Pub Date : 1998-06-22DOI: 10.1109/ICATM.1998.688195
B. Kim, C. Thompson
In this work we examine the problem of regulating available bit rate (ABR) traffic in an ATM network. The issue of providing control signals to throttled sources at distant locations from a bottlenecked node is of particular interest. The process of modeling and design of the controller is outlined. A linear quadratic tracker is used to provide the appropriate control signal to each source. It is shown that designing the controller for minimum error energy resulted in the best tracking performance. However this result is obtained at the expense of VC buffer time delays. This situation is remedied by the addition of a simple regulator. Using a regulator one can obtain low buffer overshoot in the transient period while maintaining the good link utilization in the steady-state period.
{"title":"ABR traffic control in ATM networks using optimal control theory","authors":"B. Kim, C. Thompson","doi":"10.1109/ICATM.1998.688195","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688195","url":null,"abstract":"In this work we examine the problem of regulating available bit rate (ABR) traffic in an ATM network. The issue of providing control signals to throttled sources at distant locations from a bottlenecked node is of particular interest. The process of modeling and design of the controller is outlined. A linear quadratic tracker is used to provide the appropriate control signal to each source. It is shown that designing the controller for minimum error energy resulted in the best tracking performance. However this result is obtained at the expense of VC buffer time delays. This situation is remedied by the addition of a simple regulator. Using a regulator one can obtain low buffer overshoot in the transient period while maintaining the good link utilization in the steady-state period.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126331988","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 : 1998-06-22DOI: 10.1109/ICATM.1998.688171
Wei-Kuo Liao, L. Ni
Dynamic multicast allows members to join or leave the multicast session during its active period. In this paper, we propose a dynamic multicast routing scheme which integrates the consideration of maximum-free-circuit routing on loss networks and changes of membership. Two reference reward estimation schemes, the uniform reference reward scheme and weighted reference reward scheme for the maximum-free-circuit routing are proposed. Routing algorithms consisting of the initial connection setup as well as the joining and leaving of members are also developed. Using simulation experiments, the benefits of the weighted reference reward involve more revenue generated and a higher probability for successfully connecting a member when it issues a join request. On the other hand, the routing algorithm based on the uniform reference reward scheme can connect more members in the initial connection setup.
{"title":"Dynamic multicast on loss networks","authors":"Wei-Kuo Liao, L. Ni","doi":"10.1109/ICATM.1998.688171","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688171","url":null,"abstract":"Dynamic multicast allows members to join or leave the multicast session during its active period. In this paper, we propose a dynamic multicast routing scheme which integrates the consideration of maximum-free-circuit routing on loss networks and changes of membership. Two reference reward estimation schemes, the uniform reference reward scheme and weighted reference reward scheme for the maximum-free-circuit routing are proposed. Routing algorithms consisting of the initial connection setup as well as the joining and leaving of members are also developed. Using simulation experiments, the benefits of the weighted reference reward involve more revenue generated and a higher probability for successfully connecting a member when it issues a join request. On the other hand, the routing algorithm based on the uniform reference reward scheme can connect more members in the initial connection setup.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134456072","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 : 1998-06-22DOI: 10.1109/ICATM.1998.688172
S. Takagi, Y. Tanaka, H. Tominaga
Multicast services will occupy a large portion of the B-ISDN traffic. However, even if one multicast service is watched by many subscribers, it occupies only one channel on the trunkline as multicast traffic is not dominant on the trunkline. Therefore, it is a waste to use non-blocking multicast ATM switching networks for transit switching systems because the hardware of a non-blocking multicast ATM switching network is large. This paper proposes to apply the Batcher banyan network, which is point-to-point non-blocking, to multicast transit switching systems. The blocking rate decreases substantially by placing cell copy preparation stages in front of the Batcher network.
