Pub Date : 2014-09-01DOI: 10.1109/ISEG.2014.7005611
N. Rao, J. Amarnath, V. P. Rao
This paper focuses on the enhancement Available Transfer Capability using FACTS devices. ATC is calculated on the location of FACTS devises based on the VAR loss sensitivity index method, Real power loss index method. Comparison is made for performance of FACTS devises based on the optimal location methods. Available Transfer capability is Enhanced by Multi type FACTS devises i.e combination of TCSC and TCSC, TCPAR and TCPAR, TCSCand TCPAR. Results are simulated on modified IEEE-9bus system with a powerworld simulator 8.0.
{"title":"Comparison for performance of multitype FACTS devises on available transfer capability in a deregulated power system","authors":"N. Rao, J. Amarnath, V. P. Rao","doi":"10.1109/ISEG.2014.7005611","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005611","url":null,"abstract":"This paper focuses on the enhancement Available Transfer Capability using FACTS devices. ATC is calculated on the location of FACTS devises based on the VAR loss sensitivity index method, Real power loss index method. Comparison is made for performance of FACTS devises based on the optimal location methods. Available Transfer capability is Enhanced by Multi type FACTS devises i.e combination of TCSC and TCSC, TCPAR and TCPAR, TCSCand TCPAR. Results are simulated on modified IEEE-9bus system with a powerworld simulator 8.0.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126311858","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 : 2014-09-01DOI: 10.1109/ISEG.2014.7005593
Suresh Billakanti, C. Venkaiah
The Phasor Measuring Units provide synchronized measurements for monitoring and control of Power System State for Power System protection. The high PMU cost and installation cost are main reasons for minimizing the number of PMUs and their optimal placement should ensure Power System full Observability. This paper presents the investigation of Optimal placement of Phasor Measuring Units (PMU) and the use of reduced number of PMUs for ensuring Power system full observability. The Optimal PMU Placement (OPP) problem has been tackled considering different cases like with and without conventional measurements and zero injection buses. The OPP is considered for different contingencies such as single PMU or line outage to ensure full system observability. The PMU Channels, which limit the number of measurements at the installed bus is also taken into account in OPP formulation. MATLAB Simulations are carried out by Binary Integer Linear programming (BILP) method and tested on standard IEEE 14-bus, IEEE 30-bus, IEEE 57-bus and IEEE 118-bus systems. The results presented were compared with the recent literature and found the effectiveness of proposed method with regard to number of PMUs and execution time is appreciable.
{"title":"An effective binary integer linear programmed approach for optimal placement of PMUs in power systems","authors":"Suresh Billakanti, C. Venkaiah","doi":"10.1109/ISEG.2014.7005593","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005593","url":null,"abstract":"The Phasor Measuring Units provide synchronized measurements for monitoring and control of Power System State for Power System protection. The high PMU cost and installation cost are main reasons for minimizing the number of PMUs and their optimal placement should ensure Power System full Observability. This paper presents the investigation of Optimal placement of Phasor Measuring Units (PMU) and the use of reduced number of PMUs for ensuring Power system full observability. The Optimal PMU Placement (OPP) problem has been tackled considering different cases like with and without conventional measurements and zero injection buses. The OPP is considered for different contingencies such as single PMU or line outage to ensure full system observability. The PMU Channels, which limit the number of measurements at the installed bus is also taken into account in OPP formulation. MATLAB Simulations are carried out by Binary Integer Linear programming (BILP) method and tested on standard IEEE 14-bus, IEEE 30-bus, IEEE 57-bus and IEEE 118-bus systems. The results presented were compared with the recent literature and found the effectiveness of proposed method with regard to number of PMUs and execution time is appreciable.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128064644","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 : 2014-09-01DOI: 10.1109/ISEG.2014.7005597
K. S. Kumar, B. Basavaraja, B. V. Sanker Ram
The main objective of this paper is that the optimization is to perform a best utilization of existing transmission lines. And also an attempt has been made to optimize each objective individually using Particle Swarm Optimization. The so developed algorithm for Optimization of each objective is to be tested on power systems i.e. on IEEE 14 bus system. In this connection, the FACTS devices like STATCOM and IPFC are optimally placed in order to optimize the power losses while considering voltage constraints. This also improves the power transfer capability and voltage profile of the system. Simulations are performed on an IEEE 14-bus system and results are presented.
