Pub Date : 2015-09-28DOI: 10.1109/APNOMS.2015.7275345
Huigwang Je, Dongwoo Kwon, Hongtaek Ju
The hierarchical network structure is proposed as a solution to the problem of decreased network performance for large-scale multimedia delivery in a single wireless LAN environment. However, the network structure on the Android OS is used for media streaming service; the role of the source device is important because a group owner delay causes a performance problem in which streaming data transmission to all Wi-Fi direct network groups creates a bottleneck. For a solution to these problems, we propose the media stream relay engine architecture and describe sequence diagrams for the development of a relay engine on the Android OS.
{"title":"Design of a media stream relay engine on the Android OS","authors":"Huigwang Je, Dongwoo Kwon, Hongtaek Ju","doi":"10.1109/APNOMS.2015.7275345","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275345","url":null,"abstract":"The hierarchical network structure is proposed as a solution to the problem of decreased network performance for large-scale multimedia delivery in a single wireless LAN environment. However, the network structure on the Android OS is used for media streaming service; the role of the source device is important because a group owner delay causes a performance problem in which streaming data transmission to all Wi-Fi direct network groups creates a bottleneck. For a solution to these problems, we propose the media stream relay engine architecture and describe sequence diagrams for the development of a relay engine on the Android OS.","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114886925","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 : 2015-09-28DOI: 10.1109/APNOMS.2015.7275400
YooJin Kwon, Myung-Sup Kim, Yong-hun Lim, Jong-in Lim
Smart grid is an electricity network to monitor and control all its physical environments of electricity infrastructure in a fully automated way. As the importance of reliable energy utility infrastructure is growing, various security countermeasures to protect power system from security threats have been suggested, whereas there were less consideration on security by design, from the bottom system modeling level. Thus, this paper first highlights the international security standard on network and system management (NSM) requirements suggested from International Electronical Committee (IEC). Then this paper proposes significance of security by design, especially the security object modeling as the most important factor in smart grid environment. In our approach, we propose a common NSM objects for IEC-61850 protocol based substation automation environment. Finally, we present the setup procedures to implement and test NSM objects for IEC 61850-based digital substation in Korean environment.
{"title":"Network and system management object modeling for smart grid infrastructure","authors":"YooJin Kwon, Myung-Sup Kim, Yong-hun Lim, Jong-in Lim","doi":"10.1109/APNOMS.2015.7275400","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275400","url":null,"abstract":"Smart grid is an electricity network to monitor and control all its physical environments of electricity infrastructure in a fully automated way. As the importance of reliable energy utility infrastructure is growing, various security countermeasures to protect power system from security threats have been suggested, whereas there were less consideration on security by design, from the bottom system modeling level. Thus, this paper first highlights the international security standard on network and system management (NSM) requirements suggested from International Electronical Committee (IEC). Then this paper proposes significance of security by design, especially the security object modeling as the most important factor in smart grid environment. In our approach, we propose a common NSM objects for IEC-61850 protocol based substation automation environment. Finally, we present the setup procedures to implement and test NSM objects for IEC 61850-based digital substation in Korean environment.","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131757867","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 : 2015-09-28DOI: 10.1109/APNOMS.2015.7275373
Sung-Min Kim, Young-Hoon Goo, Myung-Sup Kim, Soo-Gil Choi, Mi-Jung Choi
The SSL/TLS, one of the most popular encryption protocol, was developed as a solution of various network security problem while the network traffic has become complex and diverse. But the SSL/TLS traffic has been identified as its protocol name, not its used services, which is required for the effective network traffic management. This paper proposes a new method to generate service signatures automatically from SSL/TLS payload data and to classify network traffic in accordance with their application services. We utilize the certificate publication information field in the certificate exchanging record of SSL/TLS traffic for the service signatures, which occurs when SSL/TLS performs Handshaking before encrypt transmission. We proved the performance and feasibility of the proposed method by experimental result that classify about 95% SSL/TLS traffic with about 90% accuracy for every SSL/TLS services.
