Pub Date : 2005-07-11DOI: 10.1109/PERSER.2005.1506423
A. Gopalan, T. Znati, Panos K. Chrysanthis
Realizing the potential of pervasive computing will be predicated upon the availability of a flexible, mobility-aware infrastructure and technologies to support seamless service management, provisioning and delivery. Despite advances in routing and media access control technologies, little progress has been made toward large-scale deployment of services and applications in pervasive and ubiquitous environments. The lack of a fixed infrastructure, coupled with the time-varying characteristics of the underlying network topology, makes service delivery challenging. This paper addresses the need for new service models and proposes a mobility-aware service architecture to support pervasive service provisioning and delivery in an infrastructureless environment. The proposed methodology centers around the concepts of virtual homes and mobility signatures, and decouples service discovery from current location of the server. We discuss the main functionalities of the proposed architecture and describe the underlying service discovery mechanisms and protocols. We also present a novel, piece-meal, location-driven traffic forwarding algorithm, and analyze its performance using a simulation-based study. The results show that the algorithm exhibits good performance for a variety of network environments.
{"title":"Structuring pervasive services in infrastructureless networks","authors":"A. Gopalan, T. Znati, Panos K. Chrysanthis","doi":"10.1109/PERSER.2005.1506423","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506423","url":null,"abstract":"Realizing the potential of pervasive computing will be predicated upon the availability of a flexible, mobility-aware infrastructure and technologies to support seamless service management, provisioning and delivery. Despite advances in routing and media access control technologies, little progress has been made toward large-scale deployment of services and applications in pervasive and ubiquitous environments. The lack of a fixed infrastructure, coupled with the time-varying characteristics of the underlying network topology, makes service delivery challenging. This paper addresses the need for new service models and proposes a mobility-aware service architecture to support pervasive service provisioning and delivery in an infrastructureless environment. The proposed methodology centers around the concepts of virtual homes and mobility signatures, and decouples service discovery from current location of the server. We discuss the main functionalities of the proposed architecture and describe the underlying service discovery mechanisms and protocols. We also present a novel, piece-meal, location-driven traffic forwarding algorithm, and analyze its performance using a simulation-based study. The results show that the algorithm exhibits good performance for a variety of network environments.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"10 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":"126098502","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: 10.1108/17427370580000129
M. Handte, C. Becker, K. Rothermel
Pervasive computing envisions seamless support for user tasks through cooperating devices that are present in an environment. Fluctuating availability of devices, induced by mobility and failures, requires mechanisms and algorithms that allow applications to adapt to changing environmental conditions without user intervention. To ease the development of adaptive applications, we have proposed the peer-based component system PCOM. This system provides fundamental mechanisms to support the automated composition of applications at runtime. In this paper, we discuss the requirements on peer-based automatic configuration of pervasive applications and present an approach based on distributed constraint satisfaction. The resulting algorithm configures applications in the presence of strictly limited resources. To show the feasibility of the approach, we have integrated the algorithm into PCOM and provide an evaluation based on simulation and measurements.
{"title":"Peer-based automatic configuration of pervasive applications","authors":"M. Handte, C. Becker, K. Rothermel","doi":"10.1108/17427370580000129","DOIUrl":"https://doi.org/10.1108/17427370580000129","url":null,"abstract":"Pervasive computing envisions seamless support for user tasks through cooperating devices that are present in an environment. Fluctuating availability of devices, induced by mobility and failures, requires mechanisms and algorithms that allow applications to adapt to changing environmental conditions without user intervention. To ease the development of adaptive applications, we have proposed the peer-based component system PCOM. This system provides fundamental mechanisms to support the automated composition of applications at runtime. In this paper, we discuss the requirements on peer-based automatic configuration of pervasive applications and present an approach based on distributed constraint satisfaction. The resulting algorithm configures applications in the presence of strictly limited resources. To show the feasibility of the approach, we have integrated the algorithm into PCOM and provide an evaluation based on simulation and measurements.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"13 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":"114100571","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.2005.1506556
Maria Uther, Pushpendra Singh, James Uther
In this paper, we present a mobile adaptive computer-assisted language learning (MAC) software aimed to help Japanese-English speakers in perceptually distinguishing the non-native /r/ vs. /l/ English phonemic contrast with a view to improving their own English pronunciation. MAC is implemented in Java (J2ME), allowing the software to be used on a wide range of mobile devices including most recent mobile phones. This allows the application to be used anywhere and anytime, on devices that learners would commonly already own.
