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Study on the Interactivity of Controlled and Automatic Information Processing in L2 Reading
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作者 DONG Tiantian WANG Yong 《Sino-US English Teaching》 2024年第7期314-321,共8页
L2 reading is not only an important channel for people to obtain information and knowledge,but also the main way for people to learn a foreign language.Reading information processing can be divided into controlled pro... L2 reading is not only an important channel for people to obtain information and knowledge,but also the main way for people to learn a foreign language.Reading information processing can be divided into controlled processing and automatic processing.Controlled information processing is a conscious and resource-intensive processing model,while automatic information processing is an unconscious and automatic processing model.This study investigates the characteristics and interactivity of controlled and automatic information processing in L2 reading,and explores the roles of controlled and automatic information processing strategies in improving L2 reading ability.The findings are as follows:(a)controlled and automatic information processing is interactive in L2 reading;and(b)the uses of controlled and automatic information processing strategies are beneficial to the improvement of the reading ability of L2 learners.This study has important theoretical and practical value in improving the efficiency of L2 reading teaching and learning. 展开更多
关键词 L2 reading controlled information processing automatic information processing interactivity
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Application Strategies of Automatic Addressable Single-Lamp Control Technology in Tunnel Lighting
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作者 Huiyan Yang 《Journal of World Architecture》 2024年第2期90-95,共6页
The article mainly studies the application strategy of automatic addressable single-lamp control technology in tunnel lighting.It encompasses an introduction to this technology,an analysis of the tunnel lighting syste... The article mainly studies the application strategy of automatic addressable single-lamp control technology in tunnel lighting.It encompasses an introduction to this technology,an analysis of the tunnel lighting system using automatic addressable single-lamp control technology,and outlines the main development direction for this technology in modern tunnel lighting.The aim is to offer insights that can inform the rational deployment of this technology,thereby enhancing the lighting control effectiveness in modern tunnels and meeting their specific lighting requirements more effectively. 展开更多
关键词 Tunnel lighting automatic addressable single-lamp control technology System design Cascade control
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Anti-interference Strategy of 20-Hi Cold Mill Automatic Gauge Control
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作者 ZHANG Zhen ZHU Bingquan CHEN Haifeng 《Instrumentation》 2022年第3期10-18,共9页
Automatic gauge control(AGC in the article)is the key technology of product thickness accuracy and flatness quality in modern cold rolling mill.Most traditional AGC control algorithms need stable external system condi... Automatic gauge control(AGC in the article)is the key technology of product thickness accuracy and flatness quality in modern cold rolling mill.Most traditional AGC control algorithms need stable external system conditions and hard to stabilize under complex interference that meets coverage requirements.This paper presents a new anti-interference strategy for AGC control of 20-Hi cold reversing mill.The proposed algorithm introduces a united dynamic weights algorithm of feed forward-mass flow to avoid the complex interference problem in AGC control,the relevant control strategy is provided to eliminate the adverse effects.At the same time,the D-value between feed forward-mass flow pre-computation and thickness measurement deviation is dynamic compared,the final gap position regulation is calculated by developing a set of united dynamic weights between feed forward control and mass flow control.Finally,the output of controllers is sent to actuator though a constant rate smoothing.The proposed strategy is compared with conventional AGC control on Experimental platform and project application,the results show that the proposed strategy is more stable than comparison method and majority of system uncertainty produced by mentioned interference is significantly eliminated. 展开更多
关键词 20-Hi Cold Mill Complex Interference AGC control United Dynamic Weights anti-interference
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Automatic SOC Equalization Strategy of Energy Storage Units with DC Microgrid Bus Voltage Support
