Pub Date : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316605
J. Caiko, A. Patlins, A. Nurlan, Vladimir Protsenko
nowadays, due to the pandemic, many organizations have switched to remote work via video conferencing, but the complexity of organizing video conferencing arises due to the limited number of participants at the same time, as well as the need for large and fully equipped conference rooms. This may not be a problem for a large enterprise, but for a small and medium-sized business, accessing video conferencing facilities either requires extremely high rents or is completely impossible. The goal of this article is to design and implement an open source video conferencing prototype Jitsi that solves the meeting challenges.
{"title":"Video-conference Communication Platform Based on WebRTC Online meetings","authors":"J. Caiko, A. Patlins, A. Nurlan, Vladimir Protsenko","doi":"10.1109/RTUCON51174.2020.9316605","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316605","url":null,"abstract":"nowadays, due to the pandemic, many organizations have switched to remote work via video conferencing, but the complexity of organizing video conferencing arises due to the limited number of participants at the same time, as well as the need for large and fully equipped conference rooms. This may not be a problem for a large enterprise, but for a small and medium-sized business, accessing video conferencing facilities either requires extremely high rents or is completely impossible. The goal of this article is to design and implement an open source video conferencing prototype Jitsi that solves the meeting challenges.","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":"129493801","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":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":"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/RTUCON51174.2020.9316580
Pavel Gubin, V. Oboskalov, A. Mahņitko, Aleksandrs Gavrilovs
There are a number of ways to solve generating equipment maintenance problem by appliance of deterministic methods as well as heuristic ones. A differential evolution method as a heuristic one seems to be perspective tool for this task. The research demonstrates opportunity to apply differential evolution method to generating equipment maintenance planning problem basing on comparison between the method and directed search ones as well as analysis results of dependence of planning results on evolution method parameters.
{"title":"An Investigation into the Effectiveness of the Differential Evolution Method for Optimal Generating Units Maintenance by EENS Criteria","authors":"Pavel Gubin, V. Oboskalov, A. Mahņitko, Aleksandrs Gavrilovs","doi":"10.1109/RTUCON51174.2020.9316580","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316580","url":null,"abstract":"There are a number of ways to solve generating equipment maintenance problem by appliance of deterministic methods as well as heuristic ones. A differential evolution method as a heuristic one seems to be perspective tool for this task. The research demonstrates opportunity to apply differential evolution method to generating equipment maintenance planning problem basing on comparison between the method and directed search ones as well as analysis results of dependence of planning results on evolution method 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":"121333818","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/RTUCON51174.2020.9316624
O. Karimzada, Y.R. Adullayev
One of the types of the tension control device for winding the coils is a tracking system with levitation screens. The following work examines the features of tracking system with levitation screens. Taking into account the magnetic scattering conductivity and the magnetic induction in the steel and the current of the excitation winding, analytical expressions are obtained for the number of turns of the excitation winding, the thickness of the working air gap, and the dimensions of the magnetic core. A method for determining the optimum values of the working air gap thickness is described.
{"title":"Electromagnetic Calculation of The Tracking System With Levitation Screens","authors":"O. Karimzada, Y.R. Adullayev","doi":"10.1109/RTUCON51174.2020.9316624","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316624","url":null,"abstract":"One of the types of the tension control device for winding the coils is a tracking system with levitation screens. The following work examines the features of tracking system with levitation screens. Taking into account the magnetic scattering conductivity and the magnetic induction in the steel and the current of the excitation winding, analytical expressions are obtained for the number of turns of the excitation winding, the thickness of the working air gap, and the dimensions of the magnetic core. A method for determining the optimum values of the working air gap thickness is described.","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":"122314148","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":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":"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}
Pub Date : 2020-11-05DOI: 10.1109/RTUCON51174.2020.9316586
V. Burenin, J. Zarembo, A. Žiravecka, L. Ribickis
This paper describes created Simulink model of an induction machine laboratory test-bench setup, for testing of electric drives up to 1kV for urban transport. The model takes into account discreteness of the digital signal processor and values of a real induction machine. Both model and test-bench are tested with different loads at a constant speed, and compared to assure accuracy of the model. Experimental results show, that created model could be used to assist design of the control system for traction application.
