Pub Date : 2003-06-09DOI: 10.1109/ISIE.2003.1267278
B. A. Welchko, J. Nagashima
The recent adoption of the 42 V powernet standard for the next generation of vehicles has focused substantial research effort into the design of electric machines for light hybrid vehicles. However, research investigating the merits of topology selection for this application has been sparse. This paper investigates the potential performance benefits, which could be realized by adopting a different inverter topology. This paper discusses the merits of delta-connected motors, bipolar inverters and cascaded inverters when compared to a standard inverter. The flexibility provided by adopting a non-standard topology can produce a better overall design when one or more of the design specifications are proving difficult to meet economically with the standard topology. As a particular design example, this paper shows that a cascaded inverter topology driving an open winding motor can increase the high-speed power density of an induction motor by 73%. For an interior permanent magnet motor, this paper shows that this topology can increase low speed torque by 9% and high-speed power by up to 300%.
{"title":"A comparative evaluation of motor drive topologies for low-voltage, high-power EV/HEV propulsion systems","authors":"B. A. Welchko, J. Nagashima","doi":"10.1109/ISIE.2003.1267278","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267278","url":null,"abstract":"The recent adoption of the 42 V powernet standard for the next generation of vehicles has focused substantial research effort into the design of electric machines for light hybrid vehicles. However, research investigating the merits of topology selection for this application has been sparse. This paper investigates the potential performance benefits, which could be realized by adopting a different inverter topology. This paper discusses the merits of delta-connected motors, bipolar inverters and cascaded inverters when compared to a standard inverter. The flexibility provided by adopting a non-standard topology can produce a better overall design when one or more of the design specifications are proving difficult to meet economically with the standard topology. As a particular design example, this paper shows that a cascaded inverter topology driving an open winding motor can increase the high-speed power density of an induction motor by 73%. For an interior permanent magnet motor, this paper shows that this topology can increase low speed torque by 9% and high-speed power by up to 300%.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124124128","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 : 2003-06-09DOI: 10.1109/ISIE.2003.1267900
G. Serra
This paper presents a fuzzy proportional-integral (PI) controller, which is a discrete-time version of a conventional PI controller. The data base as well as the constant PI control gains are optimized by using a genetic algorithm according to the following design specifications: minimizing the overshoot, the settling time and smoothing of the output curve. Thus, the optimization problem close to a multiobjective optimization one, resulting in an optimal fuzzy PI controller. Simulation results are shown to demonstrate the improvement over a conventional one.
{"title":"A multiobjective fuzzy PI controller based on genetic algorithm","authors":"G. Serra","doi":"10.1109/ISIE.2003.1267900","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267900","url":null,"abstract":"This paper presents a fuzzy proportional-integral (PI) controller, which is a discrete-time version of a conventional PI controller. The data base as well as the constant PI control gains are optimized by using a genetic algorithm according to the following design specifications: minimizing the overshoot, the settling time and smoothing of the output curve. Thus, the optimization problem close to a multiobjective optimization one, resulting in an optimal fuzzy PI controller. Simulation results are shown to demonstrate the improvement over a conventional one.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125632111","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 : 2003-06-09DOI: 10.1109/ISIE.2003.1267249
M. Freitas, J. Afonso, A. Tavares, J. S. Martins
This paper presents the development of controllers used in active power filters, applied to improve power quality in electrical systems. These active filters can be able to compensate for the following current or voltage related problems: short blackouts, current or voltage distortion due to harmonics, current or voltage unbalance in three-phase systems, flicker and momentary over or under voltage. There are several causes for current and voltage distortion, namely, non-linear loads, some type of voltage sources and thunderstorms. These problems cause instant and long term effects on the electrical equipment. The short term effects are imperfections, malfunctioning, interferences and degradation of the performance of devices or equipments. Effects in the long run are, basically, overheating and premature aging of the electric devices. The main goal of the work described in this paper is to develop an active power filter controller based on a personal computer and a standard multifunction data acquisition PCI bus card, due to its relative low cost, high processing capability, versatility and the numerous possibilities offered by such a computer-based system. Four different approaches where tested: using C++ on Microsoft Windows with the manufacturer's device driver, using a new device driver for Windows, using Linux with real-time application interface; and using LabVIEW for Windows. Experimental and simulation results of the developed controllers are also presented.
