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A Multiscale Reliability-Based Design Optimization Method for Carbon-Fiber-Reinforced Composite Drive Shafts
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作者 Huile Zhang Shikang Li +3 位作者 Yurui Wu Pengpeng Zhi Wei Wang Zhonglai Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1975-1996,共22页
Carbon fiber composites,characterized by their high specific strength and low weight,are becoming increasingly crucial in automotive lightweighting.However,current research primarily emphasizes layer count and orienta... Carbon fiber composites,characterized by their high specific strength and low weight,are becoming increasingly crucial in automotive lightweighting.However,current research primarily emphasizes layer count and orientation,often neglecting the potential of microstructural design,constraints in the layup process,and performance reliability.This study,therefore,introduces a multiscale reliability-based design optimization method for carbon fiber-reinforced plastic(CFRP)drive shafts.Initially,parametric modeling of the microscale cell was performed,and its elastic performance parameters were predicted using two homogenization methods,examining the impact of fluctuations in microscale cell parameters on composite material performance.A finite element model of the CFRP drive shaft was then constructed,achieving parameter transfer between microscale and macroscale through Python programming.This enabled an investigation into the influence of both micro and macro design parameters on the CFRP drive shaft’s performance.The Multi-Objective Particle Swarm Optimization(MOPSO)algorithm was enhanced for particle generation and updating strategies,facilitating the resolution of multi-objective reliability optimization problems,including composite material layup process constraints.Case studies demonstrated that this approach leads to over 30%weight reduction in CFRP drive shafts compared to metallic counterparts while satisfying reliability requirements and offering insights for the lightweight design of other vehicle components. 展开更多
关键词 Multiscale reliability-based design optimization carbon-fabric-reinforced composite drive shaft
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Optimal Design of the Modular Joint Drive Train for Enhancing Cobot Load Capacity and Dynamic Performance
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作者 Peng Li Zhenguo Nie +1 位作者 Zihao Li Xinjun Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期26-40,共15页
Automation advancements prompts the extensive integration of collaborative robot(cobot)across a range of industries.Compared to the commonly used design approach of increasing the payload-to-weight ratio of cobot to e... Automation advancements prompts the extensive integration of collaborative robot(cobot)across a range of industries.Compared to the commonly used design approach of increasing the payload-to-weight ratio of cobot to enhance load capacity,equal attention should be paid to the dynamic response characteristics of cobot during the design process to make the cobot more flexible.In this paper,a new method for designing the drive train parameters of cobot is proposed.Firstly,based on the analysis of factors influencing the load capacity and dynamic response characteristics,design criteria for both aspects are established for cobot with all optimization design criteria normalized within the design domain.Secondly,with the cobot in the horizontal pose,the motor design scheme is discretized and it takes the joint motor diameter and gearbox speed ratio as optimization design variables.Finally,all the discrete values of the optimization objectives are obtained through the enumeration method and the Pareto front is used to select the optimal solution through multi-objective optimization.Base on the cobot design method proposed in this paper,a six-axis cobot is designed and compared with the commercial cobot.The result shows that the load capacity of the designed cobot in this paper reaches 8.4 kg,surpassing the 5 kg load capacity commercial cobot which is used as a benchmark.The minimum resonance frequency of the joints is 42.70 Hz. 展开更多
关键词 Multi-objective optimization Modular joint drive train design Load capacity Dynamic response performance
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Research on the Mechanism of Multi-Sensor Fusion Configuration Based on the Optimal Principle of the Vehicle
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作者 Zhao Binggen Zeng Dong +2 位作者 Lin Haoyu Qiu Xubo Hu Pijie 《汽车技术》 CSCD 北大核心 2024年第10期28-37,共10页
In order to address the issue of sensor configuration redundancy in intelligent driving,this paper constructs a multi-objective optimization model that considers cost,coverage ability,and perception performance.And th... In order to address the issue of sensor configuration redundancy in intelligent driving,this paper constructs a multi-objective optimization model that considers cost,coverage ability,and perception performance.And then,combining a specific set of parameters,the NSGA-II algorithm is used to solve the multi-objective model established in this paper,and a Pareto front containing 24 typical configuration schemes is extracted after considering empirical constraints.Finally,using the decision preference method proposed in this paper that combines subjective and objective factors,decision scores are calculated and ranked for various configuration schemes from both cost and performance preferences.The research results indicate that the multi-objective optimization model established in this paper can screen and optimize various configuration schemes from the optimal principle of the vehicle,and the optimized configuration schemes can be quantitatively ranked to obtain the decision results for the vehicle under different preference tendencies. 展开更多