{"title":"Batcher banyan network with cell copy preparation stages for multicast switching","authors":"S. Takagi, Y. Tanaka, H. Tominaga","doi":"10.1109/ICATM.1998.688172","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688172","url":null,"abstract":"Multicast services will occupy a large portion of the B-ISDN traffic. However, even if one multicast service is watched by many subscribers, it occupies only one channel on the trunkline as multicast traffic is not dominant on the trunkline. Therefore, it is a waste to use non-blocking multicast ATM switching networks for transit switching systems because the hardware of a non-blocking multicast ATM switching network is large. This paper proposes to apply the Batcher banyan network, which is point-to-point non-blocking, to multicast transit switching systems. The blocking rate decreases substantially by placing cell copy preparation stages in front of the Batcher network.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133311331","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 : 1998-06-22DOI: 10.1109/ICATM.1998.688219
D. Lloyd
The process of routing, that is, the handling of Internet protocol (IP) packets at layer 3 (the network layer), is a potential bottleneck in large intranets and the public Internet. Asynchronous transfer mode (ATM) provides a hardware capability of switching cells at very high speeds at layer 2 (the link layer). A number of schemes for supporting IP over ATM hardware have emerged in recent years. These techniques may be broadly categorised by the approach they employ to set up paths through the network, namely, traffic-driven and control-driven. We propose a hybrid scheme, which while being essentially traffic-driven, exhibits advantages of both the traffic-driven and control-driven approaches.
{"title":"Smart IP switching: a hybrid system for fast IP-based network backbones","authors":"D. Lloyd","doi":"10.1109/ICATM.1998.688219","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688219","url":null,"abstract":"The process of routing, that is, the handling of Internet protocol (IP) packets at layer 3 (the network layer), is a potential bottleneck in large intranets and the public Internet. Asynchronous transfer mode (ATM) provides a hardware capability of switching cells at very high speeds at layer 2 (the link layer). A number of schemes for supporting IP over ATM hardware have emerged in recent years. These techniques may be broadly categorised by the approach they employ to set up paths through the network, namely, traffic-driven and control-driven. We propose a hybrid scheme, which while being essentially traffic-driven, exhibits advantages of both the traffic-driven and control-driven approaches.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114386667","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 : 1998-06-22DOI: 10.1109/ICATM.1998.688176
B. Maaref, S. Nasri, P. Sicard, Saint Martin D’Hkres
The broadband integrated service digital network (B-ISDN) will have to offer real-time communication services; that is, it will have to transport information with performance guarantees. In this paper, we propose a communication system for real-time applications using a 155 Mbits/sec ATM (asynchronous transfer mode) switch. This system is based on an intelligent communication board for PCs (personal computer). It integrates a transputer, an FPGA (field programmable gate array), and a VRAM (video random access memory) to implement flexible high level communication services. These services are adapted for real-time data transmission on a local area network based on the ATM standard. The main advantages of our architecture are the path redundancy, the large spectrum of traffic, and the high bandwidth inside the workstation. We discuss the implementation structure of our ATM communication board and evaluate its performance.
{"title":"An architecture for flexible high level communication services","authors":"B. Maaref, S. Nasri, P. Sicard, Saint Martin D’Hkres","doi":"10.1109/ICATM.1998.688176","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688176","url":null,"abstract":"The broadband integrated service digital network (B-ISDN) will have to offer real-time communication services; that is, it will have to transport information with performance guarantees. In this paper, we propose a communication system for real-time applications using a 155 Mbits/sec ATM (asynchronous transfer mode) switch. This system is based on an intelligent communication board for PCs (personal computer). It integrates a transputer, an FPGA (field programmable gate array), and a VRAM (video random access memory) to implement flexible high level communication services. These services are adapted for real-time data transmission on a local area network based on the ATM standard. The main advantages of our architecture are the path redundancy, the large spectrum of traffic, and the high bandwidth inside the workstation. We discuss the implementation structure of our ATM communication board and evaluate its performance.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133300641","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 : 1998-06-22DOI: 10.1109/ICATM.1998.688221
K. Wipusitwarakun, H. Tode, H. Ikeda
This paper discusses the self-healing performance of the new network environment: "variable bandwidth virtual path ATM network", which is suitable for realizing cost-effective B-ISDN and providing various low-cost multimedia services. This network environment is based on the VP-based ATM network architecture and employs bandwidth-resizing technologies for adjusting the bandwidth of VP connections corresponding to changes of their traversing traffic. In this paper, self-healing algorithms are categorized into the pre-plan algorithm and real-time algorithm, whose performances are affected by the variation of the VP's bandwidth in the network. We have developed a simple evaluation model of the variable bandwidth VP network environment for evaluating the pre-plan and real-time algorithms. These 2 algorithms are evaluated based on: (a) the required spare capacities, (b) the restoration time and (c) the robustness to unexpected wide area failure. The simulation results suggests that the real-time restoration algorithm is more suitable for the variable bandwidth VP network environment than the pre-plan restoration algorithm. This is due to it requiring less spare capacity and having greater robustness against wide area failures or topological changes. In addition, the priority-based restoration function is also essential to the self-healing algorithm since it can keep the restoration ratio of the high priority failed VP's at a high value even in a severe situation such as wide-area unexpected failures.
