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multi-objective optimal design of small scale resistance spot welding process with principal component analysis and response surface methodology

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JOURNAL OF INTELLIGENT MANUFACTURING 2014年第6期25卷 1335-1348页

作者： Zhao, Dawei Wang, Yuanxun Sheng, Suning Lin, Zongguo Huazhong Univ Sci & Technol Sch Civil Engn & Mech Dept Mech Wuhan 430074 Peoples R China Miyachi Unitek Corp Grand Master Trading Ltd Nanjing 211100 Jiangsu Peoples R China

This paper investigates the effects of welding parameters on the welding quality and optimizes them in the small scale resistance spot welding (SSRSW) process. Experiments are carried out on the basis of response surface methodology technique with different levels of welding parameters of spot welded titanium alloy sheets. multiple quality characteristics, namely signal-to-noise (S/N) ratios of weld nugget diameter, penetration rate, tensile shear load and the failure energy, are converted into an independent quality index using principal component analysis. The mathematical model correlating process parameters and their interactions with the welding quality is established and discussed. And then this model is used to select the optimum process parameters to obtain the desired welding quality. The verification test results demonstrate that the method presented in this paper to optimize the welding parameters and enhance the welding performance is effective and feasible in the SSRSW process.

关键词： Small scale resistance spot welding Response surface methodology multi-objective optimization method Signal-to-noise ratio Principal component analysis Titanium alloy

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optimization of gaseous working fluid and internally finned absorber tube for enhancing the thermal performance of parabolic trough solar collector

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APPLIED THERMAL ENGINEERING 2024年 239卷

作者： Anand, Sumeet Kumar, Sumit Natl Inst Technol Dept Mech Engn Rourkela 769008 Odisha India

The current study examined the effect of various types of longitudinal finned absorber tubes with the gaseous working fluid on the performance of the parabolic trough collector. Conventional heat transfer fluids, such as water, thermal oils, molten salts, etc., have been limited when the parabolic trough collector works at very high temperatures. Gas may be used as heat transfer fluid when this collector may operate at very high temperatures. However, the heat transfer coefficient of gas is smaller than the conventional heat transfer fluid. Therefore, fins may be used to improve the parabolic trough collector's thermal performance when gas is used as heat transfer fluid. Hence, selecting the best suitable gas as heat transfer fluid and the optimum fin structure is essential to improve this collector's thermal performance. In this context, the current study has considered seven different gases, namely air, carbon dioxide, helium, nitrogen, oxygen, methane, and neon, and six longitudinal finned absorber tubes with different profiles, namely, rectangular, triangular, trapezoidal, T-shaped, and Y-shaped to select the best suitable heat transfer fluid and optimum fin structure. The best suitable gas and optimum fin profile have been chosen based on specific criteria (multi-objective optimization technique or the performance enhancement factor index). This problem has been simulated using commercial software ANSYS Fluent 2020 R2. The experimental and numerical data discovered in the literature are used to validate the results of the current investigation and found in good accuracy between them. The methane gas is found to be the most suitable heat transfer fluid based on both criteria. Then, the effect of mass flow rate and inlet temperature of methane gas on the average friction factor and Nusselt number have been investigated. It is found that the average friction factor decreases with the mass flow rate for the given inlet temperature, while the opposite trend has been

关键词： Parabolic trough collector (PTC) Gases as heat transfer fluid (HTF) Longitudinal fins Performance enhancement factor (PEF) multi-objective optimization method Turbulent-flow Non-uniform heat flux (NUHF)

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Simplification and further optimization of spatial cable-truss structure without inner ring cables

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ENGINEERING COMPUTATIONS 2022年第6期39卷 2231-2255页

作者： Lu, Jian Xue, Suduo Liu, Renjie Li, Xiongyan Beijing Univ Technol Beijing Peoples R China Yantai Univ Yantai Peoples R China

Purpose In order to optimize SCSWIRC, the simplification and further optimization method is proposed. SCSWIRC's optimization includes two levels. The first level refers to simplifying structural system from the perspective of components;the second level refers to optimizing components' sectional areas from the perspective of mechanics. The first level aims to remove redundant components, and the second level aims to reduce structural self-weight based on the first level. The purpose of the paper is to simplify SCSWIRC's structural system and optimize structural self-weight and reduce construction forming difficulty. Design/methodology/approach Grid-jumping layout and multi-objective optimization method is used to simplify and further optimize Spatial cable-truss structure without inner ring cables (SCSWIRC). Grid-jumping layout is used to simplify remove redundant components, and multi-objective optimization method is used to reduce structural self-weight. The detailed solving process is given based on grid-jumping layout and multi-objective optimization method. Findings Take SCSWIRC with a span of 100m as an example to verify the feasibility and correctness of the simplification and further optimization method. The optimization results show that 12 redundant components are removed and the self-weight reduces by 3.128t from original scheme to grid-jumping layout scheme 1. The self-weight reduces from 36.007t to 28.231t and feasible coefficient decreases from 1.0 to 0.627 from grid-jumping layout scheme 1 to multi-objective optimization scheme. The simplification and further optimization can not only remove the redundant components and simplify structural system to reduce construction forming difficulty, but also optimize structural self-weight under considering structural stiffness to reduce project costs. Originality/value The proposed method firstly simplifies SCSWIRC and then optimizes the simplified SCSWIRC, which can solve the optimization problem from the pers

