Search results for "pattern"
showing 10 items of 4203 documents
Identifying objectives for a learning space management system with value-focused thinking
2017
A classroom with a blackboard and some rows of desks is obsolete in special education. Depending on the needs, some students may need more tactile and inspiring surroundings with various pedagogical accessories while others benefit from a simplified environment without unnecessary stimuli. This understanding is applied to a new Finnish special education school building with open and adaptable learning spaces. We have joined the initiative creation process by developing software support for these new spaces in the form of a learning space management system. Participatory design and value-focused thinking were implemented to elicit the actual values of all the stakeholders involved and transf…
Consensus guidelines for the detection of immunogenic cell death
2014
Apoptotic cells have long been considered as intrinsically tolerogenic or unable to elicit immune responses specific for dead cell-associated antigens. However, multiple stimuli can trigger a functionally peculiar type of apoptotic demise that does not go unnoticed by the adaptive arm of the immune system, which we named "immunogenic cell death" (ICD). ICD is preceded or accompanied by the emission of a series of immunostimulatory damage-associated molecular patterns (DAMPs) in a precise spatiotemporal configuration. Several anticancer agents that have been successfully employed in the clinic for decades, including various chemotherapeutics and radiotherapy, can elicit ICD. Moreover, defect…
The time course of processing handwritten words: An ERP investigation
2021
Available online 25 June 2021. Behavioral studies have shown that the legibility of handwritten script hinders visual word recognition. Furthermore, when compared with printed words, lexical effects (e.g., word-frequency effect) are magnified for less intelligible (difficult) handwriting (Barnhart and Goldinger, 2010; Perea et al., 2016). This boost has been interpreted in terms of greater influence of top-down mechanisms during visual word recognition. In the present experiment, we registered the participants’ ERPs to uncover top-down processing effects on early perceptual encoding. Participants’ behavioral and EEG responses were recorded to high- and low-frequency words that varied in scr…
A Specialized Architecture for Color Image Edge Detection Based on Clifford Algebra
2013
Edge detection of color images is usually performed by applying the traditional techniques for gray-scale images to the three color channels separately. However, human visual perception does not differentiate colors and processes the image as a whole. Recently, new methods have been proposed that treat RGB color triples as vectors and color images as vector fields. In these approaches, edge detection is obtained extending the classical pattern matching and convolution techniques to vector fields. This paper proposes a hardware implementation of an edge detection method for color images that exploits the definition of geometric product of vectors given in the Clifford algebra framework to ex…
Fast, Reliable Head Tracking Under Varying Illumination
2003
An improved technique for 3D head tracking under varying illumination conditions is proposed. The head is modeled as a texture mapped cylinder. Tracking is formulated as an image registration problem in the cylinder's texture map image. To solve the registration problem in the presence of lighting variation and head motion, the residual error of registration is modeled as a linear combination of texture warping templates and orthogonal illumination templates. Fast and stable on-line tracking is then achieved via regularized weighted least squares minimization of the registration error. The regularization term tends to limit potential ambiguities that arise in the warping and illumination te…
Spatio-temporal cluster detection of chickenpox in Valencia, Spain in the period 2008-2012.
2015
Chickenpox is a highly contagious airborne disease caused by <em>Varicella zoster</em>, which affects nearly all non-immune children worldwide with an annual incidence estimated at 80-90 million cases. To analyze the spatiotemporal pattern of the chickenpox incidence in the city of Valencia, Spain two complementary statistical approaches were used. First, we evaluated the existence of clusters and spatio-temporal interaction; secondly, we used this information to find the locations of the spatio-temporal clusters via the space-time permutation model. The first method used detects any aggregation in our data but does not provide the spatial and temporal information. The second me…
Factor analysis-based approach for early uptake automatic quantification of breast cancer by 18F-FDG PET images sequence
2014
International audience; Factor Analysis of Medical Image Sequences (FAMIS) is recognized as one pioneer successfully used approach for analyzing especially dynamic images' sequence for estimating kinetics and associated compartments having a physiological meaning. Some studies tried to extend the exploring of this approach to analyze Positron Emission Tomography (PET) image modality for dynamic sequences. PET images with 18F-fluorodesoxyglucose (18F-FDG) is the gold standard for in vivo, evaluation of tumor glucose metabolism and is widely used in clinical oncology. In this paper, a novel approach is proposed to obtain an automated quantification method for early accumulation of 18F-FDG tra…
Organization of intensive cardiac care units in Europe: Results of a multinational survey
2020
Background: The present survey aims to describe the intensive cardiac care unit organization and admission policies in Europe. Methods: A total of 228 hospitals (61% academic) from 27 countries participated in this survey. In addition to the organizational aspects of the intensive cardiac care units, including classification of the intensive cardiac care unit levels, data on the admission diagnoses were gathered from consecutive patients who were admitted during a two-day period. Admission policies were evaluated by comparing illness severity with the intensive cardiac care unit level. Gross national income was used to differentiate high-income countries (n=13) from middle-income countries…
Comparison of region of interest segmentation methods for video-based heart rate measurements
2018
International audience; Conventional contact photoplethysmography (PPG) sensors are not suitable in situations of skin damage or when unconstrained movement is required. As a consequence, remote photoplethysmography (rPPG) has recently emerged because it provides remote physiological measurements without expensive hardware and improves comfort for long-term monitoring. RPPG estimation methods use the spatially averaged RGB values of pixels in a Region Of Interest (ROI) to generate a temporal RGB signal. The selection of ROI is a critical first step to obtain reliable pulse signals and must contain as many skin pixels as possible with a low percentage of non-skin pixels. In this paper, we ex…
Remote Photoplethysmography measurement using constrained ICA
2017
Remote Photoplethysmography (rPPG) is a technique that consists in estimating physiological parameters such as heart rate from live or recorded video sequences taken by conventional camera or even webcams. This technique is increasingly used in many application fields thanks to its simplicity and affordability. The basic idea is that the arterial blood flow shows regularity due to the heartbeat. This regularity is manifested by very small periodic variations in the color of the skin, which can be isolated and quantified by signal and image processing methods. In this context, Independent Component Analysis (ICA) is largely used to separate the signal due to arterial flow from signals from o…