Search results for "pattern"
showing 10 items of 4203 documents
Deformable object segmentation in ultra-sound images
2013
Breast cancer is the second most common type of cancer being the leading cause of cancer death among females both in western and in economically developing countries. Medical imaging is key for early detection, diagnosis and treatment follow-up. Despite Digital Mammography (DM) remains the reference imaging modality, Ultra-Sound (US) imaging has proven to be a successful adjunct image modality for breast cancer screening, specially as a consequence of the discriminative capabilities that US offers for differentiating between solid lesions that are benign or malignant. Despite US usability,US suffers inconveniences due to its natural noise that compromises the diagnosis capabilities of radio…
Comparative training procedures to learn odor descriptors: effects on profiling performance
1999
Three groups of ten naive assessors were recruited to perform an odor profiling of 10 orange juices using 8 odor descriptors, These panels differed on the way they learned each descriptor. Group 1R learned to match one descriptor with one external standard; group 3R learned to associate one descriptor with 3 external standards; group 0R defined by itself the 8 descriptors from a set of orange juices. Results showed that the use of one standard per descriptor seemed to be only efficient when the standard was typical of the odor perception in the orange juices. Learning one odor concept with 3 standards led to redundant use of discriminant descriptors and failed on the agreement among assesso…
Comparing Boosting and Bagging for Decision Trees of Rankings
2021
AbstractDecision tree learning is among the most popular and most traditional families of machine learning algorithms. While these techniques excel in being quite intuitive and interpretable, they also suffer from instability: small perturbations in the training data may result in big changes in the predictions. The so-called ensemble methods combine the output of multiple trees, which makes the decision more reliable and stable. They have been primarily applied to numeric prediction problems and to classification tasks. In the last years, some attempts to extend the ensemble methods to ordinal data can be found in the literature, but no concrete methodology has been provided for preference…
Can ‘Fellow of the European Board of Ophthalmology Subspecialty Diploma in Glaucoma,’ a subspecialty examination on glaucoma induce the qualification…
2016
From 2015, the examination of Fellow of the European Board of Ophthalmology Subspecialty Diploma in Glaucoma (FEBOS-Glaucoma) was launched by the European Board of Ophthalmology (EBO) in cooperation with the European Glaucoma Society (EGS). This opinion aims at disclosing the background of the examination, prerequisite to the examination, and the value of the FEBOS-Glaucoma diploma.
Epidemiological survey on third molar agenesis and facial pattern among adolescents requiring orthodontic treatment
2017
Background The aim of this study was to determine the association between facial pattern according to Ricketts cephalometric analysis, and prevalence of third molar agenesis, taking subject age and gender as control variables. Material and methods An epidemiological survey was conducted based on a sample of 224 candidates for orthodontic treatment aged 12 to 24 (n=224). Third molar agenesis was recorded using Ricketts cephalometric analyses of lateral teleradiographs and panoramic radiographs. The risk for agenesis was predicted considering the 5 Vert Index parameters (facial axis, facial depth, mandibular plane angle, lower facial height and mandibular arch), facial type (brachyfacial, mes…
Comparison of pharyngeal airway volume in different skeletal facial patterns using cone beam computed tomography
2018
Background This study aimed to compare the pharyngeal airway volume in class I,II and III skeletal malocclusion patients using cone beam computed tomography (CBCT). Material and Methods This retrospective, cross sectional study was conducted on lateral cephalograms of 71 patients derived from their CBCT scans. Using the ANB angle, the patients were divided into class I,II and III malocclusion. Two observers used Dolphin 3D software to calculate the pharyngeal airway volume, airway area, minimum axial area, minimum area location, airway length and morphology. Data were analyzed using one-way ANOVA, Kruskal-Wallis test, Tukey's test, Spearman's correlation coefficient and multiple regression …
Recent Advances in Static Output-Feedback Controller Design with Applications to Vibration Control of Large Structures
2014
Published version of an article in the journal: Modeling, Identification and Control. Also available from the publisher at: http://dx.doi.org/10.4173/mic.2014.3.4 Open Access In this paper, we present a novel two-step strategy for static output-feedback controller design. In the first step, an optimal state-feedback controller is obtained by means of a linear matrix inequality (LMI) formulation. In the second step, a transformation of the LMI variables is used to derive a suitable LMI formulation for the static output-feedback controller. This design strategy can be applied to a wide range of practical problems, including vibration control of large structures, control of oshore wind turbine…
Static output-feedback controller design for vehicle suspensions: an effective two-step computational approach
2014
In this study, a novel two-step methodology is applied in designing static output-feedback controllers for a class of vehicle suspension systems. Following this approach, an effective synthesis of static output-feedback controllers can be carried out by solving two consecutive linear matrix inequality optimisation problems. To illustrate the main features of the proposed design strategy, two different static output-feedback H 8 controllers are designed for a quarter-car suspension system. The first of those controllers uses the suspension deflection and the sprung mass velocity as feedback information, whereas the second one only requires the sprung mass velocity to compute the control acti…
A Note about Eigenvalues, SVD and PCA
2013
Notes on eigen-decomposition, PCA, SVD and connexions.
Fiber Bragg gratings with various chirp profiles made in etched tapers
1996
We have studied, both theoretically and experimentally, fibre Bragg gratings with a number of different chirp profiles. These chirp profiles can be easily achieved with a recently demonstrated technique involving a taper of desired profile being etched into the cladding of a fibre. Performances of gratings with linear, quadratic, periodically modulated and step chirp profiles are numerically analysed. The versatility of the technique is demonstrated when linearly and quadratically chirped gratings were made as examples of continuous chirp and gratings with step chirps were made as examples of discontinuously chirped structure.