Pickup usability dominates: a brief history of mobile text entry research and adoption

Text entry on mobile devices (e.g. phones and PDAs) has been a research challenge since devices shrank below laptop size: mobile devices are simply too small to have a traditional full-size keyboard. There has been a profusion of research into text entry techniques for smaller keyboards and touch screens: some of which have become mainstream, while others have not lived up to early expectations. As the mobile phone industry moves to mainstream touch screen interaction we will review the range of input techniques for mobiles, together with evaluations that have taken place to assess their validity: from theoretical modelling through to formal usability experiments. We also report initial results on iPhone text entry speed

Feedback Control of Traveling Wave Solutions of the Complex Ginzburg Landau Equation

Through a linear stability analysis, we investigate the effectiveness of a noninvasive feedback control scheme aimed at stabilizing traveling wave solutions of the one-dimensional complex Ginzburg Landau equation (CGLE) in the Benjamin-Feir unstable regime. The feedback control is a generalization of the time-delay method of Pyragas, which was proposed by Lu, Yu and Harrison in the setting of nonlinear optics. It involves both spatial shifts, by the wavelength of the targeted traveling wave, and a time delay that coincides with the temporal period of the traveling wave. We derive a single necessary and sufficient stability criterion which determines whether a traveling wave is stable to all perturbation wavenumbers. This criterion has the benefit that it determines an optimal value for the time-delay feedback parameter. For various coefficients in the CGLE we use this algebraic stability criterion to numerically determine stable regions in the (K,rho) parameter plane, where rho is the feedback parameter associated with the spatial translation and K is the wavenumber of the traveling wave. We find that the combination of the two feedbacks greatly enlarges the parameter regime where stabilization is possible, and that the stability regions take the form of stability tongues in the (K,rho)--plane. We discuss possible resonance mechanisms that could account for the spacing with K of the stability tongues.Comment: 33 pages, 12 figure

Embeddings of rearrangement invariant spaces that are not strictly singular

We give partial answers to the following conjecture: the natural embedding of a rearrangement invariant space E into L_1([0,1]) is strictly singular if and only if G does not embed into E continuously, where G is the closure of the simple functions in the Orlicz space L_Phi with Phi(x) = exp(x^2)-1.Comment: Also available at http://www.math.missouri.edu/~stephen/preprint

A study of how people with learning disabilities experience social media

Section A: This section provides a systematic review of literature regarding how people with learning disabilities experience social media. The 15 studies are discussed in terms of study characteristics, method and findings. Quality appraisal tools were used to critique the studies. The findings were grouped into three themes; feelings and attitudes towards social media, opportunities (sub-themes; independence and autonomy, developing and expressing identity, connection and belonging), challenges and support networks. Implications for clinical practice were discussed and included the need for clinicians to enquire about PWLD social media use as both a potential resource and contributing factor to distress. Recommendations for future research included the creation of a model of social media use, in order to further understand how people with learning disabilities experience social media. Section B: This section presents a grounded theory study of interviews with people with learning disabilities who use social media. The data consisted of interviews with 11 individuals. A preliminary theoretical model is described, which suggests that people with learning disabilities face many opportunities and challenges when navigating the online world and that doing so leads to a sense of being seen online. This visibility poses opportunities for feelings of connection and belonging alongside increased exposure to disability stigma. Participants demonstrated a range of skills and attitudes in facing this stigma. Clinical and research implications are addressed