Pub Date : 2019-07-01DOI: 10.1109/LANMAN.2019.8846977
Yudong Yang, Yuming Jiang, V. Misra, D. Rubenstein
WiFi is the dominant means for home Internet access, yet is frequently a performance bottleneck. Without reliable, satisfactory performance at the last hop, end-to-end quality of service (QoS) efforts will fail. Three major reasons for WiFi bottlenecking performance are its: 1) inherent wireless channel characteristics, 2) approach to access control of the shared broadcast channel, and 3) impact on transport layer protocols, such as TCP, that operate end-to-end, and over-react to the loss or delay caused by the single WiFi link. In this paper, we leverage the philosophy of centralization in modern networking and present our cross layer design to address the problem. Specifically, we introduce centralized control at the point of entry/egress into the WiFi network. Based on network conditions measured from buffer sizes, airtime and throughput, flows are scheduled to the optimal utility. Unlike most existing WiFi QoS approaches, our design only relies on transparent modifications, requiring no changes to the network (including link layer) protocols, applications, or user intervention. Through extensive experimental investigation, we show that our design significantly enhances the reliability and predictability of WiFi performance, providing a “virtual wire”-like link to the targeted application.
{"title":"Virtual Wires: Rethinking WiFi networks","authors":"Yudong Yang, Yuming Jiang, V. Misra, D. Rubenstein","doi":"10.1109/LANMAN.2019.8846977","DOIUrl":"https://doi.org/10.1109/LANMAN.2019.8846977","url":null,"abstract":"WiFi is the dominant means for home Internet access, yet is frequently a performance bottleneck. Without reliable, satisfactory performance at the last hop, end-to-end quality of service (QoS) efforts will fail. Three major reasons for WiFi bottlenecking performance are its: 1) inherent wireless channel characteristics, 2) approach to access control of the shared broadcast channel, and 3) impact on transport layer protocols, such as TCP, that operate end-to-end, and over-react to the loss or delay caused by the single WiFi link. In this paper, we leverage the philosophy of centralization in modern networking and present our cross layer design to address the problem. Specifically, we introduce centralized control at the point of entry/egress into the WiFi network. Based on network conditions measured from buffer sizes, airtime and throughput, flows are scheduled to the optimal utility. Unlike most existing WiFi QoS approaches, our design only relies on transparent modifications, requiring no changes to the network (including link layer) protocols, applications, or user intervention. Through extensive experimental investigation, we show that our design significantly enhances the reliability and predictability of WiFi performance, providing a “virtual wire”-like link to the targeted application.","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125671552","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 : 2019-07-01DOI: 10.1109/LANMAN.2019.8847137
M. Bezunartea, Roald Van Glabbeek, An Braeken, J. Tiberghien, K. Steenhaut
We propose an adaptation of the well-known Time Slotted Channel Hopping (TSCH) Medium Access Control (MAC) protocol, which was initially specified for IEEE 802.15.4 based networks, for operation over the LoRa PHY layer. Thanks to its deterministic nature, multiple concurrent communications can be handled, while reducing channel collision and ensuring reliability in a power-efficient manner. The proposed solution was implemented in the Contiki-NG operating system and tested on real motes.
{"title":"Towards Energy Efficient LoRa Multihop Networks","authors":"M. Bezunartea, Roald Van Glabbeek, An Braeken, J. Tiberghien, K. Steenhaut","doi":"10.1109/LANMAN.2019.8847137","DOIUrl":"https://doi.org/10.1109/LANMAN.2019.8847137","url":null,"abstract":"We propose an adaptation of the well-known Time Slotted Channel Hopping (TSCH) Medium Access Control (MAC) protocol, which was initially specified for IEEE 802.15.4 based networks, for operation over the LoRa PHY layer. Thanks to its deterministic nature, multiple concurrent communications can be handled, while reducing channel collision and ensuring reliability in a power-efficient manner. The proposed solution was implemented in the Contiki-NG operating system and tested on real motes.","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121456606","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 : 2019-07-01DOI: 10.1109/LANMAN.2019.8847113
Francesca Soro, I. Drago, Martino Trevisan, M. Mellia, J. Ceron, J. J. Santanna
Darknets are sets of IP addresses that are advertised but do not host any client or server. By passively recording the incoming packets, they assist network monitoring activities. Since packets they receive are unsolicited by definition, darknets help to spot misconfigurations as well as important security events, such as the appearance and spread of botnets, DDoS attacks using spoofed IP address, etc. A number of organizations worldwide deploys darknets, ranging from a few dozens of IP addresses to large /8 networks. We here investigate how similar is the visibility of different darknets. By relying on traffic from three darknets deployed in different contintents, we evaluate their exposure in terms of observed events given their allocated IP addresses. The latter is particularly relevant considering the shortage of IPv4 addresses on the Internet. Our results suggest that some well-known facts about darknet visibility seem invariant across deployments, such as the most commonly contacted ports. However, size and location matter. We find significant differences in the observed traffic from darknets deployed in different IP ranges as well as according to the size of the IP range allocated for the monitoring.
