Rozprawy doktorskie: „Ubiquitous Network”

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Sareh, Said Adel Mounir. "Ubiquitous sensor network in the NGN environment". Thesis, Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0016/document.

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Ubiquitous Sensor Network (USN) est un réseau conceptuel construit sur des réseaux physiques existantes. Il se sert des données détectées et fournit des services de connaissances à quiconque, n'importe où et à tout moment, et où l'information est générée en utilisant la sensibilité au contexte. Dispositifs et USN portables intelligents émergent rapidement en offrant de nombreux services fiables facilitant la vie des gens. Ces petits terminaux et terminaux très utiles besoin d'un substrat de communication globale pour fournir un service complet de l'utilisateur final global. En 2010, ITU -T a fourni les exigences pour supporter des applications et services USN dans le Next Generation Network (NGN) de l'environnement d'exploiter les avantages du réseau de base. L'un des principaux marchés prometteurs pour l'application et les services USN est la e- santé. Il fournit le suivi des patients en continu et permet une grande amélioration dans les services médicaux. D'autre part, des Véhicules Ad-hoc NETwork (VANET) est une technologie émergente qui permet une communication intelligente entre les véhicules mobiles. Intégrer VANET avec USN a un grand potentiel pour améliorer la sécurité routière et la fluidité du trafic. La plupart des applications VANET sont appliqués en temps réel et ils sont sensibles à retarder, en particulier ceux liés à la sécurité et à la santé. Dans ce travail, nous proposons d'utiliser l'IP Multimédia Subsystem (IMS) comme une sous- couche de contrôle de service dans l'environnement USN fournir un substrat mondiale pour un service complet de bout en bout. De plus, nous vous proposons d'intégrer VANETs avec USN pour des applications et des installations riches plus, ce qui facilitera la vie des humains. Nous avons commencé à étudier les défis sur la route pour atteindre cet objectif
Ubiquités Sensor Network (USN) is a conceptual network built over existing physical networks. It makes use of sensed data and provides knowledge services to anyone, anywhere and at anytime, and where the information is generated by using context awareness. Smart wearable devices and USNs are emerging rapidly providing many reliable services facilitating people life. Those very useful small end terminals and devices require a global communication substrate to provide a comprehensive global end user service. In 2010, the ITU-T provided the requirements to support USN applications and services in the Next Génération Network (NGN) environment to exploit the advantages of the core network. One of the main promising markets for the USN application and services is the e-Health. It provides continuous patients’ monitoring and enables a great improvement in medical services. On the other hand, Vehicular Ad-Hoc NETwork (VANET) is an emerging technology, which provides intelligent communication between mobile vehicles. Integrating VANET with USN has a great potential to improve road safety and traffic efficiency. Most VANET applications are applied in real time and they are sensitive to delay, especially those related to safety and health. In this work, we propose to use IP Multimedia Subsystem (IMS) as a service controller sub-layer in the USN environment providing a global substrate for a comprehensive end-to-end service. Moreover, we propose to integrate VANETs with USN for more rich applications and facilities, which will ease the life of humans. We started studying the challenges on the road to achieve this goal

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Chung, W. Y. (Wan-Young). "Ubiquitous healthcare system based on a wireless sensor network". Doctoral thesis, University of Oulu, 2009. http://urn.fi/urn:isbn:9789514292903.

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Abstract This dissertation aimed at developing a multi-modal sensing u-healthcare system (MSUS), which reflects the unique properties of a healthcare application in a wireless sensor network. Together with health parameters, such as ECG, SpO2 and blood pressure, the system also transfers context-aware data, including activity, position and tracking data, in a wireless sensor network environment at home or in a hospital. Since packet loss may have fatal consequences for patients, health-related data are more critical than most other types of monitoring data. Thus, compared to environmental, agricultural or industrial monitoring, healthcare monitoring in a wireless environment imposes different requirements and priorities. These include heavy data traffic with wavelike parameters in wireless sensor network and fatal data loss due to the traffic. To ensure reliable data transfer in a wireless sensor network, this research placed special emphasis on the optimization of sampling rate, packet length and transmission rate, and on the traffic reduction method. To improve the reliability and accuracy of diagnosis, the u-healthcare system also collects context-aware information on the user’s activity and location and provides real-time tracking. Waveform health parameters, such as ECG, are normally sampled in the 100 to 400 Hz range according to the monitoring purpose. This type of waveform data may incur a heavy burden in wireless communication. To reduce wireless traffic between the sensor nodes and the gateway node, the system utilizes on-site ECG analysis implemented on the sensor nodes as well as query architecture. A 3D VRML viewer was also developed for the realistic monitoring of the user’s moving path and location. Two communication methods, an 802.15.4-based wireless sensor network and a CDMA cellular network are used by sensors placed on the users’ bodies to gather medical data, which is then transmitted to a server PC at home or in the hospital, depending on whether the sensor is within or outside the range of the wireless sensor network.

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Lipshin, Jason Martin. "Network design : a theory of scale for ubiquitous computing". Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/89972.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Comparative Media Studies, 2014.
"June 2014." Cataloged from PDF version of thesis.
Includes bibliographical references (pages 126-141).
Ubiquitous computing (aka "ubicomp") describes the process of embedding computation into everyday things. From smart toasters and smart shoes to smart toys and smart buildings, ubicomp describes user experiences which are both big and small and which operate at a wide variety of scales and gradations in between. However, existing research in new media studies and human computer interaction does not adequately address this question of scale in relation to ubiquitous computing. In this thesis, I propose a more robust theoretical framework I call "network design." It argues that differently scaled ubicomp systems have their own potentials and challenges, histories and precedents, material affordances and ethical implications. This thesis identifies and analyzes the operation of ubiquitous computing networks at three scales: the body scale, the architectural scale and the urban scale. The case studies for each chapter, respectively, include: exercise wristwatches and quantified self literature, responsive environments like smart homes and smart offices, and smart city initiatives dealing with sensors placed in urban infrastructure. In each scale, I identify common characteristics of that scale, historical precedents, as well what happens when this particular kind of network "scales up" or "scales down." Thus, although I am interested in describing the unique characteristics of differently scaled ubicomp networks, I am also interested in describing situations when scales interact.
by Jason Martin Lipshin.
S.M.

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Clark, R. J. (Russell J. ). "Solutions for ubiquitous information services : multiple protocols and scalable servers". Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/8489.

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Ma, Junkang. "Ubiquitous communications for wireless personal area networks in a heterogeneous environment". Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/6497.

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The widespread use of wireless technologies has led to a tremendous development in wireless communication systems. Currently, an individual mobile user may carry multiple personal devices with multiple wireless interfaces, which can interconnect with each other to form a Wireless Personal Area Network (WPAN) which moves with this user. These devices exist in a heterogeneous environment which is composed of various wireless networks with differing coverage and access technologies and also the topology, device conditions and wireless connections in the WPAN may be dynamically changing. Such individual mobile users require ubiquitous communications anytime, anywhere, with any device and wish content to be efficiently and continuously transferred across the various wireless networks both outside and inside WPANs, wherever they move. This thesis presents research carried out into how to implement ubiquitous communications for WPANs in such an environment. Two main issues are considered. The first is how to initiate content transfer and keep it continuous, no matter which wireless network is used as a user moves or how the WPAN changes dynamically. The second is how to implement this transfer in the most efficient way: selecting the most suitable transfer mode for a WPAN according to the user’s and application’s requirements. User-centric (personal-area-centric) and contentcentric mechanisms are proposed in this thesis to address these issues. A scheme based on a Personal Distributed Environment (PDE) concept and designed as a logical user-based management entity is presented. This is based on three mechanisms which are proposed to overcome the technical problems in practical scenarios, which cannot be solved by existing approaches. A novel mechanism is proposed to combine local direct and global mobile communications, in order to implement ubiquitous communications in both infrastructure-less and infrastructurebased networks. This enables an individual user’s ubiquitous communications to be initiated in an infrastructure-less network environment and kept continuous when they move across infrastructure-based networks. Its advantages are evaluated by a performance analysis model and compared to existing solutions and verified by experiments. A cooperation and management scheme is also proposed for dynamic changes of multiple mobile routers and flexible switching of personal device roles in a WPAN while keeping ongoing ubiquitous communications continuous. This adopts a novel view of WPANs which solves the addressing problems caused by changes of mobile routers and makes these transparent to personal devices in the WPAN and external content sources. It provides an efficient method for changing the mobile router of a single WPAN or a WPAN merging with another moving network. Its benefits are demonstrated through performance analysis models. Finally, a novel user-centric and contentcentric mechanism for decision making, to select the most appropriate mobile router in a dynamically changing WPAN environment is proposed. This selects the most suitable content transfer mode for the WPAN to fulfil an individual user’s various requirements. It has different strategies to suit various types of applications. Selection results are demonstrated to verify the proposed mechanism in multiple scenarios of changing user requirements, applications and WPAN conditions.

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Chen, Weisong. "A pervasive information framework based on semantic routing and cooperative caching". Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31065326.

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Chen, Weisong, i 陳偉松. "A pervasive information framework based on semantic routing and cooperative caching". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31065326.

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Prakash, Abhinav. "Rendering Secured Connectivity in a Wireless IoT Mesh Network with WPAN's and VANET's". University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1491557510577536.

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Wullems, Christian John. "Engineering Trusted Location Services and Context-aware Augmentations for Network Authorization Models". Thesis, Queensland University of Technology, 2005. https://eprints.qut.edu.au/16707/1/Christian_Wullems_Thesis.pdf.

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Context-aware computing has been a rapidly growing research area, however its uses have been predominantly targeted at pervasive applications for smart spaces such as smart homes and workplaces. This research has investigated the use of location and other context data in access control policy, with the purpose of augmenting existing IP and application-layer security to provide fine-grained access control and effective enforcement of security policy. The use of location and other context data for security purposes requires that the technologies and methods used for acquiring the context data are trusted. This thesis begins with the description of a framework for the analysis of location systems for use in security services and critical infrastructure. This analysis classifies cooperative locations systems by their modes of operation and the common primitives they are composed of. Common location systems are analyzed for inherent security flaws and limitations based on the vulnerability assessment of location system primitives and the taxonomy of known attacks. An efficient scheme for supporting trusted differential GPS corrections is proposed, such that DGPS vulnerabilities that have been identified are mitigated. The proposal augments the existing broadcast messaging protocol with a number of new messages facilitating origin authentication and integrity of broadcast corrections for marine vessels. A proposal for a trusted location system based on GSM is presented, in which a model for tamper resistant location determination using GSM signaling is designed. A protocol for association of a user to a cell phone is proposed and demonstrated in a framework for both Web and Wireless Application Protocol (WAP) applications. After introducing the security issues of existing location systems and a trusted location system proposal, the focus of the thesis changes to the use of location data in authorization and access control processes. This is considered at both the IP-layer and the application-layer. For IP-layer security, a proposal for location proximity-based network packet filtering in IEEE 802.11 Wireless LANs is presented. This proposal details an architecture that extends the Linux netfilter system to support proximity-based packet filtering, using methods of transparent location determination through the application of a pathloss model to raw signal measurements. Our investigation of application-layer security resulted in the establishment of a set of requirements for the use of contextual information in application level authorization. Existing network authentication protocols and access control mechanisms are analyzed for their ability to fulfill these requirements and their suitability in facilitating context-aware authorization. The result is the design and development of a new context-aware authorization architecture, using the proposed modifications to Role-based Access Control (RBAC). One of the distinguishing characteristics of the proposed architecture is its ability to handle authorization with context-transparency, and provide support for real-time granting and revocation of permissions. During the investigation of the context-aware authorization architecture, other security contexts in addition to host location were found to be useful in application level authorization. These included network topology between the host and application server, the security of the host and the host execution environment. Details of the prototype implementation, performance results, and context acquisition services are presented.