{"title":"Mobile adaptive CALL (MAC): an adaptive s/w for computer assisted language learning","authors":"Maria Uther, Pushpendra Singh, James Uther","doi":"10.1109/PERSER.2005.1506556","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506556","url":null,"abstract":"In this paper, we present a mobile adaptive computer-assisted language learning (MAC) software aimed to help Japanese-English speakers in perceptually distinguishing the non-native /r/ vs. /l/ English phonemic contrast with a view to improving their own English pronunciation. MAC is implemented in Java (J2ME), allowing the software to be used on a wide range of mobile devices including most recent mobile phones. This allows the application to be used anywhere and anytime, on devices that learners would commonly already own.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"96 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":"115803190","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.2005.1506559
Theodoros Anagnostopoulos, C. Anagnostopoulos, S. Hadjiefthymiades
The pervasive computing paradigm has raised issues such as conceptual semantic descriptions and ambient management of information resources. The probabilistic theory on the other hand provides uncertain knowledge representation schemes that are semantically inefficient. However, security models related to attacks exploits both semantic and probabilistic modeling. Issues such as attack prediction and classification of attacker's intentions are of high importance in IDS environments. In this paper we propose a novel Breadth and Depth Bayesian classifier and an inference probabilistic algorithm. The inference algorithm is applied over well defined conceptual information integrated in a hybrid IDS by means of ontologies.
{"title":"Enabling attack behavior prediction in ubiquitous environments","authors":"Theodoros Anagnostopoulos, C. Anagnostopoulos, S. Hadjiefthymiades","doi":"10.1109/PERSER.2005.1506559","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506559","url":null,"abstract":"The pervasive computing paradigm has raised issues such as conceptual semantic descriptions and ambient management of information resources. The probabilistic theory on the other hand provides uncertain knowledge representation schemes that are semantically inefficient. However, security models related to attacks exploits both semantic and probabilistic modeling. Issues such as attack prediction and classification of attacker's intentions are of high importance in IDS environments. In this paper we propose a novel Breadth and Depth Bayesian classifier and an inference probabilistic algorithm. The inference algorithm is applied over well defined conceptual information integrated in a hybrid IDS by means of ontologies.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"40 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":"133406228","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.2005.1506394
H. Kido, Y. Yanagisawa, T. Satoh
Recently, highly accurate positioning devices enable us to provide various types of location-based services. On the other hand, because such position data include deeply personal information, the protection of location privacy is one of the most significant problems in location-based services. In this paper, we propose an anonymous communication technique to protect the location privacy of the users of location-based services. In our proposed technique, such users generate several false position data (dummies) to send to service providers with the true position data of users. Because service providers cannot distinguish the true position data, user location privacy is protected. We also describe a cost reduction technique for communication between a client and a server. Moreover, we conducted performance study experiments on our proposed technique using practical position data. As a result of the experiments, we observed that our proposed technique protects the location privacy of people and can sufficiently reduce communication costs so that our communication techniques can be applied in practical location-based services.
{"title":"An anonymous communication technique using dummies for location-based services","authors":"H. Kido, Y. Yanagisawa, T. Satoh","doi":"10.1109/PERSER.2005.1506394","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506394","url":null,"abstract":"Recently, highly accurate positioning devices enable us to provide various types of location-based services. On the other hand, because such position data include deeply personal information, the protection of location privacy is one of the most significant problems in location-based services. In this paper, we propose an anonymous communication technique to protect the location privacy of the users of location-based services. In our proposed technique, such users generate several false position data (dummies) to send to service providers with the true position data of users. Because service providers cannot distinguish the true position data, user location privacy is protected. We also describe a cost reduction technique for communication between a client and a server. Moreover, we conducted performance study experiments on our proposed technique using practical position data. As a result of the experiments, we observed that our proposed technique protects the location privacy of people and can sufficiently reduce communication costs so that our communication techniques can be applied in practical location-based services.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"49 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":"133928975","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.2005.1506387
R. Baldoni, R. Beraldi, G. Cugola, Matteo Migliavacca, Leonardo Querzoni
The decoupling and asynchrony properties of the content-based publish-subscribe paradigm makes it very appealing for dynamic wireless networks, like those that often occur in pervasive computing scenarios. Unfortunately, none of the currently available content-based publish-subscribe middleware fit the requirements of such extreme scenarios in which the network is subject to very frequent topological reconfigurations due to the mobility of nodes. In this paper we propose a protocol for content-based message dissemination tailored to mobile ad hoc networks (MANETs) with frequent topological changes. Message routing occurs without the support of any network-wide dispatching infrastructure thus eliminating the issue of maintaining such logical topology on top of a time varying physical topology. The paper reports an extensive simulation study, which provides numerical evidence of the effectiveness of the approach.
