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Dynamics and adaptive control of a dual-arm space robot with closed-loop constraints and uncertain inertial parameters 被引量:20
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作者 Ying-Hong Jia Quan Hu Shi-Jie Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第1期112-124,共13页
A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of contro... A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of controlling the po- sition and attitude of both the satellite base and the payload grasped by the manipulator end effectors. The equations of motion in reduced-order form for the constrained system are derived by incorporating the constraint equations in terms of accelerations into Kane's equations of the unconstrained system. Model analysis shows that the resulting equations perfectly meet the requirement of adaptive controller design. Consequently, by using an indirect approach, an adaptive control scheme is proposed to accomplish position/attitude trajectory tracking control with the uncertain parameters be- ing estimated on-line. The actuator redundancy due to the closed-loop constraints is utilized to minimize a weighted norm of the joint torques. Global asymptotic stability is proven by using Lyapunov's method, and simulation results are also presented to demonstrate the effectiveness of the proposed approach. 展开更多
关键词 Space robot Dynamics. Adaptive control closed-loop constraint Parameter uncertainty - Kane's equation
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Open-closed Loop ILC Corrected with Angle Relationship of Output Vectors for Tracking Control of Manipulator 被引量:8
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作者 WANG Hong-Bin WANG Yan 《自动化学报》 EI CSCD 北大核心 2010年第12期1758-1765,共8页
关键词 ILC 自动化 跟踪控制 仿真
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Closed-loop control of weld penetration in keyhole plasma arc welding 被引量:2
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作者 陈强 孙振国 +1 位作者 孙久文 王耀文 《中国有色金属学会会刊:英文版》 CSCD 2004年第1期116-120,共5页
To improve the penetrating ability and the welding quality of keyhole plasma arc welding, a novel penetration closed loop control system was established. In the system, welding current and plasma gas flow rate were se... To improve the penetrating ability and the welding quality of keyhole plasma arc welding, a novel penetration closed loop control system was established. In the system, welding current and plasma gas flow rate were selected as adjusting variables. The wavelet method was used to detect penetration status from welding arc voltage in real time. The control strategy of one keyhole per pulse was adapted to fulfill stable and high quality welding process. Experimental results show that the developed system can apparently increase the penetrating force of plasma arc and keyhole plasma arc welding is realized successfully in stainless steel with 10 mm in thickness. Moreover, the disturbances of gradual change and break change from 3 mm to 6 mm in thickness are come over due to the good response property of the developed system. 展开更多
关键词 焊缝 熔深 闭环控制 等离子弧焊 PAW
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An Implanted Closed-loop Chip System for Heart Rate Control:System Design and Effects in Conscious Rats 被引量:3
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作者 Yuxuan Zhou Yuan Yuan +4 位作者 Juan Gao Ling Yang Feng Zhang Guoqing Zhu Xingya Gao 《The Journal of Biomedical Research》 CAS 2010年第2期107-114,共8页
Objective: To evaluate the efficiency of an implanted chip system for the control of heart rate (HR). Methods: The HR was recorded in six conscious Sprague-Dawley (SD) rats. An implanted chip system was designed... Objective: To evaluate the efficiency of an implanted chip system for the control of heart rate (HR). Methods: The HR was recorded in six conscious Sprague-Dawley (SD) rats. An implanted chip system was designed to regulate the HR by stimulating the right cervical vagus nerve according to the feedback of real time HR. Each rat was subjected to 30-min regulation and 30-min recovery. The change of HR during the regulation period was compared with the control. The ECG was recorded during the experiment for 24 h. Results: The ECG signals were successfully recorded during the experiment. The HR was significantly decreased during the period of regulation compared with control (-79.3 ± 34.5, P 〈 0.01, n = 6) and then recovered to normal after regulation. Conclusion: The described implanted chip system can regulate the HR to a designated set point. 展开更多
