Local mesh refinement is one of the key steps in the implementations of adaptive finite element methods. This paper presents a parallel algorithm for distributed memory parallel computers for adaptive local refinement...
详细信息
Local mesh refinement is one of the key steps in the implementations of adaptive finite element methods. This paper presents a parallel algorithm for distributed memory parallel computers for adaptive local refinement of tetrahedral meshes using bisection. This algorithm is used in PHG, parallel Hierarchical Grid Chttp：//lsec. cc. ac. cn/phg/）, a toolbox under active development for parallel adaptive finite element solutions of partial differential equations. The algorithm proposed is characterized by allowing simukaneous refinement of submeshes to arbitrary levels before synchronization between submeshes and without the need of a central coordinator process for managing new vertices. Using the concept of canonical refinement, a simple proof of the independence of the resulting mesh on the mesh partitioning is given, which is useful in better understanding the behaviour of the biseetioning refinement procedure.
In this article the relevance of using test methods of pattern recognition while developing intelligent systems for decision making support for various problem areas is discussed. The advantage of fault-tolerant diagn...
详细信息
In this article the relevance of using test methods of pattern recognition while developing intelligent systems for decision making support for various problem areas is discussed. The advantage of fault-tolerant diagnostic tests used in intelligent systems is shown, namely, a tool for registering and processing different kinds of errors in databases and knowledge bases. The results of testing two algorithms for constructing the nonredundant matrix of implications are compared;the technical particulars of program implementation are discussed such as synchronization means, test environment, test-program structure, and bottlenecks of program implementation;methods of their elimination, and further development of parallel algorithms.
In this paper, the problem of A-order of binary tree is studied with the PRAM (parallel Random Access Machine) model of parallel computation and a parallel algorithm for A-order of binary tree is proposed. The process...
详细信息
ISBN:
(纸本)9780769535579
In this paper, the problem of A-order of binary tree is studied with the PRAM (parallel Random Access Machine) model of parallel computation and a parallel algorithm for A-order of binary tree is proposed. The process of the parallel algorithm is proceed with detailed description and verified analysis with an application instance. The parallel algorithm of A-order of binary tree provides using and reference for applying it to binary tree traverse sequence and solving the parallelism problem of application program.
Hashing algorithms are used widely in information security area. Having studied the characteristics of traditional cryptographic hashing function and considered the features of multi-core cryptographic processor, this...
详细信息
ISBN:
(纸本)9781509028146
Hashing algorithms are used widely in information security area. Having studied the characteristics of traditional cryptographic hashing function and considered the features of multi-core cryptographic processor, this paper proposes a parallel algorithm for hash computation well-suited to multi core cryptographic processor. The algorithm breaks the chain dependencies of the standard hash function by implementing recursive hash to get faster hash implementation. We discuss the theoretical foundation for our mapping framework including security measure and performance measure. The experiments are performed on a PC with a PCIE card including multi-core cryptographic processor as the cipher processing engine. The results show a performance gain by an approximate factor of 7.8 when running on the 8-core cryptographic processor.
Since the era of data explosion, data mining in large transactional databases has become more and more important. There are many data mining techniques like association rule mining, the most important and well-researc...
详细信息
ISBN:
(纸本)9783319957869;9783319957852
Since the era of data explosion, data mining in large transactional databases has become more and more important. There are many data mining techniques like association rule mining, the most important and well-researched one. Furthermore, frequent itemset mining is one of the fundamental but time-consuming steps in association rule mining. Most of the algorithms used in literature find frequent itemsets on search space items having at least a minsup and are not reused for subsequent mining. Therefore, in order to decrease the execution time, some parallel algorithms have been proposed for mining frequent itemsets. Nonetheless, these algorithms merely implement the parallelization of Apriori and FP-Growth algorithms. To deal with this problem, several parallel NPA-FI algorithms are proposed as a new approach in order to quickly detect frequent itemsets from large transactional databases using an array of co-occurrences and occurrences of kernel item in at least one transaction. parallel NPA-FI algorithms are easily used in many distributed file system, namely Hadoop and Spark. Finally, the experimental results show that the proposed algorithms perform better than other existing algorithms.
The knapsack problem is very important in cryptosystem and in number theory. This paper proposes a new parallel algorithm for the knapsack problem where the method of divide and conquer is adopted. Basing on an EREW-S...
