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Achieving structurally stable O3-type layered oxide cathodes through site-specific cation-anion co-substitution for sodium-ion batteries
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作者 Yihao Shen Chen Cheng +5 位作者 Xiao Xia Lei Wang Xi Zhou Pan Zeng Jianrong Zeng Liang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期411-418,I0011,共9页
O3-type layered oxides have garnered great attention as cathode materials for sodium-ion batteries because of their abundant reserves and high theoretical capacity.However,challenges persist in the form of uncontrolla... O3-type layered oxides have garnered great attention as cathode materials for sodium-ion batteries because of their abundant reserves and high theoretical capacity.However,challenges persist in the form of uncontrollable phase transitions and intricate Na^(+)diffusion pathways during cycling,resulting in compromised structural stability and reduced capacity over cycles.This study introduces a special approach employing site-specific Ca/F co-substitution within the layered structure of O_(3)-NaNi_(0.5)Mn_(0.5)O_(2) to effectively address these issues.Herein,the strategically site-specific doping of Ca into Na sites and F into O sites not only expands the Na^(+)diffusion pathways but also orchestrates a mild phase transition by suppressing the Na^(+)/vacancy ordering and providing strong metal-oxygen bonding strength,respectively.The as-synthesized Na_(0.95)Ca_(0.05)Ni_(0.5)Mn_(0.5)O_(1.95)F_(0.05)(NNMO-CaF)exhibits a mild O3→O3+O'3→P3 phase transition with minimized interlayer distance variation,leading to enhanced structural integrity and stability over extended cycles.As a result,NNMO-CaF delivers a high specific capacity of 119.5 mA h g^(-1)at a current density of 120 mA g^(-1)with a capacity retention of 87.1%after 100 cycles.This study presents a promising strategy to mitigate the challenges posed by multiple phase transitions and augment Na^(+)diffusion kinetics,thus paving the way for high-performance layered cathode materials in sodium-ion batteries. 展开更多
关键词 Sodium-ion batteries O3-type layered oxides Site-specific co-doping Phase transition
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Feedback linearization and equivalent-disturbance compensation control strategy for piezoelectric stage
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作者 Tao Huang Yingbin Wang +3 位作者 Zhihong Luo Huajun Cao Guibao Tao Mingxiang Ling 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期49-59,共11页
Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,respectively.These systems have high positioning accuracy and high-frequency responses,and they are widely used ... Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,respectively.These systems have high positioning accuracy and high-frequency responses,and they are widely used in various precision/ultra-precision positioning fields.However,the main challenge with these devices is the inherent hysteresis nonlinearity of piezoelectric actuators,which seriously affects the tracking accuracy of a piezoelectric stage.Inspired by this challenge,in this work,we developed a Hammerstein model to describe the hysteresis nonlinearity of a piezoelectric stage.In particular,in our proposed scheme,a feedback-linearization algorithm is used to eliminate the static hysteresis nonlinearity.In addition,a composite controller based on equivalent-disturbance compensation was designed to counteract model uncertainties and external disturbances.An analysis of the stability of a closed-loop system based on this feedback-linearization algorithm and composite controller was performed,and this was followed by extensive comparative experiments using a piezoelectric stage developed in the laboratory.The experimental results confirmed that the feedback-linearization algorithm and the composite controller offer improved linearization and trajectory-tracking performance. 展开更多
关键词 Piezoelectric stage Hysteresis nonlinearity Feedback linearization Equivalent-disturbance compensation
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Designing ultrastable P2/O3-type layered oxides for sodium ion batteries by regulating Na distribution and oxygen redox chemistry
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作者 Jieyou Huang Weiliang Li +3 位作者 Debin Ye Lin Xu Wenwei Wu Xuehang Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期466-476,共11页