关键词 Multi-sensor fusion Intelligent driving Multi-objective optimization Vehicle optimization
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Long-term operation optimization of circulating cooling water systems under fouling conditions
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作者 Jiarui Liang Yong Tian +3 位作者 Shutong Yang Yong Wang Ruiqi Yin Yufei Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期255-267,共13页
Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optim... Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering fouling.However,low flow velocity promotes fouling.Therefore,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term operation.This study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this goal.The model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and fouling.By optimizing the concentration cycle of the CCWS,water conservation and fouling control can be achieved.The model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance coefficient.Sensitivity experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation decrease.In periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling rate.Overall,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization. 展开更多
关键词 Computer simulation Circulating water system FOULING Concentration cycle optimIZATION Variable frequency drive
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A Loss-model-based Efficiency Optimization Control Method for Induction Traction System of High-speed Train under Emergency Self-propelled Mode
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作者 Yutong Zhu Yaohua Li 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期227-239,共13页
Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link v... Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link voltage and the traction power of the motor are significantly reduced, resulting in decreased traction efficiency due to the low load and low speed operations. Aiming to tackle this problem, a novel efficiency improved control method is introduced to the emergency mode of high-speed train traction system in this paper. In the proposed method, a total loss model of induction motor considering the behaviors of both iron and copper loss is established. An improved iterative algorithm with decreased computational burden is then introduced, resulting in a fast solving of the optimal flux reference for loss minimization at each control period. In addition, considering the parameter variation problem due to the low load and low speed operations, a parameter estimation method is integrated to improve the controller's robustness. The effectiveness of the proposed method on efficiency improvement at low voltage and low load conditions is demonstrated by simulated and experimental results. 展开更多
关键词 Efficiency optimization Induction motor Loss model control Motor drives Traction system
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Driving fatigue fusion detection based on T-S fuzzy neural network evolved by subtractive clustering and particle swarm optimization 被引量:6
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作者 孙伟 张为公 +1 位作者 李旭 陈刚 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期356-361,共6页
In order to improve the accuracy and reliability of the driving fatigue detection based on a single feature, a new detection algorithm based on multiple features is proposed. Two direct driver's facial features refle... In order to improve the accuracy and reliability of the driving fatigue detection based on a single feature, a new detection algorithm based on multiple features is proposed. Two direct driver's facial features reflecting fatigue and one indirect vehicle behavior feature indicating fatigue are considered. Meanwhile, T-S fuzzy neural network(TSFNN)is adopted to recognize the driving fatigue of drivers. For the structure identification of the TSFNN, subtractive clustering(SC) is used to confirm the fuzzy rules and their correlative parameters. Moreover, the particle swarm optimization (PSO)algorithm is improved to train the TSFNN. Simulation results and experiments on vehicles show that the proposed algorithm can effectively improve the convergence speed and the recognition accuracy of the TSFNN, as well as enhance the correct rate of driving fatigue detection. 展开更多
关键词 driving fatigue fusion detection particle swarm optimization(PSO) subtractive clustering(SC)
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Optimal Design of a Main Driving Mechanism for Servo Punch Press Based on Performance Atlases 被引量:7
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作者 ZHOU Yanhua XIE Fugui LIU Xinjun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第5期909-917,共9页
