This paper describes the general system and software architecture for the Internet-based robotic teleoperation system using virtual reality tools. The existing technology and application are discussed in this paper. An example is also presented based on the general architecture. Finally, the conclusion and future research direction are given.
{"title":"Virtual Reality Tools for Internet-Based Robotic Teleoperation","authors":"Xiaoli Yang, Qing Chen","doi":"10.1109/DS-RT.2004.41","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.41","url":null,"abstract":"This paper describes the general system and software architecture for the Internet-based robotic teleoperation system using virtual reality tools. The existing technology and application are discussed in this paper. An example is also presented based on the general architecture. Finally, the conclusion and future research direction are given.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114848724","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}
D. Kranzlmüller, H. Rosmanith, P. Heinzlreiter, Martin Polak
The grid has received a substantial amount of interest (and funding) over the past few years, even though the majority of grid applications are still batch-oriented. For this reason, extensions to grid middleware are a basic necessity to advance the idea of the grid into new application domains. The glogin tool and its integration into the Grid Visualization Kernel (GVK) yield both, interactivity and visualization, into the grid. While glogin enables the tunneling of arbitrary interactive traffic in and out of the grid, GVK offers transparent visualization services for grid applications while exploiting the grid’s performance for time-consuming visualization tasks. In this paper, the utilization of glogin and GVK is demonstrated for Virtual Reality (VR) environments. Two distinct approaches for VR, using either abstract visualization objects or video streams, are explained, highlighting advantages and disadvantages of each.
{"title":"Interactive Virtual Reality on the Grid","authors":"D. Kranzlmüller, H. Rosmanith, P. Heinzlreiter, Martin Polak","doi":"10.1109/DS-RT.2004.25","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.25","url":null,"abstract":"The grid has received a substantial amount of interest (and funding) over the past few years, even though the majority of grid applications are still batch-oriented. For this reason, extensions to grid middleware are a basic necessity to advance the idea of the grid into new application domains. The glogin tool and its integration into the Grid Visualization Kernel (GVK) yield both, interactivity and visualization, into the grid. While glogin enables the tunneling of arbitrary interactive traffic in and out of the grid, GVK offers transparent visualization services for grid applications while exploiting the grid’s performance for time-consuming visualization tasks. In this paper, the utilization of glogin and GVK is demonstrated for Virtual Reality (VR) environments. Two distinct approaches for VR, using either abstract visualization objects or video streams, are explained, highlighting advantages and disadvantages of each.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133263255","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 hybrid strategy-based modeling approach is a method for reducing the number of network packets that need to be transmitted to maintain global consistency in Distributed Interactive Applications. It combines a short-term model such as dead reckoning with a long-term strategy model. A key aspect of this approach is to determine strategies that users adopt in navigating the simulated environment to satisfy some objective or goal. Computer-generated artificial entities called BOTS, navigate by employing an Artificial Intelligence technique called path finding. This paper proposes using the A* path finding algorithm to automatically compute strategies that human users might take through the simulated environment. Since the A* algorithm operates on a graph representation of the environment and because of the real-time constraints imposed on Distributed Interactive Applications, the paper also carries out a comparative analysis of two extreme graph representations of the environment — a standard regular grid and a minimal grid representation. The comparison shows that the minimal grid leads to an order of magnitude reduction in real-time computation compared to the regular grid. In addition the paths computed using the minimal grid and the A* algorithm are used to determine strategy models as part of the hybrid strategy-based modeling approach. It is shown that this reduces the network traffic required to maintain global consistency of entity dynamics in two simulated environments.