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Wullems, Christian John. "Engineering Trusted Location Services and Context-aware Augmentations for Network Authorization Models". Queensland University of Technology, 2005. http://eprints.qut.edu.au/16707/.

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Context-aware computing has been a rapidly growing research area, however its uses have been predominantly targeted at pervasive applications for smart spaces such as smart homes and workplaces. This research has investigated the use of location and other context data in access control policy, with the purpose of augmenting existing IP and application-layer security to provide fine-grained access control and effective enforcement of security policy. The use of location and other context data for security purposes requires that the technologies and methods used for acquiring the context data are trusted. This thesis begins with the description of a framework for the analysis of location systems for use in security services and critical infrastructure. This analysis classifies cooperative locations systems by their modes of operation and the common primitives they are composed of. Common location systems are analyzed for inherent security flaws and limitations based on the vulnerability assessment of location system primitives and the taxonomy of known attacks. An efficient scheme for supporting trusted differential GPS corrections is proposed, such that DGPS vulnerabilities that have been identified are mitigated. The proposal augments the existing broadcast messaging protocol with a number of new messages facilitating origin authentication and integrity of broadcast corrections for marine vessels. A proposal for a trusted location system based on GSM is presented, in which a model for tamper resistant location determination using GSM signaling is designed. A protocol for association of a user to a cell phone is proposed and demonstrated in a framework for both Web and Wireless Application Protocol (WAP) applications. After introducing the security issues of existing location systems and a trusted location system proposal, the focus of the thesis changes to the use of location data in authorization and access control processes. This is considered at both the IP-layer and the application-layer. For IP-layer security, a proposal for location proximity-based network packet filtering in IEEE 802.11 Wireless LANs is presented. This proposal details an architecture that extends the Linux netfilter system to support proximity-based packet filtering, using methods of transparent location determination through the application of a pathloss model to raw signal measurements. Our investigation of application-layer security resulted in the establishment of a set of requirements for the use of contextual information in application level authorization. Existing network authentication protocols and access control mechanisms are analyzed for their ability to fulfill these requirements and their suitability in facilitating context-aware authorization. The result is the design and development of a new context-aware authorization architecture, using the proposed modifications to Role-based Access Control (RBAC). One of the distinguishing characteristics of the proposed architecture is its ability to handle authorization with context-transparency, and provide support for real-time granting and revocation of permissions. During the investigation of the context-aware authorization architecture, other security contexts in addition to host location were found to be useful in application level authorization. These included network topology between the host and application server, the security of the host and the host execution environment. Details of the prototype implementation, performance results, and context acquisition services are presented.

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Mannapperuma, Chanaka. "Tangible Social Network System : Visual Markers for Social Network". Thesis, Umeå University, Department of Informatics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34927.

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Tangible social network system is a home-based communication solution specifically designed for elders. Former researches indicate that insufficient communication among elders cause several challenges in their daily activities such as social isolation, loneliness, depression and decreased appetite. In addition, lack of social participation increases the risk of Alzheimer´s (Ligt Enid, 1990). The major cause of these challenges are that elders are increasingly removed from communication technology using emails, text messaging, interact with social network systems and mobile phones due to cognitive and physical difficulties. To overcome this problem, new suggested social network system incorporates photo frame and photo album based interaction which allows instantaneous participation to the social network. By designing the new social network system, I tried to create an easier venue for more active cross-generational communication between elders and younger family members.This paper discusses the early results of the marker based social networking system aiming to propose digital technologies to enhance the social life of older people, who live alone their home. A prototype combining a touch screen, photo frame and a camera are described. It allows the older people to manage their participation to the social network system and get in touch with their loved ones. This paper demonstrates a User Sensitive inclusive Design (USID) process from the generation of user needs to the evaluation prototype. A key theme of tangible social network system shows how usable and emotional design derived from a user inclusive design process can encourage elders to adopt new modern technology. A first evaluation has shown the usability as well as the good acceptance of this system.

AGNES

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Vasanta, Harikrishna. "Secure, privacy assured mechanisms for heterogeneous contextual environments". Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16177/1/Harikrishna_Vasanta_Thesis.pdf.

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Location information is used to provide a diverse range of services to users such as emergency, navigation, billing, security, information and advertising services. This information is derived from a broad range of indoor and outdoor technologies. The location information thus derived is of different granularity, different co-ordination system and is controlled by numerous service providers. In addition to this, broad selections of devices are used for providing these services. Having a diverse range of applications requiring location information at different levels of granularity, the need to export location information across multiple devices and the existence of different location determination technologies necessitates the need for heterogeneous location network. These networks derive location information from multiple sources and provides various location-based services to users irrespective of the medium, device or technology used. Security, user privacy and management of location information are some of the important issues that need to be addressed. The main contribution of this thesis is the design of a secure and privacy assured heterogeneous location architecture. A formal methodology was chosen to design the heterogeneous location architecture. The design of the architecture resulted in a novel key distribution protocol and a model for information flow that can be easily encapsulated into applications or architectures having similar requirements. The research also resulted in the enhancement of a proposed location framework for securing critical infrastructures using context-aware self-defending objects. The proposed enhanced framework helps to negate the security vulnerabilities introduced through the use of general-purpose computer systems in critical infrastructures.

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Vasanta, Harikrishna. "Secure, privacy assured mechanisms for heterogeneous contextual environments". Queensland University of Technology, 2006. http://eprints.qut.edu.au/16177/.

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Location information is used to provide a diverse range of services to users such as emergency, navigation, billing, security, information and advertising services. This information is derived from a broad range of indoor and outdoor technologies. The location information thus derived is of different granularity, different co-ordination system and is controlled by numerous service providers. In addition to this, broad selections of devices are used for providing these services. Having a diverse range of applications requiring location information at different levels of granularity, the need to export location information across multiple devices and the existence of different location determination technologies necessitates the need for heterogeneous location network. These networks derive location information from multiple sources and provides various location-based services to users irrespective of the medium, device or technology used. Security, user privacy and management of location information are some of the important issues that need to be addressed. The main contribution of this thesis is the design of a secure and privacy assured heterogeneous location architecture. A formal methodology was chosen to design the heterogeneous location architecture. The design of the architecture resulted in a novel key distribution protocol and a model for information flow that can be easily encapsulated into applications or architectures having similar requirements. The research also resulted in the enhancement of a proposed location framework for securing critical infrastructures using context-aware self-defending objects. The proposed enhanced framework helps to negate the security vulnerabilities introduced through the use of general-purpose computer systems in critical infrastructures.

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Huhtinen, J. (Jouni). "Utilization of neural network and agent technology combination for distributed intelligent applications and services". Doctoral thesis, University of Oulu, 2005. http://urn.fi/urn:isbn:9514278550.

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Abstract The use of agent systems has increased enormously, especially in the field of mobile services. Intelligent services have also increased rapidly in the web. In this thesis, the utilization of software agent technology in mobile services and decentralized intelligent services in the multimedia business is introduced and described. Both Genie Agent Architecture (GAA) and Decentralized International and Intelligent Software Architecture (DIISA) are described. The common problems in decentralized software systems are lack of intelligence, communication of software modules and system learning. Another problem is the personalization of users and services. A third problem is the matching of users and service characteristics in web application level in a non-linear way. In this case it means that web services follow human steps and are capable of learning from human inputs and their characteristics in an intelligent way. This third problem is addressed in this thesis and solutions are presented with two intelligent software architectures and services. The solutions of the thesis are based on a combination of neural network and agent technology. To be more specific, solutions are based on an intelligent agent which uses certain black box information like Self-Organized Map (SOM). This process is as follows; information agents collect information from different sources like the web, databases, users, other software agents and the environment. Information is filtered and adapted for input vectors. Maps are created from a data entry of an SOM. Using maps is very simple, input forms are completed by users (automatically or manually) or user agents. Input vectors are formed again and sent to a certain map. The map gives several outputs which are passed through specific algorithms. This information is passed to an intelligent agent. The needs for web intelligence and knowledge representation serving users is a current issue in many business solutions. The main goal is to enable this by means of autonomous agents which communicate with each other using an agent communication language and with users using their native languages via several communication channels.

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Kim, Kibum. "The Effects of Handheld Network Service "Look" on the Acquisition of Common Ground". Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/26047.

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Constructing common ground and the associated convergent conceptual change is critical to cooperative work and learning. Convergent conceptual change is achieved as participants in a conversation update common ground through presentations, repairs, and acceptances of utterances. People employ available techniques that utilize the least collaborative effort for current purposes. Although sharing physical co-presence of interlocutors' facial expressions doesn't make grounding more efficient even in more open-ended and less task-focused dialogues, visual co-presence of the addressee's workspace is essential to work-related tasks, such as information transmission and collaborative problem-solving. However, handheld-mediated collaborative activity makes sharing the workspace challenging, especially when we consider that handhelds possess small screens and permit activities of a distributed nature. In a handheld-mediated classroom, a teacher must be able to check students' work for various reasons (e.g., grading, checking whether they are following directions correctly or paying attention) and at various phases of the activity. Gazing into the small screen of a handheld over someone's shoulder is a tricky task at best. The teacher may misread the information on the screen and thus provide incorrect feedback. Another challenge involves the difficulty inherent in latecomers joining the collaborative activity when each student is involved with his or her individual and small screen. This exclusion from joining on-going activity can reduce the chance of student's vicarious and serendipitous learning. Although such events may occur naturally in the learning environment, they become important concerns when one attempts to focus collaborative activities with handheld devices. I therefore created a new handheld network service called "Look," which is designed to facilitate the acquisition of common ground and allow a latecomer to do meaningful monitoring of ongoing conversation about the workspace. I tested empirically the value of this shared physical/virtual context in the task of creating common ground by examining task performance and conversation quality.
Ph. D.

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Åkesson, Maria. "Digital Innovation in the Value Networks of Newspapers". Doctoral thesis, Högskolan i Halmstad, Halmstad Embedded and Intelligent Systems Research (EIS), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-14056.

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After decades of digital developments, we are now entering a truly digital era. Digital information and communication technology has become a naturally embedded part ofthe designed environment we live in. Most parts of life are today pervaded by digital products and services. Evidence of such immersion can be noted in, for instance, media consumption. This development is gradually shaping and cultivating a media environment that is ubiquitous. Such ubiquity is manifested in media’s constant presence and thechanges in media consumption in the purview of digital innovation. Indeed, digital innovation is not only a shift in technology. It alters existing value networks and calls forrethinking existing value perceptions. While this disruptive change driven by digitizationcan be found in many industries, this thesis focuses on its impact on value networks in thenewspaper industry.The digitization of newspapers started with the introduction of the internet in the 90´sand soon emerged into new media innovations. While these new media innovations have not replaced existing media, they have been disruptive to newspaper value networks. Recently, the emergence of yet another digital innovation is specifically interesting whenstudying changes to value networks of the newspaper industry: the e-paper. This innovation (a screen technology very close to print on paper) exhibits inherent valuesthat make future replacement of print on paper a possibility. It is therefore regarded as avery promising technology in the newspaper industry. This thesis can be positioned at the intersection of the friction between forces to embarkon a new media trajectory and forces to hang on to the established structures andcontrol. The research question addressed in this thesis is: How are value networks of newspapers influenced by digital innovation? Addressing the research question, a multimethod approach was adopted to gain a broad understanding of how digital innovationinfluences value networks of newspapers. Drawing on digital innovation literature, the thesis presents a theoretical perspective with which to understand how digital innovation influences value networks. This perspective is instantiated as a model of value network configuration. The model emphasizes the multi-layered, dynamic, dialectic, and diametrical character of value networks in digital innovation. The model is offered as abasis and analytical tool to further explore value networks in digital innovation. This tool is useful for newspaper stakeholders when entering the digital era.

