Search results for "Human-Computer Interaction"
showing 10 items of 605 documents
Appetizer or main dish? Explaining the use of Facebook news posts as a substitute for other news sources
2019
An increasing number of, especially younger, users use Facebook as their primary source for news about political and societal issues. At the same time, research suggests that Facebook use contributes to societal knowledge gaps. Against this background, we investigate the antecedents of using Facebook as a substitute for other news sources. We argue that exposure to news posts on Facebook increases the feeling of being well-informed, regardless of actual knowledge acquisition. This might lead users, especially those with a low need for cognition (NfC), to use Facebook as a substitute for other news sources. We test these assumptions with an online survey (n=390) of German Internet users. Res…
An fMRI Study to Analyze Neural Correlates of Presence during Virtual Reality Experiences
2013
[EN] In the field of virtual reality (VR), many efforts have been made to analyze presence, the sense of being in the virtual world. However, it is only recently that functional magnetic resonance imaging (fMRI) has been used to study presence during an automatic navigation through a virtual environment. In the present work, our aim was to use fMRI to study the sense of presence during a VR-free navigation task, in comparison with visualization of photographs and videos (automatic navigations through the same environment). The main goal was to analyze the usefulness of fMRI for this purpose, evaluating whether, in this context, the interaction between the subject and the environment is perf…
Solubility and diffusion of nitrogen in maltodextrin/protein tablets.
2002
The gas transport properties of compacted tablets consisting of an amorphous mixture of maltodextrin and sodium caseinate were studied by dissolving nitrogen gas in the tablets and then determining the gas release over time as a function of temperature and water activity. Gas was dissolved in the tablet matrix by heating the tablets under pressure, generally to temperatures above the glass transition temperature of the matrix, holding them at these conditions for a specified time and then rapidly cooling them while maintaining the external pressure. The solubility of nitrogen was found to be largely determined by the free volume of the matrix, which in turn can be influenced to some degree …
Solution of time-independent Schrödinger equation by the imaginary time propagation method
2007
Numerical solution of eigenvalues and eigenvectors of large matrices originating from discretization of linear and non-linear Schrodinger equations using the imaginary time propagation (ITP) method is described. Convergence properties and accuracy of 2nd and 4th order operator-splitting methods for the ITP method are studied using numerical examples. The natural convergence of the method is further accelerated with a new dynamic time step adjustment method. The results show that the ITP method has better scaling with respect to matrix size as compared to the implicitly restarted Lanczos method. An efficient parallel implementation of the ITP method for shared memory computers is also demons…
Multimode OPOs as Sources for Multipartite Entanglement
2009
We present here multimode OPOs as a source of multimode squeezing and multipartite entanglement of continuous-wave light beams, with applications to the engineering of multimode states of light in the spatial and spectral domains.
“It Is Not the Robot Who Learns, It Is Me.” Treating Severe Dysgraphia Using Child–Robot Interaction
2021
Writing disorders are frequent and impairing. However, social robots may help to improve children's motivation and to propose enjoyable and tailored activities. Here, we have used the Co-writer scenario in which a child is asked to teach a robot how to write via demonstration on a tablet, combined with a series of games we developed to train specifically pressure, tilt, speed, and letter liaison controls. This setup was proposed to a 10-year-old boy with a complex neurodevelopmental disorder combining phonological disorder, attention deficit/hyperactivity disorder, dyslexia, and developmental coordination disorder with severe dysgraphia. Writing impairments were severe and limited his parti…
Using protection motivation theory in the design of nudges to improve online security behavior
2019
Abstract We conducted an online experiment (n = 2024) on a representative sample of internet users in Germany, Sweden, Poland, Spain and the UK to explore the effect of notifications on security behaviour. Inspired by protection motivation theory (PMT), a coping message advised participants on how to minimize their exposure to risk and a threat appeal highlighted the potential negative consequences of not doing so. Both increased secure behavior – but the coping message significantly more so. The coping message was also as effective as both messages combined, but not so the threat appeal. Risk attitudes, age and country had a significant effect on behavior. Initiatives seeking to promote se…
Pulsed X‐Ray Radiation Responses of Solarization‐Resistant Optical Fibers
2018
International audience; The transient radiation‐induced attenuation (RIA) of two different versions of pure‐silica‐core (PSC) multimode optical fibers (so‐called “solarization‐resistant” fibers) exposed to nanosecond 1 MeV X‐ray pulses are investigated. On‐line RIA spectra measurements at both room temperature (RT) and liquid nitrogen temperatures (LNT) in the range 1–3.5 eV are performed. Following the RIA kinetics, the properties of the metastable defects that are bleached just after the pulse are discussed. The spectral decomposition of the RIA is performed using known Gaussian bands associated to point defects absorbing in this spectral range. For both fiber types, the generation and th…
Spatiotemporal pulse shaping with multimode nonlinear guided waves
2018
We experimentally and theoretically investigate complex temporal pulse reshaping that accompanies Kerr beam self-cleaning in multimode optical fibers. We also study the output beam shape dependence on initial conditions.
Static output-feedback controller design for vehicle suspensions: an effective two-step computational approach
2014
In this study, a novel two-step methodology is applied in designing static output-feedback controllers for a class of vehicle suspension systems. Following this approach, an effective synthesis of static output-feedback controllers can be carried out by solving two consecutive linear matrix inequality optimisation problems. To illustrate the main features of the proposed design strategy, two different static output-feedback H 8 controllers are designed for a quarter-car suspension system. The first of those controllers uses the suspension deflection and the sprung mass velocity as feedback information, whereas the second one only requires the sprung mass velocity to compute the control acti…