The servomotor drive turret punch press is attracting more attentions and being developed more intensively due to the advantages of high speed,high accuracy,high flexibility,high productivity,low noise,cleaning and en... The servomotor drive turret punch press is attracting more attentions and being developed more intensively due to the advantages of high speed,high accuracy,high flexibility,high productivity,low noise,cleaning and energy saving.To effectively improve the performance and lower the cost,it is necessary to develop new mechanisms and establish corresponding optimal design method with uniform performance indices.A new patented main driving mechanism and a new optimal design method are proposed.In the optimal design,the performance indices,i.e.,the local motion/force transmission indices ITI,OTI,good transmission workspace good transmission workspace(GTW) and the global transmission indices GTIs are defined.The non-dimensional normalization method is used to get all feasible solutions in dimensional synthesis.Thereafter,the performance atlases,which can present all possible design solutions,are depicted.As a result,the feasible solution of the mechanism with good motion/force transmission performance is obtained.And the solution can be flexibly adjusted by designer according to the practical design requirements.The proposed mechanism is original,and the presented design method provides a feasible solution to the optimal design of the main driving mechanism for servo punch press. 展开更多
关键词 servo punch press main driving mechanism dimensional optimization transmission index performance atlas
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Cloud Computing Based Optimal Driving for a Parallel Hybrid Electric Vehicle 被引量:2
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作者 Jie Fan Yuan Zou +1 位作者 Zehui Kong Ludger Heide 《Journal of Beijing Institute of Technology》 EI CAS 2019年第1期155-161,共7页
A cloud computing based optimal driving method is proposed and its feasibility is validated through a real-world scenario simulation.Based on principles of vehicle dynamics,the driving optimization problem has been fo... A cloud computing based optimal driving method is proposed and its feasibility is validated through a real-world scenario simulation.Based on principles of vehicle dynamics,the driving optimization problem has been formulated into an optimal control problem constrained by traffic rules,directed at achieving lower equivalent fuel consumption and shorter travel time.In order to conveniently specify the constraints and facilitate the application of the dynamic programming(DP)algorithm,the driving optimization problem is transformed into spatial domain and discretized properly.Considering the heavy computational costs of the DP algorithm,a cloud computing based platform structure is proposed to solve the optimal driving problem in real-time.A case study is simulated based on a real-world traffic scenario in Matlab.Simulation results demonstrate that the cloud computing framework is promising toward realizing the real-time energy management for hybrid electric vehicles. 展开更多
关键词 hybrid ELECTRIC VEHICLE CLOUD COMPUTING optimAL driving energy management
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Optimization and Performance Comparison of Hairpin?Winding PMSM for Electric Vehicles Under Drive Cycle 被引量:1
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作者 LIU Huijuan SONG Tengfei +1 位作者 DU Jinwen LIU Bo 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第5期713-725,共13页
Aiming at the problem of large AC copper loss caused by skin effects and proximity effects,and low efficiency at high speed of the hairpin-winding permanent magnet synchronous motor(PMSM)for electric vehicles(EVs),thi... Aiming at the problem of large AC copper loss caused by skin effects and proximity effects,and low efficiency at high speed of the hairpin-winding permanent magnet synchronous motor(PMSM)for electric vehicles(EVs),this paper firstly established the electromagnetic analytical model of the hairpin winding to calculate AC resistance.And the finite element model(FEM)of the hairpin-winding driving motor is established to calculate the AC characteristic of the hairpin winding at different speeds and temperatures.Then,combining modified particle swarm optimization(MPSO)and FEM,a 60 k W hairpin-winding PMSM is optimized under driving cycle conditions,and the electromagnetic performance and heat dissipation performance are compared with that of the traditional strand-winding motor.Finally,a prototype is made and an experimental platform is built to test the efficiency Map and temperature rise of the hairpin-winding motor over the whole speed range and verify the accuracy of the proposed optimization design method.The results show that the hairpin-winding PMSM not only has higher slot filling rate,high?efficiency range and power density,but also has better heat dissipation performance,which is suitable for application in the field of electric vehicles. 展开更多
关键词 electric vehicles(EVs) hairpin-winding optimization design drive cycle performance comparison
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Robust Multiobjective and Multidisciplinary Design Optimization of Electrical Drive Systems 被引量:3
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作者 Gang Lei Tianshi Wang +1 位作者 Jianguo Zhu Youguang Guo 《CES Transactions on Electrical Machines and Systems》 2018年第4期409-416,共8页
