Pub Date : 2014-07-27DOI: 10.1109/PESGM.2014.6938775
S. P. Teeuwsen
This paper presents a study initiated by the IEEE Working Group 15.05.02 “Dynamic Performance and Modeling of HVDC & FACTS”. The Working Group is concerned with the dynamic performance of HVDC and FACTS devices under different aspects in the time domain and in the frequency domain. Converter and controller modeling, electro-mechanic and electro-magnetic phenomena, and dynamic interaction with the power system is studied carefully. Study results are discussed and recommendations for modeling drawn and published. This paper presents utilization methods for a STATCOM device, which is equipped with a power oscillation damping controller with optimized parameters. Different input signals for the damping controller are studied and compared in the time domain and in the frequency domain. Furthermore, aspects on the dynamic performance and the optimal location in large power systems for damping of inter-area oscillations are studied and discussed.
{"title":"POD utilization methods for STATCOMs","authors":"S. P. Teeuwsen","doi":"10.1109/PESGM.2014.6938775","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6938775","url":null,"abstract":"This paper presents a study initiated by the IEEE Working Group 15.05.02 “Dynamic Performance and Modeling of HVDC & FACTS”. The Working Group is concerned with the dynamic performance of HVDC and FACTS devices under different aspects in the time domain and in the frequency domain. Converter and controller modeling, electro-mechanic and electro-magnetic phenomena, and dynamic interaction with the power system is studied carefully. Study results are discussed and recommendations for modeling drawn and published. This paper presents utilization methods for a STATCOM device, which is equipped with a power oscillation damping controller with optimized parameters. Different input signals for the damping controller are studied and compared in the time domain and in the frequency domain. Furthermore, aspects on the dynamic performance and the optimal location in large power systems for damping of inter-area oscillations are studied and discussed.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"194 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132349216","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 : 2014-07-27DOI: 10.1109/PESGM.2014.6939218
Yi Yang, K. Mclaughlin, S. Sezer, Yuba Yuan, W. Huang
Cyber threats in Supervisory Control and Data Acquisition (SCADA) systems have the potential to render physical damage and jeopardize power system operation, safety and stability. SCADA systems were originally designed with little consideration of escalating cyber threats and hence the problem of how to develop robust intrusion detection technologies to tailor the requirements of SCADA is an emerging topic and a big challenge. This paper proposes a stateful Intrusion Detection System (IDS) using a Deep Packet Inspection (DPI) method to improve the cyber-security of SCADA systems using the IEC 60870-5-104 protocol which is tailored for basic telecontrol communications. The proposed stateful protocol analysis approach is presented that is designed specifically for the IEC 60870-5-104 protocol. Finally, the novel intrusion detection approach are implemented and validated.
{"title":"Stateful intrusion detection for IEC 60870-5-104 SCADA security","authors":"Yi Yang, K. Mclaughlin, S. Sezer, Yuba Yuan, W. Huang","doi":"10.1109/PESGM.2014.6939218","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939218","url":null,"abstract":"Cyber threats in Supervisory Control and Data Acquisition (SCADA) systems have the potential to render physical damage and jeopardize power system operation, safety and stability. SCADA systems were originally designed with little consideration of escalating cyber threats and hence the problem of how to develop robust intrusion detection technologies to tailor the requirements of SCADA is an emerging topic and a big challenge. This paper proposes a stateful Intrusion Detection System (IDS) using a Deep Packet Inspection (DPI) method to improve the cyber-security of SCADA systems using the IEC 60870-5-104 protocol which is tailored for basic telecontrol communications. The proposed stateful protocol analysis approach is presented that is designed specifically for the IEC 60870-5-104 protocol. Finally, the novel intrusion detection approach are implemented and validated.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130186200","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 : 2014-07-27DOI: 10.1109/PESGM.2014.6939792
S. Siddique, R. Povinelli
Domain knowledge is an essential factor for forecasting energy demand. This paper introduces a method that incorporates machine learning techniques to learn domain knowledge by transforming the input features. Our approach divides the inputs into subsets and then searches for the best machine learning technique for transforming each subset of inputs. Preprocessing of the inputs is not required in our approach because the machine learning techniques appropriately transform the inputs. Hence, this technique is capable of learning where nonlinear transformations of the inputs are needed. We show that the learned data transformations correspond to energy forecasting domain knowledge. Transformed subsets of the inputs are combined using ensemble regression, and the final forecasted value is obtained. Our approach is tested with natural gas and electricity demand signals. Experimental results show how this method can learn domain knowledge, which yields improved forecasts.
