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IIAI 4th International Congress on Advanced Applied Informatics (IIAI-AAI)

作者： Sopov, Evgenii Siberian State Aerosp Univ SibSAU Syst Anal & Operat Res Dept Krasnoyarsk Russia

ISBN: (纸本)9781479999583

Many complex optimization problems require a modification of the general evolutionary algorithm (EA) according to the given features of the problem. There exist a great variety of EAs that represent different search strategies for many classes and subclasses of optimization problems. Real-world problems may combine several features that are not known beforehand, thus there is no information about what EA to choose and what EA's settings to apply for efficient problem solving. This study presents a novel metaheuristic for designing multi-strategy EA based on the hybrid of the island model, cooperative and competitive coevolution schemes. The approach controls interactions of EAs and leads to the self-configuring solving of problems with a priori unknown structure. Two examples of implementations of the approach for multi-objective and non-stationary optimization are discussed. The results of numerical experiments for benchmark problems from CEC competitions are presented. The proposed approach has demonstrated the efficiency comparable with other well-studied techniques for multi-objective and non-stationary optimization. And it does not require the participation of the human-expert, because it operates in an automated, self-configuring way.

关键词： self-configuration multi-strategy evolutionary algorithm multi-objective genetic algorithm non-stationary optimization

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Time-Cost Trade-off Problem under Uncertainty Incorporating multi-objective genetic algorithm and Fuzzy Sets Theory

Time-Cost Trade-off Problem under Uncertainty Incorporating ...

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2010 IEEE 17th International Conference on Industrial Engineering and Engineering Management(2010年IEEE第17届工业工程与工程管理国际学术会议)

作者： C.H.Ding W.Wei X.Wei S.Fujimura Graduate School of Information Production and SystemsWaseda UniversityKitakyusyuJapan School of E Graduate School of Information Production and SystemsWaseda UniversityKitakyusyuJapan

The time-cost trade-off problem (TCTP) is an important branch in the project scheduling problem. However, the duration and cost of each activity could change stochastically as a result of uncertain factors. To meet the needs of real projects, an improved approach based on trapezoid fuzzy numbers is applied to estimate the uncertainty of time and cost. And then α-cut method is applied to decide the risk level. Furthermore, improved crossover and mutation methods for multiobjective genetic algorithm (MOGA) are used to make a large-scale computation possible. The efficiency of the proposed approach is verified by comparison with previous researches. In addition, economic analysis skill of finance cost is integrated into the new model to provide greater flexibility to managers when making decisions. Finally, time-cost tables under different risk levels for case examples are given and the advantages are investigated based on computation results.

关键词： Finance cost Fuzzy sets theory multi-objective genetic algorithm Project scheduling Risk management Time-cost trade-off problem

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Fuzzy delay model based fault simulator for crosstalk delay fault test generation in asynchronous sequential circuits

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SADHANA-ACADEMY PROCEEDINGS IN ENGINEERING SCIENCES 2015年第1期40卷 107-119页

作者： Jayanthy, S. Bhuvaneswari, M. C. Sri Ramakrishna Engn Coll Dept Elect & Commun Engn ECE Coimbatore 641022 Tamil Nadu India PSG Coll Technol Dept Elect & Elect Engn EEE Coimbatore 641004 Tamil Nadu India

In this paper, a fuzzy delay model based crosstalk delay fault simulator is proposed. As design trends move towards nanometer technologies, more number of new parameters affects the delay of the component. Fuzzy delay models are ideal for modelling the uncertainty found in the design and manufacturing steps. The fault simulator based on fuzzy delay detects unstable states, oscillations and non-confluence of settling states in asynchronous sequential circuits. The fuzzy delay model based fault simulator is used to validate the test patterns produced by Elitist Non-dominated sorting genetic algorithm (ENGA) based test generator, for detecting crosstalk delay faults in asynchronous sequential circuits. The multi-objective genetic algorithm, ENGA targets two objectives of maximizing fault coverage and minimizing number of transitions. Experimental results are tabulated for SIS benchmark circuits for three gate delay models, namely unit delay model, rise/fall delay model and fuzzy delay model. Experimental results indicate that test validation using fuzzy delay model is more accurate than unit delay model and rise/fall delay model.

