One approach to network emulation involves simulating a virtual network with a real-time network simulator and providing an I/O interface that enables interaction between real hosts and the virtual network. This allows real protocols and applications to be tested in a controlled and repeatable environment. To reflect conditions of large networks such as the Internet it is important that the emulation environment be scalable. This paper examines improvements in scalability of the virtual network achieved through the use of parallel discrete event simulation and simulation abstraction. Using just parallel simulation techniques, real-time emulation performance of nearly 50 million packet transmissions per second is achieved on 128 processors for a network model consisting of about 20,000 nodes. Using both parallel simulation and abstraction techniques, real-time emulation performance of nearly 500 million packet transmissions per second is achieved on 128 processors for a network model consisting of about 200,000 nodes.
{"title":"Improving scalability of network emulation through parallelism and abstraction","authors":"C. Kiddle, R. Simmonds, B. Unger","doi":"10.1109/ANSS.2005.26","DOIUrl":"https://doi.org/10.1109/ANSS.2005.26","url":null,"abstract":"One approach to network emulation involves simulating a virtual network with a real-time network simulator and providing an I/O interface that enables interaction between real hosts and the virtual network. This allows real protocols and applications to be tested in a controlled and repeatable environment. To reflect conditions of large networks such as the Internet it is important that the emulation environment be scalable. This paper examines improvements in scalability of the virtual network achieved through the use of parallel discrete event simulation and simulation abstraction. Using just parallel simulation techniques, real-time emulation performance of nearly 50 million packet transmissions per second is achieved on 128 processors for a network model consisting of about 20,000 nodes. Using both parallel simulation and abstraction techniques, real-time emulation performance of nearly 500 million packet transmissions per second is achieved on 128 processors for a network model consisting of about 200,000 nodes.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125885705","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}
Wentong Cai, S. Turner, Suiping Zhou, Junhu Wei, Wenbo Zong
An important issue in distributed real-time simulation is to reduce the amount of data transmitted amongst distributed simulation nodes so that the state updates of simulation entities can be sent to other simulation nodes in a timely manner. To address this issue, we have previously proposed a consistency model to determine the update interval of entities based on their relative importance, a utility model to compute the relative importance of entities, and a flexible state update mechanism to ensure updating within these intervals and to balance the number of updates in each simulation frame. In this paper, we focus on the performance evaluation of these timely state update mechanisms. Using a battlefield benchmark, the performance is evaluated in terms of the total amount of data exchanged, the number of simulation frames skipped, and the number of go-through-accidents occurring during the simulation. The performance results indicate that the mechanisms can significantly reduce the bandwidth requirements while maintaining or even improving the consistency of the simulation.
{"title":"Performance evaluation of a bandwidth requirements reduction technique based on timely state update","authors":"Wentong Cai, S. Turner, Suiping Zhou, Junhu Wei, Wenbo Zong","doi":"10.1109/ANSS.2005.35","DOIUrl":"https://doi.org/10.1109/ANSS.2005.35","url":null,"abstract":"An important issue in distributed real-time simulation is to reduce the amount of data transmitted amongst distributed simulation nodes so that the state updates of simulation entities can be sent to other simulation nodes in a timely manner. To address this issue, we have previously proposed a consistency model to determine the update interval of entities based on their relative importance, a utility model to compute the relative importance of entities, and a flexible state update mechanism to ensure updating within these intervals and to balance the number of updates in each simulation frame. In this paper, we focus on the performance evaluation of these timely state update mechanisms. Using a battlefield benchmark, the performance is evaluated in terms of the total amount of data exchanged, the number of simulation frames skipped, and the number of go-through-accidents occurring during the simulation. The performance results indicate that the mechanisms can significantly reduce the bandwidth requirements while maintaining or even improving the consistency of the simulation.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"241 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116053044","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 factors influencing spread of Lyme disease are often studied using computer-based simulations and spatially explicit models. However, simulating large and complex models is a time consuming task, even when parallel simulation techniques are employed. In an endeavor to accelerate such simulations, an alternative approach involving dynamic (i.e., during simulation) changes to spatial resolution of the model via a novel methodology called dynamic component substitution (DCS) is proposed. Changes to the resolution are performed such that the total number of interactions between the entities in the model is optimized, thereby improving overall performance but introducing minor (< /spl plusmn/1%) deviations in the results. This paper explores the effectiveness and issues involved in applying DCS to accelerate sequential and parallel simulations of spatially explicit Lyme disease models. The paper also presents a brief description of the simulation environment along with empirical results. Our experiments indicate that performance improvements can be obtained using the proposed approach.
