Pub Date : 2012-03-05DOI: 10.1109/ISGTEurope.2011.6162718
V. Barrera, A. Pavas, J. Meléndez
Power quality assessment of the Bogotá distribution network has been performed using four different statistical methods. Data was collected during two years by CODENSA, the largest Colombian electricity utility. The strategies have been divided as quantitative and qualitative approaches. Quantitative strategies are based on the study of probability density functions as well as the analysis of principal components (PCA). Probability density functions of voltage sag magnitudes have been used to better characterise their occurrence. PCA has been used to improve the analysis of sags based on coordination charts. On the other hand, qualitative approaches are focused on two sag related indices: the sag activity index (SAI index) and the amount of not delivered when the disturbance occurs. Those methods have been applied to assess power quality of 249 substations.
{"title":"Power quality assessment of the Bogotá distribution network focused on voltage sag analysis","authors":"V. Barrera, A. Pavas, J. Meléndez","doi":"10.1109/ISGTEurope.2011.6162718","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162718","url":null,"abstract":"Power quality assessment of the Bogotá distribution network has been performed using four different statistical methods. Data was collected during two years by CODENSA, the largest Colombian electricity utility. The strategies have been divided as quantitative and qualitative approaches. Quantitative strategies are based on the study of probability density functions as well as the analysis of principal components (PCA). Probability density functions of voltage sag magnitudes have been used to better characterise their occurrence. PCA has been used to improve the analysis of sags based on coordination charts. On the other hand, qualitative approaches are focused on two sag related indices: the sag activity index (SAI index) and the amount of not delivered when the disturbance occurs. Those methods have been applied to assess power quality of 249 substations.","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129970688","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 : 2011-12-07DOI: 10.1109/ISGTEurope.2011.6162785
A. Roscoe, C. Bright, S. Galloway, G. Burt
This paper describes intelligent ways in which distributed generation and local loads can be controlled during large system disturbances, using Local Power Controllers. When distributed generation is available, and a system disturbance is detected early enough, the generation can be dispatched, and its output power can be matched as closely as possible to local microgrid demand levels. Priority-based load shedding can be implemented to aid this process. In this state, the local microgrid supports the wider network by relieving the wider network of the micro-grid load. Should grid performance degrade further, the local microgrid can separate itself from the network and maintain power to the most important local loads, re-synchronising to the grid only after more normal performance is regained. Such an intelligent system would be a suitable for hospitals, data centres, or any other industrial facility where there are critical loads. The paper demonstrates the actions of such Local Power Controllers using laboratory experiments at the 10kVA scale.
{"title":"Increasing security of supply by the use of a Local Power Controller during large system disturbances","authors":"A. Roscoe, C. Bright, S. Galloway, G. Burt","doi":"10.1109/ISGTEurope.2011.6162785","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162785","url":null,"abstract":"This paper describes intelligent ways in which distributed generation and local loads can be controlled during large system disturbances, using Local Power Controllers. When distributed generation is available, and a system disturbance is detected early enough, the generation can be dispatched, and its output power can be matched as closely as possible to local microgrid demand levels. Priority-based load shedding can be implemented to aid this process. In this state, the local microgrid supports the wider network by relieving the wider network of the micro-grid load. Should grid performance degrade further, the local microgrid can separate itself from the network and maintain power to the most important local loads, re-synchronising to the grid only after more normal performance is regained. Such an intelligent system would be a suitable for hospitals, data centres, or any other industrial facility where there are critical loads. The paper demonstrates the actions of such Local Power Controllers using laboratory experiments at the 10kVA scale.","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":"12 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116793931","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 : 2011-12-05DOI: 10.1109/ISGTEurope.2011.6162723
A. Kiprakis, Ian Dent, S. Djokic, S. McLaughlin
This paper presents the work program of DESIMAX, a collaborative research project looking at wide-scale implementation of demand side management (DSM) within electricity networks. To fully understand the implications of extended use of DSM, it is important to develop multi-scale models that will be able to capture, predict and demonstrate the response of the power system at time scales ranging from sub-second intervals to periods of years. A multi-sector modeling framework is proposed that includes the physical (electrical) system, the end-user behavior, the economic and environmental models, as well as the set of digital interventions required in order to assist wider and easier implementation of DSM. The proposed modeling framework allows for a holistic approach to DSM integration and is capable of assessing the implications and effects of devised DSM schemes across the entire electricity system.
