Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115826
V. Bist, Bhim Singh
This work presents a sensorless brushless DC motor (BLDCM) drive with power factor correction (PFC). The speed control of BLDCM is achieved by varying the DC bus voltage of the voltage source inverter (VSI) feeding BLDCM. The BLDCM is electronically commutated using a VSI operating at low frequency switching for reducing the switching losses in VSI. A canonical switching cell (CSC) converter is used for varying the DC bus voltage of VSI. This CSC converter is operated in discontinuous inductor current mode (DICM) for achieving a power factor correction (PFC) inherently without any sensing requirement. The rotor position sensors are eliminated by using sensorless control of BLDCM. Hence, a sensorless BLDCM drive is developed as a cost effective solution for low power applications. Its performance is evaluated on a developed prototype at various speeds with unity power factor (UPF) at AC mains.
{"title":"Power factor correction in sensorless BLDC motor drive","authors":"V. Bist, Bhim Singh","doi":"10.1109/IICPE.2014.7115826","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115826","url":null,"abstract":"This work presents a sensorless brushless DC motor (BLDCM) drive with power factor correction (PFC). The speed control of BLDCM is achieved by varying the DC bus voltage of the voltage source inverter (VSI) feeding BLDCM. The BLDCM is electronically commutated using a VSI operating at low frequency switching for reducing the switching losses in VSI. A canonical switching cell (CSC) converter is used for varying the DC bus voltage of VSI. This CSC converter is operated in discontinuous inductor current mode (DICM) for achieving a power factor correction (PFC) inherently without any sensing requirement. The rotor position sensors are eliminated by using sensorless control of BLDCM. Hence, a sensorless BLDCM drive is developed as a cost effective solution for low power applications. Its performance is evaluated on a developed prototype at various speeds with unity power factor (UPF) at AC mains.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121572556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115861
M. Veerachary
In this paper a zero voltage transition low source ripple current fifth order boost converter is proposed, which offers several advantages over conventional and higher-order boost converters. This converter provides higher voltage gain moderate duty ratios. The zero voltage transition auxiliary circuit is incorporated into the circuit to provide further advantages in terms of reduction of switching losses for nearly all the switching devices. Modes of operations are identified, and then steady-state analysis is presented for design purpose. In order to verify the zero-voltage switching, soft-switching, performance of this converter simulation is carried out in PSIM. To further test the advantage provided by this converter, over hard switched converters, a comparative analysis is carried out in simulation and experiment at various loading conditions. The converter performance is predetermined for a 24 to 48 V, 25 W prototype in simulation and then compared with experimental results. Experimental measurements are in close agreement with analytical predictions.
{"title":"Design and analysis of zero-voltage transition fifth-order boost converter","authors":"M. Veerachary","doi":"10.1109/IICPE.2014.7115861","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115861","url":null,"abstract":"In this paper a zero voltage transition low source ripple current fifth order boost converter is proposed, which offers several advantages over conventional and higher-order boost converters. This converter provides higher voltage gain moderate duty ratios. The zero voltage transition auxiliary circuit is incorporated into the circuit to provide further advantages in terms of reduction of switching losses for nearly all the switching devices. Modes of operations are identified, and then steady-state analysis is presented for design purpose. In order to verify the zero-voltage switching, soft-switching, performance of this converter simulation is carried out in PSIM. To further test the advantage provided by this converter, over hard switched converters, a comparative analysis is carried out in simulation and experiment at various loading conditions. The converter performance is predetermined for a 24 to 48 V, 25 W prototype in simulation and then compared with experimental results. Experimental measurements are in close agreement with analytical predictions.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126253881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115774
N. K. Swami Naidu, Bhim Singh
This paper presents an implementation of Doubly Fed Induction Generator (DFIG) based Standalone Wind Energy Conversion System (SWECS). Control algorithms of both Rotor Side Converter (RSC) and Load Side Converter (LSC) are presented for maintaining voltage and frequency for variable speed DFIG based SWECS. A prototype of this proposed DFIG based SWECS is developed using a DSP (Digital Signal Processor-dSPACE DS1103). This proposed DFIG is tested under nonlinear and dynamic loads. Dynamic performance of this proposed VFC is tested at unbalanced load, sudden change in loads and also for variable wind speeds.
