Pub Date : 2003-06-09DOI: 10.1109/ISIE.2003.1267272
João Sena Esteves, A. Carvalho, Carlos Couto
Triangulation with active beacons is widely used in the absolute localization of mobile robots. The geometric triangulation algorithm allows the self-localization of a robot on a plane. However, the three beacons it uses must be "properly ordered" and the algorithm works consistently only when these beacons within the triangle form the robot. This paper presents an improved version of the algorithm, which does not require beacon ordering and works over the whole navigation plane except for a few well-determined lines where localization is not possible.
{"title":"Generalized geometric triangulation algorithm for mobile robot absolute self-localization","authors":"João Sena Esteves, A. Carvalho, Carlos Couto","doi":"10.1109/ISIE.2003.1267272","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267272","url":null,"abstract":"Triangulation with active beacons is widely used in the absolute localization of mobile robots. The geometric triangulation algorithm allows the self-localization of a robot on a plane. However, the three beacons it uses must be \"properly ordered\" and the algorithm works consistently only when these beacons within the triangle form the robot. This paper presents an improved version of the algorithm, which does not require beacon ordering and works over the whole navigation plane except for a few well-determined lines where localization is not possible.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"30 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":"127716257","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.2003.1267312
A. Świerniak, A. Czornik, K. Simek
The piecewise deterministic linear systems represent an interesting class of systems which can describe a large variety of processes. One of the most important area is in design of fault prone systems (see e.g. [A. Swierniak et al., 1998], [D.D. Siljak, 1980], [D.D. Sworder], where real world practical systems are discussed). In this paper. we consider the continuous time linear systems with abrupt changes of parameters modelled by discrete-state Markov processes. The changes may result from faults of actuators or sensors in the system and are localized by diagnostic equipment. Under the assumption of the existence of a suitable control law, we give the necessary and sufficient conditions for the stochastic stabilizability of the nominal model of this class of systems and optimality of the control law. Moreover assuming that the parameters of the real system may differ from their nominal values we present sufficient conditions of the robustness for the real systems.
{"title":"Robust stabilization and optimization of fault tolerant linear systems","authors":"A. Świerniak, A. Czornik, K. Simek","doi":"10.1109/ISIE.2003.1267312","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267312","url":null,"abstract":"The piecewise deterministic linear systems represent an interesting class of systems which can describe a large variety of processes. One of the most important area is in design of fault prone systems (see e.g. [A. Swierniak et al., 1998], [D.D. Siljak, 1980], [D.D. Sworder], where real world practical systems are discussed). In this paper. we consider the continuous time linear systems with abrupt changes of parameters modelled by discrete-state Markov processes. The changes may result from faults of actuators or sensors in the system and are localized by diagnostic equipment. Under the assumption of the existence of a suitable control law, we give the necessary and sufficient conditions for the stochastic stabilizability of the nominal model of this class of systems and optimality of the control law. Moreover assuming that the parameters of the real system may differ from their nominal values we present sufficient conditions of the robustness for the real systems.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"15 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":"114289761","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.2003.1267320
F. Nicolato, M.K. Madrid
This work presents hardware architecture to determine the position of objects in video images. The architecture was developed based on a programmable logic device, taking advantage of some characteristics of the standard video signals to achieve the real time operation requirements. A component-labeling algorithm is proposed to adapt the centroid determination process to the architecture. It is also presented an application example demonstrating the architecture's efficiency.
{"title":"Hardware architecture to locate multiple objects in video images","authors":"F. Nicolato, M.K. Madrid","doi":"10.1109/ISIE.2003.1267320","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267320","url":null,"abstract":"This work presents hardware architecture to determine the position of objects in video images. The architecture was developed based on a programmable logic device, taking advantage of some characteristics of the standard video signals to achieve the real time operation requirements. A component-labeling algorithm is proposed to adapt the centroid determination process to the architecture. It is also presented an application example demonstrating the architecture's efficiency.","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":"131349105","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.2003.1267901
M. Manic, B. Wilamowski
Proposed algorithm exhibits 2 significant advantages: easier hardware implementation and robust convergence. Proposed algorithm considers one hidden layer neural network architecture and consists of following major phases. First phase is reduction of weight set. Second phase is gradient calculation on such compressed network. Search for weights is done only in the input layer, while output layer is trained always with pseudo-inversion training. Algorithm is further improved with adaptive network parameters. Final algorithm behavior exhibits robust and fast convergence. Experimental results are illustrated by figures and tables.
