检索结果-内蒙古大学图书馆

ANALYSIS OF decomposition algorithms VIA NON-LINEAR SPLITTING FUNCTIONS

JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS 1981年第3期34卷 371-382页

作者： LOOZE, DP SANDELL, NR MIT INFORMAT & DECIS SCI LABCAMBRIDGEMA 02139

This paper provides a structural analysis of decomposition algorithms using a generalization of linear splitting methods. This technique is used to identify explicitly the essential similarities and differences between several classical algorithms. Similar concepts can be used to analyze a large class of multilevel hierarchical structures.

关键词： Hierarchical control decomposition algorithms convergence rates iterative algorithms

来源：评论

学校读者我要写书评

暂无评论

CONVERGENCE BEHAVIOR OF decomposition algorithms FOR LINEAR-PROGRAMS

引用

OPERATIONS RESEARCH LETTERS 1984年第2期3卷 91-94页

作者： HO, JK Management Science Program College of Business Administration The University of Tennessee Knoxville TN 37996 USA

This paper discusses plausible explanations of the somewhat folkloric, ‘tailing off’ convergence behavior of the Dantzig-Wolfe decomposition algorithm for linear programs. Is is argued that such beahvior may be used... 详细信息

关键词： linear programming decomposition algorithms convergence behavior large scale systems

来源：评论

学校读者我要写书评

暂无评论

Comparison of decomposition algorithms for identification of single motor units in ultrafast ultrasound image sequences of low force voluntary skeletal muscle contractions

引用

BMC RESEARCH NOTES 2022年第1期15卷 1-7页

作者： Rohlen, Robin Yu, Jun Gronlund, Christer Umea Univ Dept Radiat Sci Biomed Engn S-90187 Umea Sweden Umea Univ Dept Math & Math Stat S-90187 Umea Sweden

Objective In this study, the aim was to compare the performance of four spatiotemporal decomposition algorithms (stICA, stJADE, stSOBI, and sPCA) and parameters for identifying single motor units in human skeletal muscle under voluntary isometric contractions in ultrafast ultrasound image sequences as an extension of a previous study. The performance was quantified using two measures: (1) the similarity of components' temporal characteristics against gold standard needle electromyography recordings and (2) the agreement of detected sets of components between the different algorithms. Results We found that out of these four algorithms, no algorithm significantly improved the motor unit identification success compared to stICA using spatial information, which was the best together with stSOBI using either spatial or temporal information. Moreover, there was a strong agreement of detected sets of components between the different algorithms. However, stJADE (using temporal information) provided with complementary successful detections. These results suggest that the choice of decomposition algorithm is not critical, but there may be a methodological improvement potential to detect more motor units.

关键词： Ultrafast ultrasound Concentric needle electromyography Motor units decomposition algorithms Blind source separation

来源：评论

学校读者我要写书评

暂无评论

Optimizing strategic and operational decisions of car sharing systems under demand uncertainty and substitution

引用

COMPUTERS & OPERATIONS RESEARCH 2025年 180卷

作者： Basciftci, Beste Koca, Esra Kosunda, Sinan Emre Univ Iowa Tippie Coll Business Dept Business Analyt Iowa City IA 52242 USA Sabanci Univ Ind Engn Program Istanbul Turkiye

Car sharing is an efficient way to improve mobility, reduce the use of personal vehicles, and lessen the associated carbon emissions. Due to increasing environmental awareness of customers and government regulations, car sharing providers must be careful about the composition of their vehicle fleet to meet diverse customer demand through vehicle types with different carbon emission levels. In this study, for a car sharing company, we consider the problems of determining service regions and purchasing decisions with a mixed fleet of vehicles under budget and carbon emission constraints, and the deployment of these vehicles to service regions under uncertain one-way and round-trip rental requests over a multi-period planning horizon. We further introduce the concept of "substitution" to the car sharing operations that provides customers with alternative vehicle options when their preferred type is unavailable. To address this complex problem, we propose a novel two-stage stochastic mixed-integer program leveraging spatial-temporal networks and multicommodity flows to capture these strategic and operational decisions of this system over the planning horizon while allowing substitution in operations. We further prove that the corresponding second-stage problem of the proposed program has a totally unimodular constraint matrix. Taking advantage of this result, we develop a branch-and-cut-based decomposition algorithm with various computational enhancements. We present an extensive computational study that highlights the value of the proposed models from different perspectives and demonstrates the performance of the proposed solution algorithm with significant speedups. Our case study provides insights for region opening and fleet allocation plans under demand uncertainty and demonstrates the value of introducing substitution to car sharing operations and the importance of integrating strategic and operational decisions and obtaining stochastic solutions.

