Pub Date : 2014-12-08DOI: 10.1109/IAS.2014.6978404
P. Dost, C. Sourkounis
A drive train system (DTS) powered by an ideal voltage source and driving a permanent magnet synchronous motor (PMSM) is discussed in this paper. A two-level, three-phase conventional inverter with no harmonic filters on both AC and DC sides is used as means of power conditioning. This DTS is modelled as a double oscillator according to a simplified drive train in an electric vehicle. Commonly used pulse width modulation (PWM) based, as well as bang-bang controller (BBC) based inverter modulation schemes are applied. The influence of these modulation schemes on the performance of the DTS is determined by assessing the level of inverter generated harmonics flowing to the electric source of the DTS. The simulated results presented in the paper indicate that the pulsing frequency can be reduced by means of the hysteresis controller and that with related dispersion of the harmonic energy of the inverter generated spectrum the absence of filters in the dc-link can be partly retained.
{"title":"On influence of various modulation schemes on a PMSM within an electric Vehicle","authors":"P. Dost, C. Sourkounis","doi":"10.1109/IAS.2014.6978404","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978404","url":null,"abstract":"A drive train system (DTS) powered by an ideal voltage source and driving a permanent magnet synchronous motor (PMSM) is discussed in this paper. A two-level, three-phase conventional inverter with no harmonic filters on both AC and DC sides is used as means of power conditioning. This DTS is modelled as a double oscillator according to a simplified drive train in an electric vehicle. Commonly used pulse width modulation (PWM) based, as well as bang-bang controller (BBC) based inverter modulation schemes are applied. The influence of these modulation schemes on the performance of the DTS is determined by assessing the level of inverter generated harmonics flowing to the electric source of the DTS. The simulated results presented in the paper indicate that the pulsing frequency can be reduced by means of the hysteresis controller and that with related dispersion of the harmonic energy of the inverter generated spectrum the absence of filters in the dc-link can be partly retained.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129360005","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 : 2014-11-01DOI: 10.1109/IECON.2014.7048779
U. Chatterjee, R. Gelagaev, A. Masolin, J. Driesen
The effective efficiency of a photovoltaic system is strongly affected by varying factors such as partial shading. The centralized power conversion has limitations to mitigate that problem. As a possible solution the benefits of the distributed power conversion are explored and as an integral part of distributed power conversion an intra-module DC-DC converter is presented here to implement at substring level in photovoltaic application. In this work, the design requirements of the intra-module converter are identified and the converter is designed accordingly. The effectiveness of the designed converter is also discussed in this paper. Finally, a fully-working prototype of this converter is built and tested.
{"title":"Design of an intra-module DC-DC converter for PV application: Design considerations and prototype","authors":"U. Chatterjee, R. Gelagaev, A. Masolin, J. Driesen","doi":"10.1109/IECON.2014.7048779","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048779","url":null,"abstract":"The effective efficiency of a photovoltaic system is strongly affected by varying factors such as partial shading. The centralized power conversion has limitations to mitigate that problem. As a possible solution the benefits of the distributed power conversion are explored and as an integral part of distributed power conversion an intra-module DC-DC converter is presented here to implement at substring level in photovoltaic application. In this work, the design requirements of the intra-module converter are identified and the converter is designed accordingly. The effectiveness of the designed converter is also discussed in this paper. Finally, a fully-working prototype of this converter is built and tested.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129416225","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 : 2014-10-31DOI: 10.1109/IECON.2014.7048679
Dong Chen, Lie Xu
A dynamic performance assessment method is proposed for DC microgrids. With the control scheme modeled as virtual impedance, an actively controlled slack converter terminal of a DC network can be modeled as a circuit branch in S-domain. Using Thevenin's equivalent, transfer functions of a DC microgrid are then deduced. A control scheme is proposed to enhance the dynamics of a DC system with multiple slack terminals. A case study of a multi-terminal DC microgrid is performed to analyze and enhance its dynamics. Time domain simulation and experiments are carried out to validate the proposed analytical and enhancement method.