关键词 closed-loop regulation implanted chip system set point heart rate vagus nerve stimulation Remote-controlled animal
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Open-plus-closed-loop control for chaotic motion of 3D rigid pendulum 被引量:2
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作者 戈新生 邹奎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第4期403-412,共10页
An open-plus-closed-loop (OPCL) control problem for the chaotic motion of a 3D rigid pendulum subjected to a constant gravitationM force is studied. The 3D rigid pendulum is assumed to be consist of a rigid body sup... An open-plus-closed-loop (OPCL) control problem for the chaotic motion of a 3D rigid pendulum subjected to a constant gravitationM force is studied. The 3D rigid pendulum is assumed to be consist of a rigid body supported by a fixed and frictionless pivot with three rotational degrees. In order to avoid the singular phenomenon of Euler's angular velocity equation, the quaternion kinematic equation is used to describe the motion of the 3D rigid pendulum. An OPCL controller for chaotic motion of a 3D rigid pendulum at equilibrium position is designed. This OPCL controller contains two parts: the open-loop part to construct an ideal trajectory and the closed-loop part to stabilize the 3D rigid pendulum. Simulation results show that the controller is effective and efficient. 展开更多
关键词 3D rigid pendulum QUATERNION chaotic motion Poincar section open-plus-closed-loop (OPCL) control
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Application of Single Neuron Adaptive PID Regulators with Auto-tuning Gain in Industrial Parameter(Pressure)Closed-loop Process Control Systems 被引量:1
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作者 Shaoyuan Sun Huade Li +1 位作者 Bin Qian Jianping Wei(Information Engineering School, University of Science and Technology Beijing, Beijing 100083, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第2期152-153,共2页
A type of single neuron adaptive PID regulator with auto-tuning gain is proposed and applied to the work control of fans, waterpumps and air-pressers etc. in Handan Iron & Steel Compel China. The robusthess of ind... A type of single neuron adaptive PID regulator with auto-tuning gain is proposed and applied to the work control of fans, waterpumps and air-pressers etc. in Handan Iron & Steel Compel China. The robusthess of induStrial parameter closed-loop process controlsystems is improved, and the work quality of the systems bettered. 展开更多
关键词 single neuron GAIN adaptiVe PID regulator pressure closed-loop control
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Study on a Closed-Loop Air-Fuel Control System of Gasoline Engines by Simulation
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作者 张付军 赵长禄 +1 位作者 黄英 郝利军 《Journal of Beijing Institute of Technology》 EI CAS 2003年第3期296-301,共6页
In order to study the factors that influence the air fuel ratio(A/F), the amplitude and frequency of A/F fluctuation, to reform the control strategy, and to improve the efficiency of three way catalyst(TWC), a model... In order to study the factors that influence the air fuel ratio(A/F), the amplitude and frequency of A/F fluctuation, to reform the control strategy, and to improve the efficiency of three way catalyst(TWC), a model of closed loop control system including the engine, air fuel mixing and transportation, oxygen sensor and controller, etc., is developed. Various factors that influence the A/F control are studied by simulation. The simulation results show that the reference voltage of oxygen sensor will influence the mean value of A/F ratio, the controller parameters will influence the amplitude of A/F fluctuation, and the operating conditions of the engine determine the frequency of A/F fluctuations, the amplitude of A/F fluctuation can be reduced to within demanded values by logical selection of the signal acquisition method and controller parameters. Higher A/F fluctuation frequency under high speed and load can be reduced through software delay in the controller. The A/F closed loop control system based on the simulation results, accompanied with a rare earth element TWC, gives a better efficiency of conversion against harmful emissions. 展开更多
关键词 air fuel ratio closed loop control SIMULATION
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A double closed loop APFC control with feed-forward
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作者 YAN Wen-hua WANG Xiao-peng YU Peng-fei 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第3期264-270,共7页