{"title":"Accelerating spatially explicit simulations of spread of Lyme disease","authors":"D. Rao, P. Wilsey","doi":"10.1109/ANSS.2005.10","DOIUrl":"https://doi.org/10.1109/ANSS.2005.10","url":null,"abstract":"The factors influencing spread of Lyme disease are often studied using computer-based simulations and spatially explicit models. However, simulating large and complex models is a time consuming task, even when parallel simulation techniques are employed. In an endeavor to accelerate such simulations, an alternative approach involving dynamic (i.e., during simulation) changes to spatial resolution of the model via a novel methodology called dynamic component substitution (DCS) is proposed. Changes to the resolution are performed such that the total number of interactions between the entities in the model is optimized, thereby improving overall performance but introducing minor (< /spl plusmn/1%) deviations in the results. This paper explores the effectiveness and issues involved in applying DCS to accelerate sequential and parallel simulations of spatially explicit Lyme disease models. The paper also presents a brief description of the simulation environment along with empirical results. Our experiments indicate that performance improvements can be obtained using the proposed approach.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129332953","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 random trip model was recently proposed as a generic mobility model that contains many particular mobility models, including the widely-known random waypoint and random walks, and accommodates more realistic scenarios. The probability distribution of the movement of a mobile in all these models typically varies with time and converges to a "steady state" distribution (viz- stationary distribution), whenever the last exists. Protocol performance during this transient phase and in steady-state may differ significantly. This justifies the interest in perfect sampling of the initial node mobility state, so that the simulation of the node mobility is perfect, i.e. it is in steady state throughout a simulation. In this work, we describe implementation of the perfect sampling for some random trip models. Our tool produces a perfect sample of the node mobility state, which is then used as input to the widely-used ns-2 network simulator. We further show some simulation results for a particular random trip mobility model, based on a real-world road map. The performance metrics that we consider include various node communication properties and their evolution with time. The results demonstrate difference between transient and steady-state phases and that the transient phase can be long lasting (in the order of a typical simulation duration), if the initial state is drawn from a non steady-state distribution. The results give strong arguments in favor to running perfect simulations. Our perfect sampling tool is available to public at: http://www.cs.rice.edu//spl sim/santa/research/mobility.
{"title":"Perfect simulations for random trip mobility models","authors":"Santashil PalChaudhuri, J. Boudec, M. Vojnović","doi":"10.1109/ANSS.2005.33","DOIUrl":"https://doi.org/10.1109/ANSS.2005.33","url":null,"abstract":"The random trip model was recently proposed as a generic mobility model that contains many particular mobility models, including the widely-known random waypoint and random walks, and accommodates more realistic scenarios. The probability distribution of the movement of a mobile in all these models typically varies with time and converges to a \"steady state\" distribution (viz- stationary distribution), whenever the last exists. Protocol performance during this transient phase and in steady-state may differ significantly. This justifies the interest in perfect sampling of the initial node mobility state, so that the simulation of the node mobility is perfect, i.e. it is in steady state throughout a simulation. In this work, we describe implementation of the perfect sampling for some random trip models. Our tool produces a perfect sample of the node mobility state, which is then used as input to the widely-used ns-2 network simulator. We further show some simulation results for a particular random trip mobility model, based on a real-world road map. The performance metrics that we consider include various node communication properties and their evolution with time. The results demonstrate difference between transient and steady-state phases and that the transient phase can be long lasting (in the order of a typical simulation duration), if the initial state is drawn from a non steady-state distribution. The results give strong arguments in favor to running perfect simulations. Our perfect sampling tool is available to public at: http://www.cs.rice.edu//spl sim/santa/research/mobility.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126663905","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}
A. Boukerche, Nathan J. McGraw, Caron Dzermajko, Kaiyuan Lu
In a large-scale distributed simulation, participating federates receive and send messages to share state data and update subscription and publication regions. The focus of data distribution management (DDM), a high level architecture (HLA) run-time infrastructure (RTI) service, is limiting and controlling the volume of data, regarding simulated entities, exchanged between participating hosts. One of the key factors in many large-scale distributed simulations is the ability to see or be seen by other participants in the simulation. Several DDM methods have been introduced, but time performance, message volume and resource usage continue to be factors in the practical application of these methods. In an effort to offer a more efficient and more scalable solution to DDM, we propose an algorithm which we refer to as grid-filtered region-based DDM, that utilizes a grid overlay on the virtual space, determines the percentage of grid covered by the subscription or publication region and further filters, based on a percentage threshold, using a matching technique, like that of the region-based DDM scheme. We present the implementation details of our scheme and report on our set of experiments we have carried out to evaluate its performance.