{"title":"Visibility Path-Finding in Relation to Hybrid Strategy-Based Models in Distributed Interactive Applications","authors":"D. Madden, D. Delaney, S. McLoone, Tomas E. Ward","doi":"10.1109/DS-RT.2004.42","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.42","url":null,"abstract":"The hybrid strategy-based modeling approach is a method for reducing the number of network packets that need to be transmitted to maintain global consistency in Distributed Interactive Applications. It combines a short-term model such as dead reckoning with a long-term strategy model. A key aspect of this approach is to determine strategies that users adopt in navigating the simulated environment to satisfy some objective or goal. Computer-generated artificial entities called BOTS, navigate by employing an Artificial Intelligence technique called path finding. This paper proposes using the A* path finding algorithm to automatically compute strategies that human users might take through the simulated environment. Since the A* algorithm operates on a graph representation of the environment and because of the real-time constraints imposed on Distributed Interactive Applications, the paper also carries out a comparative analysis of two extreme graph representations of the environment — a standard regular grid and a minimal grid representation. The comparison shows that the minimal grid leads to an order of magnitude reduction in real-time computation compared to the regular grid. In addition the paths computed using the minimal grid and the A* algorithm are used to determine strategy models as part of the hybrid strategy-based modeling approach. It is shown that this reduces the network traffic required to maintain global consistency of entity dynamics in two simulated environments.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127102665","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}
3D virtual simulation environments (VE) applications have been impelled mainly by the computer games industry, military and industrial training and product design development. However, most of the existing systems are focused on specific tasks and have a supporting structure, which is closely tight to the application. As a consequence, a change in the application usually means a change in the supporting structure too, making it difficult and expensive to develop new or to extend existing VEs. In this paper, we present a novel approach to building and extending 3D virtual simulation environments through the integration of interactive non-linear stories and Virtual Reality. With this approach, VEs are composed as non-linear stories which can be changed either completely or partly, making it easier for developers to build and/or extend VEs applications, such as highly dynamic marketing campaigns to 3D virtual shops, customized training courses, educational and entertainment games, etc. Moreover, the use of a non-linear story for building a VE application can also facilitate the communication among the different professionals involved in the building of complex VE applications.
{"title":"3D Web-Based Virtual Simulation Environments Extensibility through Interactive Non-Linear Stories","authors":"A. Boukerche, R. B. Araujo, Diego Daniel Duarte","doi":"10.1109/DS-RT.2004.1","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.1","url":null,"abstract":"3D virtual simulation environments (VE) applications have been impelled mainly by the computer games industry, military and industrial training and product design development. However, most of the existing systems are focused on specific tasks and have a supporting structure, which is closely tight to the application. As a consequence, a change in the application usually means a change in the supporting structure too, making it difficult and expensive to develop new or to extend existing VEs. In this paper, we present a novel approach to building and extending 3D virtual simulation environments through the integration of interactive non-linear stories and Virtual Reality. With this approach, VEs are composed as non-linear stories which can be changed either completely or partly, making it easier for developers to build and/or extend VEs applications, such as highly dynamic marketing campaigns to 3D virtual shops, customized training courses, educational and entertainment games, etc. Moreover, the use of a non-linear story for building a VE application can also facilitate the communication among the different professionals involved in the building of complex VE applications.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127959456","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}
Aaron McCoy, S. McLoone, Tomas E. Ward, D. Delaney
Distributed Interactive Applications (DIAs) have been gaining commercial success in recent years due to the widespread appeal of networked multiplayer computer games. Within these games, participants interact with each other and their environment, producing complex behavioural patterns that evolve over time. These patterns are non-linear, and often appear to exhibit dependencies under certain conditions. In this paper, we analyse the behavioural patterns of two users interacting in a DIA. Our motivation behind this analysis is to construct models of user behaviour that can be used within Entity-State-Update (ESU) mechanisms. By representing their behaviour as time-series datasets, we investigate the use of simple statistical dependence measures to help partition the datasets and identify three different types of behavioural states exhibited by the two users. It is our intention that future research on ESU mechanisms can utilize this behavioural partitioning to reduce the network traffic in a DIA based on a hybrid-model approach.
{"title":"Investigating Behavioural State Data-Partitioning for User-Modelling in Distributed Interactive Applications","authors":"Aaron McCoy, S. McLoone, Tomas E. Ward, D. Delaney","doi":"10.1109/DS-RT.2004.26","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.26","url":null,"abstract":"Distributed Interactive Applications (DIAs) have been gaining commercial success in recent years due to the widespread appeal of networked multiplayer computer games. Within these games, participants interact with each other and their environment, producing complex behavioural patterns that evolve over time. These patterns are non-linear, and often appear to exhibit dependencies under certain conditions. In this paper, we analyse the behavioural patterns of two users interacting in a DIA. Our motivation behind this analysis is to construct models of user behaviour that can be used within Entity-State-Update (ESU) mechanisms. By representing their behaviour as time-series datasets, we investigate the use of simple statistical dependence measures to help partition the datasets and identify three different types of behavioural states exhibited by the two users. It is our intention that future research on ESU mechanisms can utilize this behavioural partitioning to reduce the network traffic in a DIA based on a hybrid-model approach.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129481842","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}
D. Marshall, D. Delaney, S. McLoone, Tomas E. Ward
As Distributed Interactive Applications (DIAs) become increasingly more prominent in the video game industry they must scale to accommodate progressively more users and maintain a globally consistent worldview. However, network constraints, such as bandwidth, limit the amount of communication allowed between users. Several methods of reducing network communication packets, while maintaining consistency, exist. These include dead reckoning and the hybrid strategy-based modelling approach. This latter method combines a short-term model such as dead reckoning with a long-term strategy model of user behaviour. By employing the strategy that most closely represents user behaviour, a reduction in the number of network packets that must be transmitted to maintain consistency has been shown. In this paper a novel method for constructing multiple long-term strategies using dead reckoning and polygons is described. Furthermore the algorithms are implemented in an industry-proven game engine known as Torque. A series of experiments are executed to investigate the effects of varying the spatial density of strategy models on the number of packets that need to be transmitted to maintain the global consistency of the DIA. The results show that increasing the spatial density of strategy models allows a higher consistency to be achieved with fewer packets using the hybrid strategy-based model than with pure dead reckoning. In some cases, the hybrid strategy-based model completely replaces dead reckoning as a means of communicating updates.
