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Optimization of Numerical Control Program and Machining Simulation Based on VERICUT 被引量:3
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作者 ZHOU Feng ZHANG Zixu +3 位作者 WU Chang TIAN Xin LIU Haotian HE Weidong 《Journal of Shanghai Jiaotong university(Science)》 EI 2019年第6期763-768,共6页
In the machining process of large-scale complex curved surface,workers will encounter problems such as empty stroke of tool,collision interference,and overcut or undercut of the workpieces.This paper presents a method... In the machining process of large-scale complex curved surface,workers will encounter problems such as empty stroke of tool,collision interference,and overcut or undercut of the workpieces.This paper presents a method for generating the optimized tool path,compiling and checking the numerical control(NC)program.Taking the bogie frame as an example,the tool paths of all machining surface are optimized by the dynamic programming algorithm,Creo software is utilized to compile the optimized computerized numerical control(CNC)machining program,and VERICUT software is employed to simulate the machining process,optimize the amount of cutting and inspect the machining quality.The method saves the machining time,guarantees the correctness of NC program,and the overall machining efficiency is improved.The method lays a good theoretical and practical foundation for integration of the similar platform. 展开更多
关键词 numerical control program bogie frame dynamic programming algorithm machining simulation VERICUT
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Pollution Control Programs of Large-Scale Livestock and Poultry Farms in the Dianchi Lake Basin 被引量:1
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作者 LI Zhong-jie ZHENG Yi-xin +1 位作者 XU Xiao-mei NI Jin-bi 《Animal Husbandry and Feed Science》 CAS 2011年第1期35-38,共4页
With the enlarging scale and intensifying production of livestock and poultry breeding, the environment pollution becomes increasingly prominent in the Dianchi Lake Basin since 1990s. According to the survey of "The ... With the enlarging scale and intensifying production of livestock and poultry breeding, the environment pollution becomes increasingly prominent in the Dianchi Lake Basin since 1990s. According to the survey of "The First National Census of Pollution Sources", occurrence and discharge of pollutants in large-scale livestock and poultry farms in this region were first understood. The pollution characteristics of large-scale live- stock and poultry breeding were also analyzed deeply. On this basis, the significance of pollution control programs for environment protection was investigated from aspects of pollution control policy, technology management and publicity. 展开更多
关键词 Dianchi Lake Basin Large-scale livestock and poultry breeding Pollution control program
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Safety control program for complex system based on behavior science
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作者 梁美健 杨光 陈大伟 《Journal of Coal Science & Engineering(China)》 2008年第4期578-580,共3页
To control complex system's safety effectively,safety control program was supported based on the principles of behavioral science that shapes organizational be- havior,and organizational behavior produced individu... To control complex system's safety effectively,safety control program was supported based on the principles of behavioral science that shapes organizational be- havior,and organizational behavior produced individual behavior.The program can be structured into a model that consists of three modules including individual behavior rectifi- cation,organization behavior diagnosis and model of safety culture.The research result not only reveals the deep cause of complex system accidents but also provides structural descriptions with the accidents cause. 展开更多
关键词 control program complex system behavior science accident cause
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Evaluation of a Voluntary Control Program for the Detection of Bovine Leukemia Virus Antibodies Based on Agar Gel Immunodiffusion Test in Dairy Farms in Costa Rica
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作者 Gaby Dolz Francine Huijsen +1 位作者 Carlos Jiménez Luis L. Rodríguez 《Open Journal of Veterinary Medicine》 2015年第12期229-233,共5页
