Traditionally, security has been conceptualized as rules, locks, and passwords. More recently, security research has explored how people interact in secure (or insecure) ways in part of a larger socio-technical system. Socio-technical systems are comprised of people, technology, relationships, and interactions that work together to create safe praxis. Because information systems are not just technical, but also social, the scope of privacy and security concerns must include social and technical factors. Clearly, computer security is enhanced by developments in the technical arena, where researchers are building ever more secure and robust systems to guard the privacy and confidentiality of information. However, when the definition of security is broadened to encompass both human and technical mechanisms, how security is managed with and through the day-to-day social work practices becomes increasingly important. In this dissertation I focus on how sensitive information is collaboratively managed in socio-technical systems by examining two domains: childcare centers and physicians' offices. In childcare centers, workers manage the enrolled children and also the enrolled child's personal information. In physicians' offices, workers manage the patients' health along with the patients' health information. My dissertation presents results from interviews and observations of these locations. The data collected consists of observation notes, interview transcriptions, pictures, and forms. The researchers identified breakdowns related to security and privacy. Using Activity Theory to first structure, categorize, and analyze the observed breakdowns, I used phenomenological methods to understand the context and experience of security and privacy. The outcomes from this work are three themes, along with corresponding future scenarios. The themes discussed are security embodiment, communities of security, and zones of ambiguity. Those themes extend the literature in the areas of usable security, human-computer interaction, and trust. The presentation will use future scenarios to examine the complexity of developing secure systems for the real world. / Ph. D.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / The surprise failure of two NASA Space Shuttles and the premature failures of satellite subsystem equipment on NASA satellites are motivating NASA to adopt an engineering discipline that uses telemetry specifically developed for preventing surprise equipment failures. The NASA Orion spacecraft is an Apollo module-like capsule planned to replace the NASA Space Shuttle reusable launch vehicle for getting astronauts to space and return to the earth safely as well as a crew escape vehicle stored at the ISS. To do so, NASA is adopting a non-Markov reliability paradigm for measuring equipment life based on the prognostic and health management program on the Air Force F-35 Joint Strike Fighter. The decision is based on the results from the prognostic analysis completed on the Space Shuttle Challenger and Columbia that identified the information that was present but was ignored for a variety of reasons. The goal of a PHM is to produce equipment that will not fail prematurely. It includes using predictive algorithms to measure equipment usable life. Equipment with transient behavior caused from accelerated of parts will fail prematurely with 100% certainty. For many decades, it was believed that test equipment and software used to in testing and noise from communications equipment were the cause of most transient behavior. With the processing speed of today's processors, transient behavior is caused from at least one part suffering from accelerated aging. Transient behavior is illustrated in equipment telemetry in a prognostic analysis. Telemetry is equipment performance information and equipment performance has been used to increase reliability, but performance is unrelated to equipment remaining usable life and so equipment should be failing prematurely. A PHM requires equipment telemetry for analysis and so analog telemetry will be available from all Orion avionics equipment. Replacing equipment with a measured remaining usable life of less than one year will stop the premature and surprise equipment failures from occurring during future manned and unmanned space missions.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Satellite and launch vehicles continues to suffer from catastrophic infant mortality failures. NASA now requires satellite suppliers to provide on-orbit satellite delivery and a free satellite and launch vehicle in the event of a catastrophic infant mortality failure. A high infant mortality failure rate demonstrates that the factory acceptance test program alone is inadequate for producing 100% reliability space vehicle equipment. This inadequacy is caused from personnel only measuring equipment performance during ATP and performance is unrelated to reliability. Prognostic technology uses pro-active diagnostics, active reasoning and proprietary algorithms that illustrate deterministic data for prognosticians to identify piece-parts, components and assemblies that will fail within the first year of use allowing this equipment to be repaired or replaced while still on the ground. Prognostic technology prevents equipment failures and so is pro-active. Adding prognostic technology will identify all unreliable equipment prior to shipment to the launch pad producing 100% reliable equipment and will eliminate launch failures, launch pad delays, on-orbit infant mortalities, surprise in-orbit failures. Moving to the 100% reliable equipment extends on-orbit equipment usable life.