关键词： Asynchronous sequential circuits crosstalk delay faults fuzzy delay model multi-objective genetic algorithm fault coverage transitions

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Optimization of heat transfer enhancement of nanofluid in a channel with winglet vortex generator

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APPLIED THERMAL ENGINEERING 2015年 91卷 1116-1126页

作者： Abdollahi, Azita Shams, Mehrzad KN Toosi Univ Technol Fac Mech Engn Tehran Iran

A numerical simulation was performed to investigate the effect of the nanoparticles, vortex generator and combination of them on heat transfer and fluid flow characteristics in a rectangular channel using Commercial Computational Fluid Dynamics Code FLUENT. Euler-Lagrangian approach was utilized in the numerical modeling of the nanofluids. The fluid was considered as a continuous phase and the heat and flow fields were analyzed by solving Navier-Stokes and energy equations and the nanoparticles were simulated as a discrete phase in a Lagrangian frame. The thermal and hydraulic performances of the channel were investigated at different nanoparticle concentration, shape and angle of attack of the vortex generator. According to the results, the Nusselt number increases by raising the nanoparticles concentration and adding nanoparticles is more effective than placing VG from thermal point of view in the range of study. Using a combination of these heat transfer enhancers maximizes the thermal performance of the channel as well as the flow resistance. So, in order to achieve the best thermal-hydraulic performance, combination of the computational fluid dynamics analyses, artificial neural networks and multi-objective genetic algorithm was used to determine the optimal values of these parameters. Finally, a set of optimal solutions as well as the best shape, angle of attack of the VG and nanoparticles volume fraction was obtained. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Heat transfer enhancement Vortex generator Nanofluids multi-objective genetic algorithm Artificial neural network

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The interplay between renewables penetration, costing and emissions in the sizing of stand-alone hydrogen systems

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INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 2015年第1期40卷 125-135页

作者： Brka, Adel Al-Abdeli, Yasir M. Kothapalli, Ganesh Edith Cowan Univ Sch Engn Joondalup WA 6027 Australia

multi-objective genetic algorithms are used to optimise three stand-alone hydrogen systems (WG-H-2, WG/PV-H-2 and PV-H-2) under three different objective functions: minimising (hardware) Net Present Cost - NPC ($), whole Life Cycle Emissions - LCE (CO2-eq/yr) and dumped/Excess Energy -EE (%) at low demand. Optimisations considering Excess Energy haven't been reported before. Simulations are implemented using MATLAB, incorporate experimentally resolved fuel cell start-up transients, and dynamic profiles for wind speed, solar irradiance as well as electric load demand. Results indicate the significance of integrating fuel cell start-up into the LPSP when optimising systems, another aspect not reported before and a modified LPSP is introduced. Furthermore, when sizing energy systems by reducing LCE, EE, and NPC, the favoured hybrid architecture appears to be WG-H-2 over the others studied. For the same LPSP, an interesting finding is that increased renewables penetration (reduced dumped loads) affects the optimised solution but comes at a cost. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

关键词： Hydrogen energy Systems optimization multi-objective genetic algorithm Experiments Transient start-up Life cycle emissions

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Time-Cost Trade-off Problem under Uncertainty Incorporating multi-objective genetic algorithm and Fuzzy Sets Theory

Time-Cost Trade-off Problem under Uncertainty Incorporating ...

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第17届工业工程与工程管理国际学术会议(IE&EM2010)

作者： S.Fujimura Graduate School of Information Production and SystemsWaseda UniversityKitakyusyuJapan

The time-cost trade-off problem(TCTP) is an important branch in the project scheduling problem. However,the duration and cost of each activity could change stochastically as a result of uncertain *** meet the needs of real projects,an improved approach based on trapezoid fuzzy numbers is applied to estimate the uncertainty of time and *** thenα-cut method is applied to decide the risk ***,improved crossover and mutation methods for multi-objective genetic algorithm(MOGA) are used to make a large-scale computation *** efficiency of the proposed approach is verified by comparison with previous researches. In addition,economic analysis skill of finance cost is integrated into the new model to provide greater flexibility to managers when making ***,time-cost tables under different risk levels for case examples are given and the advantages are investigated based on computation results.

关键词： Finance cost Fuzzy sets theory multi-objective genetic algorithm Project scheduling Risk management Time-cost trade-off problem

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Theoretical analysis and design optimization of wideband input/output branch waveguide couplers for a sheet beam traveling wave tube

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JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS 2015年第15期29卷 2002-2013页

作者： Shu, G. X. Wang, J. X. Liu, G. Zheng, Y. Yang, L. Y. Luo, Y. Univ Elect Sci & Technol China Sch Phys Elect Chengdu 610054 Peoples R China Univ Calif Davis Dept Appl Sci Davis CA 95616 USA

The branch waveguide coupler (BWC) with an intrinsically excellent microwave property in an extremely wide frequency range was proposed to build the input/output (I/O) structure for the sheet beam traveling wave tube. The odd and even mode theory is utilized to analyze the BWC. Based on the theory, a code is written to calculate its microwave performance parameters. The numerical calculation has a good agreement with the computation simulation. To improve the efficiency of developing the BWC, a novel design optimization approach based on the MATLAB optimization tool is proposed. A BWC with nine branch waveguides is optimized using multi-objective genetic algorithm. In addition to the excellent microwave property, a compact configuration is achieved. It is predicted that the I/O structure possesses a very good performance with coupling above -0.3dB, port reflectivity under -19dB, and isolation less than -15dB in a broad frequency range of 37.4-51.0GHz, corresponding to a bandwidth of 13.6GHz (30.7%).

