{"title":"Users and services in intelligent networks","authors":"E. Gelenbe","doi":"10.1007/11599593_3","DOIUrl":"https://doi.org/10.1007/11599593_3","url":null,"abstract":"","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126226260","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431684
Alberto E. García, K. Hackbarth, Roberto Ortiz Telematic
A specific objective of the EURO-NGI network is the development of a Macro-tool which provides a homogeneous environment for hosting and interrelation of the software tools developed by the research labs of the network. The development of such a software environment raises several coordination and integration issues. This paper proposes tool integration under a common user access interface as an optimal solution and proposes the Web interface as the most natural option. The paper explains several innovative aspects in the field of remote software tool execution, secure access, customized interfaces and sharing environments for simultaneous execution and exposure of the main aspects of a sharing environment for network planning tools, named WeBaSeRex and its application for tasks in the EURO-NGI network of excellence.
{"title":"Web-based service for remote execution: NGI network design application","authors":"Alberto E. García, K. Hackbarth, Roberto Ortiz Telematic","doi":"10.1109/NGI.2005.1431684","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431684","url":null,"abstract":"A specific objective of the EURO-NGI network is the development of a Macro-tool which provides a homogeneous environment for hosting and interrelation of the software tools developed by the research labs of the network. The development of such a software environment raises several coordination and integration issues. This paper proposes tool integration under a common user access interface as an optimal solution and proposes the Web interface as the most natural option. The paper explains several innovative aspects in the field of remote software tool execution, secure access, customized interfaces and sharing environments for simultaneous execution and exposure of the main aspects of a sharing environment for network planning tools, named WeBaSeRex and its application for tasks in the EURO-NGI network of excellence.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125282877","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431696
G. Kurup, Y. Sekercioglu, N. Mani
Source specific multicast (SSM) is the most promising and realistic group communication architecture on the Internet to date. Mobile IPv6 capability and pervasive wireless access will enable and further encourage personal electronic devices to rely on the Internet for communications. Consequently, we are likely to witness an increase of broadcast-like and peer-to-peer multimedia applications designed for mobile networks and devices. Multicast, especially the source specific multicast architecture, is an advantageous delivery mechanism for such applications in bandwidth constrained environments. Although SSM is an efficient and scalable architecture, there exists many issues to be resolved prior to successful large scale deployment. For example, the performance of SSM applications over mobile networks has not been well researched to date. In this paper, we present our analysis framework to investigate multicast listener discovery version 2 (MLDv2) characteristics. We want to determine the effects and results of tuning various parameters for group management made available by the IETF specification. Our eventual study aims to incorporate and analyse all the relevant protocols for SSM MIPv6 and provide a reference for IP engineers intending to deploy such services.
{"title":"Source specific multicast (SSM) group management analysis framework for the next generation mobile Internet","authors":"G. Kurup, Y. Sekercioglu, N. Mani","doi":"10.1109/NGI.2005.1431696","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431696","url":null,"abstract":"Source specific multicast (SSM) is the most promising and realistic group communication architecture on the Internet to date. Mobile IPv6 capability and pervasive wireless access will enable and further encourage personal electronic devices to rely on the Internet for communications. Consequently, we are likely to witness an increase of broadcast-like and peer-to-peer multimedia applications designed for mobile networks and devices. Multicast, especially the source specific multicast architecture, is an advantageous delivery mechanism for such applications in bandwidth constrained environments. Although SSM is an efficient and scalable architecture, there exists many issues to be resolved prior to successful large scale deployment. For example, the performance of SSM applications over mobile networks has not been well researched to date. In this paper, we present our analysis framework to investigate multicast listener discovery version 2 (MLDv2) characteristics. We want to determine the effects and results of tuning various parameters for group management made available by the IETF specification. Our eventual study aims to incorporate and analyse all the relevant protocols for SSM MIPv6 and provide a reference for IP engineers intending to deploy such services.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122018232","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431669
M. Pióro, M. Dzida, E. Kubilinskas, P. Nilsson
The rapid growth of traffic induced by Internet services makes the simple over-provisioning of resources not economical and hence imposes new requirements on the dimensioning methods. Therefore, the problem of network design with the objective of minimizing the cost and at the same time solving the tradeoff between maximizing the service data flows and providing fair treatment of all demands becomes more and more important. In this context, the so-called max-min fair (MMF) principle is widely considered to help finding reasonable bandwidth allocation schemes for competing demands. Roughly speaking, MMF assumes that the worst service performance is maximized, and then is the second worst performance, the third one, and so on, leading to a lexicographically maximized vector of sorted demand bandwidth allocations. It turns out that the MMF optimal solution cannot be approached in a standard way (i.e., as a mathematical programming problem) due to the necessity of lexicographic maximization of ordered quantities (bandwidth allocated to demands). Still, for convex models, it is possible to formulate effective sequential procedures for such lexicographic optimization. The purpose of the presented paper is three-fold. First, it discusses resolution algorithms for a generic MMF problem related to telecommunications network design. Second, it gives a survey of network design instances of the generic formulation, and illustrates the efficiency of the general algorithms in these particular cases. Finally, the paper discusses extensions of the formulated problems into more practical (unfortunately non-convex) cases, where the general for convex MMF problems approach fails.