ITC/USA 2012 Conference Proceedings / The Forty-Eighth Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2012 / Town and Country Resort & Convention Center, San Diego, California / The surprise failure of two NASA Space Shuttles and the premature failures of satellite subsystem equipment on NASA satellites are motivating NASA to adopt an engineering discipline specifically developed for preventing surprise equipment failures. The NASA Orion spacecraft is an Apollo module-like capsule planned to replace the NASA Space Shuttle reusable launch vehicle for getting astronauts to space and return to the earth safely as well as a crew escape vehicle stored at the ISS. To do so, NASA is adopting a non-Markov reliability paradigm for measuring equipment life based on the prognostic and health management program on the Air Force F-35 Joint Strike Fighter. The decision is based on the results from the prognostic analysis completed on the Space Shuttle Challenger and Columbia that identified the information that was present but was ignored for a variety of reasons prior to both accidents. The goal of a PHM is to produce equipment that will not fail prematurely and includes using predictive algorithms to measure equipment usable life. Equipment with transient behavior, missed by engineering analysis is caused from accelerated of parts will fail prematurely with 100% certainty. With the processing speed of today's processors, transient behavior is caused from at least one part suffering from accelerated aging. Transient behavior is illustrated in equipment telemetry in a prognostic analysis but not in an engineering analysis. Telemetry is equipment performance information and equipment performance has been used to increase reliability, but performance is unrelated to equipment remaining usable life and so equipment should be failing prematurely. A PHM requires equipment telemetry for analysis and so analog telemetry will be available from all Orion avionics equipment. Replacing equipment with a measured remaining usable life of less than one year will stop the premature and surprise equipment failures from occurring during future manned and unmanned space missions.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / This paper addresses the research conducted at U.C. Berkeley Space Sciences Laboratory, Center for Extreme Ultra Violet Astrophysics between 1994 and 1995 on the NASA EUVE ion-orbit satellite. It includes the results from conducting a scientific analysis called a prognostic analysis completed on all satellite subsystem equipment. A prognostic analysis uses equipment analog telemetry to measure equipment remaining usable life. The analysis relates equipment transient behavior, often referred to as "cannot duplicates" in a variety of industries caused from accelerated aging to the equipment end-of-life with certainty. The analysis was confirmed by using proprietary, pattern recognition software by Lockheed Martin personnel Lockheed Martin personnel completed an exploration into the application of statistical pattern recognition methods to identify the behavior caused from accelerated aging that experts in probability reliability analysis claims cannot exist. Both visual and statistical methods were successful in detecting suspect accelerated aging and this behavior was related to equipment end of life with certainty. The long-term objective of this research was to confirm that satellite subsystem equipment failures could be predicted so that satellite subsystem and payload engineering personnel could be allocated for only the time that equipment failures were predicted to occur, lowering the cost of mission operations. This research concluded that satellite subsystem equipment remaining usable life could be measured and equipment failures could be predicted with certainty so that engineering support for mission operations could be greatly reduced.

People engage with multiple online services and carry out a range of different digital transactions with these services. Registering an account, sharing content in social networks, or requesting products or services online are a few examples of such digital transactions. With every transaction, people take decisions and make disclosures of personal data. Despite the possible benefits of collecting data about a person or a group of people, massive collection and aggregation of personal data carries a series of privacy and security implications which can ultimately result in a threat to people's dignity, their finances, and many other aspects of their lives. For this reason, privacy and transparency enhancing technologies are being developed to help people protect their privacy and personal data online. However, some of these technologies are usually hard to understand, difficult to use, and get in the way of people's momentary goals. The objective of this thesis is to explore, and iteratively improve, the usability and user experience provided by novel privacy and transparency technologies. To this end, it compiles a series of case studies that address identified issues of usable privacy and transparency at four stages of a digital transaction, namely the information, agreement, fulfilment and after-sales stages. These studies contribute with a better understanding of the human-factors and design requirements that are necessary for creating user-friendly tools that can help people to protect their privacy and to control their personal information on the Internet. / People engage with multiple online services and carry out a range of different digital transactions with these services. Registering an account, sharing content in social networks, or requesting products or services online are a few examples of such digital transactions. With every transaction, people take decisions and make disclosures of personal data. Despite the possible benefits of collecting data about a person or a group of people, massive collection and aggregation of personal data carries a series of privacy and security implications which can ultimately result in a threat to people's dignity, their finances, and many other aspects of their lives. For this reason, privacy and transparency enhancing technologies are being developed to help people protect their privacy and personal data online. However, some of these technologies are usually hard to understand, difficult to use, and get in the way of people's momentary goals. The objective of this thesis is to explore, and iteratively improve, the usability and user experience provided by novel privacy and transparency technologies. To this end, it compiles a series of case studies that address identified issues of usable privacy and transparency at four stages of a digital transaction, namely the information, agreement, fulfilment and after-sales stages. These studies contribute with a better understanding of the human-factors and design requirements that are necessary for creating user-friendly tools that can help people to protect their privacy and to control their personal information on the Internet.