In order to improve the steady state performance,dynamic response and power factor of traditional power factor correction(PFC)digital control method and reduce the harmonic distortion of input current,a double closed ... In order to improve the steady state performance,dynamic response and power factor of traditional power factor correction(PFC)digital control method and reduce the harmonic distortion of input current,a double closed loop active power factorcorrection(APFC)control method with feed-forward is proposed.Firstly,the small signal model of Boost PFC control systemis built and the system transfer function is deduced,and then the parameters of the main device with Boost topology is estimated.By means of the feed-forward,the system can quickly respond to the change in input voltage.Furthermore,the use ofvoltage loop and current loop can achieve input current and output voltage regulation Simulink modeling shows that this methodcan effectively control the output voltage in case of input voltage largely fluctuating,improve the system dynamic response abilityand input power factor,and reduce the input current harmonic distortion 展开更多
关键词 active power factor correction FEED-FORWARD double closed loop control transfer function
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Interference Management for DS-CDMA Systems through Closed-Loop Power Control, Base Station Assignment, and Beamforming 被引量:1
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作者 Mohamad Dosaranian Moghadam Hamidreza Bakhshi Gholamreza Dadashzadeh 《Wireless Sensor Network》 2010年第6期472-482,共11页
In this paper, we propose a smart step closed-loop power control (SSPC) algorithm and a base station assignment method based on minimizing the transmitter power (BSA-MTP) technique in a direct sequence-code division m... In this paper, we propose a smart step closed-loop power control (SSPC) algorithm and a base station assignment method based on minimizing the transmitter power (BSA-MTP) technique in a direct sequence-code division multiple access (DS-CDMA) receiver with frequency-selective Rayleigh fading. This receiver consists of three stages. In the first stage, with constrained least mean squared (CLMS) algorithm, the desired users’ signal in an arbitrary path is passed and the inter-path interference (IPI) is reduced in other paths in each RAKE finger. Also in this stage, the multiple access interference (MAI) from other users is reduced. Thus, the matched filter (MF) can use for more reduction of the IPI and MAI in each RAKE finger in the second stage. Also in the third stage, the output signals from the matched filters are combined according to the conventional maximal ratio combining (MRC) principle and then are fed into the decision circuit of the desired user. The simulation results indicate that the SSPC algorithm and the BSA-MTP technique can significantly reduce the network bit error rate (BER) compared to the other methods. Also, we observe that significant savings in total transmit power (TTP) are possible with our methods. 展开更多
关键词 Adaptive Beamforming Antenna Array Base Station ASSIGNMENT closed-loop Power control Constrained LMS DS-CDMA
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Safety Assessment of Closed-Loop Level Crossing Control Systems by Means of STAMP(Systems-Theoretic Accident Model and Processes)
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作者 Tetsuya TAKATA Akira ASANO Hideo NAKAMURA 《Journal of Traffic and Transportation Engineering》 2018年第5期241-254,共14页
There have been a large number of accidents at level crossings of railways and this has been considered to be a significant issue to be solved for the realization of safe and stable railway transport.A conventional le... There have been a large number of accidents at level crossings of railways and this has been considered to be a significant issue to be solved for the realization of safe and stable railway transport.A conventional level crossing control system is characterized by the use of two types of electronic train detectors;one detects a train approaching to a level crossing section and the other then detects the train having left the level crossing.By contrast,closed-loop level crossing control systems in which level crossing control equipment and train-borne equipment communicate with each other have been advocated and are expected to serve as an effective solution to the abovementioned issue.This paper describes the following three types of closed-loop level crossing control systems:decentralized level crossing control system,fully-centralized comprehensive level crossing control system and fully-centralized individual level crossing control system.This paper then assesses the safety of these systems in comparison to the conventional level crossing control system.For the purpose of the assessment of their safety,a new accident analysis model called STAMP(systems theoretic accident model and processes)that is suitable for software intensive systems is used to clarify the advantage of the proposed three types of level crossing control systems in terms of safety. 展开更多
