Pub Date : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316587
H. Maheri, D. Vinnikov, A. Chub, V. Sidorov
The galvanically isolated full-bridge series resonant quasi-Z-source dc-dc converter is studied. It features two main operating modes, buck and boost, which correspond to the converter operation above and below the nominal voltage, respectively. Power loss models are developed for both operating modes to identify the mechanism of losses. They consider switching and conduction losses in the input-side switches, core and windings losses in the transformer and the quasi-Z-source inductor, and conduction losses in the voltage doubler rectifier diodes. The developed loss models are verified at three input voltages using a 300 W experimental prototype. The inaccuracy of the developed models does not exceed 2 W, which is acceptable in comparison with the maximum estimated power loss of over 12 W. The experimental and the estimated efficiency follow the same trend. Also, the estimated efficiency exceeds the measured by no more than 1% at full power.
{"title":"Power Loss Model and Efficiency Analysis of the Quasi-Z-Source Isolated Buck-Boost Converter with Wide Input Voltage and Load Range","authors":"H. Maheri, D. Vinnikov, A. Chub, V. Sidorov","doi":"10.1109/RTUCON51174.2020.9316587","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316587","url":null,"abstract":"The galvanically isolated full-bridge series resonant quasi-Z-source dc-dc converter is studied. It features two main operating modes, buck and boost, which correspond to the converter operation above and below the nominal voltage, respectively. Power loss models are developed for both operating modes to identify the mechanism of losses. They consider switching and conduction losses in the input-side switches, core and windings losses in the transformer and the quasi-Z-source inductor, and conduction losses in the voltage doubler rectifier diodes. The developed loss models are verified at three input voltages using a 300 W experimental prototype. The inaccuracy of the developed models does not exceed 2 W, which is acceptable in comparison with the maximum estimated power loss of over 12 W. The experimental and the estimated efficiency follow the same trend. Also, the estimated efficiency exceeds the measured by no more than 1% at full power.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128674160","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 : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316552
Donato Repole, L. Adrian
VHDL language imposes some limitations, compared with the flexibility and expressiveness of other fuzzy logic oriented languages. In order to achieve behavioural modelling, a VHDL description style can be used where the system structure description (fuzzy sets, rule base etc.) and the operator description (connectives and fuzzy operations) are defined separately. It allows describing both the fuzzy system structure and the processing algorithm independently. The description format allows the use of linguistic hedges in order to compact the rules defining the system's behaviour. The paper analyses the potential advantages for the use of bespoke high-level descriptions and the feasibility of the translation into a VHDL code with a GUI interface of a controller described by a fuzzy logic oriented language. This study is encased in a particular application: Lithium-Ion Hybrid Super Capacitors management. The Lithium-Ion Hybrid Super Capacitor is a novel technology breaking new ground in the technology sector. The Lithium-Ion Hybrid Super Capacitor (LIHC) is fast evolving as the missing link between the Electric Double Layer Capacitor (EDLC) and the Lithium-Ion Battery (LIB), is a distinct hybrid of the two technologies. To be effective, it requires a management controller, which the paper targets to produce in a VHDL hardware description language.
{"title":"VHDL based Neuro-Fuzzy Lithium-Ion Hybrid Super Capacitors management: (Advantages of the high-level descriptions of neural fuzzy logic based systems)","authors":"Donato Repole, L. Adrian","doi":"10.1109/RTUCON51174.2020.9316552","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316552","url":null,"abstract":"VHDL language imposes some limitations, compared with the flexibility and expressiveness of other fuzzy logic oriented languages. In order to achieve behavioural modelling, a VHDL description style can be used where the system structure description (fuzzy sets, rule base etc.) and the operator description (connectives and fuzzy operations) are defined separately. It allows describing both the fuzzy system structure and the processing algorithm independently. The description format allows the use of linguistic hedges in order to compact the rules defining the system's behaviour. The paper analyses the potential advantages for the use of bespoke high-level descriptions and the feasibility of the translation into a VHDL code with a GUI interface of a controller described by a fuzzy logic oriented language. This study is encased in a particular application: Lithium-Ion Hybrid Super Capacitors management. The Lithium-Ion Hybrid Super Capacitor is a novel technology breaking new ground in the technology sector. The Lithium-Ion Hybrid Super Capacitor (LIHC) is fast evolving as the missing link between the Electric Double Layer Capacitor (EDLC) and the Lithium-Ion Battery (LIB), is a distinct hybrid of the two technologies. To be effective, it requires a management controller, which the paper targets to produce in a VHDL hardware description language.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127358212","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 : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316486
Līga Rozentāle, Antra Kalnbaļķīte, D. Blumberga
The research focuses on evaluating the chances of a new electricity market player - aggregator - to come into Latvian electricity market in the nearest future. Electricity market in Latvia has been liberalized since 2015 and there is a wide range of electricity suppliers competing on market basis. It is important to understand, what role could an aggregator play in this market, will it be accepted by other market participants and does it have any chances to survive in a rather small economy with much lower number of electricity consumers than in many other European Union's countries that are currently working on implementing the European Union's legislation that would allow for aggregators to operate in the electricity market.