Design and optimization of electrical drive systems often involve simultaneous consideration of multiple objectives that usually contradict to each other and multiple disciplines that normally coupled to each other.Th... Design and optimization of electrical drive systems often involve simultaneous consideration of multiple objectives that usually contradict to each other and multiple disciplines that normally coupled to each other.This paper aims to present efficient system-level multiobjective optimization methods for the multidisciplinary design optimization of electrical drive systems.From the perspective of quality control,deterministic and robust approaches will be investigated for the development of the optimization models for the proposed methods.Meanwhile,two approximation methods,Kriging model and Taylor expansion are employed to decrease the computation/simulation cost.To illustrate the advantages of the proposed methods,a drive system with a permanent magnet synchronous motor driven by a field oriented control system is investigated.Deterministic and robust Pareto optimal solutions are presented and compared in terms of several steady-state and dynamic performances(like average torque and speed overshoot)of the drive system.The robust multiobjective optimization method can produce optimal Pareto solutions with high manufacturing quality for the drive system. 展开更多
关键词 Electrical drive systems electrical machines multidisciplinary design optimization multiobjective optimization robust design optimization
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OPTIMAL TRACK SEEKING CONTROL OF DUAL-STAGE ACTUATOR FOR HIGH DENSITY HARD DISK DRIVES
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作者 Zhou Haomiao Wang Jie Zhou Youhe Zheng Xiaojing 《Acta Mechanica Solida Sinica》 SCIE EI 2006年第4期297-306,共10页
Based on generalized the variation method, by introducing Hamilton function and Lagrange multiplier, this paper proposed a linear quadratic optimal control strategy for an incomplete controllable system with fixed ter... Based on generalized the variation method, by introducing Hamilton function and Lagrange multiplier, this paper proposed a linear quadratic optimal control strategy for an incomplete controllable system with fixed terminal state and time. Applying the proposed optimal control to the simple two-input dual-stage actuator magnetic head positioning system with three degrees-of-freedom, the simulation results show that the system has no residual vibration at the terminal position and time, which can reduce the total access time during head positioning process. To verify the validation of the optimal control strategy of three degrees-of-freedom spring-mass models in actual magnetic head positioning of hard disk drives, a finite element model of an actual magnetic head positioning system is presented. Substituting the optimal control force from simple three degrees-of-freedom spring-mass models into the finite element model, the simulation results show that the magnetic head also has no residual vibration at the end of track-to-track travel. That is to say, the linear quadratic optimal control technique based on simple two-input dual- stage actuator system with three degrees-of-freedom proposed in this paper is of high reliability for the industrial application of an actual magnetic head positioning system. 展开更多
关键词 hard disk drives optimal track seeking control generalized variation method residual vibrationless
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A New Energy Optimal Control Scheme for a Separately Excited DC Motor Based Incremental Motion Drive
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作者 Milan A. Sheta Vivek Agarwal Paluri S. V. Nataraj 《International Journal of Automation and computing》 EI 2009年第3期267-276,共10页
This paper considers minimization of resistive and frictional power dissipation in a separately excited DC motor based incremental motion drive (IMD). The drive is required to displace a given, fixed load through a ... This paper considers minimization of resistive and frictional power dissipation in a separately excited DC motor based incremental motion drive (IMD). The drive is required to displace a given, fixed load through a definite angle in specified time, with minimum energy dissipation in the motor windings and minimum frictional losses. Accordingly, an energy optimal (EO) control strategy is proposed in which the motor is first accelerated to track a specific speed profile for a pre-determined optimal time period. Thereafter, both armature and field power supplies are disconnected, and the motor decelerates and comes to a halt at the desired displacement point in the desired total displacement time. The optimal time period for the initial acceleration phase is computed so that the motor stores just enough energy to decelerate to the final position at the specified displacement time. The parameters, such as the moment of inertia and coefficient of friction, which depend on the load and other external conditions, have been obtained using system identification method. Comparison with earlier control techniques is included. The results show that the proposed EO control strategy results in significant reduction of energy losses compared to the existing ones. 展开更多
关键词 Energy optimal control speed profile incremental motion drive (IMD).
