Pub Date : 2011-12-01DOI: 10.1109/ICEAS.2011.6147132
R. Sharma, P. Samantaray, D. Mohanty, P. Rout
The economic and environmental dispatch problem is formulated as a Non-linear constrained multi-objective problem with competing and non-commensurable objectives of fuel cost and emission. This paper presents a new multi-objective differential evolution algorithm. Initially, a non dominated sorting genetic algorithm is employed to obtain a set of pareto solutions followed by Multi-objective differential evolution algorithm and its corresponding set of pareto solution. The proposed algorithm has been tested on a forty unit test system to illustrate the analysis. The results demonstrate the capabilities of the proposed Multi-objective differential evolution technique to generate the set of well-distributed Pareto-optimal solutions and also reflects its superiority in terms of diversity of the pareto-optimal set. The simulation results obtained from the proposed approach are compared with the NSGA-II method.
{"title":"Environmental economic load dispatch using multi-objective differential evolution algorithm","authors":"R. Sharma, P. Samantaray, D. Mohanty, P. Rout","doi":"10.1109/ICEAS.2011.6147132","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147132","url":null,"abstract":"The economic and environmental dispatch problem is formulated as a Non-linear constrained multi-objective problem with competing and non-commensurable objectives of fuel cost and emission. This paper presents a new multi-objective differential evolution algorithm. Initially, a non dominated sorting genetic algorithm is employed to obtain a set of pareto solutions followed by Multi-objective differential evolution algorithm and its corresponding set of pareto solution. The proposed algorithm has been tested on a forty unit test system to illustrate the analysis. The results demonstrate the capabilities of the proposed Multi-objective differential evolution technique to generate the set of well-distributed Pareto-optimal solutions and also reflects its superiority in terms of diversity of the pareto-optimal set. The simulation results obtained from the proposed approach are compared with the NSGA-II method.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127371490","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147105
A. Paul
Continuous evolution in process and in equipment in arc welding improves compatibility in energy domain. It helps optimize resources such as energy, materials, labor etc, and yield desired productivity and improved quality engineering goals. Modern inverter technology provides multitude of benefits virtually to each entity associated with the process. Efficiency, settling time of output variables and compactness and light weight are major pre-requisites of arc welding equipment. They are all achieved if switching frequency of inverter is kept high. Generally, higher switching frequency is achieved through soft switching. This paper elaborates that input-material-sensitive hard-switched topology is functionally superior to soft-switched topologies and generate superior design for manufacturability issues. It achieves power density ideal for welding power range.
{"title":"Welding inverter for optimal arc characteristics is laterally more sensitive to input materials","authors":"A. Paul","doi":"10.1109/ICEAS.2011.6147105","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147105","url":null,"abstract":"Continuous evolution in process and in equipment in arc welding improves compatibility in energy domain. It helps optimize resources such as energy, materials, labor etc, and yield desired productivity and improved quality engineering goals. Modern inverter technology provides multitude of benefits virtually to each entity associated with the process. Efficiency, settling time of output variables and compactness and light weight are major pre-requisites of arc welding equipment. They are all achieved if switching frequency of inverter is kept high. Generally, higher switching frequency is achieved through soft switching. This paper elaborates that input-material-sensitive hard-switched topology is functionally superior to soft-switched topologies and generate superior design for manufacturability issues. It achieves power density ideal for welding power range.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121553322","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147154
S. Kamboj, R. Dahiya
Dynamic Thermal Line Rating (DTLR) is used to monitor and dynamically upgrade the existing power lines. The overhead conductor sag measurements using GPS has been used to evaluate DTLR in the present paper. GPS receiver BT359 has been used to measure overhead conductor sag of 440V power distribution line and DTLR has been determined at different air temperatures. The inherent error in raw altitude measurements obtained by GPS has been reduced using Least Square parameter estimation and wavelet analysis to obtain more accurate altitude measurements.
