J. Amelot, J. Fletcher, Y. Li-Baboud, D. Anand, Clement Vasseur, J. Moyne
The numerous time synchronization performance requirements in the Smart Grid necessitates a set of common metrics and test methods. The test methods help to verify the ability of the network system and its components to meet the power industry's accuracy, reliability and interoperability criteria for next-generation substations. In order to develop viable metrics and test methods, an IEEE 1588 Testbed for the power industry has been established. To ease the challenges of testing, monitoring and analysis of the results, a software-based testing dashboard was designed and implemented. The dashboard streamlines the performance testing process by converging multiple tests for accuracy, reliability and interoperability into a centralized interface. The dashboard enables real-time visualization and analysis of the results. The paper details the design and implementation of the IEEE 1588 Power Industry Performance Testing Dashboard as well as an update of the preliminary findings from the testbed.
{"title":"An IEEE 1588 Performance Testing Dashboard for Power Industry requirements","authors":"J. Amelot, J. Fletcher, Y. Li-Baboud, D. Anand, Clement Vasseur, J. Moyne","doi":"10.1145/2393091.2393131","DOIUrl":"https://doi.org/10.1145/2393091.2393131","url":null,"abstract":"The numerous time synchronization performance requirements in the Smart Grid necessitates a set of common metrics and test methods. The test methods help to verify the ability of the network system and its components to meet the power industry's accuracy, reliability and interoperability criteria for next-generation substations. In order to develop viable metrics and test methods, an IEEE 1588 Testbed for the power industry has been established. To ease the challenges of testing, monitoring and analysis of the results, a software-based testing dashboard was designed and implemented. The dashboard streamlines the performance testing process by converging multiple tests for accuracy, reliability and interoperability into a centralized interface. The dashboard enables real-time visualization and analysis of the results. The paper details the design and implementation of the IEEE 1588 Power Industry Performance Testing Dashboard as well as an update of the preliminary findings from the testbed.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125964271","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 : 2011-11-07DOI: 10.1109/ISPCS.2011.6070149
P. Ferrari, A. Flammini, S. Rinaldi, E. Sisinni
In the last years, Wireless Sensor Networks experienced a great success in the research community and also the interest of the industrial world seems increasing, as demonstrated by the definition of several standards (e.g. WirelessHART and ISA100.11a). Up to now, network robustness and optimization of the power consumption are the key point of a sensors network. However, the recent technology improvements offer a plenty of processing power and, in this scenario, some background aspects (e.g. advanced networking and time synchronization) cannot be ignored. This paper focuses its attention on synchronization on Wireless Sensor Network based on IPv6 protocol. The integration of IEEE 1588 protocol into this scenario has been analyzed. The synchronization stack has been implemented over a performing platform, which achieves a timestamping accuracy in the order of ±500 ns. However, the synchronization capabilities of the overall system is in the order of 1 ms.
{"title":"Time distribution in IPv6 Wireless Sensor Networks","authors":"P. Ferrari, A. Flammini, S. Rinaldi, E. Sisinni","doi":"10.1109/ISPCS.2011.6070149","DOIUrl":"https://doi.org/10.1109/ISPCS.2011.6070149","url":null,"abstract":"In the last years, Wireless Sensor Networks experienced a great success in the research community and also the interest of the industrial world seems increasing, as demonstrated by the definition of several standards (e.g. WirelessHART and ISA100.11a). Up to now, network robustness and optimization of the power consumption are the key point of a sensors network. However, the recent technology improvements offer a plenty of processing power and, in this scenario, some background aspects (e.g. advanced networking and time synchronization) cannot be ignored. This paper focuses its attention on synchronization on Wireless Sensor Network based on IPv6 protocol. The integration of IEEE 1588 protocol into this scenario has been analyzed. The synchronization stack has been implemented over a performing platform, which achieves a timestamping accuracy in the order of ±500 ns. However, the synchronization capabilities of the overall system is in the order of 1 ms.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125582012","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 : 2011-11-07DOI: 10.1109/ISPCS.2011.6070161
Ryan Zarick, Mikkel Hagen, R. Bartos
Precision Time Protocol (PTP) is a high-precision time synchronization protocol designed to operate over a local area network. PTP, typically referred to as 1588, is defined by the IEEE Standard 1588™-2008 and provides clock synchronization at the nanosecond level. Even though devices with support for 1588 are widely available, there have been few performance studies of such devices. This paper investigates the impact of latency and high bandwidth background traffic on 1588 clock synchronization in a network consisting of both 1588 and non-1588 aware switches. As expected, we found that 1588-aware switches provide higher precision time synchronization in smaller-scale networks. In larger networks with congestion, 1588-aware switches were unable to maintain high accuracy clock synchronization due to the lack of traffic prioritization. Our results also show that having cut-through Enterprise Ethernet switches with prioritization enabled is adequate for maintaining sub-microsecond synchronization.
