Mammography image restoration based on a radiographic scattering model from a single projection: Experimental study

2017 ◽  
Vol 70 (6) ◽  
pp. 640-646
Author(s):  
Kyuseok Kim ◽  
Soyoung Park ◽  
Guna Kim ◽  
Hyosung Cho ◽  
Uikyu Je ◽  
...  
2021 ◽  
Author(s):  
Haoyang Li ◽  
Sining Li ◽  
Peng Jiang ◽  
Jianfeng Sun ◽  
Shihang Guo ◽  
...  

2002 ◽  
Vol 79 (4) ◽  
pp. 905-926 ◽  
Author(s):  
Sameer Deshpande ◽  
Jacqueline C. Hitchon

This experimental study tested Cause-Related Marketing (CRM) ads in the context of Benoit's Image Restoration Theory. The effects of three kinds of ads on the image of a brand and a nonprofit organization (NPO) after the release of an unfavorable news story were compared: brand ads, PSAs, and CRM ads. CRM ads produced more favorable responses than brand ads prior to scandal, but lost their advantage in the light of negative news.


2020 ◽  
Vol 166 ◽  
pp. 107257 ◽  
Author(s):  
Chenggang Dai ◽  
Mingxing Lin ◽  
Xiaojian Wu ◽  
Dong Zhang

Author(s):  
W.A. Carrington ◽  
F.S. Fay ◽  
K.E. Fogarty ◽  
L. Lifshitz

Advances in digital imaging microscopy and in the synthesis of fluorescent dyes allow the determination of 3D distribution of specific proteins, ions, GNA or DNA in single living cells. Effective use of this technology requires a combination of optical and computer hardware and software for image restoration, feature extraction and computer graphics.The digital imaging microscope consists of a conventional epifluorescence microscope with computer controlled focus, excitation and emission wavelength and duration of excitation. Images are recorded with a cooled (-80°C) CCD. 3D images are obtained as a series of optical sections at .25 - .5 μm intervals.A conventional microscope has substantial blurring along its optical axis. Out of focus contributions to a single optical section cause low contrast and flare; details are poorly resolved along the optical axis. We have developed new computer algorithms for reversing these distortions. These image restoration techniques and scanning confocal microscopes yield significantly better images; the results from the two are comparable.


Author(s):  
Norio Baba ◽  
Norihiko Ichise ◽  
Syunya Watanabe

The tilted beam illumination method is used to improve the resolution comparing with the axial illumination mode. Using this advantage, a restoration method of several tilted beam images covering the full azimuthal range was proposed by Saxton, and experimentally examined. To make this technique more reliable it seems that some practical problems still remain. In this report the restoration was attempted and the problems were considered. In our study, four problems were pointed out for the experiment of the restoration. (1) Accurate beam tilt adjustment to fit the incident beam to the coma-free axis for the symmetrical beam tilting over the full azimuthal range. (2) Accurate measurements of the optical parameters which are necessary to design the restoration filter. Even if the spherical aberration coefficient Cs is known with accuracy and the axial astigmatism is sufficiently compensated, at least the defocus value must be measured. (3) Accurate alignment of the tilt-azimuth series images.


Author(s):  
Richard B. Mott ◽  
John J. Friel ◽  
Charles G. Waldman

X-rays are emitted from a relatively large volume in bulk samples, limiting the smallest features which are visible in X-ray maps. Beam spreading also hampers attempts to make geometric measurements of features based on their boundaries in X-ray maps. This has prompted recent interest in using low voltages, and consequently mapping L or M lines, in order to minimize the blurring of the maps.An alternative strategy draws on the extensive work in image restoration (deblurring) developed in space science and astronomy since the 1960s. A recent example is the restoration of images from the Hubble Space Telescope prior to its new optics. Extensive literature exists on the theory of image restoration. The simplest case and its correspondence with X-ray mapping parameters is shown in Figures 1 and 2.Using pixels much smaller than the X-ray volume, a small object of differing composition from the matrix generates a broad, low response. This shape corresponds to the point spread function (PSF). The observed X-ray map can be modeled as an “ideal” map, with an X-ray volume of zero, convolved with the PSF. Figure 2a shows the 1-dimensional case of a line profile across a thin layer. Figure 2b shows an idealized noise-free profile which is then convolved with the PSF to give the blurred profile of Figure 2c.


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