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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

On the Automatic Recognition of Human Activities using Heterogeneous Wearable Sensors

Lara Yejas, Oscar David 01 January 2012 (has links)
Delivering accurate and opportune information on people's activities and behaviors has become one of the most important tasks within pervasive computing. Its wide spectrum of potential applications in medical, entertainment, and tactical scenarios, motivates further research and development of new strategies to improve accuracy, pervasiveness, and eciency. This dissertation addresses the recognition of human activities (HAR) with wearable sensors in three main regards: In the rst place, physiological signals have been incorporated as a new source of information to improve the recognition accuracy achieved by conventional approaches, which rely on accelerometer signals solely. A new HAR system, Centinela, was born from such concept, employing structural feature extraction along with classier ensembles, and achieving over 95% of recognition accuracy. In the second place, real time activity recognition was enabled by Vigilante, a mobile HAR framework under the AndroidTM platform. Providing immediate feedback on the user's activities is especially benecial in healthcare and military applications, which may require alert triggering or support of decision making. The evaluation demonstrates that Vigilante is energy ecient while maintaining high accuracy (i.e., up to 96.8%) and low response time. The system features MECLA, a mobile library for the evaluation of classification algorithms, which is also suitable for further machine learning applications. Finally, the activity recognition accuracy is improved by two new strategies for decision fusion and selection in multiple classier systems: the failure product and the precision-recall dierence. The experimental analysis conrms that the presented methods are benecial, not only for recognizing human activities, but also for many other classication problems.
182

Personalizable architecture model for optimizing the access to pervasive ressources and services : Application in telemedicine

Nageba, Ebrahim 07 December 2011 (has links) (PDF)
The growing development and use of pervasive systems, equipped with increasingly sophisticated functionalities and communication means, offer fantastic potentialities of services, particularly in the eHealth and Telemedicine domains, for the benifit of each citizen, patient or healthcare professional. One of the current societal challenges is to enable a better exploitation of the available services for all actors involved in a given domain. Nevertheless, the multiplicity of the offered services, the systems functional variety, and the heterogeneity of the needs require the development of knowledge models of these services, systems functions, and needs. In addition, the distributed computing environments heterogeneity, the availability and potential capabilities of various human and material resources (devices, services, data sources, etc.) required by the different tasks and processes, the variety of services providing users with data, the interoperability conflicts between schemas and data sources are all issues that we have to consider in our research works. Our contribution aims to empower the intelligent exploitation of ubiquitous resources and to optimize the quality of service in ambient environment. For this, we propose a knowledge meta-model of the main concepts of a pervasive environment, such as Actor, Task, Resource, Object, Service, Location, Organization, etc. This knowledge meta-model is based on ontologies describing the different aforementioned entities from a given domain and their interrelationships. We have then formalized it by using a standard language for knowledge description. After that, we have designed an architectural framework called ONOF-PAS (ONtology Oriented Framework for Pervasive Applications and Services) mainly based on ontological models, a set of rules, an inference engine, and object oriented components for tasks management and resources processing. Being generic, extensible, and applicable in different domains, ONOF-PAS has the ability to perform rule-based reasoning to handle various contexts of use and enable decision making in dynamic and heterogeneous environments while taking into account the availability and capabilities of the human and material resources required by the multiples tasks and processes executed by pervasive systems. Finally, we have instantiated ONOF-PAS in the telemedicine domain to handle the scenario of the transfer of persons victim of health problems during their presence in hostile environments such as high mountains resorts or geographically isolated areas. A prototype implementing this scenario, called T-TROIE (Telemedicine Tasks and Resources Ontologies for Inimical Environments), has been developed to validate our approach and the proposed ONOF-PAS framework.
183