{"title":"Aggregator as a new electricity market player: (Case study of Latvia)","authors":"Līga Rozentāle, Antra Kalnbaļķīte, D. Blumberga","doi":"10.1109/RTUCON51174.2020.9316486","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316486","url":null,"abstract":"The research focuses on evaluating the chances of a new electricity market player - aggregator - to come into Latvian electricity market in the nearest future. Electricity market in Latvia has been liberalized since 2015 and there is a wide range of electricity suppliers competing on market basis. It is important to understand, what role could an aggregator play in this market, will it be accepted by other market participants and does it have any chances to survive in a rather small economy with much lower number of electricity consumers than in many other European Union's countries that are currently working on implementing the European Union's legislation that would allow for aggregators to operate in the electricity market.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130218212","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 : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316619
Diego Di Domenico, A. Obushevs, P. Korba
with the advent of power electronics, the application of solid-state electronics for the control and conversion of electric power is substantially increasing at the expenses of simple rotating machines and linear loads. This leads to power quality problems due to the sinewave distortion of current and voltage caused by such power-electronics-based equipment. Consequently, the investigation and understanding of harmonic emissions caused by those devices become of major importance in order to assure a continuous and reliable operation of the electrical distribution grid. The following paper aims to investigate the harmonic issues in distribution grids, due to power electronic devices with particular focus on electric vehicle chargers.
{"title":"Investigation of Harmonic Issues in Distribution Grids due to High Share of Electric Vehicles","authors":"Diego Di Domenico, A. Obushevs, P. Korba","doi":"10.1109/RTUCON51174.2020.9316619","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316619","url":null,"abstract":"with the advent of power electronics, the application of solid-state electronics for the control and conversion of electric power is substantially increasing at the expenses of simple rotating machines and linear loads. This leads to power quality problems due to the sinewave distortion of current and voltage caused by such power-electronics-based equipment. Consequently, the investigation and understanding of harmonic emissions caused by those devices become of major importance in order to assure a continuous and reliable operation of the electrical distribution grid. The following paper aims to investigate the harmonic issues in distribution grids, due to power electronic devices with particular focus on electric vehicle chargers.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"214 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121105543","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 : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316589
O. Matiushkin, O. Husev, Artem Fescnko, D. Vinnikov
This document describes a new technique of the Global Maximum Power Point Tracking (GMPPT) for DC-DC converter. The GMPPT time duration was cutting by fast setting out the Short-Circuit (SC) condition. The simple Proportional Integral (PI) regulator provides a stable control of the solar panels current. The simulation results confirm theoretical statements. The real Photovoltaic (PV) string was used for the experimental investigation. Shadowing conditions lead to the second local power maximum. Finally, the key points confirmed, benefits, drawbacks are covered.