关键词： Car sharing Substitution Stochastic mixed-integer programming decomposition algorithms Sustainable operations

来源：评论

学校读者我要写书评

暂无评论

Problems and algorithms of Text decomposition by Clauses

引用

AUTOMATIC DOCUMENTATION AND MATHEMATICAL LINGUISTICS 2012年第3期46卷 146-152页

作者： Yatsko, V. A. Katanov Khakas State Univ Abakan Russia

The features of different types of decomposition that are employed in preliminary text processing are considered. Linguistic problems of decomposition by clauses via the transformation of communicative and modal planes of a text are discussed. The grammar and algorithms that are required to perform decomposition by clauses are described.

关键词： decomposition decomposition algorithms predicative structure clauses token

来源：评论

学校读者我要写书评

暂无评论

The berth allocation problem in bulk terminals under uncertainty

引用

Operations Research Perspectives 2025年 14卷

作者： Rodrigues, Filipe ISEG - School of Economics and Management University of Lisbon REM - Research in Economics and Mathematics CEMAPRE Rua do Quelhas 6 Lisboa 1200-781 Portugal

Uncertainty is critical in bulk terminals because it is inherent to many operations. In particular, the berth allocation problem (BAP) is greatly affected by the uncertain arrival times of the vessels. In this paper, we propose the first distributionally robust optimization (DRO) model for the BAP in bulk terminals, where the probability distribution of the arrival times is assumed to be unknown but belongs to an ambiguity set. To solve the model, we use an exact decomposition algorithm (DA) in which the probability distribution information is iteratively included in the master problem through optimal dual cuts. The DA is then enhanced with two improvement strategies to reduce the associated computational time;however, with these strategies, the DA may no longer be exact and is still inefficient for solving large-scale instances. To overcome these issues, we propose a modified exact DA where the dual cuts used in the original DA are replaced by powerful primal cuts that drastically reduce the time required to solve the DRO model, making it possible to handle large-scale instances. The reported computational experiments also show clear benefits of using DRO to tackle uncertainty compared to stochastic programming and robust optimization. © 2025

关键词： Bulk terminals decomposition algorithms Distributionally robust optimization Uncertainty

来源：评论

学校读者我要写书评

暂无评论

decomposition and dynamic cut generation in integer linear programming

引用

MATHEMATICAL PROGRAMMING 2006年第2期106卷 261-285页

作者： Ralphs, TK Galati, MV Lehigh Univ Dept Ind & Syst Engn Bethlehem PA 18015 USA SAS Inst Cary NC USA

decomposition algorithms such as Lagrangian relaxation and Dantzig-Wolfe decomposition are well-known methods that can be used to generate bounds for mixed-integer linear programming problems. Traditionally, these methods have been viewed as distinct from polyhedral methods, in which bounds are obtained by dynamically generating valid inequalities to strengthen an initial linear programming relaxation. Recently, a number of authors have proposed methods for integrating dynamic cut generation with various decomposition methods to yield further improvement in computed bounds. In this paper, we describe a framework within which most of these methods can be viewed from a common theoretical perspective. We then discuss how the framework can be extended to obtain a decomposition-based separation technique we call decompose and cut. As a by-product, we describe how these methods can take advantage of the fact that solutions with known structure, such as those to a given relaxation, can frequently be separated much more easily than arbitrary real vectors.

