Pub Date : 2021-06-15DOI: 10.1109/MedComNet52149.2021.9501243
C. M. França, R. S. Couto, P. B. Velloso
IoT (Internet of Things) gateways receive data from thousands of sensors and send it to the cloud, which runs intelligent services. However, collected data might have missing or anomalous values due to various reasons, such as network problems, damaged sensors, or security attacks. Missing and noisy data can affect future decision-making, so IoT gateways need to transmit consistent data to the cloud. This work proposes a method to impute missing data on IoT gateways based on neural network regression. We validate this method using six years of weather data from a station located in Rio de Janeiro, considering different percentages of missing data. The results show that the regression models have more than a 0.92 R-squared score and low errors when predicting sensor measurements. Furthermore, we show that the neural network implementation can run on IoT gateways due to its short execution time and low memory utilization. Finally, we show that a single model performs well even when 50% of the data is missing, highlighting the proposed approach's generality.
{"title":"Data imputation on IoT gateways using machine learning","authors":"C. M. França, R. S. Couto, P. B. Velloso","doi":"10.1109/MedComNet52149.2021.9501243","DOIUrl":"https://doi.org/10.1109/MedComNet52149.2021.9501243","url":null,"abstract":"IoT (Internet of Things) gateways receive data from thousands of sensors and send it to the cloud, which runs intelligent services. However, collected data might have missing or anomalous values due to various reasons, such as network problems, damaged sensors, or security attacks. Missing and noisy data can affect future decision-making, so IoT gateways need to transmit consistent data to the cloud. This work proposes a method to impute missing data on IoT gateways based on neural network regression. We validate this method using six years of weather data from a station located in Rio de Janeiro, considering different percentages of missing data. The results show that the regression models have more than a 0.92 R-squared score and low errors when predicting sensor measurements. Furthermore, we show that the neural network implementation can run on IoT gateways due to its short execution time and low memory utilization. Finally, we show that a single model performs well even when 50% of the data is missing, highlighting the proposed approach's generality.","PeriodicalId":272937,"journal":{"name":"2021 19th Mediterranean Communication and Computer Networking Conference (MedComNet)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126924734","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 : 2021-06-15DOI: 10.1109/MedComNet52149.2021.9501244
Mateus Mattos, A. Rodrigues, Rui Meireles, A. Aguiar
To improve range, 802.11ad uses directional communication, the first step of which is to choose the best antenna configuration, or sector. We studied the sector selection behavior of Commercial Off-The-Shelf (COTS) 802.11ad equipment in an experimental Vehicle-to-Infrastructure (V2I) communication scenario. Analysis of the collected data revealed the following inefficiencies: (i) a large number of sector selection attempts that do not result in a sector change; and (ii) a “ping-pong” effect in which a node oscillates between two sectors. With this in mind we studied an alternative antenna sector selection scheme that uses spatially-indexed historical performance data to pick the statistically-best sector for any given geolocation. A trace-based analysis showed that such a strategy can potentially improve throughput by up to 60%, depending on location.
