Pub Date : 2014-07-27DOI: 10.1109/PESGM.2014.6939304
Parul Mathuria, R. Bhakar
Fossil fuel gencos are subject to influence of multiple uncertain but interactive energy and emission markets. It procures production resources from fuel and emission market and sells its generation through multiple contracts in electricity market. With increasing volatility and unpredictability in energy markets, a genco needs to make prudent decision to manage its trading in all involved markets, to guarantee minimum profit. Considering the existing market uncertainties and associated information gap, this paper proposes a robust decision making approach for gencos trading portfolio selection in all three involved markets, based on Information Gap Decision Theory (IGDT). Results from a realistic case study provides a range of decisions for a risk averse genco, appropriate to its nature, and based on the trade-off existing between robustness and targeted profit.
{"title":"IGDT based Genco's trading decision making in multimarket environment","authors":"Parul Mathuria, R. Bhakar","doi":"10.1109/PESGM.2014.6939304","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939304","url":null,"abstract":"Fossil fuel gencos are subject to influence of multiple uncertain but interactive energy and emission markets. It procures production resources from fuel and emission market and sells its generation through multiple contracts in electricity market. With increasing volatility and unpredictability in energy markets, a genco needs to make prudent decision to manage its trading in all involved markets, to guarantee minimum profit. Considering the existing market uncertainties and associated information gap, this paper proposes a robust decision making approach for gencos trading portfolio selection in all three involved markets, based on Information Gap Decision Theory (IGDT). Results from a realistic case study provides a range of decisions for a risk averse genco, appropriate to its nature, and based on the trade-off existing between robustness and targeted profit.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"43 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":"128046674","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.2014.6939562
Desong Bian, M. Kuzlu, M. Pipattanasomporn, Saifur Rahman
With the introduction of the smart grid, Advanced Metering Infrastructure (AMI) has become an important element in the modern power system. The successful implementation of AMI is dependent on its communication scheme that provides reliable two-way communications. The objective of this paper is to provide a comprehensive review of possible AMI communication network infrastructures based on real-world smart grid projects, and analyze their advantages and disadvantages. The most promising AMI communication scheme is then recommended, which is a hybrid version of WiMAX and fiber optic. The recommended solution is simulated in OPNET using the case study of a small-scale AMI network. Network performance is then evaluated based on smart metering system requirements specified in IEEE Std 2030-2011.
{"title":"Analysis of communication schemes for Advanced Metering Infrastructure (AMI)","authors":"Desong Bian, M. Kuzlu, M. Pipattanasomporn, Saifur Rahman","doi":"10.1109/PESGM.2014.6939562","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939562","url":null,"abstract":"With the introduction of the smart grid, Advanced Metering Infrastructure (AMI) has become an important element in the modern power system. The successful implementation of AMI is dependent on its communication scheme that provides reliable two-way communications. The objective of this paper is to provide a comprehensive review of possible AMI communication network infrastructures based on real-world smart grid projects, and analyze their advantages and disadvantages. The most promising AMI communication scheme is then recommended, which is a hybrid version of WiMAX and fiber optic. The recommended solution is simulated in OPNET using the case study of a small-scale AMI network. Network performance is then evaluated based on smart metering system requirements specified in IEEE Std 2030-2011.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"2018 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":"128046906","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.2014.6939110
B. Gustavsen, Álvaro Portillo
The standard lightning impulse voltage wave used in transformer factory testing does not properly cover all the overvoltage stresses that a transformer can experience while in service. To properly asses the internal overvoltages that can occur in practice, we propose to interface the manufacturer's white-box transformer model with EMTP-type simulation tools using a black-box modeling approach. From the white-box model we compute in the frequency domain data for the blackbox model which are fitted with rational functions, including voltage transfer functions from external terminals to internal nodes. The resulting black-box model is easily interfaced with EMTP-type circuit solvers via a Norton equivalent and recursive convolution. Application to the so-called fictitious transformer used by CIGRE A2/C4.39 demonstrates that ground fault initiation on a connected cable can generate internal overvoltages that exceed those of the lightning impulse test.
