Pub Date : 2012-06-06DOI: 10.1109/PEOCO.2012.6230838
M. M. Aman, G. Jasmon, Q. Khan, A. Bakar, M. N. Abdullah
Modeling tools are useful for educational and industrial use. Such tools help the new engineers to simulate the power system under normal and faulty conditions. This paper presents the design and various data conversion steps of a digital negative sequence relay. The digital relay has a superiority over electromechanical relay in terms of accuracy and speed. The detection of negative sequence current and appropriate action is useful for protection of power system components. The operation of relay should be fast and reliable for minimum outage of power system in case of abnormality or electrical fault. In this paper, the relay performance under different system dynamics is also visualized on MATLAB / SIMULINK® considering a 400V power system.
{"title":"Modeling and simulation of digital negative sequence relay for unbalanced protection of generator","authors":"M. M. Aman, G. Jasmon, Q. Khan, A. Bakar, M. N. Abdullah","doi":"10.1109/PEOCO.2012.6230838","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230838","url":null,"abstract":"Modeling tools are useful for educational and industrial use. Such tools help the new engineers to simulate the power system under normal and faulty conditions. This paper presents the design and various data conversion steps of a digital negative sequence relay. The digital relay has a superiority over electromechanical relay in terms of accuracy and speed. The detection of negative sequence current and appropriate action is useful for protection of power system components. The operation of relay should be fast and reliable for minimum outage of power system in case of abnormality or electrical fault. In this paper, the relay performance under different system dynamics is also visualized on MATLAB / SIMULINK® considering a 400V power system.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124951710","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 : 2012-06-06DOI: 10.1109/PEOCO.2012.6230849
Kuan-Hung Liu, Dung-Rung Hsieh, Jen-Yuan Hsu, S. Chang
In a multi-user power line communication (PLC) home network, there are several methods to decide who has the right to use the channel to send data. Basically, there are two kinds of scheduling schemes: coordinated and contention-based. For coordinated scheduling scheme, the manager of PLC network, called domain master, will arrange available medium for users according to network resources and users' requirements. The other scheduling scheme, called contention-based, is that users contend for the medium in a transmission opportunity (TXOP) and the user who wins the contention can transmit a data frame or a data frame sequence. In this paper, we propose an adaptive MAC protocol by adjusting data rate and contention window size based on users' defer situations and channel conditions to improve the system throughput. We provide a theorem to show the limit of throughput achievable by the proposed system and perform extensive simulation to verify that the proposed MAC protocol can indeed improve the system throughput by 45% in PLC home networks.
{"title":"Throughput improvement for power line communication by adaptive MAC protocol","authors":"Kuan-Hung Liu, Dung-Rung Hsieh, Jen-Yuan Hsu, S. Chang","doi":"10.1109/PEOCO.2012.6230849","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230849","url":null,"abstract":"In a multi-user power line communication (PLC) home network, there are several methods to decide who has the right to use the channel to send data. Basically, there are two kinds of scheduling schemes: coordinated and contention-based. For coordinated scheduling scheme, the manager of PLC network, called domain master, will arrange available medium for users according to network resources and users' requirements. The other scheduling scheme, called contention-based, is that users contend for the medium in a transmission opportunity (TXOP) and the user who wins the contention can transmit a data frame or a data frame sequence. In this paper, we propose an adaptive MAC protocol by adjusting data rate and contention window size based on users' defer situations and channel conditions to improve the system throughput. We provide a theorem to show the limit of throughput achievable by the proposed system and perform extensive simulation to verify that the proposed MAC protocol can indeed improve the system throughput by 45% in PLC home networks.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115562864","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 : 2012-06-06DOI: 10.1109/PEOCO.2012.6230836
A. Shahriari, H. Mokhlis, A. Bakar, M. Karimi, J. Laghari, M. Kazeminezad
This paper implements the State Space Search Method (SSSM) in polar coordinate form to calculate low voltage solution and Maximum Loading Point of system in ill conditioned system. SSSM modifies the direction of state variable (buses voltage and phase) by using optimal multiplier in order to converge load flow equations in ill conditioned system. The privilege of SSSM emerges in the keeping dimension of load flow jacobian matrix constant. While another method such as continuation and homotopy methods change the framework of jacobian matrix based on predictor and corrector in term of increasing load demand. Indeed, the calculation process of SSSM is based on standard Newton Raphson load flow method. The validation of SSSM is shown by the testing IEEE test systems of 14 and 30 in well and maximum loading point as ill-conditioned systems.
