检索结果-内蒙古大学图书馆

parallel alternating direction method of multipliers

INFORMATION SCIENCES 2020年 507卷 185-196页

作者： Yan, Jiaqi Guo, Fanghong Wen, Changyun Li, Guoqi Nanyang Technol Univ Singapore Singapore Zhejiang Univ Technol Hangzhou Zhejiang Peoples R China Tsinghua Univ Beijing Peoples R China

In this paper, we consider the distributed optimization problem, where the objective function is the sum of local cost functions. To solve this problem, a new parallel Alternating Direction Method of Multipliers (ADMM) algorithm is developed, which guarantees that the agents cooperatively reach an optimal agreement. Different from most of the existing ADMM approaches, our algorithm allows all the agents to update their local variables simultaneously in a parallel manner. It is theoretically proved that the local solutions of all the agents could reach a consensus, and converge to the optimal solution asymptotically with the rate of O(1/k). Numerical examples are finally provided to validate the effectiveness of the proposed method. (C) 2019 Elsevier Inc. All rights reserved.

关键词： Distributed optimization ADMM parallel algorithm

来源：评论

学校读者我要写书评

暂无评论

parallel pressure projection stabilized finite element algorithms based on two-grid discretizations for incompressible flows

引用

INTERNATIONAL JOURNAL OF COMPUTER MATHEMATICS 2020年第8期97卷 1563-1585页

作者： Zheng, Bo Zhou, Kangrui Shang, Yueqiang Southwest Univ Sch Math & Stat Chongqing 400715 Peoples R China

Based on two-grid discretizations, three parallel pressure projection stabilized finite element algorithms are investigated and compared for solving the steady-state incompressible Navier-Stokes equations. In these parallel stabilized algorithms, a global stabilized nonlinear problem is first solved by Oseen iterative method on a coarse grid, and then local stabilized and linearized problems are independently solved on overlapping local fine grid, where the stabilization terms are based on two local Gauss integrations for the coarse and fine grid problems. Theoretical results show that with appropriate scalings of the algorithmic parameters, the proposed algorithms can yield an optimal convergence rate. Some numerical examples are also provided to verify the correctness of theoretical predictions and demonstrate the high efficiency of the algorithms.

关键词： Navier-Stokes equations two-grid discretizations parallel algorithm finite element pressure projection stabilization

来源：评论

学校读者我要写书评

暂无评论

Efficient discovery of co-location patterns from massive spatial datasets with or without rare features

引用

KNOWLEDGE AND INFORMATION SYSTEMS 2021年第6期63卷 1365-1395页

作者： Yang, Peizhong Wang, Lizhen Wang, Xiaoxuan Zhou, Lihua Yunnan Univ Sch Informat Sci & Engn Kunming 650091 Peoples R China

A co-location pattern indicates a group of spatial features whose instances are frequently located together in proximate geographic area. Spatial co-location pattern mining (SCPM) is valuable for many practical applications. Numerous previous SCPM studies emphasize the equal participation per feature. As a result, the interesting co-locations with rare features cannot be captured. In this paper, we propose a novel interest measure, i.e., the weighted participation index (WPI), to identify co-locations with or without rare features. The WPI measure possesses a conditional anti-monotone property which can be utilized to prune the search space. In addition, a fast row instance identification mechanism based on the ordered NR-tree is proposed to enhance efficiency. Subsequently, the ordered NR-tree-based algorithm is developed. To further improve efficiency and process massive spatial data, we break the ordered NR-tree into multiple independent subtrees, and parallelize the ordered NR-tree-based algorithm on MapReduce framework. Extensive experiments are conducted on both real and synthetic datasets to verify the effectiveness, efficiency and scalability of our techniques.

关键词： Spatial data mining Co-location pattern Rare feature parallel algorithm

来源：评论

学校读者我要写书评

暂无评论

k-Integer-Merging on Shared Memory

引用

INTERNATIONAL JOURNAL OF ADVANCED COMPUTER SCIENCE AND APPLICATIONS 2021年第1期12卷 685-691页

作者： Khedr, Ahmed Y. Alseadoon, Ibrahim M. Univ Hail Coll Comp Sci & Engn Hail Saudi Arabia Al Azhar Univ Fac Engn Syst & Comp Dept Cairo Egypt

The k integer-merging problem is to merge the k sorted arrays into a new sorted array that contains all elements of A(i), for all i . We propose a new parallel algorithm based on exclusive read exclusive write shared memory. The algorithm runs in O(log n) time using n/ log n processors. The algorithm performs linear work, O(n), and has optimal cost. Furthermore, the total work done by the algorithm is less than the best-known previous parallel algorithms for k merging problem.