{"title":"Are Darknets All The Same? On Darknet Visibility for Security Monitoring","authors":"Francesca Soro, I. Drago, Martino Trevisan, M. Mellia, J. Ceron, J. J. Santanna","doi":"10.1109/LANMAN.2019.8847113","DOIUrl":"https://doi.org/10.1109/LANMAN.2019.8847113","url":null,"abstract":"Darknets are sets of IP addresses that are advertised but do not host any client or server. By passively recording the incoming packets, they assist network monitoring activities. Since packets they receive are unsolicited by definition, darknets help to spot misconfigurations as well as important security events, such as the appearance and spread of botnets, DDoS attacks using spoofed IP address, etc. A number of organizations worldwide deploys darknets, ranging from a few dozens of IP addresses to large /8 networks. We here investigate how similar is the visibility of different darknets. By relying on traffic from three darknets deployed in different contintents, we evaluate their exposure in terms of observed events given their allocated IP addresses. The latter is particularly relevant considering the shortage of IPv4 addresses on the Internet. Our results suggest that some well-known facts about darknet visibility seem invariant across deployments, such as the most commonly contacted ports. However, size and location matter. We find significant differences in the observed traffic from darknets deployed in different IP ranges as well as according to the size of the IP range allocated for the monitoring.","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130148141","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 : 2019-07-01DOI: 10.1109/lanman.2019.8847018
{"title":"LANMAN 2019 TOC","authors":"","doi":"10.1109/lanman.2019.8847018","DOIUrl":"https://doi.org/10.1109/lanman.2019.8847018","url":null,"abstract":"","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128897479","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 : 2019-07-01DOI: 10.1109/LANMAN.2019.8847130
N. Makris, Virgilios Passas, Christos Nanis, T. Korakis
Multiple-access Edge Computing (MEC) has been proposed as a means to minimize the user to service path latency, by deploying and operating datacenter resources close to the network edge. The introduction of 5G mobile network services, and their provisioning through disaggregated base stations complying with the Cloud-RAN paradigm, allows the redefinition of the traditional Edge Computing by offering deployment of services even closer to the network access edge. In this work, we leverage a disaggregated heterogeneous 5G infrastructure, compliant with the 5G New Radio (NR) specifications, and present a scheme for placing the services even closer to the Edge, close to the concept of fog computing. We develop a scheme for the OpenAirInterface platform that allows services to be executed close or over the machines hosting the radio services for the network access. By exploiting features for integrating heterogeneous radio resources in the cell, we are able to create a controller interface for selecting the optimal radio access technology used to serve each user of the network from the MEC service perspective. We evaluate our solution in a real testbed setup, and measure performance related indicators for our solution by using adaptive video streaming. Our results illustrate up to 80% better video qualities delivered to the end user when appropriately selecting the access technology.
{"title":"On Minimizing Service Access Latency: Employing MEC on the Fronthaul of Heterogeneous 5G Architectures","authors":"N. Makris, Virgilios Passas, Christos Nanis, T. Korakis","doi":"10.1109/LANMAN.2019.8847130","DOIUrl":"https://doi.org/10.1109/LANMAN.2019.8847130","url":null,"abstract":"Multiple-access Edge Computing (MEC) has been proposed as a means to minimize the user to service path latency, by deploying and operating datacenter resources close to the network edge. The introduction of 5G mobile network services, and their provisioning through disaggregated base stations complying with the Cloud-RAN paradigm, allows the redefinition of the traditional Edge Computing by offering deployment of services even closer to the network access edge. In this work, we leverage a disaggregated heterogeneous 5G infrastructure, compliant with the 5G New Radio (NR) specifications, and present a scheme for placing the services even closer to the Edge, close to the concept of fog computing. We develop a scheme for the OpenAirInterface platform that allows services to be executed close or over the machines hosting the radio services for the network access. By exploiting features for integrating heterogeneous radio resources in the cell, we are able to create a controller interface for selecting the optimal radio access technology used to serve each user of the network from the MEC service perspective. We evaluate our solution in a real testbed setup, and measure performance related indicators for our solution by using adaptive video streaming. Our results illustrate up to 80% better video qualities delivered to the end user when appropriately selecting the access technology.","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134098932","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 : 2019-07-01DOI: 10.1109/LANMAN.2019.8846988
Steffen Thielemans, Benjamin Sartori, An Braeken, K. Steenhaut
A major goal of the H2020 Inter-IoT project is to provide a framework for seamless integration of different Internet of Things (IoT) platforms. To allow the Inter-IoT user to interact with those platforms, which feature their own syntax and Application Programming Interfaces (APIs), so called bridges are designed and implemented. For ensuring interoperability, semantics play a key role. The ontologies used by the different platforms need to be aligned with a central ontology. We present the features supported by Inter-IoT’s Inter-MiddleWare layer and discuss the operation of a bridge towards a oneM2M based platform.