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作者 Jingjing Tian Shenglin Mo +1 位作者 Feng Zhao Xiaoqiang Chen 《Energy Engineering》 EI 2024年第2期439-459,共21页
In this paper,an improved sag control strategy based on automatic SOC equalization is proposed to solve the problems of slow SOC equalization and excessive bus voltage fluctuation amplitude and offset caused by load a... In this paper,an improved sag control strategy based on automatic SOC equalization is proposed to solve the problems of slow SOC equalization and excessive bus voltage fluctuation amplitude and offset caused by load and PV power variations in a stand-alone DC microgrid.The strategy includes primary and secondary control.Among them,the primary control suppresses the DC microgrid voltage fluctuation through the I and II section control,and the secondary control aims to correct the P-U curve of the energy storage system and the PV system,thus reducing the steady-state bus voltage excursion.The simulation results demonstrate that the proposed control strategy effectively achieves SOC balancing and enhances the immunity of bus voltage.The proposed strategy improves the voltage fluctuation suppression ability by approximately 39.4%and 43.1%under the PV power and load power fluctuation conditions,respectively.Furthermore,the steady-state deviation of the bus voltage,△U_(dc) is only 0.01–0.1 V,ensuring stable operation of the DC microgrid in fluctuating power environments. 展开更多
关键词 automatic equalization independent DC microgrid improve droop control secondary control state of charge
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A low-noise X-band microwave source with digital automatic frequency control for electron paramagnetic resonance spectroscopy
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作者 贺羽 康润琪 +1 位作者 石致富 荣星 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期46-51,共6页
We report a new design of microwave source for X-band electron paramagnetic resonance spectrometer.The microwave source is equipped with a digital automatic frequency control circuit.The parameters of the digital auto... We report a new design of microwave source for X-band electron paramagnetic resonance spectrometer.The microwave source is equipped with a digital automatic frequency control circuit.The parameters of the digital automatic frequency control circuit can be flexibly configured for different experimental conditions,such as the input powers or the quality factors of the resonator.The configurability makes the microwave source universally compatible and greatly extends its application.To demonstrate the ability of adapting to various experimental conditions,the microwave source is tested by varying the input powers and the quality factors of the resonator.A satisfactory phase noise as low as-135 d Bc/Hz at 100-k Hz offset from the center frequency is achieved,due to the use of a phase-locked dielectric resonator oscillator and a direct digital synthesizer.Continuous-wave electron paramagnetic resonance experiments are conducted to examine the performance of the microwave source.The outstanding performance shows a prospect of wide applications of the microwave source in numerous fields of science. 展开更多
关键词 electron paramagnetic resonance X-BAND microwave source automatic frequency control
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Design and Simulation of an Audio Signal Alerting and Automatic Control System
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作者 Winfred Adjardjah John Awuah Addor +1 位作者 Wisdom Opare Isaac Mensah Ayipeh 《Communications and Network》 2023年第4期98-119,共22页
A large part of our daily lives is spent with audio information. Massive obstacles are frequently presented by the colossal amounts of acoustic information and the incredibly quick processing times. This results in th... A large part of our daily lives is spent with audio information. Massive obstacles are frequently presented by the colossal amounts of acoustic information and the incredibly quick processing times. This results in the need for applications and methodologies that are capable of automatically analyzing these contents. These technologies can be applied in automatic contentanalysis and emergency response systems. Breaks in manual communication usually occur in emergencies leading to accidents and equipment damage. The audio signal does a good job by sending a signal underground, which warrants action from an emergency management team at the surface. This paper, therefore, seeks to design and simulate an audio signal alerting and automatic control system using Unity Pro XL to substitute manual communication of emergencies and manual control of equipment. Sound data were trained using the neural network technique of machine learning. The metrics used are Fast Fourier transform magnitude, zero crossing rate, root mean square, and percentage error. Sounds were detected with an error of approximately 17%;thus, the system can detect sounds with an accuracy of 83%. With more data training, the system can detect sounds with minimal or no error. The paper, therefore, has critical policy implications about communication, safety, and health for underground mine. 展开更多