关键词： Merging parallel algorithm shared memory optimality linear work

来源：评论

学校读者我要写书评

暂无评论

A 3D frequency-domain electromagnetic solver employing a high order compact finite-difference scheme

引用

COMPUTERS & GEOSCIENCES 2023年第1期178卷

作者： Vilanakis, N. D. Economou, N. Mathioudakis, E. Vafidis, A. Tech Univ Crete Appl Math & Comp Lab Univ Campus Khania 73100 Greece Tech Univ Crete Sch Mineral Resources Engn Appl Geophys Lab Univ Campus Khania 73100 Greece Sultan Qaboos Univ Coll Sci Earth Sci Dept Al Khoud 123 Oman

Three-dimensional (3D) electromagnetic (EM) modeling is an important tool for geophysical applications. In EM induction methods the modified Helmholtz equation is often used to describe scattered or residual electric fields in three dimensions. Throughout this paper, a high order compact finite difference scheme for the solution of that equation for vertical magnetic dipole source (VMD) is presented. The approximation of the residual electric field intensity using a fourth order compact finite difference (FD) discretizer is achieved with the solution of a block linear system, the coefficient matrices are large and sparse with a particular structure, implying the application of a matrix-free Krylov subspace method for an efficient numerical solution. The proposed solver is being examined using a number of test problems in uniform and non-uniform grid spacing where numerical and analytical solutions for the homogeneous half-space cases are being compared.

关键词： EM induction Method FDFD Solver High -order scheme parallel algorithm

来源：评论

学校读者我要写书评

暂无评论

Impact of grid partitioning algorithms on combined distributed AC optimal power flow and parallel dynamic power grid simulation

引用

IET GENERATION TRANSMISSION & DISTRIBUTION 2020年第25期14卷 6133-6141页

作者： Kyesswa, Michael Murray, Alexander Schmurr, Philipp Cakmak, Hueseyin Kuehnapfel, Uwe Hagenmeyer, Veit Karlsruhe Inst Technol Inst Automat & Appl Informat Karlsruhe Germany

The complexity of most power grid simulation algorithms scales with the network size, which corresponds to the number of buses and branches in the grid. parallel and distributed computing is one approach that can be used to achieve improved scalability. However, the efficiency of these algorithms requires an optimal grid partitioning strategy. To obtain the requisite power grid partitionings, the authors first apply several graph theory based partitioning algorithms, such as the Karlsruhe fast flow partitioner (KaFFPa), spectral clustering, and METIS. The goal of this study is an examination and evaluation of the impact of grid partitioning on power system problems. To this end, the computational performance of AC optimal power flow (OPF) and dynamic power grid simulation are tested. The partitioned OPF-problem is solved using the augmented Lagrangian based alternating direction inexact Newton method, whose solution is the basis for the initialisation step in the partitioned dynamic simulation problem. The computational performance of the partitioned systems in the implemented parallel and distributed algorithms is tested using various IEEE standard benchmark test networks. KaFFPa not only outperforms other partitioning algorithms for the AC OPF problem, but also for dynamic power grid simulation with respect to computational speed and scalability.

关键词： Newton method optimisation load flow IEEE standards power grids graph theory pattern clustering parallel algorithms power system simulation computational complexity optimal grid partitioning strategy spectral clustering power system problems computational performance partitioned OPF-problem augmented Lagrangian based alternating direction inexact Newton method partitioned dynamic simulation problem partitioned systems parallel algorithm distributed algorithms AC OPF problem grid partitioning algorithms combined distributed AC optimal power flow parallel dynamic power grid simulation distributed computing power grid simulation algorithms power grid partitionings parallel computing graph theory Karlsruhe fast flow partitioner KaFFPa METIS IEEE standard benchmark test networks

来源：评论

学校读者我要写书评

暂无评论

parallel MOEA Based on Consensus and Membrane Structure for Inferring Phylogenetic Reconstruction

引用

IEEE ACCESS 2020年 8卷 6177-6189页

作者： Zhang, Qianqian Zhang, Jun Zhong, Yue Ye, Congming Min, Xiaoping Xiamen Univ Dept Comp Sci Xiamen 361005 Peoples R China Heilongjiang Prov Land Reclamat Headquarters Gen Rehabil Dept Harbin 150088 Peoples R China

