Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Reiji Tsuruno Last modified date:2022.06.22

Professor / Interaction Design / Department of Media Design / Faculty of Design

1. Doi Kohei, Morimoto Yuki, Tsuruno Reiji, Global Illumination-Aware Stylised Shading, COMPUTER GRAPHICS FORUM, 10.1111/cgf.14397, 40, 7, 11-20, 2021.10, Our aim is to convert an object's appearance to an arbitrary colour considering the light scattering in the entire scene, which is often called the global illumination. Existing stylisation methods convert the colour of an object with a 1-dimensional texture for 3-dimensional computer graphics to reproduce a typical style used in illustrations and cel animations. However, they cannot express global illumination effects. We propose two individual methods to compute the global illumination and convert the shading to an arbitrary colour. The methods reproduce reflections in other objects with the converted colour. As a result, we can convert the colour of illumination effects that have not yet been reproduced, such as soft shadows and refractions..
2. Line Drawing Colorization of Character Illustration by Color Reference Image for Accurate Eye Colors based on Deep Learning.
3. Kenta Akita, Yuki Morimoto, Reiji Tsuruno, Colorization of Line Drawings with Empty Pupils, COMPUTER GRAPHICS FORUM, 10.1111/cgf.14171, 39, 7, 601-610, 2020.10.
4. Kenta Akita, Yuki Morimoto, Reiji Tsuruno, Deep-Eyes: Fully Automatic Anime Character Colorization with Painting of Details on Empty Pupils, Eurographics, accepted in EUROGRAPHICS & EUROVIS 2020 short paper, 2020.06, Many studies have recently applied deep learning to the automatic colorization of line drawings. However, it is difficult to paint empty pupils using existing methods because the networks are trained with pupils that have edges, which are generated from color images using image processing. Most actual line drawings have empty pupils that artists must paint in. In this paper, we propose a novel network model that transfers the pupil details in a reference color image to input line drawings with empty pupils. We also propose a method for accurately and automatically coloring eyes. In this method, eye patches are extracted from a reference color image and automatically added to an input line drawing as color hints using our eye position estimation network..
5. Kenta Akita, Yuki Morimoto, Reiji Tsuruno, Fully automatic colorization for anime character considering accurate eye colors, SIGGRAPH2019, 10.1145/3306214.3338585, Article No:11, 1-2, SIGGRAPH2019,ACM Annual conference
ISBN (Electronic) 9781450363143
Published - Jul 28 2019, 2019.07, In this paper, we propose a method to colorize line drawings of anime characters' faces with colors from a reference image. Previous studies using reference images often fail to realize fully-automatic colorization, especially for small areas, e.g., eye colors in the resulting image may differ from the reference image. The proposed method accurately colorizes eyes in the input line drawing using automatically computed hints. The hints are round patches used to specify the positions and corresponding colors extracted from the eye areas of a reference image..
6. Tomoko Nakamoto, Philip Sköld, Reiji Tsuruno., Eye Movement Model for Face-to-Face Interaction of Virtual Characters, Asia Digital Art and Design, 4C-3, 2018.11.
7. Generating Latte Art Style Flow Pattern.
8. taihei meno, Reiji Tsuruno, Local Density Calibration for Position Based Fluids, International Journal of Asia Digital Art and Design, 21, 1, 41-48, 2017.10, This paper propose a improved PBF(position based fluid model)-based method for simulating realistic incompressible fluid flow. Our goal is to present simulation method of fluid phenomena as realistic as possible in realtime to many applications that require a high frame rate. Rapid fluid simulations are important for realizing real-time applications in computer graphics. Position based fluids (PBF) has been suggested as a practical method for real-time simulations of incompressible fluids. This method is based on the SPH(smoothed particle hydrodynamics) and realizes incompressibility by restricting the density. Furthermore, it reduces the calculation costs by allowing large time steps. However, because it iteratively calculates the density constraints, PBF is impractical for applications requiring high resolution and high frame rate. To increase the simulation speed of PBF, we replace the iterative density calculation by a density model. In the conventional method, iterating few density calculations compresses the simulated fluid. To resolve this problem, we consider the particle density and the direction of the fluid flow. We develop a computational model based on this hypothesis and verify its usefulness in simulations. The method suppresses the fluid compression even in a non-iterative model. We conclude that the proposed computational model effectively maintains a constant density in PBF..