{"title":"A method for service identification of SSL/TLS encrypted traffic with the relation of session ID and Server IP","authors":"Sung-Min Kim, Young-Hoon Goo, Myung-Sup Kim, Soo-Gil Choi, Mi-Jung Choi","doi":"10.1109/APNOMS.2015.7275373","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275373","url":null,"abstract":"The SSL/TLS, one of the most popular encryption protocol, was developed as a solution of various network security problem while the network traffic has become complex and diverse. But the SSL/TLS traffic has been identified as its protocol name, not its used services, which is required for the effective network traffic management. This paper proposes a new method to generate service signatures automatically from SSL/TLS payload data and to classify network traffic in accordance with their application services. We utilize the certificate publication information field in the certificate exchanging record of SSL/TLS traffic for the service signatures, which occurs when SSL/TLS performs Handshaking before encrypt transmission. We proved the performance and feasibility of the proposed method by experimental result that classify about 95% SSL/TLS traffic with about 90% accuracy for every SSL/TLS services.","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"21 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116780899","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 : 2015-09-28DOI: 10.1109/APNOMS.2015.7275349
Qinghong Zhong, Y. Wang, Luoming Meng, Ailing Xiao, Hongjing Zhang
In network virtualization environment, if a virtual network (VN) needs to be deployed across multiple infrastructure domains, a splitting scheme of the VN should be found. With the goal of minimizing embedding cost, the existing methods solve VN splitting by linear programing. However, since the VN splitting problem is NP-Hard, these methods will take a lot of computing time when the problem scale gets bigger. In this paper, a max-flow/min-cut theory based VN splitting mechanism is proposed. The proposed method first creates a binary tree of the InPs by system clustering method, based on which the multidomain VN splitting problem is decomposed into several two-domain VN splitting problems. Then the method transforms each two-domain splitting problem into a max-flow/min-cut problem, and solves it by the shortest augmenting path algorithm efficiently. Simulations show that the proposed mechanism can improve the efficiency of VN splitting steadily and save the embedding cost.
{"title":"A max-flow/min-cut theory based multi-domain virtual network splitting mechanism","authors":"Qinghong Zhong, Y. Wang, Luoming Meng, Ailing Xiao, Hongjing Zhang","doi":"10.1109/APNOMS.2015.7275349","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275349","url":null,"abstract":"In network virtualization environment, if a virtual network (VN) needs to be deployed across multiple infrastructure domains, a splitting scheme of the VN should be found. With the goal of minimizing embedding cost, the existing methods solve VN splitting by linear programing. However, since the VN splitting problem is NP-Hard, these methods will take a lot of computing time when the problem scale gets bigger. In this paper, a max-flow/min-cut theory based VN splitting mechanism is proposed. The proposed method first creates a binary tree of the InPs by system clustering method, based on which the multidomain VN splitting problem is decomposed into several two-domain VN splitting problems. Then the method transforms each two-domain splitting problem into a max-flow/min-cut problem, and solves it by the shortest augmenting path algorithm efficiently. Simulations show that the proposed mechanism can improve the efficiency of VN splitting steadily and save the embedding cost.","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130232804","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 : 2015-09-28DOI: 10.1109/APNOMS.2015.7275438
H. Huang, Po-Han Lee, Y. Tseng, Bo-Ting Lin, Wan-Hsun Hu
Since static pricing models (such as flat-rate or tiered-rate models) can not improve user utility for subscribers and ease network congestion for operators during peak time, Smart Data Pricing (SDP) has become an important incentive for mobile data markets. Paris Metro Pricing (PMP), which is a static pricing mode inspired by the pricing model for the Paris metro system, uses differentiated prices to motivate users to choose different train classes. Before choosing a class, people will consider their expected quality of service (QoS) versus the prices that they are willing to pay. Even though PMP can not guarantee the actual QoS during service time, a balance between users' utilities and operators' revenue is achieved. In this paper, we propose a dynamic PMP scheme, so-called DPMP, which determines the prices and capacities of different classes for the next 24 hours. The prices should optimize the revenues and utilities for operators and subscribers, respectively. Our simulation results show that DPMP can better balance those two factors and determine the appropriate log period for operators.