关键词 Level CROSSING control railway signaling closed loop control method safety assessment STAMP
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Model Reference Adaptive Control for Switched Systems with Closed-loop Reference Model Under Arbitrary Switching
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作者 Hao Yang Jing Xie Jun Zhao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第3期35-42,共8页
This paper explores the model reference adaptive control problem for a class of switched linear systems under arbitrary switching with no need for the measurability of the system state.Based on the state of reference ... This paper explores the model reference adaptive control problem for a class of switched linear systems under arbitrary switching with no need for the measurability of the system state.Based on the state of reference model and the measurable output error, adaptive laws and controllers are designed for switched systems.Each subsystem may have its individual reference model and controller, which increases the design flexibility.The introduction of the closed-loop reference model is to get a better transient performance of the whole switched systems.A numerical example is provided to verify the effectiveness of the main results. 展开更多
关键词 SWITCHED systems MODEL REFERENCE adaptive control common LYAPUNOV function arbitrary switching the closed-loop REFERENCE MODEL
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A simulation program for demonstration and analysis of closed loop negative feedback control
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作者 Thomas Scott Deering Paul 《通讯和计算机(中英文版)》 2009年第7期6-15,共10页
关键词 计算机仿真 仿真程序 模拟 控制
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Joint Closed-Loop Power Control and Adaptive Beamforming for Wireless Networks with Antenna Arrays in a 2D Urban Environment
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作者 Mohamad Dosaranian Moghadam Hamidreza Bakhshi Gholamreza Dadashzadeh 《Wireless Sensor Network》 2010年第11期869-878,共10页
The interference reduction capability of antenna arrays and the power control algorithms have been considered separately as means to decrease the interference in wireless communication networks. In this paper, we prop... The interference reduction capability of antenna arrays and the power control algorithms have been considered separately as means to decrease the interference in wireless communication networks. In this paper, we propose smart step closed-loop power control (SSPC) algorithm in wireless networks in a 2D urban environment with constrained least mean squared (CLMS) algorithm. This algorithm is capable of efficiently adapting according to the environment and able to permanently maintain the chosen frequency response in the look direction while minimizing the output power of the array. Also, we present switched-beam (SB) technique for enhancing signal to interference plus noise ratio (SINR) in wireless networks. Also, we study an analytical approach for the evaluation of the impact of power control error (PCE) on wireless networks in a 2D urban environment. The simulation results indicate that the convergence speed of the SSPC algorithm is faster than other algorithms. Also, we observe that significant saving in total transmit power (TTP) are possible with our proposed algorithm. Finally, we discuss three parameters of the PCE, number of antenna elements, and path-loss exponent and their effects on capacity of the system via some computer simulations. 展开更多
关键词 Adaptive Beamforming closed-loop POWER control Matched Filter Urban Signal Propagation Simulator POWER control Error
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Method of closed loop springback compensation for incremental sheet forming process 被引量:1
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作者 韩飞 莫健华 +1 位作者 龚攀 李敏 《Journal of Central South University》 SCIE EI CAS 2011年第5期1509-1517,共9页