9. Taihei Meno, Reiji Tsuruno, Local Pressure Correction Model for Position Based Fluids, Asia Digital Art and Design, 4A-6, 2016.11, Speed of fluid simulation calculations is an important factor for realizing real-time applications in computer graphics.
Position based fluids (PBF), which is an incompressible fluid simulation method, has been suggested as a practical
method for real-time simulation. Using this method, it is possible to take large time steps; therefore, the cost of
calculation can be reduced. However, method is not practical for applications that require high resolution and frame rate
because it is necessary to iteratively calculate the density constraints. In this study, we developed a pressure model that
replaces the iterative density calculation in PBF to realize faster simulation. First, we hypothesized that problems with
incompressibility caused by a small number of iterations can be solved by considering the influence of pressure. Second,
we used an alternative pressure model that uses this hypothesis and verified it using simulation. The pressure
interpolation model uses the function relating to the distance and the density. The results confirm that compression of the
fluid can be suppressed even with a small number of iterations. Finally, by considering the influence of pressure in PBF, it
was possible to substitute the proposed model for iterative calculation of the density constraints..
10. Maki Kitamura, Reiji Tsuruno, 2.5D Modeling from Illustrations of Different Views, international Journal of Asia Digital Art and Design, 8, 4, 74-79, 2015.01, When artists design characters, they draw illustrations viewed from the front, side or slant views. In this paper, we create a 2.5D model using such illustrations. A 2.5D model is a model that is created by arranging deformable billboards along the depth direction, and it can express appearance of the character between two viewpoints with considering depth information.
Our method uses two cartoon-like illustrations and the corresponding eye directions as inputs. These illustrations are composed of contours and closed regions painted with uniform colors. Given closed regions in illustrations, our method finds corresponding closed regions between two illustrations based on an improved similarity function, which yields better matching than a previous method. After obtaining correspondences of closed regions, our method creates a 2.5D model by transforming each pair of matched regions as a 3D billboard whose position can be estimated based on the correspondence. These processes are semi-automatic. The user then assigns feature points manually along the corresponding contours of matched regions so that the contours can be interpolated naturally. Finally, by completing regions that appear or vanish with user strokes, our method can interpolate illustrations with occluded regions. We demonstrate that our method can create 2.5D models with various illustrations..
11. Jun Yoshino, Reiji Tsuruno, Interactive fluid control by shape matching, 芸術科学会, 13, 3, 169-176, 2014.09, [URL], In this paper, we propose an interactive method to control fluid behavior by using a target shape. To achieve the desired motion, we define additional forces using control particles that employ the Navier–Stokes quation. Control particles are generated from a fluid area chosen by the user, and their behavior is sequentially determined using a shape-matching method referring to the target shape. Our method enables interactive simulation of fluid animation that is gradually deformed to the target shape following physical laws..
12. Junmin Park, Reiji Tsuruno, A Color Palette based Interface for Biological Iridescences Rendering, Asia Digital Art and Design Association, 18, 1, 4-11, 2014.07, [URL], Iridescent colors can be observed on many biological objects including morpho butterflies and Japanese jewel beetles. While ordinary colors are induced by pigments in surface, the iridescent colors are caused by interference of light due to microstructure covering the objects. To render iridescences in computer graphics, users need to consider a lot of physical parameters such as index of refraction or film layer thickness. However, in such input systems, users are difficult to predict rendering results since iridescence is affected by combination of those many physical factors. In this paper, we propose a color palette based interface for biological iridescences rendering, with which users can pass information for rendering iri-descences to system by picking colors instead of by inputting physical data of surface. Incident angle dependency of re-flectance spectrum is studied to achieve physically sound simulation and color picking user interface. We also evaluated our system through rendering results and user study in the latter half of this article..
13. Diffusion-Adsorption Theory-Based Visual Simulation Model for Dying Techniques.
14. Maki (Terai) Kitamura, Yoshihiro Kanamori, Jun Minani, Yukio Fukui, Reiji Tsuruno, Motion Frame Omission for Cartoon-like Effects, 2014 International Workshop on Advanced Image Technology, 148-152, Full Paper C2_P066.pdf, 2014.01.