关键词 Emergency Response Emergency Management Team Audio Signal Alerting automatic control System Uni Pro XL Manual Communication Fast Fourier Transform Magnitude Zero Crossing Rate Root Means Square
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Fuzzy Controller-Based Design and Simulation of an Automatic Parking System
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作者 Meiyan Gao Yuanzhou Wei +4 位作者 Ya He Dan Zhang Yuanhao Tian Bolin Huang Changyang Zheng 《Journal of Software Engineering and Applications》 2023年第9期505-520,共16页
With the development of automatic driving and fuzzy theory, people pay more and more attention to the application of fuzzy logic in engineering technology. The automatic parking module in the automatic driving system ... With the development of automatic driving and fuzzy theory, people pay more and more attention to the application of fuzzy logic in engineering technology. The automatic parking module in the automatic driving system has always been the focus of research. Automatic parking modules can greatly assist drivers in parking operations, greatly reduce parking difficulties and make people more convenient and fast parking. In this paper, an automatic parking system based on the fuzzy controller is proposed. The fuzzy controller of automatic parking system is constructed by using fuzzy theory, and the robustness of the whole system is examined by fuzzy logic. Firstly, the vehicle motion rules and trajectory changes are analyzed in detail, and the real parking lot model is simulated. Then, the input and output variables of the whole system are analyzed by fuzzy theory and the membership function is constructed. Based on the experience of human experts, the parking rules are tested and summarized, and a reasonable and practical rule base is established. Finally, MATLAB is used to code, build the visual interface of parking lot and vehicles, and draw the cyclic iterative function to detect the vehicle position and direction angle, so as to act as a sensor. The results show that using a fuzzy controller to construct an automatic parking system can effectively improve the parking level. 展开更多
关键词 automatic Parking controller Theory Fuzzy Logic MATLAB System Optimization
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GUIDANCE AND CONTROL FOR AUTOMATIC LANDING OF UAV 被引量:1
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作者 曹云峰 陶勇 沈勇璋 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期229-235,共7页
A scheme of guidance and control is presented to meet the requirements for automatic landing of unmanned aerial vehicles (UAVs) based on the airborne digital flight control system and radio tracker on ground station. ... A scheme of guidance and control is presented to meet the requirements for automatic landing of unmanned aerial vehicles (UAVs) based on the airborne digital flight control system and radio tracker on ground station. An automatic landing system is realized for an unmanned aerial vehicle. The results of real time simulation and flight test are given to illustrate the effectiveness and availability of the scheme. Results meet all the requirements for automatic landing of the unmanned aerial vehicle. 展开更多
关键词 automatic landing unmanned aerial vehicle GUIDANCE NAVIGATION flight control
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Automatic Control of Automobile Transmission Performance Test Stand
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作者 阎清东 项昌乐 冯永存 《Journal of Beijing Institute of Technology》 EI CAS 1998年第2期178-183,共6页
To realize automatic control of automobile transmission performance test stand Methods The automatic control technique of the lubricant temperature,the program- controll- edautomaticshifting of the transmission,the c... To realize automatic control of automobile transmission performance test stand Methods The automatic control technique of the lubricant temperature,the program- controll- edautomaticshifting of the transmission,the continuous adjusting of revolution speed and load, data-acquisition and data real-time processing were adopted.Results The lubricant temperature was controlled at the set temperature ±2℃.The automatic shifting of the trans- mission is simple,reliable and accurate.The automatic adjusting of load and rotation speed is rapidandaccurate,the torque divergence is ±1N·m,the rotation speed divergence is ±5r/min Conclusion The four kinds of techniques are applied into the automobile transmission perfor- mance test stand successfully. mancetest stand successfully. 展开更多
