Pub Date : 2016-05-03DOI: 10.1109/TDC.2016.7520000
M. Wagler, R. Witzmann
In this paper a sensitivity analysis for several real low voltage grids is performed. The term sensitivity hereby expresses the impact of a load flow modification in a particular node with respect to other node voltages, line currents and transformer loadings. The question of how many nodes have a sufficient effect on problem areas as well as the size of such a sensitive region is answered for low voltage grids.
{"title":"Sensitivity analysis - a key element for the operation of a flexible distribution grid","authors":"M. Wagler, R. Witzmann","doi":"10.1109/TDC.2016.7520000","DOIUrl":"https://doi.org/10.1109/TDC.2016.7520000","url":null,"abstract":"In this paper a sensitivity analysis for several real low voltage grids is performed. The term sensitivity hereby expresses the impact of a load flow modification in a particular node with respect to other node voltages, line currents and transformer loadings. The question of how many nodes have a sufficient effect on problem areas as well as the size of such a sensitive region is answered for low voltage grids.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"9 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86144593","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 : 2016-05-03DOI: 10.1109/TDC.2016.7519871
Brian P. Kelley
The electric utility industry has adjusted their thinking of substation physical security as a result of recent attacks and the issuance by NERC of CIP-014-1. As a result there is a substantial investment in upgrading existing station security and providing enhanced security at new stations. With this new design approach, there are a significant number of options, considerations and products to evaluate during the design of a physical security system. This paper will highlight key considerations that should be addressed during the design and implementation of a system to comply with CIP 014-1.
{"title":"Perimeter substation physical security design options for compliance with NERC CIP 014-1","authors":"Brian P. Kelley","doi":"10.1109/TDC.2016.7519871","DOIUrl":"https://doi.org/10.1109/TDC.2016.7519871","url":null,"abstract":"The electric utility industry has adjusted their thinking of substation physical security as a result of recent attacks and the issuance by NERC of CIP-014-1. As a result there is a substantial investment in upgrading existing station security and providing enhanced security at new stations. With this new design approach, there are a significant number of options, considerations and products to evaluate during the design of a physical security system. This paper will highlight key considerations that should be addressed during the design and implementation of a system to comply with CIP 014-1.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"1 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82956818","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 : 2016-05-03DOI: 10.1109/TDC.2016.7519964
J. Cole
To minimize the vulnerability of the electric power grid to cyberattacks the North American Electric Reliability Corporation (NERC), under the jurisdiction of the Federal Energy Regulatory Commission (FERC), has enacted and enforced cybersecurity standards that continue to evolve as technology and the nature of these threats advance. These Critical Infrastructure Protection (CIP) standards issued by NERC require utilities to meet an aggressive timeline for regulatory compliance. To supplement in-house resources, utilities rely on consultants and suppliers to meet NERC's fast approaching deadlines, such as implementing the latest NERC CIP Version 5 (V5) standards. This paper discusses major design challenges faced when upgrading substation equipment for cybersecurity enhancements and, specifically, the hardware improvements implemented for the NERC CIP V5 conversions.
{"title":"Challenges of implementing substation hardware upgrades for NERC CIP version 5 compliance to enhance cybersecurity","authors":"J. Cole","doi":"10.1109/TDC.2016.7519964","DOIUrl":"https://doi.org/10.1109/TDC.2016.7519964","url":null,"abstract":"To minimize the vulnerability of the electric power grid to cyberattacks the North American Electric Reliability Corporation (NERC), under the jurisdiction of the Federal Energy Regulatory Commission (FERC), has enacted and enforced cybersecurity standards that continue to evolve as technology and the nature of these threats advance. These Critical Infrastructure Protection (CIP) standards issued by NERC require utilities to meet an aggressive timeline for regulatory compliance. To supplement in-house resources, utilities rely on consultants and suppliers to meet NERC's fast approaching deadlines, such as implementing the latest NERC CIP Version 5 (V5) standards. This paper discusses major design challenges faced when upgrading substation equipment for cybersecurity enhancements and, specifically, the hardware improvements implemented for the NERC CIP V5 conversions.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"20 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86720216","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 : 2016-05-03DOI: 10.1109/TDC.2016.7520012
R. Pérez, A. Águila, C. Vásquez
Induction motors represent a mainstay in the industry. Its optimum performance is related to the quality of electrical supply. In this sense, when there are variations in the quality of electricity supply, the induction motor can operate in conditions that can affect its performance and shorten its life. In this paper we propose a monitoring of the voltage condition of the supply voltage in induction motors, through a classification using Support Vector Machines (SVM) to detect and classify these events. The necessary data for defining the events associated with the supply voltage are obtained with the use of ATP software, simulating these different conditions in a low voltage motor and the event classification is carried out with the use of SVM. With the use of this mathematical tool, defined areas of disturbs in the voltage will be established from measurements obtained in the simulation of each of the events, which are considered as perturbations in voltage, such as: overvoltage, undervoltage, voltage unbalance, distortion of the voltage wave, voltage sags and simultaneous combinations of some of these events. Assigning tags to each type of disturbance or disturbance combinations allows us to detect and classify the condition of energy supply in induction motors through the SVM. The results show perfect accuracy in the classification of events in the condition of voltage supply of the induction motor, which represents an alternative to the monitoring of these machines in the industry.
