Pub Date : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960498
F. Aboura, A. Touhami, A. Zama, R. Tahmi, O. Touhami
This paper deals with to elaborate a model of single-phase core type transformer. The model uses the principle of duality based on corrections made to the Π-model. First, we will highlight modifications to already existing models, and a comparison between the Modified Π-model with the T and Π-models and experimentation will be made. The main interest of this model is to introduce of hysteresis loop instead of an anhystretic curve in both T and especially in the Π-model that seeks to improve. The hysteresis loop can have an important role in the simulation of the transient phenomena, such as ferroresonance. Also, for the correction of the Π-model and T-model, we include the hysteresis reactor in the elements of the transformer core to model the non-linear effects of hysteresis, and saturation.
{"title":"Modeling of single-phase core type transformer","authors":"F. Aboura, A. Touhami, A. Zama, R. Tahmi, O. Touhami","doi":"10.1109/ICELMACH.2014.6960498","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960498","url":null,"abstract":"This paper deals with to elaborate a model of single-phase core type transformer. The model uses the principle of duality based on corrections made to the Π-model. First, we will highlight modifications to already existing models, and a comparison between the Modified Π-model with the T and Π-models and experimentation will be made. The main interest of this model is to introduce of hysteresis loop instead of an anhystretic curve in both T and especially in the Π-model that seeks to improve. The hysteresis loop can have an important role in the simulation of the transient phenomena, such as ferroresonance. Also, for the correction of the Π-model and T-model, we include the hysteresis reactor in the elements of the transformer core to model the non-linear effects of hysteresis, and saturation.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126072094","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960276
Zach Pan, J. Ikaheimo
Multiphase variable speed drive systems have gained more and more interest recently because of their lower torque ripple as a result of the harmonic cancellation effects between phases. This paper presents a nine phase variable speed drive system with reduced frequency PWM control scheme. The proposed PWM scheme is tailored for multiphase winding to reduce torque ripple and associated rotor losses. Even though the line current has fairly high harmonic contents, there is no significant power losses increase in the motor. On the other hand, the power converter can benefit significantly from the reduced switching frequency and switching losses. Simulation results and experimental results on a 160 kW 9-phase motor have been shown to support the conclusion.
{"title":"Nine-phase variable speed drive system with reduced switching PWM","authors":"Zach Pan, J. Ikaheimo","doi":"10.1109/ICELMACH.2014.6960276","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960276","url":null,"abstract":"Multiphase variable speed drive systems have gained more and more interest recently because of their lower torque ripple as a result of the harmonic cancellation effects between phases. This paper presents a nine phase variable speed drive system with reduced frequency PWM control scheme. The proposed PWM scheme is tailored for multiphase winding to reduce torque ripple and associated rotor losses. Even though the line current has fairly high harmonic contents, there is no significant power losses increase in the motor. On the other hand, the power converter can benefit significantly from the reduced switching frequency and switching losses. Simulation results and experimental results on a 160 kW 9-phase motor have been shown to support the conclusion.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121712797","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960229
Stig Högberg, H. Hansen, B. B. Jensen, F. B. Bendixen
Permanent magnet couplings are widely used in applications requiring torque to be transmitted through an airgap. The aim of this study is to observe and explain the effect of radial and axial misalignment in a 12-pole, cylindrical permanent magnet coupling. Pull-out torque was measured for two coupling pairs which showed an increase of 3.1% and 3.8%, respectively, at maximum radial misalignment. When modeled in finite element analysis software, the coupling produces 3.7% more static pull-out torque than the aligned case. For axial misalignment the pull-out torque at different misalignment distances was measured and simulated. An insignificant reduction in pull-out torque was observed for small misalignment, whereas it decreases linearly with misalignment distance when above 3-4 mm. These results show that radial and axial misalignment do not adversely affect static torque performance, though the affect on non-static performance is not considered and may be detrimental.
