E. Soler, R. Villarroel, J. Trujillo, E. Fernández-Medina, M. Piattini
Data warehouses (DWs) contained high sensitive data, and therefore, it is essential to specify security measures from the early stages of the DW design and enforce them. Access control models for transactional (relational) databases, based on tables, columns and rows, are not appropriate for DWs. Instead, security and audit rules defined for DWs must be specified based on the multidimensional (MD) modeling used to design data warehouses. So far, very few approaches represent security measures in the conceptual modeling of data warehouses form the early stages of a DW project. Moreover these security measures cannot be directly represented in the relational model for data warehouses, thereby having a semantic gap between the conceptual and logical schemas. In this paper, we present an extension of the relational model to consider security and audit measures represented in the conceptual modeling. To accomplish this, we based on the relational package of the common warehouse metamodel (CWM) and extend it to properly represent all security and audit rules defined in the conceptual modelling of data warehouses. Finally, to show the benefit of our approach, we apply our proposal to a health care case study.
{"title":"Representing security and audit rules for data warehouses at the logical level by using the common warehouse metamodel","authors":"E. Soler, R. Villarroel, J. Trujillo, E. Fernández-Medina, M. Piattini","doi":"10.1109/ARES.2006.110","DOIUrl":"https://doi.org/10.1109/ARES.2006.110","url":null,"abstract":"Data warehouses (DWs) contained high sensitive data, and therefore, it is essential to specify security measures from the early stages of the DW design and enforce them. Access control models for transactional (relational) databases, based on tables, columns and rows, are not appropriate for DWs. Instead, security and audit rules defined for DWs must be specified based on the multidimensional (MD) modeling used to design data warehouses. So far, very few approaches represent security measures in the conceptual modeling of data warehouses form the early stages of a DW project. Moreover these security measures cannot be directly represented in the relational model for data warehouses, thereby having a semantic gap between the conceptual and logical schemas. In this paper, we present an extension of the relational model to consider security and audit measures represented in the conceptual modeling. To accomplish this, we based on the relational package of the common warehouse metamodel (CWM) and extend it to properly represent all security and audit rules defined in the conceptual modelling of data warehouses. Finally, to show the benefit of our approach, we apply our proposal to a health care case study.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128478661","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}
A. Sousa, A. Correia, F. Moura, J. Pereira, R. Oliveira
Partial replication is an alluring technique to ensure the reliability of very large and geographically distributed databases while, at the same time, offering good performance. By correctly exploiting access locality most transactions become confined to a small subset of the database replicas thus reducing processing, storage access and communication overhead associated with replication. The advantages of partial replication have however to be weighted against the added complexity that is required to manage it. In fact, if the chosen replica configuration prevents the local execution of transactions or if the overhead of consistency protocols offsets the savings of locality, potential gains cannot be realized. These issues are heavily dependent on the application used for evaluation and render simplistic benchmarks useless. In this paper, we present a detailed analysis of partial database state machine (PDBSM) replication by comparing alternative partial replication protocols with full replication. This is done using a realistic scenario based on a detailed network simulator and access patterns from an industry standard database benchmark. The results obtained allow us to identify the best configuration for typical online transaction processing applications.
{"title":"Evaluating certification protocols in the partial database state machine","authors":"A. Sousa, A. Correia, F. Moura, J. Pereira, R. Oliveira","doi":"10.1109/ARES.2006.60","DOIUrl":"https://doi.org/10.1109/ARES.2006.60","url":null,"abstract":"Partial replication is an alluring technique to ensure the reliability of very large and geographically distributed databases while, at the same time, offering good performance. By correctly exploiting access locality most transactions become confined to a small subset of the database replicas thus reducing processing, storage access and communication overhead associated with replication. The advantages of partial replication have however to be weighted against the added complexity that is required to manage it. In fact, if the chosen replica configuration prevents the local execution of transactions or if the overhead of consistency protocols offsets the savings of locality, potential gains cannot be realized. These issues are heavily dependent on the application used for evaluation and render simplistic benchmarks useless. In this paper, we present a detailed analysis of partial database state machine (PDBSM) replication by comparing alternative partial replication protocols with full replication. This is done using a realistic scenario based on a detailed network simulator and access patterns from an industry standard database benchmark. The results obtained allow us to identify the best configuration for typical online transaction processing applications.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129129187","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}
IP telephony has been adopted to replace the traditional circuit switch networks in various environments. Government Emergency Telephony Service (GETS) is one of the critical services currently provided in the traditional circuit switch network. GETS supports personnel from different organizations performing their critical missions including incidence response and prevention, national security, and emergency preparedness. Because of the convergent infrastructure for both voice and data, how to provide GETS over IP is one of the challenges for IP telephony to prove its flexibility and strength for large-scale critical services. In this study, we explore many aspects for providing IP-based GETS, such as availability, security, interoperability, and reliability. Based on IP multimedia subsystem (IMS) architecture, the requirements along with some analyses and recommendations are outlined to meet the strict demands for GETS in different convergent paradigms.
