Pub Date : 2005-06-15DOI: 10.1109/CONTEL.2005.185904
G. Zoric, I. Pandzic
In this paper we present a new method for mapping natural speech to lip shape animation in real time. The speech signal, represented by MFCC vectors, is classified into viseme classes using neural networks. The topology of neural networks is automatically configured using genetic algorithms. This eliminates the need for tedious manual neural network design by trial and error and considerably improves the viseme classification results. This method is available in real-time and offline mode, and is suitable for various applications. So, we propose the new multimedia services for mobile devices based on the lip sync system described.
{"title":"Automatic lip sync and its use in the new multimedia services for mobile devices","authors":"G. Zoric, I. Pandzic","doi":"10.1109/CONTEL.2005.185904","DOIUrl":"https://doi.org/10.1109/CONTEL.2005.185904","url":null,"abstract":"In this paper we present a new method for mapping natural speech to lip shape animation in real time. The speech signal, represented by MFCC vectors, is classified into viseme classes using neural networks. The topology of neural networks is automatically configured using genetic algorithms. This eliminates the need for tedious manual neural network design by trial and error and considerably improves the viseme classification results. This method is available in real-time and offline mode, and is suitable for various applications. So, we propose the new multimedia services for mobile devices based on the lip sync system described.","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127178752","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 : 2005-06-15DOI: 10.1109/CONTEL.2005.185971
E. Pek, Nikola Bogunović
The paper shows how predicate abstraction can be applied to protocol verification. Predicate abstraction is a method for automatic construction of an abstract state graph. The basic idea is to use n predicates, phi1,..., phin, defined on a concrete state space to generate an abstract state graph. Model checking is a formal verification technique which has been successfully applied to protocol verification. However, model checking can only be applied to finite state systems. Many interesting systems are infinite state or the number of states is so large that verification becomes infeasible. Predicate abstraction can be applied in the verification of infinite state systems (or large finite state systems). An abstract state graph created by predicate abstraction can be used for verification of safety properties using a model checker. We provide simple examples of protocol verification using predicate abstraction
{"title":"Predicate abstraction in protocol verification","authors":"E. Pek, Nikola Bogunović","doi":"10.1109/CONTEL.2005.185971","DOIUrl":"https://doi.org/10.1109/CONTEL.2005.185971","url":null,"abstract":"The paper shows how predicate abstraction can be applied to protocol verification. Predicate abstraction is a method for automatic construction of an abstract state graph. The basic idea is to use n predicates, phi1,..., phin, defined on a concrete state space to generate an abstract state graph. Model checking is a formal verification technique which has been successfully applied to protocol verification. However, model checking can only be applied to finite state systems. Many interesting systems are infinite state or the number of states is so large that verification becomes infeasible. Predicate abstraction can be applied in the verification of infinite state systems (or large finite state systems). An abstract state graph created by predicate abstraction can be used for verification of safety properties using a model checker. We provide simple examples of protocol verification using predicate abstraction","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133547121","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 : 2005-06-15DOI: 10.1109/CONTEL.2005.185996
A. Pakstas
Summary form only given. Capacity, reliability, and delay are three "magic words" used for describing concepts of computer network design. While capacity and delay are relatively well understood, this is not the case for reliability. The term reliability is often used interchangeably with availability and dependability. Increased redundancy in the network structure is often considered as an important, or even the only, way to achieve higher levels of reliability. The tutorial presents the role of reliability (in a broad sense) in network design. Factors affecting performability of the communications system are discussed. Reliability in the network design process, in the context of a systems approach to network design, is considered in more detail. Examples of calculations of reliability figures for different network designs are considered using the Delite tool. Reliability support in communications protocols is discussed. Examples of simulations and animations of network dynamics are presented using the ns-2 and nam tools
{"title":"Reliability issues in network planning","authors":"A. Pakstas","doi":"10.1109/CONTEL.2005.185996","DOIUrl":"https://doi.org/10.1109/CONTEL.2005.185996","url":null,"abstract":"Summary form only given. Capacity, reliability, and delay are three \"magic words\" used for describing concepts of computer network design. While capacity and delay are relatively well understood, this is not the case for reliability. The term reliability is often used interchangeably with availability and dependability. Increased redundancy in the network structure is often considered as an important, or even the only, way to achieve higher levels of reliability. The tutorial presents the role of reliability (in a broad sense) in network design. Factors affecting performability of the communications system are discussed. Reliability in the network design process, in the context of a systems approach to network design, is considered in more detail. Examples of calculations of reliability figures for different network designs are considered using the Delite tool. Reliability support in communications protocols is discussed. Examples of simulations and animations of network dynamics are presented using the ns-2 and nam tools","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"366 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133932527","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 : 2005-06-15DOI: 10.1109/CONTEL.2005.185851
