Search results for "Method"
showing 10 items of 13253 documents
Terrain data compression using wavelet-tiled pyramids for online 3D terrain visualization
2013
Last years have witnessed the widespread use of online terrain visualization applications. However, the significant improvements achieved in sensing technologies have allowed an increasing size of the terrain databases. These increasing sizes represent a serious drawback when terrain data must be transmitted and rendered at interactive rates. In this paper, we propose a novel wavelet-tiled pyramid for compressing terrain data that replaces the traditional multiresolution pyramid usually used in wavelet compression schemes. The new wavelet-tiled pyramid modifies the wavelet analysis and synthesis processes, allowing an efficient transmission and reconstruction of terrain data in those applic…
School PE through Internet discussion forums
2013
Background: Physical education is a subject that generates strong feelings and emotions, as can be seen in written accounts of PE experiences. It is also important to listen to students' voices in the research context. Nowadays, students can be listened to in a new way – through the Internet. Various discussion forums on the Internet make it possible for people to express themselves through real or imagined messages. It might be easier to express highly sensitive and even intimate thoughts on the Internet. Thus, the Internet might be an interesting open forum for teachers to think about new ways of developing teaching practices that would reduce negative experiences of PE.Purpose: The purpo…
Applying logistic regression to relevance feedback in image retrieval systems
2007
This paper deals with the problem of image retrieval from large image databases. A particularly interesting problem is the retrieval of all images which are similar to one in the user's mind, taking into account his/her feedback which is expressed as positive or negative preferences for the images that the system progressively shows during the search. Here we present a novel algorithm for the incorporation of user preferences in an image retrieval system based exclusively on the visual content of the image, which is stored as a vector of low-level features. The algorithm considers the probability of an image belonging to the set of those sought by the user, and models the logit of this prob…
Instruction of Digital Reading Strategies Based on Eye-Movements Modeling Examples
2018
During the last decade, several studies have proposed and tested different instructional methods for teaching digital reading strategies to young students. In this study, we have tested the effectiveness of a program combining eye-movements modeling examples (EMMEs) and contrasting cases to instruct ninth-grade students how to plan, evaluate, and monitor their digital reading. EMMEs are videos that display a dot representing the eye movements of a model and an oral transcription of her thoughts while answering a specific question in a hypertext. Students in the EMME condition obtain higher comprehension scores in a posttest performed 1 week after the instruction, as compared with a control…
Latent Semantic Description of Iconic Scenes
2005
It is proposed an approach for the automatic description of scenes using a LSA–like technique. The described scenes are composed by a set of elements that can be geometric forms or iconic representation of objects. Every icon is characterized by a set of attributes like shape, colour and position. Each scene is related to a set of sentences describing their content. The proposed approach builds a data driven vector semantic space where the scenes and the sentences are mapped. A new scene can be mapped in this created space accordingly to a suitable metric. Preliminary experimental results show the effectiveness of the procedure.
Spatio-Temporal Saliency Detection in Dynamic Scenes using Local Binary Patterns
2014
International audience; Visual saliency detection is an important step in many computer vision applications, since it reduces further processing steps to regions of interest. Saliency detection in still images is a well-studied topic. However, videos scenes contain more information than static images, and this additional temporal information is an important aspect of human perception. Therefore, it is necessary to include motion information in order to obtain spatio-temporal saliency map for a dynamic scene. In this paper, we introduce a new spatio-temporal saliency detection method for dynamic scenes based on dynamic textures computed with local binary patterns. In particular, we extract l…
A successful way for performing nutritional nursing assessment in older patients
2008
Aim. The aim of this study was to obtain increased knowledge and understanding about what can be promoting and facilitating for nurses to perform nutritional nursing assessment in older patients. Background. The frequency of older patients at nutritional risk or suffering from undernutrition is high in hospitals. Studies have shown frequent lack of awareness about signs of undernutrition as all patients are, for example, not weighed. Nurses’ descriptions about nutritional problems have also been found to be often vague and unspecific. Design. A qualitative design was used. Methods. Ten conveniently chosen registered nurses, working with older patients in two hospitals in western Sweden …
A family of kernel anomaly change detectors
2014
This paper introduces the nonlinear extension of the anomaly change detection algorithms in [1] based on the theory of reproducing kernels. The presented methods generalize their linear counterparts, under both the Gaussian and elliptically-contoured assumptions, and produce both improved detection accuracies and reduced false alarm rates. We study the Gaussianity of the data in Hilbert spaces with kernel dependence estimates, provide low-rank kernel versions to cope with the high computational cost of the methods, and give prescriptions about the selection of the kernel functions and their parameters. We illustrate the performance of the introduced kernel methods in both pervasive and anom…
Perceptually weighted optical flow for motion-based segmentation in MPEG-4 paradigm
2000
In the MPEG-4 paradigm, the sequence must be described in terms of meaningful objects. This meaningful, high-level representation should emerge from low-level primitives such as optical flow and prediction error which are the basic elements of previous-generation video coders. The accuracy of the high-level models strongly depends on the robustness of the primitives used. It is shown how perceptual weighting in optical flow computation gives rise to better motion estimates which consistently improve motion-based segmentation compared to equivalent unweighted motion estimates.
Investigation of buckling characteristics of cracked variable stiffness composite plates by an eXtended Ritz approach
2021
Abstract Variable Angle Tow (VAT) composite plates are characterized by in-plane variable stiffness properties, which opens to new concepts of stiffness tailoring and optimization to achieve higher structural performance for advanced lightweight structures where damage tolerance consideration are often mandatory. In this paper, a single-domain eXtended Ritz formulation is proposed to study the buckling behaviour of variable stiffness laminated cracked plates. The plate behaviour is described by the first order shear deformation theory whose generalized displacements, namely reference plane translations and rotations, are expressed via suitable admissible trial functions. These consist of a …