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Precision Point to Point Control of Proportional Valve Controlled Motor with a Time Varying Load
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作者 彭熙伟 王渝 王向周 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期288-293,共6页
Aim In accordance with the positioning control for valve controlled motor electrohydraulic proportional servo systems driving the static load torque, the positioning performance was studied in the presence of the ti... Aim In accordance with the positioning control for valve controlled motor electrohydraulic proportional servo systems driving the static load torque, the positioning performance was studied in the presence of the time? varying deadzone and gain. Methods The large positioning errors caused by the time varying deadzone were significantly reduced by using the dynamic compensation method for the deadzone; and the large overshoot caused by the time varying gain were dramatically reduced by using the three section intelligent control schemes. Results Experimental results demonstrated that the positioning performance of rapid response, high accuracy and smaller or even no overshoot was achieved under a wide variations of load torque. Conclusion The good positioning performance for valve controlled motor servo systems has been achieved in the presence of the time varying deadzone and gain. 展开更多
关键词 fuzzy control intelligent control deadzone compensation point to point control electrohydraulic proportional servo system
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NN adaptive pole placement method for sintering finish point control 被引量:1
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作者 LiPeng QingLi +1 位作者 WenLi ShufenLi 《Journal of University of Science and Technology Beijing》 CSCD 2004年第5期477-479,共3页
A neural network model with a special structure, which is divided into linearand nonlinear parts, was proposed for identification of a nonlinear system. In this model, thenonlinear part of the object is treated as a m... A neural network model with a special structure, which is divided into linearand nonlinear parts, was proposed for identification of a nonlinear system. In this model, thenonlinear part of the object is treated as a measured disturbance, and is compensated by a feedforward method; an adaptive pole placement algorithm is used to control the linear part of theobject. The simulation results show that the identification efficiency and accuracy are improvedwhen the new controller is applied to sintering finish point control. 展开更多
关键词 nonlinear system neural network identifier adaptive pole placementcontroller sintering finish point control
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CONSTANT WORK-POINT CONTROL FOR PARALLEL HYBRID SYSTEM WITH CAPACITOR ACCUMULATOR IN HYDRAULIC EXCAVATOR 被引量:4
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作者 ZHANG Yanting WANG Qingfeng XIAO Qing FU Qiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期505-508,共4页
Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hyb... Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hybrid construction machinery is established, and experimental study on constant work-point control for parallel hybrid system with capacitor accumulator is carried out using the pressure and flow rate derived from boom cylinder of hydraulic excavator in actual work as the simulating loads. A program of double work-point control is proposed and proved by further experiments. 展开更多
关键词 Hybrid Hydraulic excavator Capacitor accumulator Constant work-point control Double work-point control
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Strike Point Control on EAST Using an Isoflux Control Method
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作者 邢哲 肖炳甲 +2 位作者 罗正平 M.L.WALKER D.A.HUMPHREYS 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第9期774-780,共7页
For the advanced tokamak,the particle deposition and thermal load on the divertor is a big challenge.By moving the strike points on divertor target plates,the position of particle deposition and thermal load can be sh... For the advanced tokamak,the particle deposition and thermal load on the divertor is a big challenge.By moving the strike points on divertor target plates,the position of particle deposition and thermal load can be shifted.We could adjust the Poloidal Field(PF) coil current to achieve the strike point position feedback control.Using isoflux control method,the strike point position can be controlled by controlling the X point position.On the basis of experimental data,we establish relational expressions between X point position and strike point position.Benchmark experiments are carried out to validate the correctness and robustness of the control methods.The strike point position is successfully controlled following our command in the EAST operation. 展开更多
关键词 EAST plasma control system strike point control
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Construction Project Management and Construction Quality Control Strategy
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作者 Qinrong Zhang 《Journal of Architectural Research and Development》 2024年第4期45-50,共6页
With the gradual acceleration of the urbanization process,the construction industry has been developing rapidly.As the key link to ensure the quality and safety of the project,construction management and construction ... With the gradual acceleration of the urbanization process,the construction industry has been developing rapidly.As the key link to ensure the quality and safety of the project,construction management and construction quality control are of great significance to enhance the competitiveness of construction enterprises and realize sustainable development.In this paper,the effective strategy of construction management and the effective strategy of construction quality control will be discussed in depth,aiming at providing useful management and quality control strategies for construction enterprises. 展开更多