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Navarro, Natália de Arruda Botelho. "Spontaneous social network: creating dynamic virtual communities based on context-aware computing". Universidade do Vale do Rio dos Sinos, 2016. http://www.repositorio.jesuita.org.br/handle/UNISINOS/5229.

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Santander Universidades
Com a emergência de redes sociais junto à difusão mundial de smartphones, ciência de contexto tornou-se um conceito essencial na área da computação móvel. Esforços recentes e pesquisas relevantes sobre redes sociais móveis visam conectar pessoas em ambientes inteligentes, considerando não apenas seu comportamento social, mas também seu contexto. Neste âmbito, este trabalho apresenta um novo modelo de rede social móvel, chamado rede social espontânea. A principal contribuição do modelo de rede social espontânea é possibilitar a criação de comunidades sociais baseadas na combinação de múltiplos contextos, incluindo localização, perfil e dados obtidos de outras redes sociais. Na literatura, encontramos alguns trabalhos que carecem na abordagem de formação de comunidades, no aspecto da limitação a localizações específicas ou em não suportar completamente interações sociais virtuais. Nós desenvolvemos um aplicativo móvel chamado Dino, para proporcionar uma visão do que seria uma aplicação baseada no modelo de rede social espontânea. Para avaliar nosso modelo, realizamos dois experimentos. Primeiro, apresentamos cenários hipotéticos baseados em possíveis aplicações para mensurar a percepção dos usuários quanto ao senso de comunidade. Os cenários descritos foram (1) evento musical (2) evento esportivo (3) shopping center (4) conferência ou workshop (5) escola ou universidade. Em sequência, pedimos que os usuários avaliassem as sugestões de grupos formados pela aplicação, considerando sua relevância em meio aos seus interesses. Então, medimos precisão e recuperação dos grupos sugeridos para cada usuário. Obtemos valores médios de 0.72 e 0.83 para precisão e recuperação, respectivamente. Como resultado dos experimentos para avaliar os cenários propostos, obtemos valores médios de concordância de 84% para senso de comunidade, 80% para senso de pertencimento, 90% para utilidade social, 92% para fidelidade de participação, e 81% para efemeridade das comunidades. Com isso, nossa avaliação retrata que comunidades dinâmicas formadas por uma aplicação baseada no modelo de redes sociais espontâneas poderiam aumentar beneficamente a utilidade de um ambiente virtual social.
With the emerging of online social networks along with the worldwide diffusion of smartphones, context awareness has become an essential concept in the field of mobile computing. Recent efforts and relevant research regarding mobile social networks aim at connecting people in smart environments considering not only their social behavior but also their context. In this perspective, this work presents a novel Mobile Social Network (MSN) model called Spontaneous Social Network (SSN). The main scientific contribution of the SSN model is the possibility of creating social communities based on a combination of multiple contexts, including location, profile and data obtained from external online social networks. In the literature, we found several works that lack on the community grouping approach, on the aspect that they are either limited to a specific location, or do not fully support virtual social interactions. We develop a mobile application called Dino, to provide a glimpse of what an SSN based application would be. To evaluate our model we perform two experiments using the developed mobile client. First, we present hypothetical scenarios based on possible real-world SSN applications to measure users’ perceived sense of community. The scenarios described are (1) music concert (2) sport event (3) shopping mall (4) conference or workshop (5) school or university. Second, we ask users to consider their real interests to assess our formed groups regarding their relevance and measure precision and recall of the groups’ suggestions. We compute average values of 0.72 and 0.83 for precision and recall, respectively. The experiments’ results to assess the proposed scenarios ascertain average values of agreement of 84% for sense of community, 80% for sense of belonging, 90% for social usefulness, 92% for member loyalty, and 81% for communities’ ephemerality. Therefore, our evaluation depict that dynamic virtual communities formed by a SSN model based application would beneficially improve a social-aware virtual environment.

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Ventä-Olkkonen, L. (Leena). "The characteristics and development of urban computing practices:utilizing practice toolkit approach to study public display network". Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526217338.

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Abstract This thesis concentrates on understanding people’s daily interactions with urban technologies and the role they play in everyday life by investigating use practices for the on urban, multipurpose, public display network in the city of Oulu in northern Finland. The goal is two-fold, namely, to investigate different aspects of emerging urban computing practices and understand the versatility of the contributing factors behind these practices. The work is grounded in practice theory that understands practices as a result of an historical evolution influenced by several forces. On the one hand, the thesis concentrates on the local accomplishment of practices; on the other hand it, seeks to understand the broader connections between these practices as well as their history and evolution. The material comes from three main sources: Users of the public displays, their developers and additional stakeholders involved in the design process, and citizen comments on the display network project on social media. The research is based on empirical qualitative research material; quantitative use statistics are applied to support the findings. The findings reveal that urban computing practices take on influences from several directions including designers and other stakeholders during the design phase, the users’ lives and existing practices, and ongoing societal and communal discourses. The thesis offers increased understanding of the designing and implementation of successful ubiquitous computing projects in a public setting
Tiivistelmä Tämä väitöskirja keskittyy ymmärtämään ihmisten päivittäistä vuorovaikutusta kaupunkiteknolgian kanssa tutkimalla käytäntöjä julkisten näyttöjen verkoston ympärillä. Tavoite on toisaalta tutkia kaupunkiteknologiakäytänteitä eri näkökulmista ja toisaalta ymmärtää monipuolisia osatekijöitä käytäntöjen takana. Työ perustuu käytäntöteoriaan, joka ymmärtää käytäntöjä historiallisen kehityksen seurauksena sekä usean osatekijän tuloksena. Toisaalta tutkielma keskittyy paikallisiin käytäntöihin; toisaalta se yrittää ymmärtää laajempia yhteyksiä käytäntöjen välillä sekä niiden historiaa ja evoluutiota. Materiaali tulee kolmesta päälähteestä: 1) Julkisten näyttöjen verkoston kehittäjiltä ja muilta suunnitteluprosessin sidosryhmiltä, 2) näyttöjen käyttäjiltä sekä 3) kaupunkilaisilta, jotka kommentoivat näyttöverkkoprojektia sosiaalisessa mediassa. Tutkimus perustuu laadulliseen tutkimusaineistoon, jonka lisäksi määrällistä käyttötilastoaineistoa sovelletaan tukemaan laadullisia havaintoja. Havainnot paljastavat, että urbaanin teknologian käytänteisiin vaikuttavat monet tekijät mukaan lukien suunnittelijat ja muut suunnitteluvaiheen sidosryhmät, käyttäjien elämä ja heidän olemassa olevat käytänteensä sekä ajankohtainen yhteiskunnallinen ja yhteisöllinen keskustelu. Tutkielma tarjoaa uudenlaista ymmärrystä jokapaikan tietotekniikka -projektien suunnittelusta ja toteutuksesta julkisissa ympäristöissä

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La, Rosa Giovanni. "Prototipazione di un Modello di Trust in una rete di sensori". Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

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La recente esplosione di tecnologie quali Pervasive Computing e IoT ha fatto sı̀ che, negli ultimi anni, da una parte facessero ingresso nelle nostre vite dispositivi in grado di interagire con l’ambiente circostante grazie ai sensori di cui sono dotati che permettono di eseguire continue rilevazioni di numerosi tipi di dati, dall’altra che molti oggetti, anche di uso comune, venissero dotati di tecnologie di comunicazione e che divenissero capaci di comunicare in internet. Questo, oltre a portare molteplici benefici in numerosi campi di applicazione, ha generato un forte interesse dal punto di vista commerciale e numerosi produttori in tutto il mondo si sono lanciati in questo mercato. Non esistendo un criterio di comunicazione condiviso da tutti, questo ha determinato che dal punto di vista tecnologico la situazione si andasse cosı̀ a frammentare. L’obiettivo di questo studio è di illustrare come l’integrazione di un modello di trust possa fornire una valida soluzione al problema dell’eterogeneità e alla bassa qualità dei dati rilevati dovuta al basso costo dei dispositivi coinvolti. Contestualmente apporta numerosi benefici all’efficenza del sistema in termine di ottimizzazione delle risorse e di attuazione di strategie di identificazione degli errori.

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20

Nassar, Jad. "Ubiquitous networks for Smart Grids". Thesis, Lille 1, 2018. http://www.theses.fr/2018LIL1I053/document.

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Les Smart Grids visent à transformer le réseau électrique actuel en un réseau "plus intelligent" où la production énergétique est décentralisée et automatisée, facilitant l'intégration des sources d'énergie renouvelables. Cette évolution est rendue possible grâce à l'utilisation d'un réseau de communication pour les multiples échanges de données hétérogènes des Smart Grids. L'objectif de cette thèse est de proposer un paradigme de communication efficace en termes de qualité de service pour les Smart Grids basé sur les réseaux de capteurs.Dans un premier temps, on s’intéresse au protocole standard RPL. Nous proposons une évolution de celui-ci à travers une nouvelle fonction objectif. Celle-ci tire parti de l’hétérogénéité matérielle des nœuds et des liens pour introduire la qualité de service. Cela permet à RPL de satisfaire les multiples et différentes exigences en termes de fiabilité, de latence et de priorité dans l'acheminement des données. Nos résultats montrent que notre approche permet bien la différentiation du trafic tout en réduisant la latence du routage et en économisant l'énergie.Nous proposons également d'améliorer l'utilisation du réseau de capteurs en y introduisant l’auto-organisation et la réduction des données. Le but est alors de prédire la valeur des données mesurées plutôt que de les transmettre.Une autre approche explorée est d'agréger les différents messages transitant sur le réseau tout en considérant leurs différentes exigences de qualité de service. Ces deux approches permettent ainsi de réduire la consommation d'énergie tout en respectant les exigences des différentes applications des Smart Grids
Smart Grids aim to transform the current electric grid into a "smarter" network where energy production is decentralized and automated, which facilitates the integration of renewable energy resources. This evolution is made possible thanks to the use of a communication network for the multiple heterogeneous data exchanges of the Smart Grids. Hence, the aim of this thesis is to propose an efficient communication paradigm in terms of quality of service for Smart Grids based on wireless sensor networks.First, we study data routing in Smart Grids with the RPL standard. Nevertheless, RPL is not suitable for Smart Grid applications in terms of quality of service. Therefore, we propose an objective function for RPL that takes different features of both nodes and links into consideration. Results show that our approach improves network performance compared to existing solutions in terms of packet delivery ratio, network lifetime, latency and traffic differentiation.Then, we also propose a more efficient data collection by introducing self-organization and data reduction for these wireless sensors. The goal is to predict the value of the measured data rather than transmitting them. Another explored approach is to aggregate the different messages sent across the network while considering their different requirements in terms of quality of service.These two approaches reduce the energy consumption while respecting the requirements of the different applications of the Smart Grids

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Dalton, Benjamin Christopher. "Audio-based localisation for ubiquitous sensor networks". Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/34103.

