Purpose: The purpose of our work is to develop a system for automatic contact tracing with the goal of identifying individuals who are most likely infected, even if we do not have direct diagnostic information on their health status. Control of the spread of respiratory pathogens (e.g. novel influenza viruses) in the population using vaccination is a challenging problem that requires quick identification of the infectious agent followed by large-scale production and administration of a vaccine. This takes a significant amount of time. A complementary approach to control transmission is contact tracing and quarantining, which are currently applied to sexually transmitted diseases (STDs). For STDs, identifying the contacts that might have led to disease transmission is relatively easy; however, for respiratory pathogens, the contacts that can lead to transmission include a huge number of face-to-face daily social interactions that are impossible to trace manually. Method: We developed a Bayesian network model to process context awareness proximity sensor information together with (possibly incomplete) diagnosis information to track the spread of disease in a population. Our model tracks real-time proximity contacts and can provide public health agencies with the probability of infection for each individual in the model. For testing our algorithm, we used a real-world mobile sensor dataset of 80 individuals, and we simulated an outbreak. Result: We ran several experiments where different sub-populations were ???infected??? and ???diagnosed.??? By using the contact information, our model was able to automatically identify individuals in the population who were likely to be infected even though they were not directly ???diagnosed??? with an illness. Conclusion: Automatic contact tracing for respiratory pathogens is a powerful idea, however we have identified several implementation challenges. The first challenge is scalability: we note that a contact tracing system with a hundred thousand individuals requires a Bayesian model with a billion nodes. Bayesian inference on models of this scale is an open problem and an active area of research. The second challenge is privacy protection: although the test data were collected in an academic setting, deploying any system will require appropriate safeguards for user privacy. Nonetheless, our work illustrates the potential for broader use of contact tracing for modelling and controlling disease transmission.

This study investigates how the Biblical teaching on death and the resurrection can provide the appropriate doctrinal challenge to the problem of the pervasive and persistent fear of death amongst the Luo people of Kenya. It therefore examines the Luo traditional beliefs and customs surrounding death in order to establish its contribution to the fear of death, even amongst some Luo Christians. A Biblical-theological study of death and the afterlife provides the doctrinal antidote necessary to rescue and transform a people under bondage to fear, thus outlining the basis for hope in a life beyond physical death through the doctrine of the resurrection. The research commences with a description of Luo traditional beliefs concerning death and dying, and outlines the related Luo customs in relation to their belief in the spirit-world. The contention is that these beliefs result in the fear of death, while the lack of Biblical understanding even amongst some Luo Christians has led to their ignorance of the Biblical teaching on death, and thus a loss of the assurance found in the resurrection of Christ. Death and the afterlife is carefully examined from a Biblical-theological perspective in order to demonstrate how the doctrine of the resurrection can function as a 'rescue doctrine' for those affected by the pervasive and persistent fear of death. The study also explores the assurance of triumph over death as an eschatological reality in keeping with Christ's work of redemption. Similarly, it is argued that triumph over evil and malevolent spirits is guaranteed. In closing, the study explores the power of the Gospel of the resurrected Christ to change lives and transform unbiblical practices and worldviews to conform to his will. It is the resurrected Christ alone who has the power to transform the moral and ethical values ingrained in any culture. / Thesis (M.A. (Dogmatics))--North-West University, Potchefstroom Campus, 2007.

