Pub Date : 1995-11-21DOI: 10.1109/EMPD.1995.500743
W. Lachs, D. Sutanto
The hour by hour changes of demand cannot be accurately forecast because consumers are free to switch appliances at any instant. The greatest uncertainty is posed by the peak periods even though they are of short duration and only use a small proportion of daily energy consumption. Sufficient quantities of energy storage could curtail daily peak demand changes so permitting replacement of demand forecasting by more predictable daily energy forecasts. Not only would it eliminate peaking generation and simplify generator scheduling, but it would also produce a single daily tariff and allow easier financial planning for power system development. The electricity supply industry would incur capital and operating expenditures for the entire power network and additional generators of $6000 to $7000 for each kW of peak demand growth. This expense could be avoided by battery energy storage systems which could curtail peak demand at a cost of $2000 per kW so gaining savings of $4 to $5 billion for a period with 1000 MW growth of peak demand.
{"title":"Uncertainty in electricity supply controlled by energy storage","authors":"W. Lachs, D. Sutanto","doi":"10.1109/EMPD.1995.500743","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500743","url":null,"abstract":"The hour by hour changes of demand cannot be accurately forecast because consumers are free to switch appliances at any instant. The greatest uncertainty is posed by the peak periods even though they are of short duration and only use a small proportion of daily energy consumption. Sufficient quantities of energy storage could curtail daily peak demand changes so permitting replacement of demand forecasting by more predictable daily energy forecasts. Not only would it eliminate peaking generation and simplify generator scheduling, but it would also produce a single daily tariff and allow easier financial planning for power system development. The electricity supply industry would incur capital and operating expenditures for the entire power network and additional generators of $6000 to $7000 for each kW of peak demand growth. This expense could be avoided by battery energy storage systems which could curtail peak demand at a cost of $2000 per kW so gaining savings of $4 to $5 billion for a period with 1000 MW growth of peak demand.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123829799","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500733
H. Le Kim, N. Hadjsaid, J. Sabonnadiere
This paper presents a new approach for contingency selection in power system cyclic security analysis. A fast selection algorithm based on information available in the contingency analysis results from previous cycles and on the local network solution concept applied to two levels of contingency selection is developed. In order to reduce both the number of calculations required for security analysis and the time spent for Jacobian refactorization, a fast pre-screening process without load flow solution is designed initially. The PRESAF module (PRE-Selection Assistee par Filtre) proposed in this phase allows large sets of candidate contingencies to be processed very quickly. Then, a fast screening phase with the SAF module (Selection Assistee par Filtre) processes a small list of selected potentially severe contingencies. Tests on a 206 bus-299 branch 400 kV French model show that the proposed approach is fast and reliable for power system cyclic security analysis.
提出了一种电力系统循环安全分析中应急选择的新方法。提出了一种基于前几个周期的权变分析结果中的可用信息和适用于两级权变选择的局部网络解决方案的快速选择算法。为了减少安全分析所需的计算量和雅可比矩阵重构所花费的时间，初步设计了一种无需负载流解的快速预筛选过程。在此阶段提出的PRESAF模块(预选辅助过滤)允许非常快速地处理大量候选突发事件。然后，使用SAF模块(Selection assstee par filter)的快速筛选阶段处理选定的潜在严重突发事件的小列表。对206母线-299支路400 kV法国模型的试验表明，该方法对电力系统循环安全分析快速可靠。
{"title":"A new contingency selection approach to cyclic security analysis","authors":"H. Le Kim, N. Hadjsaid, J. Sabonnadiere","doi":"10.1109/EMPD.1995.500733","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500733","url":null,"abstract":"This paper presents a new approach for contingency selection in power system cyclic security analysis. A fast selection algorithm based on information available in the contingency analysis results from previous cycles and on the local network solution concept applied to two levels of contingency selection is developed. In order to reduce both the number of calculations required for security analysis and the time spent for Jacobian refactorization, a fast pre-screening process without load flow solution is designed initially. The PRESAF module (PRE-Selection Assistee par Filtre) proposed in this phase allows large sets of candidate contingencies to be processed very quickly. Then, a fast screening phase with the SAF module (Selection Assistee par Filtre) processes a small list of selected potentially severe contingencies. Tests on a 206 bus-299 branch 400 kV French model show that the proposed approach is fast and reliable for power system cyclic security analysis.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130234386","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500727
R. Maruthi, K. Karunakara, M. K. Kumari, K. Srinivasa, Channakeshava
EHV and UHV AC transmission lines and electrical equipment produce electric and magnetic fields around their vicinity. AC conductors used for 220 kV and below are usually designed on the basis of current carrying capacity, whereas those for 400 kV and above have to take into account the electromagnetic fields produced by them. The design of EHV and UHV lines should also consider the consequences of the fields on objects and human beings when their levels are beyond certain limits. Because of this, it is necessary to be able to estimate these electromagnetic fields through computations. A program has been developed for computing the electric and magnetic fields around the transmission lines in India. The computed and the measured values of these fields are presented in this paper for the existing lines in Indian systems.