{"title":"Geolocation-based Sector Selection for Vehicle-to-Infrastructure 802.11ad Communication","authors":"Mateus Mattos, A. Rodrigues, Rui Meireles, A. Aguiar","doi":"10.1109/MedComNet52149.2021.9501244","DOIUrl":"https://doi.org/10.1109/MedComNet52149.2021.9501244","url":null,"abstract":"To improve range, 802.11ad uses directional communication, the first step of which is to choose the best antenna configuration, or sector. We studied the sector selection behavior of Commercial Off-The-Shelf (COTS) 802.11ad equipment in an experimental Vehicle-to-Infrastructure (V2I) communication scenario. Analysis of the collected data revealed the following inefficiencies: (i) a large number of sector selection attempts that do not result in a sector change; and (ii) a “ping-pong” effect in which a node oscillates between two sectors. With this in mind we studied an alternative antenna sector selection scheme that uses spatially-indexed historical performance data to pick the statistically-best sector for any given geolocation. A trace-based analysis showed that such a strategy can potentially improve throughput by up to 60%, depending on location.","PeriodicalId":272937,"journal":{"name":"2021 19th Mediterranean Communication and Computer Networking Conference (MedComNet)","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124199870","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 : 2021-06-15DOI: 10.1109/MedComNet52149.2021.9501273
Ion Turcanu, A. Baiocchi, Nikita Lyamin, A. Vinel
Vehicular networking enables a wide range of emerging Cooperative Intelligent Transportation System (C-ITS) applications, from safety to traffic efficiency and infotainment. Many of these applications depend on the reliability and timeliness of status information periodically exchanged among vehicles on the same wireless communication channel. A major effort has been spent, especially by standardization bodies, to define congestion control algorithms for the vehicular networking environment. The picture is, however, more complex than simply controlling the load level on the channel, given the non-trivial interplay of delivery reliability, system throughput, and timeliness of updates. In this paper, we provide a comprehensive performance evaluation of the main state-of-the-art broadcast rate control algorithms from the point of view of channel load, utilization efficiency, and information freshness. We evaluate these algorithms in a realistic simulation environment and describe a centralized approach to define a bound on the performance. We show that controlling the congestion based on either channel load or information freshness only leads to sub-optimal performance.
{"title":"An Age-Of-Information Perspective on Decentralized Congestion Control in Vehicular Networks","authors":"Ion Turcanu, A. Baiocchi, Nikita Lyamin, A. Vinel","doi":"10.1109/MedComNet52149.2021.9501273","DOIUrl":"https://doi.org/10.1109/MedComNet52149.2021.9501273","url":null,"abstract":"Vehicular networking enables a wide range of emerging Cooperative Intelligent Transportation System (C-ITS) applications, from safety to traffic efficiency and infotainment. Many of these applications depend on the reliability and timeliness of status information periodically exchanged among vehicles on the same wireless communication channel. A major effort has been spent, especially by standardization bodies, to define congestion control algorithms for the vehicular networking environment. The picture is, however, more complex than simply controlling the load level on the channel, given the non-trivial interplay of delivery reliability, system throughput, and timeliness of updates. In this paper, we provide a comprehensive performance evaluation of the main state-of-the-art broadcast rate control algorithms from the point of view of channel load, utilization efficiency, and information freshness. We evaluate these algorithms in a realistic simulation environment and describe a centralized approach to define a bound on the performance. We show that controlling the congestion based on either channel load or information freshness only leads to sub-optimal performance.","PeriodicalId":272937,"journal":{"name":"2021 19th Mediterranean Communication and Computer Networking Conference (MedComNet)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126419877","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 : 2021-06-15DOI: 10.1109/MedComNet52149.2021.9501277
Marco Zambianco, G. Verticale
5G RAN slicing makes it possible to simultaneously support enhanced mobile broadband (eMBB) and ultra-reliable low-latency communications (URLLC) services characterized by different numerologies over a shared radio physical layer. However, the inter-numerology interference (INI) generated by the multiplexing of spectrum slices having heterogeneous subcarrier spacing can hinder the service provisioning performance of both slices. In this context, we propose a spectrum allocation scheme capable of meeting the eMBB and URLLC service requirements while also mitigating the INI affecting each user. To overcome the computational complexity of the optimization problem, we design an INI-aware agent, based on Branching Dueling Q-networks (BDQ), which allocates a suitable number of spectrum resources to each user in order to satisfy the service requirements. In addition, we boost the agent learning efficiency by designing an action masking module that removes unfeasible actions. We compare the agent performance to state-of-the-art resource allocation algorithms that do not account for the INI. Results reveal that the proposed agent outperforms the considered benchmark schemes by ensuring a higher eMBB user data rate and, at the same time, a lower URLLC user delay.