{"title":"DC microgrid dynamic performance assessment and enhancement based on virtual impedance method","authors":"Dong Chen, Lie Xu","doi":"10.1109/IECON.2014.7048679","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048679","url":null,"abstract":"A dynamic performance assessment method is proposed for DC microgrids. With the control scheme modeled as virtual impedance, an actively controlled slack converter terminal of a DC network can be modeled as a circuit branch in S-domain. Using Thevenin's equivalent, transfer functions of a DC microgrid are then deduced. A control scheme is proposed to enhance the dynamics of a DC system with multiple slack terminals. A case study of a multi-terminal DC microgrid is performed to analyze and enhance its dynamics. Time domain simulation and experiments are carried out to validate the proposed analytical and enhancement method.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131704101","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 : 2014-10-29DOI: 10.1109/IECON.2014.7048877
Fredrik Blomstedt, L. Ferreira, Markus Klisics, C. Chrysoulas, Iker Martínez de Soria, Brice Morin, A. Zabasta, J. Eliasson, Mats Johansson, P. Varga
The Arrowhead project aims to address the technical and applicative issues associated with cooperative automation based on Service Oriented Architectures. The problems of developing such kind of systems are mainly due to the lack of adequate development and service documentation methodologies, which would ease the burden of reusing services on different applications. The Arrowhead project proposes a technical framework to efficiently support the development of such systems, which includes several tools for documentation of services and to support the development of SOA-based installations. The work presented in this paper describes the approach which has been developed for the first generation pilots to support the documentation of their structural services. Each service, system and system-of-systems within the Arrowhead Framework must be documented and described in such way that it can be implemented, tested and deployed in an interoperable way. This paper presents the first steps of realizing the Arrowhead vision for interoperable services, systems and systems-of-systems.
{"title":"The arrowhead approach for SOA application development and documentation","authors":"Fredrik Blomstedt, L. Ferreira, Markus Klisics, C. Chrysoulas, Iker Martínez de Soria, Brice Morin, A. Zabasta, J. Eliasson, Mats Johansson, P. Varga","doi":"10.1109/IECON.2014.7048877","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048877","url":null,"abstract":"The Arrowhead project aims to address the technical and applicative issues associated with cooperative automation based on Service Oriented Architectures. The problems of developing such kind of systems are mainly due to the lack of adequate development and service documentation methodologies, which would ease the burden of reusing services on different applications. The Arrowhead project proposes a technical framework to efficiently support the development of such systems, which includes several tools for documentation of services and to support the development of SOA-based installations. The work presented in this paper describes the approach which has been developed for the first generation pilots to support the documentation of their structural services. Each service, system and system-of-systems within the Arrowhead Framework must be documented and described in such way that it can be implemented, tested and deployed in an interoperable way. This paper presents the first steps of realizing the Arrowhead vision for interoperable services, systems and systems-of-systems.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134035336","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 : 2014-10-29DOI: 10.1109/IECON.2014.7048997
Esseddik Ferdjallah-Kherkhachi, E. Schaeffer, L. Loron, M. Benbouzid
This paper investigates the online monitoring of electrical machine winding insulation systems based on the parametric modeling and identification. The proposed method consists in monitoring the drift of diagnostic indicators built from in-situ estimation of high-frequency electrical model parameters. The involved model structures are derived from the RLC network modeling of the winding insulation. Because they often present an important modeling noise, we propose to use the output error method not only to estimate the model parameter values but also to evaluate their uncertainty. This approach is based on the numerical integration of the model sensitivity functions. The so-called global identification scheme is coupled with an optimization algorithm that brings the best combination of any diagnostic model structure and its excitation protocol usable in operating conditions. Experimental data recorded from an industrial wound machines are used to illustrate the methodology.
{"title":"Online monitoring of marine turbine insulation condition based on high frequency models: Methodology for finding the \"best\" identification protocol","authors":"Esseddik Ferdjallah-Kherkhachi, E. Schaeffer, L. Loron, M. Benbouzid","doi":"10.1109/IECON.2014.7048997","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048997","url":null,"abstract":"This paper investigates the online monitoring of electrical machine winding insulation systems based on the parametric modeling and identification. The proposed method consists in monitoring the drift of diagnostic indicators built from in-situ estimation of high-frequency electrical model parameters. The involved model structures are derived from the RLC network modeling of the winding insulation. Because they often present an important modeling noise, we propose to use the output error method not only to estimate the model parameter values but also to evaluate their uncertainty. This approach is based on the numerical integration of the model sensitivity functions. The so-called global identification scheme is coupled with an optimization algorithm that brings the best combination of any diagnostic model structure and its excitation protocol usable in operating conditions. Experimental data recorded from an industrial wound machines are used to illustrate the methodology.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133854244","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 : 2014-10-29DOI: 10.1109/IECON.2014.7049093
A. Ravey, S. Faivre, Charles Higel, F. Harel, A. Djerdir
This paper proposes a novel control strategy for fuel cell electric vehicle including hydrid tanks using fuzzy logic controller. The aim of the study is to manage both thermal and electric energy with the same controller in order to use the fuel cell system as a range extender by preventing the batteries state of charge to drop too quickly. The presented controller use both batteries state of charge and thermal status of hydrid tank to control the fuel cell power. This work is a part of the Mobypost project, which aims to build and test a fleet of 10 fuel cell electric vehicles with their own refuelling hydrogen station based on hydrogen production by water electrolysis with solar panel.