{"title":"The calculation of low voltage solution based on state space search method in ill-conditioned system","authors":"A. Shahriari, H. Mokhlis, A. Bakar, M. Karimi, J. Laghari, M. Kazeminezad","doi":"10.1109/PEOCO.2012.6230836","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230836","url":null,"abstract":"This paper implements the State Space Search Method (SSSM) in polar coordinate form to calculate low voltage solution and Maximum Loading Point of system in ill conditioned system. SSSM modifies the direction of state variable (buses voltage and phase) by using optimal multiplier in order to converge load flow equations in ill conditioned system. The privilege of SSSM emerges in the keeping dimension of load flow jacobian matrix constant. While another method such as continuation and homotopy methods change the framework of jacobian matrix based on predictor and corrector in term of increasing load demand. Indeed, the calculation process of SSSM is based on standard Newton Raphson load flow method. The validation of SSSM is shown by the testing IEEE test systems of 14 and 30 in well and maximum loading point as ill-conditioned systems.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117045735","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 : 2012-06-06DOI: 10.1109/PEOCO.2012.6230900
M. Mohammadi, M. Gitizadeh, A. Roosta
Since the penetration of wind power in power system is increasing greatly it is urgent to study the impact of wind power on the dynamic stability of power system. Doubly fed induction generator (DFIG) is widely utilized in large wind power plants. Therefore the dynamic behaviors of DFIG wind turbines is necessary to be studied. This paper presents the impact of static VAr compensator (SVC) on the dynamic stability of power system connected to DFIG. In order to improve the dynamic stability, control parameters of SVC need to be set optimally. In this article, we offer a suitable choice of objective function and then be optimized by genetic algorithm. The dynamic simulation results give us information such as the impact of SVC on the performance of DFIG and synchronous generators dynamic performance. MATLAB is used for executing the dynamic simulation.
{"title":"Dynamic stability improvement of a power system incorporating DFIG wind power plant using optimized control parameters of a SVC","authors":"M. Mohammadi, M. Gitizadeh, A. Roosta","doi":"10.1109/PEOCO.2012.6230900","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230900","url":null,"abstract":"Since the penetration of wind power in power system is increasing greatly it is urgent to study the impact of wind power on the dynamic stability of power system. Doubly fed induction generator (DFIG) is widely utilized in large wind power plants. Therefore the dynamic behaviors of DFIG wind turbines is necessary to be studied. This paper presents the impact of static VAr compensator (SVC) on the dynamic stability of power system connected to DFIG. In order to improve the dynamic stability, control parameters of SVC need to be set optimally. In this article, we offer a suitable choice of objective function and then be optimized by genetic algorithm. The dynamic simulation results give us information such as the impact of SVC on the performance of DFIG and synchronous generators dynamic performance. MATLAB is used for executing the dynamic simulation.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117332939","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 : 2012-06-06DOI: 10.1109/PEOCO.2012.6230890
B. Aranjo, P. K. Soori, P. Talukder
Robotics is one area where the use of stepper motors is of paramount importance. Robotic applications require precise movements. This paper presents an efficient and versatile drive system for stepper motors for use in robotic applications. The proposed drive system delivers precise control with the smallest possible step angle. A model of the permanent magnet stepper motor is simulated using MATLAB Simulink simulation software. The software and the hardware circuits of the stepper motor drive is designed and tested for different types of movements of the stepper motor. The proposed circuitry consists of the design of power supply circuit, microcontroller, buffer and a driver circuit. Unlike a manual controller, the AT89C51 microcontroller is programmed to have user friendliness so that the user can select the required movement of the stepper motor. The drive system allows the movement of the stepper motor to be controlled by selecting options of half or full step, forward or reverse movement and the speed in RPM or the fixed number of steps that it should move.
