Search results for "Measurement"
showing 10 items of 2918 documents
A symmetric nonlocal damage theory
2003
The paper presents a thermodynamically consistent formulation for nonlocal damage models. Nonlocal models have been recognized as a theoretically clean and computationally efficient approach to overcome the shortcomings arising in continuum media with softening. The main features of the presented formulation are: (i) relations derived by the free energy potential fully complying with nonlocal thermodynamic principles; (ii) nonlocal integral operator which is self-adjoint at every point of the solid, including zones near to the solid's boundary; (iii) capacity of regularizing the softening ill-posed continuum problem, restoring a meaningful nonlocal boundary value problem. In the present app…
Can hydrophobic interactions be correctly reproduced by the continuum models?
1996
The ability of the continuum models to describe hydrophobic interactions is investigated. In this work we have studied the interactions between two methane molecules in aqueous solution by means of a continuum model. The resulting potential of mean force is in good agreement with those obtained using Monte Carlo and molecular dynamics techniques. The three energy contributions appearing in the continuum energy partition (electrostatic, dispersion−repulsion, and cavitation) have been analyzed. The cavitation free energy plays the most important role of the three, determining the existence of an energy barrier between the contact minimum and the separated methane monomers. This barrier, which…
The Reduction of Dimension in the Study of Economic Growth Models
2002
We examine the dimension reduction method and prove that it could be misleading if we try to get some insight into the dynamics of the original system from the dynamics of the transformed system alone. The reduced system seemingly may give rise to a continuum multiplicity of steady states when, actually, it does exist a unique and isolated steady state or even it does not exist a steady state at all. We show how the dynamics for the primary variables that is recovered from the solution to the reduced system may be refuted by solving the original one. In our opinion there is no alternative because nothing can be regarded as a close substitute for the study of the original system. Although th…
THE EXPRESSION OF EVIDENTIALITY IN SPOKEN AND WRITTEN TEXTS: EMPIRICAL APPROACHES TO ROMANCE LANGUAGES
2020
Evidentiality is a grammatical category that encodes information source as its primary meaning. The information can be: acquired through direct perception, reported by others (hearsay) or inferred by the speaker upon considering the information that is available. Languages with an evidential grammatical category have morphemes with a primary evidential value (Aikhenvald 2004). Nevertheless, Romance languages, like many other languages, have a tense- modal system and lack an evidential grammatical category, instead of which several lexical units or certain constructions convey information source. This special issue is devoted to some of those items, such as modal adverbs, evidential meanings…
The functional-psychological continuum in the cognitive image of a destination: A confirmatory analysis
2009
Abstract This paper analyses the cognitive component of the image of a destination from a dual perspective. Firstly, we study its composition by positing three positions on a continuum: functional, mixed and psychological, which are analysed using confirmatory factor analysis. Secondly, we study the influence of these components on tourists' overall image of the destination and on their future behaviour intentions, using structural equation analysis. The results show that the psychological and functional components exercise the greatest influence on the overall image of the destination. Overall image was found to influence future behaviour intentions consistently, while the functional compo…
A Virtual Tool for Load Flow Analysis in a Micro-Grid
2020
This paper proposes a virtual tool for load flow analysis in energy distribution systems of micro-grids. The solution is based on a low-cost measurement architecture, which entails low-voltage power measurements in each secondary substation and a voltage measurement at the beginning of the medium voltage (MV) feeder. The proposed virtual tool periodically queries these instruments to acquire the measurements. Then, it implements a backward&ndash
Sensor Fusion Localization and Navigation for Visually Impaired People
2018
In this paper, we present an innovative cyber physical system for indoor and outdoor localization and navigation, based on the joint utilization of dead-reckoning and computer vision techniques on a smartphone-centric tracking system. The system is explicitly designed for visually impaired people, but it can be easily generalized to other users, and it is built under the assumption that special reference signals, such as colored tapes, painted lines, or tactile paving, are deployed in the environment for guiding visually impaired users along pre-defined paths. Differently from previous works on localization, which are focused only on the utilization of inertial sensors integrated into the s…
A General and Accurate Measurement Procedure for the Detection of Power Losses Variations in Permanent Magnet Synchronous Motor Drives
2020
The research of innovative solutions to improve the efficiency of electric drives is of considerable interest to challenges related to energy savings and sustainable development. In order to successfully validate the adoption of new and innovative software or hardware solutions in the field of electric drives, accurate measurement procedures for either efficiency or power losses are needed. Moreover, high accuracy and expensive measurement equipment are required to satisfy international standard prescriptions. In this scenario, this paper describes an accurate measurement procedure, which is independent of the accuracy of the adopted instrumentation, for the power losses variations involved…
A New Coupling Solution for G3-PLC Employment in MV Smart Grids
2019
This paper proposes a new coupling solution for transmitting narrowband multicarrier power line communication (PLC) signals over medium voltage (MV) power lines. The proposed system is based on an innovative PLC coupling principle, patented by the authors, which exploits the capacitive divider embedded in voltage detecting systems (VDS) already installed inside the MV switchboard. Thus, no dedicated couplers have to be installed and no switchboard modifications or energy interruptions are needed. This allows a significant cost reduction of MV PLC implementation. A first prototype of the proposed coupling system was presented in previous papers: it had a 15 kHz bandwidth useful to couple sin…
The ACRIDICON-CHUVA campaign: Studying tropical deep convective clouds and precipitation over Amazonia using the new German research aircraft HALO
2016
Abstract Between 1 September and 4 October 2014, a combined airborne and ground-based measurement campaign was conducted to study tropical deep convective clouds over the Brazilian Amazon rain forest. The new German research aircraft, High Altitude and Long Range Research Aircraft (HALO), a modified Gulfstream G550, and extensive ground-based instrumentation were deployed in and near Manaus (State of Amazonas). The campaign was part of the German–Brazilian Aerosol, Cloud, Precipitation, and Radiation Interactions and Dynamics of Convective Cloud Systems–Cloud Processes of the Main Precipitation Systems in Brazil: A Contribution to Cloud Resolving Modeling and to the GPM (Global Precipitatio…