Pub Date : 2012-05-07DOI: 10.1109/TDC.2012.6281681
C. Schauder
Photovoltaic (PV) inverters may be subject to different standards and interconnection requirements, depending on their size and interconnection point. PV plants connected at transmission voltage levels may be expected to ride through faults and other disturbances, as expressed in FERC Order 661-A for wind power plants. Islanding detection is not necessary, because customers are not directly served from these plants. On the other hand, PV units connected to distribution feeders are expected to trip automatically during voltage and frequency excursions, as expressed in IEEE Std. 1547. Distribution-connected PV inverters have islanding detection that is designed to meet UL 1741. These conflicting requirements may appear as "wind vs. solar" or "transmission vs. distribution" viewpoints. The impacts on utility-scale PV inverter design and specification are discussed.
{"title":"Impact of FERC 661-A and IEEE 1547 on Photovoltaic inverter design","authors":"C. Schauder","doi":"10.1109/TDC.2012.6281681","DOIUrl":"https://doi.org/10.1109/TDC.2012.6281681","url":null,"abstract":"Photovoltaic (PV) inverters may be subject to different standards and interconnection requirements, depending on their size and interconnection point. PV plants connected at transmission voltage levels may be expected to ride through faults and other disturbances, as expressed in FERC Order 661-A for wind power plants. Islanding detection is not necessary, because customers are not directly served from these plants. On the other hand, PV units connected to distribution feeders are expected to trip automatically during voltage and frequency excursions, as expressed in IEEE Std. 1547. Distribution-connected PV inverters have islanding detection that is designed to meet UL 1741. These conflicting requirements may appear as \"wind vs. solar\" or \"transmission vs. distribution\" viewpoints. The impacts on utility-scale PV inverter design and specification are discussed.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"6 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115653054","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 : 2012-05-07DOI: 10.1109/TDC.2012.6281633
M. Bradt, B. Badrzadeh, E. Camm, D. Mueller, J. Schoene, T. Siebert, T. Smith, M. Starke, R. Walling
This paper presents a summary of the most important issues with respect to harmonics and resonances within wind power plants. An introduction is given to provide an overview of the various power quality related issues encountered when designing, commissioning, or operating a wind power plant, as well as typical characteristics of the components associated with wind power plants. The many variables, which influence harmonics and resonance in wind power plants, will be described with respect to analysis methods, avoidance, mitigation, and compliance with IEEE Std 519–1992 recommended practices.
{"title":"Harmonics and resonance issues in wind power plants","authors":"M. Bradt, B. Badrzadeh, E. Camm, D. Mueller, J. Schoene, T. Siebert, T. Smith, M. Starke, R. Walling","doi":"10.1109/TDC.2012.6281633","DOIUrl":"https://doi.org/10.1109/TDC.2012.6281633","url":null,"abstract":"This paper presents a summary of the most important issues with respect to harmonics and resonances within wind power plants. An introduction is given to provide an overview of the various power quality related issues encountered when designing, commissioning, or operating a wind power plant, as well as typical characteristics of the components associated with wind power plants. The many variables, which influence harmonics and resonance in wind power plants, will be described with respect to analysis methods, avoidance, mitigation, and compliance with IEEE Std 519–1992 recommended practices.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"360 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128610170","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 : 2012-05-07DOI: 10.1109/TDC.2012.6281620
M. Bradt, W. Dilling, B. Lanz, K. Louis, T. Nicolai, M. Starke
Complete testing and commissioning of the wind plant collector system is a critical step to ensure all equipment and systems are in proper working order prior to system energization and operation. In addition a comprehensive test agenda will ensure baseline data is available for comparing with future test data obtained during normally scheduled maintenance outages. This paper provides a thorough description and methodology for complete testing and commissioning of the wind plant medium voltage collector system and the equipment internal to the wind turbine itself.
{"title":"Wind power plant testing and commissioning","authors":"M. Bradt, W. Dilling, B. Lanz, K. Louis, T. Nicolai, M. Starke","doi":"10.1109/TDC.2012.6281620","DOIUrl":"https://doi.org/10.1109/TDC.2012.6281620","url":null,"abstract":"Complete testing and commissioning of the wind plant collector system is a critical step to ensure all equipment and systems are in proper working order prior to system energization and operation. In addition a comprehensive test agenda will ensure baseline data is available for comparing with future test data obtained during normally scheduled maintenance outages. This paper provides a thorough description and methodology for complete testing and commissioning of the wind plant medium voltage collector system and the equipment internal to the wind turbine itself.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114482879","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 : 2012-05-07DOI: 10.1109/TDC.2012.6281639
B. Badrzadeh, M. Bradt, N. Castillo, R. Janakiraman, R. Kennedy, S. Klein, T. Smith, L. Vargas
This paper discusses the range of application for SCADA and control systems in a wind power plant, the most important SCADA and control system considerations, and contractual requirements for SCADA and control systems.
