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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
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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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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
一系列 heteropolytungstates 被综合了并且作为催化剂利用了与水的过氧化氢催化本甲基酒精的氧化。结果显示三这些催化剂显示出控制反应的阶段转移催化作用的性质,并且他们有优秀催化能力到本甲基酒精的氧化。没有另外的副产品被气相... 一系列 heteropolytungstates 被综合了并且作为催化剂利用了与水的过氧化氢催化本甲基酒精的氧化。结果显示三这些催化剂显示出控制反应的阶段转移催化作用的性质,并且他们有优秀催化能力到本甲基酒精的氧化。没有另外的副产品被气相色谱检测。一旦过氧化氢完全被消费,催化剂从催化剂的溶剂,和结果猛抛再循环证明催化剂有高稳定性。 展开更多
关键词 异质多钨酸盐 苯甲醇 相转移催化剂 苯甲醛 过氧化氢
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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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Stimuli-responsive Membranes: Smart Tools for Controllable Mass-transfer and Separation Processes 被引量:18
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作者 褚良银 谢锐 巨晓洁 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期891-903,共13页
As emerging artificial biomimetic membranes, smart or intelligent membranes that are able to respond to environmental stimuli are attracting ever-increasing interests from various fields. Their permeation properties i... As emerging artificial biomimetic membranes, smart or intelligent membranes that are able to respond to environmental stimuli are attracting ever-increasing interests from various fields. Their permeation properties including hydraulic permeability and diffusional permeability can be dramatically controlled or adjusted self-regulatively in response to small chemical and/or physical stimuli in their environments. Such environmental stimuli-responsive smart membranes could find myriad applications in numerous fields ranging from controlled release to separations. Here the trans-membrane mass-transfer and membrane separation is introduced as the beginning to initiate the requirement of smart membranes, and then bio-inspired design of environmental stimuli-responsive smart membranes and four essential elements for smart membranes are introduced and discussed. Next, smart membrane types and their applications as smart tools for controllable mass-transfer in controlled release and separations are reviewed. The research topics in the near future are also suggested. 展开更多
关键词 智能工具 分离过程 跨膜传质 敏感膜 可控 环境刺激 渗透性能 刺激响应
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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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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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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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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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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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Pressure control strategy for pump motor energy transfer unit 被引量:2
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作者 姚静 Zhang Wei +2 位作者 Cao Xiaoming Zhao Guichun Sun Menghui 《High Technology Letters》 EI CAS 2019年第3期286-293,共8页
Multi-level pressure source system is a novel hydraulic system with distinct advantage of energy saving. In order to balance each pressure level of the multi-level pressure source system, a pump motor energy transfer ... Multi-level pressure source system is a novel hydraulic system with distinct advantage of energy saving. In order to balance each pressure level of the multi-level pressure source system, a pump motor energy transfer unit is usually equipped. However, the pump motor energy transfer has the characteristics of poor starting and low response, which cause long time of pressure adjustment and large pressure jitter when the transformer is switched to system suddenly and the motor-side pressure has pressure impact when rail of the pump-side is switched. To address these problems, this paper proposes a compound control strategy of feedforward compensation control with Fuzzy-PID to improve the controllability of the multi-level pressure source system. A test rig of the pump motor energy transfer unit is built and the controllability of compound controller and PID controller are compared. The experiment results show that, compared with the traditional PID, the adjustment time and the pressure impact are reduced by 20% and 25% with the proposed compound control strategy. Therefore, the presented compound control strategy can be used to improve starting performance and robustness of the pump motor energy transfer unit control system. 展开更多
关键词 HYDRAULIC system pump-motor ENERGY transfer unit PRESSURE control ENERGY SAVING
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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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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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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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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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Numerical Simulation and Control of Two-Phase Flow with Evaporation in a Vertical Tube Submitted to a Conjugate Heat Transfer 被引量:2
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作者 Ghazali Mebarki Samir Rahal 《Journal of Energy and Power Engineering》 2013年第7期1282-1292,共11页
关键词 控制参数 两相流 热蒸发 垂直管 数值仿真 共轭 管内 流动不稳定性
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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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Study of engaged performance regulation in controlled transfer clutch of 4WD car based on genetic sliding mode control
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作者 Zhang Yang Men Yongxin +1 位作者 Li Wei Ma Mingtu 《Engineering Sciences》 EI 2014年第5期38-44,共7页
This paper investigates an approach to improve the engagement quality of controlled transfer clutch mode in 4 wheel drive(WD) car from three considerations of reducing friction,smoothening responsiveness and alleviati... This paper investigates an approach to improve the engagement quality of controlled transfer clutch mode in 4 wheel drive(WD) car from three considerations of reducing friction,smoothening responsiveness and alleviating jerk.The method utilizes an improved sliding mode control with genetic algorithm instead of simplified mode to determine appropriate values of parameters in control close- loop.The simulation results show that the method is effective for improving the engagement quality of coupling satisfying different design needs for 4WD car,as well as robustness even if input torque is changed at a certain range. 展开更多
关键词 滑模控制 遗传算法 离合器 啮合性能 滑动模式控制 4轮驱动 传输控制 响应速度
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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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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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