{"title":"Exploring the Spatial Density of Strategy Models in a Realistic Distributed Interactive Application","authors":"D. Marshall, D. Delaney, S. McLoone, Tomas E. Ward","doi":"10.1109/DS-RT.2004.20","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.20","url":null,"abstract":"As Distributed Interactive Applications (DIAs) become increasingly more prominent in the video game industry they must scale to accommodate progressively more users and maintain a globally consistent worldview. However, network constraints, such as bandwidth, limit the amount of communication allowed between users. Several methods of reducing network communication packets, while maintaining consistency, exist. These include dead reckoning and the hybrid strategy-based modelling approach. This latter method combines a short-term model such as dead reckoning with a long-term strategy model of user behaviour. By employing the strategy that most closely represents user behaviour, a reduction in the number of network packets that must be transmitted to maintain consistency has been shown. In this paper a novel method for constructing multiple long-term strategies using dead reckoning and polygons is described. Furthermore the algorithms are implemented in an industry-proven game engine known as Torque. A series of experiments are executed to investigate the effects of varying the spatial density of strategy models on the number of packets that need to be transmitted to maintain the global consistency of the DIA. The results show that increasing the spatial density of strategy models allows a higher consistency to be achieved with fewer packets using the hybrid strategy-based model than with pure dead reckoning. In some cases, the hybrid strategy-based model completely replaces dead reckoning as a means of communicating updates.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122703514","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}
Although web-based 3D virtual simulation environments are appealing applications, their construction in large scale is a challenging task. Existing systems that support 3D virtual environments focus typically on specific tasks and have a supporting structure, which is closely tight to the application. As a consequence, a change in the application usually means a change in the supporting structure too, making it difficult and expensive to develop new or to extend/change existing VE applications. Thus, solutions that can decrease the development time of 3D virtual environments are most welcome. This paper introduces a novel approach for building and extending virtual environments. An XML-based mark up language, VEML, is presented, which describes simulations through the concept of atomic simulation. VEML can be used to create and/or to extend highly dynamic 3D virtual environments, such as marketing campaigns for virtual shopping mall, customized training environments, etc.
{"title":"VEML: A Mark Up Language to Describe Web-Based Virtual Environment through Atomic Simulations","authors":"A. Boukerche, Diego Daniel Duarte, R. B. Araujo","doi":"10.1109/DS-RT.2004.40","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.40","url":null,"abstract":"Although web-based 3D virtual simulation environments are appealing applications, their construction in large scale is a challenging task. Existing systems that support 3D virtual environments focus typically on specific tasks and have a supporting structure, which is closely tight to the application. As a consequence, a change in the application usually means a change in the supporting structure too, making it difficult and expensive to develop new or to extend/change existing VE applications. Thus, solutions that can decrease the development time of 3D virtual environments are most welcome. This paper introduces a novel approach for building and extending virtual environments. An XML-based mark up language, VEML, is presented, which describes simulations through the concept of atomic simulation. VEML can be used to create and/or to extend highly dynamic 3D virtual environments, such as marketing campaigns for virtual shopping mall, customized training environments, etc.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124060619","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}
Mohamed Abdur Rahman, M. A. Hossain, Abdulmotaleb El Saddik
Navigation in 3D world has reached its pinnacle with the advent of several technologies like JAVA, XML, WEB SERVICES, VRML, X3D etc. A lot of efforts have been given to visualize and navigate in virtual mall, cities, digital libraries etc. Most of them visualize only static objects. We designed a Virtual Reality (VR) Tool, called Learning Object Repository Navigation and Authoring in Virtual environment (LORNAV) that extracts Learning Object Metadata (LOM) dynamically from repositories and creates 3D representation of these objects. The proposed tool provides several facilities such as personalized navigation allowing a user to view content that is of interest to him. It also helps users to create new aggregated Learning Objects (LOs) from existing ones in a 3D Environment to be presented in SMIL format.
