scholarly journals Image segmentation and its quantitative evaluation of X-ray CT data of geomaterials using EM algorithm

2014 ◽  
Vol 9 (4) ◽  
pp. 555-567 ◽  
Author(s):  
Toshifumi MUKUNOKI ◽  
Toshio FUJIMI ◽  
Hidetoshi MATSUMOTO
2010 ◽  
pp. 110220121911010
Author(s):  
KATSUHIKO KIMURA ◽  
Yasumasa Fukase ◽  
Michiko Makino ◽  
Chihiro Masaki ◽  
Tetsuji Nakamoto ◽  
...  

Sensors ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 238
Author(s):  
Jakub Šalplachta ◽  
Tomáš Zikmund ◽  
Marek Zemek ◽  
Adam Břínek ◽  
Yoshihiro Takeda ◽  
...  

In this article, we introduce a new ring artifacts reduction procedure that combines several ideas from existing methods into one complex and robust approach with a goal to overcome their individual weaknesses and limitations. The procedure differentiates two types of ring artifacts according to their cause and character in computed tomography (CT) data. Each type is then addressed separately in the sinogram domain. The novel iterative schemes based on relative total variations (RTV) were integrated to detect the artifacts. The correction process uses the image inpainting, and the intensity deviations smoothing method. The procedure was implemented in scope of lab-based X-ray nano CT with detection systems based on charge-coupled device (CCD) and scientific complementary metal–oxide–semiconductor (sCMOS) technologies. The procedure was then further tested and optimized on the simulated data and the real CT data of selected samples with different compositions. The performance of the procedure was quantitatively evaluated in terms of the artifacts’ detection accuracy, the comparison with existing methods, and the ability to preserve spatial resolution. The results show a high efficiency of ring removal and the preservation of the original sample’s structure.


Author(s):  
Ran Zhao ◽  
Hong Cai ◽  
Hua Tian ◽  
Ke Zhang

Abstract Purpose The application of the anatomical parameters of the contralateral hip joint to guide the preoperative template of the affected side relies on the bilateral hip symmetry. We investigated the bilateral hip symmetry and range of anatomical variations by measurement and comparison of bilateral hip anatomical parameters. Methods This study included 224 patients (448 hips) who were diagnosed with osteoarthritis (OA) and avascular necrosis (AVN) of the femur head, and underwent bilateral primary total hip arthroplasty (THA) in our hospital from January 2012 to August 2020. Imaging data included 224 patients X-ray and 30 CT data at the end of the cohort. Anatomical parameters, including the acetabular abduction angle and trochanteric height, were measured using the Noble method. Postoperative measurements included stem size, difference of leg length and offset. Results Except for the isthmus width, there were no significant differences in the anatomical morphology of the hip joint. Among the demographic factors, there was a correlation between body weight and NSA. Among various anatomical parameters, a correlation was present between medullary cavity widths of T + 20, T, and T − 20. The difference in the use of stem size is not due to the morphological difference of bilateral medullary cavity, but due to the different of 1- or 2-stage surgery. Conclusion Bilateral symmetry was present among the patients with normal morphology of the hip medullary cavity, theoretically confirming the feasibility of structural reconstruction of the hip joint using the hip joint on the uninjured side. Additionally, the difference in the morphology of the hip medullary cavity is not present in a single plane but is synergistically affected by multiple adjacent planes.


2002 ◽  
Vol 09 (02) ◽  
pp. 877-881 ◽  
Author(s):  
S. IMADA ◽  
S. SUGA ◽  
W. KUCH ◽  
J. KIRSCHNER

The benefits of combining soft X-ray magnetic circular dichroism and photoelectron microscopy are demonstrated by applying this combination (XMCD–PEEM) not only to magnetic domain imaging but also to quantitative evaluation of the distribution of spin and orbital magnetic moments. The latter takes full advantage of the spectroscopic aspect of XMCD–PEEM.


2011 ◽  
Vol 56 (4) ◽  
pp. 1031-1043 ◽  
Author(s):  
M J van der Bom ◽  
J P W Pluim ◽  
M J Gounis ◽  
E B van de Kraats ◽  
S M Sprinkhuizen ◽  
...  
Keyword(s):  
3D Mri ◽  
X Ray ◽  

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