{"title":"Influence of end-effects on static torque performance of misaligned cylindrical permanent magnet couplings","authors":"Stig Högberg, H. Hansen, B. B. Jensen, F. B. Bendixen","doi":"10.1109/ICELMACH.2014.6960229","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960229","url":null,"abstract":"Permanent magnet couplings are widely used in applications requiring torque to be transmitted through an airgap. The aim of this study is to observe and explain the effect of radial and axial misalignment in a 12-pole, cylindrical permanent magnet coupling. Pull-out torque was measured for two coupling pairs which showed an increase of 3.1% and 3.8%, respectively, at maximum radial misalignment. When modeled in finite element analysis software, the coupling produces 3.7% more static pull-out torque than the aligned case. For axial misalignment the pull-out torque at different misalignment distances was measured and simulated. An insignificant reduction in pull-out torque was observed for small misalignment, whereas it decreases linearly with misalignment distance when above 3-4 mm. These results show that radial and axial misalignment do not adversely affect static torque performance, though the affect on non-static performance is not considered and may be detrimental.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121360307","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960507
N. Papanikolaou, A. Kyritsis, Michael Loupis
This paper presents two different approaches for the incorporation of commercial inverters in ships' low voltage electric network, either for the exploitation of renewable sources such as the sun and the wind, or for energy regeneration from the exhaust gases heat. Both solutions contribute to the reduction of CO2 emissions as well as to fuel consumption reduction. The inverters as well as all the necessary installation components should meet the requirements for Safety of Life at Sea (SOLAS) as they are reported on IEC 60092 or IEEE 45 series and are a part of ABS rules - approved from national and international register of shipping organizations.
{"title":"Incorporating power converters for energy saving marine applications","authors":"N. Papanikolaou, A. Kyritsis, Michael Loupis","doi":"10.1109/ICELMACH.2014.6960507","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960507","url":null,"abstract":"This paper presents two different approaches for the incorporation of commercial inverters in ships' low voltage electric network, either for the exploitation of renewable sources such as the sun and the wind, or for energy regeneration from the exhaust gases heat. Both solutions contribute to the reduction of CO2 emissions as well as to fuel consumption reduction. The inverters as well as all the necessary installation components should meet the requirements for Safety of Life at Sea (SOLAS) as they are reported on IEC 60092 or IEEE 45 series and are a part of ABS rules - approved from national and international register of shipping organizations.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125280808","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960261
Y. Sim, N. Niguchi, K. Hirata, Cheong-worl Kim
To control sensorless type Brushless DC (BLDC) motors, various back Electromotive Force (EMF) detecting methods have been widely used. In this research, a Finite Elements Method (FEM) model of an 8 pole 12 slot BLDC motor and two kinds of phase-voltage sensing back EMF detecting electrical circuits are coupled to achieve improved and more reliable analysis results. Through this coupled analysis, it becomes possible to analyze the characteristics of the motor and how the electrical circuit affects the motor at the same time. This makes it possible to design high performance embedded motor controllers in the future. An experimental evaluation of the coupled analysis results was also implemented to verify the coupled analysis.
{"title":"Coupled analysis of brushless DC motor using finite elements method & back electromotive force detecting electrical circuits","authors":"Y. Sim, N. Niguchi, K. Hirata, Cheong-worl Kim","doi":"10.1109/ICELMACH.2014.6960261","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960261","url":null,"abstract":"To control sensorless type Brushless DC (BLDC) motors, various back Electromotive Force (EMF) detecting methods have been widely used. In this research, a Finite Elements Method (FEM) model of an 8 pole 12 slot BLDC motor and two kinds of phase-voltage sensing back EMF detecting electrical circuits are coupled to achieve improved and more reliable analysis results. Through this coupled analysis, it becomes possible to analyze the characteristics of the motor and how the electrical circuit affects the motor at the same time. This makes it possible to design high performance embedded motor controllers in the future. An experimental evaluation of the coupled analysis results was also implemented to verify the coupled analysis.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131361956","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960422
Á. Sapena-Bañó, J. Martínez-Román, J. Pérez-Cruz, M. Pineda-Sánchez, J. Roger-Folch, M. Riera-Guasp, R. Puche-Panadero
Improved fault diagnostic techniques in wind turbines is a field of growing interest, given the negative impact that unexpected breakdowns have on the profitability of wind farms. New diagnostic techniques based on generator currents monitoring have recently been developed, but their use is still irrelevant despite the advantages that current monitoring presents versus monitoring vibrations. In part, this situation can be due to the needs of relatively high computing power not available in the wind-groups and also, to the use of signals that generate volumes of data difficult to transfer to control centers, where they could be processed. This paper introduces a methodology that aims to solve these problems. In this paper a novel diagnostic method based on monitoring the generator currents is proposed. This approach is based on the tracking analysis of the fault components using the harmonic order as independent variable. This approach can be implemented in low cost digital devices; the resultant patterns are very simple, since their shape is the same no matter the changes in the fundamental frequency and thus, are easily interpretable even by non-qualified persons. Moreover these patterns are characterized by a very low number of parameters, which make easy their transmission to remote control centers. This new approach is theoretically justified and validated by laboratory tests.
