Localization is a highly important topic in wireless sensor networks as well as in many Internet of Things applications. Many current localization algorithms are based on the Sequential Monte Carlo Localization method (MCL), the accuracy of which is bounded by the radio range. High computational complexity in the sampling step is another issue of these approaches. We present Tri-MCL which significantly improves on the accuracy of the Monte Carlo Localization algorithm. To do this, we leverage three different distance measurement algorithms based on range-free approaches. Using these, we estimate the distances between unknown nodes and anchor nodes to perform more fine-grained filtering of the particles as well as for weighting the particles in the final estimation step of the algorithm. Simulation results illustrate that the proposed algorithm achieves better accuracy than the MCL and SA-MCL algorithms. Furthermore, it also exhibits high efficiency in the sampling step.
{"title":"Tri-MCL: Synergistic Localization for Mobile Ad-Hoc and Wireless Sensor Networks","authors":"Arne Bochem, Yali Yuan, D. Hogrefe","doi":"10.1109/LCN.2016.61","DOIUrl":"https://doi.org/10.1109/LCN.2016.61","url":null,"abstract":"Localization is a highly important topic in wireless sensor networks as well as in many Internet of Things applications. Many current localization algorithms are based on the Sequential Monte Carlo Localization method (MCL), the accuracy of which is bounded by the radio range. High computational complexity in the sampling step is another issue of these approaches. We present Tri-MCL which significantly improves on the accuracy of the Monte Carlo Localization algorithm. To do this, we leverage three different distance measurement algorithms based on range-free approaches. Using these, we estimate the distances between unknown nodes and anchor nodes to perform more fine-grained filtering of the particles as well as for weighting the particles in the final estimation step of the algorithm. Simulation results illustrate that the proposed algorithm achieves better accuracy than the MCL and SA-MCL algorithms. Furthermore, it also exhibits high efficiency in the sampling step.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"58 1","pages":"333-338"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82018297","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}
Chun-Hao Liao, Yuki Katsumata, Makoto Suzuki, H. Morikawa
Many works attributed the successful reception of concurrent transmission (CT) to the constructive interference. However, due to the inevitable carrier frequency offset (CFO) and the resulted beating effect, the claim of constructive interference is actually not valid. To clarify the reason behind the successful receptions under CT, we conduct extensive evaluations and identify the following findings. 1) We show that the IEEE 802.15.4 receivers survive the beating effect mainly because of the direct sequence spread spectrum (DSSS), while systems without the protection of DSSS are not applicable to CT. 2) We identify a counterintuitive phenomenon that the IEEE 802.15.4 receiver could survive only the beating results from large CFO, while performing poorly when CFO is small. 3) We demonstrate that, even if the receivers survive, CT links lead to little performance improvements compared to conventional signal transmission links from the SNR point of view.
{"title":"Revisiting the So-Called Constructive Interference in Concurrent Transmission","authors":"Chun-Hao Liao, Yuki Katsumata, Makoto Suzuki, H. Morikawa","doi":"10.1109/LCN.2016.56","DOIUrl":"https://doi.org/10.1109/LCN.2016.56","url":null,"abstract":"Many works attributed the successful reception of concurrent transmission (CT) to the constructive interference. However, due to the inevitable carrier frequency offset (CFO) and the resulted beating effect, the claim of constructive interference is actually not valid. To clarify the reason behind the successful receptions under CT, we conduct extensive evaluations and identify the following findings. 1) We show that the IEEE 802.15.4 receivers survive the beating effect mainly because of the direct sequence spread spectrum (DSSS), while systems without the protection of DSSS are not applicable to CT. 2) We identify a counterintuitive phenomenon that the IEEE 802.15.4 receiver could survive only the beating results from large CFO, while performing poorly when CFO is small. 3) We demonstrate that, even if the receivers survive, CT links lead to little performance improvements compared to conventional signal transmission links from the SNR point of view.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"58 1","pages":"280-288"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87659272","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}
Present data center (DC) network provisioning schemes primarily utilize conventional load-balancing technologies, offering individual application performance improvement. Diversity in application usage however, makes isolated application prioritization a performance caveat for users with varying application trends. The present paper proposes a user profiling approach to capture application trends based on generic flow measurements (NetFlow) and employs the extracted profiles to create DC traffic forwarding policies. The scheme allows operators to define a global profile and application hierarchy based on extracted profiles to prioritize traffic for individual user classes. The proposed design was tested by extracting user profiles from a realistic enterprise network, and further simulated to dynamically manage DC traffic using the software defined networking paradigm. Compared to conventional traffic management schemes, the frame delivery ratio and effective throughput of our design was significantly higher for high priority north-south user traffic as well as the inter-server east-west application traffic.