M. Simsim, N. Khan, P. Rapajic
It is essential to have deep understanding of the mobile radio channel in particular for radio communication modeling and advanced technology system design. In his paper we employ the recently proposed Eccentro-Scattering physical channel model to derive the probability density functions (pdf) of Angle of Arrival (AOA) of the multipaths at Base Station (BS) from uniformly distributed scatterers for picocell, microcell, and macrocell environments. The Eccentro-Scattering model is easily employed to model any cellular environment with appropriate choice of few model parameters. This provides a unified approach to model all cellular environments that remained absent, so far. The derived formulas for the pdf of AOA of the multipaths at BS can be used further in performance assessment for smart antennas. uniform distribution and the Gaussian distribution. In uniformly distributed scattering region, scatterers are assumed to have constant density throughout the scattering area, while in Gaussian distributed scatterers, the majority of scattering points are situated close to MS and the density of scattering points decreases as the distance from MS increases. Assuming scatterers to be uniformly distributed simplifies the analysis and manipulation. These models are very specific to the corresponding environments, therefore, none of them can be considered as a general model that can be used to model all types of cellular environments. In (4), an elliptical model was proposed which could be altered to be used as a circular one, as well, with change in eccentricity of the ellipse in uniformly distributed scattering environment. The model was suitable for macrocell and quasi-macrocell
{"title":"Modeling spatial aspects of mobile channel in uniformly distributed scatterers","authors":"M. Simsim, N. Khan, P. Rapajic","doi":"10.1109/CONTEL.2005.185851","DOIUrl":"https://doi.org/10.1109/CONTEL.2005.185851","url":null,"abstract":"It is essential to have deep understanding of the mobile radio channel in particular for radio communication modeling and advanced technology system design. In his paper we employ the recently proposed Eccentro-Scattering physical channel model to derive the probability density functions (pdf) of Angle of Arrival (AOA) of the multipaths at Base Station (BS) from uniformly distributed scatterers for picocell, microcell, and macrocell environments. The Eccentro-Scattering model is easily employed to model any cellular environment with appropriate choice of few model parameters. This provides a unified approach to model all cellular environments that remained absent, so far. The derived formulas for the pdf of AOA of the multipaths at BS can be used further in performance assessment for smart antennas. uniform distribution and the Gaussian distribution. In uniformly distributed scattering region, scatterers are assumed to have constant density throughout the scattering area, while in Gaussian distributed scatterers, the majority of scattering points are situated close to MS and the density of scattering points decreases as the distance from MS increases. Assuming scatterers to be uniformly distributed simplifies the analysis and manipulation. These models are very specific to the corresponding environments, therefore, none of them can be considered as a general model that can be used to model all types of cellular environments. In (4), an elliptical model was proposed which could be altered to be used as a circular one, as well, with change in eccentricity of the ellipse in uniformly distributed scattering environment. The model was suitable for macrocell and quasi-macrocell","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134205950","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 : 2005-06-15DOI: 10.1109/CONTEL.2005.185933
S. Markovits, M. Lam, R. Braun
This paper focuses on providing an information model view of the Trouble component of the assurance domain. This is derived using an understanding of the TMF eTOM processes and the associated SID Information Model through its application to the Trouble processes. We begin by examining existing standards and adapt and/or derive entities which are used within these processes and develop some entities which are undefined or unavailable currently in the SID definitions. We describe an implementation that leverages the use of the SID information model principles to enhance Trouble assurance. The environment in which Telecommunication Service Providers (SP) operate is rapidly changing. Previously only technology centric, providing mainly voice connectivity the SP is now required to be more customer centric, facilitating anywhere anyhow anytime media rich services where voice is only one option in the user experience . Customers, demanding more are concerned with the effectiveness, timeliness and quality of services bound by commercial agreements. To meet these demands there is a requirement for SP to inter-work with all the stakeholders. These include not only the customer but Value Chain participants such content providers, service aggregators, partners, and technology providers. Trouble management is an integrating support component of assurance used to assist in service malfunction situations
