Pub Date : 2019-06-01DOI: 10.1109/BlackSeaCom.2019.8812875
D. Korepanova, Maria Nosyk, A. Ostrovsky, Y. Yanovich
Zero-knowledge proofs are an emerging cryptographic technology that have many potential applications for blockchains. Exonum is an extensible open-source framework for creating blockchain applications. In this article, we describe how zero-knowledge proofs, specifically bulletproofs, can be applied to build a privacy-focused service using Exonum. The token logic is implemented as a platform service and is a proof of concept.
{"title":"Building a Private Currency Service Using Exonum","authors":"D. Korepanova, Maria Nosyk, A. Ostrovsky, Y. Yanovich","doi":"10.1109/BlackSeaCom.2019.8812875","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2019.8812875","url":null,"abstract":"Zero-knowledge proofs are an emerging cryptographic technology that have many potential applications for blockchains. Exonum is an extensible open-source framework for creating blockchain applications. In this article, we describe how zero-knowledge proofs, specifically bulletproofs, can be applied to build a privacy-focused service using Exonum. The token logic is implemented as a platform service and is a proof of concept.","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131681298","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 : 2019-06-01DOI: 10.1109/BlackSeaCom.2019.8812811
M. Elamassie, M. Uysal
Underwater visible light communication (UVLC) is a high capacity wireless connectivity solution with low latency, particularly appealing for real-time underwater video and image transmission. While attenuation and geometrical losses determine the average light intensity, underwater optical turbulence introduces fluctuations on the average received intensity, also known as fading. Due to relative movements of source and/or detector in harsh underwater environment, pointing errors further cause additional fading. In this paper, we consider a vertical underwater link modeled as a multi-layer channel where the fading coefficients associated with each layer are modeled as independent but not identically distributed Gamma-Gamma random variables. We model the displacements along the horizontal and elevation axes as independent and identically distributed Gaussian variables. Under these assumptions, we derive a closed-form expression for bit error rate (BER) expression. Based on asymptotical BER analysis, we determine the diversity order as a function of system and channel parameters. We further present Monte-Carlo simulation results to confirm the derived expressions.
{"title":"Vertical Underwater VLC Links over Cascaded Gamma-Gamma Turbulence Channels with Pointing Errors","authors":"M. Elamassie, M. Uysal","doi":"10.1109/BlackSeaCom.2019.8812811","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2019.8812811","url":null,"abstract":"Underwater visible light communication (UVLC) is a high capacity wireless connectivity solution with low latency, particularly appealing for real-time underwater video and image transmission. While attenuation and geometrical losses determine the average light intensity, underwater optical turbulence introduces fluctuations on the average received intensity, also known as fading. Due to relative movements of source and/or detector in harsh underwater environment, pointing errors further cause additional fading. In this paper, we consider a vertical underwater link modeled as a multi-layer channel where the fading coefficients associated with each layer are modeled as independent but not identically distributed Gamma-Gamma random variables. We model the displacements along the horizontal and elevation axes as independent and identically distributed Gaussian variables. Under these assumptions, we derive a closed-form expression for bit error rate (BER) expression. Based on asymptotical BER analysis, we determine the diversity order as a function of system and channel parameters. We further present Monte-Carlo simulation results to confirm the derived expressions.","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128916350","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 : 2019-06-01DOI: 10.1109/BlackSeaCom.2019.8812820
N. Shilov, O. Smirnova, P. Morozova, Nikolay Turov, M. Shchekotov, N. Teslya
Providing information in smart cities is possible in various ways. Digital signage is one of such options. However, personalization and contextualization of digital signage is complicated due to both technological and legislative reasons. When providing contextual information to a group of users, consideration of preferences and interests of users is complicated by a number of additional problems, most of which are related to identifying preferences/interests common to this group of users, as well as to their confidentiality. At the moment, such solutions do not exist. The paper presents a methodology of building a personalized digital signage system taking into account confidentiality and using tacit feedback to clarify the information provided, as well as information about users.
