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Multi-objective Stability Control Algorithm of Heavy Tractor Semi-trailer Based on Differential Braking 被引量:13
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作者 ZONG Changfu ZHU Tianjun +1 位作者 WANG Chang LIU Haizhen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第1期88-97,共10页
Rollover and jack-knifing of tractor semi-trailer are serious threats for vehicle safety, and accordingly active safety technologies have been widely used to reduce or prevent the occurrence of such accidents. However... Rollover and jack-knifing of tractor semi-trailer are serious threats for vehicle safety, and accordingly active safety technologies have been widely used to reduce or prevent the occurrence of such accidents. However, currently tractor semi-trailer stability control is generally only a single hazardous condition (rollover or jack-knifing) control, it is difficult to ensure the vehicle comprehensive stability of various dangerous conditions. The main objective of this study is to introduce a multi-objective stability control algorithm which can improve the vehicle stability of a tractor semi-trailer by using differential braking. A vehicle controller is designed to minimize the likelihood of rollover and jack-knifing. First a linear vehicle model of tractor semi-trailer is constructed. Then an optimal yaw control for tractor using differential braking is applied to minimize the yaw rate and lateral acceleration deviation of tractor, as well as the hitch articulation angle of tractor semi-trailer, so as to improve the vehicle stability. Second a braking scheme and variable structure control with sliding mode control are introduced in order to achieve the best braking effect. Last Fishhook maneuver is introduced to the active safety simulation and the active control system effect verification. The simulation results show that multi-objective stability control algorithm of semi-trailer could improve the vehicle stability significantly during the transient maneuvers. The proposed multi-objective stability control algorithm is effective to prevent the vehicle rollover and jackknifing. 展开更多
关键词 ROLLOVER jack-knifing tractor semi-trailer multi-objective stability control
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Design for aircraft engine multi-objective controllers with switching characteristics 被引量:3
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作者 Liu Xiaofeng Shi Jing +1 位作者 Qi Yiwen Yuan Ye 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第5期1097-1110,共14页
The aircraft engine multi-loop control system is described and the switching control theory is introduced to solve the regulating and protecting control problems in this paper. The aircraft engine multi-loop control s... The aircraft engine multi-loop control system is described and the switching control theory is introduced to solve the regulating and protecting control problems in this paper. The aircraft engine multi-loop control system is firstly described and the control problems are formulated. Secondly, the theory of the smooth switching control is devoted and a new extended scheme for the smooth switching of a switched control system is introduced. Then, for the key technologies of aero-engines switching control, a design algorithm is presented which can determine which candidate controller should be put in feedback with the plant to achieve a desired performance and the procedure to design the aircraft engine multi-loop control system is detailed. The switching performance objectives and the switching scheme are given and a family of PID controllers and compensators is designed. The simulation shows that using the switching control design method can not only improve the dynamic performance of the aircraft engine control system and reduce the switching times, but also guarantee the stability in some peculiar occasions. 展开更多
关键词 Aircraft engine Compensatory controller Min/Max switching Multi-objectives control Smooth switching Switching scheme
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Design andtwo-objective simultaneous optimization of torque controller for switched reluctance motor in electric vehicle 被引量:1
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作者 朱曰莹 赵桂范 +1 位作者 王大方 刘仕强 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第6期79-85,共7页
