Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.816532
M. Yoshida, K. Ogura, H. Iwamoto, E. Hiraki, M. Nakaoka
This paper describes a three-phase voltage source-fed soft switching inverter system with auxiliary resonant AC link snubbers for CVCF application which incorporates by the optimal type-1 servo controller operated on the d-q coordinate frame. In this paper, the steady state and transient-state operating performance of this soft switching inverter and is illustrated and evaluated on the basis of its computer simulation analysis. The circuit design procedure of an active resonant snubber circuit topology on the AC side is illustrated by the simulation results. The effectiveness of this soft switching inverter is proved from a practical point of view.
{"title":"Performance evaluations of three-phase voltage source instantaneous voltage vector modulated soft commutation inverter with active resonant snubbers in three-phase AC load side","authors":"M. Yoshida, K. Ogura, H. Iwamoto, E. Hiraki, M. Nakaoka","doi":"10.1109/IECON.1999.816532","DOIUrl":"https://doi.org/10.1109/IECON.1999.816532","url":null,"abstract":"This paper describes a three-phase voltage source-fed soft switching inverter system with auxiliary resonant AC link snubbers for CVCF application which incorporates by the optimal type-1 servo controller operated on the d-q coordinate frame. In this paper, the steady state and transient-state operating performance of this soft switching inverter and is illustrated and evaluated on the basis of its computer simulation analysis. The circuit design procedure of an active resonant snubber circuit topology on the AC side is illustrated by the simulation results. The effectiveness of this soft switching inverter is proved from a practical point of view.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114485251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.822169
L. Berger, J. W. Mrosk, C. Ettl, H. Fecht, S. Flege, H. Hahn, U. Wolff
Amorphous metal alloys are ideally suited for interconnects in micro-electromechanical systems (MEMS) because of their resistance against migration and diffusion, and their stability in chemically aggressive environments, which should both lead to a substantial improvement of lifetime and reliability of robust sensors. Amorphous aluminium alloy metallizations are especially promising for surface acoustic wave (SAW) sensors, where the interconnects are exposed to considerable mechanical strains. In this work, first experimental results for amorphous 400 nm Al/sub 84/Cu/sub 4/Y/sub 12/ alloy thin films deposited on single crystal LiTaO/sub 3/ piezoelectric substrates at room temperature (R.T.) by ultra-high vacuum (UHV) electron beam evaporation will be presented. The composition of the films was validated by Rutherford backscattering (RBS) spectroscopy, and their amorphous structure was confirmed by X-ray diffraction (XRD) analysis. The roughness and hardness of the metallization, both important parameters for wire bonding, were investigated by scanning probe microscopy (SPM) and depth-sensing nanoindentation. The electrical resistivity was determined by four-point probe measurements. The amorphous films were annealed in UHV, and their crystallization temperature T/sub x/ was investigated by XRD.
{"title":"Properties of amorphous AlCuY alloy metallizations","authors":"L. Berger, J. W. Mrosk, C. Ettl, H. Fecht, S. Flege, H. Hahn, U. Wolff","doi":"10.1109/IECON.1999.822169","DOIUrl":"https://doi.org/10.1109/IECON.1999.822169","url":null,"abstract":"Amorphous metal alloys are ideally suited for interconnects in micro-electromechanical systems (MEMS) because of their resistance against migration and diffusion, and their stability in chemically aggressive environments, which should both lead to a substantial improvement of lifetime and reliability of robust sensors. Amorphous aluminium alloy metallizations are especially promising for surface acoustic wave (SAW) sensors, where the interconnects are exposed to considerable mechanical strains. In this work, first experimental results for amorphous 400 nm Al/sub 84/Cu/sub 4/Y/sub 12/ alloy thin films deposited on single crystal LiTaO/sub 3/ piezoelectric substrates at room temperature (R.T.) by ultra-high vacuum (UHV) electron beam evaporation will be presented. The composition of the films was validated by Rutherford backscattering (RBS) spectroscopy, and their amorphous structure was confirmed by X-ray diffraction (XRD) analysis. The roughness and hardness of the metallization, both important parameters for wire bonding, were investigated by scanning probe microscopy (SPM) and depth-sensing nanoindentation. The electrical resistivity was determined by four-point probe measurements. The amorphous films were annealed in UHV, and their crystallization temperature T/sub x/ was investigated by XRD.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116892062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.816531
H. Yamamoto, E. Hiraki, Y. Konishi, K. Nishida, T. Horiuchi, Y. Sugawara, M. Nakaoka
In this paper, a prototype of a multi-functional controlled three-phase voltage-source bidirectional zero voltage soft-switching PWM converter with three auxiliary active resonant commutated snubber link (ARCS) is presented for battery and/or electric double layer capacitor energy storage system (BESS). The operating principle of this active resonant snubber-assisted soft-switching converter circuit for BESS and multi-functional digital control-based converter system including active rectifier and inverter operation modes are described. Operation characteristics of this bidirectional three phase soft-switching space voltage vector modulated converter with ARCS for BESS is demonstrated under the conditions of battery discharging-based peak-cut mode and battery charging-based energy storage mode in with conventional utility three phase hard-switching converter for BESS. The effectiveness of the converter system is proved on the basis of simulation analysis.
