Search results for "Interaction"
showing 10 items of 5710 documents
Iron-clay interactions: Detailed study of the mineralogical transformation of claystone with emphasis on the formation of iron-rich T-O phyllosilicat…
2014
International audience; Iron-minerals-water interactions are of primary importance in the contexts of underground structure engineering (e.g. reactive barriers or deep geological storage) and for the understanding of secondary alteration processes in primitive meteorites. To improve our understanding of these systems, we determine the mineralogical transformations induced by the association of iron and silicates during a cooling through an experimental simulation of iron-clay interactions with a step-by-step procedure in the range of 90 degrees C to 40 degrees C. The run products and solutions are well characterised, by means of different techniques (X-ray diffraction, scanning and transmis…
Scavenging of sulphur, halogens and trace metals by volcanic ash: The 2010 Eyjafjallajökull eruption
2013
The Eyjafjallajökull volcanic eruption in 2010 released considerable amounts of ash into the high troposphere-low stratosphere, leading to unprecedented disruption of air traffic over Europe. The role of such fine-grained tephra in adsorbing, and therefore rapidly scavenging, volcanogenic volatile elements such as sulphur and halogens, is explored here. We report on results (major to trace element chemistry) of leaching experiments carried out on 20 volcanic ash samples, taken from the deposits of the main phases of the eruption (March–April 2010), or directly while falling (5–9 May 2010). Ash leachate solutions from Eyjafjallajökull are dominated – among cations – by Ca and Na, and display…
DEFINITION ET ETUDE DES PERFORMANCES D'UN DETECTEUR DE STRUCTURES CURVILINEAIRES. APPLICATION A LA STEREOSCOPIE ET LA DETECTION D'OBJETS FILAIRES
2008
The work presented in this paper falls under the domain of matching. In this context, we try to show the interest of using the curvilinear regions in order to enhance the global performance of various matching applications. A brand new detector for curvilinear regions is introduced (CRD), along with the specific curvilinear regions descriptor (CRD) required. Performance evaluations were done in two parts: First, we evaluated and compared the segmentations performances of our detector, in particular on a retina vessels segmentation application. And second, we estimated the matching performances using K. Mykolajczyk toolkit. This methodology helps obtaining intrinsic performances and comparin…
Repeatability of Feather Mite Prevalence and Intensity in Passerine Birds
2014
Understanding why host species differ so much in symbiont loads and how this depends on ecological host and symbiont traits is a major issue in the ecology of symbiosis. A first step in this inquiry is to know whether observed differences among host species are species-specific traits or more related with host-symbiont environmental conditions. Here we analysed the repeatability (R) of the intensity and the prevalence of feather mites to partition within- and among-host species variance components. We compiled the largest dataset so far available: 119 Paleartic passerine bird species, 75,944 individual birds, ca. 1.8 million mites, seven countries, 23 study years. Several analyses and appro…
Aging effects and feasibility of statistical learning tasks across modalities
2021
Knowledge on statistical learning (SL) in healthy elderly is scarce. Theoretically, it is not clear whether aging affects modality-specific and/or domain-general learning mechanisms. Practically, there is a lack of research on simplified SL tasks, which would ease the burden of testing in clinical populations. Against this background, we conducted two experiments across three modalities (auditory, visual and visuomotor) in a total of 93 younger and older adults. In Experiment 1, SL was induced in all modalities. Aging effects appeared in the tasks relying on an explicit posttest to assess SL. We hypothesize that declines in domain-general processes that predominantly modulate explicit learn…
Architecture to Serve Disabled and Elderly
2013
We propose an architecture (discussed in the context of a dressing and cleaning application for impaired and elderly persons) that combines a cognitive framework that generates motor commands with the MOSAIC architecture which selects the right motor command according to the proper context. The ambition is to have robots able to understand humans intentions (dressing or cleaning intentions), to learn new tasks only by observing humans, and to represent the world around it by using conceptual spaces. The cognitive framework implements the learning by demonstration paradigm and solves the related problem to map the observed movement into the robot motor system. Such framework is assumed to wo…
Children’s Interactions Within a Virtual Reality Environment for Learning Chemistry
2017
This paper presents a virtual reality based solution for learning. Multimodal interactions are proposed to support students’ engagement through active experimentation and reflective observation. Students tasks are provided within an immersive virtual outdoor environment created using a human-centred design approach. Junior high school teachers and students between ages 14 and 16 were involved in design and test activities. Observations, video recordings, and interviews were used in data collection. Three interaction modalities were provided and tested: visual, auditory and kinesthetic/tangible interactions. The students involved in user testing showed great interest to learn in such an envi…
Single-channel EEG-based subject identification using visual stimuli
2021
Electroencephalography (EEG) signals have been recently proposed as a biometrics modality due to some inherent advantages over traditional biometric approaches. In this work, we studied the performance of individual EEG channels for the task of subject identification in the context of EEG-based biometrics using a recently proposed benchmark dataset that contains EEG recordings acquired under various visual and non-visual stimuli using a low-cost consumer-grade EEG device. Results showed that specific EEG electrodes provide consistently higher identification accuracy regardless of the feature and stimuli types used, while features based on the Mel Frequency Cepstral Coefficients (MFCC) provi…
Neural Multimodal Belief Tracker with Adaptive Attention for Dialogue Systems
2019
Multimodal dialogue systems are attracting increasing attention with a more natural and informative way for human-computer interaction. As one of its core components, the belief tracker estimates the user's goal at each step of the dialogue and provides a direct way to validate the ability of dialogue understanding. However, existing studies on belief trackers are largely limited to textual modality, which cannot be easily extended to capture the rich semantics in multimodal systems such as those with product images. For example, in fashion domain, the visual appearance of clothes play a crucial role in understanding the user's intention. In this case, the existing belief trackers may fail …
Using Internet videos to learn about controversies: Evaluation and integration of multiple and multimodal documents by primary school students
2020
Abstract In many Internet videos authors appear in front of the camera to present their particular view on a topic. Given the high consumption rate of Internet videos by teenagers, we explored the pros and cons of using these videos to learn about complex topics, compared to learning from textual web pages. Specifically, we studied how 207 primary school students (grades 4–6) evaluated and integrated multiple and multimodal web pages (text or video) while learning about the pros and cons of bottled water. Results showed no major role of modality in students' source memory, as measured by citations in their responses to an integration question and their memory for sources. Nevertheless, moda…