{"title":"Multi-scale dynamic modeling to maximize demand side management","authors":"A. Kiprakis, Ian Dent, S. Djokic, S. McLaughlin","doi":"10.1109/ISGTEurope.2011.6162723","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162723","url":null,"abstract":"This paper presents the work program of DESIMAX, a collaborative research project looking at wide-scale implementation of demand side management (DSM) within electricity networks. To fully understand the implications of extended use of DSM, it is important to develop multi-scale models that will be able to capture, predict and demonstrate the response of the power system at time scales ranging from sub-second intervals to periods of years. A multi-sector modeling framework is proposed that includes the physical (electrical) system, the end-user behavior, the economic and environmental models, as well as the set of digital interventions required in order to assist wider and easier implementation of DSM. The proposed modeling framework allows for a holistic approach to DSM integration and is capable of assessing the implications and effects of devised DSM schemes across the entire electricity system.","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123556604","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 : 2011-12-05DOI: 10.1109/ISGTEurope.2011.6162742
A. Collin, I. Hernando‐Gil, J. Acosta, Irinel-Sorin Ilie, S. Djokic
This paper, which is the second part of a two-part series, considers the influence of microgeneration technologies on the overall network performance and quality of supply of low-voltage residential customers in future “smart grids”. The paper uses the network models and demand-side management (DSM) scenarios developed in the Part 1 paper to further assess changes in active/reactive power flows, system losses, voltage profiles and harmonic emissions due to the combined effects of implementing microgeneration, energy storage and DSM.
{"title":"Realising the potential of smart grids in LV networks. Part 2: Microgeneration","authors":"A. Collin, I. Hernando‐Gil, J. Acosta, Irinel-Sorin Ilie, S. Djokic","doi":"10.1109/ISGTEurope.2011.6162742","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162742","url":null,"abstract":"This paper, which is the second part of a two-part series, considers the influence of microgeneration technologies on the overall network performance and quality of supply of low-voltage residential customers in future “smart grids”. The paper uses the network models and demand-side management (DSM) scenarios developed in the Part 1 paper to further assess changes in active/reactive power flows, system losses, voltage profiles and harmonic emissions due to the combined effects of implementing microgeneration, energy storage and DSM.","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122906120","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 : 2011-12-05DOI: 10.1109/ISGTEurope.2011.6162681
P. Janssen, T. Sezi, J. Maun
In case of a power system disturbance, main focus of the utility is to keep the duration of the interruption as short as possible. This requires fast identification of the fault location, isolation of the defected components and power supply restoration. To achieve the goal “fast and accurate fault location”, distributed fault recordings can be used. Measurements can be retrieved from substation, reclosers or distributed generator relays. This paper presents a new fault location scheme in distribution systems using distributed voltage and current recordings. The algorithm transfers voltage and current from measurement devices through the faulted line. Fault distance is then calculated using a single- or two-ended fault location method. Statistical errors on phasors and networks parameters are considered to obtain an optimal estimation of the fault location. Standard deviation of the fault distance estimate is also calculated. The performance of the algorithm is verified on a simulated distribution system.
{"title":"Optimal fault location in distribution systems using distributed disturbance recordings","authors":"P. Janssen, T. Sezi, J. Maun","doi":"10.1109/ISGTEurope.2011.6162681","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162681","url":null,"abstract":"In case of a power system disturbance, main focus of the utility is to keep the duration of the interruption as short as possible. This requires fast identification of the fault location, isolation of the defected components and power supply restoration. To achieve the goal “fast and accurate fault location”, distributed fault recordings can be used. Measurements can be retrieved from substation, reclosers or distributed generator relays. This paper presents a new fault location scheme in distribution systems using distributed voltage and current recordings. The algorithm transfers voltage and current from measurement devices through the faulted line. Fault distance is then calculated using a single- or two-ended fault location method. Statistical errors on phasors and networks parameters are considered to obtain an optimal estimation of the fault location. Standard deviation of the fault distance estimate is also calculated. The performance of the algorithm is verified on a simulated distribution system.","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123711331","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 : 2011-12-05DOI: 10.1109/ISGTEurope.2011.6162739
A. Collin, I. Hernando‐Gil, J. Acosta, Irinel-Sorin Ilie, S. Djokic
This paper, which is part one of a two-part series, analyses the influence of demand-side management (DSM) on the overall performance of distribution networks, particularly with respect to the quality of supply of low-voltage residential customers. The paper uses detailed network configurations and load models to assess changes in active/reactive power flows, system losses, voltage profiles and propagation of harmonics due to changes in the load mix as a result of DSM actions. The Part 2 paper will consider the effect of microgeneration technologies on further improvement/ deterioration of network performance.
