Pub Date : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316621
A. Anuchin, D. Shpak, A. Kotelnikova, Alexey Dmitriev, A. Bogdanov, G. Demidova
One of the promising technologies of encoderless rotor position and speed estimation for the motors with magnetic anisotropy is the analysis of operation of model predictive control. Idea of the method is to track the difference between the prediction and actual behaviour of the motor currents which should match if the rotor position estimation is correct. However, this method was not applied for switched reluctance drive yet. This paper proposes the rotor position and speed estimator for switched reluctance motor operated under continuous control set model predictive control. It implements phase-locked loop fed by the error between the referenced current and it actual value. The estimator was examined using a simulation model and provides fast and accurate speed and position tracking.
{"title":"Encoderless Rotor Position Estimation of a Switched Reluctance Drive Operated under Model Predictive Control","authors":"A. Anuchin, D. Shpak, A. Kotelnikova, Alexey Dmitriev, A. Bogdanov, G. Demidova","doi":"10.1109/RTUCON51174.2020.9316621","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316621","url":null,"abstract":"One of the promising technologies of encoderless rotor position and speed estimation for the motors with magnetic anisotropy is the analysis of operation of model predictive control. Idea of the method is to track the difference between the prediction and actual behaviour of the motor currents which should match if the rotor position estimation is correct. However, this method was not applied for switched reluctance drive yet. This paper proposes the rotor position and speed estimator for switched reluctance motor operated under continuous control set model predictive control. It implements phase-locked loop fed by the error between the referenced current and it actual value. The estimator was examined using a simulation model and provides fast and accurate speed and position tracking.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121768192","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/RTUCON51174.2020.9316600
J. Kozadajevs, D. Boreiko
Using combined heat and power plants (CHPP) is widespread in the Nordic countries, where district heating as a thermal load for CHPPs is typical for cities and towns. However, CHPP operation becomes more complicated at power market conditions. Errors in the forecasting of the temperature, which lies at the basis of CHPP operation mode planning (the difference between forecasted heat demand and the real one leads to a difference between planned and real electricity production), lead to an imbalance in electricity production in the day-ahead market. To improve CHPP profitability at power market conditions, different technologies are used to increase CHPP operation flexibility. The overall objective of this study is to evaluate, based on the example of the city of Riga, what possibilities of flexibility for each hour can be provided by the inertia of the heating system of Riga at possible temperature deviations from the comfort temperature.
{"title":"District Heating System Flexibility Studies Using Thermal Inertia of Buildings","authors":"J. Kozadajevs, D. Boreiko","doi":"10.1109/RTUCON51174.2020.9316600","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316600","url":null,"abstract":"Using combined heat and power plants (CHPP) is widespread in the Nordic countries, where district heating as a thermal load for CHPPs is typical for cities and towns. However, CHPP operation becomes more complicated at power market conditions. Errors in the forecasting of the temperature, which lies at the basis of CHPP operation mode planning (the difference between forecasted heat demand and the real one leads to a difference between planned and real electricity production), lead to an imbalance in electricity production in the day-ahead market. To improve CHPP profitability at power market conditions, different technologies are used to increase CHPP operation flexibility. The overall objective of this study is to evaluate, based on the example of the city of Riga, what possibilities of flexibility for each hour can be provided by the inertia of the heating system of Riga at possible temperature deviations from the comfort temperature.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122335185","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/RTUCON51174.2020.9316596
A. Mahņitko, T. Lomane, I. Zicmane, Timurs Kuzņecovs, Jurijs Silinevics
With the restoration of the Baltic States independence, they faced problems both of a political and economic nature. First of all, these problems were caused by the need to strengthen the energy independence of the Baltic States, since historically its power systems worked in synchronous mode with the United power system of Russia, depending on its mode of operation. It was the Baltic States' desire to eliminate energy dependence on a single energy supplier that determined their desire to integrate their transmission networks into the electrical system of continental Europe. The solution to this problem allows the Baltic States to strengthen their energy independence and become a full participant in the electricity market of continental Europe. Aspects of integration of the Baltic power systems with the power systems of continental Europe are considered. There are made the analysis of the current state and development of the infrastructure for the Baltic States electric systems, the development of electricity trade between the Baltic States and continental Europe, the problems of shortage and increase of base capacity in the region. The characteristics of the energy and climate national plans published by the Baltic States are given, which consider their intentions to develop renewable energy production for the period up to 2030, which provide for a significant increase in electricity production due to wind farms. The possibilities of reducing the risks of power supply reliability to consumers when there is insufficient balance of supply and demand to maintain the power balance are considered.
