Pub Date : 2016-03-17DOI: 10.1109/ICEES.2016.7510592
Pankaj Kumar, A. Dahiya
Multi-level (ML) converters, now a day's seems to be one of the finest solutions for the DC-to-AC power conversion in the high power high-voltage applications like HVDC transmission system as well as in medium power medium-voltage applications such as renewable energy system. ML converters uses at least three or more voltage levels (steps) in order to modulate the output ac voltage, which leads to the reduction in the voltage distortion in the power system. For the medium power applications, we have the topologies like cascaded H-Bridge, diode-clamped, flying-capacitor type etc., but in the high power applications, all of these suffers from a common problem of high switching losses, requires devices with high switching capability like MOSFETs, IGBTs, GTOs. In this paper two simulink models of the conventional VSI with their firing circuits are presented and a comparison of the conventional VSI (with a single DC energy source) for the different possible conduction angles of the thyristors is done with the help of FFT tool in MATLAB. Finally the optimization of the thyristors conduction angle for the least possible THD value is proposed by the tabulation method and it is verified that for a conventional VSI, the THD value can also be reduced by varying conduction angle of thyristors to a particular value.
{"title":"A comparison in THD values of conventional 3-phase VSI with different conduction angles of thyristors","authors":"Pankaj Kumar, A. Dahiya","doi":"10.1109/ICEES.2016.7510592","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510592","url":null,"abstract":"Multi-level (ML) converters, now a day's seems to be one of the finest solutions for the DC-to-AC power conversion in the high power high-voltage applications like HVDC transmission system as well as in medium power medium-voltage applications such as renewable energy system. ML converters uses at least three or more voltage levels (steps) in order to modulate the output ac voltage, which leads to the reduction in the voltage distortion in the power system. For the medium power applications, we have the topologies like cascaded H-Bridge, diode-clamped, flying-capacitor type etc., but in the high power applications, all of these suffers from a common problem of high switching losses, requires devices with high switching capability like MOSFETs, IGBTs, GTOs. In this paper two simulink models of the conventional VSI with their firing circuits are presented and a comparison of the conventional VSI (with a single DC energy source) for the different possible conduction angles of the thyristors is done with the help of FFT tool in MATLAB. Finally the optimization of the thyristors conduction angle for the least possible THD value is proposed by the tabulation method and it is verified that for a conventional VSI, the THD value can also be reduced by varying conduction angle of thyristors to a particular value.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129036037","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 : 2016-03-17DOI: 10.1109/ICEES.2016.7510623
S. Manikandan, S. Sasitharan, J. Rao, V. Moorthy
This paper describes a discrete particle swarm optimization (DPSO) based solution procedure for selection of conductor in radial distribution system (RDS) so as to minimize the cost of energy benefit. The objective function is formulated to select optimal size of conductor for each feeder segment so as to minimize the sum of depreciation on capital investment and cost of energy loss subjected to the feeder voltage and maximum current carrying capacity and then proposed algorithm is employed to achieve the objective. The performance of the proposed approach is illustrated on 26 and 33 node RDS. The results have obtained by the proposed technique are compared with the other techniques listed in the literature. The results demonstrate that the DPSO algorithm is feasible and efficient for solving optimal selection of conductor problem.
{"title":"Analysis of optimal conductor selection for radial distribution systems using DPSO","authors":"S. Manikandan, S. Sasitharan, J. Rao, V. Moorthy","doi":"10.1109/ICEES.2016.7510623","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510623","url":null,"abstract":"This paper describes a discrete particle swarm optimization (DPSO) based solution procedure for selection of conductor in radial distribution system (RDS) so as to minimize the cost of energy benefit. The objective function is formulated to select optimal size of conductor for each feeder segment so as to minimize the sum of depreciation on capital investment and cost of energy loss subjected to the feeder voltage and maximum current carrying capacity and then proposed algorithm is employed to achieve the objective. The performance of the proposed approach is illustrated on 26 and 33 node RDS. The results have obtained by the proposed technique are compared with the other techniques listed in the literature. The results demonstrate that the DPSO algorithm is feasible and efficient for solving optimal selection of conductor problem.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133250016","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 : 2016-03-17DOI: 10.1109/ICEES.2016.7510649
A. Nair, Chantrabose, Arunraj, Murugan, V. Kirubakaran
Even though India started commercial solar PV power plants, the efficiency of the PV system has not been raided. Many investigations have been made material design and characterization. But the major influencing parameters for the solar PV output is environmental parameters like dust, temperature, air velocity etc. In this project an attempt has been made to increase ambient humidity near the panel to near saturation humidity which leads 12-16 % increase power output. In a huge power plants this device can be put in to use to increase the net power output and reduce the cost.
