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Logistics system design for biomass-to-bioenergy industry with multiple types of feedstocks

BIORESOURCE TECHNOLOGY 2011年第23期102卷 10936-10945页

作者： Zhu, Xiaoyan Yao, Qingzhu Univ Tennessee Dept Ind & Informat Engn Knoxville TN 37996 USA Revenue Analyt Inc Atlanta GA 30339 USA

It is technologically possible for a biorefinery to use a variety of biomass as feedstock including native perennial grasses (e.g., switchgrass) and agricultural residues (e.g., corn stalk and wheat straw). Incorporating the distinct characteristics of various types of biomass feedstocks and taking into account their interaction in supplying the bioenergy production, this paper proposed a multi-commodity network flow model to design the logistics system for a multiple-feedstock biomass-to-bioenergy industry. The model was formulated as a mixed integer linear programming, determining the locations of warehouses, the size of harvesting team, the types and amounts of biomass harvested/purchased, stored, and processed in each month, the transportation of biomass in the system, and so on. This paper demonstrated the advantages of using multiple types of biomass feedstocks by comparing with the case of using a single feedstock (switchgrass) and analyzed the relationship of the supply capacity of biomass feedstocks to the output and cost of biofuel. (C) 2011 Elsevier Ltd. All rights reserved.

关键词： Multiple feedstocks Biomass Bioenergy Supply chain mixed integer linear programming

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Optical multicast provisioning with differentiated leaf availability guarantee in WDM networks

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PHOTONIC NETWORK COMMUNICATIONS 2011年第1期21卷 21-27页

作者： Zhang, Chunlei Lanzhou Jiaotong Univ Sch Elect & Informat Engn Lanzhou 730070 Ganzu Peoples R China

As multicast applications become more and more popular, implementing multicast in the optical domain has attracted increased attention due to its more efficient bandwidth usage. And also these services have quality-of-service requirements. In this article, the problem of cost-effective optical multicast provisioning to satisfy the differentiated leaf availability requirements is formally stated. A mixed integer linear Program formulation is proposed for provisioning dedicated light-tree protection with differentiated leaf availability guarantee. The algorithm is so complex and infeasible that we also propose a feasible two-step approximate approach to solve the problem. Different from the previous schemes, our scheme finds out the primary light-trees and backup paths for destination nodes whose availability is not satisfied. Because of taking the different leaf availability requirements into account, the proposed algorithm obtains a more efficient feasible solution requiring less network resources.

关键词： Optical multicast Availability mixed integer linear programming

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Link Transmission Model for Air Traffic Flow Management

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2011年第5期34卷 1342-1351页

作者： Cao, Yi Sun, Dengfeng Purdue Univ Sch Aeronaut & Astronaut W Lafayette IN 47906 USA

Optimization of air traffic flow in the National Airspace System is, by nature, a large-scale problem, the solving of which usually requires intensive computation. This paper presents a mixed integer linear programming method to solve a nationwide air traffic flow management problem based on an aggregate air traffic model. A dual decomposition method is applied to solve the large-scale traffic management problem, where the nationwide problem is decomposed path by path into 1000s of subproblems that are solved independently. It is shown in this paper that the solution with the dual decomposition method converges to the global optimum. The major contribution of the proposed modeling and optimization framework is that it is about 6 times faster than a previously developed large-capacity cell transmission model. It is also shown that the proposed optimization method obtains an equally optimal solution as the large-capacity cell transmission model. In the meantime, the proposed model is capable of including both ground delay and airborne delay, while the large-capacity cell transmission model includes airborne delay only. The traffic forecasting capability of the new model is also examined statistically at the sector level and the national level. It is shown that the sector counts are predicted with relative errors of less than 20% for over 80% of the high-altitude sectors in the United States. Further analysis also suggests that the accuracy of the proposed model is comparable with the other two aggregate models in the literature.

关键词： Air Traffic Flow Management Aircraft Situation Display to Industry Airspace Airborne Aircraft Next Generation Air Transportation System mixed integer linear programming linear programming Cost Control Flight Planning Airway

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A discrete colonial competitive algorithm for hybrid flowshop scheduling to minimize earliness and quadratic tardiness penalties

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EXPERT SYSTEMS WITH APPLICATIONS 2011年第12期38卷 14490-14498页

作者： Behnamian, J. Zandieh, M. Shahid Beheshti Univ Management & Accounting Fac Dept Ind Management GC Tehran Iran Amirkabir Univ Technol Dept Ind Engn Tehran Iran

Recently introduced colonial competitive algorithm (CCA) has shown its excellent capability on different optimization problems. The aim of this paper is to propose a discrete version of this method to determine a schedule that minimizes sum of the linear earliness and quadratic tardiness in the hybrid flowshops scheduling problem with simultaneously considering effects of sequence-dependent setup times and limited waiting time. In other word we assume that the waiting time for each job between two consecutive stages cannot be greater than a given upper bound. Also for this problem, a mixed integer program is formulated. Computational results are presented to evaluate the performance of the proposed algorithms for problems with different structures. (C) 2011 Elsevier Ltd. All rights reserved.