关键词： integer programming Dantzig-Wolfe decomposition Lagrangian relaxation branch and cut branch and price decomposition algorithms

来源：评论

学校读者我要写书评

暂无评论

On decomposition methods for a class of partially separable nonlinear programs

引用

MATHEMATICS OF OPERATIONS RESEARCH 2008年第1期33卷 119-139页

作者： DeMiguel, Victor Nogales, Francisco J. London Business Sch Management Sci & Operat London NW1 4SA England Univ Carlos III Madrid Dept Stat Madrid Spain

We study two different decomposition algorithms for the general (nonconvex) partially separable nonlinear program (PSP): bilevel decomposition algorithms (BDAs) and Schur interior-point methods (SIPMs). BDAs solve the problem by breaking it into a master problem and a set of independent subproblems, forming a type of bilevel program. SIPMs, on the other hand, apply an interior-point technique to solve the problem in its original (integrated) form, but then use a Schur complement approach to solve the Newton system in a decentralized manner. Our first contribution is to establish a theoretical relationship between these two types of decomposition algorithms. This is a first step toward closing the gap between the incipient local convergence theory of BDAs and the mature local convergence theory of interior-point methods. Our second contribution is to show how SIPMs can be modified to solve problems for which the Schur complement matrix is not invertible in general. The importance of this contribution is that it substantially enlarges the class of problems that can be addressed with SIPMs.

关键词： bilevel programming Schur complement decomposition algorithms

来源：评论

学校读者我要写书评

暂无评论

CONVERGENCE ANALYSIS OF SAMPLING-BASED decomposition METHODS FOR RISK-AVERSE MULTISTAGE STOCHASTIC CONVEX PROGRAMS

引用

SIAM JOURNAL ON OPTIMIZATION 2016年第4期26卷 2468-2494页

作者： Guigues, Vincent FGV EMAp BR-22250900 Rio De Janeiro Brazil

We consider a class of sampling-based decomposition methods to solve risk-averse multistage stochastic convex programs. We prove a formula for the computation of the cuts necessary to build the outer linearizations of the recourse functions. This formula can be used to obtain an efficient implementation of Stochastic Dual Dynamic Programming applied to convex nonlinear problems. We prove the almost sure convergence of these decomposition methods when the relatively complete recourse assumption holds. We also prove the almost sure convergence of these algorithms when applied to risk-averse multistage stochastic linear programs that do not satisfy the relatively complete recourse assumption. The analysis is first done assuming the underlying stochastic process is interstage independent and discrete, with a finite set of possible realizations at each stage. We then indicate two ways of extending the methods and convergence analysis to the case when the process is interstage dependent.

关键词： Stochastic programming risk-averse optimization decomposition algorithms Monte Carlo sampling relatively complete recourse SDDP

来源：评论

学校读者我要写书评

暂无评论

A path decomposition approach for computing blocking probabilities in wavelength-routing networks

引用

IEEE-ACM TRANSACTIONS ON NETWORKING 2000年第6期8卷 747-762页

作者： Zhu, YH Rouskas, GN Perros, HG N Carolina State Univ Dept Comp Sci Raleigh NC 27695 USA N Carolina State Univ Dept Comp Sci Raleigh NC 27695 USA

We study a class of circuit-switched wavelength-routing networks with fixed or alternate routing and with random wavelength allocation. We present an iterative path decomposition algorithm to evaluate accurately and efficiently the blocking performance of such networks with and without wavelength converters. Our iterative algorithm analyzes the original network by decomposing it into single-path subsystems. These subsystems are analyzed in isolation, and the individual results are appropriately combined to obtain a solution for the overall network, To analyze individual subsystems, we first construct an exact Markov process that captures the behavior of a path in terms of wavelength use. We also obtain an approximate Markov process which has a closed-form solution that can be computed efficiently for short paths, We then develop an iterative algorithm to analyze approximately arbitrarily long paths. The path decomposition approach naturally captures the correlation of both link loads and link blocking events, Our algorithm represents a simple and computationally efficient solution to the difficult problem of computing call-blocking probabilities in wavelength-routing networks. We also demonstrate how our analytical techniques can be applied to gain insight into the problem of converter placement in wavelength-routing networks.

关键词： call-blocking probability converter placement decomposition algorithms wavelength-division multiplexing wavelength-routing networks

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：