{"title":"Model of Laboratory Test Bench Setup for Testing Electrical Machines","authors":"V. Burenin, J. Zarembo, A. Žiravecka, L. Ribickis","doi":"10.1109/RTUCON51174.2020.9316586","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316586","url":null,"abstract":"This paper describes created Simulink model of an induction machine laboratory test-bench setup, for testing of electric drives up to 1kV for urban transport. The model takes into account discreteness of the digital signal processor and values of a real induction machine. Both model and test-bench are tested with different loads at a constant speed, and compared to assure accuracy of the model. Experimental results show, that created model could be used to assist design of the control system for traction 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":"116546788","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/RTUCON51174.2020.9316623
Signe Allena-Ozoliņa, Ieva Pakere, D. Jaunzems, A. Blumberga, G. Bažbauers
As climate targets become more critical, an appropriate supportive tools in policy planning are needed. TIMES model is powerful tool for energy scenario analysis allowing assess the impact of potential policy measures. The paper presents the methodology and results for energy sector modelling of Latvia by using TIMES model. To analyse further development of electricity and heating sector, three different scenarios have been compared - reference scenario, which excludes the existing tax policy, baseline scenario which considers the existing policy measures and the scenario which includes different policy measures defined in the National Energy and Climate plan until 2030.
{"title":"Integrated MARKAL-EFOM System (TIMES) Model for Energy Sector Modelling","authors":"Signe Allena-Ozoliņa, Ieva Pakere, D. Jaunzems, A. Blumberga, G. Bažbauers","doi":"10.1109/RTUCON51174.2020.9316623","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316623","url":null,"abstract":"As climate targets become more critical, an appropriate supportive tools in policy planning are needed. TIMES model is powerful tool for energy scenario analysis allowing assess the impact of potential policy measures. The paper presents the methodology and results for energy sector modelling of Latvia by using TIMES model. To analyse further development of electricity and heating sector, three different scenarios have been compared - reference scenario, which excludes the existing tax policy, baseline scenario which considers the existing policy measures and the scenario which includes different policy measures defined in the National Energy and Climate plan until 2030.","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":"133795395","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/RTUCON51174.2020.9316593
A. Gancone, K. Bumbiere, J. Pubule, D. Blumberga
Although European Union has set a target for all Member States that by 2050 the share of renewable energy sources has to achieve at least 55% in gross final energy consumption, it is necessary to assess the conditions under which such a policy is sustainable. The use of biogas in energy sector is one of the possible solutions. Transport sector consumed 30.1 % of the energy resources (2018) in Latvia and given that it is the largest and the agricultural sector is the second largest sector responsible for GHG emissions in Latvia, this study uses Latvian data to examine the optimal solutions for increasing the share of renewable energy in the transport sector, balancing it with a sustainable strategy for the agricultural sector. This study focuses on the impacts and effectivity of biogas application in autotransport. The study examined the case of biogas used in cogeneration plant and electricity produced in cogeneration for autotransport versus the conversion of biogas into biomethane for the use of autotransport. The results obtained not only suggest the most efficient solutions for the use of biogas in the future, but also indicate environmental, economic and social aspects.
{"title":"Sustainable biogas application in energy sector","authors":"A. Gancone, K. Bumbiere, J. Pubule, D. Blumberga","doi":"10.1109/RTUCON51174.2020.9316593","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316593","url":null,"abstract":"Although European Union has set a target for all Member States that by 2050 the share of renewable energy sources has to achieve at least 55% in gross final energy consumption, it is necessary to assess the conditions under which such a policy is sustainable. The use of biogas in energy sector is one of the possible solutions. Transport sector consumed 30.1 % of the energy resources (2018) in Latvia and given that it is the largest and the agricultural sector is the second largest sector responsible for GHG emissions in Latvia, this study uses Latvian data to examine the optimal solutions for increasing the share of renewable energy in the transport sector, balancing it with a sustainable strategy for the agricultural sector. This study focuses on the impacts and effectivity of biogas application in autotransport. The study examined the case of biogas used in cogeneration plant and electricity produced in cogeneration for autotransport versus the conversion of biogas into biomethane for the use of autotransport. The results obtained not only suggest the most efficient solutions for the use of biogas in the future, but also indicate environmental, economic and social aspects.","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":"124079504","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/RTUCON51174.2020.9316573
N. Kunicina, A. Zabasta, O. Krumins, A. Romānovs, A. Patlins
The risks of information security threats in conditions of rapidly increasing use of information and communication technologies in society, economy and public administration have led to the need for a significant increase of information reliability. The efficient education for international career building of young engineers in the technical aspects of Cyber security is discussed in this article. The mission of such engineers is the development of technical assets, mechanisms, electronic devices and systems, as well as integration legacy solutions and reengineering of systems, taking into account protection of information assets. It has become one of the fastest growing information technology in industries today, mainly due to two trends: (1) exponential growth of data from business systems and security sensors to protect this business; (2) lack of qualified cyber security staff to analyze and respond to incidents related to these data. The market analysis on the international and national levels, chows, that the number of vacancies in area is growing, for example the number of specialists required by CERT.LV only is around 200, and they estimate that the number of employees required by private companies is several hundreds on national level. Developed countries laws require companies to designate a qualified person responsible for IT security issues and the development and maintenance of technological solutions. The task of a cyber security specialist in companies and different organizations is to manage security solutions, consult users and provide expertise not only engineering background, but also background in IT security issues. Implementation of these tasks requires a wide range of multidisciplinary knowledge, including computer networking, software, integrated systems, critical infrastructure security and security management.