P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phas... P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phases remains a necessity.Herein,we design a P2/O3-type Na_(0.76)Ni_(0.31)Zn_(0.07)Mn_(0.50)Ti_(0.12)0_(2)(NNZMT)with high chemical/electrochemical stability by enhancing the coupling between the two phases.For the first time,a unique Na*extraction is observed from a Na-rich O3 phase by a Na-poor P2 phase and systematically investigated.This process is facilitated by Zn^(2+)/Ti^(4+)dual doping and calcination condition regulation,allowing a higher Na*content in the P2 phase with larger Na^(+)transport channels and enhancing Na transport kinetics.Because of reduced Na^(+)in the O3 phase,which increases the difficulty of H^(+)/Na^(+) exchange,the hydrostability of the O3 phase in NNZMT is considerably improved.Furthermore,Zn^(2+)/Ti^(4+)presence in NNZMT synergistically regulates oxygen redox chemistry,which effectively suppresses O_(2)/CO_(2) gas release and electrolyte decomposition,and completely inhibits phase transitions above 4.0 V.As a result,NNZMT achieves a high discharge capacity of 144.8 mA h g^(-1) with a median voltage of 3.42 V at 20 mA g^(-1) and exhibits excellent cycling performance with a capacity retention of 77.3% for 1000 cycles at 2000 mA g^(-1).This study provides an effective strategy and new insights into the design of high-performance layered-oxide cathode materials with enhanced structure/interface stability forSIBs. 展开更多
关键词 Sodium-ion batteries P2/O3-type layered oxides Na distribution Oxygen redox chemistry Hydrostability
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Tailoring-compensated ferrimagnetic state and anomalous Hall effect in quaternary Mn–Ru–V–Ga Heusler compounds
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作者 梁瑾静 郗学奎 +1 位作者 王文洪 刘永昌 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期595-603,共9页
Cubic Mn_(2)Ru_(x)Ga Heusler compound is a typical example of compensated ferrimagnet with attractive potential for high-density,ultrafast,and low-power spintronic applications.In the form of epitaxial thin films,Mn_(... Cubic Mn_(2)Ru_(x)Ga Heusler compound is a typical example of compensated ferrimagnet with attractive potential for high-density,ultrafast,and low-power spintronic applications.In the form of epitaxial thin films,Mn_(2)Ru_(x)Ga exhibits high spin polarization and high tunability of compensation temperature by freely changing the Ru content x in a broad range(0.3<x<1.0).Herein Mn-Ru-Ga-based polycrystalline bulk buttons prepared by arc melting are systematically studied and it is found that in equilibrium bulk form,the cubic structure is unstable when x<0.75.To overcome this limitation,Mn-Ru-Ga is alloyed with a fourth element V.By adjusting the content of V in the By adjusting the content of V in the Mn_(2)Ru_(0.75)V_(y)Ga and Mn_(2.25-y)Ru_(0.75)V_(y)Ga quaternary systems the magnetic compensation temperature is tuned.Compensation is achieved near 300 K which is confirmed by both the magnetic measurement and anomalous Hall effect measurement.The analyses of the anomalous Hall effect scaling in quaternary Mn-Ru-V-Ga alloy reveal the dominant role of skew scattering,notably that contributed caused by the thermally excited phonons,in contrast to the dominant intrinsic mechanism found in many other 3d ferromagnets and Heusler compounds.It is further shown that the Ga antisites and V content can simultaneously control the residual resistivity ratio(RRR)as well as the relative contribution of phonon and defect to the anomalous Hall effect a"/a0'in Mn-Ru-V-Ga,resulting in a scaling relation a"/a0'∝RRR^(1.8). 展开更多
关键词 compensated ferrimagnet anomalous Hall effect residual resistivity ratio
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Ultrahigh spatiotemporal resolution beam signal reconstruction with bunch phase compensation
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作者 You-Ming Deng Yong-Bin Leng +2 位作者 Xing-Yi Xu Jian Chen Yi-Mei Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期99-108,共10页
Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle accelerator.It is important to obtain time-domain waveforms of these signals with high temporal re... Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle accelerator.It is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter measurements.Therefore,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this paper.Compared with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed signal.The basic principles of the method,simulation,and experimental comparison are also introduced.Based on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal oscillation.The results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed. 展开更多
关键词 Turn-by-turn bunch phase compensation technique Equivalent sampling Signal reconstruction algorithm Ultrahigh spatiotemporal resolution SSRF
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Excavation compensation and bolt support for a deep mine drift
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作者 Longji Guo Zhigang Tao +1 位作者 Manchao He Massimo Coli 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3206-3220,共15页
