Fourier energy analysis of Kikuchi patterns for investigation of defect system of diamond crystals

The energy analysis of electrons scattered by a specimen in a scanning transmission electron microscope can improve contrast as well as aid in chemical identification. In so far as energy analysis is useful, one would like to be able to design a spectrometer which is tailored to his particular needs. In our own case, we require a spectrometer which will accept a parallel incident beam and which will focus the electrons in both the median and perpendicular planes. In addition, since we intend to follow the spectrometer by a detector array rather than a single energy selecting slit, we need as great a dispersion as possible. Therefore, we would like to follow our spectrometer by a magnifying lens. Consequently, the line along which electrons of varying energy are dispersed must be normal to the direction of the central ray at the spectrometer exit.

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EXELFS Studies of Carbon Fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133953 ◽

1990 ◽

Vol 48 (2) ◽

pp. 72-73

Author(s):

V. Serin ◽

K. Hssein ◽

G. Zanchi ◽

J. Sévely

Keyword(s):

Carbon Fibers ◽

Energy Analysis ◽

Electron Excitation ◽

Complex Structures ◽

High Modulus ◽

Promising Technique ◽

X Ray ◽

Fine Structures ◽

X Ray Absorption

The present developments of electron energy analysis in the microscopes by E.E.L.S. allow an accurate recording of the spectra and of their different complex structures associated with the inner shell electron excitation by the incident electrons (1). Among these structures, the Extended Energy Loss Fine Structures (EXELFS) are of particular interest. They are equivalent to the well known EXAFS oscillations in X-ray absorption spectroscopy. Due to the EELS characteristic, the Fourier analysis of EXELFS oscillations appears as a promising technique for the characterization of composite materials, the major constituents of which are low Z elements. Using EXELFS, we have developed a microstructural study of carbon fibers. This analysis concerns the carbon K edge, which appears in the spectra at 285 eV. The purpose of the paper is to compare the local short range order, determined by this way in the case of Courtauld HTS and P100 ex-polyacrylonitrile carbon fibers, which are high tensile strength (HTS) and high modulus (HM) fibers respectively.

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A Fault Detection Approach Based on Sound Signal Analysis for Equipment Monitoring

International Journal of Scientific Research in Science Engineering and Technology ◽

10.32628/ijsrset207430 ◽

2020 ◽

pp. 129-139

Author(s):

Weihai Sun ◽

Lemei Han

Keyword(s):

Fault Detection ◽

Signal Analysis ◽

Energy Analysis ◽

Detection Method ◽

Sound Signal ◽

Practical Significance ◽

Time Frequency ◽

Detection Approach ◽

Machine Fault ◽

Learning Data

Machine fault detection has great practical significance. Compared with the detection method that requires external sensors, the detection of machine fault by sound signal does not need to destroy its structure. The current popular audio-based fault detection often needs a lot of learning data and complex learning process, and needs the support of known fault database. The fault detection method based on audio proposed in this paper only needs to ensure that the machine works normally in the first second. Through the correlation coefficient calculation, energy analysis, EMD and other methods to carry out time-frequency analysis of the subsequent collected sound signals, we can detect whether the machine has fault.

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Experimental and Statistical Energy Analysis of the Structure-borne Noise in a Helicopter Cabin

International Review of Aerospace Engineering (IREASE) ◽

10.15866/irease.v10i6.13120 ◽

2017 ◽

Vol 10 (6) ◽

pp. 323

Author(s):

Raffaella Di Sante ◽

Marcello Vanali ◽

Elisabetta Manconi ◽

Alessandro Perazzolo

Keyword(s):

Energy Analysis ◽

Statistical Energy Analysis

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Energy analysis of propulsion systems for high speed vehicles

10.2514/6.1989-182 ◽

1989 ◽

Cited By ~ 2

Author(s):

PAUL CZYSZ ◽

S. MURTHY

Keyword(s):

High Speed ◽

Energy Analysis ◽

Propulsion Systems

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Theoretical investigation of Ramachandran plot of N-formyl-L-alanine-amide

10.31221/osf.io/8gbdp ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Genetic Algorithm ◽

Theoretical Investigation ◽

Energy Analysis ◽

Empirical Method ◽

Conformational Space ◽

Ramachandran Plot ◽

Global Minima ◽

Reasonable Time ◽

Semi Empirical

The full conformational space of N-formyl-L-alanine-amide was explored by the semi-empirical method AM1 coupled to the Multi Niche Crowding (MNC) genetic algorithm implemented in a package of programs developed in our laboratory. The structural and energy analysis of the resulting conformational space E(,ψ) exhibits 5 regions or minima ɣL, ɣD, ɛL, D and αD. The technique provides better detection of local and global minima within a reasonable time.

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