The mature textile industry coupled with our familiarity and comfort level with fabrics and the possibility of seamless integration of electronic components such as sensors, processors, and power sources in the fabric opens up a new dimension of computing. The electronic textile presents a suitable substrate over which numerous applications can be developed. Location awareness is one such application that can reap the benefits of e-textiles such that it can be widely deployed at a reasonable cost for assisting visually impaired people or to provide navigational help during emergency situations. This thesis describes an autonomous, wearable location awareness system that will determine a user's location within a building given a map of that building. The thesis examines the issues, constraints, and challenges concerning the design of such a system. The two-part location awareness algorithm computes the location and orientation within a room as well as determines the user's movement between rooms. The efficacy of the proposed system is demonstrated with a wearable prototype. / Master of Science

Traffic congestion, high gas price and inadequate public transportation are major challenges for any country, business or individual. The traditional approach to solving these problems has been to improve public transportation and use greener energy. These approaches require huge investment, research and time, and can only be carried out by governments or businesses. An alternative solution seeks to reduce the number of vehicles on the road based on ridesharing. Nevertheless, ridesharing is not a popular form of public transportation. A ridesharing application involves planning and collaboration in setting up rides. Some of the concerns of users of these applications are social discomfort that arises due to lack of trust amongst co-passengers and inconvenience in scheduling rides. In this work we are trying to understand the perceptions of trust in a software application that integrates collaboration and social networks. We conducted a rideshare needs assessment survey conducted within the Virginia Tech community. The purpose behind this survey was to understand commuters travel patterns, their needs and to identify their preferences for private vehicles and public transit for a variety of travel needs. The survey results indicate that users are willing to increase participation in ridesharing programs if three core issues are addressed trust, convenience and incentives. Based on the results and analysis of our survey results we present an iPhone based ridesharing application that would leverage social networks to embed trust. To overcome the complexity in scheduling rides, we have made our application available on mobile phones (iPhone) so that users are connected on the go and make use of GPS for location awareness to plan their rides instantaneously. Our social software application is easy and intuitive to use, helps users find trusted rideshares and reduces the carbon footprint of the individual. / Master of Science

<p>This paper intends to describe the work and result of the design project Meet App. Meet App lets users interact around their current locations in a direct manner. The user experience is evaluated to get an understanding of the usefulness and interaction with this type of design. The project is related to the context-awareness research field where findings put the project in a greater whole. The result indicates usefulness and enjoyment interacting with the application, but because of the low number of participants the findings cannot be validated.</p>

This paper intends to describe the work and result of the design project Meet App. Meet App lets users interact around their current locations in a direct manner. The user experience is evaluated to get an understanding of the usefulness and interaction with this type of design. The project is related to the context-awareness research field where findings put the project in a greater whole. The result indicates usefulness and enjoyment interacting with the application, but because of the low number of participants the findings cannot be validated.

This paper introduces Express Location, a mobile web application, supporting drivers in delivery service in the daily coordination of work. Remote communication and cooperation takes place on a shared map view around the drivers’ locations and next stop, through a drawing/doodling tool and multiple visual object representations. The aim is to understand the working situation and the use of locations in the daily work to better support the coordination of mobile delivery work. / <p>© (2011) ACM. This is the author’s version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in <em>CSCW '11 Proceedings of the ACM 2011 conference on Computer supported cooperative work</em> http://doi.acm.org/10.1145/1958824.1958956</p>

Spatial subscriptions have been used to specify locations of interest in Distributed Event-based Systems (DEBSs). However, current DEBSs representations to support spatial subscriptions are not expressive enough to describe some forms of subscriptions in mobile settings. For instance, users are not allowed to specify a spatial subscription that refers to other more well-known locations, in case they are not familiar with the names of their current locations. In addition, the middleware in existing DEBSs does not support changes at runtime, and modification to these middleware systems to support spatial subscriptions are highly coupled with specific DEBS infrastructures. In this thesis, I argue that by enhancing the expressiveness of spatial subscriptions, a new model of mobile spatial subscriptions for location-aware services can be defined and a reusable plug-in implementation approach that supports existing DEBSs can be developed. This thesis first summarizes the essential abstractions to specify mobile spatial subscriptions, and analyze the expressiveness of existing DEBSs to support these abstractions. Second, it proposes a three-level mobile spatial subscription model, which supports the essential abstractions used to specify spatial subscriptions. The first level of the model handles subscriptions consisting of geometric coordinates; the second level supports subscriptions with location labels; the third level interprets subscriptions which specify locations by stating their dynamic properties. Next, a plug-in implementation approach is introduced, and hence, the three-level model can be integrated with different DEBSs with minimal modification to the middleware. The subscription model is implemented as a subscriber/publisher component, instead of directly modifying the existing DEBS. Finally, I develop a prototype system, Dynamic Mobile Subscription System (DMSS), and illustrate the usefulness and applicability of the three-level model and the plug-in implementation approach.

