The Vehicle-To-Grid (V2G) technology allows plug-in electric vehicles (PEVs) to act like an energy provider besides being a consumer. A PEV, being connected to the smart grid, can either charge its battery by consuming electricity from the grid or discharge the stored electricity from the battery to the grid. It can also participate in the frequency regulation service of the grid. Executing the aforementioned operations in a non-controlled fashion may come with problems on the grid functionality. For safe and sustainable functioning of the grid, controlling the operations is very crucial. In this paper, we are offering an approach for vehicle-to-grid management using constraint-based formal modeling. The approach is centered around an aggregator that collects all the involved parties' constraints and preferences. The aggregator then finds a management plan, i.e., a schedule of V2G services for the PEVs by satisfying the given constraints besides its own requirements. We apply satisfiability modulo theories (SMT) to synthesize the schedule as a satisfaction of the constraints. Our evaluation results show that the formalization can be efficiently solved for problems with thousands of PEVs.
{"title":"A formal model for sustainable vehicle-to-grid management","authors":"M. Rahman, Fadi Mohsen, E. Al-Shaer","doi":"10.1145/2516930.2516937","DOIUrl":"https://doi.org/10.1145/2516930.2516937","url":null,"abstract":"The Vehicle-To-Grid (V2G) technology allows plug-in electric vehicles (PEVs) to act like an energy provider besides being a consumer. A PEV, being connected to the smart grid, can either charge its battery by consuming electricity from the grid or discharge the stored electricity from the battery to the grid. It can also participate in the frequency regulation service of the grid. Executing the aforementioned operations in a non-controlled fashion may come with problems on the grid functionality. For safe and sustainable functioning of the grid, controlling the operations is very crucial. In this paper, we are offering an approach for vehicle-to-grid management using constraint-based formal modeling. The approach is centered around an aggregator that collects all the involved parties' constraints and preferences. The aggregator then finds a management plan, i.e., a schedule of V2G services for the PEVs by satisfying the given constraints besides its own requirements. We apply satisfiability modulo theories (SMT) to synthesize the schedule as a satisfaction of the constraints. Our evaluation results show that the formalization can be efficiently solved for problems with thousands of PEVs.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115057575","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}
G. Danezis, C. Fournet, Markulf Kohlweiss, Santiago Zanella-Béguelin
We design and prototype protocols for processing smart-meter readings while preserving user privacy. We provide support for computing non-linear functions on encrypted readings, implemented by adapting to our setting efficient secret-sharing-based secure multi-party computation techniques. Meter readings are jointly processed by a (public) storage service and a few independent authorities, each owning an additive share of the readings. For non-linear processing, these parties consume pre-shared materials, produced by an off-line trusted third party. This party never processes private readings; it may be implemented using trusted hardware or somewhat homomorphic encryption. The protocol involves minimal, off-line support from the meters---a few keyed hash computations and no communication overhead.
{"title":"Smart meter aggregation via secret-sharing","authors":"G. Danezis, C. Fournet, Markulf Kohlweiss, Santiago Zanella-Béguelin","doi":"10.1145/2516930.2516944","DOIUrl":"https://doi.org/10.1145/2516930.2516944","url":null,"abstract":"We design and prototype protocols for processing smart-meter readings while preserving user privacy. We provide support for computing non-linear functions on encrypted readings, implemented by adapting to our setting efficient secret-sharing-based secure multi-party computation techniques. Meter readings are jointly processed by a (public) storage service and a few independent authorities, each owning an additive share of the readings. For non-linear processing, these parties consume pre-shared materials, produced by an off-line trusted third party. This party never processes private readings; it may be implemented using trusted hardware or somewhat homomorphic encryption. The protocol involves minimal, off-line support from the meters---a few keyed hash computations and no communication overhead.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129013475","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}
ZigBee Smart Energy is the world's leading standard for interoperable products that monitor, control, inform and automate the delivery and use of energy and water. The ZigBee Smart Energy Profile (SEP) specification uses elliptic curve cryptography (ECC) for implementing certificate-based key establishment (CBKE) between communicating devices. This paper presents the design, implementation, and evaluation of OpenECC, the first open-source library supporting ECC-based protocols for ZigBee SEP version 1.x. The experimental results demonstrate the high performance and small memory footprint of the OpenECC library when deployed on the current generation of Zigbee Smart Energy platform. Our work is the first step towards securing ZigBee Smart Energy applications using open-source libraries.