{"title":"Energy management of fuel cell electric vehicle with hydrid tanks","authors":"A. Ravey, S. Faivre, Charles Higel, F. Harel, A. Djerdir","doi":"10.1109/IECON.2014.7049093","DOIUrl":"https://doi.org/10.1109/IECON.2014.7049093","url":null,"abstract":"This paper proposes a novel control strategy for fuel cell electric vehicle including hydrid tanks using fuzzy logic controller. The aim of the study is to manage both thermal and electric energy with the same controller in order to use the fuel cell system as a range extender by preventing the batteries state of charge to drop too quickly. The presented controller use both batteries state of charge and thermal status of hydrid tank to control the fuel cell power. This work is a part of the Mobypost project, which aims to build and test a fleet of 10 fuel cell electric vehicles with their own refuelling hydrogen station based on hydrogen production by water electrolysis with solar panel.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131924706","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 : 2014-10-29DOI: 10.1109/IECON.2014.7049207
K. Ahmed, A. Aboushady
One of the main challenges of voltage source converter based HVDC systems is DC faults. In this paper, two different modified half-bridge modular multilevel converter topologies are proposed. The proposed converters offer a fault tolerant against the most severe pole-to-pole DC faults. The converter comprises three switches or two switches and 4 diodes in each cell, which can result in less cost and losses compared to the full-bridge modular multilevel converter. Converter structure and controls are presented including the converter modulation and capacitors balancing. MATLAB/SIMULINK simulations are carried out to verify converter operation in normal and faulty conditions.
{"title":"Modified half-bridge modular multilevel converter for HVDC systems with DC fault ride-through capability","authors":"K. Ahmed, A. Aboushady","doi":"10.1109/IECON.2014.7049207","DOIUrl":"https://doi.org/10.1109/IECON.2014.7049207","url":null,"abstract":"One of the main challenges of voltage source converter based HVDC systems is DC faults. In this paper, two different modified half-bridge modular multilevel converter topologies are proposed. The proposed converters offer a fault tolerant against the most severe pole-to-pole DC faults. The converter comprises three switches or two switches and 4 diodes in each cell, which can result in less cost and losses compared to the full-bridge modular multilevel converter. Converter structure and controls are presented including the converter modulation and capacitors balancing. MATLAB/SIMULINK simulations are carried out to verify converter operation in normal and faulty conditions.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"759 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122989878","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 : 2014-10-29DOI: 10.1109/IECON.2014.7049263
R. Lambiase, Z. Altinbas
To increase the production of medical isotopes, an upgrade to the Brookhaven Linac Isotope Producer (BLIP) facility is now being designed and constructed. Currently, the ion beam strikes the isotope producing target in a single spot. With this upgrade, the ion beam will be directed to hit the target in circular patterns, distributing the heat of collision over a bigger area on the target. The power system to create the circular patterns requires orthogonal dipole magnets with sinusoidal currents which are ninety degrees apart from each other. This paper describes the design concept for powering the magnets and the control system that produces the correct waveforms despite component variations.
