Pub Date : 2002-12-11DOI: 10.1109/MMSE.2002.1181617
S. Tu, Liang Xu, Ying Wu
In a virtual training classroom that supports classroom interactions with real-time audio and video (A/V), we adopted the peer-to-peer model for A/V streaming. Using the Jini network technology, we integrated the peer-to-peer subsystem into the client-server centric Web-based training systems. Not only does the lookup service of the Jini network provide a mechanism for objects to discover remote services, Jini also provides the proxy and remote events, two patterns to accomplish remote control. When an object needs to control many activities associated with a remote object, the proxy pattern is more appropriate. By holding a proxy of the remote object, the controlling object can freely invoke any remote function. On the other hand, if an object needs to react to one event associated with each of the related objects, the remote event mechanism is a handier means. We also implemented an application-level simplified multipoint A/V streaming, which is useful for the companies whose networks do not support multicast over the Internet.
{"title":"A framework approach to accommodation of multimedia communications for training systems","authors":"S. Tu, Liang Xu, Ying Wu","doi":"10.1109/MMSE.2002.1181617","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181617","url":null,"abstract":"In a virtual training classroom that supports classroom interactions with real-time audio and video (A/V), we adopted the peer-to-peer model for A/V streaming. Using the Jini network technology, we integrated the peer-to-peer subsystem into the client-server centric Web-based training systems. Not only does the lookup service of the Jini network provide a mechanism for objects to discover remote services, Jini also provides the proxy and remote events, two patterns to accomplish remote control. When an object needs to control many activities associated with a remote object, the proxy pattern is more appropriate. By holding a proxy of the remote object, the controlling object can freely invoke any remote function. On the other hand, if an object needs to react to one event associated with each of the related objects, the remote event mechanism is a handier means. We also implemented an application-level simplified multipoint A/V streaming, which is useful for the companies whose networks do not support multicast over the Internet.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130975192","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}
Large real-time multimedia systems such as flight simulators have adopted multiprocessor architecture to handle the large amount of events and computations. Existing realtime scheduling algorithms designed for single-processor systems such as Rate Monotonic (RM) and Earliest Deadline First Algorithm (EDF) have very poor performance on multiprocessor systems. On the other hand, most online scheduling algorithms for multiprocessor systems have poor schedulability conditions for real-time applications. In this paper, we study different ways to design real-time applications on SMP machines.
飞行模拟器等大型实时多媒体系统采用多处理器架构来处理大量的事件和计算。现有的单处理器系统实时调度算法，如速率单调算法(Rate Monotonic, RM)和最早截止时间优先算法(early Deadline First Algorithm, EDF)在多处理器系统上的性能很差。另一方面，大多数多处理器系统的在线调度算法在实时应用中具有较差的可调度性条件。在本文中，我们研究了在SMP机器上设计实时应用的不同方法。
{"title":"Designing multimedia applications on real-time systems with SMP architecture","authors":"Kwei-Jay Lin, Yu-Chung Wang, Ting-Hua Chien, Yaa-Jyun Yeh","doi":"10.1109/MMSE.2002.1181591","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181591","url":null,"abstract":"Large real-time multimedia systems such as flight simulators have adopted multiprocessor architecture to handle the large amount of events and computations. Existing realtime scheduling algorithms designed for single-processor systems such as Rate Monotonic (RM) and Earliest Deadline First Algorithm (EDF) have very poor performance on multiprocessor systems. On the other hand, most online scheduling algorithms for multiprocessor systems have poor schedulability conditions for real-time applications. In this paper, we study different ways to design real-time applications on SMP machines.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114069267","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 : 2002-12-11DOI: 10.1109/MMSE.2002.1181618
P. Sumari, A. Samsudin, H. Kamarulhaili
Video on demand (VOD) is a system that provides a service to users to browse and watch videos within a computer network. One of the most challenging aspects in such system is to have a VOD server with a capability of retrieving and transmitting different blocks of videos simultaneously. A part from this the VOD server should also capable of producing high number of simultaneous streams with a low average waiting time. In this paper we present a new data storage scheme employed by the VOD server to eliminate latency and hence producing maximum number of simultaneous streams. In this scheme the disk is divided into regions and blocks of video are scattered within the regions based on the residual theory rule. We also developed a stream caching technique for reducing the average waiting time of the system.
