Pub Date : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6849028
Alican Gök, M. Koca
In this paper, we evaluate the intercell-interference coordination (ICIC) performances of frequency planning schemes in OFDMA cellular networks. In particular, universal frequency reuse (reuse-1), reuse-3, strict fractional frequency reuse (FFR) and soft frequency reuse (SFR) performances are evaluated. The performances of these frequency planning schemes are compared under different resource scheduling strategies via simulations to also measure the performance of each scheduler. Based on the simulation results, design trade-offs are outlined for ICIC techniques to be used in OFDMA networks.
{"title":"Performance evaluation of frequency planning and scheduling schemes in oFDMA Networks","authors":"Alican Gök, M. Koca","doi":"10.1109/BlackSeaCom.2014.6849028","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6849028","url":null,"abstract":"In this paper, we evaluate the intercell-interference coordination (ICIC) performances of frequency planning schemes in OFDMA cellular networks. In particular, universal frequency reuse (reuse-1), reuse-3, strict fractional frequency reuse (FFR) and soft frequency reuse (SFR) performances are evaluated. The performances of these frequency planning schemes are compared under different resource scheduling strategies via simulations to also measure the performance of each scheduler. Based on the simulation results, design trade-offs are outlined for ICIC techniques to be used in OFDMA networks.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128745939","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 : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6848995
Refik Caglar Kizilirmak, M. Uysal
In this study, we investigate a relay-assisted visible light communication (VLC) system where an intermediate light source cooperates with the main light source. Specifically, we consider two light sources in an office space; one is the information source employed on the ceiling and the other one is a task light mounted on a desk. Our system builds upon DC biased optical orthogonal frequency division multiplexing (DCO-OFDM). The task light performs amplify-and-forward relaying to assist the communication and operates in half-duplex mode. We investigate the error rate performance of the proposed OFDM-based relay-assisted VLC system. Furthermore, we present joint AC and DC optimal power allocation in order to improve the performance. The DC power allocation is controlled by sharing the number of LED chips between the terminals and the AC power allocation decides the fraction of the information signal energy to be consumed at the terminals. Simulation results reveal that the VLC system performance can be improved via relay-assisted transmission and the performance gain as much as 6 dB can be achieved.
{"title":"Relay-assisted OFDM transmission for indoor visible light communication","authors":"Refik Caglar Kizilirmak, M. Uysal","doi":"10.1109/BlackSeaCom.2014.6848995","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6848995","url":null,"abstract":"In this study, we investigate a relay-assisted visible light communication (VLC) system where an intermediate light source cooperates with the main light source. Specifically, we consider two light sources in an office space; one is the information source employed on the ceiling and the other one is a task light mounted on a desk. Our system builds upon DC biased optical orthogonal frequency division multiplexing (DCO-OFDM). The task light performs amplify-and-forward relaying to assist the communication and operates in half-duplex mode. We investigate the error rate performance of the proposed OFDM-based relay-assisted VLC system. Furthermore, we present joint AC and DC optimal power allocation in order to improve the performance. The DC power allocation is controlled by sharing the number of LED chips between the terminals and the AC power allocation decides the fraction of the information signal energy to be consumed at the terminals. Simulation results reveal that the VLC system performance can be improved via relay-assisted transmission and the performance gain as much as 6 dB can be achieved.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129947833","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 : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6849006
I. Demydov, B. Strykhalyuk, M. Klymash
These materials contain the physically- and mathematically-based representation of combined network hyper structures' meta-properties using their holographic definition and reconstruction principles, as well as similar approaches to representing, analyzing, prediction and storing of big amounts of the network-related proprietary data are given.