{"title":"Optimal placement of facts devices with available transfer capability enhancement","authors":"K. S. Kumar, B. Basavaraja, B. V. Sanker Ram","doi":"10.1109/ISEG.2014.7005597","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005597","url":null,"abstract":"The main objective of this paper is that the optimization is to perform a best utilization of existing transmission lines. And also an attempt has been made to optimize each objective individually using Particle Swarm Optimization. The so developed algorithm for Optimization of each objective is to be tested on power systems i.e. on IEEE 14 bus system. In this connection, the FACTS devices like STATCOM and IPFC are optimally placed in order to optimize the power losses while considering voltage constraints. This also improves the power transfer capability and voltage profile of the system. Simulations are performed on an IEEE 14-bus system and results are presented.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127675431","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 : 2014-09-01DOI: 10.1109/ISEG.2014.7005592
Prashant Kumar, S. Reddy
Paper narrates the optimization of residual flux in network transformers by using MATLAB Simulation. The purpose of the paper is to mitigation a large inrush currents taken by various transformers when a feeder is energized. Here Time-domain simulations are used to prove that a small-power device can substantially reduce the residual flux of all transformers simultaneously. The device used in this paper consists of a low-voltage dc source. Before a feeder is re-energized, the residual flux is reduced to a minimum level and as a consequence, the large inrush currents are reduced to an acceptable level. This greatly improves the probability for the feeder to be successfully energized when otherwise a false trip would have occurred. Inrush current reductions of more than 60% are obtained at the head of the feeder.
{"title":"Optimization of inrush current in electrical transformer","authors":"Prashant Kumar, S. Reddy","doi":"10.1109/ISEG.2014.7005592","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005592","url":null,"abstract":"Paper narrates the optimization of residual flux in network transformers by using MATLAB Simulation. The purpose of the paper is to mitigation a large inrush currents taken by various transformers when a feeder is energized. Here Time-domain simulations are used to prove that a small-power device can substantially reduce the residual flux of all transformers simultaneously. The device used in this paper consists of a low-voltage dc source. Before a feeder is re-energized, the residual flux is reduced to a minimum level and as a consequence, the large inrush currents are reduced to an acceptable level. This greatly improves the probability for the feeder to be successfully energized when otherwise a false trip would have occurred. Inrush current reductions of more than 60% are obtained at the head of the feeder.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120991008","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 : 2014-09-01DOI: 10.1109/ISEG.2014.7005387
K. Srinivas, S. Tulasi Ram
In this paper the proposed control algorithm for three phase four wire shunt active power filter (APF) compensate the unbalanced and non-linear loads. The control algorithm is implemented in MAT LAB environment to improve the one of main power quality problem under steady state transient conditions in distribution system considering different loading conditions. In this algorithm the theory of instantaneous symmetrical component used to extract a positive sequence of the supply voltage to generated reference compensator currents under unbalanced non stiff source voltage. The filter has to develop reference filter currents according to that the filter has to inject active or reactive power into the system by operating VSI in current controlled mode. The active power filter is implemented with pulse width modulation based current controlled voltage source inverter. The switching signals for VSI are generated through proposed three level hysteresis current controllers. The simulation results showing that the shunt active power filter is effectively compensating the supply current and reactive power at the point of common coupling.
{"title":"A fast dynamic response of three phase four wire shunt active power filter under unbalanced non stiff source","authors":"K. Srinivas, S. Tulasi Ram","doi":"10.1109/ISEG.2014.7005387","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005387","url":null,"abstract":"In this paper the proposed control algorithm for three phase four wire shunt active power filter (APF) compensate the unbalanced and non-linear loads. The control algorithm is implemented in MAT LAB environment to improve the one of main power quality problem under steady state transient conditions in distribution system considering different loading conditions. In this algorithm the theory of instantaneous symmetrical component used to extract a positive sequence of the supply voltage to generated reference compensator currents under unbalanced non stiff source voltage. The filter has to develop reference filter currents according to that the filter has to inject active or reactive power into the system by operating VSI in current controlled mode. The active power filter is implemented with pulse width modulation based current controlled voltage source inverter. The switching signals for VSI are generated through proposed three level hysteresis current controllers. The simulation results showing that the shunt active power filter is effectively compensating the supply current and reactive power at the point of common coupling.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127072289","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 : 2014-09-01DOI: 10.1109/ISEG.2014.7005607
K. Sarada, V. Bapiraju
Price prognostication has become progressively relevant to producers and shoppers within the new competitive wattage markets. Both for spot markets and long term contractors, value forecasts square measure necessary to develop bidding ways. In this paper, Genetic Algorithm based Neural network (GANN) approach is used to forecast short term hourly electricity price and the results are compared with Aritificial Neural Network(ANN). The recommended method is studied on the PJM electricity market. The results achieved through the simulation illustrates that the proposed model offers exact and improved results.