The importance of health and quality health care in people’s daily lives is widely recognised. Physicians play a key role in delivering quality health care and improved patient outcomes. However, the evidence regarding physicians’ decision making and their perception of quality of health care delivery and its influencers is inconclusive. The overall aim of this thesis is to increase the understanding of quality in health care delivery and the factors that influence it from a physician’s perspective. This aim is fulfilled by conducting three interlinked research projects. The first research project comprises a systematic review of the literature that identifies the factors, contexts and theoretical underpinnings influencing physician decision making. The synthesis of 160 studies reveals two main categories of influencing factors. The first is ‘Contexts’, which refers to the set of circumstances or facts surrounding a particular event or situation. The second category is ‘Interventions’, which are the techniques, processes or actions introduced to create changes in how physicians make decisions while performing their clinical duties. Although extant literature provides ample evidence on factors influencing physician decision making the link to quality in health care is under researched. In the second research project, the author explores how physicians construct quality of health care delivery by means of investigating 162 clinical cases with 27 repertory gird interviews that yield eleven key constructs representing a classification of physicians’ conception of quality. The third research project examines physicians’ perceptions of enablers and barriers to quality in health care delivery, employing semi-structured interviews. Findings indicate that physician’s effort in delivering quality health care is largely influenced by factors affecting behavioural control (freedom to act). This research makes five contributions to knowledge. First, a novel classification of factors influencing physician decision making when prescribing is developed, providing new understanding of the link between these factors and quality of health care. Second, the systematic review shows an innovative application of factor analysis to structure the findings of a complex phenomenon. Third, the study presents a new conceptualisation of physicians’ construction of quality in health care. Fourth, the research provides a categorization of physicians’ perceived enablers and barriers to quality health care and the mechanisms by which they operate. Finally, this research develops a theoretically-grounded and empirically-informed conceptual model that incorporates three hitherto separate domains: agency, planned behaviour, and decision theories. This model provides a new integrated lens to better understand the complexities influencing quality in health care delivery. This study also makes two significant contributions to practice. First, the findings have helped initiate a transformation in the pharmaceutical industry’s business model, evolving from business-to-person to business-to-business. Second, the findings serve as a catalyst to drive organizational changes at Norway’s largest emergency hospital. As a result, a national debate was initiated, involving the Prime Minister and Minister of Health, on how hospital emergency care can best be provided at a national level.

The presence of Allophone students in French-language secondary schools in Ottawa is gradually increasing. While the politique d’aménagement linguistique (PAL) insists on the use of French within the school, one may begin to wonder which language Allophone students are speaking. French? English? Their native language(s)? This qualitative case study of four multilingual Allophone students explores their language repertoire use in relation to their desired linguistic representation, their linguistic proficiency in French, English, and their native language(s), and their perceptions of language prestige. The results indicate that students spoke a significant amount of English, some French (particularly with their teacher or Francophone classmates), and minimal amounts of their native language. Recommendations are suggested to increase the effectiveness of PAL within a Francophone minority context and to ensure that the policy’s objects are attained.

This thesis explores the field of context-aware information systems (CAIS). We present an approach called Compose, Learn, and Discover (CLD) to incorporate CAIS into the user daily workflow. The CLD approach is self-adjusting. It enables users to personalise the information views for different situations. The CAIS learns about the usage of the information views and recalls the right view in the right situation. We illustrate the CLD approach through an application in the health care field using the Clinical Document Architecture (CDA). In order to realise the CLD approach, we introduce Semantic Composition as a new paradigm to personalise information views. Semantic Composition leverages the type information in the domain model to simplify the user-interface composition process. We also introduce a pattern discovery mechanism that leverages data-mining algorithms to discover correlations between user information needs and different situations.

This thesis describes the design and implementation of the IPE, an interactive proof editor for first-order intuitionistic predicate calculus, developed at the University of Edinburgh during 1983-1986, by the author together with John Cartmell and Tatsuya Hagino. The IPE uses an attribute grammar to maintain the state of its proof tree as a context-sensitive structure. The interface allows free movement through the proof structure, and encourages a "proof-byexperimentation" approach, since no proof step is irrevocable. We describe how the IPE's proof rules can be derived from natural deduction rules for first-order intuitionistic logic, how these proof rules are encoded as an attribute grammar, and how the interface is constructed on top of the grammar. Further facilities for the manipulation of the IPE's proof structures are presented, including a notion of IPE-tactic for their automatic construction. We also describe an extension of the IPE to enable the construction and use of simply-structured collections of axioms and results, the main provision here being an interactive "theory browser" which looks for facts which match a selected problem.

Understanding the context of a person’s interaction with a place is important to enabling ubiquitous computing applications. The ability for mobile computing to provide information and services that are relevant to a user’s current location—which is central to the vision of ubiquitous computing—requires that the technologies be able to characterize the activities that a person may potentially perform in place, whatever this place may be. To support the user as she goes about her day, this ability to characterize the potential activities for a place must support work on a city scale. In this dissertation, we present a method to process place-specific community-authored content (e.g., Yelp.com reviews) to identify a set of the potential activities (articulated as verb-noun pairs) that a person can perform at a specific place and apply this method for places on a city scale. We validate the method by processing the place-specific reviews authored by community members of Yelp.com and show that the majority of the 40 most common verb-noun pairs are true activities that can be performed at the respective place; achieving an average mean precision of up to 79.3% and recall of up to 55.9%. We applied this method by developing a Web-service (the Activity Service) that automatically processes all the places reviewed for a city and provides structured access to the activity data that can be identified for the respective places. To validate that the place and activity data is useful and useable, we developed and evaluated two applications that are supported by the Activity Service: Opportunities Exist and Vocabulary Wallpaper. In addition to these applications, we conducted a design contest to identify other types of applications that can be supported by the Activity Service. Finally, we discuss limitations of the activity data and the Activity Service, and highlight future considerations.