{"title":"Wind power plant SCADA and controls","authors":"B. Badrzadeh, M. Bradt, N. Castillo, R. Janakiraman, R. Kennedy, S. Klein, T. Smith, L. Vargas","doi":"10.1109/TDC.2012.6281639","DOIUrl":"https://doi.org/10.1109/TDC.2012.6281639","url":null,"abstract":"This paper discusses the range of application for SCADA and control systems in a wind power plant, the most important SCADA and control system considerations, and contractual requirements for SCADA and control systems.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121198445","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 : 2012-05-07DOI: 10.1109/TDC.2012.6281597
Dean H. Miller, J. Niemira
The paper discusses design considerations of wind powered generating plants that require knowledge of the fault current contribution of the generators. To provide context, the paper includes brief summary of typical design of the electrical collection and interconnect systems of wind power plants. The impact of fault current contribution on equipment selection is discussed. Common protective relaying practices are discussed and the impacts of fault contributions on setting and selectivity of protective relaying systems are discussed.
{"title":"Fault contribution considerations for wind plant system design and power system protection issues","authors":"Dean H. Miller, J. Niemira","doi":"10.1109/TDC.2012.6281597","DOIUrl":"https://doi.org/10.1109/TDC.2012.6281597","url":null,"abstract":"The paper discusses design considerations of wind powered generating plants that require knowledge of the fault current contribution of the generators. To provide context, the paper includes brief summary of typical design of the electrical collection and interconnect systems of wind power plants. The impact of fault current contribution on equipment selection is discussed. Common protective relaying practices are discussed and the impacts of fault contributions on setting and selectivity of protective relaying systems are discussed.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123283177","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 : 2012-05-01DOI: 10.1109/TDC.2012.6281618
W. Dilling
Wind and solar power plants may be subject to different standards and interconnection requirements, depending on their size, geographic location, interconnection point and other factors. The National Electrical Safety Code (NESC) applies to electric supply facilities, while the National Electrical Code (NEC) governs utilization facilities. NESC applies on the utility side of the service point, while NEC applies on the customer side of the service point. In some jurisdictions, there may be uncertainty over which code applies to customer-owned generation like wind and solar plants. The engineering and construction implications of this difference are discussed.
{"title":"Impact of NEC and NESC on wind and solar plants","authors":"W. Dilling","doi":"10.1109/TDC.2012.6281618","DOIUrl":"https://doi.org/10.1109/TDC.2012.6281618","url":null,"abstract":"Wind and solar power plants may be subject to different standards and interconnection requirements, depending on their size, geographic location, interconnection point and other factors. The National Electrical Safety Code (NESC) applies to electric supply facilities, while the National Electrical Code (NEC) governs utilization facilities. NESC applies on the utility side of the service point, while NEC applies on the customer side of the service point. In some jurisdictions, there may be uncertainty over which code applies to customer-owned generation like wind and solar plants. The engineering and construction implications of this difference are discussed.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124321889","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 : 2012-03-01DOI: 10.1109/MPE.2014.2322296
R. Podmore, R. Larsen, H. Louie, Brian Waldron
This paper describes efforts by the IEEE PES Community Solutions Initiative (CSI) to provide reliable electricity to the 1.6 billion low income people who do not have access to electric light. The Community Solutions Initiative is a virtual community of professionals from a wide variety of backgrounds who are providing largely pro-bono efforts to design, develop, deliver and promote sustainable energy solutions for developing communities. The CSI Community Charging Station (CCS) is designed to charge batteries that are transported to and from their customers' home or business sites. The CCS can be based upon some combination of solar, wind, biogas, biodiesel and / or human powered generation. In the short time since CSI was formed in April 2010 several instances of the CCS have been developed. The CSI LightCycle is a 60 watt pedal powered generator. Two and half hours of daily pedaling can provide four hours of reading quality light for 100 homes. Home owners can buy a locally made LED reading lamp for $1 and have their batteries charged for around $1 per month. The goal is to make the choice for electric light so affordable that home owners will not have to think twice about converting from expensive, unsafe and unhealthy cancerous kerosene. The CSI Solar Trailer is a 1.4 kW charging station with six 235 watt PV solar panels and four large 245 Amp Hour local storage batteries. The Solar Trailer has 20 parallel controllers for charging portable 12 volt home batteries. The Solar Trailer is sized to support 40 homes each with 100 watt hours of daily consumption. With IEEE funding, three pilot systems are being built for installation in Haiti. The open source 10' diameter wind turbine built by the CSI IEEE PES and EWB-USA Seattle Team provides 700 watts in 22 mph wind and costs less than $500 excluding the tower. An effort to build low cost bamboo wind turbine towers is underway. The CCS can be used to charge a range of batteries sizes and types. Open source designs are provided so that local businesses / entrepreneurs can assemble simple but highly effective LED based flashlights, desk/task lamps and ambient / room lamps for a few dollars; excluding battery costs. The CSI products are all based on an open Sustainable Energy Reference Architecture (SERA) so that there is compatibility in all interfaces and maximum commonality of components. The CSI family of products conforms to the criteria defined by Paul Polak; they are extremely affordable and highly miniaturized but infinitely scalable. It now appears that it is a reasonable goal to ensure that the entire world can have access to safe, reliable electric light by the year 2020.