{"title":"Comparison of day-ahead price forecasting in energy market using Neural Network and Genetic Algorithm","authors":"K. Sarada, V. Bapiraju","doi":"10.1109/ISEG.2014.7005607","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005607","url":null,"abstract":"Price prognostication has become progressively relevant to producers and shoppers within the new competitive wattage markets. Both for spot markets and long term contractors, value forecasts square measure necessary to develop bidding ways. In this paper, Genetic Algorithm based Neural network (GANN) approach is used to forecast short term hourly electricity price and the results are compared with Aritificial Neural Network(ANN). The recommended method is studied on the PJM electricity market. The results achieved through the simulation illustrates that the proposed model offers exact and improved results.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131556409","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 : 2014-09-01DOI: 10.1109/ISEG.2014.7005616
R. Mishra, P. M. Deoghare, Chetan Bhale, S. Lanjewar
Now a days the demand of electrical energy continuously increasing day by day, to fulfill this demand the electrical power network becomes complicated. Wavelet analysis which is a mathematical tool for signal analysis is used to detect and classify the type of fault occurring on the transmission line. This paper presents an improved algorithm for transmission line fault classification by using wavelet. Use of Impedance measurement technique and travelling wave theory is adopted here for the location of fault. Discrete wavelet transform of current signals is utilized for fault classification. MATLAB/Simulation is used to generate fault signals. Simulation results reveal that the performance of the proposed fault detection indicator is promising and easy to implement for computer relaying application.
{"title":"Wavelet based transmission line fault classification and location","authors":"R. Mishra, P. M. Deoghare, Chetan Bhale, S. Lanjewar","doi":"10.1109/ISEG.2014.7005616","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005616","url":null,"abstract":"Now a days the demand of electrical energy continuously increasing day by day, to fulfill this demand the electrical power network becomes complicated. Wavelet analysis which is a mathematical tool for signal analysis is used to detect and classify the type of fault occurring on the transmission line. This paper presents an improved algorithm for transmission line fault classification by using wavelet. Use of Impedance measurement technique and travelling wave theory is adopted here for the location of fault. Discrete wavelet transform of current signals is utilized for fault classification. MATLAB/Simulation is used to generate fault signals. Simulation results reveal that the performance of the proposed fault detection indicator is promising and easy to implement for computer relaying application.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115935179","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 : 2014-09-01DOI: 10.1109/ISEG.2014.7005390
N. Chaitanya, K. Anjaneyulu, K. Sekhar
A utility interface converter is one of the key components in the hybrid power systems. This Paper addresses a novel three phase interleaved bi directional power converter circuit for economical solar, wind & battery hybrid power system (HPS). HPS consists of both AC and DC networks connected together by three phase interleaved bi directional converter in combination with 3phase pulse width modulation controlled converter. Here PWM controlled converter switches are used for smooth power transfer between AC and DC links and to maintain stable operation with various renewable sources (Both AC and DC), different loads. The addressed hybrid architecture is very flexible to decrease the required power conversions stages and hence the system cost and efficiency. The HPS is simulated in MATLAB/Simulink Environment and the simulation results show that the system can maintain stable operation with three phase interleaved bi directional converter both in the grid tied, autonomous modes.
{"title":"Performance analysis of a hybrid power system with three phase interleaved bidirectional converter","authors":"N. Chaitanya, K. Anjaneyulu, K. Sekhar","doi":"10.1109/ISEG.2014.7005390","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005390","url":null,"abstract":"A utility interface converter is one of the key components in the hybrid power systems. This Paper addresses a novel three phase interleaved bi directional power converter circuit for economical solar, wind & battery hybrid power system (HPS). HPS consists of both AC and DC networks connected together by three phase interleaved bi directional converter in combination with 3phase pulse width modulation controlled converter. Here PWM controlled converter switches are used for smooth power transfer between AC and DC links and to maintain stable operation with various renewable sources (Both AC and DC), different loads. The addressed hybrid architecture is very flexible to decrease the required power conversions stages and hence the system cost and efficiency. The HPS is simulated in MATLAB/Simulink Environment and the simulation results show that the system can maintain stable operation with three phase interleaved bi directional converter both in the grid tied, autonomous modes.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116678722","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 : 2014-09-01DOI: 10.1109/ISEG.2014.7005613
G. Naresh, M. Raju, S. Narasimham
Power System Stabilizers (PSS) are incorporated in the excitation system to enhance the damping of low frequency oscillations. In this paper, the design of multiple PSS in a multimachine power system (MMPS) using clonal selection algorithm (CSA) has been proposed. The design problem of the PSS has been formulated as an optimization problem and CSA has been employed to search for optimal controller parameters. It has been shown that the stability performance of the system can be improved by minimizing the eigenvalue based objective function comprising of the damping factor and the damping ratio of the poorly damped electromechanical modes. Eigenvalue analysis and nonlinear simulation results have also been presented for various loading conditions and system configurations to show the effectiveness and robustness of the proposed controllers and their ability to provide efficient damping of low frequency oscillations.