To overcome large deformation of deep phosphate rock roadways and pillar damage,a new type of constant-resistance large-deformation negative Poisson’s ratio(NPR)bolt that can withstand a high prestress of at least 13... To overcome large deformation of deep phosphate rock roadways and pillar damage,a new type of constant-resistance large-deformation negative Poisson’s ratio(NPR)bolt that can withstand a high prestress of at least 130 KN was developed.In the conducted tests,the amount of deformation was 200-2000 mm,the breaking force reached 350 KN,and a high constant-resistance pre-stress was maintained during the deformation process.A stress compensation theory of phosphate rock excavation based on NPR bolts is proposed together with a balance system for bolt compensation of the time-space effect and high NPR pre-stress.Traditional split-set rock bolts are unable to maintain the stability of roadway roofs and pillars.To verify the support effect of the proposed bolt,field tests were conducted using both the proposed NPR bolts and split-set rock bolts as support systems on the same mining face.In addition,the stress compensation mechanism of roadway mining was simulated using the particle flow code in three dimensions(PFC^(3D))-fast Lagrangian analysis of continua(FLAC^(3D))particle-flow coupling numerical model.On-site monitoring and numerical simulations showed that the NPR excavation compensation support scheme effectively improves the stress state of the bolts and reduces the deformation of the surrounding rock.Compared to the original support scheme,the final deformation of the surrounding rock was reduced by approximately 70%.These results significantly contribute to domestic and foreign research on phosphate-rock NPR compensation support technology,theoretical systems,and engineering practices,and further promote technological innovation in the phosphate rock mining industry. 展开更多
关键词 Deep phosphate rock NPR bolt Split-set rock bolt PFC3D-FLAC3D compensation support
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Research on Anti-Fluctuation Control of Winding Tension System Based on Feedforward Compensation
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作者 Yujie Duan Jianguo Liang +4 位作者 Jianglin Liu Haifeng Gao Yinhui Li Jinzhu Zhang Xinyu Wen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1239-1261,共23页
In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tens... In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tension output,this paper proposed a tension fluctuation rejection strategy based on feedforward compensation.In addition to the bias harmonic curve of the unknown state,the tension fluctuation also contains the influence of bounded noise.A tension fluctuation observer(TFO)is designed to cancel the uncertain periodic signal,in which the frequency generator is used to estimate the critical parameter information.Then,the fluctuation signal is reconstructed by a third-order auxiliary filter.The estimated signal feedforward compensates for the actual tension fluctuation.Furthermore,a time-varying parameters fractional-order PID controller(TPFOPID)is realized to attenuate the bounded noise in the fluctuation.Finally,TPFOPID is enhanced by TFO and applied to control a tension control system considering multi-source disturbances.The stability of the method is analyzed by using the Lyapunov theorem.Finally,numerical simulations verify that the proposed scheme improves the tracking ability and robustness of the system in response to tension fluctuations. 展开更多
关键词 Constant tension control anti-fluctuation strategy tension fluctuation observer time-varying parameters fractional-order PID controller feedforward compensate
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The Rights to Claim for Industrial Injury Compensation and Tort Compensation are Applicable to the Law:Taking Fu and Li v.a Passenger Transport Company as an Example
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作者 Li Guo 《Journal of Contemporary Educational Research》 2024年第1期154-158,共5页
In the case of third-party tort,due to the lack of clear and detailed provisions on the treatment of employee’s industrial injury insurance payment and tort damage compensation,the judicial theory and practice have b... In the case of third-party tort,due to the lack of clear and detailed provisions on the treatment of employee’s industrial injury insurance payment and tort damage compensation,the judicial theory and practice have brought many disputes.Through combing the current relevant laws and regulations,it can be found that the application of the two systems will lead to the overlapping of industrial injury compensation.This paper analyzes the problems arising from the concurrence of industrial injury compensation and tort compensation using the case of Fu and Li v.a passenger transport company,and puts forward some ideas and suggestions on how to improve the settlement measures of such cases. 展开更多
