For the past recent years mobile developers and content providers have been aware of consumers’ engagement in online social networking. New opportunities are presented when using a mobile device as a medium for social interaction, also referred to as mobile social software. An ever growing effort aimed at various mobile design processes and applications have taken place. To achieve a widespread adoption of mobile social software amongst the main stream mobile consumer, several problem areas have to be taken into consideration, such as the technological possibilities and limitations of mobile phones, security issues regarding user privacy and the different aspects of consumers appeal for social media. This research looks into the overall situation of the current field of research and focuses on the interests in mobile social software amongst users. The study was geographically limited to Malmö, Sweden and focused on a population at the ages of 13-18.

This thesis investigates the possibilities of implementing a location awareness mechanism for the so-called lesswire localNavigator. The author claims that it is possible to implement such a mechanism within the given prerequisites and constraints, even though with today’s technology it may not be economically feasible. Due to the lesswire’s constraints: high accuracy (67%), high-resolution (12 m2) and no hardware modification allowed to the mobile device, the suggested scheme uses Time Difference Of Arrival technology (TDOA). The main advantage of TDOA, as stated in this thesis, is the fact that it is almost totally independent of the preferred wireless technology of the mobile device. TDOA technology therefore, can be applied to a wide range of wireless networks (primarily TDMA, CDMA, FDMA – based). A disadvantage of this scheme is the fact that the network infrastructure needs to be extremely well synchronized - which in turn implies higher costs. Depending on how the synchronization problem is solved, the proposed system may well be economically feasible in the near future.

The appropriate framework to capture and share location information with mobile applications enable the development of interfaces and interface techniques that empower users to obtain and share information on the go. As such, the work in this thesis makes two major contributions. First is the SeeVT framework, a locative backbone that uses currently-available data and equipment in the Virginia Tech and Blacksburg VA environments (e.g., wireless signal triangulation, GPS signals) to make available to applications the location of the device in use. Applications built on this framework have available knowledge of the region in which the user's device is located. Second is a set of four applications built on the SeeVT framework: SeeVT – Alumni Edition (a guide for alumni returning to campus, often after lengthy absences), the Newman Project (a library information system for finding books and other library resources), VTAssist (a information sharing system for disabled users), and SeeVT-Art (a guide for users in our local inn and conference center to learn about the art on display). Key in this contribution is our identification and discussion of three interface techniques that emerged from our development efforts: an images-first presentation of information, a lightweight mobile augmented reality style of interaction, and locative content affordances that provide ways to quickly input focused types of information in mobile situations. / Master of Science

Abstract The contemporary information age is equipped with rich and affordable telecommunication services. In the future, people have even more flexibility when true wireless Internet and real-time multimedia are provided seamlessly over heterogeneous wireless networks. Optimally combining the capacity and services of the current and emerging networks requires a holistic view of mobility, resource and service management. This thesis contributes to the research and development of these hybrid systems with three main contributions. Firstly, a system architecture for vertical handoff in location-aware heterogeneous wireless networks is proposed. The proposed architecture enables the mobile node to prepare for approaching vertical handoffs and wake-up a hotspot interface. The needed communication procedures are discussed, and inter-related issues of mobility and geolocation information are considered in proportion to usability, advantages and limitations. Secondly, a framework for the analysis of vertical handoff algorithm sensitivity to various mobility parameters including velocity, handoff delay and dwell time is introduced. Handoff smoothing with a dwell-timer is analyzed as one potential scheme for optimizing vertical handoff locally. It is compared to a power based algorithm to find out its sensitivity to the changes in effective data rates, velocity of the terminal and the amount of handoff delay. The analysis focuses on the transition region, having case studies on both moving-in and moving-out scenarios. An optimal value for dwell-timer is found through simulations, showing a performance gain over power based algorithm as a function of mean throughput. The analysis is extended also to a multiple network scenario. Thirdly, experimental results on the behaviour of protocols used in wireless IP networks are presented. Prototype systems demonstrate results of using Mobile IP with a fuzzy logic algorithm for vertical handoff in a heterogeneous network environment and the role of IPv6 when using a voice application in a wireless LAN environment. Latest contributions include developing plug-and-play middleware functionalities for Symbian mobile devices, extending the use of the earlier results to state-of-the-art mobile devices.

Continues field monitoring and searching sensor data remains an imminent element emphasizes the influence of the Internet of Things (IoT). Most of the existing systems are concede spatial coordinates or semantic keywords to retrieve the entail data, which are not comprehensive constraints because of sensor cohesion, unique localization haphazardness. To address this issue, we propose deep learning inspired sensor-rank consolidation (DLi-SRC) system that enables 3-set of algorithms. First, sensor cohesion algorithm based on Lyapunov approach to accelerate sensor stability. Second, sensor unique localization algorithm based on rank-inferior measurement index to avoid redundancy data and data loss. Third, a heuristic directive algorithm to improve entail data search efficiency, which returns appropriate ranked sensor results as per searching specifications. We examined thorough simulations to describe the DLi-SRC effectiveness. The outcomes reveal that our approach has significant performance gain, such as search efficiency, service quality, sensor existence rate enhancement by 91%, and sensor energy gain by 49% than benchmark standard approaches.