关键词 Construction engineering management Construction quality control STRATEGY Quality control point
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NUMERICAL SIMULATION OF MOLTEN POOL AND CONTROL STRATEGY OF KISS POINT IN A TWIN-ROLL STRIP CASTING PROCESS 被引量:2
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作者 G.M. Cao C.G. Li Z. Y. Liu D. Wu G.D. Wang X.H. Liu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第6期459-468,共10页
Coupled turbulent flow, temperature fields of the twin-roll casting strip process were simulated by three-dimensional finite element method. Based on the heat balance calculation and using inverse methods between the ... Coupled turbulent flow, temperature fields of the twin-roll casting strip process were simulated by three-dimensional finite element method. Based on the heat balance calculation and using inverse methods between the simulations and real experiments, the relational models among casting speed, location, and coefficient of heat transfer between molten metal and rolls in different regions are given. In the simulation, the calculated surface temperatures are in good agreement with the measured values. An on-line model of kiss point is derived by simulations and the geometry of molten pool, corresponding control strategy is also proposed. 展开更多
关键词 Twin-roll strip casting Coupled temperature and flow field Numerical simulation Kiss point control strategy
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The Roles of Countrywomen in Controlling Non-point Source Pollution 被引量:4
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作者 Jiang Dongmei Zhou Yuanfang Lu Genfa 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第2期28-32,共5页
The main causes of non-point source pollution in Taihu Lake are the improper ways of crop production, animal husbandry, and daily runoff. The paper discusses the relationship between countrywomen and non-point source ... The main causes of non-point source pollution in Taihu Lake are the improper ways of crop production, animal husbandry, and daily runoff. The paper discusses the relationship between countrywomen and non-point source pollution control by 731 questionnaires in Weidu village and 466 questionnaires in Dapu Town. The roles of countrywomen have changed in families and they have close relationship with non-point source pollution. Furthermore, we discuss the possibility and methods of organizing countrywomen in non-point source pollution control. 展开更多
关键词 countrywomen non-point source pollution control ROLE
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Study on the Control Model of Rural Non-point Source Pollution——Taking Ninghe County in Tianjin as an Example 被引量:7
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作者 YANG Yong CHEN Ying +4 位作者 ZHANG Xiao-lan SONG Bing-kui WANG Wen-mei ZHAO Lei ZHANG Yuan 《Meteorological and Environmental Research》 CAS 2011年第6期85-89,92,共6页
[Objective] The aim was to study the control model of rural non-point source pollution.[Method] Taking Ninghe County(a typical agricultural county in Tianjin) as an example,the current development of local economy and... [Objective] The aim was to study the control model of rural non-point source pollution.[Method] Taking Ninghe County(a typical agricultural county in Tianjin) as an example,the current development of local economy and society and characteristics of rural non-point source pollution were studied firstly,then the control model of rural non-point source pollution suitable for Ninghe County was constructed,and its environmental and economic benefits were analyzed finally.[Result] According to the sources of non-point source pollution,the control model of rural non-point source pollution in Ninghe County was divided into three modules from the aspects of planting industry,livestock raising industry and rural living.The main content of non-point source pollution control module of planting industry was composed of rational utilization of chemicals,water-saving irrigation,diversified utilization of straw etc.Non-point source pollution control module of livestock raising industry focused on the site selection of farm or raising zones,choice of raising mode,comprehensive utilization of livestock waste etc.In the non-point source pollution control module of rural living,villages were divided into two types(small town and ecological village) based on various geographical positions.In a word,these three modules were interrelated and targeted for non-point source pollution control in villages under different development situations.[Conclusion] The study could provide references for the rural non-point source pollution control in Hai River basin and other regions of Northern China. 展开更多
关键词 Rural area Non-point source pollution control model China
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法国阿尔斯通公司的Point-on-Wave Controller 被引量:8
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作者 程战斌 《西北电力技术》 2004年第6期42-45,共4页
本文介绍了大唐韩城第二发电有限责任公司工期2×600 MW工程中采用的国内首次引进法国阿尔斯通公司生产的断路器控制器RPH2的工作原理。以及在不同工况下,如何通过控制断路器各相的分/合闸时间点,来减少断路器正常分/合闸对设备和... 本文介绍了大唐韩城第二发电有限责任公司工期2×600 MW工程中采用的国内首次引进法国阿尔斯通公司生产的断路器控制器RPH2的工作原理。以及在不同工况下,如何通过控制断路器各相的分/合闸时间点,来减少断路器正常分/合闸对设备和系统造成冲击。最后介绍了该装置的环境补偿、自适应和负荷电流测量功能。 展开更多
关键词 断路器 分合闸时间点 控制装置 励磁涌流 操作过电压
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Analysis of Microbial Contamination Factors and Critical Control Points in the Process of Hog Slaughter and Production
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作者 Liu Xiuping Tang Yushun +2 位作者 Liu Yonghua Kou Xu Tang Feng 《Animal Husbandry and Feed Science》 CAS 2015年第4期200-202,共3页
