scholarly journals The X-Ray Transform Projection of 3D Mother Wavelet Function

2013 ◽  
Vol 2013 ◽  
pp. 1-9
Author(s):  
Xiangyu Yang ◽  
Jiqiang Guo ◽  
Li Lu ◽  
Li Zeng
Keyword(s):  
Wavelet Transform ◽  
Three Dimensional ◽  
Computation Time ◽  
Projection Data ◽  
3D Image ◽  
Mother Wavelet ◽  
X Ray ◽  
Ray Transform ◽  
3D Wavelet Transform ◽  
Ray Projection

As we all know, any practical computed tomography (CT) projection data more or less contains noises. Hence, it will be inconvenient for the postprocessing of a reconstructed 3D image even when the noise in the projection data is white. The reason is that the noise in the reconstructed image may be nonwhite. X-ray transform can be applied to the three dimensional (3D) CT, depicting the relationship between material density and ray projection. In this paper, nontensor product relationship between the two dimensional (2D) mother wavelet and 3D mother wavelet is obtained by taking X-ray transform projection of 3D mother wavelet. We proved that the projection of the 3D mother wavelet is a 2D mother wavelet if the 3D mother wavelet satisfies certain conditions. So, the 3D wavelet transform of a 3D image can be implemented by the 2D wavelet transform of its X-ray transform projection and it will contribute to the reduction complexity and computation time during image processing. What is more, it can also avoid noise transfer and amplification during the processing of CT image reconstruction.

scholarly journals Convolutional Neural Network (CNN) Based Three Dimensional Tumor Localization Using Single X-Ray Projection

IEEE Access ◽  
2019 ◽  
Vol 7 ◽  
pp. 37026-37038 ◽  
Author(s):  
Ran Wei ◽  
Fugen Zhou ◽  
Bo Liu ◽  
Xiangzhi Bai ◽  
Dongshan Fu ◽  
...  
Keyword(s):  
Neural Network ◽  
Convolutional Neural Network ◽  
Three Dimensional ◽  
Tumor Localization ◽  
X Ray ◽  
Ray Projection

Three-dimensional tomography using a soft X-ray holographic microscope and CCD camera

1998 ◽  
Vol 5 (3) ◽  
pp. 1088-1089 ◽  
Author(s):  
Norio Watanabe ◽  
Sadao Aoki
Keyword(s):  
Tungsten Wire ◽  
Three Dimensional ◽  
Numerical Aperture ◽  
Ccd Camera ◽  
Depth Resolution ◽  
Projection Data ◽  
Back Projection ◽  
X Ray ◽  
Dimensional Reconstruction ◽  
Transverse Resolution

The depth resolution of a soft X-ray hologram is much worse than its transverse resolution because a single soft X-ray hologram has a small numerical aperture. To obtain a three-dimensional image, in-line holograms of a specimen were recorded from various directions and reconstructed to obtain two-dimensional projection data. Then, a three-dimensional reconstruction was performed by back-projection of these reconstructed holograms. Three-dimensional images of a tungsten wire of diameter 10 µm and a fossil of a diatom were obtained.

scholarly journals Microstructural characterization of a Canadian oil sand

2012 ◽  
Vol 49 (10) ◽  
pp. 1212-1220 ◽  
Author(s):  
Dinh Hong Doan ◽  
Pierre Delage ◽  
Jean François Nauroy ◽  
Anh Minh Tang ◽  
Souhail Youssef
Keyword(s):  
Three Dimensional ◽  
Microstructural Characterization ◽  
Water Layer ◽  
3D Image ◽  
Oil Sand ◽  
X Ray ◽  
Mcmurray Formation ◽  
Gas Expansion

The microstructure of oil sand samples extracted at a depth of 75 m from the estuarine Middle McMurray Formation (Alberta, Canada) has been investigated using high resolution three-dimensional (3D) X-ray microtomography (µCT) and cryo scanning electron microscopy (CryoSEM). µCT images evidenced some dense areas composed of highly angular grains surrounded by fluids, which are separated by larger pores full of gas. In dense areas, 3D image analysis provided porosity values comparable with in situ log data and macroscopic laboratory determinations, showing that they are representative of intact states. µCT hence provided some information on the morphology of the cracks and disturbance created by gas expansion. The CryoSEM technique, in which the sample is freeze fractured within the SEM chamber prior to observation, provided pictures in which the (frozen) bitumen clearly appears between the sand grains. No evidence of the existence of a thin connate water layer between grains and the bitumen, frequently mentioned in the literature, has been obtained. Bitumen appears to strongly adhere to the grains, with some grains being completely coated. The curved shape of some bitumen menisci suggests a bitumen wet behaviour.

