Pub Date : 2015-08-13DOI: 10.1109/EuCNC.2015.7194123
Seyed Ehsan Ghoreishi, H. Aghvami, Hadi Saki
Reducing the queue length and queuing delay in the buffer which in turn reduces congestion and latency in the network are of great importance for real-time video services. This paper proposes a congestion avoidance active queue management, tailored for scalable video coding (SVC). This distortion-constrained (DC) queue management mechanism maximally decreases the queue length and queuing delay of video traffic for a given maximum allowable distortion in each video. DC prioritizes video layers in accordance with their hierarchical layer structure into multiple virtual queues inside the buffer. Losses in different layers of the hierarchy introduce different amounts of reduction in PSNR. Therefore, we determine the optimal drop rate in each virtual queue which causes minimal distortion to the stream while achieving a maximal drop rate. This in turn produces the highest reduction in the average buffer queue length and queuing delay for a given distortion. Compared with the widely deployed tail drop mechanism, our proposed scheme would increase the fraction of QoS-satisfied users and maintain a considerably shorter queue length in the buffer which would combat congestion and decrease queuing delay.
{"title":"Active queue management for congestion avoidance in multimedia streaming","authors":"Seyed Ehsan Ghoreishi, H. Aghvami, Hadi Saki","doi":"10.1109/EuCNC.2015.7194123","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194123","url":null,"abstract":"Reducing the queue length and queuing delay in the buffer which in turn reduces congestion and latency in the network are of great importance for real-time video services. This paper proposes a congestion avoidance active queue management, tailored for scalable video coding (SVC). This distortion-constrained (DC) queue management mechanism maximally decreases the queue length and queuing delay of video traffic for a given maximum allowable distortion in each video. DC prioritizes video layers in accordance with their hierarchical layer structure into multiple virtual queues inside the buffer. Losses in different layers of the hierarchy introduce different amounts of reduction in PSNR. Therefore, we determine the optimal drop rate in each virtual queue which causes minimal distortion to the stream while achieving a maximal drop rate. This in turn produces the highest reduction in the average buffer queue length and queuing delay for a given distortion. Compared with the widely deployed tail drop mechanism, our proposed scheme would increase the fraction of QoS-satisfied users and maintain a considerably shorter queue length in the buffer which would combat congestion and decrease queuing delay.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128064151","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 : 2015-08-13DOI: 10.1109/EuCNC.2015.7194030
S. Dimitrov, N. Privitera, R. Suffritti, G. Boccolini, A. Awoseyila, B. Evans
In this paper, we study the applicability of terrestrial mobile waveforms in the return link of a high throughput satellite (HTS) communication system. These include orthogonal frequency division multiple access (OFDMA), single-carrier frequency division multiple access (SC-FDMA) and filter bank multi-carrier (FBMC). Key solutions to the challenges in a geostationary orbit (GEO) satellite channel, such as synchronization and non-linear distortion, are presented. A global-positioning-system-(GPS)-based approach for synchronization acquisition is proposed, while suitable algorithms are studied for timing/frequency offset estimation and synchronization tracking. The spectral and power efficiencies of the schemes are optimized by means of an intermodulation interference (IMI) cancelling receiver, and these are compared to state-of-the-art time division multiple access (TDMA). Finally, end-to-end simulations validate the system performance.
{"title":"Spectrally efficient waveforms for the return link in satellite communication systems","authors":"S. Dimitrov, N. Privitera, R. Suffritti, G. Boccolini, A. Awoseyila, B. Evans","doi":"10.1109/EuCNC.2015.7194030","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194030","url":null,"abstract":"In this paper, we study the applicability of terrestrial mobile waveforms in the return link of a high throughput satellite (HTS) communication system. These include orthogonal frequency division multiple access (OFDMA), single-carrier frequency division multiple access (SC-FDMA) and filter bank multi-carrier (FBMC). Key solutions to the challenges in a geostationary orbit (GEO) satellite channel, such as synchronization and non-linear distortion, are presented. A global-positioning-system-(GPS)-based approach for synchronization acquisition is proposed, while suitable algorithms are studied for timing/frequency offset estimation and synchronization tracking. The spectral and power efficiencies of the schemes are optimized by means of an intermodulation interference (IMI) cancelling receiver, and these are compared to state-of-the-art time division multiple access (TDMA). Finally, end-to-end simulations validate the system performance.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133291370","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 : 2015-08-13DOI: 10.1109/EuCNC.2015.7194064
Sergio Cicalò, V. Tralli
Resource allocators that maximize ergodic sum-rate under proportional rate constraints have been recently introduced and analysed for both OFDMA and SC-FDMA wireless systems. They are able to provide long-term fairness by assigning to users, on average, a predefined share of the available system capacity. However, the short-term fairness of these schedulers with its effect on the delays, and their efficiency in presence of bursty traffic may be open issues for a possible application in 4G wireless networks. In this paper we address these issues by proposing some solutions that make such resource allocators able to support both GBR and best effort traffic. We consider the uplink of a LTE single cell scenario with some realistic conditions (e.g., discrete rate assignment, power control) and evaluate the performance of the proposed solutions in presence of heterogeneous traffic by using QoS-aware proportional fairness based schedulers as benchmark. The results show that the proposed resource allocator is able to achieve an high number of satisfied GBR users with a significant reduction of the packet delay without starving non-GBR users.
