Pub Date : 2011-03-20DOI: 10.1109/PSCE.2011.5772542
R. Mukerji
Since its inception, the New York Independent System Operator (NYISO) has recognized the importance of allowing demand response resources to maintain reliability and participate in the NYISO's wholesale markets. Currently the NYISO has four Demand Response programs: the Emergency Demand Response Program (EDRP), the ICAP Special Case Resources (SCR) program, the Day Ahead Demand Response Program (DADRP) and the Demand Side Ancillary Services Program (DSASP).
{"title":"Demand response in the NYISO markets","authors":"R. Mukerji","doi":"10.1109/PSCE.2011.5772542","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772542","url":null,"abstract":"Since its inception, the New York Independent System Operator (NYISO) has recognized the importance of allowing demand response resources to maintain reliability and participate in the NYISO's wholesale markets. Currently the NYISO has four Demand Response programs: the Emergency Demand Response Program (EDRP), the ICAP Special Case Resources (SCR) program, the Day Ahead Demand Response Program (DADRP) and the Demand Side Ancillary Services Program (DSASP).","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"198 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124434151","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 : 2011-03-20DOI: 10.1109/PSCE.2011.5772502
R. Green, Lingfeng Wang, Mansoor Alam, C. Singh
State space pruning is a methodology that has been successfully applied to improve the computational efficiency and convergence of Monte Carlo Simulation (MCS) when computing the reliability indices of composite power systems. This methodology increases performance of MCS by pruning state spaces in such a manner that a new state space with a higher density of failure states than the original state space is created. A method that was previously proposed to increase the efficiency of MCS was the use of Population-based Intelligent Search (PIS), specifically Genetic Algorithms (GA), to prune the state space. This paper extends these ideas to another PIS methodology: Binary Particle Swarm Optimization (BPSO). The results of this study show that BPSO is highly effective in pruning the state space and improving the convergence of MCS. This method is tested using the IEEE reliability test system.
{"title":"State space pruning for reliability evaluation using binary particle swarm optimization","authors":"R. Green, Lingfeng Wang, Mansoor Alam, C. Singh","doi":"10.1109/PSCE.2011.5772502","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772502","url":null,"abstract":"State space pruning is a methodology that has been successfully applied to improve the computational efficiency and convergence of Monte Carlo Simulation (MCS) when computing the reliability indices of composite power systems. This methodology increases performance of MCS by pruning state spaces in such a manner that a new state space with a higher density of failure states than the original state space is created. A method that was previously proposed to increase the efficiency of MCS was the use of Population-based Intelligent Search (PIS), specifically Genetic Algorithms (GA), to prune the state space. This paper extends these ideas to another PIS methodology: Binary Particle Swarm Optimization (BPSO). The results of this study show that BPSO is highly effective in pruning the state space and improving the convergence of MCS. This method is tested using the IEEE reliability test system.","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124653537","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 : 2011-03-20DOI: 10.1109/PSCE.2011.5772605
M. Cvetković, M. Ilić
Phasor Measurement Units (PMU) and Flexible AC Transmission Systems (FACTS) have great potential for stabilizing response of the power grid to the large disturbances. A combination of both technologies can result in very powerful near-real time sensing and control capable of monitoring and counteracting the effects of very fast disturbances. In this paper we propose fast switching of FACTS devices which is guaranteed to transiently stabilize the system using very fast and accurate PMU measurements. The nonlinear control law proposed in this paper is based and designed upon understanding the physical system-wide effects of a fault. The control law can be interpreted in terms of controling stored energy flow dynamics and it is also derived using energy-based high gain control methods for nonlinear systems. As such, it is entirely scalable and applicable to any size system. The location of PMUs and the design of systemwide communications for given locations of FACTS devices is directly determined using the designed control law. FACTS control of this type would not be possible without having the accuracy and sampling rate of PMUs.