In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected, and critical control poin... In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected, and critical control points in the progress of hog slaughter and processing were analyzed. The results showed that microbial con- taminatian existed in the entire slaughter and processing progress, including shower and assassination bloodletting, separation of the internal organs, chopping boards, workshop environment, personal hygiene of the operators, etc. , which should be paid more attention to. The results indicated that reasonable protection measures should be carried out, disinfection awareness of the operators should be improved, and regular disinfection should be ruled under the condition of continu- ous operation. 展开更多
关键词 Microbial contamination Critical control points Hog slaughter
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Variable Parameter Nonlinear Control for Maximum Power Point Tracking Considering Mitigation of Drive-train Load 被引量:2
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作者 Zaiyu Chen Minghui Yin +3 位作者 Lianjun Zhou Yaping Xia Jiankun Liu Yun Zou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第2期252-259,共8页
Since mechanical loads exert a significant influence on the life span of wind turbines, the reduction of transient load on drive-train shaft has received more attention when implementing a maximum power point tracking... Since mechanical loads exert a significant influence on the life span of wind turbines, the reduction of transient load on drive-train shaft has received more attention when implementing a maximum power point tracking U+0028 MPPT U+0029 controller. Moreover, a trade-off between the efficiency of wind energy extraction and the load level of drive-train shaft becomes a key issue. However, for the existing control strategies based on nonlinear model of wind turbines, the MPPT efficiencies are improved at the cost of the intensive fluctuation of generator torque and significant increase of transient load on drive train shaft. Hence, in this paper, a nonlinear controller with variable parameter is proposed for improving MPPT efficiency and mitigating transient load on drive-train simultaneously. Then, simulations on FAST U+0028 Fatigue, Aerodynamics, Structures, and Turbulence U+0029 code and experiments on the wind turbine simulator U+0028 WTS U+0029 based test bench are presented to verify the efficiency improvement of the proposed control strategy with less cost of drive-train load. © 2017 Chinese Association of Automation. 展开更多
关键词 AERODYNAMICS controllers Economic and social effects Maximum power point trackers Wind power Wind turbines
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The Research on the Methods to Confirm the Key Control Points of the Internal Accounting Control
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作者 Liuping Chen Sundi Zhao +1 位作者 Wenchen Zhao Jingjing Cao 《Journal of Modern Accounting and Auditing》 2005年第7期50-57,共8页
The control points are the key issue of the internal control, and the key control points mean the control joints that play an important part in the process of the operation. If these key control points are not well co... The control points are the key issue of the internal control, and the key control points mean the control joints that play an important part in the process of the operation. If these key control points are not well controlled, the process of the operation disposal will be mistaken and cannot reach the goal. However, for the confirmation of the control points, many studies only do qualitative research from the important aspect instead of quantificational research. They are devoid of a series of scientific methods. This paper advances quantificational methods to confirm the key control points from two aspects of job evaluation and mathematics model. 展开更多
关键词 accounting control key control points quantificational methods
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New Normal Control of Agricultural Non-point Source Pollution in the Dianchi Lake Basin 被引量:9
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作者 Xia Tiyuan Chen Zebin Jin Song 《Meteorological and Environmental Research》 CAS 2017年第2期63-72,共10页
Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,previous and current situation of agricultural production and a... Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,previous and current situation of agricultural production and agricultural non-point source pollution control in the Dianchi Lake basin were studied,and countermeasures and suggestions of comprehensive control of agricultural non-point source pollution in the basin were proposed. 展开更多
关键词 The Dianchi LAKE BASIN AGRICULTURAL non-point source POLLUTION NEW NORMAL control Measures China
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Bezier Control Points Method to Solve Scheduling of Injections of Immunotherapeutic Agents
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作者 Fateme Ghomanjani 《Intelligent Control and Automation》 2012年第1期20-25,共6页
Cancer immunotherapy aims at enhancing immune system to defend against the tumor. However, it is associated with injecting small doses of tumor-bearing molecules or even using drugs. The problem is that how to schedul... Cancer immunotherapy aims at enhancing immune system to defend against the tumor. However, it is associated with injecting small doses of tumor-bearing molecules or even using drugs. The problem is that how to schedule these injections effectively and/or how to apply drugs in a way to decrease toxic side effects of drugs such that the tumor growth to be stopped or at least to be limited. Here, the theory of optimal control has been applied to find the optimal schedule of injections of an immunotherapeutic agent against cancer. The numerical method employed works for any dynamic linear system and has almost precise solution. In this work, it was tested for a well known model of the tumor immune system interaction. 展开更多
关键词 IMMUNOTHERAPY BEZIER control points Constrained Optimal control
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Maximizing the Absorbed Power of A Point Absorber Using An FA-Based Optimized Model Predictive Control
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作者 Negar RAHIMI Reihaneh Kardehi MOGHADDAM 《China Ocean Engineering》 SCIE EI CSCD 2018年第6期696-705,共10页