DTLR (Dynamic Thermal Line Rating)是一种对现有电力线路进行监测和动态升级的技术。本文利用GPS测量架空导线垂度来评价DTLR。利用GPS接收机BT359测量了440V配电线路架空导线垂度，确定了不同气温下的DTLR。利用最小二乘参数估计和小波分析方法对GPS原始高度测量结果的固有误差进行了减小，得到了更精确的高度测量结果。
{"title":"Evaluation of DTLR of power distribution line from sag measured using GPS","authors":"S. Kamboj, R. Dahiya","doi":"10.1109/ICEAS.2011.6147154","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147154","url":null,"abstract":"Dynamic Thermal Line Rating (DTLR) is used to monitor and dynamically upgrade the existing power lines. The overhead conductor sag measurements using GPS has been used to evaluate DTLR in the present paper. GPS receiver BT359 has been used to measure overhead conductor sag of 440V power distribution line and DTLR has been determined at different air temperatures. The inherent error in raw altitude measurements obtained by GPS has been reduced using Least Square parameter estimation and wavelet analysis to obtain more accurate altitude measurements.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114908059","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147171
S. Kirmani, M. Jamil, M. Rizwan
The appropriate location of distributed generation (DG) is very important for loss reduction in a radial distribution system. In this paper a methodology for determining the optimum size and location for installing the solar photovoltaic (SPV) based DG system for supplying the active power at the node in a radial distribution system for loss reduction is presented. The objective of this paper is to apply heuristic search strategies to determine the node for the appropriate placement of DG. In heuristic approach, a critical node, called sensitive node is selected based upon maximum power losses caused for installing DG system. This method ensures that voltage constraints are met. This heuristic approach is useful for large distribution system and can be useful for online implementation. Test results have been tested on IEEE-33 bus system and presented.
{"title":"Optimal placement of SPV based DG system for loss reduction in radial distribution network using heuristic search strategies","authors":"S. Kirmani, M. Jamil, M. Rizwan","doi":"10.1109/ICEAS.2011.6147171","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147171","url":null,"abstract":"The appropriate location of distributed generation (DG) is very important for loss reduction in a radial distribution system. In this paper a methodology for determining the optimum size and location for installing the solar photovoltaic (SPV) based DG system for supplying the active power at the node in a radial distribution system for loss reduction is presented. The objective of this paper is to apply heuristic search strategies to determine the node for the appropriate placement of DG. In heuristic approach, a critical node, called sensitive node is selected based upon maximum power losses caused for installing DG system. This method ensures that voltage constraints are met. This heuristic approach is useful for large distribution system and can be useful for online implementation. Test results have been tested on IEEE-33 bus system and presented.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133614506","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147078
A. K. Mishra, M. Pathak, S. Das
This paper deals with the analysis, design and analog based hardware implementation of three different topologies of high frequency isolated AC-DC converters in discontinuous current mode (DCM) of operation for power factor correction and output voltage regulation. These switching converters are designed for low power rating and low output voltage, typically 20.25 W with 13.5 V in DCM operation. Modelling and simulation is carried out in a standard PSIM software environment. Laboratory prototypes of the proposed converters in DCM operation are developed and test results are presented to compare with the simulation results.
{"title":"Isolated converter topologies for power factor correction — A comparison","authors":"A. K. Mishra, M. Pathak, S. Das","doi":"10.1109/ICEAS.2011.6147078","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147078","url":null,"abstract":"This paper deals with the analysis, design and analog based hardware implementation of three different topologies of high frequency isolated AC-DC converters in discontinuous current mode (DCM) of operation for power factor correction and output voltage regulation. These switching converters are designed for low power rating and low output voltage, typically 20.25 W with 13.5 V in DCM operation. Modelling and simulation is carried out in a standard PSIM software environment. Laboratory prototypes of the proposed converters in DCM operation are developed and test results are presented to compare with the simulation results.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132718496","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147211
B. Khaki, A. Sharaf, S. H. Mousavi, N. Noroozi, A. Seifi
This paper proposes an adaptive variable-structure control scheme for a three-phase PWM converter under unbalanced conditions. The controller regulates the DC output of PWM converter in presence of unknown disturbance and uncertainty in model parameters of the converter. Using differential geometric tools, the system is transformed to a normal form. Then an adaptive control scheme is designed to regulate the output of the transformed system. The stability of the proposed controller is proved using the Lyapunov theory. Simulation results illustrate the effectiveness of the proposed method.