In order to reduce the torque ripple,increase the average torque and optimize the drive performance of the switched reluctance motor (SRM),the nonlinear dynamic model of SRM is established in the MATLAB /Simulink envi... In order to reduce the torque ripple,increase the average torque and optimize the drive performance of the switched reluctance motor (SRM),the nonlinear dynamic model of SRM is established in the MATLAB /Simulink environment.The effects of the turn-on and turn-off angles are investigated by the simulation results of the dynamic model,and the function is made among the rotor speed,turn-on angle and turn-off angle.To optimize the torque dynamic performance,the two-objective simultaneous optimization function is proposed by two weight factors.And the optimized turn-on and turn-off angles as functions of rotor speed are developed by using the simultaneous optimization method.Then the optimized torque controller is designed based on the optimized turn-on and turn-off angles.The simulation results show that the optimized torque controller designed in this paper can effectively reduce the torque ripple and increase the average torque,and optimize the torque dynamic performance of the SRM. 展开更多
关键词 electric vehicle switched reluctance motor torque controller two-objective simultaneous optimization
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The multi-objective optimal control with X-Q adaptive controller
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作者 Qing HU Yiju ZHAN 《控制理论与应用(英文版)》 EI 2009年第2期202-206,共5页
This paper proposes a new type of nonlinear controllers and a large phase angle allowance design method based on the multi-objective optimal control system. With the proposed method, the performance of the system beco... This paper proposes a new type of nonlinear controllers and a large phase angle allowance design method based on the multi-objective optimal control system. With the proposed method, the performance of the system becomes better than that of the original system. Then, an example of the radar servo system is designed with a large phase angle allowance multi-objective optimal design method. Finally, the performance based on computer simulation demonstrates that the multi-objective optimal system is superior to linear optimal systems. 展开更多
关键词 Adaptive controller Multi-objective optimal design Nonlinear controller Servo system
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A Brief Tour on Exotic Control Objectives in Robotics
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作者 Rafael Kelly Carmen Monroy 《Journal of Mechanics Engineering and Automation》 2018年第2期53-59,共7页
Formulation of control objectives is a key issue in automatic control systems design. Although at first sight the desired goal (control objective) of a control system seems to be a trivial and obvious matter, for... Formulation of control objectives is a key issue in automatic control systems design. Although at first sight the desired goal (control objective) of a control system seems to be a trivial and obvious matter, for effectiveness of some high level robotic tasks, unusual exotic control objectives may be required. This paper presents a review of some exotic control objectives useful in robotics, such as velocity field control objective and range control objective. The paper also proposes a novel confinement control objective. The usefulness of these exotic control objectives may appear in safe robot-human interaction and self-protection of robots against collisions. 展开更多
关键词 control objective ROBOT robot-human CONFINEMENT range velocity field TEFDA (total energy function with damping assignment) exotic.
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Performance Monitoring of the Data-driven Subspace Predictive Control Systems Based on Historical Objective Function Benchmark 被引量:3
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作者 王陆 李柠 李少远 《自动化学报》 EI CSCD 北大核心 2013年第5期542-547,共6页
关键词 预测控制系统 性能监控 数据驱动 子空间 历史 基准 监视控制器 目标函数
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Aircraft Landing Gear Control with Multi-Objective Optimization Using Generalized Cell Mapping 被引量:3
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作者 孙建桥 贾腾 +3 位作者 熊夫睿 秦志昌 吴卫国 丁千 《Transactions of Tianjin University》 EI CAS 2015年第2期140-146,共7页
This paper presents a numerical algorithm tuning aircraft landing gear control system with three objectives,including reducing relative vibration, reducing hydraulic strut force and controlling energy consumption. Sli... This paper presents a numerical algorithm tuning aircraft landing gear control system with three objectives,including reducing relative vibration, reducing hydraulic strut force and controlling energy consumption. Sliding mode control is applied to the vibration control of a simplified landing gear model with uncertainty. A two-stage generalized cell mapping algorithm is applied to search the Pareto set with gradient-free scheme. Drop test simulations over uneven runway show that the vibration and force interaction can be considerably reduced, and the Pareto optimum form a tight range in time domain. 展开更多
关键词 LANDING GEAR SLIDING mode control model uncertainty MULTI-objectIVE optimization GENERALIZED cellmapping
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A multi-objective optimal PID control for a nonlinear system with time delay 被引量:1
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作者 Furui Xiong Zhichang Qin +6 位作者 Carlos Hernndez Yousef Sardahi Yousef Narajani Wei Liang Yang Xue Oliver Schtze Jianqiao Sun 《Theoretical & Applied Mechanics Letters》 CAS 2013年第6期35-40,共6页