{"title":"Computation and measurement of AC electric and magnetic field lateral profiles and longitudinal contours under transmission lines","authors":"R. Maruthi, K. Karunakara, M. K. Kumari, K. Srinivasa, Channakeshava","doi":"10.1109/EMPD.1995.500727","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500727","url":null,"abstract":"EHV and UHV AC transmission lines and electrical equipment produce electric and magnetic fields around their vicinity. AC conductors used for 220 kV and below are usually designed on the basis of current carrying capacity, whereas those for 400 kV and above have to take into account the electromagnetic fields produced by them. The design of EHV and UHV lines should also consider the consequences of the fields on objects and human beings when their levels are beyond certain limits. Because of this, it is necessary to be able to estimate these electromagnetic fields through computations. A program has been developed for computing the electric and magnetic fields around the transmission lines in India. The computed and the measured values of these fields are presented in this paper for the existing lines in Indian systems.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127290681","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500801
G.H. Chen, K. Tseng
This paper presents a high efficiency direct wheel motor drive for electric vehicles (EVs). The proposed motor is a permanent magnet square-wave motor whose rotor with rare earth magnets forms the outside of the motor to be set within each rear wheel tyre to realize the direct drive. The inner stator with its windings is rigidly linked to the suspension and frame structure of the vehicle. In order to achieve the direct drive without any mechanical transmission for EVs, the wheel motor has been designed as a low-speed high-torque motor. The design and optimization of the motor was done with the aid of finite element electromagnetic field analysis using the Maxwell 2D Simulator software. The motor parameters and characteristics can be accurately calculated and predicted in terms of field computation and analysis results. The design procedure of the 6.6 kW, 1000 RPM wheel motor and its technical data are given in this paper.
{"title":"Design of wheel motor using Maxwell 2D simulation","authors":"G.H. Chen, K. Tseng","doi":"10.1109/EMPD.1995.500801","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500801","url":null,"abstract":"This paper presents a high efficiency direct wheel motor drive for electric vehicles (EVs). The proposed motor is a permanent magnet square-wave motor whose rotor with rare earth magnets forms the outside of the motor to be set within each rear wheel tyre to realize the direct drive. The inner stator with its windings is rigidly linked to the suspension and frame structure of the vehicle. In order to achieve the direct drive without any mechanical transmission for EVs, the wheel motor has been designed as a low-speed high-torque motor. The design and optimization of the motor was done with the aid of finite element electromagnetic field analysis using the Maxwell 2D Simulator software. The motor parameters and characteristics can be accurately calculated and predicted in terms of field computation and analysis results. The design procedure of the 6.6 kW, 1000 RPM wheel motor and its technical data are given in this paper.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121915867","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500709
W. Jiang, C. Teo
A hierarchical knowledge-based restoration system which decomposes the bulk power system restoration problems into objective layer and action layer is described. The structure of the knowledge-based system is proposed and various system constraints are considered, and the restoration system is developed using expert system shell G2.
