Pub Date : 2005-07-11DOI: 10.1109/PERSER.2005.1506408
C. Mavromoustakis, H. Karatza
In the recent years, mobility is gaining popularity for non critical civilian applications. Hybrid and pervasive computing environments with billions of users, devices, and services, demand ensured end to end reliability and integrity. However due to the asymmetry in wireless communication and the scarceness of wireless resources, the use of such networks as a mean of file sharing is not always successful. This paper proposes an approach for reliable file sharing based on the advantages of epidemic selective dissemination through fixed and mobile infostations. The proposed scheme attempts to fill the gap between mobility and reliable file sharing for mobile peer to peer users. Facing the problem of flooding this method successfully enables end to end reliability by forwarding requested packets to epidemically 'selected' users in the network. Thorough examination is made for the performance and reliability of the epidemic selective caching method proving it's robustness in reliable file sharing among mobile peers.
{"title":"Reliable file sharing scheme for mobile peer-to-peer users using epidemic selective caching","authors":"C. Mavromoustakis, H. Karatza","doi":"10.1109/PERSER.2005.1506408","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506408","url":null,"abstract":"In the recent years, mobility is gaining popularity for non critical civilian applications. Hybrid and pervasive computing environments with billions of users, devices, and services, demand ensured end to end reliability and integrity. However due to the asymmetry in wireless communication and the scarceness of wireless resources, the use of such networks as a mean of file sharing is not always successful. This paper proposes an approach for reliable file sharing based on the advantages of epidemic selective dissemination through fixed and mobile infostations. The proposed scheme attempts to fill the gap between mobility and reliable file sharing for mobile peer to peer users. Facing the problem of flooding this method successfully enables end to end reliability by forwarding requested packets to epidemically 'selected' users in the network. Thorough examination is made for the performance and reliability of the epidemic selective caching method proving it's robustness in reliable file sharing among mobile peers.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115684826","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506564
A. Uyar, Wenjun Wu, Hasan Bulut, G. Fox
The availability of increasing network bandwidth and computing power provides new opportunities for videoconferencing systems over Internet. Multimedia capable devices with broadband Internet connections are spreading rapidly. Even cell phones will have broadband Internet access in the near future. This requires universally accessible and scalable videoconferencing systems that can deliver thousands of concurrent audio and video streams. However, developing videoconferencing systems over Internet is a challenging task, since audio and video communications require high bandwidth and low latency. In addition, the processing of audio and video streams is computing intensive. Therefore, it is particularly difficult to develop scalable systems that support high number of users with various capabilities. Current videoconferencing systems such as IP-Multicast and H.323 can not fully address the problem of scalability and universal accessibility. These systems lack flexible service oriented architecture to support increasingly diverse. We believe that with the advancements in computing power and network bandwidth, more flexible and service oriented systems should be developed. In this paper, we outline a service oriented architecture for videoconferencing, GlobalMMCS, based on a publish/subscribe event brokering network, NaradaBrokering.
{"title":"Service-oriented architecture for a scalable videoconferencing system","authors":"A. Uyar, Wenjun Wu, Hasan Bulut, G. Fox","doi":"10.1109/PERSER.2005.1506564","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506564","url":null,"abstract":"The availability of increasing network bandwidth and computing power provides new opportunities for videoconferencing systems over Internet. Multimedia capable devices with broadband Internet connections are spreading rapidly. Even cell phones will have broadband Internet access in the near future. This requires universally accessible and scalable videoconferencing systems that can deliver thousands of concurrent audio and video streams. However, developing videoconferencing systems over Internet is a challenging task, since audio and video communications require high bandwidth and low latency. In addition, the processing of audio and video streams is computing intensive. Therefore, it is particularly difficult to develop scalable systems that support high number of users with various capabilities. Current videoconferencing systems such as IP-Multicast and H.323 can not fully address the problem of scalability and universal accessibility. These systems lack flexible service oriented architecture to support increasingly diverse. We believe that with the advancements in computing power and network bandwidth, more flexible and service oriented systems should be developed. In this paper, we outline a service oriented architecture for videoconferencing, GlobalMMCS, based on a publish/subscribe event brokering network, NaradaBrokering.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116066811","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506388
Jun-Zhao Sun, Marko Jurmu, J. Riekki, J. Sauvola
The future communication trend in the Internet is rapidly moving towards mobile and pervasive computing. This emphasizes the network-dependency of terminals and applications, thus making a seamless and ubiquitous connectivity highly feasible. The mobility management of heterogeneous wireless resources is a key issue for this emerging paradigm. This paper presents the design and implementation of a middleware-based software architecture that enables terminals to adapt to fluctuations experienced in heterogeneous multi-access networks. This adaptation includes the dynamic selection of the most suitable connection for each application, as well as coping with a disconnection. Furthermore, it allows the applications to dynamically adapt their behavior according to the QoS-related changes in the underlying network interface. A test version was implemented based on the architecture. Experiments were conducted in a GPRS-WLAN test environment, from which the results were collected and analyzed.
