Search results for "measuring"
showing 10 items of 110 documents
A Multipurpose Instrument To Measure the Vitreous Properties of Charged Colloidal Solids
2001
We present a new high-precision light-scattering setup to study the properties of colloidal solids. It combines static light scattering, dynamic light scattering, and torsional resonance spectroscopy with a flexible and reliable preparational procedure. All three experiments can be performed quasi-simultaneously on the same mechanically undisturbed sample. Thus, unequivocal identification of glassy behavior in a comprehensive characterization dependent on interaction parameters becomes possible. A detailed description of the mechanics is given. We thoroughly tested the new apparatus on dilute colloidal samples and against commercial reference instruments. We performed a first systematic ser…
A commentary on the Special Issue “Innovations in measuring and fostering mathematical modelling competencies”
2021
This is a commentary on the ESM 2021 Special Issue on Innovations in Measuring and Fostering Mathematical Modelling Competencies. We have grouped the ten studies into three themes: competencies, fostering, and measuring. The first theme and the papers therein provide a platform to discuss the cognitivist backgrounds to the different conceptualizations of mathematical modelling competencies, based on the modelling cycle. We suggest theoretical widening through a competence continuum and enriching of the modelling cycle with overarching, analytic dimensions for creativity, tool use, metacognition, and so forth. The second theme and the papers therein showcase innovative ideas on fostering an…
Compaction of Open-Graded HMAs Evaluated by a Fuzzy Clustering Technique
2015
The aim of this paper is the proposal of an expeditious procedure to be used during the execution of an asphalt layer for improving the compaction task. This procedure, based on a fuzzy clustering technique, starts from the knowledge of some information recorded by ordinary measuring instruments and provides an aid to the decision-maker on the number of roller passes needed to achieve a specific density at a certain temperature. This result can be deduced with great rapidity during the paving operations on site without waiting for the time spent in the core extraction and in the subsequent laboratory analysis. In this way it is possible to identify more precisely which aspects of the execut…
Los Estereotipos de género en las producciones audiovisuales: diseño y validación de la tabla de análisis EG_5x4
2022
Los productos culturales de la educación no formal, y en concreto los difundidos por televisión y plataformas streaming, incluidas no ficción y animación infantil, proponen entre sus figuraciones personajes estereotipados en su construcción de género. Según investigaciones previas, identificarlos y combatirlos favorece la erradicación de ideas sexistas relacionadas con violencias machistas. Por ello, el objetivo que se planteó fue diseñar y validar una tabla de análisis de estereotipos sexuales presentes en cualquier producto audiovisual. El proceso siguió un protocolo de 3 fases (Garrido et al., 2015): 1) Se revisó la literatura publicada, se extrajeron rasgos relacionados con estereotipos…
Status of the EDELWEISS experiment
1999
The Edelweiss Dark Matter Experiment is installed in the Modane Underground Laboratory since 1994. In 1997 the first detector of a 70 g heat and ionization Ge low-temperature detector built by the collaboration showed its discrimination capabilities. During the last two years the installation was upgraded, and a new generation of 70 g Ge detectors is operational. The detector environment is drastically controlled to avoid radioactive contamination. A test run with two new 70 g detectors shows a reduction by a factor of ten in the background level before 7-ray rejection which is now around 2 events/kg/keV/day. Three 320 g Ge cryogenic detectors have been constructed and are now being tested …
Electromagnetic and ultrasonic investigations on a Roman marble slab
2011
The archaeological museum of Rome asked our group about the physical consistency of a marble slab (second to third century AD) that recently fell during its travel as part of an exhibition. We decided to use different methodologies to investigate the slab: namely a pacometer (Protovale Elcometer) to individuate the internal coupling pins, and ground-penetrating radar (GPR) (2000 MHz) and ultrasonic (55 kHz) tomographic high-density surveys to investigate the internal extension of all the visible fractures and to search for the hidden ones. For the ultrasonic data, tests were carried out to optimize the inversion parameters, in particular the cell dimensions. Surely, the choice of cell size …
Recent developments and future trends in solid phase microextraction techniques towards green analytical chemistry.
2013
Solid phase microextraction find increasing applications in the sample preparation step before chromatographic determination of analytes in samples with a complex composition. These techniques allow for integrating several operations, such as sample collection, extraction, analyte enrichment above the detection limit of a given measuring instrument and the isolation of analytes from sample matrix. In this work the information about novel methodological and instrumental solutions in relation to different variants of solid phase extraction techniques, solid-phase microextraction (SPME), stir bar sorptive extraction (SBSE) and magnetic solid phase extraction (MSPE) is presented, including prac…
Low stiffness variation in structural systems: identification and localization
2008
When a very low damage occurs, the undamaged structural response totally overlaps the damaged one either in time domain or in frequency domain; on the other hand, by considering some characteristics of the analytical signal, such as the phase, it has been possible to develop a damage identification procedure that allows the identification and localization of damage even if the structure experiences multiple damages at the same time. This procedure is also robust with respect to the presence of measuring noise. In order to assess the validity of the proposed damage identification procedure, numerical applications on single degree of freedom and 2 DOF and 4 DOF are presented using data record…
A Monte Carlo Method for the Auto-Evaluation of the Uncertainties in the Analog-to-Digital Conversion-Based Measurements
2004
This paper concerns with the measurement uncertainty estimation in the analog‐to‐digital conversion‐based instruments. By using an ad hoc developed software tool, the Monte Carlo method is applied in order to assess the uncertainties associated with the measurement results, overcoming the possible inapplicability of the pure theoretical approach prescribed in the ISO – “Guide to the Expression of Uncertainty in Measurement”. By implementing the software tool in the measurement instruments, the proposed approach can be utilized in order to make the instrument itself able to auto‐estimate the measurement uncertainties.
Phasor total unbalance power: Formulation and some properties
2007
Unbalance power has been used to quantify unbalance phenomenon effects in the electric power systems for a long time. Expressions of this power developed by some different theories only give the value of its module. Therefore, total unbalance power values in electric power systems cannot be obtained by the unbalance power values of each of their loads. For that, it is necessary to express the unbalance power as a complex number. In this paper the unbalance power is expressed in phasor notation and some of their properties are described, applied to electric systems with balanced voltages. Results are verified by simulation and also practical comparative experiences are realized in actual ins…