{"title":"Grid-filtered region-based data distribution management in large-scale distributed simulation systems","authors":"A. Boukerche, Nathan J. McGraw, Caron Dzermajko, Kaiyuan Lu","doi":"10.1109/ANSS.2005.23","DOIUrl":"https://doi.org/10.1109/ANSS.2005.23","url":null,"abstract":"In a large-scale distributed simulation, participating federates receive and send messages to share state data and update subscription and publication regions. The focus of data distribution management (DDM), a high level architecture (HLA) run-time infrastructure (RTI) service, is limiting and controlling the volume of data, regarding simulated entities, exchanged between participating hosts. One of the key factors in many large-scale distributed simulations is the ability to see or be seen by other participants in the simulation. Several DDM methods have been introduced, but time performance, message volume and resource usage continue to be factors in the practical application of these methods. In an effort to offer a more efficient and more scalable solution to DDM, we propose an algorithm which we refer to as grid-filtered region-based DDM, that utilizes a grid overlay on the virtual space, determines the percentage of grid covered by the subscription or publication region and further filters, based on a percentage threshold, using a matching technique, like that of the region-based DDM scheme. We present the implementation details of our scheme and report on our set of experiments we have carried out to evaluate its performance.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130121277","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}
There has been recent interest in employing unified pricing schemes for supporting both QoS and best-effort traffic within multiservice networks. This paper presents an analytical approach for the design and analysis of this class of network pricing control. In particular, we propose an approximation method to estimate overall user value arising from all traffic types, given the routes for QoS traffic. Our approach considers admission control as both a resource allocation issue for QoS traffic, and a pricing control decision for best-effort and QoS traffic. We show how to convert the price-based admission control decision to a resource-based blocking problem. We also present the numerical results of performance analysis for multiservice networks using our proposed approximation method. Our approach can be used to predict the performance and parameter settings for a wide range of combined QoS and best-effort pricing schemes.
{"title":"Performance analysis for multi-service networks with congestion-based pricing for QoS traffic","authors":"Woan Sun Chang, R. Simon","doi":"10.1109/ANSS.2005.34","DOIUrl":"https://doi.org/10.1109/ANSS.2005.34","url":null,"abstract":"There has been recent interest in employing unified pricing schemes for supporting both QoS and best-effort traffic within multiservice networks. This paper presents an analytical approach for the design and analysis of this class of network pricing control. In particular, we propose an approximation method to estimate overall user value arising from all traffic types, given the routes for QoS traffic. Our approach considers admission control as both a resource allocation issue for QoS traffic, and a pricing control decision for best-effort and QoS traffic. We show how to convert the price-based admission control decision to a resource-based blocking problem. We also present the numerical results of performance analysis for multiservice networks using our proposed approximation method. Our approach can be used to predict the performance and parameter settings for a wide range of combined QoS and best-effort pricing schemes.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116955386","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 proposes a kernel for the distributed simulation of real-time systems modelled by Merlin and Farber's time Petri nets (TPN). The realization depends on temporal uncertainty time warp (TUTW), a novel time warp algorithm capable of exploiting temporal uncertainty in general optimistic simulations. A key feature of the application rests on the fact that TPN models naturally exhibit a certain degree of temporal uncertainty which the TUTW control engine can exploit to achieve good speedup without impairing accuracy of the simulation output. Usefulness of the achieved TUTW/TPN kernel is demonstrated by simulation experiments on a real-time system example.
{"title":"Exploiting temporal uncertainty in the distributed simulation of time Petri nets","authors":"F. Cicirelli, A. Furfaro, L. Nigro","doi":"10.1109/ANSS.2005.20","DOIUrl":"https://doi.org/10.1109/ANSS.2005.20","url":null,"abstract":"This paper proposes a kernel for the distributed simulation of real-time systems modelled by Merlin and Farber's time Petri nets (TPN). The realization depends on temporal uncertainty time warp (TUTW), a novel time warp algorithm capable of exploiting temporal uncertainty in general optimistic simulations. A key feature of the application rests on the fact that TPN models naturally exhibit a certain degree of temporal uncertainty which the TUTW control engine can exploit to achieve good speedup without impairing accuracy of the simulation output. Usefulness of the achieved TUTW/TPN kernel is demonstrated by simulation experiments on a real-time system example.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128330224","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}
A wireless sensor network is a special kind of ad hoc network where the nodes can sense, actuate, compute and communicate with each other using point-to-point multi-hop communication. Sensor networks can be used in a wide range of applications, such as environmental monitoring and industrial applications. Despite their potential applications, such networks have particular features imposed by resource restrictions, such as low computational power, reduced bandwidth and specially limited power source. Nowadays, real wireless sensor networks infrastructures are still very expensive. Therefore, most of the evaluations of new protocols are being made through simulation tools. The objective of this work is to verify the applicability of using cellular automata to simulate some aspects of sensor networks. A simulator has been developed to evaluate an algorithm for a very common problem in sensor networks: the topology control. The solution presented is based on the geographical position and the operational states of the sensor nodes. The obtained results indicate that cellular automata can be used with success to simulate large wireless sensor networks.
