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Fault Estimation and Accommodation for Networked Control Systems with Transfer Delay 被引量:24
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作者 MAO Ze-Hui JIANG Bin 《自动化学报》 EI CSCD 北大核心 2007年第7期738-743,共6页
在这份报纸,差错评价和差错的一个方法为有转移延期和进程噪音的联网的控制系统(NCS ) 的容忍的控制被介绍。首先,联网的控制系统作为有转移的分离时间的系统推迟的 multiple-input-multiple-output (MIMO ) 被建模,处理噪音,并且... 在这份报纸,差错评价和差错的一个方法为有转移延期和进程噪音的联网的控制系统(NCS ) 的容忍的控制被介绍。首先,联网的控制系统作为有转移的分离时间的系统推迟的 multiple-input-multiple-output (MIMO ) 被建模,处理噪音,并且为无常建模。在这个模型下面并且在一些条件下面,一个差错评价方法被建议估计系统差错。根据差错评价和滑动模式控制理论的信息,一个差错容忍的控制器被设计恢复系统性能。最后,模拟结果被用来验证方法的效率。 展开更多
关键词 网络控制系统 迟滞转移 容错估计 容错控制 不确定性模型 滑动模型控制
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Repetitive PD control strategy with inverse transfer function compensation for CVCF inverter 被引量:2
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作者 ShanxuDUAN 《控制理论与应用(英文版)》 EI 2004年第2期121-125,共5页
A novel repetitive control strategy for the output waveform of single-phase CVCF inverters is presented. In this scheme, the inverse transfer function of inverter is used as a compensator to obtain stable and satisfy ... A novel repetitive control strategy for the output waveform of single-phase CVCF inverters is presented. In this scheme, the inverse transfer function of inverter is used as a compensator to obtain stable and satisfy harmonic rejection. Besides, PD controller is adopted to improve transient performance. Simulation and experimental results, which are gotten from a DSP-based 400Hz, 5.5KW inverter, indicate that the proposed control scheme can achieve not only low THD during steady-state operation but also fast transient response during load step change. 展开更多
关键词 INVERTER Inverse transfer function Repetitive control PD control
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Efficient oxidation of benzyl alcohol with heteropolytungstate as reaction-controlled phase-transfer catalyst 被引量:5
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作者 Zhi Huan Weng Jin Yan Wang Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第8期936-938,共3页
A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the pr... A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the properties of reaction-controlled phasetransfer catalysis, and they had excellent catalytic ability to the oxidation of benzyl alcohol. No other by-products were detected by gas chromatography. Once the hydrogen peroxide was consumed completely, the catalyst precipitated from solvent, and the results of the catalyst recycle showed that the catalyst had high stability. 展开更多
关键词 HETEROPOLYTUNGSTATE Reaction-controlled phase-transfer Benzyl alcohol BENZALDEHYDE Hydrogen peroxide
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A New Reaction-controlled Phase-transfer Catalyst System 被引量:1
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作者 MingQiangLI XiGaoJIAN GuiMeiWANG YanYU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第3期350-352,共3页
A new reaction-controlled phase-transfer catalyst system was designed and synthesized. In this system, heteropolytungstate [C7H7N(CH3)3]9PW9O34 was used for catalytic epoxidation of cyclohexene with H2O2 as the oxida... A new reaction-controlled phase-transfer catalyst system was designed and synthesized. In this system, heteropolytungstate [C7H7N(CH3)3]9PW9O34 was used for catalytic epoxidation of cyclohexene with H2O2 as the oxidant. The conversion of H2O2 was 100% and the yield of cyclohexene oxide was 87.1% based on cyclohexene. Infrared spectra showed that both fresh catalyst and the recovered catalyst do have completely same absorption peak, indicating the structure of catalyst is very stability and can be recycled. 展开更多
关键词 Reaction-controlled phase-transfer catalyst CYCLOHEXENE epoxidation.