关键词： Hybrid flowshops scheduling Limited waiting time Colonial competitive algorithm mixed integer linear programming Earliness and tardiness penalties

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A heuristic approach to long-range production planning of cement quarry operations

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PRODUCTION PLANNING & CONTROL 2011年第4期22卷 353-364页

作者： Asad, Mohammad Waqar Ali NWFP Univ Engn & Technol Dept Min Engn Peshawar 25000 Pakistan

Cement manufacturing requires sustained supply of raw materials from limestone quarry. Raw materials inventory in limestone quarry is identified as a block model, usually, consisting of thousands of blocks. Each block consists of a distinct amount of chemical constituents which are vital for cement production. An individual block never satisfies the process quality constraints;therefore, the blending of various quarry blocks with expensive additives purchased from the market becomes a prerequisite. The objective of a quarry production scheduling model is to mine available blocks in a sequence such that cement plant quantity and quality requirements are satisfied. Achieving a solution to the problem, where each block is defined as an integer (0-1) variable, often within reasonable time, has been a challenge for the mining industry. In this article, the complex production scheduling problem is divided into two sub-problems, where quarry sequencing algorithm develops feasible quarry plans and mixed integer linear programming based blending formulation minimises cost by selecting a plan that requires least amount of additives from the market. The implementation of methodology on an existing operation ensures time as well as cost savings compared to the schedules produced manually.

关键词： production scheduling mixed integer linear programming raw materials blending cement/mining industry

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Global supply chain planning for pharmaceuticals

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CHEMICAL ENGINEERING RESEARCH & DESIGN 2011年第11A期89卷 2396-2409页

作者： Sousa, Rui T. Liu, Songsong Papageorgiou, Lazaros G. Shah, Nilay Univ London Imperial Coll Sci Technol & Med Ctr Proc Syst Engn London SW7 2AZ England UCL Ctr Proc Syst Engn Dept Chem Engn London WC1E 7JE England

The shortening of patent life periods, generic competition and public health policies, among other factors, have changed the operating context of the pharmaceutical industry. In this work we address a dynamic allocation/planning problem that optimises the global supply chain planning of a pharmaceutical company, from production stages at primary and secondary sites to product distribution to markets. The model explores different production and distribution costs and tax rates at different locations in order to maximise the company's net profit value (NPV). Large instances of the model are not solvable in realistic time scales, so two decomposition algorithms were developed. In the first method, the supply chain is decomposed into independent primary and secondary subproblems, and each of them is optimised separately. The second algorithm is a temporal decomposition, where the main problem is separated into several independent subproblems, one per each time period. These algorithms enable the solution of large instances of the problem in reasonable time with good quality results. (C) 2011 Published by Elsevier B.V. on behalf of The Institution of Chemical Engineers.

关键词： Global supply chain Pharmaceuticals mixed integer linear programming Large-scale optimisation Decomposition algorithm

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Fault-tolerant control allocation for Mars entry vehicle using adaptive control

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INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING 2011年第2期25卷 95-113页

作者： Marwaha, Monika Valasek, John Texas A&M Univ Dept Aerosp Engn Vehicle Syst & Control Lab College Stn TX 77843 USA

Accurate and reliable control of planetary entry is a major challenge for planetary exploration vehicles. For Mars entry, uncertainties in atmospheric properties such as winds aloft and density pose a major problem for meeting precision landing requirements. Anticipated manned missions to Mars will also require levels of safety and fault tolerance not required during earlier robotic missions. This paper develops a nonlinear fault-tolerant controller specifically tailored for addressing the unique environmental and mission demands of future Mars entry vehicles. The controller tracks a desired trajectory from entry interface to parachute deployment, and has an adaptation mechanism that reduces tracking errors in the presence of uncertain parameters such as atmospheric density, and vehicle properties such as aerodynamic coefficients and inertias. This nonlinear control law generates the commanded moments for a discrete control allocation algorithm, which then generates the optimal controls required to follow the desired trajectory. The reaction control system acts as a non-uniform quantizer, which generates applied moments that approximate the desired moments generated by a continuous adaptive control law. If a fault is detected in the control jets, it reconfigures the controls and minimizes the impact of control failures or damage on trajectory tracking. It is assumed that a fault identification and isolation scheme already exists to identify failures. A stability analysis is presented, and fault tolerance performance is evaluated with non real-time simulation for a complete Mars entry trajectory tracking scenario using various scenarios of control effector failures. The results presented in the paper demonstrate that the control algorithm has a satisfactory performance for tracking a pre-defined trajectory in the presence of control failures, in addition to plant and environment uncertainties. Copyright (C) 2010 John Wiley & Sons, Ltd.

