Pub Date : 2017-10-01DOI: 10.1109/CERA.2017.8343353
Hailiya Ahsan, M. Mufti
This paper proposes a generalized approach of superconducting magnetic energy storage (SMES) modeling, incorporation and control for transient stability analysis of a Western System Coordinating Council (WSCC) 9-bus multi-machine system. The prime agenda of this paper is to assess the frequency, voltage and angular stability of the system when subjected to classified disturbances (faults) at specific distinguished locations. A flexible comprehensive modeling technique is discussed which works on a set of defined differential-algebraic equations(DAEs) and elaborate non-linear parameters of inculcating an SMES in the said system. The non-linearity of SMES control is specially taken into consideration and additionally upper and lower bounds on all power commands and energy exchange are called into effect. Furthermore, the SMES control is developed in such a way that a deliberate SMES energy feedback is taken, so that for a fluent continuous control, the SMES coil energy has a tendency to trace its pre-disturbance nominal value under steady state. The control of the developed system also aims at reducing energy saturations in the system following any abrupt transients. A four-quadrant firing angle scheme is developed and tested.
{"title":"Modeling and simulation of a superconducting magnetic energy storage based multi-machine power system for transient stability study","authors":"Hailiya Ahsan, M. Mufti","doi":"10.1109/CERA.2017.8343353","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343353","url":null,"abstract":"This paper proposes a generalized approach of superconducting magnetic energy storage (SMES) modeling, incorporation and control for transient stability analysis of a Western System Coordinating Council (WSCC) 9-bus multi-machine system. The prime agenda of this paper is to assess the frequency, voltage and angular stability of the system when subjected to classified disturbances (faults) at specific distinguished locations. A flexible comprehensive modeling technique is discussed which works on a set of defined differential-algebraic equations(DAEs) and elaborate non-linear parameters of inculcating an SMES in the said system. The non-linearity of SMES control is specially taken into consideration and additionally upper and lower bounds on all power commands and energy exchange are called into effect. Furthermore, the SMES control is developed in such a way that a deliberate SMES energy feedback is taken, so that for a fluent continuous control, the SMES coil energy has a tendency to trace its pre-disturbance nominal value under steady state. The control of the developed system also aims at reducing energy saturations in the system following any abrupt transients. A four-quadrant firing angle scheme is developed and tested.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116691796","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343370
Pavan Singh Tomar, A. Sharma, K. Hada
The output of solar PV and battery is in the form of DC. Feeding of load from these sources requires conversion from dc to ac or dc to dc. DC microgrids popular for this feature in distributed generation on distribution systems. Energy storage in microgrid ensures electrical saving during no load or off load microgrid. To ensure power flow between DC microgrid and energy storage devices bidirectional dc-dc converter is required. The minimization of losses in dc-dc converter is a big task to improve efficiency. This paper proposes a non-isolated bi-directional DC/DC converter for interfacing DC voltage with energy storage in DC microgrid. The proposed converter is combination of current-fed half bridge boost converter and LCL resonant circuit for soft switching. Boost operation gained by 8 times with the help of front end boost converter, LCL resonant tank and doubler. For buck operation, high side voltage is divided by half with capacitor divider and front-end converter further clamp the voltage. In this paper, the detailed analysis and design is proposed for bidirectional dc-dc converter is done. Soft switching is also implemented by ZVS turn ON of switches and ZCS turn ON/OFF to diode. The performance analysis of proposed converter is done bidirectional power flow with soft switching in MATLAB/Simulink environment.