{"title":"Applications of the max-min fairness principle in telecommunication network design","authors":"M. Pióro, M. Dzida, E. Kubilinskas, P. Nilsson","doi":"10.1109/NGI.2005.1431669","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431669","url":null,"abstract":"The rapid growth of traffic induced by Internet services makes the simple over-provisioning of resources not economical and hence imposes new requirements on the dimensioning methods. Therefore, the problem of network design with the objective of minimizing the cost and at the same time solving the tradeoff between maximizing the service data flows and providing fair treatment of all demands becomes more and more important. In this context, the so-called max-min fair (MMF) principle is widely considered to help finding reasonable bandwidth allocation schemes for competing demands. Roughly speaking, MMF assumes that the worst service performance is maximized, and then is the second worst performance, the third one, and so on, leading to a lexicographically maximized vector of sorted demand bandwidth allocations. It turns out that the MMF optimal solution cannot be approached in a standard way (i.e., as a mathematical programming problem) due to the necessity of lexicographic maximization of ordered quantities (bandwidth allocated to demands). Still, for convex models, it is possible to formulate effective sequential procedures for such lexicographic optimization. The purpose of the presented paper is three-fold. First, it discusses resolution algorithms for a generic MMF problem related to telecommunications network design. Second, it gives a survey of network design instances of the generic formulation, and illustrates the efficiency of the general algorithms in these particular cases. Finally, the paper discusses extensions of the formulated problems into more practical (unfortunately non-convex) cases, where the general for convex MMF problems approach fails.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121152303","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431641
A. Costa, M. J. Nicolau, A. Santos, V. Freitas
Many already in use applications require the provision of QoS services from the underlying network infra-structure. This is particularly true for multicast, since it involves many participants at very sparse locations usually aiming to receive or send multimedia real-time streams. One way to provide QoS is through routing, since QoS aware multicast routing protocols can find feasible multicast trees. In this paper an inter-domain QoS multicast routing protocol is presented, specifically designed for the hierarchical inter-domain scenario, where requirements like intra-domain independency and policy awareness should be met. Emphasis is given to the path probing mechanism used to connect new members to the multicast tree, stressing how it differs from others. Simulation results show that despite using a less aggressive and simplified probing mechanism-more suitable for inter-domain scenarios-the proposed routing strategy can build multicast trees with metrics similar to those build by more aggressive techniques, with considerable less effort.
{"title":"A new path probing strategy for inter-domain multicast routing","authors":"A. Costa, M. J. Nicolau, A. Santos, V. Freitas","doi":"10.1109/NGI.2005.1431641","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431641","url":null,"abstract":"Many already in use applications require the provision of QoS services from the underlying network infra-structure. This is particularly true for multicast, since it involves many participants at very sparse locations usually aiming to receive or send multimedia real-time streams. One way to provide QoS is through routing, since QoS aware multicast routing protocols can find feasible multicast trees. In this paper an inter-domain QoS multicast routing protocol is presented, specifically designed for the hierarchical inter-domain scenario, where requirements like intra-domain independency and policy awareness should be met. Emphasis is given to the path probing mechanism used to connect new members to the multicast tree, stressing how it differs from others. Simulation results show that despite using a less aggressive and simplified probing mechanism-more suitable for inter-domain scenarios-the proposed routing strategy can build multicast trees with metrics similar to those build by more aggressive techniques, with considerable less effort.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134148286","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431693
Lei Liang, Zhili Sun, D. He
All IPPM QoS parameter metrics are defined for end-to-end one-way measurement These metrics provide exact indicators of network layer quality in the pair communications. However, further attention should be put on the multiparty communications, which might use multicast routing protocols, e.g., the IP conferencing services, online gaming, online stock market and etc. To qualify the multiparty communications, the future QoS study and metrics are required to be defined. The purpose of this paper is to highlight the new QoS requirements of the multiparty communication services in terms of relative delay, relative jitter and relative packet loss. A set of parameter metrics is derived from the existing one-way metrics in IP performance metrics (IPPM) for the multiparty communications to present these new requirements. These parameter metrics are supposed to provide methods and rules for engineers to measure and judge the QoS of the multiparty communications.