关键词 Industrial injury compensation and tort compensation Double indemnity
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Problems and Countermeasures to Improve Clinical Trial Participants’Compensation Rights in China
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作者 Yang Xiuqiao Wen Ping +2 位作者 Lin Hong Chen Wenhuan Chen Yuwen 《Asian Journal of Social Pharmacy》 2024年第1期58-63,共6页
Objective To discuss the problems existing in the compensation of Chinese clinical trial participants and propose some suggestions for improving their rights.Methods The literature related to the participants’right t... Objective To discuss the problems existing in the compensation of Chinese clinical trial participants and propose some suggestions for improving their rights.Methods The literature related to the participants’right to compensation at home and abroad was searched to study the inadequacy of the compensation right for clinical trial participants in China from four aspects:insurance system,principle of attribution,legal relationship and compensation regulations.Then,some suggestions to improve the participants’right to compensation were proposed.Results and Conclusion China lacks clear legal norms for participants’right to compensation.There are problems such as unclear insurance rules and compensation rules,unclear contractual relationships between parties to clinical trials,and no laws and regulations to rely on for attribution and compensation.China should issue regulatory guidelines related to the right to compensation of participants in clinical trials,so that all parties in clinical trials can have rules to follow if there is the occurrence of injury,which can better protect the rights and interests of the participants. 展开更多
关键词 clinical trial PARTICIPANT compensation right
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The Translation of Chinese Literature under the Theory of Translation Compensation
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作者 WANG Rong 《Philosophy Study》 2024年第1期9-15,共7页
In order to promote the exchange of Chinese culture with foreign countries,translators bear an important mission in the process of cross-cultural communication.Although there are cultural differences,we can achieve cu... In order to promote the exchange of Chinese culture with foreign countries,translators bear an important mission in the process of cross-cultural communication.Although there are cultural differences,we can achieve cultural dissemination and exchange through continuous cultural dialogue.As an important way for foreign scholars to understand the history of the Shang and Zhou Dynasties in China,the translation of historical texts is crucial.Multiple typical cases are selected under the guidance of the translation theory of compensation to use relevant methods or techniques from the three levels of language,culture,and aesthetics to compensate for the loss of Li Xueqin’s The Origin of Ancient Chinese Civilization in English translation proofreading. 展开更多
关键词 translation compensation theory Li Xueqin The Origin of Ancient Chinese Civilization
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Salvia Polyphenolates Combined with Doxophylline in the Treatment of Patients with Chronic Pulmonary Heart Disease in the Compensated Stage
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作者 Meijuan Ma Fen Yang 《Journal of Clinical and Nursing Research》 2024年第5期52-55,共4页
Objective:To statistically determine the effect of salvia polyphenolates combined with doxophylline treatment in patients with chronic pulmonary heart disease in the compensated stage.Methods:From January 2023 to Janu... Objective:To statistically determine the effect of salvia polyphenolates combined with doxophylline treatment in patients with chronic pulmonary heart disease in the compensated stage.Methods:From January 2023 to January 2024,76 patients with chronic pulmonary heart disease in the compensated stage were selected as research subjects.The patients were divided into a research group and a reference group using a randomized numerical table method.The research group was treated with salvia polyphenolates combined with doxophylline,while the reference group received conventional therapy.The treatment effects of the two groups were compared.Results:The patients in the research group,treated with salvia polyphenolates combined with doxophylline,showed maximal ventilation of 73.26±4.83 L/min,left ventricular ejection fraction of 56.14±1.98%,and total effective treatment rate of 94.74%.These results were better than those of the reference group.The differences between the data of the research group and the reference group were statistically significant(P<0.05).Conclusion:For patients with chronic pulmonary heart disease in the compensated stage,treatment with salvia polyphenolates combined with doxophylline significantly improves maximum ventilation and left ventricular ejection fraction,and also results in a higher total effective treatment rate. 展开更多