{"title":"User-Centric Network Provisioning in Software Defined Data Center Environment","authors":"Taimur Bakhshi, B. Ghita","doi":"10.1109/LCN.2016.57","DOIUrl":"https://doi.org/10.1109/LCN.2016.57","url":null,"abstract":"Present data center (DC) network provisioning schemes primarily utilize conventional load-balancing technologies, offering individual application performance improvement. Diversity in application usage however, makes isolated application prioritization a performance caveat for users with varying application trends. The present paper proposes a user profiling approach to capture application trends based on generic flow measurements (NetFlow) and employs the extracted profiles to create DC traffic forwarding policies. The scheme allows operators to define a global profile and application hierarchy based on extracted profiles to prioritize traffic for individual user classes. The proposed design was tested by extracting user profiles from a realistic enterprise network, and further simulated to dynamically manage DC traffic using the software defined networking paradigm. Compared to conventional traffic management schemes, the frame delivery ratio and effective throughput of our design was significantly higher for high priority north-south user traffic as well as the inter-server east-west application traffic.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"225 1","pages":"289-297"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85258809","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 control of excessive downloads by rogue users in organizational LANs is the subject of this work. Two mechanisms have been used in order to accomplish this. The first mechanism, is TCP rate control (TCR), it is a receiver-based flow control technique that can be used to effectively rate limit rogue users' flows, making more bandwidth available to regular users. The second mechanism, admission control reduces the bandwidth wastage due to users disconnecting out of impatience when user goodputs are low. Using simulation-based experiments, it has been demonstrated that the composite technique, exclusive TCP rate and admission control (xTRAC) provides seamless control of rogue users, while improving response times and goodput by upto 58% during overload. In this way regular users are incentivized and rogue users are penalized leading to long-term control of users.
{"title":"Organization-Level Control of Excessive Internet Downloads","authors":"Saad Y. Sait, H. Murthy, K. Sivalingam","doi":"10.1109/LCN.2016.38","DOIUrl":"https://doi.org/10.1109/LCN.2016.38","url":null,"abstract":"The control of excessive downloads by rogue users in organizational LANs is the subject of this work. Two mechanisms have been used in order to accomplish this. The first mechanism, is TCP rate control (TCR), it is a receiver-based flow control technique that can be used to effectively rate limit rogue users' flows, making more bandwidth available to regular users. The second mechanism, admission control reduces the bandwidth wastage due to users disconnecting out of impatience when user goodputs are low. Using simulation-based experiments, it has been demonstrated that the composite technique, exclusive TCP rate and admission control (xTRAC) provides seamless control of rogue users, while improving response times and goodput by upto 58% during overload. In this way regular users are incentivized and rogue users are penalized leading to long-term control of users.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"34 1","pages":"184-187"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91242585","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}
Despite the improvements brought about by content-centric networking's (CCN) in-network caching and interest aggregation, congestion can still take place in such networks due to the dominance of non-reusable content, high cache churn, high delay variations, premature timeouts and interest retransmission. This becomes even more dramatic when multi-path routing is adopted. Identifying that at a given node in CCN, the Pending Interest Table (PIT) occupancy can give a good estimate of the data workload to arrive to the node in the near future, we propose in this paper a novel mechanism to control congestion in CCN based on this idea. Our mechanism uses the average occupancy of the PIT to estimate the anticipated data packet transmission queue length and sends explicit congestion notification signals to the content requesters to reduce their interest sending rates when such anticipated queue size exceeds a threshold. We demonstrate the effectiveness of our proposed mechanism via ns-3 simulation.
{"title":"Inferring and Controlling Congestion in CCN via the Pending Interest Table Occupancy","authors":"Amuda James Abu, B. Bensaou, A. Abdelmoniem","doi":"10.1109/LCN.2016.72","DOIUrl":"https://doi.org/10.1109/LCN.2016.72","url":null,"abstract":"Despite the improvements brought about by content-centric networking's (CCN) in-network caching and interest aggregation, congestion can still take place in such networks due to the dominance of non-reusable content, high cache churn, high delay variations, premature timeouts and interest retransmission. This becomes even more dramatic when multi-path routing is adopted. Identifying that at a given node in CCN, the Pending Interest Table (PIT) occupancy can give a good estimate of the data workload to arrive to the node in the near future, we propose in this paper a novel mechanism to control congestion in CCN based on this idea. Our mechanism uses the average occupancy of the PIT to estimate the anticipated data packet transmission queue length and sends explicit congestion notification signals to the content requesters to reduce their interest sending rates when such anticipated queue size exceeds a threshold. We demonstrate the effectiveness of our proposed mechanism via ns-3 simulation.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"12 1","pages":"433-441"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81737747","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}
L. M. Silveira, Robert M. Oliveira, Moises Vidal Ribeiro, L. Vieira, M. Vieira, A. Vieira
Power line communication systems face several challenges which degrade data communication quality. To overcome such issues, we propose CodePLC, a network coding Power Line Communication MAC protocol. We use a single relay node to intermediate communication, storing, and forwarding linear combinations of data packets. We evaluate CodePLC performance through simulations of a common topology for a PLC system under a wide range of scenarios. In sum, our results show that in a broadcast like transmission, the use of network coding enhances overall system performance. When compared to a traditional PLC system, we have observed an average of 115% goodput increase. Moreover, our protocol reduces in 112% the average of network occupancy buffers. Finally, CodePLC reduces mean latency by four times.