{"title":"Fair resource allocation with QoS support for the uplink of LTE systems","authors":"Sergio Cicalò, V. Tralli","doi":"10.1109/EuCNC.2015.7194064","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194064","url":null,"abstract":"Resource allocators that maximize ergodic sum-rate under proportional rate constraints have been recently introduced and analysed for both OFDMA and SC-FDMA wireless systems. They are able to provide long-term fairness by assigning to users, on average, a predefined share of the available system capacity. However, the short-term fairness of these schedulers with its effect on the delays, and their efficiency in presence of bursty traffic may be open issues for a possible application in 4G wireless networks. In this paper we address these issues by proposing some solutions that make such resource allocators able to support both GBR and best effort traffic. We consider the uplink of a LTE single cell scenario with some realistic conditions (e.g., discrete rate assignment, power control) and evaluate the performance of the proposed solutions in presence of heterogeneous traffic by using QoS-aware proportional fairness based schedulers as benchmark. The results show that the proposed resource allocator is able to achieve an high number of satisfied GBR users with a significant reduction of the packet delay without starving non-GBR users.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114822885","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 : 2015-08-13DOI: 10.1109/EuCNC.2015.7194104
E. Pateromichelakis, Andreas Mäder, A. Domenico, R. Fritzsche, Paul de Kerret, J. Bartelt
This paper provides an overview of joint radio access network (RAN) and backhaul (BH) optimization methods in dense small cell networks, assuming a heterogeneous backhaul and centralization by Cloud RAN. The main focus is on the design of novel MAC (medium access control) and RRM (radio resource management) schemes for constrained, non-ideal backhaul which can influence the RAN performance. In this context, we provide some key technology approaches which incorporate the RAN/BH awareness at the cloud and exploit the benefits of Cloud-RAN by dynamically adapting to BH constraints.
{"title":"Joint RAN/backhaul optimization in centralized 5G RAN","authors":"E. Pateromichelakis, Andreas Mäder, A. Domenico, R. Fritzsche, Paul de Kerret, J. Bartelt","doi":"10.1109/EuCNC.2015.7194104","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194104","url":null,"abstract":"This paper provides an overview of joint radio access network (RAN) and backhaul (BH) optimization methods in dense small cell networks, assuming a heterogeneous backhaul and centralization by Cloud RAN. The main focus is on the design of novel MAC (medium access control) and RRM (radio resource management) schemes for constrained, non-ideal backhaul which can influence the RAN performance. In this context, we provide some key technology approaches which incorporate the RAN/BH awareness at the cloud and exploit the benefits of Cloud-RAN by dynamically adapting to BH constraints.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124846522","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 : 2015-08-13DOI: 10.1109/EuCNC.2015.7194039
Marc Torrellas, A. Agustin, J. Vidal
The net degrees of freedom (DoF) describe the efficiency of a protocol in terms of network throughput at high signal-to-noise ratio (SNR). As the conventional DoF, it captures how the achievable user data rate grows as SNR increases, but also takes into account the limited channel state information at the transmitters (CSIT), and required protocol overheads. This work studies the impact of short channel coherence time for the K-user Multiple-Input Single-Output (MISO) Interference Channel (IC) by means of the net DoF. We propose different protocols, combining techniques that exploit different levels of CSIT (delayed, current or no CSIT), and elucidating which performs better as a function of user mobility.