{"title":"The holographic network analysis","authors":"I. Demydov, B. Strykhalyuk, M. Klymash","doi":"10.1109/BlackSeaCom.2014.6849006","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6849006","url":null,"abstract":"These materials contain the physically- and mathematically-based representation of combined network hyper structures' meta-properties using their holographic definition and reconstruction principles, as well as similar approaches to representing, analyzing, prediction and storing of big amounts of the network-related proprietary data are given.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131970244","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 : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6849011
P. Freidl, Hasan Noor Khan, M. Gadringer, W. Bösch
In this paper, the analysis and the results of a measurement campaign for the communication channel of a mm-wave radio frequency identification (MMID) system are presented. The measurement setup was chosen to meet the requirements of a MMID application scenario. Using a vector network analyzer and custom made yagi-uda antennas, the channel was measured in the frequency range of 55 - 65 GHz. The measurement data was analyzed in the frequency domain and in the delay domain using the power delay profile. The power delay profile shows an influence of multipath propagation and delay dispersion. The variation of the channel transfer function over increasing distances can be approximated by the free space loss model.
{"title":"Measurements and analysis of MM-Wave RFID channels","authors":"P. Freidl, Hasan Noor Khan, M. Gadringer, W. Bösch","doi":"10.1109/BlackSeaCom.2014.6849011","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6849011","url":null,"abstract":"In this paper, the analysis and the results of a measurement campaign for the communication channel of a mm-wave radio frequency identification (MMID) system are presented. The measurement setup was chosen to meet the requirements of a MMID application scenario. Using a vector network analyzer and custom made yagi-uda antennas, the channel was measured in the frequency range of 55 - 65 GHz. The measurement data was analyzed in the frequency domain and in the delay domain using the power delay profile. The power delay profile shows an influence of multipath propagation and delay dispersion. The variation of the channel transfer function over increasing distances can be approximated by the free space loss model.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132116942","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 : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6848996
S. Kisseleff, I. Akyildiz, W. Gerstacker
The use of magnetic induction (MI) based transmissions in challenging environments has been investigated in various works. Recently, a system model has been proposed, which explains how the pathloss of the magnetic induction based transmissions depends on the system parameters. It is frequently assumed, that perfect channel state information (CSI) is available at the transmitter and at the receiver, such that the optimal set of system parameters can be determined in order to maximize the overall data rate. However, in practical systems this knowledge may not always be easily acquired. In addition, a permanent feedback signaling is needed, in order to update the CSI at the transmitter. This feedback signaling usually occupies several time slots and therefore reduces the bandwidth efficiency. An interesting aspect, which has been overlooked in the past, is the channel estimation and prediction of the received signal within the MI transmitter circuit without explicit feedback signaling of CSI. In this paper, we investigate the potential of this technique for the wireless underground sensor networks.
{"title":"Transmitter-side channel estimation in magnetic induction based communication systems","authors":"S. Kisseleff, I. Akyildiz, W. Gerstacker","doi":"10.1109/BlackSeaCom.2014.6848996","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6848996","url":null,"abstract":"The use of magnetic induction (MI) based transmissions in challenging environments has been investigated in various works. Recently, a system model has been proposed, which explains how the pathloss of the magnetic induction based transmissions depends on the system parameters. It is frequently assumed, that perfect channel state information (CSI) is available at the transmitter and at the receiver, such that the optimal set of system parameters can be determined in order to maximize the overall data rate. However, in practical systems this knowledge may not always be easily acquired. In addition, a permanent feedback signaling is needed, in order to update the CSI at the transmitter. This feedback signaling usually occupies several time slots and therefore reduces the bandwidth efficiency. An interesting aspect, which has been overlooked in the past, is the channel estimation and prediction of the received signal within the MI transmitter circuit without explicit feedback signaling of CSI. In this paper, we investigate the potential of this technique for the wireless underground sensor networks.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127987799","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 : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6849030
M. Klymash, M. Beshley, B. Strykhalyuk, T. Maksymyuk
Mobile Cloud Computing (MCC) is an integration of cloud computing in the mobile environment, which is used to improve the overall performance of the mobile devices. The rapid growth of cloud computing and mobile Internet services has triggered the emergence of mobile cloud services. Among many challenges, QoS management is one of the crucial issues for mobile cloud services. Here the survey of the current research related to QoS provision in mobile cloud computing is presented. The provision of QoS in mobile cloud computing is a challenging task. This is because of the dynamic characteristics of mobile networks and limited resources of mobile devices such as bandwidth, delay, packet loss ratio, battery life, storage capacity, computational power, security, etc. Also we present a cloud aware multimedia, which addresses how multimedia services and applications, such as storage and sharing, authoring and mashup, adaptation and delivery, and rendering and retrieval, can optimally utilize cloud-computing resources to achieve better quality of experience (QoE). The traffic of Lviv Polytechnic enterprise network have been analyzed. Simulation model processing of traffic in queues heterogeneity network on the basis of services priorities has been developed.