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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2005.
Includes bibliographical references (p. 97-101).
This research presents novel techniques for acoustic-source location for both actively triggered, and passively detected signals using pervasive, distributed networks of devices, and investigates the combination of existing resources available in personal electronics to build a digital sensing 'commons'. By connecting personal resources with those of the people nearby, tasks can be achieved, through distributed placement and statistical improvement, that a single device could not do alone. The utility and benefits of spatio-temporal acoustic sensing are presented, in the context of ubiquitous computing and machine listening history. An active audio self-localisation algorithm is described which is effective in distributed sensor networks even if only coarse temporal synchronisation can be established. Pseudo-noise 'chirps' are emitted and recorded at each of the nodes. Pair-wise distances are calculated by comparing the difference in the audio delays between the peaks measured in each recording. By removing dependence on fine grained temporal synchronisation it is hoped that this technique can be used concurrently across a wide range of devices to better leverage the existing audio sensing resources that surround us.
(cont.) A passive acoustic source location estimation method is then derived which is suited to the microphone resources of network-connected heterogeneous devices containing asynchronous processors and uncalibrated sensors. Under these constraints position coordinates must be simultaneously determined for pairs of sounds and recorded at each microphone to form a chain of acoustic events. It is shown that an iterative, numerical least-squares estimator can be used. Initial position estimates of the source pair can be first found from the previous estimate in the chain and a closed-form least squares approach, improving the convergence rate of the second step. Implementations of these methods using the Smart Architectural Surfaces development platform are described and assessed. The viability of the active ranging technique is further demonstrated in a mixed-device ad-hoc sensor network case using existing off-the-shelf technology. Finally, drawing on human-centric onset detection as a means of discovering suitable sound features, to be passed between nodes for comparison, the extension of the source location algorithm beyond the use of pseudo-noise test sounds to enable the location of extraneous noises and acoustic streams is discussed for further study.
Benjamin Christopher Dalton.
S.M.

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22

Jaimes, Luis Gabriel. "A Location-Based Incentive Mechanism for Participatory Sensing Systems with Budget Constraints". Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4087.

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Participatory Sensing (PS) systems rely on the willingness of mobile users to participate in the collection and reporting of data using a variety of sensors either embedded or integrated in their cellular phones. Users agree to use their cellular phone resources to sense and transmit the data of interest because these data will be used to address a collective problem that otherwise would be very difficult to assess and solve. However, this new data collection paradigm has not been very successful yet mainly because of the lack of incentives for participation and privacy concerns. Without adequate incentive and privacy guaranteeing mechanisms most users will not be willing to participate. This thesis concentrates on incentive mechanisms for user participation in PS system. Although several schemes have been proposed thus far, none has used location information and imposed budget and coverage constraints, which will make the scheme more realistic and efficient. A recurrent reverse auction incentive mechanism with a greedy algorithm that selects a representative subset of the users according to their location given a fixed budget is proposed. Compared to existing mechanisms, GIA (i.e., Greedy Incentive Algorithm) improves the area covered by more than 60 percent acquiring a more representative set of samples after every round, i.e., reduces the collection of unnecessary (redundant) data, while maintaining the same number of active users in the system and spending the same budget.

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Perez, Alfredo Jose. "An Architecture for Global Ubiquitous Sensing". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3276.

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A new class of wireless sensor networks has recently appeared due to the pervasiness of cellular phones with embedded sensors, mobile Internet connectivity, and location technologies. This mobile wireless sensor network has the potential to address large-scale societal problems and improve the people's quality of life in a better, faster and less expensive fashion than current solutions based on static wireless sensor networks. Ubiquitous Sensing is the umbrella term used in this dissertation that encompasses location-based services, human-centric, and participatory sensing applications. At the same time, ubiquitous sensing applications are bringing a new series of challenging problems. This dissertation proposes and evaluates G-Sense, for Global-Sense, an architecture that integrates mobile and static wireless sensor networks, and addresses several new problems related to location-based services, participatory sensing, and human-centric sensing applications. G-Sense features the critical point algorithms, which are specific mechanisms to reduce the power consumption by continous sensing applications in cellular phones, and reduce the amount of data generated by these applications. As ubiquitous sensing applications have the potential to gather data from many users around the globe, G-Sense introduces a peer-to-peer system to interconnect sensing servers based on the locality of the data. Finally, this dissertation proposes and evaluates a multiobjective model and a hybrid evolutionary algorithm to address the efficient deployment of static wireless sensor nodes when monitoring critical areas of interest.

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Rashid, Md Jayedur. "Extending a networked robot system to include humans, tiny devices, and everyday objects". Doctoral thesis, Örebro universitet, Akademin för naturvetenskap och teknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-15247.

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In networked robot systems (NRS), robots and robotic devices are distributed in the environment; typically tasks are performed by cooperation and coordination of such multiple networked components. NRS offer advantages over monolithic systems in terms of modularity, flexibility and cost effectiveness, and they are thus becoming a mainstream approach to the inclusion of robotic solutions in everyday environments. The components of a NRS are usually robots and sensors equipped with rich computational and communication facilities. In this thesis, we argue that the capabilities of a NRS would greatly increase if it could also accommodate among its nodes simpler entities, like small ubiquitous sensing and actuation devices, home appliances, or augmented everyday objects. For instance, a domestic robot needs to manipulate food items and interact with appliances. Such a robot would benefit from the ability to exchange information with those items and appliances in a direct way, in the same way as with other networked robots and sensors. Combining such highly heterogeneous devices inside one NRS is challenging, and one of the major challenges is to provide a common communication and collaboration infrastructure. In the field of NRS, this infrastructure is commonly provided by a shared middleware. Unfortunately, current middlewares lack the generality needed to allow heterogeneous entities such as robots, simple ubiquitous devices and everyday objects to coexist in the same system. In this thesis we show how an existing middleware for NRS can be extended to include three new types of “citizens” in the system, on peer with the other robots. First, we include computationally simple embedded devices, like ubiquitous sensors and actuators, by creating a fully compatible tiny version of the existing robotic middleware. Second, we include augmented everyday objects or home appliances which are unable to run the middleware on board, by proposing a generic design pattern based on the notion of object proxy. Finally,we go one step further and include humans as nodes in the NRS by defining the notion of human proxy. While there exist a few other NRS which are able to include both robots and simple embedded devices in the same system, the use of proxies to include everyday objects and humans in a generic way is a unique feature of this work. In order to verify and validate the above concepts, we have implemented them in the Peis-Ecology NRS model. We report a number of experiments based on this implementation, which provide both quantitative and qualitative evaluations of its performance, reliability, and interoperability.

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25

Jiang, Bing. "Ubiquitous monitoring of distributed infrastructures /". Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/6118.

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26

Choi, Jaz Hee-jeong. "Playpolis : transyouth and urban networking in Seoul". Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/37610/1/Jaz_Choi_Thesis.pdf.

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The overarching aim of this study is to create new knowledge about how playful interactions (re)create the city via ubiquitous technologies, with an outlook to apply the knowledge for pragmatic innovations in relevant fields such as urban planning and technology development in the future. The study looks at the case of transyouth, the in-between demographic bridging youth and adulthood in Seoul, one of the most connected, densely populated, and quickly transforming metropolises in the world. To unravel the elusiveness of ‘play’ as a subject and the complexity of urban networks, this study takes a three-tier transdisciplinary approach comprised of an extensive literature review, Shared Visual Ethnography (SVE), and interviews with leading industry representatives who design and develop the playscape for Seoul transyouth. Through these methodological tools, the study responds to the following four research aims: 1. Examine the sociocultural, technological, and architectural context of Seoul 2. Investigate Seoul transyouth’s perception of the self and their technosocial environment 3. Identify the pattern of their playful interaction through which meanings of the self and the city are recreated 4. Develop an analytical framework for enactment of play This thesis argues that the city is a contested space that continuously changes through multiple interactions among its constituents on the seam of control and freedom. At the core of this interactive (re)creation process is play. Play is a phenomenon that is enacted at the centre of three inter-related elements of pressure, possibility, and pleasure, the analytical framework this thesis puts forward as a conceptual apparatus for studying play across disciplines. The thesis concludes by illustrating possible trajectories for pragmatic application of the framework for envisioning and building the creative, sustainable, and seductive city.

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27

Scherer, Drew P. "Urban Free Agents: Active Territories Through Nascent Ubiquitous Networks". University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1336682944.

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Gauger, Matthias. "Integration of wireless sensor networks in pervasive computing scenarios". Berlin Logos-Verl, 2010. http://d-nb.info/1002361559/04.

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Liu, Huanjin. "Free roaming: A system for ubiquitous computing". CSUSB ScholarWorks, 2006. https://scholarworks.lib.csusb.edu/etd-project/3062.

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Based on the Umbilical Cord system, this project enriches the Ubiquitous Computing system with a Free Roaming system. This Free Roaming consists of a distributed authentication system, a data caching system and a communication system between them. It allows user to roam within this system and access his data everywhere. Together with the Umbilical Cord system, a Ubiquitous Computing system is functionally completed as a prototype, and is ready to be deployed into the Internet.

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Santos, Marcelo da Silva dos. "INTERACT: um modelo baseado em contextos para motivação de interações em redes sociais". Universidade do Vale do Rio dos Sinos, 2017. http://www.repositorio.jesuita.org.br/handle/UNISINOS/6350.

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Santander Universidades
A popularização do uso de redes sociais virtuais em camadas cada vez mais jovens da sociedade vem tornando-se parte do cotidiano. Neste sentido, surgem novas implementações de Rede Social, como a Rede Social Espontânea (RSE). Ao contrário das redes sociais tradicionais, em que as interações sociais geralmente são uma extensão de relacionamentos existentes no mundo real, uma RSE parte da premissa de que não existe necessidade de relacionamento prévio entre os participantes. Considerando que mesmo em grupos formados por participantes que se conhecem de longa data não é possível assegurar qualquer tipo de interação ativa virtual, em redes sociais espontâneas esse fato poderia tornar-se motivo para desestímulo a sua utilização. O presente trabalho tem como objetivo a construção de um modelo capaz de extrair informações de grupos utilizando redes sociais, permitindo determinar o perfil do grupo a partir das informações extraídas dos históricos contextuais dos seus usuários membros, e, com isso recomendar recursos capazes de influenciar a interação entre os membros. Nesse cenário se enquadra o INTERACT, um modelo que possui como principal contribuição científica utilizar os históricos contextuais dos usuários de uma Rede Social Espontânea ou qualquer outra rede social para incentivar interações entre seus participantes. A utilização desses históricos como recurso para potencializar interações foi identificado como um diferencial em relação aos trabalhos relacionados da área os quais, em sua maioria, empregam somente o contexto atual como forma de gerar ações pontuais e sem relacionamento com outros participantes. Para avaliação do modelo, um grupo de voluntários foi convidado a participar de um experimento onde o INTERACT interagiu com o grupo através de um personagem criado. A análise foi realizada quantitativamente e qualitativamente, através da coleta dos números gerados pelas interações entre os participantes, registro de atividades e questionários. Os resultados apontam aumento no volume de interações entre participantes nos momentos de atuação do protótipo. Os participantes ainda relataram a influência positiva das ações do personagem gerenciado pelo protótipo, reconhecido por parte do grupo como "membro" mais influente.
The popularization of the use of virtual social networks in increasingly young layers of society has become part of daily life. In this sense, new implementations of Social Network, such as the Spontaneous Social Network (SSN), emerge. Unlike traditional social networks, where social interactions are often an extension of existing relationships in the real world, SSN starts from the premise that there is no need for prior relationships between participants. Considering that even in groups formed by participants that are known for a long time it is not possible to assure any kind of virtual active interaction, in spontaneous social networks this fact could become reason to discourage its use. The objective of this work is the construction of a model capable of extracting information from groups using social networks, allowing determining the profile of the group from the information extracted from the contextual histories of its member users, and with this to recommend resources capable of influencing the Interaction between members. In this scenario, INTERACT is a model that has as main scientific contribution to use the contextual histories of the users of a Spontaneous Social Network or any other social network to encourage interactions among its participants. The use of historical as a resource to enhance the interactions was identified as a difference in relation to the works related to the areas of which, for the most part, only use the current context as a way to generate punctual actions and without relationship with other participants. For the evaluation of the model, a group of volunteers was invited to participate in an experiment in which INTERACT interacted with the group through a person created. The analysis was performed quantitatively and qualitatively, through the collection of numbers generated in interactions among the participants, activity records and questionnaires. The results indicate an increase in the volume of interactions between the participants in the moments of performance of the prototype. The participants also reported a positive influence of the actions of the person managed by the prototype, recognized by the group as a influential "member".