{"title":"Mixed-Numerology Interference-Aware Spectrum Allocation for eMBB and URLLC Network Slices","authors":"Marco Zambianco, G. Verticale","doi":"10.1109/MedComNet52149.2021.9501277","DOIUrl":"https://doi.org/10.1109/MedComNet52149.2021.9501277","url":null,"abstract":"5G RAN slicing makes it possible to simultaneously support enhanced mobile broadband (eMBB) and ultra-reliable low-latency communications (URLLC) services characterized by different numerologies over a shared radio physical layer. However, the inter-numerology interference (INI) generated by the multiplexing of spectrum slices having heterogeneous subcarrier spacing can hinder the service provisioning performance of both slices. In this context, we propose a spectrum allocation scheme capable of meeting the eMBB and URLLC service requirements while also mitigating the INI affecting each user. To overcome the computational complexity of the optimization problem, we design an INI-aware agent, based on Branching Dueling Q-networks (BDQ), which allocates a suitable number of spectrum resources to each user in order to satisfy the service requirements. In addition, we boost the agent learning efficiency by designing an action masking module that removes unfeasible actions. We compare the agent performance to state-of-the-art resource allocation algorithms that do not account for the INI. Results reveal that the proposed agent outperforms the considered benchmark schemes by ensuring a higher eMBB user data rate and, at the same time, a lower URLLC user delay.","PeriodicalId":272937,"journal":{"name":"2021 19th Mediterranean Communication and Computer Networking Conference (MedComNet)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126506008","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 : 2021-06-15DOI: 10.1109/MedComNet52149.2021.9501276
Alessandro Galeazzi, L. Badia, Shih-Chung Chang, F. Gringoli
The cognitive radio network paradigm increases spectrum usage efficiency by allowing secondary users to perform shared access to licensed spectrum. This systematic improvement may be obtained in a practical way by implementing a distributed cooperative spectrum sensing mechanism. Although such decentralized sensing offers many advantages, it also opens the door to new security threats such as spectrum sensing data falsification attacks. In this work, we design a new mechanism that exploits sensing correlation through the concept of reputation to enhance resilience against this type of threat. By both theoretical analysis and simulations, we show that our proposal provides incentives for cooperation among honest devices and reduces the spectrum occupancy assessment error rate in the presence of malicious users.
{"title":"Reputation-Based Spectrum Data Fusion against Falsification Attacks in Cognitive Networks","authors":"Alessandro Galeazzi, L. Badia, Shih-Chung Chang, F. Gringoli","doi":"10.1109/MedComNet52149.2021.9501276","DOIUrl":"https://doi.org/10.1109/MedComNet52149.2021.9501276","url":null,"abstract":"The cognitive radio network paradigm increases spectrum usage efficiency by allowing secondary users to perform shared access to licensed spectrum. This systematic improvement may be obtained in a practical way by implementing a distributed cooperative spectrum sensing mechanism. Although such decentralized sensing offers many advantages, it also opens the door to new security threats such as spectrum sensing data falsification attacks. In this work, we design a new mechanism that exploits sensing correlation through the concept of reputation to enhance resilience against this type of threat. By both theoretical analysis and simulations, we show that our proposal provides incentives for cooperation among honest devices and reduces the spectrum occupancy assessment error rate in the presence of malicious users.","PeriodicalId":272937,"journal":{"name":"2021 19th Mediterranean Communication and Computer Networking Conference (MedComNet)","volume":"240 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116872963","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 : 2021-06-15DOI: 10.1109/MedComNet52149.2021.9501271
Mohamed Moulay, F. D. Muñoz, V. Mancuso
With the growth of the internet, current transport protocols are being re-evaluated to deal with traffic growth. QUIC is an evolving transport-layer protocol that has been developed to reduce Web latency, integrate security features, and enable a high-quality experience for mobile users. However, few systematic experimental studies have been carried out to evaluate users' service in a realistic mobile environment. In this work, we describe the design of experiments with QUIC and HTTP/3, which is based on QUIC, also considering benchmarks and variants in QUIC's implementations. We report our measurements collected from real mobile networks with the pan-European MONROE platform. Using data from the application, transport, and network layers in different wireless environments, we experimentally investigate and compare the performance of QUIC and HTTP/3 for static and mobile cellular users of several networks across Europe. Initial results show that QUIC-based operations are advantageous in case of users that move, and they are also strongly affected by the congestion control algorithm chosen for QUIC.