{"title":"Learning energy demand domain knowledge via feature transformation","authors":"S. Siddique, R. Povinelli","doi":"10.1109/PESGM.2014.6939792","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939792","url":null,"abstract":"Domain knowledge is an essential factor for forecasting energy demand. This paper introduces a method that incorporates machine learning techniques to learn domain knowledge by transforming the input features. Our approach divides the inputs into subsets and then searches for the best machine learning technique for transforming each subset of inputs. Preprocessing of the inputs is not required in our approach because the machine learning techniques appropriately transform the inputs. Hence, this technique is capable of learning where nonlinear transformations of the inputs are needed. We show that the learned data transformations correspond to energy forecasting domain knowledge. Transformed subsets of the inputs are combined using ensemble regression, and the final forecasted value is obtained. Our approach is tested with natural gas and electricity demand signals. Experimental results show how this method can learn domain knowledge, which yields improved forecasts.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130239225","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 : 2014-07-27DOI: 10.1109/PESGM.2014.6938819
J. Dickert, Gunjan Seth, P. Schegner
The progression of embedded generation in distribution networks combined with an expanding use of electricity for mobility, heating and air conditioning leads to an increased loading of the distribution networks. These incoming challenges and their consequences make us reflect whether it is reasonable to retain the present design concepts and paradigms. The paper analyzes the required capabilities of the future low voltage distribution networks, expressing them in terms of demand and coincidence of the demand. Based on these requirements, various design concept scenarios are developed and tested on an exemplary network topology. Rather than adjusting the cross section of the cables or adding substations to the network (to reduce the distance between substations and delivery points), the nominal voltage and the voltage tolerance range are varied. This basic investigation forms the evolution paths for low voltage distribution systems and provides a platform for further discussion. A change in design paradigms is laborious, but a well prepared transition of the systems' design concepts has the potential to be a more economical solution than the unquestioned use of aged design concepts.
{"title":"Comparison of design concepts for AC low voltage distribution networks","authors":"J. Dickert, Gunjan Seth, P. Schegner","doi":"10.1109/PESGM.2014.6938819","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6938819","url":null,"abstract":"The progression of embedded generation in distribution networks combined with an expanding use of electricity for mobility, heating and air conditioning leads to an increased loading of the distribution networks. These incoming challenges and their consequences make us reflect whether it is reasonable to retain the present design concepts and paradigms. The paper analyzes the required capabilities of the future low voltage distribution networks, expressing them in terms of demand and coincidence of the demand. Based on these requirements, various design concept scenarios are developed and tested on an exemplary network topology. Rather than adjusting the cross section of the cables or adding substations to the network (to reduce the distance between substations and delivery points), the nominal voltage and the voltage tolerance range are varied. This basic investigation forms the evolution paths for low voltage distribution systems and provides a platform for further discussion. A change in design paradigms is laborious, but a well prepared transition of the systems' design concepts has the potential to be a more economical solution than the unquestioned use of aged design concepts.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130439436","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 : 2014-07-27DOI: 10.1109/PESGM.2014.6938823
X. Zhang, Z. Y. Xu, M. J. Iqbal, Q. Yang
Wind farm automatic generation control (WFAGC) dispatch strategy is important for large-scale grid connected wind farms. This paper addresses challenges in WFAGC. Specifically, it proposes a WFAGC dispatch strategy. This strategy consists of wind farm dispatch center, AGC substation and performance evaluation station. Active power realtime control and wind power allocation policy are also discussed. The proposed strategy has been tested using computer simulation on a large-scale wind farm built in China. The simulation shows that the proposed strategy is flexible and convenient for wind power control.
{"title":"Dispatch strategy of large-scale wind farm automatic generation control system","authors":"X. Zhang, Z. Y. Xu, M. J. Iqbal, Q. Yang","doi":"10.1109/PESGM.2014.6938823","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6938823","url":null,"abstract":"Wind farm automatic generation control (WFAGC) dispatch strategy is important for large-scale grid connected wind farms. This paper addresses challenges in WFAGC. Specifically, it proposes a WFAGC dispatch strategy. This strategy consists of wind farm dispatch center, AGC substation and performance evaluation station. Active power realtime control and wind power allocation policy are also discussed. The proposed strategy has been tested using computer simulation on a large-scale wind farm built in China. The simulation shows that the proposed strategy is flexible and convenient for wind power control.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134219895","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 : 2014-07-27DOI: 10.1109/PESGM.2014.6939282
D. Nikolić, M. Negnevitsky, M. de Groot, S. Gamble, J. Forbes, M. Ross
Isolated power systems (IPSs) up to 20MW capacity are often based on diesel generators. Due to the high cost of diesel fuel supply, as well as environmental concerns, IPSs should ideally include a large proportion of renewable energy generation. We report on the implementation of a simple, finegrained and fast demand response (DR) technology to enable high wind penetration in an IPS. This solution is based on centralized two-way communication and control of residential and commercial loads. DR can be dispatched and confirmed within 1 second. The technology has been installed and successfully tested in an IPS on an island in Australia.