{"title":"The variable bandwidth virtual path ATM network and its self-healing performance","authors":"K. Wipusitwarakun, H. Tode, H. Ikeda","doi":"10.1109/ICATM.1998.688221","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688221","url":null,"abstract":"This paper discusses the self-healing performance of the new network environment: \"variable bandwidth virtual path ATM network\", which is suitable for realizing cost-effective B-ISDN and providing various low-cost multimedia services. This network environment is based on the VP-based ATM network architecture and employs bandwidth-resizing technologies for adjusting the bandwidth of VP connections corresponding to changes of their traversing traffic. In this paper, self-healing algorithms are categorized into the pre-plan algorithm and real-time algorithm, whose performances are affected by the variation of the VP's bandwidth in the network. We have developed a simple evaluation model of the variable bandwidth VP network environment for evaluating the pre-plan and real-time algorithms. These 2 algorithms are evaluated based on: (a) the required spare capacities, (b) the restoration time and (c) the robustness to unexpected wide area failure. The simulation results suggests that the real-time restoration algorithm is more suitable for the variable bandwidth VP network environment than the pre-plan restoration algorithm. This is due to it requiring less spare capacity and having greater robustness against wide area failures or topological changes. In addition, the priority-based restoration function is also essential to the self-healing algorithm since it can keep the restoration ratio of the high priority failed VP's at a high value even in a severe situation such as wide-area unexpected failures.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116231525","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 : 1998-06-22DOI: 10.1109/ICATM.1998.688163
D. Patiyoot, S. Shepherd
With the growing acceptance of ATM as the standard for broadband networking and the increasing importance of wireless devices, it has become appropriate to extend ATM application to wireless platforms. Adding a wireless network to existing wired networks creates a new set of problems. Security functions have to be reconsidered since wired network security does not account for the open medium, mobile roaming. A necessary foundation for securing a network is the ability to authenticate entities. There is a need to authenticate users of the system so that the resources will not be misused by nonsubscribers. After authentication by a suitable protocol, two parties involved in communications should be entitled to believe that they are communicating with each other and not with intruders. Good authentication is that which allows entities to provide evidence that they know a particular secret without revealing the secret. It should not provide any information to impersonators or eavesdroppers while being authenticated. In mobile networks, normally secret-key cryptography is used for authentication. In this paper, both secret-key and public-key cryptography are used in wireless ATM networks.
{"title":"Authentication protocols for wireless ATM networks","authors":"D. Patiyoot, S. Shepherd","doi":"10.1109/ICATM.1998.688163","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688163","url":null,"abstract":"With the growing acceptance of ATM as the standard for broadband networking and the increasing importance of wireless devices, it has become appropriate to extend ATM application to wireless platforms. Adding a wireless network to existing wired networks creates a new set of problems. Security functions have to be reconsidered since wired network security does not account for the open medium, mobile roaming. A necessary foundation for securing a network is the ability to authenticate entities. There is a need to authenticate users of the system so that the resources will not be misused by nonsubscribers. After authentication by a suitable protocol, two parties involved in communications should be entitled to believe that they are communicating with each other and not with intruders. Good authentication is that which allows entities to provide evidence that they know a particular secret without revealing the secret. It should not provide any information to impersonators or eavesdroppers while being authenticated. In mobile networks, normally secret-key cryptography is used for authentication. In this paper, both secret-key and public-key cryptography are used in wireless ATM networks.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124971657","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 : 1998-06-22DOI: 10.1109/ICATM.1998.688198
E. Stipidis, S. Li, E. T. Powner
In the information society we live in, offices are becoming our "second home". A comfortable and secure environment for people in the work place, as well as increasing efficiency and productivity, indicate a growing interest in the integration of information technologies and telecommunications in intelligent buildings. These needs are engaged in large scale distributed environments and a solution for this integration is a type of network that can be standardised throughout the world. This article shows how ATM, being currently the most effective B-ISDN protocol for WAN and LAN, could meet all the requirements for fully integrated systems in intelligent buildings.