关键词： Spatial cable-truss structure without inner ring cables (SCSWIRC) Grid-jumping layout multi-objective optimization method Solution procedure

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multi-objective FUZZY OPTIMAL DESIGN OF ALPHA-BETA ESTIMATORS FOR NONLINEAR VARIABLE STRUCTURE CONTROL

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INTERNATIONAL JOURNAL OF INNOVATIVE COMPUTING INFORMATION AND CONTROL 2011年第5A期7卷 2123-2140页

作者： Lee, Ting-En Su, Juhng-Perng Yu, Ker-Wei Hsia, Kuo-Hsien Natl Yunlin Univ Sci & Technol Grad Sch Engn Sci & Technol Touliu 640 Yunlin Taiwan Natl Yunlin Univ Sci & Technol Dept Elect Engn Touliu 640 Yunlin Taiwan Oversea Chinese Univ Dept Informat Technol Taichung 407 Taiwan Natl Kaohsiung Marine Univ Dept Marine Engn Cijin 805 Kahsiung Taiwan Far E Univ Dept Management Informat Syst Tainan 744 Taiwan

Given a tracking control problem for a class of cascade-connected nonlinear systems, we integrate an optimal alpha-beta estimator with a newly variable structure controller to provide excellent tracking performance. The significant feature of the designed alpha-beta estimator is using a multi-objective fuzzy optimization method to obtain the optimal parameters such that the estimated signals can be applied in the feedback controller. In the controller design, we integrate a new hard variable structure control law with a fuzzy-based soft switching control law to achieve the tracking control. To illustrate the effectiveness of the design, the proposed methods are verified through an experimental apparatus, named twin rotor multi-input multi-output system (TRMS). The experimental results strongly suggest that the developed optimal alpha-beta estimator and newly variable structure controller are encouraging for practical applications.

关键词： Alpha-beta estimator multi-objective optimization method Fuzzy logic Tracking control Variable structure control Twin rotor MIMO system

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Output power control for hydro-viscous transmission based continuously variable speed wind turbine

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RENEWABLE ENERGY 2014年 72卷 395-405页

作者： Yin, Xiu-xing Lin, Yong-gang Li, Wei Liu, Hong-wei Gu, Ya-jing Zhejiang Univ State Key Lab Fluid Power Transmiss & Control Hangzhou 310027 Peoples R China

A hydro-viscous transmission based continuously variable speed wind turbine is proposed in this paper to smooth the output power fluctuations in the full-load region. The hydro-viscous transmission concept is based upon mature technology and is characterized by low production cost and high reliability. Torque characteristics and transmission efficiency of this type of wind turbine are analyzed. A particle swarm optimization algorithm based multi-objective optimization method is employed to optimally design the hydro-viscous transmission. Major components of the wind power system have been mathematically modeled and analyzed in detail. Furthermore, a hybrid output power control strategy is proposed and implemented to precisely control the generated power and torque for this system. This wind power system has been validated by a theoretical analysis and a comparative simulation study. The simulation results by using an actual detailed model show the achievement of quite satisfactory performances of smoothing power and torque fluctuations despite the varying wind speed. (c) 2014 Elsevier Ltd. All rights reserved.

关键词： Variable speed wind turbine Hydro-viscous transmission Transmission efficiency multi-objective optimization method Hybrid output power control strategy

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Improved Yangtze River Diversions: Are they helping to solve algal bloom problems in Lake Taihu, China?

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ECOLOGICAL ENGINEERING 2013年 51卷 104-116页

作者： Li, Yiping Tang, Chunyan Wang, Chao Anim, Desmond O. Yu, Zhongbo Acharya, Kumud Minist Educ Key Lab Integrated Regulat & Resource Dev Shallow Nanjing 210098 Jiangsu Peoples R China Hohai Univ Coll Environm Nanjing 210098 Jiangsu Peoples R China Univ Nevada Dept Geosci Las Vegas NV 89119 USA Desert Res Inst Las Vegas NV 89119 USA Kwame Nkrumah Univ Sci & Technol Coll Engn Kumasi Ghana State Key Lab Hydrol Water Resources & Hydraul En Nanjing 210098 Jiangsu Peoples R China