{"title":"Research and development the methods of quality of service provision in Mobile Cloud systems","authors":"M. Klymash, M. Beshley, B. Strykhalyuk, T. Maksymyuk","doi":"10.1109/BlackSeaCom.2014.6849030","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6849030","url":null,"abstract":"Mobile Cloud Computing (MCC) is an integration of cloud computing in the mobile environment, which is used to improve the overall performance of the mobile devices. The rapid growth of cloud computing and mobile Internet services has triggered the emergence of mobile cloud services. Among many challenges, QoS management is one of the crucial issues for mobile cloud services. Here the survey of the current research related to QoS provision in mobile cloud computing is presented. The provision of QoS in mobile cloud computing is a challenging task. This is because of the dynamic characteristics of mobile networks and limited resources of mobile devices such as bandwidth, delay, packet loss ratio, battery life, storage capacity, computational power, security, etc. Also we present a cloud aware multimedia, which addresses how multimedia services and applications, such as storage and sharing, authoring and mashup, adaptation and delivery, and rendering and retrieval, can optimally utilize cloud-computing resources to achieve better quality of experience (QoE). The traffic of Lviv Polytechnic enterprise network have been analyzed. Simulation model processing of traffic in queues heterogeneity network on the basis of services priorities has been developed.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127457889","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 : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6849015
A. Anisimov, I. Zavadskyi
A new class of forward error correcting codes is introduced. The main idea of the code construction is to utilize special arithmetic properties of input words and codewords considered as whole numbers in the process of encoding and decoding. The numbers are represented in the two-base numeration system with the main radix 2 and the auxiliary radix 3.
{"title":"Forward error correcting codes by means of the two-base (2,3)-numeration system","authors":"A. Anisimov, I. Zavadskyi","doi":"10.1109/BlackSeaCom.2014.6849015","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6849015","url":null,"abstract":"A new class of forward error correcting codes is introduced. The main idea of the code construction is to utilize special arithmetic properties of input words and codewords considered as whole numbers in the process of encoding and decoding. The numbers are represented in the two-base numeration system with the main radix 2 and the auxiliary radix 3.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132843996","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 : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6849010
Sooyoung Hur, Yeon-Jea Cho, JungAun Lee, Noh-Gyoung Kang, Jeongho Park, H. Benn
The millimeter wave band will be a key component in the next generation wireless communication system (5G), and a proper channel model is needed for developing the future 5G cellular technologies. This paper introduces a 28 GHz channel sounder based on automatically rotating horn antennas with time synchronization ability between the transmitter (TX) and the receiver (RX). We have developed a sounding method for synchronized measurement using the proposed channel sounder system which records time-stamping to measure the relative propagation time from the transmitter to receiver. The proposed approach allows us to generate an omni-like channel measurements by synthesizing all directional measurements, which have been verified by comparison with the measurements of omni-directional antennas. Subsequently, the omni-directional propagation measurement results are provided in an in-building environment similar to a small shopping mall. From the measurements, the clustering analysis has been done including its power distribution. This paper provides the first channel sounder and initial results to obtain the synthesized omni-directional results in millimeter wave 28 GHz band.