{"title":"LORNAV: A Demo of a Virtual Reality Tool for Navigation and Authoring of Learning Object Repositories","authors":"Mohamed Abdur Rahman, M. A. Hossain, Abdulmotaleb El Saddik","doi":"10.1109/DS-RT.2004.28","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.28","url":null,"abstract":"Navigation in 3D world has reached its pinnacle with the advent of several technologies like JAVA, XML, WEB SERVICES, VRML, X3D etc. A lot of efforts have been given to visualize and navigate in virtual mall, cities, digital libraries etc. Most of them visualize only static objects. We designed a Virtual Reality (VR) Tool, called Learning Object Repository Navigation and Authoring in Virtual environment (LORNAV) that extracts Learning Object Metadata (LOM) dynamically from repositories and creates 3D representation of these objects. The proposed tool provides several facilities such as personalized navigation allowing a user to view content that is of interest to him. It also helps users to create new aggregated Learning Objects (LOs) from existing ones in a 3D Environment to be presented in SMIL format.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127766936","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 development of simulators for complex systems like nuclear power plants is a hard task where many different factors have to be considered. This paper presents a simulation environment composed by a simulation kernel and supported by a set of tools and simulation models that allow the real-time simulation of the control room of nuclear power plants. The developed simulators allow the training of the operators for the operations and maintenance of the power plant in a safe way and they are being used in full scope simulations for different real power plants. In this type of systems, where many components have to interoperate between them, the communications play a main role. The main contribution of the paper is to show the lessons learned from the utilization of CORBA and Real-time CORBA in the development of this type of simulators.
{"title":"A Simulation Environment for Nuclear Power Plants","authors":"M. Díaz, Daniel Garrido","doi":"10.1109/DS-RT.2004.5","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.5","url":null,"abstract":"The development of simulators for complex systems like nuclear power plants is a hard task where many different factors have to be considered. This paper presents a simulation environment composed by a simulation kernel and supported by a set of tools and simulation models that allow the real-time simulation of the control room of nuclear power plants. The developed simulators allow the training of the operators for the operations and maintenance of the power plant in a safe way and they are being used in full scope simulations for different real power plants. In this type of systems, where many components have to interoperate between them, the communications play a main role. The main contribution of the paper is to show the lessons learned from the utilization of CORBA and Real-time CORBA in the development of this type of simulators.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132189754","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}
Many teamwork tasks in the real world require the shared manipulation of objects, both sequentially and concurrently. Collaborative virtual environments (CVE) bring remote people together in an interactive, spatial social and information context that is distributed over a network. Supporting highly collaborative tasks in a natural manner requires a thourough understanding of event traffic as distinct forms of shared object manipulation are bound to diverse real-time and consistency constraints. This position paper summarises our findings during user trials around the shared manipulation of objects within linked immersive displays and introduce a CVE system with a flexible event-handling framework that allows task-oriented concictency control.
{"title":"Collaboration around Shared Objects in Immersive Virtual Environments","authors":"R. Wolff, D. Roberts, Oliver Otto","doi":"10.1109/DS-RT.2004.11","DOIUrl":"https://doi.org/10.1109/DS-RT.2004.11","url":null,"abstract":"Many teamwork tasks in the real world require the shared manipulation of objects, both sequentially and concurrently. Collaborative virtual environments (CVE) bring remote people together in an interactive, spatial social and information context that is distributed over a network. Supporting highly collaborative tasks in a natural manner requires a thourough understanding of event traffic as distinct forms of shared object manipulation are bound to diverse real-time and consistency constraints. This position paper summarises our findings during user trials around the shared manipulation of objects within linked immersive displays and introduce a CVE system with a flexible event-handling framework that allows task-oriented concictency control.","PeriodicalId":355772,"journal":{"name":"Eighth IEEE International Symposium on Distributed Simulation and Real-Time Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131032423","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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