We present the Langevin rigid approach, a technique for animating the dynamics of immersed rigid bodies in viscous incompressible fluid in real-time. We use generalized Kirchhoff equations to ensure forces and torques from the surrounding fluid that create realistic motion of immersed rigid bodies. We call our method the Langevin rigid approach because the generalized Langevin equations are applied to represent the effects of turbulent flow generated at the body surface. The Langevin rigid approach precomputes added-mass effects and the vortical loads from turbulent model, and executes the rigid body solver in runtime, so that this method is straightforward and efficient to the interactive simulations. Many types of rigid bodies with lightweight mass （e.g. leaf or paper） can be simulated realistically in high-Reynolds-number flows.

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Condition of skin is an important factor for the impression of faces. Well-cared skins give shiny and beautiful impression, while dry and rough skins loss the gloss and therefore they are less attractive. These differences often attribute to the difference of their micro-geometry. Such micro-geometry of human skins consists of furrows forming a mesh, ridges surrounded by the furrows, and pores. This paper presents a technique for micro-geometry simulation of human skins. The technique first generates pores forming a pattern of a well-aligned triangular grid. It then divides the skin region by applying the Delaunay triangulation algorithm to connect the pores. It treats the triangles as ridges, and the edges as furrows. Finally, the technique divides the pattern into a finer triangular mesh, so that it can finely represent 3D geometry of pores, ridges, and furrows. This paper also presents a technique for image recognition of micro-geometry parameters of real human skins. It features two-steps of template-matching- like algorithms: the former one acquires sizes of pores, and the latter one acquires widths and directionality of furrows. These results are consumed by the skin simulation technique as input parameters of the micro-geometry.

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In most cases, earthenware is broken when it is excavated from ruins. This situation requires restoration for assembling the earthenware's pieces. The point clouds measured by a three-dimensional device are useful to restore the earthenware. Some methods to find adjacent pieces of earthenware using a computer have been proposed. These methods aim to restore broken earthenware by connecting adjacent pieces with using digital data. If, however, earthenware with large missing portions is restored, it is impossible to estimate the adjacent piece using local adjacency. Due to this, it is necessary to estimate the whole shape of earthenware. It is also possible to continue sequential local estimation for estimating whole shape of earthenware, but the distortion occurs in many cases. In this paper, we propose a method to estimate the whole shape of earthenware with quadric surfaces. Since most earthenware is produced to be as close as rotational shapes, quadric surfaces are suitable to represent rotational shapes. In our method, the uneven pattern on the surface is removed in the first step according to the Taubin's smoothing method. Next, the point cloud from which uneven patterns are removed is divided into several groups. After that, each point cloud is fitted to quadric surfaces represented by the algebraic equation. Finally, the sequences of points generated from quadric surfaces are interpolated and the free-form surfaces corresponding to the surface of the earthenware are generated.

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In this paper, we conducted experiments to verify depth effects by audio and visual information in the representation of a planar view of a two-dimensional space in a tablet computer such as an iPad, and proposed some methods to amplify the operator's sense of depth perception. In the visual information, three types of amplifying methods were investigated in a two-dimensional space: kinetic depth effect, linear perspective, and air perspective. In the audio information, we also investigated three types of amplifying methods: depth effect with time difference between audio information and visual information, the effect of depth by differences in sound intensity, and the depth effect due to the reflected sound. As a result, we could obtain an audio image with a sense of depth based on these effects even with a monaural speaker. We found that the most effective depth perception was obtained from the linear perspective for visual information, and with differences in sound intensity for audio information. In addition, audio information had a threshold value which did not occur in the visual information. When the level of audio information was over the threshold value, it was found that depth perception effects decreased.

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In this study, we propose a method for simulating tree growth that considers several features of a tree's surface. The phenomena of cell division are considered for simulating tree growth. To simulate tree's growth, a tree is modeled as a polygonal mesh that grows by displacing the vertices of the polygonal mesh. Changing speed of the displacing, several tree's surfaces are generated. In this study, we focus on knots, hollows, and extra wood caused when tree growth encounters an immovable object. Knots are generated by unusual and uneven growth of the cambium cells; a hollow is caused by rotten unsound xylem; and extra wood is made to protect the body. To define a tree shape, branching structures of trees are controlled by parametric L-system, and surface shapes are specified by some parameters. Subsequently, we generate tree models with several surfaces, including burls, hollows, and extra wood.

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We have proposed a color extraction method from text with a database expressing the relationships between adjectives and 130 colors to create an abstract image that reflects people impressions. We applied this method to movie reviews, replaced colors of movie posters with extracted colors from the method, and performed an experiment with 50 participants. By showing the poster created by our method to participants, the movie with lower comprehensive evaluation could get higher satisfaction keeping the same level of expectation, and the movie with higher comprehensive evaluation could get higher expectation keeping the same level of satisfaction.

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This paper proposes a Virtual Reality application for playing with blocks. Players can create their own decorative castle in a virtual world, by only stacking simple physical blocks in the system. We designed a tangible interface such that a player can experience seamless interaction between the real world and a virtual world when playing with toy blocks. The system gives players a revolutionarily enjoyable experience where blocks are stack in the real world and blocks stacked in the real world are dynamically transformed into a castle in a virtual world. The system enables players to create a realistic castle that reflects the shape of the blocks. Moreover, the system smoothly connects the physical world to the virtual world by means of a tangible interface and real-time computer graphics. The system was exhibited at domestic and international conferences. The evaluation of the system was done survey by a carried out using questionnaire at the event. The evaluation found that the system was easy to play and most of the players enjoyed the system.

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