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Optimum Structural Design of a Chain-Driving Pumping Unit
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作者 Zhang Ailin and Liu Yang(Doctors,Qinhuangdao Branch of Daqing Petroleum Institute) 《China Oil & Gas》 CAS 1994年第4期45-47,共3页
In this paper the pumping unit of type QLCJ14-6 is studied.Through the belt driving unit,the mo-tor drives the driving sprocket in which the rotation rate has been reduced by the reduction ge arbox.The locus chain mov... In this paper the pumping unit of type QLCJ14-6 is studied.Through the belt driving unit,the mo-tor drives the driving sprocket in which the rotation rate has been reduced by the reduction ge arbox.The locus chain moves between the driving sprocket and upper sprocket which are vertically set.There's a special chain element in the locus chain,which drives the reciprocating holster with the main shaft linchpin and slide block.The r reciprocating g holster could only move up and down when the locus chain moves in a circle.In this way the up and down stroke of the sucker rod and the mac hine is realized.The lower end of the reciprocating holster is con-nected with the equilibrium system to make the structure balance.The balancing cylinder is re-placed by the balancing block to make the structure simplified. 展开更多
关键词 CHAIN DRIVE PUMPING UNIT STRUCTURAL design optimization
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Optimization and implementation strategy of ESCO driving force in the development of energy-saving transformation market of existing buildings
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作者 GUO Han-ding DU Zhuang +1 位作者 LI Bai-tong ZHANG Yin-xian 《Ecological Economy》 2021年第4期301-314,共14页
The development of the existing building energy-saving transformation market is inseparable from the internal driving force of ESCO.Giving full play to the driving role of ESCO scientifically is the internal requireme... The development of the existing building energy-saving transformation market is inseparable from the internal driving force of ESCO.Giving full play to the driving role of ESCO scientifically is the internal requirement to promote the healthy and orderly operation of the existing building energy-saving transformation market.This paper summarizes the practical experience of developing ESCO driving force operation in foreign existing building energy-saving transformation market,analyzes the bottleneck of developing ESCO driving force operation in China’s existing building energy-saving transformation market,and puts forward useful practical enlightenment based on the comparison between home and abroad;According to the optimization principle of ESCO driving force operation in the development of existing building energy-saving transformation market,the optimization design framework of ESCO driving force is proposed,and the implementation strategy of ESCO driving force optimization in the development of existing building energy-saving transformation market is planned.In order to optimize and improve the effectiveness of the operation and development of the energy-saving transformation market of existing buildings with the internal driving force of ESCO. 展开更多
