METHOD OF COMPUTER CONTROL OF TWISTED THREAD PARAMETERS FROM ITS IMAGE

A non-hardware method for computer control of the geometric parameters of a twisted thread using a two-dimensional Fourier transform program of its computer image is proposed. First, the program calculates the diffraction pattern from the investigated image of the thread. Then, the same program builds a diffraction pattern from the image of the first pattern, which does not contain speckles in the proposed method. This makes it possible to carry out its automatic computer analysis with the output to the digital values of the calculated parameters. The effectiveness of the method is illustrated on model and industrial samples of synthetic threads.

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Studies on Automatic Recognition System of Fabric Weaves’ Parameters

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.341-342.829 ◽

2011 ◽

Vol 341-342 ◽

pp. 829-832 ◽

Cited By ~ 1

Author(s):

Yan Mei Li ◽

Xiao Kun Qiu ◽

Zhen Zhen Jiang

Keyword(s):

Fourier Transform ◽

Power Spectrum ◽

Computer Image ◽

Recognition System ◽

Automatic Recognition ◽

Image Process ◽

Two Dimensional ◽

Process Technology ◽

Weave Pattern ◽

In Virtue Of

In virtue of having some periodicity in space, the fabric weave pattern can be recognized by using computer image process technology. Firstly, the reflected image and transmissive image of fabric were scanned and disposed. Then its image of two-dimensional power spectrum and image of autocorrelation were obtained by means of Fourier transform technology. Finally the fabric weave parameters can be calculated, including density of warp and weft, the size of warp and weft and the yarn numbers of weave repetition etc. Based on foregoing theory, this paper develops automatic recognition system of fabric weave parameters, which is worth of popularizing.

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Comparison of Calculated and Recorded Electron Energy-Loss Spectra of Aluminium and Carbon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133916 ◽

1990 ◽

Vol 48 (2) ◽

pp. 64-65

Author(s):

L. Reimer ◽

R. Oelgeklaus

Keyword(s):

Fourier Transform ◽

Energy Loss ◽

Electron Energy ◽

Rotational Symmetry ◽

Mean Free Path ◽

Single Scattering ◽

Specimen Thickness ◽

Two Dimensional ◽

Image Position ◽

Electron Energy Loss

Quantitative electron energy-loss spectroscopy (EELS) needs a correction for the limited collection aperture α and a deconvolution of recorded spectra for eliminating the influence of multiple inelastic scattering. Reversely, it is of interest to calculate the influence of multiple scattering on EELS. The distribution f(w,θ,z) of scattered electrons as a function of energy loss w, scattering angle θ and reduced specimen thickness z=t/Λ (Λ=total mean-free-path) can either be recorded by angular-resolved EELS or calculated by a convolution of a normalized single-scattering function ϕ(w,θ). For rotational symmetry in angle (amorphous or polycrystalline specimens) this can be realised by the following sequence of operations :(1)where the two-dimensional distribution in angle is reduced to a one-dimensional function by a projection P, T is a two-dimensional Fourier transform in angle θ and energy loss w and the exponent -1 indicates a deprojection and inverse Fourier transform, respectively.

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