{"title":"Design of clonal selection algorithm based PSS for damping power system oscillations","authors":"G. Naresh, M. Raju, S. Narasimham","doi":"10.1109/ISEG.2014.7005613","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005613","url":null,"abstract":"Power System Stabilizers (PSS) are incorporated in the excitation system to enhance the damping of low frequency oscillations. In this paper, the design of multiple PSS in a multimachine power system (MMPS) using clonal selection algorithm (CSA) has been proposed. The design problem of the PSS has been formulated as an optimization problem and CSA has been employed to search for optimal controller parameters. It has been shown that the stability performance of the system can be improved by minimizing the eigenvalue based objective function comprising of the damping factor and the damping ratio of the poorly damped electromechanical modes. Eigenvalue analysis and nonlinear simulation results have also been presented for various loading conditions and system configurations to show the effectiveness and robustness of the proposed controllers and their ability to provide efficient damping of low frequency oscillations.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115352631","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 : 2014-09-01DOI: 10.1109/ISEG.2014.7005594
Phanindra Kumar Ganivada, C. Venkaiah
In this paper a new optimization algorithm TLBO (Teaching and Learning Based Optimization) has been implemented to solve optimal multi Distributed Generator (DG) placement problem. This problem has been formulated for minimization of loss, capacity release of transmission lines and voltage profile improvement. To reduce search space and computational burden optimization has been done in two stages first to find the optimal locations for DG placement and latter to find the optimal size of each DG. The proposed TLBO technique has been tested on IEEE 33 bus and IEEE 69 bus radial distribution system. The results have been compared with well known algorithms in literature like GA (Genetic Algorithm) and PSO (Particle Swarm Optimization). A study on effect of DG size and power factor on system performance is done. Results showed significant reduction in power loss and line flows and significant improvement in voltage profile.
本文提出了一种基于教与学的优化算法TLBO (Teaching and Learning Based optimization)来解决分布式发电机组的最优配置问题。这个问题是为了尽量减少损耗，释放输电线路的容量和改善电压分布而制定的。为了减少搜索空间和计算量，优化分为两个阶段，首先是寻找DG的最优放置位置，然后是寻找每个DG的最优大小。所提出的TLBO技术已在IEEE 33总线和IEEE 69总线径向配电系统上进行了测试。结果与文献中已知的遗传算法(GA)和粒子群算法(PSO)进行了比较。研究了DG尺寸和功率因数对系统性能的影响。结果显示，功率损耗和线路流量显著减少，电压分布显著改善。
{"title":"Optimal placement and sizing of multi distributed generators using teaching and learning based optimization","authors":"Phanindra Kumar Ganivada, C. Venkaiah","doi":"10.1109/ISEG.2014.7005594","DOIUrl":"https://doi.org/10.1109/ISEG.2014.7005594","url":null,"abstract":"In this paper a new optimization algorithm TLBO (Teaching and Learning Based Optimization) has been implemented to solve optimal multi Distributed Generator (DG) placement problem. This problem has been formulated for minimization of loss, capacity release of transmission lines and voltage profile improvement. To reduce search space and computational burden optimization has been done in two stages first to find the optimal locations for DG placement and latter to find the optimal size of each DG. The proposed TLBO technique has been tested on IEEE 33 bus and IEEE 69 bus radial distribution system. The results have been compared with well known algorithms in literature like GA (Genetic Algorithm) and PSO (Particle Swarm Optimization). A study on effect of DG size and power factor on system performance is done. Results showed significant reduction in power loss and line flows and significant improvement in voltage profile.","PeriodicalId":105826,"journal":{"name":"2014 International Conference on Smart Electric Grid (ISEG)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127568572","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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