15. Maki Terai, Reiji Tsuruno, An Interactive Tile-Based Modeling Interface, Nicograph International 2013, Nicograph International 2013, proceeding DVDROM, pp.10-13, 2013.06, This paper presents a novel modeling interface and method that uses two-dimensional (2D) data. In general, 2D computer graphics are most commonly used to depict 2D structures. However, many computer games often depict three-dimensional (3D) structures using 2D computer graphics. We dene such an expression as an overhead view. Although an overhead view has no 3D structure, we can perceive an ambiguous 3D structure from it. In this study, we dene shape perception rules from the overhead view and propose a novel modeling system using it. We also propose a tile-based interface as a prototype system that can create a 3D shape from an overhead view and can seamlessly convert an overhead view into a 3D view. In addition, we conduct a psychological experiment by means of which we conrmed our system is highly intuitive and can quickly create 3D models..
16. Jun Yoshino, Reiji Tsuruno, Interactive Shape Control for Fluid Animation, Nicograph International 2013, 108-114, Nicograph International proceeiings DVDROM, pp.108-114, 2013, 2013.06, In this paper, we propose an interactive method to control uid behavior by using a target shape. To achieve the desired motion, we dene the additional forces by using control particles employing the Navier-Stokes equation. Control particles are generated from a fuid area chosen by the user, and their behavior is sequentially determined by using a shape-matching method referring to the target shape. Our method enables one to interactively simulate uid animation, which is gradually deformed to the target shape following a physical law..
17. Ryoichi Ando, Nils Thurey, tsuruno reiji, Preserving Fluid Sheets with Adaptively Sampled Anisotropic Particles, IEEE Transactions on Visualization and Computer Graphics , IEEE,, 18, 8, 1202-1214, (IEEE computer Society Digital Library, 09 March 2012), 2012.08, [URL], This paper presents a particle-based model for preserving fluid sheets of animated liquids with an adaptively sampled Fluid-Implicit-Particle (FLIP) method. In our method, we preserve fluid sheets by filling the breaking sheets with particle splitting in the thin regions, and by collapsing them in the deep water. To identify the critically thin parts, we compute the anisotropy of the particle neighborhoods, and use this information as a resampling criterion to reconstruct thin liquid surfaces. Unlike previous approaches, our method does not suffer from diffusive surfaces or complex re-meshing operations, and robustly handles topology changes with the use of a meshless representation. We extend the underlying FLIP model with an anisotropic position correction to improve the particle spacing, and adaptive sampling to efficiently perform simulations of larger volumes. Due to the Lagrangian nature of our method, it can be easily implemented and efficiently parallelized. Our results show that our method can produce visually complex liquid animations with thin structures and vivid motions..
18. Ryoichi Ando, Reiji Tsuruno, A Particle-based Method for Preserving Fluid Sheets, SCA '11 Proceedings of the 2011 ACM SIGGRAPH/Eurographics Symposium on Computer Animation ACM New York, NY, USA ©2011 , 10.1145/2019406.2019408, Awarded (Honorable Mention)
, 2011.08, We present a new particle-based method that explicitly preserves thin fluid sheets for animating liquids. Our primary contribution is a meshless particle-based framework that splits at thin points and collapses at dense points to prevent the breakup of liquid. In contrast to existing surface tracking methods, the proposed framework does not suffer from numerical diffusion or tangles, and robustly handles topology changes by the meshless representation. As the underlying fluid model, we use Fluid-Implicit-Particle (FLIP) with weak spring forces to generate smooth particle-based liquid animation that maintains an even spatial particle distribution in the presence of eddying or inertial motions. The thin features are detected by examining stretches of distributions of neighboring particles by performing Principle Component Analysis (PCA), which is used to reconstruct thin surfaces with anisotropic kernels. Our algorithm is intuitively implemented, easy to parallelize and capable of producing visually complex thin liquid animations..