{"title":"On the Experimental Assessment of QUIC and Congestion Control Schemes in Cellular Networks","authors":"Mohamed Moulay, F. D. Muñoz, V. Mancuso","doi":"10.1109/MedComNet52149.2021.9501271","DOIUrl":"https://doi.org/10.1109/MedComNet52149.2021.9501271","url":null,"abstract":"With the growth of the internet, current transport protocols are being re-evaluated to deal with traffic growth. QUIC is an evolving transport-layer protocol that has been developed to reduce Web latency, integrate security features, and enable a high-quality experience for mobile users. However, few systematic experimental studies have been carried out to evaluate users' service in a realistic mobile environment. In this work, we describe the design of experiments with QUIC and HTTP/3, which is based on QUIC, also considering benchmarks and variants in QUIC's implementations. We report our measurements collected from real mobile networks with the pan-European MONROE platform. Using data from the application, transport, and network layers in different wireless environments, we experimentally investigate and compare the performance of QUIC and HTTP/3 for static and mobile cellular users of several networks across Europe. Initial results show that QUIC-based operations are advantageous in case of users that move, and they are also strongly affected by the congestion control algorithm chosen for QUIC.","PeriodicalId":272937,"journal":{"name":"2021 19th Mediterranean Communication and Computer Networking Conference (MedComNet)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125564692","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 : 2021-06-15DOI: 10.1109/MedComNet52149.2021.9501241
KienTrung Ngo, S. Mangione, I. Tinnirello
In this paper, we consider integrating VLC and WiFi technologies in a scenario in which Light-Emitting-Diodes (LEDs), acting as network access points (APs) for ultra-dense Internet of Things applications, are deployed into an indoor lighting infrastructure. In such a scenario, RF-links can be exploited for complementing VLC-links in dealing with mobility and bidirectional communications, which can be problematic due to the limited coverage areas and self-generated interference of VLC APs. In particular, we consider the possibility of supporting a technology-based duplexing scheme, in which downlink and uplink transmissions are performed by means, respectively, of VLC and WiFi interfaces integrated into the same node. In order to fully exploit the VLC bandwidth in the presence of background WiFi traffic and multiple coexisting VLC links, we discuss the importance of adopting a prioritization mechanism based on EDCA, as well as frame aggregation, for the uplink channel of the integrated architecture. Our considerations are corroborated by numerical results based on NS-3 simulations and a real simple experiment.
{"title":"Exploiting EDCA for Feedback Channels in Hybrid VLC/WiFi Architectures","authors":"KienTrung Ngo, S. Mangione, I. Tinnirello","doi":"10.1109/MedComNet52149.2021.9501241","DOIUrl":"https://doi.org/10.1109/MedComNet52149.2021.9501241","url":null,"abstract":"In this paper, we consider integrating VLC and WiFi technologies in a scenario in which Light-Emitting-Diodes (LEDs), acting as network access points (APs) for ultra-dense Internet of Things applications, are deployed into an indoor lighting infrastructure. In such a scenario, RF-links can be exploited for complementing VLC-links in dealing with mobility and bidirectional communications, which can be problematic due to the limited coverage areas and self-generated interference of VLC APs. In particular, we consider the possibility of supporting a technology-based duplexing scheme, in which downlink and uplink transmissions are performed by means, respectively, of VLC and WiFi interfaces integrated into the same node. In order to fully exploit the VLC bandwidth in the presence of background WiFi traffic and multiple coexisting VLC links, we discuss the importance of adopting a prioritization mechanism based on EDCA, as well as frame aggregation, for the uplink channel of the integrated architecture. Our considerations are corroborated by numerical results based on NS-3 simulations and a real simple experiment.","PeriodicalId":272937,"journal":{"name":"2021 19th Mediterranean Communication and Computer Networking Conference (MedComNet)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131170307","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 : 2021-06-15DOI: 10.1109/MedComNet52149.2021.9501279
Federico Mason, G. Nencioni, A. Zanella
The Network Slicing (NS) paradigm is one of the pillars of the future 5G networks and is gathering great attention from both industry and scientific communities. In a NS scenario, physical and virtual resources are partitioned among multiple logical networks, named slices, with specific characteristics. The challenge consists in finding efficient strategies to dynamically allocate the network resources among the different slices according to the user requirements. In this paper, we tackle the target problem by exploiting a Deep Reinforcement Learning approach. Our framework is based on a distributed architecture, where multiple agents cooperate towards a common goal. The agent training is carried out following the Advantage Actor Critic algorithm, which makes it possible to handle continuous action spaces. By means of extensive simulations, we show that our strategy yields better performance than an efficient empirical algorithm, while ensuring high adaptability to different scenarios without the need for additional training.