{"title":"Integration of oneM2M in Inter-IoT’s platform of platforms","authors":"Steffen Thielemans, Benjamin Sartori, An Braeken, K. Steenhaut","doi":"10.1109/LANMAN.2019.8846988","DOIUrl":"https://doi.org/10.1109/LANMAN.2019.8846988","url":null,"abstract":"A major goal of the H2020 Inter-IoT project is to provide a framework for seamless integration of different Internet of Things (IoT) platforms. To allow the Inter-IoT user to interact with those platforms, which feature their own syntax and Application Programming Interfaces (APIs), so called bridges are designed and implemented. For ensuring interoperability, semantics play a key role. The ontologies used by the different platforms need to be aligned with a central ontology. We present the features supported by Inter-IoT’s Inter-MiddleWare layer and discuss the operation of a bridge towards a oneM2M based platform.","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132757667","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 : 2019-07-01DOI: 10.1109/LANMAN.2019.8846996
Koki Goto, Yusaku Hayamizu, M. Bandai, M. Yamamoto
In Adaptive Bit Rate (ABR) utilized in MPEG-DASH (MPEG Dynamic Adaptive Streaming over HTTP), there have been proposed three representative algorithms, rate-based, buffer-based and hybrid-based ones. In the information centric networks, which have been widely studied as a network architecture for efficient content distribution including video streaming, routers are generally equipped with cache storage. When some segments of a required content is occasionally downloaded from cache storage in a router, content download from a router might be faster than segment retrieval from the original content server. This inaccurate throughput estimation might lead to inappropriate bitrate selection of ABR algorithm running on the user’s application and significant degradation of QoE (Quality of Experience) performance. In this paper, from the viewpoint of QoE, we evaluate the influence of in-network caches on three types of ABR algorithm in video streaming.
在MPEG- dash (MPEG Dynamic Adaptive Streaming over HTTP)中使用的自适应比特率(ABR)算法中，提出了基于速率的、基于缓冲区的和基于混合的三种代表性算法。信息中心网络作为一种高效内容分发(包括视频流)的网络架构已被广泛研究，路由器通常配备缓存存储。当偶尔从路由器的缓存存储中下载所需内容的某些片段时，从路由器下载内容可能比从原始内容服务器检索片段要快。这种不准确的吞吐量估计可能会导致在用户应用程序上运行的ABR算法的比特率选择不适当，并且会显著降低QoE(体验质量)性能。本文从QoE的角度，评估了网络内缓存对视频流中三种ABR算法的影响。
{"title":"QoE Performance of Adaptive Video Streaming in Information Centric Networks","authors":"Koki Goto, Yusaku Hayamizu, M. Bandai, M. Yamamoto","doi":"10.1109/LANMAN.2019.8846996","DOIUrl":"https://doi.org/10.1109/LANMAN.2019.8846996","url":null,"abstract":"In Adaptive Bit Rate (ABR) utilized in MPEG-DASH (MPEG Dynamic Adaptive Streaming over HTTP), there have been proposed three representative algorithms, rate-based, buffer-based and hybrid-based ones. In the information centric networks, which have been widely studied as a network architecture for efficient content distribution including video streaming, routers are generally equipped with cache storage. When some segments of a required content is occasionally downloaded from cache storage in a router, content download from a router might be faster than segment retrieval from the original content server. This inaccurate throughput estimation might lead to inappropriate bitrate selection of ABR algorithm running on the user’s application and significant degradation of QoE (Quality of Experience) performance. In this paper, from the viewpoint of QoE, we evaluate the influence of in-network caches on three types of ABR algorithm in video streaming.","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"582 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134303478","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 : 2019-07-01DOI: 10.1109/LANMAN.2019.8846975
Y. Kurihara, Y. Koizumi, T. Hasegawa
This paper addresses edge computing for location-based service where location data is obtained by Internet of Things devices. A key motivation of the paper is to propose a location-based routing/forwarding framework where a computation request of location data is forwarded to an appropriated edge router. The word “appropriate” means that time of retrieving location data as an argument of the computation is minimized. As the result, computing time is minimized.