{"title":"Adaptive control of DC link voltage of PWM VSC rectifier under unbalanced voltage source and uncertain parameters","authors":"B. Khaki, A. Sharaf, S. H. Mousavi, N. Noroozi, A. Seifi","doi":"10.1109/ICEAS.2011.6147211","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147211","url":null,"abstract":"This paper proposes an adaptive variable-structure control scheme for a three-phase PWM converter under unbalanced conditions. The controller regulates the DC output of PWM converter in presence of unknown disturbance and uncertainty in model parameters of the converter. Using differential geometric tools, the system is transformed to a normal form. Then an adaptive control scheme is designed to regulate the output of the transformed system. The stability of the proposed controller is proved using the Lyapunov theory. Simulation results illustrate the effectiveness of the proposed method.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131678314","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147125
A. Moharana, R. Varma
This paper presents a study of subsynchronous mode instability in Induction Generator (IG) based wind farm connected to a series compensated transmission line. The IEEE First SSR benchmark system is modified by replacing the synchronous generator with an aggregated wind farm. A small signal stability analysis is carried out to detect the instability analytically and then results are validated through a detailed electromagnetic transient simulation using PSCAD/EMTDC. Two types of studies are performed for the small signal analysis. First, a linearized state space model is developed for the eigenvalue calculation. Then, a simple equivalent circuit model is developed for the resonant speed analysis. From the equivalent circuit model, two resonant speeds - upper resonant speed (URS) and lower resonant speed (LRS), are obtained. If the post fault speed of the aggregated generator comes close or enters in the band within these two resonant speeds, the induction generator may become unstable. The performance of the aggregated wind farm model is validated with a distributed wind farm model. It is shown that the wind generator may experience SSR if the fault occurs at the terminals of the wind farm even at a realistic level of series compensation.
本文研究了与串联补偿输电线路连接的感应发电机(IG)风电场的次同步模式失稳问题。通过将同步发电机替换为聚合风电场，改进了IEEE First SSR基准系统。通过小信号稳定性分析，对系统的不稳定性进行了分析检测，并利用PSCAD/EMTDC进行了详细的电磁瞬变仿真，对结果进行了验证。对小信号分析进行了两种类型的研究。首先，建立了一个线性化的状态空间模型，用于特征值的计算。然后，建立了一个简单的等效电路模型来分析谐振速度。从等效电路模型出发，得到了两个谐振速度——上谐振速度(URS)和下谐振速度(LRS)。如果聚合发电机的后故障速度接近或进入这两个谐振速度范围内，则感应发电机可能会变得不稳定。用分布式风电场模型验证了聚合风电场模型的性能。结果表明，即使在实际的串联补偿水平下，如果故障发生在风电场的末端，风力发电机也可能发生SSR。
{"title":"Instability in induction generator based wind farms connected to series compensated transmission lines","authors":"A. Moharana, R. Varma","doi":"10.1109/ICEAS.2011.6147125","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147125","url":null,"abstract":"This paper presents a study of subsynchronous mode instability in Induction Generator (IG) based wind farm connected to a series compensated transmission line. The IEEE First SSR benchmark system is modified by replacing the synchronous generator with an aggregated wind farm. A small signal stability analysis is carried out to detect the instability analytically and then results are validated through a detailed electromagnetic transient simulation using PSCAD/EMTDC. Two types of studies are performed for the small signal analysis. First, a linearized state space model is developed for the eigenvalue calculation. Then, a simple equivalent circuit model is developed for the resonant speed analysis. From the equivalent circuit model, two resonant speeds - upper resonant speed (URS) and lower resonant speed (LRS), are obtained. If the post fault speed of the aggregated generator comes close or enters in the band within these two resonant speeds, the induction generator may become unstable. The performance of the aggregated wind farm model is validated with a distributed wind farm model. It is shown that the wind generator may experience SSR if the fault occurs at the terminals of the wind farm even at a realistic level of series compensation.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133385469","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147110
A. Mohapatra, M. K. Mallick, B. K. Panigrahi, Z. Cui, S. Hong
In a deregulated power industry, accurate short term load forecasting (STLF) and price forecasting (STPF) is a key issue in daily power market. The load forecasting helps in unit commitment as well as in economic scheduling of the generators. The price forecasting helps an electric utility to make important decisions like generation of electric power, bidding for generation, price switching and infrastructure development. Price forecasting is very much useful for energy suppliers, ISOs and other participants in electric generation, transmission and distribution. This paper presents a hybrid approach for the STLF and STPF. The time series data pertaining to load / price is decomposed into various decomposition levels by the use of Wavelet Transform (WT) and each level obtained by this process is predicted using Artificial Neural Network (ANN). The performance of the proposed hybrid model is validated using New Delhi load data and Ontario electricity price data.