{"title":"Digital Signage Personalization for Smart City: Major Requirements and Approach","authors":"N. Shilov, O. Smirnova, P. Morozova, Nikolay Turov, M. Shchekotov, N. Teslya","doi":"10.1109/BlackSeaCom.2019.8812820","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2019.8812820","url":null,"abstract":"Providing information in smart cities is possible in various ways. Digital signage is one of such options. However, personalization and contextualization of digital signage is complicated due to both technological and legislative reasons. When providing contextual information to a group of users, consideration of preferences and interests of users is complicated by a number of additional problems, most of which are related to identifying preferences/interests common to this group of users, as well as to their confidentiality. At the moment, such solutions do not exist. The paper presents a methodology of building a personalized digital signage system taking into account confidentiality and using tacit feedback to clarify the information provided, as well as information about users.","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124304003","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 : 2019-06-01DOI: 10.1109/BlackSeaCom.2019.8812824
A. Belogaev, E. Khorov, A. Krasilov, D. Shmelkin, Suwen Tang
Ultra reliable low latency communications (URLLC) is one of the most promising and demanding services in 5G systems. This service requires very low latency of less than 1 − 10 ms and very high transmission reliability: the acceptable packet loss ratio is about 10−5. To satisfy such strict requirements, many issues shall be solved. This paper focuses on the link adaptation problem, i.e., the selection of a modulation and coding scheme (MCS) for transmission based on the received channel quality indicator (CQI) reports. On the one hand, link adaptation should select a robust MCS to provide high reliability. On the other hand, it should select the highest possible MCS to reduce channel resource consumption. The paper shows that even for one URLLC user, link adaptation is still a challenging problem, especially in highly-variant channels. To solve this problem, a conservative link adaptation algorithm is designed. The algorithm estimates the strongest channel degradation at the time moment of the actual packet transmission and selects an MCS taking into account the worst degradation. The obtained results show that the proposed algorithm is efficient in terms of both the packet loss ratio and the channel resource consumption.
{"title":"Conservative Link Adaptation for Ultra Reliable Low Latency Communications","authors":"A. Belogaev, E. Khorov, A. Krasilov, D. Shmelkin, Suwen Tang","doi":"10.1109/BlackSeaCom.2019.8812824","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2019.8812824","url":null,"abstract":"Ultra reliable low latency communications (URLLC) is one of the most promising and demanding services in 5G systems. This service requires very low latency of less than 1 − 10 ms and very high transmission reliability: the acceptable packet loss ratio is about 10−5. To satisfy such strict requirements, many issues shall be solved. This paper focuses on the link adaptation problem, i.e., the selection of a modulation and coding scheme (MCS) for transmission based on the received channel quality indicator (CQI) reports. On the one hand, link adaptation should select a robust MCS to provide high reliability. On the other hand, it should select the highest possible MCS to reduce channel resource consumption. The paper shows that even for one URLLC user, link adaptation is still a challenging problem, especially in highly-variant channels. To solve this problem, a conservative link adaptation algorithm is designed. The algorithm estimates the strongest channel degradation at the time moment of the actual packet transmission and selects an MCS taking into account the worst degradation. The obtained results show that the proposed algorithm is efficient in terms of both the packet loss ratio and the channel resource consumption.","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122261594","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 : 2019-06-01DOI: 10.1109/BlackSeaCom.2019.8812782
Kamila Ragimova, Vyacheslav Loginov, E. Khorov
To design efficient resource allocation algorithms that satisfy users’ quality of service requirements, it is necessary to know or correctly estimate the traffic characteristics. In recent years, the share of video streams in the overall traffic has reached 70% and continues to grow. Most of this type of traffic is generated by popular video hosting services, such as YouTube, NetFlix, and others, which use the Dynamic Adaptive Streaming over HTTP technology. This paper discusses the results of a study on the properties the most popular videos on YouTube, the world’s largest video hosting service. In addition, it is shown how traffic parameters depend on the application used to watched Youtube videos and operating systems of PCs and mobile devices.