{"title":"A Multi-Agent Reinforcement Learning Architecture for Network Slicing Orchestration","authors":"Federico Mason, G. Nencioni, A. Zanella","doi":"10.1109/MedComNet52149.2021.9501279","DOIUrl":"https://doi.org/10.1109/MedComNet52149.2021.9501279","url":null,"abstract":"The Network Slicing (NS) paradigm is one of the pillars of the future 5G networks and is gathering great attention from both industry and scientific communities. In a NS scenario, physical and virtual resources are partitioned among multiple logical networks, named slices, with specific characteristics. The challenge consists in finding efficient strategies to dynamically allocate the network resources among the different slices according to the user requirements. In this paper, we tackle the target problem by exploiting a Deep Reinforcement Learning approach. Our framework is based on a distributed architecture, where multiple agents cooperate towards a common goal. The agent training is carried out following the Advantage Actor Critic algorithm, which makes it possible to handle continuous action spaces. By means of extensive simulations, we show that our strategy yields better performance than an efficient empirical algorithm, while ensuring high adaptability to different scenarios without the need for additional training.","PeriodicalId":272937,"journal":{"name":"2021 19th Mediterranean Communication and Computer Networking Conference (MedComNet)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129073116","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 : 2021-06-15DOI: 10.1109/MedComNet52149.2021.9501234
Alessandro Cornacchia, G. Sviridov, P. Giaccone, A. Bianco
Sketches have emerged as a powerful tool for network traffic monitoring due to the good trade-off between accuracy and memory footprint offered by such techniques. Yet, implementing sketches on commercial switches raises numerous challenges related to availability of memory and its access frequency. Recently, disaggregated sketches, i.e., fragments of single network-wide sketches distributed across multiple switches, were introduced to cope with these limitations. However, none of the current approaches exploit any knowledge about the network traffic patterns when deploying such schemes. In this paper, we investigate the impact of traffic patterns on the performance of disaggregated sketches. Our findings show that blindly updating all fragments of a sketch might degrade the monitoring accuracy. Instead, taking into account the spatial distribution of the traffic may lead to globally better monitoring accuracy. Finally, we provide hints on the existence of an optimal solution for such a problem which opens new opportunities for the design of traffic-aware update policies for sketches.
{"title":"A Traffic-Aware Perspective on Network Disaggregated Sketches","authors":"Alessandro Cornacchia, G. Sviridov, P. Giaccone, A. Bianco","doi":"10.1109/MedComNet52149.2021.9501234","DOIUrl":"https://doi.org/10.1109/MedComNet52149.2021.9501234","url":null,"abstract":"Sketches have emerged as a powerful tool for network traffic monitoring due to the good trade-off between accuracy and memory footprint offered by such techniques. Yet, implementing sketches on commercial switches raises numerous challenges related to availability of memory and its access frequency. Recently, disaggregated sketches, i.e., fragments of single network-wide sketches distributed across multiple switches, were introduced to cope with these limitations. However, none of the current approaches exploit any knowledge about the network traffic patterns when deploying such schemes. In this paper, we investigate the impact of traffic patterns on the performance of disaggregated sketches. Our findings show that blindly updating all fragments of a sketch might degrade the monitoring accuracy. Instead, taking into account the spatial distribution of the traffic may lead to globally better monitoring accuracy. Finally, we provide hints on the existence of an optimal solution for such a problem which opens new opportunities for the design of traffic-aware update policies for sketches.","PeriodicalId":272937,"journal":{"name":"2021 19th Mediterranean Communication and Computer Networking Conference (MedComNet)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127811492","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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