检索结果-内蒙古大学图书馆

Scheduling open shops with parallel machines to minimize total completion time

JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS 2011年第5期235卷 1275-1287页

作者： Naderi, B. Ghomi, S. M. T. Fatemi Aminnayeri, M. Zandieh, M. Amirkabir Univ Technol Dept Ind Engn Tehran Iran Shahid Beheshti Univ GC Accounting & Management Fac Dept Ind Management Tehran Iran

This paper explores scheduling a realistic variant of open shops with parallel machines per working stage. Since real production floors seldom employ a single machine for each operation, the regular open shop problem is very often in practice extended with a set of parallel machines at each stage. The purpose of duplicating machines in parallel is to either eliminate or to reduce the impact of bottleneck stages on the overall shop efficiency. The objective is to find the sequence which minimizes total completion times of jobs. We first formulate the problem as an effective mixed integer linear programming model, and then we employ memetic algorithms to solve the problem. We employ Taguchi method to evaluate the effects of different operators and parameters on the performance of memetic algorithm. To further enhance the memetic algorithm, we hybridize it with a simple form of simulated annealing as its local search engine. To assess the performance of the model and algorithms, we establish two computational experiments. The first one is small-sized instances by which the model and general performance of the algorithms are evaluated. The second one consists of large-sized instances by which we further evaluate the algorithms. (C) 2010 Elsevier B.V. All rights reserved.

关键词： Scheduling Open shop Parallel machines Mathematical model mixed integer linear programming Memetic algorithm Taguchi method

来源：评论

学校读者我要写书评

暂无评论

Challenges and models in supporting logistics system design for dedicated-biomass-based bioenergy industry

引用

BIORESOURCE TECHNOLOGY 2011年第2期102卷 1344-1351页

作者： Zhu, Xiaoyan Li, Xueping Yao, Qingzhu Chen, Yuerong Univ Tennessee Dept Ind & Informat Engn Knoxville TN 37996 USA Univ Akron Dept Mech Engn Akron OH 44325 USA

This paper analyzed the uniqueness and challenges in designing the logistics system for dedicated biomass-to-bioenergy industry, which differs from the other industries, due to the unique features of dedicated biomass (e.g., switchgrass) including its low bulk density, restrictions on harvesting season and frequency, content variation with time and circumambient conditions, weather effects, scattered distribution over a wide geographical area, and so on. To design it, this paper proposed a mixed integer linear programming model. It covered from planting and harvesting switchgrass to delivering to a biorefinery and included the residue handling, concentrating on integrating strategic decisions on the supply chain design and tactical decisions on the annual operation schedules. The present numerical examples verified the model and demonstrated its use in practice. This paper showed that the operations of the logistics system were significantly different for harvesting and non-harvesting seasons, and that under the well-designed biomass logistics system, the mass production with a steady and sufficient supply of biomass can increase the unit profit of bioenergy. The analytical model and practical methodology proposed in this paper will help realize the commercial production in biomass-to-bioenergy industry. (C) 2010 Elsevier Ltd. All rights reserved.

关键词： Logistics analysis Switchgrass Biomass-to-bioenergy Supply chain mixed integer linear programming

来源：评论

学校读者我要写书评

暂无评论

On electrical load tracking scheduling for a steel plant

引用

COMPUTERS & CHEMICAL ENGINEERING 2011年第12期35卷 3044-3047页

作者： Hait, Alain Artigues, Christian Univ Toulouse Inst Super Aeronaut & Espace F-31055 Toulouse France CNRS LAAS F-31077 Toulouse 4 France Univ Toulouse UPS INSA INPISAEUT1UTMLAAS F-31077 Toulouse 4 France

Nolde and Morari (2010) study a steel manufacturing scheduling problem where the tasks must be scheduled such that electricity consumption matches to a pre-specified periodic energy chart. They propose a continuous time integer linear programming formulation to solve the problem. In this note, we present an alternative continuous time formulation, focused on the relative positions of tasks and time periods, that improves significantly the computation time. (C) 2011 Elsevier Ltd. All rights reserved.