关键词 Salvia polyphenolates Doxophylline Chronic pulmonary heart disease in the compensated stage
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Design of Cold-Junction Compensation and Disconnection Detection Circuits of Various Thermocouples and Implementation of Multi-Channel Interfaces Using Them-A Secondary Publication
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作者 Hyeong-Woo Cha 《Journal of Electronic Research and Application》 2024年第1期93-105,共13页
Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC... Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain. 展开更多
关键词 R-type thermocouple(TC) Cold-junction compensation(CJC) TC disconnection detection Multi-channel interface circuit Sensor interface
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ADAPTIVE FEED-FORWARD COMPENSATOR FOR HARMONIC CANCELLATION IN ELECTRO-HYDRAULIC SERVO SYSTEM 被引量:3
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作者 YAO Jianjun WANG Liquan +2 位作者 JIANG Hongzhou WU Zhenshun HAN Junwei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第1期77-81,共5页
Since the dead zone phenomenon occurs in electro-hydraulic servo system, the output of the system corresponding to a sinusoidal input contains higher harmonic besides the fundamental input, which causes harmonic disto... Since the dead zone phenomenon occurs in electro-hydraulic servo system, the output of the system corresponding to a sinusoidal input contains higher harmonic besides the fundamental input, which causes harmonic distortion of the output signal. The method for harmonic cancellation based on adaptive filter is proposed. The task is accomplished by generating reference signals with frequency that should be eliminated from the output. The reference inputs are weighted by the adaptive filter in such a way that it closely matches the harmonic. The output of the adaptive filter is a harmonic replica and is injected to the fundamental signal such that the output harmonic is cancelled leaving the desired signal alone, and the total harmonic distortion (THD) is greatly reduced. The weights of filter are adjusted on-line according to the control error by using least-mean-square (LMS) algorithm. Simulation results performed with a hydraulic system demonstrate the efficiency and validity of the proposed adaptive feed-forward compensator (AFC) control scheme 展开更多
关键词 Adaptive filter Adaptive feed-forward compensator Least-mean-square algorithm Dead zone Harmonic distortion
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A FUZZY UNCERTAINTY COMPENSATOR FOR MANIPULATOR TRAJECTORY TRACKING 被引量:1
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作者 ChenWuwei JamesKMills 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第1期17-20,共4页
A novel fuzzy logic compensating (FLC) scheme is proposed to enhance theconventional computed-torque control (CTC) structure of manipulators The control scheme is based onthe combination of a classical CTC and FLC, an... A novel fuzzy logic compensating (FLC) scheme is proposed to enhance theconventional computed-torque control (CTC) structure of manipulators The control scheme is based onthe combination of a classical CTC and FLC, and the resulting control scheme has a simple structurewith improved robustness. Further improvement of the performance of the FLC scheme is achievedthrough automatic tuning of a weight parameter a leading to a self-tuning fuzzy logic compensator,so the system uncertainty can be compensated very well. By taking into account the full nonlinearnature of the robotic dynamics, the overall closed-loop system is shown to be asymptotically stable.Experimental results demonstrate the effectiveness of the computed torque and fuzzy compensationscheme to control a manipulator during a trajectory tracking task. 展开更多
关键词 MANIPULATOR Trajectory tracking Fuzzy compensator
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Hybrid compensation method for traction power quality compensators in electrified railway power supply system 被引量:1
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作者 Mohammad Arabahmadi Mahdi Banejad Ali Dastfan 《Global Energy Interconnection》 CAS CSCD 2021年第2期158-168,共11页