The closed loop control model was built up for compensating the springback and enhancing the work piece precision.A coupled closed loop algorithm and a finite element method were developed to simulate and correct the ... The closed loop control model was built up for compensating the springback and enhancing the work piece precision.A coupled closed loop algorithm and a finite element method were developed to simulate and correct the springback of incremental sheet forming.A three-dimensional finite element model was established for simulation of springback in incremental sheet forming process.The closed loop algorithm of trajectory profile for the incremental sheet forming based on the wavelet transform combined with fast Fourier transform was constructed.The profile of processing tool path of shallow dishing with spherical surface was designed on the basis of the profile correction algorithm.The result shows that the algorithm can predict an ideal profile of processing track,and the springback error of incremental sheet forming is eliminated effectively.It has good convergence efficiency,and can improve the workpiece dimensional accuracy greatly. 展开更多
关键词 incremental sheet forming spingback numerical simulation closed loop control
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Synthesis identification analysis for closed loop system
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作者 WANG Jianhong RICARDO A.Ramirez-Mendoza 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第4期939-946,共8页
The existing theories for closed loop identification with the linear feedback controller are very mature.To apply the existed theories directly in the control field,we propose a new idea about replacing the original u... The existing theories for closed loop identification with the linear feedback controller are very mature.To apply the existed theories directly in the control field,we propose a new idea about replacing the original unknown and nonlinear feedback controller with one approximated linear controller,while guaranteeing the equivalent property for the obtained closed loop system.Based on some statistical correlation functions,one condition is derived to show the equivalent property between the approximated linear controller and the original nonlinear controller.The detailed explicit form,corresponding to the approximated linear controller,is also constructed.Furthermore,to give a complete analysis for closed loop identification,the cost function is rewritten as one extended expression,being convenient to understand.Then spectral estimation is introduced to identify the unknown plant in the closed loop system.Finally,the proposed theories are verified by one simulation example. 展开更多
关键词 synthesis analysis closed loop system simplified function equivalent controller
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Study the closed loop management system for the coal mines based on risk management
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作者 LI Xin-chun 《Journal of Coal Science & Engineering(China)》 2010年第2期215-220,共6页
In recent years, the coal safety has been become the urgent problem in China,and severe and fatal coal mine accidents occurred frequently.Must pay attention to coal safety management immediately, because the coal mine... In recent years, the coal safety has been become the urgent problem in China,and severe and fatal coal mine accidents occurred frequently.Must pay attention to coal safety management immediately, because the coal mine accidents not only caused serious economic losses to the country and people but also had negative impact on the society and politics.A closed loop management system was put forward to build to improve the coal safety management.The closed loop management system was formed four parts,identifying the hazard sources, classifying the hidden troubles hazard sources, the risk prealarm and risk control, and the evaluation system. 展开更多
关键词 closed loop management system risk control hazard sources
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Simulation of Automotive Engine Phase Signal Based on Closed-Loop Strategy
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作者 Runlong Cui Mingfa Yao Tao Chen 《Transactions of Tianjin University》 EI CAS 2017年第4期394-400,共7页
