Context-aware systems can dynamically adapt to user situations to provide smarter services. In general, context refers to the information that can be used to characterize these situations, and context models are deployed to specify contextual information described in context-aware systems. However, even though user context is highly dynamic, existing context models either focus on modeling static views of context or lack appropriate design abstractions to deal with dynamic aspects and interactions involving contextual elements such location, time, user roles, social relationships, and changing preferences. Moreover, virtual environments have not been modelled by most of the existing context models even though online interaction is very common and popular. This thesis presents a dynamic user-centric context model that can be used to model the aspects of context-aware systems that are subject to frequent change. Four case studies are proposed to illustrate the applicability of the approach taken by this thesis, and they are in the domains of mobile e-healthcare, mobile commerce, mobile tourism, and mobile augmented reality gaming. Benefits of the proposed model include avoiding the development of context-aware systems from scratch, enabling future use of model-driven approaches, and reducing implementation effort.

Evolving smart infrastructures requires both content distribution as well as event notification and processing support. Content Centric Networking (CCN), built around named data, is a clean slate network architecture for supporting future applications. Due to its focus on content distribution, CCN does not inherently support Publish-Subscribe event notification, a fundamental building block in computer mediated systems and a critical requirement for smart infrastructure applications. While semantics of content distribution and event notification require different support systems from the underlying network infrastructure, content distribution and event notification can still be united by leveraging similarities in the routing infrastructure. Our Extended-CCN architecture(X-CCN) realizes this to provide lightweight content based pub-sub service at the network layer, which is used to provide advanced publish/subscribe services at higher layers. Light weight content based pub-sub and CCN communication at network layer along with advanced publish/subscribe together are presented as data fabric for the smart infrastructures applications.

Inclusive design is a concept intended to promote the development of products and environments equally usable by all users, irrespective of their age or ability. This research focuses on developing a method to derive heuristics for inclusive design. The research applies the actionfunction diagram to model the interaction between a user and a product, design difference classification to compare a typical product with its inclusive counterpart, graph theory to mathematically represent the comparison relations, and graph data mining to extract the design heuristics. The goal of this research is to formalize and automate the inclusive-design heuristics generation process. The rule generation allows statistical mining of the design guidelines from existing inclusive products. Formalization results show that, the rate of rule generation decreases as more products are added to the dataset. The automated method is particularly helpful in the developmental stages of graph mining applications for product design. The graph mining technique has capability for graph grammar induction, which is extended here to automate the generation of engineering grammars. In general, graph mining can be applied to extract design heuristics from any discrete and relational design data that can be represented as graphs. Concept generation studies are conducted to validate the heuristics derived in this research for inclusive product design. In addition, an inclusivity rating is created and verified to evaluate the inclusiveness of the conceptual ideas. Finally, appreciation and awareness about inclusive design is important in an engineering design course, hence, a module is compiled to teach inclusive design methods in a capstone design course. The results of the exploratory study and validation show that there is problem dependency in the application of the representation scheme. It cannot be stated with certainty at this point if the representation scheme is helpful for designing consumer products, where only the activities related to the upper body are involved. However, self-reported feedback indicates that the teaching module is effective in increasing the awareness and confidence about inclusive design.

Developing high quality software is of eminent importance to keep the existing customers satisfied and to remain competitive. One of the most important software quality characteristics is performance, which defines how fast and/or efficiently a software can perform its operation. While several studies have shown that field problems are often due to performance issues instead of feature bugs, prior research typically treats all bugs as similar when studying various aspects of software quality (e.g., predicting the time to fix a bug) or focused on other types of bug (e.g., security bugs). There is little work that studies performance bugs. In this thesis, we perform an empirical study to quantitatively and qualitatively examine performance bugs in the Mozilla Firefox and Google Chrome web browser projects in order to find out if performance bugs are really different from other bugs in practice and to understand the rationale behind those differences. In our quantitative study, we find that performance bugs of the Firefox project take longer time to fix, are fixed by more experienced developers, and require changes to more lines of code. We also study performance bugs relative to security bugs, since security bugs have been extensively studied separately in the past. We find that security bugs are re-opened and tossed more often, are fixed and triaged faster, are fixed by more experienced developers, and are assigned more number of developers in the Firefox project. Google Chrome project also shows different quantitative characteristics between performance and non-performance bugs and from the Firefox project. Based on our quantitative results, we look at that data from a qualitative point of view. As one of our most interesting observation, we find that end-users are often frustrated with performance problems and often threaten to switch to competing software products. To better understand, the rationale for some users being very frustrated (even threatening to switch product) even though most systems are well tested, we performed an additional study. In this final study, we explore a global perspective vs a user centric perspective of analyzing performance data. We find that a user-centric perspective might lead to a small number of users with considerably poor performance while the global perspective might show good or same performance across releases. The results of our studies show that performance bugs are different and should be studied separately in large scale software systems to improve the quality assurance processes related to software performance. / Thesis (Master, Computing) -- Queen's University, 2012-04-30 01:28:22.623

<p>The aim of this study is to illustrate, adapt and develop methods of survival analysis in analysing and estimating customer survival time in subscription-based businesses. Two particular objectives are studied. The rst objective is to redene the existing survival analysis techniques in business terms and to discuss their uses in order to understand various issues related to the customer-rm relationship.</p>

Content Centric Networking (CCN) is a novel networking architecture in which communication is resolved based on names, or descriptions of the data transferred instead of addresses of the end-hosts. While CCN demonstrates many promising potentials, its current implementation suffers from severe performance limitations. In this thesis we study the performance and analyze the bottleneck of the existing CCN prototype. Based on the analysis, a variety of design alternatives are proposed for realizing high performance content centric networking over virtual infrastructure. Preliminary implementations for two of the approaches are developed and evaluated on Smart Applications on Virtual Infrastructure (SAVI) testbed. The evaluation results demonstrate that our design is capable of providing scalable content centric routing solution beyond 1Gbps throughput under realistic traffic load.