关键词 automobile transmission performance test computer-aided test automatic control
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OPTIMAL CONTROL APPLIED IN AUTOMATIC CLUTCH ENGAGEMENTS OF VEHICLES 被引量:13
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作者 Sun Chengshun Zhang Jianwu School of Mechanical and Power Engineering,Shanghai Jiaotong University,Shanghai 200030, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第2期280-283,共4页
Start-up working condition is the key to the research of optimal engagementof automatic clutch for AMT. In order to guarantee an ideal dynamic performance of the clutchengagement, an optimal controller is designed by ... Start-up working condition is the key to the research of optimal engagementof automatic clutch for AMT. In order to guarantee an ideal dynamic performance of the clutchengagement, an optimal controller is designed by considering throttle angle, engine speed, gearratio, vehicle acceleration and road condition. The minimum value principle is also introduced toachieve an optimal dynamic performance of the nonlinear system compromised in friction plate wearand vehicle drive quality. The optimal trajectory of the clutch engagement can be described in theform of explicit and analytical expressions and characterized by the deterministic and accuratecontrol strategy in stead of indeterministic and soft control techniques which need thousands ofexperiments. For validation of the controller, test work is carried out for the automated clutchengagements in a commercial car with an traditional mechanical transmission, a hydraulic actuator, agroup of sensors and a portable computer system. It is shown through experiments that dynamicbehaviors of the clutch engagement operated by the optimal control are more effective and efficientthan those by fuzzy control. 展开更多
关键词 automatic clutch Optimal control Nonlinear system dynamics
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Guidance and Control Techniques of Carrier-Based Aircraft for Automatic Carrier Landing 被引量:9
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作者 Zhen Ziyang Zhang Zhibin Zhang Junhong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第6期600-608,共9页
We summarize the guidance and control techniques of automatic carrier landing for carrier-based aircraft.First,we analyze the carrier landing operations of the manned fixed-wing aircraft,unmanned fixed-wing aircraft a... We summarize the guidance and control techniques of automatic carrier landing for carrier-based aircraft.First,we analyze the carrier landing operations of the manned fixed-wing aircraft,unmanned fixed-wing aircraft and helicopters.Second,we look into the navigation and guidance system and the flight control methods for current different aircraft.Finally,we draw several conclusions of the development prospects for aircraft carrier landing,including the precision landing control techniques,precision approach and landing guidance techniques,and adaptive,reconfigurable and intelligent flight control techniques. 展开更多
关键词 carrier-based aircraft automatic carrier landing GUIDANCE flight control
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Adaptive Clutch Engaging Process Control for Automatic Mechanical Transmission 被引量:12
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作者 刘海鸥 陈慧岩 +1 位作者 丁华荣 何忠波 《Journal of Beijing Institute of Technology》 EI CAS 2005年第2期170-174,共5页
Based on detail analysis of clutch engaging process control targets and adaptive demands, a control strategy which is based on speed signal, different from that of based on main clutch displacement signal, is put forw... Based on detail analysis of clutch engaging process control targets and adaptive demands, a control strategy which is based on speed signal, different from that of based on main clutch displacement signal, is put forward. It considers both jerk and slipping work which are the most commonly used quality evaluating indexes of vehicle starting phase. The adaptive control system and its reference model are discussed profoundly. Taking the adaptability to different starting gears and different road conditions as examples, some proving field test records are shown to illustrate the main clutch adaptive control strategy at starting phase. Proving field test gives acceptable results. 展开更多
关键词 automatic mechanical transmission(AMT) transmission technology adaptive control main clutch engagement
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Automatic Carrier Landing Control for Unmanned Aerial Vehicles Based on Preview Control 被引量:9
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作者 Zhen Ziyang Ma Kun Bhatia Ajeet Kumar 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第4期413-419,共7页