{"title":"A hybrid approach for short term electricity price and load forecasting","authors":"A. Mohapatra, M. K. Mallick, B. K. Panigrahi, Z. Cui, S. Hong","doi":"10.1109/ICEAS.2011.6147110","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147110","url":null,"abstract":"In a deregulated power industry, accurate short term load forecasting (STLF) and price forecasting (STPF) is a key issue in daily power market. The load forecasting helps in unit commitment as well as in economic scheduling of the generators. The price forecasting helps an electric utility to make important decisions like generation of electric power, bidding for generation, price switching and infrastructure development. Price forecasting is very much useful for energy suppliers, ISOs and other participants in electric generation, transmission and distribution. This paper presents a hybrid approach for the STLF and STPF. The time series data pertaining to load / price is decomposed into various decomposition levels by the use of Wavelet Transform (WT) and each level obtained by this process is predicted using Artificial Neural Network (ANN). The performance of the proposed hybrid model is validated using New Delhi load data and Ontario electricity price data.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131831055","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147088
S. Mishra, P. Sekhar
This paper proposes an effective control strategy for a single-stage, three-phase PV system, supplying local load and integrated with the grid. Maximum power tracking is achieved with interleaved inner current control loop and outer voltage control loop. The output of PV generator is processed by the voltage source converter, a well established dc/ac converter. But these converter systems are highly non linear and coupled. Since the conventional PI controller will not give the satisfactory performance for the changing operating conditions and uncertain load changes, the feedback linearization scheme has been formulated. Sliding mode control technique has been incorporated in the feedback linearized control to address the issues of uncertainty and to add robustness to the control algorithm. The developed control algorithm is tested for the maximum power extraction at different insolations, controlling the dc/ac converter as an ancillary service to supply reactive power, load uncertainties and finally for variable grid frequency within a small band.
{"title":"Sliding mode based feedback linearizing controller for a PV system to improve the performance under grid frequency variation","authors":"S. Mishra, P. Sekhar","doi":"10.1109/ICEAS.2011.6147088","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147088","url":null,"abstract":"This paper proposes an effective control strategy for a single-stage, three-phase PV system, supplying local load and integrated with the grid. Maximum power tracking is achieved with interleaved inner current control loop and outer voltage control loop. The output of PV generator is processed by the voltage source converter, a well established dc/ac converter. But these converter systems are highly non linear and coupled. Since the conventional PI controller will not give the satisfactory performance for the changing operating conditions and uncertain load changes, the feedback linearization scheme has been formulated. Sliding mode control technique has been incorporated in the feedback linearized control to address the issues of uncertainty and to add robustness to the control algorithm. The developed control algorithm is tested for the maximum power extraction at different insolations, controlling the dc/ac converter as an ancillary service to supply reactive power, load uncertainties and finally for variable grid frequency within a small band.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122547240","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147139
P. M. Pradhan
A cognitive radio engine adapts its radio parameters using metaheauristic learning algorithms in order to satisfy certain objectives in a radio environment. In this study, three evolutionary algorithms are used for optimizing the predefined fitness functions in the time varying wireless environment. The performances of genetic algorithm, particle swarm optimization and artificial bee colony algorithm are analysed in different modes of operation and in presence of spectral interference. The simulation results are compared using convergence characteristics and two statistical metrics.
{"title":"Design of cognitive radio engine using artificial bee colony algorithm","authors":"P. M. Pradhan","doi":"10.1109/ICEAS.2011.6147139","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147139","url":null,"abstract":"A cognitive radio engine adapts its radio parameters using metaheauristic learning algorithms in order to satisfy certain objectives in a radio environment. In this study, three evolutionary algorithms are used for optimizing the predefined fitness functions in the time varying wireless environment. The performances of genetic algorithm, particle swarm optimization and artificial bee colony algorithm are analysed in different modes of operation and in presence of spectral interference. The simulation results are compared using convergence characteristics and two statistical metrics.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121446000","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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