{"title":"Virtual port-based channel level mobility management middleware in heterogeneous wireless networks","authors":"Jun-Zhao Sun, Marko Jurmu, J. Riekki, J. Sauvola","doi":"10.1109/PERSER.2005.1506388","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506388","url":null,"abstract":"The future communication trend in the Internet is rapidly moving towards mobile and pervasive computing. This emphasizes the network-dependency of terminals and applications, thus making a seamless and ubiquitous connectivity highly feasible. The mobility management of heterogeneous wireless resources is a key issue for this emerging paradigm. This paper presents the design and implementation of a middleware-based software architecture that enables terminals to adapt to fluctuations experienced in heterogeneous multi-access networks. This adaptation includes the dynamic selection of the most suitable connection for each application, as well as coping with a disconnection. Furthermore, it allows the applications to dynamically adapt their behavior according to the QoS-related changes in the underlying network interface. A test version was implemented based on the architecture. Experiments were conducted in a GPRS-WLAN test environment, from which the results were collected and analyzed.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117003164","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506393
A. Malatras, G. Pavlou, P. Belsis, S. Gritzalis, C. Skourlas, Ioannis Chalaris
Pervasive environments are mostly based on the ad hoc networking paradigm and are characterized by ubiquity in both users and devices and artefacts. In these inherently unstable conditions and bearing in mind the resources limitations that are attributed to participating devices, the deployment of knowledge management techniques is considered complicated due to the particular requirements. This paper addresses the issue of secure and distributed knowledge management applications in pervasive environments. We present a prototype implementation after having presented detailed design principles as far as the communications and the application itself is regarded. Robustness and lightweight implementation are the cornerstones of the proposed solution.
{"title":"Secure and distributed knowledge management in pervasive environments","authors":"A. Malatras, G. Pavlou, P. Belsis, S. Gritzalis, C. Skourlas, Ioannis Chalaris","doi":"10.1109/PERSER.2005.1506393","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506393","url":null,"abstract":"Pervasive environments are mostly based on the ad hoc networking paradigm and are characterized by ubiquity in both users and devices and artefacts. In these inherently unstable conditions and bearing in mind the resources limitations that are attributed to participating devices, the deployment of knowledge management techniques is considered complicated due to the particular requirements. This paper addresses the issue of secure and distributed knowledge management applications in pervasive environments. We present a prototype implementation after having presented detailed design principles as far as the communications and the application itself is regarded. Robustness and lightweight implementation are the cornerstones of the proposed solution.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129043360","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506410
Mijeom Kim, Mohan J. Kumar, B. Shirazi
We propose a service discovery architecture called VSD (service discovery based on volunteers) for heterogeneous and dynamic pervasive computing environments. The proposed architecture uses a small subset of the nodes called volunteers that perform directory services. Relatively stable and capable nodes serve as volunteers, thus recognizing node heterogeneity in terms of mobility and capability. We discuss characteristics of VSD architecture and methods to improve connectivity among volunteers for higher discovery rate. By showing that VSD performs quite well compared to a broadcast based scheme in MANET scenarios, we validate that VSD is a flexible and adaptable architecture appropriate for dynamic pervasive computing environments. VSD incorporates several novel features: i) handles dynamism and supports self-reconfiguration; ii) provides physical locality and scalability; and iii) improves reliability and copes with uncertainty through redundancy by forming overlapped clusters.