{"title":"Fast demand response as an enabling technology for high renewable energy penetration in isolated power systems","authors":"D. Nikolić, M. Negnevitsky, M. de Groot, S. Gamble, J. Forbes, M. Ross","doi":"10.1109/PESGM.2014.6939282","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939282","url":null,"abstract":"Isolated power systems (IPSs) up to 20MW capacity are often based on diesel generators. Due to the high cost of diesel fuel supply, as well as environmental concerns, IPSs should ideally include a large proportion of renewable energy generation. We report on the implementation of a simple, finegrained and fast demand response (DR) technology to enable high wind penetration in an IPS. This solution is based on centralized two-way communication and control of residential and commercial loads. DR can be dispatched and confirmed within 1 second. The technology has been installed and successfully tested in an IPS on an island in Australia.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"183 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134244379","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 : 2014-07-27DOI: 10.1109/PESGM.2014.6938997
Aric James Litchy, M. H. Nehrir, Robert C. Maher, Ronald W. Larsen, H. Nehrir, Robert Gunderson, Hongwei Gao, Mohammad Moghimi, Jon Wilson, Nick Havens, Stasha Patrick, Chris Colson, Colin Young, Kevin Marchese, Andrew Cifala
While minimizing cost has always been a primary objective in energy management, because of increasing concerns over emissions, minimization of this objective has been brought to the forefront of energy management as well. Minimization of cost and emission are two conflicting objectives. Moreover, the optimization problem becomes more complex with the addition of renewable technologies that have varying power generation energy storage. This paper presents a multi-objective, multi-constraint energy management optimization problem for an islanded microgrid solved in real time using a modified Multi-objective Particle Swarm Optimization (MOPSO) algorithm. Simulation results show the benefits of real-time optimization and the freedom of choice users make to meet their energy demands. Furthermore, the simulation results from the MOPSO-based algorithm are compared with those from the Multi-objective Genetic Algorithm (MOGA)-based optimization package available in the Matlab optimization toolbox. The results show that the proposed MOPSO-based algorithm used for a 24-hour period energy management simulation performs much faster than the MOGA-based optimization package.
{"title":"Real-time energy management of an islanded microgrid using multi-objective Particle Swarm Optimization","authors":"Aric James Litchy, M. H. Nehrir, Robert C. Maher, Ronald W. Larsen, H. Nehrir, Robert Gunderson, Hongwei Gao, Mohammad Moghimi, Jon Wilson, Nick Havens, Stasha Patrick, Chris Colson, Colin Young, Kevin Marchese, Andrew Cifala","doi":"10.1109/PESGM.2014.6938997","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6938997","url":null,"abstract":"While minimizing cost has always been a primary objective in energy management, because of increasing concerns over emissions, minimization of this objective has been brought to the forefront of energy management as well. Minimization of cost and emission are two conflicting objectives. Moreover, the optimization problem becomes more complex with the addition of renewable technologies that have varying power generation energy storage. This paper presents a multi-objective, multi-constraint energy management optimization problem for an islanded microgrid solved in real time using a modified Multi-objective Particle Swarm Optimization (MOPSO) algorithm. Simulation results show the benefits of real-time optimization and the freedom of choice users make to meet their energy demands. Furthermore, the simulation results from the MOPSO-based algorithm are compared with those from the Multi-objective Genetic Algorithm (MOGA)-based optimization package available in the Matlab optimization toolbox. The results show that the proposed MOPSO-based algorithm used for a 24-hour period energy management simulation performs much faster than the MOGA-based optimization package.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134302276","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 : 2014-07-27DOI: 10.1109/PESGM.2014.6939030
S. Lefebvre, J. Prévost, L. Lenoir
State estimation problems for distribution networks differ from classical state estimation ones. The limited number of measurements makes the problem mathematically underdetermined without the addition of pseudo-measurements. Issues associated with the connection of distributed resources and control efficiency have led to the requirement for greater observability of power networks, but this has to be balanced against the cost of additional measurement and telemetry, including possible redundancy. The impact of estimating accurately the system state is examined in the context of transversal voltage control.