{"title":"Realising the potential of smart grids in LV networks. Part 1: Demand-side management","authors":"A. Collin, I. Hernando‐Gil, J. Acosta, Irinel-Sorin Ilie, S. Djokic","doi":"10.1109/ISGTEurope.2011.6162739","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162739","url":null,"abstract":"This paper, which is part one of a two-part series, analyses the influence of demand-side management (DSM) on the overall performance of distribution networks, particularly with respect to the quality of supply of low-voltage residential customers. The paper uses detailed network configurations and load models to assess changes in active/reactive power flows, system losses, voltage profiles and propagation of harmonics due to changes in the load mix as a result of DSM actions. The Part 2 paper will consider the effect of microgeneration technologies on further improvement/ deterioration of network performance.","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":"88 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133878838","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/ISGTEurope.2011.6162627
Arno Claassen, S. Rohjans, S. Lehnhoff
This contribution focuses on interoperability in the overall context of Smart Grids. Whereas Smart Grids are understood as the future energy supply system supported by ICT. For the upcoming need for massive data exchange in Smart Grids both syntactic and semantic issues have to be addressed. In terms of data exchange and ICT semantics are covered by electronic data models representing the real world. Communication architectures including communication standards are dealing with the syntactic aspects. One possible solution for those architectures is the paradigm of service-oriented architectures (SOA). The OPC Unified Architecture (UA) implements this paradigm. The UA is maintained by the OPC Foundation and partly standardized as IEC 62541. It describes a server-client-architecture based on abstract services and an abstract information model which can be used to model domain specific data for general data exchange purposes. In this contribution the application feasibility of the UA is shown based on use cases which were modeled by using the inubit process engine and chosen due to suitable Non-Functional Requirements (NFR).
{"title":"Application of the OPC UA for the Smart Grid","authors":"Arno Claassen, S. Rohjans, S. Lehnhoff","doi":"10.1109/ISGTEurope.2011.6162627","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162627","url":null,"abstract":"This contribution focuses on interoperability in the overall context of Smart Grids. Whereas Smart Grids are understood as the future energy supply system supported by ICT. For the upcoming need for massive data exchange in Smart Grids both syntactic and semantic issues have to be addressed. In terms of data exchange and ICT semantics are covered by electronic data models representing the real world. Communication architectures including communication standards are dealing with the syntactic aspects. One possible solution for those architectures is the paradigm of service-oriented architectures (SOA). The OPC Unified Architecture (UA) implements this paradigm. The UA is maintained by the OPC Foundation and partly standardized as IEC 62541. It describes a server-client-architecture based on abstract services and an abstract information model which can be used to model domain specific data for general data exchange purposes. In this contribution the application feasibility of the UA is shown based on use cases which were modeled by using the inubit process engine and chosen due to suitable Non-Functional Requirements (NFR).","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":"15 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":"124263335","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/ISGTEurope.2011.6162671
D. Kamperis, G. Vanalme, W. Kling
Micro-cogeneration units are expected to penetrate the domestic boiler market soon especially in countries with extensive gas network. A high penetration level can lead to problems in passive designed LV networks. The voltage rise across the distribution lines, due to the reverse power flow, seems to be the main limiting factor on the amount of μ-CHPs connected to the LV grid. Meshed networks are believed to incorporate higher level of distributed generators compared to radial networks. However, the possibility of μ-CHPs to operate under different control strategies will also enhance their penetration level and facilitate their integration in a Virtual Power Plant concept. This is shown by steady state simulations performed in a Dutch LV network. The scope of this paper is to illustrate how the network topology and the control strategy of μ-CHPs affect their maximum penetration level and how they can be integrated in a Virtual Power Plant.