{"title":"Cybersecurity Curricula Recommendations Development for Technical Background and Engineering Skills in International Dimension","authors":"N. Kunicina, A. Zabasta, O. Krumins, A. Romānovs, A. Patlins","doi":"10.1109/RTUCON51174.2020.9316573","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316573","url":null,"abstract":"The risks of information security threats in conditions of rapidly increasing use of information and communication technologies in society, economy and public administration have led to the need for a significant increase of information reliability. The efficient education for international career building of young engineers in the technical aspects of Cyber security is discussed in this article. The mission of such engineers is the development of technical assets, mechanisms, electronic devices and systems, as well as integration legacy solutions and reengineering of systems, taking into account protection of information assets. It has become one of the fastest growing information technology in industries today, mainly due to two trends: (1) exponential growth of data from business systems and security sensors to protect this business; (2) lack of qualified cyber security staff to analyze and respond to incidents related to these data. The market analysis on the international and national levels, chows, that the number of vacancies in area is growing, for example the number of specialists required by CERT.LV only is around 200, and they estimate that the number of employees required by private companies is several hundreds on national level. Developed countries laws require companies to designate a qualified person responsible for IT security issues and the development and maintenance of technological solutions. The task of a cyber security specialist in companies and different organizations is to manage security solutions, consult users and provide expertise not only engineering background, but also background in IT security issues. Implementation of these tasks requires a wide range of multidisciplinary knowledge, including computer networking, software, integrated systems, critical infrastructure security and security management.","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":"128649874","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/RTUCON51174.2020.9316487
Toomas Erik Anijärv, Noman Shabbir, L. Kütt, M. N. Iqbal
Electrical outages cause economical loss but in many cases lead also to broken devices. Similarly, repeated voltage fluctuation may result in overstress of the components of the grid which leads to electrical failure. Before any electrical fault, usually, some smaller-scale anomalies occur in load current or voltage. These anomalies can usually be detected from measured quantities by using the Fourier transform and by analyzing voltage changes indicated as additional frequency components. However, the noise present in the real signal makes this analysis less accurate. Therefore, a wavelet transform based denoising method is proposed here along with Fourier transform to overcome this problem. In this paper, a discussion on the options for real-time diagnostics of an electrical grid is presented. The methods are compared and analyzed to assess the reliability of the proposed method. The anomalies observed are linked to unexpected voltage RMS values which correspond to variations in frequency domain components.
{"title":"Requirements to Data Acquisition and Signal Analysis for Electrical Grid Condition Monitoring","authors":"Toomas Erik Anijärv, Noman Shabbir, L. Kütt, M. N. Iqbal","doi":"10.1109/RTUCON51174.2020.9316487","DOIUrl":"https://doi.org/10.1109/RTUCON51174.2020.9316487","url":null,"abstract":"Electrical outages cause economical loss but in many cases lead also to broken devices. Similarly, repeated voltage fluctuation may result in overstress of the components of the grid which leads to electrical failure. Before any electrical fault, usually, some smaller-scale anomalies occur in load current or voltage. These anomalies can usually be detected from measured quantities by using the Fourier transform and by analyzing voltage changes indicated as additional frequency components. However, the noise present in the real signal makes this analysis less accurate. Therefore, a wavelet transform based denoising method is proposed here along with Fourier transform to overcome this problem. In this paper, a discussion on the options for real-time diagnostics of an electrical grid is presented. The methods are compared and analyzed to assess the reliability of the proposed method. The anomalies observed are linked to unexpected voltage RMS values which correspond to variations in frequency domain components.","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":"125996393","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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