Cattle from 20 dairy farms were serologically tested over a five-year period using agar gel immunodiffusion test (AGIDT) as part of a voluntary Bovine Leukemia Virus (BLV) control program. After five years of removing... Cattle from 20 dairy farms were serologically tested over a five-year period using agar gel immunodiffusion test (AGIDT) as part of a voluntary Bovine Leukemia Virus (BLV) control program. After five years of removing infected animals from the herds based on BLV-AGIDT serological status, blood samples from 332 cattle in these farms were collected and analyzed side by side by AGIDT and enzyme-linked immunosorbent assay (ELISA) to detect antibodies against BLV. AGIDT detected 29.2% (97) and 16.0% (53) of the animals as positive and weak positive respectively, whereas ELISA detected 58.2% (193) cattle as positive. The prevalence of BLV-antibodies determined with AGIDT in the dairy farms oscillated between 0% and 86%, whereas prevalence determined by ELISA ranged between 28% and 100% in the same farms. Although both techniques showed similarly results in farms with high BLV-prevalence, ELISA detected a larger proportion of BLV-positive, especially in farms with low or no BLV-prevalence based on AGIDT, leading to wrong assumptions in terms of farm level control efforts. Our results strongly suggest that AGIDT alone is inadequate to implement BLV control programs and ELISA is a more adequate test for BLV surveillance and control programs. 展开更多
关键词 BLV SEROLOGICAL Testing control programS
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Improving tuberculosis case detection in underdeveloped multi-ethnic regions with high disease burden:a case study of integrated control program in China 被引量:4
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作者 Jun Li Xiao-Qiu Liu +8 位作者 Shi-Wen Jiang Xue Li Fei Yu Yan Wang Yong Peng Xiao-Ming Gu Yan-Ni Sun Hui Zhang Li-Xia Wang 《Infectious Diseases of Poverty》 SCIE 2017年第1期1343-1351,共9页
Background:In the underdeveloped multi-ethnic regions of China,high tuberculosis(TB)burden and regional inequity in access to healthcare service increase the challenge of achieving the End TB goals.Among all the provi... Background:In the underdeveloped multi-ethnic regions of China,high tuberculosis(TB)burden and regional inequity in access to healthcare service increase the challenge of achieving the End TB goals.Among all the provinces,the highest TB burden is reported in Xinjiang,where ethnic minorities and older people have suffered most.However,current case-finding strategy is inadequate given the complex social determinants and suboptimal case detection rates.Thus,we developed an integrated TB control program to improve case detection and conducted a pilot in Xinjiang from 2014 to 2015.In this case study,we summarized the activities and key findings.We also shared the experiences and challenges of implementing interventions and provided recommendations to inform the TB control program in the future.Case presentation:The pilot interventions were implemented in one selected town in Yining based on local TB control programs.By applying tailor-made educational materials,outreach TB educational activities were conducted in diverse ways.In 22 Masjids,the trained imams promoted TB education to the Muslims,covering 20,440 persontimes in 88 delivered preaching sessions.In seven schools,1944 students were educated by the teachers and contributed to educating 6929 family members.In the village communities,13,073 residents participated in household education and screening.Among them,12,292 people aged under 65 years were investigated for suspicious pulmonary TB symptoms,where six TB patients were diagnosed out of 89 TB suspects;781 older people were mobilized for screening directly by chest X-ray,where 10 patients were diagnosed out of 692 participants.Supportive healthcare system,multi-sectoral cooperation and multi-channel financing mechanism were the successful experiences of implementation.The interventions were proved to be more effective than the previous performance:the number of TB suspects consulting doctors and patients detected increased by 50%and 26%,respectively.The potential challenges,implications and recommendations should been taken into account for further program improvement.Conclusions:In underdeveloped multi-ethnic regions with high TB burden,improving case detection is necessary and the interventions can be feasible and effective within a supportive system.More intensive educational and training approaches,a high index of TB suspicion and prioritization of older people in screening are recommended.To sustain and scale up the program,the impacts,cost-effectiveness,feasibility and acceptability of interventions warrant further research and evaluation in each specific context. 展开更多
关键词 TUBERCULOSIS TB control program Outreach education Household screening Case study/pilot Ethnic groups Aged/older people Xinjiang/China
