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multiobjective optimization to a TB-HIV/AIDS coinfection optimal control problem

COMPUTATIONAL & APPLIED MATHEMATICS 2018年第2期37卷 2112-2128页

作者： Denysiuk, Roman Silva, Cristiana J. Torres, Delfim F. M. Univ Minho Algoritmi R&D Ctr Braga Portugal Univ Aveiro Ctr Res & Dev Math & Applicat CIDMA Dept Math P-3810193 Aveiro Portugal

We consider a recent coinfection model for Tuberculosis (TB), Human Immunodeficiency Virus (HIV) infection, and Acquired Immunodeficiency Syndrome (AIDS) proposed in Silva and Torres (Discr Contin Dyn Syst 35(9):4639-4663, 2015). We introduce and analyze a multiobjective formulation of an optimal control problem, where the two conflicting objectives are minimization of the number of HIV-infected individuals with AIDS clinical symptoms and coinfected with AIDS and active TB;and costs related to prevention and treatment of HIV and/or TB measures. The proposed approach eliminates some limitations of previous works. The results of the numerical study provide comprehensive insights about the optimal treatment policies and the population dynamics resulting from their implementation. Some nonintuitive conclusions are drawn. Overall, the simulation results demonstrate the usefulness and validity of the proposed approach.

关键词： Tuberculosis HIV Epidemic model Treatment strategies Optimal control theory multiobjective optimization

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multiobjective optimization research on the response time of a pneumatic pilot-operated high speed on/off valve

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INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS 2021年第1期65卷 109-127页

作者： Li, Tao Zhang, Youtong Liang, Yuxiu Yang, Ye Jiao, Jie Beijing Inst Technol Lab Low Emiss Vehicle Beijing Peoples R China North China Univ Sci & Technol Qinggong Coll Tangshan Hebei Peoples R China Beijing Benz Automot Co Beijing Peoples R China

In order to solve the contradiction between the opening and closing time of the high speed on/off valve for space propulsion systems of the liquid rocket engine, a pneumatic pilot-operated high speed on/off valve is proposed and multiobjective optimization for the opening and closing time of the valve is carried out in this paper. Based on the analysis of the working mechanism of the valve, the mathematical models for the pilot valve and the main valves are established respectively. The Plackett-Burman design is used to select the optimization variables which influence the performance of the response time significantly. The central composite design is used to obtain the sample points and establish second-order response surface models of the response time. The NSGA-II is used to obtain the Pareto front of the optimization objectives. The optimized opening and closing time can be reduced by 17.7% and 37.4% respectively. A prototype based on the optimized parameters is manufactured and tested to verify the accuracy of the multiobjective optimization results. The test results verify the validity of the optimization approach for the proposed valve in this paper.

关键词： multiobjective optimization pneumatic pilot-operated high speed on/off valve response surface model response time solenoid valve

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multiobjective optimization of Signal Timings for Two-Stage, Midblock Pedestrian Crosswalk

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TRANSPORTATION RESEARCH RECORD 2011年第2264期2264卷 34-43页

作者： Ma, Wanjing Liu, Yue Xie, Hanzhou Yang, Xiaoguang Tongji Univ Minist Educ Key Lab Rd & Traff Engn Shanghai 200092 Peoples R China Univ Wisconsin Dept Civil Engn Milwaukee WI 53211 USA

To improve convenience and safety for pedestrians, signalized two-stage, midblock pedestrian crosswalks are increasingly being installed in highly populated areas in developing countries such as China. This paper presents a multiobjective optimization model and its solution algorithm for optimal control of a two-stage, midblock crosswalk on a street with both vehicular and pedestrian traffic. The proposed model aims to produce the optimal signal timings at the crosswalk to accommodate both traffic modes and to adjust the offsets of the pedestrian signals for the two stages concurrently to minimize pedestrian delays and relieve congestion at a central refuge island, the safe area for *** to stop. The proposed model and algorithm have three distinguishing features: (a) they explicitly model pedestrian delays at the two-stage controlled crosswalk, including delays at both the curbside and the central refuge island;(b) they model the number of pedestrians waiting on the central refuge island according to the change in signal timing;and (c) they have application in a multiobjective optimization approach to study the effectiveness of midblock crosswalk control under conditions in which the priorities between vehicular and pedestrian traffic differ. A heuristic based on nondominated sorting genetic algorithm II was designed to solve the model and generate the Pareto solution set for signal timings. The results of the case study showed that the proposed model would help traffic practitioners, researchers, and authorities properly design signal timing plans and central refuge islands for two-stage midblock pedestrian crosswalks.