In order to improve the Power Quality(PQ)of traction power supply system and reduce the power rating and operation cost of compensator,a Static VAR Compensator(SVC)integrated Railway Power Conditioner(RPC)is presented... In order to improve the Power Quality(PQ)of traction power supply system and reduce the power rating and operation cost of compensator,a Static VAR Compensator(SVC)integrated Railway Power Conditioner(RPC)is presented in this paper.RPC is a widely used device in the AC electrified railway systems to enhance the PQ indices of the main network.The next generation of this equipment is Active Power Quality Compensator(APQC).The major concern of these compensators is their high kVA rating.In this paper,a hybrid technique is proposed to solve aforementioned problems.A combination of SVC as an auxiliary device is employed together with the main compensators,i.e.,RPC and APQC that leads on to the reduction of power rating of the main compensators.The use of proposed scheme will cause to reduce significantly the initial investment cost of compensation system.The main compensators are only utilized to balance active powers of two adjacent feeder sections and suppress harmonic currents.The SVCs are used to compensate reactive power and suppress the third and fifth harmonic currents.In this paper firstly,the PQ compensation procedure in AC electrified railway is analyzed step by step.Then,the control strategies for SVC and the main compensators are presented.Finally,a simulation is fulfilled using Matlab/Simulink software to verify the effectiveness and validity of the proposed scheme and compensation strategy and also demonstrate that this technique could compensate all PQ problems. 展开更多
关键词 AC electrified railway Power quality compensation Auxiliary compensator Static var compensator Power rating reduction of converters
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A Delay-Dependent Anti-Windup Compensator for Wide-Area Power Systems With Time-Varying Delays and Actuator Saturation 被引量:2
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作者 Maddela Chinna Obaiah Bidyadhar Subudhi 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第1期106-117,共12页
In this paper, a delay-dependent anti-windup compensator is designed for wide-area power systems to enhance the damping of inter-area low-frequency oscillations in the presence of time-varying delays and actuator satu... In this paper, a delay-dependent anti-windup compensator is designed for wide-area power systems to enhance the damping of inter-area low-frequency oscillations in the presence of time-varying delays and actuator saturation using an indirect approach. In this approach, first, a conventional wide-area damping controller is designed by using output feedback with regional pole placement approach without considering time-varying delays and actuator saturation. Then to mitigate the effect of both time-varying delays and actuator saturation, an add-on delay-dependent anti-windup compensator is designed. Based on generalized sector conditions, less conservative delay-dependent sufficient conditions are derived in the form of a linear matrix inequality(LMI) to guarantee the asymptotic stability of the closedloop system in the presence of time-varying delays and actuator saturation by using Lyapunov-Krasovskii functional and Jensen integral inequality. Based on sufficient conditions, the LMI-based optimization problem is formulated and solved to obtain the compensator gain which maximizes the estimation of the region of attraction and minimizes the upper bound of-gain. Nonlinear simulations are performed first using MATLAB/Simulink on a two-area four-machine power system to evaluate the performance of the proposed controller for two operating conditions, e.g.,3-phase to ground fault and generator 1 terminal voltage variation. Then the proposed controller is implemented in real-time on an OPAL-RT digital simulator. From the results obtained it is verified that the proposed controller provides sufficient damping to the inter-area oscillations in the presence of time-varying delays and actuator saturation and maximizes the estimation of the region of attraction. 展开更多
关键词 Index Terms—Anti-windup compensator actuator saturation FACTS devices H∞controller inter-area oscillations LMI time delay.
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A THEORETICAL ANALYSIS OF WORKING CHARACTER OF WEFT TENSION COMPENSATOR IN NEEDLE LOOMS
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作者 江志安 《Journal of China Textile University(English Edition)》 EI CAS 1995年第1期36-42,共7页
Based on the analysis, according to the principle of vibration, of the working character of weft tension compensator in needle looms, the paper studied the principle of tension compensation and introduced the idea of ... Based on the analysis, according to the principle of vibration, of the working character of weft tension compensator in needle looms, the paper studied the principle of tension compensation and introduced the idea of compensating coefficient. The paper also discussed some factors affecting the effect of tension compensation. 展开更多
关键词 NEEDLE looms WEFT tension tension compensation tension compensator working CHARACTER compensating coefficient.
