Pub Date : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6688003
Younghee Park, D. Nicol, Huaiyu Zhu, Cheol Won Lee
Malware can disrupt the operation of services in advanced metering infrastructure (AMI), which is at risk due to connectivity with the global Internet. In motion, malware may hide within the data payloads of legitimate AMI control traffic, implying the need for deep packet inspection. Some of the inspections one may make look for consistency with respect to data available only at the application layer, requiring one to position the analysis high in the protocol stack. Towards this end we propose a policy engine that examines both ingress and egress traffic to the AMI application layer. Policy engine rules may refer to the structure and behavior of the AMI protocol, and may also perform multi-stage analysis of data payloads looking for evidence that executable code is carried, rather than data. Our experimental results demonstrate that the policy engine is able to accurately distinguish between legitimate traffic and malware bearing traffic.
{"title":"Prevention of malware propagation in AMI","authors":"Younghee Park, D. Nicol, Huaiyu Zhu, Cheol Won Lee","doi":"10.1109/SmartGridComm.2013.6688003","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6688003","url":null,"abstract":"Malware can disrupt the operation of services in advanced metering infrastructure (AMI), which is at risk due to connectivity with the global Internet. In motion, malware may hide within the data payloads of legitimate AMI control traffic, implying the need for deep packet inspection. Some of the inspections one may make look for consistency with respect to data available only at the application layer, requiring one to position the analysis high in the protocol stack. Towards this end we propose a policy engine that examines both ingress and egress traffic to the AMI application layer. Policy engine rules may refer to the structure and behavior of the AMI protocol, and may also perform multi-stage analysis of data payloads looking for evidence that executable code is carried, rather than data. Our experimental results demonstrate that the policy engine is able to accurately distinguish between legitimate traffic and malware bearing traffic.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116667305","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 : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6687982
Fabien Sacuto, F. Labeau, B. Agba
The partitioned Markov chain is a sample noise model that can represent impulsive noise in power substation including the time-correlation between the samples. In order to use this model, algorithms are needed to detect and to estimate the impulses characteristics, such as the duration, the samples values and the occurrence times of the impulses. Unsupervised learning of these characteristics is very complex, we propose then to use the fuzzy C-means algorithm to analyze impulses from substation measurements and to configure the partitioned Markov chain model by instantiating the transition matrix and by estimating the parameters of the Gaussian distributions associated with the Markov states. After simulating sequences of samples with our model, we noticed that the distribution of the impulsive noise characteristics and the power spectrum of the impulses are satisfyingly close to the measurements. The fuzzy C-means algorithm is appropriate to estimate the parameters required by the partitioned Markov chain model and to reduce the complexity of the parameter estimation.
{"title":"Fuzzy C-means algorithm for parameter estimation of partitioned Markov chain impulsive noise model","authors":"Fabien Sacuto, F. Labeau, B. Agba","doi":"10.1109/SmartGridComm.2013.6687982","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6687982","url":null,"abstract":"The partitioned Markov chain is a sample noise model that can represent impulsive noise in power substation including the time-correlation between the samples. In order to use this model, algorithms are needed to detect and to estimate the impulses characteristics, such as the duration, the samples values and the occurrence times of the impulses. Unsupervised learning of these characteristics is very complex, we propose then to use the fuzzy C-means algorithm to analyze impulses from substation measurements and to configure the partitioned Markov chain model by instantiating the transition matrix and by estimating the parameters of the Gaussian distributions associated with the Markov states. After simulating sequences of samples with our model, we noticed that the distribution of the impulsive noise characteristics and the power spectrum of the impulses are satisfyingly close to the measurements. The fuzzy C-means algorithm is appropriate to estimate the parameters required by the partitioned Markov chain model and to reduce the complexity of the parameter estimation.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121967125","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 : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6687991
William Niemira, R. Bobba, P. Sauer, W. Sanders
It is critical that state estimators used in the power grid output accurate results even in the presence of erroneous measurement data. Traditional bad data detection is designed to perform well against isolated random errors. Interacting bad measurements, such as malicious data injection attacks, may be difficult to detect. In this work, we analyze the sensitivities of specific power system quantities to attacks. We compare real and reactive flow and injection measurements as potential indicators of attack. The use of parameter estimation as a means of detecting attack is also investigated. For this the state vector is augmented with known system parameters, allowing both to be estimated simultaneously. Perturbing the system topology is shown to enhance detectability through parameter estimation.