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Local Government-owner Bidder and Corporate Control Transfer
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作者 Shufang Deng 《Journal of Modern Accounting and Auditing》 2006年第6期1-6,共6页
In this study, we discuss the financial constraints and the behavior of local governments. We expect that governments in relative wealthy region will act as a helping hand for companies trader its control on average, ... In this study, we discuss the financial constraints and the behavior of local governments. We expect that governments in relative wealthy region will act as a helping hand for companies trader its control on average, while those in relative poor region will be a grabbing hand. By dividing local governments into 3 categories according to its GDP per capita and Fiscal Revenue per capita, we test the relationship between government attributes and the long-term performance of listed companies in corporate control market. We find that target companies who are later controlled by the wealthiest government achieve better performance, while those who were later controlled by the poorest governments also achieve significant better long-term performance. 展开更多
关键词 local government ultimate ownership control transfer
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Mathematical model and magnetic-control mechanism of the stability of rotating spray transfer 被引量:14
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作者 殷树言 陈树君 +1 位作者 王军 徐鲁宁 《China Welding》 EI CAS 2003年第1期57-61,共5页
To realize stable rotating spray transfer in the region of high constant current is the key of realizing high deposition rate MAG welding process without helium in shielding gas and extending the welding current rang... To realize stable rotating spray transfer in the region of high constant current is the key of realizing high deposition rate MAG welding process without helium in shielding gas and extending the welding current range of traditional MAG welding process. In this paper, the magnetic control mechanism of the rotating spray transfer is stated and mathematical model is given. Theoretic basis is established, which implements high deposition rate MAG welding process with magnetic control instead of helium in shielding gas. 展开更多
关键词 magnetic control rotating spray transfer high deposition rates MAG welding process mathematical model
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GENERALIZED TRANSFER FUNCTION OF CONTROL SYSTEM AND AN IMPROVEMENT ON THE DECISION METHOD OF MOVEMENT STABILITY
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作者 叶寿桢 沙万乾 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第4期361-371,共11页
In this paper the definitions of generalized transfer functios of control system and itscontinuity are presented.Using generalized transfer function as a tool,a set of theorems fordeciding movement stability have been... In this paper the definitions of generalized transfer functios of control system and itscontinuity are presented.Using generalized transfer function as a tool,a set of theorems fordeciding movement stability have been constructed.Thus basing understanding of thecharacteristics of a control dynamics system on its measured procedure will simplify thedecision method of movement stability problems. 展开更多
关键词 link GENERALIZED transfer FUNCTION OF control SYSTEM AND AN IMPROVEMENT ON THE DECISION METHOD OF MOVEMENT STABILITY
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Transfer Function Model of Multirate Feedback Control Systems
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作者 肖建 唐磊 《Journal of Modern Transportation》 2001年第1期1-7,共7页
Based on the suitably defined multivariable version of Kranc operators and the extended input and output vectors, the multirate sampling plant is transformed to a equivalent time invariant single rate one, then the t... Based on the suitably defined multivariable version of Kranc operators and the extended input and output vectors, the multirate sampling plant is transformed to a equivalent time invariant single rate one, then the transfer function model of the multivariable multirate sampling plant is obtained. By combining this plant model with the time invariant description of the multirate controller in terms of extended vectors, the closed loop transfer function model of the multirate feedback control system can be determinated. This transfer function model has a very simple structure, and can be used as a basis for the analysis and synthesis of the multirate sampling feedback control systems in the frequency domain. 展开更多
关键词 feedback control transfer functions multirate digital control systems computer control
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Investigation on microprocessor based waveform control of short circuit transfer CO_2 welding 被引量:1
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作者 朱锦洪 石红信 +2 位作者 李兴霞 刘兆魁 涂益民 《China Welding》 EI CAS 2006年第4期26-29,共4页