{"title":"Increasing solar PV output by controlling environmental parameters","authors":"A. Nair, Chantrabose, Arunraj, Murugan, V. Kirubakaran","doi":"10.1109/ICEES.2016.7510649","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510649","url":null,"abstract":"Even though India started commercial solar PV power plants, the efficiency of the PV system has not been raided. Many investigations have been made material design and characterization. But the major influencing parameters for the solar PV output is environmental parameters like dust, temperature, air velocity etc. In this project an attempt has been made to increase ambient humidity near the panel to near saturation humidity which leads 12-16 % increase power output. In a huge power plants this device can be put in to use to increase the net power output and reduce the cost.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132156970","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 : 2016-03-17DOI: 10.1109/ICEES.2016.7510643
B. Kumar, A. Usha
The solar converter for power conversion system is a device designed to perform different operations using a simple circuit. The Converter performs both DC/AC and DC/DC operation. This topology is used to supply power to a system during all times of a day. The Photo-voltaic array is interfaced with the battery and hence used to provide power for the entire day. This work demonstrates the solar converter for power conversion system having PID Controller and 7 Level Inverter. The Total Harmonic Distortion is less when solar converter for power conversion having PI Controller is compared with solar converter for power conversion having PID Controller. Further, the Total Harmonic Distortion reduces for the solar converter for power conversion having PID Controller and 7-level inverter system. In this work, the battery unit is designed using the TTL driver circuit and the inverter is designed using MOSFET switches and IR2110 driver circuit. Also, the gating signals are effectively generated using Peripheral Interface Controller (PIC) microcontroller.
{"title":"Design and development of configurable solar converter system","authors":"B. Kumar, A. Usha","doi":"10.1109/ICEES.2016.7510643","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510643","url":null,"abstract":"The solar converter for power conversion system is a device designed to perform different operations using a simple circuit. The Converter performs both DC/AC and DC/DC operation. This topology is used to supply power to a system during all times of a day. The Photo-voltaic array is interfaced with the battery and hence used to provide power for the entire day. This work demonstrates the solar converter for power conversion system having PID Controller and 7 Level Inverter. The Total Harmonic Distortion is less when solar converter for power conversion having PI Controller is compared with solar converter for power conversion having PID Controller. Further, the Total Harmonic Distortion reduces for the solar converter for power conversion having PID Controller and 7-level inverter system. In this work, the battery unit is designed using the TTL driver circuit and the inverter is designed using MOSFET switches and IR2110 driver circuit. Also, the gating signals are effectively generated using Peripheral Interface Controller (PIC) microcontroller.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"138 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122851902","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 : 2016-03-17DOI: 10.1109/ICEES.2016.7510650
S. Dheeban, V. Kamaraj
Renewable energy resources such as wind and solar are more widely used for power generation. Photovoltaic panels are used to convert solar energy into electrical energy. Solar energy can be used for both stand alone and grid side applications. Grid tied systems are connected to electrical grid and allow residents of building to use solar energy. The photovoltaic system consists of PV panels connected through DC-DC converter and DC-AC inverter to the grid. The IV and PV characteristics of PV panels are used to determine the MPP. The MPPT algorithm used for tracking maximum power is incremental conductance algorithm. In addition to operate at the international standards, three phase PWM inverter with PI controller is used. This paper deals with the grid interaction of 10kW panel and the study of real power flow from the source to the utility grid.