Towards sub-100-nm X-ray microscopy for tomographic applications

2010 ◽  
Vol 25 (2) ◽  
pp. 157-160 ◽  
Author(s):  
P. Bruyndonckx ◽  
A. Sasov ◽  
B. Pauwels
Keyword(s):  
Response Curve ◽  
Three Dimensional ◽  
Specimen Size ◽  
Tomographic Imaging ◽  
Detector Response ◽  
Simulation Studies ◽  
Depth Of Focus ◽  
X Ray ◽  
Projection Images ◽  
Ray Projection

We have demonstrated that structures down to 150 nm can be visualized in X-ray projection images using nanofocus X-ray sources. Due to their unlimited depth of focus, they do not possess a limit on the specimen size. This is essential for three-dimensional tomographic imaging of samples with a diameter larger than a few microns. Further simulation studies have shown that optimization of the detector response curve and switching from a reflective X-ray target to a transmission target should allow us to reach sub-100-nm resolutions.

Kidney Glomerulus Observation in Interactive VR Space

2003 ◽  
Vol 03 (04) ◽  
pp. 629-637
Author(s):  
Osamu Oshiro ◽  
Kumi Kamada ◽  
Masataka Imura ◽  
Kunihiro Chihara ◽  
Eiji Toyota ◽  
...  
Keyword(s):  
Three Dimensional ◽  
3D Image ◽  
Surface Rendering ◽  
Ccd Cameras ◽  
Projection System ◽  
X Ray ◽  
Kidney Glomerulus ◽  
On Line ◽  
Immersive Environment ◽  
Computer Tomogram

This paper presents the system designed to observe kidney glomeruli interactively with conventional CCD cameras and immersive virtual reality (VR) space. First, we captured the X-ray transmitted images and converted them to computer tomogram (CT). Second, the three-dimensional (3D) image was reconstructed using various image processing, binarization, dilation, contraction, labeling and surface rendering. Third, we presented the 3D image on the immersive projection system (IPS) and installed the function of on-line counting of the number of glomeruli. This system provides an observer the immersive environment and enables him to count the kidney glomeruli interactively.

3D Image-Based Modeling of Ductile Fracture in an Aluminum Alloy Using Synchrotron X-Ray CT Images

2007 ◽  
Vol 561-565 ◽  
pp. 263-266
Author(s):  
L. Qian ◽  
Hiroyuki Toda ◽  
Kentaro Uesugi ◽  
Masakazu Kobayashi ◽  
Toshiro Kobayashi
Keyword(s):  
Aluminum Alloy ◽  
Fracture Behavior ◽  
Computational Models ◽  
Three Dimensional ◽  
3D Image ◽  
3D Images ◽  
X Ray ◽  
Crack Geometry ◽  
Image Based Modeling ◽  
Insight Into

Traditional computational models always assume idealized crack geometry. However, actual crack geometry is very complex in real materials and thus, those simulations do not realistically represent the actual loading conditions of a real crack. In this paper, three-dimensional (3D) image-based simulation was performed to investigate the fracture behavior of an aluminum alloy, and the model takes into account the real crack geometry based on the 3D images of the crack. Accordingly, many essential features of fracture can be identified and interpreted, and some new insight into fracture behavior in real materials can be offered.

scholarly journals Computing segmentations directly from x-ray projection data via parametric deformable curves

