real interest, e.g., protein and crystal structure prediction. One way to circumvent this problem is to take advantage of massively parallel computing. In this paper, we provide several examples of parallel implementations of global optimization algorithms developed in our laboratory. All of these examples follow the master/worker approach. Most of the methods are parallelized on the algorithmic (coarse-grain) level and one example of fine-grain parallelism is given, in which the function evaluation itself is computationally expensive. All parallel algorithms were initially implemented on an IBM/SP2 (distributed-memory) machine. In all cases, however, message passing is handled through the standard Message Passing Interface (MPI);consequently the algorithms can also be implemented on any distributed- or shared-memory system that runs MPI. The efficiency of these implementations is discussed. (C) 2000 Elsevier Science B.V. All rights reserved.
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