{"title":"Net DoF analysis for the K-user MISO IC with outdated and imperfect channel feedback","authors":"Marc Torrellas, A. Agustin, J. Vidal","doi":"10.1109/EuCNC.2015.7194039","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194039","url":null,"abstract":"The net degrees of freedom (DoF) describe the efficiency of a protocol in terms of network throughput at high signal-to-noise ratio (SNR). As the conventional DoF, it captures how the achievable user data rate grows as SNR increases, but also takes into account the limited channel state information at the transmitters (CSIT), and required protocol overheads. This work studies the impact of short channel coherence time for the K-user Multiple-Input Single-Output (MISO) Interference Channel (IC) by means of the net DoF. We propose different protocols, combining techniques that exploit different levels of CSIT (delayed, current or no CSIT), and elucidating which performs better as a function of user mobility.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122182346","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 : 2015-08-13DOI: 10.1109/EuCNC.2015.7194105
H. Einsiedler, A. Gavras, Patrick Sellstedt, R. Aguiar, R. Trivisonno, D. Lavaux
This paper presents high level design concepts for the control plane (C-plane) of the upcoming 5G networks, in the framework of Fixed-Mobile Convergence (FMC). This control plane is enabled by SDN and NFV technologies in order to offer a very flexible environment able to optimally deploy network infrastructure(s) that will cope with multiple service provisions scenarios. Furthermore, our innovative control plane will be able to support fast deployment of novel services depending on the requirements from different use case and application scenarios and enabling the operators to provide fast answers to the society challenges ahead.
{"title":"System design for 5G converged networks","authors":"H. Einsiedler, A. Gavras, Patrick Sellstedt, R. Aguiar, R. Trivisonno, D. Lavaux","doi":"10.1109/EuCNC.2015.7194105","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194105","url":null,"abstract":"This paper presents high level design concepts for the control plane (C-plane) of the upcoming 5G networks, in the framework of Fixed-Mobile Convergence (FMC). This control plane is enabled by SDN and NFV technologies in order to offer a very flexible environment able to optimally deploy network infrastructure(s) that will cope with multiple service provisions scenarios. Furthermore, our innovative control plane will be able to support fast deployment of novel services depending on the requirements from different use case and application scenarios and enabling the operators to provide fast answers to the society challenges ahead.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"64 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116316674","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 : 2015-08-13DOI: 10.1109/EuCNC.2015.7194049
Iman Tavakkolnia, M. Safari
Using the inverse scattering method known for solving partial differential equations such as nonlinear Schrödinger equation, we analyse a fibre optic communication system which maps data on both discrete and continuous spectra defined by nonlinear Fourier transform. By signalling over both spectra, the degrees of freedom of the channel can be exploited to potentially increase the achievable data-rate in an attempt to approach the capacity of the optical fiber. Considering such a system, our results demonstrate the signal-dependency of the noise mapped to the nonlinear frequency domain. The temporal broadening factor is also studied for different pulse shapes and pulse sequence lengths modulated over the continuous spectrum. Finally, the error rate performance of the communication system signalling over both discrete and continuous spectra is presented.
{"title":"Signalling over nonlinear fibre-optic channels by utilizing both solitonic and radiative spectra","authors":"Iman Tavakkolnia, M. Safari","doi":"10.1109/EuCNC.2015.7194049","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194049","url":null,"abstract":"Using the inverse scattering method known for solving partial differential equations such as nonlinear Schrödinger equation, we analyse a fibre optic communication system which maps data on both discrete and continuous spectra defined by nonlinear Fourier transform. By signalling over both spectra, the degrees of freedom of the channel can be exploited to potentially increase the achievable data-rate in an attempt to approach the capacity of the optical fiber. Considering such a system, our results demonstrate the signal-dependency of the noise mapped to the nonlinear frequency domain. The temporal broadening factor is also studied for different pulse shapes and pulse sequence lengths modulated over the continuous spectrum. Finally, the error rate performance of the communication system signalling over both discrete and continuous spectra is presented.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"81 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128133759","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 : 2015-08-13DOI: 10.1109/EuCNC.2015.7194117
Vincent Autefage, S. Chaumette, D. Magoni
Time drift in distributed systems is an important issue especially for mobile ad hoc networks. Indeed, it can break the synchronization between the internal clocks of the nodes. Consequently, protocols over such networks should consider this problem in the case where they need to use time information. In this paper, we define a new collaborative system for autonomous mobile robots called AMiRALE. We present three versions of this system each with different time constraints. We provide its theoretical description as well as simulation results according to a park cleaning scenario. Results show that time synchronization has a limited impact on the efficiency of our collaborative system.