{"title":"Service discovery using volunteer nodes for pervasive environments","authors":"Mijeom Kim, Mohan J. Kumar, B. Shirazi","doi":"10.1109/PERSER.2005.1506410","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506410","url":null,"abstract":"We propose a service discovery architecture called VSD (service discovery based on volunteers) for heterogeneous and dynamic pervasive computing environments. The proposed architecture uses a small subset of the nodes called volunteers that perform directory services. Relatively stable and capable nodes serve as volunteers, thus recognizing node heterogeneity in terms of mobility and capability. We discuss characteristics of VSD architecture and methods to improve connectivity among volunteers for higher discovery rate. By showing that VSD performs quite well compared to a broadcast based scheme in MANET scenarios, we validate that VSD is a flexible and adaptable architecture appropriate for dynamic pervasive computing environments. VSD incorporates several novel features: i) handles dynamism and supports self-reconfiguration; ii) provides physical locality and scalability; and iii) improves reliability and copes with uncertainty through redundancy by forming overlapped clusters.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124109890","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506425
I. Satoh
This paper presents a self-organizing approach to developing and managing distributed software in pervasive computing environments. In such environments, people are surrounded by hundreds of mobile or embedded computers each of which may be used to support one or more user applications due to limitations in their individual computational capabilities. We need an approach to coordinating heterogeneous computers that acts as a virtual computer around a mobile and pervasive computing environment and supports various applications beyond the capabilities of single computers. This paper presents a framework for building and aggregating distributed applications from one or more mobile components that can be dynamically deployed at mobile or stationary computers during the execution of the application. Since the approach involves mobile-transparent communications between components and component relocation semantics, it enables a federation of components to adapt its structure and be deployed on multiple computers whose computational resources, such as input and output devices, can satisfy the requirement of the components in a self-organized manner. This paper also describes a prototype implementation of the approach and its application.
{"title":"Dynamic deployment of pervasive services","authors":"I. Satoh","doi":"10.1109/PERSER.2005.1506425","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506425","url":null,"abstract":"This paper presents a self-organizing approach to developing and managing distributed software in pervasive computing environments. In such environments, people are surrounded by hundreds of mobile or embedded computers each of which may be used to support one or more user applications due to limitations in their individual computational capabilities. We need an approach to coordinating heterogeneous computers that acts as a virtual computer around a mobile and pervasive computing environment and supports various applications beyond the capabilities of single computers. This paper presents a framework for building and aggregating distributed applications from one or more mobile components that can be dynamically deployed at mobile or stationary computers during the execution of the application. Since the approach involves mobile-transparent communications between components and component relocation semantics, it enables a federation of components to adapt its structure and be deployed on multiple computers whose computational resources, such as input and output devices, can satisfy the requirement of the components in a self-organized manner. This paper also describes a prototype implementation of the approach and its application.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131029261","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506566
L. Capra, S. Zachariadis, C. Mascolo
This paper presents Q-CAD, a resource discovery framework that enables pervasive computing applications to discover and select the resource(s) best satisfying the user needs, taking the current execution context and quality-of-service (QoS) requirements into account. The available resources are first screened, so that only those suitable to the current execution context of the application would be considered; the shortlisted resources are then evaluated against the QoS needs of the application, and a binding is established to the best available.
{"title":"Q-CAD: QoS and context aware discovery framework for mobile systems","authors":"L. Capra, S. Zachariadis, C. Mascolo","doi":"10.1109/PERSER.2005.1506566","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506566","url":null,"abstract":"This paper presents Q-CAD, a resource discovery framework that enables pervasive computing applications to discover and select the resource(s) best satisfying the user needs, taking the current execution context and quality-of-service (QoS) requirements into account. The available resources are first screened, so that only those suitable to the current execution context of the application would be considered; the shortlisted resources are then evaluated against the QoS needs of the application, and a binding is established to the best available.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132818887","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506409
J. Faizan, H. El-Rewini, M. Khalil
The current specification of Mobile IPv6 does not provide load balancing among multiple home agents on the home link. In this paper, we introduce a load balancing mechanism as an extension to Mobile IPv6 that provides an efficient dynamic load balancing among multiple home agents. It takes into account acceptable packet forwarding rate for each home agent, with the aim of reducing and preventing traffic bottlenecks at the home agent. The advantages of our load balancing mechanism over other protocols are transparent load balancing, reduced message overhead over the air interface, fair load distribution among the home agents, no service interruption in the upper layer applications during load balancing, efficient resource utilization, and increased overall system performance.
