A reasonable system capacity allocation scheme is basis for the utilization of renewable energy. Firstly, based on environment of desert areas, a capacity optimization model of WPTP hybrid system is established. Then,...
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Impossible differential cryptanalysis is an efficient cryptanalysis method in the field of block ciphers, and mixedintegerlinearprogramming (MILP) is widely used in the automatic search for impossible differentials...
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Purpose - Distribution network design involves a set of strategic decisions in supply chains because of their long-term impacts on the total logistics cost and environment. To incorporate a trade-off between financial...
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Purpose - Distribution network design involves a set of strategic decisions in supply chains because of their long-term impacts on the total logistics cost and environment. To incorporate a trade-off between financial and environmental aspects of these decisions, this paper aims to determine an optimal location, among candidate locations, of a new logistics center, its capacity, as well as optimal network flows for an existing distribution network, while concurrently minimizing the total logistics cost and gas emission. In addition, uncertainty in transportation and warehousing costs are considered. Design/methodology/approach - The problem is formulated as a fuzzy multiobjective mathematical model. The effectiveness of this model is demonstrated using an industrial case study. The problem instance isa four-echelon distribution network with 22 products and a planning horizon of 20 periods. The model is solved by using the min-max and augmented << -constraint methods with CPLEX as the solver. In addition to illustrating model's applicability, the effect of choosing a new warehouse in the model is investigated through a scenario analysis. Findings - For the applicability of the model, the results indicate that the augmented << -constraint approach provides a set of Pareto solutions, which represents the ideal trade-off between the total logistics cost and gas emission. Through a case study problem instance, the augmented << -constraint approach is recommended for similar network design problems. From a scenario analysis, when the operational cost of the new warehouse is within a specific fraction of the warehousing cost of third-party warehouses, the solution with the new warehouse outperforms that without the new warehouse with respective to financial and environmental ***/value - The proposed model is an effective decision support tool for management, who would like to assess the impact of network planning decisions on the performance of their sup
Electric vehicle sharing systems deployed in large cities provide alternative means of transportation for non-vehicle owners and visitors. This work considers the optimal design of a one-way station-based electric veh...
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ISBN:
(纸本)9798350373981;9798350373974
Electric vehicle sharing systems deployed in large cities provide alternative means of transportation for non-vehicle owners and visitors. This work considers the optimal design of a one-way station-based electric vehicle sharing system. Location of charging stations is assumed to be known so that the main strategic decisions regard the installation of charging ports at stations and the acquisition of electric vehicles. To assess the future system profitability, the strategic problem modeling should integrate tactical and operational decisions representing how the system will operate on a daily basis. This work investigates whether modeling an operational feature, vehicle relocation by employees, has a strong impact on the quality of the design decisions recommended by the optimization model.
In order to meet item demands, end-of-life (EOL) product and subassembly ordering and disassembly schedules are determined by disassembly lot sizing, which is the subject of this study. We take into consideration a st...
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ISBN:
(纸本)9798350373981;9798350373974
In order to meet item demands, end-of-life (EOL) product and subassembly ordering and disassembly schedules are determined by disassembly lot sizing, which is the subject of this study. We take into consideration a stochastic version with undetermined ordering lead time (OLT). In this case, OLT stands for the amount of time that passes between placing and receiving an order (we can only order EOL products). Throughout the planning horizon, scenarios are used to model the stochasticity. The objective is to reduce the expected total of setup, purchasing, inventory, and backlog expenses. This is achieved by expressing the problem as a two-stage mixedintegerlinearprogramming (2S-MILP) model across all potential scenarios. The 2S-MILP is unsolvable since it is predicated on every scenario conceivable. A Simultaneous Backward Reduction approach is proposed to make it tractable. To confirm the suggested method's efficacy, it is assessed in a variety of environments.
In this study, we introduce the Covering Tour Problem with Arc Upgrade (CTPAU), an extension of the Covering Tour Problem (CTP) that exploits the possibility of enhancing the network by upgrading arcs. The CTP is defi...
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ISBN:
(纸本)9783031782404;9783031782411
In this study, we introduce the Covering Tour Problem with Arc Upgrade (CTPAU), an extension of the Covering Tour Problem (CTP) that exploits the possibility of enhancing the network by upgrading arcs. The CTP is defined on a graph consisting of three sets of nodes: those requiring coverage, those eligible to provide coverage, and a subset of the latter which must be visited. The objective is to determine the minimum cost tour that complies with both visiting and covering requirements. We introduce a further aspect on the problem given by the possibility of arc upgrades. Such upgrades decrease the length of an arc, usually within specific limits, incurring a cost directly proportional to the degree of reduction. Thus, the CTPAU aims to determine the minimum cost tour that meets the CTP requirements and incorporates the possibility of upgrading arcs, satisfying a budget constraint. To address this problem, we developed a mixedintegerlinearprogramming formulation and conducted experiments on benchmark instances from TSPLIB to assess our approach.
The state-of-the-art approach for computing alignments is to apply an exhaustive state-space search with a well-tailored A*-heuristic function. If the heuristic fails to provide good estimates, the alignment computati...
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The benefits of thermal storage in hybrid energy systems (HESs) are multiple, being among others the enhancement of flexibility of the network and of the efficiency in the energy resources use, by also reducing the ov...
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The benefits of thermal storage in hybrid energy systems (HESs) are multiple, being among others the enhancement of flexibility of the network and of the efficiency in the energy resources use, by also reducing the overall cost of the energy system. Choosing the capacity of TSS to minimize the operational cost of the HES is not a trivial task, depending on several variables existing at both supply and demand sides. The contribution of this paper is to present the experimental validation of an innovative optimization model aiming to identify the optimal capacity of TSS in HESs that maximizes the economic performances. The optimization model is based on a mixed-integer linear programming approach and allows determining the optimal hourly operating strategies of the system components as well as the optimal capacity of the TSS, while minimizing the total daily energy costs. The optimized hourly operation schedule of the HES was simulated experimentally by using one of the systems from the TSS laboratory of ENEA Portici Research Center. The experimental results demonstrated the practical applicability of the proposed optimization model. In fact, a good overlap was found between the results obtained from the implementation of the optimization model with those obtained from the experimental simulation, both considering energy and economic data.
In this paper, we propose a novel mixed-integer Non-linear Optimization formulation to construct a risk score, where we optimize the logistic loss with sparsity constraints. Previous approaches are typically designed ...
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The transition to sustainable energy systems has highlighted the critical need for efficient sizing of renewable energy resources in microgrids. In particular, designing photovoltaic (PV) and battery systems to meet r...
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