{"title":"Random weights search in compressed neural networks using overdetermined pseudoinverse","authors":"M. Manic, B. Wilamowski","doi":"10.1109/ISIE.2003.1267901","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267901","url":null,"abstract":"Proposed algorithm exhibits 2 significant advantages: easier hardware implementation and robust convergence. Proposed algorithm considers one hidden layer neural network architecture and consists of following major phases. First phase is reduction of weight set. Second phase is gradient calculation on such compressed network. Search for weights is done only in the input layer, while output layer is trained always with pseudo-inversion training. Algorithm is further improved with adaptive network parameters. Final algorithm behavior exhibits robust and fast convergence. Experimental results are illustrated by figures and tables.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"28 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114006191","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.2003.1267946
A. Yamamoto, H. Yasui, T. Nishijima, T. Higuchi
A high-power electrostatic linear servo motor stage for vacuum environment has been developed. The stage is equipped with integrated built-in position sensor that uses the motor's electrode for position sensing. This stage is characterized by compact structure and low magnetic field emission. It can work within sufficiently small space in a vacuum chamber without disturbing surrounding electro-magnetic field. Therefore this motor stage could be highly compatible with many vacuum applications that utilize electron beam. In this paper, basic structure of the motor is described. The motor is sized 145 mm in length, 125 mm in width, and 40 mm in height. The stage is equipped with two thin plastic films, which contain three-phase electrodes aligned with an interval of 200 /spl mu/m. Those two films are attached to slider and stator, respectively, to generate electrostatic thrust force. Linear cross-roller guide supports the slider. The stroke is 40 mm. The estimated thrust force in 10/sup -3/ Pa is 1.2 N with an applied voltage of 1.6 kV/sub 0-p/. We have developed built-in position sensor for positioning servo control. Detail of built-in position sensor and results of positioning control are reported.
{"title":"Electrostatic linear servo motor with built-in position sensor for vacuum environment","authors":"A. Yamamoto, H. Yasui, T. Nishijima, T. Higuchi","doi":"10.1109/ISIE.2003.1267946","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267946","url":null,"abstract":"A high-power electrostatic linear servo motor stage for vacuum environment has been developed. The stage is equipped with integrated built-in position sensor that uses the motor's electrode for position sensing. This stage is characterized by compact structure and low magnetic field emission. It can work within sufficiently small space in a vacuum chamber without disturbing surrounding electro-magnetic field. Therefore this motor stage could be highly compatible with many vacuum applications that utilize electron beam. In this paper, basic structure of the motor is described. The motor is sized 145 mm in length, 125 mm in width, and 40 mm in height. The stage is equipped with two thin plastic films, which contain three-phase electrodes aligned with an interval of 200 /spl mu/m. Those two films are attached to slider and stator, respectively, to generate electrostatic thrust force. Linear cross-roller guide supports the slider. The stroke is 40 mm. The estimated thrust force in 10/sup -3/ Pa is 1.2 N with an applied voltage of 1.6 kV/sub 0-p/. We have developed built-in position sensor for positioning servo control. Detail of built-in position sensor and results of positioning control are reported.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"18 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":"123860795","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.2003.1267963
R. Costa, N.R.S. dos Reis, L. Hsu, A. J. Peixoto, P. Gomes
This paper reports the development and experimental evaluation of robotized system devised to perform two kinds of measurements inside a pipeline: the thickness of the internal wall painting layer and the internal radius. The thickness measurement allows the inspection of the painting layer quality and, by measuring several radii, it is possible to estimate that pipeline transversal section shape. The proposed scheme is shown to yield very satisfactory results on an actual pipeline.