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31

Ross, David Andrew. "Securing IEEE 802.11 wireless LANs". Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/37638/1/David_Ross_Thesis.pdf.

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As the acceptance and popularity of wireless networking technologies has proliferated, the security of the IEEE 802.11 wireless local area network (WLAN) has advanced in leaps and bounds. From tenuous beginnings, where the only safe way to deploy a WLAN was to assume it was hostile and employ higherlayer information security controls, to the current state of the art, all manner of improvements have been conceived and many implemented. This work investigates some of the remaining issues surrounding IEEE 802.11 WLAN operation. While the inherent issues in WLAN deployments and the problems of the original Wired Equivalent Privacy (WEP) provisions are well known and widely documented, there still exist a number of unresolved security issues. These include the security of management and control frames and the data link layer protocols themselves. This research introduces a novel proposal to enhance security at the link layer of IEEE 802.11 WLANs and then conducts detailed theoretical and empirical investigation and analysis of the eects of such proposals. This thesis �rst de�nes the state of the art in WLAN technology and deployment, including an overview of the current and emerging standards, the various threats, numerous vulnerabilities and current exploits. The IEEE 802.11i MAC security enhancements are discussed in detail, along with the likely outcomes of the IEEE 802.11 Task Group W1, looking into protected management frames. The problems of the remaining unprotected management frames, the unprotected control frames and the unprotected link layer headers are reviewed and a solution is hypothesised, to encrypt the entire MAC Protocol Data Unit (MPDU), including the MAC headers, not just the MAC Service Data Unit (MSDU) commonly performed by existing protocols. The proposal is not just to encrypt a copy of the headers while still using cleartext addresses to deliver the frame, as used by some existing protocols to support the integrity and authenticity of the headers, but to pass the entire MPDU only as ciphertext to also support the con�dentiality of the frame header information. This necessitates the decryption of every received frame using every available key before a station can determine if it is the intended recipient. As such, this raises serious concerns as to the viability of any such proposal due to the likely impact on throughput and scalability. The bulk of the research investigates the impacts of such proposals on the current WLAN protocols. Some possible variations to the proposal are also provided to enhance both utility and speed. The viability this proposal with respect to the eect on network throughput is then tested using a well known and respected network simulation tool, along with a number of analysis tools developed speci�cally for the data generated here. The simulator's operation is �rst validated against recognised test outputs, before a comprehensive set of control data is established, and then the proposal is tested and and compared against the controls. This detailed analysis of the various simulations should be of bene�t to other researchers who need to validate simulation results. The analysis of these tests indicate areas of immediate improvement and so the protocols are adjusted and a further series of experiments conducted. These �nal results are again analysed in detail and �nal appraisals provided.

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32

Ludovici, Alessandro. "New Architectures for ubiquitous networks : use and adaptation of internet protocols over wireless sensor networks". Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/279288.

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This thesis focuses on the study of low-resource demanding protocols, communication techniques and software solutions to evaluate, optimise and implement Web service in WSNs. We start analysing the Web service architectures in order to choose the most appropriate for the constraints of WSNs, which is REST. Based on this analysis, we review the state-of-the-art of protocols that allows implementing REST Web services. To this end, we adopt the IEEE 802.15.4 standard for the physical and data-link layers, 6LoWPAN for the network layer and CoAP for the application layer. 6LoWPAN defines two forwarding techniques, which are called mesh under (MU) and route over (RO). It also provides a mechanism to fragment packets, which is called 6LoWPAN fragmentation. In part of the thesis, we study the effects that MU and RO have on communications using 6LoWPAN fragmentation. In particular, MU does not prevent forwarding unnecessary fragments and out-of-order delivery, which could lead to an inefficient use of bandwidth and a growth of energy consumption. We propose, then, a novel technique able to improve the performance of MU with fragmented packets, which we refer to as controlled mesh under (CMU). The results of a performance evaluation in a real WSN show that CMU is able to enhance the performance of MU by reducing its packet loss and end-to-end delay. In 6LoWPAN fragmentation, the loss of a fragment forces the retransmission of the entire packet. To overcome this limitation, CoAP defines blockwise transfer. It splits the packet into blocks and sends each one in reliable transactions, which introduces a significant communication overhead. We propose a novel analytical model to study blockwise and 6LoWPAN fragmentation, which is validated trough Monte Carlo simulations. Both techniques are compared in terms of reliability and delay. The results show that 6LoWPAN fragmentation is preferable for delay-constrained applications. For highly congested networks, blockwise slightly outperforms 6LoWPAN fragmentation in terms of reliability. CoAP defines the observe option to allow a client to register to a resource exposed by a server and to receive updates of its state. Existing QoS in the observe option supports partially timeliness. It allows specifying the validity of an update but it does not guarantee its on-time delivery. This approach is inefficient and does not consider applications, i.e. e-health, that requires the delivery of an update within a deadline. With this limitation in mind, we design and evaluate a novel mechanism for update delivery based on priority. The evaluation proves that implementing a delivery order improves the delay and delivery ratio of updates. Our proposal is also able to reduce the energy consumption allowing clients to express the class of updates that they wish to receive. In part of this thesis, we present our original library for TinyOS, which we referred to as TinyCoAP, and the design and implementation of a CoAP proxy. We compare TinyCoAP to CoapBlip, which is the CoAP implementation distributed with TinyOS. TinyCoAP proves to be able to reach a high code optimization and to reduce the impact over the memory of WSN nodes. The evaluation includes also the analysis of the CoAP reliability mechanism, which was still uncovered in the literature. As a novelty, we also compare CoAP with HTTP considering different solutions for the transport layer protocol such as UDP and persistent TCP connections. The CoAP proxy enables Web applications to transparently access the resources hosted in CoAP devices. It supports long-lived communications by including the WebSocket protocol. It also supports Web applications that use the traditional HTTP long-polling technique. Finally, one of the main contributions of the proxy design is the proposal of a standard URI path format to be used by Web applications to access to a CoAP resource.
Esta tesis se enfoca en el estudio de protocolos de bajo consumo, técnicas de comunicación y software con el fin de evaluar, optimizar y desarrollar servicios Web en WSNs. Empezamos analizando la arquitectura de servicios Web con el objetivo de elegir la arquitectura más apropiada debido a las limitaciones de WSNs. Ésta se denomina REST. En base a este análisis, revisamos el estado del arte de los protocolos que permiten desarrollar servicios Web. Con este objetivo adoptamos el estándar IEEE 802.15.4 por la capa física y de enlace, 6LoWPAN por la de red y CoAP por la capa de aplicación. 6LoWPAN define dos técnicas de enrutamiento, denominadas 'Mesh Under' (MU) y 'Route Over' (RO). Asimismo ofrece un mecanismo para fragmentar paquetes, llamado 6LoWPAN fragmentation. En parte de la tesis estudiamos los efectos que MU y RO tienen sobre la comunicación que utiliza 6LoWPAN fragmentation. En particular, MU no previene enrutar fragmentos innecesarios y la entrega fuera de orden, lo cual podría provocar un uso ineficiente de ancho de banda y un crecimiento del consumo energía. Proponemos entonces nueva técnica capaz de mejorar las prestaciones de MU con paquetes fragmentados que denominamos 'Controlled Mesh Under' (CMU). Los resultados de una evaluación en una WSN real demuestran que CMU es capaz de mejorar las prestaciones de MU reduciendo la pérdida de paquetes y el retraso end-to-end. En 6LoWPAN fragmentation, la pérdida de un fragmento causa la retransmisión del paquete entero. Para evitar esta limitación CoAP define blockwise transfer. Esto divide el paquete en bloques y los envía en comunicaciones fiables provocando overhead. Proponemos un nuevo modelo analítico para estudiar blockwise y 6LoWPAN fragmentation cuya validación se realiza mediante simulaciones de Monte Carlo. Ambas técnicas se comparan en términos de fiabilidad y retraso. Los resultados muestran que es preferible usar 6LoWPAN fragmentation para las aplicaciones con restricciones en retraso. Para las redes mas congestionadas, blockwise mejora ligeramente 6LoWPAN fragmentation en términos de fiabilidad. CoAP define la opción observe para permitir a un cliente registrarse a un recurso proporcionado por un servidor y recibir actualizaciones de su estado. La QoS ofrecida por la opción observe proporciona soporte parcial por el timeliness. Esta permite especificar la validez de una actualización pero no garantiza su entrega a tiempo. Este enfoque es ineficiente y no incluye aplicaciones, como por ejemplo e-health que requieren la entrega de las actualizaciones en un plazo determinado. Teniendo en cuenta esta limitación, diseñamos y evaluamos un mecanismo novedoso para la entrega de actualizaciones basada en la prioridad. La evaluación demuestra que la implementación de una orden de entrega mejora la tasa de llegada y el retraso de las actualizaciones. Nuestra propuesta es capaz de reducir el consumo de energía permitiendo a los clientes expresar el tipo de actualización que desean recibir. En parte de esta tesis presentamos nuestra librería original pro TinyOS a la que nos referimos como TinyCoAP, así como el diseño y desarrollo de un Proxy CoAP. Comparamos TinyCoAP a CoapBlip, que es la aplicación distribuida con TinyOS. TinyCoAP demuestra ser capaz de alcanzar una alta optimización de código y reducir el impacto sobre la memoria de nodos de WSNs. La evaluación también incluye el análisis de la fiabilidad de CoAP que no había sido estudiada en la literatura. Como novedad también comparamos CoAP con HTTP, considerando diferentes soluciones para el protocolo de transporte como UDP y conexiones TCP persistentes. El Proxy CoAP permite a las aplicaciones Web acceder de manera transparente a los recursos almacenados en dispositivos CoAP. Éste incluye el protocolo WebSocket, que permite el establecimiento de conexiones long-lived. También permite el uso de aplicaciones Web con la tradicional técnica HTTP long-polling

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Ndiwalana, Ali. "Ubiquitous Computing: By the People, For the People". Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/33848.