19. An Interactive Brush Stroke Synthesis Using Exemplar Images.
20. Ryoichi Ando, Reiji Tsuruno, Vector graphics depicting marbling flow, Computers & Graphics, Elsevier, , 35, 1, 148-159, Volume 35, Issue 1, February 2011, Pages 148-159
Extended Papers from Non-Photorealistic Animation and Rendering (NPAR) 2010 , 2011.02.
21. Ryoichi Ando, Reiji Tsuruno, “An Interactive Brush Stroke Synthesis Using Exemplar Images”, Journal of the Institute of Image Electronics Engineers of Japan, 10.11371/iieej.40.578, 40, 4, 578-586, 2011.01, This paper describes an interactive technique for generating brush strokes used in exemplar images. The proposed method decomposes several exemplar images of brush strokes into small fragments that are stitched together through one-dimensional texture synthesis in order to generate the final brush stroke silhouettes. In contrast to previous methods in which the strokes are generated by per-pixel computation or using physically based simulation, our method is not only less computationally expensive but also capable of simulating various kinds of brushes. In addition, we introduce a fluid-dynamics-driven post-process and a Kubelka-Munk synthesis method to make the paint strokes appear more real. Our evaluation experiments show that our method can handle various media such as oil paints, watercolors, charcoal, and pastels. We also obtained interesting results with lipsticks and fingers..
22. Ryoichi Ando, Reiji Tsuruno, High-frequency aware PIC/FLIP in liquid animation, ACM SIGGRAPH ASIA 2010 Sketches, SA'10 ACM SIGGRAPH ASIA 2010 Sketches, SA'10, 10.1145/1899950.1899975, 2010.12, We present a simple extension to PIC/FLIP(Particle-in-Cell/Fluid-Implicit- Particle) for animating liquid with enhanced behaviors such as pushing or eddying (Figure 1), which we call HFA/PIC/FLIP (High-frequency aware PIC/FLIP). As a fundamental approach we use PIC/FLIP [Brackbill and Ruppel 1986] and compute approximate low-frequency part and high-frequency part of particles velocities. Low-frequency velocities are entirely projected onto divergence free and high-frequency field is partially projected onto divergence free to achieve realistic liquid animations. In contrast to the PIC/FLIP proposed by Zhu and Bridson [Zhu and Bridson 2005]; our approach facilitates "pushing" or "curly" features whereas their approach disperses the momentum towards noisy directions, resulting in dispersion. Recently similar approach has been done with coarse to fine mesh grid [Lentine et al. 2010], we refined directly with particles. We produced several footage of liquid animation and compared with competitive alternatives to show the benefits of the proposed algorithm..
23. Semantic Affine Transformation.
24. Yasuyuki Tomita, Reiji Tsuruno, Motion texture animation of water surface, ACM SIGGRAPH 2010 Posters, SIGGRAPH '10 ACM SIGGRAPH 2010 Posters, SIGGRAPH '10, 10.1145/1836845.1836963, 2010.09, We present a new method for making wave animation from still water image. In our method, users can control the behavior of wave in the water surface intuitively and interactively. After we simulate the wave using a Spectral Method [Tessendorf 1999], we have the water surface corresponding to the projection system of static images. Previous works for animating water surface. Chuang et al [Chuang and Goldman 2005] proposed a method for generating an animating of picture using displacement mapping and warping, however, those methods are only effective for gentle and calm water surfaces. Contrarily, our method is adaptively used for large scale waves of water height field..
25. Ryoichi Ando, Reiji Tsuruno, Vector fluid
A vector graphics depiction of surface flow, 8th Meeting of the International Symposium on Non-Photorealistic Animation and Rendering, NPAR 2010 Proceedings of NPAR 2010 The 8th International Symposium on Non-Photorealistic Animation and Rendering, 10.1145/1809939.1809954, 129-135, 2010.07, We present a simple technique for creating fluid silhouettes described with vector graphics, which we call "Vector Fluid." In our system, a solid region in the fluid is represented as a closed contour and advected by fluid flow to form a curly and clear shape similar to marbling or sumi-nagashi (See Figure 1). The fundamental principle behind our method is that contours of solid regions should not collide. This means that if the initial shape of the region is a concave polygon, that shape should maintain its topology so that it can be rendered as a regular concave polygon, no matter how irregularly the contour is distorted by advection. In contrast to other techniques, our approach explicitly neglects topology changes to track surfaces in a trade off of computational cost and complexity. We also introduce an adaptive contour sampling technique to reduce this extra cost. We explore specific examples in 2D for art oriented usage and show applications and robustness of our method to exhibit organic fluid components. We also demonstrate how to port our entire algorithm onto a GPU to boost interactive performance for complex scenes..