关键词： Steel plant mixed integer linear programming Load tracking

来源：评论

学校读者我要写书评

暂无评论

Optimal design and global sensitivity analysis of biomass supply chain networks for biofuels under uncertainty

引用

COMPUTERS & CHEMICAL ENGINEERING 2011年第9期35卷 1738-1751页

作者： Kim, Jinkyung Realff, Matthew J. Lee, Jay H. Georgia Inst Technol Sch Chem & Biomol Engn Atlanta GA 30332 USA Korea Adv Inst Sci & Technol Dept Chem & Biomol Engn Taejon 305701 South Korea

Bio-fuels represent promising candidates for renewable liquid fuels. One of the challenges for the emerging industry is the high level of uncertainty in supply amounts, market demands, market prices, and processing technologies. These uncertainties complicate the assessment of investment decisions. This paper presents a model for the optimal design of biomass supply chain networks under uncertainty. The uncertainties manifest themselves as a large number of stochastic model parameters that could impact the overall profitability and design. The supply chain network we study covers the Southeastern region of the United States and includes biomass supply locations and amounts, candidate sites and capacities for two kinds of fuel conversion processing, and the logistics of transportation from the locations of forestry resources to the conversion sites and then to the final markets. To reduce the design problem to a manageable size the impact of each uncertain parameter on the objective function is computed for each end of the parameter's range. The parameters that cause the most change in the profit over their range are then combined into scenarios that are used to find a design through a two stage mixed integer stochastic program. The first stage decisions are the capital investment decisions including the size and location of the processing plants. The second stage recourse decisions are the biomass and product flows in each scenario. The objective is the maximization of the expected profit over the different scenarios. The robustness and global sensitivity analysis of the nominal design (for a single nominal scenario) vs. the robust design (for multiple scenarios) are analyzed using Monte Carlo simulation over the hypercube formed from the parameter ranges. (C) 2011 Elsevier Ltd. All rights reserved.

关键词： Biorefinery Supply chain networks Uncertainty Robustness mixed integer linear programming Global sensitivity analysis

来源：评论

学校读者我要写书评

暂无评论

An integer-valued data envelopment analysis model with bounded outputs

引用

INTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH 2011年第6期18卷 741-749页

作者： Matin, Reza Kazemi Emrouznejad, Ali Islamic Azad Univ Dept Math Karaj Branch Karj Iran Aston Univ Aston Business Sch Birmingham B4 7ET W Midlands England

integer-valued data envelopment analysis (DEA) with alternative returns to scale technology has been introduced and developed recently by Kuosmanen and Kazemi Matin. The proportionality assumption of their introduced "natural augmentability" axiom in constant and nondecreasing returns to scale technologies makes it possible to achieve feasible decision-making units (DMUs) of arbitrary large size. In many real world applications it is not possible to achieve such production plans since some of the input and output variables are bounded above. In this paper, we extend the axiomatic foundation of integer-valued DEA models for including bounded output variables. Some model variants are achieved by introducing a new axiom of "boundedness" over the selected output variables. A mixed integer linear programming (MILP) formulation is also introduced for computing efficiency scores in the associated production set.

关键词： data envelopment analysis integer-valued DEA efficiency mixed integer linear programming bounded outputs

来源：评论

学校读者我要写书评

暂无评论

Joint Metering and Conflict Resolution in Air Traffic Control

引用

JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2011年第5期34卷 1507-1518页

作者： Le Ny, Jerome Pappas, George J. Univ Penn Dept Elect & Syst Engn Philadelphia PA 19104 USA

This paper describes a novel optimization-based approach to conflict resolution in air traffic control, based on geometric programming. A key feature of this approach is its ability to also take into account various metering directives issued by the traffic flow management level, in contrast to most methods that focus purely on aircraft separation issues. Moreover, the proposed methodology can account for some of the nonlinearities present in the formulations of conflict resolution Problems, while incurring only a small penalty in computation time with respect to the fastest linear-programming-based approaches. integer variables can be introduced to improve the quality of the solutions and to include combinatorial choices, for example, to optimize over aircraft sequences in merging streams. Simulation results demonstrate the efficiency of the approach on various aircraft separation problems, including miles-in-trail and minutes-in-trail restrictions through airspace fixes and boundaries.

关键词： Air Traffic Controller Traffic Flow Management Airspace linear programming mixed integer linear programming Conflict Detection and Resolution Path Planning Airborne Aircraft Branch and Bound Algorithm Automated Decision Support

来源：评论

学校读者我要写书评

暂无评论

Redispatching Active and Reactive Powers Using a Limited Number of Control Actions

引用

IEEE TRANSACTIONS ON POWER SYSTEMS 2011年第3期26卷 1221-1230页

作者： Capitanescu, Florin Wehenkel, Louis Univ Liege Dept Elect Engn & Comp Sci B-4000 Liege Belgium