{"title":"Energy storage in DC microgrid system using non-isolated bidirectional soft-switching DC/DC converter","authors":"Pavan Singh Tomar, A. Sharma, K. Hada","doi":"10.1109/CERA.2017.8343370","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343370","url":null,"abstract":"The output of solar PV and battery is in the form of DC. Feeding of load from these sources requires conversion from dc to ac or dc to dc. DC microgrids popular for this feature in distributed generation on distribution systems. Energy storage in microgrid ensures electrical saving during no load or off load microgrid. To ensure power flow between DC microgrid and energy storage devices bidirectional dc-dc converter is required. The minimization of losses in dc-dc converter is a big task to improve efficiency. This paper proposes a non-isolated bi-directional DC/DC converter for interfacing DC voltage with energy storage in DC microgrid. The proposed converter is combination of current-fed half bridge boost converter and LCL resonant circuit for soft switching. Boost operation gained by 8 times with the help of front end boost converter, LCL resonant tank and doubler. For buck operation, high side voltage is divided by half with capacitor divider and front-end converter further clamp the voltage. In this paper, the detailed analysis and design is proposed for bidirectional dc-dc converter is done. Soft switching is also implemented by ZVS turn ON of switches and ZCS turn ON/OFF to diode. The performance analysis of proposed converter is done bidirectional power flow with soft switching in MATLAB/Simulink environment.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123619936","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343360
S. Prakash, Amit Chatterjee, Jitendra Dhanotia, V. Bhatia
In this paper, we propose a simple system model to generate a temporal sequence of biospeckle patterns which is based on speckle dynamicity by clockwise rotation of a diffuser plate in coherence illumination field. These generated patterns are applied to two popular biospeckle quantification strategies namely inertia moment and absolute value of difference. Performance of both algorithms is assessed and compared by using a number of fixed correlated synthetic speckle sequences.
{"title":"Performance estimation of numerical biospeckle indexing techniques using rotating diffuser based fixed correlation modelling","authors":"S. Prakash, Amit Chatterjee, Jitendra Dhanotia, V. Bhatia","doi":"10.1109/CERA.2017.8343360","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343360","url":null,"abstract":"In this paper, we propose a simple system model to generate a temporal sequence of biospeckle patterns which is based on speckle dynamicity by clockwise rotation of a diffuser plate in coherence illumination field. These generated patterns are applied to two popular biospeckle quantification strategies namely inertia moment and absolute value of difference. Performance of both algorithms is assessed and compared by using a number of fixed correlated synthetic speckle sequences.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131354697","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343368
K. Hada, A. Sharma, Pavan Singh Tomar
This paper extends the concept of q-ZS and introduces a new single-phase improved quasi-ZS ac-ac converter, which is developed by different arrangement of components in conventional Z-source ac-ac converter. In addition to all the merits of the conventional ZS and q-ZS ac-ac power convertors, this proposed improved q-ZS topology have high frequency isolation for safety, low voltage stress, high power density and improved pf. This paper presents the performance analysis of improved q-ZS ac-ac converter with HFTI, which can manage the phase angle of the load voltage as compared to supply voltage even in buck mode, that is very difficult in other ZS ac-ac converters. Simulation results demonstrate the new features of improved quasi-ZS ac-ac converter.
{"title":"Performance analysis of improved q-ZS AC-AC converter with high frequency isolation","authors":"K. Hada, A. Sharma, Pavan Singh Tomar","doi":"10.1109/CERA.2017.8343368","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343368","url":null,"abstract":"This paper extends the concept of q-ZS and introduces a new single-phase improved quasi-ZS ac-ac converter, which is developed by different arrangement of components in conventional Z-source ac-ac converter. In addition to all the merits of the conventional ZS and q-ZS ac-ac power convertors, this proposed improved q-ZS topology have high frequency isolation for safety, low voltage stress, high power density and improved pf. This paper presents the performance analysis of improved q-ZS ac-ac converter with HFTI, which can manage the phase angle of the load voltage as compared to supply voltage even in buck mode, that is very difficult in other ZS ac-ac converters. Simulation results demonstrate the new features of improved quasi-ZS ac-ac converter.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130580935","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343303
Manohar Singh, K. Meera, Paritosh Joshi, Prem Prakash
Mostly power utilities are connected with national grid at multiple grid interconnection points. Any unattended major disturbance in the national grid, may lead to tripping of inter-/intra-regional transmission lines and loss of generating units. These trippings/loss of generating units further results in load/generation mismatch in the national grid and finally leads to grid failure event. In order to minimize the occurrence of complete grid blackouts in India, regional protection committees are advising the power utilities to install a local defense mechanism to isolate their power network during grid disturbances. Defense mechanism will isolate the local network from the national grid well before grid collapse point to cater essential electric demand in local network with the help of local generation. As per the guideline issued from the regional power committee, an under frequency islanding schemes needs to be designed. The islanding schemes presented in this article works on the principle of load shedding corresponding to different rates of change of frequency and flat under frequency response. The designed protection scheme is implemented and its dynamic performance is assessed in the Delhi Transmission utility. The rate of change of the frequency will be sensed at load dispatch center and predefined load shedding takes place in online mode at 33/66 kV feeder to maintain the load generation balance in the islands(s) within the acceptable stability limits.