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Soil organic carbon dynamics in Xilingol grassland of northern China induced by the Beijing-Tianjin Sand Source Control Program 被引量:2
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作者 Liangxia ZHANG Wei CAO Jiangwen FAN 《Frontiers of Earth Science》 SCIE CAS CSCD 2017年第2期407-415,共9页
To mitigate impacts of sandstorms on northern China, the Chinese government launched the Beijing- Tianjin Sand Source Control Program (BTSSCP) in 2000. The associated practices (i.e., cultivation, enclosure, and ae... To mitigate impacts of sandstorms on northern China, the Chinese government launched the Beijing- Tianjin Sand Source Control Program (BTSSCP) in 2000. The associated practices (i.e., cultivation, enclosure, and aerial seeding) were expected to greatly enhance grassland carbon sequestration. However, the BTSSCP-induced soil organic carbon (SOC) dynamics remain elusive at a regional level. Using the Xilingol League in Inner Mongolia for a case study, we examined the impacts from 2000 to 2006 of the BTSSCP on SOC stocks using the IPCC carbon budget inventory method. Results indicated that over all practices SOC storage increased by 1.7%, but there were large differences between practices. SOC increased most rapidly at the rate of 0.3 Mg C.ha-1 "yr-1 under cultivation, but decreased signifi- cantly under aerial seeding with moderate or heavy grazing (0.3 vs.0.6 Mg C-ha-I .yr-1). SOC increases varied slightly for grassland types, ranging from 0.10 Mg C-ha-1 .yr-a for temperate desert steppe to 0.16 Mg C.ha-l.yr-1 for temperate meadow steppe and lowland meadow. The overall economic benefits of the SOC sink were estimated to be 4.0 million CNY. Aerial seeding with no grazing was found to be the most cost-effective practice. Finally, we indicated that at least 55.5 years (shortest for cultivation) were needed for the grasslands to reach their potential carbon stocks. Our findings highlight the importance and effectiveness of BTSSCP in promoting terrestrial carbon sequestration which may help mitigate climate change, and further stress the need for more attention to the effective- ness of specific practices. 展开更多
关键词 grassland carbon sequestration ecologicalrestoration Beijing-Tianjin Sand Source control program(BTSSCP) IPCC carbon budget inventory method
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Program structures and synchronization schemes in numerical coordinate controllers of three-wire welding 被引量:2
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作者 刘超英 黄石生 《China Welding》 EI CAS 2006年第4期9-12,共4页
In the three-wire welding system, a welding process consists of the operations of four devices, namely three welding machines and one bogie. The operations need to be synchronized by a numerical coordinate controller ... In the three-wire welding system, a welding process consists of the operations of four devices, namely three welding machines and one bogie. The operations need to be synchronized by a numerical coordinate controller ( NCC ). In this paper, we will discuss a tnsk-job-procedure cubic program structure. Under this structure, the devices are synchronized and isolated at the same time. This cubic program structure can also be used as a reference for other multi-device or multi-unit manufacturing processes. 展开更多
关键词 three-wire welding coordinate control program structrure ISOLATION
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Approximate Dynamic Programming for Self-Learning Control 被引量:14
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作者 DerongLiu 《自动化学报》 EI CSCD 北大核心 2005年第1期13-18,共6页
This paper introduces a self-learning control approach based on approximate dynamic programming. Dynamic programming was introduced by Bellman in the 1950's for solving optimal control problems of nonlinear dynami... This paper introduces a self-learning control approach based on approximate dynamic programming. Dynamic programming was introduced by Bellman in the 1950's for solving optimal control problems of nonlinear dynamical systems. Due to its high computational complexity, the applications of dynamic programming have been limited to simple and small problems. The key step in finding approximate solutions to dynamic programming is to estimate the performance index in dynamic programming. The optimal control signal can then be determined by minimizing (or maximizing) the performance index. Artificial neural networks are very efficient tools in representing the performance index in dynamic programming. This paper assumes the use of neural networks for estimating the performance index in dynamic programming and for generating optimal control signals, thus to achieve optimal control through self-learning. 展开更多