{"title":"Information modeling of trouble: a service provider view","authors":"S. Markovits, M. Lam, R. Braun","doi":"10.1109/CONTEL.2005.185933","DOIUrl":"https://doi.org/10.1109/CONTEL.2005.185933","url":null,"abstract":"This paper focuses on providing an information model view of the Trouble component of the assurance domain. This is derived using an understanding of the TMF eTOM processes and the associated SID Information Model through its application to the Trouble processes. We begin by examining existing standards and adapt and/or derive entities which are used within these processes and develop some entities which are undefined or unavailable currently in the SID definitions. We describe an implementation that leverages the use of the SID information model principles to enhance Trouble assurance. The environment in which Telecommunication Service Providers (SP) operate is rapidly changing. Previously only technology centric, providing mainly voice connectivity the SP is now required to be more customer centric, facilitating anywhere anyhow anytime media rich services where voice is only one option in the user experience . Customers, demanding more are concerned with the effectiveness, timeliness and quality of services bound by commercial agreements. To meet these demands there is a requirement for SP to inter-work with all the stakeholders. These include not only the customer but Value Chain participants such content providers, service aggregators, partners, and technology providers. Trouble management is an integrating support component of assurance used to assist in service malfunction situations","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"515 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131625969","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 : 2005-06-15DOI: 10.1109/CONTEL.2005.185815
P. Savola, T. Chown
Site multihoming is a method by which an Internet end-site, for example an enterprise network, may connect to multiple service providers simultaneously. There are many reasons why multihoming is desirable, e.g. service resilience, network load balancing or provider independence. In the IPv4 Internet, multihoming has been achieved by use of relatively simple techniques, including networks advertising their network prefixes - whether such prefixes are independent of the Internet Service Providers (ISPs) or not - to the Internet global routing infrastructure. With the introduction of IPv6 the vast increase in the number of potential site prefixes means that for scalable site multihom- ing we cannot repeat such IPv4 multihoming practices. Thus new IPv6 multihoming solutions are required. In this paper we present an overview of currently proposed solutions and explore the challenges and motivations of site multihoming. Such a review is timely because multihoming remains a key perceived obstacle to widespread IPv6 deployment in mission-critical environments.
{"title":"A survey of IPv6 site multihoming proposals","authors":"P. Savola, T. Chown","doi":"10.1109/CONTEL.2005.185815","DOIUrl":"https://doi.org/10.1109/CONTEL.2005.185815","url":null,"abstract":"Site multihoming is a method by which an Internet end-site, for example an enterprise network, may connect to multiple service providers simultaneously. There are many reasons why multihoming is desirable, e.g. service resilience, network load balancing or provider independence. In the IPv4 Internet, multihoming has been achieved by use of relatively simple techniques, including networks advertising their network prefixes - whether such prefixes are independent of the Internet Service Providers (ISPs) or not - to the Internet global routing infrastructure. With the introduction of IPv6 the vast increase in the number of potential site prefixes means that for scalable site multihom- ing we cannot repeat such IPv4 multihoming practices. Thus new IPv6 multihoming solutions are required. In this paper we present an overview of currently proposed solutions and explore the challenges and motivations of site multihoming. Such a review is timely because multihoming remains a key perceived obstacle to widespread IPv6 deployment in mission-critical environments.","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133632928","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 : 2005-06-15DOI: 10.1109/CONTEL.2005.185978
H. Supić
Project management maturity models (PMMM) are a part of the PM development process, and present a relatively new concept. PMMMs are used to assess and plan strategically the PM development and required resources in an organization. Maturity models can also be used as a performance benchmark among different organizations and industries. Our fieldwork assessed the average PM maturity level of Croatian organizations, correlated the maturity with the basic organization characteristics, like ownership, market, size and industry, and explored the relation between PM process maturity and PM environment maturity. Croatian organizations are at low maturity levels (mostly 1 and 2 out of 5, average 1.75). There are differences in maturity among industries and the different sizes and markets in which organizations operate. The differences indicate that there is a link between the higher performance of an organization and its PM maturity level. The research showed that there is a very high correlation between the maturity of the PM processes and PM environment, and maturity can almost be considered the same from both perspectives. There is high recognition and high expectation regarding the development of PM practice within organizations. However, declining budgets and closed approach to maturing in PM might indicate hesitation. PM alone cannot improve the competitiveness of Croatian organizations, but its promotion should be an important element in the overall business environment