This paper deals with some essential open questions in the field of optimal power flow (OPF) computations, namely: the limitation of the number of controls allowed to move, the trade-off between the objective function and the number of controls allowed to move, the computation of the minimum number of control actions needed to satisfy constraints, and the determination of the sequence of control actions to be taken by the system operator in order to achieve its operation goal. To address these questions, we propose approaches which rely on the computation of sensitivities of the objective function and inequality constraints with respect to control actions. We thus determine a subset of controls allowed to move in the OPF, by solving a sensitivity-based mixed integer linear programming (MILP) problem. We study the performances of these approaches on three test systems (of 60, 118, and 618 buses) and by considering three different OPF problems important for a system operator in emergency and/or in normal states, namely the removal of thermal congestions, the removal of bus voltage limits violation, and the reduction of the active power losses.

关键词： mixed integer linear programming nonlinear programming optimal power flow

来源：评论

学校读者我要写书评

暂无评论

Comparison of just-in-time and time window delivery policies for a single-item capacitated lot sizing problem

引用

INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH 2011年第9期49卷 2567-2585页

作者： Akbalik, Ayse Penz, Bernard Univ Grenoble G SCOP F-38031 Grenoble 1 France TOBB Univ Econ & Technol Dept Ind Engn TR-06560 Sogutozu Turkey

In this article, a comparative discussion between just-in-time (JIT) and time window (TW) policies is performed for a special case of the single-item capacitated lot sizing problem (CLSP), in which two storage levels are available, including plant and customer levels. In the JIT policy, the customer demand has to be satisfied on the due date of the demand, however, in the TW policy, the shipment can be made a few days before the due date. The influence of the two policies on the total cost is studied for a structure of a single capacitated plant which replenishes a customer, both having storage spaces. Both planning problems are shown to be NP-hard using the well-known CLSP which constitutes their subpart. A mixed integer linear program and a pseudo-polynomial dynamic program are proposed for each policy. The objective of this article is first to solve the TW problem to the optimality and, second to show the gain obtained by TW policy in terms of cost reduction. For the benchmark, we used a large data set to see the influence of different parameters on the total cost.

关键词： lot sizing delivery policies time window dynamic programming mixed integer linear programming

来源：评论

学校读者我要写书评

暂无评论

MILP model for emergy optimization in EIP water networks

引用

CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY 2011年第5期13卷 703-712页

作者： Taskhiri, Mohammad Sadegh Tan, Raymond R. Chiu, Anthony S. F. De La Salle Univ Ctr Engn & Sustainable Dev Res Manila Philippines De La Salle Univ Dept Ind Engn Manila Philippines

The eco-industrial park (EIP) concept provides a framework in which several plants can cooperate with each other and exchange their wastewater to minimize total freshwater consumption. Emergy analysis is a methodology that considers the total, cumulative energy which has been consumed within a system;thus, by minimizing emergy, an environmentally optimal EIP can be designed. This article presents a mixed-integer linear programming (MILP) model for minimizing emergy of an interplant water network in an EIP. The methodology accounts for the environmental impacts of water use, energy consumption, and capital goods within the EIP in a balanced manner. The proposed technique is then demonstrated by solving a case study from literature.

关键词： Emergy Eco-industrial park mixed integer linear programming Water reuse network

来源：评论

学校读者我要写书评

暂无评论

Modeling the machine configuration and line-balancing problem of a PCB assembly line with modular placement machines

引用

INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2011年第1-4期54卷 349-360页

作者： Rong, Aiying Toth, Attila Nevalainen, Olli S. Knuutila, Timo Lahdelma, Risto Univ Turku Dept Informat Technol Turku 20014 Finland Univ Turku TUCS Turku 20014 Finland Univ Szeged Juhasz Gyula Fac Educ Szeged Hungary Aalto Univ Dept Energy Technol Aalto 00076 Finland

This paper studies the combined task of determining a favorable machine configuration and line balancing (MCLB) for an assembly line where a single type of printed circuit board is assembled by a set of interconnected, reconfigurable machine modules. The MCLB problem has been solved previously by heuristic methods. In the present work, we give a mathematical formulation for it and transform the model into a linear integer programming model that can be solved using a standard solver for problems of moderate size. The model determines the best machine configuration and allocation of components to the machine modules with the objective of minimizing the cycle time. Because the solutions found in this way are globally optimal, they can be used to evaluate the efficiency of previous heuristics designed for the MCLB problem. In our experiments, an evolutionary algorithm gave near optimal results.

关键词： Printed circuit board assembly Reconfigurable machine modules Line balancing integer programming mixed integer linear programming

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：