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Optimal Integration of Departures and Arrivals in Terminal Airspace

JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2014年第1期37卷 207-213页

作者： Xue, Min Zelinski, Shannon Univ Calif Santa Cruz Univ Affiliated Res Ctr Moffett Field CA 94035 USA NASA Ames Res Ctr Aerosp High Dens Operat Branch Moffett Field CA 94035 USA

Coordination of operations with spatially and temporally shared resources, such as route segments, fixes, and runways, improves the efficiency of terminal airspace management. Problems in this category are, in general, computationally difficult compared with conventional scheduling problems. This paper presents a fast time algorithm formulation using a nondominated sorting genetic algorithm. It was first applied to a test problem introduced in existing literature. An experiment with a test problem showed that new methods can solve the 20 aircraft problem in fast time with a 65% or 440s delay reduction using shared departure fixes. To test its application in a more realistic and complicated problem, the nondominated sorting genetic algorithm was applied to a problem in Los Angeles terminal airspace, where interactions between 28% of Los Angeles arrivals and 10% of Los Angeles departures are resolved by spatial separation in current operations, which may introduce unnecessary delays. In this work, three types of separations (spatial, temporal, and hybrid separations) were formulated using the new algorithm. The hybrid separation combines both temporal and spatial separations. Results showed that, although temporal separation achieved less delay than spatial separation with a small uncertainty buffer, spatial separation outperformed temporal separation when the uncertainty buffer was increased. Hybrid separation introduced much less delay than both spatial and temporal approaches. For a total of 15 interacting departures and arrivals, when compared with spatial separation, the delay reduction of hybrid separation varied between 16% or 4.4min and 73% or 12.1min, corresponding to an uncertainty buffer from 0 to 60s. Furthermore, as a comparison with the nondominated sorting genetic algorithm, a first-come/first-serve-based heuristic method was implemented for the hybrid separation. Experiments showed that the results from the nondominated sorting genetic algorithm have 1

关键词： Airspace Management Genetic Algorithm Runways San Francisco International Airport Standard Terminal Arrival Route Standard Instrument Departure mixed integer linear programming Aircraft Speed Flight Altitude

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Region minimised monitor design for deadlock-prevention of S⁴PR nets

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IET CONTROL THEORY AND APPLICATIONS 2014年第13期8卷 1224-1237页

作者： Dong Lida Zhu Dan Zhu Chengcheng Xu Shanshan Hangzhou Normal Univ Hangzhou Inst Serv Engn Hangzhou Zhejiang Peoples R China Zhejiang Univ Dept Informat Sci & Elect Engn Hangzhou 310003 Zhejiang Peoples R China PLA Army Officer Acad Hefei Peoples R China

Constructing P-invariants is a typical way to design deadlock-prevention monitors for systems of sequential systems with shared resources ((SPR)-P-4) nets in the existing siphon-based methods. When there are some certain structures in (SPR)-P-4 nets, the existing siphon-based methods are not suitable for monitor designing. This study advances siphon's max-controlled conditions for P-invariant construction. Accordingly, a region minimised optimisation (RMO) method for deadlock-prevention monitor design is proposed, which is realised by using standardised mixed integer programming tool. In order to lower the limitation of monitors on system behaviour, the region under supervision is minimised. The RMO method is able to design monitors for (SPR)-P-4 nets in which the existing methods are not suitable, is free of trivial construction of P-invariants, and is applicable to (SPR)-P-4 nets with unobservable transitions. Since RMO is originated from the basic idea of siphon control, it remains the advantage of high computational efficiency, and also can replace the existing siphon-based monitor design methods.