{"title":"Global MPPT for Interleaved Buck-Boost DC-DC Converter","authors":"O. Matiushkin, O. Husev, Artem Fescnko, D. Vinnikov","doi":"10.1109/RTUCON51174.2020.9316589","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316589","url":null,"abstract":"This document describes a new technique of the Global Maximum Power Point Tracking (GMPPT) for DC-DC converter. The GMPPT time duration was cutting by fast setting out the Short-Circuit (SC) condition. The simple Proportional Integral (PI) regulator provides a stable control of the solar panels current. The simulation results confirm theoretical statements. The real Photovoltaic (PV) string was used for the experimental investigation. Shadowing conditions lead to the second local power maximum. Finally, the key points confirmed, benefits, drawbacks are covered.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"204 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116150501","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 : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316474
Roberts Zemnieks, K. Vītols
Test and measurement automation is an important topic to improve test time and overall measurement quality. For this educational project, first, manual battery cell impedance measurement procedure is reviewed. Then all elements of an automated measurement system are selected or designed in Solidworks. Arduino-Matlab combination is used to design automatic control of the mechatronic system as well as to control a commercial impedance measurement device. A graphical user interface has been developed to control the system and verify its functionality.
{"title":"Automation of Battery Impedance Measurement Using Matlab","authors":"Roberts Zemnieks, K. Vītols","doi":"10.1109/RTUCON51174.2020.9316474","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316474","url":null,"abstract":"Test and measurement automation is an important topic to improve test time and overall measurement quality. For this educational project, first, manual battery cell impedance measurement procedure is reviewed. Then all elements of an automated measurement system are selected or designed in Solidworks. Arduino-Matlab combination is used to design automatic control of the mechatronic system as well as to control a commercial impedance measurement device. A graphical user interface has been developed to control the system and verify its functionality.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"2011 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125640119","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 : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316562
Ieva Pakere, Ivonna Bērziņa, Dace Lauka, D. Blumberga
The power consumption for building cooling continues to increase due to higher indoor microclimate requirements and rising outdoor temperatures in summer period. However, the information on real room cooling requirements in Latvia is not currently listed and it is a blind spot when planning solutions for energy efficient cooling system. Therefore, the article presents the methodology for determination of power for cooling purposes in educational building by using hourly power consumption data and regression models.
{"title":"Cooling load as a blind spot for energy system development","authors":"Ieva Pakere, Ivonna Bērziņa, Dace Lauka, D. Blumberga","doi":"10.1109/RTUCON51174.2020.9316562","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316562","url":null,"abstract":"The power consumption for building cooling continues to increase due to higher indoor microclimate requirements and rising outdoor temperatures in summer period. However, the information on real room cooling requirements in Latvia is not currently listed and it is a blind spot when planning solutions for energy efficient cooling system. Therefore, the article presents the methodology for determination of power for cooling purposes in educational building by using hourly power consumption data and regression models.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130336609","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 : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316563
M. Popov, S. Sarafanova, Zh. Lu
At nuclear power plants, there are particularly responsible consumers, whose accident-free operation generally affects the safety of nuclear power plants (NPPs). Some of these electric receivers operate in the normal technological cycle of power generation, while others that are particularly responsible are switched on when an emergency occurs. To ensure the reliability and safety of NPP operation in these operating modes, especially responsible consumers are started in Autonomous power supply schemes with a power source (diesel generator) of limited and comparable power. To ensure the success of the start-up of highly critical electric motors for their own needs, the NPP uses automatic step-start. The speed of a typical, standard automation algorithm is about 50–60 seconds. However, in particularly critical conditions, for example, for the power supply of mechanisms for cooling systems and accident localization, greater speed of this type of automation is required. With this requirement in mind, this article proposes and tests an adaptive algorithm for automatic accelerated step start-up (USP) of specially responsible electric motors for the NPP's own needs. The use of adaptive automatic can reduce the time of successful start-up of all engines, while excluding overloading of the diesel generator and over-regulation of the voltage in the Autonomous power supply scheme for the NPP's own needs.
