Results 21 to 30 of about 242 (108)

Investigative Study of Vertical Electrodes Encased in Concrete/Mortar with Various Sizes of Air Voids

open access: yesEnergies, 2021
Ionisation can occur in the soil when high impulse currents are subjected to grounding systems. This occurrence is generated by a difference in the dielectric strength value between the soil and air voids.
Hanis Hamizah Hizamul-Din   +3 more
doaj   +1 more source

Evaluation of Respiratory Impedance in Asthma and COPD by an Impulse Oscillation System

open access: yesInternal Medicine, 2010
The purpose of this study was to clarify the differences in physiological properties of the airways between asthma and COPD using an impulse oscillation system (IOS).Subjects comprised 95 stable COPD patients, 52 never-smoker asthma patients and 29 healthy never-smokers >60 years old, all matched for age, in whom respiratory impedance was examined by ...
Kanda, Shintarou   +5 more
openaire   +3 more sources

A Study on Frequency Response Functions in Pavement Engineering

open access: yesThe Baltic Journal of Road and Bridge Engineering, 2023
Mechanical impedance (MI) defines the ability of a system to vibrate as a consequence of force application. In the recent years, the correlation of this parameter with tire-road noise and other characteristics has gained certain attention.
Filippo G. Pratico   +3 more
doaj   +1 more source

Impulse Characteristics of Various Soil-Enhancement Material Mixtures

open access: yesApplied Sciences
Many studies have demonstrated that a reduction in ground impedance value occurs under high-impulse current magnitudes, due to the ionisation process in soil.
Fazlul Aman   +3 more
doaj   +1 more source

Impedance and impulse response measurements using low-cost components [PDF]

open access: yesThe Journal of the Acoustical Society of America, 1982
A thin 27-mm-o.d. disk transducer (from Radio Shack 273-060 signaler) is RTV sealed to the end of a measurement tube whose 15 mm i.d. not only approximates the transducer disk's nodal circle but also the i.d. of a clarinet, sax, or trumpet mouthpiece. A 10-mm-o.d.
M. I. Ibisi, A. H. Benade
openaire   +1 more source

Parameter Estimation of a Grid-Tied Inverter Using In Situ Pseudo-Random Perturbation Sources

open access: yesEnergies, 2023
Inverters are playing an increasingly important role in the electrical utility grid due to the proliferation of renewable energy sources. Obtaining inverter models with accurate parameters is, therefore, essential for grid studies and design.
Ian Paul Gerber   +2 more
doaj   +1 more source

Measurement of impulse noise propagation over natural impedance surfaces [PDF]

open access: yesThe Journal of the Acoustical Society of America, 1985
The peak sound pressure level decay with distance of the impulse noise from hand grenade simulators has been measured over the following types of surfaces: water, swamp, rocky ground with small bushes, dead grass with sparse snow cover, and dense evergreen forest. The ground impedance is estimated for each surface using the calculation of R. Raspet. H.
Nelson Lewis, Richard Raspet
openaire   +1 more source

Reference values for respiratory system impedance using impulse oscillometry in healthy preschool children [PDF]

open access: yesKorean Journal of Pediatrics, 2011
PurposeThe normal values for lung resistance and lung capacity of children, as determined by impulse oscillometry (IOS), are different for children of different ethnicities.
Jye Hae Park   +8 more
doaj   +1 more source

Chromaticity and wakefield effect on the transverse motion of longitudinal bunch slices in the Fermilab Tevatron

open access: yesPhysical Review Special Topics. Accelerators and Beams, 2008
The transverse turn-by-turn evolution of a bunch slice after an impulse kick is examined considering chromatic and impedance effects. It is found that by fitting the envelope of the beam slice motion to simulated data the strength of the resistive wall ...
V. H. Ranjbar, P. Ivanov
doaj   +1 more source

Review of Local Network Impedance Estimation Techniques

open access: yesIEEE Access, 2020
As a result of increasing variability of network impedance, interest in impedance estimation techniques is growing. This review contextualises local impedance estimation techniques by providing a historical prospective on the uses of these techniques ...
Mathieu Kervyn De Meerendre   +5 more
doaj   +1 more source

Home - About - Disclaimer - Privacy