Pub Date : 1993-03-28DOI: 10.1109/INFCOM.1993.253339
V. F. Hartanto, H. Sirisena
In currently proposed asynchronous transfer mode (ATM) congestion control schemes, the policing function is carried out at the network edge, which opens the possibility of cells being discarded or marked without reference to the actual message. This can lead to degradation of the service quality in the voice service or multiplication of the cell loss probability in the data service. The authors propose an approach to the policing function, called user-network policer, to resolve these problems. The scheme consists of a service-dependent user policer and a service-independent network policer. Users are responsible for policing and marking their traffic appropriately before sending them into the network. The network is only responsible for verifying the correctness of user policing and for transporting cells transparently across the network.<>
{"title":"User-network policer: a new approach for ATM congestion control","authors":"V. F. Hartanto, H. Sirisena","doi":"10.1109/INFCOM.1993.253339","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253339","url":null,"abstract":"In currently proposed asynchronous transfer mode (ATM) congestion control schemes, the policing function is carried out at the network edge, which opens the possibility of cells being discarded or marked without reference to the actual message. This can lead to degradation of the service quality in the voice service or multiplication of the cell loss probability in the data service. The authors propose an approach to the policing function, called user-network policer, to resolve these problems. The scheme consists of a service-dependent user policer and a service-independent network policer. Users are responsible for policing and marking their traffic appropriately before sending them into the network. The network is only responsible for verifying the correctness of user policing and for transporting cells transparently across the network.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"309 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114656269","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 : 1993-03-28DOI: 10.1109/INFCOM.1993.253275
D. Reininger, D. Raychaudhuri, B. Melamed, B. Sengupta, Jon R. Hill
A variable-bit-rate (VBR) MPEG video compression encoder is introduced, and the performance of a statistically multiplexed asynchronous transfer mode (ATM) network supporting a number of such VBR video sources is evaluated. Bit-rate characteristics obtained from a detailed simulation are provided for a VBR MPEG encoder for CCIR601 video (operating in the 5-10 Mb/s regime) appropriate for medium-quality multimedia or broadcasting applications. The results presented include bit-rate traces and signal-to-noise-ratio data for typical test sequences, along with summary statistics such as the marginal distribution of frame rate. Data from a study of statistical multiplexing on an ATM network are also given. Simulation results for an ATM statistical multiplexer with N>>1 VBR MPEG sources are presented in terms of key performance measures such as cell loss rate and delay versus throughput. The results confirm that ATM channel efficiencies of approximately 80-90% can be obtained at reasonable cell loss rate and delay levels.<>
{"title":"Statistical multiplexing of VBR MPEG compressed video on ATM networks","authors":"D. Reininger, D. Raychaudhuri, B. Melamed, B. Sengupta, Jon R. Hill","doi":"10.1109/INFCOM.1993.253275","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253275","url":null,"abstract":"A variable-bit-rate (VBR) MPEG video compression encoder is introduced, and the performance of a statistically multiplexed asynchronous transfer mode (ATM) network supporting a number of such VBR video sources is evaluated. Bit-rate characteristics obtained from a detailed simulation are provided for a VBR MPEG encoder for CCIR601 video (operating in the 5-10 Mb/s regime) appropriate for medium-quality multimedia or broadcasting applications. The results presented include bit-rate traces and signal-to-noise-ratio data for typical test sequences, along with summary statistics such as the marginal distribution of frame rate. Data from a study of statistical multiplexing on an ATM network are also given. Simulation results for an ATM statistical multiplexer with N>>1 VBR MPEG sources are presented in terms of key performance measures such as cell loss rate and delay versus throughput. The results confirm that ATM channel efficiencies of approximately 80-90% can be obtained at reasonable cell loss rate and delay levels.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130334119","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 : 1993-03-28DOI: 10.1109/INFCOM.1993.253346
Yao-Min Chen, G. Sasaki
The irregular torus, a class of topologies proposed for metropolitan area networks, is torus-like, and thus more reliable than the bus and ring topologies. There is a routing algorithm for the topologies which is space and time efficient so that it is suitable for high-speed implementations. In addition, it is robust to topology perturbations due to network growth and node/link failure. A buffer management is proposed to prevent store-and-forward deadlock for routing in the irregular torus, and the throughput of a typical irregular torus network is analyzed. Store-and-forward deadlock is avoided by a buffer management whose storage requirement and control complexity at a node are both constant with the size of a network. The throughput of a typical irregular torus network is shown to be within a constant factor of that of a square torus. Hence for a large number of nodes, it is much higher than the throughput of a bus, ring or tree.<>