This paper presents an extended model predictive controller for maximizing the absorbed power of a point absorber wave energy converter. Owing to the great influence of controller parameters upon the absorbed power, t... This paper presents an extended model predictive controller for maximizing the absorbed power of a point absorber wave energy converter. Owing to the great influence of controller parameters upon the absorbed power, the optimization of these parameters is carried out for the first time by a firefly algorithm(FA). Error, the difference between output velocity of buoy and input wave speed which leads to power maximization in the optimized MPC is compared with the classical MPC. Simulation results indicate that given the high accuracy and acceptable speed of the algorithm, it can adjust the parameters of the controller to the point where system error decreased effectively and the absorbed energy increased about 4 MW. 展开更多
关键词 wave energy point absorber predictive controller firefly algorithm
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Advances in History, Current Situation and Control of Agricultural Non-point Source Pollution in the Dianchi Lake Basin
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作者 Xia Tiyuan Chen Zebin Jin Song 《Meteorological and Environmental Research》 CAS 2017年第1期52-58,60,共8页
Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,advances in the history,current situation and control measures ... Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,advances in the history,current situation and control measures of agricultural non-point source pollution in the basin were summarized to provide theoretical and technical support for the thorough improvement of present situation of water pollution in the basin. 展开更多
关键词 The Dianchi LAKE BASIN AGRICULTURAL non-point source POLLUTION control Measures China
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Controlled-release fertilizer(CRF): A green fertilizer for controlling non-point contamination in agriculture 被引量:20
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作者 MAOXiao-yun SUNKe-jun WANGDe-han LIAOZong-wen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期181-184,共4页
Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has... Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs, the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture. 展开更多
关键词 controlled-release fertilizer N use efficiency non-point contamination
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AUTOMATIC SEARCHING OF CONTROL POINT IN NOAA AVHRR IMAGE
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作者 Shu Ning Shi Huaxiang 《Geo-Spatial Information Science》 1999年第1期26-29,67,共5页
This paper discusses the approaches for automatical searching of control points in the NOAA AVHRR image on the basis of data rearrangement in the form of latitude and longitude grid. The vegetation index transformatio... This paper discusses the approaches for automatical searching of control points in the NOAA AVHRR image on the basis of data rearrangement in the form of latitude and longitude grid. The vegetation index transformation and multi-level matching strategies have been proven effective and successful as the experiments show while the control point database is established. 展开更多
关键词 control point database automatical SEARCHING grid IMAGE VEGETATION index transformation MULTI-LEVEL matching NOAA AVHRR IMAGE
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Set-point Filter Design for a Two-degree-of-freedom Fractional Control System
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作者 Fabrizio Padula Antonio Visioli 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第4期451-462,共12页
This paper focuses on a new approach to design(possibly fractional) set-point filters for fractional control systems.After designing a smooth and monotonic desired output signal,the necessary command signal is obtaine... This paper focuses on a new approach to design(possibly fractional) set-point filters for fractional control systems.After designing a smooth and monotonic desired output signal,the necessary command signal is obtained via fractional input-output inversion.Then,a set-point filter is determined based on the synthesized command signal.The filter is computed by minimizing the 2-norm of the difference between the command signal and the filter step response.The proposed methodology allows the designer to synthesize both integer and fractional setpoint filters.The pros and cons of both solutions are discussed in details.This approach is suitable for the design of two degreeof-freedom controllers capable to make the set-point tracking performance almost independent from the feedback part of the controller.Simulation results show the effectiveness of the proposed methodology. 展开更多
关键词 Fractional control systems two-degree-of-freedom control set-point following system inversion
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The Bezier Control Points Method for Solving Delay Differential Equation
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作者 Fateme Ghomanjani Mohammad Hadi Farahi 《Intelligent Control and Automation》 2012年第2期188-196,共9页
In this paper, Bezier surface form is used to find the approximate solution of delay differential equations (DDE’s). By using a recurrence relation and the traditional least square minimization method, the best contr... In this paper, Bezier surface form is used to find the approximate solution of delay differential equations (DDE’s). By using a recurrence relation and the traditional least square minimization method, the best control points of residual function can be found where those control points determine the approximate solution of DDE. Some examples are given to show efficiency of the proposed method. 展开更多
关键词 BEZIER control pointS Delay Differential Equation RESIDUAL Function BOUNDARY Value Problem Proportional DELAYS
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