{"title":"Simulating large wireless sensor networks using cellular automata","authors":"Renan Cunha, A. P. Silva, A. Loureiro, L. B. Ruiz","doi":"10.1109/ANSS.2005.40","DOIUrl":"https://doi.org/10.1109/ANSS.2005.40","url":null,"abstract":"A wireless sensor network is a special kind of ad hoc network where the nodes can sense, actuate, compute and communicate with each other using point-to-point multi-hop communication. Sensor networks can be used in a wide range of applications, such as environmental monitoring and industrial applications. Despite their potential applications, such networks have particular features imposed by resource restrictions, such as low computational power, reduced bandwidth and specially limited power source. Nowadays, real wireless sensor networks infrastructures are still very expensive. Therefore, most of the evaluations of new protocols are being made through simulation tools. The objective of this work is to verify the applicability of using cellular automata to simulate some aspects of sensor networks. A simulator has been developed to evaluate an algorithm for a very common problem in sensor networks: the topology control. The solution presented is based on the geographical position and the operational states of the sensor nodes. The obtained results indicate that cellular automata can be used with success to simulate large wireless sensor networks.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125574619","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}
A. Washington, Chih-Chieh Hsu, H. Perros, M. Devetsikiotis
We consider a traffic-groomed optical network consisting of N nodes arranged in tandem. This optical network is modeled by a tandem queueing network of multirate loss queues with simultaneous resource possession. Two approximation methods are proposed for the analysis of this queueing network assuming that the total number of servers in each multi-rate loss queue is very large. The accuracy of these two approximation methods as well as the accuracy of the familiar link independence algorithm is verified by simulation. As an additional contribution, the simulation estimates have been obtained using adaptive rare-event simulation techniques based on importance sampling. This is because call blocking probabilities tend to be very small and it is not feasible to estimate them using standard simulation techniques.
{"title":"Approximation techniques for the analysis of large traffic-groomed tandem optical networks","authors":"A. Washington, Chih-Chieh Hsu, H. Perros, M. Devetsikiotis","doi":"10.1109/ANSS.2005.13","DOIUrl":"https://doi.org/10.1109/ANSS.2005.13","url":null,"abstract":"We consider a traffic-groomed optical network consisting of N nodes arranged in tandem. This optical network is modeled by a tandem queueing network of multirate loss queues with simultaneous resource possession. Two approximation methods are proposed for the analysis of this queueing network assuming that the total number of servers in each multi-rate loss queue is very large. The accuracy of these two approximation methods as well as the accuracy of the familiar link independence algorithm is verified by simulation. As an additional contribution, the simulation estimates have been obtained using adaptive rare-event simulation techniques based on importance sampling. This is because call blocking probabilities tend to be very small and it is not feasible to estimate them using standard simulation techniques.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"224 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122605580","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}
Service disciplines that approximate GPS have had a lot of success satisfying QoS isolation among connections in integrated services networks. In the past years, several of such disciplines were developed. However, to maintain a delay little bigger than GPS, with a fair throughput and a good worst-case fairness while reducing computational overhead is a big challenge. LFVC appears to be the first service discipline that optimizes these factors. This motivated us to implement an original LFVC model in the context of an ATM network model, originally developed to trustworthily evaluate QoS in ATM networks. LFVC expands this model and improves its quality, since LFVC is capable to isolate traffic and capture service differences among connections. In addition, LFVC interacts with other models of this model set, producing better simulation results. The paper also presents a model validation and a performance evaluation of the LFVC scheduler.
{"title":"Modeling and simulation of a LFVC scheduler","authors":"A. Alberti","doi":"10.1109/ANSS.2005.30","DOIUrl":"https://doi.org/10.1109/ANSS.2005.30","url":null,"abstract":"Service disciplines that approximate GPS have had a lot of success satisfying QoS isolation among connections in integrated services networks. In the past years, several of such disciplines were developed. However, to maintain a delay little bigger than GPS, with a fair throughput and a good worst-case fairness while reducing computational overhead is a big challenge. LFVC appears to be the first service discipline that optimizes these factors. This motivated us to implement an original LFVC model in the context of an ATM network model, originally developed to trustworthily evaluate QoS in ATM networks. LFVC expands this model and improves its quality, since LFVC is capable to isolate traffic and capture service differences among connections. In addition, LFVC interacts with other models of this model set, producing better simulation results. The paper also presents a model validation and a performance evaluation of the LFVC scheduler.","PeriodicalId":270527,"journal":{"name":"38th Annual Simulation Symposium","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116862411","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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