Understanding the topology of large scale IPv6 networks is essential to the procurement of good architectural design decisions, particularly with respect to address allocation and distribution schemes. The former distributed topology discovery applications deploy multiple probing hosts throughout the network. This approach relies on the ability to deploy probing hosts throughout the network, which in many cases is not possible. Source routing support in IPv6 routers is a mandated feature and hence mostly enabled. With respect to simple traceroute, source routing allows one to discover paths between arbitrary pairs of network nodes, but it is such difficult to avoid probing redundancy with a null probing stopping set in the initial phrase of discovery. This paper presents two probing systems: VDPS (Virtual Distributed Probing System) and SRPS (Source Routing Probing System). Firstly, VDPS discovers the BTI (Basic Topology Information) of IPv6 networks. Secondly, SRPS selects seeds from the BTI. In the processing of SRPS, it is very effective in avoiding probing redundancy rely on the probing stopping set initiated by the BTI. Finishing the implementation of SRPS, the coverage of probing is increased greatly. We also present some initial results from probing the CERNET2, currently the largest public IPv6 network of China. The results illustrate the effectiveness of coverage and avoiding probing redundancy.
{"title":"Large Scale Topology Discovery for Public IPv6 Networks","authors":"Zhenshan Liu, Junyong Luo, Qingxian Wang","doi":"10.1109/ICN.2008.21","DOIUrl":"https://doi.org/10.1109/ICN.2008.21","url":null,"abstract":"Understanding the topology of large scale IPv6 networks is essential to the procurement of good architectural design decisions, particularly with respect to address allocation and distribution schemes. The former distributed topology discovery applications deploy multiple probing hosts throughout the network. This approach relies on the ability to deploy probing hosts throughout the network, which in many cases is not possible. Source routing support in IPv6 routers is a mandated feature and hence mostly enabled. With respect to simple traceroute, source routing allows one to discover paths between arbitrary pairs of network nodes, but it is such difficult to avoid probing redundancy with a null probing stopping set in the initial phrase of discovery. This paper presents two probing systems: VDPS (Virtual Distributed Probing System) and SRPS (Source Routing Probing System). Firstly, VDPS discovers the BTI (Basic Topology Information) of IPv6 networks. Secondly, SRPS selects seeds from the BTI. In the processing of SRPS, it is very effective in avoiding probing redundancy rely on the probing stopping set initiated by the BTI. Finishing the implementation of SRPS, the coverage of probing is increased greatly. We also present some initial results from probing the CERNET2, currently the largest public IPv6 network of China. The results illustrate the effectiveness of coverage and avoiding probing redundancy.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125188478","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}
This paper deals with the design of an algorithm and application for an automatic system of real-time audio signal quality surveillance on personal computers. This system works without any knowledge of how the audio signal is processed. The audio signal quality and possible signal failures are monitored by being compared with the original signal in the time-frequency domain. The system supports several audio formats from mono to 5.1 and downmix for comparison between different audio formats. For high performance, SIMD technologies are used. The whole system consists of several local surveillance applications (clients) and a server application with SNMP client that monitors the local application states using the TCP/IP network.
{"title":"Surveillance and Quality Evaluation System for Real-Time Audio Signal Streaming","authors":"J. Schimmel, J. Prinosil, J. Misurec","doi":"10.1109/ICN.2008.62","DOIUrl":"https://doi.org/10.1109/ICN.2008.62","url":null,"abstract":"This paper deals with the design of an algorithm and application for an automatic system of real-time audio signal quality surveillance on personal computers. This system works without any knowledge of how the audio signal is processed. The audio signal quality and possible signal failures are monitored by being compared with the original signal in the time-frequency domain. The system supports several audio formats from mono to 5.1 and downmix for comparison between different audio formats. For high performance, SIMD technologies are used. The whole system consists of several local surveillance applications (clients) and a server application with SNMP client that monitors the local application states using the TCP/IP network.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132471452","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}
The introduction of advanced radio resource management features such as directional antennas, power control and variable data rates have been proposed to increase the performance of multihop wireless networks. In this paper we will study the combined effects of adaptive rate selection and power control in spatial time division multiple access (STDMA) networks where nodes are equipped with advanced (beamforming) antennas. In our evaluation, the rates are selected from a discrete set. To assess the optimum performance of the various techniques, joint scheduling, rate and power control is done by solving a non-linear optimization problem. The results show that variable rates schemes can significantly improve the end-to-end network throughput compared to fixed rate schemes, whereas power control adds only a limited additional gain. The latter effect becomes even more pronounced as more narrow-beam antennas are used.