关键词 energy-saving transformation of existing buildings market development ESCO driving force optimization design implementation strategy
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Design and Optimization of Comb Drive Accelerator for High Frequency Oscillation
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作者 Zichen Zhang 《Modern Mechanical Engineering》 2018年第1期1-10,共10页
Comb-drive devises have been widely applied in many fields. However, the application of high frequency sensor, such as rocket chamber, still remains problems. In this work, a finite element code was used for the desig... Comb-drive devises have been widely applied in many fields. However, the application of high frequency sensor, such as rocket chamber, still remains problems. In this work, a finite element code was used for the design, optimization and visualization of a comb drive accelerator. In the simulation results, the post-optimization design has high performance in high frequency oscillation operating environment. The optimization is based on the ideal eigenfrequency and Nelder-Mead method. The 3-D working conditions are realized by testing and comparing the time and frequency domain of pre-optimized and optimized design whose frequency ranges from 2000 Hz to 5000 Hz. Finally, the electric potential and capacitance in comb drive are visualized, which shows the better electric signals and displacements. 展开更多
关键词 Comb-Drive MICRO-STRUCTURE COMSOL MULTIPHYSICS optimization Electric RESPONSES
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Modeling and Control of Parallel Hybrid Electric Vehicle Using Sea-Lion Optimization
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作者 J.Leon Bosco Raj M.Marsaline Beno 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期1441-1454,共14页
This paper develops a parallel hybrid electric vehicle(PHEV)propor-tional integral controller with driving cycle.To improve fuel efficiency and reduce hazardous emissions in hybrid electric vehicles(HEVs)combine an ele... This paper develops a parallel hybrid electric vehicle(PHEV)propor-tional integral controller with driving cycle.To improve fuel efficiency and reduce hazardous emissions in hybrid electric vehicles(HEVs)combine an electric motor(EM),a battery and an internal combustion engine(ICE).The electric motor assists the engine when accelerating,driving longer highways or climbing hills.This enables the use of a smaller,more efficient engine.It also makes use of the concept of regenerative braking to maximize energy efficiency.In a Hybrid Electric Vehicle(HEV),energy dissipated while braking is utilized to charge the battery.The proportional integral controller was used in this paper to analyze engine,motor performance and the New European Driving Cycle(NEDC)was used in the vehicle driving test using Matlab/Simulink.The proportional integral controllers were designed to track the desired vehicle speed and manage the vehi-cle’s energyflow.The Sea Lion Optimization(SLnO)methods were created to reduce fuel consumption in a parallel hybrid electric vehicle and the results were obtained for the New European Driving Cycle. 展开更多