{"title":"Comparison of time synchronization techniques in a distributed collaborative swarm system","authors":"Vincent Autefage, S. Chaumette, D. Magoni","doi":"10.1109/EuCNC.2015.7194117","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194117","url":null,"abstract":"Time drift in distributed systems is an important issue especially for mobile ad hoc networks. Indeed, it can break the synchronization between the internal clocks of the nodes. Consequently, protocols over such networks should consider this problem in the case where they need to use time information. In this paper, we define a new collaborative system for autonomous mobile robots called AMiRALE. We present three versions of this system each with different time constraints. We provide its theoretical description as well as simulation results according to a park cleaning scenario. Results show that time synchronization has a limited impact on the efficiency of our collaborative system.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132996341","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 : 2015-08-13DOI: 10.1109/EuCNC.2015.7194120
P. Casas, P. Fiadino, M. Schiavone
The popularity of Online Social Networks (OSNs) has created an immense amount of research for the analysis of these networks and the traffic produced by popular applications such as Facebook. In this paper we study the networking characteristics of OSNs in mobile networks, analyzing the most popular OSNs in western countries: Facebook and WhatsApp. By analyzing two large-scale traffic traces collected at the cellular network of a major European ISP, we characterize and compare the networking behavior of Facebook and WhatsApp, considering not only the traffic flows but also the network infrastructures hosting them. To enable a better understanding of the Quality of Experience (QoE) requirements of these two applications in the mobile context, we present the results of a subjective QoE study of both Facebook and WhatsApp in smartphones. Our study serves the main purpose of better understanding how major OSNs are provisioned in today's mobile networks, paying special attention to their QoE characteristics. To the best of our knowledge, this is the first paper providing such an analysis using large-scale measurements in cellular networks and subjective QoE tests in smartphones.
{"title":"QoMOSN - On the analysis of traffic and Quality of Experience in Mobile Online Social Networks","authors":"P. Casas, P. Fiadino, M. Schiavone","doi":"10.1109/EuCNC.2015.7194120","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194120","url":null,"abstract":"The popularity of Online Social Networks (OSNs) has created an immense amount of research for the analysis of these networks and the traffic produced by popular applications such as Facebook. In this paper we study the networking characteristics of OSNs in mobile networks, analyzing the most popular OSNs in western countries: Facebook and WhatsApp. By analyzing two large-scale traffic traces collected at the cellular network of a major European ISP, we characterize and compare the networking behavior of Facebook and WhatsApp, considering not only the traffic flows but also the network infrastructures hosting them. To enable a better understanding of the Quality of Experience (QoE) requirements of these two applications in the mobile context, we present the results of a subjective QoE study of both Facebook and WhatsApp in smartphones. Our study serves the main purpose of better understanding how major OSNs are provisioned in today's mobile networks, paying special attention to their QoE characteristics. To the best of our knowledge, this is the first paper providing such an analysis using large-scale measurements in cellular networks and subjective QoE tests in smartphones.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133263753","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 : 2015-08-13DOI: 10.1109/EuCNC.2015.7194042
Sinan Atan, Ümit Aygölü
In this paper, relay networks specialized for two end users with common destination are studied. Both users transmit their signals directly and via relay to destination in Rayleigh fading channels. In this regard, three novel protocols applying automatic repeat request (ARQ) mechanism at relay and/or destination to guarantee successful packet delivery, are proposed for decode-and-forward (DF) strategy at relay. The new protocols designed to achieve high rate, reliability and energy efficiency, are described based on their Markov chain models. Numerical results involving Shannon's outage probability for each channel both in single and multiple access scenarios, are presented to compare these protocols in terms of goodput, reliability, normalized goodput and energy efficiency.
{"title":"Novel protocols for cooperative wireless networks with common destination","authors":"Sinan Atan, Ümit Aygölü","doi":"10.1109/EuCNC.2015.7194042","DOIUrl":"https://doi.org/10.1109/EuCNC.2015.7194042","url":null,"abstract":"In this paper, relay networks specialized for two end users with common destination are studied. Both users transmit their signals directly and via relay to destination in Rayleigh fading channels. In this regard, three novel protocols applying automatic repeat request (ARQ) mechanism at relay and/or destination to guarantee successful packet delivery, are proposed for decode-and-forward (DF) strategy at relay. The new protocols designed to achieve high rate, reliability and energy efficiency, are described based on their Markov chain models. Numerical results involving Shannon's outage probability for each channel both in single and multiple access scenarios, are presented to compare these protocols in terms of goodput, reliability, normalized goodput and energy efficiency.","PeriodicalId":310313,"journal":{"name":"2015 European Conference on Networks and Communications (EuCNC)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123952938","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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