{"title":"CodePLC: A Network Coding MAC Protocol for Power Line Communication","authors":"L. M. Silveira, Robert M. Oliveira, Moises Vidal Ribeiro, L. Vieira, M. Vieira, A. Vieira","doi":"10.1109/LCN.2016.112","DOIUrl":"https://doi.org/10.1109/LCN.2016.112","url":null,"abstract":"Power line communication systems face several challenges which degrade data communication quality. To overcome such issues, we propose CodePLC, a network coding Power Line Communication MAC protocol. We use a single relay node to intermediate communication, storing, and forwarding linear combinations of data packets. We evaluate CodePLC performance through simulations of a common topology for a PLC system under a wide range of scenarios. In sum, our results show that in a broadcast like transmission, the use of network coding enhances overall system performance. When compared to a traditional PLC system, we have observed an average of 115% goodput increase. Moreover, our protocol reduces in 112% the average of network occupancy buffers. Finally, CodePLC reduces mean latency by four times.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"20 1","pages":"643-646"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84022396","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}
M. Rathore, Anand Paul, Awais Ahmad, M. Imran, M. Guizani
Internet service providers (ISPs) and telecommunication authorities are interested in detecting VoIP calls either to block illegal commercial VoIP or prioritize the paid users VoIP calls. Signature-based, port-based, and pattern-based VoIP detection techniques are not more accurate and not efficient due to complex security and tunneling mechanisms used by VoIP. Therefore, in this paper, we propose a rule-based generic, robust, and efficient statistical analysis-based solution to identify encrypted, non-encrypted, or tunneled VoIP media (voice) flows using threshold approach. In addition, a system is proposed to efficiently process high-speed real-time network traffic. The accuracy and efficiency evaluation results and the comparative study show that the proposed system outperforms the existing systems with the ability to work in real-time and high-speed Big Data environment.
{"title":"High-Speed Network Traffic Analysis: Detecting VoIP Calls in Secure Big Data Streaming","authors":"M. Rathore, Anand Paul, Awais Ahmad, M. Imran, M. Guizani","doi":"10.1109/LCN.2016.128","DOIUrl":"https://doi.org/10.1109/LCN.2016.128","url":null,"abstract":"Internet service providers (ISPs) and telecommunication authorities are interested in detecting VoIP calls either to block illegal commercial VoIP or prioritize the paid users VoIP calls. Signature-based, port-based, and pattern-based VoIP detection techniques are not more accurate and not efficient due to complex security and tunneling mechanisms used by VoIP. Therefore, in this paper, we propose a rule-based generic, robust, and efficient statistical analysis-based solution to identify encrypted, non-encrypted, or tunneled VoIP media (voice) flows using threshold approach. In addition, a system is proposed to efficiently process high-speed real-time network traffic. The accuracy and efficiency evaluation results and the comparative study show that the proposed system outperforms the existing systems with the ability to work in real-time and high-speed Big Data environment.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"6 1","pages":"595-598"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85852089","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 the Public Key infrastructure (PKI) model, digital certificates play a vital role in securing online communication. Communicating parties exchange and validate these certificates, the validation fails if a certificate has been revoked. In this paper we propose the Certificate Revocation Guard (CRG) to efficiently check certificate revocation while minimising bandwidth, latency and storage overheads. CRG is based on OCSP, which caches the status of certificates locally. CRG could be installed on the user's machine, at the organisational proxy or even at the ISP level. Compared to a naive approach (where a client checks the revocation status of all certificates in the chain on every request), CRG decreases the bandwidth overheads and network latencies by 95%. Using CRG incurs 69% lower storage overheads compared to the CRL method. Our results demonstrate the effectiveness of our approach to improve certificate revocation.