{"title":"Classification of the status of the voltage supply in induction motors using Support Vector Machines","authors":"R. Pérez, A. Águila, C. Vásquez","doi":"10.1109/TDC.2016.7520012","DOIUrl":"https://doi.org/10.1109/TDC.2016.7520012","url":null,"abstract":"Induction motors represent a mainstay in the industry. Its optimum performance is related to the quality of electrical supply. In this sense, when there are variations in the quality of electricity supply, the induction motor can operate in conditions that can affect its performance and shorten its life. In this paper we propose a monitoring of the voltage condition of the supply voltage in induction motors, through a classification using Support Vector Machines (SVM) to detect and classify these events. The necessary data for defining the events associated with the supply voltage are obtained with the use of ATP software, simulating these different conditions in a low voltage motor and the event classification is carried out with the use of SVM. With the use of this mathematical tool, defined areas of disturbs in the voltage will be established from measurements obtained in the simulation of each of the events, which are considered as perturbations in voltage, such as: overvoltage, undervoltage, voltage unbalance, distortion of the voltage wave, voltage sags and simultaneous combinations of some of these events. Assigning tags to each type of disturbance or disturbance combinations allows us to detect and classify the condition of energy supply in induction motors through the SVM. The results show perfect accuracy in the classification of events in the condition of voltage supply of the induction motor, which represents an alternative to the monitoring of these machines in the industry.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"6 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79694263","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 : 2016-05-03DOI: 10.1109/TDC.2016.7519854
G. Reed, B. Grainger, M. Kempker, Phillip Bierer, A. Such, R. Grubb, D. Sullivan, D. Shoup, Bryan Buterbaugh, J. Paramalingam
In this paper, the technical requirements and design of a -100 Mvar / +300 Mvar Static Var Compensator (SVC) for Indianapolis Power & Light (IPL) are discussed. The primary application and need for the SVC is driven by local generation retirement with resulting symptom of fault induced delayed voltage recovery (FIDVR) of the 138 kV transmission system. First, methodology and results of a voltage stability analysis is presented to determine the required rating of the SVC to assure acceptable system dynamic performance. Both SVC and Static Synchronous Compensator (STATCOM) Flexible AC Transmission System (FACTS) technologies were considered and evaluated for this application. Second, the design and layout of the SVC is presented along with a discussion of the control performance to adequately tune the SVC controller within desired specifications. Lastly, a brief update of the project status is provided with an expected in-service date of May 2016.
{"title":"Technical requirements and design of the Indianapolis power & light 138 kV southwest static var compensator","authors":"G. Reed, B. Grainger, M. Kempker, Phillip Bierer, A. Such, R. Grubb, D. Sullivan, D. Shoup, Bryan Buterbaugh, J. Paramalingam","doi":"10.1109/TDC.2016.7519854","DOIUrl":"https://doi.org/10.1109/TDC.2016.7519854","url":null,"abstract":"In this paper, the technical requirements and design of a -100 Mvar / +300 Mvar Static Var Compensator (SVC) for Indianapolis Power & Light (IPL) are discussed. The primary application and need for the SVC is driven by local generation retirement with resulting symptom of fault induced delayed voltage recovery (FIDVR) of the 138 kV transmission system. First, methodology and results of a voltage stability analysis is presented to determine the required rating of the SVC to assure acceptable system dynamic performance. Both SVC and Static Synchronous Compensator (STATCOM) Flexible AC Transmission System (FACTS) technologies were considered and evaluated for this application. Second, the design and layout of the SVC is presented along with a discussion of the control performance to adequately tune the SVC controller within desired specifications. Lastly, a brief update of the project status is provided with an expected in-service date of May 2016.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"41 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84660062","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 : 2016-05-03DOI: 10.1109/TDC.2016.7520048
Dan Brancaccio, M. Cassiadoro
This paper explores how synchrophasor technology can be integrated into the control room environment in manner that provides value by improving grid reliability. Specifically, this paper considers how Phasor Measurement Unit (PMU) data and synchrophasor-based application outputs can be used by System Operators and operations support staff to monitor frequency, voltage, Real and Reactive Power flows, and phase angles and detect oscillations in the Real-time Operations Horizon.