{"title":"On the Performance of Power and Rate Control in STDMA Multihop Networks with Advanced Antennas","authors":"Marvin Sánchez, J. Zander, Bo Hagerman","doi":"10.1109/ICN.2008.37","DOIUrl":"https://doi.org/10.1109/ICN.2008.37","url":null,"abstract":"The introduction of advanced radio resource management features such as directional antennas, power control and variable data rates have been proposed to increase the performance of multihop wireless networks. In this paper we will study the combined effects of adaptive rate selection and power control in spatial time division multiple access (STDMA) networks where nodes are equipped with advanced (beamforming) antennas. In our evaluation, the rates are selected from a discrete set. To assess the optimum performance of the various techniques, joint scheduling, rate and power control is done by solving a non-linear optimization problem. The results show that variable rates schemes can significantly improve the end-to-end network throughput compared to fixed rate schemes, whereas power control adds only a limited additional gain. The latter effect becomes even more pronounced as more narrow-beam antennas are used.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130440781","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}
In this paper we released some connection problems with BitTorrent (BT) that we have founded in our four months' experimental study. One connection per IP address is usually used by network application software for flow fairness. However if one connection per IP address is configured with BT there will be some problems in connection setup, which induces some peers not to find some of others even the number of total peers is small. These problems are caused by some bugs in the current BT. All of these problems will be detailed in this paper and modified source codes are also given. We hope this work be helpful for some researchers' experimental study, perfect BT's real use, and arouse similar project's attention to these connection problems.
{"title":"Some Connection Problems with BitTorrent","authors":"Dongliang Guan, Jiangtao Wang, Hui Chen, Junni Dong","doi":"10.1109/ICN.2008.15","DOIUrl":"https://doi.org/10.1109/ICN.2008.15","url":null,"abstract":"In this paper we released some connection problems with BitTorrent (BT) that we have founded in our four months' experimental study. One connection per IP address is usually used by network application software for flow fairness. However if one connection per IP address is configured with BT there will be some problems in connection setup, which induces some peers not to find some of others even the number of total peers is small. These problems are caused by some bugs in the current BT. All of these problems will be detailed in this paper and modified source codes are also given. We hope this work be helpful for some researchers' experimental study, perfect BT's real use, and arouse similar project's attention to these connection problems.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":"230 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132948970","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}
Privacy constitutes a great challenge for the spread of new services. In particular for Next Generation Network (NGN) services, operators and providers hold more sensitive information than traditional networks. NGN implies a new service layer, accessible by third parties through standardized interfaces. This newly proposed service architecture is not protected yet against privacy threat. We demonstrate that pseudonymity is an interesting and feasible solution in Parlay X gateway. Location-Based Services (LBS) make use of user positions, which are sensitive information, to provide more enhanced services. Different alternatives in cellular networks, exist to retrieve this information, they however don't offer the same privacy quality level. Those alternatives may cooperate to provide location information to service providers. The discontinuity of the privacy quality imperils the anonymity of users. In this paper, we propose a novel Privacy Web service added to the Parlay X gateway of the service architecture to ensure user privacy through pseudonymity in location services. The architecture is based on the enhancement of standardized Parlay X Web services. The new proposed web service could enforce the privacy provided by operator networks. A formal model of our approach is investigated.
隐私对新服务的推广构成了巨大挑战。特别是对于下一代网络(NGN)业务，运营商和提供商比传统网络拥有更多的敏感信息。NGN意味着一个新的服务层，第三方可以通过标准化接口访问。这个新提出的服务体系结构还不能防止隐私威胁。我们证明了在Parlay X网关中，匿名是一种有趣且可行的解决方案。基于位置的服务(LBS)利用用户位置这一敏感信息来提供更多的增强服务。在蜂窝网络中，存在不同的替代方案来检索这些信息，但是它们不能提供相同的隐私质量水平。这些替代方案可以合作向服务提供者提供位置信息。隐私质量的不连续性危及用户的匿名性。在本文中，我们提出了一种新的隐私Web服务，添加到服务体系结构的Parlay X网关中，通过在位置服务中使用假名来确保用户的隐私。该体系结构基于对标准化Parlay X Web服务的增强。新提议的网络服务可以加强运营商网络提供的隐私保护。研究了该方法的形式化模型。