{"title":"Efficient dynamic load balancing for multiple home agents in Mobile IPv6 based networks","authors":"J. Faizan, H. El-Rewini, M. Khalil","doi":"10.1109/PERSER.2005.1506409","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506409","url":null,"abstract":"The current specification of Mobile IPv6 does not provide load balancing among multiple home agents on the home link. In this paper, we introduce a load balancing mechanism as an extension to Mobile IPv6 that provides an efficient dynamic load balancing among multiple home agents. It takes into account acceptable packet forwarding rate for each home agent, with the aim of reducing and preventing traffic bottlenecks at the home agent. The advantages of our load balancing mechanism over other protocols are transparent load balancing, reduced message overhead over the air interface, fair load distribution among the home agents, no service interruption in the upper layer applications during load balancing, efficient resource utilization, and increased overall system performance.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126582181","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506561
H. Tran, P. Watters, M. Hitchens, V. Varadharajan
Grids are popular mechanisms for resource exchange, but their pervasive, decentralized and loosely coupled characteristics make protecting services and resources difficult. In this paper, we propose a trust model for grid environments based on our novel recommendation method, a fair-trading scheme, and an access control model. This approach preserves the grid's decentralized structure and participant's autonomy, but also enables secure service exchange.
{"title":"Trust and authorization in the grid: a recommendation model","authors":"H. Tran, P. Watters, M. Hitchens, V. Varadharajan","doi":"10.1109/PERSER.2005.1506561","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506561","url":null,"abstract":"Grids are popular mechanisms for resource exchange, but their pervasive, decentralized and loosely coupled characteristics make protecting services and resources difficult. In this paper, we propose a trust model for grid environments based on our novel recommendation method, a fair-trading scheme, and an access control model. This approach preserves the grid's decentralized structure and participant's autonomy, but also enables secure service exchange.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114701602","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506386
Aditya Mohan, W. Hong, David E. Gay, P. Buonadonna, A. Mainwaring
This paper brings out the current state of art in multi-hop routing techniques for sensor networks, specifically for many-to-one periodic data collection. We evaluate the routing layers on a large scale Sensornet testbed of 100 nodes where the nodes are densely spaced. The evaluation was focused on trying to short list the routing layer with the best data reliability. Such an evaluation is expected to be useful to researchers building pervasive applications using TinyOS based sensors (micaa2 and mica2dot) and a multi-hop routing stack. We saw that the reliable time sync and the DSDV implementation in HSN (heterogeneous sensor network) routing stack performed the best, with percentage of successful transmissions averaging at 58.3% and 62.9% respectively. The nodes that were closer to the base station had a high success rate of 86.9% for HSN DSDV and 83% for reliable time sync.
{"title":"End-to-end performance characterization of Sensornet multi-hop routing","authors":"Aditya Mohan, W. Hong, David E. Gay, P. Buonadonna, A. Mainwaring","doi":"10.1109/PERSER.2005.1506386","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506386","url":null,"abstract":"This paper brings out the current state of art in multi-hop routing techniques for sensor networks, specifically for many-to-one periodic data collection. We evaluate the routing layers on a large scale Sensornet testbed of 100 nodes where the nodes are densely spaced. The evaluation was focused on trying to short list the routing layer with the best data reliability. Such an evaluation is expected to be useful to researchers building pervasive applications using TinyOS based sensors (micaa2 and mica2dot) and a multi-hop routing stack. We saw that the reliable time sync and the DSDV implementation in HSN (heterogeneous sensor network) routing stack performed the best, with percentage of successful transmissions averaging at 58.3% and 62.9% respectively. The nodes that were closer to the base station had a high success rate of 86.9% for HSN DSDV and 83% for reliable time sync.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125593385","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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