{"title":"Adaptive automation of accelerated step start of engines in Autonomous power supply systems for own needs of nuclear power plants","authors":"M. Popov, S. Sarafanova, Zh. Lu","doi":"10.1109/RTUCON51174.2020.9316563","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316563","url":null,"abstract":"At nuclear power plants, there are particularly responsible consumers, whose accident-free operation generally affects the safety of nuclear power plants (NPPs). Some of these electric receivers operate in the normal technological cycle of power generation, while others that are particularly responsible are switched on when an emergency occurs. To ensure the reliability and safety of NPP operation in these operating modes, especially responsible consumers are started in Autonomous power supply schemes with a power source (diesel generator) of limited and comparable power. To ensure the success of the start-up of highly critical electric motors for their own needs, the NPP uses automatic step-start. The speed of a typical, standard automation algorithm is about 50–60 seconds. However, in particularly critical conditions, for example, for the power supply of mechanisms for cooling systems and accident localization, greater speed of this type of automation is required. With this requirement in mind, this article proposes and tests an adaptive algorithm for automatic accelerated step start-up (USP) of specially responsible electric motors for the NPP's own needs. The use of adaptive automatic can reduce the time of successful start-up of all engines, while excluding overloading of the diesel generator and over-regulation of the voltage in the Autonomous power supply scheme for the NPP's own needs.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115718470","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 : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316583
K. Kroičs, W. Martínez
The paper describes design and application of printed circuit board winding based magnetically integrated coupled inductor for interleaved DC-DC converter with high switching frequency. The paper reveals development of such magnetic component. FEMM simulation software based results are given and experimental measurement of impedance are provided. Results shows that proposed magnetic component could be beneficial in some applications.
{"title":"Design of PCB Winding Based Integrated Magnetic Component for Interleaved DC-DC Converter","authors":"K. Kroičs, W. Martínez","doi":"10.1109/RTUCON51174.2020.9316583","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316583","url":null,"abstract":"The paper describes design and application of printed circuit board winding based magnetically integrated coupled inductor for interleaved DC-DC converter with high switching frequency. The paper reveals development of such magnetic component. FEMM simulation software based results are given and experimental measurement of impedance are provided. Results shows that proposed magnetic component could be beneficial in some applications.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129667501","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 : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316548
N. Kunicina, A. Zabasta, Mārtiņš Juškāns, A. Zhiravetska, A. Patlins
High power hydraulic units play a leading role in the safety of the power supply system; its safety, or the ability to stay in work is a high priority. Therefore, attention should be focused to the safety operation of hydraulic units, diagnostics and possible forecasting and determination of the technical condition. A novel approach offered in the article allows to extend sensor data application from the production cycle monitoring to the maintenance tasks. Legacy systems contain information regarding the whole production cycle and store working conditions information from all machines. The proposed methodology aims to bridge, with the power of data mining technics and machine learning. Within the framework of the developed methodology, the weighting coefficients of the parameters characterizing the technical condition of hydraulic units have been determined and their norms and evaluation criteria have been developed. A methodology for assessing the technical condition of high power, slow-rotating hydro units has been developed, which combines knowledge from legacy systems, and data analysis of an online sensor system. The proposed system extends the basic Condition Based Management - CBM functionalities with the integration of decision support systems technologies to enhance the interaction among humans and machines, improving the performance of the maintenance. A use case of Monitoring system for proactive maintenance of hydro-turbines is also discussed in this research.
{"title":"Development of an approach for operational indicators assessment of hydro generator unit based on online sensor system data","authors":"N. Kunicina, A. Zabasta, Mārtiņš Juškāns, A. Zhiravetska, A. Patlins","doi":"10.1109/RTUCON51174.2020.9316548","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316548","url":null,"abstract":"High power hydraulic units play a leading role in the safety of the power supply system; its safety, or the ability to stay in work is a high priority. Therefore, attention should be focused to the safety operation of hydraulic units, diagnostics and possible forecasting and determination of the technical condition. A novel approach offered in the article allows to extend sensor data application from the production cycle monitoring to the maintenance tasks. Legacy systems contain information regarding the whole production cycle and store working conditions information from all machines. The proposed methodology aims to bridge, with the power of data mining technics and machine learning. Within the framework of the developed methodology, the weighting coefficients of the parameters characterizing the technical condition of hydraulic units have been determined and their norms and evaluation criteria have been developed. A methodology for assessing the technical condition of high power, slow-rotating hydro units has been developed, which combines knowledge from legacy systems, and data analysis of an online sensor system. The proposed system extends the basic Condition Based Management - CBM functionalities with the integration of decision support systems technologies to enhance the interaction among humans and machines, improving the performance of the maintenance. A use case of Monitoring system for proactive maintenance of hydro-turbines is also discussed in this research.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133556922","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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