Pub Date : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000142
Hisham H. Muhammad, M. Barcellos
This paper discusses the design and implementation! of Simm-cast, an object-oriented framework for network simulation with specific support for group communication. The design of the framework is focused towards simplicity and extensibility. The aim is to allow a spectrum of experiments ranging from evaluation of abstract group communication models to simulation of more detailed multicast protocol behavior Simm-cast employs a process-based discrete-event model on which building blocks are combined and extended in order to create new simulation environments. Network parameters are given in terms of numeric distributions (fixed or probabilistic), which can be replaced without recompilation. This extensive use of numeric distributions combined to the extendible framework structure allow an abstract experiment to evolve into a detailed one by progressively increasing the level of detail and sources of non-determinism of the constituting blocks.
{"title":"Simulating group communication protocols through an object-oriented framework","authors":"Hisham H. Muhammad, M. Barcellos","doi":"10.1109/SIMSYM.2002.1000142","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000142","url":null,"abstract":"This paper discusses the design and implementation! of Simm-cast, an object-oriented framework for network simulation with specific support for group communication. The design of the framework is focused towards simplicity and extensibility. The aim is to allow a spectrum of experiments ranging from evaluation of abstract group communication models to simulation of more detailed multicast protocol behavior Simm-cast employs a process-based discrete-event model on which building blocks are combined and extended in order to create new simulation environments. Network parameters are given in terms of numeric distributions (fixed or probabilistic), which can be replaced without recompilation. This extensive use of numeric distributions combined to the extendible framework structure allow an abstract experiment to evolve into a detailed one by progressively increasing the level of detail and sources of non-determinism of the constituting blocks.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121675391","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 : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000153
Hélio A. S. Lima Filho, C. Hirata
The process of solving a problem involves several tasks. In many situations, modeling is regarded as the key task for solving the problem. The modeling task includes an important sub-task namely model representation. Model representation results into a specification that can be communicated to the participants and serves as the basis for discussion in further tasks of the process. The modeling and its related tasks such as accreditation, verification, validation, and design for tests and experimentation require to meet the participants. It is understood that these meetings are time consuming and expensive. This paper proposes a collaborative tool to help the modelers to represent the model. The tool considers that the model can be represented using hierarchical graphs. The tool is based on a collaborative computer system, named groupware, and uses the concept of full replication. We show some examples to illustrate the use of the tool and discuss some issues related to collaborative tools such as concurrency control, awareness, and performance.
{"title":"GroupGraph: a collaborative hierarchical graph editor based on the Internet","authors":"Hélio A. S. Lima Filho, C. Hirata","doi":"10.1109/SIMSYM.2002.1000153","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000153","url":null,"abstract":"The process of solving a problem involves several tasks. In many situations, modeling is regarded as the key task for solving the problem. The modeling task includes an important sub-task namely model representation. Model representation results into a specification that can be communicated to the participants and serves as the basis for discussion in further tasks of the process. The modeling and its related tasks such as accreditation, verification, validation, and design for tests and experimentation require to meet the participants. It is understood that these meetings are time consuming and expensive. This paper proposes a collaborative tool to help the modelers to represent the model. The tool considers that the model can be represented using hierarchical graphs. The tool is based on a collaborative computer system, named groupware, and uses the concept of full replication. We show some examples to illustrate the use of the tool and discuss some issues related to collaborative tools such as concurrency control, awareness, and performance.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115137016","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 : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000176
F. I. Massetto, W. L. Souza, S. Zorzo
This article presents an approach and tool for specification simulations accomplished in the formal description technique (FDT) enhancements to language of temporal ordering specification (E-LOTOS). Based on the defined inference rules for the E-LOTOS operators, the tool offers resources for interactive simulation, enabling the user to monitor the specification behavior. To illustrate the use of the approach and tool, a multimedia application design, specification and simulation is discussed.