It is generally difficult to design feedback controls of nonlinear systems with time delay to meet time domain specifications such as rise time, overshoot, and tracking error. Furthermore, these time domain specificat... It is generally difficult to design feedback controls of nonlinear systems with time delay to meet time domain specifications such as rise time, overshoot, and tracking error. Furthermore, these time domain specifications tend to be conflicting to each other to make the control design even more challenging. This paper presents a cell mapping method for multi-objective optimal feedback control design in time domain for a nonlinear Duffing system with time delay. We first review the multi-objective optimization problem and its formulation for control design. We then introduce the cell mapping method and a hybrid algorithm for global optimal solutions. Numerical simulations of the PID control are presented to show the features of the multi-objective optimal design. @ 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi:10.1063/2.1306306] 展开更多
关键词 delayed control system multi-objective optimal design cell mapping method hybridalgorithm Pareto optimal
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Tufting Carpet Machine Information Model Based on Object Linking and Embedding for Process Control Unified Architecture
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作者 GUO Xiang CHI Xinfu SUN Yize 《Journal of Donghua University(English Edition)》 CAS 2021年第1期43-50,共8页
In view of the lack of research on the information model of tufting carpet machine in China,an information modeling method based on Object Linking and Embedding for Process Control Unified Architecture(OPC UA)framewor... In view of the lack of research on the information model of tufting carpet machine in China,an information modeling method based on Object Linking and Embedding for Process Control Unified Architecture(OPC UA)framework was proposed to solve the problem of“information island”caused by the differentiated data interface between heterogeneous equipment and system in tufting carpet machine workshop.This paper established an information model of tufting carpet machine based on analyzing the system architecture,workshop equipment composition and information flow of the workshop,combined with the OPC UA information modeling specification.Subsequently,the OPC UA protocol is used to instantiate and map the information model,and the OPC UA server is developed.Finally,the practicability of tufting carpet machine information model under the OPC UA framework and the feasibility of realizing the information interconnection of heterogeneous devices in the tufting carpet machine digital workshop are verified.On this basis,the cloud and remote access to the underlying device data are realized.The application of this information model and information integration scheme in actual production explores and practices the application of OPC UA technology in the digital workshop of tufting carpet machine. 展开更多
关键词 tufting carpet machine digital workshop information model object Linking and Embedding for Process control Unified Architecture(OPC UA) INTERCONNECTION
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Modelling and Multi-Objective Optimal Control of Batch Processes Using Recurrent Neuro-fuzzy Networks 被引量:2
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作者 Jie Zhang 《International Journal of Automation and computing》 EI 2006年第1期1-7,共7页
In this paper, the modelling and multi-objective optimal control of batch processes, using a recurrent neuro-fuzzy network, are presented. The recurrent neuro-fuzzy network, forms a "global" nonlinear long-range pre... In this paper, the modelling and multi-objective optimal control of batch processes, using a recurrent neuro-fuzzy network, are presented. The recurrent neuro-fuzzy network, forms a "global" nonlinear long-range prediction model through the fuzzy conjunction of a number of "local" linear dynamic models. Network output is fed back to network input through one or more time delay units, which ensure that predictions from the recurrent neuro-fuzzy network are long-range. In building a recurrent neural network model, process knowledge is used initially to partition the processes non-linear characteristics into several local operating regions, and to aid in the initialisation of corresponding network weights. Process operational data is then used to train the network. Membership functions of the local regimes are identified, and local models are discovered via network training. Based on a recurrent neuro-fuzzy network model, a multi-objective optimal control policy can be obtained. The proposed technique is applied to a fed-batch reactor. 展开更多
关键词 Optimal control batch processes neural networks multi-objective optimisation.