关键词： nonlinear adaptive control fault tolerant discrete control allocation mixed integer linear programming entry vehicle

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Application of Fuzzy Multi-Objective linear programming Model in a Multi-Period Multi-Product Production Planning Problem

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INTERNATIONAL JOURNAL OF COMPUTATIONAL INTELLIGENCE SYSTEMS 2011年第2期4卷 228-243页

作者： Taghizadeh, Kaveh Bagherpour, Morteza Mahdavi, Iraj Mazandaran Univ Sci & Technol Dept Ind Engn Babol Sar Iran Iran Univ Sci & Technol Dept Ind Engn Tehran Iran

The Multi-Period Multi-Product (MPMP) production planning, as a well known problem in literature, attempts to match production rates of individual products with fluctuated market demand over planning horizon. This study, demonstrates how the conventional MPMP linear programming (LP) model may fail to utilize available capacity of machines, and also a novel Multi Objective linear programming (MOLP) model is developed to simultaneously minimize net present value of production costs and maximize machine utilization. The proposed model consists of production constraints such as available labor, inventory, maximum subcontracting levels and also forecasted demands. The proposed MOLP model is further converted to a Fuzzy Multi Objective linear programming (FMOLP) model utilizing piecewise linear membership functions. The model, accommodates the Decision Maker (DM) with a more systematic decision making approach enabling the DM to adjust the search direction during the solving procedure to achieve the most satisfactory result.

关键词： Multi-Period Multi-Product production planning Aggregate production planning Fuzzy Multi-Objective linear programming Piecewise linear membership functions mixed integer linear programming

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The MIND method: A decision support for optimization of industrial energy systems - Principles and case studies

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APPLIED ENERGY 2011年第3期88卷 577-589页

作者： Karlsson, Magnus Linkoping Univ Dept Management & Engn Div Energy Syst SE-58183 Linkoping Sweden

Changes in complex industrial energy systems require adequate tools to be evaluated satisfactorily. The MIND method (Method for analysis of INDustrial energy systems) is a flexible method constructed as decision support for different types of analyses of industrial energy systems. It is based on mixed integer linear programming (MILP) and developed at Linkoping University in Sweden. Several industries, ranging from the food industry to the pulp and paper industry, have hitherto been modelled and analyzed using the MIND method. In this paper the principles regarding the use of the method and the creation of constraints of the modelled system are presented. Two case studies are also included, a dairy and a pulp and paper mill, that focus some measures that can be evaluated using the MIND method, e.g. load shaping, fuel conversion and introduction of energy efficiency measures. The case studies illustrate the use of the method and its strengths and weaknesses. The results from the case studies are related to the main issues stated by the European Commission, such as reduction of greenhouse gas emissions, improvements regarding security of supply and increased use of renewable energy, and show great potential as regards both cost reductions and possible load shifting. (C) 2010 Elsevier Ltd. All rights reserved.

关键词： Decision support systems mixed integer linear programming Energy efficiency Industrial energy systems Load shaping Optimization Modelling European Commission 20-20-20 Objectives

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Discrete and continuous time representations and mathematical models for large production scheduling problems: A case study from the pharmaceutical industry

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EUROPEAN JOURNAL OF OPERATIONAL RESEARCH 2011年第2期215卷 383-392页

作者： Stefansson, Hlynur Sigmarsdottir, Sigrun Jensson, Pall Shah, Nilay Reykjavik Univ Sch Sci & Engn Reykjavik Iceland Univ Iceland Fac Engn Reykjavik Iceland Univ London Imperial Coll Sci Technol & Med Dept Chem Engn Ctr Proc Syst Engn London SW7 2AZ England

The underlying time framework used is one of the major differences in the basic structure of mathematical programming formulations used for production scheduling problems. The models are either based on continuous or discrete time representations. In the literature there is no general agreement on which is better or more suitable for different types of production or business environments. In this paper we study a large real-world scheduling problem from a pharmaceutical company. The problem is at least NP-hard and cannot be solved with standard solution methods. We therefore decompose the problem into two parts and compare discrete and continuous time representations for solving the individual parts. Our results show pros and cons of each model. The continuous formulation can be used to solve larger test cases and it is also more accurate for the problem under consideration. (C) 2011 Elsevier B.V. All rights reserved.

关键词： Production Scheduling mixed integer linear programming Time representations

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