Pub Date : 2018-04-01DOI: 10.1109/TDC.2018.8440499
Wei Deng, W. Pei
Multi-terminal AC/DC interconnection is one of the important forms of future distribution network, and the uninterrupted supply operation is the foundation for system reliable operation. Concerning a medium voltage AC/DC distribution network based on multi-terminal interconnection structure, the operation modes including master-slave and peer-to-peer are analysed, and the corresponding coordinated control technology of uninterrupted supply operation under different modes is proposed. A digital/analog hybrid test platform is further built. Finally, the feasibility of the proposed coordinated control technology is tested and verified.
{"title":"Coordinated Control Technology of Uninterrupted Supply Operation for Medium Voltage Multi-Terminal AC/DC Interconnection System and its Test Platform","authors":"Wei Deng, W. Pei","doi":"10.1109/TDC.2018.8440499","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440499","url":null,"abstract":"Multi-terminal AC/DC interconnection is one of the important forms of future distribution network, and the uninterrupted supply operation is the foundation for system reliable operation. Concerning a medium voltage AC/DC distribution network based on multi-terminal interconnection structure, the operation modes including master-slave and peer-to-peer are analysed, and the corresponding coordinated control technology of uninterrupted supply operation under different modes is proposed. A digital/analog hybrid test platform is further built. Finally, the feasibility of the proposed coordinated control technology is tested and verified.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"8 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84200383","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 : 2018-04-01DOI: 10.1109/TDC.2018.8440298
Vincent Curci, Teruo Nishioka, James Grimstad
High-pressure fluid-filled (HPFF) pipe type cables make up the bulk of the underground transmission lines in North America. These cable systems started to enter commercial operation in the early 1930s and many are now beyond their design life. Although HPFF cables have provided excellent reliability, some now suffer from corrosion, leaks, and failures. HPFF cables also present system design complexity and require highly skilled personnel for operation, maintenance, and repair. Utilities in North America now face the technical and economic challenges of replacing this infrastructure to maintain reliability of supply. This paper addresses replacement using XLPE cables by re-utilizing the steel pipe and manhole system in order to reduce cost and minimize impact to traffic and stakeholders by eliminating the need to construct new lines. The paper presents constraints on pipe inside diameters, limitations on XLPE cable diameters, insulation thicknesses, cable operating stresses, and ampacity and bonding options.
{"title":"Replacement of Pipe Type Cables with Cross-Linked Polyethylene (XLPE) Cables by Utilizing the Existing Steel Pipe","authors":"Vincent Curci, Teruo Nishioka, James Grimstad","doi":"10.1109/TDC.2018.8440298","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440298","url":null,"abstract":"High-pressure fluid-filled (HPFF) pipe type cables make up the bulk of the underground transmission lines in North America. These cable systems started to enter commercial operation in the early 1930s and many are now beyond their design life. Although HPFF cables have provided excellent reliability, some now suffer from corrosion, leaks, and failures. HPFF cables also present system design complexity and require highly skilled personnel for operation, maintenance, and repair. Utilities in North America now face the technical and economic challenges of replacing this infrastructure to maintain reliability of supply. This paper addresses replacement using XLPE cables by re-utilizing the steel pipe and manhole system in order to reduce cost and minimize impact to traffic and stakeholders by eliminating the need to construct new lines. The paper presents constraints on pipe inside diameters, limitations on XLPE cable diameters, insulation thicknesses, cable operating stresses, and ampacity and bonding options.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"222 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76420333","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 : 2018-04-01DOI: 10.1109/TDC.2018.8440451
Qinqin Zhang, Hui Song, G. Sheng
Traditional pattern recognition algorithms have limitations including slow training speed and low recognition accuracy in practical engineering applications. In this paper, a new method based on Online Sequential Extreme Learning Machine (OS-ELM) is proposed. Data samples have been obtained from PD experiment of real transformer based on Ultra High Frequency (UHF) detection method. In addition, OS-ELM is compared with Extreme Learning Machine (ELM), Support Vector Machine (SVM) and Back Propagation Neural Network (BPNN) in both recognition accuracy and performance aspects. The results show that OS-ELM is not only much faster in learning speed, but also more excellent in recognition accuracy, thus more suitable for engineering applications with large volume of data samples.