{"title":"Irregular torus networks: deadlock avoidance and throughput analysis","authors":"Yao-Min Chen, G. Sasaki","doi":"10.1109/INFCOM.1993.253346","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253346","url":null,"abstract":"The irregular torus, a class of topologies proposed for metropolitan area networks, is torus-like, and thus more reliable than the bus and ring topologies. There is a routing algorithm for the topologies which is space and time efficient so that it is suitable for high-speed implementations. In addition, it is robust to topology perturbations due to network growth and node/link failure. A buffer management is proposed to prevent store-and-forward deadlock for routing in the irregular torus, and the throughput of a typical irregular torus network is analyzed. Store-and-forward deadlock is avoided by a buffer management whose storage requirement and control complexity at a node are both constant with the size of a network. The throughput of a typical irregular torus network is shown to be within a constant factor of that of a square torus. Hence for a large number of nodes, it is much higher than the throughput of a bus, ring or tree.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130347419","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 : 1993-03-28DOI: 10.1109/INFCOM.1993.253391
R. Bolla, F. Danovaro, F. Davoli, M. Marchese
Dynamic bandwidth allocation among traffic classes with different performance requirements sharing an asynchronous transfer mode (ATM) link is considered as an integrated control problem with a multilevel structure. At the lower level, call admission control rules are applied that maintain a certain grade of service, in terms of cell loss probability and cell delay, given the buffer space and bandwidth assigned to each class; unlike those used in previous works, these rules are derived on the basis of homogeneous (based on similar quantities) measures of the performance requirements. At the higher level, bandwidth shares are periodically recomputed online by an allocation controller, whose goals reflect overall cell loss and refused traffic, as well as overall average delay. These goals are expressed by an optimization problem that is solved by numerical techniques. The whole control system should provide a dynamic feedback controller, capable of reacting in real time to changes in the traffic patterns. Simulation results are presented and are discussed in regard to the efficiency of the admission controllers, the performance of the overall scheme, and the capability of reacting to sudden changes in the load of some traffic class.<>
{"title":"An integrated dynamic resource allocation scheme for ATM networks","authors":"R. Bolla, F. Danovaro, F. Davoli, M. Marchese","doi":"10.1109/INFCOM.1993.253391","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253391","url":null,"abstract":"Dynamic bandwidth allocation among traffic classes with different performance requirements sharing an asynchronous transfer mode (ATM) link is considered as an integrated control problem with a multilevel structure. At the lower level, call admission control rules are applied that maintain a certain grade of service, in terms of cell loss probability and cell delay, given the buffer space and bandwidth assigned to each class; unlike those used in previous works, these rules are derived on the basis of homogeneous (based on similar quantities) measures of the performance requirements. At the higher level, bandwidth shares are periodically recomputed online by an allocation controller, whose goals reflect overall cell loss and refused traffic, as well as overall average delay. These goals are expressed by an optimization problem that is solved by numerical techniques. The whole control system should provide a dynamic feedback controller, capable of reacting in real time to changes in the traffic patterns. Simulation results are presented and are discussed in regard to the efficiency of the admission controllers, the performance of the overall scheme, and the capability of reacting to sudden changes in the load of some traffic class.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"3 9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127465745","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 : 1993-03-28DOI: 10.1109/INFCOM.1993.253333
R. LaMaire, A. Krishna, H. Ahmadi
An efficient medium access control (MAC) protocol for use in a single cell of a wireless local area network (LAN) is analyzed. A fixed frame structure with two periods is used, one period for making reservations using a slotted Aloha protocol and a second period for data transmission. The MAC protocol operates in a centralized manner in which a single station, the base station, accepts reservations (transmission or data requests) that are made by the remote stations, and then schedules the times in which they will transmit or receive data. Two different types of client-server traffic models, open loop and closed loop, are considered. Exact results are derived for the mean throughput and waiting times as well as for the queue length distributions. Several types of behavior are illustrated by numerical examples.<>