{"title":"Real world applications for synchrophasors in the control room","authors":"Dan Brancaccio, M. Cassiadoro","doi":"10.1109/TDC.2016.7520048","DOIUrl":"https://doi.org/10.1109/TDC.2016.7520048","url":null,"abstract":"This paper explores how synchrophasor technology can be integrated into the control room environment in manner that provides value by improving grid reliability. Specifically, this paper considers how Phasor Measurement Unit (PMU) data and synchrophasor-based application outputs can be used by System Operators and operations support staff to monitor frequency, voltage, Real and Reactive Power flows, and phase angles and detect oscillations in the Real-time Operations Horizon.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"73 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84756133","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 : 2016-05-03DOI: 10.1109/TDC.2016.7519886
Neeraj Nayak, Heng Chen, W. Schmus, R. Quint
Models are used widely in power system planning and operations studies, and play an important role in predicting the grid's response and preparing for contingencies. The North American Electric Reliability Corporation (NERC) has adopted standards for generator model validation requiring periodic validation of generator, exciter, governor, and stabilizer models. Using synchrophasor data provides a unique opportunity for generator owners to verify their dynamic models while the units are on-line, avoiding time-consuming and costly off-line tests. This paper describes the tool that uses PMU data at the generator terminals to validate the models without taking them offline and also presents test results. This work is built on the research done by University of Texas Arlington. A two-step process of validation and calibration is used to identify whether the model is valid and then calibrate the model parameters if needed. The validation process has been tested with simulated data and field data.
{"title":"Generator parameter validation and calibration process based on PMU data","authors":"Neeraj Nayak, Heng Chen, W. Schmus, R. Quint","doi":"10.1109/TDC.2016.7519886","DOIUrl":"https://doi.org/10.1109/TDC.2016.7519886","url":null,"abstract":"Models are used widely in power system planning and operations studies, and play an important role in predicting the grid's response and preparing for contingencies. The North American Electric Reliability Corporation (NERC) has adopted standards for generator model validation requiring periodic validation of generator, exciter, governor, and stabilizer models. Using synchrophasor data provides a unique opportunity for generator owners to verify their dynamic models while the units are on-line, avoiding time-consuming and costly off-line tests. This paper describes the tool that uses PMU data at the generator terminals to validate the models without taking them offline and also presents test results. This work is built on the research done by University of Texas Arlington. A two-step process of validation and calibration is used to identify whether the model is valid and then calibrate the model parameters if needed. The validation process has been tested with simulated data and field data.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"1 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88690216","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 : 2016-05-03DOI: 10.1109/TDC.2016.7519877
Saeed D. Manshadi, M. Khodayar
This paper proposed a hierarchical structure for the electricity market to facilitate the coordination of energy markets in distribution and transmission networks. The proposed market structure enables the integration of microgrids, which provide energy and ancillary services in distribution networks. In the proposed hierarchical structure, microgrids participate in the energy market at the distribution networks settled by the distribution network operator (DNO), and load aggregators (LAs) interact with microgrids and generation companies (GENCOs) to import/export energy to/from the distribution network electricity markets from/to the wholesale electricity market. The proposed approach addressed the synergy of energy markets by introducing dynamic game with complete information for GENCOs, microgrids, and LAs. The proposed hierarchical competition is composed of bi-level optimization problems in which the respective upper-level problems maximize the individual market participants' payoff, and the lower-level problems represent the market settlement accomplished by the DNO or the independent system operator. The bi-level problems are solved by developing sensitivity functions for market participants' payoff with respect to their bidding strategies. A case study is employed to illustrate the effectiveness of the proposed approach.