{"title":"Analysis of YouTube DASH Traffic","authors":"Kamila Ragimova, Vyacheslav Loginov, E. Khorov","doi":"10.1109/BlackSeaCom.2019.8812782","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2019.8812782","url":null,"abstract":"To design efficient resource allocation algorithms that satisfy users’ quality of service requirements, it is necessary to know or correctly estimate the traffic characteristics. In recent years, the share of video streams in the overall traffic has reached 70% and continues to grow. Most of this type of traffic is generated by popular video hosting services, such as YouTube, NetFlix, and others, which use the Dynamic Adaptive Streaming over HTTP technology. This paper discusses the results of a study on the properties the most popular videos on YouTube, the world’s largest video hosting service. In addition, it is shown how traffic parameters depend on the application used to watched Youtube videos and operating systems of PCs and mobile devices.","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132851826","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 : 2019-06-01DOI: 10.1109/BlackSeaCom.2019.8812809
R. Beniwal, K. Nikolova, G. Iliev
The communication world will be revolutionized with the advent of Internet of Things (IoT). The major challenge in IoT vision is to integrate to Wireless Sensor Network (WSN) to the Internet world. The communication protocols and IPv6 addressing method adapted in IoT require modification to match the WSN scenario. The standard name IPv6 over Low power Personal Area Network has been adapted for such type of mechanism. The performance analysis of MMSPEED routing algorithm’s adapted in 6LoWPAN network has been shown in this paper. The experimental validation results have been presented as compared with SPEED and HiLoW protocols. Throughput and routing overhead of the protocols in 6LoWPAN scenario are also presented. The simulations have been done in NS-3.
随着物联网(IoT)的出现，通信世界将发生革命性的变化。物联网愿景的主要挑战是将无线传感器网络(WSN)集成到互联网世界。物联网中采用的通信协议和IPv6寻址方法需要修改以匹配WSN场景。标准名称IPv6 over Low power Personal Area Network已经适应了这种类型的机制。本文对适用于6LoWPAN网络的MMSPEED路由算法进行了性能分析。实验验证结果与SPEED和HiLoW协议进行了比较。给出了6LoWPAN场景下各协议的吞吐量和路由开销。模拟已经在ns3中完成。
{"title":"Performance Analysis of MM-SPEED Routing Protocol Implemented in 6LoWPAN Environment","authors":"R. Beniwal, K. Nikolova, G. Iliev","doi":"10.1109/BlackSeaCom.2019.8812809","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2019.8812809","url":null,"abstract":"The communication world will be revolutionized with the advent of Internet of Things (IoT). The major challenge in IoT vision is to integrate to Wireless Sensor Network (WSN) to the Internet world. The communication protocols and IPv6 addressing method adapted in IoT require modification to match the WSN scenario. The standard name IPv6 over Low power Personal Area Network has been adapted for such type of mechanism. The performance analysis of MMSPEED routing algorithm’s adapted in 6LoWPAN network has been shown in this paper. The experimental validation results have been presented as compared with SPEED and HiLoW protocols. Throughput and routing overhead of the protocols in 6LoWPAN scenario are also presented. The simulations have been done in NS-3.","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130542517","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 : 2019-06-01DOI: 10.1109/BlackSeaCom.2019.8812778
L. Mucchi, Francesca Nizzi, T. Pecorella, R. Fantacci, Flavio Esposito
Physical-layer security (PLS) has raised the attention of the research community in recent years, particularly for Internet of things (IoT) applications. Despite the use of classical cryptography, PLS provides security at physical layer, regardless of the computational power owned by the attacker. The investigations on PLS are numerous in the literature, but one main issue seems to be kept apart: how to measure the benefit that PLS can bring to cryptography? This paper tries to answer this question with an initial performance analysis of PLS in conjunction with typical cryptography of wireless communication protocols. Our results indicate that PLS can help cryptography to harden the attacker job in real operative scenario: PLS can increase the detection errors at the attacker’s receiver, leading to inability to recover the cipher key, even if the plaintext is known.
{"title":"Benefits of Physical Layer Security to Cryptography: Tradeoff and Applications","authors":"L. Mucchi, Francesca Nizzi, T. Pecorella, R. Fantacci, Flavio Esposito","doi":"10.1109/BlackSeaCom.2019.8812778","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2019.8812778","url":null,"abstract":"Physical-layer security (PLS) has raised the attention of the research community in recent years, particularly for Internet of things (IoT) applications. Despite the use of classical cryptography, PLS provides security at physical layer, regardless of the computational power owned by the attacker. The investigations on PLS are numerous in the literature, but one main issue seems to be kept apart: how to measure the benefit that PLS can bring to cryptography? This paper tries to answer this question with an initial performance analysis of PLS in conjunction with typical cryptography of wireless communication protocols. Our results indicate that PLS can help cryptography to harden the attacker job in real operative scenario: PLS can increase the detection errors at the attacker’s receiver, leading to inability to recover the cipher key, even if the plaintext is known.","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"17 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124695653","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 : 2019-06-01DOI: 10.1109/blackseacom.2019.8812866
{"title":"BlackSeaCom 2019 Welcome Message from the General Chairs","authors":"","doi":"10.1109/blackseacom.2019.8812866","DOIUrl":"https://doi.org/10.1109/blackseacom.2019.8812866","url":null,"abstract":"","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125448564","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 : 2019-06-01DOI: 10.1109/BlackSeaCom.2019.8812787
E. Khorov, A. Kiryanov, A. Krotov
During the last decade, the number of devices connected to the Internet by Wi-Fi has grown significantly. A high density of both the client devices and the hot spots posed new challenges related to providing the desired quality of service in the current and emerging scenarios. To cope with the negative effects caused by network densification, modern Wi-Fi is becoming more and more centralized. To improve network efficiency, today many new Wi-Fi deployments are under control of management systems that optimize network parameters in a centralized manner. In the paper, for such a cloud management system, we develop an algorithm which aims at maximizing energy efficiency and also keeps fairness among clients. For that, we design an objective function and solve an optimization problem using the branch and bound approach. To evaluate the efficiency of the developed solution, we implement it in the NS-3 simulator and compare with existing solutions and legacy behavior.