{"title":"A knowledge-based approach for bulk power system restoration","authors":"W. Jiang, C. Teo","doi":"10.1109/EMPD.1995.500709","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500709","url":null,"abstract":"A hierarchical knowledge-based restoration system which decomposes the bulk power system restoration problems into objective layer and action layer is described. The structure of the knowledge-based system is proposed and various system constraints are considered, and the restoration system is developed using expert system shell G2.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124104717","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500811
P. Dash, D. Swain, H. Khincha, A. Liew
The paper presents a new approach to the estimation of voltage and current phasors of a faulted power system by using an adaptive neural network represented by adalines. The neural estimator uses a nonlinear weight adjustment algorithm for the effective rejection of DC offset and noise. The fault apparent resistance, reactance and fault location of a typical transmission line are calculated using the estimated phasors. The results are quite comparable to the Kalman filter approach which requires more computation than the existing approach.
{"title":"Digital protective relaying using an adaptive neural network","authors":"P. Dash, D. Swain, H. Khincha, A. Liew","doi":"10.1109/EMPD.1995.500811","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500811","url":null,"abstract":"The paper presents a new approach to the estimation of voltage and current phasors of a faulted power system by using an adaptive neural network represented by adalines. The neural estimator uses a nonlinear weight adjustment algorithm for the effective rejection of DC offset and noise. The fault apparent resistance, reactance and fault location of a typical transmission line are calculated using the estimated phasors. The results are quite comparable to the Kalman filter approach which requires more computation than the existing approach.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127894537","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500772
G. Anderson, N. Watson, N.P. Arnold, J. Arrillaga
Hybrid stability programs use a transient stability analysis for AC power systems, in conjunction with detailed state variable or EMTP type modelling for fast dynamic devices. This paper presents a new hybrid algorithm that uses optimised techniques based on previously proposed methods. The hybrid provides a useful analysis tool to examine systems incorporating fast dynamic nonlinear components such as HVDC links and FACTS devices.
{"title":"A new hybrid algorithm for analysis of HVDC and FACTS systems","authors":"G. Anderson, N. Watson, N.P. Arnold, J. Arrillaga","doi":"10.1109/EMPD.1995.500772","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500772","url":null,"abstract":"Hybrid stability programs use a transient stability analysis for AC power systems, in conjunction with detailed state variable or EMTP type modelling for fast dynamic devices. This paper presents a new hybrid algorithm that uses optimised techniques based on previously proposed methods. The hybrid provides a useful analysis tool to examine systems incorporating fast dynamic nonlinear components such as HVDC links and FACTS devices.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127576302","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500819
Wanhong Deng, Tek Tjing Lie
This paper presents the development of a mathematical model representation of variable series capacitors which are also known as flexible AC transmission systems (FACTS) in power system economic dispatch. The objective of this research is to find the optimal locations of FACTS devices for improved economic dispatch. The proposed approach is based on the decomposition-coordination method and the network compensation technique. Taking the advantages of accumulated experience in power system optimization and the existence of the optimal power flow (OFF) software, the software development cost for implementing the proposed algorithm is reduced. In this paper, digital simulation studies on small power systems with and without variable series capacitors were conducted respectively. The purpose of these simulation studies is to assess the effectiveness of the proposed algorithm in minimizing the operating cost and enhancing the system performance. The results of the simulation studies and the proposed algorithm are presented and discussed in greater detail.
{"title":"Optimal compensation of variable series capacitors for improved economic dispatch in power systems","authors":"Wanhong Deng, Tek Tjing Lie","doi":"10.1109/EMPD.1995.500819","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500819","url":null,"abstract":"This paper presents the development of a mathematical model representation of variable series capacitors which are also known as flexible AC transmission systems (FACTS) in power system economic dispatch. The objective of this research is to find the optimal locations of FACTS devices for improved economic dispatch. The proposed approach is based on the decomposition-coordination method and the network compensation technique. Taking the advantages of accumulated experience in power system optimization and the existence of the optimal power flow (OFF) software, the software development cost for implementing the proposed algorithm is reduced. In this paper, digital simulation studies on small power systems with and without variable series capacitors were conducted respectively. The purpose of these simulation studies is to assess the effectiveness of the proposed algorithm in minimizing the operating cost and enhancing the system performance. The results of the simulation studies and the proposed algorithm are presented and discussed in greater detail.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128271219","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500753
San-Yi Lee, Wei-Nan Chang, Chi-Jui Wu
A compact control algorithm for reactive power compensation and load balancing with the static VAr compensator (SVC) in three-phase three-wire power systems is developed in this paper. Each phase susceptance of the SVC can be obtained from a very simple function of voltage and power signals which are measured by a three-phase voltage transducer and two single-phase active and reactive power (P-Q) transducers at the load bus. The calculation of compensation susceptances is based on the criterion of a unity power factor and zero sequence currents after compensation. A simulation is made, as the first stage, to show the validity of the proposed compensation algorithm. Then, a laboratory size microcomputer-based SVC, which consists of thyristor-controlled reactors (TCRs) and fixed capacitors (FCs), is designed and implemented. Simulation and experiment results show that the algorithm is very suitable for online control of the SVC which is designed for phase balancing and power factor correction.