{"title":"Utility-interactive three-phase soft-switching pulse width modulated converter with active resonant snubbers in bridge leg sides for energy storage devices","authors":"H. Yamamoto, E. Hiraki, Y. Konishi, K. Nishida, T. Horiuchi, Y. Sugawara, M. Nakaoka","doi":"10.1109/IECON.1999.816531","DOIUrl":"https://doi.org/10.1109/IECON.1999.816531","url":null,"abstract":"In this paper, a prototype of a multi-functional controlled three-phase voltage-source bidirectional zero voltage soft-switching PWM converter with three auxiliary active resonant commutated snubber link (ARCS) is presented for battery and/or electric double layer capacitor energy storage system (BESS). The operating principle of this active resonant snubber-assisted soft-switching converter circuit for BESS and multi-functional digital control-based converter system including active rectifier and inverter operation modes are described. Operation characteristics of this bidirectional three phase soft-switching space voltage vector modulated converter with ARCS for BESS is demonstrated under the conditions of battery discharging-based peak-cut mode and battery charging-based energy storage mode in with conventional utility three phase hard-switching converter for BESS. The effectiveness of the converter system is proved on the basis of simulation analysis.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116286861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.819381
K. Gopalan, S. Wenndt, E. J. Cupples
An analysis of speech under stress using its amplitude and frequency modulation (AM and FM) characteristics has been carried out. From the preliminary results using actual stressed speech from an operational aviation emergency, stress, in general, appears to increase the modulation behavior in both AM and FM. In particular, the modulation characteristics become significantly more if the analysis (carrier) frequency is centered at one of the resonant frequencies of the vocal tract. Moreover, the spectra of AM envelopes show increasing peak frequencies with stress. The highest peak in the spectra of the demodulated instantaneous frequency and the AM envelope appear to track the fundamental frequency F0. Linear prediction model of the AM envelope also shows a peak at F0 regardless of the analysis (center) frequency; the peak does not be distinct at all center frequencies, however.
{"title":"An analysis of speech under stress using certain modulation features","authors":"K. Gopalan, S. Wenndt, E. J. Cupples","doi":"10.1109/IECON.1999.819381","DOIUrl":"https://doi.org/10.1109/IECON.1999.819381","url":null,"abstract":"An analysis of speech under stress using its amplitude and frequency modulation (AM and FM) characteristics has been carried out. From the preliminary results using actual stressed speech from an operational aviation emergency, stress, in general, appears to increase the modulation behavior in both AM and FM. In particular, the modulation characteristics become significantly more if the analysis (carrier) frequency is centered at one of the resonant frequencies of the vocal tract. Moreover, the spectra of AM envelopes show increasing peak frequencies with stress. The highest peak in the spectra of the demodulated instantaneous frequency and the AM envelope appear to track the fundamental frequency F0. Linear prediction model of the AM envelope also shows a peak at F0 regardless of the analysis (center) frequency; the peak does not be distinct at all center frequencies, however.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123443405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.816503
J. Jin, J. Allan, K. Payne
This paper describes the application of neural networks in earth fault detection and location on a fourth rail DC railway power supply system. A multi-layer perceptron (MLP) network is used with the Leventberg-Marquardt algorithm as the training algorithm. The neural network based fault detector uses 600 Hz harmonic values of voltages and currents at the DC side of rectifiers as the inputs of the neural network. To get the training and testing data, simulations have been conducted to address different complex fault situations. Results show that the neural network based fault detector is fast and accurate. Further work, including more field tests to build on earlier limited tests, will be carried out to investigate the implementation of the neural network based detector for the fourth rail system in real life.