{"title":"A black-box approach to interfacing white-box transformer models with electromagnetic transients programs","authors":"B. Gustavsen, Álvaro Portillo","doi":"10.1109/PESGM.2014.6939110","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939110","url":null,"abstract":"The standard lightning impulse voltage wave used in transformer factory testing does not properly cover all the overvoltage stresses that a transformer can experience while in service. To properly asses the internal overvoltages that can occur in practice, we propose to interface the manufacturer's white-box transformer model with EMTP-type simulation tools using a black-box modeling approach. From the white-box model we compute in the frequency domain data for the blackbox model which are fitted with rational functions, including voltage transfer functions from external terminals to internal nodes. The resulting black-box model is easily interfaced with EMTP-type circuit solvers via a Norton equivalent and recursive convolution. Application to the so-called fictitious transformer used by CIGRE A2/C4.39 demonstrates that ground fault initiation on a connected cable can generate internal overvoltages that exceed those of the lightning impulse test.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"156 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":"128104080","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.2014.6939272
X. Liu, D. Laverty, R. Best
This paper proposes a probabilistic principal component analysis (PCA) approach applied to islanding detection study based on wide area PMU data. The increasing probability of uncontrolled islanding operation, according to many power system operators, is one of the biggest concerns with a large penetration of distributed renewable generation. The traditional islanding detection methods, such as RoCoF and vector shift, are however extremely sensitive and may result in many unwanted trips. The proposed probabilistic PCA aims to improve islanding detection accuracy and reduce the risk of unwanted tripping based on PMU measurements, while addressing a practical issue on missing data. The reliability and accuracy of the proposed probabilistic PCA approach are demonstrated using real data recorded in the UK power system by the OpenPMU project. The results show that the proposed methods can detect islanding accurately, without being falsely triggered by generation trips, even in the presence of missing values.
{"title":"Islanding detection based on probabilistic PCA with missing values in PMU data","authors":"X. Liu, D. Laverty, R. Best","doi":"10.1109/PESGM.2014.6939272","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939272","url":null,"abstract":"This paper proposes a probabilistic principal component analysis (PCA) approach applied to islanding detection study based on wide area PMU data. The increasing probability of uncontrolled islanding operation, according to many power system operators, is one of the biggest concerns with a large penetration of distributed renewable generation. The traditional islanding detection methods, such as RoCoF and vector shift, are however extremely sensitive and may result in many unwanted trips. The proposed probabilistic PCA aims to improve islanding detection accuracy and reduce the risk of unwanted tripping based on PMU measurements, while addressing a practical issue on missing data. The reliability and accuracy of the proposed probabilistic PCA approach are demonstrated using real data recorded in the UK power system by the OpenPMU project. The results show that the proposed methods can detect islanding accurately, without being falsely triggered by generation trips, even in the presence of missing values.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"159 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":"128143300","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.2014.6939857
P. Irminger, M. Starke, A. Dimitrovski, M. Young, D. Rizy, J. Stovall, P. Overholt
Power system equipment manufacturers and researchers continue to experiment with novel overhead electric conductor designs that support better conductor performance and address congestion issues. To address the technology gap in testing these novel designs, Oak Ridge National Laboratory constructed the Powerline Conductor Accelerated Testing (PCAT) facility to evaluate the performance of novel overhead conductors in an accelerated fashion in a field environment. Additionally, PCAT has the capability to test advanced sensors and measurement methods for accessing overhead conductor performance and condition. Equipped with extensive measurement and monitoring devices, PCAT provides a platform to improve/validate conductor computer models and assess the performance of novel conductors. The PCAT facility and its testing capabilities are described in this paper.
{"title":"A testing platform for validation of overhead conductor aging models and understanding thermal limits","authors":"P. Irminger, M. Starke, A. Dimitrovski, M. Young, D. Rizy, J. Stovall, P. Overholt","doi":"10.1109/PESGM.2014.6939857","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939857","url":null,"abstract":"Power system equipment manufacturers and researchers continue to experiment with novel overhead electric conductor designs that support better conductor performance and address congestion issues. To address the technology gap in testing these novel designs, Oak Ridge National Laboratory constructed the Powerline Conductor Accelerated Testing (PCAT) facility to evaluate the performance of novel overhead conductors in an accelerated fashion in a field environment. Additionally, PCAT has the capability to test advanced sensors and measurement methods for accessing overhead conductor performance and condition. Equipped with extensive measurement and monitoring devices, PCAT provides a platform to improve/validate conductor computer models and assess the performance of novel conductors. The PCAT facility and its testing capabilities are described in this paper.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"55 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":"127917310","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.2014.6938936
Joshua A. Taylor
There has been recent discussion as to whether energy storage should be an active market participant that buys and sells power at wholesale prices or a passive entity like a transmission line. In the latter case, new market mechanisms must be developed to integrate storage into electricity markets. In this paper, we define financial rights for energy storage. As with financial transmission rights, risk-averse market participants can acquire the storage rights to hedge against nodal price volatility resulting from storage congestion. We demonstrate that the rights specify how a system operator can redistribute budget surpluses resulting from storage congestion, as flowgate rights do for transmission congestion. We also derive a tracing rule that enables power flows through transmission lines and storage to be decomposed into present and past nodal contributions.
