Pub Date : 2005-12-19DOI: 10.1109/COLCOM.2005.1651232
M. Rappa, Sarah E. Smith, A. Yacoub, L. Williams
Today, it is common for university instructors to compile links to online resources for the courses they teach, either as a supplement to a textbook, reading packet or, in some cases, as a replacement. Finding resources and keeping them up to date is time consuming. Instructors who teach similar subjects at different universities might benefit from working together to compile and share online resources for their courses. This paper describes a tool for sharing instructional materials called OpenSeminar. The purpose of OpenSeminar is to facilitate the structured compilation of open, online resources among a group of collaborators who share a common area of interest. Using OpenSeminar, the selection of resources can be customized and deployed to meet the specific needs of each professor. OpenSeminar adopts an editorial peer review framework to ensure content quality control. An illustration of OpenSeminar in the field of software engineering is provided
{"title":"OpenSeminar: Web-based Collaboration Tool for Open Educational Resources","authors":"M. Rappa, Sarah E. Smith, A. Yacoub, L. Williams","doi":"10.1109/COLCOM.2005.1651232","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651232","url":null,"abstract":"Today, it is common for university instructors to compile links to online resources for the courses they teach, either as a supplement to a textbook, reading packet or, in some cases, as a replacement. Finding resources and keeping them up to date is time consuming. Instructors who teach similar subjects at different universities might benefit from working together to compile and share online resources for their courses. This paper describes a tool for sharing instructional materials called OpenSeminar. The purpose of OpenSeminar is to facilitate the structured compilation of open, online resources among a group of collaborators who share a common area of interest. Using OpenSeminar, the selection of resources can be customized and deployed to meet the specific needs of each professor. OpenSeminar adopts an editorial peer review framework to ensure content quality control. An illustration of OpenSeminar in the field of software engineering is provided","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130694773","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 : 2005-12-19DOI: 10.1109/COLCOM.2005.1651217
Hisayoshi Sugiyama, T. Tsujioka, M. Murata
We investigated a collaboration scheme for rescue robots for reliable and effective operation of rescue systems using robots. The investigation focused on the collaborative movement of robots to maintain their wireless network. We propose classifying the robots into search robots and relay robots and using a behavior algorithm for their collaborative movement. According to the algorithm, search robots explore the disaster area and search for victims, whereas relay robots act as relay terminals within the network. Each robot classifies itself autonomously and repeatedly as the system operation progresses. We evaluated the performance of the victim detection system (a rescue system introduced in our previous paper) based on the proposed scheme by computer simulation. Its performance was improved compared with the case where every robot walked randomly in the disaster area and no classification occurred
{"title":"Collaborative movement of rescue robots for reliable and effective networking in disaster area","authors":"Hisayoshi Sugiyama, T. Tsujioka, M. Murata","doi":"10.1109/COLCOM.2005.1651217","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651217","url":null,"abstract":"We investigated a collaboration scheme for rescue robots for reliable and effective operation of rescue systems using robots. The investigation focused on the collaborative movement of robots to maintain their wireless network. We propose classifying the robots into search robots and relay robots and using a behavior algorithm for their collaborative movement. According to the algorithm, search robots explore the disaster area and search for victims, whereas relay robots act as relay terminals within the network. Each robot classifies itself autonomously and repeatedly as the system operation progresses. We evaluated the performance of the victim detection system (a rescue system introduced in our previous paper) based on the proposed scheme by computer simulation. Its performance was improved compared with the case where every robot walked randomly in the disaster area and no classification occurred","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115683601","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 : 2005-12-19DOI: 10.1109/COLCOM.2005.1651219
Steve Webb, Subramanyam Chitti, C. Pu
In this paper, we show experimentally that learning filters are able to classify large corpora of spam and legitimate email messages with a high degree of accuracy. The corpora in our experiments contain about half a million spam messages and a similar number of legitimate messages, making them two orders of magnitude larger than the corpora used in current research. The use of such large corpora represents a collaborative approach to spam filtering because the corpora combine spam and legitimate messages from many different sources. First, we show that this collaborative approach creates very accurate spam filters. Then, we introduce an effective attack against these filters which successfully degrades their ability to classify spam. Finally, we present an effective solution to the above attack which involves retraining the filters to accurately identify the attack messages