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Method of Designing Missile Controller Based on Multi-Objective Opti mization
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作者 林波 孟秀云 刘藻珍 《Journal of Beijing Institute of Technology》 EI CAS 2006年第2期152-155,共4页
A method of designing robust controller based on genetic algorithm is presented in order to overcome the drawback of manual modification and trial in designing the control system of missile. Specification functions wh... A method of designing robust controller based on genetic algorithm is presented in order to overcome the drawback of manual modification and trial in designing the control system of missile. Specification functions which reflect the dynamic performance in time domain and robustness in frequency domain are presented, then dynamic/static performance, control cost and robust stability are incorporated into a multi-objective optimization problem. Genetic algorithm is used to solve the problem and achieve the optimal controller directly. Simulation results show that the controller provides a good stability and offers a good dynamic performance in a large flight envelope. The results also validate the effectiveness of the method. 展开更多
关键词 controller design multi-objective optimization genetic algorithm
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Applying Object-oriented Simulation to the Development of FMS Control Software
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作者 吴祚宝 《High Technology Letters》 EI CAS 1995年第2期20-24,共5页
The approach of control software development based on simulation is discussed. A library of object classes for a flexible manufacturing system(FMS) simulation has been developed using the technology of object-oriented... The approach of control software development based on simulation is discussed. A library of object classes for a flexible manufacturing system(FMS) simulation has been developed using the technology of object-oriented programming. Using the library, the simulation software of a FMS which has the same manufacturing logic with the FMS control system can be easily constructed. A new approach in the development of FMS control software based on software reuse and an emulator of the blade FMS control system for testing control software have also been developed. 展开更多
关键词 FMS SIMULATION control object-ORIENTED PROGRAMMING
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一种新颖的无人机停机坪无线充电系统及其控制方法
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作者 黄雪松 彭铖 +4 位作者 于林 曾勇 高玥 马飞 林先其 《电讯技术》 北大核心 2025年第7期1144-1151,共8页