{"title":"Online Sequential Extreme Learning Machine for Partial Discharge Pattern Recognition of Transformer","authors":"Qinqin Zhang, Hui Song, G. Sheng","doi":"10.1109/TDC.2018.8440451","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440451","url":null,"abstract":"Traditional pattern recognition algorithms have limitations including slow training speed and low recognition accuracy in practical engineering applications. In this paper, a new method based on Online Sequential Extreme Learning Machine (OS-ELM) is proposed. Data samples have been obtained from PD experiment of real transformer based on Ultra High Frequency (UHF) detection method. In addition, OS-ELM is compared with Extreme Learning Machine (ELM), Support Vector Machine (SVM) and Back Propagation Neural Network (BPNN) in both recognition accuracy and performance aspects. The results show that OS-ELM is not only much faster in learning speed, but also more excellent in recognition accuracy, thus more suitable for engineering applications with large volume of data samples.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"104 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88036210","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 : 2018-04-01DOI: 10.1109/TDC.2018.8440310
S. Kulkarni, Balasaheb Doiphode, Yashodhan Kulkarni
With the deregulation of the electrical power industry, utilities and service companies are operating in a changing business environment. High voltage circuit breakers are extremely important for the function of modern electric power supply systems. The need to predict the proper function of circuit breaker grew over the years as the transmission networks expanded. The maintenance of circuit breakers deserves special consideration because of their importance for routine switching and for protection of other equipments. Electric transmission system breakups and equipment destruction can occur if a circuit breaker fails to operate because of a lack of preventive maintenance. Dynamic Contact Resistance Measurement (DCRM) is known as an effective technique for assessing the condition of power circuit breakers contacts and operating mechanism. This paper gives a general review about DCRM. It discusses the practical case studies on use of DCRM for condition assessment of high voltage circuit breakers.
{"title":"An Overview of Dynamic Contact Resistance Measurement of HV Circuit Breakers","authors":"S. Kulkarni, Balasaheb Doiphode, Yashodhan Kulkarni","doi":"10.1109/TDC.2018.8440310","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440310","url":null,"abstract":"With the deregulation of the electrical power industry, utilities and service companies are operating in a changing business environment. High voltage circuit breakers are extremely important for the function of modern electric power supply systems. The need to predict the proper function of circuit breaker grew over the years as the transmission networks expanded. The maintenance of circuit breakers deserves special consideration because of their importance for routine switching and for protection of other equipments. Electric transmission system breakups and equipment destruction can occur if a circuit breaker fails to operate because of a lack of preventive maintenance. Dynamic Contact Resistance Measurement (DCRM) is known as an effective technique for assessing the condition of power circuit breakers contacts and operating mechanism. This paper gives a general review about DCRM. It discusses the practical case studies on use of DCRM for condition assessment of high voltage circuit breakers.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"21 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86302994","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 : 2018-04-01DOI: 10.1109/TDC.2018.8440345
H. Konara, U. Annakkage, C. Karawita
This paper presents a necessary stability criterion for interfacing a transient stability model to a dynamic phasor model. A voltage behind reactance type synchronous machine model, which is used in transient stability studies, is taken as the example case and it is interfaced with a dynamic phasor simulation as an external network. Dynamic phasors can be used in electromechanical-type simulations to extend the bandwidth of the simulation. In this paper a steady state stability analysis is done on the interface between the two models to determine whether the externally connected network is stable as a current injection device or a voltage injection device. The stability criterion is demonstrated using a dynamic simulation of a single machine connected to an infinite bus system.
{"title":"Stability Criterion for Interfacing a Transient Stability Model to a Dynamic Phasor Model","authors":"H. Konara, U. Annakkage, C. Karawita","doi":"10.1109/TDC.2018.8440345","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440345","url":null,"abstract":"This paper presents a necessary stability criterion for interfacing a transient stability model to a dynamic phasor model. A voltage behind reactance type synchronous machine model, which is used in transient stability studies, is taken as the example case and it is interfaced with a dynamic phasor simulation as an external network. Dynamic phasors can be used in electromechanical-type simulations to extend the bandwidth of the simulation. In this paper a steady state stability analysis is done on the interface between the two models to determine whether the externally connected network is stable as a current injection device or a voltage injection device. The stability criterion is demonstrated using a dynamic simulation of a single machine connected to an infinite bus system.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"46 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82812854","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 : 2018-04-01DOI: 10.1109/TDC.2018.8440492
Omid Abrishambaf, P. Faria, Z. Vale, J. Corchado
The daily increment of the electricity use, obligates the network operators to utilize the new concepts, such as demand response programs. These programs have a minimum capacity in the consumption reduction, therefore, the small and medium consumers cannot participate in such programs individually. Curtailment Service Provider is a new concept that can overcome this barrier, by aggregating the small and medium consumers. However, testing and validating the concepts of Curtailment Service Provider with real data in realistic scenarios is required before the massive implementation of the business models. Therefore, this paper represents a real-time simulation of a Curtailment Service Provider including 220 consumers, and 68 distributed generations. In the case studies, the reactions of two small and medium prosumers are surveyed based on different decisions of Curtailment Service Provider.