{"title":"Securing ZigBee smart energy profile 1.x with OpenECC library","authors":"Xinxin Fan, G. Gong","doi":"10.1145/2516930.2516946","DOIUrl":"https://doi.org/10.1145/2516930.2516946","url":null,"abstract":"ZigBee Smart Energy is the world's leading standard for interoperable products that monitor, control, inform and automate the delivery and use of energy and water. The ZigBee Smart Energy Profile (SEP) specification uses elliptic curve cryptography (ECC) for implementing certificate-based key establishment (CBKE) between communicating devices. This paper presents the design, implementation, and evaluation of OpenECC, the first open-source library supporting ECC-based protocols for ZigBee SEP version 1.x. The experimental results demonstrate the high performance and small memory footprint of the OpenECC library when deployed on the current generation of Zigbee Smart Energy platform. Our work is the first step towards securing ZigBee Smart Energy applications using open-source libraries.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132002283","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}
The C-DAX project aims at providing a secure overlay network, as an overlay over an IP network, that provides an information-centric network (ICN) tailored to the needs and the capabilities of smart grids. This paper addresses how end-to-end security can be enforced in information-centric networks by proposing a protocol based on the concept of identity-based encryption, a type of public-key cryptography.
{"title":"A security protocol for information-centric networking in smart grids","authors":"B. Vieira, E. Poll","doi":"10.1145/2516930.2516932","DOIUrl":"https://doi.org/10.1145/2516930.2516932","url":null,"abstract":"The C-DAX project aims at providing a secure overlay network, as an overlay over an IP network, that provides an information-centric network (ICN) tailored to the needs and the capabilities of smart grids. This paper addresses how end-to-end security can be enforced in information-centric networks by proposing a protocol based on the concept of identity-based encryption, a type of public-key cryptography.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124769359","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}
This paper proposes an authentication and key management framework to strengthen the security level of the advanced metering infrastructure based on the DLMS/COSEM standard. The current DLMS/COSEM standard does not specify detailed secret key generation and distribution procedures, which induce a critical issues regarding interoperability in secure communication among AMI devices. Moreover, the protocol suffers from a key distribution problem, which can expose a session secret key supposed to be shared only by two devices to a third party node. The basic ideas are that smart meters and data collection systems perform the authentication and key exchange with AMI server using existing Extensible Authentication Protocol (EAP) standard, and DLMS/COSEM secret keys are created and shared securely using pre-formed secure channels. We show how the proposed framework can be realized in advanced metering infrastructure using existing standard protocols and provide preliminary security and performance comparisons with the existing related proposals.
{"title":"DLMS/COSEM security level enhancement to construct secure advanced metering infrastructure","authors":"Jaeduck Choi, Incheol Shin","doi":"10.1145/2516930.2516949","DOIUrl":"https://doi.org/10.1145/2516930.2516949","url":null,"abstract":"This paper proposes an authentication and key management framework to strengthen the security level of the advanced metering infrastructure based on the DLMS/COSEM standard. The current DLMS/COSEM standard does not specify detailed secret key generation and distribution procedures, which induce a critical issues regarding interoperability in secure communication among AMI devices. Moreover, the protocol suffers from a key distribution problem, which can expose a session secret key supposed to be shared only by two devices to a third party node. The basic ideas are that smart meters and data collection systems perform the authentication and key exchange with AMI server using existing Extensible Authentication Protocol (EAP) standard, and DLMS/COSEM secret keys are created and shared securely using pre-formed secure channels. We show how the proposed framework can be realized in advanced metering infrastructure using existing standard protocols and provide preliminary security and performance comparisons with the existing related proposals.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131140005","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}
In recent years a number of protocols have been suggested toward privacy-preserving aggregation of smart meter data, allowing electricity network operators to perform a large part of grid maintenance and administrative operations without having to touch any privacy-sensitive data. In light of upcoming European legislation, this approach has gained quite some attention. However, to allow such protocols to have a chance to make it into a real system, it is vital to add credibility by demonstrating that the approach scales, is reasonably robust, and can be integrated into the existing and planned smart metering chains. This paper presents results from integration and scalability tests performed on 100 DLMS/COSEM smart meters in collaboration with a meter manufacturer and a Dutch utility. We outline the use cases, lessons learned, and choices that had to be made to allow the protocols to run in a real system, as well as some privacy challenges that cannot be covered by this technology.