{"title":"New parameters and metrics for multiparty communications","authors":"Lei Liang, Zhili Sun, D. He","doi":"10.1109/NGI.2005.1431693","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431693","url":null,"abstract":"All IPPM QoS parameter metrics are defined for end-to-end one-way measurement These metrics provide exact indicators of network layer quality in the pair communications. However, further attention should be put on the multiparty communications, which might use multicast routing protocols, e.g., the IP conferencing services, online gaming, online stock market and etc. To qualify the multiparty communications, the future QoS study and metrics are required to be defined. The purpose of this paper is to highlight the new QoS requirements of the multiparty communication services in terms of relative delay, relative jitter and relative packet loss. A set of parameter metrics is derived from the existing one-way metrics in IP performance metrics (IPPM) for the multiparty communications to present these new requirements. These parameter metrics are supposed to provide methods and rules for engineers to measure and judge the QoS of the multiparty communications.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133738976","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431655
Patrick Maillé
In this paper, we suggest to use an auction scheme to share the available resource of a communication link among several flows, where several users may be interested in the same flow, like multicast/streaming sessions. The auction scheme we introduce is inspired by the previously defined multi-bid auctions, which have been designed to share the available capacity of a communication link among selfish users. We study precisely the behaviour of users, and establish that their best strategy is to actually reveal what the resource is worth to them. The efficiency of the resulting allocation in terms of social welfare is also proved.
{"title":"Multicast versus private flows: an efficient pricing scheme for congestion control","authors":"Patrick Maillé","doi":"10.1109/NGI.2005.1431655","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431655","url":null,"abstract":"In this paper, we suggest to use an auction scheme to share the available resource of a communication link among several flows, where several users may be interested in the same flow, like multicast/streaming sessions. The auction scheme we introduce is inspired by the previously defined multi-bid auctions, which have been designed to share the available capacity of a communication link among selfish users. We study precisely the behaviour of users, and establish that their best strategy is to actually reveal what the resource is worth to them. The efficiency of the resulting allocation in terms of social welfare is also proved.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115050748","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431666
P. He, J. Regnier
This study investigates routing in a MPLS-based (multi-protocol label switching) IP network with heterogeneous holding time traffic (for example, an IP call versus an IP conference). Our basic idea is to exploit the large differences existing in the holding time of different types of traffic to make more efficient resource allocation decisions in the admission and routing processes. In particular, we investigate the concept of vacating, in which requests with short holding times vacate the bandwidth to requests with long holding times. Based on an analytical framework we developed, we analyze the vacating idea and propose several state-dependent routing schemes, namely preventive-vacating routing (PW), preemptive-vacating routing (PEV) and restricted-access routing (RAR). Both the analytical and simulation results indicate that within an effective range we found in traffic mix, our vacating schemes outperform the traditional LLR+TR (least loaded routing+trunk reservation) and Diff-SDR (differentiated dynamic shortest-distance routing scheme) S. Yang et al., (2001). Moreover, we deduce an approximated expression to compute the cost of accepting a long or short request, which leads to an approximated least cost routing (A-LCR) scheme. Through simulation study, A-LCR presents not only its good performing in network throughput, but also its particular flow control mechanism.