{"title":"Islanding scheme for power transmission utilities","authors":"Manohar Singh, K. Meera, Paritosh Joshi, Prem Prakash","doi":"10.1109/CERA.2017.8343303","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343303","url":null,"abstract":"Mostly power utilities are connected with national grid at multiple grid interconnection points. Any unattended major disturbance in the national grid, may lead to tripping of inter-/intra-regional transmission lines and loss of generating units. These trippings/loss of generating units further results in load/generation mismatch in the national grid and finally leads to grid failure event. In order to minimize the occurrence of complete grid blackouts in India, regional protection committees are advising the power utilities to install a local defense mechanism to isolate their power network during grid disturbances. Defense mechanism will isolate the local network from the national grid well before grid collapse point to cater essential electric demand in local network with the help of local generation. As per the guideline issued from the regional power committee, an under frequency islanding schemes needs to be designed. The islanding schemes presented in this article works on the principle of load shedding corresponding to different rates of change of frequency and flat under frequency response. The designed protection scheme is implemented and its dynamic performance is assessed in the Delhi Transmission utility. The rate of change of the frequency will be sensed at load dispatch center and predefined load shedding takes place in online mode at 33/66 kV feeder to maintain the load generation balance in the islands(s) within the acceptable stability limits.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132919572","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343338
Pankaj Dahiya, P. Mukhija, A. Saxena
The objective of this paper is to develop a control strategy for frequency regulation of single area thermal power system. As the available bandwidth in open communication channel is limited and transmitting control signal regularly imposes a burden on the channel. Therefore, to reduce the burden on communication channel, event-triggered control scheme is a natural choice. In this paper, first a state feedback controller is designed. Then based on the event-trigger condition, two event-triggered controllers are also designed. For all these controllers, simulations studies are performed to give the frequency deviation responses. The simulations demonstrate that the number of samples being transmitted is greatly reduced.
{"title":"Event-triggered control for frequency regulation of single-area thermal power system","authors":"Pankaj Dahiya, P. Mukhija, A. Saxena","doi":"10.1109/CERA.2017.8343338","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343338","url":null,"abstract":"The objective of this paper is to develop a control strategy for frequency regulation of single area thermal power system. As the available bandwidth in open communication channel is limited and transmitting control signal regularly imposes a burden on the channel. Therefore, to reduce the burden on communication channel, event-triggered control scheme is a natural choice. In this paper, first a state feedback controller is designed. Then based on the event-trigger condition, two event-triggered controllers are also designed. For all these controllers, simulations studies are performed to give the frequency deviation responses. The simulations demonstrate that the number of samples being transmitted is greatly reduced.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130842028","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343291
Umesh Chaudhary
This paper presents a optimization method for power regulation in a wind turbine which is coupled with doubly-fed induction generator (DFIG) through the gear-box system. In this method, the blade pitch angle and turbine shaft speed are dynamically varied in order to keep the captured power as close to the rated power as possible. The vector based control technique has been successfully implemented on the DFIG system for the required variable speed operation. The genetic algorithm has proposed to get optimal tip speed ratio to extract maximum possible power. The capacity of this method to handle fast varying wind speeds has been verified using MATLAB simulations.