关键词 近似动态程序 自学习控制 神经网络 人工智能
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Stability of Nonlinear Systems Using Optimal Fuzzy Controllers and Its Simulation by Java Programming 被引量:1
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作者 Mohammad Javad Mahmoodabadi Saideh Arabani Mostaghim 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1519-1527,共9页
In this paper, at first, the single input rule modules(SIRMs) dynamically connected fuzzy inference model is used to stabilize a double inverted pendulum system. Then, a multiobjective particle swarm optimization(MOPS... In this paper, at first, the single input rule modules(SIRMs) dynamically connected fuzzy inference model is used to stabilize a double inverted pendulum system. Then, a multiobjective particle swarm optimization(MOPSO) is implemented to optimize the fuzzy controller parameters in order to decrease the distance error of the cart and summation of the angle errors of the pendulums, simultaneously. The feasibility and efficiency of the proposed Pareto front is assessed in comparison with results reported in literature and obtained from other algorithms.Finally, the Java programming with applets is utilized to simulate the stability of the nonlinear system and explain the internetbased control. 展开更多
关键词 Double INVERTED PENDULUM system fuzzy control Java programMING MULTI-OBJECTIVE algorithm particle SWARM optimization(PSO)
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Using Automation Controller System and Simulation Program for Testing Closed Circuits of Mini-Sprinkler Irrigation System 被引量:2
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作者 Hani A. Mansour Hany M. Mehanna +1 位作者 Mohamed E. El-Hagarey Ahmehd S. Hassan 《Open Journal of Modelling and Simulation》 2013年第2期14-23,共10页
The field experiments were conducted at the experimental farm of Faculty of agricultural, southern Illinois University SIUC, USA. The project makes the irrigation automated. With the use of low cost sensors and the si... The field experiments were conducted at the experimental farm of Faculty of agricultural, southern Illinois University SIUC, USA. The project makes the irrigation automated. With the use of low cost sensors and the simple circuitry makes currently project a low cost product, which can be bought even by a poor farmer. This research work is best suited for places where water is scares and has to be used in limited quantity and this proposal is a model to modernize the agriculture industries at a mass scale with optimum expenditure. In the field of agricultural engineering, use of sensor method of irrigation operation is important and it is well known that closed circuits of Mini-sprinkler irrigation system are very economical and efficient. Closed circuits are considered one of the modifications of Mini-sprinkler irrigation system, and added advantages to Mini-sprinkler irrigation system because it can relieve low operating pressures problem at the end of the lateral lines. In the conventional closed circuits of Mini-sprinkler irrigation system, the farmer has to keep watch on irrigation timetable, which is different for different crops. Using this system, one can save manpower, water to improve production and ultimately profit. The data could be summarized in following: Irrigation methods under study when using lateral length 60 mcould be ranked in the following ascending order according the values of the predicted and measured head losses CM1M-SIS CM2M-SIS.The correlation (Corr.) coefficients were used to compare the predicted and measured head losses along the lateral lines of all the closed circuits designs. Generally, the values of correlation analysis were (>0.90) were obtained with 0% field slope60 mlength (experimental conditions) for all closed circuits.The interaction between irrigation methods: at the start there are significant differences between CM2M-SIS and CM1M-SIS. 展开更多
关键词 Automation controller Simulation program Mini-Sprinkler IRRIGATION LATERAL CLOSED CIRCUITS
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Linear Programming for Optimum PID Controller Tuning 被引量:1
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作者 Edimar J. Oliveira Leonardo M. Honorio +1 位作者 Alexandre H. Anzai Tamara X. Soares 《Applied Mathematics》 2014年第6期886-897,共12页