26. Ryoichi Ando, Reiji Tsuruno, Vector Fluid - A Vector Graphics Depiction of Surface Flow, SBIM-NPAR 2010; The 2010 Joint Session of the Symposia on Sketch Based Interfaces and Modeling and Non-Photorealistic Animation and Rendering , 未定, Fullpaper, 2010.06.
27. Ryoichi Ando, Reiji Tsuruno, Segmental Brush Synthesis with Stroke Images, Eurographics 2010, 2010, short paper, 2010.05.
28. Ryoichi Ando, Reiji Tsuruno, Vector Fluid: A Vector Art Representation of Fluid, SIGGRAPH Asia 2009, 2010, DVD #2, Sketches&Posters, ISBN 978-1-60558-858-2, 2009.12.
29. Ryoichi Ando, Reiji Tsuruno, Vector fluid
A vector art representation of fluid, ACM SIGGRAPH ASIA 2009 Sketches, SIGGRAPH ASIA '09 ACM SIGGRAPH ASIA 2009 Sketches, SIGGRAPH ASIA '09, 10.1145/1667146.1667153, 2009.12, We present a new approach for rendering fluid with a style of vector graphics. The proposed method of vector art rendering of fluid exhibits a curly, beautiful and clear silhouette which deserves artistic expression. (See Figure 1) In computer vision, fluid has been mainly focused on capturing realistic behavior. Thanks to the much contribution of seminal works, large knowledge of photorealistic rendering of fluid have been amassed. On the other hand, although some approaches of the artistic rendering of fluid proposed [Selle et al. 2004; Eden et al. 2007], it seems that the area is not researched intensively and this kind of rendering technique still remains untouched. In order to achieve vector art rendering, we have to track the target region in fluid. However, popular methods of tracking interface model fluid with density field or collection of particles which introduce sudden topological changes and it is challenging to track them precisely. Instead, we consider the velocity field is infinitely continuous so that none of the part of fluid contour intersects each other at any state. Even though such consideration is questionable in physically derived model, this concept of non-intersection of contour leads a very simple algorithm and exhibits nice results. In this paper we first briefly describe the algorithm for vector fluid rendering and secondly we show some artworks created by our method to demonstrate the potential of our algorithm..
30. Taichi Nishiyori, Souei Sato, Narumi Tashiro, Toki Takeda, Ryouichi Ando, Maki Terai, Taketoshi Ushiama, Reiji Tsuruno, Fu-Fuu: Interactive Game using Breath Control, SIGGRAPH ASIA 2008, Full Conference DVD #1, /content/sketches/nishiyori.pdf, ISBN 978-1-60558-388-4/08/0012,
SIGGRAPH Asia 2008, Singapore, December 10-13, 2008, 2008.12.
31. Tetsuyuki Minamihara, Maki Terai, Reiji Tsuruno, Visual Simulation of Scattering and Settling of Fine Particles, SIGGRAPH ASIA 2008, Full Conference DVD #1, /content/sketches/minamihara.pdf, ISBN 978-1-60558-388-4/08/0012,
Siggraph Asia 2008, Singapore, December 10-13, 2008, 2008.12.
32. Yuki Morimoto, Masayuki Tanaka, Reiji Tsuruno, Kiyoshi Tomimatsu, Visualization of Dyeing based on Diffusion and Adsorption Theories, PacificGraphics2007, IEEE computer society, proceedings of 15th Pacific conference on Computer Graphics and Applications(PacificGraphics2007), pp.57-64, published by the IEEE Computer Society, 2007.10.