{"title":"Project management maturity of selected organizations in Croatia","authors":"H. Supić","doi":"10.1109/CONTEL.2005.185978","DOIUrl":"https://doi.org/10.1109/CONTEL.2005.185978","url":null,"abstract":"Project management maturity models (PMMM) are a part of the PM development process, and present a relatively new concept. PMMMs are used to assess and plan strategically the PM development and required resources in an organization. Maturity models can also be used as a performance benchmark among different organizations and industries. Our fieldwork assessed the average PM maturity level of Croatian organizations, correlated the maturity with the basic organization characteristics, like ownership, market, size and industry, and explored the relation between PM process maturity and PM environment maturity. Croatian organizations are at low maturity levels (mostly 1 and 2 out of 5, average 1.75). There are differences in maturity among industries and the different sizes and markets in which organizations operate. The differences indicate that there is a link between the higher performance of an organization and its PM maturity level. The research showed that there is a very high correlation between the maturity of the PM processes and PM environment, and maturity can almost be considered the same from both perspectives. There is high recognition and high expectation regarding the development of PM practice within organizations. However, declining budgets and closed approach to maturing in PM might indicate hesitation. PM alone cannot improve the competitiveness of Croatian organizations, but its promotion should be an important element in the overall business environment","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115271040","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 : 2005-06-15DOI: 10.1109/CONTEL.2005.185867
S. Krajnović, D. Huljenic
The paper analyses some of the critical knowledge management business factors and challenges in research and development centers within the ICT industry. In today's highly competitive world, knowledge has become the dominant source of competitive advantage. The paper stresses the importance of knowledge management for a long-term success of an organization. Furthermore, it elaborates on the critical importance of knowledge transfer and knowledge sharing culture. The challenges of international and multicultural knowledge transfers are presented and analyzed. The authors propose some basic principles for management and measurement of such knowledge transfers and corresponding transfer projects are proposed. The analysis is performed on the examples of ICT Ericsson research and development centers in Croatia and Ireland.
{"title":"An insight into challenges of international and multicultural knowledge transfers within ict industry","authors":"S. Krajnović, D. Huljenic","doi":"10.1109/CONTEL.2005.185867","DOIUrl":"https://doi.org/10.1109/CONTEL.2005.185867","url":null,"abstract":"The paper analyses some of the critical knowledge management business factors and challenges in research and development centers within the ICT industry. In today's highly competitive world, knowledge has become the dominant source of competitive advantage. The paper stresses the importance of knowledge management for a long-term success of an organization. Furthermore, it elaborates on the critical importance of knowledge transfer and knowledge sharing culture. The challenges of international and multicultural knowledge transfers are presented and analyzed. The authors propose some basic principles for management and measurement of such knowledge transfers and corresponding transfer projects are proposed. The analysis is performed on the examples of ICT Ericsson research and development centers in Croatia and Ireland.","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"162 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113972979","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 : 2005-06-15DOI: 10.1007/978-3-540-24663-3_8
P. Lorenz
{"title":"IP-oriented QoS in next generation networks: application to wireless networks","authors":"P. Lorenz","doi":"10.1007/978-3-540-24663-3_8","DOIUrl":"https://doi.org/10.1007/978-3-540-24663-3_8","url":null,"abstract":"","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120817041","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 : 2005-06-15DOI: 10.1109/CONTEL.2005.185956
Panu Hämäläinen, N. Liu, R. Sterling, Marko Hännikäinen, Timo Hämäläinen
This paper proposes a new Enhanced Security Layer (ESL) for Bluetooth. The security level is increased by replacing the encryption with AES and adding in- tegrity protection. As ESL is placed on the top of the standard controller interface, it can be integrated into any Bluetooth implementation. A prototype implementation of ESL is presented. The security processing is implemented in hardware for high performance. The design consumes fewer resources and has higher throughput (214 Mb/s) than the standard design. The programming interface supports straightforward application development.
{"title":"Design and implementation of an enhanced security layer for Bluetooth","authors":"Panu Hämäläinen, N. Liu, R. Sterling, Marko Hännikäinen, Timo Hämäläinen","doi":"10.1109/CONTEL.2005.185956","DOIUrl":"https://doi.org/10.1109/CONTEL.2005.185956","url":null,"abstract":"This paper proposes a new Enhanced Security Layer (ESL) for Bluetooth. The security level is increased by replacing the encryption with AES and adding in- tegrity protection. As ESL is placed on the top of the standard controller interface, it can be integrated into any Bluetooth implementation. A prototype implementation of ESL is presented. The security processing is implemented in hardware for high performance. The design consumes fewer resources and has higher throughput (214 Mb/s) than the standard design. The programming interface supports straightforward application development.","PeriodicalId":265923,"journal":{"name":"Proceedings of the 8th International Conference on Telecommunications, 2005. ConTEL 2005.","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116520313","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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