{"title":"An experimental evaluation of spam filter performance and robustness against attack","authors":"Steve Webb, Subramanyam Chitti, C. Pu","doi":"10.1109/COLCOM.2005.1651219","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651219","url":null,"abstract":"In this paper, we show experimentally that learning filters are able to classify large corpora of spam and legitimate email messages with a high degree of accuracy. The corpora in our experiments contain about half a million spam messages and a similar number of legitimate messages, making them two orders of magnitude larger than the corpora used in current research. The use of such large corpora represents a collaborative approach to spam filtering because the corpora combine spam and legitimate messages from many different sources. First, we show that this collaborative approach creates very accurate spam filters. Then, we introduce an effective attack against these filters which successfully degrades their ability to classify spam. Finally, we present an effective solution to the above attack which involves retraining the filters to accurately identify the attack messages","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121310258","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 : 2005-12-19DOI: 10.1109/COLCOM.2005.1651220
Fuwen Liu, H. König
Confidentiality is a key demand for many collaborative applications in the Internet, e.g. business meetings. In a more and more mobile society there is an increasing need of spontaneous meetings in ad hoc environments, often with changing partners. To assure confidentiality of such meetings the partners have to agree upon a common secret key for encrypting their communication. While centralized collaborative systems provide practicable solutions for this, it still represents a challenging task in decentralized systems using the peer-to-peer paradigm. In this paper we present a simple key distribution protocol, called VTKD, which was especially designed for small dynamic peer groups. It consists of two parts: a mutual authentication of the partners and a secure key renewal. The protocol uses a virtual token to determine the partner responsible for the key generation and distribution procedure. VTKD fulfills the relevant demands concerning group key exchange and is more efficient related to key renewal delay than existing key exchange protocols
{"title":"Secure and efficient key distribution for collaborative applications","authors":"Fuwen Liu, H. König","doi":"10.1109/COLCOM.2005.1651220","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651220","url":null,"abstract":"Confidentiality is a key demand for many collaborative applications in the Internet, e.g. business meetings. In a more and more mobile society there is an increasing need of spontaneous meetings in ad hoc environments, often with changing partners. To assure confidentiality of such meetings the partners have to agree upon a common secret key for encrypting their communication. While centralized collaborative systems provide practicable solutions for this, it still represents a challenging task in decentralized systems using the peer-to-peer paradigm. In this paper we present a simple key distribution protocol, called VTKD, which was especially designed for small dynamic peer groups. It consists of two parts: a mutual authentication of the partners and a secure key renewal. The protocol uses a virtual token to determine the partner responsible for the key generation and distribution procedure. VTKD fulfills the relevant demands concerning group key exchange and is more efficient related to key renewal delay than existing key exchange protocols","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123232927","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 : 2005-12-19DOI: 10.1109/COLCOM.2005.1651238
J. Quemada, T. Miguel, Santiago Pavón, G. Huecas, T. Robles, J. Salvachúa, Diego Andres Acosta Ortiz, Vicente Sirvent, Fernando Escribano, J. Sedano
Isabel is a P2P like multipoint group collaboration tool for the Internet, which implements an innovative service concept for synchronous collaborations based on a flexible and programmable floor control. This approach leads to a more natural and effective management of collaboration sessions. The flexible and programmable floor control incorporates the experience gained in many years of service trials with real users in distributed conferences, classrooms or meetings. The main conclusion after all those trials is that services should use more or less the same media components (audio, video or application sharing), but differ in the floor control model used. The flexible floor control is especially well suited for multipoint audience interconnection in distributed classrooms, conferences, meetings, etc. The development of Isabel started in 1993 for the distribution of the RACE Summer Schools on Advanced Broadband Communication (ABC93-6) where the early versions of this service concept were developed and tuned. The effectiveness of the Isabel service concept has been proven and enhanced since then in many other distributed events, such as Global360x, IDC9x, Global IPv6 Summitts, Telecom I+D, etc. The adaptation of Isabel to the broadband Internet (including VPNs, IPv4/IPv6 transition scenarios, mixtures of unicast and multicast) has reached maturity recently