{"title":"Neural network based earth fault detection and location on a fourth rail DC railway","authors":"J. Jin, J. Allan, K. Payne","doi":"10.1109/IECON.1999.816503","DOIUrl":"https://doi.org/10.1109/IECON.1999.816503","url":null,"abstract":"This paper describes the application of neural networks in earth fault detection and location on a fourth rail DC railway power supply system. A multi-layer perceptron (MLP) network is used with the Leventberg-Marquardt algorithm as the training algorithm. The neural network based fault detector uses 600 Hz harmonic values of voltages and currents at the DC side of rectifiers as the inputs of the neural network. To get the training and testing data, simulations have been conducted to address different complex fault situations. Results show that the neural network based fault detector is fast and accurate. Further work, including more field tests to build on earlier limited tests, will be carried out to investigate the implementation of the neural network based detector for the fourth rail system in real life.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122015438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.816459
J.F.M. de Almeida, L. Valdenebro, E. Bin
In the present paper, a fuzzy logic based maximum torque control is proposed for a single-phase induction motor (SPIM) with a controlled capacitor. The objective of the control algorithm is to find the capacitor value related to the maximum torque for any rotor speed value during the starting period. The fuzzy logic-based method has the advantage that adaptively changes the step size of the control variable and in this manner fast convergence is achieved. The complete control system has been developed and validated by simulation results.
{"title":"Fuzzy logic based maximum torque control for a single-phase induction motor","authors":"J.F.M. de Almeida, L. Valdenebro, E. Bin","doi":"10.1109/IECON.1999.816459","DOIUrl":"https://doi.org/10.1109/IECON.1999.816459","url":null,"abstract":"In the present paper, a fuzzy logic based maximum torque control is proposed for a single-phase induction motor (SPIM) with a controlled capacitor. The objective of the control algorithm is to find the capacitor value related to the maximum torque for any rotor speed value during the starting period. The fuzzy logic-based method has the advantage that adaptively changes the step size of the control variable and in this manner fast convergence is achieved. The complete control system has been developed and validated by simulation results.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124624009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.822202
Jun-Keun Ji, S. Sul
In this paper, a predictive current control scheme for a twelve-pulse parallel connected dual power converter system without interphase reactors (IPR) is presented. Firstly, the characteristics of system without IPR are analyzed and compared with that of system with IPR. And the predictive current control of this system is discussed. Finally the validity of the presented system and the excellence of the predictive current control response is proved through the simulation results and experimental results.
{"title":"Operation analysis and new current control of parallel connected dual converter system without interphase reactors","authors":"Jun-Keun Ji, S. Sul","doi":"10.1109/IECON.1999.822202","DOIUrl":"https://doi.org/10.1109/IECON.1999.822202","url":null,"abstract":"In this paper, a predictive current control scheme for a twelve-pulse parallel connected dual power converter system without interphase reactors (IPR) is presented. Firstly, the characteristics of system without IPR are analyzed and compared with that of system with IPR. And the predictive current control of this system is discussed. Finally the validity of the presented system and the excellence of the predictive current control response is proved through the simulation results and experimental results.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124715410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.816547
M. Zhang, A. Nagamatsu
In this article, a new control method for rotational motion control of a flexible arm by using an LQN control system is proposed. This control system is based on combining discrete-time state feedback control by linear quadratic optimal control theory with neuro-adaptive feedforward control by a neural network model. While the discrete-time state feedback control loop provides the elastic vibration control, the neuro-adaptive feedforward control loop controls the endpoint position. Numerical simulation is carried out for a single flexible arm by employing the proposed LQN control system. From the simulation results, it is confirmed that the elastic vibration in positioning control is effectively suppressed, and control error of the endpoint position decreases gradually with the passing of time, and in steady-state, the control error becomes almost zero. Consequently, desired endpoint motion is achieved, showing the effectiveness of the proposed control method by use of the LQN control system.