To mitigate eutrophication by enhancing water exchange in Lake Taihu, the third largest freshwater lake in China, a water transfer project was initiated in 2002. The project was designed to flush pollutants out of the lake by transferring water from the Yangtze River. However, the original Yangtze River Diversion did not significantly enhance water exchange in the Meiliang Bay, the most polluted area of Lake Taihu. To overcome this deficiency, the improved Yangtze River Diversions have been designed recently by adding two new pump stations named Meiliang and Xingou around Meiliang Bay. Effectiveness of water transfer projects was investigated in this study by using a three-dimensional hydrodynamic model, Environmental Fluid Dynamics Code (EFDC), based on the concept of water age. Model results showed that adding new pump stations significantly improved the effectiveness of Yangtze River Diversion in Meiliang Bay. Success of water transfer is also strongly associated with the inflow or outflow rate of water transfer projects and wind conditions. Southeastern winds which dominate in summer increase performance of water transfer and improve water exchanges in Meiliang Bay. Considering water age and cost, an economically effective influent flow rate from Wangyu River (the original Yangtze River Diversion) was predicted to be 120 m(3)/s, and the corresponding appropriate outflow rate from the Meiliang pump station was about 15-20 m(3)/s on the basis of multi-objective optimization method, which decreased the average water age in Meiliang Bay by 24.32% of the original Yangtze River Diversion. Adding Xingou pump station had the similar contribution to reducing the water age in Meiliang Bay as the Meiliang pump station. In general, the improved Yangtze River Diversions played a supplementary role for the original Yangtze River Diversion in solving algal bloom problems in Meiliang Bay. (C) 2012 Elsevier B.V. All rights reserved.

关键词： EFDC Eutrophication multi-objective optimization method Shallow lake Water age Water transfer

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DISCRETE ELEMENT-BASED optimization PARAMETERS OF AN EXPERIMENTAL CORN SILAGE CRUSHING AND THROWING DEVICE

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TRANSACTIONS OF THE ASABE 2021年第3期64卷 1019-1026页

作者： Bai, Shenghe Yang, Qizhi Niu, Kang Zhao, Bo Zhou, Liming Yuan, Yanwei Chinese Acad Agr Mechanizat Sci State Key Lab Soil Plant & Machine Syst Technol Beijing Peoples R China Jiangsu Univ Sch Agr Equipment Engn Zhenjiang Jiangsu Peoples R China

To improve the performance of a corn silage crushing and throwing device and address the problems of low crushing quality and high power consumption, a discrete element simulation model of a corn silage crushing and throwing device and granular straw was established based on discrete element theory using EDEM, a general-purpose CAE software program designed with modern discrete element model technology to simulate and analyze particle processing and production operations. The average cutting force and average energy loss of the particles were the evaluation indexes, and the influence of feed rate, crushing speed, and dial speed on the evaluation indexes was analyzed using single-factor simulation tests. The order of significance was crushing speed > feed rate > dial speed for the average cutting force and crushing speed > dial speed > feed rate for the average energy loss. Using multi-objective optimization, the optimal combination of feed rate, crushing speed, and dial speed was 3.52 kg s(-1), 892.06 rpm, and 1502 rpm, respectively. With the optimal parameters, the average cutting force was 58.20 N and the average energy loss was 0.85 J. To verify the feasibility of the EDEM simulation, field tests were conducted using a trial-produced device, with the acceptability of straw crushing and power consumption as the test indicators. During the field tests, the feed rate, crushing speed, and dial speed were set to 3.52 kg s(-1), 890 rpm, and 1500 rpm, respectively. The field tests showed that the acceptability of straw crushing and the power consumption were 93.60% and 6.73 kW.h, respectively, with the optimal parameters, which satisfied the corn silage crushing standard and provides a theoretical and scientific basis for the design and optimization of the device.

关键词： Corn silage Crushing and throwing device Discrete element simulation Motion simulation multi-objective optimization method

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Specific cutting force and cutting condition interaction modeling for round insert face milling operation

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INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2016年第5-8期84卷 1705-1715页

作者： Ghorbani, Hamid Moetakef-Imani, Behnam Ferdowsi Univ Mashhad Fac Engn Dept Mech Engn Mashhad Iran