Advances in wireless technologies in the last ten years have created considerable opportunities as well as challenges for wireless body medical systems. The foremost challenge is how to build a reliable system connecting heterogeneous body sensors and actuators in an open system environment. In this dissertation, we present our work towards this goal. The system addresses four design issues: the underlying network architecture, the network scheduling disciplines, the location determination and tracking methods, and the embedded application execution architecture. We first present the design of an adaptive wireless protocol (MBStarPlus) to provide the basic wireless platform WBAN (Wireless Body Area Network). MBStarPlus is a real-time, secure, robust and flexible wireless network architecture. It is designed to utilize any low-power wireless radio as its physical layer. The TDMA mechanism is adopted for realtime data delivery. The time-slot length is adjustable for flexibility. Multiple technologies are utilized to provide reliability and security. We next investigate how to coordinate the body sensors/actuators that can optimally select from a range (maximum and minimum) of data rates. Two bandwidth scheduling algorithms are proposed. One is a greedy algorithm that works for sensors with limited computational capability. The other is the UMinMax scheduling algorithm that has better scalability and power-saving performance but is more computationally intensive. The third issue addressed in this proposal is how to achieve location determination and tracking by a mix of high-precision but expensive and lower-precision but cost-effective sensors. This is achieved by a novel collaborative location determination scheme ColLoc that can integrate different types of distance measurements into a location estimation algorithm by weighing them according to their precision levels. Through this, a localization service can be both cost-effective and sufficiently accurate. Fourth, in order to minimize the effects of long network latency when the body network scales up, we propose ControlInGateway, an architectural feature that allows a control application to be executed inside the network gateway without the host's involvement. With ControlInGateway, a wireless system could achieve the same control quality as a wired system. / text

Spatial subscriptions have been used to specify locations of interest in Distributed Event-based Systems (DEBSs). However, current DEBSs representations to support spatial subscriptions are not expressive enough to describe some forms of subscriptions in mobile settings. For instance, users are not allowed to specify a spatial subscription that refers to other more well-known locations, in case they are not familiar with the names of their current locations. In addition, the middleware in existing DEBSs does not support changes at runtime, and modification to these middleware systems to support spatial subscriptions are highly coupled with specific DEBS infrastructures. In this thesis, I argue that by enhancing the expressiveness of spatial subscriptions, a new model of mobile spatial subscriptions for location-aware services can be defined and a reusable plug-in implementation approach that supports existing DEBSs can be developed. This thesis first summarizes the essential abstractions to specify mobile spatial subscriptions, and analyze the expressiveness of existing DEBSs to support these abstractions. Second, it proposes a three-level mobile spatial subscription model, which supports the essential abstractions used to specify spatial subscriptions. The first level of the model handles subscriptions consisting of geometric coordinates; the second level supports subscriptions with location labels; the third level interprets subscriptions which specify locations by stating their dynamic properties. Next, a plug-in implementation approach is introduced, and hence, the three-level model can be integrated with different DEBSs with minimal modification to the middleware. The subscription model is implemented as a subscriber/publisher component, instead of directly modifying the existing DEBS. Finally, I develop a prototype system, Dynamic Mobile Subscription System (DMSS), and illustrate the usefulness and applicability of the three-level model and the plug-in implementation approach.