{"title":"Implementation of Integration Problem for Baltic Energy Systems into Continental Europe Energy","authors":"A. Mahņitko, T. Lomane, I. Zicmane, Timurs Kuzņecovs, Jurijs Silinevics","doi":"10.1109/RTUCON51174.2020.9316596","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316596","url":null,"abstract":"With the restoration of the Baltic States independence, they faced problems both of a political and economic nature. First of all, these problems were caused by the need to strengthen the energy independence of the Baltic States, since historically its power systems worked in synchronous mode with the United power system of Russia, depending on its mode of operation. It was the Baltic States' desire to eliminate energy dependence on a single energy supplier that determined their desire to integrate their transmission networks into the electrical system of continental Europe. The solution to this problem allows the Baltic States to strengthen their energy independence and become a full participant in the electricity market of continental Europe. Aspects of integration of the Baltic power systems with the power systems of continental Europe are considered. There are made the analysis of the current state and development of the infrastructure for the Baltic States electric systems, the development of electricity trade between the Baltic States and continental Europe, the problems of shortage and increase of base capacity in the region. The characteristics of the energy and climate national plans published by the Baltic States are given, which consider their intentions to develop renewable energy production for the period up to 2030, which provide for a significant increase in electricity production due to wind farms. The possibilities of reducing the risks of power supply reliability to consumers when there is insufficient balance of supply and demand to maintain the power balance are considered.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130342981","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/RTUCON51174.2020.9316606
K. Gulbis, U. Brakanskis, E. Kamoliņš, J. Zarembo
A calculation algorithm is proposed, with the help of which it is possible to calculate the parameters of Synchronous Reluctance Machine (SynRM) and to construct motor characteristics, considering the cross magnetic saturation effect. The algorithm was designed to make it as easy as possible for the reader to use it during the design phase of a reluctance machine. At the end of the article, the application of the algorithm in the process of characteristics calculation is shown. The algorithm applies to an AC, rotating magnetic field machine, without active elements in the rotor.
{"title":"Parameter Calculation Method of Synchronous Reluctance Motor Including Cross Magnetic Saturation","authors":"K. Gulbis, U. Brakanskis, E. Kamoliņš, J. Zarembo","doi":"10.1109/RTUCON51174.2020.9316606","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316606","url":null,"abstract":"A calculation algorithm is proposed, with the help of which it is possible to calculate the parameters of Synchronous Reluctance Machine (SynRM) and to construct motor characteristics, considering the cross magnetic saturation effect. The algorithm was designed to make it as easy as possible for the reader to use it during the design phase of a reluctance machine. At the end of the article, the application of the algorithm in the process of characteristics calculation is shown. The algorithm applies to an AC, rotating magnetic field machine, without active elements in the rotor.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134260322","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/RTUCON51174.2020.9316557
Alberts Serebrjakovs, Oleg Belavin, Deniss Brodņevs
The purpose of this manuscript is to present in visual form the influence of the parameters and profiles of the rotor teeth on the magnitude and shape of the armature EMF of the inductor alternator. The results are given in conditional units, which allows to undertake a comparative analysis without considering the implementation of a particular alternator. The presented results greatly simplify the process of selecting the parameters of the tooth zone and the profiles of the teeth of the rotor in the design process of the inductor alternator in order to achieve the objectives.
