In this paper, interference alignment (IA) in 3-tier heterogeneous networks (HetNets) is addressed. The rank constrained rank minimization (RCRM) approach is modified to deal with the nature of tiers with different quality-of-service (QoS) requirements. In the proposed approach, which we name weighted RCRM (WRCRM), different tiers are treated with different weighting factors to reflect their tolerance to interference. We first study the achievable degrees of freedom (DoFs) for the 3-user mutually interfering broadcast channels (MIBCs) and derive an inner and a loose outer bound on the achievable DoFs. Then, using the derived expressions and the condition of IA feasibility, we show that, by choosing the appropriate weighting factors, the proposed WRCRM-IA solution can outperform the RCRM-IA approach in terms of the average sum rate and the average number of DoFs. Moreover, the WRCRM-IA solution comes closer to the perfect IA DoFs outer bound.
{"title":"Weighted rank constrained rank minimization interference alignment for 3-tier downlink heterogeneous networks","authors":"A. M. Benaya, M. Elsabrouty","doi":"10.1109/WD.2017.7918120","DOIUrl":"https://doi.org/10.1109/WD.2017.7918120","url":null,"abstract":"In this paper, interference alignment (IA) in 3-tier heterogeneous networks (HetNets) is addressed. The rank constrained rank minimization (RCRM) approach is modified to deal with the nature of tiers with different quality-of-service (QoS) requirements. In the proposed approach, which we name weighted RCRM (WRCRM), different tiers are treated with different weighting factors to reflect their tolerance to interference. We first study the achievable degrees of freedom (DoFs) for the 3-user mutually interfering broadcast channels (MIBCs) and derive an inner and a loose outer bound on the achievable DoFs. Then, using the derived expressions and the condition of IA feasibility, we show that, by choosing the appropriate weighting factors, the proposed WRCRM-IA solution can outperform the RCRM-IA approach in terms of the average sum rate and the average number of DoFs. Moreover, the WRCRM-IA solution comes closer to the perfect IA DoFs outer bound.","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124666676","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}
We first propose a framework which utilizes vehicular delay tolerant network (DTN) to form a vehicular cloud in order to provide information exchange without communication infrastructure. The framework does not rely on cellular network and therefore provides an approach which is suitable for post-disaster communication where cellular network is unavailable or severely congested. The paper also proposes a protocol which is able to provide vehicle-to-cloud communication in frequently changing vehicular environment. The protocol takes into account the link throughput, additional signal coverage, connection time, and the probability to encounter a RSU for the forwarder selection by using a fuzzy logic-based approach. The protocol also employs a network coding approach to reduce the overhead while maintaining a high data delivery ratio. We use computer simulations to evaluate the proposed framework.
{"title":"DTN-based vehicular cloud for post-disaster information sharing","authors":"Celimuge Wu, T. Yoshinaga, Yusheng Ji","doi":"10.1109/WD.2017.7918136","DOIUrl":"https://doi.org/10.1109/WD.2017.7918136","url":null,"abstract":"We first propose a framework which utilizes vehicular delay tolerant network (DTN) to form a vehicular cloud in order to provide information exchange without communication infrastructure. The framework does not rely on cellular network and therefore provides an approach which is suitable for post-disaster communication where cellular network is unavailable or severely congested. The paper also proposes a protocol which is able to provide vehicle-to-cloud communication in frequently changing vehicular environment. The protocol takes into account the link throughput, additional signal coverage, connection time, and the probability to encounter a RSU for the forwarder selection by using a fuzzy logic-based approach. The protocol also employs a network coding approach to reduce the overhead while maintaining a high data delivery ratio. We use computer simulations to evaluate the proposed framework.","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132389717","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 many Internet of Things (IoT) Infrastructures having been implemented in recent years, none of them is truly prepared for a global deployment, where failure tolerance and scalability are an essential requirement. This article presents an alternative concept for IoT Infrastructures, which focuses on enhancing the traditional centralized architecture, usually operated by a single entity, into a decentralized architecture featuring multiple business roles. We propose a dynamic and self-configurable infrastructure on top of a structured Peer-to-Peer network. In addition, a set of communication protocols are provided in order to support heterogeneous devices, as well as data access, streaming and persistence. It is also an important focus of our proposal to have mechanisms that guarantee the privacy and security of the information flow and storage.