关键词： COMPUTER monitors DEADLOCK prevention (Manufacturing) SIPHONS mixed integer linear programming RESEARCH INVARIANTS (Mathematics) DESIGN & construction

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Multi-objectives, multi-period optimization of district energy systems: I. Selection of typical operating periods

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COMPUTERS & CHEMICAL ENGINEERING 2014年 65卷 54-66页

作者： Fazlollahi, Samira Bungener, Stephane Laurent Mandel, Pierre Becker, Gwenaelle Marechal, Francois Veolia Environm Rech & Innovat F-78520 Limay France Ecole Polytech Fed Lausanne CH-1015 Lausanne Switzerland Veolia Environm Rech & Innovat F-78603 Maisons Laffitte France

The long term optimization of a district energy system is a computationally demanding task due to the large number of data points representing the energy demand profiles. In order to reduce the number of data points and therefore the computational load of the optimization model, this paper presents a systematic procedure to reduce a complete data set of the energy demand profiles into a limited number of typical periods, which adequately preserve significant characteristics of the yearly profiles. The proposed method is based on the use of a k- means clustering algorithm assisted byan is an element of- constraints optimization technique. The proposed typical periods allow us to achieve the accurate representation of the yearly consumption profiles, while significantly reducing the number of data points. The work goes one step further by breaking up each representative period into a smaller number of segments. This has the advantage of further reducing the complexity of the problem while respecting peak demands in order to properly size the system. Two case studies are discussed to demonstrate the proposed method. The results illustrate that a limited number of typical periods is sufficient to accurately represent an entire equipments' lifetime. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： Typical periods District energy systems mixed integer linear programming Evolutionary algorithm Multi-objective optimization Cluster analysis k-means algorithm

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Tactical Scheduling for Precision Air Traffic Operations: Past Research and Current Problems

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JOURNAL OF AEROSPACE INFORMATION SYSTEMS 2014年第4期11卷 234-256页

作者： Isaacson, D. R. Sadovsky, A. V. Davis, D. NASA Ames Res Ctr Moffett Field CA 94035 USA Univ Calif Los Angeles Los Angeles CA 90095 USA

An overview of current and future ATOs (air traffic operations) with a focus on congested air traffic operations near major airports was studied. The problem of scheduling and determining aircraft trajectories for PATOs (precision air traffic operations) was formulated with uncommonly close, but absolutely necessary, attention paid to the separation requirement. An air traffic controller directing aircraft to maintain a safe separation between aircraft of 5 n mile en route is providing a separation service to those aircraft. The pilot in command (PIC) is ultimately responsible for the operation of his/her aircraft and is responsible for seeing and avoiding other aircraft when weather conditions permit. While the route network provides a framework for organizing air traffic flows in congested airspace, sectorization of airspace is used to manage air traffic controller workload by limiting the number of aircraft that are being serviced and the scope of problems being managed by a single air traffic controller at any given time.

关键词： Air Route Traffic Control Center Airspace Region Communications, Navigation, Surveillance mixed integer linear programming GPS Applied Mathematics Optimal Control Aerospace Engineering Next Generation Air Transportation System NASA Ames Research Center

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Frequency optimization in public transportation systems: Formulation and metaheuristic approach

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EUROPEAN JOURNAL OF OPERATIONAL RESEARCH 2014年第1期236卷 27-36页

作者： Martinez, Hector Mauttone, Antonio Urquhart, Maria E. Univ Republica Dept Operat Res Montevideo Uruguay

We study the transit frequency optimization problem, which aims to determine the time interval between subsequent buses for a set of public transportation lines given by their itineraries, i.e., sequences of stops and street sections. The solution should satisfy a given origin-destination demand and a constraint on the available fleet of buses. We propose a new mixed integer linear programming (MILP) formulation for an already existing model, originally formulated as a nonlinear bilevel one. The proposed formulation is able to solve to optimality real small-sized instances of the problem using MILP techniques. For solving larger instances we propose a metaheuristic which accuracy is estimated by comparing against exact results (when possible). Both exact and approximated approaches are tested by using existing cases, including a real one related to a small-city which public transportation system comprises 13 lines. The magnitude of the improvement of that system obtained by applying the proposed methodologies, is comparable with the improvements reported in the literature, related to other real systems. Also, we investigate the applicability of the metaheuristic to a larger-sized real case, comprising more than 130 lines. (C) 2013 Elsevier B.V. All rights reserved.