{"title":"Affordable energy solutions for developing communities","authors":"R. Podmore, R. Larsen, H. Louie, Brian Waldron","doi":"10.1109/MPE.2014.2322296","DOIUrl":"https://doi.org/10.1109/MPE.2014.2322296","url":null,"abstract":"This paper describes efforts by the IEEE PES Community Solutions Initiative (CSI) to provide reliable electricity to the 1.6 billion low income people who do not have access to electric light. The Community Solutions Initiative is a virtual community of professionals from a wide variety of backgrounds who are providing largely pro-bono efforts to design, develop, deliver and promote sustainable energy solutions for developing communities. The CSI Community Charging Station (CCS) is designed to charge batteries that are transported to and from their customers' home or business sites. The CCS can be based upon some combination of solar, wind, biogas, biodiesel and / or human powered generation. In the short time since CSI was formed in April 2010 several instances of the CCS have been developed. The CSI LightCycle is a 60 watt pedal powered generator. Two and half hours of daily pedaling can provide four hours of reading quality light for 100 homes. Home owners can buy a locally made LED reading lamp for $1 and have their batteries charged for around $1 per month. The goal is to make the choice for electric light so affordable that home owners will not have to think twice about converting from expensive, unsafe and unhealthy cancerous kerosene. The CSI Solar Trailer is a 1.4 kW charging station with six 235 watt PV solar panels and four large 245 Amp Hour local storage batteries. The Solar Trailer has 20 parallel controllers for charging portable 12 volt home batteries. The Solar Trailer is sized to support 40 homes each with 100 watt hours of daily consumption. With IEEE funding, three pilot systems are being built for installation in Haiti. The open source 10' diameter wind turbine built by the CSI IEEE PES and EWB-USA Seattle Team provides 700 watts in 22 mph wind and costs less than $500 excluding the tower. An effort to build low cost bamboo wind turbine towers is underway. The CCS can be used to charge a range of batteries sizes and types. Open source designs are provided so that local businesses / entrepreneurs can assemble simple but highly effective LED based flashlights, desk/task lamps and ambient / room lamps for a few dollars; excluding battery costs. The CSI products are all based on an open Sustainable Energy Reference Architecture (SERA) so that there is compatibility in all interfaces and maximum commonality of components. The CSI family of products conforms to the criteria defined by Paul Polak; they are extremely affordable and highly miniaturized but infinitely scalable. It now appears that it is a reasonable goal to ensure that the entire world can have access to safe, reliable electric light by the year 2020.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"160 Pt 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128747329","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 : 2011-10-01DOI: 10.1109/APAP.2011.6180830
Sung-Jun Park, Seung-Jae Lee, Myeon-Song Cho, Taewon Kim, Sang-Tae Kim, Jin-Hwan Kim
A cascading trip of distance relay due to overload caused by another line tripping has been observed in some blackouts. Preventing such an unwanted trip of a distance relay could contribute to blackout prevention. In this paper, a new index (PVI) for evaluating vulnerability from distance protection viewpoint is proposed which indicates the risk level of a distance relay that can lead to multiple line outages due to overload. Case studies on a real system show effectiveness of the proposed index. The proposed index can be utilized to make a decision on execution of preventive actions before a blackout develops.