随着无人机技术的不断发展和低空经济的提出,越来越多的领域开始使用无人机代替人力,以此提高作业效率,降低安全风险。由于无人机电池容量有限,导致其作业时间和作业半径被大大缩短,进而限制了其应用场景。针对现有基于有线充电或换电... 随着无人机技术的不断发展和低空经济的提出,越来越多的领域开始使用无人机代替人力,以此提高作业效率,降低安全风险。由于无人机电池容量有限,导致其作业时间和作业半径被大大缩短,进而限制了其应用场景。针对现有基于有线充电或换电技术的无人机自动机场存在的诸如触点接触不良、机械结构复杂、成本高昂等问题,对基于无线充电技术的无人机停机坪系统进行了研究,主要包括无人机无线充电系统磁场分布与效率分析、无人机无线充电自动控制电路与异物检测功能研究,以及无人机地面站控制流程研究等。在此基础上,搭建了一套基于无线充电技术的无人机停机坪。该停机坪相比现有无人机自动机场,具有容忍一定偏移量的无人机无线充电、识别不同无人机受电端和异物检测等创新功能。经实测,整个系统充电稳定且与有线充电时长近似,停机坪整体质量相比下降50 kg,成本约为现有无人机自动机场的1/3,在多场景下均有应用潜力。 展开更多
关键词 无人机停机坪 无线充电技术 自动控制电路 异物检测 地面站控制 多场景应用
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不对称故障期间VSG电压源特性控制策略下的短路电流解析计算
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作者 王彤 何淑威 +5 位作者 魏玉文 郑煜超 王增平 徐潜 杨国生 王聪博 《电力自动化设备》 北大核心 2025年第10期201-209,224,共10页
电网发生不对称故障时,虚拟同步发电机(VSG)控制的故障暂态特性对提升继电保护在新能源并网系统中的适应性至关重要。为此,提出了一种在故障期间保持VSG电压源特性的优化控制策略,并解析推导了不对称故障期间VSG短路全电流解析表达式。... 电网发生不对称故障时,虚拟同步发电机(VSG)控制的故障暂态特性对提升继电保护在新能源并网系统中的适应性至关重要。为此,提出了一种在故障期间保持VSG电压源特性的优化控制策略,并解析推导了不对称故障期间VSG短路全电流解析表达式。分析了不对称故障期间VSG的故障暂态特性,建立了功角稳定和幅值切换的控制策略,以实现故障期间VSG的电压源特性。针对不对称故障场景,设计了一种基于正负双序电压电流双闭环的VSG控制,实现输出短路电流三相平衡、有功功率波动抑制等多目标协同控制。在此基础上,考虑VSG低电压穿越过程中虚拟阻抗控制以及正负双序电压电流双环控制的暂态响应特性,建立了虚拟内电势与输出正负序短路电流之间的函数关系,推导出不对称故障期间基于VSG电压源特性多目标协同控制的短路全电流解析表达式。利用MATLAB/Simulink仿真验证了所提VSG优化控制策略的有效性以及短路电流解析表达式的正确性。 展开更多
关键词 虚拟同步发电机 不对称故障 低电压穿越 多目标协同控制 短路电流解析
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锂电池回收工厂异物管控和降本措施浅谈
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作者 罗佳 刘勇 +3 位作者 周洋 崔俊葳 周成乾 陈雨阳 《化工设计通讯》 2025年第2期8-10,14,共4页
在锂电回收工厂设计阶段通过对产品和工艺产线的了解分析,细分各专业要求,在设备选购、土建和机电公辅配套方面防止金属异物的引入,降低建设成本,达到节能降本增效的目的。
关键词 锂电池回收工厂 金属异物 管控 降本
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三峡与清江梯级水库群协同防洪优化调度研究
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作者 赵辉 朱语欣 +3 位作者 刘园 黄斌 庞树森 黄迪 《长江科学院院报》 北大核心 2025年第8期76-83,93,共9页
针对复杂洪水地区组成下三峡与清江梯级水库协同防洪问题,选取三峡与清江流域的不同洪水地区组成作为调度模型输入,以上游防洪安全和下游防洪安全为目标,建立了三峡和清江梯级水库群多目标联合防洪优化调度模型,并采用NSGA-II算法进行... 针对复杂洪水地区组成下三峡与清江梯级水库协同防洪问题,选取三峡与清江流域的不同洪水地区组成作为调度模型输入,以上游防洪安全和下游防洪安全为目标,建立了三峡和清江梯级水库群多目标联合防洪优化调度模型,并采用NSGA-II算法进行求解。研究结果表明:1969年、1981年、1998年典型年设计洪水调度结果显示,相较三峡大洪水和清江大洪水情景,流域性大洪水情景下清江防洪库容投入时机更早;与实际调度方案相比,2020典型年的协调调度方案中,三峡调洪高水位降低了5.0 m,超额洪量减少了56.2亿m^(3),枝城、城陵矶的洪峰流量分别提高了2603、1035 m^(3)/s,三峡水库末水位降低了4.2 m,协同调度的防洪效益显著。 展开更多
关键词 防洪调度 防洪库容 多目标优化 三峡水库 清江梯级水库
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公共服务成本管控中的多元价值权衡:Q方法下的Z市地铁监管部门公职人员认知图谱
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作者 刘毅 菅一寒 《岳麓公共治理》 2025年第1期95-113,共19页