Context dependency analysis in ubiquitous computing

Baloch, Raheel Ali 17 February 2012 (has links) (PDF)
To provide users with personalized adaptive services only using the accessible computing resources in a cloud environment, context aware applications need to assimilate both the accessed and derived context, i.e. a combination of more than one sensed data and information in the environment. Context data dependency, dependency that arises between the context data producer and consumer, may get introduced in a system due to numerous reasons. But as the number of context dependencies for a service increases, the more complex the system becomes to manage. The thesis addresses issues of how to identify context dependencies, represent such context dependencies and then reduce them in a system. In the first part of the thesis, we present two efficient approaches to determine context dependency relations among various services in ubiquitous computing environment to help better analyse the pervasive services. One approach is based on graph theory, and we have used the topological sort to determine the context dependencies. The second approach is based on solving constraint networks which determines whether an entity is affected when the state of a certain other entity has its state changed, i.e. determining the dynamic nature of context dependency. In the second part of the thesis, we present a mode for representation of context dependencies within a system. Our model that represents context dependencies is based on set theory and first-order predicate logic. The context dependency representation model also represents alternative sources for context acquisition that can be utilized in a case in which the preferred context producers are not available to service the desired context to the relevant context consumer any more. Further, we try to reduce the context dependencies by presenting the idea of profile context, which is based on the proposal of an open framework for context acquisition, management and distribution. This heuristic approach is based on the idea of utilizing mobile nodes in an ad hoc overlay network with more resources than the context producer itself to store various contextual information under the banner of profile context, and further, provide profile context instead of each context individually based on the queries the nodes receive from the context consumers. Bringing together the context information and context updates from various sources, support for context aware decisions can be implemented efficiently in a mobile environment by addressing the issues of context dependency using profile context
184

Esoko and WhatsApp Communication in Ghana : Mobile Services such as Esoko and WhatsApp in Reshaping Interpersonal Digital Media Communication in Ghana

Cynthia, Salkovic January 2015 (has links)
The predominant use of mobile media such as SMS and MIM across various sectors in Ghana is incontrovertibly influencing and reshaping interpersonal communications. This paper looked at the use of the Esoko SMS and WhatsApp MIM platforms and how the use of these two dominant platforms are enhancing and reshaping digital communication in the rural and urban Ghana respectively, as barriers of socioeconomic factors limits the use of sophisticated technologies in the rural setting. This is done by employing Madianou and Miller's notion of polymedia” to draw on the moral, social and the emotional use of mobile media in enacting interpersonal relationships and communications whilst keeping in focus the recursive repercussions.
185

Self-describing objects with tangible data structures

Sinha, Arnab 28 May 2014 (has links) (PDF)
Pervasive computing or ambient computing aims to integrate information systems into the environment, in a manner as transparent as possible to the users. It allows the information systems to be tightly coupled with the physical activities within the environment. Everyday used objects, along with their environment, are made smarter with the use of embedded computing, sensors etc. and also have the ability to communicate among themselves. In pervasive computing, it is necessary to sense the real physical world and to perceive its "context" ; a high level representation of the physical situation. There are various ways to derive the context. Typically, the approach is a multi-step process which begins with sensing. Various sensing technologies are used to capture low level information of the physical activities, which are then aggregated, analyzed and computed elsewhere in the information systems, to become aware of the context. Deployed applications then react, depending on the context situation. Among sensors, RFID is an important emerging technology which allows a direct digital link between information systems and physical objects. Besides storing identification data, RFID also provides a general purpose storage space on objects, enabling new architectures for pervasive computing. In this thesis, we defend an original approach adopting the later use of RFID i.e. a digital memory integrated to real objects. The approach uses the principle where the objects self-support information systems. This way of integration reduces the need of communication for remote processing. The principle is realized in two ways. First, objects are piggybacked with semantic information, related to itself ; as self-describing objects. Hence, relevant information associated with the physical entities are readily available locally for processing. Second, group of related objects are digitally linked using dedicated or ad-hoc data structure, distributed over the objects. Hence, it would allow direct data processing - like validating some property involving the objects in proximity. This property of physical relation among objects can be interpreted digitally from the data structure ; this justifies the appellation "Tangible Data Structures". Unlike the conventional method of using identifiers, our approach has arguments on its benefits in terms of privacy, scalability, autonomy and reduced dependency with respect to infrastructure. But its challenge lies in the expressivity due to limited memory space available in the tags. The principles are validated by prototyping in two different application domains. The first application is developed for waste management domain that helps in efficient sorting and better recycling. And the second, provides added services like assistance while assembling and verification for composite objects, using the distributed data structure across the individual pieces.
186

Burden of care and health-related quality of life among caregivers of children with autism spectrum disorder

Khanna, Rahul, January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains x, 178 p. : ill. Vita. Includes abstract. Includes bibliographical references.
187

Percevoir l'interaction sociale dans le mouvement humain : études psychophysiologiques du développement typique et dans les troubles du spectre autistique / Perception of social interaction through human motion : psychophysiological studies in typical development and autism spectrum disorders