{"title":"Data storage and retrieval for video-on-demand servers","authors":"P. Sumari, A. Samsudin, H. Kamarulhaili","doi":"10.1109/MMSE.2002.1181618","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181618","url":null,"abstract":"Video on demand (VOD) is a system that provides a service to users to browse and watch videos within a computer network. One of the most challenging aspects in such system is to have a VOD server with a capability of retrieving and transmitting different blocks of videos simultaneously. A part from this the VOD server should also capable of producing high number of simultaneous streams with a low average waiting time. In this paper we present a new data storage scheme employed by the VOD server to eliminate latency and hence producing maximum number of simultaneous streams. In this scheme the disk is divided into regions and blocks of video are scattered within the regions based on the residual theory rule. We also developed a stream caching technique for reducing the average waiting time of the system.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114561713","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 : 2002-12-11DOI: 10.1109/MMSE.2002.1181599
Jiangshan Xu, Liang-Jie Zhang, Haiming Lu, Yanda Li
Aspects of personalized TV program recommendation systems are reviewed. An introduction and relevant work are presented, and philosophies of program description, user profiling and the matching mechanism are illustrated, especially for strategies such as implicit and explicit feedback, and content-based and collaborative filtering techniques. A new system quality evaluation method is then presented. In addition, we propose a next generation conceptual architecture for integrating a real-time program rating mechanism with a personalization system using Web services.
{"title":"The development and prospect of personalized TV program recommendation systems","authors":"Jiangshan Xu, Liang-Jie Zhang, Haiming Lu, Yanda Li","doi":"10.1109/MMSE.2002.1181599","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181599","url":null,"abstract":"Aspects of personalized TV program recommendation systems are reviewed. An introduction and relevant work are presented, and philosophies of program description, user profiling and the matching mechanism are illustrated, especially for strategies such as implicit and explicit feedback, and content-based and collaborative filtering techniques. A new system quality evaluation method is then presented. In addition, we propose a next generation conceptual architecture for integrating a real-time program rating mechanism with a personalization system using Web services.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121501405","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 : 2002-12-11DOI: 10.1109/MMSE.2002.1181595
Alexander Davis, Du Zhang
The simple object access protocol (SOAP) is a recent technology, which is aimed at replacing traditional methods of remote communications, such as the RPC-based Distributed Component Object Model (DCOM). Designed with the goal of increasing interoperability among a wide range of programs and environments, SOAP allows applications written in different languages and deployed on different platforms to communicate with each other over the network. While SOAP offers obvious benefits in the world of interoperability, it comes at the price of performance degradation and additional development efforts required for implementation of features missing from SOAP, such as security and state management. This paper reports the outcome of a comparative study of SOAP and DCOM in terms of features, development effort, and application performance. The results indicate that SOAP performance on a homogeneous platform is consistently worse than that of DCOM. Depending on the operation and amount of data transferred, SOAP performance degradation can range from minor (e.g. two or three times slower than DCOM) to major (e.g. twenty or more times slower). Based on lines of code statistics, SOAP application development effort should be slightly (/spl sim/10%) higher. If an application has to rely on the features such as state management or security, which are missing from SOAP, then SOAP implementation will require substantial design efforts and, in certain cases, may not be feasible at all. We recommend application developers to consider these issues when preparing to move their applications to SOAP.
{"title":"A comparative study of DCOM and SOAP","authors":"Alexander Davis, Du Zhang","doi":"10.1109/MMSE.2002.1181595","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181595","url":null,"abstract":"The simple object access protocol (SOAP) is a recent technology, which is aimed at replacing traditional methods of remote communications, such as the RPC-based Distributed Component Object Model (DCOM). Designed with the goal of increasing interoperability among a wide range of programs and environments, SOAP allows applications written in different languages and deployed on different platforms to communicate with each other over the network. While SOAP offers obvious benefits in the world of interoperability, it comes at the price of performance degradation and additional development efforts required for implementation of features missing from SOAP, such as security and state management. This paper reports the outcome of a comparative study of SOAP and DCOM in terms of features, development effort, and application performance. The results indicate that SOAP performance on a homogeneous platform is consistently worse than that of DCOM. Depending on the operation and amount of data transferred, SOAP performance degradation can range from minor (e.g. two or three times slower than DCOM) to major (e.g. twenty or more times slower). Based on lines of code statistics, SOAP application development effort should be slightly (/spl sim/10%) higher. If an application has to rely on the features such as state management or security, which are missing from SOAP, then SOAP implementation will require substantial design efforts and, in certain cases, may not be feasible at all. We recommend application developers to consider these issues when preparing to move their applications to SOAP.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115886633","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 : 2002-12-11DOI: 10.1109/MMSE.2002.1181620
M. Cortes, J. Ensor
Narnia is a middleware that helps programmers build multimedia communication services. This middleware uses a collection of familiar programming abstractions - including events, event handlers, resources, sessions, and user roles - to provide both a service development environment and a service execution environment. The run-time environment, the Narnia virtual machine, provides means for creating, transmitting, and consuming events as well as means for creating, loading, and executing sessions and event handlers. The Narnia middleware has served as the development and execution platform for a few applications, including an audio/video chat application and a SIP proxy simulator. The paper reports on how well these applications handle various user request workloads. These early system performance measurements indicate the effectiveness of Narnia in supporting development and deployment of scalable network multimedia services.