{"title":"Transparent Clocks vs. Enterprise Ethernet switches","authors":"Ryan Zarick, Mikkel Hagen, R. Bartos","doi":"10.1109/ISPCS.2011.6070161","DOIUrl":"https://doi.org/10.1109/ISPCS.2011.6070161","url":null,"abstract":"Precision Time Protocol (PTP) is a high-precision time synchronization protocol designed to operate over a local area network. PTP, typically referred to as 1588, is defined by the IEEE Standard 1588™-2008 and provides clock synchronization at the nanosecond level. Even though devices with support for 1588 are widely available, there have been few performance studies of such devices. This paper investigates the impact of latency and high bandwidth background traffic on 1588 clock synchronization in a network consisting of both 1588 and non-1588 aware switches. As expected, we found that 1588-aware switches provide higher precision time synchronization in smaller-scale networks. In larger networks with congestion, 1588-aware switches were unable to maintain high accuracy clock synchronization due to the lack of traffic prioritization. Our results also show that having cut-through Enterprise Ethernet switches with prioritization enabled is adequate for maintaining sub-microsecond synchronization.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128398466","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 : 2011-11-07DOI: 10.1109/ISPCS.2011.6070156
B. Hirschler, A. Treytl
The Precision Time Protocol (PTP) specified by IEEE 1588 contains a security extension to properly protect the exchanged information. The purpose of this extension is to detect manipulation and illegitimate replay of PTP messages and consequently prevent malicious attacks. To gain confidence in certain implementations this article presents a basic test suite to validate and verify the IEEE 1588 security extension. Based on an analysis of the security functionality a test setup and basic test cases are presented that allow to test Targets Of Evaluation (TOE) - ordinary as well as transparent clocks - and being able to give evidence about the correct security functionality. Outcome is a set of 13 test cases that cover all aspects of PTP security, namely message protection, mutual authentication and management of security associations.
{"title":"Validation and verification of IEEE 1588 Annex K","authors":"B. Hirschler, A. Treytl","doi":"10.1109/ISPCS.2011.6070156","DOIUrl":"https://doi.org/10.1109/ISPCS.2011.6070156","url":null,"abstract":"The Precision Time Protocol (PTP) specified by IEEE 1588 contains a security extension to properly protect the exchanged information. The purpose of this extension is to detect manipulation and illegitimate replay of PTP messages and consequently prevent malicious attacks. To gain confidence in certain implementations this article presents a basic test suite to validate and verify the IEEE 1588 security extension. Based on an analysis of the security functionality a test setup and basic test cases are presented that allow to test Targets Of Evaluation (TOE) - ordinary as well as transparent clocks - and being able to give evidence about the correct security functionality. Outcome is a set of 13 test cases that cover all aspects of PTP security, namely message protection, mutual authentication and management of security associations.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115848884","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 : 2011-11-07DOI: 10.1109/ISPCS.2011.6070159
T. Murakami, Y. Horiuchi, Kosuke Nishimura
This paper presents a packet filtering mechanism by using packet delay distribution estimation for improving the clock stability of time synchronization with IEEE 1588. We study a packet delay distribution estimation method by using a dedicated probing packet, and discuss the applicability of the estimation method for the clock control mechanism in IEEE 1588 slave nodes. Numerical simulations show that the packet delay distribution estimation method is effective for packet filtering in heavily congested networks.
{"title":"A packet filtering mechanism with a packet delay distribution estimation function for IEEE 1588 time synchronization in a congested network","authors":"T. Murakami, Y. Horiuchi, Kosuke Nishimura","doi":"10.1109/ISPCS.2011.6070159","DOIUrl":"https://doi.org/10.1109/ISPCS.2011.6070159","url":null,"abstract":"This paper presents a packet filtering mechanism by using packet delay distribution estimation for improving the clock stability of time synchronization with IEEE 1588. We study a packet delay distribution estimation method by using a dedicated probing packet, and discuss the applicability of the estimation method for the clock control mechanism in IEEE 1588 slave nodes. Numerical simulations show that the packet delay distribution estimation method is effective for packet filtering in heavily congested networks.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130502457","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 : 2011-11-07DOI: 10.1109/ISPCS.2011.6070162
H. Trsek, J. Jasperneite
Wireless technologies are increasingly deployed in factory automation systems, because they are able to provide several advantages, e. g., a higher level of mobility, more flexibility, and at the same time causing lower costs. However, the requirements of industrial applications in terms of real-time communication can not be satisfied by existing wireless technologies, such as IEEE 802.11Wireless Local Area Networks (WLANs). This is due to their unpredictable behaviour and the introduction of delays beyond acceptable bounds, mainly caused by a non-deterministic medium access. Hence, the proposed wireless communication system provides real-time communication services based on the IEEE 802.11 protocol family. In this paper we present a new isochronous medium access control mechanism, called IsoMAC. The paper addresses IsoMAC and shows how, in combination with a suitable wireless clock synchronization, IsoMAC is able to satisfy the typical constraints of soft real-time flows found on the factory floor. A simulation case study is provided that shows the achievable update times of the proposed combination.