{"title":"Experimental implementation of Doubly Fed Induction Generator based Standalone Wind Energy Conversion System","authors":"N. K. Swami Naidu, Bhim Singh","doi":"10.1109/IICPE.2014.7115774","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115774","url":null,"abstract":"This paper presents an implementation of Doubly Fed Induction Generator (DFIG) based Standalone Wind Energy Conversion System (SWECS). Control algorithms of both Rotor Side Converter (RSC) and Load Side Converter (LSC) are presented for maintaining voltage and frequency for variable speed DFIG based SWECS. A prototype of this proposed DFIG based SWECS is developed using a DSP (Digital Signal Processor-dSPACE DS1103). This proposed DFIG is tested under nonlinear and dynamic loads. Dynamic performance of this proposed VFC is tested at unbalanced load, sudden change in loads and also for variable wind speeds.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"10 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113989399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115753
Shikha Singh, Bhim Singh, G. Bhuvaneswari
This paper envisages to design, analyze and assess the performance of a new Power Factor Corrected (PFC) bridgeless converter based power supply for Personal Computers. The proposed Switched Mode Power Supply is a combination of a bridgeless converter operating as a PFC at the front end and an isolated converter at the back end for obtaining multiple dc output voltages. The proposed configuration eliminates the diode bridge at the front end thereby offering low conduction losses and high power quality in line with IEC-61000 standard norms. The front end converter offers fast dynamic response compounded with good output voltage regulation where the output is characterized by a low 100 Hz ripple. The performance of the proposed power supply is analyzed to validate the design and its improved performance is demonstrated by means of simulations.
{"title":"Improved power quality SMPS for computers using bridgeless PFC converter at front end","authors":"Shikha Singh, Bhim Singh, G. Bhuvaneswari","doi":"10.1109/IICPE.2014.7115753","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115753","url":null,"abstract":"This paper envisages to design, analyze and assess the performance of a new Power Factor Corrected (PFC) bridgeless converter based power supply for Personal Computers. The proposed Switched Mode Power Supply is a combination of a bridgeless converter operating as a PFC at the front end and an isolated converter at the back end for obtaining multiple dc output voltages. The proposed configuration eliminates the diode bridge at the front end thereby offering low conduction losses and high power quality in line with IEC-61000 standard norms. The front end converter offers fast dynamic response compounded with good output voltage regulation where the output is characterized by a low 100 Hz ripple. The performance of the proposed power supply is analyzed to validate the design and its improved performance is demonstrated by means of simulations.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121583449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115803
P. Jain, R. Bhakar, S. N. Singh
In Day-Ahead (DA) electricity markets, Generating Companies (Gencos) aim to maximize their profit by bidding optimally, under incomplete information of the competitors. This paper develops an optimal bidding strategy for 24 hourly markets over a day, for a multi-unit thermal Genco. Different fuel type units are considered and the problem has been developed for maximization of cumulative profit. Uncertain rivals' bidding behavior is modeled using normal distribution function, and the bidding strategy is formulated as a stochastic optimization problem. Monte Carlo method with a novel hybrid of Differential Evolution (DE) and Biogeography Based Optimization (BBO) (DE/BBO) is proposed as solution approach. The simulation results present the effect of operating constraints and fuel price on the bidding nature of different fuel units. The performance analysis of DE/BBO with GA and its constituents, DE and BBO, proves it to be an efficient tool for this complex problem.