在公共服务成本管控中,监管部门公职人员对绩效目标的认知差异制约着管理效能。本研究聚焦绩效评估框架下公共服务的效率、质量与创新的协同优化机制,以Z市地铁运营成本年度审核为例,运用Q方法深入分析了来自不同监管部门的公职人员在... 在公共服务成本管控中,监管部门公职人员对绩效目标的认知差异制约着管理效能。本研究聚焦绩效评估框架下公共服务的效率、质量与创新的协同优化机制,以Z市地铁运营成本年度审核为例,运用Q方法深入分析了来自不同监管部门的公职人员在审核业务中的主观认知及其形成机制。通过刻画公职人员的认知图谱,发现受访者普遍将服务质量和用户体验置于首位,且在具体绩效目标的权衡中呈现出四种典型的成本管控偏好类型:强调智能化升级与人文关怀结合的技术-人文协同型、注重预算管理与资产配置的稳健-效能权衡型、重视安全保障与服务质量的安全-效能均衡型,以及强调人力资源投入与服务品质关联的福利-效能平衡型。这种多元目标导向凸显了公共服务优化过程中的系统复杂性,即成本管控机制设计中多重目标的均衡协调问题。研究结论为政策制定者构建多元目标平衡机制提供了实证依据,对推进公共服务改革具有重要的政策启示。 展开更多
关键词 成本管控 多元目标权衡 Q方法 地铁运营
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2025年中国经济形势展望与政策预期 被引量:2
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作者 刘伟 苏剑 《北京交通大学学报(社会科学版)》 北大核心 2025年第1期26-37,共12页
2024年中国GDP同比增长5.0%,经济运行“总体平稳、稳中有进”,顺利完成年初制定的5%左右增速目标。展望2025年,全国人口减少、市场预期偏弱、支柱产业调整、地缘政治风险、能源格局变动等国内外因素仍将影响中国经济发展。中国经济自然... 2024年中国GDP同比增长5.0%,经济运行“总体平稳、稳中有进”,顺利完成年初制定的5%左右增速目标。展望2025年,全国人口减少、市场预期偏弱、支柱产业调整、地缘政治风险、能源格局变动等国内外因素仍将影响中国经济发展。中国经济自然走势将是供给、需求双收缩的格局,且需求收缩大于供给,整体依然低于潜在水平。房地产风险、地方债务风险、汇率及货币风险、贸易摩擦风险等将成为未来中国经济发展的潜在风险点。鉴于此,2025年的政策目标仍需以需求端作为主要发力点,同时,对供给端的稳定运行和市场环境的持续改善提供必要的支持,宏观调控政策组合应该以需求、供给双扩张为主,以市场环境管理为辅。 展开更多
关键词 2025年经济展望 经济安全 自然走势 政策目标 宏观调控
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考虑周转率的多目标备件动态库存控制策略
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作者 杨华强 邱宇 +2 位作者 李源 曹蕾 夏唐斌 《制造业自动化》 2025年第3期77-86,共10页
合理的备件库存控制策略对制造企业稳定生产和经济效益产生直接影响,特别是对生产影响大、占用资金多的A类备件,此类备件往往提前期长、需求变化复杂。为此,提出了基于未来预测和历史需求的考虑成本、满足率和周转率的两个多目标备件动... 合理的备件库存控制策略对制造企业稳定生产和经济效益产生直接影响,特别是对生产影响大、占用资金多的A类备件,此类备件往往提前期长、需求变化复杂。为此,提出了基于未来预测和历史需求的考虑成本、满足率和周转率的两个多目标备件动态库存控制策略。通过某卷烟厂的真实数据验证证明,相比企业现存策略,对于需求发生时间不稳定且存在需求的时间较少的备件,基于未来预测的动态策略效果最好,各指标综合表现提升50.74%;而对于需求发生时间相对稳定的备件,基于历史需求的动态策略更具优越性,各指标综合表现提升4.31%。同时,对每个目标的权重进行敏感性分析。结果表明当满足率重要性提高时,应优先选择基于未来预测的动态策略,而当企业更关注总成本和周转率时,应考虑使用基于历史需求的动态策略。研究结果为制造企业在不同需求特征和不同的目标要求下选择合适的库存控制策略提供了重要的管理启示。 展开更多
关键词 备件管理 库存控制 动态策略 多目标优化
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手持控制器操作的上肢关节舒适性评估与作业优化研究
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作者 杨延璞 杨沁夏 +1 位作者 卓玥鸣 姬丽静 《西北工业大学学报》 北大核心 2025年第4期741-750,共10页
无人装备手持控制器的长时间操作易给作业人员带来上肢肌肉骨骼损伤风险,为提高手持控制器作业中人员的上肢关节舒适性,利用JACK人机工程分析软件进行数字人与作业场景建模,分别构建了关节力矩和角度的舒适度评估模型,研究了寰枕关节不... 无人装备手持控制器的长时间操作易给作业人员带来上肢肌肉骨骼损伤风险,为提高手持控制器作业中人员的上肢关节舒适性,利用JACK人机工程分析软件进行数字人与作业场景建模,分别构建了关节力矩和角度的舒适度评估模型,研究了寰枕关节不同前屈角度下的上肢关节舒适度变化关系,建立了手持控制器上肢姿态优化多目标函数,引入带精英策略的快速非支配排序遗传算法(nondominated sorting genetic algorithmⅡ,NSGA-Ⅱ)进行最优上肢姿态求解,获取手持控制器作业的最佳姿势并设计了辅助装置方案,进而引入直觉模糊数处理决策者在评估设计方案时的不确定与犹豫性,实现了最优姿态下手持控制器操作辅助装置设计方案优选。 展开更多
关键词 人机工效 上肢关节舒适性评估 多目标优化 直觉模糊数 手持控制器
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