{"title":"Narnia: a virtual machine for multimedia communication services","authors":"M. Cortes, J. Ensor","doi":"10.1109/MMSE.2002.1181620","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181620","url":null,"abstract":"Narnia is a middleware that helps programmers build multimedia communication services. This middleware uses a collection of familiar programming abstractions - including events, event handlers, resources, sessions, and user roles - to provide both a service development environment and a service execution environment. The run-time environment, the Narnia virtual machine, provides means for creating, transmitting, and consuming events as well as means for creating, loading, and executing sessions and event handlers. The Narnia middleware has served as the development and execution platform for a few applications, including an audio/video chat application and a SIP proxy simulator. The paper reports on how well these applications handle various user request workloads. These early system performance measurements indicate the effectiveness of Narnia in supporting development and deployment of scalable network multimedia services.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116262450","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 : 2002-12-11DOI: 10.1109/MMSE.2002.1181632
Andreas Hartl, Erwin Aitenbichler, Gerhard Austaller, A. Heinemann, Tobias Limberger, E. Braun, M. Mühlhäuser
Ubiquitous computing focusing on users and tasks instead of devices and singular applications is an attractive vision for the future. The idea of nomadic, mobile users in particular poses new challenges for hardware and software. Mobile devices provide vastly different presentation capabilities and need to integrate into heterogeneous environments. Network bandwidth is far from being constant and services may be available only when online. This paper presents MUNDO, an infrastructure for ubiquitous computing that addresses these challenges. The infrastructure is intended to be non-monolithic with its parts supporting mobile computing using multi-modal user interfaces, mobile data delivery, and ad-hoc communication and networking.
{"title":"Engineering multimedia-aware personalized ubiquitous services","authors":"Andreas Hartl, Erwin Aitenbichler, Gerhard Austaller, A. Heinemann, Tobias Limberger, E. Braun, M. Mühlhäuser","doi":"10.1109/MMSE.2002.1181632","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181632","url":null,"abstract":"Ubiquitous computing focusing on users and tasks instead of devices and singular applications is an attractive vision for the future. The idea of nomadic, mobile users in particular poses new challenges for hardware and software. Mobile devices provide vastly different presentation capabilities and need to integrate into heterogeneous environments. Network bandwidth is far from being constant and services may be available only when online. This paper presents MUNDO, an infrastructure for ubiquitous computing that addresses these challenges. The infrastructure is intended to be non-monolithic with its parts supporting mobile computing using multi-modal user interfaces, mobile data delivery, and ad-hoc communication and networking.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114145591","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 : 2002-12-11DOI: 10.1109/MMSE.2002.1181615
Chiung-Hon Leon Lee, Alan Liu
An agent-based system is a complex software system with functional and nonfunctional constrain. Designing and building such system is a complex task. This article presents a goal-driven use case based method for agent-based system requirements analysis. The use case approach is used to elicit system requirements from user's point of view. Related use cases are assigned to corresponding roles. Each use case is then extended with goals for implicit requirements analysis from a role's point of view. Each role is treated as an internal actor to find more system specific use cases. Five relationships between use cases and goals are then identified: satisfied, satisfiable, denied, deniable, and independent. Those relationships help find the relationship among roles. Such relationships can be classified as cooperative, conflict, counterbalanced, and irrelevant. Identifying those relationships assists the system analyzer to analyze and optimized the relationships among roles. The contribution of this article is a proposal to a systematic approach for implicit requirements analysis for agent-based systems.