{"title":"The Influence of the Tooth Zone Parameters on the Characteristics of Inductor Alternators","authors":"Alberts Serebrjakovs, Oleg Belavin, Deniss Brodņevs","doi":"10.1109/RTUCON51174.2020.9316557","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316557","url":null,"abstract":"The purpose of this manuscript is to present in visual form the influence of the parameters and profiles of the rotor teeth on the magnitude and shape of the armature EMF of the inductor alternator. The results are given in conditional units, which allows to undertake a comparative analysis without considering the implementation of a particular alternator. The presented results greatly simplify the process of selecting the parameters of the tooth zone and the profiles of the teeth of the rotor in the design process of the inductor alternator in order to achieve the objectives.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132231523","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/RTUCON51174.2020.9316560
D. Rusovs, S. Jaundālders, P. Stanka
The elspot price sharp variation in electrical grid should be considered as opportunity for district heating network sources. Renewable cogeneration power plant can integrate thermal energy storage by implementation of two elements: heat pumps and secondary thermal engine like Organic Rankin Cycle turbine. The analysis of statistic data for elspot price and heat consumption for heating clearly reveals free room for application of electrical energy export/import for improvement of total biomass energy source. The concept of Levelized Cost of Storage together with estimation of round-trip-efficiency are used to evaluate relation between main storage parameter: size and lifetime of system to get best possible combination of operating parameters.
{"title":"PUMPED THERMAL ELECTRICITY STORAGE INTEGRATION IN DISTRICT HEATING SYSTEMS","authors":"D. Rusovs, S. Jaundālders, P. Stanka","doi":"10.1109/RTUCON51174.2020.9316560","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316560","url":null,"abstract":"The elspot price sharp variation in electrical grid should be considered as opportunity for district heating network sources. Renewable cogeneration power plant can integrate thermal energy storage by implementation of two elements: heat pumps and secondary thermal engine like Organic Rankin Cycle turbine. The analysis of statistic data for elspot price and heat consumption for heating clearly reveals free room for application of electrical energy export/import for improvement of total biomass energy source. The concept of Levelized Cost of Storage together with estimation of round-trip-efficiency are used to evaluate relation between main storage parameter: size and lifetime of system to get best possible combination of operating parameters.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132520614","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/RTUCON51174.2020.9316578
Ģ. Staņa, V. Brazis
The paper describes the method of performing simulations of the movement of electric public transport connected to overhead contact line by considering transmission losses and their compensation. In frames of the method, the transmission resistance-imitating resistors are not applied but the transmission loss compensation current and overhead line voltage drop are calculated mathematically, thus obtaining corresponding results. To calculate the mentioned parameters, the corresponding quadratic equations were derived and the root of the correct solution for each quadratic equation was determined, also analyzing in detail the essence of the second root and its possible application.
{"title":"Mathematical Calculation of Power Transmission Related Parameters in Simulations of Overhead Grid-Connected Electric Public Transport Motion","authors":"Ģ. Staņa, V. Brazis","doi":"10.1109/RTUCON51174.2020.9316578","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316578","url":null,"abstract":"The paper describes the method of performing simulations of the movement of electric public transport connected to overhead contact line by considering transmission losses and their compensation. In frames of the method, the transmission resistance-imitating resistors are not applied but the transmission loss compensation current and overhead line voltage drop are calculated mathematically, thus obtaining corresponding results. To calculate the mentioned parameters, the corresponding quadratic equations were derived and the root of the correct solution for each quadratic equation was determined, also analyzing in detail the essence of the second root and its possible application.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130147210","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/RTUCON51174.2020.9316570
D. Stepins, Lalithambica Akunuri, A. Subbarao, J. Zakis
Being switch-mode in nature, wireless power transfer systems (WPT) emit significant conducted electromagnetic emissions (EME). In this paper for the first time multi switching frequency scheme is applied to closed-loop WPT systems for reduction of conducted EME. In this method inductive resonant WPT system operates at different discrete switching frequencies sequentially. The effect of the multi switching frequency scheme on main performance characteristics of inductive-resonant wireless battery charger operating in constant current mode is analyzed by using simulations. Performance characteristics of the WPT system with the multi switching frequency scheme are compared with that of WPT system without modulations and with classical switching frequency modulation. It is shown that wireless battery charger with the multi switching frequency scheme exhibits performance similar to performance of wireless battery charger with classical switching frequency modulation but complexity of control is lower.