{"title":"Isabel: an application for real time collaboration with a flexible floor control","authors":"J. Quemada, T. Miguel, Santiago Pavón, G. Huecas, T. Robles, J. Salvachúa, Diego Andres Acosta Ortiz, Vicente Sirvent, Fernando Escribano, J. Sedano","doi":"10.1109/COLCOM.2005.1651238","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651238","url":null,"abstract":"Isabel is a P2P like multipoint group collaboration tool for the Internet, which implements an innovative service concept for synchronous collaborations based on a flexible and programmable floor control. This approach leads to a more natural and effective management of collaboration sessions. The flexible and programmable floor control incorporates the experience gained in many years of service trials with real users in distributed conferences, classrooms or meetings. The main conclusion after all those trials is that services should use more or less the same media components (audio, video or application sharing), but differ in the floor control model used. The flexible floor control is especially well suited for multipoint audience interconnection in distributed classrooms, conferences, meetings, etc. The development of Isabel started in 1993 for the distribution of the RACE Summer Schools on Advanced Broadband Communication (ABC93-6) where the early versions of this service concept were developed and tuned. The effectiveness of the Isabel service concept has been proven and enhanced since then in many other distributed events, such as Global360x, IDC9x, Global IPv6 Summitts, Telecom I+D, etc. The adaptation of Isabel to the broadband Internet (including VPNs, IPv4/IPv6 transition scenarios, mixtures of unicast and multicast) has reached maturity recently","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129615839","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 : 2005-12-19DOI: 10.1109/COLCOM.2005.1651243
Haifeng Shen, Chengzheng Sun
With the rapid popularity of computer networks, collaborative document writing becomes increasingly desirable in recent years. In practice, collaborative writing is more likely to be done in an asynchronous manner, where collaborators usually work in parallel with different time schedules and are not present at the same time. Merging is the key technique to support concurrent writing and textual merging remains the primary and the only successful merging function to date. However, most of existing systems support constrained textual merging for the simplicity of the underling merging algorithms. In this paper, we propose a flexible operation-based syntactic textual merging algorithm that is capable of reconciling changes made in parallel by different users according to the syntax of the files to be merged or user-specified merging policies. Moreover, this syntax-based reconciliation algorithm is able to preserve the intentions of individual changes
{"title":"Syntax-based reconciliation for asynchronous collaborative writing","authors":"Haifeng Shen, Chengzheng Sun","doi":"10.1109/COLCOM.2005.1651243","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651243","url":null,"abstract":"With the rapid popularity of computer networks, collaborative document writing becomes increasingly desirable in recent years. In practice, collaborative writing is more likely to be done in an asynchronous manner, where collaborators usually work in parallel with different time schedules and are not present at the same time. Merging is the key technique to support concurrent writing and textual merging remains the primary and the only successful merging function to date. However, most of existing systems support constrained textual merging for the simplicity of the underling merging algorithms. In this paper, we propose a flexible operation-based syntactic textual merging algorithm that is capable of reconciling changes made in parallel by different users according to the syntax of the files to be merged or user-specified merging policies. Moreover, this syntax-based reconciliation algorithm is able to preserve the intentions of individual changes","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128619903","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 : 2005-12-19DOI: 10.1109/COLCOM.2005.1651240
S. Banik, S. Radhakrishnan, T. Zheng, C. Sekharan
Computer supported collaborative applications on overlay networks are gaining popularity among users who are geographically dispersed. Examples of these kinds of applications include video-conferencing, collaborative design and simulation, distance learning, and online games. One of the important issues in collaborative applications is floor control wherein the end-users coordinate among themselves to gain exclusive access to the communication channel. An end-user who wins the floor, sends message to all other participating end-users. In this paper, to solve the floor control problem we present an implementation and evaluation of ALOHA and distributed queue dual bus (DQDB) distributed MAC (medium access control) protocols on overlay networks. As an initial step in the implementation of these MAC protocols, we propose an algorithm to construct an efficient communication channel among the Network Service Nodes (NSNs) in the overlay network. We also show that our implementation scheme (first one among decentralized floor control protocols) preserves the causal ordering of messages. We compare the efficiencies of the proposed implementation of floor control protocols using an analytical model that is verified using extensive simulation experiments