{"title":"A hierarchical electricity market structure for the smart grid paradigm","authors":"Saeed D. Manshadi, M. Khodayar","doi":"10.1109/TDC.2016.7519877","DOIUrl":"https://doi.org/10.1109/TDC.2016.7519877","url":null,"abstract":"This paper proposed a hierarchical structure for the electricity market to facilitate the coordination of energy markets in distribution and transmission networks. The proposed market structure enables the integration of microgrids, which provide energy and ancillary services in distribution networks. In the proposed hierarchical structure, microgrids participate in the energy market at the distribution networks settled by the distribution network operator (DNO), and load aggregators (LAs) interact with microgrids and generation companies (GENCOs) to import/export energy to/from the distribution network electricity markets from/to the wholesale electricity market. The proposed approach addressed the synergy of energy markets by introducing dynamic game with complete information for GENCOs, microgrids, and LAs. The proposed hierarchical competition is composed of bi-level optimization problems in which the respective upper-level problems maximize the individual market participants' payoff, and the lower-level problems represent the market settlement accomplished by the DNO or the independent system operator. The bi-level problems are solved by developing sensitivity functions for market participants' payoff with respect to their bidding strategies. A case study is employed to illustrate the effectiveness of the proposed approach.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"31 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87268471","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 : 2016-05-03DOI: 10.1109/TDC.2016.7520078
L. Zhuang, B. Johnson, Xusheng Chen, E. William
This paper develops a topology-based model for representing two-winding, shell-type, single-phase transformer inter-turn faults. The principle of duality between the electric and magnetic equivalent circuits is concisely explained. The magnetic equivalent circuit of a two-winding, shell-type, single-phase transformer is extended to the magnetic circuit of a transformer with an inter-turn fault. The model is implemented in the electromagnetic transients program using built-in component models. The model is verified against results published for a 150kVA three-phase transformer and experimental testing on 55kVA three-phase transformer constructed for internal fault testing. While the developed model is for single-phase transformers, extending it to a topology-based model for three-phase, three-legged and five-legged transformers is straight forward. This model may find usage in transformer relay protection studies.
{"title":"A topology-based model for two-winding, shell-type, single-phase transformer inter-turn faults","authors":"L. Zhuang, B. Johnson, Xusheng Chen, E. William","doi":"10.1109/TDC.2016.7520078","DOIUrl":"https://doi.org/10.1109/TDC.2016.7520078","url":null,"abstract":"This paper develops a topology-based model for representing two-winding, shell-type, single-phase transformer inter-turn faults. The principle of duality between the electric and magnetic equivalent circuits is concisely explained. The magnetic equivalent circuit of a two-winding, shell-type, single-phase transformer is extended to the magnetic circuit of a transformer with an inter-turn fault. The model is implemented in the electromagnetic transients program using built-in component models. The model is verified against results published for a 150kVA three-phase transformer and experimental testing on 55kVA three-phase transformer constructed for internal fault testing. While the developed model is for single-phase transformers, extending it to a topology-based model for three-phase, three-legged and five-legged transformers is straight forward. This model may find usage in transformer relay protection studies.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"45 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90749524","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 : 2016-05-03DOI: 10.1109/TDC.2016.7519989
D. Xu, J. Oliveira, J. Chen, R. Cameroni, E. Errico, W. Sae-Kok
This paper presents several solutions for the application of eco-efficient instrument transformers developed to help better protect our environment. Typical oil-filled and SF6 Instrument transformer products are perceived as not environment friendly and using green-house gas. An alternative solution is to replace mineral oil with BIOTEMP®, a biodegradable fluid as insulating and cooling media without significant cost increase. Meanwhile work on implementation of best practice on compact SF6 Instrument transformer design to lower its impact to environment and reduce SF6 footprint. The latest Fiber-optical Current Sensor (FOCS) integrated with Disconnect Circuit Breaker (DCB) provide not only a substation footprint reduction over 50% but also an environmental friendly design and improved operation safety for its explosion proof. Continuously developing various solutions and product will still be our focus and investment for smart grid substations to increase reliability and lower environment impact.
{"title":"Eco-efficient instrument transformer","authors":"D. Xu, J. Oliveira, J. Chen, R. Cameroni, E. Errico, W. Sae-Kok","doi":"10.1109/TDC.2016.7519989","DOIUrl":"https://doi.org/10.1109/TDC.2016.7519989","url":null,"abstract":"This paper presents several solutions for the application of eco-efficient instrument transformers developed to help better protect our environment. Typical oil-filled and SF6 Instrument transformer products are perceived as not environment friendly and using green-house gas. An alternative solution is to replace mineral oil with BIOTEMP®, a biodegradable fluid as insulating and cooling media without significant cost increase. Meanwhile work on implementation of best practice on compact SF6 Instrument transformer design to lower its impact to environment and reduce SF6 footprint. The latest Fiber-optical Current Sensor (FOCS) integrated with Disconnect Circuit Breaker (DCB) provide not only a substation footprint reduction over 50% but also an environmental friendly design and improved operation safety for its explosion proof. Continuously developing various solutions and product will still be our focus and investment for smart grid substations to increase reliability and lower environment impact.","PeriodicalId":6497,"journal":{"name":"2016 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"43 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90893345","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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