Search results for "Human-computer Interaction"
showing 10 items of 605 documents
Informal learning through expertise mining in the social web
2012
The advent of Web 2.0, also called the Social Web, has changed the way people interact with the Web. Assisted by the technologies associated with this new trend, users now play a much more active role as content providers. This Web paradigm shift has also changed how companies operate and interact with their employees, partners and customers. The challenge for companies and research institutions is now to develop semi-automated tools for gathering usable and explicit knowledge from such content. With the aim of facilitating the achievement of such a challenge, in this work a platform architecture for informal learning, which is based on semantic technologies, is proposed. Such platform perm…
Towards EEG-Based Haptic Interaction within Virtual Environments
2019
International audience; Current virtual environments (VE) enable perceiving haptic stimuli to facilitate 3D user interaction, but lack brain-interfacial contents. Using electroencephalography (EEG), we undertook a feasibility study on exploring event-related potential (ERP) patterns of the user's brain responses during haptic interaction within a VE. The interaction was flying a virtual drone along a curved transmission line to detect defects under the stimuli (e.g., force increase and/or vibrotactile cues). We found that there were variations in the peak amplitudes and latencies (as ERP patterns) of the responses at about 200 ms post the onset of the stimuli. The largest negative peak occu…
Use of a Virtual Environment to Engage Motor and Postural Abilities in Elderly Subjects With and Without Mild Cognitive Impairment (MAAMI Project)
2016
Objectives: In the context of rehabilitation, the use of new technology such as Virtual Reality Technology (VRT) offers multiple possibilities to modulate the functional stimulation of subjects according to needs. Material and methods: In this study, the validity and reliability of our VRT system were investigated in fifteen healthy aged adults (HAA) and seven aged subjects with mild cognitive impairment (MCI). One implicit session was designed through two virtual environments (VEs) in order to induce the adapted activities associated with balance and postural control. In comparison, the same activities were achieved in explicit sessions with a physiotherapist. This cross-over study made us…
Visual acuity and contrast sensitivity screening with a new iPad application
2016
We present a new iPad application (app) for a fast assessment of Visual Acuity (VA) and Contrast Sensitivity (CS) whose reliability and agreement was evaluated versus a commercial screening device (Optec 6500). The measurement of VA was programmed in the app in accordance with the Amblyopia Treatment Study protocol. The CS was measured with sinusoidal gratings of four different spatial frequencies: 3, 6, 12 and 18 cpd at the same contrast values of the Functional Acuity Contrast Test (FACT) included in the Optec 6500. Forty-five healthy subjects with monocular corrected visual acuities better than 0.2 logMAR participated in the agreement study. Bland-Altman analyses were performed to assess…
Twitch interpolation during equal-intensity voluntary and electrically-evoked isometric contractions of the quadriceps muscle
2005
It has been suggested that, during contractions triggered by electrical stimulation, motor units are recruited in a reversed sequence compared to voluntary contraction. The classic view is that lar...
Stereoscopic Viewing Enhances Visually Induced Motion Sickness but Sound Does Not
2012
Optic flow in visual displays or virtual environments often induces motion sickness (MS). We conducted two studies to analyze the effects of stereopsis, background sound, and realism (video vs. simulation) on the severity of MS and related feelings of immersion and vection. In Experiment 1, 79 participants watched either a 15-min-long video clip taken during a real roller coaster ride, or a precise simulation of the same ride. Additionally, half of the participants watched the movie in 2D, and the other half in 3D. MS was measured using the Simulator Sickness Questionnaire (SSQ) and the Fast Motion Sickness Scale (FMS). Results showed a significant interaction for both variables, indicatin…
Video-assisted surgery: suggestions for failure prevention in laparoscopic cholecystectomy
2014
Background: Surgery differs from other medical specialties in its execution. It is often complex and includes considerable individual variations. Observing problems in operating theatres (OT) allows for the identification of system failures which should be defined for learning purposes to increase patient safety and enhance general safety culture within hospital organizations. This study evaluates a common video-assisted surgical procedure, laparoscopic cholecystectomy (LC) through failure analysis. The profile of the LC procedure and failure sources is presented. Methods: Data consisted video-observations and interviews concerning twelve LC operations performed at a day surgery unit. All o…
Biomechanical evaluation of a new treatment method for distal tibia fractures
2015
Distal tibial fractures are often the result of high-energy impacts combined with excessive soft tissue injury. Treatment options include either open reduction and internal fixation usually as a mi...
Early cortical processing of vection-inducing visual stimulation as measured by event-related brain potentials (ERP)
2019
Abstract Visual motion stimuli can induce the perception of self-motion in stationary observers (known as vection). In the present study, we investigated the sensory processing underlying vection by measuring the human event-related brain potentials (ERPs) elicited by the movement onset of a visual stimulus. We presented participants a visual stimulus consisting of alternating black-and-white vertical bars that moved in horizontal direction, creating the sensation of vection. The stimulus was presented on a screen that was divided into a central and a surrounding peripheral visual area. Both areas moved independently from each other, resulting in four different movement patterns: the periph…
Predictors of visually induced motion sickness in women
2019
Abstract Background Visually induced motion sickness (VIMS) is commonly experienced when visual motion information is in conflict with motion information provided by the vestibular system and/or tactile and kinesthetic senses. According to some studies, women experience higher levels of VIMS than men, whereas other studies do not find this to be the case. Hypothesis This study investigated whether gender differences can be attributed to changes in VIMS-susceptibility due to the menstrual cycle and perceived menstrual pain. We hypothesized that higher perceived menstrual pain correlates positively with VIMS susceptibility. Methods We measured the influence of estimated concentrations of four…