33. Yuki Morimoto, Masayuki Tanaka, Reiji Tsuruno, Kiyoshi Tomimatsu, Liquid Diffusion Model that Accounts for Variety of Dyeing Parameters, EUROGRAPHICS 2007 , EUROGRAPHICS2007 shortpapers and medical prize awards, pp.85-88, 2007, 2007.09.
34. Akihiko SHIRAI,Kyoko MURAKAMI,Reiji TSURUNO,Etsuo GENDA, WiiMedia: Papier Poupee Painter";a new usage of game controller for infancy art media, CyberGames2007; International Conference on Games Research and Development, CyberGames2007:International Conference on Games Research and Development, Edmond C.Prakash and tosiyasu L. Kunii(Editors), pp.25-32, 2007
e-Book Published in 2007 at Cybergames Converence, Manchester Metropolitan University, Departmentof computing and Mathematics, manchester M1 5GD , 2007.09.
35. Yuki Morimoto, Reiji Tsuruno, Kiyoshi Tomimatsu, Liquid Penetration Modeling for Cloth Dyeing, Computational Aesthetics in Graphics, Visualization and Imaging, D.W.Cunningham,G.Meyer,L.Neumann(Eds), Eurographics Association, pp.97-104, 2007, 2007.06.
36. Maki Terai, Jun Fujiki, Reiji Tsuruno, Kiyoshi Tomimatsu, Tile-Based Modeling and Rendering, A.Butz et al.(Eds.), Springer-Verlag, SG 2007, LNCS 4609, pp.158-163, 2007 8th International Symposium on Smart Graphics, Kyoto, Japan, June 2007, Proceedings, LNCS 4609, pp.233-234, 2007, 2007.06.
37. Yuki Morimoto, Reiji Tsuruno, Cellular Modeling of Dye Stain on Cloth, International Journal of Asia Digital Art and Design, vol.5,pp.20-25, 2006.12.
38. Kyoko Murakami, Reiji Tsuruno, Etsuo Genda, Natural-looking strokes for drawing applications, The Visual Computer, vol.22, pp.415-423, 2006.05, [URL].
39. Jun Fujiki, Kyoko Murakami, Reiji Tsuruno, Kiyoshi Tomimatsu, Path Tracing in Volumetric Space Using Stored Irradiance, IWAIT2006(International Workshop on Advanced Image Technology), pp.256-261, ISSN1880-5957, 2006.01.
40. Masaaki Matsumura, Reiji Tsuruno, Visual Simulation of Melting Ice Considering the Natural Convection, ACM SIGGRAPH, sketches, SIGGRAPH2005
conference proceedings DVDROM, 2005.07.
41. Cellular Modeling of Dye Stain on Cloth.
42. Visual Simulation of Melting Ice Considering the Natural Convection.
43. Kyoko Murakami, Reiji Tsuruno, Etsuo Genda, Multiple Illuminated Paper Textures for Drawing Strokes, IEEE, Proc. of Computer Graphics International 2005 (CGI'05)
June 22024,2005, Stony Brook, NY, USA
pp.156-161, 2005.06.
44. Be Silhouetted : Invisible and Visible Shadow.
45. Strokes for Drawing Tools Using Illuminated Paper Surfaces..
46. Kyoko Murakami, Reiji Tsuruno, Etsuo Genda, Strokes for Drawings Using Illuminated Paper Surfaces, SIGGRAPH2004 Full Conference DVD-ROM, 2004.08.
47. Pastel Drawing-like Rendering and Animation Considering Frame-to-Frame Coherence.
48. Kyoko Murakami, Reiji Tsuruno, Trans-Polygon Stroke Method for Frame Coherent Pastel Images, Eurographics 2003 short presentation, 2003.09.
49. Kyoko Murakami, Reiji Tsuruno, Polygon-based Pastel-like Rendering for Animation, SIGGRAPH2003 conference proceedings DVD ROM, 2003.07.
50. Kyoko Murakami, Reiji Tsuruno, Pastel-like Rendering Considerign the Properties of Pigments and Support Medium, SIGGRAPH2002 conference abstract and applications, p.227, 2002/7, 2002.07.