{"title":"Analysis of a wireless MAC protocol with client-server traffic","authors":"R. LaMaire, A. Krishna, H. Ahmadi","doi":"10.1109/INFCOM.1993.253333","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253333","url":null,"abstract":"An efficient medium access control (MAC) protocol for use in a single cell of a wireless local area network (LAN) is analyzed. A fixed frame structure with two periods is used, one period for making reservations using a slotted Aloha protocol and a second period for data transmission. The MAC protocol operates in a centralized manner in which a single station, the base station, accepts reservations (transmission or data requests) that are made by the remote stations, and then schedules the times in which they will transmit or receive data. Two different types of client-server traffic models, open loop and closed loop, are considered. Exact results are derived for the mean throughput and waiting times as well as for the queue length distributions. Several types of behavior are illustrated by numerical examples.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128846119","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 : 1993-03-28DOI: 10.1109/INFCOM.1993.253340
I. Rubin, Ho-Ting Wu
The authors propose and study a protocol for asynchronous transfer mode (ATM) networks, called the fair and efficient cyclic control algorithm (FECCA), which combines the advantages of both global and local fairness schemes, to achieve a fair access mechanism while yielding high network throughput levels for a full-duplex ring network with spatial reuse. In addition, through the use of queuing models and analytical approximations, they present an analytical method for evaluating the network throughput performance for a special network topology. The analytical performance results are shown to be close to those obtained by simulations.<>
{"title":"FECCA-a new access algorithm for an ATM ring network with destination removal","authors":"I. Rubin, Ho-Ting Wu","doi":"10.1109/INFCOM.1993.253340","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253340","url":null,"abstract":"The authors propose and study a protocol for asynchronous transfer mode (ATM) networks, called the fair and efficient cyclic control algorithm (FECCA), which combines the advantages of both global and local fairness schemes, to achieve a fair access mechanism while yielding high network throughput levels for a full-duplex ring network with spatial reuse. In addition, through the use of queuing models and analytical approximations, they present an analytical method for evaluating the network throughput performance for a special network topology. The analytical performance results are shown to be close to those obtained by simulations.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130437517","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 : 1993-03-28DOI: 10.1109/INFCOM.1993.253309
C. Papadopoulos, G. Parulkar
Results of a study that attempts to characterize the performance of the SunOS Inter-Process Communication (IPC) and TCP/IP protocols for distributed high-bandwidth applications are presented. In general, it is found that the performance of SunOS 4.0.3 IPC on Sparcstation 1 over the Ethernet is very good. An experiment has shown that average throughput rates of up to 7.5 Mb/s are achievable. Further investigation has shown that this rate is not limited by the TCP/IP performance, but by the driver performance. Therefore, a better driver implementation will increase throughput further. Some improvements to the default IPC are still possible. The performance of IPC for local processes is estimated to be about 43% of the memory bandwidth. The interaction of computation and communication is significant. An experiment has shown that the additional load on the machine greatly decreases throughput.<>
{"title":"Experimental evaluation of SunOS IPC and TCP/IP protocol implementation","authors":"C. Papadopoulos, G. Parulkar","doi":"10.1109/INFCOM.1993.253309","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253309","url":null,"abstract":"Results of a study that attempts to characterize the performance of the SunOS Inter-Process Communication (IPC) and TCP/IP protocols for distributed high-bandwidth applications are presented. In general, it is found that the performance of SunOS 4.0.3 IPC on Sparcstation 1 over the Ethernet is very good. An experiment has shown that average throughput rates of up to 7.5 Mb/s are achievable. Further investigation has shown that this rate is not limited by the TCP/IP performance, but by the driver performance. Therefore, a better driver implementation will increase throughput further. Some improvements to the default IPC are still possible. The performance of IPC for local processes is estimated to be about 43% of the memory bandwidth. The interaction of computation and communication is significant. An experiment has shown that the additional load on the machine greatly decreases throughput.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117245746","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 : 1993-03-28DOI: 10.1109/INFCOM.1993.253266
K. Luo, W. Klostermeyer, Y. Chow