{"title":"Simulator for E-LOTOS specifications","authors":"F. I. Massetto, W. L. Souza, S. Zorzo","doi":"10.1109/SIMSYM.2002.1000176","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000176","url":null,"abstract":"This article presents an approach and tool for specification simulations accomplished in the formal description technique (FDT) enhancements to language of temporal ordering specification (E-LOTOS). Based on the defined inference rules for the E-LOTOS operators, the tool offers resources for interactive simulation, enabling the user to monitor the specification behavior. To illustrate the use of the approach and tool, a multimedia application design, specification and simulation is discussed.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124234611","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 : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000166
Alejandro J. Troccoli, J. Ameghino, F. Iñón, Gabriel A. Wainer
Cell-DEVS is an extension to the DEVS formalism that allows the definition of cellular models. Complex physical systems can be defined using simple rules, reducing the development. We present the definition of a model of flow injection using Cell-DEVS. The simulation validation results showed a margin of error within the expected values for the experiment, showing how to employ the formalism in analyzing physical systems.
{"title":"A flow injection model using Cell-DEVS","authors":"Alejandro J. Troccoli, J. Ameghino, F. Iñón, Gabriel A. Wainer","doi":"10.1109/SIMSYM.2002.1000166","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000166","url":null,"abstract":"Cell-DEVS is an extension to the DEVS formalism that allows the definition of cellular models. Complex physical systems can be defined using simple rules, reducing the development. We present the definition of a model of flow injection using Cell-DEVS. The simulation validation results showed a margin of error within the expected values for the experiment, showing how to employ the formalism in analyzing physical systems.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130904123","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 : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000168
Rajarishi Sinha, C. Paredis, P. Khosla
We present a simulation and design framework for simultaneously designing and modeling electromechanical systems. By instantiating component objects and connecting them to each other via ports, a designer can configure complex systems. This configuration information is then used to automatically generate a corresponding system-level simulation model. The building block of our framework is the component object. It encapsulates design data and behavioral models and their inter-relationships. Component objects are composed into systems by connecting their ports. However, when converting a system configuration into a corresponding simulation model, the corresponding models for the component objects do not capture the physical phenomena at the component interfaces the interactions. To obtain an accurate composition, the interaction dynamics must also be captured in behavioral models. In this paper, we introduce the concept of an interaction model that captures the dynamics of the interaction. When two ports are connected, there is an intended interaction between the two components. For composition of component objects to work, an interaction model must be introduced between each pair of connected behavioral models. We illustrate these ideas using an example.
{"title":"Behavioral model composition in simulation-based design","authors":"Rajarishi Sinha, C. Paredis, P. Khosla","doi":"10.1109/SIMSYM.2002.1000168","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000168","url":null,"abstract":"We present a simulation and design framework for simultaneously designing and modeling electromechanical systems. By instantiating component objects and connecting them to each other via ports, a designer can configure complex systems. This configuration information is then used to automatically generate a corresponding system-level simulation model. The building block of our framework is the component object. It encapsulates design data and behavioral models and their inter-relationships. Component objects are composed into systems by connecting their ports. However, when converting a system configuration into a corresponding simulation model, the corresponding models for the component objects do not capture the physical phenomena at the component interfaces the interactions. To obtain an accurate composition, the interaction dynamics must also be captured in behavioral models. In this paper, we introduce the concept of an interaction model that captures the dynamics of the interaction. When two ports are connected, there is an intended interaction between the two components. For composition of component objects to work, an interaction model must be introduced between each pair of connected behavioral models. We illustrate these ideas using an example.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"548 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127023517","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 : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000170
Karl-Johan Grinnemo, A. Brunström
Since TCP is considered unsuitable for the majority of the emerging multimedia applications, these applications primarily use UDP transport together with proprietary congestion control schemes that have better jitter and throughput characteristics. A common problem with these congestion control schemes is that they often exhibit a TCP-unfriendly and unfair behavior As the number of applications that uses this kind of schemes increases, this could become a serious threat to the stability and performance of the Internet. In an attempt to make TCP a viable alternative to some best-effort multimedia applications, we have proposed an extension to TCP - PRTP-ECN. The performance of PRTP-ECN has been compared with TCP in an extensive factorial simulation experiment. This paper gives a detailed description of this simulation experiment with an emphasis on its statistical design and analysis. The analysis of the experiment includes, among other things, a series of ANOVA tests. These tests indicate that PRTP-ECN gives significant reductions in average inter arrival jitter while at the same time leads to improvements in average throughput and goodput, and better link utilization. In addition, the analysis suggests that PRTP-ECN is almost as fair as TCP and exhibits a TCP-friendly behavior.