This work presents a new methodology based on Linear Programming (LP) to tune Proportional-Integral-Derivative (PID) control parameters. From a specification of a desired output time domain of the plant, a linear opti... This work presents a new methodology based on Linear Programming (LP) to tune Proportional-Integral-Derivative (PID) control parameters. From a specification of a desired output time domain of the plant, a linear optimization system is proposed to adjust the PID controller leading the output signal to stable operation condition with minimum oscillations. The constraint set used in the optimization process is defined by using numerical integration approach. The generated optimization problem is convex and easily solved using an interior point algorithm. Results obtained using familiar plants from literature have shown that the proposed linear programming problem is very effective for tuning PID controllers. 展开更多
关键词 LINEAR programMING Optimal control INTERIOR POINT Method PID Tuning
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Optimal Control for a Class of Complex Singular System Based on Adaptive Dynamic Programming 被引量:6
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作者 Zhan Shi Zhanshan Wang 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第1期188-197,共10页
This paper presents a new design approach to achieve decentralized optimal control of high-dimension complex singular systems with dynamic uncertainties. Based on robust adaptive dynamic programming(robust ADP) method... This paper presents a new design approach to achieve decentralized optimal control of high-dimension complex singular systems with dynamic uncertainties. Based on robust adaptive dynamic programming(robust ADP) method, controllers for solving the singular systems optimal control problem are designed. The proposed algorithm can work well when the system model is not exactly known but the input and output data can be measured. The policy iteration of each controller only uses their own states and input information for learning,and do not need to know the whole system dynamics. Simulation results on the New England 10-machine 39-bus test system show the effectiveness of the designed controller. 展开更多
关键词 Adaptive dynamic programMING (ADP) DECENTRALIZED control frequency control power system SINGULAR systems
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CONTROLLING ROBOT MANIPULATORS BY DYNAMIC PROGRAMMING 被引量:1
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作者 MarcJ.Richard 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1995年第1期20-33,共14页
A certain number of considerations should be taken into account in the dynamic control of robot manipulators as highly complex non-linear systems.In this article,we provide a detailed presentation of the mechanical an... A certain number of considerations should be taken into account in the dynamic control of robot manipulators as highly complex non-linear systems.In this article,we provide a detailed presentation of the mechanical and electrical impli- cations of robots equipped with DC motor actuators.This model takes into account all non-linear aspects of the system.Then,we develop computational algorithms for optimal control based on dynamic programming.The robot's trajectory must be predefined,but performance criteria and constraints applying to the system are not limited and we may adapt them freely to the robot and the task being studied.As an example,a manipulator arm with 3 degrees of freedom is analyzed. 展开更多
关键词 dynamic programming robot manipulators optimal control dynamic modelling method
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An Optimal Control Scheme for a Class of Discrete-time Nonlinear Systems with Time Delays Using Adaptive Dynamic Programming 被引量:17
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作者 WEI Qing-Lai ZHANG Hua-Guang +1 位作者 LIU De-Rong ZHAO Yan 《自动化学报》 EI CSCD 北大核心 2010年第1期121-129,共9页
关键词 非线性系统 最优控制 控制变量 动态规划
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Control strategy optimization using dynamic programming method for synergic electric system on hybrid electric vehicle
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作者 Yuan-Bin Yu Qing-Nian Wang +2 位作者 Hai-Tao Min Peng-Yu Wang Chun-Guang Hao 《Natural Science》 2009年第3期222-228,共7页
Dynamic Programming (DP) algorithm is used to find the optimal trajectories under Beijing cycle for the power management of synergic electric system (SES) which is composed of battery and super capacitor. Feasible rul... Dynamic Programming (DP) algorithm is used to find the optimal trajectories under Beijing cycle for the power management of synergic electric system (SES) which is composed of battery and super capacitor. Feasible rules are derived from analyzing the optimal trajectories, and it has the highest contribution to Hybrid Electric Vehicle (HEV). The methods of how to get the best performance is also educed. Using the new Rule-based power management strat-egy adopted from the optimal results, it is easy to demonstrate the effectiveness of the new strategy in further improvement of the fuel economy by the synergic hybrid system. 展开更多