{"title":"A personal computer based controller for an active power filter","authors":"M. Freitas, J. Afonso, A. Tavares, J. S. Martins","doi":"10.1109/ISIE.2003.1267249","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267249","url":null,"abstract":"This paper presents the development of controllers used in active power filters, applied to improve power quality in electrical systems. These active filters can be able to compensate for the following current or voltage related problems: short blackouts, current or voltage distortion due to harmonics, current or voltage unbalance in three-phase systems, flicker and momentary over or under voltage. There are several causes for current and voltage distortion, namely, non-linear loads, some type of voltage sources and thunderstorms. These problems cause instant and long term effects on the electrical equipment. The short term effects are imperfections, malfunctioning, interferences and degradation of the performance of devices or equipments. Effects in the long run are, basically, overheating and premature aging of the electric devices. The main goal of the work described in this paper is to develop an active power filter controller based on a personal computer and a standard multifunction data acquisition PCI bus card, due to its relative low cost, high processing capability, versatility and the numerous possibilities offered by such a computer-based system. Four different approaches where tested: using C++ on Microsoft Windows with the manufacturer's device driver, using a new device driver for Windows, using Linux with real-time application interface; and using LabVIEW for Windows. Experimental and simulation results of the developed controllers are also presented.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129992243","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 : 2003-06-09DOI: 10.1109/ISIE.2003.1267291
Zhang Yanqing, Wang Zhiyan, Zhou Yiqi
In this paper, the electromechanical coupling model of a tumble washing machine's drive and vibration attenuation system is put forward. In order to avoid complexity of the traditional dynamic analysis method, a method which adapts rotary reference coordinate system is presented. By analyzing the electromechanical coupling in electromechanical system, it is found that the output of the system has an influence on the drive current and output torque of motor. Rest on this relation, the active control of washing machine's drive and vibration attenuation can be achieved. This paper makes some exploration in applying nonlinear feedback decoupling control strategy to a factual system, in which two control variables Vq and Vd are employed, observers of torque disturbance and vibration amplitude are proposed, new control algorithms is put forward. In this paper, the simulation model based on computer simulation is also built, and some valuable results have been acquired. Comparing with conventional control strategy, the nonlinear feedback decoupling control strategy achieved more satisfying effect.
{"title":"An active control strategy of vibration attenuation system based on nonlinear decoupling","authors":"Zhang Yanqing, Wang Zhiyan, Zhou Yiqi","doi":"10.1109/ISIE.2003.1267291","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267291","url":null,"abstract":"In this paper, the electromechanical coupling model of a tumble washing machine's drive and vibration attenuation system is put forward. In order to avoid complexity of the traditional dynamic analysis method, a method which adapts rotary reference coordinate system is presented. By analyzing the electromechanical coupling in electromechanical system, it is found that the output of the system has an influence on the drive current and output torque of motor. Rest on this relation, the active control of washing machine's drive and vibration attenuation can be achieved. This paper makes some exploration in applying nonlinear feedback decoupling control strategy to a factual system, in which two control variables Vq and Vd are employed, observers of torque disturbance and vibration amplitude are proposed, new control algorithms is put forward. In this paper, the simulation model based on computer simulation is also built, and some valuable results have been acquired. Comparing with conventional control strategy, the nonlinear feedback decoupling control strategy achieved more satisfying effect.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"84 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134214777","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 : 2003-06-09DOI: 10.1109/ISIE.2003.1267252
K. Jezernik, G. Edelbaher
Due to its rigidness, maintenance free operation and many other advantages, the squirrel cage induction motor is the most widely used electrical motor in industrial applications. However, due to its highly coupled nonlinear structure it has certain limitations in sensorless applications in servodrives. This is due to the fact that the currently used control schemes like field oriented or direct torque control, errors occur due to the parameters variation, integral drift and noise. Those errors can be overcome with the use of the advanced parameter estimators and observers, however the speed sensorless operation, especially in the low speed region still presents a problem. Novel induction motor speed sensorless torque control is proposed. The control is quite different than the conventional field-oriented or direct torque control. First, the produced torque is explicitly continuous output variable of control. Second, a new rotor flux observer, which allows speed sensorless operation of IM by low and zero speed, was developed. A new stator and rotor flux controller/observer based on continuous sliding mode and Lyapunov theory are developed. The reference tracking performance of torque and rotor flux is demonstrated in series of transient characteristics by simulation and experimental results.
