Kyushu University Academic Staff Educational and Research Activities Database
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Shizuo Kaji Last modified date:2021.04.29



Graduate School
Undergraduate School


Homepage
https://kyushu-u.pure.elsevier.com/en/persons/shizuo-kaji
 Reseacher Profiling Tool Kyushu University Pure
https://www.skaji.org/
https://github.com/shizuo-kaji/
Academic Degree
Doctor of Science
Country of degree conferring institution (Overseas)
No
Field of Specialization
topology
ORCID(Open Researcher and Contributor ID)
0000-0002-7856-6536
Total Priod of education and research career in the foreign country
02years00months
Outline Activities
My research interests are primarily in the areas of algebraic topology. More specifically, I study spaces with group actions, which exhibit a rich connection to algebraic/combinatorial objects such as graphs and polynomials. I am interested in this correspondence between topology and algebra/combinatorics, and I study topological problems through algebro-combinatorial techniques and vice versa. I am also working on applications of topology to various fields such as computer graphics.
Research
Research Interests
  • My research interests are primarily in the areas of algebraic topology. More specifically, I study spaces with group actions, which exhibit a rich connection to algebraic/combinatorial objects such as graphs and polynomials. I am interested in this correspondence between topology and algebra/combinatorics, and I study topological problems through algebro-combinatorial techniques and vice versa. I am also working on applications of topology to various fields such as computer graphics and data analysis.
    keyword : topology, industrial maths, shape processing, data analysis
    2008.04~2029.01.
Academic Activities
Reports
1. , [URL].
Papers
1. Satoshi Kida, Shizuo Kaji, Kanabu Nawa, Toshikazu Imae, Takahiro Nakamoto, Sho Ozaki, Takeshi Ohta, Yuki Nozawa, Keiichi Nakagawa, Visual enhancement of Cone-beam CT by use of CycleGAN, Medical physics, 10.1002/mp.13963, 47, 3, 998-1010, 2020.03, Purpose: Cone-beam computed tomography (CBCT) offers advantages over conventional fan-beam CT in that it requires a shorter time and less exposure to obtain images. However, CBCT images suffer from low soft-tissue contrast, noise, and artifacts compared to conventional fan-beam CT images. Therefore, it is essential to improve the image quality of CBCT. Methods: In this paper, we propose a synthetic approach to translate CBCT images with deep neural networks. Our method requires only unpaired and unaligned CBCT images and planning fan-beam CT (PlanCT) images for training. The CBCT images and PlanCT images may be obtained from other patients as long as they are acquired with the same scanner settings. Once trained, three-dimensionally reconstructed CBCT images can be directly translated into high-quality PlanCT-like images. Results: We demonstrate the effectiveness of our method with images obtained from 20 prostate patients, and provide a statistical and visual comparison. The image quality of the translated images shows substantial improvement in voxel values, spatial uniformity, and artifact suppression compared to those of the original CBCT. The anatomical structures of the original CBCT images were also well preserved in the translated images. Conclusions: Our method produces visually PlanCT-like images from CBCT images while preserving anatomical structures..
2. Soojin Cho, Suyoung Choi, Shizuo Kaji, Geometric representations of finite groups on real toric spaces, Journal of the Korean Mathematical Society, 10.4134/JKMS.j180646, 56, 5, 1265-1283, 2019.01, We develop a framework to construct geometric representations of finite groups G through the correspondence between real toric spaces X<sup>R</sup> and simplicial complexes with characteristic matrices. We give a combinatorial description of the G-module structure of the homology of X<sup>R</sup>. As applications, we make explicit computations of the Weyl group representations on the homology of real toric varieties associated to the Weyl chambers of type A and B, which show an interesting connection to the topology of posets. We also realize a certain kind of Foulkes representation geometrically as the homology of real toric varieties..
Works, Software and Database
1.
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