Increase High Frequency Impedance of Ferrite Toroid Inductors Based on Electromagnetic Energy Analysis

2019 ◽  
Author(s):  
Yiming Li ◽  
Juntao Yao ◽  
Shuo Wang
Keyword(s):  
High Frequency ◽  
Energy Analysis ◽  
Electromagnetic Energy

scholarly journals Location of agate geodes in Permian deposits of Simota gully using the GPR

2021 ◽  
Author(s):  
Michał Mierczak ◽  
Jerzy Karczewski
Keyword(s):  
Signal Processing ◽  
High Frequency ◽  
Electromagnetic Energy ◽  
Reflection Coefficients ◽  
Electric Permittivity ◽  
Pyroclastic Deposits ◽  
High Attenuation ◽  
Subsurface Geology ◽  
Study Test

AbstractThe article describes the establishment of the location of agate geodes using the GPR method in the area of the Simota gully (Lesser Poland Voivodeship). Agates (a multicolored variety of gemstone of chalcedony group) have multifaceted values that informed their study. Traditional methods of geode location are less reliable, hence the attempt to use the GPR method. Measurements were taken at two study test sites with subsurface geology of weathered melaphyre and pyroclastic deposits using a GPR system (ProEx). A high-frequency antenna (1.6 GHz) was used along with the pre-established profiles of lengths of 6-m and 10-cm intervals. Furthermore, simple soil tests using the soil sampler tool were made prior to the GPR measurement. The GPR results show significant high attenuation of the electromagnetic energy interpreted to be due to clay components of the regolith. Advanced signal processing procedures (such as the attribute of the signal) were used on the data for better enhancement that aided interpretation. Other anomalies depicted on the radargrams were thought to be the presence of roots, pieces of melaphyres-targeted agates. Furtherance to ascertain the reflection coefficients as recorded on the GPR data, in situ samples (root pieces, melaphyres, agates) taken were tested in the laboratory for electric permittivity property. Based on the interpretation results, several agate geodes were dug out from the ground.

Power Flow and Energy Sharing between an Oscillator and a Continuous Receiver Structure

2011 ◽  
Vol 189-193 ◽  
pp. 1914-1917
Author(s):  
Lin Ji
Keyword(s):  
High Frequency ◽  
Power Flow ◽  
Energy Analysis ◽  
Statistical Energy Analysis ◽  
Coupled Subsystems ◽  
Modal Density ◽  
Vibration Problems ◽  
Energy Sharing ◽  
High Modal Density ◽  
Vibration Modeling

A key assumption of conventional Statistical Energy Analysis (SEA) theory is that, for two coupled subsystems, the transmitted power from one to another is proportional to the energy differences between the mode pairs of the two subsystems. Previous research has shown that such an assumption remains valid if each individual subsystem is of high modal density. This thus limits the successful applications of SEA theory mostly to the regime of high frequency vibration modeling. This paper argues that, under certain coupling conditions, conventional SEA can be extended to solve the mid-frequency vibration problems where systems may consist of both mode-dense and mode-spare subsystems, e.g. ribbed-plates.

Realization of a Minimum-Order Power Flow Model and SEA Model Updating Using Time Domain Measurements

2000 ◽  
Author(s):  
Joseph W. Gregory ◽  
Richard F. Keltie ◽  
F. Donald Caulfield
Keyword(s):  
Time Domain ◽  
High Frequency ◽  
Power Flow ◽  
Flow Model ◽  
Energy Analysis ◽  
Model Updating ◽  
Order Model ◽  
Minimum Order ◽  
First Order ◽  
Power And Energy

Abstract A time domain method for identifying middle to high frequency system parameters from sound and vibration measurements is presented. This work is part of a beginning investigation with an objective of enhancing experimental Statistical Energy Analysis (SEA). Thus far, it is seen that a state space realization method can be used to identify a first order power flow model from measured transient power and energy data. Specifically, the Eigensystem Realization Algorithm (ERA) is observed to accurately identify a minimum order model for a simple system. Additionally, it is found that the identified model can be used to improve an existing SEA model of the system.

On a structural–acoustic panel cavity modelling in the mid-high frequency domain

2011 ◽  
Vol 226 (4) ◽  
pp. 900-912 ◽  
Author(s):  
M de Rochambeau ◽  
M Ichchou ◽  
B Troclet
Keyword(s):  
Finite Element ◽  
Frequency Domain ◽  
High Frequency ◽  
Energy Analysis ◽  
Coupled System ◽  
Element Model ◽  
Statistical Energy Analysis ◽  
Hybrid Strategy ◽  
Interaction Modelling

This article presents a fluid–structure interaction modelling, based on a coupling between component mode synthesis or finite element and statistical energy analysis (SEA). The hybrid strategy is applied on a panel–cavity coupled system using a modal analysis with uncoupled modes of the subsystems and through a finite element model of the coupled system. The determination of the energy transfer parameters is then considered. The hybrid SEA model is then validated in the high-frequency domain by comparison with an SEA model. Finally, a parametric survey is offered through the established modelling and conclusions on its validity domain are drawn.

Wave intensity analysis of high frequency vibrations

1994 ◽  
Vol 346 (1681) ◽  
pp. 489-499 ◽  
Keyword(s):  
High Frequency ◽  
Energy Analysis ◽  
Dynamic Stiffness ◽  
Intensity Analysis ◽  
Coupling Loss ◽  
Plate Structures ◽  
Vibrational Response ◽  
Directional Filtering ◽  
Alternative Approach ◽  
High Frequency Vibrations

In the statistical energy analysis (SEA) approach to high frequency dynamics it is assumed that the vibrational wavefield in each component of an engineering structure is diffuse. In some instances the directional filtering effects of structural joints can lead to highly non-diffuse wavefields, and in such cases sea will yield a very poor estimate of the vibrational response. An alternative approach is presented here in which the directional dependency of the vibrational wavefield in each component is modelled by using a Fourier series. It is shown that, if required, the resulting energy balance equations may be cast in the form of conventional SEA with the addition of ‘non-direct’ coupling loss factors. The method is applied to the bending and in-plane vibrations of various plate structures and a comparison is made with exact results yielded by the dynamic stiffness method. A significant improvement over conventional SEA is demonstrated.

Statistical Energy Analysis for Electronic Equipment

1991 ◽  
Vol 113 (3) ◽  
pp. 322-325
Author(s):  
L. Lu
Keyword(s):  
Mathematical Model ◽  
High Frequency ◽  
Vibration Analysis ◽  
Energy Analysis ◽  
Element Model ◽  
Electronic Equipment ◽  
System Response ◽  
Statistical Energy Analysis ◽  
Simple Mathematical Model ◽  
Good Agreement

Vibration response of electronic equipment analyzed by a simple mathematical model or a finite element model can only provide a limited system response calculation. Application of the Statistical Energy Analysis (SEA) was extended to the calculation of the vibrations of individual components. In order to demonstrate the applicability of SEA to instrumentation vibration analysis at high frequency ranges, an 8-component electronic box was chosen for test and analysis. There was good agreement between tested and analytical results in the frequency averaged sense.

Sign in / Sign up

Export Citation Format

Share Document