关键词： Transportation Bus frequency optimization mixed integer linear programming Tabu Search

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Risk-Hedged Traffic Flow Management Under Airspace Capacity Uncertainties

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2014年第5期37卷 1487-1500页

作者： Sengupta, Prasenjit Tandale, Monish D. Menon, P. K. Optimal Synth Inc Los Altos CA 94022 USA

This paper presents a novel solution to the problem of air traffic flow management under airspace capacity uncertainty arising from weather or environmental effects. The traffic flow management problem is formulated as a stochastic linear program with multiple available routes between origin destination pairs, with the weather/environmental factors constraining the probable capacities along these routes. The performance index consists of the delays introduced by deterministic and stochastic capacity constraints. Primary impact of the weather/environmental factors is to require the rerouting of aircraft, causing additional delays. These additional delays require the aircraft to carry additional fuel or to incur costs associated with the failure to meet the schedules in hub-spoke operations. Thus, the variance of delays can be used to define the degree of risk in stochastic traffic flow management, and flow management algorithms that assure the variations in the delay below a specified value can be considered as providing a hedge against uncertain weather or environmental factors. The algorithm developed in this paper produces a risk-hedged decision that results in the least delay at a specified level of acceptable variance. This algorithm represents a dramatic departure from the more traditional stochastic traffic flow management algorithms, which minimize expected value of delays, without attempting to control their variances. The performance of the present stochastic traffic flow management algorithm is demonstrated on a use case representing National Airspace System operations on a regional scale.

关键词： Airspace Air Traffic Flow Management Air Route Traffic Control Center Dantzig Wolfe Decomposition Detroit Metropolitan Wayne County Airport Probability Distribution National Oceanic and Atmospheric Administration Graphics Processing Unit Coded Instrument Flight Procedures mixed integer linear programming

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Design and Optimization of Capacitated Supply Chain Networks Including Quality Measures

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MATHEMATICAL PROBLEMS IN ENGINEERING 2014年第1期2014卷 1-17页

作者： Castillo-Villar, Krystel K. Smith, Neale R. Herbert-Acero, Jose F. Univ Texas San Antonio Dept Mech Engn San Antonio TX 78249 USA Inst Tecnol & Estudios Super Monterrey Qual & Mfg Ctr Monterrey 64849 NL Mexico Inst Tecnol & Estudios Super Monterrey Dept Phys San Antonio TX 78249 USA

This paper presents (1) a novel capacitated model for supply chain network design which considers manufacturing, distribution, and quality costs (named SCND-COQ model) and (2) five combinatorial optimization methods, based on nonlinear optimization, heuristic, and metaheuristic approaches, which are used to solve realistic instances of practical size. The SCND-COQ model is a mixed-integer nonlinear problem which can be used at a strategic planning level to design a supply chain network that maximizes the total profit subject to meeting an overall quality level of the final product at minimum costs. The SCND-COQ model computes the quality-related costs for the whole supply chain network considering the interdependencies among business entities. The effectiveness of the proposed solution approaches is shown using numerical experiments. These methods allow solving more realistic (capacitated) supply chain network design problems including quality-related costs (inspections, rework, opportunity costs, and others) within a reasonable computational time.

关键词： SUPPLY chains MATHEMATICAL optimization QUALITY assurance HEURISTIC algorithms mixed integer linear programming

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Fair cost distribution among smart homes with microgrid

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ENERGY CONVERSION AND MANAGEMENT 2014年 80卷 498-508页

作者： Zhang, Di Liu, Songsong Papageorgiou, Lazaros G. UCL Ctr Proc Syst Engn Dept Chem Engn London WC1E 7JE England

Microgrid is composed of a set of distributed energy resources (DER) and is considered as an alternative energy providing system to the current centralised energy generation. Smart homes equipped with smart grid technology, such as smart meter and communication system, are becoming popular for their lower energy cost and provision of comfort. Flexible energy-consuming household tasks can be scheduled coordinately among multiple homes which share the common microgrid. When local DERs cannot fulfill the whole demand, smart homes will compete with each other to obtain energy from local DERs and achieve their respective lowest energy cost. In this paper, a mathematical programming formulation is presented for the fair cost distribution among smart homes with microgrid. The proposed model is based on the lexicographic minimax method using a mixed integer linear programming (MILP) approach. One-day forecasted energy cost of each smart home is minimised under fairness concern. DER operation, DER output sharing among smart homes and electricity consumption household tasks are scheduled. Two numerical examples with 10 and 50 smart homes are studied. The computational results illustrate that the proposed approach can obtain obvious cost savings (30% and 24% respectively) and fair cost distribution among multiple homes under given fairness scenario. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： Lexicographic minimax method Fair planning/scheduling Smart homes Microgrid mixed integer linear programming Real-time pricing