{"title":"The ability of a Dutch LV network to incorporate high penetration level of μ-CHPs considering network topology and units control strategy","authors":"D. Kamperis, G. Vanalme, W. Kling","doi":"10.1109/ISGTEurope.2011.6162671","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162671","url":null,"abstract":"Micro-cogeneration units are expected to penetrate the domestic boiler market soon especially in countries with extensive gas network. A high penetration level can lead to problems in passive designed LV networks. The voltage rise across the distribution lines, due to the reverse power flow, seems to be the main limiting factor on the amount of μ-CHPs connected to the LV grid. Meshed networks are believed to incorporate higher level of distributed generators compared to radial networks. However, the possibility of μ-CHPs to operate under different control strategies will also enhance their penetration level and facilitate their integration in a Virtual Power Plant concept. This is shown by steady state simulations performed in a Dutch LV network. The scope of this paper is to illustrate how the network topology and the control strategy of μ-CHPs affect their maximum penetration level and how they can be integrated in a Virtual Power Plant.","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":" 23","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120829569","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/ISGTEurope.2011.6162640
A. Glazunova, I. Kolosok, E. Korkina
State estimation is the most important procedure providing the electric power system control with reliable quality information. The role of state estimation problem is getting more pronounced with transition to a qualitatively new level of technologies and control of power systems based on the wide-area monitoring and control systems (WAMS/WACS). Currently the electric power system (EPS) state estimation methods are developed on the basis of combined application of conventional measurements from SCADA and phasor measurement that are provided by PMU. Practical application of PMUs reveals a number of factors that affect the correctness of their measurements. Therefore, the need arises to verify the PMU measurements. The paper suggests the approaches to validation of PMU measurements on the basis of test equation technique. Consideration is given to the modification of state estimation algorithm by combining the SCADA and PMU measurements.
{"title":"Monitoring of EPS operation by the state estimation methods","authors":"A. Glazunova, I. Kolosok, E. Korkina","doi":"10.1109/ISGTEurope.2011.6162640","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162640","url":null,"abstract":"State estimation is the most important procedure providing the electric power system control with reliable quality information. The role of state estimation problem is getting more pronounced with transition to a qualitatively new level of technologies and control of power systems based on the wide-area monitoring and control systems (WAMS/WACS). Currently the electric power system (EPS) state estimation methods are developed on the basis of combined application of conventional measurements from SCADA and phasor measurement that are provided by PMU. Practical application of PMUs reveals a number of factors that affect the correctness of their measurements. Therefore, the need arises to verify the PMU measurements. The paper suggests the approaches to validation of PMU measurements on the basis of test equation technique. Consideration is given to the modification of state estimation algorithm by combining the SCADA and PMU measurements.","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":"33 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":"125154756","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/ISGTEurope.2011.6162691
Benedict Ruben, A. Cross, D. Strickland, M. Aten, R. Ferris
This project evaluates the benefits of meshing existing 11kV radial networks in order to reduce losses and maximise the connection of low carbon distributed generation. These networks are often arranged as radial feeders with normally-open links between two of the feeders; the link is closed only to enable continuity of supply to an isolated portion of a feeder following a fault on the network. However, this link could also be closed permanently thus operating the network as a meshed topology under non-faulted conditions. The study will look at loss savings and the addition of distributed generation on a typical network under three different scenarios; traditional radial feeders, fixed meshed network and a dynamic meshed network. The networks are compared in terms of feeder losses, capacity, voltage regulation and fault levels.
{"title":"Meshing radial networks at 11kV","authors":"Benedict Ruben, A. Cross, D. Strickland, M. Aten, R. Ferris","doi":"10.1109/ISGTEurope.2011.6162691","DOIUrl":"https://doi.org/10.1109/ISGTEurope.2011.6162691","url":null,"abstract":"This project evaluates the benefits of meshing existing 11kV radial networks in order to reduce losses and maximise the connection of low carbon distributed generation. These networks are often arranged as radial feeders with normally-open links between two of the feeders; the link is closed only to enable continuity of supply to an isolated portion of a feeder following a fault on the network. However, this link could also be closed permanently thus operating the network as a meshed topology under non-faulted conditions. The study will look at loss savings and the addition of distributed generation on a typical network under three different scenarios; traditional radial feeders, fixed meshed network and a dynamic meshed network. The networks are compared in terms of feeder losses, capacity, voltage regulation and fault levels.","PeriodicalId":419250,"journal":{"name":"2011 2nd IEEE PES International Conference and Exhibition on Innovative Smart Grid Technologies","volume":"49 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":"123255815","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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