{"title":"Motion control of flexible arm by using neuro-adaptive control: LQN control system and numerical simulation","authors":"M. Zhang, A. Nagamatsu","doi":"10.1109/IECON.1999.816547","DOIUrl":"https://doi.org/10.1109/IECON.1999.816547","url":null,"abstract":"In this article, a new control method for rotational motion control of a flexible arm by using an LQN control system is proposed. This control system is based on combining discrete-time state feedback control by linear quadratic optimal control theory with neuro-adaptive feedforward control by a neural network model. While the discrete-time state feedback control loop provides the elastic vibration control, the neuro-adaptive feedforward control loop controls the endpoint position. Numerical simulation is carried out for a single flexible arm by employing the proposed LQN control system. From the simulation results, it is confirmed that the elastic vibration in positioning control is effectively suppressed, and control error of the endpoint position decreases gradually with the passing of time, and in steady-state, the control error becomes almost zero. Consequently, desired endpoint motion is achieved, showing the effectiveness of the proposed control method by use of the LQN control system.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129851828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.819378
I. Wattar, W. Hafez, Z. Gao
This paper presents a model-based approach to online monitoring and fault diagnosis of rotating machinery. Fault (e.g., rub, imbalance) modes of rotating machines are classified using nonlinear dynamic models with quasi-periodic and chaotic behavior. The paper identifies a class of fault scenario under which the well-accepted nonlinear state filters (e.g., EKF) cannot be used to monitor or diagnose the machinery. An effective on-line model-based monitoring and diagnosis algorithm is proposed. The algorithm is based on computationally efficient algorithms for signal processing and parameter identification.
{"title":"Model-based diagnosis of chaotic vibration signals","authors":"I. Wattar, W. Hafez, Z. Gao","doi":"10.1109/IECON.1999.819378","DOIUrl":"https://doi.org/10.1109/IECON.1999.819378","url":null,"abstract":"This paper presents a model-based approach to online monitoring and fault diagnosis of rotating machinery. Fault (e.g., rub, imbalance) modes of rotating machines are classified using nonlinear dynamic models with quasi-periodic and chaotic behavior. The paper identifies a class of fault scenario under which the well-accepted nonlinear state filters (e.g., EKF) cannot be used to monitor or diagnose the machinery. An effective on-line model-based monitoring and diagnosis algorithm is proposed. The algorithm is based on computationally efficient algorithms for signal processing and parameter identification.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128313233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-11-29DOI: 10.1109/IECON.1999.819432
K. Tazi, E. Monmasson, J. Louis
Complex industrial applications use several AC machines. It is a necessity to centralize the control of all the machines in order to reduce the cost and to optimize the reliability and the efficiency of the control system. In this paper, the authors present an original architecture dedicated to the current vector control of a set of AC machines. It is exclusively based on FPGAs (field programmable gate arrays), and is, for this reason, fully reconfigurable. The whole algorithm is distributed in several dedicated elementary processors. Each one of them is implemented in an FPGA component. Thanks to pipelined operations, a very short global computing time has been obtained. With the actual system, the current components in a rotating frame of up to four AC machines can be controlled at a sampling rate of 20 kHz. Experimental results are also presented to validate the study.
{"title":"Description of an entirely reconfigurable architecture dedicated to the current vector control of a set of AC machines","authors":"K. Tazi, E. Monmasson, J. Louis","doi":"10.1109/IECON.1999.819432","DOIUrl":"https://doi.org/10.1109/IECON.1999.819432","url":null,"abstract":"Complex industrial applications use several AC machines. It is a necessity to centralize the control of all the machines in order to reduce the cost and to optimize the reliability and the efficiency of the control system. In this paper, the authors present an original architecture dedicated to the current vector control of a set of AC machines. It is exclusively based on FPGAs (field programmable gate arrays), and is, for this reason, fully reconfigurable. The whole algorithm is distributed in several dedicated elementary processors. Each one of them is implemented in an FPGA component. Thanks to pipelined operations, a very short global computing time has been obtained. With the actual system, the current components in a rotating frame of up to four AC machines can be controlled at a sampling rate of 20 kHz. Experimental results are also presented to validate the study.","PeriodicalId":378710,"journal":{"name":"IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128742287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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