{"title":"Intelligent building systems: system integration using ATM","authors":"E. Stipidis, S. Li, E. T. Powner","doi":"10.1109/ICATM.1998.688198","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688198","url":null,"abstract":"In the information society we live in, offices are becoming our \"second home\". A comfortable and secure environment for people in the work place, as well as increasing efficiency and productivity, indicate a growing interest in the integration of information technologies and telecommunications in intelligent buildings. These needs are engaged in large scale distributed environments and a solution for this integration is a type of network that can be standardised throughout the world. This article shows how ATM, being currently the most effective B-ISDN protocol for WAN and LAN, could meet all the requirements for fully integrated systems in intelligent buildings.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129872966","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 : 1998-06-22DOI: 10.1109/ICATM.1998.688185
S. Li, J.-G. Chen, N. Ansari
The output-buffered switching architecture with its ability to offer high throughput, guaranteed delay and fairness, is not practical owing to its lack of scalability, i.e., the memory size, speed, and control logic have to be scaled up proportionally to the number of input links, thus becoming infeasible for large switches. The commercial and research trend is to adopt an architecture with input buffering which is scalable, but yields lower throughput and lacks the quality-of-service features such as delay bound and fairness. Although the problem of low throughput owing to head of line blocking in input-buffered switches can be resolved by adopting per-output-port queueing in each input port, the contention among input ports still limits the throughput. Existing schedulers designed for input-buffered switches attempt to improve throughput by imposing back pressure to the contending cells, and scheduling cells free of contention for transmission, at the expense of delay and fairness. In this paper, we have modeled and analyzed the back pressure with an independent Bernoulli traffic load, and we have shown that there is a high probability of back pressure occurring under loaded traffic. We have also derived the average queue length at the input buffer. To address the above issues in input-buffered switches, we proposed a new algorithm, referred to as min-max fair input queueing (MFIQ), which minimizes the additional delay caused by back pressure and at the same time provides fair service among competing sessions.
{"title":"Fair queueing for input-buffered switches with back pressure","authors":"S. Li, J.-G. Chen, N. Ansari","doi":"10.1109/ICATM.1998.688185","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688185","url":null,"abstract":"The output-buffered switching architecture with its ability to offer high throughput, guaranteed delay and fairness, is not practical owing to its lack of scalability, i.e., the memory size, speed, and control logic have to be scaled up proportionally to the number of input links, thus becoming infeasible for large switches. The commercial and research trend is to adopt an architecture with input buffering which is scalable, but yields lower throughput and lacks the quality-of-service features such as delay bound and fairness. Although the problem of low throughput owing to head of line blocking in input-buffered switches can be resolved by adopting per-output-port queueing in each input port, the contention among input ports still limits the throughput. Existing schedulers designed for input-buffered switches attempt to improve throughput by imposing back pressure to the contending cells, and scheduling cells free of contention for transmission, at the expense of delay and fairness. In this paper, we have modeled and analyzed the back pressure with an independent Bernoulli traffic load, and we have shown that there is a high probability of back pressure occurring under loaded traffic. We have also derived the average queue length at the input buffer. To address the above issues in input-buffered switches, we proposed a new algorithm, referred to as min-max fair input queueing (MFIQ), which minimizes the additional delay caused by back pressure and at the same time provides fair service among competing sessions.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132641903","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 : 1998-06-22DOI: 10.1109/ICATM.1998.688192
K. Lau, M.H. Lee, K. Ngan, G. Rogers
We present a software prototype of a cell-loss resilient scheme for data with different priorities transmitted over ATM networks. The levels of protection provided by the scheme depend on the priority level assigned to each data segment by the user. The priority level is a function of the expected cell loss rate during transmission. The developed prototype can sustain a continuous throughput between transmitting and receiving sides at tens of kilobytes per second. Its immediate application would be useful for the real-time transmission of a scalable video stream which can be efficiently split into multilayers with different priorities.
{"title":"Priority encoding of video data over ATM","authors":"K. Lau, M.H. Lee, K. Ngan, G. Rogers","doi":"10.1109/ICATM.1998.688192","DOIUrl":"https://doi.org/10.1109/ICATM.1998.688192","url":null,"abstract":"We present a software prototype of a cell-loss resilient scheme for data with different priorities transmitted over ATM networks. The levels of protection provided by the scheme depend on the priority level assigned to each data segment by the user. The priority level is a function of the expected cell loss rate during transmission. The developed prototype can sustain a continuous throughput between transmitting and receiving sides at tens of kilobytes per second. Its immediate application would be useful for the real-time transmission of a scalable video stream which can be efficiently split into multilayers with different priorities.","PeriodicalId":257298,"journal":{"name":"1998 1st IEEE International Conference on ATM. ICATM'98","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123859338","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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