{"title":"A simulation based performance analysis of a TCP extension for best-effort multimedia applications","authors":"Karl-Johan Grinnemo, A. Brunström","doi":"10.1109/SIMSYM.2002.1000170","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000170","url":null,"abstract":"Since TCP is considered unsuitable for the majority of the emerging multimedia applications, these applications primarily use UDP transport together with proprietary congestion control schemes that have better jitter and throughput characteristics. A common problem with these congestion control schemes is that they often exhibit a TCP-unfriendly and unfair behavior As the number of applications that uses this kind of schemes increases, this could become a serious threat to the stability and performance of the Internet. In an attempt to make TCP a viable alternative to some best-effort multimedia applications, we have proposed an extension to TCP - PRTP-ECN. The performance of PRTP-ECN has been compared with TCP in an extensive factorial simulation experiment. This paper gives a detailed description of this simulation experiment with an emphasis on its statistical design and analysis. The analysis of the experiment includes, among other things, a series of ANOVA tests. These tests indicate that PRTP-ECN gives significant reductions in average inter arrival jitter while at the same time leads to improvements in average throughput and goodput, and better link utilization. In addition, the analysis suggests that PRTP-ECN is almost as fair as TCP and exhibits a TCP-friendly behavior.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132353524","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 : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000093
Sébastien Nussbaum, James E. Smith
Statistical simulation is driven by a stream of randomly generated instructions, based on statistics collected during a single detailed simulation. This method can give accurate performance estimates within minutes, allowing a large design space to be simulated quickly. Prior work has applied this technique to superscalar processors. We evaluate the extension of statistical simulation to symmetric multiprocessing systems. Key program parameters are identified and program statistics are collected during detailed simulations for both multiprogrammed workloads (SpecInt) and parallel scientific workload (Splash-2). The accuracy of statistical simulation is evaluated at different levels of model detail, and it is shown that for multiprogrammed workloads a 10% average error can be achieved, and for parallel benchmark programs 15% average error can be achieved.
{"title":"Statistical simulation of symmetric multiprocessor systems","authors":"Sébastien Nussbaum, James E. Smith","doi":"10.1109/SIMSYM.2002.1000093","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000093","url":null,"abstract":"Statistical simulation is driven by a stream of randomly generated instructions, based on statistics collected during a single detailed simulation. This method can give accurate performance estimates within minutes, allowing a large design space to be simulated quickly. Prior work has applied this technique to superscalar processors. We evaluate the extension of statistical simulation to symmetric multiprocessing systems. Key program parameters are identified and program statistics are collected during detailed simulations for both multiprogrammed workloads (SpecInt) and parallel scientific workload (Splash-2). The accuracy of statistical simulation is evaluated at different levels of model detail, and it is shown that for multiprogrammed workloads a 10% average error can be achieved, and for parallel benchmark programs 15% average error can be achieved.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129209338","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 : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000158
A. P. Silva, G. Mateus
The data traffic in wireless networks for the third generation (3G) mobile telecommunication systems should take into account a variety of services (voice, data, video) and environments (e.g.: private, outdoors, indoors) as well as the user mobility behavior. A good evaluation of measures of performance can help a system designer to make strategic decisions concerning cell size and the number of channel frequencies allocated to each cell. We present an analysis of data services in third generation mobile telecommunication networks based on simulation. In addition, we illustrate the need for a simulation in order to characterize the mix of several traffic types for capacity and quality of service (QoS) planning. We use the distributions heavy tailed Weibull and Pareto to simulate respectively, the data traffic and the resource occupation time for data service. Finally, we also comment on some simulation results of third generation services where we analyze the QoS parameters of a mobile network, such as channel occupation time, handoff, new call blocking probabilities and traffic in Erlangs.