{"title":"Speed sensorless torque and flux control of induction motor","authors":"K. Jezernik, G. Edelbaher","doi":"10.1109/ISIE.2003.1267252","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267252","url":null,"abstract":"Due to its rigidness, maintenance free operation and many other advantages, the squirrel cage induction motor is the most widely used electrical motor in industrial applications. However, due to its highly coupled nonlinear structure it has certain limitations in sensorless applications in servodrives. This is due to the fact that the currently used control schemes like field oriented or direct torque control, errors occur due to the parameters variation, integral drift and noise. Those errors can be overcome with the use of the advanced parameter estimators and observers, however the speed sensorless operation, especially in the low speed region still presents a problem. Novel induction motor speed sensorless torque control is proposed. The control is quite different than the conventional field-oriented or direct torque control. First, the produced torque is explicitly continuous output variable of control. Second, a new rotor flux observer, which allows speed sensorless operation of IM by low and zero speed, was developed. A new stator and rotor flux controller/observer based on continuous sliding mode and Lyapunov theory are developed. The reference tracking performance of torque and rotor flux is demonstrated in series of transient characteristics by simulation and experimental results.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134516044","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 : 2003-06-09DOI: 10.1109/ISIE.2003.1267943
E. Bonaldi, L.E.L. de Oliveira, L. D. da Silva, G. L. Torres
The predictive maintenance applied to three-phase-induction motors through the motor current signature analysis is the highlight of the moment. Removing the fundamental component of the stator current signal is an important task in this approach. With this component extracted it is possible to improve the dynamic range of the A/D converter in order to get a more precise digitized signal and improve the failure detection. In general, notch filters are utilized to accomplish this task, but they present problems such as attenuation of some important frequencies located very close to the fundamental component which have information about a specific failure. This paper introduces the synchronous reference frame approach, generally applied to active power filters, to solve the presented problem.
{"title":"Removing the fundamental component in MCSA using the synchronous reference frame approach","authors":"E. Bonaldi, L.E.L. de Oliveira, L. D. da Silva, G. L. Torres","doi":"10.1109/ISIE.2003.1267943","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267943","url":null,"abstract":"The predictive maintenance applied to three-phase-induction motors through the motor current signature analysis is the highlight of the moment. Removing the fundamental component of the stator current signal is an important task in this approach. With this component extracted it is possible to improve the dynamic range of the A/D converter in order to get a more precise digitized signal and improve the failure detection. In general, notch filters are utilized to accomplish this task, but they present problems such as attenuation of some important frequencies located very close to the fundamental component which have information about a specific failure. This paper introduces the synchronous reference frame approach, generally applied to active power filters, to solve the presented problem.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133919466","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 : 2003-06-09DOI: 10.1109/ISIE.2003.1267957
J. Santisteban, S. Mendes, D. Sacramento
The use of magnetic bearings is very promising. The absence of mechanical friction and any type of contamination are some characteristics that justify their application in different industrial activities. To dominate this technology is necessary the study of diverse fields of electric engineering such as: electromagnetism, control, electrical machines, analog and digital systems and power electronics. Sophisticated techniques are necessary for the control of a magnetic bearing, because there are electrical non-linear relationship between the airgap and the current. In this work the fuzzy logic approach was use to design the controller. This technique allows the constructing of a control system based in a group of rules in a similar way as the human thought does. The use of this logic is justified in systems whose dynamic behavior is not well known. These rules were based on experimental results of a derivative proportional controller (PD) previously implemented and then tested through computer simulations. In order to compare theoretical results with experimental values, a test workbench was constructed. These results will be presented in this work.