{"title":"Privacy Improvement through Pseudonymity in Parlay X for Location Based Services","authors":"N. Ajam, A. Bouabdallah","doi":"10.1109/ICN.2008.108","DOIUrl":"https://doi.org/10.1109/ICN.2008.108","url":null,"abstract":"Privacy constitutes a great challenge for the spread of new services. In particular for Next Generation Network (NGN) services, operators and providers hold more sensitive information than traditional networks. NGN implies a new service layer, accessible by third parties through standardized interfaces. This newly proposed service architecture is not protected yet against privacy threat. We demonstrate that pseudonymity is an interesting and feasible solution in Parlay X gateway. Location-Based Services (LBS) make use of user positions, which are sensitive information, to provide more enhanced services. Different alternatives in cellular networks, exist to retrieve this information, they however don't offer the same privacy quality level. Those alternatives may cooperate to provide location information to service providers. The discontinuity of the privacy quality imperils the anonymity of users. In this paper, we propose a novel Privacy Web service added to the Parlay X gateway of the service architecture to ensure user privacy through pseudonymity in location services. The architecture is based on the enhancement of standardized Parlay X Web services. The new proposed web service could enforce the privacy provided by operator networks. A formal model of our approach is investigated.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133108688","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}
In recent time we spot a tendency to use the computing capacity of workstation clusters instead of investing in single machines with tremendous calculation power. Applying this idea we are able to execute multiple jobs paralelly. However, it still remains unclear how to schedule given jobs among available machines most effectively. Therefore this paper is an approach to optimization of mentioned scheduling. The problem faced here is known in the literature as parallel machine earliness-tardiness scheduling (PMSP_E/T). The optimum criterion is finding the minimal sum of the weighted earliness and tardiness penalties. Due to NP-hardness of specified problem and thus difficulty in locating the optimum we propose two heuristic algorithms to find a satisfying solution: genetic with MCUOX crossover operator and tabu search. We have conducted a research to compare the effectiveness of both approaches and display their dependence on the size of examined instances. Results proove genetic approach superiority over tabu search for larger instances.
{"title":"Scheduling on Networks of Workstations with Task Runtime Restrictions","authors":"M. Bazyluk, L. Koszalka, K. Burnham","doi":"10.1109/ICN.2008.82","DOIUrl":"https://doi.org/10.1109/ICN.2008.82","url":null,"abstract":"In recent time we spot a tendency to use the computing capacity of workstation clusters instead of investing in single machines with tremendous calculation power. Applying this idea we are able to execute multiple jobs paralelly. However, it still remains unclear how to schedule given jobs among available machines most effectively. Therefore this paper is an approach to optimization of mentioned scheduling. The problem faced here is known in the literature as parallel machine earliness-tardiness scheduling (PMSP_E/T). The optimum criterion is finding the minimal sum of the weighted earliness and tardiness penalties. Due to NP-hardness of specified problem and thus difficulty in locating the optimum we propose two heuristic algorithms to find a satisfying solution: genetic with MCUOX crossover operator and tabu search. We have conducted a research to compare the effectiveness of both approaches and display their dependence on the size of examined instances. Results proove genetic approach superiority over tabu search for larger instances.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":" 24","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133120586","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}
The need for supporting real time and multimedia applications for users of mobile ad hoc network (MANET) is becoming essential. Mobile ad hoc networks can provide multimedia users with mobility they demand, if efficient QoS multicast strategies were developed. The aim of this article is to define the building blocks of such an ad hoc QoS multicasting (AQM) protocol and propose a cross layer framework to support QoS multicasting. AQM achieves multicasting efficiency by tracking the availability of resources for each node within its neighbourhood. Computation of free bandwidth is based on reservations made for ongoing sessions and similar information reported by neighbours. Current QoS status is announced at the initiation of a new session and updated periodically in the network to the extent of QoS provision. Thus, nodes are prevented from applying for membership if there is no QoS path for the session. When nodes join a session with certain service requirements, a request-reply- reserve process ensures that the QoS information is refreshed and used to select the most appropriate routes. To evaluate the efficiency of AQM in providing multicast users with QoS and satisfying application requirements, two new performance metrics, member and session satisfaction grades are introduced. AQM is compared to a non- QoS scheme with particular emphasis on these criteria. Simulation results show that, by applying QoS restrictions, AQM significantly improves multicasting efficiency. Thus, QoS is both essential for and applicable to multicasting in order to support mobile multimedia applications in ad hoc networks.