The research reported in this thesis focuses on developing a framework for game design to protect computer users against phishing attacks. A comprehensive literature review was conducted to understand the research domain, support the proposed research work and identify the research gap to fulfil the contribution to knowledge. Two studies and one theoretical design were carried out to achieve the aim of this research reported in this thesis. A quantitative approach was used in the first study while engaging both quantitative and qualitative approaches in the second study. The first study reported in this thesis was focused to investigate the key elements that should be addressed in the game design framework to avoid phishing attacks. The proposed game design framework was aimed to enhance the user avoidance behaviour through motivation to thwart phishing attack. The results of this study revealed that perceived threat, safeguard effectiveness, safeguard cost, self-efficacy, perceived severity and perceived susceptibility elements should be incorporated into the game design framework for computer users to avoid phishing attacks through their motivation. The theoretical design approach was focused on designing a mobile game to educate computer users against phishing attacks. The elements of the framework were addressed in the mobile game design context. The main objective of the proposed mobile game design was to teach users how to identify phishing website addresses (URLs), which is one of many ways of identifying a phishing attack. The mobile game prototype was developed using MIT App inventor emulator. In the second study, the formulated game design framework was evaluated through the deployed mobile game prototype on a HTC One X touch screen smart phone. Then a discussion is reported in this thesis investigating the effectiveness of the developed mobile game prototype compared to traditional online learning to thwart phishing threats. Finally, the research reported in this thesis found that the mobile game is somewhat effective in enhancing the user’s phishing awareness. It also revealed that the participants who played the mobile game were better able to identify fraudulent websites compared to the participants who read the website without any training. Therefore, the research reported in this thesis determined that perceived threat, safeguard effectiveness, safeguard cost, self-efficacy, perceived threat and perceived susceptibility elements have a significant impact on avoidance behaviour through motivation to thwart phishing attacks as addressed in the game design framework.

Student Number : 0105159R - MSc(Eng) Dissertation - School of Electrical and Information Engineering - Faculty of Engineering and the Built Environment / This dissertation presents the design of a re-usable rocket for use in triggered-lightning experiments. It is intended that the rocket will tow a thin wire to sufficient height so that the lightning mechanism will attach onto the wire and follow it to ground. The rocket design is inherently safe as it does not use explosive materials for its propulsion system, and hence conforms to South African explosive legislation. The designed rocket consists of a hybrid motor, which uses a solid combustion chamber and liquid oxidiser rather than solid motors which use a single solid fuel or a liquid motor which uses two liquid propellants. The mechanical performance of the oxidiser stage is critical in containing the pressurised oxidiser and regulating the flow of the oxidiser into the combustion chamber. The design of the combustion chamber and the rate at which the solid material burns is key to the generation of the pressure which is expelled through the nozzle to produce thrust. The design of the nozzle is covered in which the material from which it is made must withstand temperatures in excess of 1600 ◦C. The entire system was modelled to calculate the parameters of the various subsystems. The simulation study shows that the rocket will be able to reach 1 km with a complete section of wire towed behind it. A cost analysis, against other commercial rocket systems, was performed. The analysis concludes from the total cost of ownership that it is significantly cheaper to operate the designed rocket, over the course of the experiment, than other rocket systems.