{"title":"Reduction of Electromagnetic Emissions Generated by Inductive Resonant WPT Systems Using Multi-Switching-Frequency-Based Method","authors":"D. Stepins, Lalithambica Akunuri, A. Subbarao, J. Zakis","doi":"10.1109/RTUCON51174.2020.9316570","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316570","url":null,"abstract":"Being switch-mode in nature, wireless power transfer systems (WPT) emit significant conducted electromagnetic emissions (EME). In this paper for the first time multi switching frequency scheme is applied to closed-loop WPT systems for reduction of conducted EME. In this method inductive resonant WPT system operates at different discrete switching frequencies sequentially. The effect of the multi switching frequency scheme on main performance characteristics of inductive-resonant wireless battery charger operating in constant current mode is analyzed by using simulations. Performance characteristics of the WPT system with the multi switching frequency scheme are compared with that of WPT system without modulations and with classical switching frequency modulation. It is shown that wireless battery charger with the multi switching frequency scheme exhibits performance similar to performance of wireless battery charger with classical switching frequency modulation but complexity of control is lower.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114599880","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/RTUCON51174.2020.9316571
R. Lazdins, A. Mutule
In this paper we describe how the development of an operational algorithm for a natural gas boiler and heat pump with a photovoltaics panel can provide more efficient and cost-effective heat supply for a building, thus reducing emissions and promoting economic energy savings for the consumer. Our developed operational algorithm is able to determine the optimal ON and OFF command for the heat pump and natural gas boiler to supply the building with heat energy as efficiently and economically as possible in the case of a dynamic electricity tariff and installed PV panel, as well as to determine imported electricity and natural gas costs from existing energy infrastructure in every hour of the day.
{"title":"Operational Algorithm for Natural Gas Boiler and Heat Pump System Optimization with PV Panel","authors":"R. Lazdins, A. Mutule","doi":"10.1109/RTUCON51174.2020.9316571","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316571","url":null,"abstract":"In this paper we describe how the development of an operational algorithm for a natural gas boiler and heat pump with a photovoltaics panel can provide more efficient and cost-effective heat supply for a building, thus reducing emissions and promoting economic energy savings for the consumer. Our developed operational algorithm is able to determine the optimal ON and OFF command for the heat pump and natural gas boiler to supply the building with heat energy as efficiently and economically as possible in the case of a dynamic electricity tariff and installed PV panel, as well as to determine imported electricity and natural gas costs from existing energy infrastructure in every hour of the day.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116423519","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/RTUCON51174.2020.9316594
N. Kunicina, A. Zabasta, A. Patlins, I. Bilić, Jānis Pekša
The development of infrastructure and supporting process for creating of prototypes for the future commercialization is significant task. The design of the prototypes is a subject of innovation management. It is also a subject of this paper and new study course. This course focuses on the integration of the marketing, design and manufacturing functions of the company in order to create a new product/service. The target of the course: to develop creative thinking for undergraduate students; to ensure students with a set of tools and methods for product design and development; as well as to improve student's skills and competences in a new product planning/development to apply this in practice. The paper is addressed for all level of students and developers of prototypes of electromechanical devices, automotive control schemes, motion control solutions, as well as a high level of automated infrastructure management technologies. The innovation management approach is good for all level of students and developers of prototypes of electromechanical devices, automotive control schemes, motion control solutions, as well as a high level of automated infrastructure management technologies. The involvement the students in the idea development process through individual contribution and a group common work. The students presented their ideas as the pitch presentation at the end of the course.
{"title":"What a prototype is: the first step for commercialization of scientific ideas","authors":"N. Kunicina, A. Zabasta, A. Patlins, I. Bilić, Jānis Pekša","doi":"10.1109/RTUCON51174.2020.9316594","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316594","url":null,"abstract":"The development of infrastructure and supporting process for creating of prototypes for the future commercialization is significant task. The design of the prototypes is a subject of innovation management. It is also a subject of this paper and new study course. This course focuses on the integration of the marketing, design and manufacturing functions of the company in order to create a new product/service. The target of the course: to develop creative thinking for undergraduate students; to ensure students with a set of tools and methods for product design and development; as well as to improve student's skills and competences in a new product planning/development to apply this in practice. The paper is addressed for all level of students and developers of prototypes of electromechanical devices, automotive control schemes, motion control solutions, as well as a high level of automated infrastructure management technologies. The innovation management approach is good for all level of students and developers of prototypes of electromechanical devices, automotive control schemes, motion control solutions, as well as a high level of automated infrastructure management technologies. The involvement the students in the idea development process through individual contribution and a group common work. The students presented their ideas as the pitch presentation at the end of the course.","PeriodicalId":332414,"journal":{"name":"2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121882644","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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