{"title":"An isochronous medium access for real-time wireless communications in industrial automation systems - A use case for wireless clock synchronization","authors":"H. Trsek, J. Jasperneite","doi":"10.1109/ISPCS.2011.6070162","DOIUrl":"https://doi.org/10.1109/ISPCS.2011.6070162","url":null,"abstract":"Wireless technologies are increasingly deployed in factory automation systems, because they are able to provide several advantages, e. g., a higher level of mobility, more flexibility, and at the same time causing lower costs. However, the requirements of industrial applications in terms of real-time communication can not be satisfied by existing wireless technologies, such as IEEE 802.11Wireless Local Area Networks (WLANs). This is due to their unpredictable behaviour and the introduction of delays beyond acceptable bounds, mainly caused by a non-deterministic medium access. Hence, the proposed wireless communication system provides real-time communication services based on the IEEE 802.11 protocol family. In this paper we present a new isochronous medium access control mechanism, called IsoMAC. The paper addresses IsoMAC and shows how, in combination with a suitable wireless clock synchronization, IsoMAC is able to satisfy the typical constraints of soft real-time flows found on the factory floor. A simulation case study is provided that shows the achievable update times of the proposed combination.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132578039","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 : 2011-11-07DOI: 10.1109/ISPCS.2011.6070146
A. Westenberger, Tobias Huck, M. Fritzsche, T. Schwarz, K. Dietmayer
A new approach to precise timestamping and temporal synchronization in a multi-sensor setup is presented. Modern driver assistance systems use an increasing amount of different sensors that do not provide the exact timestamps of the measurements, nor the period of time between two measurements. This paper describes a method to determine these timestamps up to millisecond accuracy. Possible drifts of the internal sensor clocks are taken into account. In addition, a frequent problem are lost measurements that lead to large errors in the timestamping. These framedrops are detected reliably and handled adequately via the method at hand. Finally a method to evaluate the performance of the whole timestamping procedure is described and real-world results are presented.
{"title":"Temporal synchronization in multi-sensor fusion for future driver assistance systems","authors":"A. Westenberger, Tobias Huck, M. Fritzsche, T. Schwarz, K. Dietmayer","doi":"10.1109/ISPCS.2011.6070146","DOIUrl":"https://doi.org/10.1109/ISPCS.2011.6070146","url":null,"abstract":"A new approach to precise timestamping and temporal synchronization in a multi-sensor setup is presented. Modern driver assistance systems use an increasing amount of different sensors that do not provide the exact timestamps of the measurements, nor the period of time between two measurements. This paper describes a method to determine these timestamps up to millisecond accuracy. Possible drifts of the internal sensor clocks are taken into account. In addition, a frequent problem are lost measurements that lead to large errors in the timestamping. These framedrops are detected reliably and handled adequately via the method at hand. Finally a method to evaluate the performance of the whole timestamping procedure is described and real-world results are presented.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129103055","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 : 2011-11-07DOI: 10.1109/ISPCS.2011.6070144
Cheng Pang, Jeffrey Yan, V. Vyatkin, S. Jennings
This paper proposes a method of time-driven control with high-precision synchronous clocks in distributed control systems built following the IEC 61499 standard. It investigates the impact of applying time-driven control on performance of material handling systems. A time-driven control system for a multi-diverter conveyor line has been developed using IEC 61499 Function Blocks architecture with support of the IEEE 1588 Precision Time Protocol. Analytic performance model has been developed and comparisons between the time-driven and two other possible control designs have been conducted and elaborated in terms of costs, logic design, and system throughput.