{"title":"PMU based transient stabilization using FACTS","authors":"M. Cvetković, M. Ilić","doi":"10.1109/PSCE.2011.5772605","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772605","url":null,"abstract":"Phasor Measurement Units (PMU) and Flexible AC Transmission Systems (FACTS) have great potential for stabilizing response of the power grid to the large disturbances. A combination of both technologies can result in very powerful near-real time sensing and control capable of monitoring and counteracting the effects of very fast disturbances. In this paper we propose fast switching of FACTS devices which is guaranteed to transiently stabilize the system using very fast and accurate PMU measurements. The nonlinear control law proposed in this paper is based and designed upon understanding the physical system-wide effects of a fault. The control law can be interpreted in terms of controling stored energy flow dynamics and it is also derived using energy-based high gain control methods for nonlinear systems. As such, it is entirely scalable and applicable to any size system. The location of PMUs and the design of systemwide communications for given locations of FACTS devices is directly determined using the designed control law. FACTS control of this type would not be possible without having the accuracy and sampling rate of PMUs.","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128348966","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 : 2011-03-20DOI: 10.1109/PSCE.2011.5772614
M. Begovic, Insu Kim
Distributed renewable PV generation, whose cost is slowly decreasing towards grid parity, may provide operational benefits in urban feeders: it could level the load curve, improve the voltage profile and reliability and reduce losses across the feeder, improve the transmission capacity margin, as well as provide environmental benefits. The small distributed renewable PV systems are normally not owned, nor operated by the utility; their output and the locations of individual systems, as well as their sizes and operational status, are not precisely known at the planning stage. The high level of uncertainty makes the planning more complex than in conventional distribution networks. Distributed generation and storage units may reduce the impact of faults on customers within their protection zones by creating islands of supply, thus increasing the reliability of service. However, such generation may be power and/or energy limited, and may not be able to exclusively serve their local loads at all times. The paper discusses the issues related to designing the feeders with distributed renewable generation and methodology for analysis of their operation.
{"title":"Distributed renewable PV generation in urban distribution networks","authors":"M. Begovic, Insu Kim","doi":"10.1109/PSCE.2011.5772614","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772614","url":null,"abstract":"Distributed renewable PV generation, whose cost is slowly decreasing towards grid parity, may provide operational benefits in urban feeders: it could level the load curve, improve the voltage profile and reliability and reduce losses across the feeder, improve the transmission capacity margin, as well as provide environmental benefits. The small distributed renewable PV systems are normally not owned, nor operated by the utility; their output and the locations of individual systems, as well as their sizes and operational status, are not precisely known at the planning stage. The high level of uncertainty makes the planning more complex than in conventional distribution networks. Distributed generation and storage units may reduce the impact of faults on customers within their protection zones by creating islands of supply, thus increasing the reliability of service. However, such generation may be power and/or energy limited, and may not be able to exclusively serve their local loads at all times. The paper discusses the issues related to designing the feeders with distributed renewable generation and methodology for analysis of their operation.","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"271 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129151286","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 : 2011-03-20DOI: 10.1109/PSCE.2011.5772531
Le Xu, M. Marshall, Luther Dow
The popularity of plug-in electric vehicles (PEV) is growing quickly and is expected to take a large share in the future automobile market. The integration of PEV may significantly impact electric systems, especially distribution systems. Various PEV impact studies have been undertaken. However, due to the great uncertainty in many crucial assumptions and parameters, it is essential to have a framework that can accommodate various assumptions and can be easily adopted by utilities for their own studies to make mitigation plans. This paper proposes a PEV impact assessment framework, which utilizes cluster analysis to select a small set of representative circuits, carries out the impact study via Monte Carlo simulation on the representative circuits, and then extrapolates the feeder level impact to the system level. The impact study algorithm takes in assumed PEV charging scenarios and run load flow analysis to understand various potential impacts of PEV such as equipment overloading, losses, voltage profile, etc.
{"title":"A framework for assessing the impact of plug-in electric vehicle to distribution systems","authors":"Le Xu, M. Marshall, Luther Dow","doi":"10.1109/PSCE.2011.5772531","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772531","url":null,"abstract":"The popularity of plug-in electric vehicles (PEV) is growing quickly and is expected to take a large share in the future automobile market. The integration of PEV may significantly impact electric systems, especially distribution systems. Various PEV impact studies have been undertaken. However, due to the great uncertainty in many crucial assumptions and parameters, it is essential to have a framework that can accommodate various assumptions and can be easily adopted by utilities for their own studies to make mitigation plans. This paper proposes a PEV impact assessment framework, which utilizes cluster analysis to select a small set of representative circuits, carries out the impact study via Monte Carlo simulation on the representative circuits, and then extrapolates the feeder level impact to the system level. The impact study algorithm takes in assumed PEV charging scenarios and run load flow analysis to understand various potential impacts of PEV such as equipment overloading, losses, voltage profile, etc.","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126998334","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 : 2011-03-20DOI: 10.1109/PSCE.2011.5772600
A. Kusiak, Zijun Zhang
A bi-objective optimization model of power and power changes generated by a wind turbine is discussed in this paper. The model involves two objectives, power maximization and power ramp rate (PRR) minimization. A new constraint for power maximization based on physics and process control theory is introduced. Data-mining algorithms were used to identify the model of power generation from the industrial data collected at a wind farm. The models and constraints derived from the data were integrated to optimize the power itself and the power variability, expressed as the power ramp rate. Due to the nonlinearity and complexity of the optimization model, an artificial immune network algorithm was used to solve it. The optimization results, such as computed operation strategies and the corresponding outputs, are demonstrated and discussed.