Roche, Laëtitia 06 December 2013 (has links)
L'interaction sociale représente l’une des difficultés majeures des patients atteints de troubles envahissants du développement (TED). Or, la perception des mouvements humains contribue à la mise en place des comportements sociaux et représenterait un « marqueur » du développement de la cognition sociale. Cette étude de suivi du regard et de pupillométrie visait à caractériser l’attention visuo-spatiale et la charge cognitive au cours de la perception de mouvements biologiques humains porteurs d'intention sociale (MHS) chez 139 participants typiques (PaTYP) et 62 patients atteints d’un TED (PaTED). Chez les PaTYP, l’exploration augmente pour les MHS. Chez les PaTED, un déficit d’exploration des MHS est corrélé à la sévérité de la symptomatologie autistique globale. Ces anomalies de l’attention visuo-spatiale des PaTED réduiraient leur accès à l’information sociale et pourraient participer au trouble de l’interaction sociale et de la communication. / Social interaction is one of the main difficulties for patients with pervasive developmental disorders (PDD). However, the perception of human movement contributes to the development of social behavior and represents a "marker" for the development of social cognition. This eye tracking and pupillometric study aims to characterize the visuospatial attention and cognitive load during perception of social human biological motion (SHM) in 139 typical participants (PaTYP) and 62 patients with ASD (PaTED). In PaTYP, exploration increases for SHM. In PaTED, deficit of the exploration of MHS is correlated with the severity of the global autistic symptomatology. These abnormalities of visuospatial attention in PaTED could reduce their access to social information and participate in social interaction and communication disorders.
188

Playful appropriations of hybrid space:combining virtual and physical environments in urban pervasive games

Alavesa, P. (Paula) 04 December 2018 (has links)
Abstract Modern urban space, technological infrastructure, and sociability combine into a hybrid space that is the arena for urban pervasive games. Over the past two decades the changes in this game arena have been stealthy although substantial. Technological developments have helped to achieve true mobility of gaming devices, increased precision in localization, improved connectivity, and reduced orchestration required per player. Current pervasive location-based games can be played anytime anywhere. Subsequently, doors have been opened for a growing number of commercial games. These changes demand a new conceptualization of the urban game arena. This thesis focuses on playful appropriations of hybrid space. Hybrid space is urban space that entails ubiquitous technologies. Therefore, playful appropriations of hybrid space are always, to some extent, digital as well as urban. Prior research has identified two metaphors for urban pervasive games —true mobility and true sociability. This thesis proposes an additional metaphor, called synchronicity, for binding together different realities in pervasive games. They can be anything from mirror world like realistic virtual environments, such as 3D virtual representations of a city, to abstract realities, such as the backstory of the game, or the space identity of a certain location. While location awareness is an important binding factor between the virtual and physical worlds in pervasive gameplay, synchronizable elements can be anything from encouraged collocated gameplay to semantic similarities between the combined realities. This thesis is based on five game constructs that have been specifically designed and implemented as pervasive research games. Research data has been collected and analyzed with a mixed methods approach from field trials conducted in the wild. Constructive research is complemented with a literature review that maps the characteristics of current location-based mobile games and the game space. The main contribution of this thesis is the identification of the digital, abstract, and physical layers of reality in digital urban pervasive games. The second contribution is the identification and categorization of the synchronizable elements that bind these realities together. This thesis offers initial insights into translating this knowledge into the design of future pervasive games. / Tiivistelmä Urbaanitila on jatkuvassa muutoksessa, sillä se muotoutuu ja järjestyy uudelleen siellä kulkevien kaupunkilaisten kautta. Ubiikin teknologian, ihmisten kanssakäymisen ja modernin tilakäsityksen yhteisvaikutuksesta syntyy niin sanottu hybriditila, joka muodostaa peliareenan monille pervasiivisille peleille. Viime vuosikymmeninä tällä peliareenalla on tapahtunut vaivihkaisia mutta perustavaa laatua olevia muutoksia. Pelilaitteista on tullut aidosti mobiileja, ja ne kulkevat kaikkialla pelaajien mukana. Pelijärjestely vaatii vähemmän vaivaa pelaajaa kohden, paikannuksen tarkkuus on parantunut ja muutosten kautta myös kaupallisia pelejä on enemmän saatavilla. Nykyisiä pervasiivisia sijaintipohjaisia pelejä voi pelata milloin vain ja missä vain. Edellä mainittu kehitys edellyttää pervasiivisten pelien ja pelitilan uudelleen konseptualisointia. Väitöstyön aihe ei ole pelillisyys sellaisenaan, vaan “pelillisyys ja sen hyödyntäminen hybriditilassa”. Hybriditila on aina urbaani ja sisältää ubiikkia teknologiaa, minkä vuoksi pelit tässä tilassa ovat lähes poikkeuksetta myös digitaalisia. Aiempi tutkimus esittää, että saavutetut kehitysaskeleet voi niputtaa kahden metaforan alle. Nämä metaforat ovat: aito mobiilius sekä aito sosiaalisuus. Tämä väitöskirja esittää kolmannen, vielä määrittelemättömän tai saavuttamattoman metaforan näiden jatkoksi: synkronisuus. Synkronisoitavat piirteet tai elementit sitovat todellisuuksia yhteen pervasiivisessa pelitilassa. Tilassa olevat todellisuudet voivat olla realistisia pelimaailman kaltaisia virtuaalitiloja tai abstrakteja todellisuuksia, kuten pelitarinan muodostama todellisuus tai jonkin tietyn paikan tilaidentiteetti. Vaikka sijaintipohjaisuus on tärkeä todellisuuksia yhdistävä piirre, synkronisoitavat elementit voivat olla muutakin kuin sijaintikoordinaatteja. Pervasiiviset pelit nivoutuvat pelaajiensa päivittäiseen elämään, mikä tekee pelin kontekstista erottamattoman osan peliä. Tämä ominaisuus oikeuttaa ”in the wild” -menetelmien käytön tutkimuksessa, mikä tarkoittaa, että pelaamista ja pelejä tarkkaillaan luonnossa todellisessa ympäristössään. Tässä väitöstyössä käytetään konstruktioina varta vasten tätä tutkimusta ajatellen suunniteltuja ja toteutettuja pervasiivisia tutkimuspelejeä. Konstruktiivista tutkimusta tukee lisäksi teoreettinen tutkimusosio, joka koostuu kirjallisuuskatsaukseen pohjautuvasta nykyisten sijaintipohjaisten pelien ja pelitilan kategorisoinnista. Pervasiiviset pelit nivoutuvat pelaajiensa päivittäiseen elämään, mikä tekee pelin kontekstista erottamattoman osan peliä. Tämä ominaisuus oikeuttaa ”in the wild” -menetelmien käytön tutkimuksessa, mikä tarkoittaa, että pelaamista ja pelejä tarkkaillaan luonnossa todellisessa ympäristössään. Tässä väitöstyössä käytetään konstruktioina varta vasten tätä tutkimusta ajatellen suunniteltuja ja toteutettuja pervasiivisia tutkimuspelejeä. Konstruktiivista tutkimusta tukee lisäksi teoreettinen tutkimusosio, joka koostuu kirjallisuuskatsaukseen pohjautuvasta nykyisten sijaintipohjaisten pelien ja pelitilan kategorisoinnista.
189