{"title":"An hourly day-ahead Paris Metro Pricing scheme for mobile data networks","authors":"H. Huang, Po-Han Lee, Y. Tseng, Bo-Ting Lin, Wan-Hsun Hu","doi":"10.1109/APNOMS.2015.7275438","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275438","url":null,"abstract":"Since static pricing models (such as flat-rate or tiered-rate models) can not improve user utility for subscribers and ease network congestion for operators during peak time, Smart Data Pricing (SDP) has become an important incentive for mobile data markets. Paris Metro Pricing (PMP), which is a static pricing mode inspired by the pricing model for the Paris metro system, uses differentiated prices to motivate users to choose different train classes. Before choosing a class, people will consider their expected quality of service (QoS) versus the prices that they are willing to pay. Even though PMP can not guarantee the actual QoS during service time, a balance between users' utilities and operators' revenue is achieved. In this paper, we propose a dynamic PMP scheme, so-called DPMP, which determines the prices and capacities of different classes for the next 24 hours. The prices should optimize the revenues and utilities for operators and subscribers, respectively. Our simulation results show that DPMP can better balance those two factors and determine the appropriate log period for operators.","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"564 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125400914","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 : 2015-09-28DOI: 10.1109/APNOMS.2015.7275380
Haneul Ko, Giwon Lee, Insun Jang, Sangheon Pack
Current evolved packet core (EPC) systems in LTE/LTE-A networks suffer from the exponentially increased mobile traffic and thus research on new EPC architectures is ongoing. In this paper, we introduce a virtualized EPC (vEPC) system where middlebox functions of the existing EPC systems are implemented in virtualized software modules and the virtualized software modules operate over selected physical service nodes. To minimize the impact of the increased transmission cost in vEPC, the optimal placement of middlebox functions is also investigated. Numerical results demonstrate that the proposed scheme can achieve lower packet transmission cost than the conventional one.
{"title":"Optimal middlebox function placement in virtualized evolved packet core systems","authors":"Haneul Ko, Giwon Lee, Insun Jang, Sangheon Pack","doi":"10.1109/APNOMS.2015.7275380","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275380","url":null,"abstract":"Current evolved packet core (EPC) systems in LTE/LTE-A networks suffer from the exponentially increased mobile traffic and thus research on new EPC architectures is ongoing. In this paper, we introduce a virtualized EPC (vEPC) system where middlebox functions of the existing EPC systems are implemented in virtualized software modules and the virtualized software modules operate over selected physical service nodes. To minimize the impact of the increased transmission cost in vEPC, the optimal placement of middlebox functions is also investigated. Numerical results demonstrate that the proposed scheme can achieve lower packet transmission cost than the conventional one.","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125019297","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 : 2015-09-28DOI: 10.1109/APNOMS.2015.7275429
K. Hirata, Kohei Ito, Y. Fukuchi, M. Muraguchi
This paper proposes a dynamic lightpath establishment scheme considering power consumption of multifiber all-optical networks. In all-optical networks, optical amplifiers consume much power to amplify a group of optical signals with different wavelengths. The proposed scheme provides an ingenious routing and wavelength assignment strategy which preferentially uses active optical amplifiers and avoids using inactive optical amplifiers. Furthermore, the proposed scheme avoids blocking of lightpath establishment due to depletion of wavelength resources. Through simulation experiments, we show that the proposed scheme efficiently reduces both blocking probability of lightpath establishment and power consumption of optical networks.
{"title":"Dynamic lightpath establishment for achieving low power all-optical networks","authors":"K. Hirata, Kohei Ito, Y. Fukuchi, M. Muraguchi","doi":"10.1109/APNOMS.2015.7275429","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275429","url":null,"abstract":"This paper proposes a dynamic lightpath establishment scheme considering power consumption of multifiber all-optical networks. In all-optical networks, optical amplifiers consume much power to amplify a group of optical signals with different wavelengths. The proposed scheme provides an ingenious routing and wavelength assignment strategy which preferentially uses active optical amplifiers and avoids using inactive optical amplifiers. Furthermore, the proposed scheme avoids blocking of lightpath establishment due to depletion of wavelength resources. Through simulation experiments, we show that the proposed scheme efficiently reduces both blocking probability of lightpath establishment and power consumption of optical networks.","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124488137","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 : 2015-09-28DOI: 10.1109/APNOMS.2015.7275447
O. Kim, Nguyen Dang Tri, Vandung Nguyen, Nguyen H. Tran, C. Hong
At the present, the traffic is really in a mess when the number of vehicles is increasing rapidly. As a consequence, finding a parking space is remarkably difficult and expensive. Therefore, solving this problem has attracted the attention of both scientists and companies. Our study also focuses on solving parking problem to relieve the traffic congestion, reduce air pollution and enhance driving effectively. However, unlike other studies, we consider parking problem in the view of IoT. From this perspective, Fog Computing and Roadside Cloud are utilized to find a vacant spot. By utilizing this infrastructures, any parking space at many places can be shared. Then, we analyze and apply the matching theory to solve the parking problem. Accordingly, our proposal not only helps drivers finding an ideal available space but also brings the owners of these places profit. Simulation results demonstrate that the proposed approach is a reliable solution for the finding parking slot.
