Social problems associated with falls of elderly citizens are becoming increasingly important because of the continuous growth of aging population. Automatic fall detection systems represent a possible answer to some of these problems, as they are useful to obtain help in case of serious injuries and to reduce the long-lie problem. Nevertheless, widespread adoption of these systems is strongly ...

Previous research has shown a wide array of age-related declines in vision. The current study examined the effects of perceptual learning (PL), external noise, and task difficulty in fine orientation discrimination with older individuals (mean age 71.73, range 65-91). Thirty-two older subjects participated in seven 1.5-h sessions conducted on separate days over a three-week period. A two-altern...

Subjects misjudge distances considerably when forced to rely on extra-retinal information. Nevertheless, they can reproducibly set a target to the same distance as a reference, or to double or half that distance, even when they have to look back and forth between them because they are prevented from seeing one when looking at the other. Our explanation for this apparent discrepancy is that peop...

Consumers are often forced to wade through many on-line reviews in order to make an informed product choice. This paper introduces OPINE, an unsupervised informationextraction system which mines reviews in order to build a model of important product features, their evaluation by reviewers, and their relative quality across products. Compared to previous work, OPINE achieves 22% higher precision...

We used anti-correlated stimuli to compare the correspondence problem in stereo and motion. Subjects performed a two-interval forced-choice disparity/motion direction discrimination task for different displacements. For anti-correlated 1d band-pass noise, we found weak reversed depth and motion. With 2d anti-correlated stimuli, stereo performance was impaired, but the perception of reversed mot...

We report an experiment that presented visually impaired and sighted users with virtually rendered haptic two-line graphs of various orientations. Participants made a forced-choice decision on whether a stimulus was convergent, parallel, or divergent. The use of complex linear haptic graphs was investigated. Possible variations in performance patterns for overall two-line orientations of 0 (ver...

The detectability of a sinusoidal grating was measured in a standard two-interval forced-choice experiment against backgrounds of noise gratings of the same orientation as the signal. The noise gratings were either spatially high-pass or low-pass filtered and were either unchanged in each observation interval (static) or flickering at a rate that depended on their cutoff frequency (dynamic). Sp...

When exploring a virtual environment using a point interaction type force feedback interface, users are forced to adopt a method of ‘temporal encoding’ in order to classify textured surfaces, due to the lack of spatially distributed cues on the fingerpad. Dynamic modelling of haptic interfaces suggests that high spatial frequency information may be attenuated, such that discrimination of stimul...

Rotational control and swing suppression of a crane suspended load model with traveling disturbance are studied. A rotational free rigid body suspended by a single rope is controlled using three inertia rotors. The end-supporting-point of the single rope is forced to be traveled as disturbance. Control angles and angular velocities are derived from measured data of fiber optic gyros installed o...

Tests that allow the precise determination of psychophysical thresholds for vibration and grating orientation provide valuable information about mechanosensory function that are relevant for clinical diagnosis as well as for basic research. Here, we describe two psychophysical tests designed to determine the vibration detection threshold (automated system) and tactile spatial acuity (handheld d...