{"title":"Robotized system for in-pipe inspection","authors":"R. Costa, N.R.S. dos Reis, L. Hsu, A. J. Peixoto, P. Gomes","doi":"10.1109/ISIE.2003.1267963","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267963","url":null,"abstract":"This paper reports the development and experimental evaluation of robotized system devised to perform two kinds of measurements inside a pipeline: the thickness of the internal wall painting layer and the internal radius. The thickness measurement allows the inspection of the painting layer quality and, by measuring several radii, it is possible to estimate that pipeline transversal section shape. The proposed scheme is shown to yield very satisfactory results on an actual pipeline.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"13 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":"124418923","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.2003.1267326
S. Halász
In the area of high voltages and powers, a high quality inverter-fed ac drive is more easily obtained by the use of multi-level inverters. For three-level inverters three different PWM control regions can be introduced where different two-phase (discontinuous) PWM strategies and the different three-phase ones should be applied. This paper deals with the analysis of voltage spectra of different PWM methods for region I of three-level inverters and especially with those two PWM methods that are not used in the case of two-level inverters. The derivation of the analytical equations of motor voltage harmonics for these PWM methods is given. The comparisons of the voltage spectra of the possible PWM methods are presented. It is shown that for the first half of region I (low voltage area) the best solution is the use of dipolar modulation. However, for the second half of this region the harmonic losses associated with dipolar modulation can be sharply decreased by the application of the other three-phase PWM technique. At the same time for two-level inverters this PWM technique produces no acceptable solution.
{"title":"Voltage spectra of three-level inverters","authors":"S. Halász","doi":"10.1109/ISIE.2003.1267326","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267326","url":null,"abstract":"In the area of high voltages and powers, a high quality inverter-fed ac drive is more easily obtained by the use of multi-level inverters. For three-level inverters three different PWM control regions can be introduced where different two-phase (discontinuous) PWM strategies and the different three-phase ones should be applied. This paper deals with the analysis of voltage spectra of different PWM methods for region I of three-level inverters and especially with those two PWM methods that are not used in the case of two-level inverters. The derivation of the analytical equations of motor voltage harmonics for these PWM methods is given. The comparisons of the voltage spectra of the possible PWM methods are presented. It is shown that for the first half of region I (low voltage area) the best solution is the use of dipolar modulation. However, for the second half of this region the harmonic losses associated with dipolar modulation can be sharply decreased by the application of the other three-phase PWM technique. At the same time for two-level inverters this PWM technique produces no acceptable solution.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"25 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":"124522513","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.2003.1267906
L. Horváth, I. Rudas, J. Tar
Researchers and practitioners have attempted to solve problem of robot control by using of well-proved product models. Existing product modeling methods offer quasi integration because appropriate integrated robot process model is not available. The authors propose a modeling of the robot system that has the capability of integrated description of product, robot and robot process. Advanced concepts as feature and associativity definitions together with task oriented robot process gained an extended application in the proposed model. This paper presents the new modeling for integrated application of part, assembly and robot process models at robot assembly of mechanical products. The main purpose of this integration is product model driven definition of robot assembly trajectories. The main contribution is an attempt to define shapes and part positions for robot assembly by using of form features instead of geometric elements. Form feature model objects carry intent of engineers for technical content of modeled environment. The paper introduces actual issues of robot assembly and outlines the concept of the authors for product model driven modeling of robot assembly. Information for assembly in feature based product model and robot process model features are explained. Following this, an extended feature concept for modeling of robot system is discussed. Finally, integrated model of robot assembly system and role of form features in it are concluded.
{"title":"Robot assembly trajectory generation using form feature driven robot process model","authors":"L. Horváth, I. Rudas, J. Tar","doi":"10.1109/ISIE.2003.1267906","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267906","url":null,"abstract":"Researchers and practitioners have attempted to solve problem of robot control by using of well-proved product models. Existing product modeling methods offer quasi integration because appropriate integrated robot process model is not available. The authors propose a modeling of the robot system that has the capability of integrated description of product, robot and robot process. Advanced concepts as feature and associativity definitions together with task oriented robot process gained an extended application in the proposed model. This paper presents the new modeling for integrated application of part, assembly and robot process models at robot assembly of mechanical products. The main purpose of this integration is product model driven definition of robot assembly trajectories. The main contribution is an attempt to define shapes and part positions for robot assembly by using of form features instead of geometric elements. Form feature model objects carry intent of engineers for technical content of modeled environment. The paper introduces actual issues of robot assembly and outlines the concept of the authors for product model driven modeling of robot assembly. Information for assembly in feature based product model and robot process model features are explained. Following this, an extended feature concept for modeling of robot system is discussed. Finally, integrated model of robot assembly system and role of form features in it are concluded.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"325 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":"124590843","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.2003.1267258
F.D. Dantas, C. Canesin
This paper describes a novel high frequency ac voltage-regulator using a single ended primary inductance converter as power stage, and active power factor correction through the use of variable hysteresis control technique. The main advantage of this ac voltage-regulator concerns with the smaller volume, and size than the conventional ones. Nowadays, due to power quality standards, high input power factor is a necessity for power electronic converters, to perform that the input current total harmonic distortion (THB) fits into the limits of the standards, like IEC 61000-3-2 limits. It should be noticed that the input current THD for the novel ac high frequency voltage-regulator are in agreement with the requirements defined in the IEC 61000-3-2 standards. This paper presents a complete analysis, design and simulation results for a prototype rated at 300 W, operating with variable switching frequency (30 Hz until 90 kHz), and 127Vrms of nominal output voltages.