{"title":"Harmonic order tracking analysis: A novel method for the diagnosis of induction generators","authors":"Á. Sapena-Bañó, J. Martínez-Román, J. Pérez-Cruz, M. Pineda-Sánchez, J. Roger-Folch, M. Riera-Guasp, R. Puche-Panadero","doi":"10.1109/ICELMACH.2014.6960422","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960422","url":null,"abstract":"Improved fault diagnostic techniques in wind turbines is a field of growing interest, given the negative impact that unexpected breakdowns have on the profitability of wind farms. New diagnostic techniques based on generator currents monitoring have recently been developed, but their use is still irrelevant despite the advantages that current monitoring presents versus monitoring vibrations. In part, this situation can be due to the needs of relatively high computing power not available in the wind-groups and also, to the use of signals that generate volumes of data difficult to transfer to control centers, where they could be processed. This paper introduces a methodology that aims to solve these problems. In this paper a novel diagnostic method based on monitoring the generator currents is proposed. This approach is based on the tracking analysis of the fault components using the harmonic order as independent variable. This approach can be implemented in low cost digital devices; the resultant patterns are very simple, since their shape is the same no matter the changes in the fundamental frequency and thus, are easily interpretable even by non-qualified persons. Moreover these patterns are characterized by a very low number of parameters, which make easy their transmission to remote control centers. This new approach is theoretically justified and validated by laboratory tests.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121785802","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960514
Y. Gritli, A. Tani, M. Mengoni, L. Zarri, G. Serra, F. Filippetti, D. Casadei
Multiphase permanent-magnet generators are an attractive alternative for a variety of emerging applications owing to their reliability and dynamic performance such as hybrid traction systems. In this context, diagnosing the status of the rotor magnets is crucial for improving the reliability of the generators. The effect of the closed-loop control system cannot be neglected when the fault detection process is based on the signature analysis of electrical variables. Therefore, investigating the relevance of the bandwidth of the control system on the induced fault component is mandatory. In this paper, the detectability of the demagnetization of the rotor magnet trailing edges, due to large stator currents, in five-phase surface-mounted permanent magnet synchronous generators, is investigated. The theoretical analysis is validated by means of numerical simulations.
{"title":"Effect of the closed-loop control on the diagnosis of rotor demagnetization in five-phase surface-mounted permanent magnet generators","authors":"Y. Gritli, A. Tani, M. Mengoni, L. Zarri, G. Serra, F. Filippetti, D. Casadei","doi":"10.1109/ICELMACH.2014.6960514","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960514","url":null,"abstract":"Multiphase permanent-magnet generators are an attractive alternative for a variety of emerging applications owing to their reliability and dynamic performance such as hybrid traction systems. In this context, diagnosing the status of the rotor magnets is crucial for improving the reliability of the generators. The effect of the closed-loop control system cannot be neglected when the fault detection process is based on the signature analysis of electrical variables. Therefore, investigating the relevance of the bandwidth of the control system on the induced fault component is mandatory. In this paper, the detectability of the demagnetization of the rotor magnet trailing edges, due to large stator currents, in five-phase surface-mounted permanent magnet synchronous generators, is investigated. The theoretical analysis is validated by means of numerical simulations.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115159232","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960157
J. W. Tsotie, R. Wamkeue
The paper is concerned with practical modelling of the synchronous generator (SG) as the main component of the hydroelectric power plant. The generation system under study comprises the hydraulic circuit, the speed regulator, the excitation system and the SG. Each system component is formatted into state form. The SG state model developed with field voltage as the only controlled input variable and with stator currents, field currents and stator voltages as output observed variables, includes both the saturation phenomenon and the mechanical motion. The resulting flexible SG model connected to other power plant components allows predicting various tests such as: the classical three-phase sudden short-circuit test, the field short-circuit test with the stator in open circuit and the load rejection and line-switching tests. In order to prove the effectiveness of the proposed power plant modeling framework, extensive simulations using the Matlab/Simulink program are performed and discussed for different tests and plant scenarios (automatic voltage regulator (AVR) on and off).