{"title":"QOS Multicast Routing Based on Bandwidth and Resource Availability in Mobile Adhoc Networks","authors":"G. Narsimha, A. V. Reddy, B. Kumar","doi":"10.1109/ICN.2008.118","DOIUrl":"https://doi.org/10.1109/ICN.2008.118","url":null,"abstract":"The need for supporting real time and multimedia applications for users of mobile ad hoc network (MANET) is becoming essential. Mobile ad hoc networks can provide multimedia users with mobility they demand, if efficient QoS multicast strategies were developed. The aim of this article is to define the building blocks of such an ad hoc QoS multicasting (AQM) protocol and propose a cross layer framework to support QoS multicasting. AQM achieves multicasting efficiency by tracking the availability of resources for each node within its neighbourhood. Computation of free bandwidth is based on reservations made for ongoing sessions and similar information reported by neighbours. Current QoS status is announced at the initiation of a new session and updated periodically in the network to the extent of QoS provision. Thus, nodes are prevented from applying for membership if there is no QoS path for the session. When nodes join a session with certain service requirements, a request-reply- reserve process ensures that the QoS information is refreshed and used to select the most appropriate routes. To evaluate the efficiency of AQM in providing multicast users with QoS and satisfying application requirements, two new performance metrics, member and session satisfaction grades are introduced. AQM is compared to a non- QoS scheme with particular emphasis on these criteria. Simulation results show that, by applying QoS restrictions, AQM significantly improves multicasting efficiency. Thus, QoS is both essential for and applicable to multicasting in order to support mobile multimedia applications in ad hoc networks.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133152177","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}
The diversity of the applications supported by wireless ad hoc and sensor networks explain the success of these networks. However, their energy constrained nature requires the use of energy efficient strategies to maximize network lifetime. We can classify these strategies in four categories: 1. energy efficient routing, 2. scheduling the nodes sleeping state, 3. topology control by tuning node transmission power and 4. reducing the volume of information transferred. For each category, a state of the art is given and new protocols are presented. The best energy efficiency will be obtained by combining all the four categories of strategies. A cross-layering approach is a promising tradeoff between generic solutions and solutions optimized for a specific application.
{"title":"Survey of Energy Efficient Strategies in Wireless Ad Hoc and Sensor Networks","authors":"S. Mahfoudh, P. Minet","doi":"10.1109/ICN.2008.55","DOIUrl":"https://doi.org/10.1109/ICN.2008.55","url":null,"abstract":"The diversity of the applications supported by wireless ad hoc and sensor networks explain the success of these networks. However, their energy constrained nature requires the use of energy efficient strategies to maximize network lifetime. We can classify these strategies in four categories: 1. energy efficient routing, 2. scheduling the nodes sleeping state, 3. topology control by tuning node transmission power and 4. reducing the volume of information transferred. For each category, a state of the art is given and new protocols are presented. The best energy efficiency will be obtained by combining all the four categories of strategies. A cross-layering approach is a promising tradeoff between generic solutions and solutions optimized for a specific application.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123523843","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}
LSP path selection problem in MPLS network has been a hot research field. For unicast, there are already many algorithms to solve it, making the network more resource balanced and useable. Among these algorithms, Minimal Interference Routing Algorithm (MIRA) is the most valued one. This paper presents a novel algorithm for multicast LSP setting up problem based on MIRA, which replaces Maxflow with K time Dijkstra algorithm, and the experiment result shows it achieves much less complexity than traditional algorithm MIRA while providing a good conflict avoiding mechanism.
{"title":"L-MMIRA: Light Multicast Minimal Interference Routing Module in MPLS Network","authors":"Li Xuan, Li Ying","doi":"10.1109/ICN.2008.34","DOIUrl":"https://doi.org/10.1109/ICN.2008.34","url":null,"abstract":"LSP path selection problem in MPLS network has been a hot research field. For unicast, there are already many algorithms to solve it, making the network more resource balanced and useable. Among these algorithms, Minimal Interference Routing Algorithm (MIRA) is the most valued one. This paper presents a novel algorithm for multicast LSP setting up problem based on MIRA, which replaces Maxflow with K time Dijkstra algorithm, and the experiment result shows it achieves much less complexity than traditional algorithm MIRA while providing a good conflict avoiding mechanism.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116395816","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}
In this paper, we present some principles of grid economy, why it's useful to scheduling task and what is involved in a Grid computing. And we present some results obtained with a framework that use the two model of economy to form a price of a service based, in a macroeconomic way is attributed a initial price for a resource based in your computation characteristics, this is a commodities market, and the microeconomic way, with the node varying your local price based on the demand/supply economic model.
{"title":"A Price-Based Task Scheduling for Grid Computing","authors":"Marcelo Massocco Cendron, Carlos Becker Westphall","doi":"10.1109/ICN.2008.125","DOIUrl":"https://doi.org/10.1109/ICN.2008.125","url":null,"abstract":"In this paper, we present some principles of grid economy, why it's useful to scheduling task and what is involved in a Grid computing. And we present some results obtained with a framework that use the two model of economy to form a price of a service based, in a macroeconomic way is attributed a initial price for a resource based in your computation characteristics, this is a commodities market, and the microeconomic way, with the node varying your local price based on the demand/supply economic model.","PeriodicalId":250085,"journal":{"name":"Seventh International Conference on Networking (icn 2008)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117238674","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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