{"title":"Secure decentralized IoT Infrastructure","authors":"Vasco Santos, J. Barraca, D. Gomes","doi":"10.1109/WD.2017.7918137","DOIUrl":"https://doi.org/10.1109/WD.2017.7918137","url":null,"abstract":"Despite many Internet of Things (IoT) Infrastructures having been implemented in recent years, none of them is truly prepared for a global deployment, where failure tolerance and scalability are an essential requirement. This article presents an alternative concept for IoT Infrastructures, which focuses on enhancing the traditional centralized architecture, usually operated by a single entity, into a decentralized architecture featuring multiple business roles. We propose a dynamic and self-configurable infrastructure on top of a structured Peer-to-Peer network. In addition, a set of communication protocols are provided in order to support heterogeneous devices, as well as data access, streaming and persistence. It is also an important focus of our proposal to have mechanisms that guarantee the privacy and security of the information flow and storage.","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132139170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper proposes new cooperative protocols based on energy harvesting relays. The protocols are based on the time switching and power splitting receiver architectures. The proposed protocols provide a fair cooperation, such that the relay does not use its own energy to help the source but harvests energy from the source signal. Assuming that the source knows channel statistics, the throughput achieved by the protocols can be larger than that of direct transmission depending on system parameters. We provide analytical expressions of the outage probability and study the effect of various system parameters on the performance of the protocols.
{"title":"Cooperative communication protocols with energy harvesting relays","authors":"Zeina Mheich, V. Savin","doi":"10.1109/WD.2017.7918116","DOIUrl":"https://doi.org/10.1109/WD.2017.7918116","url":null,"abstract":"This paper proposes new cooperative protocols based on energy harvesting relays. The protocols are based on the time switching and power splitting receiver architectures. The proposed protocols provide a fair cooperation, such that the relay does not use its own energy to help the source but harvests energy from the source signal. Assuming that the source knows channel statistics, the throughput achieved by the protocols can be larger than that of direct transmission depending on system parameters. We provide analytical expressions of the outage probability and study the effect of various system parameters on the performance of the protocols.","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126111169","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}
Simon Wunderlich, Frank Gabriel, Sreekrishna Pandi, F. Fitzek
Random Linear Network Coding (RLNC) is a popular coding scheme to improve communication over lossy channels. For packet streaming applications (video streaming, general IP streams), recent research has shown that sliding window schemes can improve in-order delay properties compared to the block/-generation based coding. However, implementing sliding window RLNC with a limited coding window poses new challenges in both theoretical and engineering aspects. We introduce the first practical generation-less sliding window RLNC scheme, which is built on existing generation based coders. Through discrete simulation and a proof of concept implementation, we show that, the in-order delay can be improved compared to generation based schemes while retaining the reliability, computational complexity and overhead.
{"title":"We don't need no generation - a practical approach to sliding window RLNC","authors":"Simon Wunderlich, Frank Gabriel, Sreekrishna Pandi, F. Fitzek","doi":"10.1109/WD.2017.7918148","DOIUrl":"https://doi.org/10.1109/WD.2017.7918148","url":null,"abstract":"Random Linear Network Coding (RLNC) is a popular coding scheme to improve communication over lossy channels. For packet streaming applications (video streaming, general IP streams), recent research has shown that sliding window schemes can improve in-order delay properties compared to the block/-generation based coding. However, implementing sliding window RLNC with a limited coding window poses new challenges in both theoretical and engineering aspects. We introduce the first practical generation-less sliding window RLNC scheme, which is built on existing generation based coders. Through discrete simulation and a proof of concept implementation, we show that, the in-order delay can be improved compared to generation based schemes while retaining the reliability, computational complexity and overhead.","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126915008","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}
C. Calafate, Karin Cicenia, Óscar Alvear, Juan-Carlos Cano, P. Manzoni
Vehicles are key elements in the envisioned Smart Cities, not only providing more efficient mobility, but also becoming mobile network elements able to perform many useful tasks. Environment sensing is a good example where the combination of data coming from vehicles allows achieving insight only comparable to the deployment of hundreds or thousands of sensors in a city. Obtaining rainfall estimations with a high spatial granularity is an example of a task where relying on traditional methods would become too expensive due to the high number of data sources required. Vehicular networking has a great potential to address such challenge by converting every vehicle in a rain sensor. In this paper we carry out a simulation study to estimate the rainfall intensity in a specific area using a vehicular network as data source. To this purpose, we model a rainfall pattern taking real values as reference, and we devise a simulation scenario where the rainfall pattern is deployed. Experimental results using the OMNeT++ simulator show that, even with a low density of vehicles contributing to the proposed monitoring system, rainfall intensity can still be predicted with a high accuracy and granularity, thereby validating the proposed approach.