{"title":"Financial rights and tracing for energy storage","authors":"Joshua A. Taylor","doi":"10.1109/PESGM.2014.6938936","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6938936","url":null,"abstract":"There has been recent discussion as to whether energy storage should be an active market participant that buys and sells power at wholesale prices or a passive entity like a transmission line. In the latter case, new market mechanisms must be developed to integrate storage into electricity markets. In this paper, we define financial rights for energy storage. As with financial transmission rights, risk-averse market participants can acquire the storage rights to hedge against nodal price volatility resulting from storage congestion. We demonstrate that the rights specify how a system operator can redistribute budget surpluses resulting from storage congestion, as flowgate rights do for transmission congestion. We also derive a tracing rule that enables power flows through transmission lines and storage to be decomposed into present and past nodal contributions.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"261 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":"115791444","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.2014.6939874
James Hurtt, D. Jhirad, Jessica J. Lewis
There is a strong correlation between access to electricity and quality of life. Approximately 1.4 billion people in the world currently lack access to electricity. Furthermore, 85% of the people without access to electricity live in rural areas. The cost of installing electrical infrastructure to these remote communities is often unrealistic. Microgrids offer another approach for electrification of some of the worlds most remote rural areas. Standalone microgrids can be used in an economically favorable, environmentally benign, and sustainable fashion to meet the needs of these rural communities. This paper provides an overview of the work being performed by the SPEED consortium to develop rural microgrids in India and the modeling effort the team put together to capture the renewable energy resources available in those areas. While SPEED works to develop a variety of renewable based microgrids, only the solar based model is covered in this paper. The model was developed in MATLAB using field data from India's Ministry of New and Renewable Energy and team partners.
{"title":"Solar resource model for rural microgrids in India","authors":"James Hurtt, D. Jhirad, Jessica J. Lewis","doi":"10.1109/PESGM.2014.6939874","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939874","url":null,"abstract":"There is a strong correlation between access to electricity and quality of life. Approximately 1.4 billion people in the world currently lack access to electricity. Furthermore, 85% of the people without access to electricity live in rural areas. The cost of installing electrical infrastructure to these remote communities is often unrealistic. Microgrids offer another approach for electrification of some of the worlds most remote rural areas. Standalone microgrids can be used in an economically favorable, environmentally benign, and sustainable fashion to meet the needs of these rural communities. This paper provides an overview of the work being performed by the SPEED consortium to develop rural microgrids in India and the modeling effort the team put together to capture the renewable energy resources available in those areas. While SPEED works to develop a variety of renewable based microgrids, only the solar based model is covered in this paper. The model was developed in MATLAB using field data from India's Ministry of New and Renewable Energy and team partners.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"255 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":"115863241","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.2014.6938932
Peng Li, Zeyuan Zhou, R. Shi
This paper proposes improved bat algorithm along with point estimate method to optimize the operation of microgrid. The objective function and constraints related to the operation of microgrid are formulated and mathematical model is established. The point estimate method is used to deal with the uncertainty in load demand and output power of solar and wind units. Numerical examples analyze the performance of proposed method on solving the optimal problem. Besides, the probability distribution of total operating cost, and the effects of random variables on operating cost are presented. The proposed model and method are validated with the numerical results.
{"title":"Probabilistic optimal operation management of microgrid using point estimate method and improved bat algorithm","authors":"Peng Li, Zeyuan Zhou, R. Shi","doi":"10.1109/PESGM.2014.6938932","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6938932","url":null,"abstract":"This paper proposes improved bat algorithm along with point estimate method to optimize the operation of microgrid. The objective function and constraints related to the operation of microgrid are formulated and mathematical model is established. The point estimate method is used to deal with the uncertainty in load demand and output power of solar and wind units. Numerical examples analyze the performance of proposed method on solving the optimal problem. Besides, the probability distribution of total operating cost, and the effects of random variables on operating cost are presented. The proposed model and method are validated with the numerical results.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"29 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":"131361764","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.2014.6938961
Yun Li, P. Crossley
The impact of electric vehicles (EVs) on the voltages seen on a low voltage (LV) feeder are investigated in this paper. The Monte Carlo method was used to understand the impact of diversity of demand on LV feeders and especially the effect of uncontrolled human behavior. A statistical model of an EV was established to generate random high-resolution EV charging demand profiles. Moreover, both the balanced and unbalanced scenarios, with different EV charging locations, were investigated in a simulation study. The results were analyzed and used to illustrate how time of use tariffs can alleviate voltage drops and imbalance.