{"title":"An efficient model of synchronous generator for hydraulic power plant dynamic simulations","authors":"J. W. Tsotie, R. Wamkeue","doi":"10.1109/ICELMACH.2014.6960157","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960157","url":null,"abstract":"The paper is concerned with practical modelling of the synchronous generator (SG) as the main component of the hydroelectric power plant. The generation system under study comprises the hydraulic circuit, the speed regulator, the excitation system and the SG. Each system component is formatted into state form. The SG state model developed with field voltage as the only controlled input variable and with stator currents, field currents and stator voltages as output observed variables, includes both the saturation phenomenon and the mechanical motion. The resulting flexible SG model connected to other power plant components allows predicting various tests such as: the classical three-phase sudden short-circuit test, the field short-circuit test with the stator in open circuit and the load rejection and line-switching tests. In order to prove the effectiveness of the proposed power plant modeling framework, extensive simulations using the Matlab/Simulink program are performed and discussed for different tests and plant scenarios (automatic voltage regulator (AVR) on and off).","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127710548","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960354
A. Nollau, D. Gerling
This paper presents new cooling methods for permanent magnet synchronous machines (PMSM) with flux barriers. For a vehicle powertrain application the permanent magnet synchronous machines is a very popular choice, because of high power density, a high efficiency and the small package. However, this machine is susceptible to suffer insulations failures of coils and demagnetization of magnets under severe thermal condition. Therefore, it is important to have an efficient cooling method for the PMSM to generate high heat dissipation. The configurations of the new cooling methods are presented in this paper. Three different topologies are compared with a standard water cooling jacket configuration. A finite volume Computational Fluid Dynamic (CFD) model is applied to have a very accurate and comprehensive simulation.
{"title":"Novel cooling methods using flux-barriers","authors":"A. Nollau, D. Gerling","doi":"10.1109/ICELMACH.2014.6960354","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960354","url":null,"abstract":"This paper presents new cooling methods for permanent magnet synchronous machines (PMSM) with flux barriers. For a vehicle powertrain application the permanent magnet synchronous machines is a very popular choice, because of high power density, a high efficiency and the small package. However, this machine is susceptible to suffer insulations failures of coils and demagnetization of magnets under severe thermal condition. Therefore, it is important to have an efficient cooling method for the PMSM to generate high heat dissipation. The configurations of the new cooling methods are presented in this paper. Three different topologies are compared with a standard water cooling jacket configuration. A finite volume Computational Fluid Dynamic (CFD) model is applied to have a very accurate and comprehensive simulation.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128089034","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960504
K. Nikolaou, M. Beniakar, A. Kladas
This paper proposes a shape optimization procedure to design a three phase squirrel cage induction motor. For the purposes of the analysis, on a first step, preliminary motor design using classical analytical techniques is employed. On a second step, the parameterization of the design and extended sensitivity analysis of the stator and rotor geometrical parameters using Finite Element (FE) models is performed. Finally, the calculation of the per-phase equivalent circuit of variable parameters, incorporating the results of the FE model, enables the comparison of the results produced by the two methods. The procedure is applied to the design of an induction motor for ship thruster propulsion.
{"title":"Design considerations in induction motors for ship thruster propulsion","authors":"K. Nikolaou, M. Beniakar, A. Kladas","doi":"10.1109/ICELMACH.2014.6960504","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960504","url":null,"abstract":"This paper proposes a shape optimization procedure to design a three phase squirrel cage induction motor. For the purposes of the analysis, on a first step, preliminary motor design using classical analytical techniques is employed. On a second step, the parameterization of the design and extended sensitivity analysis of the stator and rotor geometrical parameters using Finite Element (FE) models is performed. Finally, the calculation of the per-phase equivalent circuit of variable parameters, incorporating the results of the FE model, enables the comparison of the results produced by the two methods. The procedure is applied to the design of an induction motor for ship thruster propulsion.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"159 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133349383","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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