{"title":"Estimating rainfall intensity by using vehicles as sensors","authors":"C. Calafate, Karin Cicenia, Óscar Alvear, Juan-Carlos Cano, P. Manzoni","doi":"10.1109/WD.2017.7918109","DOIUrl":"https://doi.org/10.1109/WD.2017.7918109","url":null,"abstract":"Vehicles are key elements in the envisioned Smart Cities, not only providing more efficient mobility, but also becoming mobile network elements able to perform many useful tasks. Environment sensing is a good example where the combination of data coming from vehicles allows achieving insight only comparable to the deployment of hundreds or thousands of sensors in a city. Obtaining rainfall estimations with a high spatial granularity is an example of a task where relying on traditional methods would become too expensive due to the high number of data sources required. Vehicular networking has a great potential to address such challenge by converting every vehicle in a rain sensor. In this paper we carry out a simulation study to estimate the rainfall intensity in a specific area using a vehicular network as data source. To this purpose, we model a rainfall pattern taking real values as reference, and we devise a simulation scenario where the rainfall pattern is deployed. Experimental results using the OMNeT++ simulator show that, even with a low density of vehicles contributing to the proposed monitoring system, rainfall intensity can still be predicted with a high accuracy and granularity, thereby validating the proposed approach.","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"189 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128611418","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}
Rodrigue Domga Komguem, Razvan Stanica, M. Tchuenté, F. Valois
In wireless sensor networks with linear topology, knowing the physical order in which nodes are deployed is useful not only for the target application, but also to some network services, like routing or data aggregation. Considering the limited resources of sensor nodes, the design of autonomous protocols to find this order is a challenging topic. In this paper, we propose a distributed and iterative centroid-based algorithm to address this problem. At each iteration, the algorithm selects two virtual anchors and finds the order of a subset of nodes, placed between these two anchors. The proposed algorithm requires local node connectivity knowledge and the identifier of the first sensor node of the network, which is the only manually configured parameter. This solution, scalable and lightweight from the deployment and maintenance point of view, is shown to be robust to connectivity degradation, correctly ordering more than 95% of the nodes, even under very low connectivity conditions
{"title":"Node ranking in wireless sensor networks with linear topology","authors":"Rodrigue Domga Komguem, Razvan Stanica, M. Tchuenté, F. Valois","doi":"10.1109/WD.2017.7918127","DOIUrl":"https://doi.org/10.1109/WD.2017.7918127","url":null,"abstract":"In wireless sensor networks with linear topology, knowing the physical order in which nodes are deployed is useful not only for the target application, but also to some network services, like routing or data aggregation. Considering the limited resources of sensor nodes, the design of autonomous protocols to find this order is a challenging topic. In this paper, we propose a distributed and iterative centroid-based algorithm to address this problem. At each iteration, the algorithm selects two virtual anchors and finds the order of a subset of nodes, placed between these two anchors. The proposed algorithm requires local node connectivity knowledge and the identifier of the first sensor node of the network, which is the only manually configured parameter. This solution, scalable and lightweight from the deployment and maintenance point of view, is shown to be robust to connectivity degradation, correctly ordering more than 95% of the nodes, even under very low connectivity conditions","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127853357","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}
Shohei Yoshioka, S. Suyama, Tatsuki Okuyama, Jun Mashino, Y. Okumura
The fifth-generation (5G) mobile communication system will utilize higher frequency bands with wider bandwidth for super high bit rate and large system capacity. Massive multiple-input multiple-output (Massive MIMO) beamforming (BF) technology has attracted much attention to compensate larger path-loss of a disadvantage at higher frequency bands. In low-SHF bands, approximately 100 MHz bandwidth is assumed, thus fully-digital Massive MIMO having flexibility of BF can be applied. In this paper, we modify joint processing of analog fixed BF and channel state information (CSI)-based precoding (called FBCP), which is a hybrid BF technology, to fully-digital method (called Digital-FBCP). Although conventional studies about Massive MIMO with BF do not take account of channel estimation (CE) in detail, this paper describes two-stage CE required for multi-user (MU) Massive MIMO with BF. Throughput performance is evaluated by link level computer simulation in consideration of the reference design and pilot insertion loss. This paper shows that Digital-FBCP achieves almost equal or better throughput performance than conventional precoding (PR) without fixed BF.