关键词： multiobjective optimization

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multiobjective optimization of a Dual Stator Brushless Hybrid Excitation Motor Based on Response Surface Model and NSGA 2

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IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS 2022年第5期58卷 6105-6114页

作者： Wang, Xu Fan, Ying Lu, Xingchi Chen, Qiushuo Lee, Christopher H. T. Southeast Univ Nanjing 210096 Peoples R China Nanyang Technol Univ Singapore 639798 Singapore

This article proposes a multiobjective optimization design framework for a double stator brushless hybrid excitation motor (DSBHEM) to provide high torque, wide flux regulation ability and low torque ripple. The design variables are divided into sensitive level and insensitive level by sensitivity analysis. The response surface model (RSM) and nondominated sorting genetic algorithm 2 (NSGA2) are organically combined to generate a set of Pareto solutions for the sensitive level variables, from which the optimal values of the sensitive level variables are obtained. In addition, the optimal values of insensitive variables are obtained through single parameter scanning optimization, and a set of final optimal design variables are obtained. The electromagnetic performance of the initial design and the optimal design are compared with finite element analysis. Finally, a prototype is manufactured to verify the proposed concepts.

关键词： optimization Windings Brushless motors Stator windings Reluctance motors Regulation Iron Brushless hybrid excitation multiobjective optimization nondominated sorting genetic algorithm response surface model sensitivity analysis

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multiobjective optimization of a sugarcane biorefinery involving process and environmental aspects

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RENEWABLE ENERGY 2016年第PartB期96卷 1142-1152页

作者： Borba Costa, Caliane Bastos Potrich, Erich Goncalves Cruz, Antonio Jose Fed Univ Sao Carlos UFSCar Chem Engn Grad Program Chem Eng Dept UFSCar Rodovia Washington LuisKm 235 BR-13565905 Sao Carlos SP Brazil Fed Univ Sao Carlos UFSCar Dept Chem Engn UFSCar Rodovia Washington LuisKm 235 BR-13565905 Sao Carlos SP Brazil

Process modeling and simulation are essential to predict process energetic demands, and determine possible throughputs and process emissions in biorefineries. In this paper non-linear multiobjective optimization studies with conflicting process and environmental objectives are performed in a sugarcane biorefinery. The process produces bioethanol (first and second generation), bioelectricity and concentrates vinasse in multiple-effect evaporators. Objective functions, concerning process and environmental issues, are defined and studied in five optimization problems. Decision variables are fraction of bagasse diverted to E2G production (Var1), and the fraction of vinasse that is concentrated up to 7.0 degrees Bx in multiple-effect evaporator (Var2). The results show that Varl cannot assume values greater than circa 0.5, due to thermal demands of the integrated process, while Var2 cannot be lower than 0.15, due to process demands for vegetal steam. Flows of concentrated vinasse are generally higher when maximization of bioethanol throughputs is imposed. When electric power generation and bioethanol throughput maximization are the objectives, the former varies 45.6%, while the latter varies 16.6%, among non-dominated solutions. The adopted approach can be used as a decision-making tool that may help to choose suitable operating conditions, in order to obtain a trade-off between greater profits and a more sustainable process. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： multiobjective optimization Ethanol Electric energy Vinasse concentration CO2 emission Sugarcane biorefinery

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multiobjective optimization of viscoelastic laminated sandwich structures using the Direct MultiSearch method

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COMPUTERS & STRUCTURES 2015年 147卷 229-235页