Content Centric Networking (CCN) is a novel networking architecture in which communication is resolved based on names, or descriptions of the data transferred instead of addresses of the end-hosts. While CCN demonstrates many promising potentials, its current implementation suffers from severe performance limitations. In this thesis we study the performance and analyze the bottleneck of the existing CCN prototype. Based on the analysis, a variety of design alternatives are proposed for realizing high performance content centric networking over virtual infrastructure. Preliminary implementations for two of the approaches are developed and evaluated on Smart Applications on Virtual Infrastructure (SAVI) testbed. The evaluation results demonstrate that our design is capable of providing scalable content centric routing solution beyond 1Gbps throughput under realistic traffic load.

Evolving smart infrastructures requires both content distribution as well as event notification and processing support. Content Centric Networking (CCN), built around named data, is a clean slate network architecture for supporting future applications. Due to its focus on content distribution, CCN does not inherently support Publish-Subscribe event notification, a fundamental building block in computer mediated systems and a critical requirement for smart infrastructure applications. While semantics of content distribution and event notification require different support systems from the underlying network infrastructure, content distribution and event notification can still be united by leveraging similarities in the routing infrastructure. Our Extended-CCN architecture(X-CCN) realizes this to provide lightweight content based pub-sub service at the network layer, which is used to provide advanced publish/subscribe services at higher layers. Light weight content based pub-sub and CCN communication at network layer along with advanced publish/subscribe together are presented as data fabric for the smart infrastructures applications.

Recent global and structural transformations, a West-centric development agenda and the triumph of neoliberal politics have led to destructive consequences for many local communities and individual life chances. The global dominance of the West-centric development agenda, with its roots in the colonial past, has created uneven developments and an unjust world in which Western countries continue to gain advantages and increase their prosperity. Although a minority elite in many non-Western countries share the same interests as Western countries and their global organs, the majority of people in these countries are suffering from increasing socioeconomic inequalities. As a result of the dogmatic belief in a singular and West-centric modernity and its practices, many problems are considered to be the result of non-Western countries’ inabilities to complete the project of modernity in accordance with Western blueprints. This has also influenced social work as a global and modern profession. Social problems are often individualised and the reasons behind many inequalities are increasingly related to non-Western people’s individual shortcomings and traditional cultural backgrounds. In Western and non-Western countries equally are the neoliberal structural and institutional transformations ignored and social problems of individuals and families defined as a matter of wrong and deviant actions and choices. The main objective of the dissertation, which is constituted of four articles and an overall introduction and summary, is to examine the consequences of recent neoliberal globalisation based on the belief in a single and West-centric modernity and development agenda and their consequences for social work facing increasing global inequalities. The following research questions have guided the work: ‘How can social work play an effective role in combating social problems and otherisation, marginalisation and increasing inequalities in a globalised world?’, ‘How does the global development agenda function within the local arenas of social work?’, ‘Are development projects improving people’s life chances in local communities in non-Western countries?’, ‘How informed and responsive are social workers towards the global context of local problems?’ The work is based on a qualitative design using qualitative content analysis for analysing data collected through interviews, participant observations and official documents. The results show that irrespective of where and in which context social problems are appearing, since local problems often have global roots, a global perspective to local problems should be included in every practices of social work in order to develop new methods of practices in an increasingly globalised field of work. Destruction of local communities, forced migration from non-Western countries, and marginalisation of people with immigrant background in Western countries should not be considered only as local problems, but also as problems with their roots in global structural inequalities which reproduces global social problems with local consequences. It is argued that social work should consider the dilemmas and problems connected to the taken for granted West-centric theories, understandings and practices of social work in order to develop new methods of practices for combating social problems, marginalisation and increasing inequalities in a globalised world. Such a position includes practicing multilevel social work, social work in global alliances beyond the division of East and West, and mobilisation against neoliberalism and the retreat of the welfare state. This requires critical standpoints against the relationship between the global context of the neoliberal ideology and practices in a Western-dominated and postcolonial world and the daily practices of social work. / Localised Globalities and Social Work: Contemporary Challenges

The main aim of the study was to determine which measurement tool, existing or adapted, would be able to determine the levels of customer centricity within the sales channels of a specific organisation, operating in the South African financial industry. A literary study showed that in order to determine the levels of customer centricity, customer experience should be measured. Six questionnaires were administered, namely, EXQ, NPS, CES, Customer satisfaction, Word-of-Mouth and Behavioural loyalty intention. The data showed a statistical significance and a positive relationship between all the constructs within all the questionnaires except with that of CES. / MBA, North-West University, Potchefstroom Campus, 2014