New environmental regulations have driven companies to adopt low-carbon manufacturing. This research is aimed at considering carbon dioxide in the operational decision level where limited studies can be found, especia...
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New environmental regulations have driven companies to adopt low-carbon manufacturing. This research is aimed at considering carbon dioxide in the operational decision level where limited studies can be found, especially in the scheduling area. In particular, the purpose of this research is to simultaneously minimize carbon emission and total late work criterion as sustainability-based and classical-based objective functions, respectively, in the multiobjective job shop scheduling environment. In order to solve the presented problem more effectively, a new multiobjective imperialist competitive algorithm imitating the behavior of imperialistic competition is proposed to obtain a set of non-dominated schedules. In this work, a three-fold scientific contribution can be observed in the problem and solution method, that are: (1) integrating carbon dioxide into the operational decision level of job shop scheduling, (2) considering total late work criterion in multi-objective job shop scheduling, and (3) proposing a new multi-objective imperialist competitive algorithm for solving the extended multi-objective optimization problem. The elements of the proposed algorithm are elucidated and forty three small and large sized extended benchmarked data sets are solved by the algorithm. Numerical results are compared with two well-known and most representative metaheuristic approaches, which are multi-objective particle swarm optimization and non-dominated sorting genetic algorithm II, in order to evaluate the performance of the proposed algorithm. The obtained results reveal the effectiveness and efficiency of the proposed multi-objective imperialist competitive algorithm in finding high quality non-dominated schedules as compared to the other metaheuristic approaches.
The protein structure prediction (PSP) problem, i.e., predicting the three-dimensional structure of a protein from its sequence, remains challenging in computational biology. The inaccuracy of existing protein energy ...
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The protein structure prediction (PSP) problem, i.e., predicting the three-dimensional structure of a protein from its sequence, remains challenging in computational biology. The inaccuracy of existing protein energy functions and the huge conformation search space make the problem difficult to solve. In this study, the PSP problem is modeled as a multi-objective optimization problem. A physics-based energy function and a knowledge-based energy function are combined to construct the three-objective energy function. An improved multi-objective particle swarm optimization coupled with two archives is employed to execute the conformation space search. In addition, a mechanism based on Pareto non-dominated sorting is designed to properly address the slightly worse solutions. Finally, the experimental results demonstrate the effectiveness of the proposed approach. A new perspective for solving the PSP problem by means of multi-objectiveoptimization is given in this paper. (C) 2018 Published by Elsevier B.V.
The combination optimization of the train operation plan is an ongoing challenge: while computing power has improved, it is difficult to obtain a complete train operation plan system. With the aim of generating system...
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The combination optimization of the train operation plan is an ongoing challenge: while computing power has improved, it is difficult to obtain a complete train operation plan system. With the aim of generating system-optimal operation strategies, a new collaborative optimization method is proposed for line planning problem. Through a set of constraints, the problem is formulated as a two-objective model with the objectives of economic benefits and market effects. An optimization approach with adaptive improvement of control parameters based on the multi-objective differential evolution (MODE) algorithm is proposed to solve the model, and a heuristic algorithm is designed to get a better initial solution. Finally, computational results on benchmark multi-objectiveproblems show that the improvements of the strategies are positive and the optimization result of the improved algorithm has better stability. Meanwhile, based on a numerical example of a practical case study involving a 397-kilometer railway corridor to demonstrate the effectiveness of the proposed model and solution. As the basis of successive decisions, this method can adjust the number of trains according to the passenger fiow demand, which greatly saves operating costs.
In this paper, a mooring system design methodology combining the Non-dominated Sorting Genetic Algorithm-II (NSGA-II) with the vessel-mooring coupled model is first proposed. In the proposed methodology, the multi-obj...
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In this paper, a mooring system design methodology combining the Non-dominated Sorting Genetic Algorithm-II (NSGA-II) with the vessel-mooring coupled model is first proposed. In the proposed methodology, the multi-objective optimization problem for mooring system design which involves several design variables, objective functions and constraints is established and solved by the combination of the NSGA-II algorithm and the vessel-mooring coupled model, and the initial feasible range of design variables is narrowed in advance by combining the NSGA-II with the quasi-static mooring system model. A case study is presented to demonstrated the proposed methodology, in which a catenary mooring system is designed from scratch for a semi-submersible very large floating structure (VLFS) module. It can be concluded from the obtained results that, owing to the combination of the NSGA-II algorithm and the vessel-mooring coupled model, the accurate dynamic responses of vessel and mooring systems can be used as the objective functions;thus, the proposed methodology is able to attain an optimal mooring system considering more practical design requirements, such as the vessel motion response, the safety factor of the mooring system, the length of mooring line lay down part and mooring system layout.
This paper deals with design for manufacturing (DFM) approach for additive manufacturing (AM) to investigate simultaneously the different attributes and criteria of design and manufacturing. The integrated design appr...
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This paper deals with design for manufacturing (DFM) approach for additive manufacturing (AM) to investigate simultaneously the different attributes and criteria of design and manufacturing. The integrated design approach is provided in the product definition level and it gradually maps the customer requirements to the final product model. The main contribution of this paper is an interface processing engine that is an interface between the product model and manufacturing model. This study uses the Skin-Skeleton approach to model the first definition of the product and model the material flow of AM technology as the manufacturing process. This engine is developed through analysis of all AM technologies and identification of their parameters, criteria, and drawbacks. In order to evaluate some product and process parameters, a multi-objectiveproblem is formulated based on the analysis of all AM technologies;production time and material mass are optimized regarding mechanical behavior of the material and roughness of product. The approach is validated by a case study through a bag hook example. From its requirement specification to the proposed approach, this article defines an optimized product and its manufacturing parameters for fused deposition modeling (FDM) technology.
