Search results for " description"
showing 10 items of 192 documents
Discovering single classes in remote sensing images with active learning
2012
When dealing with supervised target detection, the acquisition of labeled samples is one of the most critical phases: the samples must be yet representative of the class of interest, but must also be found among a vast majority of non-target examples. Moreover, the efficiency of the search is also an issue, since the samples labeled as background are not used by target detectors such as the support vector data description (SVDD). In this work we propose a competitive and effective approach to identify the most relevant training samples for one-class classification based on the use of an active learning strategy. The SVDD classifier is first trained with insufficient target examples. It is t…
FPGA Implementation of an Adaptive Filter Robust to Impulsive Noise: Two Approaches
2011
Adaptive filters are used in a wide range of applications such as echo cancellation, noise cancellation, system identification, and prediction. Its hardware implementation becomes essential in many cases where real-time execution is needed. However, impulsive noise affects the proper operation of the filter and the adaptation process. This noise is one of the most damaging types of signal distortion, not always considered when implementing algorithms, particularly in specific hardware platforms. Field-programmable gate arrays (FPGAs) are used widely for real-time applications where timing requirements are strict. Nowadays, two main design processes can be followed for embedded system design…
Validation of a Short Form of Job Crafting Scale in a Spanish Sample
2018
AbstractApplications of job crafting are widespread in the professional practice. In an attempt to measure this phenomenon, Tims, Bakker and Derks (2012) developed a Job Crafting Scale based on the Job Demand-Resources model (JD-R) and validated it in a Dutch sample. However, its application to other cultural contexts presented some difficulties. The present work aimed to validate a shorter version of scale by Tims et al. (2012) in a Spanish sample (n = 1,647). The data were randomly split in two independent subsamples (Sample 1: Explorative; Sample 2: Confirmative). The exploratory factor analysis showed a three-factor structure. Through a confirmatory factor analysis, the four-dimensional…
Double Retrotransverse Foramen of Atlas (C1)
2018
Background The retrotransverse foramen is a nonmetric variant of C1 that consists of an abnormal accessory foramen on the posterior root of the transverse process. Case Description During a study on the prevalence of the retrotransverse foramen in 150 dry C1 vertebrae, we observed an exceptional C1 (0.67%) with a right double retrotransverse foramen of the 14 C1 vertebrae (9.3%). This has not been reported previously in the literature. No osteogenic reaction and no degenerative signs were observed in this C1 with the double retrotransverse foramen. Conclusions Neurosurgeons should be aware of the possible presence of the “conventional” retrotransverse foramen and the “exceptional” double re…
Reproducibility of optical biometry using partial coherence interferometry: intraobserver and interobserver reliability
2001
Abstract Purpose: To evaluate the intraobserver and interobserver variability in axial length (AL), anterior chamber depth (ACD), and corneal radius measurements using an optical biometry instrument based on partial coherence interferometry (PCI). Setting: Johannes Gutenberg University, Mainz, Germany. Methods: In this observational case series and interobserver reliability trial, 30 healthy, emmetropic to moderately myopic eyes of 15 volunteers were evaluated. The AL, ACD, and corneal radius were measured 20 times in 10 eyes by 1 observer to evaluate the intraobserver variability. To evaluate the interobserver variability, the measurements were taken in 20 eyes by 5 different observers. Me…
Factors associated with the activities of safety representatives in Spanish workplaces
2007
Objective: To describe the activities of safety representatives in workplaces in Spain. Methods: A specific questionnaire was applied to a representative sample of safety representatives. Activities developed during the past year, presented in a closed ended list, were categorised into three groups: information and advising; participation in occupational health management; and pressure on or negotiation with employers. Personal phone interviews were conducted from September to December 2004. A sample of 1201 interviews was attained. Crude and multivariate analyses were carried out. Results: Spanish safety representatives were mostly men (76%), aged 26 to 45 years (62%), with fixed contracts…
The Retrotransverse Foramen of the Atlas Is not a Modern Anatomic Variation
2019
Background The retrotransverse foramen (RTF) is a nonmetric variant of the atlas vertebra that consists of an abnormal accessory foramen located on the posterior root of the transverse process and it extends from the posterior root of the transverse process to the root of the posterior arch. Its presence has been related to regional variations of the venous circulation. It is currently unknown whether the RTF is a modern or an ancient anatomic variation. Case Description We analyzed the skeletal remains from the late-ancient Roman necropolis (II-VI centuries ad ) of La Boatella (Valencia, Spain) and we found a well-preserved individual skeleton that presented with a left retrotransverse for…
Quantifying stenosis in renal arteriograms: a fuzzy syntactic analysis.
1999
AbstractThe introduction of fuzzy logic improves a system for the automatic quantification of renal artery lesions seen in digital subtraction angiograms. A two-step approach has been followed. An earlier system based on non-fuzzy syntactic analysis provided a clear symbolic description of the stenotic lesions. Although this system worked correctly, it did not take into account the variability and uncertainty inherent to image processing and to knowledge on the reference diameter. This system has been improved by the introduction of fuzzy logic in the representation of the reference diameter. It provides a description of the stenosis in terms of fuzzy quantities. To illustrate the benefits …
ABM of Civil Violence: ODD Description
2017
This chapter contains a description of the proposed agent-based model, using the well-known “Overview, Design Concepts and Details” protocol. The model was implemented in NetLogo and is based on the same two types of agents—citizens and law-enforcement—as in Epstein’s model, but “citizen” agents have one subtype (“activist”) used for implementing network influence effects. The salient aspects of the model description are centered on the submodels for the risk perception, the expression of hardship in terms of value-sensitive relative deprivation, endogenous legitimacy feedback and network influence effects, which provide extensions to Epstein’s model. The model includes two networks called …
FORMAL CONCEPTION OF ROUGH SETS
1996
In the paper we present a formal description of rough sets within the framework of the generalized set theory, which is interpreted in the set approximation theory. The rough sets are interpreted as approximations, which are defined by means of the Pawlak's rough sets.