{"title":"Impact of electric vehicles on LV feeder voltages","authors":"Yun Li, P. Crossley","doi":"10.1109/PESGM.2014.6938961","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6938961","url":null,"abstract":"The impact of electric vehicles (EVs) on the voltages seen on a low voltage (LV) feeder are investigated in this paper. The Monte Carlo method was used to understand the impact of diversity of demand on LV feeders and especially the effect of uncontrolled human behavior. A statistical model of an EV was established to generate random high-resolution EV charging demand profiles. Moreover, both the balanced and unbalanced scenarios, with different EV charging locations, were investigated in a simulation study. The results were analyzed and used to illustrate how time of use tariffs can alleviate voltage drops and imbalance.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"19 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":"132053501","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.2014.6939397
Yichi Zhang, Yingmeng Xiang, Lingfeng Wang
As information and communication networks are highly interconnected with the power grid, cyber security of the supervisory control and data acquisition (SCADA) system has become a critical issue in the power system. By intruding into the SCADA system via the remote access points, the attackers are able to eavesdrop critical data and reconfigure devices to trip the system breakers. The cyber attacks are able to impact the reliability of the power system through the SCADA system. In this paper, six cyber attack scenarios in the SCADA system are considered. A Bayesian attack graph model is used to evaluate the probabilities of successful cyber attacks on the SCADA system, which will result in breaker trips. A forced outage rate (FOR) model is proposed considering the frequencies of successful attacks on the generators and transmission lines. With increased FOR values resulted from the cyber attacks, the loss of load probabilities (LOLP) in reliability test system 79 (RTS79) are estimated. The results of the simulations demonstrate that the power system becomes less reliable as the frequency of successful attacks increases.
随着信息通信网络与电网的高度互联，SCADA (supervisory control and data acquisition)系统的网络安全已成为电力系统中的关键问题。通过远程访问点侵入SCADA系统，攻击者能够窃听关键数据并重新配置设备以触发系统断路器。网络攻击可以通过SCADA系统影响电力系统的可靠性。本文考虑了SCADA系统中的六种网络攻击场景。利用贝叶斯攻击图模型评估了SCADA系统网络攻击成功导致断路器脱扣的概率。考虑发电机和输电线路被成功攻击的频率，提出了一种强制停电率模型。根据网络攻击导致的FOR值的增加，对可靠性测试系统(RTS79)的负载损失概率(LOLP)进行了估计。仿真结果表明，随着攻击成功率的增加，电力系统的可靠性降低。
{"title":"Reliability analysis of power grids with cyber vulnerability in SCADA system","authors":"Yichi Zhang, Yingmeng Xiang, Lingfeng Wang","doi":"10.1109/PESGM.2014.6939397","DOIUrl":"https://doi.org/10.1109/PESGM.2014.6939397","url":null,"abstract":"As information and communication networks are highly interconnected with the power grid, cyber security of the supervisory control and data acquisition (SCADA) system has become a critical issue in the power system. By intruding into the SCADA system via the remote access points, the attackers are able to eavesdrop critical data and reconfigure devices to trip the system breakers. The cyber attacks are able to impact the reliability of the power system through the SCADA system. In this paper, six cyber attack scenarios in the SCADA system are considered. A Bayesian attack graph model is used to evaluate the probabilities of successful cyber attacks on the SCADA system, which will result in breaker trips. A forced outage rate (FOR) model is proposed considering the frequencies of successful attacks on the generators and transmission lines. With increased FOR values resulted from the cyber attacks, the loss of load probabilities (LOLP) in reliability test system 79 (RTS79) are estimated. The results of the simulations demonstrate that the power system becomes less reliable as the frequency of successful attacks increases.","PeriodicalId":149134,"journal":{"name":"2014 IEEE PES General Meeting | Conference & Exposition","volume":"109 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":"132077909","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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