检索结果-内蒙古大学图书馆

20th International Conference on High Performance Computing (HiPC)

作者： Langer, Akhil Venkataraman, Ramprasad Palekar, Udatta Kale, Laxmikant V. Univ Illinois Dept Comp Sci Urbana IL 61801 USA Univ Illinois Coll Business Urbana IL 61801 USA

ISBN: (纸本)9781479907298

Many real-world planning problems require searching for an optimal solution in the face of uncertain input. One approach to is to express them as a two-stage stochastic optimization problem where the search for an optimum in one stage is informed by the evaluation of multiple possible scenarios in the other stage. If integer solutions are required, then branch-and-bound techniques are the accepted norm. However, there has been little prior work in parallelizing and scaling branch-and-bound algorithms for stochastic optimization problems. In this paper, we explore the parallelization of a two-stage stochastic integer program solved using branch-and-bound. We present a range of factors that influence the parallel design for such problems. Unlike typical, iterative scientific applications, we encounter several interesting characteristics that make it challenging to realize a scalable design. We present two design variations that navigate some of these challenges. Our designs seek to increase the exposed parallelism while delegating sequential linear program solves to existing libraries. We evaluate the scalability of our designs using sample aircraft allocation problems for the US airfleet. It is important that these problems be solved quickly while evaluating large number of scenarios. Our attempts result in strong scaling to hundreds of cores for these datasets. We believe similar results are not common in literature, and that our experiences will feed usefully into further research on this topic.

关键词： Stochastic Integer branch-and-bound techniques optimal solution branch and bound algorithms Face

来源：评论

学校读者我要写书评

暂无评论

A mixed-integer linear program for optimizing sensor locations along freeway corridors

引用

TRANSPORTATION RESEARCH PART B-METHODOLOGICAL 2011年第1期45卷 208-217页

作者： Danczyk, Adam Liu, Henry X. Univ Minnesota Dept Civil Engn Minneapolis MN 55455 USA

How to optimally allocate limited freeway sensor resources is of great interest to transportation engineers. In this paper, we focus on the optimal allocation of point sensors, such as loop detectors, to minimize performance measurement errors. Although it has been shown that the minimization problem can be intuitively formulated as a nonlinear program, the formulation is so complex that only heuristic approaches can be used to solve the problem. In this paper, we transform the nonlinear program into an equivalent mixed-integer linear model. The linearized model is shown to have a graphical interpretation and can be solved using resource constrained shortest path algorithms. A customized branch-and-bound technique is then proposed to solve the resource constrained shortest path problem. Numerical experiments along an urban freeway corridor demonstrate that this sensor location model is successful in allocating loop detectors to improve the accuracy of travel time estimation. (C) 2010 Elsevier Ltd. All rights reserved.

关键词： Sensor location problem Mixed-integer linear program branch-and-bound techniques Loop detectors

来源：评论

学校读者我要写书评

暂无评论

ENERGY-LOSS REDUCTION BY CRITICAL SWITCHES

引用

IEEE TRANSACTIONS ON POWER DELIVERY 1993年第3期8卷 1246-1253页

作者： CHEN, CS CHO, MY DESA, JP Department of Electrical Engineering Sun Yat-Sen University Kaohsiung Taiwan

This paper presents a systematic method to derive an optimal switching plan to achieve energy loss minimization for short term and long term operation of distribution systems. The short term optimal switching criterion is developed by binary integer programming with branch and bound technique. A overall optimization problem is formulated for the optimal switching operation. It is further divided into several subproblems to find the largest energy loss reduction among all possible switching operation between two feeders. A quick method is applied to estimate the largest loss reduction for each feeder-pairs in the distribution system during short term switching operation. In this paper, the composite load profile of each feeder is derived by the field test over one year time period. According to the typical load patterns of each customer type, the hourly loading of each service section can be simulated more accurately. After determining the hourly optimal network configuration by taking into account the typical daily load patterns for all the distribution feeders, the long term optimal switching criterion for each season is derived and the corresponding critical switches, which should be operated for energy loss reduction as season changed from summer to winter and vice versa, are also determined. During the computer simulation, the installation and operation cost of sectionalizing switches are included in the objective function as actual cost so that the results obtained will be more practical. A practical Taipower distribution system is selected for computer simulation to demonstrate the efficiency and practicality of the proposed method to reduce the energy loss by operating the critical switches derived.