Infraestrutura para o desenvolvimento de aplicações com suporte a comercialização de serviços entre pares em ambientes pervasivos. / Infrastructure for the development of applications with support for commercialization of services between peers in pervasive environments.

SOUZA, Lucas Vieira de. 06 August 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-08-06T17:16:31Z No. of bitstreams: 1 LUCAS VIERA DE SOUZA - DISSERTAÇÃO PPGCC 2012..pdf: 7997009 bytes, checksum: e5aaa6bb999df33f4638781b37b9dde5 (MD5) / Made available in DSpace on 2018-08-06T17:16:31Z (GMT). No. of bitstreams: 1 LUCAS VIERA DE SOUZA - DISSERTAÇÃO PPGCC 2012..pdf: 7997009 bytes, checksum: e5aaa6bb999df33f4638781b37b9dde5 (MD5) Previous issue date: 2012-02-29 / Capes / O avanço dos recursos computacionais dos aparelhos portáteis e a convergência de novas funcionalidades nestes dispositivos, tem criado novas oportunidades para o universo da computação pervasiva. Esses novos atributos, aliados a facilidade de conectividade entre eles e a disponibilização de serviços móveis, tem motivado o compartilhamento e a bilhetagem de recursos entre os usuários desses dispositivos. São exemplos de serviços: o compartilhamento de conteúdo multimídia, o controle de equipamentos eletrônicos e eletrodomésticos, o acesso à Internet, entre outros. Os aplicativos móveis que oferecem a bilhetagem de recursos, em sua maioria, apresentam apenas formas de cobrança online, com necessidade de uma conexão com a internet para a validação das transações. ne, com a necessidade de uma conexão com a Internet para a validação das transações. Outras aplicações apresentam uma forma de cobrança offline, porém são soluções que necessitam de um hardware específico para o seu funcionamento, o que inviabiliza a adoção de diversos dispositivos já presentes no mercado. Tendo em vista esses aspectos, neste trabalho é apresentada uma infraestrutura para o desenvolvimento de aplicações com suporte a bilhetagem em modo offline e sem a necessidade de um hardware específico para seu funcionamento. A validação do trabalho foi realizada a partir da implementação de um estudo de caso de um serviço de envio de mensagens SMS, que encaminha mensagens texto para dispositivos celulares a partir da transferência de arquivos, demonstrando o suporte oferecido pela infraestrutura para o desenvolvimento de aplicações móveis que oferecem bilhetagem de recursos. / The improvement of computational resources of mobile devices and the convergence of new features in these devices has created new opportunities for the world of pervasive computing. These new attributes, combined with ease of connectivity between them and the provision of mobile services has motivated the sharing of resources and billing between the users of these devices. Examples of services: the sharing of multimedia content, the electronics control and appliances, Internet access, others. Mobile applications that offer resource billing, most of them, have only online charging, with the need of an Internet connection to validate transactions. Other applications presents offline charging, but they are solutions that require specific hardware for its operation, which prevents the adoption of devices already on the market. Considering these aspects, this work presents an infrastructure for developing applications that supports service billing, which offers a new way of charging. The infrastructure allows billing in offline mode without the need for specific hardware to function. The work validation was performed by implementing a case study of a service for sending SMS messages, which sends text messages to mobile phones through file transfer, showing the support offered by the infrastructure for the development of mobile applications that provide the service billing.
190