In this paper, an automotive engine phase signal simulation algorithm is proposed based on a closed-loop feedback strategy, and its corresponding model is built. The signal incentives are carried out in the front-end,... In this paper, an automotive engine phase signal simulation algorithm is proposed based on a closed-loop feedback strategy, and its corresponding model is built. The signal incentives are carried out in the front-end, and the synchronization capture and comparison are conducted in the back-end. The phase simulation of signal output is achieved using closed-loop strategy, which can effectively eliminate the inconsistency between crankshaft and camshaft phases, and thus the accuracy and flexibility of phase signal generation are guaranteed. Experimental results show that the proposed algorithm is real time, and the deviation of simulated signals from actual phase signals is small. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Crankshafts Engines
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地区级电网新能源AVC控制分析与应用
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作者 唐彬彬 缪雨薏 黄晓怡 《电工电气》 2024年第1期42-45,73,共5页
风能、光伏发电站参与调压控制,必要时可为电网提供紧急无功支撑,达到满足电能质量和降低网损的要求。阐述了地区级电网新能源AVC控制(Automatic Voltage Control)的原理及实际应用,总结归纳了新能源AVC控制并网接入的常见问题,通过35 k... 风能、光伏发电站参与调压控制,必要时可为电网提供紧急无功支撑,达到满足电能质量和降低网损的要求。阐述了地区级电网新能源AVC控制(Automatic Voltage Control)的原理及实际应用,总结归纳了新能源AVC控制并网接入的常见问题,通过35 kV新能源AVC子站接入地区级主站实例的综合实验,证明了新能源AVC控制在曲线下发、闭环控制策略及电压跟随等功能的有效性,同时在响应上具备较好的跟随性和快速性。 展开更多
关键词 新能源 avc控制 闭环控制
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Recent developments on applications of sequential loop closing and diagonal dominance control schemes to industrial multivariable system 被引量:4
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作者 A.H.Mazinan M.F.Kazemi 《Journal of Central South University》 SCIE EI CAS 2013年第12期3401-3420,共20页
With a focus on an industrial multivariable system, two subsystems including the flow and the level outputs are analysed and controlled, which have applicability in both real and academic environments. In such a case,... With a focus on an industrial multivariable system, two subsystems including the flow and the level outputs are analysed and controlled, which have applicability in both real and academic environments. In such a case, at first, each subsystem is distinctively represented by its model, since the outcomes point out that the chosen models have the same behavior as corresponding ones. Then, the industrial multivariable system and its presentation are achieved in line with the integration of these subsystems, since the interaction between them can not actually be ignored. To analyze the interaction presented, the Gershgorin bands need to be acquired, where the results are used to modify the system parameters to appropriate values. Subsequently, in the view of modeling results, the control concept in two different techniques including sequential loop closing control(SLCC) scheme and diagonal dominance control(DDC) schemes is proposed to implement on the system through the Profibus network, as long as the OPC(OLE for process control) server is utilized to communicate between the control schemes presented and the multivariable system. The real test scenarios are carried out and the corresponding outcomes in their present forms are acquired. In the same way, the proposed control schemes results are compared with each other, where the real consequences verify the validity of them in the field of the presented industrial multivariable system control. 展开更多
关键词 multivariable system diagonal dominance control sequential loop closing control Profibus network OPC server orifice relation interaction analysis Gershogerin bands non-minimum phase system
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老年髋关节置换术中实施丙泊酚闭环靶控输注麻醉的效果及对患者术后谵妄风险的影响 被引量:3
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作者 王亚群 邱新建 +3 位作者 彭杰成 王辉 汪东学 王玲 《临床和实验医学杂志》 2024年第10期1118-1120,F0003,共4页
目的研究老年髋关节置换术中实施丙泊酚闭环靶控输注麻醉的效果及对术后谵妄风险的影响。方法回顾性选取2020年1月至2023年1月入安庆市第一人民医院接受治疗的90例髋关节骨折老年患者,择期行髋关节置换术。参考麻醉方式不同分为A组、B组... 目的研究老年髋关节置换术中实施丙泊酚闭环靶控输注麻醉的效果及对术后谵妄风险的影响。方法回顾性选取2020年1月至2023年1月入安庆市第一人民医院接受治疗的90例髋关节骨折老年患者,择期行髋关节置换术。参考麻醉方式不同分为A组、B组和C组,每组各30例。A组给予丙泊酚闭环靶控持续输注麻醉,B组给予丙泊酚开环靶控持续输注麻醉,C组给予丙泊酚人工持续输注麻醉。比较3组患者的术中相关指标(麻醉时间、手术时间以及拔管时间)、麻醉相关指标(术中丙泊酚总计用量、术中维持泵调节次数)、血流动力学变化[麻醉诱导开始(T_(0))、插管(T_(1))、手术开始(T_(2))、手术结束(T_(3))、拔管(T_(4))的平均动脉压、心率以及脑电双频指数(BIS)值]情况、术后恢复情况及术后谵妄发生情况。结果(1)术中指标:3组患者麻醉时间、手术时间以及拔管时间比较,差异均无统计学意义(P>0.05)。(2)麻醉相关指标:A组患者术中丙泊酚总计用量、术中维持泵调节次数均明显低于B、C组,差异均有统计学意义(P<0.05);B组患者单位麻醉时间内丙泊酚用量、单位手术时间内丙泊酚用量均明显高于A、C组,差异均有统计学意义(P<0.05)。(3)血流动力学:A组T_(2)、T_(3)时平均动脉压均高于B组、C组,A组T_(4)时的平均动脉压更加接近于T_(0);3组患者不同时刻心率差异无统计学意义(P>0.05);A组T_(2)、T_(3)时BIS值均低于B组、C组,差异均有统计学意义(P<0.05)。(4)术后恢复情况:A组患者PACU停滞时间、自主呼吸恢复时间、指令反应恢复时间均明显低于B、C组,差异均有统计学意义(P<0.05)。(5)术后谵妄:A组患者术后谵妄发生率为16.67%,显著低于B、C组(40.00%、46.67%),差异均有统计学意义(P<0.05)。结论老年髋关节置换术中采用丙泊酚靶控输注麻醉可减少丙泊酚用量,术中生命体征更加平稳,可降低人工操作次数,术后麻醉苏醒更快,且术后谵妄发生率也更低,是老年患者首选的麻醉方案。 展开更多
关键词 髋关节置换术 老年人 闭环靶控输注 丙泊酚 谵妄
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