A new kind of simple and flexible CO2 welding system was developed to carry out waveform control. The system consisted of IGBT inverter, PWM circuit and microprocessor unit ( MPU) , in which the output current of co... A new kind of simple and flexible CO2 welding system was developed to carry out waveform control. The system consisted of IGBT inverter, PWM circuit and microprocessor unit ( MPU) , in which the output current of constant current (CC) power supply could be changed according to transient physical state, and the variable down slope rate control could be used to ensure a stable welding process. The welding experiment results proved the effectiveness of this control approach. 展开更多
关键词 CO2 welding waveform control MICROPROCESSOR short circuit transfer
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Heteropolymolybdate as a New Reaction-controlled Phase-transfer Catalyst for Efficient Alcohol Oxidation with Hydrogen Peroxide
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作者 Zhi Huan WENG Jin Yan WANG Xi Gao JIAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期848-850,共3页
A new catalytic process for the synthesis of aldehyde from alcohol by oxidation with H202 with high selectivity, was studied. In this system, heteropolymolybdate [C7H7N(CH3)3]3 {PO4[MoO(O2)2]4} was utilized as the... A new catalytic process for the synthesis of aldehyde from alcohol by oxidation with H202 with high selectivity, was studied. In this system, heteropolymolybdate [C7H7N(CH3)3]3 {PO4[MoO(O2)2]4} was utilized as the reaction-controlled phase-transfer catalyst to catalyze oxidation of benzyl and aliphatic alcohols. The molar ratio of H2O2 and alcohol was 0.75, no other by-products were detected by gas chromatography, the results of oxidation reaction indicated that the catalyst has high activity and stability. 展开更多
关键词 Heteropolymolybdate reaction-controlled phase-transfer ALCOHOL oxidation.
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Simulation of droplet transfer process and current waveform control of CO_2 arc welding
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作者 俞建荣 吴立志 《中国有色金属学会会刊:英文版》 CSCD 2001年第5期667-670,共4页
A simulation system used in the arc welding short circuit transfer process and current waveform control process was developed in this paper. The simulation results are basically consistent with welding technical exper... A simulation system used in the arc welding short circuit transfer process and current waveform control process was developed in this paper. The simulation results are basically consistent with welding technical experiments. The simulation system can be used to simulate and test the current waveform control parameters with welding variables. By this simulation system, the influence regularities of the current waveform control parameters in the CO 2 arc welding droplet short circuit transfer process can be got. Moreover, the basic mode of real time current waveform control can be also established by the simulation testing. 展开更多
关键词 CO 2 arc welding droplet transfer current waveform control computer simulation
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Computer simulation of short-circuiting transfer welding under waveform control on inverter power source
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作者 杨立军 冯胜强 +3 位作者 董天顺School of Materials Science and Technology Hebei University of Technology Tianjin 李桓 《China Welding》 EI CAS 2007年第1期9-13,共5页
A simulation model is introduced about the non-linearity process of short-circuiting transfer in CO2 arc welding for displaying the interaction between the inverter power source and welding arc under waveform control.... A simulation model is introduced about the non-linearity process of short-circuiting transfer in CO2 arc welding for displaying the interaction between the inverter power source and welding arc under waveform control. In the simulation model, the feedback signals of current and voltage are taken respectively at the different phase in a short circuit periodic time and applied to the PWM (pulse width modulation) module in a model of inverter power source to control the output of power source. The simulation operation about the dynamic process of CO2 short-circuiting transfer welding is implemented on the founded simulation model with a peak arc current of 400 A and a peak voltage of 35 V, producing the dynamic arc waveforms which can embody the effect of inverter harmonic wave. The simulating waveforms are close to that of welding experiments. 展开更多
关键词 INVERTER SIMULATION short-circuiting transfer harmonic wave waveform control
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THE CONTROL OF POLYMETHACRYLATE MOLECULAR STRUCTURE BY GROUP TRANSFER POLYMERIZATION
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作者 OWEN W. WEBSTER 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1990年第1期1-9,共9页