Gerenciamento de confiança em ambientes pervasivos. / Management of trust in pervasive environments.

SILVA FILHO, Olympio Cipriano da. 30 July 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-30T15:07:27Z No. of bitstreams: 1 OLYMPIO CIPRIANO DA SILVA FILHO - DISSERTAÇÃO PPGEE 2007..pdf: 1354330 bytes, checksum: 4271b1c8fe8556d562518fb586e85376 (MD5) / Made available in DSpace on 2018-07-30T15:07:27Z (GMT). No. of bitstreams: 1 OLYMPIO CIPRIANO DA SILVA FILHO - DISSERTAÇÃO PPGEE 2007..pdf: 1354330 bytes, checksum: 4271b1c8fe8556d562518fb586e85376 (MD5) Previous issue date: 2007-12-14 / Com o desenvolvimento tecnológico a computação está cada vez mais integrada ao cotidiano das pessoas. Esta integração faz parte de um novo paradigma da computação: o da Computação Pervasiva. Neste paradigma, a computação está sempre a disposição do usuário, em qualquer lugar, a qualquer momento, através de ambientes repletos de dispositivos computacionais embutidos em uma grande variedade de objetos do dia-a-dia das pessoas como, automóveis, telefones, etc. Nestes ambientes, os dispositivos interagem entre si através de serviços devendo ser capazes lidar com a grande variedade de protocolos de descoberta de serviços disponíveis. Ainda,essas interações entre os dispositivos podem ocorrer em ambientes sem infra-estrutura de redes de computadores e entre dispositivos que podem agir desonestamente. Neste trabalho, é desenvolvido um modelo para avaliar a confiança nos serviços nos ambientes pervasivos a partir de experiências e recomendações. Este modelo é implementado por um Gerenciador de Informação de Confiança o qual disponibiliza um mecanismo de tomada de decisão para realizar a seleção de clientes e provedores de serviço. Ainda, o Gerenciador de Informação de Confiança é integrado a um middleware para computação pervasiva, o Wings, possibilitando a descoberta de serviços confiáveis. Foram utilizadas simulações e uma aplicação de teste para avaliar o Gerenciador de Informação de Confiança e sua integração ao middleware Wings. A partir dos resultados obtidos observou-se que a solução apresentada se mostrou satisfatória para a utilização em ambientes pervasivos. / The development of technology is integrating computing to people every day life. This integration belongs to a new computing paradigm: the pervasive computing. In this paradigm, the computation is always available, in every place at any time, through environments crowd of computing devices embedded in a great variety of objects like cars,cell phones, etc. In these environments, devices interact through services and should be able to deal with different service announcement solutions available. These interactions can occur without computing network infrastructure andamong malicious devices. In this work, it is developed a model to evaluate service trust in pervasive environments from experiences and recommendations. This model is implemented by a Trust Information Manager that provides a mechanism to make trust based decision. This Trust Information Manager is integrated to a pervasive computing middle ware,called Wings, enabling trusted service discover. Simulations and a test application were used to evaluate theTrust Information Manager and its integration with the Wings middleware. From the results it could be seen that the presented solution is efficient and can be widely used in pervasive computing environments.

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