For carrier-based unmanned aerial vehicles(UAVs),one of the important problems is the design of an automatic carrier landing system(ACLS)that would enable the UAVs to accomplish autolanding on the aircraft carrier.How... For carrier-based unmanned aerial vehicles(UAVs),one of the important problems is the design of an automatic carrier landing system(ACLS)that would enable the UAVs to accomplish autolanding on the aircraft carrier.However,due to the movements of the flight deck with six degree-of-freedom,the autolanding becomes sophisticated.To solve this problem,an accurate and effective ACLS is developed,which is composed of an optimal preview control based flight control system and a Kalman filter based deck motion predictor.The preview control fuses the future information of the reference glide slope to improve landing precision.The reference glide slope is normally a straight line.However,the deck motion will change the position of the ideal landing point,and tracking the ideal straight glide slope may cause landing failure.Therefore,the predictive deck motion information from the deck motion predictor is used to correct the reference glide slope,which decreases the dispersion around the desired landing point.Finally,simulations are carried out to verify the performance of the designed ACLS based on a nonlinear UAV model. 展开更多
关键词 carrier-based unmanned aerial vehicles optimal preview control automatic carrier landing system deck motion predictor
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Design of a Proportional-Integral-Derivative Controller for an Automatic Generation Control of Multi-area Power Thermal Systems Using Firefly Algorithm 被引量:5
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作者 K.Jagatheesan B.Anand +3 位作者 Sourav Samanta Nilanjan Dey Amira S.Ashour Valentina E.Balas 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第2期503-515,共13页
Essentially, it is significant to supply the consumer with reliable and sufficient power. Since, power quality is measured by the consistency in frequency and power flow between control areas. Thus, in a power system ... Essentially, it is significant to supply the consumer with reliable and sufficient power. Since, power quality is measured by the consistency in frequency and power flow between control areas. Thus, in a power system operation and control,automatic generation control(AGC) plays a crucial role. In this paper, multi-area(Five areas: area 1, area 2, area 3, area 4 and area 5) reheat thermal power systems are considered with proportional-integral-derivative(PID) controller as a supplementary controller. Each area in the investigated power system is equipped with appropriate governor unit, turbine with reheater unit, generator and speed regulator unit. The PID controller parameters are optimized by considering nature bio-inspired firefly algorithm(FFA). The experimental results demonstrated the comparison of the proposed system performance(FFA-PID)with optimized PID controller based genetic algorithm(GAPID) and particle swarm optimization(PSO) technique(PSOPID) for the same investigated power system. The results proved the efficiency of employing the integral time absolute error(ITAE) cost function with one percent step load perturbation(1 % SLP) in area 1. The proposed system based FFA achieved the least settling time compared to using the GA or the PSO algorithms, while, it attained good results with respect to the peak overshoot/undershoot. In addition, the FFA performance is improved with the increased number of iterations which outperformed the other optimization algorithms based controller. 展开更多
关键词 automatic generation control(AGC) FIREFLY ALGORITHM GENETIC algorithm(GA) particle SWARM optimization(PSO) proportional-integral-derivative(PID) controller
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Monitor automatic gauge control strategy with a Smith predictor for steel strip rolling 被引量:10
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作者 Dianhua Zhang Hao Zhang +1 位作者 Tao Sun Xu Li 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期827-832,共6页
The simplified transfer function diagram block for a monitor automatic gauge control (Mon-AGC) system of strip steel rolling process was investigated. The new notion of strip sample length was given. In this way, th... The simplified transfer function diagram block for a monitor automatic gauge control (Mon-AGC) system of strip steel rolling process was investigated. The new notion of strip sample length was given. In this way, the delay time varying with the rolling speed was evaded. After a Smith predictor was used to monitor the AGC system, the control laws were deduced for both proportional and integral regulators. The control strategies showed that by choosing the controller parameter P=∞ for both control algo- rithms each regulator could compensate the whole strip gage error in the first control step. The result shows that the integral algo- rithm is more controllable for the system regulating process and has a better steady-state precision than the proportional regulator. Compared with the traditional control strategy, the new control laws have a faster response speed and a hieher steadv-state precision. 展开更多