{"title":"Grid integration of 10kW solar panel","authors":"S. Dheeban, V. Kamaraj","doi":"10.1109/ICEES.2016.7510650","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510650","url":null,"abstract":"Renewable energy resources such as wind and solar are more widely used for power generation. Photovoltaic panels are used to convert solar energy into electrical energy. Solar energy can be used for both stand alone and grid side applications. Grid tied systems are connected to electrical grid and allow residents of building to use solar energy. The photovoltaic system consists of PV panels connected through DC-DC converter and DC-AC inverter to the grid. The IV and PV characteristics of PV panels are used to determine the MPP. The MPPT algorithm used for tracking maximum power is incremental conductance algorithm. In addition to operate at the international standards, three phase PWM inverter with PI controller is used. This paper deals with the grid interaction of 10kW panel and the study of real power flow from the source to the utility grid.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126731240","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 : 2016-03-17DOI: 10.1109/ICEES.2016.7510624
Deepu Jose, Mobi Mathew, A. Krishnan
Electrical energy demand of domestic consumers depends on many factors like population, regional development, weather, electricity price, industrialization etc. For those regions having different climatic conditions in a year, it is found that the energy demand depends on prevailing weather. So a study on weather dependency of energy demand would help in accurate load forecasting and maintenance schedules. This paper aims at analyzing the trends in weather dependency in energy demand and monthly load forecasting. Linear and non linear regression models are developed. Multiple linear regression to check the dependency of energy demand on different climatic factors like temperature and relative humidity is developed. Non linear forecast model of Energy consumption as per the variation in the temperature is also developed. Energy consumption details of Attavara area, obtained from Attavar sub-station, is related with weather data obtained from Mangalore Bajpe weather station for the analysis of seasonal demand of energy demand.
{"title":"Weather dependency of electricity demand: A case study in warm humid tropical climate","authors":"Deepu Jose, Mobi Mathew, A. Krishnan","doi":"10.1109/ICEES.2016.7510624","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510624","url":null,"abstract":"Electrical energy demand of domestic consumers depends on many factors like population, regional development, weather, electricity price, industrialization etc. For those regions having different climatic conditions in a year, it is found that the energy demand depends on prevailing weather. So a study on weather dependency of energy demand would help in accurate load forecasting and maintenance schedules. This paper aims at analyzing the trends in weather dependency in energy demand and monthly load forecasting. Linear and non linear regression models are developed. Multiple linear regression to check the dependency of energy demand on different climatic factors like temperature and relative humidity is developed. Non linear forecast model of Energy consumption as per the variation in the temperature is also developed. Energy consumption details of Attavara area, obtained from Attavar sub-station, is related with weather data obtained from Mangalore Bajpe weather station for the analysis of seasonal demand of energy demand.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125076810","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 : 2016-03-17DOI: 10.1109/ICEES.2016.7510635
S. Jeevananthan, K. Gayathri, P. Chandrasekar
AC-AC power conversion has become mandate for modern AC loads due to their standardized supply specifications and unavoidable options of being fed with common AC supply. This paper describes a comprehensive comparison of two competent AC-AC power conversion systems viz. diode bridge front end rectifier-DC link (capacitor)-pulse width modulated voltage source inverter (PWM-VSI) and matrix converter (MC). Though, the survival of VSI based systems largely fuelled by time to time application demanded modifications of PWM strategy, they suffer by poor input side performance, output voltage restriction etc. Highly motivated remedy for this issue is employing MC in AC-AC conversion. The system replacement may only be justified if comprehensive performance comparison of both is studied. Comparison on the basis of harmonic profile, range and controllability of output line voltage, and power factor and harmonic profile of the input current using MATLAB 13-Simulink (Ode 23tb-solver) tool for the RL load is presented.
{"title":"Performance evaluation of competent AC-AC power conversion systems","authors":"S. Jeevananthan, K. Gayathri, P. Chandrasekar","doi":"10.1109/ICEES.2016.7510635","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510635","url":null,"abstract":"AC-AC power conversion has become mandate for modern AC loads due to their standardized supply specifications and unavoidable options of being fed with common AC supply. This paper describes a comprehensive comparison of two competent AC-AC power conversion systems viz. diode bridge front end rectifier-DC link (capacitor)-pulse width modulated voltage source inverter (PWM-VSI) and matrix converter (MC). Though, the survival of VSI based systems largely fuelled by time to time application demanded modifications of PWM strategy, they suffer by poor input side performance, output voltage restriction etc. Highly motivated remedy for this issue is employing MC in AC-AC conversion. The system replacement may only be justified if comprehensive performance comparison of both is studied. Comparison on the basis of harmonic profile, range and controllability of output line voltage, and power factor and harmonic profile of the input current using MATLAB 13-Simulink (Ode 23tb-solver) tool for the RL load is presented.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134129369","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 : 2016-03-17DOI: 10.1109/ICEES.2016.7510621
J. Praveen, B. Rao
Unlike Single objective optimization Multi objective optimization has the major advantage of selecting the control variables with the help of Pareto front. The objectives considered in this paper are cost of generation, transmission losses and L-index. Weighted summation method is taken as the technique for Multi objective Optimization Optimal Power Flow (MOOPF) with and without FACTS. Whereas Particle Swarm Optimization (PSO) is used for optimizing the objective values. The FACTS device used in this paper is Interline power flow controller (IPFC) which is a VSC based multi type FACTS device. The device is placed in IEEE 30-bus test system and the results are compared for two dimensional multi objective optimization optimal power flow with and without FACTS.