{"title":"A novel high frequency ac voltage regulator with active power factor correction","authors":"F.D. Dantas, C. Canesin","doi":"10.1109/ISIE.2003.1267258","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267258","url":null,"abstract":"This paper describes a novel high frequency ac voltage-regulator using a single ended primary inductance converter as power stage, and active power factor correction through the use of variable hysteresis control technique. The main advantage of this ac voltage-regulator concerns with the smaller volume, and size than the conventional ones. Nowadays, due to power quality standards, high input power factor is a necessity for power electronic converters, to perform that the input current total harmonic distortion (THB) fits into the limits of the standards, like IEC 61000-3-2 limits. It should be noticed that the input current THD for the novel ac high frequency voltage-regulator are in agreement with the requirements defined in the IEC 61000-3-2 standards. This paper presents a complete analysis, design and simulation results for a prototype rated at 300 W, operating with variable switching frequency (30 Hz until 90 kHz), and 127Vrms of nominal output voltages.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"37 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":"115581681","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.2003.1267936
M.M. Santos, M. Stemmer, F. Vasques
Due to the increased availability of low cost network technology, the use of networks to interconnect sensors, actuators and controllers is becoming widely accepted for the implementation of feedback control systems. Such type of feedback implementation, wherein the control loops are closed through a real-time network, are called network controlled systems (NCS). When implementing a NCS, the underlying communication network must provide a timely communication service, which must be adequate to fulfill the control application requirements. Therefore, the assessment of the network responsiveness to the real-time requirements of the control application is a fundamental issue. Both PROFIBUS and CAN networks are usually considered suitable to support small-scale NCS, due to their real-time capabilities. However their temporal responsiveness is highly dependent on both the timing characteristics of the supported message streams, such as its periodicity and the related message lengths. In this paper, we compare the timing properties of both CAN and PROFIBUS control networks. Basically, we assess their capability to support network controlled systems, through the evaluation of the related worst-case message's response time. A small example of a NCS is then used to assess the capability of the CAN control network to fulfill control application requirements.
{"title":"Evaluation of the timing properties of two control networks: CAN and PROFIBUS","authors":"M.M. Santos, M. Stemmer, F. Vasques","doi":"10.1109/ISIE.2003.1267936","DOIUrl":"https://doi.org/10.1109/ISIE.2003.1267936","url":null,"abstract":"Due to the increased availability of low cost network technology, the use of networks to interconnect sensors, actuators and controllers is becoming widely accepted for the implementation of feedback control systems. Such type of feedback implementation, wherein the control loops are closed through a real-time network, are called network controlled systems (NCS). When implementing a NCS, the underlying communication network must provide a timely communication service, which must be adequate to fulfill the control application requirements. Therefore, the assessment of the network responsiveness to the real-time requirements of the control application is a fundamental issue. Both PROFIBUS and CAN networks are usually considered suitable to support small-scale NCS, due to their real-time capabilities. However their temporal responsiveness is highly dependent on both the timing characteristics of the supported message streams, such as its periodicity and the related message lengths. In this paper, we compare the timing properties of both CAN and PROFIBUS control networks. Basically, we assess their capability to support network controlled systems, through the evaluation of the related worst-case message's response time. A small example of a NCS is then used to assess the capability of the CAN control network to fulfill control application requirements.","PeriodicalId":166431,"journal":{"name":"2003 IEEE International Symposium on Industrial Electronics ( Cat. No.03TH8692)","volume":"13 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":"125108674","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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