关键词： sheet beam traveling wave tubes input output structure multi-objective genetic algorithm odd and even mode theory branch waveguide coupler wideband coupler

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Determination of interfacial heat transfer coefficients in a sand mould casting process using an optimised inverse analysis

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APPLIED THERMAL ENGINEERING 2015年 78卷 682-694页

作者： Palumbo, Gianfranco Piglionico, Vito Piccininni, Antonio Guglielmi, Pasquale Sorgente, Donato Tricarico, Luigi Politecn Bari DMMM Bari Italy

Determination of the interface heat transfer coefficients in casting processes represents a fundamental step in the creation of a reliable numerical model that can predict some of the most common defects (for example hot tear or residual stress) which may affect the process. This work focuses on the most appropriate methodology to determine the heat transfer coefficients for the numerical modelling of the casting process of a super duplex stainless steel (ASTM A890 Gr. 5A) using a silica sand mould. Experimental instrumented castings were used to acquire (both in the casting and in the sand) temperature changes for a number of points of interest by means of thermocouples;in addition, the entire process was simulated using the finite difference method commercial software package MAGMASOFT((R)) (v. 5.2) in order to calculate the temperature at the same points at any step of the process. Firstly, the most influential input parameters were chosen in order to determine the factors to be investigated using a reduced factorial scheme. Further simulations, in which the value of the chosen factors was changed, made it possible to create response surfaces using as a response variable the value of the mismatch between the experimental and numerical temperature changes in the same points. Finally, the optimisation procedure using a multi-objective genetic algorithm was performed, with the goal of finding optimal values for the input parameters, i.e. those with which the mismatch between experimental and numerical temperature changes is minimised. As confirmed by the numerical simulations using the results of the optimisation procedure, the methodology proposed enabled us to determine the correct values of the input variables for modelling the casting process of the ASTM A890 Gr. 5A. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： Super duplex stainless steel (ASTM A890 Gr. 5A) Casting MAGMASoft Interface heat transfer coefficients Response surface multi-objective genetic algorithm

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Influence of solution heat treatment on mechanical response and fracture behaviour of aluminium alloy sheets: An experimental study

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MATERIALS & DESIGN 2015年 88卷 1119-1126页

作者： Ma, Wenyu Wang, Baoyu Yang, Lei Tang, Xuefeng Xiao, Wenchao Zhou, Jing Univ Sci & Technol Beijing Sch Mech Engn Beijing 100083 Peoples R China

Solution heat treatment (SHT), as a part of a consolidated process involving quenching and artificial ageing, significantly affects the mechanical properties of AA6082 sheets. In this study, SHT temperature and time were analysed as main design variables. Specimens were subjected to SHT by using central composite design and then processed by water quenching and artificial ageing (190 degrees C/3 h). Tension tests were conducted at room temperature to measure the tensile strength and formability of the specimens. Response surface models for ultimate tensile stress (UTS) and ductility were constructed as a function of the design variables. UTS generally increased and ductility decreased with increasing SHT temperature and time. This result was processed using the multiobjective sorting genetic algorithm NSGA-II to optimise design parameters and improve UTS and ductility. Pareto optimal solutions corresponding to UTS and ductility and appropriate ranges of design variables were obtained. The fracture characteristics of the alloy parts formed after tensile tests were further analysed using scanning electron microscopy. The fracture mode was the ductile fracture. Increasing SHT temperature and time made the dimples to be shallow and less. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Aluminium alloy Solution heat treatment Response surface model multi-objective genetic algorithm Fracture morphology

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A real-time forecasting model for the spatial distribution of typhoon rainfall

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JOURNAL OF HYDROLOGY 2015年 521卷 302-313页

作者： Lin, Gwo-Fong Jhong, Bing-Chen Natl Taiwan Univ Dept Civil Engn Taipei 10617 Taiwan

Accurate forecasts of hourly rainfall are necessary for early warning systems during typhoons. In this paper, a typhoon rainfall forecasting model is proposed to yield 1- to 6-h ahead forecasts of hourly rainfall. First, an input optimization step integrating multi-objective genetic algorithm (MOGA) with support vector machine (SVM) is developed to identify the optimal input combinations. Second, based on the results of the first step, the forecasted rainfall from each station is used to obtain the spatial characteristics of the rainfall process is presented. An actual application to Tsengwen river basin is conducted to demonstrate the advantage of the proposed model. The results clearly indicate that the proposed model effectively improves the forecasting performance and decreases the negative impact of increasing forecast lead time. The optimal input combinations can be obtained from the proposed model for different stations with different geographical conditions. In addition, the proposed model is capable of producing more acceptable the results of rainfall maps than other model. In conclusion, the proposed modeling technique is useful to improve the hourly typhoon rainfall forecasting and is expected to be helpful to support disaster warning systems. (C) 2014 Elsevier B.V. All rights reserved.

关键词： Hourly typhoon rainfall forecasting Spatial characteristics Meteorological data multi-objective genetic algorithm Support vector machine

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