{"title":"5G massive MIMO with digital beamforming and two-stage channel estimation for low SHF band","authors":"Shohei Yoshioka, S. Suyama, Tatsuki Okuyama, Jun Mashino, Y. Okumura","doi":"10.1109/WD.2017.7918124","DOIUrl":"https://doi.org/10.1109/WD.2017.7918124","url":null,"abstract":"The fifth-generation (5G) mobile communication system will utilize higher frequency bands with wider bandwidth for super high bit rate and large system capacity. Massive multiple-input multiple-output (Massive MIMO) beamforming (BF) technology has attracted much attention to compensate larger path-loss of a disadvantage at higher frequency bands. In low-SHF bands, approximately 100 MHz bandwidth is assumed, thus fully-digital Massive MIMO having flexibility of BF can be applied. In this paper, we modify joint processing of analog fixed BF and channel state information (CSI)-based precoding (called FBCP), which is a hybrid BF technology, to fully-digital method (called Digital-FBCP). Although conventional studies about Massive MIMO with BF do not take account of channel estimation (CE) in detail, this paper describes two-stage CE required for multi-user (MU) Massive MIMO with BF. Throughput performance is evaluated by link level computer simulation in consideration of the reference design and pilot insertion loss. This paper shows that Digital-FBCP achieves almost equal or better throughput performance than conventional precoding (PR) without fixed BF.","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122375140","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 IEEE 802.11p is the de-facto vehicular radio communication technology for road safety and efficiency applications. With the advancements in the autonomous vehicle technology, studies on applicability of the IEEE 802.11p and the related protocols for the autonomous driving applications are needed. In this paper, we study the impacts of vehicular communication on platooning control considering that the ETSI-standardised message set Cooperative Awareness Message (CAM) and the IEEE 802.11p are used for both the platooning and cooperative awareness applications. We first develop a theoretical model for the probability of a successful CAM transmission over IEEE 802.11p between platoon members by taking account of the existence of non-platoon vehicles on the road. The model is verified by comparing against simulation results obtained from the NS3 simulator. Finally, we investigate the impacts of the communication performance on the behaviour of platoons, specially the chain stability, when hundreds of vehicles share the wireless channel. The theoretical model reveals that thanks to the capture effect, communications between platoon members drastically outperform communications between arbitrary two vehicles on the road. The simulation results show that in contrast to an adaptive cruise control (ACC), which does not use vehicular communication, the IEEE 802.11p based vehicle to vehicle (V2V) communication aids for realizing stable platoons in highway scenarios.
{"title":"Performance study of CAM over IEEE 802.11p for cooperative adaptive cruise control","authors":"O. Shagdar, F. Nashashibi, S. Tohmé","doi":"10.1109/WD.2017.7918118","DOIUrl":"https://doi.org/10.1109/WD.2017.7918118","url":null,"abstract":"The IEEE 802.11p is the de-facto vehicular radio communication technology for road safety and efficiency applications. With the advancements in the autonomous vehicle technology, studies on applicability of the IEEE 802.11p and the related protocols for the autonomous driving applications are needed. In this paper, we study the impacts of vehicular communication on platooning control considering that the ETSI-standardised message set Cooperative Awareness Message (CAM) and the IEEE 802.11p are used for both the platooning and cooperative awareness applications. We first develop a theoretical model for the probability of a successful CAM transmission over IEEE 802.11p between platoon members by taking account of the existence of non-platoon vehicles on the road. The model is verified by comparing against simulation results obtained from the NS3 simulator. Finally, we investigate the impacts of the communication performance on the behaviour of platoons, specially the chain stability, when hundreds of vehicles share the wireless channel. The theoretical model reveals that thanks to the capture effect, communications between platoon members drastically outperform communications between arbitrary two vehicles on the road. The simulation results show that in contrast to an adaptive cruise control (ACC), which does not use vehicular communication, the IEEE 802.11p based vehicle to vehicle (V2V) communication aids for realizing stable platoons in highway scenarios.","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"202 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123966563","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}
WiFi-based Long Distance (WiLD) networks have emerged as a promising alternative approach for Internet in rural areas. The main hardware components of these networks are commercial off-the-shelf WiFi radios and directional antennas. During our experiences with real-world WiLD networks, we encountered that interference among long-distance links is a major issue even with high gain directional antennas. In this work, we are providing an in-depth analysis of these interference effects by conducting simulations in ns-3. To closely match the real-world interference effects, we implemented a module to load radiation pattern of commonly used antennas. We analyze two different interference scenarios typically present as a part of larger networks. The results show that side-lobes of directional antennas significantly influence the throughput of long-distance WiFi links depending on the orientation. This work emphasizes that the usage of simple directional antenna models needs to be considered carefully.
{"title":"Interference of simulated IEEE 802.11 links with directional antennas","authors":"Michael Rademacher, K. Jonas","doi":"10.1109/WD.2017.7918110","DOIUrl":"https://doi.org/10.1109/WD.2017.7918110","url":null,"abstract":"WiFi-based Long Distance (WiLD) networks have emerged as a promising alternative approach for Internet in rural areas. The main hardware components of these networks are commercial off-the-shelf WiFi radios and directional antennas. During our experiences with real-world WiLD networks, we encountered that interference among long-distance links is a major issue even with high gain directional antennas. In this work, we are providing an in-depth analysis of these interference effects by conducting simulations in ns-3. To closely match the real-world interference effects, we implemented a module to load radiation pattern of commonly used antennas. We analyze two different interference scenarios typically present as a part of larger networks. The results show that side-lobes of directional antennas significantly influence the throughput of long-distance WiFi links depending on the orientation. This work emphasizes that the usage of simple directional antenna models needs to be considered carefully.","PeriodicalId":179998,"journal":{"name":"2017 Wireless Days","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124011430","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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