Search results for "Modelli"
showing 10 items of 1866 documents
Numerical and experimental study of liquid metal stirring by rotating permanent magnets
2018
In this work, we study liquid gallium stirring by rotating permanent magnets. We demonstrate possibility of easily creating different flow patterns by rotating permanent magnets, which can be industrially important for controlling heat and mass transfer processes in the system. Unlike the typical approach of simulating magnet rotation as a transient problem and time-averaging the Lorentz forces, we solve the magnet rotation as a harmonic (frequency domain) problem, which leads to forces equal to time-averaged ones and decreases the simulation time considerably. Numerical results are validated using qualitative flow structure results from the neutron radiography visualization of tracer parti…
Tectonique et architecture des bassins intracratoniques Paléozoïques : impact sur l’enregistrement sédimentaire et la géométrie des réservoirs associ…
2019
The Paleozoic Saharan platform including the peri-Hoggar Basins (i.e. Murzuq, Illizi, Mouydir, Ahnet, Reggane and Tim Mersoï basins) are defined as intracraonic basins. Their histories have been dominated by slow long-wavelength vertical motions leading to overall low subsidence rate (i.e ca. 10 m/Ma to 50 m/Ma) and accumulation of an extensive cover of platformal sediments (i.e. shallow deposits environments), rhythmed by pulsatile periods of increasing and decreasing rate probably triggered by regional geodynamic events. The vertical motions of the platform produced several arches also called domes, swells, highs, ridges (e.g. the Tihemboka, Amguid El Biod, Arak-Foum Belrem and Azzel Matt…
Plasma Pro-C3 (N-terminal type III collagen propeptide) predicts fibrosis progression in patients with chronic hepatitis C.
2014
BACKGROUND & AIMS: Fibrogenesis results in release of certain extracellular matrix protein fragments into the circulation. We evaluated the diagnostic and prognostic performance of two novel serological markers, the precisely cleaved N-terminal propeptide of type III collagen (Pro-C3) and a peptide of helical collagen type III degradation (C3M), in chronic hepatitis C (CHC) patients. METHOD: Pro-C3 and C3M were measured by ELISA in plasma from CHC patients (n = 194) from a prior phase II antifibrotic trial (NCT00244751). Plasma samples and paired liver biopsies were obtained at baseline and after 1-year. Patients were stratified according to Ishak stages 2-4. Internal cross-validation w…
Analysis of a strip loop antenna located on the surface of an open cylindrical waveguide filled with a resonant magnetoplasma
2013
The electrodynamic characteristics of a circular loop antenna located on the surface of an open waveguide in the form of an axially magnetized plasma column are studied using the integral equation method. The current distribution and the input impedance of the antenna excited by a time-harmonic external voltage are obtained in closed form for the case where the plasma inside the column is resonant.
Physico-chemical evolution of low-pH cements : influence of the temperature and the retention mechanisme of alkalins
2010
Because of their high alkalinity, Portland cement (OPC)-based materials may have deleterious effects in an underground waste repository. A solution would be to use low-alkalinity cements (also referred as low-pH cements) generating interstitial solutions with a reduced pH (11 instead of 13.5 for OPC), and thus showing an improved chemical compatibility with the repository environment. In this work, the investigated formulations were based on binary (OPC / silica fume) or ternary (OPC / silica fume / slag or fly ash) blends, with high substitution levels of CEM I (from 30% to 80%). This research project met two main objectives: (i) study the chemical evolution of low-pH cements at 50°C or 80…
Perceived Value in Tourism: A PLSPM Approach
2015
This paper examines the concept of perceived value in rural tourism referred to the specific context of Sicilian holiday farms. Herein main dimensions composing the rural tourist perceived value (RTPV) are discussed. Using Partial Least Squares Path Modelling (PLSPM) –a statistical technique especially suitable for exploratory purposes with small samples – a theoretical structural model of the multidimensional structure of RTPV is tested and the causal relationships among RTPV and its dimensions (Functional, Convenience, Emotional and Educational) and among RTPV and tourists’ satisfaction and loyalty are explored. Results from a field survey on 350 tourists give a contribution in terms of i…
How upper secondary students solve algebraic word problems in the area of mathematical modelling : A case study of one group of Norwegian students
2019
Masteroppgave matematikkdidaktikk MA500 - Universitetet i Agder 2019 For å imøtekomme nye utfordringer på skolen, i jobb og i livet, kan elever ha behov for åtilpasse og utvide den matematikken de kan. Dette krever at elever evner, i noen grad, åsette skolematematikken i forbindelse med hverdagslige kontekster og motsatt. Matema-tisk modellering er en av de hensiktsmessige mediene for å støtte sammenhengen mellomskolematematikken og virkeligheten. Forskning har vist at det er en sterk tilbøyelighet ipensumet mot matematisk modellering og at i stedet høynivå matematikk er ansett somviktig, mest på videregående nivå. Igjen, forskning viser at elever har større utfordringermed abstrakte (fakta…