关键词： Optimal Integer Programming energy losses branch-and-bound techniques loss reduction short duration Feeders load profile dispensing system network configuration switching operation Switches

来源：评论

学校读者我要写书评

暂无评论

Lagrange duality and partitioning techniques in nonconvex global optimization

引用

JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS 1997年第2期95卷 347-369页

作者： Dur, M Horst, R Graduate Student Department of Mathematics University of Trier Trier Germany Professor Department of Mathematics University of Trier Trier Germany

It is shown that, for very general classes of nonconvex global optimization problems, the duality gap obtained by solving a corresponding Lagrangian dual in reduced to zero in the limit when combined with suitably refined partitioning of the feasible set. A similar result holds for partly convex problems where exhaustive partitioning is applied only in the space of nonconvex variables. Applications include branch-and-bound approaches for linearly constrained problems where convex envelopes can be computed, certain generalized bilinear problems, linearly constrained optimization of the sum of ratios of affine functions, and concave minimization under reverse convex constraints.

关键词： global optimization duality gap branch-and-bound techniques partly convex programs bilinear constraints sum of ratios reverse convex constraints

来源：评论

学校读者我要写书评

暂无评论

INDUSTRIAL LINEAR OPTIMIZATION PROBLEMS SOLVED BY CONSTRAINT LOGIC PROGRAMMING

引用

EUROPEAN JOURNAL OF OPERATIONAL RESEARCH 1995年第1期84卷 82-95页

作者： BISDORF, R LAURENT, S CTR RECH PUBL CTR UNIV162A AV FAIENCERIEL-1611 LUXEMBOURGLUXEMBOURG

In this article we try to illustrate that constraint logic programming (CLP) systems allow easy expression and solution of constrained decision problems. In order to do so, this paper proposes CLP solutions for two industrial linear optimization problems respectively using the Prolog III and the CHIP language. The first problem, a mixed linear multicriteria selection problem, illustrates the general linear rational solver. In order to fix some integer variables a branch and bound rounding heuristic is formulated. The second problem, a linear integer multicriteria location problem, is only concerned with integer finite domain variables and is particularly adapted to the CHIP system that provides a computation domain handling such variables.

关键词： CONSTRAINT LOGIC PROGRAMMING branch-and-bound techniques FINITE DOMAIN COMPUTATION LINEAR OPTIMIZATION GOAL-PROGRAMMING MULTICRITERIA SELECTION INDUSTRIAL DISPOSING PROBLEM INDUSTRIAL PRODUCTION SCHEDULING

来源：评论

学校读者我要写书评

暂无评论

Optimal Distributed Frequency Planning for OFDMA Femtocell Networks

Optimal Distributed Frequency Planning for OFDMA Femtocell N...

引用

IEEE 24th International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC)

作者： Rodrigues, Emanuel B. Casadevall, Fernando Univ Fed Ceara Wireless Telecommun Res Grp GTEL Fortaleza Ceara Brazil Univ Politecn Cataluna TSC Barcelona Spain

ISBN: (纸本)9781467362337

Femtocell networks have gained momentum due to their important benefits, such as improved indoor coverage, higher areal spectral efficiency, enhanced signal quality, among others. Those benefits are only achievable if adequate deployment decisions and efficient resource allocation techniques are able to assure the seamless co-existence among Femtocell Access Points (FAPs) within the femtocell tier and between FAPs and macrocell users. In this work, we study the frequency planning problem on the femtocell tier deployed on a closed access mode and using a dedicated spectrum. A novel radio resource allocation technique that performs a mid/long-term frequency planning for the FAPs in the femtocell tier is proposed. It is concluded in this paper that the Dynamic Frequency Planning (DFP) algorithm based on the branch and bound technique is able to find the optimal frequency planning according to any desired criterion and that the proposed algorithm is suitable for implementation in a distributed 4G femtocell network regarding signaling overhead and latency aspects.

关键词： frequency planning Femtocell networks Femtocells Resource utilization Signal quality branch-and-bound techniques

来源：评论

学校读者我要写书评

暂无评论

Optimal Control of Shading System using Hybrid Model Predictive Control 13

Optimal Control of Shading System using Hybrid Model Predict...

引用

13th European Control Conference (ECC)

作者： Le, Khang Bourdais, Romain Gueguen, Herve SUPELEC IETR Hybrid Syst Control Team F-35511 Cesson Sevigne France

ISBN: (纸本)9783952426913

This paper deals with the adaptation of a model predictive control to a blind system for building for preventing thermal discomfort, which occurs during summer. This system can be seen as a hybrid system by considering various blind positions. The MPC formulation leads to define a multi-objective optimization problem, for which the criteria are antagonist. This method seems to be effectiveness and is illustrated by various simulations within SIMBAD, a Matlab toolbox dedicated to building simulation. The proposed scheme is based on branch and bound techniques and does not rely on disturbance predictions, so that it could be easily implemented on industrial products.