{"title":"Real-Time Simulation of a Curtailment Service Provider for Demand Response Participation","authors":"Omid Abrishambaf, P. Faria, Z. Vale, J. Corchado","doi":"10.1109/TDC.2018.8440492","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440492","url":null,"abstract":"The daily increment of the electricity use, obligates the network operators to utilize the new concepts, such as demand response programs. These programs have a minimum capacity in the consumption reduction, therefore, the small and medium consumers cannot participate in such programs individually. Curtailment Service Provider is a new concept that can overcome this barrier, by aggregating the small and medium consumers. However, testing and validating the concepts of Curtailment Service Provider with real data in realistic scenarios is required before the massive implementation of the business models. Therefore, this paper represents a real-time simulation of a Curtailment Service Provider including 220 consumers, and 68 distributed generations. In the case studies, the reactions of two small and medium prosumers are surveyed based on different decisions of Curtailment Service Provider.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"22 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83190486","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 : 2018-04-01DOI: 10.1109/TDC.2018.8440223
Niroj Gurung, S. Kamalasadan
The increasing amount of wind power generation essentially replaces the conventional synchronous generators of the power system, thereby, reducing the total inertia of the system. Reduced inertia of the system is expected to hamper the system response during contingencies. It is clear that small signal as well as transient rotor angle stability is be affected by the changing dynamics of the power grid. This paper focuses on the impact of increasing DFIG penetration and techniques to overcome the stability issues using DFIG control. The technique of using modified Rotor Side Converter (RSC) control and Grid Side Converter (GSC) control with a supplementary control loop and their capability to damp the power system oscillation have been investigated using modal analysis and non-linear time-domain analysis. The results are evaluated on Kundur two area four machine test system.
{"title":"Power System Oscillation Damping Capability of Doubly Fed Induction Generator (DFIG)","authors":"Niroj Gurung, S. Kamalasadan","doi":"10.1109/TDC.2018.8440223","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440223","url":null,"abstract":"The increasing amount of wind power generation essentially replaces the conventional synchronous generators of the power system, thereby, reducing the total inertia of the system. Reduced inertia of the system is expected to hamper the system response during contingencies. It is clear that small signal as well as transient rotor angle stability is be affected by the changing dynamics of the power grid. This paper focuses on the impact of increasing DFIG penetration and techniques to overcome the stability issues using DFIG control. The technique of using modified Rotor Side Converter (RSC) control and Grid Side Converter (GSC) control with a supplementary control loop and their capability to damp the power system oscillation have been investigated using modal analysis and non-linear time-domain analysis. The results are evaluated on Kundur two area four machine test system.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"31 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79662804","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 : 2018-04-01DOI: 10.1109/TDC.2018.8440341
B. Korobeynikov, R. Shestack, A. Ishchenko, D. Ishchenko
This paper presents a new method to implement positive, negative and zero sequence components filters based on converters with rotating magnetic field. The filters are directly connected to the traditional instrument transformers, provide galvanic isolation and generate symmetrical components signals that can be used for power system protection purpose. Filter output is the voltage proportional to symmetrical components current magnitudes. The paper provides schematic diagrams of the sequence components filters and outlines the basic theoretical principles for their design. The methodology to create various sequence components filters by simple rewiring of the secondary rotating magnetic field converter windings is also presented.