{"title":"Circular beam scanning power system for isotope production upgrade","authors":"R. Lambiase, Z. Altinbas","doi":"10.1109/IECON.2014.7049263","DOIUrl":"https://doi.org/10.1109/IECON.2014.7049263","url":null,"abstract":"To increase the production of medical isotopes, an upgrade to the Brookhaven Linac Isotope Producer (BLIP) facility is now being designed and constructed. Currently, the ion beam strikes the isotope producing target in a single spot. With this upgrade, the ion beam will be directed to hit the target in circular patterns, distributing the heat of collision over a bigger area on the target. The power system to create the circular patterns requires orthogonal dipole magnets with sinusoidal currents which are ninety degrees apart from each other. This paper describes the design concept for powering the magnets and the control system that produces the correct waveforms despite component variations.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126789486","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 : 2014-10-01DOI: 10.1109/IECON.2014.7049251
G. Escobar, C. N. Ho, S. Pettersson, G. Vázquez, Eduardo E. Ordonez-Lopez
This paper presents a discrete phase-locked loop (PLL) method aimed to provide an estimation of the angular frequency, and both the positive and negative sequences of the fundamental component of an unbalanced and distorted three-phase reference signal. The design of the proposed scheme is based on a discrete model of the generator of a three-phase signal. This model involves both positive and negative sequences of the fundamental component as well as low harmonic components. It is shown that the proposed method provides a more accurate response than discretized continuous time based PLL methods, especially in cases of digital implementation with low sampling frequency. The proposed method does not require transformation of variables into the synchronous frame coordinates as in most PLL schemes. It includes an explicit harmonic compensation mechanism to reduce the effect of harmonic distortion, and is robust against angular frequency variations, as well as sags and swells in the three-phase reference signal. Numerical results are provided to evaluate the performance of the proposed scheme. Experiments are under development at this moment, and the results will be provided in the final version of the paper.
{"title":"Discrete phase-locked loop for three-phase systems","authors":"G. Escobar, C. N. Ho, S. Pettersson, G. Vázquez, Eduardo E. Ordonez-Lopez","doi":"10.1109/IECON.2014.7049251","DOIUrl":"https://doi.org/10.1109/IECON.2014.7049251","url":null,"abstract":"This paper presents a discrete phase-locked loop (PLL) method aimed to provide an estimation of the angular frequency, and both the positive and negative sequences of the fundamental component of an unbalanced and distorted three-phase reference signal. The design of the proposed scheme is based on a discrete model of the generator of a three-phase signal. This model involves both positive and negative sequences of the fundamental component as well as low harmonic components. It is shown that the proposed method provides a more accurate response than discretized continuous time based PLL methods, especially in cases of digital implementation with low sampling frequency. The proposed method does not require transformation of variables into the synchronous frame coordinates as in most PLL schemes. It includes an explicit harmonic compensation mechanism to reduce the effect of harmonic distortion, and is robust against angular frequency variations, as well as sags and swells in the three-phase reference signal. Numerical results are provided to evaluate the performance of the proposed scheme. Experiments are under development at this moment, and the results will be provided in the final version of the paper.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"697 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115116560","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 : 2014-10-01DOI: 10.1109/IECON.2014.7048978
H. Zeroug, B. Meziane
In this paper, several control techniques for induction metal treating are examined to assess their performances using resonant series inverter. In fact, many types of steel are treated with heat to increase toughness and resistance to wear. Induction heating seems to be appropriate and provides several advantages in comparison with conventional techniques. In this paper, these techniques are evaluated comprehensively, through simulation and experiment, and compared to each other in terms of heating rate and efficiency, using one metal sample hardened to 1mm in depth up to 700°C, with a 400 W power supply. The simulation results obtained are satisfactory, and agree with those of the experiments. Furthermore, the study shows the control strategy based on frequency may not be sufficient, but should be associated with other control techniques in order to address appropriately the hardening process, bearing in mind processing time and efficiency. The strategy with frequency associated with phase shift control appears to fit well metal treating during the hardening, and can be easily tailored to its hardening requirements, compared to the other techniques.
{"title":"Open-loop control of full-bridge resonant inverter for induction metal surface heating","authors":"H. Zeroug, B. Meziane","doi":"10.1109/IECON.2014.7048978","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048978","url":null,"abstract":"In this paper, several control techniques for induction metal treating are examined to assess their performances using resonant series inverter. In fact, many types of steel are treated with heat to increase toughness and resistance to wear. Induction heating seems to be appropriate and provides several advantages in comparison with conventional techniques. In this paper, these techniques are evaluated comprehensively, through simulation and experiment, and compared to each other in terms of heating rate and efficiency, using one metal sample hardened to 1mm in depth up to 700°C, with a 400 W power supply. The simulation results obtained are satisfactory, and agree with those of the experiments. Furthermore, the study shows the control strategy based on frequency may not be sufficient, but should be associated with other control techniques in order to address appropriately the hardening process, bearing in mind processing time and efficiency. The strategy with frequency associated with phase shift control appears to fit well metal treating during the hardening, and can be easily tailored to its hardening requirements, compared to the other techniques.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123161076","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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