作者： Madeira, J. F. A. Araujo, A. L. Mota Soares, C. M. Mota Soares, C. A. Univ Lisbon Inst Super Tecn IDMEC LAETA P-1049001 Lisbon Portugal Inst Super Engn Lisboa P-1959007 Lisbon Portugal

A multiobjective approach for optimization of passive damping for vibration reduction in sandwich structures is presented in this paper. Constrained optimization is conducted for maximization of modal loss factors and minimization of weight of sandwich beams and plates with elastic laminated constraining layers and a viscoelastic core, with layer thickness and material and laminate layer ply orientation angles as design variables. The problem is solved using the Direct MultiSearch (DMS) solver for derivative-free multiobjective optimization and solutions are compared with alternative ones obtained using genetic algorithms. (C) 2014 Civil-Comp Ltd and Elsevier Ltd. All rights reserved.

关键词： multiobjective optimization Direct MultiSearch Sandwich structures Damping

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multiobjective optimization of fractional frequency reuse for irregular OFDMA macrocellular deployments

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TELECOMMUNICATION SYSTEMS 2016年第4期61卷 659-673页

作者： Gonzalez, David G. Garcia-Lozano, Mario Ruiz, Silvia Lema, Maria A. Lee, Dongseop Aalto Univ Sch Elect Engn Dept Commun & Networking COMNET Espoo Finland Univ Politecn Cataluna BarcelonaTech Dept Signal Theory & Commun Barcelona Spain Kings Coll London London WC2R 2LS England Samsung DMC R&D Ctr Bldg Energy Management Syst Seoul South Korea

Interference mitigation has been identified as a key challenge for emerging cellular technologies based on Orthogonal Frequency Division Multiple Access, such as Long Term Evolution. In this context, static intercell interference coordination including Fractional Frequency Reuse (FFR) have been adopted by mobile operators as a good alternative to improve the quality of service at cell edges. Nevertheless, recent results made evident the need for additional research efforts as default FFR configurations only offer tradeoffs in which spectral efficiency is severely penalized. Moreover, the performance of such baseline designs has been showed to be poor in realistic cellular deployments featuring irregular cell patterns. This paper solves this problematic by introducing a novel multiobjective optimization framework based on evolutionary algorithms that jointly takes into account system capacity, cell edge performance, and energy consumption. With respect to important reference schemes, the proposed algorithm succeeds in finding FFR configurations achieving gains between 10 and 40 % in terms of system capacity while simultaneously improving cell edge performance up to 70 %.

关键词： Fractional frequency reuse FFR Long term evolution LTE multiobjective optimization

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multiobjective optimization of the antioxidant activities of horse mackerel hydrolysates produced with protease mixtures

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PROCESS BIOCHEMISTRY 2017年 52卷 149-158页

作者： Morales-Medina, R. Perez-Galvez, R. Guadix, A. Guadix, E. M. Univ Granada Dept Chem Engn E-18071 Granada Spain

Fish protein hydrolysates (FPH) from horse mackerel were produced by employing an enzyme mixture of subtilisin and trypsin. The antioxidant activity of fish hydrolysates (DPPH scavenging activity, Fe2+ chelating activity and Fe3+ reducing power) was modelled as a function of the operating conditions for the hydrolysis (i.e. protein concentration, temperature and composition of the enzyme mixture). The antioxidant activities showed different behavior depending on whether their controlling pathway was the transference of electrons/protons (i.e. DPPH scavenging activity and Fe3+ reducing power) or metal chelation. In the first case, the antioxidant activities increased with the decrease of substrate concentration and temperature when pure trypsin (DPPH scavenging activity) or a mixture of enzymes (Fe3+ reducing capacity) was employed. Contrarily, hydrolysates showed higher Fe2+ chelating activities at moderate concentration and high temperature (i.e. 5 g/L and 55 degrees C) employing solely subtilisin. The conflictive behavior among the antioxidant properties suggested using a multiobjective optimization technique. The epsilon-constraint method was chosen for this purpose. This approach allows determining the most adequate operational conditions for producing hydrolysate with a specific antioxidant profile which is the first approximation to the production of taylor-made antioxidant hydrolysates. (C) 2016 Elsevier Ltd. All rights reserved.