{"title":"Cloud-based Management of Energy-Efficient Dense IEEE 802.11ax Networks","authors":"E. Khorov, A. Kiryanov, A. Krotov","doi":"10.1109/BlackSeaCom.2019.8812787","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2019.8812787","url":null,"abstract":"During the last decade, the number of devices connected to the Internet by Wi-Fi has grown significantly. A high density of both the client devices and the hot spots posed new challenges related to providing the desired quality of service in the current and emerging scenarios. To cope with the negative effects caused by network densification, modern Wi-Fi is becoming more and more centralized. To improve network efficiency, today many new Wi-Fi deployments are under control of management systems that optimize network parameters in a centralized manner. In the paper, for such a cloud management system, we develop an algorithm which aims at maximizing energy efficiency and also keeps fairness among clients. For that, we design an objective function and solve an optimization problem using the branch and bound approach. To evaluate the efficiency of the developed solution, we implement it in the NS-3 simulator and compare with existing solutions and legacy behavior.","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130185970","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 : 2019-06-01DOI: 10.1109/BlackSeaCom.2019.8812812
Z. Sayed, Y. Gadallah
Providing communication services connectivity in areas out of reach of the cellular infrastructure is a very active area of research. This connectivity is particularly needed in case of deploying machine type communication devices (MTCDs) for critical purposes such as homeland security. In such applications, MTCDs may be deployed in areas that are hard to reach through regular communications infrastructure while the collected data are timely critical. Drone-supported communications constitute a new trend in complementing the reach of the terrestrial communication infrastructure. In this study, drones are used as complementary base stations to provide real-time communication services to gather critical data out of a group of MTCDs that are sparsely deployed in a marine environment. Therefore, the drone movements among the different MTCDs are to be optimized to minimize data deadline missing. We therefore compare between an ant colony-based technique that aims at optimizing the drone movements among the different MTCDs to achieve this goal, with a genetic algorithm based one. We present the results of several simulation experiments that validate the different performance aspects of both techniques.
{"title":"Drone Base Station Trajectory Planning for Optimal Resource Scheduling in LTE Sparse M2M Networks","authors":"Z. Sayed, Y. Gadallah","doi":"10.1109/BlackSeaCom.2019.8812812","DOIUrl":"https://doi.org/10.1109/BlackSeaCom.2019.8812812","url":null,"abstract":"Providing communication services connectivity in areas out of reach of the cellular infrastructure is a very active area of research. This connectivity is particularly needed in case of deploying machine type communication devices (MTCDs) for critical purposes such as homeland security. In such applications, MTCDs may be deployed in areas that are hard to reach through regular communications infrastructure while the collected data are timely critical. Drone-supported communications constitute a new trend in complementing the reach of the terrestrial communication infrastructure. In this study, drones are used as complementary base stations to provide real-time communication services to gather critical data out of a group of MTCDs that are sparsely deployed in a marine environment. Therefore, the drone movements among the different MTCDs are to be optimized to minimize data deadline missing. We therefore compare between an ant colony-based technique that aims at optimizing the drone movements among the different MTCDs to achieve this goal, with a genetic algorithm based one. We present the results of several simulation experiments that validate the different performance aspects of both techniques.","PeriodicalId":359145,"journal":{"name":"2019 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127534262","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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