INTRODUCTION Group transfer polymerization (GTP) is a method for controlling the structure of acrylic polymers in which reactive chain ends are covalentiy bound to a trimethylsilyl group. In the presence of a catalyst... INTRODUCTION Group transfer polymerization (GTP) is a method for controlling the structure of acrylic polymers in which reactive chain ends are covalentiy bound to a trimethylsilyl group. In the presence of a catalyst, monomer inserts into these chain ends between the silyl group and the last monomer unit. The process is illustrated by equation (1) for methyl methacrylate. GTP is a living polymerization, i. e., there is little or no chain termination and no chain transfer. A significant advantage of GTP is that it 展开更多
关键词 PMMA EA GTP rate PBMA THE control OF POLYMETHACRYLATE MOLECULAR STRUCTURE BY GROUP transfer POLYMERIZATION
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OBLIVIOUS TRANSFER WITH ACCESS CONTROL AND IDENTITY-BASED ENCRYPTION WITH ANONYMOUS KEY ISSUING
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作者 Xu Lingling Zhang Fangguo Wen Yamin 《Journal of Electronics(China)》 2011年第4期571-579,共9页
In ACM'CCS 2009,Camenisch,et al.proposed the Oblivious Transfer with Access Control(AC-OT) in which each item is associated with an attribute set and can only be available,on request,to the users who have all the ... In ACM'CCS 2009,Camenisch,et al.proposed the Oblivious Transfer with Access Control(AC-OT) in which each item is associated with an attribute set and can only be available,on request,to the users who have all the attributes in the associated set.Namely,AC-OT achieves access control policy for conjunction of attributes.Essentially,the functionality of AC-OT is equivalent to the sim-plified version that we call AC-OT-SV:for each item,one attribute is associated with it,and it is requested that only the users who possess the associated attribute can obtain the item by queries.On one hand,AC-OT-SV is a special case of AC-OT when there is just one associated attribute with each item.On the other hand,any AC-OT can be realized by an AC-OT-SV.In this paper,we first present a concrete AC-OT-SV protocol which is proved to be secure in the model defined by Camenisch,et al..Then from the protocol,interestingly,a concrete Identity-Based Encryption(IBE) with Anonymous Key Issuing(AKI) is given which is just a direct application to AC-OT-SV.By comparison,we show that the AKI protocol we present is more efficient in communications than that proposed by Chow. 展开更多
关键词 Oblivious transfer(OT) Access control(AC) Identity-Based Encryption(IBE) Anonymous Key Issuing(AKI)
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Design of control sequence of pulses for the population transfer of high dimensional spin 1/2 quantum systems
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作者 Cong Shuang Lou Yuesheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1226-1234,共9页
On the basis of the relationship between the Hamiltonian of spin 1/2 quantum system under control and the energy level structure and transitions, a radio frequency pulse sequence is designed using intuitive and half c... On the basis of the relationship between the Hamiltonian of spin 1/2 quantum system under control and the energy level structure and transitions, a radio frequency pulse sequence is designed using intuitive and half counter-intuitive sequences of pulse to transfer the population of the 3-qubit system coherently. The effectiveness of the designed control sequence is verified through the system simulation experiment of the evolution of state. In principle, the design method of the control pulse sequence proposed can be generalized to use in the quantum systems of higher dimension. 展开更多
关键词 quantum system control population transfer pulse sequence design intuitive sequence half counter-intuitive sequence
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Receiver Power Allocation and Transmitter Power Control Analysis for Multiple-Receiver Wireless Power Transfer Systems
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作者 Zhi-Hao Guo Shi-Er Dong 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第4期291-299,共9页
As different power has its own receivers,this paper analyzes and designs a multiple-receiver wireless power transfer(WPT)system systematically.The equivalent circuit model of the system is established to analyze the k... As different power has its own receivers,this paper analyzes and designs a multiple-receiver wireless power transfer(WPT)system systematically.The equivalent circuit model of the system is established to analyze the key parameters including transmitter power,receiver power,transmission efficiency,and each receiver power allocation.A control circuit is proposed to achieve the maximum transmission efficiency and transmitter power control and arbitrary receiver power allocation ratios for different receivers.Through the proposed control circuit,receivers with different loads can allocate appropriate power according to its power demand,the transmitter power and system efficiency do not vary with the change of the number of receivers.Finally,this control circuit is validated using a 130-kHz WPT system with three receivers whose power received is 3:10:12,and the overall system efficiency can reach as high as 55.5%. 展开更多
关键词 Multiple-receiver receiver power allocation transmitter power control wireless power transfer(WPT).