{"title":"Distributed IEC 61499 material handling control based on time synchronization with IEEE 1588","authors":"Cheng Pang, Jeffrey Yan, V. Vyatkin, S. Jennings","doi":"10.1109/ISPCS.2011.6070144","DOIUrl":"https://doi.org/10.1109/ISPCS.2011.6070144","url":null,"abstract":"This paper proposes a method of time-driven control with high-precision synchronous clocks in distributed control systems built following the IEC 61499 standard. It investigates the impact of applying time-driven control on performance of material handling systems. A time-driven control system for a multi-diverter conveyor line has been developed using IEC 61499 Function Blocks architecture with support of the IEEE 1588 Precision Time Protocol. Analytic performance model has been developed and comparisons between the time-driven and two other possible control designs have been conducted and elaborated in terms of costs, logic design, and system throughput.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127671696","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 : 2011-11-07DOI: 10.1109/ISPCS.2011.6070155
M. Cohn
Ethernet and IEEE 1588 are continuing to emerge in a wide range of industries. Increasingly, they are replacing industry-specific interconnects, delivering performance and cost efficiencies. Initiatives including Industrial Ethernet, IEC 61850, and LXI are all adopting commercial off- the-shelf technologies to achieve broader communications at far lower costs. However, significant investments that are warranted for large automation systems become prohibitively expensive for a diverse set of less, ambitious Quasi-Real-Time (QRT) applications that also require distributed communications and timing. This paper proposes an approach to address the communications and timing/synchronization requirements for QRT systems, characterized by simple and low-cost devices interconnected and synchronized over a real-time network. To achieve the aggressive cost targets, a highly integrated attachment device is introduced that integrates Ethernet communications, IEEE 1588v2 distributed synchronization, and precision I/O for local synchronization in a single, energy efficient device. Systems issues are also raised affecting the applicability for applications that can exploit a QRT network.
{"title":"Timing and synchronization for Quasi-Real-Time systems using IEEE 1588v2 over Ethernet","authors":"M. Cohn","doi":"10.1109/ISPCS.2011.6070155","DOIUrl":"https://doi.org/10.1109/ISPCS.2011.6070155","url":null,"abstract":"Ethernet and IEEE 1588 are continuing to emerge in a wide range of industries. Increasingly, they are replacing industry-specific interconnects, delivering performance and cost efficiencies. Initiatives including Industrial Ethernet, IEC 61850, and LXI are all adopting commercial off- the-shelf technologies to achieve broader communications at far lower costs. However, significant investments that are warranted for large automation systems become prohibitively expensive for a diverse set of less, ambitious Quasi-Real-Time (QRT) applications that also require distributed communications and timing. This paper proposes an approach to address the communications and timing/synchronization requirements for QRT systems, characterized by simple and low-cost devices interconnected and synchronized over a real-time network. To achieve the aggressive cost targets, a highly integrated attachment device is introduced that integrates Ethernet communications, IEEE 1588v2 distributed synchronization, and precision I/O for local synchronization in a single, energy efficient device. Systems issues are also raised affecting the applicability for applications that can exploit a QRT network.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126228876","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 : 2011-11-07DOI: 10.1109/ISPCS.2011.6070160
L. Cosart
The IEEE 1588 packet probe has proved to be an effective tool for the measurement and analysis of network packet delay variation and latency. As more and more IEEE 1588 equipment is designed and deployed in the service of telecommunications networks and for other applications, in some cases with on-path support provided by boundary or transparent clocks, it has become important to be able to characterize this equipment. In many cases the packets themselves are the only timing signal available for study. Thus the packet probe is an essential tool for characterizing this equipment. Likewise, the same metrics developed for the analysis of network packet delay variation can be employed for equipment characterization. This paper, drawing on measurements of commercial equipment, describes how a packet probe along with traditional stability metrics and recently developed packet metrics can be used to characterize IEEE 1588 grandmaster clocks, boundary clocks, and transparent clocks.
{"title":"Characterizing grandmaster, transparent, and boundary clocks with a precision packet probe and packet metrics","authors":"L. Cosart","doi":"10.1109/ISPCS.2011.6070160","DOIUrl":"https://doi.org/10.1109/ISPCS.2011.6070160","url":null,"abstract":"The IEEE 1588 packet probe has proved to be an effective tool for the measurement and analysis of network packet delay variation and latency. As more and more IEEE 1588 equipment is designed and deployed in the service of telecommunications networks and for other applications, in some cases with on-path support provided by boundary or transparent clocks, it has become important to be able to characterize this equipment. In many cases the packets themselves are the only timing signal available for study. Thus the packet probe is an essential tool for characterizing this equipment. Likewise, the same metrics developed for the analysis of network packet delay variation can be employed for equipment characterization. This paper, drawing on measurements of commercial equipment, describes how a packet probe along with traditional stability metrics and recently developed packet metrics can be used to characterize IEEE 1588 grandmaster clocks, boundary clocks, and transparent clocks.","PeriodicalId":416451,"journal":{"name":"2011 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication","volume":"71 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131911114","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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