{"title":"A new index for evaluating protection vulnerability","authors":"Sung-Jun Park, Seung-Jae Lee, Myeon-Song Cho, Taewon Kim, Sang-Tae Kim, Jin-Hwan Kim","doi":"10.1109/APAP.2011.6180830","DOIUrl":"https://doi.org/10.1109/APAP.2011.6180830","url":null,"abstract":"A cascading trip of distance relay due to overload caused by another line tripping has been observed in some blackouts. Preventing such an unwanted trip of a distance relay could contribute to blackout prevention. In this paper, a new index (PVI) for evaluating vulnerability from distance protection viewpoint is proposed which indicates the risk level of a distance relay that can lead to multiple line outages due to overload. Case studies on a real system show effectiveness of the proposed index. The proposed index can be utilized to make a decision on execution of preventive actions before a blackout develops.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116870459","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 : 2011-07-24DOI: 10.1109/PES.2011.6039318
N. Chaudhuri, A. Yazdani
This paper proposes a new aggregation scheme for large-scale offshore wind farms. The aggregation scheme is based on direct-drive, variable-speed, wind-power units which are interfaced with a High-Voltage DC (HVDC) collector substation. Each wind-power unit employs a diode-bridge rectifier cascaded with a Sinusoidal Pulse-Width Modulated (SPWM), Voltage-Sourced Converter (VSC). The use of the diode-rectifier is expected to bring about higher efficiency, lower converter cost, and higher reliability. The offshore HVDC collector employs a three-level Neutral-Point Clamped (NPC) converter which adopts a single-pulse switching strategy. Therefore, a high voltage level is permitted while the switching losses are minimized. Moreover, the pulse width of the HVDC AC voltage is chosen such that a twelve-pulse waveform is approximated, thereby, avoiding phase-shifting transformers in the interest of lower weight and footprint. The feasibility and effectiveness of the proposed aggregation scheme and its controls are demonstrated by simulation studies in the PSCAD/EMTDC software environment.
{"title":"An aggregation scheme for offshore wind farms with VSC-based HVDC collection system","authors":"N. Chaudhuri, A. Yazdani","doi":"10.1109/PES.2011.6039318","DOIUrl":"https://doi.org/10.1109/PES.2011.6039318","url":null,"abstract":"This paper proposes a new aggregation scheme for large-scale offshore wind farms. The aggregation scheme is based on direct-drive, variable-speed, wind-power units which are interfaced with a High-Voltage DC (HVDC) collector substation. Each wind-power unit employs a diode-bridge rectifier cascaded with a Sinusoidal Pulse-Width Modulated (SPWM), Voltage-Sourced Converter (VSC). The use of the diode-rectifier is expected to bring about higher efficiency, lower converter cost, and higher reliability. The offshore HVDC collector employs a three-level Neutral-Point Clamped (NPC) converter which adopts a single-pulse switching strategy. Therefore, a high voltage level is permitted while the switching losses are minimized. Moreover, the pulse width of the HVDC AC voltage is chosen such that a twelve-pulse waveform is approximated, thereby, avoiding phase-shifting transformers in the interest of lower weight and footprint. The feasibility and effectiveness of the proposed aggregation scheme and its controls are demonstrated by simulation studies in the PSCAD/EMTDC software environment.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"150 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115597546","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 : 2011-07-24DOI: 10.1109/PES.2011.6039179
L. Lessa, A. J. Prado, M. L. Bonelli, Sérgio Kurokawa, J. Filho, L. F. Bovolato
In this article, it is represented by state variables phase a transmission line which parameters are considered frequency independently and frequency dependent. It is analyzed what is the reasonable number of π circuits and the number of blocks composed by parallel resistor and inductor in parallel for reduction of numerical oscillations. It is simulated the numerical routine with and without the effect of frequency in the longitudinal parameters. Initially, it is used state variables and π circuits representing the transmission line composing a linear system which is solved by numerical routines based on the trapezoidal rule. The effect of frequency on the line is synthesized by resistors and inductors in parallel and this representation is analyzed in details. It is described transmission lines and the frequency influence in these lines through the state variables.
{"title":"Analyses of the modifications in the π circuits for inclusion of frequency influence in transmission line representation","authors":"L. Lessa, A. J. Prado, M. L. Bonelli, Sérgio Kurokawa, J. Filho, L. F. Bovolato","doi":"10.1109/PES.2011.6039179","DOIUrl":"https://doi.org/10.1109/PES.2011.6039179","url":null,"abstract":"In this article, it is represented by state variables phase a transmission line which parameters are considered frequency independently and frequency dependent. It is analyzed what is the reasonable number of π circuits and the number of blocks composed by parallel resistor and inductor in parallel for reduction of numerical oscillations. It is simulated the numerical routine with and without the effect of frequency in the longitudinal parameters. Initially, it is used state variables and π circuits representing the transmission line composing a linear system which is solved by numerical routines based on the trapezoidal rule. The effect of frequency on the line is synthesized by resistors and inductors in parallel and this representation is analyzed in details. It is described transmission lines and the frequency influence in these lines through the state variables.","PeriodicalId":159104,"journal":{"name":"2011 IEEE Power and Energy Society General Meeting","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124432275","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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