关键词 time delay system Smith predictor (SP) automatic gauge control steel strip rollling
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A Novel Cascaded PID Controller for Automatic Generation Control Analysis With Renewable Sources 被引量:5
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作者 Aurobindo Behera Tapas Kumar Panigrahi +1 位作者 PrakashK·Ray Arun Kumar Sahoo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1438-1451,共14页
Present day power scenarios demand a high quality uninterrupted power supply and needs environmental issues to be addressed. Both concerns can be dealt with by the introduction of the renewable sources to the existing... Present day power scenarios demand a high quality uninterrupted power supply and needs environmental issues to be addressed. Both concerns can be dealt with by the introduction of the renewable sources to the existing power system. Thus, automatic generation control(AGC) with diverse renewable sources and a modified-cascaded controller are presented in the paper.Also, a new hybrid scheme of the improved teaching learning based optimization-differential evolution(hITLBO-DE) algorithm is applied for providing optimization of controller parameters. A study of the system with a technique such as TLBO applied to a proportional integral derivative(PID), integral double derivative(IDD) and PIDD is compared to hITLBO-DE tuned cascaded controller with dynamic load change.The suggested methodology has been extensively applied to a 2-area system with a diverse source power system with various operation time non-linearities such as dead-band of, generation rate constraint and reheat thermal units. The multi-area system with reheat thermal plants, hydel plants and a unit of a wind-diesel combination is tested with the cascaded controller scheme with a different controller setting for each area. The variation of the load is taken within 1% to 5% of the connected load and robustness analysis is shown by modifying essential factors simultaneously by± 30%. Finally, the proposed scheme of controller and optimization technique is also tested with a 5-equal area thermal system with non-linearities. The simulation results demonstrate the superiority of the proposed controller and algorithm under a dynamically changing load. 展开更多
关键词 automatic generation control(AGC) cascaded controlLER hybrid improved teaching learning based optimization-differential evolution(hITLBO-DE) algorithm INTEGRAL of SQUARE time multiplied by SQUARE error(ISTSE)
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H_∞ Preview Control for Automatic Carrier Landing 被引量:2
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作者 FARHAN Masood XUE Yixuan' +1 位作者 ZHEN Ziyang YANG Liuqing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第6期919-926,共8页
This paper focuses on the application of H_∞preview control in automatic carrier landing system(ACLS)for carrier-based aircraft.Due to the mutual movement between aircraft and carrier,the landing process becomes cons... This paper focuses on the application of H_∞preview control in automatic carrier landing system(ACLS)for carrier-based aircraft.Due to the mutual movement between aircraft and carrier,the landing process becomes considerably more challenging compared to a conventional runway landing.ACLS systems mitigate this by predicting deck motion and generating ideal glide slope path for tracking.Although,this predicted glide slope information is available in advance,conventional control structures are still unable to use this future information.H_∞preview control has the ability to utilize this future information for improving tracking response and disturbance rejection.The process of incorporating preview information into ACLS framework and synthesizing the H_∞preview controller is presented.The methodology is verified using the example of F/A-18 automatic carrier landing problem and results are presented. 展开更多
关键词 H∞control preview control carrierbased aircraft automatic carrier landing robust preview control
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High-Speed Trains Automatic Operation with Protection Constraints: A Resilient Nonlinear Gain-based Feedback Control Approach 被引量:2
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作者 Shigen Gao Yuhan Hou +2 位作者 Hairong Dong Sebastian Stichel Bin Ning 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期992-999,共8页