{"title":"A shared parking model in vehicular network using fog and cloud environment","authors":"O. Kim, Nguyen Dang Tri, Vandung Nguyen, Nguyen H. Tran, C. Hong","doi":"10.1109/APNOMS.2015.7275447","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275447","url":null,"abstract":"At the present, the traffic is really in a mess when the number of vehicles is increasing rapidly. As a consequence, finding a parking space is remarkably difficult and expensive. Therefore, solving this problem has attracted the attention of both scientists and companies. Our study also focuses on solving parking problem to relieve the traffic congestion, reduce air pollution and enhance driving effectively. However, unlike other studies, we consider parking problem in the view of IoT. From this perspective, Fog Computing and Roadside Cloud are utilized to find a vacant spot. By utilizing this infrastructures, any parking space at many places can be shared. Then, we analyze and apply the matching theory to solve the parking problem. Accordingly, our proposal not only helps drivers finding an ideal available space but also brings the owners of these places profit. Simulation results demonstrate that the proposed approach is a reliable solution for the finding parking slot.","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"252 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132842311","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 : 2015-09-28DOI: 10.1109/APNOMS.2015.7275405
Donghyuk Lee, Namje Park, Dooho Choi
The IVEF protocol developed by IALA is focused on the technical implementation. But, It does not contain the description of the information encryption for IVEF protocol data protection. The vessel traffic information is high sensitive information. So a necessary part of the absolute reliability of the information client and data security. This paper suggests the authentication protocol to increase the security of the VTS systems using the main certification server and IVEF.
{"title":"Inter-vessel traffic service data exchange format protocol security enhancement of user authentication scheme in mobile VTS middleware platform","authors":"Donghyuk Lee, Namje Park, Dooho Choi","doi":"10.1109/APNOMS.2015.7275405","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275405","url":null,"abstract":"The IVEF protocol developed by IALA is focused on the technical implementation. But, It does not contain the description of the information encryption for IVEF protocol data protection. The vessel traffic information is high sensitive information. So a necessary part of the absolute reliability of the information client and data security. This paper suggests the authentication protocol to increase the security of the VTS systems using the main certification server and IVEF.","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115798583","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 : 2015-09-28DOI: 10.1109/APNOMS.2015.7275413
Choongul Park, C. Hwang, Kitae Jeong
This Paper presents a telco's perspectives and experiences to design and implement open and flexible architecture for Transport SDN (T-SDN). We believe that this could be realized by adopting open source based SDN controllers because they already have widely accepted and referenced architecture with a rich ecosystem. Moreover, we could have further benefits from open source such as reducing time to deploy and saving cost to develop. Regarding transport domain, however, there are still some challenges for us to adopt open source controllers. That is, which open source is appropriate, how to seamlessly integrate with legacy system, and which features of open source controller are adequate in current environment are things like that. In this paper, we discuss these challenges in depth and give some directions from our Proof-of-Concept (PoC) experiences for developing T-SDN based on OpenDayLight (ODL).
{"title":"A telco's perspectives: Open and flexible transport SDN","authors":"Choongul Park, C. Hwang, Kitae Jeong","doi":"10.1109/APNOMS.2015.7275413","DOIUrl":"https://doi.org/10.1109/APNOMS.2015.7275413","url":null,"abstract":"This Paper presents a telco's perspectives and experiences to design and implement open and flexible architecture for Transport SDN (T-SDN). We believe that this could be realized by adopting open source based SDN controllers because they already have widely accepted and referenced architecture with a rich ecosystem. Moreover, we could have further benefits from open source such as reducing time to deploy and saving cost to develop. Regarding transport domain, however, there are still some challenges for us to adopt open source controllers. That is, which open source is appropriate, how to seamlessly integrate with legacy system, and which features of open source controller are adequate in current environment are things like that. In this paper, we discuss these challenges in depth and give some directions from our Proof-of-Concept (PoC) experiences for developing T-SDN based on OpenDayLight (ODL).","PeriodicalId":269263,"journal":{"name":"2015 17th Asia-Pacific Network Operations and Management Symposium (APNOMS)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125001708","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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