{"title":"Symmetrical Components Filters for Power System Protection Based on Converters with Rotating Magnetic Field","authors":"B. Korobeynikov, R. Shestack, A. Ishchenko, D. Ishchenko","doi":"10.1109/TDC.2018.8440341","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440341","url":null,"abstract":"This paper presents a new method to implement positive, negative and zero sequence components filters based on converters with rotating magnetic field. The filters are directly connected to the traditional instrument transformers, provide galvanic isolation and generate symmetrical components signals that can be used for power system protection purpose. Filter output is the voltage proportional to symmetrical components current magnitudes. The paper provides schematic diagrams of the sequence components filters and outlines the basic theoretical principles for their design. The methodology to create various sequence components filters by simple rewiring of the secondary rotating magnetic field converter windings is also presented.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"57 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75008457","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 : 2018-04-01DOI: 10.1109/TDC.2018.8440505
R. Doche, R. Pater, Sébastien Poirier, M. Lamarche, Y. Filion
Controlled switching has been used on Hydro-Quebec's high voltage (HV) network for about 25 years. Controlled switching has been generally proven to be quite efficient in controlling inrush currents and transient overvoltages. However, in certain circumstances, the system behaves in unexpected ways due to multiple prestrikes and dynamic voltage sharing between interconnected interrupters. This study focuses on switching capacitor banks with an ungrounded neutral. An innovative diagnostic system based on transient electromagnetic emissions analysis is used to confirm the presence of multiple prestrikes during energization of ungrounded capacitor bank. Simulations show that the third phase to close can be subjected to unexpected overvoltages which can result in a premature electrical making instant thus causing synchronization alarms and high inrush currents. This paper presents an analysis when switching a 120 kV 96 Mvar ungrounded neutral capacitor bank, using results obtained from the described system. Finally an optimized switching scheme is discussed.
{"title":"Transient Electromagnetic Emission Analysis Used to Study Controlled Switching of Ungrounded Shunt Capacitor Banks","authors":"R. Doche, R. Pater, Sébastien Poirier, M. Lamarche, Y. Filion","doi":"10.1109/TDC.2018.8440505","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440505","url":null,"abstract":"Controlled switching has been used on Hydro-Quebec's high voltage (HV) network for about 25 years. Controlled switching has been generally proven to be quite efficient in controlling inrush currents and transient overvoltages. However, in certain circumstances, the system behaves in unexpected ways due to multiple prestrikes and dynamic voltage sharing between interconnected interrupters. This study focuses on switching capacitor banks with an ungrounded neutral. An innovative diagnostic system based on transient electromagnetic emissions analysis is used to confirm the presence of multiple prestrikes during energization of ungrounded capacitor bank. Simulations show that the third phase to close can be subjected to unexpected overvoltages which can result in a premature electrical making instant thus causing synchronization alarms and high inrush currents. This paper presents an analysis when switching a 120 kV 96 Mvar ungrounded neutral capacitor bank, using results obtained from the described system. Finally an optimized switching scheme is discussed.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"16 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75681240","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 : 2018-04-01DOI: 10.1109/TDC.2018.8440537
Niannian Cai, A. Khatib, Albert Saenz, Janos Bottyan
The Silicon Valley Power (SVP) system is connected to the area transmission system via one 230 kV interconnection and five 115 kV interconnections. To reduce the active power import from the 115 kV interconnections and increase the active power import from the 230 kV interconnection (and therefore reduce the cost of active power import), SVP installed a 420 MVA, 230/230 kV phase-shifting transformer (PST) at Substation A. The PST operation at SVP should satisfy N-1 contingencies in that a loss of any important transmission line within the SVP network should not overload any other lines. This paper presents mission-priority-based active power control (P control) of a PST to achieve the optimal cost of the active power import and satisfy predetermined N-1 contingencies. A mission priority is an established control algorithm for different preset conditions. The proposed mission-priority control is tested in a closed-loop environment to demonstrate its effectiveness.
{"title":"Real-Time Automation Control of a Phase-Shifting Transformer Based on Mission Priorities","authors":"Niannian Cai, A. Khatib, Albert Saenz, Janos Bottyan","doi":"10.1109/TDC.2018.8440537","DOIUrl":"https://doi.org/10.1109/TDC.2018.8440537","url":null,"abstract":"The Silicon Valley Power (SVP) system is connected to the area transmission system via one 230 kV interconnection and five 115 kV interconnections. To reduce the active power import from the 115 kV interconnections and increase the active power import from the 230 kV interconnection (and therefore reduce the cost of active power import), SVP installed a 420 MVA, 230/230 kV phase-shifting transformer (PST) at Substation A. The PST operation at SVP should satisfy N-1 contingencies in that a loss of any important transmission line within the SVP network should not overload any other lines. This paper presents mission-priority-based active power control (P control) of a PST to achieve the optimal cost of the active power import and satisfy predetermined N-1 contingencies. A mission priority is an established control algorithm for different preset conditions. The proposed mission-priority control is tested in a closed-loop environment to demonstrate its effectiveness.","PeriodicalId":6568,"journal":{"name":"2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D)","volume":"89 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74527827","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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