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Time-frequency analysis combining wavelets and the envelope technique for fault identification in rotary machines
(2013-03-18)
Nowadays the method based on demodulation by envelope finds wide application in industry as a technique for evaluation of bearings and other components in rotating machinery. In recent years the application of Wavelets for ...
An alternative procedure to decrease the dimension of the frequency dependent modal transformation matrices: Application in three-phase transmission lines with a vertical symmetry plane
(2006-12-01)
The objective of this paper is to show an alternative representation in time domain of a non-transposed three-phase transmission line decomposed in its exact modes by using two transformation matrices. The first matrix is ...
Analysis of the Frequency Dependent Lumped Parameter Transmission Line Model
(2020-11-12)
An accurate transmission line model must consider the frequency-dependence of the longitudinal parameters. In this context, the lumped parameter model (LPM), despite its well-known limitations, had been largely used to ...
Patellofemoral pain syndrome: Electromyography in a frequency domain analysis
(2011-12-29)
The Patellofemoral Pain Syndrome (PFPS), has a multifactorial etiology and affects approximately 7 to 15% of the population, mostly women, youth, adults and active persons. PFPS causes anterior or retropatelar pain that ...
Corona effect in frequency dependent transmission line models
(2008-12-01)
The inclusion of the corona effect in a frequency dependent transmission line model is proposed in this paper. The transmission line is represented through a cascade of π circuits and the frequency dependence of the ...
Transient Responses on Transmission Lines Located above Frequency-Dependent Soil with Variable Water Content
(2021-01-01)
This paper investigates the influence of frequency-dependent soil parameters with variable water content in the transient responses of single-circuit three-phase transmission line (TL) subjected to lightning subsequent ...
Dynamic analysis of a new piezoelectric flextensional actuator using the J1-J4 optical interferometric method
(2005-12-01)
Piezoelectric actuators are widely used in positioning systems which demand high resolution such as scanning microscopy, fast mirror scanners, vibration cancellation, cell manipulation, etc. In this work a piezoelectric ...
Damage Detection Based on Electromechanical Impedance Principle and Principal Components
(2014-01-01)
This paper presents a novel time domain approach for Structural Health Monitoring (SHM) systems based on Electromechanical Impedance (EMI) principle and Principal Component Coefficients (PCC), also known as loadings. ...
A procedure to estimate parameters of a line segment taking into account its representation through π circuits: Theoretical development
(2006-12-01)
The objective of this paper is to show an alternative methodology to estimate per unit length parameters of a line segment of a transmission line. With this methodology the line segment parameters can be obtained starting ...
Modeling for performance analysis of electromagnetic zero-sequence suppressor
(2010-12-30)
The purpose of this work is to present a frequency domain model to demonstrate the operation of an electromagnetic arrangement for controlling the injection of zero-sequence currents in the electrical system. Considering ...