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Computing is moving away from the desktop, permeating into many everyday objects and the environments in which we live. Many researchers in ubiquitous computing are excited about the potential to profoundly change the way we live by revolutionizing how we interact with information. Despite the excitement, few successful applications are making the transition from the laboratories to the mass market. While this could easily be attributed to the immaturity of the research area, it is also a manifestation of a larger problemâ the lack of coherent methods, processes or tools that assist designers in thinking about issues pertinent to ubiquitous computing, as they explore potential ideas and develop some of these into working prototypes. To this end, this research presents an overview of the important characteristics of ubiquitous computing systems identified by many of the leading researchers in the field. Contrasting with conventional systems, we discuss the resulting issues and challenges, and their implications on the future directions of this emerging research area. In a case study, we use scenario-based design to walkthrough the design of a community computing application. At various stages of the design process, the need to focus on more issues relevant to ubiquitous computing design became apparent, resulting in the augmentation of scenario-based design. The augmented scenario-based design process is proposed as a tool for helping designers conceptualize user activities within given usage circumstances and at various stages of the design process. New questions help to identify the most common pitfalls, enabling designers to produce systems that are more socially acceptable and provide a higher likelihood for adoption by everyday users beyond the laboratory. In initial testing, the augmented process was shown to produce better designs. The ultimate ambition of ubiquitous computing technology is to be able to serve users anywhere, at anytime. However, taking into account the dynamic nature of user needs and usage situations, is a novel and non trivial undertaking. In essence, it is a fundamental change that requires designers to rethink many of the conventional answers and processes that help guide the creation of interactive systemsâ We provide a promising approach.
Master of Science

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Clark, David. "Electromagnetic fast-transients in LV networks with ubiquitous small-scale embedded generation". Thesis, Cardiff University, 2012. http://orca.cf.ac.uk/37154/.

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Small-scale embedded generation projects rated below 16A per phase are being integrated into low-voltage distribution networks in ever increasing numbers. Seen from the network operator's perspective as little more than negative load, the commissioning of such generators is subject to compliance with the Fit and Forget connection requirements of ENA Engineering Recommendation G83/1. This thesis has sought to quantify the electromagnetic switching transient implications of integrating very large volumes of embedded generation into the UK's low-voltage supply networks. Laboratory testing of a converter-interfaced PV source has been undertaken to characterise typical switching transient waveshapes, and equivalent representative source models have been constructed in EMTP-ATP. A detailed frequency-dependent travelling wave equivalent of the DNO-approved Generic UK LV Distribution network model has been developed and, by means of extensive statistical simulation studies, used to quantify the cumulative impact of geographically localised generators switching in response to common network conditions. It is found that the magnitude of generator-induced voltage and current transients is dependent on the number of concurrently switched generators, and on their relative locations within the network. A theoretical maximum overvoltage of 1.72pu is predicted at customer nodes remote from the LV transformer terminals, for a scenario in which all households have installed embedded generation. Latent diversity in switch pole closing and inrush inception times is found to reduce predicted peak transient voltages to around 25-40% of their theoretical maxima.

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Guenkova-Luy, Teodora. "Multimedia networking coordination of multimedia services in next generation mobile networks". Saarbrücken VDM, Müller, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=3037222&prov=M&dok_var=1&dok_ext=htm.

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Chen, Longbiao. "Big data-driven optimization in transportation and communication networks". Electronic Thesis or Diss., Sorbonne université, 2018. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2018SORUS393.pdf.

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L'évolution des structures métropolitaines ont créé divers types de réseaux urbains. Parmi lesquels deux types de réseaux sont d'une grande importance pour notre vie quotidienne : les réseaux de transport correspondant à la mobilité humaine dans l'espace physique et les réseaux de communications soutenant les interactions humaines dans l'espace numérique. L'expansion rapide dans la portée et l'échelle de ces deux réseaux soulève des questions de recherche fondamentales sur la manière d’optimiser ces réseaux. Certains des objectifs principaux comprennent le provisioning de ressources à la demande, la détection des anomalies, l'efficacité énergétique et la qualité de service. Malgré les différences dans la conception et les technologies de mise en œuvre, les réseaux de transport et les réseaux de communications partagent des structures fondamentales communes, et présentent des caractéristiques spatio-temporelles dynamiques similaires. En conséquence, ils existent les défis communs dans l’optimisation de ces deux réseaux : le profil du trafic, la prédiction de la mobilité, l’agrégation de trafic, le clustering des nœuds et l'allocation de ressources. Pour atteindre les objectifs d'optimisation et relever les défis de la recherche, différents modèles analytiques, algorithmes d'optimisation et systèmes de simulation ont été proposés et largement étudiés à travers plusieurs disciplines. Ces modèles analytiques sont souvent validés par la simulation et pourraient conduire à des résultats sous-optimaux dans le déploiement. Avec l'émergence de l’Internet, un volume massif de données de réseau urbain peuvent être collecté. Les progrès récents dans les techniques d'analyse de données Big Data ont fourni aux chercheurs de grands potentiels pour comprendre ces données. Motivé par cette tendance, l’objectif de cette thèse est d'explorer un nouveau paradigme d'optimisation des réseaux basé sur les données. Nous abordons les défis scientifiques mentionnés ci-dessus en appliquant des méthodes d'analyse de données pour l'optimisation des réseaux. Nous proposons deux algorithmes data-driven pour le clustering de trafic réseau et la prédiction de la mobilité d’utilisateur, et appliquer ces algorithmes à l'optimisation dans les réseaux de transport et de communications. Premièrement, en analysant les jeux de données de trafic à grande échelle des deux réseaux, nous proposons un algorithme de clustering à base de graphe pour mieux comprendre les similitudes de la circulation et les variations de trafic entre différents zones et heures. Sur cette base, nous appliquons l'algorithme d’agrégation (clustering) de trafic aux deux applications d'optimisation de réseau suivants : 1. Un clustering de trafic dynamique pour la planification à la demande des réseaux de vélos partagés. Dans cette application, nous regroupons dynamiquement les stations de vélos avec des motifs de trafic similaires pour obtenir des demandes de trafic groupées (en cluster) plus stables et plus prédictible, de manière à pouvoir prévoir les stations surchargés dans le réseau et à permettre une planification dynamique de réseau en fonction de la demande. Les résultats d'évaluation en utilisant les données réelles de New York City et Washington, D.C. montrent que notre solution prévoit précisément des clusters surchargés [...]
The evolution of metropolitan structures and the development of urban systems have created various kinds of urban networks, among which two types of networks are of great importance for our daily life, the transportation networks corresponding to human mobility in the physical space, and the communication networks supporting human interactions in the digital space. The rapid expansion in the scope and scale of these two networks raises a series of fundamental research questions on how to optimize these networks for their users. Some of the major objectives include demand responsiveness, anomaly awareness, cost effectiveness, energy efficiency, and service quality. Despite the distinct design intentions and implementation technologies, both the transportation and communication networks share common fundamental structures, and exhibit similar spatio-temporal dynamics. Correspondingly, there exists an array of key challenges that are common in the optimization in both networks, including network profiling, mobility prediction, traffic clustering, and resource allocation. To achieve the optimization objectives and address the research challenges, various analytical models, optimization algorithms, and simulation systems have been proposed and extensively studied across multiple disciplines. Generally, these simulation-based models are not evaluated in real-world networks, which may lead to sub-optimal results in deployment. With the emergence of ubiquitous sensing, communication and computing diagrams, a massive number of urban network data can be collected. Recent advances in big data analytics techniques have provided researchers great potentials to understand these data. Motivated by this trend, we aim to explore a new big data-driven network optimization paradigm, in which we address the above-mentioned research challenges by applying state-of-the-art data analytics methods to achieve network optimization goals. Following this research direction, in this dissertation, we propose two data-driven algorithms for network traffic clustering and user mobility prediction, and apply these algorithms to real-world optimization tasks in the transportation and communication networks. First, by analyzing large-scale traffic datasets from both networks, we propose a graph-based traffic clustering algorithm to better understand the traffic similarities and variations across different area and time. Upon this basis, we apply the traffic clustering algorithm to the following two network optimization applications. 1. Dynamic traffic clustering for demand-responsive bikeshare networks. In this application, we dynamically cluster bike stations with similar usage patterns to obtain stable and predictable cluster-wise bike traffic demands, so as to foresee over-demand stations in the network and enable demand-responsive bike scheduling. Evaluation results using real-world data from New York City and Washington, D.C. show that our framework accurately foresees over-demand clusters (e.g. with 0.882 precision and 0.938 recall in NYC), and outperforms other baseline methods significantly. 2. Complementary traffic clustering for cost-effective C-RAN. In this application, we cluster RRHs with complementary traffic patterns (e.g., an RRH in residential area and an RRH in business district) to reuse the total capacity of the BBUs, so as to reduce the overall deployment cost. We evaluate our framework with real-world network data collected from the city of Milan, Italy and the province of Trentino, Italy. Results show that our method effectively reduces the overall deployment cost to 48.4\% and 51.7\% of the traditional RAN architecture in the two datasets, respectively, and consistently outperforms other baseline methods. Second, by analyzing large-scale user mobility datasets from both networks, we propose [...]

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Wacker, Arno Rüdiger. "Key distribution schemes for resource constrained devices in wireless sensor networks". [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-34332.

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Gräfenstein, Jürgen [Verfasser]. "Simultaneous Localization and Mapping in Wireless Networks Localization in Ubiquitous Infrastructures / Jürgen Gräfenstein". München : Verlag Dr. Hut, 2012. http://d-nb.info/1021719331/34.

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Kim, Hyoungsoo. "A simulation framework for traffic information dissemination in ubiquitous vehicular ad hoc networks". College Park, Md.: University of Maryland, 2007. http://hdl.handle.net/1903/7664.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2007.
Thesis research directed by: Dept. of Civil and Environmental Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Maliwatu, Richard. "Ubiquitous Mesh Networking: application to mobile communication and information dissemination in a rural context". Thesis, University of Cape Town, 2014. http://pubs.cs.uct.ac.za/archive/00000996/.

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ICT has furthered the social and economic development of societies but, rural African communities have lagged behind due to issues such as sparse population, low household income, a lack of electricity and other basic infrastructure that make it unattractive for telecommunication service providers to extend service provision. Where the service is available, ubiquitous service coverage has not translated into ubiquitous access for individuals because of the associated costs. A community-wide WMN offering VoIP using fixed telephone handsets has been deployed as a viable alternative to the cellular service provider. The effectiveness of this WMN VoIP service springs from the mobile phone usage statistics which showed that the majority of calls made are intra-community. This dissertation has been an effort towards improved communication and access to information for the under-served communities. Key contributions include, mobile VoIP support, translation gateway deployment to make textual information accessible in voice form via the phone, IP-based radio for community information dissemination. The lack of electricity has been mitigated by the use of low-power devices. In order to circumvent the computational challenges posed by the processing and storage limitations of these devices, a decentralised system architecture whereby the processing and storage load are distributed across the mesh nodes has been proposed. High-performance equipment can be stationed at the closest possible place with electricity in the area and connectivity extended to the non-electrified areas using low-power mesh networking devices. Implementation techniques were investigated and performance parameters measured. The quality of service experienced by the user was assessed using objective methods and QoS correlation models. A MOS value of 4.29, i.e. very good, was achieved for the mobile VoIP call quality, with the underlying hardware supporting up to 15 point-to-point simultaneous calls using SIP and the G.711 based codec. Using the PEAQ algorithm to evaluate the IP-based radio, a PEAQ value of 4.15, i.e. good, was achieved. Streaming audio across the network reduces the available bandwidth by 8Kbps per client due to the unicast nature of streaming. Therefore, a multicast approach has been proposed for efficient bandwidth utilization. The quality of the text-to-voice service rendered by the translation gateway had a PESQ score of 1.6 i.e. poor. The poor performance can be attributed to the TTS engine implementation and also to the lack of robustness in the time-alignment module of the PESQ algorithm. The dissertation also proposes the use of the WMN infrastructure as a back-haul to isles of WSNs deployed in areas of interest to provide access to information about environmental variables useful in decision making.