Transparency of personal data processing is enforced by most Western privacy laws, including the new General Data Protection Regulation (GDPR) which will be effective from May 2018. The GDPR specifies that personal data shall be processed lawfully, fairly, and in a transparent manner. It strengthens people's rights for both ex-ante and ex-post transparency and intervenability. Equally important is the strict legal requirements for informed consent established by the GDPR. On the other hand, the legal privacy principles have Human-Computer Interaction (HCI) implications. People should comprehend the principles, be aware of when the principles may be used, and be able to use them. Transparent information about personal data processing should be concise, intelligible, and provided in an easily accessible form, pursuant to the GDPR. Nonetheless, the answer to the question about how HCI implications can be addressed depends on the attempts to decrease the gap between legal and user-centric transparency, intervenability, and consent. Enhancing individuals' control in a usable way helps people to be aware of the flow of their personal information, control their data, make informed decisions, and finally preserve their privacy. The objective of this thesis is to propose usable tools and solutions, to enhance people's control and enforce legal privacy principles, especially transparency, intervenability, and informed consent. To achieve the goal of the thesis, different ways to improve ex-ante transparency and informed consent are investigated by designing and testing new solutions to make effective consent forms. Moreover, ex-post transparency and intervenability are improved by designing a transparency enhancing tool and investigating users' perceptions of data portability and transparency in the tool. The results of this thesis contribute to the body of knowledge by mapping legal privacy principles to HCI solutions, unveiling HCI problems and answers when aiming for legal compliance, and proposing effective designs to obtain informed consent. / The new General Data Protection Regulation (GDPR) strengthens people’s rights for transparency, intervenability, and consent. The legal privacy principles have Human-Computer Interaction (HCI) implications. Besides aiming for legal compliance, it is of paramount importance to investigate how to provide individuals with usable and user-centric transparency, intervenability, and consent. The objective of this thesis is to propose usable tools and solutions, to enhance people's control and enforce legal privacy principles, especially transparency, intervenability, and informed consent. To achieve the goal of the thesis, different ways to improve ex-ante transparency and informed consent are investigated by designing and testing new solutions to make effective consent forms. Moreover, ex-post transparency and intervenability are improved by designing a transparency enhancing tool and investigating users' perceptions of data portability and transparency in the tool. The results of this thesis contribute to the body of knowledge by mapping legal privacy principles to HCI solutions, unveiling HCI problems and answers when aiming for legal compliance, and proposing effective designs to obtain informed consent. / <p>The 3. article was in manuscript form at the time of the licentiate defense: Karegar, F. / User Evaluations of an App Interface for Cloud-based Identity Management / / Manuskript (preprint)</p>

Objective: This study investigates the application of aesthetic principles to designed objects with which we interact, specifically looking at the impact of perceived function of the objects on perceptions of visual appeal. Background: Previous studies have demonstrated that a product’s judged beauty or visual appeal is related to perceptions of its usability. Arguments have been put forward for both directions of causality leading to “what is beautiful is usable” and “what is usable is beautiful” hypotheses. Explanations for the relationship between usability and beauty judgments include stereotype effects, ecological explanations, and cognitive processing viewpoints. The current studies contribute to this debate by manipulating usability and aesthetic principles independently to determine whether well-established aesthetic principles are contingent on perceived function. Method: 248 participants were recruited for two experiments. In Experiment 1, participants viewed sixteen illustrations that varied in ways that frequently increase the beauty of objects (i.e., basic principles such as symmetry, balanced massing, curvature, and prototypicality) and rated their degree of visual appeal. In Experiment 2, participants rated the appeal of the same stimuli as in Experiment 1 but were primed by instructions describing the illustrations as either alternative designs for microwave control panels or designs of building façades. Results: Strong support for the aesthetic principles of symmetry and spatial massing, but not curvature, were found in both experiments. Participants generally preferred stimuli that were symmetrical and evenly massed (i.e., "balanced"). Additionally, the manipulation of a functional prime significantly interacted with several aesthetic principles that relate to the match between the supplied prime and the prototypicality of the stimulus for the primed class of objects. Conclusions: Aesthetic principles of symmetry and spatial massing can be considered very potent ways to influence a user’s degree of perceived visual appeal that are resistant to specific use cases or situations. Other principles, such as curvature preferences, seem to be limited by the prototypicality of curvature for a primed class of objects. So when considering whether “what is beautiful is usable” or “what is usable is beautiful," the results from the current study demonstrate that it may be more appropriate to say "what is familiar is beautiful."