{"title":"Optimization of power and its variability with an artificial immune network algorithm","authors":"A. Kusiak, Zijun Zhang","doi":"10.1109/PSCE.2011.5772600","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772600","url":null,"abstract":"A bi-objective optimization model of power and power changes generated by a wind turbine is discussed in this paper. The model involves two objectives, power maximization and power ramp rate (PRR) minimization. A new constraint for power maximization based on physics and process control theory is introduced. Data-mining algorithms were used to identify the model of power generation from the industrial data collected at a wind farm. The models and constraints derived from the data were integrated to optimize the power itself and the power variability, expressed as the power ramp rate. Due to the nonlinearity and complexity of the optimization model, an artificial immune network algorithm was used to solve it. The optimization results, such as computed operation strategies and the corresponding outputs, are demonstrated and discussed.","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130686144","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 : 2011-03-20DOI: 10.1109/PSCE.2011.5772562
T. Jalal, P. Bodger
Since the commencement of the Electricity Market (NZEM) in October 1996, generation expansion in New Zealand is made based on profit anticipation from the wholesale electricity spot price rather than through coordinated planning. This has caused boom and bust cycles in the generation capacity. Energy shortages occurred in 2001, 2003 and 2008. A new model based on System Dynamics (SD) is developed to study these cycles. Its results are compared to the results of the Generation Expansion Model (GEM), developed by the New Zealand Electricity Commission and published in the Statement of Opportunity 2008 (SOO2008). The model is able to identify some capacity cycles that are likely to happen in the future. The analysis is then extended to evaluate whether the cycles will result in energy shortages. The SD model shows that under some future scenarios, New Zealand is susceptible to electricity shortages due to the bust periods in the capacity cycles.
{"title":"Evaluating the impacts of generation capacity cycles in New Zealand","authors":"T. Jalal, P. Bodger","doi":"10.1109/PSCE.2011.5772562","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772562","url":null,"abstract":"Since the commencement of the Electricity Market (NZEM) in October 1996, generation expansion in New Zealand is made based on profit anticipation from the wholesale electricity spot price rather than through coordinated planning. This has caused boom and bust cycles in the generation capacity. Energy shortages occurred in 2001, 2003 and 2008. A new model based on System Dynamics (SD) is developed to study these cycles. Its results are compared to the results of the Generation Expansion Model (GEM), developed by the New Zealand Electricity Commission and published in the Statement of Opportunity 2008 (SOO2008). The model is able to identify some capacity cycles that are likely to happen in the future. The analysis is then extended to evaluate whether the cycles will result in energy shortages. The SD model shows that under some future scenarios, New Zealand is susceptible to electricity shortages due to the bust periods in the capacity cycles.","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127848089","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 : 2011-03-20DOI: 10.1109/PSCE.2011.5772584
A. Escobar, M. Saadeh, J. Balda, J. Bourne, Y. Feng, H. Mantooth
High short-circuit currents can cause equipment failures that conventional protective devices may not avoid. Alternatively, solid-state fault current limiters (SSFCL) are designed to limit high levels of short circuit currents, in particular, within quarter cycle. However, the SSFCL may cause sensor and protection equipment malfunction; this may lead to mis-coordination and false tripping between existing protective devices, and thus reduce system reliability. This paper addresses a methodology to coordinate conventional protective devices and a thyristor-based SSFCL in a distribution system, and analyzes potential coordination issues and effectiveness of the proposed method. It also describes an approach to produce SSFCL time-current characteristic curves (TCC) and their use in protection coordination studies. Lastly, the analysis includes SSFCL to recloser and SSFCL to fuse coordination cases and includes simulation results of several fault scenarios. Lastly, the paper describes.