{"title":"Distributed floor control protocols for computer collaborative applications on overlay networks","authors":"S. Banik, S. Radhakrishnan, T. Zheng, C. Sekharan","doi":"10.1109/COLCOM.2005.1651240","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651240","url":null,"abstract":"Computer supported collaborative applications on overlay networks are gaining popularity among users who are geographically dispersed. Examples of these kinds of applications include video-conferencing, collaborative design and simulation, distance learning, and online games. One of the important issues in collaborative applications is floor control wherein the end-users coordinate among themselves to gain exclusive access to the communication channel. An end-user who wins the floor, sends message to all other participating end-users. In this paper, to solve the floor control problem we present an implementation and evaluation of ALOHA and distributed queue dual bus (DQDB) distributed MAC (medium access control) protocols on overlay networks. As an initial step in the implementation of these MAC protocols, we propose an algorithm to construct an efficient communication channel among the Network Service Nodes (NSNs) in the overlay network. We also show that our implementation scheme (first one among decentralized floor control protocols) preserves the causal ordering of messages. We compare the efficiencies of the proposed implementation of floor control protocols using an analytical model that is verified using extensive simulation experiments","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127686047","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 : 2005-12-19DOI: 10.1109/COLCOM.2005.1651207
C. Pu
{"title":"Collaborative Enterprise Applications","authors":"C. Pu","doi":"10.1109/COLCOM.2005.1651207","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651207","url":null,"abstract":"","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122814055","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 : 2005-12-19DOI: 10.1109/COLCOM.2005.1651242
S. Xia, David Sun, Chengzheng Sun, David Chen
Object grouping is an effective means for managing the complexity in graphics editing. However, research on collaborative object grouping has not been adequate. In this paper, we contribute a novel collaborative object grouping technique, called CoGroup. CoGroup can achieve maximal combined effects among compatible operations and preserve all users' work in the face of conflict without the overhead of undoing and redoing conflict operations as in existing serialization approaches. CoGroup has been implemented in collaborative word processing (CoWord) and slide authoring (CoPowerPoint) systems and is generally applicable to a range of off-the-shelf commercial graphics applications, particularly CAD/CASE tools
{"title":"Collaborative object grouping in graphics editing systems","authors":"S. Xia, David Sun, Chengzheng Sun, David Chen","doi":"10.1109/COLCOM.2005.1651242","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651242","url":null,"abstract":"Object grouping is an effective means for managing the complexity in graphics editing. However, research on collaborative object grouping has not been adequate. In this paper, we contribute a novel collaborative object grouping technique, called CoGroup. CoGroup can achieve maximal combined effects among compatible operations and preserve all users' work in the face of conflict without the overhead of undoing and redoing conflict operations as in existing serialization approaches. CoGroup has been implemented in collaborative word processing (CoWord) and slide authoring (CoPowerPoint) systems and is generally applicable to a range of off-the-shelf commercial graphics applications, particularly CAD/CASE tools","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116435807","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 : 2005-12-19DOI: 10.1109/COLCOM.2005.1651237
Manuel Rodriguez-Perez, O. Esparza, J. L. Muñoz
Peer-to-peer systems consist of groups of nodes acting as clients and servers. These groups of nodes communicate directly among themselves through wide-area networks. Some of the benefits of fully distributed peer-to-peer systems are scalability, resource aggregation and interoperability without any administration cost or centralized infrastructure support. In this context, reputation schemes aid the service requesters to choose the proper resource provider and to prevent malicious behaviors. This paper analyzes reputation management in fully distributed peer-to-peer systems. This paper discusses the main issues that a reputation framework must address and analyzes the most representative distributed reputation systems. This paper also discusses the main advantages and drawbacks of each proposal in relation to peer-to-peer reputation system requirements
{"title":"Analysis of peer-to-peer distributed reputation schemes","authors":"Manuel Rodriguez-Perez, O. Esparza, J. L. Muñoz","doi":"10.1109/COLCOM.2005.1651237","DOIUrl":"https://doi.org/10.1109/COLCOM.2005.1651237","url":null,"abstract":"Peer-to-peer systems consist of groups of nodes acting as clients and servers. These groups of nodes communicate directly among themselves through wide-area networks. Some of the benefits of fully distributed peer-to-peer systems are scalability, resource aggregation and interoperability without any administration cost or centralized infrastructure support. In this context, reputation schemes aid the service requesters to choose the proper resource provider and to prevent malicious behaviors. This paper analyzes reputation management in fully distributed peer-to-peer systems. This paper discusses the main issues that a reputation framework must address and analyzes the most representative distributed reputation systems. This paper also discusses the main advantages and drawbacks of each proposal in relation to peer-to-peer reputation system requirements","PeriodicalId":365186,"journal":{"name":"2005 International Conference on Collaborative Computing: Networking, Applications and Worksharing","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126200943","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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