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Improvement of machining accuracy in precision micro boring system by forecasting compensatory control technique
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作者 高栋 袁哲俊 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第1期11-15,共5页
Presents the design of a micro boring servo system. A piezoelectric actuator is employed to compensate the deflection errors of the cutter in the radial direction to reduce the force induced errors in the workpiece. I... Presents the design of a micro boring servo system. A piezoelectric actuator is employed to compensate the deflection errors of the cutter in the radial direction to reduce the force induced errors in the workpiece. In order to bore small and deep holes, the boring bar is designed with a new structure consisting of two concentric bars, one being used for error measuring and the other for error compensation. As a result, the size of the micro boring bar is not affected even after the piezoelectric actuator and strain gauges have been incorporated. The outer diameter of the boring bar used is 16 mm and the length to diameter ratio is greater than 9. A Forecasting Compensatory Control (FCC) technique is adopted in this system for error prediction and error compensation. The off line forecasting compensatory control simulation and on line cutting results have verified that the roundness form errors in the workpiece can be reduced up to 60 percent with the developed micro boring servo system. 展开更多
关键词 MICRO BORING BAR on line ERROR compensATION
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Validation of the albumin-bilirubin score for identifying decompensation risk in patients with compensated cirrhosis 被引量:3
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作者 Huttakan Navadurong Kessarin Thanapirom +4 位作者 Salisa Wejnaruemarn Thaninee Prasoppokakorn Roongruedee Chaiteerakij Piyawat Komolmit Sombat Treeprasertsuk 《World Journal of Gastroenterology》 SCIE CAS 2023年第32期4873-4882,共10页
BACKGROUND The albumin-bilirubin(ALBI)score is an index of liver function recently developed to assess prognosis in patients with hepatocellular carcinoma(HCC).It can detect small changes in liver dysfunction and has ... BACKGROUND The albumin-bilirubin(ALBI)score is an index of liver function recently developed to assess prognosis in patients with hepatocellular carcinoma(HCC).It can detect small changes in liver dysfunction and has been successfully applied to the prediction of survival in patients with non-malignant liver diseases of various etiologies.AIM To investigate the ALBI score for identifying decompensation risk at the 3-year follow-up in patients with compensated cirrhosis.METHODS One-hundred and twenty-three patients with compensated cirrhosis without HCC in King Chulalongkorn Memorial Hospital diagnosed by imaging were retrospectively enrolled from January 2016 to December 2020.A total of 113 patients(91.9%)had Child A cirrhosis with a median model for end-stage liver disease(MELD)score of less than 9.Baseline clinical and laboratory variables and decompensation events were collected.The ALBI score was calculated and validated to classify decompensation risk into low-,middle-,and high-risk groups using three ALBI grade ranges(ALBI grade 1:≤-2.60;grade 2:>-2.60 but≤-1.39;grade 3:>-1.39).Decompensation events were defined as ascites development,variceal bleeding,or grade 3 or 4 hepatic encephalopathy.RESULTS Among 123 cirrhotic patients enrolled,13.8%(n=17)developed decompensating events at a median time of 25[95%confidence interval(CI):17-31]mo.Median baseline ALBI score in compensated cirrhosis was significantly lower than that of patients who developed decompensation events[-2.768(-2.956 to-2.453)vs-2.007(-2.533 to-1.537);P=0.01].Analysis of decompensation risk at 3 years showed that ALBI score had a time-dependent area under the curve(tAUC)of 0.86(95%CI:0.78-0.92),which was significantly better than that of ALBI-Fibrosis-4(ALBI-FIB4)score(tAUC=0.77),MELD score(tAUC=0.66),Child-Pugh score(tAUC=0.65),and FIB-4 score(tAUC=0.48)(P<0.05 for all).The 3-year cumulative incidence of decompensation was 3.1%,22.6%,and 50%in the low-,middle-,and high-risk groups,respectively(P<0.001).The odds ratio for decompensation in patients of the high-risk group was 23.33(95%CI:3.88-140.12,P=0.001).CONCLUSION The ALBI score accurately identifies decompensation risk at the 3-year follow-up in patients with compensated cirrhosis.Those cirrhotic patients with a high-risk grade of ALBI score showed a 23 times greater odds of decompensation. 展开更多
关键词 Albumin-bilirubin score compensated cirrhosis Hepatic decompensation risk
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Eigenstructure assignment of lower-order dynamical compensatorsfor linear systems with unknown inputs
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作者 郭奔 王明彦 张福恩 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第3期53-57,共5页
Presents a systematic design method of reduced order dynamical compensator via the parametric representations of eigenstructure assignment for linear system, which provides maximum degree of freedom, and can be easily... Presents a systematic design method of reduced order dynamical compensator via the parametric representations of eigenstructure assignment for linear system, which provides maximum degree of freedom, and can be easily used for the design of a linear system with unknown inputs under some conditions. Even when these conditions are not satisfied, the lower order dynamical compensator can also be designed under some relaxed conditions. Some examples illustrate that the method is neat, simple and effective. 展开更多
关键词 DYNAMICAL compensator eigenstructure ASSIGNMENT linear system unknown INPUTS
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