{"title":"Multi objective optimization for optimal power flow with IPFC using PSO","authors":"J. Praveen, B. Rao","doi":"10.1109/ICEES.2016.7510621","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510621","url":null,"abstract":"Unlike Single objective optimization Multi objective optimization has the major advantage of selecting the control variables with the help of Pareto front. The objectives considered in this paper are cost of generation, transmission losses and L-index. Weighted summation method is taken as the technique for Multi objective Optimization Optimal Power Flow (MOOPF) with and without FACTS. Whereas Particle Swarm Optimization (PSO) is used for optimizing the objective values. The FACTS device used in this paper is Interline power flow controller (IPFC) which is a VSC based multi type FACTS device. The device is placed in IEEE 30-bus test system and the results are compared for two dimensional multi objective optimization optimal power flow with and without FACTS.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124897727","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 : 2016-03-17DOI: 10.1109/ICEES.2016.7510616
A. Selvam, P. Manikandan
In modern era of power systems, generation, transmission and distribution is well operated and maintained to satisfy the demand and supply management. Various problems are faced every day in all the power system areas. One among the problems faced in all the high voltage electrical equipment's is grounding. Natural grounding is done using charcoal and salt to maintain the less resistance in the grounding pit but the less resistance grounding pit becomes high resistive area due to various reasons like improper maintenance, charcoal and salt getting dissolved in soil after some period of time. In this paper a new method of grounding which uses Flyash and Bentonite is proposed and the performance is been analyzed by various standard methods.
{"title":"Performance analysis of Flyash with Bentonite in grounding pit","authors":"A. Selvam, P. Manikandan","doi":"10.1109/ICEES.2016.7510616","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510616","url":null,"abstract":"In modern era of power systems, generation, transmission and distribution is well operated and maintained to satisfy the demand and supply management. Various problems are faced every day in all the power system areas. One among the problems faced in all the high voltage electrical equipment's is grounding. Natural grounding is done using charcoal and salt to maintain the less resistance in the grounding pit but the less resistance grounding pit becomes high resistive area due to various reasons like improper maintenance, charcoal and salt getting dissolved in soil after some period of time. In this paper a new method of grounding which uses Flyash and Bentonite is proposed and the performance is been analyzed by various standard methods.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129935832","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 : 2016-03-17DOI: 10.1109/ICEES.2016.7510638
K. Shrinath, S. Paramasivam, C. S. Bhavani
This paper presents different types of rectifier schemes such as 12, 18, 24 and 36 for grid utility interface with low power variable frequency drives (VFD). To demonstrate Ithd at a Point of Common Coupling (PCC), system level modelsare developed for different rectifier systems. The configurations are simulated and implemented using MATLAB-Simulink. The study involves comparison of different rectifier schemes with respectiveIEEE-519(2014) standard for various short circuit ratios (SCR).A detailed harmonic analysis of different configurations is made and complete results are presented. A comprehensive study on different rectifier schemes is made and their overall performance is studied and discussed.
{"title":"Modelling, simulation and analysis on various front-end rectifiers schemes for PMSM motor drives","authors":"K. Shrinath, S. Paramasivam, C. S. Bhavani","doi":"10.1109/ICEES.2016.7510638","DOIUrl":"https://doi.org/10.1109/ICEES.2016.7510638","url":null,"abstract":"This paper presents different types of rectifier schemes such as 12, 18, 24 and 36 for grid utility interface with low power variable frequency drives (VFD). To demonstrate Ithd at a Point of Common Coupling (PCC), system level modelsare developed for different rectifier systems. The configurations are simulated and implemented using MATLAB-Simulink. The study involves comparison of different rectifier schemes with respectiveIEEE-519(2014) standard for various short circuit ratios (SCR).A detailed harmonic analysis of different configurations is made and complete results are presented. A comprehensive study on different rectifier schemes is made and their overall performance is studied and discussed.","PeriodicalId":308604,"journal":{"name":"2016 3rd International Conference on Electrical Energy Systems (ICEES)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114292662","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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