{"title":"Stepper motor drives for robotic applications","authors":"B. Aranjo, P. K. Soori, P. Talukder","doi":"10.1109/PEOCO.2012.6230890","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230890","url":null,"abstract":"Robotics is one area where the use of stepper motors is of paramount importance. Robotic applications require precise movements. This paper presents an efficient and versatile drive system for stepper motors for use in robotic applications. The proposed drive system delivers precise control with the smallest possible step angle. A model of the permanent magnet stepper motor is simulated using MATLAB Simulink simulation software. The software and the hardware circuits of the stepper motor drive is designed and tested for different types of movements of the stepper motor. The proposed circuitry consists of the design of power supply circuit, microcontroller, buffer and a driver circuit. Unlike a manual controller, the AT89C51 microcontroller is programmed to have user friendliness so that the user can select the required movement of the stepper motor. The drive system allows the movement of the stepper motor to be controlled by selecting options of half or full step, forward or reverse movement and the speed in RPM or the fixed number of steps that it should move.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123868336","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 : 2012-06-06DOI: 10.1109/PEOCO.2012.6230879
M. S. I. Khan, H. Maruf, M. Ahmed, M. A. Choudhury
We have proposed and simulated recessed Y-gate AlN/GaN/AlGaN DHFET structure with GaN cap layer at drain side of the gate as well as compared its simulated characteristics with the conventional DHFET. The threshold voltage of the proposed device was increased 0.2V to the positive side. Use of GaN cap at the gate side-wall effectively reduced electric field concentration at the gate edge of the proposed device compared to the conventional one, which also ensured the leakage current of the proposed device was 1 order less than that of conventional device. The forward characteristics of proposed device are slightly degraded due to the recessed gate structure which entered the channel region and 1-nm thin layer of AlN layer.
{"title":"Recessed Y-gate AlN/GaN/AlGaN DHFET with GaN cap layer at the gate edge","authors":"M. S. I. Khan, H. Maruf, M. Ahmed, M. A. Choudhury","doi":"10.1109/PEOCO.2012.6230879","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230879","url":null,"abstract":"We have proposed and simulated recessed Y-gate AlN/GaN/AlGaN DHFET structure with GaN cap layer at drain side of the gate as well as compared its simulated characteristics with the conventional DHFET. The threshold voltage of the proposed device was increased 0.2V to the positive side. Use of GaN cap at the gate side-wall effectively reduced electric field concentration at the gate edge of the proposed device compared to the conventional one, which also ensured the leakage current of the proposed device was 1 order less than that of conventional device. The forward characteristics of proposed device are slightly degraded due to the recessed gate structure which entered the channel region and 1-nm thin layer of AlN layer.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"19 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120910137","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 : 2012-06-06DOI: 10.1109/PEOCO.2012.6230874
A. Bhardwaj, Vikram Kumar Kamboj, V. Shukla, B. Singh, P. Khurana
This paper brings out the studies of generation scheduling problem in an electrical power system. This paper presents some general reviews of research and developments in the field of unit commitment based on published articles and web-sites. Here, it is set about to perform a comprehensive survey of research work made in the domain of Unit Commitment using various techniques. This may be a helpful tool for the researchers, scientists or investigators working in the area of unit commitment.
{"title":"Unit commitment in electrical power system-a literature review","authors":"A. Bhardwaj, Vikram Kumar Kamboj, V. Shukla, B. Singh, P. Khurana","doi":"10.1109/PEOCO.2012.6230874","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230874","url":null,"abstract":"This paper brings out the studies of generation scheduling problem in an electrical power system. This paper presents some general reviews of research and developments in the field of unit commitment based on published articles and web-sites. Here, it is set about to perform a comprehensive survey of research work made in the domain of Unit Commitment using various techniques. This may be a helpful tool for the researchers, scientists or investigators working in the area of unit commitment.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114068692","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 : 2012-06-06DOI: 10.1109/PEOCO.2012.6230897
Omar H. Abdalla, R. Albadwawi, H. Al-Hadi, H. Al-Riyami, A. Al-Nadabi
The paper presents steady-state and transient studies to assess the impact of a 200 MW Central Receiver Solar Power Plant (CRSPP) connection on the Main Interconnected Transmission System (MITS) of Oman. The CRSPP consists mainly of a central solar receiver, power tower, thousands of heliostats, molten salt storage tanks, heat exchangers, steam generator, steam turbine, synchronous generator, and step-up transformer. Two proposed locations are considered to connect the CRSPP plant to MITS: Manah 132 kV and Adam 132/33 kV grid stations. The 2015 transmission grid model has been updated to include the simulation of the proposed 200 MW CRSPP using the DIgSILENT PowerFactory professional software. The studies include load flow analysis and short-circuit level calculations in addition to transient responses to three-phase fault and complete CRSPP outage. The results have shown that the connection of the proposed CRSPP plant to the MITS is acceptable.