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Arabi, Agha Ihab. "Distributed and adaptive approaches for ubiquitous and pervasive computing". Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCA025.

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Le paradigme d'émergence spontanée de services (Spontaneous Emergence Paradigm, SEP) pour la mise en œuvre de l’informatique omniprésente ou diffuse (pervasive computing), consiste à fournir des services aux utilisateurs en fonction de leur environnement ad hoc. Ce paradigme a prouvé son efficacité et son adéquation aux applications distribuées sensibles au contexte. Ce travail se concentre sur deux aspects liés à la mise en œuvre des services SEP. Le premier se distingue de ce qui est proposé dans la littérature, par une approche physiologique de « Dead Reckoning » (Physiological Pedestrian Dead Reckoning Approach, PDR), qui permet de corriger les erreurs de positionnement à partir de données physiologiques comme la fréquence cardiaque et la vitesse de déplacement. Cette approche utilise des modèles stochastiques, qui reposent sur la distribution des probabilités des fréquences cardiaques précédemment collectées par rapport à la vitesse de déplacement de l’utilisateur (par exemple, par apprentissage via une marche sur un tapis roulant). Le modèle proposé permet ainsi d’ajuster les vitesses lues dans n’importe quel futur système PDR. Le deuxième aspect de cette recherche concerne la détection de réseaux d’affinités (Social Relationship Detection framework, SRD). Cette approche propose d’explorer le niveau d’affinité entre personnes en fonction de leur connexions et interactions selon plusieurs conditions. Ces connexions à des bornes WAP (Wireless Access Point), par rapport à chaque condition, sont consolidées pour former des distributions de probabilités. Par la suite, ces distributions de probabilités sont introduites dans un réseau de neurones (back propagation neural network) pour détecter et déterminer les affinités entre utilisateurs. Cette approche permet une prise de décision adaptative à chaque connexion au WAP et selon le comportement de l’utilisateur, contrairement aux approches classiques reposant uniquement sur une connaissance globale au préalable de la convergence des attributs des utilisateurs concernés
Service Emergence Paradigm (SEP), based on a pervasive computing approach, consists of providing services to users within intended applications, transparently from their intentions, relatively to their needs, and regardless of the time and devices used. This considered paradigm has been proved sufficiently in applications that have context awareness schemes and various working threads. This research focuses on two aspects for providing SEP services. This first aspect is to implement a Physiological Pedestrian Dead Reckoning Approach (PPDR) that corrects position errors in pedestrian dead reckoning systems based on the heart rate parameter. This approach uses specific stochastic models that rely on probability distributions of previously collected heart rate values with respect to their velocities of a user during a treadmill walk. The reason behind this collection is to form a pattern that contributes in adjusting currently read velocities in any future PDR system. The second aspect of this research is the Social Relationship Detection framework (SRD). This approach proposes a mean for exploring the level of relationship between people by observing the network connection pattern of each person over several conditions. These connections, with respect to each condition, are consolidated to form a set that holds different probability distributions. These distributions are formed based on the users’ Wireless Access Point (WAP) connection establishment routine. Afterwards, the distributions of the probabilities are fed into a trained back propagation neural network to detect the level of relationship between candidate users for forthcoming friendship recommendations. This approach is elaborated in a technique that achieves intelligent decision-making whenever the connection pattern to the WAP and the user behavior are changing with time. It is also distinguished from other classical approaches that rely solely on prior knowledge of the convergence of the users’ attributes

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Laibowitz, Matthew Joel 1975. "Creating cohesive video with the narrative-informed use of ubiquitous wearable and imaging sensor networks". Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/57695.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2010.
Page 232 blank. Cataloged from PDF version of thesis.
Includes bibliographical references (p. 222-231).
In today's digital era, elements of anyone's life can be captured, by themselves or others, and be instantly broadcast. With little or no regulation on the proliferation of camera technology and the increasing use of video for social communication, entertainment, and education, we have undoubtedly entered the age of ubiquitous media. A world permeated by connected video devices promises a more democratized approach to mass-media culture, enabling anyone to create and distribute personalized content. While these advancements present a plethora of possibilities, they are not without potential negative effects, particularly with regard to privacy, ownership, and the general decrease in quality associated with minimal barriers to entry. This dissertation presents a first-of-its-kind research platform designed to investigate the world of ubiquitous video devices in order to confront inherent problems and create new media applications. This system takes a novel approach to the creation of user-generated, documentary video by augmenting a network of video cameras integrated into the environment with on-body sensing. The distributed video camera network can record the entire life of anyone within its coverage range and it will be shown that it, almost instantly, records more audio and video than can be viewed without prohibitive human resource cost.
(cont.) This drives the need to develop a mechanism to automatically understand the raw audiovisual information in order to create a cohesive video output that is understandable, informative, and/or enjoyable to its human audience. We address this need with the SPINNER system. As humans, we are inherently able to transform disconnected occurrences and ideas into cohesive narratives as a method to understand, remember, and communicate meaning. The design of the SPINNER application and ubiquitous sensor platform is informed by research into narratology, in other words how stories are created from fragmented events. The SPINNER system maps low level sensor data from the wearable sensors to higher level social signal and body language information. This information is used to label the raw video data. The SPINNER system can then build a cohesive narrative by stitching together the appropriately labeled video segments. The results from three test runs are shown, each resulting in one or more automatically edited video piece. The creation of these videos is evaluated through review by their intended audience and by comparing the system to a human trying to perform similar actions. In addition, the mapping of the wearable sensor data to meaningful information is evaluated by comparing the calculated results to those from human observation of the actual video.
by Mathew Laibowitz.
Ph.D.

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Kenney, Joshua D., Chris J. Cunningham i Ben A. Abbott. "EVALUATION OF UBIQUITIOUS USE OF WIRELESS SENSOR NETWORK TECHNOLOGY IN DATA ACQUISITION AND TELEMETRY APPLICATIONS". International Foundation for Telemetering, 2007. http://hdl.handle.net/10150/604407.

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ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada
Industrial wireless sensor networks can be designed to meet the strict requirements of specific distributed applications. Emerging standards have enabled the development of low-cost, lowpower sensor nodes that are quickly becoming a commodity, enabling the realization of efficient and reliable data acquisition and telemetry in many systems. Moreover, new and exciting possibilities arise from the distributed computing power of the sensor nodes, the ability to monitor and aggregate data across large arrays of sensors, and the ability to model dynamic and rugged environments that were previously beyond the reach of traditional data acquisition and telemetry systems.

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Berlemont, Samuel. "Automatic non linear metric learning : Application to gesture recognition". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI014/document.

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Cette thèse explore la reconnaissance de gestes à partir de capteurs inertiels pour Smartphone. Ces gestes consistent en la réalisation d'un tracé dans l'espace présentant une valeur sémantique, avec l'appareil en main. Notre étude porte en particulier sur l'apprentissage de métrique entre signatures gestuelles grâce à l'architecture "Siamoise" (réseau de neurones siamois, SNN), qui a pour but de modéliser les relations sémantiques entre classes afin d'extraire des caractéristiques discriminantes. Cette architecture est appliquée au perceptron multicouche (MultiLayer Perceptron). Les stratégies classiques de formation d'ensembles d'apprentissage sont essentiellement basées sur des paires similaires et dissimilaires, ou des triplets formés d'une référence et de deux échantillons respectivement similaires et dissimilaires à cette référence. Ainsi, nous proposons une généralisation de ces approches dans un cadre de classification, où chaque ensemble d'apprentissage est composé d’une référence, un exemple positif, et un exemple négatif pour chaque classe dissimilaire. Par ailleurs, nous appliquons une régularisation sur les sorties du réseau au cours de l'apprentissage afin de limiter les variations de la norme moyenne des vecteurs caractéristiques obtenus. Enfin, nous proposons une redéfinition du problème angulaire par une adaptation de la notion de « sinus polaire », aboutissant à une analyse en composantes indépendantes non-linéaire supervisée. A l'aide de deux bases de données inertielles, la base MHAD (Multimodal Human Activity Dataset) ainsi que la base Orange, composée de gestes symboliques inertiels réalisés avec un Smartphone, les performances de chaque contribution sont caractérisées. Ainsi, des protocoles modélisant un monde ouvert, qui comprend des gestes inconnus par le système, mettent en évidence les meilleures capacités de détection et rejet de nouveauté du SNN. En résumé, le SNN proposé permet de réaliser un apprentissage supervisé de métrique de similarité non-linéaire, qui extrait des vecteurs caractéristiques discriminants, améliorant conjointement la classification et le rejet de gestes inertiels
As consumer devices become more and more ubiquitous, new interaction solutions are required. In this thesis, we explore inertial-based gesture recognition on Smartphones, where gestures holding a semantic value are drawn in the air with the device in hand. In our research, speed and delay constraints required by an application are critical, leading us to the choice of neural-based models. Thus, our work focuses on metric learning between gesture sample signatures using the "Siamese" architecture (Siamese Neural Network, SNN), which aims at modelling semantic relations between classes to extract discriminative features, applied to the MultiLayer Perceptron. Contrary to some popular versions of this algorithm, we opt for a strategy that does not require additional parameter fine tuning, namely a set threshold on dissimilar outputs, during training. Indeed, after a preprocessing step where the data is filtered and normalised spatially and temporally, the SNN is trained from sets of samples, composed of similar and dissimilar examples, to compute a higher-level representation of the gesture, where features are collinear for similar gestures, and orthogonal for dissimilar ones. While the original model already works for classification, multiple mathematical problems which can impair its learning capabilities are identified. Consequently, as opposed to the classical similar or dissimilar pair; or reference, similar and dissimilar sample triplet input set selection strategies, we propose to include samples from every available dissimilar classes, resulting in a better structuring of the output space. Moreover, we apply a regularisation on the outputs to better determine the objective function. Furthermore, the notion of polar sine enables a redefinition of the angular problem by maximising a normalised volume induced by the outputs of the reference and dissimilar samples, which effectively results in a Supervised Non-Linear Independent Component Analysis. Finally, we assess the unexplored potential of the Siamese network and its higher-level representation for novelty and error detection and rejection. With the help of two real-world inertial datasets, the Multimodal Human Activity Dataset as well as the Orange Dataset, specifically gathered for the Smartphone inertial symbolic gesture interaction paradigm, we characterise the performance of each contribution, and prove the higher novelty detection and rejection rate of our model, with protocols aiming at modelling unknown gestures and open world configurations. To summarise, the proposed SNN allows for supervised non-linear similarity metric learning, which extracts discriminative features, improving both inertial gesture classification and rejection

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Lee, Y. D. (Young-Dong). "Wireless vital signs monitoring system for ubiquitous healthcare with practical tests and reliability analysis". Doctoral thesis, Oulun yliopisto, 2010. http://urn.fi/urn:isbn:9789514263880.