Face milling by round insert is currently one of the most common processes for roughing, semi-finishing, and finishing machining operations. Proper estimation and analysis of the round insert cutting forces play an important role in the process optimization. This paper presents a new method for identifying specific cutting force coefficients (SCFCs) for full immersion face milling with round inserts. At the first step, an inverse method is proposed to solve the mechanistic force model equations by non-dominated sorting genetic algorithm II (NSGA-II) which is one of the powerful multi-objective optimization methods. In addition, the artificial neural network (ANN) models are developed to predict the SCFCs in non-experimented conditions. Mean absolute percentage error values for the proposed ANN are between 1.7 and 10.1 % for training and testing which are satisfactory. In order to evaluate the efficiency of NSGA-II and ANN models, extensive experimental cutting force results are compared with those obtained with the proposed algorithm. The good accordance in the entire time of cutting edge engagement shows the validity of the developed methodology. Moreover, the interactions of cutting parameters, i.e., cutting speed, feed per tooth, and depth of cut (DOC) on variations of tangential and radial shearing coefficients (k(tc), k(rc)) of specific cutting force are thoroughly investigated. The results show that in addition to cutting conditions, the cutting edge geometry of round insert has a significant influence on k(tc) and k(rc) variations.

关键词： Specific cutting force coefficients (SCFCs) Face milling Round insert multi-objective optimization method Non-dominated sorting genetic algorithm II (NSGA-II) Artificial neural network (ANN)

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A rutting-based optimum maintenance decision strategy of hot in-place recycling in semi-rigid base asphalt pavement

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JOURNAL OF CLEANER PRODUCTION 2021年 297卷 126663-126663页

作者： Pan, Yuanyuan Liu, Guoqiang Tang, Dong Han, Dongdong Li, Xuanguo Zhao, Yongli Southeast Univ Sch Transportat Nanjing 211189 Jiangsu Peoples R China Changjiang Inst Survey Planning Design & Res Wuhan 430010 Hubei Peoples R China

Hot in-place recycling (HIR), 100% recycling reclaimed asphalt pavement (RAP) directly on a construction site, has been widely used as a sustainable maintenance treatment. Since the RAP provides aged asphalt and dense skeleton structure, the HIR is beneficial to restoring pavement rutting resistance. With ever-increasing maintenance requirements whereas limited maintenance budgets, a rutting-based optimum maintenance decision strategy of hot in-place recycling in semi-rigid base asphalt pavement is proposed. It contains the selection of maintenance sections using the peak cutting method in a multi-objective optimization model and the determination of maintenance timing by the arching depth rather than long-term pavement performance. To verify, a case study based on a HIR project of an existing expressway in Jiangsu Province in China is conducted. Results confirms the economy and effectiveness of the peak cutting method in selecting maintenance sections by comparison with the traditional empirical method. With the finite element simulation, the arching depth is proved as the dominant factor of the temperature of asphalt mixtures in milling process. Based on the confidence level of milling temperature, maintenance timing related threshold of arching depth are recommended. Consequently, the proposed maintenance decision strategy could provide the highway management department with guidance in selecting maintenance sections and determining maintenance timing at a critical pre-requisite of saving maintenance funds and restoring pavement serviceability. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Sustainable maintenance management Hot in-place recycling Rutting Maintenance section and maintenance timing multi-objective optimization method The peak cutting method

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Research on Operation optimization of Heating System Based on Electric Storage Coupled Solar Energy and Air Source Heat Pump

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Energy Engineering 2023年第9期120卷 1991-2011页

作者： Jingxiao Han Chuanzhao Zhang LuWang ZengjunChang Qing Zhao Ying Shi JiaruiWu Xiangfei Kong Technical Management Department Beijing District Heating Group Co.Ltd.Beijing100028China College of Biochemical Engineering Beijing Union UniversityBeijing100032China School of Energy and Environmental Engineering Hebei University of TechnologyTianjin300401China Technology Research and Development Department Beijing Heating Project Design Co.Ltd.Beijing100071China Digital Intelligence Technology Center China Railway Group Mechanical and Electrical Installation Co.Ltd.Beijing100049China

For heating systems based on electricity storage coupled with solar energy and an air source heat pump(ECSA),choosing the appropriate combination of heat sources according to local conditions is the key to improving economic *** this paper,four cities in three climatic regions in China were selected,namely Nanjing in the hot summer and cold winter region,Tianjin in the cold region,Shenyang and Harbin in the severe cold winter *** levelized cost of heat(LCOH)was used as the economic evaluation index,and the energy consumption and emissions of different pollutants were *** software was used to simulate and analyze the system *** Hooke-Jeeves optimization algorithm and GenOpt software were used to optimize the system *** results showed that ECSA systemhad an excellent operation effect in cold region and hot summer and cold winter *** with ECS system,the systemenergy consumption,and the emission of different pollutants of ECSA system can be reduced by a maximum of 1.37 *** cold region,the initial investment in an air source heat pump is higher due to the lower ambient temperature,resulting in an increase in the LOCH value of ECSA *** the LOCH value of ECSA system in each region was optimized,the heating cost of the system was reduced,but also resulted in an increase in energy consumption and the emission of different pollutant gases.

关键词： Electric heat storage solar energy air source heat pump multi-objective optimization method LOCH

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