{"title":"Distribution state estimation: A necessary requirement for the smart grid","authors":"S. Lefebvre, J. Prévost, L. Lenoir","doi":"10.1109/PESGM.2014.6939030","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939030","url":null,"abstract":"State estimation problems for distribution networks differ from classical state estimation ones. The limited number of measurements makes the problem mathematically underdetermined without the addition of pseudo-measurements. Issues associated with the connection of distributed resources and control efficiency have led to the requirement for greater observability of power networks, but this has to be balanced against the cost of additional measurement and telemetry, including possible redundancy. The impact of estimating accurately the system state is examined in the context of transversal voltage control.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131888737","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 : 2014-07-27DOI: 10.1109/PESGM.2014.6939797
Hader Azzini, R. Torquato, L. D. da Silva
This paper proposes two novel algorithms to detect appliance switch-ON/OFF events, which is the first key step of a Nonintrusive Load Monitoring (NILM) software. The Window with Margins method uses the left and right margins of a window running over the house power consumption curve to locate power steps, while the Shifted Sample method relies on the derivative of the power consumption curve to identify power steps. The former may achieve higher event detection rates, while the latter presents very low complexity and requires a reduced computational effort. Extensive sensitivity studies were performed with the parameters of each method, and obtained results have shown the importance of an adequate parameter setting, as successful event identification rates may be increased up to 95%. The applicability and effectiveness of such algorithms have been verified using field measurement data.
{"title":"Event detection methods for nonintrusive load monitoring","authors":"Hader Azzini, R. Torquato, L. D. da Silva","doi":"10.1109/PESGM.2014.6939797","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939797","url":null,"abstract":"This paper proposes two novel algorithms to detect appliance switch-ON/OFF events, which is the first key step of a Nonintrusive Load Monitoring (NILM) software. The Window with Margins method uses the left and right margins of a window running over the house power consumption curve to locate power steps, while the Shifted Sample method relies on the derivative of the power consumption curve to identify power steps. The former may achieve higher event detection rates, while the latter presents very low complexity and requires a reduced computational effort. Extensive sensitivity studies were performed with the parameters of each method, and obtained results have shown the importance of an adequate parameter setting, as successful event identification rates may be increased up to 95%. The applicability and effectiveness of such algorithms have been verified using field measurement data.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"51 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130695915","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 : 2014-07-27DOI: 10.1109/PESGM.2014.6939515
Xingpeng Li, Guangchao Geng, Q. Jiang
A novel hierarchical energy management strategy for grid-connected microgird is proposed in this paper. The proposed concept follows the idea of multiple time-scale coordination and consists of day-ahead layer, adjustment layer, and real-time layer. The day-ahead layer is based on look-ahead multi-step optimization techniques and the predicted availability of renewable energy sources. Future operational states of the controllable units in the microgrid could be determined ahead of time. The adjustment layer adjusts power output of online units by using the data at the dispatch time. Then, real-time layer is utilized to maintain the exchange power between the external macrogrid and the microgrid constant. In addition, energy storage plays a critical role in three dispatch and control layers. A typical microgrid system is simulated to demonstrate the performance and effectiveness of the proposed hierarchical energy management strategy.
{"title":"A hierarchical energy management strategy for grid-connected microgrid","authors":"Xingpeng Li, Guangchao Geng, Q. Jiang","doi":"10.1109/PESGM.2014.6939515","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939515","url":null,"abstract":"A novel hierarchical energy management strategy for grid-connected microgird is proposed in this paper. The proposed concept follows the idea of multiple time-scale coordination and consists of day-ahead layer, adjustment layer, and real-time layer. The day-ahead layer is based on look-ahead multi-step optimization techniques and the predicted availability of renewable energy sources. Future operational states of the controllable units in the microgrid could be determined ahead of time. The adjustment layer adjusts power output of online units by using the data at the dispatch time. Then, real-time layer is utilized to maintain the exchange power between the external macrogrid and the microgrid constant. In addition, energy storage plays a critical role in three dispatch and control layers. A typical microgrid system is simulated to demonstrate the performance and effectiveness of the proposed hierarchical energy management strategy.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132953385","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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