关键词： DPPH scavenging activity Fe2+ chelating activity Fe3+ reducing power multiobjective optimization Mixture of proteases

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multiobjective optimization for Train Speed Trajectory in CTCS High-Speed Railway With Hybrid Evolutionary Algorithm

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IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS 2015年第4期16卷 2215-2225页

作者： Wei ShangGuan Yan, Xi-Hui Cai, Bai-Gen Wang, Jian Beijing Jiaotong Univ Sch Elect & Informat Engn State Key Lab Rail Traff Control & Safety Beijing 100044 Peoples R China Beijing Jiaotong Univ Sch Elect & Informat Engn Beijing Engn Res Ctr EMC & GNSS Technol Rail Tran Beijing 100044 Peoples R China

A speed trajectory profile indicating the authorized train speed at each position can be used to guide the driver or the automatic train operation (ATO) system to operate the train more efficiently, which is the most important part of the Chinese Train Control System (CTCS) and will decide the safety and efficiency of train operation. The efforts produced by the train to follow the speed trajectory will directly affect the evaluation of train operation. This paper studies the optimization approach for the speed trajectory of high-speed train in a single section. First, we take the energy consumption as the measure of satisfaction of the railway company, and the trip time is being regarded as the passenger satisfaction criterion;then, we present optimal speed trajectory searching strategies under different track characteristics by dividing the section into some subsections according to different speed limitations. After that, we develop a multiobjective optimization model for the speed trajectory, which is subject to the constraints such as safety requirement, track profiles, passenger comfort, and the dynamic performance. For obtaining the Pareto frontier of train speed trajectory, which has equal satisfaction degree on all the objects, a hybrid evolutionary algorithm is designed and applied to solve the model based on the differential evolution and simulating annealing algorithms. By showing some numerical results of simulations, the efficiency of the proposed model and solution methodology is illustrated.

关键词： Chinese train control system (CTCS) energy efficient high-speed railway hybrid evolutionary algorithm multiobjective optimization train speed trajectory

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multiobjective optimization for Multiperiod Reverse Logistics Network Design

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IEEE TRANSACTIONS ON ENGINEERING MANAGEMENT 2016年第2期63卷 223-236页

作者： Li, Shuang Wang, Nengmin Jia, Tao He, Zhengwen Liang, Huigang Xi An Jiao Tong Univ Sch Management Xian 710049 Peoples R China Xi An Jiao Tong Univ Key Lab Minist Educ Proc Control & Efficiency Engn Xian 710049 Peoples R China E Carolina Univ Coll Business Dept Management Informat Syst Greenville NC 27858 USA

In recent years, the ever-rising return streams for repair service have forced the electronics manufacturers to expand their reverse logistics capacities. However, most existing papers on the reverse logistics network design neglected the time sensitivity of the return flows. Moreover, most of these investigations were primarily concerned with the single objective problems of either minimizing the total cost or maximizing the profit. In this paper, we propose a biobjective mixed-integer linear programming model for the multiperiod design problem of a reverse logistics network for repair service. A multiperiod setting is taken into account to make the reverse logistics network flexible to accommodate the gradual changes in the capacity of the facilities and the network configuration. To solve the NP-hard problem with biobjective, we develop a hybrid evolutionary algorithm that combines nondominated sorting genetic algorithm II (NSGA-II) with a local search method. We compare the hybrid evolutionary algorithm with NSGA-II and e-constraint method using numerical examples. The comparison results indicate that the hybrid evolutionary algorithm outperforms the NSGA-II in most cases. The e-constraint method performs best for the small instances, but it cannot solve large instances within reasonable time. Finally, an extensive parametric analysis is conducted and several managerial insights are derived.

关键词： Local search location distribution multiobjective optimization nondominated sorting genetic algorithm II (NSGA-II) reverse logistics network design

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