{"title":"Malicious data detection in state estimation leveraging system losses & estimation of perturbed parameters","authors":"William Niemira, R. Bobba, P. Sauer, W. Sanders","doi":"10.1109/SmartGridComm.2013.6687991","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6687991","url":null,"abstract":"It is critical that state estimators used in the power grid output accurate results even in the presence of erroneous measurement data. Traditional bad data detection is designed to perform well against isolated random errors. Interacting bad measurements, such as malicious data injection attacks, may be difficult to detect. In this work, we analyze the sensitivities of specific power system quantities to attacks. We compare real and reactive flow and injection measurements as potential indicators of attack. The use of parameter estimation as a means of detecting attack is also investigated. For this the state vector is augmented with known system parameters, allowing both to be estimated simultaneously. Perturbing the system topology is shown to enhance detectability through parameter estimation.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123063680","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 : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6688011
C. L. Prete, B. Hobbs
This paper considers the potential development of a microgrid in a market served by a vertically integrated electric utility, regulated based on cost of service. The interaction among the utility, the microgrid developer and consumers potentially representing the microgrid's load is assessed in the framework of cooperative game theory, assuming exchangeable utility. We present scenarios based on different underlying assumptions, showing when microgrid development might be beneficial and how it would affect market prices, costs and benefits to the various parties in the network. We also discuss possible regulatory tools that could be used to align private objectives with social welfare maximization.
{"title":"Modeling economic interactions between microgrids and electric utilities: A regulator's perspective","authors":"C. L. Prete, B. Hobbs","doi":"10.1109/SmartGridComm.2013.6688011","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6688011","url":null,"abstract":"This paper considers the potential development of a microgrid in a market served by a vertically integrated electric utility, regulated based on cost of service. The interaction among the utility, the microgrid developer and consumers potentially representing the microgrid's load is assessed in the framework of cooperative game theory, assuming exchangeable utility. We present scenarios based on different underlying assumptions, showing when microgrid development might be beneficial and how it would affect market prices, costs and benefits to the various parties in the network. We also discuss possible regulatory tools that could be used to align private objectives with social welfare maximization.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134143834","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 : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6688050
S. Sojoudi, J. Lavaei
This paper is concerned with the convexification of the optimal power flow (OPF) problem. We have previously shown that this highly nonconvex problem can be solved efficiently via a convex relaxation after two approximations: (i) adding a sufficient number of virtual phase shifters to the network topology, and (ii) relaxing the power balance equations to inequality constraints. The objective of the present paper is to first provide a better understanding of the implications of Approximation (i) and then remove Approximation (ii). To this end, we investigate the effect of virtual phase shifters on the feasible set of OPF by thoroughly examining a cyclic system. We then show that OPF can be convexified under only Approximation (i), provided some mild assumptions are satisfied. Although this paper mainly focuses on OPF, the results developed here can be applied to several OPF-based emerging optimization problems for future electrical grids.
{"title":"Convexification of optimal power flow problem by means of phase shifters","authors":"S. Sojoudi, J. Lavaei","doi":"10.1109/SmartGridComm.2013.6688050","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6688050","url":null,"abstract":"This paper is concerned with the convexification of the optimal power flow (OPF) problem. We have previously shown that this highly nonconvex problem can be solved efficiently via a convex relaxation after two approximations: (i) adding a sufficient number of virtual phase shifters to the network topology, and (ii) relaxing the power balance equations to inequality constraints. The objective of the present paper is to first provide a better understanding of the implications of Approximation (i) and then remove Approximation (ii). To this end, we investigate the effect of virtual phase shifters on the feasible set of OPF by thoroughly examining a cyclic system. We then show that OPF can be convexified under only Approximation (i), provided some mild assumptions are satisfied. Although this paper mainly focuses on OPF, the results developed here can be applied to several OPF-based emerging optimization problems for future electrical grids.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131453256","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 : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6687937
Mashud Hyder, K. Mahata
The use of conventional power flow measurements along with the phasor measurements from newly developed PMUs help us to achieve a cost effective solution for fault localization in power transmission network. However, the development of a methodology for the joint optimal placement of PMUs and power flow units in a transmission network is challenging. To this aim, we have proposed an optimization problem which can be solved using integer linear programming (ILP) implementation. We found that under mild assumptions we can develop a linear mathematical equation for fault localization by using the data from measurement units. The performance is evaluated by applying it for fault detection in IEEE bus systems.