{"title":"Structure-less content-based routing in mobile ad hoc networks","authors":"R. Baldoni, R. Beraldi, G. Cugola, Matteo Migliavacca, Leonardo Querzoni","doi":"10.1109/PERSER.2005.1506387","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506387","url":null,"abstract":"The decoupling and asynchrony properties of the content-based publish-subscribe paradigm makes it very appealing for dynamic wireless networks, like those that often occur in pervasive computing scenarios. Unfortunately, none of the currently available content-based publish-subscribe middleware fit the requirements of such extreme scenarios in which the network is subject to very frequent topological reconfigurations due to the mobility of nodes. In this paper we propose a protocol for content-based message dissemination tailored to mobile ad hoc networks (MANETs) with frequent topological changes. Message routing occurs without the support of any network-wide dispatching infrastructure thus eliminating the issue of maintaining such logical topology on top of a time varying physical topology. The paper reports an extensive simulation study, which provides numerical evidence of the effectiveness of the approach.","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":"117298331","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.2005.1506553
Fernando Siqueira, Angelo Brayner
This paper presents a context-aware tool for remote database administration that is executed in mobile devices, MDBA (mobile database administrator). The MDBA enables database administrators (DBAs) to perform their tasks by automatically identifying databases and the wireless communication structure of a given mobile computational environment. The proposed tool has properties, which integrate features of mobile computation pervasive computation paradigms and introduces also the notion of remote database administration, which is supported by a new computational paradigm, denoted ubiquitous computation. Therefore, the MDBA tool provides database administration services anywhere and anytime. Furthermore, the MDBA enables DBAs to manage databases residing in mobile hosts or fixed hosts.
{"title":"Towards database administration in pervasive computing environment","authors":"Fernando Siqueira, Angelo Brayner","doi":"10.1109/PERSER.2005.1506553","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506553","url":null,"abstract":"This paper presents a context-aware tool for remote database administration that is executed in mobile devices, MDBA (mobile database administrator). The MDBA enables database administrators (DBAs) to perform their tasks by automatically identifying databases and the wireless communication structure of a given mobile computational environment. The proposed tool has properties, which integrate features of mobile computation pervasive computation paradigms and introduces also the notion of remote database administration, which is supported by a new computational paradigm, denoted ubiquitous computation. Therefore, the MDBA tool provides database administration services anywhere and anytime. Furthermore, the MDBA enables DBAs to manage databases residing in mobile hosts or fixed hosts.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"6 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":"124646565","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.2005.1506413
Oliver Maye
The last decade has seen location-based services as the rising star on the firmament of pervasive computing. Infrastructure-based middleware platforms provide a scalable way to support those applications. At the mobile side, event-driven control flow dominates the software design. Location events like "User A is NEAR user B" and their logical combinations must be processed effectively. We suggest a scalable event filtering strategy by separating the evaluation of basic elements from the computation of the remaining logical expression and by dynamically distributing the logic-computing unit throughout the platform infrastructure. Distribution is made according to the user's positions. In the best case, this leads to fully distributed processing. In the worst case, the scheme falls back to a quasi-centralized design. Measured performance of a prototype implementation in Java was at 355 notifications per second. Compared to a centralized design, this is an improvement by roughly a factor of 70.