详细信息
ISBN:
(纸本)0780378407
The knapsack problem is very important in cryptosystem and in number theory. This paper proposes a new parallel algorithm for the knapsack problem where the method of divide and conquer is adopted. Basing on an EREW-SIMD machine with shared memory, the proposed algorithm utilizes O(2(n/4))(1-epsilon) processors, 0less than or equal to epsilon less than or equal to 1, and O(2(n)) memory to find a solution for the n-element knapsack problem in time O(2(n/4) (2(n/4))epsilon). Thus the cost of the proposed parallel algorithm is O(2(n)), which is optimal, and an improved result over the past researches. Keywords: Knapsack problem, parallel algorithm, optimal algorithm, memory conflicts.
The method of constructing a schedule for parallel algorithm execution is considered in the article. This algorithm takes into account the execution time of each operation of the algorithm and the relationship of oper...
详细信息
ISBN:
(纸本)9783319951713;9783319951706
The method of constructing a schedule for parallel algorithm execution is considered in the article. This algorithm takes into account the execution time of each operation of the algorithm and the relationship of operations on the data. The method is based on an information graph in which the nodes are the operations of the algorithm, and the edges are the directions of the data transfer. As a result of the interchange of operations between computing nodes, it is possible to achieve a reduction in the execution time of the algorithm by reducing the time spent on data transfer between computing nodes and reducing the downtime of computational nodes. The algorithm can be applied both in parallel programming and in adjacent areas, for example, when scheduling tasks in distributed systems.
Word2Vec, (Word to Vector) processes natural language by calculating the cosine similarity. However, the serial algorithm of original Word2Vec fails to satisfy the demands of training of corpus text because of the exp...
详细信息
ISBN:
(纸本)9781538635247
Word2Vec, (Word to Vector) processes natural language by calculating the cosine similarity. However, the serial algorithm of original Word2Vec fails to satisfy the demands of training of corpus text because of the explosive growth of information. It has become the bottleneck owing to its comparatively low processing efficiency. The High Performance Computing (HPC) specializes in improving the calculation efficiency;therefore, the training efficiency of corpus texts can be greatly improved by parallelizing Word2Vec algorithm. After analyzing the characteristics of the Word2Vec algorithm in detail, we design and implement a parallel Word2Vec algorithm and use it to train corpus text on HPC. Furthermore, the corpus texts of different sizes are collected and trained, and the speed-up ratio is calculated by using the serial algorithm and parallel algorithm of Word2Vec, respectively. The experimental results show that there is a higher speed-up ratio when using the Word2Vec parallel algorithm running on HPC.
Graph can be used as a significant model to simulate the real world. We can find this kind of models in many different fields, such as transportation, navigation, logistics, management and social networks. In such gra...
详细信息
ISBN:
(纸本)9789881563958
Graph can be used as a significant model to simulate the real world. We can find this kind of models in many different fields, such as transportation, navigation, logistics, management and social networks. In such graphs, a circuit is often regarded as a closed-loop way by which information propagates. There are several algorithms for finding all elementary circuits. Among these algorithms, Jonson's algorithm suffers the lowest time complexity so far. In this paper, we introduce a parallel algorithm based on Johnson's algorithm. We demonstrate that it is capable to handle large-scale graphs with a computing cluster. Experiments on both synthetic and real-world data sets demonstrate the effectiveness of the proposed algorithm.
In this paper, a scalable iterative projection-type algorithm for solving non-stationary systems of linear inequalities is considered. A non-stationary system is understood as a large-scale system of inequalities in w...
详细信息
In this paper, a scalable iterative projection-type algorithm for solving non-stationary systems of linear inequalities is considered. A non-stationary system is understood as a large-scale system of inequalities in which coefficients and constant terms can change during the calculation process. The proposed parallel algorithm uses the concept of pseudo-projection which generalizes the notion of orthogonal projection. The parallel pseudo-projection algorithm is implemented using the parallel BSF-skeleton. An analytical estimation of the algorithm scalability boundary is obtained on the base of the BSF cost metric. The large-scale computational experiments were performed on a cluster computing system. The obtained results confirm the efficiency of the proposed approach.
暂无评论