{"title":"On measurement unit placement for smart electrical grid fault localization","authors":"Mashud Hyder, K. Mahata","doi":"10.1109/SmartGridComm.2013.6687937","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6687937","url":null,"abstract":"The use of conventional power flow measurements along with the phasor measurements from newly developed PMUs help us to achieve a cost effective solution for fault localization in power transmission network. However, the development of a methodology for the joint optimal placement of PMUs and power flow units in a transmission network is challenging. To this aim, we have proposed an optimization problem which can be solved using integer linear programming (ILP) implementation. We found that under mild assumptions we can develop a linear mathematical equation for fault localization by using the data from measurement units. The performance is evaluated by applying it for fault detection in IEEE bus systems.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114121238","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 : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6687946
I. S. Bayram, G. Michailidis, M. Devetsikiotis
The mainstream adoption of Electric and Plug-in Hybrid Electric Vehicles (EVs/PHEVs) requires the wide deployment of public charging stations of large scale. Such facilities are essential for this goal, and probably represent the only option for drivers living in densely populated areas. They could also provide complementary service to extend the EV range for drivers who also have access to domicile charging. On the other hand, since these stations will mainly operate during the day, stochastic customer demand exerted on the power grid may threaten its reliability. Hence, the problem of electric power resource provisioning should be carefully considered. In this study, we propose a capacity planning framework by exploiting the stochastic behavior of customer demand at each charging slot in large capacity stations. Our framework assigns a constant power to each charging slot. Thus, aggregated stochastic demand is approximated by a deterministic quantity, at the price of denying service to a very small percentage of customers. Our model leads to significant savings in power provisioning and provides critical insights about the design of charging station.
{"title":"Electric power resource provisioning for large scale public EV charging facilities","authors":"I. S. Bayram, G. Michailidis, M. Devetsikiotis","doi":"10.1109/SmartGridComm.2013.6687946","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6687946","url":null,"abstract":"The mainstream adoption of Electric and Plug-in Hybrid Electric Vehicles (EVs/PHEVs) requires the wide deployment of public charging stations of large scale. Such facilities are essential for this goal, and probably represent the only option for drivers living in densely populated areas. They could also provide complementary service to extend the EV range for drivers who also have access to domicile charging. On the other hand, since these stations will mainly operate during the day, stochastic customer demand exerted on the power grid may threaten its reliability. Hence, the problem of electric power resource provisioning should be carefully considered. In this study, we propose a capacity planning framework by exploiting the stochastic behavior of customer demand at each charging slot in large capacity stations. Our framework assigns a constant power to each charging slot. Thus, aggregated stochastic demand is approximated by a deterministic quantity, at the price of denying service to a very small percentage of customers. Our model leads to significant savings in power provisioning and provides critical insights about the design of charging station.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123779079","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 : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6687933
Dae-Hyun Choi, Le Xie
This paper formulates and analyzes the impact of power transmission network topology error on real-time electricity market prices. We consider the scenario in which the undetected false status of circuit breakers from topology error processing may lead to wrong modeling of real-time network topology, which, in turn, misleads the results of state estimation and real-time economic dispatch. In particular, we focus on the economic impact of this circuit breaker-induced network topology error on locational marginal price (LMP). The primary goal of this paper is to derive a simple LMP sensitivity index that accounts for the relationship between the change in network topology and LMP. The proposed sensitivity index provides system operators a simple but effective screening of the impact of topology errors on real-time LMP. The validity of the derived sensitivity index is verified and illustrated with numerical examples in the IEEE-14 bus system.