{"title":"Optimization method for power regulation in wind turbine coupled to doubly-fed induction generator","authors":"Umesh Chaudhary","doi":"10.1109/CERA.2017.8343291","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343291","url":null,"abstract":"This paper presents a optimization method for power regulation in a wind turbine which is coupled with doubly-fed induction generator (DFIG) through the gear-box system. In this method, the blade pitch angle and turbine shaft speed are dynamically varied in order to keep the captured power as close to the rated power as possible. The vector based control technique has been successfully implemented on the DFIG system for the required variable speed operation. The genetic algorithm has proposed to get optimal tip speed ratio to extract maximum possible power. The capacity of this method to handle fast varying wind speeds has been verified using MATLAB simulations.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134245169","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343297
J. Mishra, M. Pattnaik, S. Samanta
An efficient speed sensorless stand-alone wind-battery hybrid system is proposed in this work. A simple Maximum power point tracking (MPPT) controller scheme is presented for optimal control of power. Furthermore, a battery controller is used, which maintains dc link voltage. The merit of the system is that it doesn't require an anemometer and an encoder for sensing the wind speeds and rotor speed for MPPT control. In addition, the battery controller is assisting the dc link voltage to maintain the set value for over and under generation periods. The results show that the controller can extract maximum power and regulate the dc link voltage irrespective of wind speed variations.
{"title":"Speed sensorless MPPT control of stand-alone SEIG based wind-battery hybrid system","authors":"J. Mishra, M. Pattnaik, S. Samanta","doi":"10.1109/CERA.2017.8343297","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343297","url":null,"abstract":"An efficient speed sensorless stand-alone wind-battery hybrid system is proposed in this work. A simple Maximum power point tracking (MPPT) controller scheme is presented for optimal control of power. Furthermore, a battery controller is used, which maintains dc link voltage. The merit of the system is that it doesn't require an anemometer and an encoder for sensing the wind speeds and rotor speed for MPPT control. In addition, the battery controller is assisting the dc link voltage to maintain the set value for over and under generation periods. The results show that the controller can extract maximum power and regulate the dc link voltage irrespective of wind speed variations.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129553972","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343372
Hadhiq Khan, M. A. Bazaz, S. A. Nahvi
High-fidelity models of power electronic converters incorporating effects of parasitics, switching non-linearities etc. are too slow to simulate. This paper explores the application of Model Order Reduction (MOR) techniques for simulation acceleration in power electronics.
{"title":"Model order reduction of power electronic circuits","authors":"Hadhiq Khan, M. A. Bazaz, S. A. Nahvi","doi":"10.1109/CERA.2017.8343372","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343372","url":null,"abstract":"High-fidelity models of power electronic converters incorporating effects of parasitics, switching non-linearities etc. are too slow to simulate. This paper explores the application of Model Order Reduction (MOR) techniques for simulation acceleration in power electronics.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116369103","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343388
Peeyush Kala, Sudha Arora
Selective harmonic elimination (SHE) techniques are widely employed in multilevel inverters (MLIs) for the calculation of switching angles in such a manner that the desired fundamental output voltage is obtained while simultaneously eliminating the dominant low order harmonics. In order to obtain this objective, the solution of nonlinear transcendental equations by means of algebraic, iterative and optimization techniques is required. In this article, Gravitational Search Algorithm (GSA) based SHE technique is applied to find the optimum switching angles for 11-level cascaded MLI. A comparative study has been carried out which showed that the GSA based SHE method provided more precise results with less number of iterations as compared to the Genetic Algorithm (GA) based SHE method. GSA based SHE technique has been programmed in MATLAB/Simulink software environment. Simulation and harmonic analysis results exhibit the efficacy of GSA in the elimination of low order harmonics while obtaining the desired fundamental voltage at the same time.
{"title":"Selective harmonic elimination in multilevel inverters using gravitational search algorithm","authors":"Peeyush Kala, Sudha Arora","doi":"10.1109/CERA.2017.8343388","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343388","url":null,"abstract":"Selective harmonic elimination (SHE) techniques are widely employed in multilevel inverters (MLIs) for the calculation of switching angles in such a manner that the desired fundamental output voltage is obtained while simultaneously eliminating the dominant low order harmonics. In order to obtain this objective, the solution of nonlinear transcendental equations by means of algebraic, iterative and optimization techniques is required. In this article, Gravitational Search Algorithm (GSA) based SHE technique is applied to find the optimum switching angles for 11-level cascaded MLI. A comparative study has been carried out which showed that the GSA based SHE method provided more precise results with less number of iterations as compared to the Genetic Algorithm (GA) based SHE method. GSA based SHE technique has been programmed in MATLAB/Simulink software environment. Simulation and harmonic analysis results exhibit the efficacy of GSA in the elimination of low order harmonics while obtaining the desired fundamental voltage at the same time.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131837733","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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