{"title":"A fuzzy controller for an axial magnetic bearing","authors":"J. Santisteban, S. Mendes, D. Sacramento","doi":"10.1109/ISIE.2003.1267957","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267957","url":null,"abstract":"The use of magnetic bearings is very promising. The absence of mechanical friction and any type of contamination are some characteristics that justify their application in different industrial activities. To dominate this technology is necessary the study of diverse fields of electric engineering such as: electromagnetism, control, electrical machines, analog and digital systems and power electronics. Sophisticated techniques are necessary for the control of a magnetic bearing, because there are electrical non-linear relationship between the airgap and the current. In this work the fuzzy logic approach was use to design the controller. This technique allows the constructing of a control system based in a group of rules in a similar way as the human thought does. The use of this logic is justified in systems whose dynamic behavior is not well known. These rules were based on experimental results of a derivative proportional controller (PD) previously implemented and then tested through computer simulations. In order to compare theoretical results with experimental values, a test workbench was constructed. These results will be presented in this work.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133935637","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 : 2003-06-09DOI: 10.1109/ISIE.2003.1267899
R. Corteletti, P. R. Barros, Antonio M. N. Lima
Parameter and speed estimation in induction motors is a research topic of wide interest. Good estimates of electrical parameters and motor speed are required for designing and tuning controllers of motor drive systems. This paper compares the efficiency of different parameter estimation techniques for characterizing an induction motor supplied by a voltage source inverter. Two of the techniques belong to the so called subspace identification method to estimate linear state space models and the other, is a standard prediction error method. The comparison is based on the experimental data acquired from a laboratory prototype microcomputer-based induction motor drive system.
{"title":"Parameters estimation of induction motor using subspace methods","authors":"R. Corteletti, P. R. Barros, Antonio M. N. Lima","doi":"10.1109/ISIE.2003.1267899","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267899","url":null,"abstract":"Parameter and speed estimation in induction motors is a research topic of wide interest. Good estimates of electrical parameters and motor speed are required for designing and tuning controllers of motor drive systems. This paper compares the efficiency of different parameter estimation techniques for characterizing an induction motor supplied by a voltage source inverter. Two of the techniques belong to the so called subspace identification method to estimate linear state space models and the other, is a standard prediction error method. The comparison is based on the experimental data acquired from a laboratory prototype microcomputer-based induction motor drive system.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133336632","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 : 2003-06-09DOI: 10.1109/ISIE.2003.1267981
L.A.M. Moraes, F. J. Gomes
In this paper, the authors deal with the development of a digital environment for simulation of electronic processes. First and second orders models represent some important industrial processes. These models are present in the environment discussed on this paper. According to the authors, making of this software an important tool for operators training and teaching of engineering, specifically control and automation, adopt an educational approach. The processes are mathematically and physically modeled, allowing the user to verify the relationship between these two ways of representing a process. A high level of simplicity-of-use exists on this work because the software was developed using object-oriented language.
{"title":"Digital environment for simulation of electronic processes focused on an educational approach","authors":"L.A.M. Moraes, F. J. Gomes","doi":"10.1109/ISIE.2003.1267981","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267981","url":null,"abstract":"In this paper, the authors deal with the development of a digital environment for simulation of electronic processes. First and second orders models represent some important industrial processes. These models are present in the environment discussed on this paper. According to the authors, making of this software an important tool for operators training and teaching of engineering, specifically control and automation, adopt an educational approach. The processes are mathematically and physically modeled, allowing the user to verify the relationship between these two ways of representing a process. A high level of simplicity-of-use exists on this work because the software was developed using object-oriented language.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133345873","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 : 2003-06-09DOI: 10.1109/ISIE.2003.1267245
A. Várkonyi-Kóczy, P. Baranyi, L. Kiss, P. Várlaki
Nowadays in solving control problems the processing is performed typically by model-based computer systems, which contain a representation of our knowledge about the nature and the actual circumstances of the problem in hand. If the nature and/or the actual circumstances change the corresponding model should also be changed. Anytime techniques are very flexible in this respect and can advantageously be used when the operation should be performed under changing circumstances. In this paper, a nonlinear state dependent control methodology is proposed for anytime use and as an example is applied to globally stabilize a given prototypical aeroelastic wing section via one control surface.
{"title":"State dependent anytime control methodology for prototypical aeroelastic wing section with structural non-linearity","authors":"A. Várkonyi-Kóczy, P. Baranyi, L. Kiss, P. Várlaki","doi":"10.1109/ISIE.2003.1267245","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267245","url":null,"abstract":"Nowadays in solving control problems the processing is performed typically by model-based computer systems, which contain a representation of our knowledge about the nature and the actual circumstances of the problem in hand. If the nature and/or the actual circumstances change the corresponding model should also be changed. Anytime techniques are very flexible in this respect and can advantageously be used when the operation should be performed under changing circumstances. In this paper, a nonlinear state dependent control methodology is proposed for anytime use and as an example is applied to globally stabilize a given prototypical aeroelastic wing section via one control surface.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133184343","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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