51. Pastel-like Rendering Considering the Properties of Pigments and Support Medium.
52. Shunji HIrokawa, Reiji Tsuruno, Computer Generated Graphic Images of Human Ligament, The VIII-th International Symposium on Computer simulation in Biomechanics, Proc.of the VIII-th International Symposium on Computer simulation in Biomechanicspp.59-64, 2001/7, Milan, Italy, 2001.07.
53. Hirokawa, S., Reiji Tsuruno, Three-dimensional deformation and stress distribution of the anterior cruciate ligament in the knee (Results of model analyses and visual simulation), JSME International Journal, Series C: Mechanical Systems, Machine Elements and Manufacturing, 43, 4, 957-965, Volume 43, Issue 4, December 2000, Pages 957-965, 2000.12, This paper describes a new structurally-motivated phenomenological approach. Such assumption was made that the ACL can be idealized as being composed of a homogeneous matrix in which two non-interacting families of densely distributed extensible fibers are embedded. Then a constitutive equation for the ACL composite was formulated. Using the finite element method, the visual simulations were performed in terms of three-dimensional change in shape, stress distribution and intraligaments' stresses, as a function of knee angle. Variations in stress due to tibial anterior-posterior displacements were also introduced. All the results were compared and discussed with the previous studies, thereby verifying the validity and usefulness of our model..
54. Mechanism of the MCL Injurie
Journal of Japanese Society for Clinical Biomechanics
Vol.21, pp171-178,2000.
55. Yoshida, M., Kamiura, Y., Reiji Tsuruno, Takahashi, M., Tomokage,H., Application of one-bond-type migration to interstitialcy-type self-interstitial and phosphorus in silicon, Journal of Crystal Growth, Volume 210, Issue 1, 1 March 2000, Pages 128-131, 2000.03, (1) From the standpoint of the potential energy, the one-bond-type migration is divided into the BC (bond-centered type) and SP (split 〈1 0 0〉 type) migrations. In the BC migration, there are two kinds of atom migrations. One is that in which a BC atom pushes its neighboring atom to a BC site. This is the typical migration by the interstitialcy mechanism. The other is that in which a BC atom rotates about its neighboring atom and becomes the BC atom again. This is a feature of the BC migration. (2) The BC and SP migrations are applied to P diffusion in Si. Assuming there is no interaction between P and Si, the distance and probability for each step of the migration are obtained and applied to Si self-diffusion. Because they are not constant, the definition of the correlation factor for the self-diffusion is different from the usual one..
56. Shunji Hirokawa, Reiji Tsuruno, Three-dimensional Deformation and Stress Distribution in an Analytical/Computational Model of the anterior Cruciate Ligament, Journal of Biomechanics, 10.1016/S0021-9290(00)00073-7, 33, 9, 1069-1077, Vol.33, No.9, pp.1069-1077, 2000, 2000.01.
57. Visual Simulation on 3-D Deformation and Stress Distribution in the ACL.
58. It is assumed that an interstitial phosphorus atom and a self-interstitial, Pi and I, are of the interstitialcy type. One bond-type migration is applied to their migration. It is concluded that there is essentially no difference between the migrations of a P-I pair, (PI), and Pi by the interstitialcy mechanism and between the chemical processes for the formation-dissociation of (PI) and the kick-out mechanism of Pi..
59. Hirokawa,S., Reiji Tsuruno, Visual simulation on ligament's stress derived from the microstructural model, Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings, 20, 2478-2481, Volume 5, 1998, Pages 2478-2481
Publisher: IEEE, Piscataway, NJ, United States, 1998.01, This paper describes a new structurally-motivated phenomenological approach. Such assumption was made that the ACL can be idealized as being composed of a homogeneous matrix in which two non-interacting families of densely distributed extensible fibers are embedded. A non-linear stress-strain characteristic exhibited by multiple collagen fibers was represented by the tri-liner curve. Then a constitutive equation for the ACL composite was formulated. Using the finite element method, a 3-D finite deformation and stress distribution of the ACL as a function of knee flexion were introduced through simulation and their graphic representation was made..
60. Migration of interstitialcy-type self-interstitial is considered to be the repetition of breaking a bond and forming a new bond. Based on this, if a split-〈100〉 self-interstitial is most stable, it migrates via a bond-centered self-interstitial. If a bond-centered self-interstitial is most stable, it migrates via a split-〈100〉 self-interstitial..
