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Auflistung nach Autor:in "George, Ceenu"

1 - 3 von 3
  • Konferenzbeitrag
    Design Considerations for Usable Authentication in Smart Homes
    (Mensch und Computer 2021 - Tagungsband, 2021) Prange, Sarah; George, Ceenu; Alt, Florian
    Smart home devices are on the rise. To provide their rich variety of features, they collect, store and process a considerable amount of (potentially sensitive) user data. However, authentication mechanisms on such devices a) have limited usability or b) are nonexisting. To close this gap, we investigated, on one hand, users’ perspectives towards potential privacy and security risks as well as how they imagine usable authentication mechanisms in future smart homes. On the other hand, we considered security experts’ perspectives on authentication for smart homes. In particular, we conducted semi-structured interviews (N=20) with potential smart home users using the story completion method and a focus group with security experts (N=10). We found what kind of devices users would choose and why, potential challenges regarding privacy and security, and potential solutions. We discussed and verified these with security experts. We derive and reflect on a set of design implications for usable authentication mechanisms for smart homes and suggest directions for future research. Our work can assist designers and practitioners when implementing appropriate security mechanisms for smart homes.
  • Konferenzbeitrag
    Konzepte und Schnittstellen für eine Nahtlose Interaktion zwischen Virtueller und Physischer Realität
    (Ausgezeichnete Informatikdissertationen 2020, 2021) George, Ceenu
    Virtual Reality (VR, Virtuelle Realität) ermöglicht es Benutzern, realitätsnahe Modelle von Produkten zu erstellen und eine immersive soziale Interaktion mit entfernten Kollegen zu erleben. VR nutzt unsere visuelle Dominanz, um diese Erfahrungen zu vermitteln, und versucht Nutzer davon zu überzeugen, dass sie sich in einer anderen Realität befinden. Während ihr Bewusstsein jedoch in VR präsent ist, befindet sich ihr Körper in der physische Realität (PR). Da der Nutzer die PR nicht sehen kann, bringt dies erhebliche Unsicherheiten in die Interaktion. In dieser Arbeit gehe ich auf diese Unsicherheit ein, indem ich Konzepte und Schnittstellen entwickle, die es dem Nutzer ermöglichen, in VR zu bleiben und gleichzeitig ein Bewusstsein für die PR zu behalten. Sie behalten dieses Bewusstsein bei, ohne das Head-mounted-display (HMD) abnehmen zu müssen. Ich bezeichne das als nahtlose Interaktion mit der PR. Die übergreifende Forschungsvision dieser Arbeit ist daher, die Trennung zwischen der virtuellen und der physischen Realität zu reduzieren.
  • Dissertation
    Virtual reality interfaces for seamless interaction with the physical reality
    (2020) George, Ceenu
    In recent years head-mounted displays (HMDs) for virtual reality (VR) have made the transition from research to consumer product, and are increasingly used for productive purposes such as 3D modeling in the automotive industry and teleconferencing. VR allows users to create and experience real-world like models of products; and enables users to have an immersive social interaction with distant colleagues. These solutions are a promising alternative to physical prototypes and meetings, as they require less investment in time and material. VR uses our visual dominance to deliver these experiences, making users believe that they are in another reality. However, while their mind is present in VR their body is in the physical reality. From the user’s perspective, this brings considerable uncertainty to the interaction. Currently, they are forced to take off their HMD in order to, for example, see who is observing them and to understand whether their physical integrity is at risk. This disrupts their interaction in VR, leading to a loss of presence – a main quality measure for the success of VR experiences. In this thesis, I address this uncertainty by developing interfaces that enable users to stay in VR while supporting their awareness of the physical reality. They maintain this awareness without having to take off the headset – which I refer to as seamless interaction with the physical reality. The overarching research vision that guides this thesis is, therefore, to reduce this disconnect between the virtual and physical reality. My research is motivated by a preliminary exploration of user uncertainty towards using VR in co-located, public places. This exploration revealed three main foci: (a) security and privacy, (b) communication with physical collaborators, and (c) managing presence in both the physical and virtual reality. Each theme represents a section in my dissertation, in which I identify central challenges and give directions towards overcoming them as have emerged from the work presented here. First, I investigate security and privacy in co-located situations by revealing to what extent bystanders are able to observe general tasks. In this context, I explicitly investigate the security considerations of authentication mechanisms. I review how existing authentication mechanisms can be transferred to VR and present novel approaches that are more usable and secure than existing solutions from prior work. Second, to support communication between VR users and physical collaborators, I add to the field design implications for VR interactions that enable observers to choose opportune moments to interrupt HMD users. Moreover, I contribute methods for displaying interruptions in VR and discuss their effect on presence and performance. I also found that different virtual presentations of co-located collaborators have an effect on social presence, performance and trust. Third, I close my thesis by investigating methods to manage presence in both the physical and virtual realities. I propose systems and interfaces for transitioning between them that empower users to decide how much they want to be aware of the other reality. Finally, I discuss the opportunity to systematically allocate senses to these two realities: the visual one for VR and the auditory and haptic one for the physical reality. Moreover, I provide specific design guidelines on how to use these findings to alert VR users about physical borders and obstacles.