Search results for "Experimental Data"
showing 10 items of 137 documents
A Temperature Dependent Non-Linear Inductor Model for a DC/DC Boost Converter
2018
This paper is focused on the use of non-linear inductors in DC/DC switching converters, as well as their behaviour due to changes in current and temperature. The model of an inductor is set up on the basis of experimental data, which are automatically acquired by a virtual instrument; from those data, a polynomial curve describing the inductance variations is obtained. The analysis of the converter, performed by including the proposed model, is validated by experimental tests.
A Problem Based Approach to Elastic Wave Propagation: The Role of Constraints
2009
A problem-based approach to the teaching of mechanical wave propagation, focused on observation and measurement of wave properties in solids and on modelling of these properties, is presented. In particular, some experimental results, originally aimed at measuring the propagation speed of sound waves in metallic rods, are used in order to deepen the role of constraints in mechanical wave propagation. Interpretative models of the results obtained in the laboratory are built and implemented by using a well-known simulation environment. The simulation results are, then, compared with experimental data. The approach has been developed and experimented in the context of a workshop on mechanical …
A critical analysis of the advanced generalized theory: Applicability and applications
2006
Abstract A recent series of theoretical works (“advanced generalized theory”) has been proposed and applied to the analysis of hydrogen lines, particularly H α in plasmas. The “advanced generalized theory” (AGT) [JQSRT 1994;51:129, Phys Rev E 1999;60:R2480, JQSRT 2000; 65:405] is critically examined, both theoretically and in applications to the analysis of experimental data. A number of serious flaws are exposed and discussed. The major flaws include using an inconsistent perturbation theory and erroneous Weisskopf radius-type arguments to access dynamic behavior. Further, the results derived from calculations using the theory are in disagreement with both exact analytic results and benchm…
SU-E-T-237: Monte Carlo Dosimetric Characterization of the Mobetron Mobile Linac
2014
Purpose: The aim of this work is to characterize dosimetrically a clinical intraoperative electron beam accelerator, Mobetron (IntraOp Medical, Inc.) in clinical use in our Hospital. Once this first step is completed our purpose is to evaluate shielding requirements for such a device by preparing adequate phase space files. Methods: It is known that electron beam simulation parameters required for state-of-the-art Monte Carlo codes to obtain a good match with measured data, like the mean energy or the FWHM, may not be code-independent due to the different set of process simulated and formalisms involved. Then, to cross-check our results against any issue in the simulation we have compared e…
Entropic approach to estimate the mean flow velocity: experimental investigation in laboratory flumes
2015
The paper deals with the linear entropic relationship between the maximum velocity, u max , and the mean flow velocity, u m , through a dimensionless parameter Φ(M), in open-channel flow. The analysis is conducted with the aid of experimental data collected in straight laboratory flumes under different bed and side-walls roughness conditions. In particular, rough/vegetated beds and smooth/rough side-walls conditions have been investigated. The results show that, in the investigated conditions (with exception of low-submergence vegetated bed—h/k v < 2), Φ(M) can be assumed equal to a value that is very close to that found in natural channels. This demonstrates that Φ(M) is able to implicitl…
Damage accumulation in a carbon/epoxy composite : Comparison between a multiscale model and computed tomography experimental results
2012
International audience; High-resolution computed tomography has been carried out for carbon/epoxy laminates loaded in situ to failure. The experimental data allows major damage mechanisms to be quantified in 3D, in an unambiguous and mechanically representative way, where previous experimental analysis is limited. A multi-scale model that predicts damage accumulation in tensile loaded composites is compared to the experimental analysis, to validate the underpinning assumptions within the model and overall performance. The model considers the random nature of fibre-strengths, stress transfer resulting from fibre breaks, fibre/matrix debonding and viscosity of the matrix. Assumptions within t…
Data Treatment and Error Analysis in Kinetics
2000
Methods of data treatment in kinetics are reviewed from a practical viewpoint. The equations to describe the kinetics of chemical reactions and the methodology to obtain the models are presented. Moreover, the integration methods that are needed for the simulation of complex reactions are explained, from the simple first-order reaction to the complex general mechanism. However, it is essential to know the main sources of error in data treatment in order to reduce their effects on the results. Stress is put on the analysis of the errors due to the simplification of complex models. The different factors that influence the kinetics of the reaction are reviewed. How to take advantage of the kin…
The use of a European coinage alloy to compare the detection limits of mobile XRF systems. A feasibility study
2007
The investigation of archaeological and historical materials makes use of techniques that, though borrowed from other fields of research and industrial production, frequently have to be 're-invented' because of peculiar characteristics of the analysed objects. Artistic relevance, limited movability, compositional and structural heterogeneity radically change the experimental approach and often require ad hoc designed equipment. These considerations also apply to x-ray fluorescence, especially regarding mobile systems. The extensive development and use of mobile spectrometers has produced an extremely diversified context and created the need for common criteria to evaluate their performances…
Tomographic image of the proton
2016
We determine, based on the latest experimental Deep Virtual Compton Scattering experimental data, the dependence of the spatial size of the proton on the quark's longitudinal momentum. This results in a three-dimensional momentum-space image and tomography of the proton.
An experimental approach to efficiency calibration for gamma-ray spectrometric analysis of large air particulate filters
2013
Abstract A full-energy-peak efficiency (FEPE) calibration procedure for gamma-ray spectrometric analysis of air particulate samples collected on large filters is described herein. The experimental results are obtained for an unconventional measurement geometry, termed a “packet-sample”. The sample is obtained from a large cellulose filter (45 cm×45 cm) used to collect air particulate samples that is resized to dimensions suitable for spectrometric measurements (6 cm×6 cm×0.7 cm). To determine the FEPEs, many standards were created, i.e., some filters containing a small amount of ThO 2 and others containing a known amount of KCl. Efficiency curves obtained through best fits to experimental d…