{"title":"Security analysis for IP-based Government Emergency Telephony Service","authors":"Feng Cao, S. Malik","doi":"10.1109/ARES.2006.124","DOIUrl":"https://doi.org/10.1109/ARES.2006.124","url":null,"abstract":"IP telephony has been adopted to replace the traditional circuit switch networks in various environments. Government Emergency Telephony Service (GETS) is one of the critical services currently provided in the traditional circuit switch network. GETS supports personnel from different organizations performing their critical missions including incidence response and prevention, national security, and emergency preparedness. Because of the convergent infrastructure for both voice and data, how to provide GETS over IP is one of the challenges for IP telephony to prove its flexibility and strength for large-scale critical services. In this study, we explore many aspects for providing IP-based GETS, such as availability, security, interoperability, and reliability. Based on IP multimedia subsystem (IMS) architecture, the requirements along with some analyses and recommendations are outlined to meet the strict demands for GETS in different convergent paradigms.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117305182","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}
C. Ciufudean, A. Graur, C. Filote, C. Turcu, V. Popa
Failure diagnosis in large and complex systems is a critical task. A discrete event system (DES) approach to the problem of failure diagnosis is presented in this paper. A classic solution to solve DES's diagnosis is a stochastic Petri nets. Unfortunately, the solution of a stochastic Petri net is severely restricted by the size of its underlying Markov chain. On the other hand, it has been shown that foraging behavior of ant colonies can give rise to the shortest path, which will reduce the state explosion of stochastic Petri net. Therefore, a new model of stochastic Petri net, based on foraging behavior of real ant colonies is introduced in this paper. This model can contribute to the diagnosis, the performance analysis and design of supervisory control systems.
{"title":"Diagnosis of complex systems using ant colony decision Petri nets","authors":"C. Ciufudean, A. Graur, C. Filote, C. Turcu, V. Popa","doi":"10.1109/ARES.2006.52","DOIUrl":"https://doi.org/10.1109/ARES.2006.52","url":null,"abstract":"Failure diagnosis in large and complex systems is a critical task. A discrete event system (DES) approach to the problem of failure diagnosis is presented in this paper. A classic solution to solve DES's diagnosis is a stochastic Petri nets. Unfortunately, the solution of a stochastic Petri net is severely restricted by the size of its underlying Markov chain. On the other hand, it has been shown that foraging behavior of ant colonies can give rise to the shortest path, which will reduce the state explosion of stochastic Petri net. Therefore, a new model of stochastic Petri net, based on foraging behavior of real ant colonies is introduced in this paper. This model can contribute to the diagnosis, the performance analysis and design of supervisory control systems.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"219 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115734053","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}
C. Webber, Maria de Fátima Webber do Prado Lima, Marcos E. Casa, A. Ribeiro
This article discusses security requirements for open distributed learning environments. Security is a critical issue, especially for highly interactive applications based on heterogeneous distributed architectures. In e-learning applications, security mechanisms have as their main purpose to protect against illegal access to information, so that confidentiality and integrity can be guaranteed. While a lot of effort in the e-learning domain has been put into delivering infrastructure and providing content, security issues have hardly ever been considered. Taking this fact into account, we have implemented a multiagent platform (the PMA3), which constitutes an open distributed infrastructure that addresses security issues. PMA3 is founded on multiagent principles and FIPA standards, and has been used in the development of e-learning environments.
{"title":"Adding security to a multiagent learning platform","authors":"C. Webber, Maria de Fátima Webber do Prado Lima, Marcos E. Casa, A. Ribeiro","doi":"10.1109/ARES.2006.24","DOIUrl":"https://doi.org/10.1109/ARES.2006.24","url":null,"abstract":"This article discusses security requirements for open distributed learning environments. Security is a critical issue, especially for highly interactive applications based on heterogeneous distributed architectures. In e-learning applications, security mechanisms have as their main purpose to protect against illegal access to information, so that confidentiality and integrity can be guaranteed. While a lot of effort in the e-learning domain has been put into delivering infrastructure and providing content, security issues have hardly ever been considered. Taking this fact into account, we have implemented a multiagent platform (the PMA3), which constitutes an open distributed infrastructure that addresses security issues. PMA3 is founded on multiagent principles and FIPA standards, and has been used in the development of e-learning environments.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125448191","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}
In this paper, we propose an approach to increase the reliability of RFID (radio frequency identification), not relying on the performance of each devices, but relying on a mechanism of entire networked system, which manages objects and/or people in the real world with RFID tags. We identified there exist many factors to reduce the accurate identifications of RFID tags, which results in the reduction of the total-system reliability. Moreover, we show the effect of our approach in diverse parameters such as the number of misidentifications, the length of transportations, the number of RFID readers.
