• Journal of the Korean Institute of Gas
• /
• v.2 no.1
• /
• pp.74-82
• /
• 1998

The grain boundary etching method as a technique for assessing degradation of structural materials used at elevated temperature has received much attention since it is simple, inexpensive and easy to apply to real plant components. In this study, the technique is applied to some aged petroleum and chemical plant components such as reactors and drums. As a degradation parameter, intersection number ratio ($N_i/N_o$), is employed. The intersection number ratio ($N_i/N_o$) is defined as the ratio of intersection number ($N_i$) obtained from 5-minute picric acid etched surface to the number ($N_o$) obtained from Nital etched surface. In order to study degradation level, several relationships were measured such as the correlation between shift in ductile brittle transition temperature, $({\Delta}DBTT)_{sp}$ and intersection number ratio, ($N_i/N_o$) and the correlation between the measured ($N_i/N_o$) values and Larson-Miller Parameter values.

• Proceedings of the Korea Contents Association Conference
• /
• 2007.11a
• /
• pp.894-898
• /
• 2007

Now a day, lots of the animations include TV series Animations are made by the technique of 3D Animation. However, 3D Animation obstructs visual elements and deteriorates an acquaintance with the limit of unfamiliar material methods and dispersion of light. For this reason, a large of number of 3D Animations are repacked with the style of 2D Animation. Most of previous studies for the conversion of output 3D Animation to the style of 2D Animation are analysis for 2D rendering techniques. In case of Non-realistic 3D Character Animation, first and foremost it needs investigation of the basic producing method for the 2D Animation is different with the realistic expression way of the one for the 3D animation. For a case study, expression methods for the non-realistic and the non-actuality 2D Character Animation come with impossible ways in the real life. This study for the 3D Animation with the style of 2D Animation is to investigate on the keynote for effective expression methods, when we turn 3D Animation into the style of 2D Animation.

• Journal of KIISE:Computer Systems and Theory
• /
• v.33 no.1_2
• /
• pp.128-136
• /
• 2006

The stippling techniques, which represent objects with numerous points using pen and ink. The previous stippling techniques for Non-Photorsealistc Rendering(NPR) use single-colored points to represent the tone of gray image ur the material of surface. This paper presents a new stippling technique with various colored points based on the analysis of color information. By using the color information of the input image on HSV model, we define the color weight function that allows to determine automatically the number and size of points. The color jittering based on Munsell's color model can generate stippling drawings using various colored points to represent the image. Our color stippling method is expected to be used in many areas such as animation, digital art, video processing and CG tool.

• Journal of the Korea Society of Computer and Information
• /
• v.29 no.6
• /
• pp.23-29
• /
• 2024

In this paper, we propose a fast GPU-based method for representing pore flow, absorption, emission, and diffusion effects represented by cloth-liquid interactions using smoothed particle hydrodynamics (SPH), a particle-based fluid solver: 1) a unified framework for GPU-based representation of various physical effects represented by cloth-liquid interactions; 2) a method for efficiently calculating the saturation of a node based on SPH and transferring it to the surrounding porous particles; 3) a method for improving the stability based on Darcy's law to reliably calculate the direction of fluid absorption and release; 4) a method for controlling the amount of fluid absorbed by the porous particles according to the direction of flow; and finally, 5) a method for releasing the SPH particles without exceeding their maximum mass. The main advantage of the proposed method is that all computations are computed and run on the GPU, allowing us to quickly model porous materials, porous flows, absorption, reflection, diffusion, etc. represented by the interaction of cloth and fluid.

• The Journal of the Korea Contents Association
• /
• v.10 no.2
• /
• pp.193-201
• /
• 2010

Being an element of plastic arts and a language of plastic forms, the color white has significant potential for improving the quality of physical environment. Colors are dealt with scientifically in chromatics, and also often become an interesting topic when analyzing a society and its history and culture. Thus, an in-depth study of the symbolism of color white and, of white pigment are required because the color has not only an important chromatic value and this should be understood a great deal, but also been the important symbol of a culture in a particular period. This paper examined the significance of the color white identified in Asian and Western cultures based on scientific and psychological understanding of the color. This also analyzed a few major white pigments, then demonstrated different methods of using the pigments and various techniques of expression used by Asian and Western painters. In addition, the paper attempted to raise awareness of the color white as chromatic color over non-color by examining the contrasting viewpoints on the color, and the changes in the viewpoints over time and place.