{"title":"Hybrid Differential Evolution with BBO for Genco's multi-hourly strategic bidding","authors":"P. Jain, R. Bhakar, S. N. Singh","doi":"10.1109/IICPE.2014.7115803","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115803","url":null,"abstract":"In Day-Ahead (DA) electricity markets, Generating Companies (Gencos) aim to maximize their profit by bidding optimally, under incomplete information of the competitors. This paper develops an optimal bidding strategy for 24 hourly markets over a day, for a multi-unit thermal Genco. Different fuel type units are considered and the problem has been developed for maximization of cumulative profit. Uncertain rivals' bidding behavior is modeled using normal distribution function, and the bidding strategy is formulated as a stochastic optimization problem. Monte Carlo method with a novel hybrid of Differential Evolution (DE) and Biogeography Based Optimization (BBO) (DE/BBO) is proposed as solution approach. The simulation results present the effect of operating constraints and fuel price on the bidding nature of different fuel units. The performance analysis of DE/BBO with GA and its constituents, DE and BBO, proves it to be an efficient tool for this complex problem.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122825659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115798
S. Chauhan, Malik Sameeullah, R. Dahiya
Wind energy is gaining increasing importance throughout the world. With the advancement of variable speed drive design and control of wind energy systems, the efficiency and the energy capture capacity of the energy conversion system is also improved. For renewable energy system, Maximum Power Point Tracking (MPPT) plays a vital role for efficient conversion of energy. The MPPT strategy is used to control the rotor speed by adjusting electromagnetic torque and maximize the electrical output power of the generator. In this paper, three different control schemes are discussed and implemented in Matlab Simulink environment. Simulink result is used to compare the performance of 5.7KW wind turbine under different control schemes.
{"title":"Maximum Power Point Tracking scheme for variable speed wind generator","authors":"S. Chauhan, Malik Sameeullah, R. Dahiya","doi":"10.1109/IICPE.2014.7115798","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115798","url":null,"abstract":"Wind energy is gaining increasing importance throughout the world. With the advancement of variable speed drive design and control of wind energy systems, the efficiency and the energy capture capacity of the energy conversion system is also improved. For renewable energy system, Maximum Power Point Tracking (MPPT) plays a vital role for efficient conversion of energy. The MPPT strategy is used to control the rotor speed by adjusting electromagnetic torque and maximize the electrical output power of the generator. In this paper, three different control schemes are discussed and implemented in Matlab Simulink environment. Simulink result is used to compare the performance of 5.7KW wind turbine under different control schemes.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125227035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115752
P. Nayar, Bhim Singh, S. Mishra
An application of artificial intelligence is presented in solving power quality problems using a distribution static compensator (DSTATCOM) in the distribution system involving lagging pf loads. A set of three nonlinear neurons is used to obtain the three phase compensating currents. Another set of three layered feed-forward neural network controls the compensating currents. The developed model works accurately under varying load conditions and provides good dynamic response to the step changes in the load currents. A real time performance is achieved using SIMULINKR/Sim-powersystem (SPS) toolboxes and simulated results adhere to the IEEE-519 standard for improvement of power quality.
{"title":"Neural network based enhancement of power quality in distribution system","authors":"P. Nayar, Bhim Singh, S. Mishra","doi":"10.1109/IICPE.2014.7115752","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115752","url":null,"abstract":"An application of artificial intelligence is presented in solving power quality problems using a distribution static compensator (DSTATCOM) in the distribution system involving lagging pf loads. A set of three nonlinear neurons is used to obtain the three phase compensating currents. Another set of three layered feed-forward neural network controls the compensating currents. The developed model works accurately under varying load conditions and provides good dynamic response to the step changes in the load currents. A real time performance is achieved using SIMULINKR/Sim-powersystem (SPS) toolboxes and simulated results adhere to the IEEE-519 standard for improvement of power quality.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133313797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115735
Shagufta Khan, S. Bhowmick
This paper demonstrate the modeling and control of the Static Synchronous Compensator (STATCOM) using Newton Raphson Load Flow (NRLF) and Fast Decoupled Load Flow (FDLF) algorithm in MATLAB environment. To reduce the complexity of the program, decoupling method is used. The STATCOM is a shunt FACTS (Flexible AC Transmission System) controller which is used to improve the bus voltage profile. Both models are used in multiple control modes. A fictitious bus is created in both models to connect the STATCOM and to reduce the complexity of the program. The STATCOM is connected via coupling transformer impedance. The switching losses and losses in the coupling transformer are also incorporated in this model. The various case studies are carried out in IEEE 30-bus test network with and without the STATCOM. The results justify the enhancement of power quality for multiple case studies.