{"title":"A methodology to coordinate solid-state fault current limiters with conventional protective devices","authors":"A. Escobar, M. Saadeh, J. Balda, J. Bourne, Y. Feng, H. Mantooth","doi":"10.1109/PSCE.2011.5772584","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772584","url":null,"abstract":"High short-circuit currents can cause equipment failures that conventional protective devices may not avoid. Alternatively, solid-state fault current limiters (SSFCL) are designed to limit high levels of short circuit currents, in particular, within quarter cycle. However, the SSFCL may cause sensor and protection equipment malfunction; this may lead to mis-coordination and false tripping between existing protective devices, and thus reduce system reliability. This paper addresses a methodology to coordinate conventional protective devices and a thyristor-based SSFCL in a distribution system, and analyzes potential coordination issues and effectiveness of the proposed method. It also describes an approach to produce SSFCL time-current characteristic curves (TCC) and their use in protection coordination studies. Lastly, the analysis includes SSFCL to recloser and SSFCL to fuse coordination cases and includes simulation results of several fault scenarios. Lastly, the paper describes.","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129259741","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 : 2011-03-20DOI: 10.1109/PSCE.2011.5772554
E. Farantatos, Renke Huang, G. Cokkinides, A. Meliopoulos
A state estimation tool is presented which is suitable for distribution system real time monitoring. The tool is considered to be a critical component of a smart grid infrastructure that will enable modernization of the distribution grid. The proposed estimator is advantageous compared to currently available estimators for two reasons. First, it is based on a three phase physical model of the distribution system. Moreover, it utilizes synchronized measurements available from a novel proposed device (UGPSSM). The synchronized measurement set combined with conventional non-synchronized measurements from SCADA systems results in improved solution and convergence speed. Reporting and visualization tools are also developed in order to make it a user friendly tool for the operators in the DMS. The state estimator provides the operator with a highly accurate real time model of the distribution system that can be used in various applications including Volt/Var control, load levelization and reliability enhancement.
{"title":"Implementation of a 3-phase state estimation tool suitable for advanced distribution management systems","authors":"E. Farantatos, Renke Huang, G. Cokkinides, A. Meliopoulos","doi":"10.1109/PSCE.2011.5772554","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772554","url":null,"abstract":"A state estimation tool is presented which is suitable for distribution system real time monitoring. The tool is considered to be a critical component of a smart grid infrastructure that will enable modernization of the distribution grid. The proposed estimator is advantageous compared to currently available estimators for two reasons. First, it is based on a three phase physical model of the distribution system. Moreover, it utilizes synchronized measurements available from a novel proposed device (UGPSSM). The synchronized measurement set combined with conventional non-synchronized measurements from SCADA systems results in improved solution and convergence speed. Reporting and visualization tools are also developed in order to make it a user friendly tool for the operators in the DMS. The state estimator provides the operator with a highly accurate real time model of the distribution system that can be used in various applications including Volt/Var control, load levelization and reliability enhancement.","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126930519","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 : 2011-03-20DOI: 10.1109/PSCE.2011.5772590
Xing Liu, A. Thirumalai, G. Karady
This paper presents the design and implementation of a very fast pilot protection scheme for the FREEDM∗ system, which is the next generation distribution system. This system is subjected to a line fault. The designed pilot protection system makes time-synchronized measurements. The measurements are converted to digital format, time stamped and transmitted to the computer. The computer compares these measurements and sends a trip signal to the electronic circuit breaker based on the location of the fault. The comparison is done utilizing a protection algorithm for the pilot protection scheme and the over current protection scheme. Since the whole system is based on digital signal, it is much faster compared to the conventional protection system. The hardware implementation of the system and simulation of the protection algorithm is discussed in detail.
{"title":"Design and development of an ultra fast pilot protection","authors":"Xing Liu, A. Thirumalai, G. Karady","doi":"10.1109/PSCE.2011.5772590","DOIUrl":"https://doi.org/10.1109/PSCE.2011.5772590","url":null,"abstract":"This paper presents the design and implementation of a very fast pilot protection scheme for the FREEDM∗ system, which is the next generation distribution system. This system is subjected to a line fault. The designed pilot protection system makes time-synchronized measurements. The measurements are converted to digital format, time stamped and transmitted to the computer. The computer compares these measurements and sends a trip signal to the electronic circuit breaker based on the location of the fault. The comparison is done utilizing a protection algorithm for the pilot protection scheme and the over current protection scheme. Since the whole system is based on digital signal, it is much faster compared to the conventional protection system. The hardware implementation of the system and simulation of the protection algorithm is discussed in detail.","PeriodicalId":120665,"journal":{"name":"2011 IEEE/PES Power Systems Conference and Exposition","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115646353","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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