{"title":"Implementation of privacy-friendly aggregation for the smart grid","authors":"Benessa Defend, K. Kursawe","doi":"10.1145/2516930.2516936","DOIUrl":"https://doi.org/10.1145/2516930.2516936","url":null,"abstract":"In recent years a number of protocols have been suggested toward privacy-preserving aggregation of smart meter data, allowing electricity network operators to perform a large part of grid maintenance and administrative operations without having to touch any privacy-sensitive data. In light of upcoming European legislation, this approach has gained quite some attention. However, to allow such protocols to have a chance to make it into a real system, it is vital to add credibility by demonstrating that the approach scales, is reasonably robust, and can be integrated into the existing and planned smart metering chains. This paper presents results from integration and scalability tests performed on 100 DLMS/COSEM smart meters in collaboration with a meter manufacturer and a Dutch utility. We outline the use cases, lessons learned, and choices that had to be made to allow the protocols to run in a real system, as well as some privacy challenges that cannot be covered by this technology.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114852964","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}
Because of a lack of attack signatures and different forms of attacks, signature-based network intrusion detection systems currently provide insufficient protection for industrial control traffic. A combination of two anomaly detection approaches found in the literature, one based on network flows and the other on protocol specific deep-packet inspection, seems to be able to detect many expected threats. Deep-packet inspection cannot be used however, when payloads cannot be read because they are encrypted, or the protocol is unfamiliar. This paper proposes an intrusion detection approach that does not need to inspect the payload, and can still perform much the same function as the deep-packet approach. It consists of three steps: separate insertions caused by commands from the background of polling cycle traffic, recognize and react on known insertions, and alert on unknown insertions. The approach is implemented using searches for series of packets, based on the edit distance from approximate string matching. Tests show that this implementation can perform the steps necessary for the approach.
{"title":"Detecting intrusions in encrypted control traffic","authors":"Maarten Hoeve","doi":"10.1145/2516930.2516945","DOIUrl":"https://doi.org/10.1145/2516930.2516945","url":null,"abstract":"Because of a lack of attack signatures and different forms of attacks, signature-based network intrusion detection systems currently provide insufficient protection for industrial control traffic. A combination of two anomaly detection approaches found in the literature, one based on network flows and the other on protocol specific deep-packet inspection, seems to be able to detect many expected threats. Deep-packet inspection cannot be used however, when payloads cannot be read because they are encrypted, or the protocol is unfamiliar.\u0000 This paper proposes an intrusion detection approach that does not need to inspect the payload, and can still perform much the same function as the deep-packet approach. It consists of three steps: separate insertions caused by commands from the background of polling cycle traffic, recognize and react on known insertions, and alert on unknown insertions. The approach is implemented using searches for series of packets, based on the edit distance from approximate string matching. Tests show that this implementation can perform the steps necessary for the approach.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126450852","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}
Smart metering systems obtain fine-grained consumption data of their users. This allows for effective load balancing, but at the same time threatens consumers' privacy. Since the electricity provider only needs the characteristics of a region, not individuals, approaches like one by Mármol et al. suggest to aggregate data to protect consumer privacy. However, an implementation of such an approach also has to consider the legal and regulatory situation. In Germany, the technical guideline TR-03109 issued by the Federal Office for Information Security specifies demands which have to be fulfilled so that a smart meter gateway can be certified for use. These specifications imply limitations to the protocol design. Within this paper, we discuss the applicability of the method presented by Mármol et al. under consideration of the German Smart Metering guideline. Where conformity is not given, we offer a solution to overcome these restrictions by adapting their method and introduce a third party aggregator who does not have to be trusted. Our method comes with additional communication effort but behaves well in terms of memory and computational overhead. The achieved privacy level outreaches a purely pseudonymous value transmission. Also it does not contradict the postulations of TR-03109, making it an applicable choice for privacy protection in real-world smart metering systems.
智能计量系统获取用户的细粒度消费数据。这允许有效的负载平衡，但同时威胁到消费者的隐私。由于电力供应商只需要一个地区的特征，而不需要个人的特征，因此Mármol等人的方法建议汇总数据以保护消费者隐私。但是，这种方法的实施还必须考虑到法律和监管情况。在德国，联邦信息安全办公室(Federal Office for Information Security)发布的技术指南TR-03109规定了智能电表网关获得使用认证必须满足的要求。这些规范暗示了协议设计的局限性。在本文中，我们讨论了Mármol等人在考虑德国智能计量指南的情况下提出的方法的适用性。在没有给出一致性的情况下，我们提供了一个解决方案，通过调整他们的方法来克服这些限制，并引入一个不必被信任的第三方聚合器。我们的方法需要额外的通信工作，但在内存和计算开销方面表现良好。实现的隐私级别超出了纯粹的假名价值传输。此外，它与TR-03109的规定并不矛盾，使其成为现实世界智能计量系统中隐私保护的适用选择。