关键词 Hybrid electric vehicle(HEV) proportional integral controller parallel HEV fuel efficiency new European driving cycle(NEDC) sea lion optimization(SLnO)
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系统观念视域下思想政治教育高质量发展的动力优化 被引量:2
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作者 王燕 《上海理工大学学报(社会科学版)》 2024年第2期165-171,共7页
新时代新征程要推进思想政治教育高质量发展,持久有效的动力至关重要。运用系统观念对思想政治教育高质量发展的动力结构进行科学审视,找准思想政治教育发展与国家战略、个人需求、自身变革的矛盾切入点。通过对动力主体、动力目标、动... 新时代新征程要推进思想政治教育高质量发展,持久有效的动力至关重要。运用系统观念对思想政治教育高质量发展的动力结构进行科学审视,找准思想政治教育发展与国家战略、个人需求、自身变革的矛盾切入点。通过对动力主体、动力目标、动力传输、动力评估进行科学系统整体分析,厘清推动思想政治教育高质量发展的动力运行机理。从内生、外源、共生三重维度,激活内源生产力、增强外驱牵引力、整合协同推动力,化“压力”“阻力”为强劲“动力”,实现思想政治教育高质量发展系统动力的整体涌现。 展开更多
关键词 系统观念 高质量发展 动力优化
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基于优化地理探测器的生态环境质量驱动力分析 被引量:1
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作者 牟凤云 黄淇 陈林 《水土保持研究》 CSCD 北大核心 2024年第1期440-449,共10页
[目的]克服生态环境质量(EQI)演化驱动因子在离散化过程中的随机性和主观性,优化传统地理探测器。[方法]利用相等间隔法、分位数法、自然断点法、几何间隔法和标准差法5种离散方法,对重庆市22项EQI演化驱动因子进行离散化,并结合地理探... [目的]克服生态环境质量(EQI)演化驱动因子在离散化过程中的随机性和主观性,优化传统地理探测器。[方法]利用相等间隔法、分位数法、自然断点法、几何间隔法和标准差法5种离散方法,对重庆市22项EQI演化驱动因子进行离散化,并结合地理探测器确定各因子的合理离散法与分类数,从而探究各驱动因子的驱动力大小和各驱动因子间交互模式。[结果](1)2005—2020年重庆市EQI处于I、Ⅲ和Ⅳ级的区县数量占比减少0.211,处于Ⅱ和V级的区县数量占比上升0.211,总体呈下降趋势,在空间上呈由西北向东南走向的梯度分布特征。(2)研究中各离散方法适用性排序为:自然断点法>几何间隔法>分位数法>相等间隔法>标准差法。不同因子适用的离散方法各异,应根据因子数据特征择优选取离散方法。(3)识别出影响重庆市EQI演化的关键驱动因子4个(0.37~0.49),主要驱动因子13个(0.14~0.33)、次要驱动因子4个(0.05~0.13)和其他因子1个(0.04),各驱动因子间交互作用均为双重增强或非线性增强。[结论]合理的离散化可以一定程度上克服连续数据离散化过程中的随机性和主观性,从而优化重庆市EQI演化驱动力探测结果。 展开更多
关键词 合理离散法 地理探测器 生态环境质量 驱动力 重庆市
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基于模型预测的直驱式波浪发电机机侧最优功率控制技术 被引量:1
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作者 黄磊 魏莱 +1 位作者 杨建龙 胡敏强 《电工技术学报》 EI CSCD 北大核心 2024年第14期4391-4404,共14页
直驱式波浪发电系统具有结构简单、成本低、效率高等优点,得到了国内外学者的广泛关注。该文以直驱式波浪发电系统为研究对象,分析并建立了直驱式波浪发电装置的水动力数学模型和永磁直线电机的动态数学模型。推导了基于模型预测的功率... 直驱式波浪发电系统具有结构简单、成本低、效率高等优点,得到了国内外学者的广泛关注。该文以直驱式波浪发电系统为研究对象,分析并建立了直驱式波浪发电装置的水动力数学模型和永磁直线电机的动态数学模型。推导了基于模型预测的功率控制策略用于直驱式波浪发电系统。在功率控制策略中从功率捕获策略和功率跟踪控制策略展开研究以实现将波浪能转换为电能并汇入直流母线。重点围绕功率捕获策略开展基于模型预测控制技术研究,分别从控制策略、预测区间和成本函数三个角度分析了基于模型预测的最优功率捕获策略。建立了仿真模型并进行仿真分析,结果表明,采用基于模型预测的最优功率捕获策略可有效提高不规则波下发电机从波浪发电系统捕获能量。此外,采用以直流母线功率汇入最大为目标的成本函数可以有效地提高发电机输入直流侧能量,具有重要的实用价值。最后通过实验室模拟平台进行了实验测试。 展开更多
关键词 直驱式波浪发电 最优功率捕获 模型预测控制 功率跟踪控制
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基于数据驱动的范数最优迭代学习控制 被引量:1
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作者 许万 肖迪 陈婷薇 《湖北工业大学学报》 2024年第2期1-4,16,共5页
在系统模型确定的前提下,传统的范数最优迭代学习控制(NOILC)可以有效提高伺服系统的跟踪精度。但是在实际控制过程中,系统模型参数往往是变化的,从而导致控制器性能的下降。为此,提出了一种基于数据驱动的范数最优迭代学习控制方法。... 在系统模型确定的前提下,传统的范数最优迭代学习控制(NOILC)可以有效提高伺服系统的跟踪精度。但是在实际控制过程中,系统模型参数往往是变化的,从而导致控制器性能的下降。为此,提出了一种基于数据驱动的范数最优迭代学习控制方法。以系统的输入输出为依据,建立系统估计模型的代价函数,对代价函数进行偏微分处理,得到一种基于数据驱动的非参数模型辨识方法,最后将此模型辨识方法和NOILC相结合。实验结果表明:针对时变系统,此控制方法的跟踪误差为NOILC(Norm optimal iterative learning control,NOILC)的57.1%,并且相比NOILC提前5次收敛。因此,提出的方法能有效改善时变系统的跟踪性能。 展开更多
关键词 迭代学习 数据驱动 范数最优 运动控制
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