The store-and-forward deadlock problem in packet switching networks is considered. Most of the previous work addressed this issue using reserved buffers, and most algorithms, with the exception of that given by J. Blazewicz et al. (1987) (the BBG algorithm), use more reserved buffers than necessary, implying that each node does not have the maximum flexibility in message routing. It is shown that the BBG deadlock prevention algorithm can generate an unbounded number of backtracked messages. A deadlock detection and resolution algorithm that allows a minimum number of buffers to be reserved and minimizes the number of backtracked messages at the end of each detection and resolution is presented. It is shown that in the worst case, only O( mod E mod ) backtracked messages can be generated as a result of this algorithm, and that each backtracked message is backtracked only one hop.<>
研究了分组交换网络中的存储转发死锁问题。之前的大部分工作都使用保留缓冲区来解决这个问题，而且除了J. Blazewicz等人(1987)给出的算法(BBG算法)之外，大多数算法都使用了比必要更多的保留缓冲区，这意味着每个节点在消息路由中没有最大的灵活性。研究表明，BBG死锁预防算法可以产生无限数量的回溯消息。提出了一种死锁检测和解决算法，该算法允许保留最小数量的缓冲区，并在每次检测和解决结束时最小化回溯消息的数量。结果表明，在最坏的情况下，该算法只能生成O(mod E mod)个回调消息，并且每个回调消息只回调一跳。
{"title":"A distributed algorithm for detecting and resolving store-and-forward deadlocks in networks with minimum exchange buffers","authors":"K. Luo, W. Klostermeyer, Y. Chow","doi":"10.1109/INFCOM.1993.253266","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253266","url":null,"abstract":"The store-and-forward deadlock problem in packet switching networks is considered. Most of the previous work addressed this issue using reserved buffers, and most algorithms, with the exception of that given by J. Blazewicz et al. (1987) (the BBG algorithm), use more reserved buffers than necessary, implying that each node does not have the maximum flexibility in message routing. It is shown that the BBG deadlock prevention algorithm can generate an unbounded number of backtracked messages. A deadlock detection and resolution algorithm that allows a minimum number of buffers to be reserved and minimizes the number of backtracked messages at the end of each detection and resolution is presented. It is shown that in the worst case, only O( mod E mod ) backtracked messages can be generated as a result of this algorithm, and that each backtracked message is backtracked only one hop.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"690 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122979978","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 : 1993-03-28DOI: 10.1109/INFCOM.1993.253331
E. Modiano, A. Ephremides
An approximate model for analyzing interacting queues is developed. This approximation models an N-dimensional infinite Markov chain by means of two Markov chains, one being one-dimensional and infinite and the other being N-dimensional and finite. The transition probabilities of each chain are expressed in terms of statistics of the other chain. The two chains are solved together iteratively to yield an approximation to the original N-dimensional infinite chain. The model is used to analyze systems of dependent queues which often arise in multiple access protocols. It is shown how this model can be used to analyze the ALOHA multiple access protocol as well as a previously proposed broadcast algorithm for a mesh network. The results compare very well with simulation.<>
{"title":"A method for delay analysis of interacting queues in multiple access systems","authors":"E. Modiano, A. Ephremides","doi":"10.1109/INFCOM.1993.253331","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253331","url":null,"abstract":"An approximate model for analyzing interacting queues is developed. This approximation models an N-dimensional infinite Markov chain by means of two Markov chains, one being one-dimensional and infinite and the other being N-dimensional and finite. The transition probabilities of each chain are expressed in terms of statistics of the other chain. The two chains are solved together iteratively to yield an approximation to the original N-dimensional infinite chain. The model is used to analyze systems of dependent queues which often arise in multiple access protocols. It is shown how this model can be used to analyze the ALOHA multiple access protocol as well as a previously proposed broadcast algorithm for a mesh network. The results compare very well with simulation.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115184226","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 : 1993-03-28DOI: 10.1109/INFCOM.1993.253232
D. Logothetis, Kishor S. Trivedi
Five different attachment schemes proposed for the FDDI (fiber distributed data interface) token ring are compared in terms of reliability. For this purpose, the topologies are first studied in isolation (reliability of the path to the backbone) and subsequently end-to-end user reliabilities are computed by combining backbone reliability with the reliability of the path to the backbone.<>
{"title":"Reliability analysis of various station attachment schemes in a FDDI token ring","authors":"D. Logothetis, Kishor S. Trivedi","doi":"10.1109/INFCOM.1993.253232","DOIUrl":"https://doi.org/10.1109/INFCOM.1993.253232","url":null,"abstract":"Five different attachment schemes proposed for the FDDI (fiber distributed data interface) token ring are compared in terms of reliability. For this purpose, the topologies are first studied in isolation (reliability of the path to the backbone) and subsequently end-to-end user reliabilities are computed by combining backbone reliability with the reliability of the path to the backbone.<<ETX>>","PeriodicalId":166966,"journal":{"name":"IEEE INFOCOM '93 The Conference on Computer Communications, Proceedings","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115741267","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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