{"title":"Protection of consumer data in the smart grid compliant with the German smart metering guideline","authors":"A. Biselli, Elke Franz, M. P. Coutinho","doi":"10.1145/2516930.2516933","DOIUrl":"https://doi.org/10.1145/2516930.2516933","url":null,"abstract":"Smart metering systems obtain fine-grained consumption data of their users. This allows for effective load balancing, but at the same time threatens consumers' privacy. Since the electricity provider only needs the characteristics of a region, not individuals, approaches like one by Mármol et al. suggest to aggregate data to protect consumer privacy. However, an implementation of such an approach also has to consider the legal and regulatory situation. In Germany, the technical guideline TR-03109 issued by the Federal Office for Information Security specifies demands which have to be fulfilled so that a smart meter gateway can be certified for use. These specifications imply limitations to the protocol design. Within this paper, we discuss the applicability of the method presented by Mármol et al. under consideration of the German Smart Metering guideline. Where conformity is not given, we offer a solution to overcome these restrictions by adapting their method and introduce a third party aggregator who does not have to be trusted. Our method comes with additional communication effort but behaves well in terms of memory and computational overhead. The achieved privacy level outreaches a purely pseudonymous value transmission. Also it does not contradict the postulations of TR-03109, making it an applicable choice for privacy protection in real-world smart metering systems.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"29 19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121154477","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}
Hui Lin, A. Slagell, Z. Kalbarczyk, P. Sauer, R. Iyer
In the current generation of SCADA (Supervisory Control And Data Acquisition) systems used in power grids, a sophisticated attacker can exploit system vulnerabilities and use a legitimate maliciously crafted command to cause a wide range of system changes that traditional contingency analysis does not consider and remedial action schemes cannot handle. To detect such malicious commands, we propose a semantic analysis framework based on a distributed network of intrusion detection systems (IDSes). The framework combines system knowledge of both cyber and physical infrastructure in power grid to help IDS to estimate execution consequences of control commands, thus to reveal attacker's malicious intentions. We evaluated the approach on the IEEE 30-bus system. Our experiments demonstrate that: (i) by opening 3 transmission lines, an attacker can avoid detection by the traditional contingency analysis and instantly put the tested 30-bus system into an insecure state and (ii) the semantic analysis provides reliable detection of malicious commands with a small amount of analysis time.
{"title":"Semantic security analysis of SCADA networks to detect malicious control commands in power grids","authors":"Hui Lin, A. Slagell, Z. Kalbarczyk, P. Sauer, R. Iyer","doi":"10.1145/2516930.2516947","DOIUrl":"https://doi.org/10.1145/2516930.2516947","url":null,"abstract":"In the current generation of SCADA (Supervisory Control And Data Acquisition) systems used in power grids, a sophisticated attacker can exploit system vulnerabilities and use a legitimate maliciously crafted command to cause a wide range of system changes that traditional contingency analysis does not consider and remedial action schemes cannot handle. To detect such malicious commands, we propose a semantic analysis framework based on a distributed network of intrusion detection systems (IDSes). The framework combines system knowledge of both cyber and physical infrastructure in power grid to help IDS to estimate execution consequences of control commands, thus to reveal attacker's malicious intentions. We evaluated the approach on the IEEE 30-bus system. Our experiments demonstrate that: (i) by opening 3 transmission lines, an attacker can avoid detection by the traditional contingency analysis and instantly put the tested 30-bus system into an insecure state and (ii) the semantic analysis provides reliable detection of malicious commands with a small amount of analysis time.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130742989","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}
The electrical power grid is in the midst of a breathtaking transformation into the "Smart Grid". A key element is development of the Advanced Metering Infrastructure (AMI),which is changing the way tilities interact with smart meters at customer sites. However, with the technology comes the new risks of cyber-attacks that could exploit vulnerabilities in different parts of the communication layers, and potentially affect significant portions of the power grid. This paper proposes a novel distributed monitoring architecture that is capable of selecting a subset of smart meters used as intrusion detection sensors -- a subset selected to minimize the number of meters needed while keeping the communication. Our architecture enables recovery of collided packets (that are subject to packet inspection), improving the overall reliability and accuracy of distributed monitoring.
{"title":"A distributed monitoring architecture for AMIs: minimizing the number of monitoring nodes and enabling collided packet recovery","authors":"Incheol Shin, J. Huh, Yuseok Jeon, D. Nicol","doi":"10.1145/2516930.2516948","DOIUrl":"https://doi.org/10.1145/2516930.2516948","url":null,"abstract":"The electrical power grid is in the midst of a breathtaking transformation into the \"Smart Grid\". A key element is development of the Advanced Metering Infrastructure (AMI),which is changing the way tilities interact with smart meters at customer sites. However, with the technology comes the new risks of cyber-attacks that could exploit vulnerabilities in different parts of the communication layers, and potentially affect significant portions of the power grid. This paper proposes a novel distributed monitoring architecture that is capable of selecting a subset of smart meters used as intrusion detection sensors -- a subset selected to minimize the number of meters needed while keeping the communication. Our architecture enables recovery of collided packets (that are subject to packet inspection), improving the overall reliability and accuracy of distributed monitoring.","PeriodicalId":303004,"journal":{"name":"ACM workshop on Smart Energy Grid Security","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124164475","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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