In recent years, inferring phylogenies has attracted lots of attention in both academic community and various application fields. Phylogenetic inference usually consists of a couple of evolutionary relationships, which can be represented as a phylogenetic tree. The phylogenetic reconstruction problem can be defined as an optimization problem, targeting at finding the most eligible tree among all possible topologies according to a selected criterion. Since the combinatorial number of possible topologies exceeds tolerance, various heuristic and metaheuristic methods have been proposed to find approximate solutions according to the selected criterion. However, different criterions are based on different principle and conflict with each other basically. In this line, scholars has proposed multi-objective evolutionary algorithm (MOEA) based on diverse criteria. Nevertheless, MOEA has suffered unbearable time consumption due to its inherent drawbacks of computational complexity and convergence. By studying the independence between the sub-populations in each time-consuming step of MOEA, the steps without global information can be designed to be executed in parallel, which can fundamentally address computational problems. Effective parallel algorithms designed with the characteristics of modern multicore clusters can solve such problems. In this sense, we propose a parallelized multi-objective evolutionary algorithm (MOEA-MC) by deploying on Spark, which added consensus into evolutionary algorithm to improve the quality of convergence and used membrane structure to keep equal solutions under different weights. In order to assess the performance achieved by the proposal, we have performed comparison among different methods on three real-world datasets separately. The results have certified that the solutions derived from MOEA-MC are superior to traditional methods in all studied datasets. And parallelized MOEA-MC can get dominant position and optimal Pareto-frontier simulta

关键词： Consensus multi-objective evolutionary algorithm membrane structure phylogenetic reconstruction parallel algorithm

来源：评论

学校读者我要写书评

暂无评论

An Efficient parallel Computing Method for the Steady-State Analysis of Electric Machines Using the Woodbury Formula

引用

IEEE TRANSACTIONS ON MAGNETICS 2020年第2期56卷 1-4页

作者： He, B. Lu, C. Chen, N. Lin, D. Zhou, P. ANSYS Inc Canonsburg PA 15317 USA

This article describes a parallel computing method for the steady-state analysis of electric machines. In this method, due to the low rank of the coupling sub-matrix, the Woodbury formula is exploited to develop a highly efficient parallel algorithm to solve the formulated linearized block matrix. The algorithm and the analysis of the computational complexity are worked out in detail. The performance of the algorithm is demonstrated by an application example.

关键词： Electric machine parallel algorithm

来源：评论

学校读者我要写书评

暂无评论

Robust active yaw control for offshore wind farms using stochastic predictive control based on online adaptive scenario generation

引用

OCEAN ENGINEERING 2023年第Part2期286卷

作者： Wang, Yu Wei, Shanbi Yang, Wei Chai, Yi Chongqing Univ Coll Automat Chongqing 400044 Peoples R China CSSC Haizhuang Wind Power Co Ltd Chongqing 400044 Peoples R China Chongqing Univ State Key Lab Power Transmiss Equipment & Syst Sec Chongqing 400044 Peoples R China

Subject to the inherent high uncertainty of wind, the prediction for its speed and direction may be insufficiently accurate, the resulting decision actions of active yaw control (AYC) may degrade the power gain. Therefore, this paper proposes a data-driven stochastic model predictive control (SMPC) using adaptive scenario generation (ASG) for offshore wind farm AYC. First, to build precise scenarios under the nonstationary variation of wind, an adaptive method based on Gaussian mixture model (GMM) clustering is proposed to allow online scenario identification with a compact construction. Specifically, GMM is constructed offline and two online mechanisms are developed for adaptive learning ability. To immunize the power maximization of AYC against prediction error, a data-driven robust optimization strategy is presented to realize SMPC based on generated scenarios. In order to enable real-time operation for large-scale wind farms, a novel parallel marine predator algorithm (PMPA) introduced population improvement strategy is developed to solve the robust problems with a quite lower computational burden. Finally, the simulation based on realistic wind data demonstrates the adaptive learning capacity of the proposed ASG. The result shows that the SMPC can improve the power gain by an average of 2.64% compared to the baseline predictive control.

关键词： Active yaw control Wind uncertainty Stochastic predictive control Adaptive scenario generation Offshore wind farm parallel algorithm

来源：评论

学校读者我要写书评

暂无评论

EXPANDABLE parallel FINITE ELEMENT METHODS FOR LINEAR ELLIPTIC PROBLEMS

引用

Acta Mathematica Scientia 2020年第2期40卷 572-588页

作者： Guangzhi DU School of Mathematics and Statistics Shandong Normal UniversityJinan 250014China

In this article,two kinds of expandable parallel finite element methods,based on two-grid discretizations,are given to solve the linear elliptic *** with the classical local and parallel finite element methods,there are two attractive features of the methods shown in this article:1)a partition of unity is used to generate a series of local and independent subproblems to guarantee the final approximation globally continuous;2)the computational domain of each local subproblem is contained in a ball with radius of O(H)(H is the coarse mesh parameter),which means methods in this article are more suitable for parallel computing in a large parallel computer *** a priori error estimation are obtained and optimal error bounds in both H^1-normal and L^2-normal are ***,numerical results are reported to test and verify the feasibility and validity of our methods.

关键词： Two-grid method expandable method partition of unity parallel algorithm finite element method

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：