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Sustainable reverse logistics network design for household plastic waste

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FLEXIBLE SERVICES AND MANUFACTURING JOURNAL 2014年第1-2期26卷 119-142页

作者： Bing, Xiaoyun Bloemhof-Ruwaard, Jacqueline M. van der Vorst, Jack G. A. J. Wageningen Univ Operat Res & Logist Grp NL-6700 AP Wageningen Netherlands Top Inst Food & Nutr Wageningen Netherlands

Plastic recycling is a legal requirement and can yield environmental benefits. In the Netherlands, there is a complex network of various collection methods, separation centers, sorting centers and reprocessors. The first step of the recycling system, separating plastics from other waste, can occur within households (source-separation) or in separation centers (post-separation), making a difference in collection channel choice and technology requirements. The purpose of this paper is to provide decision support on choosing the most suitable combination of separation methods in the Netherlands. Decision support is given through optimized reverse logistics network design which makes the overall recycling system more efficient and sustainable, while taking into account the interests of various stakeholders (municipalities, households, etc.). A mixed integer linear programming (MILP) model, which minimizes both transportation cost and environmental impact, is used in this network design. The research follows the approach of scenario study;the baseline scenario is the current situation and other scenarios are designed with various strategic alternatives. Modeling is conducted by using a graphical optimization tool IBM LogicNet Plus 7.1. Comparing these scenarios, the results show that the current network settings of the baseline situation is efficient in logistics terms but has a potential to adapt to strategic changes, depending on the assumptions regarding availability of the required processing facilities to treat plastic waste. In some of the tested scenarios, a separate collection channel for Polyethylene Terephthalate (PET) bottles is cost efficient and saves carbon emission. Although the figures differ depending on the separation method choices of municipalities, our modeling result of all the tested scenarios shows a saving of more than 25 % carbon emission compared to the current network.

关键词： mixed integer linear programming Sustainability Network Plastics Household waste Reverse logistics

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Hybrid simulation and MIP based heuristic algorithm for the production and distribution planning in the soft drink industry

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JOURNAL OF MANUFACTURING SYSTEMS 2014年第3期33卷 385-399页

作者： Sel, Cagri Bilgen, Bilge Dokuz Eylul Univ Dept Ind Engn TR-35160 Izmir Turkey

This study addresses the production and distribution planning problem in the soft drink industry. The problem involves the allocation of production volumes among the different production lines in the manufacturing plants, and the delivery of products to the distribution centers (DCs). A mixed integer linear programming (MILP) model is developed for the problem. In this paper, we present a hybrid solution methodology combining simulation and mixed integer programming (MIP) based Fixed and Optimize heuristic to solve the considered problem. First, MIP based Fix and Relax (F&R), Fix and Optimize (F&O) heuristics are proposed. The solution quality and performance of the proposed heuristics are analyzed with the randomly generated demand figures for the three granularity categories and various capacity load scenarios. Computational performances of these heuristic procedures are compared with the standard MIP results. The computational experiments carried out on a large set of instances have shown that the F&O heuristic algorithm provides good quality solutions in a reasonable amount of time. Second, simulation model is introduced to represent the problem with stochastic machine failures. Hybrid methodology combining the MIP based F&O heuristic and simulation model is implemented. The optimization model uses an F&O heuristic to determine the production and delivered quantity. Subsequently the simulation model is applied to capture the uncertainty in the production rate. Numerical studies from the data which have a tight production capacity and high demand granularity demonstrate that the developed hybrid approach is capable of solving real sized instance within a reasonable amount of time and demonstrate the applicability of the proposed approach. (C) 2014 The Society of Manufacturing Engineers. Published by Elsevier Ltd. All rights reserved.

关键词： Supply chain management Production and distribution planning mixed integer linear programming Hybrid approach Simulation Rolling horizon heuristics

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