{"title":"Impact analysis of locational marginal price subject to power system topology errors","authors":"Dae-Hyun Choi, Le Xie","doi":"10.1109/SmartGridComm.2013.6687933","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6687933","url":null,"abstract":"This paper formulates and analyzes the impact of power transmission network topology error on real-time electricity market prices. We consider the scenario in which the undetected false status of circuit breakers from topology error processing may lead to wrong modeling of real-time network topology, which, in turn, misleads the results of state estimation and real-time economic dispatch. In particular, we focus on the economic impact of this circuit breaker-induced network topology error on locational marginal price (LMP). The primary goal of this paper is to derive a simple LMP sensitivity index that accounts for the relationship between the change in network topology and LMP. The proposed sensitivity index provides system operators a simple but effective screening of the impact of topology errors on real-time LMP. The validity of the derived sensitivity index is verified and illustrated with numerical examples in the IEEE-14 bus system.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121784132","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 : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6687975
M. Höfling, C. G. Mills, M. Menth
We develop and analyze algorithms that reduce the storage capacity required by SeDAX (Secure Data-centric Application eXtensible) in the presence of simultaneous node failures. The SeDAX infrastructure for smart grids uses data redundancy for a high level of reliability. It is an information-centric approach using resilient data forwarding in a Delaunay triangulated overlay. While SeDAX's data forwarding scheme is well understood, there is no study that considers the SeDAX storage capacity necessary to survive multiple node failures. Our results are compared with the theoretical lower bound of SeDAX and the lower bound of an idealized storage system. The presented algorithms can be used to reduce storage requirements of SeDAX in practice.
{"title":"Analyzing storage requirements of the resilient information-centric SeDAX architecture","authors":"M. Höfling, C. G. Mills, M. Menth","doi":"10.1109/SmartGridComm.2013.6687975","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6687975","url":null,"abstract":"We develop and analyze algorithms that reduce the storage capacity required by SeDAX (Secure Data-centric Application eXtensible) in the presence of simultaneous node failures. The SeDAX infrastructure for smart grids uses data redundancy for a high level of reliability. It is an information-centric approach using resilient data forwarding in a Delaunay triangulated overlay. While SeDAX's data forwarding scheme is well understood, there is no study that considers the SeDAX storage capacity necessary to survive multiple node failures. Our results are compared with the theoretical lower bound of SeDAX and the lower bound of an idealized storage system. The presented algorithms can be used to reduce storage requirements of SeDAX in practice.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127904867","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 : 2013-12-19DOI: 10.1109/SmartGridComm.2013.6687935
Jonas Wäfler, P. Heegaard
The pervasive use of information and communication technology (ICT) in the future power grid introduces new dependencies and new failure patterns. The simultaneous failure of several nodes may become more likely as devices get more complex and increasingly interconnected. Several studies investigated the behavior of power grids under simultaneous failures. However, the commonly used measure to quantify the outcome is agnostic to important characteristics of the power grid and its interpretation for dependability analysis remains unclear. We introduce two new measures which take the most fundamental characteristics of the power grid into account: the connectivity to power sources and the balancing of load and production. We analyze the two measures in scenarios with random and intentional node failures and conclude, that they are suitable for structural dependability and survivability analysis of power grids. Further, we use the new measures to quantify the potential dependability increase when using the smart grid services Demand Response (DR) and Distributed Energy Resources for failure mitigation. We find that a load reduction with DR by 20% may already achieve a large part of the possible dependability increase with Demand Response.
{"title":"Structural dependability analysis in smart grid under simultaneous failures","authors":"Jonas Wäfler, P. Heegaard","doi":"10.1109/SmartGridComm.2013.6687935","DOIUrl":"https://doi.org/10.1109/SmartGridComm.2013.6687935","url":null,"abstract":"The pervasive use of information and communication technology (ICT) in the future power grid introduces new dependencies and new failure patterns. The simultaneous failure of several nodes may become more likely as devices get more complex and increasingly interconnected. Several studies investigated the behavior of power grids under simultaneous failures. However, the commonly used measure to quantify the outcome is agnostic to important characteristics of the power grid and its interpretation for dependability analysis remains unclear. We introduce two new measures which take the most fundamental characteristics of the power grid into account: the connectivity to power sources and the balancing of load and production. We analyze the two measures in scenarios with random and intentional node failures and conclude, that they are suitable for structural dependability and survivability analysis of power grids. Further, we use the new measures to quantify the potential dependability increase when using the smart grid services Demand Response (DR) and Distributed Energy Resources for failure mitigation. We find that a load reduction with DR by 20% may already achieve a large part of the possible dependability increase with Demand Response.","PeriodicalId":136434,"journal":{"name":"2013 IEEE International Conference on Smart Grid Communications (SmartGridComm)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115621556","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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