O problema de lidar com a mobilidade dos usuários existe desde que os dispositivos móveis se tornaram capazes de lidar com conteúdo multimídia e ainda é um dos desafios mais relevantes na área de redes de computadores. A arquitetura de Internet convencional é inadequada em lidar com um número cada vez maior de dispositivos móveis que estão tanto consumindo quanto produzindo conteúdo. Named Data Networking (NDN) é uma arquitetura de rede que pode potencialmente superar este desafio de mobilidade. Ela suporta a mobilidade do consumidor nativamente, mas não oferece o mesmo nível de suporte para a mobilidade de conteúdo. A mobilidade de conteúdo exige garantir que os consumidores consigam encontrar e recuperar o conteúdo desejado mesmo quando o produtor correspondente (ou o hospedeiro principal) não estiver disponível. Nesta tese, propomos o PDRM (Proactive Data Replication Mechanism), um mecanismo de replicação de dados proativo e consciente de localização, que aumenta a disponibilidade de conteúdo através da redundância de dados no contexto da arquitetura NDN. Ele explora os recursos disponíveis dos usuários finais na vizinhança para melhorar a disponibilidade de conteúdo, mesmo no caso da mobilidade do produtor. Ao longo da tese, discutimos o projeto do PDRM, avaliamos o impacto do número de provedores disponíveis na vizinhança e a capacidade de cache na rede em sua operação e comparamos seu desempenho com NDN padrão e duas propostas do estado-da-arte. A avaliação indica que o PDRM melhora o suporte à mobilidade de conteúdo devido ao uso de informações de popularidade dos objetos e recursos extras na vizinhança para ajudar a replicação pró-ativa. Os resultados mostram que o PDRM pode reduzir os tempos de download até 53,55%, o carregamento do produtor até 71,6%, o tráfego entre domínios até 46,5% e a sobrecarga gerada até 25% em comparação com NDN padrão e os demais mecanismos avaliados. / The problem of handling user mobility has been around since mobile devices became capable of handling multimedia content and is still one of the most relevant challenges in networking. The conventional Internet architecture is inadequate in dealing with an ever-growing number of mobile devices that are both consuming and producing content. Named Data Networking (NDN) is a network architecture that can potentially overcome this mobility challenge. It supports consumer mobility by design but fails to offer the same level of support for content mobility. Content mobility requires guaranteeing that consumers manage to find and retrieve desired content even when the corresponding producer (or primary host) is not available. In this thesis, we propose PDRM, a Proactive and locality-aware Data Replication Mechanism that increases content availability through data redundancy in the context of the NDN architecture. It explores available resources from end-users in the vicinity to improve content availability even in the case of producer mobility. Throughout the thesis, we discuss the design of PDRM, evaluate the impact of the number of available providers in the vicinity and in-network cache capacity on its operation, and compare its performance to Vanilla NDN and two state-of-the-art proposals. The evaluation indicates that PDRM improves content mobility support due to using object popularity information and spare resources in the vicinity to help the proactive replication. Results show that PDRM can reduce the download times up to 53.55%, producer load up to 71.6%, inter-domain traffic up to 46.5%, and generated overhead up to 25% compared to Vanilla NDN and other evaluated mechanisms.

O problema de lidar com a mobilidade dos usuários existe desde que os dispositivos móveis se tornaram capazes de lidar com conteúdo multimídia e ainda é um dos desafios mais relevantes na área de redes de computadores. A arquitetura de Internet convencional é inadequada em lidar com um número cada vez maior de dispositivos móveis que estão tanto consumindo quanto produzindo conteúdo. Named Data Networking (NDN) é uma arquitetura de rede que pode potencialmente superar este desafio de mobilidade. Ela suporta a mobilidade do consumidor nativamente, mas não oferece o mesmo nível de suporte para a mobilidade de conteúdo. A mobilidade de conteúdo exige garantir que os consumidores consigam encontrar e recuperar o conteúdo desejado mesmo quando o produtor correspondente (ou o hospedeiro principal) não estiver disponível. Nesta tese, propomos o PDRM (Proactive Data Replication Mechanism), um mecanismo de replicação de dados proativo e consciente de localização, que aumenta a disponibilidade de conteúdo através da redundância de dados no contexto da arquitetura NDN. Ele explora os recursos disponíveis dos usuários finais na vizinhança para melhorar a disponibilidade de conteúdo, mesmo no caso da mobilidade do produtor. Ao longo da tese, discutimos o projeto do PDRM, avaliamos o impacto do número de provedores disponíveis na vizinhança e a capacidade de cache na rede em sua operação e comparamos seu desempenho com NDN padrão e duas propostas do estado-da-arte. A avaliação indica que o PDRM melhora o suporte à mobilidade de conteúdo devido ao uso de informações de popularidade dos objetos e recursos extras na vizinhança para ajudar a replicação pró-ativa. Os resultados mostram que o PDRM pode reduzir os tempos de download até 53,55%, o carregamento do produtor até 71,6%, o tráfego entre domínios até 46,5% e a sobrecarga gerada até 25% em comparação com NDN padrão e os demais mecanismos avaliados. / The problem of handling user mobility has been around since mobile devices became capable of handling multimedia content and is still one of the most relevant challenges in networking. The conventional Internet architecture is inadequate in dealing with an ever-growing number of mobile devices that are both consuming and producing content. Named Data Networking (NDN) is a network architecture that can potentially overcome this mobility challenge. It supports consumer mobility by design but fails to offer the same level of support for content mobility. Content mobility requires guaranteeing that consumers manage to find and retrieve desired content even when the corresponding producer (or primary host) is not available. In this thesis, we propose PDRM, a Proactive and locality-aware Data Replication Mechanism that increases content availability through data redundancy in the context of the NDN architecture. It explores available resources from end-users in the vicinity to improve content availability even in the case of producer mobility. Throughout the thesis, we discuss the design of PDRM, evaluate the impact of the number of available providers in the vicinity and in-network cache capacity on its operation, and compare its performance to Vanilla NDN and two state-of-the-art proposals. The evaluation indicates that PDRM improves content mobility support due to using object popularity information and spare resources in the vicinity to help the proactive replication. Results show that PDRM can reduce the download times up to 53.55%, producer load up to 71.6%, inter-domain traffic up to 46.5%, and generated overhead up to 25% compared to Vanilla NDN and other evaluated mechanisms.