The cognitive mapping of virtual space

Not availabl

Quasi-Periodic Oscillations from Magnetorotational Turbulence

Quasi-periodic oscillations (QPOs) in the X-ray lightcurves of accreting neutron star and black hole binaries have been widely interpreted as being due to standing wave modes in accretion disks. These disks are thought to be highly turbulent due to the magnetorotational instability (MRI). We study wave excitation by MRI turbulence in the shearing box geometry. We demonstrate that axisymmetric sound waves and radial epicyclic motions driven by MRI turbulence give rise to narrow, distinct peaks in the temporal power spectrum. Inertial waves, on the other hand, do not give rise to distinct peaks which rise significantly above the continuum noise spectrum set by MRI turbulence, even when the fluid motions are projected onto the eigenfunctions of the modes. This is a serious problem for QPO models based on inertial waves.Comment: 4 pages, 2 figures. submitted to ap

Being-with: a study of familiarity

How people learn to use an interactive device has always been an important field of research in human-computer interaction (HCI). The theoretical bases of which have ranged from the traditional cognitive perspectives through situated learning to collectivist - social perspectives. Each of these has treated learning to use interactive devices in a typical dualistic manner with a clear distinction between ''man and machine''. However, in addition to simply using interactive technologies we also co-exist with them, a relationship which might be called being-with. For many of us, interactive technology has always been there (we are born into a world replete with it) and we have a deep familiarity with it. Familiarity, according to Heidegger, is non-dualistic; it is a fact of our existence, of our worldliness; it is one of the primary ways in which we relate to the world, and offers an alternate basis for thinking about how we learn to use technology. An empirical study of familiarity is presented involving a group of seniors learning to use a personal computer and the services it provides. The analysis of the resultant substantial body of interview and discussion group data lead to the conclusion that to become familiar with technology is to integrate it into one's everyday life - an everyday life which is correspondingly reconfigured. Specifically, learning to use these technologies is better seen as changing the practices of everyday life to accommodate them. This dimension of being-with potentially has significant consequences for very many aspects of HCI. So, in addition to designing for ease of use; designing for experience perhaps we should now add designing for being-with

Triangulation in practice.

Triangulation is the means by which an alternate perspective is used to validate, challenge or extend existing findings. It is frequently used when the field of study is difficult, demanding or contentious and presence research meets all of these criteria. We distinguish between the use of hard and soft triangulation-the former emphasising the challenging of findings, the latter being more confirmatory in character. Having reviewed a substantial number of presence papers, we conclude that strong triangulation is not widely used while soft triangulation is routinely employed. We demonstrate the usefulness of hard triangulation by contrasting an ontological analysis of in-ness with an empirical study of (computer) game playing. We conclude that presence research would be well served by the wider use of hard triangulation and for the reporting of anomalous and ill-fitting results

Towards an account of intuitiveness

Intuitive systems are usable systems. Design guidelines advocate intuitiveness and vendors claim it - but what does it mean for a user interface, interactive system, or device to be intuitive? A review of the use of the term 'intuitive' indicates that it has two distinct but overlapping meanings, namely intuitiveness based on familiarity and intuitiveness reflecting our embodiment (and frequently both). While everyday usage indicates that familiarity means either a passing acquaintance or an intimacy with something or someone, it will be concluded that familiarity might best be equated with 'know-how', which in turn is based on a deep, often tacit, understanding. The intuitive nature of tangible user interfaces will in turn be attributed to embodiment rather than tangibility per se. Merleau-Ponty writes that it is through our bodies that we 'prehend' the world. A number of disciplines now regard action-perception as so closely coupled that they are better considered as a dyad rather than separately. A modified treatment of action-perception coupling is proposed, with familiarity providing an epistemic core, as the basis of intuitiveness

Emotional and aesthetic attachment to digital artefacts

We report a pair of repertory grid studies that explore the attachment people have for digital and nondigitalartefacts.In the first study we found no clear distinctions between emotional attachment to digital and nondigitalartefacts: people are attached to their mobile phones in much the same way as to a childhoodteddy bear. There was also evidence that attachment and the physical availability or proximity of theartefact were associated.In the second study we examined the aesthetics of attachment to digital and non-digital artefacts.Again the proximity or availability of the artefacts appeared to be important. Items that were carriedabout or worn, such as wristwatches and laptops, were closely associated while TVs and gamesconsoles were not.In all, there does not appear to be any qualitative differences between the attachment people have fordigital and non-digital artefacts. Nor do aesthetics appear to play a part in this attachment. Howeverthe physical proximity of these artefacts is strongly associated with our (inward) feelings ofattachment to them, while we can also recognise the importance of this relationship to how we(outwardly) present ourselves to the world and others

Presence: Is it just pretending?

Our sense of presence in the real world helps regulate our behaviour within it by telling us about the status and effectiveness of our actions. As such, this ability offers us practical advantages in dealing effectively with the world. It is also an automatic or intuitive response to where and how we find ourselves in that it does not require conscious thought or deliberation. In contrast, the experience of presence or immersion in a movie, game or virtual environment is not automatic but is the product of our deliberate engagement with it, an engagement which first requires a disengagement or decoupling with the real world. Of course, we regularly decouple from the real world and embrace other, possible worlds every time we daydream, or engage in creative problem solving or, most importantly, for the purposes of this discussion, when we make-believe. We propose that make-believe is a plausible psychological mechanism which underpins the experience of mediated presence

Randomisation before consent : avoiding delay to time-critical intervention and ensuring informed consent

Peer reviewedPostprin