{"title":"Systematic error detection for RFID reliability","authors":"Sozo Inoue, H. Yasuura, D. Hagiwara","doi":"10.1109/ARES.2006.128","DOIUrl":"https://doi.org/10.1109/ARES.2006.128","url":null,"abstract":"In this paper, we propose an approach to increase the reliability of RFID (radio frequency identification), not relying on the performance of each devices, but relying on a mechanism of entire networked system, which manages objects and/or people in the real world with RFID tags. We identified there exist many factors to reduce the accurate identifications of RFID tags, which results in the reduction of the total-system reliability. Moreover, we show the effect of our approach in diverse parameters such as the number of misidentifications, the length of transportations, the number of RFID readers.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127186876","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}
In this paper we present an IT continuity framework which deals with business continuity issues within organizations. The approach is based on an optimal mix between five groups of continuity measures that are associated with three risk clusters. Most organizations do have some continuity measures in case their level of operation is disrupted. However, these continuity measures are often isolated from each other and do not form an integral approach. They neither do cover the entire incident field. This framework supports the uniformity that exists among known continuity measures. Because of its generic nature, IT service providers can use the framework to organize their (existing) IT continuity portfolio in order to provide an optimal continuity solution to their customers.
{"title":"An integral IT continuity framework for undisrupted business operations","authors":"R. Helms, S. V. Oorschot, J. Herweijer, M. Plas","doi":"10.1109/ARES.2006.27","DOIUrl":"https://doi.org/10.1109/ARES.2006.27","url":null,"abstract":"In this paper we present an IT continuity framework which deals with business continuity issues within organizations. The approach is based on an optimal mix between five groups of continuity measures that are associated with three risk clusters. Most organizations do have some continuity measures in case their level of operation is disrupted. However, these continuity measures are often isolated from each other and do not form an integral approach. They neither do cover the entire incident field. This framework supports the uniformity that exists among known continuity measures. Because of its generic nature, IT service providers can use the framework to organize their (existing) IT continuity portfolio in order to provide an optimal continuity solution to their customers.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127518383","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}
R. Villarroel, E. Soler, E. Fernández-Medina, M. Piattini, J. Trujillo
In most real world data warehouses (DWs) projects, security aspects are issues that usually rely on DBMS administrators. We argue that the design of security aspects should be considered together with the conceptual modeling of DWs from the early stages of a DW project, and being able to attach user security information to the basic structures of a multidimensional (MD) model (e.g. dimensions, facts, attributes, and so on). In this way, we would be able to generate this information in a semi or automatic way into a target platform and the final DW will better suit user security requirements. In this paper, we will present an extension of the Unified Modeling Language (UML) using a UML profile to represent multidimensional and security aspects of our conceptual modeling. Our approach proposes the use of UML packages in order to group classes together into higher level units creating different levels of abstraction, and therefore, simplifying the final model. In this way, when modeling complex and large DWs systems, the designer is not restricted to use flat UML class diagrams. Finally, we would show an example to illustrate the applicability of our proposal.