{"title":"A study of Static Synchronous Compensator in two power flow models","authors":"Shagufta Khan, S. Bhowmick","doi":"10.1109/IICPE.2014.7115735","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115735","url":null,"abstract":"This paper demonstrate the modeling and control of the Static Synchronous Compensator (STATCOM) using Newton Raphson Load Flow (NRLF) and Fast Decoupled Load Flow (FDLF) algorithm in MATLAB environment. To reduce the complexity of the program, decoupling method is used. The STATCOM is a shunt FACTS (Flexible AC Transmission System) controller which is used to improve the bus voltage profile. Both models are used in multiple control modes. A fictitious bus is created in both models to connect the STATCOM and to reduce the complexity of the program. The STATCOM is connected via coupling transformer impedance. The switching losses and losses in the coupling transformer are also incorporated in this model. The various case studies are carried out in IEEE 30-bus test network with and without the STATCOM. The results justify the enhancement of power quality for multiple case studies.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131005898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115851
Siddharth Varshney, M. Koli, M. Borage, S. Tiwari, A. Thakurta
The paper deals with design, development and reliability prediction of ±10V, ±10A four-quadrant switch mode power supply. One of the application of this power supply is as a corrector electromagnet power supply in particle accelerators. In this power supply, topology used is a full bridge dc-dc chopper with PWM using unipolar voltage switching operating at 50 kHz. The main features of this supply is its ability to reduce the magnitude of output voltage ripple and increasing the frequency of output ripple thus reducing the size of filter and improved switch utilization factor. Another part of this paper predicts the reliability of this power supply using the procedures followed by MIL-HDBK 217F and various areas are suggested to improve the reliability of this power supply. This power supply attained a peak efficiency as high as 81% and predicts mean time between failures of 614084 hours at 40°C.
{"title":"Design, development and reliability analysis of a four-quadrant electromagnet power supply","authors":"Siddharth Varshney, M. Koli, M. Borage, S. Tiwari, A. Thakurta","doi":"10.1109/IICPE.2014.7115851","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115851","url":null,"abstract":"The paper deals with design, development and reliability prediction of ±10V, ±10A four-quadrant switch mode power supply. One of the application of this power supply is as a corrector electromagnet power supply in particle accelerators. In this power supply, topology used is a full bridge dc-dc chopper with PWM using unipolar voltage switching operating at 50 kHz. The main features of this supply is its ability to reduce the magnitude of output voltage ripple and increasing the frequency of output ripple thus reducing the size of filter and improved switch utilization factor. Another part of this paper predicts the reliability of this power supply using the procedures followed by MIL-HDBK 217F and various areas are suggested to improve the reliability of this power supply. This power supply attained a peak efficiency as high as 81% and predicts mean time between failures of 614084 hours at 40°C.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130494772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115741
S. Parashar, S. Dhankhar
In current scenario, renewable energy sources helps to make the environment greener and better. Currently, solar energy is the most available resource of renewable energy. This paper mainly represents the working principle of solar photovoltaic system and way to increase efficiency of the solar system using a method known as the data acquisition system. Data acquisition is a process to monitor changes in system, collect corresponding data and analyze data to make a decision. The data acquisition system has two parts, data acquisition board that contains Microcontroller Kit, ADC, and RS-232 and Zigbee communication modules. Another part is running on a host computer that has a set of software tools as Keil, Proteus, and Visual Basic 6.0 help to analyze and store data. Zigbee communication helps in wireless data transfer without any communication cost. Complete experiment and the result show the data acquisition designed is simple and stable.
{"title":"Increase efficiency of solar photovoltaic system by data acquisition process","authors":"S. Parashar, S. Dhankhar","doi":"10.1109/IICPE.2014.7115741","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115741","url":null,"abstract":"In current scenario, renewable energy sources helps to make the environment greener and better. Currently, solar energy is the most available resource of renewable energy. This paper mainly represents the working principle of solar photovoltaic system and way to increase efficiency of the solar system using a method known as the data acquisition system. Data acquisition is a process to monitor changes in system, collect corresponding data and analyze data to make a decision. The data acquisition system has two parts, data acquisition board that contains Microcontroller Kit, ADC, and RS-232 and Zigbee communication modules. Another part is running on a host computer that has a set of software tools as Keil, Proteus, and Visual Basic 6.0 help to analyze and store data. Zigbee communication helps in wireless data transfer without any communication cost. Complete experiment and the result show the data acquisition designed is simple and stable.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124325405","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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