The turnaround is a critical airport process where a set of interrelated operations need to be performed to get an aircraft ready for its next flight. These activities are carried out by different vehicles, which need...
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The turnaround is a critical airport process where a set of interrelated operations need to be performed to get an aircraft ready for its next flight. These activities are carried out by different vehicles, which need to be coordinated to guarantee an efficient utilization of resources. Due to the relations between operations, the order in which these resources are scheduled has a critical influence on the planning and performance of the turnaround. In this work, we present a novel methodology for solving the proposed bi-objective ground handling scheduling problem from a global perspective. This means solving a set of interconnected routing problems with restrictive time windows for each operation. We first explore the solution space using a fast heuristic, focusing then on the most promising solutions to intensify the search in the vicinity of the Pareto frontier. This two-step schema permits significantly reducing the required computational time, which, in turn, allows a more thorough exploration of solutions. Different experiments over real data from two Spanish airports have been conducted to assess the proposed methodology. Our results show that the new method not only outperforms previous approaches in terms of computational requirements, but can also improve the quality of scheduling solutions.
In recent years, when solving MOPs, especially discrete path optimizationproblems, MOACOs concerning other meta-heuristic algorithms have been used and improved often, and they have become a hot research topic. This ...
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In recent years, when solving MOPs, especially discrete path optimizationproblems, MOACOs concerning other meta-heuristic algorithms have been used and improved often, and they have become a hot research topic. This article will start from the basic process of ant colony algorithms for solving MOPs to illustrate the differences between each step. Secondly, we provide a relatively complete classification of algorithms from different aspects, in order to more clearly reflect the characteristics of different algorithms. After that, considering the classification result, we have carried out a comparison of some typical algorithms which are from different categories on different sizes TSP (traveling salesman problem) instances and analyzed the results from the perspective of solution quality and convergence rate. Finally, we give some guidance about the selection of these MOACOs to solve problem and some research works for the future.
With the rapid proliferation of big data, real-time processing of huge datasets becomes a challenging task;primarily because of their heterogeneous nature. Due to this, one of the most serious concerns of the modern c...
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ISBN:
(纸本)9781538631805
With the rapid proliferation of big data, real-time processing of huge datasets becomes a challenging task;primarily because of their heterogeneous nature. Due to this, one of the most serious concerns of the modern cloud data centers is massive energy consumption during job execution. Hence, energy-aware task scheduling with data placement are considered as two important parameters for enhanced energy efficiency of modern cloud data centers. Moreover, considering the "pay-per-use" model of cloud computing infrastructure, it is important to maintain desirable service level agreement (SLA) while attaining improved data locality. Poor task scheduling decisions with limited focus of data locality are the prime reasons for escalated data communications and energy utilization levels. In order to deal with the aforementioned issues, data locality-aware energy-efficient (EnLoc) scheme for task scheduling and data placement has been proposed, particularly for MapReduce framework. The proposed EnLoc scheme is a multi-objective optimization problem (MOOP) and is solved using multi-objective evolutionary algorithm with "Tchebycheff decomposition";wherein the formulated MOOP is decomposed into theoretically finite number of subproblems to get optimal scheduling and placement decisions. The proposed scheme has been evaluated on real-time data traces acquired from OpenCloud Hadoop Cluster. The results obtained clearly demonstrate that the proposed EnLoc scheme outperforms the existing schemes in terms of energy efficiency, SLA assurance, and data locality.
Contract distribution is widely exists in modem commercial society, which mainly depends on qualitative analysis, and there still lack studies of quantitative analysis. Based on multi-objective estimation of distribut...
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ISBN:
(纸本)9781450364195
Contract distribution is widely exists in modem commercial society, which mainly depends on qualitative analysis, and there still lack studies of quantitative analysis. Based on multi-objective estimation of distribution algorithm (MOEDA), quantitative research idea on contract distribution is explored in this article. First of all, multi-objectiveoptimization model is built for contract distribution. Then, the algorithm flow base on MOEDA is designed. At last, simulations are carried out and compare with multi-objective genetic algorithm (MOGA). The simulation results show that the MOEDA performs better than MOGA, and verify the effectiveness and robustness of the proposed method in optimization of contract distribution.
multi-objective optimization problem is a kind of problem optimizing simultaneously several conflicting objectives and keeping a balance between the diversity and the convergence of solutions. In this paper, some nove...
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ISBN:
(纸本)9781538684818
multi-objective optimization problem is a kind of problem optimizing simultaneously several conflicting objectives and keeping a balance between the diversity and the convergence of solutions. In this paper, some novel techniques are designed to improve the efficiency of multi-objective evolutionary algorithms. Firstly, fitness in keeping with feasibility is designed to choose the individual with good feasibility as much as possible;secondly, a specific sub-function is separated from a series of objectives, which is applied to provide an approximate search direction and speed the convergence of the algorithm. Thirdly, differential evolution is used to make the population search to the optimal solutions;then, the crowding degree scheme, as in NSGA-II, is used to select potential promising solutions in the process of iterations such that Pareto front is uniform as much as possible. Finally, a novel multi-objective evolutionary algorithm is presented by embedding these schemes. The simulation illustrates the effectives of the proposed algorithm.
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