{"title":"Representing levels of abstraction to facilitate the secure multidimensional modeling","authors":"R. Villarroel, E. Soler, E. Fernández-Medina, M. Piattini, J. Trujillo","doi":"10.1109/ARES.2006.109","DOIUrl":"https://doi.org/10.1109/ARES.2006.109","url":null,"abstract":"In most real world data warehouses (DWs) projects, security aspects are issues that usually rely on DBMS administrators. We argue that the design of security aspects should be considered together with the conceptual modeling of DWs from the early stages of a DW project, and being able to attach user security information to the basic structures of a multidimensional (MD) model (e.g. dimensions, facts, attributes, and so on). In this way, we would be able to generate this information in a semi or automatic way into a target platform and the final DW will better suit user security requirements. In this paper, we will present an extension of the Unified Modeling Language (UML) using a UML profile to represent multidimensional and security aspects of our conceptual modeling. Our approach proposes the use of UML packages in order to group classes together into higher level units creating different levels of abstraction, and therefore, simplifying the final model. In this way, when modeling complex and large DWs systems, the designer is not restricted to use flat UML class diagrams. Finally, we would show an example to illustrate the applicability of our proposal.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123768008","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}
There is an increasing demand for highly reliable systems in the safety conscious climate of today's world. When a fault does occur there are two desirable outcomes. Firstly, detection is required to discover whether functionality at a pre-determined level can be maintained and secondly, a necessary repair strategy is sought to minimise system disruption. Traditional focus on fault diagnosis has been through a sequential testing procedure or via real time mechanisms. The limitations have incorporated the issue of combining real time diagnosis; enabling fast analysis, with multiple fault causes. These issues are typical of critical situations within current complex system architectures. The diagnostic method suggested in this paper uses the digraph procedure, which represents the propagation of inputs through a system. The procedure involves generating a model; linking nodes referring to system parameters and determining the relationship(s) which connect the nodes. Fault detection occurs by means of tracing through the diagram. The method has been applied to a water tank system during steady state operation. Diagnosis is conducted by comparing readings from sensors in the system with expected readings, given the system mode of operation. The results demonstrate the effective use of this technique for fault diagnosis of the application system.
{"title":"Application of the digraph method in system fault diagnostics","authors":"","doi":"10.1109/ARES.2006.31","DOIUrl":"https://doi.org/10.1109/ARES.2006.31","url":null,"abstract":"There is an increasing demand for highly reliable systems in the safety conscious climate of today's world. When a fault does occur there are two desirable outcomes. Firstly, detection is required to discover whether functionality at a pre-determined level can be maintained and secondly, a necessary repair strategy is sought to minimise system disruption. Traditional focus on fault diagnosis has been through a sequential testing procedure or via real time mechanisms. The limitations have incorporated the issue of combining real time diagnosis; enabling fast analysis, with multiple fault causes. These issues are typical of critical situations within current complex system architectures. The diagnostic method suggested in this paper uses the digraph procedure, which represents the propagation of inputs through a system. The procedure involves generating a model; linking nodes referring to system parameters and determining the relationship(s) which connect the nodes. Fault detection occurs by means of tracing through the diagram. The method has been applied to a water tank system during steady state operation. Diagnosis is conducted by comparing readings from sensors in the system with expected readings, given the system mode of operation. The results demonstrate the effective use of this technique for fault diagnosis of the application system.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121620568","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}
Christian Schläger, Thomas Nowey, J. A. Montenegro
Authentication and Authorisation Infrastructures (AAIs) are gaining momentum throughout the Internet. Solutions have been proposed for various scenarios among them academia, grid computing, company networks, and above all eCommerce applications. Products and concepts vary in architecture, security features, target group, and usability containing different strengths and weaknesses. In addition security needs have changed in communication and business processes. Security on the Internet is no longer defined as only security measures for an eCommerce provider against an untrustworthy customer but also vice versa. Consequently, privacy, data canniness, and security are demands in this area. The authors define criteria for an eCommerce provider federation using an AAI with a maximum of privacy and flexibility. The criteria is derived concentrating on b2c eCommerce applications fulfilling the demands. In addition to best practices found, XACML policies and an attribute infrastructure are deployed. Among the evaluated AAIs are Shibboleth, Microsoft Passport, the Liberty Alliance Framework, and PERMIS.
{"title":"A reference model for Authentication and Authorisation Infrastructures respecting privacy and flexibility in b2c eCommerce","authors":"Christian Schläger, Thomas Nowey, J. A. Montenegro","doi":"10.1109/ARES.2006.13","DOIUrl":"https://doi.org/10.1109/ARES.2006.13","url":null,"abstract":"Authentication and Authorisation Infrastructures (AAIs) are gaining momentum throughout the Internet. Solutions have been proposed for various scenarios among them academia, grid computing, company networks, and above all eCommerce applications. Products and concepts vary in architecture, security features, target group, and usability containing different strengths and weaknesses. In addition security needs have changed in communication and business processes. Security on the Internet is no longer defined as only security measures for an eCommerce provider against an untrustworthy customer but also vice versa. Consequently, privacy, data canniness, and security are demands in this area. The authors define criteria for an eCommerce provider federation using an AAI with a maximum of privacy and flexibility. The criteria is derived concentrating on b2c eCommerce applications fulfilling the demands. In addition to best practices found, XACML policies and an attribute infrastructure are deployed. Among the evaluated AAIs are Shibboleth, Microsoft Passport, the Liberty Alliance Framework, and PERMIS.","PeriodicalId":106780,"journal":{"name":"First International Conference on Availability, Reliability and Security (ARES'06)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130646421","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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