The modern organizations are becoming increasingly dependent on Information Technology (IT), which requires implementation of an effective management support on this area where the high investments achieved can add value for the companies. The intent of reducing the damage caused by unusual computer problems is to provide an active and complete technical assistance to the users. This support team, which is responsible for IT maintenance, was initially named help desk and later, it was modified to service desk due to its significance and the integrated services that were added in this work area. The high diversity of hardware and software besides the current user s demand, which increase the complexity of the technical assistance, creates a new request: the human resource allocation that provides an appropriate profile for solving different types of computers problems. Professionals, who don t have the proper expertise (work experience and practice) for specific maintenance, can bring unnecessary travel for the technician and work inactivity for the requester.This paper aims the adjustment of a service desk tool developed at the Federal University of Santa Maria. The remodelling involves a context-aware computing, location awareness and temporal context characteristics and the technician expertise. The main results demonstrate a service desk context-aware system (sdvpc-SC), that also enables its access through a mobile device and the improvement of technical calls distributed by expertise and geographical location. The tests proved that the system is technically possible and its adjustments can be easily implemented in different types systems of the same category. / As organizações modernas estão se tornando cada vez mais dependentes da Tecnologia da Informação (TI), o que torna imprescindível a implementação de um gerenciamento efetivo da TI para que os altos investimentos realizados no setor possam agregar valor às empresas. Quando surge um problema em algum equipamento de informática, ocasionando um funcionamento anormal dos serviços, espera-se que o usuário tenha uma resposta rápida e clara da equipe de suporte para minimizar os prejuízos causados. Esta equipe de suporte, responsável por resolver os problemas de TI, foi inicialmente denominada help desk, mas devido a sua importância e a novos serviços agregados a sua área de atuação passou a ser chamada de service desk. A grande diversidade de hardware e software aliada as atuais exigências dos usuários torna o atendimento mais complexo e cria uma nova demanda: a alocação de recursos humanos que apresentem o perfil adequado para resolução dos diferentes tipos de problemas. Alocar técnicos que não possuem a expertise (experiência e prática) correta para a solução do problema pode ocasionar, para o técnico, a perda de tempo pelo deslocamento desnecessário, e para o usuário a ociosidade devido à falta de solução do incidente no primeiro atendimento. Este trabalho apresenta a adaptação de uma ferramenta de service desk desenvolvida na Universidade Federal de Santa Maria. As adequações envolvem características da computação sensível ao contexto de localização, temporal e de expertise do técnico. Como principais resultados, obteve-se um sistema de service desk sensível ao contexto (sdvpc-SC), que possibilita o seu acesso através de dispositivo móvel, com a otimização das chamadas por expertise e a localização geográfica do técnico. Os testes demonstraram que o sistema é tecnicamente viável e as adaptações realizadas neste trabalho podem ser facilmente implementadas em diferentes tipos de sistemas da mesma categoria.

Spectrum, environment and location awareness are key characteristics of cognitive radio (CR). Knowledge of a user’s location as well as the surrounding environment type may enhance various CR tasks, such as spectrum sensing, dynamic channel allocation and interference management. This dissertation deals with the optimisation of adaptive localisation techniques for CR. The first part entails the development and evaluation of an efficient bandwidth determination (BD) model, which is a key component of the cognitive positioning system. This bandwidth efficiency is achieved using the Cramer-Rao lower bound derivations for a single-input-multiple-output (SIMO) antenna scheme. The performances of the single-input-single-output (SISO) and SIMO BD models are compared using three different generalised environmental models, viz. rural, urban and suburban areas. In the case of all three scenarios, the results reveal a marked improvement in the bandwidth efficiency for a SIMO antenna positioning scheme, especially for the 1×3 urban case, where a 62% root mean square error (RMSE) improvement over the SISO system is observed. The second part of the dissertation involves the presentation of a multiband time-of arrival (TOA) positioning technique for CR. The RMSE positional accuracy is evaluated using a fixed and dynamic bandwidth availability model. In the case of the fixed bandwidth availability model, the multiband TOA positioning model is initially evaluated using the two-step maximum-likelihood (TSML) location estimation algorithm for a scenario where line-of-sight represents the dominant signal path. Thereafter, a more realistic dynamic bandwidth availability model has been proposed, which is based on data obtained from an ultra-high frequency spectrum occupancy measurement campaign. The RMSE performance is then verified using the non-linear least squares, linear least squares and TSML location estimation techniques, using five different bandwidths. The proposed multiband positioning model performs well in poor signal-to-noise ratio conditions (-10 dB to 0 dB) when compared to a single band TOA system. These results indicate the advantage of opportunistic TOA location estimation in a CR environment. / Dissertation (MEng)--University of Pretoria, 2012. / Electrical, Electronic and Computer Engineering / unrestricted