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Abstract The main objective of this thesis project is to implement a wireless vital signs monitoring system for measuring the ECG of a patient in the home environment. The research focuses on two specific research objectives: 1) the development of a distributed healthcare system for vital signs monitoring using wireless sensor network devices and 2) a practical test and performance evaluation for the reliability for such low-rate wireless technology in ubiquitous health monitoring applications. The first section of the thesis describes the design and implementation of a ubiquitous healthcare system constructed from tiny components for the home healthcare of elderly persons. The system comprises a smart shirt with ECG electrodes and acceleration sensors, a wireless sensor network node, a base station and a server computer for the continuous monitoring of ECG signals. ECG data is a commonly used vital sign in clinical and trauma care. The ECG data is displayed on a graphical user interface (GUI) by transferring it to a PDA or a terminal PC. The smart shirt is a wearable T-shirt designed to collect ECG and acceleration signals from the human body in the course of daily life. In the second section, a performance evaluation of the reliability of IEEE 802.15.4 low-rate wireless ubiquitous health monitoring is presented. Three scenarios of performance studies are applied through practical tests: 1) the effects of the distance between sensor nodes and base-station, 2) the deployment of the number of sensor nodes in a network and 3) data transmission using different time intervals. These factors were measured to analyse the reliability of the developed technology in low-rate wireless ubiquitous health monitoring applications. The results showed how the relationship between the bit-error-rate (BER) and signal-to-noise ratio (SNR) was affected when varying the distance between sensor node and base-station, through the deployment of the number of sensor nodes in a network and through data transmission using different time intervals.

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García, Davis Ernesto J. "Contribution to the publish/subscribe communication model for the development of ubiquitous services in wireless sensor networks". Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667126.

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Advances in wireless technologies and the rapid development of integrated electronics have made wireless sensor networks (WSN) one of the key technologies of the Internet of Things (IoT). Thanks to the ability of these networks to measure the physical phenomena of their environment, process and communicate this information using wireless technologies, they have excelled in the development of applications that respond or adapt to the context of a user, as is the case of ubiquitous environments such as smart cities, industrial automation, e-health among others. In addition, the IoT has opened the possibility that intelligent objects or devices are also capable of exchanging status information, conditions and capacity in order to interact with each other, in the same way that human beings have done through systems based on presence. These systems require information of an event in real time to react in a timely manner to the conditions or context of the user or device. These applications open new challenges in the management of WSN resources, since these networks operate in environments that are generally prone to packet loss and consist of generally small nodes with limited resources in memory, processing, bandwidth and power. The main objective of this thesis is the development of several mechanisms that allow the adaptation of the Publish/Subscribe protocols to the characteristics and limitations of the WSN for the provision of ubiquitous services in the context of the IoT. In addition, QoS support is supplied through mechanisms that provide reliability and timeliness in the delivery of packets and data aggregation techniques are applied to be efficient in the power consumption and the WSN bandwidth. Our research proposes an architecture to provide a presence service for WSN based on a Publish/ Subscribe model distributed and focused on mechanisms such as the aggregation of data and the publication of messages on demand to achieve energy efficiency and bandwidth. All these mechanisms have been applied in the design of a system called PASH aimed at home control based on the concept of Ambient Assisted Living (AAL). The reliability provided by Publish/Subscribe protocols in WSN is of great importance in the design of applications that require receiving a message to react on time or in real time to an event. Initially, we focused our study on increasing the proportion of packet delivery (PDR) in the destination node through the improvement of reliability mechanisms. We evaluated the reliability mechanism of the MQTT-SN protocol and several proposed mechanisms of the CoAP protocol. From this evaluation, we propose a new and simple adaptive retransmission mechanism to respond to packet loss in the most appropriate way. Finally, we consider that applications such as: e-health, critical infrastructure control and monitoring, among others, must meet different QoS requirements, such as reliability and timeliness for each type of message received. In addition, data aggregation techniques play an important role in WSN to reduce power consumption and bandwidth. In this thesis, we propose a mechanism that provides the application with three different levels of QoS: we provide an improvement of our previous relay mechanism for reliability, we include the data aggregation in our reliability mechanism and we provide a timeliness mechanism in the delivery of packets.
Els avenços en les tecnologies sense fils i al ràpid desenvolupament de l'electrònica integrada, ha convertit les xarxes de sensors sense fils (WSN) en una de les tecnologies claus de l'Internet de les Coses (Iot). Gràcies a la capacitat que tenen aquestes xarxes de mesurar els fenòmens físics del seu entorn, processar i comunicar aquesta informació utilitzant tecnologies sense fils, s'han destacat en el desenvolupament d'aplicacions que responguin o s'adaptin al context d'un usuari, com és el cas dels entorns ubics com a ciutats intel·ligents, automatització industrial, salut electrònica entre d'altres. A més, el IOT ha obert la possibilitat que els objectes o dispositius intel·ligents també siguin capaços d'intercanviar informació d'estat, condicions i capacitat per tal d'interactuar entre si, de la mateixa manera que els éssers humans ho han fet a través de sistemes basats en presència. Aquests sistemes requereixen informació d'un esdeveniment en temps real per reaccionar de manera oportuna a les condicions o al context de l'usuari o dispositiu. Aquestes aplicacions obren nous desafiaments en l'administració dels recursos de WSN, ja que aquestes xarxes operen en entorns que generalment són propensos a la pèrdua de paquets i consten de nodes generalment petits amb recursos limitats en memòria, processament, ample de banda i alimentació. El principal objectiu d'aquesta tesi és el desenvolupament de diversos mecanismes que permetin l'adequació dels protocols d'Publish / Subscribe a les característiques i limitacions de la WSN per a la provisió de serveis ubics en el context de la IOT. A més, es brinda suport de QoS a través de mecanismes que proporcionen fiabilitat i puntualitat en el lliurament de paquets i s'apliquen tècniques d'agregació de dades per a ser eficients en el consum d'energia i l'ample de banda de la WSN. La nostra investigació proposa una arquitectura per a proporcionar un servei de presència per WSN basat en un model de Publish / Subscribe distribuït i centrat en mecanismes com ara l'agregació de dades i la publicació de missatges en demanda per aconseguir eficiència en l'energia i l'ample de banda . Tots aquests mecanismes han estat aplicats en el disseny d'un sistema anomenat Pash dirigit al control de la llar basat en el concepte de Vida Assistida (AAL). La fiabilitat proporcionada pels protocols de Publish / Subscribe WSN és de gran importància en el disseny d'aplicacions que requereixen rebre un missatge per reaccionar a temps o en temps real davant un esdeveniment. Inicialment enfoquem el nostre estudi en augmentar la proporció de lliurament de paquets (PDR) en el node de destinació a través de la millora dels mecanismes de fiabilitat. Avaluem el mecanisme de fiabilitat del protocol MQTT-SN i diversos mecanismes proposats del protocol COAP. A partir d'aquesta avaluació, proposem un nou i senzill mecanisme de retransmissió adaptable per respondre a la pèrdua de paquets de la manera més adequada. Finalment, considerem que les aplicacions com: salut electrònica, control d'infraestructura crítica i monitoratge, entre d'altres, han de complir diferents requisits de QoS, com la fiabilitat i la puntualitat per a cada tipus de missatge rebut. A més, les tècniques d'agregació de dades tenen un paper important en WSN per reduir el consum d'energia i l'ample de banda. En aquesta tesi, proposem un mecanisme que proporciona a la aplicació tres nivells de QoS diferents: proporcionem una millora del nostre mecanisme de retransmissió anterior per a la fiabilitat, incloem l'agregació de dades en el nostre mecanisme de fiabilitat i proporcionem un mecanisme de puntualitat en el lliurament de paquets.

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Yousaf, Faqir Zarrar [Verfasser]. "Seamless Handover in Mobile IP-based Next Generation Networks : A Cross-Layer Solution for Ubiquitous Communication over Optimized Routes in IPv6 Networks / Faqir Zarrar Yousaf". Aachen : Shaker, 2010. http://d-nb.info/1080766898/34.

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Patel, Shwetak Naran. "Infrastructure mediated sensing". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24829.

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Thesis (Ph.D.)--Computing, Georgia Institute of Technology, 2009.
Committee Chair: Abowd, Gregory; Committee Member: Edwards, Keith; Committee Member: Grinter, Rebecca; Committee Member: LaMarca, Anthony; Committee Member: Starner, Thad.

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Hassanzadeh, Reza. "A secure framework and related protocols for ubiquitous access to electronic health records using Java sim cards". Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/37589/1/Reza_Hassanzadeh_Thesis.pdf.

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Ubiquitous access to patient medical records is an important aspect of caring for patient safety. Unavailability of sufficient medical information at the point-ofcare could possibly lead to a fatality. The U.S. Institute of Medicine has reported that between 44,000 and 98,000 people die each year due to medical errors, such as incorrect medication dosages, due to poor legibility in manual records, or delays in consolidating needed information to discern the proper intervention. In this research we propose employing emergent technologies such as Java SIM Cards (JSC), Smart Phones (SP), Next Generation Networks (NGN), Near Field Communications (NFC), Public Key Infrastructure (PKI), and Biometric Identification to develop a secure framework and related protocols for ubiquitous access to Electronic Health Records (EHR). A partial EHR contained within a JSC can be used at the point-of-care in order to help quick diagnosis of a patient’s problems. The full EHR can be accessed from an Electronic Health Records Centre (EHRC) when time and network availability permit. Moreover, this framework and related protocols enable patients to give their explicit consent to a doctor to access their personal medical data, by using their Smart Phone, when the doctor needs to see or update the patient’s medical information during an examination. Also our proposed solution would give the power to patients to modify the Access Control List (ACL) related to their EHRs and view their EHRs through their Smart Phone. Currently, very limited research has been done on using JSCs and similar technologies as a portable repository of EHRs or on the specific security issues that are likely to arise when JSCs are used with ubiquitous access to EHRs. Previous research is concerned with using Medicare cards, a kind of Smart Card, as a repository of medical information at the patient point-of-care. However, this imposes some limitations on the patient’s emergency medical care, including the inability to detect the patient’s location, to call and send information to an emergency room automatically, and to interact with the patient in order to get consent. The aim of our framework and related protocols is to overcome these limitations by taking advantage of the SIM card and the technologies mentioned above. Briefly, our framework and related protocols will offer the full benefits of accessing an up-to-date, precise, and comprehensive medical history of a patient, whilst its mobility will provide ubiquitous access to medical and patient information everywhere it is needed. The objective of our framework and related protocols is to automate interactions between patients, healthcare providers and insurance organisations, increase patient safety, improve quality of care, and reduce the costs.

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Palafox-Albarrán, Javier [Verfasser], Walter [Akademischer Betreuer] Lang i Hans-Jörg [Akademischer Betreuer] Kreowski. "Spatial Statistical Data Fusion on Java-enabled Machines in Ubiquitous Sensor Networks / Javier Palafox-Albarrán. Gutachter: Walter Lang ; Hans-Jörg Kreowski. Betreuer: Walter Lang". Bremen : Staats- und Universitätsbibliothek Bremen, 2014. http://d-nb.info/1072158795/34.

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