Mobile applications can benefit from increased awareness of the device's context. Unfortunately, existing solutions for inferring context require special purpose sensors or beacons on the mobile devices or in the physical environment. This requirement significantly limits the deployment of these solutions. In this thesis, I argue that mobile devices can infer a substantial amount of their context by leveraging their existing wireless interfaces to monitor ambient radio sources, such as GSM cell towers or WiFi access points. I focus on two important problems in context-aware computing: localization of mobile devices and detecting proximity between mobile devices for authentication purposes. Specifically, I present an accurate localization system based on fingerprinting of GSM signals. I show that the key to more accurate GSM localization is the use of wide signal strength fingerprints that include readings from a large number of base stations. Next, I present a method that addresses the key drawback of fingerprint-based localization systems - the need to collect extensive measurements to train the system in every target environment. Finally, I show how radio environment sensing can be used to secure the communication of devices that come within close proximity. Removing the need for additional hardware on the mobile devices and in the physical environment renders the approach that I present amenable for widespread deployment.

Understanding the context of a person’s interaction with a place is important to enabling ubiquitous computing applications. The ability for mobile computing to provide information and services that are relevant to a user’s current location—which is central to the vision of ubiquitous computing—requires that the technologies be able to characterize the activities that a person may potentially perform in place, whatever this place may be. To support the user as she goes about her day, this ability to characterize the potential activities for a place must support work on a city scale. In this dissertation, we present a method to process place-specific community-authored content (e.g., Yelp.com reviews) to identify a set of the potential activities (articulated as verb-noun pairs) that a person can perform at a specific place and apply this method for places on a city scale. We validate the method by processing the place-specific reviews authored by community members of Yelp.com and show that the majority of the 40 most common verb-noun pairs are true activities that can be performed at the respective place; achieving an average mean precision of up to 79.3% and recall of up to 55.9%. We applied this method by developing a Web-service (the Activity Service) that automatically processes all the places reviewed for a city and provides structured access to the activity data that can be identified for the respective places. To validate that the place and activity data is useful and useable, we developed and evaluated two applications that are supported by the Activity Service: Opportunities Exist and Vocabulary Wallpaper. In addition to these applications, we conducted a design contest to identify other types of applications that can be supported by the Activity Service. Finally, we discuss limitations of the activity data and the Activity Service, and highlight future considerations.

There’s a widespread conviction in the norms of assertion literature that an agent’s asserting something false merits criticism. As Williamson puts it, asserting something false is likened to cheating at the game of assertion. Most writers on the topic have consequently proposed factive norms of assertion – ones on which truth is a necessary condition for the proper performance of an assertion. However, I argue that this view is mistaken. I suggest that we can illuminate the error by introducing a theoretical distinction between the norm of a practice and its goal. In light of this distinction, we can see that proponents of factive norms tend to mistake the goal of a practice for the norm. In making my case, I present an analogy between the norms and goals of placing wagers and the norms and goals of assertion. One may place a bet and lose without being subject to criticism, while one may win and be worthy of criticism. Whether one wins or loses is irrelevant to the normative evaluation of a bet. What is relevant is whether the bet maximizes the bettor's expected value, which is a function of what might be lost, what might be gained, and how likely those prospects are, given the bettor's evidence. Similarly, I argue, whether one's assertion is true or false is not strictly relevant to the normative evaluation of an assertion. What is relevant is whether the speaker has adequate supporting reasons for the assertion, and that the necessary conventional and pragmatic features are present. However, context will determine what count as supportive reasons for a given proposition, what counts as relevant, and what count as conventional and pragmatic elements possessing that relevance. My proposed norm, the Supportive Reasons Norm, is thus sensitive to the context of assertion and shifts from context to context.