关键词 DYNAMIC programMING control STRATEGY Optimization Synergic ELECTRIC System HEV
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《全国结核病防治规划(2024—2030年)》解读 被引量:5
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作者 陈伟 李雪 +4 位作者 刘小秋 李玉红 倪妮 张慧 赵雁林 《中国防痨杂志》 北大核心 2025年第2期130-136,共7页
为全面加强结核病防治工作,国家疾病预防控制局等9部委联合制定下发了《全国结核病防治规划(2024—2030年)》。笔者从规划制定的背景、目标和工作指标、防治措施、保障措施等方面对规划的相关内容进行详细解释和说明,以期对规划目标和... 为全面加强结核病防治工作,国家疾病预防控制局等9部委联合制定下发了《全国结核病防治规划(2024—2030年)》。笔者从规划制定的背景、目标和工作指标、防治措施、保障措施等方面对规划的相关内容进行详细解释和说明,以期对规划目标和工作指标要求,以及主要防治措施的工作内容等达成共识,为推动制定本地区结核病防治规划,以及促进规划落实提供支撑。 展开更多
关键词 结核 综合预防 传染病控制 国家卫生规划 卫生措施
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An Enhanced Genetic Programming Algorithm for Optimal Controller Design
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作者 Rami A. Maher Mohamed J. Mohamed 《Intelligent Control and Automation》 2013年第1期94-101,共8页
This paper proposes a Genetic Programming based algorithm that can be used to design optimal controllers. The proposed algorithm will be named a Multiple Basis Function Genetic Programming (MBFGP). Herein, the main id... This paper proposes a Genetic Programming based algorithm that can be used to design optimal controllers. The proposed algorithm will be named a Multiple Basis Function Genetic Programming (MBFGP). Herein, the main ideas concerning the initial population, the tree structure, genetic operations, and other proposed non-genetic operations are discussed in details. An optimization algorithm called numeric constant mutation is embedded to strengthen the search for the optimal solutions. The results of solving the optimal control for linear as well as nonlinear systems show the feasibility and effectiveness of the proposed MBFGP as compared to the optimal solutions which are based on numerical methods. Furthermore, this algorithm enriches the set of suboptimal state feedback controllers to include controllers that have product time-state terms. 展开更多
关键词 GENETIC programMING OPTIMAL control Nonlinear control System
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基于PLC控制的毛纺织品自动分拣线控制系统设计 被引量:2
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作者 顾玉娥 万一凡 《毛纺科技》 北大核心 2025年第2期104-109,共6页
为提升毛纺织品的分拣质量与效率,设计基于PLC控制的毛纺织品自动分拣线控制系统。依据毛纺织品分拣需求,划分4个自动分拣线控制区域,搭建毛纺织品自动分拣线架构;选取S7-1500PLC控制器,结合PLC控制器配置情况,设计PLC控制器接线及PLC... 为提升毛纺织品的分拣质量与效率,设计基于PLC控制的毛纺织品自动分拣线控制系统。依据毛纺织品分拣需求,划分4个自动分拣线控制区域,搭建毛纺织品自动分拣线架构;选取S7-1500PLC控制器,结合PLC控制器配置情况,设计PLC控制器接线及PLC控制信号表;引入修正因子,控制输送线的运行速度,制定自动分拣线计数程序,实现毛纺织品自动分拣线的设计与运行。实验数据显示:在不同实验工况背景下,应用自动分拣线后获得的毛纺织品分拣效率最大值为920 kg/h,毛纺织品分拣准确率最大值为94%,所设计的自动分拣线应用效果较好。 展开更多
关键词 PLC 控制区域划分 毛纺织品 多道控制 自动分拣线 控制程序
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Implementation of Dynamic Matrix Control on Field Programmable Gate Array
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作者 兰建 李德伟 +1 位作者 杨楠 席裕庚 《Journal of Shanghai Jiaotong university(Science)》 EI 2011年第4期441-446,共6页
High performance computer is often required by model predictive control(MPC) systems due to the heavy online computation burden.To extend MPC to more application cases with low-cost computation facilities, the impleme... High performance computer is often required by model predictive control(MPC) systems due to the heavy online computation burden.To extend MPC to more application cases with low-cost computation facilities, the implementation of MPC controller on field programmable gate array(FPGA) system is studied.For the dynamic matrix control(DMC) algorithm,the main design idea and the implemental strategy of DMC controller are introduced based on a FPGA’s embedded system.The performance tests show that both the computation efficiency and the accuracy of the proposed controller can be satisfied due to the parallel computing capability of FPGA. 展开更多
关键词 model predictive control(MPC) dynamic matrix control(DMC) quadratic programming(QP) active set programmable logic device field programmable gate array(FPGA)
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Call for papers Journal of Control Theory and Applications Special issue on Approximate dynamic programming and reinforcement learning
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《控制理论与应用(英文版)》 EI 2010年第2期257-257,共1页
Approximate dynamic programming (ADP) is a general and effective approach for solving optimal control and estimation problems by adapting to uncertain and nonconvex environments over time.
关键词 Call for papers Journal of control Theory and Applications Special issue on Approximate dynamic programming and reinforcement learning
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