{"title":"Synchronous channel sounder using horn antenna and indoor measurements on 28 GHz","authors":"Sooyoung Hur, Yeon-Jea Cho, JungAun Lee, Noh-Gyoung Kang, Jeongho Park, H. Benn","doi":"10.1109/BlackSeaCom.2014.6849010","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6849010","url":null,"abstract":"The millimeter wave band will be a key component in the next generation wireless communication system (5G), and a proper channel model is needed for developing the future 5G cellular technologies. This paper introduces a 28 GHz channel sounder based on automatically rotating horn antennas with time synchronization ability between the transmitter (TX) and the receiver (RX). We have developed a sounding method for synchronized measurement using the proposed channel sounder system which records time-stamping to measure the relative propagation time from the transmitter to receiver. The proposed approach allows us to generate an omni-like channel measurements by synthesizing all directional measurements, which have been verified by comparison with the measurements of omni-directional antennas. Subsequently, the omni-directional propagation measurement results are provided in an in-building environment similar to a small shopping mall. From the measurements, the clustering analysis has been done including its power distribution. This paper provides the first channel sounder and initial results to obtain the synthesized omni-directional results in millimeter wave 28 GHz band.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130874713","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 : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6849023
E. Guardo, G. Morabito, Girolamo Catania, Agatino Mursia, Ferdinando Battiati
Mobile Ad Hoc Networks (MANET) are widely used in tactical scenarios because they can be deployed rapidly in hostile areas and the distributed nature of their operations makes them robust to nodes failures. However, distributed control involves new vulnerabilities that might be critical in electronic warfare scenarios. In this paper we focus on black hole attacks which introduce in the network fake routing information. On the consequence of the above information, the malicious node enters in the end-to-end path of most communication sessions and discards all received packets. In this paper a solution, named BRAVO is proposed, that exploits a mechanism based on credits allowing nodes to estimate the trustworthiness of neighboring nodes. Simulation results demonstrate that in most scenarios BRAVO is robust to black hole attacks.
{"title":"BRAVO: A black-hole resilient ad-hoc on demand distance Vector rOuting for tactical communications","authors":"E. Guardo, G. Morabito, Girolamo Catania, Agatino Mursia, Ferdinando Battiati","doi":"10.1109/BlackSeaCom.2014.6849023","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6849023","url":null,"abstract":"Mobile Ad Hoc Networks (MANET) are widely used in tactical scenarios because they can be deployed rapidly in hostile areas and the distributed nature of their operations makes them robust to nodes failures. However, distributed control involves new vulnerabilities that might be critical in electronic warfare scenarios. In this paper we focus on black hole attacks which introduce in the network fake routing information. On the consequence of the above information, the malicious node enters in the end-to-end path of most communication sessions and discards all received packets. In this paper a solution, named BRAVO is proposed, that exploits a mechanism based on credits allowing nodes to estimate the trustworthiness of neighboring nodes. Simulation results demonstrate that in most scenarios BRAVO is robust to black hole attacks.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130670716","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 : 2014-05-27DOI: 10.1109/BlackSeaCom.2014.6849036
S. Temel, I. Bekmezci
Flying Ad Hoc Network (FANET) is a novel mobile ad hoc network type where the communicating nodes are Unmanned Aerial Vehicles (UAVs). Deployment of traditional omnidirectional antennas on FANETs lacks to address enhanced spatial reuse demands because interference by simultaneous transmissions limits the maximum number of concurrent communications. Alternatively, utilization of directional antennas can significantly increase the spatial reuse and network capacity of FANETs. In this paper, we present an analytical study to specify the maximum number of active UAV node pairs for three dimensional (3D) flight scenarios. Specifically, we propose an analysis for various flight scenarios over different types of flights and present the effects of the distance between communicating nodes and the main beam angles on the number of maximum active node pairs.
{"title":"Scalability analysis of Flying Ad Hoc Networks (FANETs): A directional antenna approach","authors":"S. Temel, I. Bekmezci","doi":"10.1109/BlackSeaCom.2014.6849036","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2014.6849036","url":null,"abstract":"Flying Ad Hoc Network (FANET) is a novel mobile ad hoc network type where the communicating nodes are Unmanned Aerial Vehicles (UAVs). Deployment of traditional omnidirectional antennas on FANETs lacks to address enhanced spatial reuse demands because interference by simultaneous transmissions limits the maximum number of concurrent communications. Alternatively, utilization of directional antennas can significantly increase the spatial reuse and network capacity of FANETs. In this paper, we present an analytical study to specify the maximum number of active UAV node pairs for three dimensional (3D) flight scenarios. Specifically, we propose an analysis for various flight scenarios over different types of flights and present the effects of the distance between communicating nodes and the main beam angles on the number of maximum active node pairs.","PeriodicalId":427901,"journal":{"name":"2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124091858","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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