{"title":"Impact of a 200 MW concentrated receiver solar power plant on steady-state and transient performances of Oman transmission system","authors":"Omar H. Abdalla, R. Albadwawi, H. Al-Hadi, H. Al-Riyami, A. Al-Nadabi","doi":"10.1109/PEOCO.2012.6230897","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230897","url":null,"abstract":"The paper presents steady-state and transient studies to assess the impact of a 200 MW Central Receiver Solar Power Plant (CRSPP) connection on the Main Interconnected Transmission System (MITS) of Oman. The CRSPP consists mainly of a central solar receiver, power tower, thousands of heliostats, molten salt storage tanks, heat exchangers, steam generator, steam turbine, synchronous generator, and step-up transformer. Two proposed locations are considered to connect the CRSPP plant to MITS: Manah 132 kV and Adam 132/33 kV grid stations. The 2015 transmission grid model has been updated to include the simulation of the proposed 200 MW CRSPP using the DIgSILENT PowerFactory professional software. The studies include load flow analysis and short-circuit level calculations in addition to transient responses to three-phase fault and complete CRSPP outage. The results have shown that the connection of the proposed CRSPP plant to the MITS is acceptable.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"22 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113977182","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 : 2012-06-06DOI: 10.1109/PEOCO.2012.6230924
N. A. Arzeha, M. Mustafa, R. Idris
Static VAR Compensator (SVC) has been used as a supplementary controller to improve transient stability and power oscillation damping of the system. A fuzzy logic controller combined with PI controller for SVC is discussed in this paper. The discussed controller is been tested on a test system consists of a 2-machines 3-bus system. The performance of the fuzzy-based SVC controller to damp oscillation of several parameters after being subjected to disturbance is observed. The parameters observed include difference of rotor angle, speed of machines, terminal voltage of buses and transmission line active power. The results show that the fuzzy-based SVC controller gives better performance as compared to system implemented with the conventional SVC.
{"title":"Fuzzy-based Static VAR Compensator controller for damping power system disturbances","authors":"N. A. Arzeha, M. Mustafa, R. Idris","doi":"10.1109/PEOCO.2012.6230924","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230924","url":null,"abstract":"Static VAR Compensator (SVC) has been used as a supplementary controller to improve transient stability and power oscillation damping of the system. A fuzzy logic controller combined with PI controller for SVC is discussed in this paper. The discussed controller is been tested on a test system consists of a 2-machines 3-bus system. The performance of the fuzzy-based SVC controller to damp oscillation of several parameters after being subjected to disturbance is observed. The parameters observed include difference of rotor angle, speed of machines, terminal voltage of buses and transmission line active power. The results show that the fuzzy-based SVC controller gives better performance as compared to system implemented with the conventional SVC.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126283440","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 : 2012-06-06DOI: 10.1109/PEOCO.2012.6230891
M. Shamshiri, C. K. Gan, Chee Wei Tan
In recent decades, smart grid have become increasingly attractive to both energy producers and consumers. Amongst the main challenges for the successful realization of smart grid includes the integration of renewable energy resources, real time demand response and management of intermittent energy resources. Apart from smart grid, the development of micro-grids should take into consideration of issues such as the system performance, modeling, monitoring and controlling of the micro-grids. In particular, the recent advancements in information and communication technologies (ICTs) could facilitate the effective development of the future micro-grid system. This paper presents an overview of smart grids features and highlights the recent development of micro-grid laboratories in Europe, US and Japan.
{"title":"A review of recent development in smart grid and micro-grid laboratories","authors":"M. Shamshiri, C. K. Gan, Chee Wei Tan","doi":"10.1109/PEOCO.2012.6230891","DOIUrl":"https://doi.org/10.1109/PEOCO.2012.6230891","url":null,"abstract":"In recent decades, smart grid have become increasingly attractive to both energy producers and consumers. Amongst the main challenges for the successful realization of smart grid includes the integration of renewable energy resources, real time demand response and management of intermittent energy resources. Apart from smart grid, the development of micro-grids should take into consideration of issues such as the system performance, modeling, monitoring and controlling of the micro-grids. In particular, the recent advancements in information and communication technologies (ICTs) could facilitate the effective development of the future micro-grid system. This paper presents an overview of smart grids features and highlights the recent development of micro-grid laboratories in Europe, US and Japan.","PeriodicalId":138236,"journal":{"name":"2012 IEEE International Power Engineering and Optimization Conference Melaka, Malaysia","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125910514","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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