This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of gua... This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of guaranteeing,under some proper non-restrictive initial conditions,the protection constraints control raised by the distance-to-go(moving authority)curve and automatic train protection in practice.A new hyperbolic tangent function-based model is presented to mimic the whole operation process of high-speed trains.The proposed feedback control methods are easily implementable and computationally inexpensive because the presence of only two feedback gains guarantee satisfactory tracking performance and closed-loop stability,no adaptations of unknown parameters,function approximation of unknown nonlinearities,and attenuation of external disturbances in the proposed control strategies.Finally,rigorous proofs and comparative simulation results are given to demonstrate the effectiveness of the proposed approaches. 展开更多
关键词 automatic TRAIN operation high-speed TRAIN nonlinear GAIN feedback PROTECTION CONSTRAINT resilient control
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Percutaneous endoscopic gastrostomy under steadypressure automatically controlled endoscopy:First clinicalseries 被引量:2
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作者 Hiroyuki Imaeda Kiyokazu Nakajima +14 位作者 Naoki Hosoe Masanori Nakahara Shinichiro Zushi Motohiko Kato Kazuhiro Kashiwagi Yasushi Matsumoto Kayoko Kimura Rieko Nakamura Norihito Wada Masahiko Tsujii Naohisa Yahagi Toshifumi Hibi Takanori Kanai Tetsuo Takehara Haruhiko Ogata 《World Journal of Gastrointestinal Endoscopy》 CAS 2016年第3期186-191,共6页
AIM: To elucidate the safety of percutaneous endoscopic gastrostomy(PEG) under steady pressure automatically controlled endoscopy(SPACE) using carbon dioxide(CO_2).METHODS: Nine patients underwent PEG with a modified ... AIM: To elucidate the safety of percutaneous endoscopic gastrostomy(PEG) under steady pressure automatically controlled endoscopy(SPACE) using carbon dioxide(CO_2).METHODS: Nine patients underwent PEG with a modified introducer method under conscious sedation. A T-tube was attached to the channel of an endoscope connected to an automatic surgical insufflator. The stomach was inflated under the SPACE system. The intragastric pressure was kept between 4-8 mmH g with a flow of CO_2 at 35 L/min. Median procedure time, intragastric pressure, median systolic blood pressure, partial pressure of CO_2, abdominal girth before and immediately after PEG, and free gas and small intestinal gas on abdominal X-ray before and after PEG were recorded. RESULTS: PEG was completed under stable pneumostomach in all patients, with a median procedural time of 22 min. Median intragastric pressure was 6.9 mmH g and median arterial CO_2 pressure before and after PEG was 42.1 and 45.5 Torr(NS). The median abdominal girth before and after PEG was 68.1 and 69.6 cm(NS). A mild free gas image after PEG was observed in two patients, and faint abdominal gas in the downstream bowel was documented in two patients.CONCLUSION: SPACE might enable standardized pneumostomach and modified introducer procedure of PEG. 展开更多
关键词 PERCUTANEOUS endoscopic GASTROSTOMY Steadypressure automaticALLY controlled ENDOSCOPY CARBONDIOXIDE
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Optimal tracking control for automatic transmission shift process 被引量:2
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作者 万国强 李克强 +2 位作者 裴玲 黄英 张付军 《Journal of Beijing Institute of Technology》 EI CAS 2015年第4期458-465,共8页
In order to improve the shift quality, a linear quadratic optimal tracking control algorithm for automatic transmission shift process is proposed. The dynamic equations of the shift process are derived using a Lagrang... In order to improve the shift quality, a linear quadratic optimal tracking control algorithm for automatic transmission shift process is proposed. The dynamic equations of the shift process are derived using a Lagrange method. And a powertrain model is built in the Matlab/Simulink and veri- fied by the measurements. Considering the shift jerk and friction loss during the shift process, the tracking trajectories of the turbine speed and output shaft speed are defined. Furthermore, the linear quadratic optimal tracking control performance index is proposed. Based on the Pontryagin' s mini- mum principle, the optimal control law of the shift process is presented. Finally, the simulation study of the 1 - 2 upshift process under different load conditions is carried out with the powertrain model. The simulation results demonstrate that the shift jerk and friction loss can be significantly re- duced by applying the proposed optimal tracking control method. 展开更多
关键词 POWERTRAIN automatic transmission shift process optimal tracking control
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