2017 ◽  
Vol 29 (1) ◽  
pp. 014003
Author(s):  
Vedrana Andersen Dahl ◽  
Anders Bjorholm Dahl ◽  
Per Christian Hansen
Keyword(s):  
Projection Data ◽  
X Ray ◽  
Ray Projection

scholarly journals Iterative tomography of pipes during operation

2021 ◽  
Vol 66 (4) ◽  
pp. 505-512
Author(s):  
S. A. Zolotarev ◽  
V. L. Vengrinovich ◽  
S. I. Smagin
Keyword(s):  
Wall Thickness ◽  
Pipe Wall ◽  
Three Dimensional ◽  
Projection Data ◽  
Beam Hardening ◽  
Pipe Wall Thickness ◽  
X Ray ◽  
Angle Of View ◽  
Imaging Plates ◽  
Made In

The pipe wall thickness was estimated based on three-dimensional images of the pipe recovered from several X-ray projections, which were made in a limited angle of view. Since the effects of scattered radiation and beam hardening are up to 50 % of the main radiation, ignoring them leads to blur of the image and inaccuracy in determining dimensions. To restore pipe images from projections, a volume and/or shell representation of the pipe is used, as well as iterative Bayesian methods. Using these methods, the error in estimating the pipe wall thickness from the projection data can be equal to or less than 300 μm. It has been shown that standard X-ray projections on the film or imaging plates used to obtain data can be used to restore pipe wall thickness profiles in factory conditions.

scholarly journals Automatic 3D image registration for nano-resolution chemical mapping using synchrotron spectro-tomography

2021 ◽  
Vol 28 (1) ◽  
pp. 278-282
Author(s):  
Jin Zhang ◽  
Jun Hu ◽  
Zhisen Jiang ◽  
Kai Zhang ◽  
Peng Liu ◽  
...  
Keyword(s):  
Image Registration ◽  
Energy Levels ◽  
Three Dimensional ◽  
Intensity Variation ◽  
Chemical Mapping ◽  
3D Image ◽  
Experimental Conditions ◽  
Registration Method ◽  
X Ray ◽  
3D Image Registration

Nano-resolution synchrotron X-ray spectro-tomography has been demonstrated as a powerful tool for probing the three-dimensional (3D) structural and chemical heterogeneity of a sample. By reconstructing a number of tomographic data sets recorded at different X-ray energy levels, the energy-dependent intensity variation in every given voxel fingerprints the corresponding local chemistry. The resolution and accuracy of this method, however, could be jeopardized by non-ideal experimental conditions, e.g. instability in the hardware system and/or in the sample itself. Herein is presented one such case, in which unanticipated sample deformation severely degrades the data quality. To address this issue, an automatic 3D image registration method is implemented to evaluate and correct this effect. The method allows the redox heterogeneity in partially delithiated Li x Ta0.3Mn0.4O2 battery cathode particles to be revealed with significantly improved fidelity.

Three-dimensional X-ray imaging system and its application in power equipment

2019 ◽  
Vol 61 (10) ◽  
pp. 572-576
Author(s):  
Fei Zhong ◽  
Fumu Zhang ◽  
Liping Zhang ◽  
Ming Hao
Keyword(s):  
Power Supply ◽  
Imaging System ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Projection Data ◽  
Power Equipment ◽  
Control Data ◽  
X Ray ◽  
Inverse Transform ◽  
X Ray Imaging

The medical computed tomography (CT) technique cannot be directly applied to power equipment, such as gas-insulated switchgear (GIS), because of its huge size and immovability. In this research, a three-dimensional X-ray imaging system is developed for GIS equipment. The three-dimensional X-ray imaging system includes machinery, motion control, data acquisition, image reconstruction and three-dimensional image display subsystems. The principle of three-dimensional X-ray imaging is based on the Radon transform and the inverse transform. The rotary scanning device successfully collects 360 sets of projection data. The tomographic image is reconstructed using the acquired projection data. Shown in this paper is what is believed to be the world's first three-dimensional structure photograph of GIS that can be sliced and displayed using X-ray imaging. The application of the three-dimensional X-ray imaging system to the 110 kV GIS equipment at the Shayao Station of the Dongguan Power Supply Bureau shows that the overall accuracy of the system can reach up to 200 microns and the highest resolution of the output tomogram can reach up to 3160 × 3160 pixels.

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