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使用WinSock控件和Internet Transfer控件的实例 被引量:2
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作者 毛速 《宁夏工程技术》 CAS 2003年第1期84-86,共3页
通过笔者编制的上机考试系统程序的实例,给出了在VisualBasic语言编程中使用WinSock控件进行客户端与服务器的通信和使用InternetTransfer控件控制文件的网络传输的几种特殊方法,说明了如何使用AD和Data控件对考生数据库和试题数据库进... 通过笔者编制的上机考试系统程序的实例,给出了在VisualBasic语言编程中使用WinSock控件进行客户端与服务器的通信和使用InternetTransfer控件控制文件的网络传输的几种特殊方法,说明了如何使用AD和Data控件对考生数据库和试题数据库进行管理,并对考试系统中试题的选择提出了可行的办法. 展开更多
关键词 VISUAL Basic WINSOCK控件 INTERNET transfer控件 ADO控件 DATA控件 计算机上机考试系统
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新一代实时控制网络平台(ControlNet)及其应用 被引量:9
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作者 吴乃优 吴小洪 +1 位作者 王晓初 胡志刚 《自动化仪表》 CAS 北大核心 2000年第5期19-21,共3页
详细介绍了ControlNet网络平台的特点、通信模式、信息交换及其应用场合。
关键词 网络平台 控制网络 实时控制 通信模式 数据传送
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BIFURCATIONS AND CHAOS CONTROL IN TCP-RED SYSTEM
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作者 刘芳 《Journal of Pharmaceutical Analysis》 SCIE CAS 2006年第1期1-5,共5页
Objective Analyzing the nonlinear dynamics of the TCP-RED congestion control system is of great importance. This study will help investigate the loss of stability in Internet and design a proper method for controlling... Objective Analyzing the nonlinear dynamics of the TCP-RED congestion control system is of great importance. This study will help investigate the loss of stability in Internet and design a proper method for controlling bifurcation and chaos in such system. Methods Based on bifurcation diagram, the effect of parameter on system performance is discussed. By using the state feedback and parameter variation strategy, a simple real time control method is proposed to modify the existing RED scheme. Results With our control method, the parametric sensitivity of RED mechanism is attenuated. Moreover, a sufficient condition on the robust stability of the system is also derived to adjust the parameters in TCP-RED system. Conclusion The proposed method has the advantages of simple implementation and unnecessary knowledge of the exact system. 展开更多
关键词 BIFURCATION CHAOS feedback control parameter variation congestion control transfer control protocol (TCP) random early detection (RED)
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Authentication and Access Control in RFID Based Logistics-customs Clearance Service Platform 被引量:4
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作者 Hui-Fang Deng Wen Deng +1 位作者 Han Li Hong-Ji Yang 《International Journal of Automation and computing》 EI 2010年第2期180-189,共10页
The content security requirements of a radio frequency identification (RFID) based logistics-customs clearance service platform (LCCSP) are analysed in this paper. Then, both the unified identity authentication an... The content security requirements of a radio frequency identification (RFID) based logistics-customs clearance service platform (LCCSP) are analysed in this paper. Then, both the unified identity authentication and the access control modules are designed according to those analyses. Finally, the unified identity authentication and the access control on the business level are implemented separately. In the unified identity authentication module, based on an improved Kerberos-based authentication approach, a new control transfer method is proposed to solve the sharing problem of tickets among different servers of different departments. In the access control module, the functions of access controls are divided into different granularities to make the access control management more flexible. Moreover, the access control module has significant reference value for user management in similar systems. 展开更多
关键词 Content security unified identity authentication control transfer access control logistics-customs clearance service platform (LCCSP).
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