关键词： Buildings Mathematical model Optimization Predictive models Temperature control Temperature measurement Visualization Buildings Temperature control temperature measurement Prediction models Mathematical Model Visualization Hybrid modes Optimal control Predictive control hybrid systems branch-and-bound techniques built structure Manufactured products

来源：评论

学校读者我要写书评

暂无评论

Optimization of timed automata models using mixed-integer programming

引用

1st International Workshop on Formal Modeling and Analysis of Timed Systems (FORMATS 2003)

作者： Panek, S Stursberg, O Engell, S Univ Dortmund BCI AST Proc Control Lab D-44221 Dortmund Germany

ISBN: (纸本)3540216715

Research on optimization of timed systems, as e.g. for computing optimal schedules of manufacturing processes, has lead to approaches that mainly fall into the following two categories: On one side, mixed integer programming (MIP) techniques have been developed to successfully solve scheduling problems of moderate to medium size. On the other side, reachability algorithms extended by the evaluation of performance criteria have been employed to optimize the behavior of systems modeled as timed automata (TA). While some successful applications to real-world examples have been reported for both approaches, industrial scale problems clearly call for more powerful techniques and tools. The work presented in this paper aims at combining the two types of approaches: The intention is to take advantage of the simplicity of modeling with timed automata (including modularity and synchronization), but also of the relaxation techniques and heuristics that axe known from MIP As a first step in this direction, the paper describes a translation procedure that automatically generates MIP representations of optimization problems formulated initially for TA. As a possible use of this translation, the paper suggests an iterative solution procedure, that combines a tree search for TA with the MIP solution of subproblems. The key idea is to use the relaxations in the MIP step to guide the tree search for TA in a branch-and-bound fashion.

关键词： branch-and-bound techniques discrete optimization mixed-integer programming scheduling timed automata

来源：评论

学校读者我要写书评

暂无评论

A Pricing Based Algorithm for Cell Switching Off in Green Cellular Networks

A Pricing Based Algorithm for Cell Switching Off in Green Ce...

引用

IEEE Vehicular Technology Conference

作者： Ali Yildiz Tolga Girici Halim Yanikomeroglu Department of Electrical and Electronics Engineering TOBB University of Economics and Technology Ankara Turkey 06561 Department of Systems and Computer Engineering Carleton University Ottawa Canada

ISBN: (纸本)9781467363365

In this study, we propose a pricing based algorithm that assigns user terminals (UTs) to base stations (BSs) and optimizes the transmission powers in a way that minimizes the energy expenditure. The algorithm takes into account the fixed energy expenditure that occurs even if a BS does not transmit to any UT, therefore the proposed algorithm switches off the unnecessary BSs in order to minimize the total energy expenditure. We compare this algorithm with two benchmarks. One of them is a simple algorithm that connects each UT to the BS with best channel conditions. Transmission powers are then optimized iteratively. The second benchmark is the optimal solution that is found using a branch and bound technique. The numerical evaluations reveal that the pricing based algorithm performs very close to the optimal.

关键词： branch bound technique optimal power transmission Energy Expenditure branches Cellular networks Optimal Bahamas Pricing UNIVERSAL TIME cell switching branch-and-bound techniques algorithms Cells

来源：评论

学校读者我要写书评

暂无评论

An Exact Dual Decomposition Algorithm for Shallow Semantic Parsing with Constraints 12

An Exact Dual Decomposition Algorithm for Shallow Semantic P...

引用

Joint Conference on Lexical and Computational Semantics

作者： Dipanjan Das Andre F. T. Martins Noah A. Smith Language Technologies Institute Carnegie Mellon University Pittsburgh PA 15213 USA Language Technologies Institute Carnegie Mellon University Pittsburgh PA 15213 USAInstitute de Telecomunicacoes Institute Superior Tecnico Lisboa Portugal

ISBN: (纸本)9781622765027

We present a novel technique for jointly predicting semantic arguments for lexical predicates. The task is to find the best matching between semantic roles and sentential spans, subject to structural constraints that come from expert linguistic knowledge (e.g., in the FrameNet lexicon). We formulate this task as an integer linear program (ILP); instead of using an off-the-shelf tool to solve the ILP, we employ a dual decomposition algorithm, which we adapt for exact decoding via a branch-and-bound technique. Compared to a baseline that makes local predictions, we achieve better argument identification scores and avoid all structural violations. Runtime is nine times faster than a proprietary ILP solver.

关键词： inductive logic programming Semantics Parsing Constraint Dual Exact decomposition branch-and-bound techniques Optimal matching

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：