61. Shunji Hirokawa, Reiji Tsuruno, Hyper-Elastic Model Analysis of Anterior Cruciate Ligament, Medical Engineering and Physics, 10.1016/S1350-4533(96)00077-X, 19, 7, 637-651, Vol.19, No.7, pp.637-651, 1997, 1997.01.
62. Hirokawa, S., Reiji Tsuruno, Measurement/analysis of deformation and strain distribution of the anterior cruciate ligament in the human knee, Memoirs of the Kyushu University, Faculty of Engineering, Volume 56, Issue 2, June 1996, Pages 51-68, 1996.06, Highly variable deformations of the anterior cruciate ligaments (ACL) cannot be adequately quantified by one-dimensional and/or localized measurements. Furthermore it is impossible to directly measure in-situ, non-uniform distribution of biaxial strain over the entire surface of the intra-articular ligaments. We employed an alternative approach; Instead of using an actual knee and ACL, a knee motion simulator and a pseudo ligament were prepared. The pseudo ligament was manipulated so as to simulate the deformation and stress the actual ACL undergoes during knee flexion. Two hundred and ten points drawn on the pseudo ligament at regular intervals, were measured by the stereo-photogrammetric method, and components of the Green strain tensor were computed. Next, using the finite element method, in which the ligament was treated as an incompressive hyperelastic membrane, the finite deformation of the ligament was theoretically analyzed. The results demonstrated that strain distribution varied, even along the fiber run, and large strain gradients were observed in the regions near the insertions. Futher, the following values were obtained as a function of knee flexion: three-dimensional change in shape, resultant pull force on the tibial insertion, and change of strain pattern by anterior-posterior displacement of the tibia..
63. Reiji Tsuruno, Isobe Yoshihide, Ozaki Shin, Kosako Hideo, Bamba Eiichi, Computer design system of compensating filter for radiography treatment, Systems and Computers in Japan, Volume 25, Issue 3, March 1994, Pages 68-77, 1994.03, The following problem sometimes arises in the radiation treatment of a pathological area in the human body. Due to the nonuniformity of thickness and the difference of density of the tissue passed by the radiation energy, the radiation dose in the target area may not be uniform. To avoid such a situation, this paper considers a method in which the attenuation configuration of the radiation in passing through the body is estimated in detail. A three-dimensional block is placed between the radiation source and the target area to realize the radiation treatment with the dose correction. The design method for the three-dimensional block, i.e., the compensation filter for the correction, is discussed. First, the CT value for each density voxel obtained by the continuous tomography of X-ray CT image is converted into the absorption coefficient of the high-energy X-ray for treatment. Then the values of the voxels passed from the radiation generator to the pathological area are summed up, and the radiation dose in the target areas is calculated. The three-dimensional shape of the compensation filter, which can correct adequately the dose distribution, is determined based on the tissue-air dose ratio obtained from the actual measurement. The block is constructed based on the shape data. By the experiment using a phantom, the nonuniformity of the dose is reduced approximately from 10 percent to 3 percent. In the simulation for the application to the biological object, the area of high dose distribution fits the target area, indicating the effectiveness of the dose correction..
64. Matsui,Nobuyuki, Reiji Tsuruno, Bamba Eiichi, Fractal dependence of texture perception, Systems and Computers in Japan, Volume 25, Issue 7, 1 January 1994, Pages 82-91, 1994.01, Presented in this paper are recognition experiment and attention allocation model through simultaneous presentation of multiple images, where a set of textures with known fractal dimensions are used as the image information. The relations are examined quantitatively. From the results, it is verified that the fractal information can be used as the pop-out discrimination element in the recognition of the texture.
65. Kazuhiko Ushio, Reiji Tsuruno, Cyclic Sk-Factorization of  Complete Bipartite Graphs, SIAM (Society of Industrial Applied Mathematics), 557-563, 1991.09.
66. Kazuhiko Ushio, Reiji Tsuruno, P3-factorization of complete multipartite graphs, Graphs and Combinatorics, Springer Verlag., , 5, 1, 385-387, 1989.02.