Search results for " function"
showing 10 items of 9395 documents
Some applications of a theorem of Shirshov to language theory
1983
Some applications of a theorem of Shirshov to language theory are given: characterization of regular languages, characterization of bounded languages, and a sufficient condition for a language to be Parikh-bounded.
<em>Saccharomyces boulardii</em>: probiotic yeast for craft beer production, growth analysis and biovolume estimation
2018
In recent years, an increase in the consumer interest has been observed for craft beers, which are unpasteurized and unfiltered. Thus, the use of probiotic starters remaining in the craft beers could significantly increase health benefits. Here, the first study on the use of the probiotic Sacharomyces boulardii (Sb) yeast as single starter for craft brewing at 20 L scale is presented. The probiotic biomass growth was studied in bioreactor batch culture and modelled by the logistic and Gompertz equations. Finally, the probiotic biovolume of Sb was estimated from microscopy images. All these experiments were compared with those obtained with a commercial Sacharomyces cerevisiae (Sc) yeast str…
Adaptation of a German Multidimensional Networking Scale into English
2011
Networking refers to building and maintaining personal contacts in order to obtain resources that, in turn, enhance one’s career success and work performance. This study reports the translation and adaptation of a multifaceted German networking scale ( Wolff & Moser, 2006 ) into English and focuses on the equivalence of the two language versions. Going beyond the often used translation-backtranslation method, we used a parallel translation-backtranslation method in combination with two expert committees to arrive at the English scale version, aiming to obtain at least structural equivalence. We utilize a bilingual sample (N = 76) as well as monolingual samples from the US (N = 174) and…
Increased airway inflammatory cells in endurance athletes: what do they mean?
2003
Background Inflammatory cells are increased in the airways of end urance athletes, but their role in causing exercise-induced respiratory symptoms and bronchoconstriction, or their possible long-term consequences, are uncertain. Aim To put the results of athlete studies in perspective, by analysing the pathogenesis of airway cell changes and their impact on respiratory function. Results Athletes of different endurance sports at rest showed increased airway neutrophils. Elite swimmers and skiers also showed large increases in airway eosinophils and lymphocytes, possibly related to chronic, exercise-related exposure to irritants or cold and dry air, respectively. Post-exercise studies reporte…
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…
Real And Positive Filter Based On Circular Harmonic Expansion
1989
A real and positive filter for pattern recognition is presented. The filter, based on the circular harmonic (CH) expansion of a real function, is partially rotation invariant. As it is real and positive, the filter can be recorded on a transparency as an amplitude filter. Computer simulations of character recognition show a partial rotation invariance of about 40°. Optical experiments agree with these results and with acceptable discrimination between different characters. Nevertheless, due to experimental difficulties, the method is onerous for use in general pattern recognition problems.
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 …
TH-C-AUD A-07: Evaluation of the Correction Factor Due to the Lack of Full Scatter Conditions in Cs-137 and Ir-192 Brachytherapy Dosimetric Studies
2008
Purpose: Use of a finite phantom to derive dose rate distributions around brachytherapysources implies a lack of backscattering material near the phantom periphery. Conventional planning algorithms and newly‐developed 3D correction algorithms are based on physics data under full scatter conditions. Presently, most published Monte Carlodosimetric studies have been obtained using either a spherical phantom (15cm in radius) or a cylinder phantom (40×40cm2). The study objective was to derive a simple relationship to correlate the radial dose function, g(r), obtained for each one of these phantoms to that obtained for an unbounded phantom. Method and Materials: Assuming bare point sources of 137…
An algorithm for earthquakes clustering based on maximum likelihood
2007
In this paper we propose a clustering technique set up to separate and find out the two main components of seismicity: the background seismicity and the triggered one. We suppose that a seismic catalogue is the realization of a non homogeneous space-time Poisson clustered process, with a different parametrization for the intensity function of the Poisson-type component and of the clustered (triggered) component. The method here proposed assigns each earthquake to the cluster of earthquakes, or to the set of independent events, according to the increment to the likelihood function, computed using the conditional intensity function estimated by maximum likelihood methods and iteratively chang…
Semi-Supervised Remote Sensing Image Classification based on Clustering and the Mean Map Kernel
2008
This paper presents a semi-supervised classifier based on the combination of the expectation-maximization (EM) algorithm for Gaussian mixture models (GMM) and the mean map kernel. The proposed method uses the most reliable samples in terms of maximum likelihood to compute a kernel function that accurately reflects the similarity between clusters in the kernel space. The proposed method improves classification accuracy in situations where the available labeled information does not properly describe the classes in the test image.