{"title":"A method for agent-based system requirements analysis","authors":"Chiung-Hon Leon Lee, Alan Liu","doi":"10.1109/MMSE.2002.1181615","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181615","url":null,"abstract":"An agent-based system is a complex software system with functional and nonfunctional constrain. Designing and building such system is a complex task. This article presents a goal-driven use case based method for agent-based system requirements analysis. The use case approach is used to elicit system requirements from user's point of view. Related use cases are assigned to corresponding roles. Each use case is then extended with goals for implicit requirements analysis from a role's point of view. Each role is treated as an internal actor to find more system specific use cases. Five relationships between use cases and goals are then identified: satisfied, satisfiable, denied, deniable, and independent. Those relationships help find the relationship among roles. Such relationships can be classified as cooperative, conflict, counterbalanced, and irrelevant. Identifying those relationships assists the system analyzer to analyze and optimized the relationships among roles. The contribution of this article is a proposal to a systematic approach for implicit requirements analysis for agent-based systems.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121634614","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 : 2002-12-11DOI: 10.1109/MMSE.2002.1181630
Shahab Baqai, F. A. Baqai, Usman Hameed, S. Sheikh, A. Khokhar
We investigate the effect of network errors on Embedded Zerotree Wavelet (EZW) encoded images and propose modifications to the EZW coder to increase error resilience in bursty packet loss conditions. A hybrid-encoding scheme that uses data interleaving to spread correlated information into independently processed groups and layered encoding to protect significant information within each group is presented. Simulation results for various packet loss percentages show the improved error resiliency of our scheme in random and bursty packet loss environments.
{"title":"Error resilience of EZW coder for image transmission in lossy networks","authors":"Shahab Baqai, F. A. Baqai, Usman Hameed, S. Sheikh, A. Khokhar","doi":"10.1109/MMSE.2002.1181630","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181630","url":null,"abstract":"We investigate the effect of network errors on Embedded Zerotree Wavelet (EZW) encoded images and propose modifications to the EZW coder to increase error resilience in bursty packet loss conditions. A hybrid-encoding scheme that uses data interleaving to spread correlated information into independently processed groups and layered encoding to protect significant information within each group is presented. Simulation results for various packet loss percentages show the improved error resiliency of our scheme in random and bursty packet loss environments.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127412568","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 : 2002-12-11DOI: 10.1109/MMSE.2002.1181612
Baowen Xu, Weifeng Zhang, Hongji Yang
Popular WWW pages are stored in places which are close to users by WWW cache technology to speed up the fetching of these objects. Information in the WWW cache shows users' recent interest. Users' interest can be widely used in customizing WWW pages, filtering information, pre-fetching information and so on. The key to using information in the WWW cache effectively is to build an adaptive user interest model and construct an adaptive algorithm for interest mining. Interest can be specialized by the tuple (term, weight) in the simple interest model. Association relations are not mined in this model, so the interest cannot be associated in expressing users' interest. Basing on analyzing the WWW cache model, we propose a two-dimension interest model. It is proved that mined users' interest can show users' current interest states. Inferential relations are well considered in the two-dimension interest model. This model is not a simple extension of the simple interest model, but the full update and the related algorithm. Interrelated methods for storing the two-dimension interest model, computing the model effectively and updating the model in real time are considered.
{"title":"Mining users' two-dimension interests from cache","authors":"Baowen Xu, Weifeng Zhang, Hongji Yang","doi":"10.1109/MMSE.2002.1181612","DOIUrl":"https://doi.org/10.1109/MMSE.2002.1181612","url":null,"abstract":"Popular WWW pages are stored in places which are close to users by WWW cache technology to speed up the fetching of these objects. Information in the WWW cache shows users' recent interest. Users' interest can be widely used in customizing WWW pages, filtering information, pre-fetching information and so on. The key to using information in the WWW cache effectively is to build an adaptive user interest model and construct an adaptive algorithm for interest mining. Interest can be specialized by the tuple (term, weight) in the simple interest model. Association relations are not mined in this model, so the interest cannot be associated in expressing users' interest. Basing on analyzing the WWW cache model, we propose a two-dimension interest model. It is proved that mined users' interest can show users' current interest states. Inferential relations are well considered in the two-dimension interest model. This model is not a simple extension of the simple interest model, but the full update and the related algorithm. Interrelated methods for storing the two-dimension interest model, computing the model effectively and updating the model in real time are considered.","PeriodicalId":201661,"journal":{"name":"Fourth International Symposium on Multimedia Software Engineering, 2002. Proceedings.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129152882","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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