{"title":"A compact algorithm for three-phase three-wire system reactive power compensation and load balancing","authors":"San-Yi Lee, Wei-Nan Chang, Chi-Jui Wu","doi":"10.1109/EMPD.1995.500753","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500753","url":null,"abstract":"A compact control algorithm for reactive power compensation and load balancing with the static VAr compensator (SVC) in three-phase three-wire power systems is developed in this paper. Each phase susceptance of the SVC can be obtained from a very simple function of voltage and power signals which are measured by a three-phase voltage transducer and two single-phase active and reactive power (P-Q) transducers at the load bus. The calculation of compensation susceptances is based on the criterion of a unity power factor and zero sequence currents after compensation. A simulation is made, as the first stage, to show the validity of the proposed compensation algorithm. Then, a laboratory size microcomputer-based SVC, which consists of thyristor-controlled reactors (TCRs) and fixed capacitors (FCs), is designed and implemented. Simulation and experiment results show that the algorithm is very suitable for online control of the SVC which is designed for phase balancing and power factor correction.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128314778","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500722
C. Su, Guor-Rurng Lii
This paper develops an optimization method for reliable design of substations. Reliability indices used are failure rate and interruption duration, which are commonly used in the distribution systems. Through applying the proposed method, the optimal reliability indices of apparatus are obtained, which minimize the total cost comprising apparatus investment cost and interruption cost, and also satisfy reliability constraints of load point. Three kinds of interruption cost including initial interruption cost, outage frequency cost and interruption duration cost are considered. The optimization technique employed in this paper to solve the nonlinear programming problems is the generalized reduced gradient (GRG) method. For simplification of computation of large or complex systems, the multi-level hierarchical optimization is applied. It starts by dividing the system into several subsystems, and finds the optimal reliability indices for subsystems. Then by repeatedly taking the previous "subsystem" as the following "system" and the previous "constituent" as the following "subsystem", and applying the GRG method, we can finally find the desired reliability indices for components of the primitive system. To demonstrate the application of the method, a secondary substation of the Taiwan Power Company is taken as an example, computation results of the application example show that the interruption cost is effectively reduced. The proposed method is applicable to existing substation expansion and new substation establishment.
{"title":"Reliability optimization design of distribution systems via multi-level hierarchical procedures and generalized reduced gradient method","authors":"C. Su, Guor-Rurng Lii","doi":"10.1109/EMPD.1995.500722","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500722","url":null,"abstract":"This paper develops an optimization method for reliable design of substations. Reliability indices used are failure rate and interruption duration, which are commonly used in the distribution systems. Through applying the proposed method, the optimal reliability indices of apparatus are obtained, which minimize the total cost comprising apparatus investment cost and interruption cost, and also satisfy reliability constraints of load point. Three kinds of interruption cost including initial interruption cost, outage frequency cost and interruption duration cost are considered. The optimization technique employed in this paper to solve the nonlinear programming problems is the generalized reduced gradient (GRG) method. For simplification of computation of large or complex systems, the multi-level hierarchical optimization is applied. It starts by dividing the system into several subsystems, and finds the optimal reliability indices for subsystems. Then by repeatedly taking the previous \"subsystem\" as the following \"system\" and the previous \"constituent\" as the following \"subsystem\", and applying the GRG method, we can finally find the desired reliability indices for components of the primitive system. To demonstrate the application of the method, a secondary substation of the Taiwan Power Company is taken as an example, computation results of the application example show that the interruption cost is effectively reduced. The proposed method is applicable to existing substation expansion and new substation establishment.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128530349","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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