{"title":"Computing Node Selection for Location-based Service in NDN Networks","authors":"Y. Kurihara, Y. Koizumi, T. Hasegawa","doi":"10.1109/LANMAN.2019.8846975","DOIUrl":"https://doi.org/10.1109/LANMAN.2019.8846975","url":null,"abstract":"This paper addresses edge computing for location-based service where location data is obtained by Internet of Things devices. A key motivation of the paper is to propose a location-based routing/forwarding framework where a computation request of location data is forwarded to an appropriated edge router. The word “appropriate” means that time of retrieving location data as an argument of the computation is minimized. As the result, computing time is minimized.","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131255219","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 : 2019-07-01DOI: 10.1109/LANMAN.2019.8846993
I. Ivanciu, Liliana Ivanciu, Daniel Zinca, V. Dobrota
Public healthcare is a major priority in today’s society. With the introduction of wearable devices, monitoring, detecting and preventing health conditions has become cheaper and easier. On the down side, transmitting and storing all this sensitive data poses new challenges. We propose an original solution for securing the transmission of data gathered by sensors in a Wireless Body Area Network using the Electrocardiogram signal and Named Data Networks. Our contribution is two-fold: first of all, we make use of the inherent features of such networks to securely transmit sensitive, health-related data (of a regular patient or a driver) to the cloud and then disseminate it to interested parties such as physicians. Second, our approach exploits the properties of the Electrocardiogram signal (robustness to attacks, universality and liveness detection) to encrypt this data and provide a simple and fast authentication mechanism between the devices in the Wireless Body Area Network.
{"title":"Securing Health-Related Data Transmission Using ECG and Named Data Networks","authors":"I. Ivanciu, Liliana Ivanciu, Daniel Zinca, V. Dobrota","doi":"10.1109/LANMAN.2019.8846993","DOIUrl":"https://doi.org/10.1109/LANMAN.2019.8846993","url":null,"abstract":"Public healthcare is a major priority in today’s society. With the introduction of wearable devices, monitoring, detecting and preventing health conditions has become cheaper and easier. On the down side, transmitting and storing all this sensitive data poses new challenges. We propose an original solution for securing the transmission of data gathered by sensors in a Wireless Body Area Network using the Electrocardiogram signal and Named Data Networks. Our contribution is two-fold: first of all, we make use of the inherent features of such networks to securely transmit sensitive, health-related data (of a regular patient or a driver) to the cloud and then disseminate it to interested parties such as physicians. Second, our approach exploits the properties of the Electrocardiogram signal (robustness to attacks, universality and liveness detection) to encrypt this data and provide a simple and fast authentication mechanism between the devices in the Wireless Body Area Network.","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127650266","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 : 2019-07-01DOI: 10.1109/LANMAN.2019.8847134
Cong Wang, M. Zink
Video streaming is the most popular application on today’s Internet. Millions of people around the globe access video contents using various end user devices, such as smart phones, tablets, laptops, and TVs. To meet the requirements of different end user devices and variable network conditions, videos need to be encoded into different quality versions before delivery to the clients. Such large-scale encoding tasks consume significant amounts of energy. In this paper, we investigate to what extent the realtime video encoding clouds can be powered by renewable energy sources. We show that video encoding tasks are suitable for execution on clouds that are powered by a combination of renewable and grid energy sources. With the use of our power management policies, grid energy usage can be reduced by 73–83%, which leads to electricity cost reductions of 14–28% compared to unlimited non-renewable power.
{"title":"Sustainable Cloud Encoding for Adaptive Bitrate Streaming over CDNs","authors":"Cong Wang, M. Zink","doi":"10.1109/LANMAN.2019.8847134","DOIUrl":"https://doi.org/10.1109/LANMAN.2019.8847134","url":null,"abstract":"Video streaming is the most popular application on today’s Internet. Millions of people around the globe access video contents using various end user devices, such as smart phones, tablets, laptops, and TVs. To meet the requirements of different end user devices and variable network conditions, videos need to be encoded into different quality versions before delivery to the clients. Such large-scale encoding tasks consume significant amounts of energy. In this paper, we investigate to what extent the realtime video encoding clouds can be powered by renewable energy sources. We show that video encoding tasks are suitable for execution on clouds that are powered by a combination of renewable and grid energy sources. With the use of our power management policies, grid energy usage can be reduced by 73–83%, which leads to electricity cost reductions of 14–28% compared to unlimited non-renewable power.","PeriodicalId":214356,"journal":{"name":"2019 IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130933873","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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