{"title":"Performance analysis for data service in third generation mobile telecommunication networks","authors":"A. P. Silva, G. Mateus","doi":"10.1109/SIMSYM.2002.1000158","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000158","url":null,"abstract":"The data traffic in wireless networks for the third generation (3G) mobile telecommunication systems should take into account a variety of services (voice, data, video) and environments (e.g.: private, outdoors, indoors) as well as the user mobility behavior. A good evaluation of measures of performance can help a system designer to make strategic decisions concerning cell size and the number of channel frequencies allocated to each cell. We present an analysis of data services in third generation mobile telecommunication networks based on simulation. In addition, we illustrate the need for a simulation in order to characterize the mix of several traffic types for capacity and quality of service (QoS) planning. We use the distributions heavy tailed Weibull and Pareto to simulate respectively, the data traffic and the resource occupation time for data service. Finally, we also comment on some simulation results of third generation services where we analyze the QoS parameters of a mobile network, such as channel occupation time, handoff, new call blocking probabilities and traffic in Erlangs.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117038550","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 : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000165
J. Clymer
A Complex Adaptive System (CAS) is a network of communicating, intelligent agents where each agent adapts its behavior in order to collaborate with other agents to achieve overall system goals. Further, the overall system often exhibits emergent behavior that cannot be achieved by any proper subset of agents alone. A graphical simulation library called Operational Evaluation Modeling for Context-Sensitive Systems (OpEMCSS) has been developed to simulate complex systems, including CAS. This simulation library includes a Classifier Event Action block that is a forward chaining, expert system controller. The Classifier Event Action block can implement both crisp and fuzzy rules. A network of traffic light controller agents, one at each intersection, is simulated for a city traffic grid. Each traffic controller agent uses a fuzzy classifier block to make decisions about traffic light timing in order to minimize local vehicle wait time. Out of the co-evolutionary interaction of these agents, emerges the global minimization of vehicle wait time in the network.
{"title":"Simulation of a vehicle traffic control network using a fuzzy classifier system","authors":"J. Clymer","doi":"10.1109/SIMSYM.2002.1000165","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000165","url":null,"abstract":"A Complex Adaptive System (CAS) is a network of communicating, intelligent agents where each agent adapts its behavior in order to collaborate with other agents to achieve overall system goals. Further, the overall system often exhibits emergent behavior that cannot be achieved by any proper subset of agents alone. A graphical simulation library called Operational Evaluation Modeling for Context-Sensitive Systems (OpEMCSS) has been developed to simulate complex systems, including CAS. This simulation library includes a Classifier Event Action block that is a forward chaining, expert system controller. The Classifier Event Action block can implement both crisp and fuzzy rules. A network of traffic light controller agents, one at each intersection, is simulated for a city traffic grid. Each traffic controller agent uses a fuzzy classifier block to make decisions about traffic light timing in order to minimize local vehicle wait time. Out of the co-evolutionary interaction of these agents, emerges the global minimization of vehicle wait time in the network.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115619255","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 : 2002-04-14DOI: 10.1109/SIMSYM.2002.1000140
Kenneth J. Christensen
CSIM18 simulation models are often built as Microsoft Windows console-mode programs. A tool named REMOTE was developed to enable automatic, remote execution of CSIM18 models (and of other console mode programs) in a Windows environment. A master PC distributes the programs to remote PCs and collects the output files as the remote model executions complete. The status of remotely executing models can be viewed at the master. The REMOTE tool utilizes idle non-dedicated PC CPU cycles during nights and weekends to speed-up the model execution phase of a large modeling project. The REMOTE executable can be distributed via email attachment and does not need any special installation or configuration. REMOTE is currently being used in an ongoing investigation of new variable-length packet switch architectures. REMOTE is freely available from the author.
{"title":"REMOTE: a tool for automatic remote execution of CSIM simulation models","authors":"Kenneth J. Christensen","doi":"10.1109/SIMSYM.2002.1000140","DOIUrl":"https://doi.org/10.1109/SIMSYM.2002.1000140","url":null,"abstract":"CSIM18 simulation models are often built as Microsoft Windows console-mode programs. A tool named REMOTE was developed to enable automatic, remote execution of CSIM18 models (and of other console mode programs) in a Windows environment. A master PC distributes the programs to remote PCs and collects the output files as the remote model executions complete. The status of remotely executing models can be viewed at the master. The REMOTE tool utilizes idle non-dedicated PC CPU cycles during nights and weekends to speed-up the model execution phase of a large modeling project. The REMOTE executable can be distributed via email attachment and does not need any special installation or configuration. REMOTE is currently being used in an ongoing investigation of new variable-length packet switch architectures. REMOTE is freely available from the author.","PeriodicalId":198576,"journal":{"name":"Proceedings 35th Annual Simulation Symposium. SS 2002","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114800576","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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