{"title":"State-dependent optimal routing in MPLS-based networks with heterogeneous flow holding times","authors":"P. He, J. Regnier","doi":"10.1109/NGI.2005.1431666","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431666","url":null,"abstract":"This study investigates routing in a MPLS-based (multi-protocol label switching) IP network with heterogeneous holding time traffic (for example, an IP call versus an IP conference). Our basic idea is to exploit the large differences existing in the holding time of different types of traffic to make more efficient resource allocation decisions in the admission and routing processes. In particular, we investigate the concept of vacating, in which requests with short holding times vacate the bandwidth to requests with long holding times. Based on an analytical framework we developed, we analyze the vacating idea and propose several state-dependent routing schemes, namely preventive-vacating routing (PW), preemptive-vacating routing (PEV) and restricted-access routing (RAR). Both the analytical and simulation results indicate that within an effective range we found in traffic mix, our vacating schemes outperform the traditional LLR+TR (least loaded routing+trunk reservation) and Diff-SDR (differentiated dynamic shortest-distance routing scheme) S. Yang et al., (2001). Moreover, we deduce an approximated expression to compute the cost of accepting a long or short request, which leads to an approximated least cost routing (A-LCR) scheme. Through simulation study, A-LCR presents not only its good performing in network throughput, but also its particular flow control mechanism.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127487282","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431665
D. Papadimitriou, Emmanuel Dotaro, M. Vigoureux
Ethernet becomes the predominant layer 2 technology in metropolitan area networks (MAN) and starts challenging multi-protocol label switching (MPLS) as the convergence layer for core networks in combination with IP. However, as these environments are driven by substantially different architectural constraints (such as meshing instead of common broadcast access segments and larger distances) the control of the Ethernet technology must be designed such that it can face these new challenges. To achieve this goal, this paper proposes to extend the capability of the generalized multi-protocol label switching (GMPLS) protocol suite to Ethernet and more generically to any layer 2 switching technology.
{"title":"Ethernet layer 2 label switched paths (LSP)","authors":"D. Papadimitriou, Emmanuel Dotaro, M. Vigoureux","doi":"10.1109/NGI.2005.1431665","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431665","url":null,"abstract":"Ethernet becomes the predominant layer 2 technology in metropolitan area networks (MAN) and starts challenging multi-protocol label switching (MPLS) as the convergence layer for core networks in combination with IP. However, as these environments are driven by substantially different architectural constraints (such as meshing instead of common broadcast access segments and larger distances) the control of the Ethernet technology must be designed such that it can face these new challenges. To achieve this goal, this paper proposes to extend the capability of the generalized multi-protocol label switching (GMPLS) protocol suite to Ethernet and more generically to any layer 2 switching technology.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131340183","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 : 2005-04-18DOI: 10.1109/NGI.2005.1431654
Werner Sandmann
Queueing theory has dealt comprehensively with waiting times, throughput, or related properties. Another important issue, which is fair queueing, has been neglected for a long time and has received reasonable attention only very recently. As of today there are no generally accepted definitions and measures although some have been proposed. It has been recognized that measuring fairness in queues suffers from the dilemma that, depending on the application, queue scheduling pursues contradictory aims. Sometimes preference is given to short jobs, sometimes to jobs that already wait for quite a long time. In both cases one may get the impression that some jobs do not receive a fair treatment. In this paper we propose a queueing fairness measure which considers both service requirement and seniority of a job or customer. Our measure counts two types of discriminations that may bother customers: to be overtaken by other customers, and to wait due to customers with large service requirements. We show that our fairness measure adheres to previously published different preference principles, and we discuss possible measure refinements and the fairness of some scheduling policies.
{"title":"A discrimination frequency based queueing fairness measure with regard to job seniority and service requirement","authors":"Werner Sandmann","doi":"10.1109/NGI.2005.1431654","DOIUrl":"https://doi.org/10.1109/NGI.2005.1431654","url":null,"abstract":"Queueing theory has dealt comprehensively with waiting times, throughput, or related properties. Another important issue, which is fair queueing, has been neglected for a long time and has received reasonable attention only very recently. As of today there are no generally accepted definitions and measures although some have been proposed. It has been recognized that measuring fairness in queues suffers from the dilemma that, depending on the application, queue scheduling pursues contradictory aims. Sometimes preference is given to short jobs, sometimes to jobs that already wait for quite a long time. In both cases one may get the impression that some jobs do not receive a fair treatment. In this paper we propose a queueing fairness measure which considers both service requirement and seniority of a job or customer. Our measure counts two types of discriminations that may bother customers: to be overtaken by other customers, and to wait due to customers with large service requirements. We show that our fairness measure adheres to previously published different preference principles, and we discuss possible measure refinements and the fairness of some scheduling policies.","PeriodicalId":435785,"journal":{"name":"Next Generation Internet Networks, 2005","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130291151","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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