{"title":"Certificate Revocation Guard (CRG): An Efficient Mechanism for Checking Certificate Revocation","authors":"Qinwen Hu, M. R. Asghar, N. Brownlee","doi":"10.1109/LCN.2016.84","DOIUrl":"https://doi.org/10.1109/LCN.2016.84","url":null,"abstract":"In the Public Key infrastructure (PKI) model, digital certificates play a vital role in securing online communication. Communicating parties exchange and validate these certificates, the validation fails if a certificate has been revoked. In this paper we propose the Certificate Revocation Guard (CRG) to efficiently check certificate revocation while minimising bandwidth, latency and storage overheads. CRG is based on OCSP, which caches the status of certificates locally. CRG could be installed on the user's machine, at the organisational proxy or even at the ISP level. Compared to a naive approach (where a client checks the revocation status of all certificates in the chain on every request), CRG decreases the bandwidth overheads and network latencies by 95%. Using CRG incurs 69% lower storage overheads compared to the CRL method. Our results demonstrate the effectiveness of our approach to improve certificate revocation.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"139 1","pages":"527-530"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85887796","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}
David C. Harrison, Winston K.G. Seah, Hang Yu, R. Rayudu
Wireless sensor networks for rarely occurring critical events must maintain sensing coverage and low latency network connectivity to ensure event detection and subsequent rapid propagation of notification messages. Existing geographic forwarding algorithms have proved successful in providing energy efficient network connectivity for arbitrary topologies where sensing coverage is not guaranteed. This paper proposes a location aware algorithm for Swift Opportunistic Forwarding of Infrequent Events (SOFIE) that takes advantage of geometric properties common to sensing networks providing perfect area coverage. The algorithm is shown to deliver more rapid message propagation than two established, general purpose geographic forwarding algorithm in optimally and randomly placed networks of varied sensing node density. Further, the algorithm is shown to maintain this advantage when deployed in a coverage preserving, duty-cycled sensing network where nodes may power down whilst the network is actively forwarding event notification messages.
{"title":"Opportunistic Geographic Forwarding in Wireless Sensor Networks for Critical Rare Events","authors":"David C. Harrison, Winston K.G. Seah, Hang Yu, R. Rayudu","doi":"10.1109/LCN.2016.46","DOIUrl":"https://doi.org/10.1109/LCN.2016.46","url":null,"abstract":"Wireless sensor networks for rarely occurring critical events must maintain sensing coverage and low latency network connectivity to ensure event detection and subsequent rapid propagation of notification messages. Existing geographic forwarding algorithms have proved successful in providing energy efficient network connectivity for arbitrary topologies where sensing coverage is not guaranteed. This paper proposes a location aware algorithm for Swift Opportunistic Forwarding of Infrequent Events (SOFIE) that takes advantage of geometric properties common to sensing networks providing perfect area coverage. The algorithm is shown to deliver more rapid message propagation than two established, general purpose geographic forwarding algorithm in optimally and randomly placed networks of varied sensing node density. Further, the algorithm is shown to maintain this advantage when deployed in a coverage preserving, duty-cycled sensing network where nodes may power down whilst the network is actively forwarding event notification messages.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"18 1","pages":"216-219"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89388497","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 the past, several proposals to support fast handover in wireless mesh networks have been published. However, most handover extensions are only concerned with moving stations that are unaware of the used routing protocol and assume relatively stationary routing nodes. In this paper we propose an extension to the BATMAN routing protocol to support seamless handover of routing nodes in infrastructure wireless mesh networks. We implement the new extension in our wireless mesh testbed and evaluate its performance in comparison to a standard WLAN handover followed by a route reestablishment using BATMAN. The evaluation shows that route reestablishment is more than 40 times faster with our extension when compared to standard BATMAN.
{"title":"B. A. T. M. A. N. Handover Extension for Routing Nodes in Infrastructure WMNs","authors":"Patrick Herrmann, Ulrike Meyer","doi":"10.1109/LCN.2016.118","DOIUrl":"https://doi.org/10.1109/LCN.2016.118","url":null,"abstract":"In the past, several proposals to support fast handover in wireless mesh networks have been published. However, most handover extensions are only concerned with moving stations that are unaware of the used routing protocol and assume relatively stationary routing nodes. In this paper we propose an extension to the BATMAN routing protocol to support seamless handover of routing nodes in infrastructure wireless mesh networks. We implement the new extension in our wireless mesh testbed and evaluate its performance in comparison to a standard WLAN handover followed by a route reestablishment using BATMAN. The evaluation shows that route reestablishment is more than 40 times faster with our extension when compared to standard BATMAN.","PeriodicalId":6864,"journal":{"name":"2016 IEEE 41st Conference on Local Computer Networks (LCN)","volume":"34 1","pages":"680-687"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86483774","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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