{"title":"An efficient strategy of processing distributed location based events","authors":"Oliver Maye","doi":"10.1109/PERSER.2005.1506413","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506413","url":null,"abstract":"The last decade has seen location-based services as the rising star on the firmament of pervasive computing. Infrastructure-based middleware platforms provide a scalable way to support those applications. At the mobile side, event-driven control flow dominates the software design. Location events like \"User A is NEAR user B\" and their logical combinations must be processed effectively. We suggest a scalable event filtering strategy by separating the evaluation of basic elements from the computation of the remaining logical expression and by dynamically distributing the logic-computing unit throughout the platform infrastructure. Distribution is made according to the user's positions. In the best case, this leads to fully distributed processing. In the worst case, the scheme falls back to a quasi-centralized design. Measured performance of a prototype implementation in Java was at 355 notifications per second. Compared to a centralized design, this is an improvement by roughly a factor of 70.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"86 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":"124818090","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.2005.1506548
G. Anastasi, A. Passarella, M. Conti, E. Gregori, Luciana Pelusi
Smart environments are becoming popular and even more users are approaching their services through portable devices like PDAs, laptops, and mobile phones. These devices are generally battery-fed, thus, energy efficiency is surely a critical factor for the deployment of pervasive services. In this paper we focus on the diffusion of multimedia streaming services in smart environments. Specifically, we investigate scenarios where mobile users who have a Wi-Fi access to the Internet receive audio files from remote streaming servers. We address energy saving by including periodic transmission interruptions in the schedule of audio frames at the server, so that the network interface card at the receiver can be set to a low-power consuming state. Experimentation on a software prototype shows that our solution makes possible an energy saving ranging from 76% to 91% (depending on the data rate and the background traffic) of the total consumption due to the network interface. It also preserves a good user level QoS.
{"title":"A power-aware multimedia streaming protocol for mobile users","authors":"G. Anastasi, A. Passarella, M. Conti, E. Gregori, Luciana Pelusi","doi":"10.1109/PERSER.2005.1506548","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506548","url":null,"abstract":"Smart environments are becoming popular and even more users are approaching their services through portable devices like PDAs, laptops, and mobile phones. These devices are generally battery-fed, thus, energy efficiency is surely a critical factor for the deployment of pervasive services. In this paper we focus on the diffusion of multimedia streaming services in smart environments. Specifically, we investigate scenarios where mobile users who have a Wi-Fi access to the Internet receive audio files from remote streaming servers. We address energy saving by including periodic transmission interruptions in the schedule of audio frames at the server, so that the network interface card at the receiver can be set to a low-power consuming state. Experimentation on a software prototype shows that our solution makes possible an energy saving ranging from 76% to 91% (depending on the data rate and the background traffic) of the total consumption due to the network interface. It also preserves a good user level QoS.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"48 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":"123605839","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.2005.1506419
A. Zarras, Panos Vassiliadis, E. Pitoura
In this paper, we present CONSERV - a middleware infrastructure for the development of virtual databases in pervasive computing environments. CONSERV provides an SQL front-end for posing and processing queries on information provided by ad-hoc communities of Web services hosted by peers that arbitrarily join and leave the system. The cornerstone of the proposed infrastructure is the fact that we replace the traditional treatment of databases as persistent collections of records by the assumption that a database relation is a collection of records dynamically compiled from such ad-hoc sets of peers. Each peer offers data to the relations through a workflow of Web services. Another aspect of our approach is that we confine query processing over specific sets of peers that we call communities. Communities are defined based on the current context of the peer initiating each query. Since our infrastructure departs from the traditional query processing strategies, we discuss query processing as customized in CONSERV.
{"title":"Query management over ad-hoc communities of Web services","authors":"A. Zarras, Panos Vassiliadis, E. Pitoura","doi":"10.1109/PERSER.2005.1506419","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506419","url":null,"abstract":"In this paper, we present CONSERV - a middleware infrastructure for the development of virtual databases in pervasive computing environments. CONSERV provides an SQL front-end for posing and processing queries on information provided by ad-hoc communities of Web services hosted by peers that arbitrarily join and leave the system. The cornerstone of the proposed infrastructure is the fact that we replace the traditional treatment of databases as persistent collections of records by the assumption that a database relation is a collection of records dynamically compiled from such ad-hoc sets of peers. Each peer offers data to the relations through a workflow of Web services. Another aspect of our approach is that we confine query processing over specific sets of peers that we call communities. Communities are defined based on the current context of the peer initiating each query. Since our infrastructure departs from the traditional query processing strategies, we discuss query processing as customized in CONSERV.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"3 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":"123835210","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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