• Journal of the Korea Computer Graphics Society
• /
• v.18 no.2
• /
• pp.55-62
• /
• 2012

This paper presents a new method to represent the secondary deformation effect using simple mass-spring simulation on the vertex shader of the GPU. For each skin vertex of a 3D character, a zero-length spring is connected to a virtual vertex that is to be rendered. When a skin vertex changes its position and velocity according to the character motion, the position of the corresponding virtual vertex is computed by mass-spring simulation in parallel on the GPU. The proposed method represents the secondary deformation effect very fast that shows the material property of a character skin during the animation. Applying the proposed technique dynamically can represent squash-and-stretch and follow-through effects which have been frequently shown in the traditional 2D animation, within a very small amount of additional computation. The proposed method is applicable to represent elastic skin deformation of a virtual character in an interactive animation environment such as games.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.11
• /
• pp.81-87
• /
• 2022

In this paper, we propose diffraction-based sound control method to improve sound immersion in a virtual environment. The proposed technique can express the wave and flow of sound in a physical environment and a pattern similar to diffraction in real-time. Our approach determines whether there is an obstacle from the location of the sound source and then calculates the position of the new sound reflected and diffracted by the obstacle. Based on ray tracing, it determines whether or not it collides with an obstacle, and predicts the sound level of the agent behind the obstacle by using the vector reflected and refraction by the collision. In this process, the sound attenuation according to the distance/material is modeled by attenuating the size of the sound according to the number of reflected/refracted rays. As a result, the diffraction pattern expressed in the physics-based approach was expressed in real time, and it shows that the diffraction pattern also changes as the position of the obstacle is changed, thereby showing the result of naturally spreading the size of the sound. The proposed method restores the diffusion and diffraction characteristics of sound expressed in real life almost similarly.

• Journal of Digital Convergence
• /
• v.13 no.11
• /
• pp.331-336
• /
• 2015

The texture mapping used for the low-polygon models is one of the important workflows in the graphical representation of the 3D game. Only one hand painted texture is mapped on the surface of the 3D model and represents the color of the material and visual sense of touching by itself in that process. In the 3D game graphics, it is very important to visualize the textile sensation such as protruding and denting. It can be interpreted by the Gestalt Law to recognize a plane as a 3D sense of volume. Moreover, the concept of Affordance is necessary to recognize and perceive the textile sensation. It means visual recognizing of that relationship in the learning process. In this paper, The questionnaire survey targeting 3D game graphic designers is carried out. By analyzing the survey results, we suggest the important characteristic in the process of making hand painted texture.

• Science of Emotion and Sensibility
• /
• v.11 no.2
• /
• pp.173-180
• /
• 2008

In this research, experiments were performed to focus on haptical factors among the emotional way of expression in design, and, find out what factors of preference influenced by haptic elements as surface material, grip senses and shape that considering clues when consumer has purchase intention. The questionnaire survey of beverage bottles in experiment extract to haptic elements were estimated in various surface of bottles and consumer preference through practical touch by managed objects themselves. The experimental groups for this survey, one is using sight and sense of touch both, the other groups are use sense of touch only without sense of sight. Therefore, to find out effective factors for design and functional matter as the kind of treating surface and properties derived from comparing two experimental groups have recognition in level of priority for each element related with haptical design sources. Finally, considering practical use schema with emotional approach based on haptical property to adopting design process.

• The Journal of the Korea Contents Association
• /
• v.6 no.8
• /
• pp.175-183
• /
• 2006

In computer graphics, according as the rapid development of hardware can realize high-resolution image on the monitor, the more natural and accurate rendering skill is needed gradually, and the studies about high-level rendering algorithm are processing. There are two types in rendering skill. The one is photo-realistic rendering to realize accurate image like photos and the other is real-time rendering to realize rapid real-time render. This paper includes caustics expression about lights and materials of several photo-realistic rendering skills. First this paper analyzes how caustics is used and expressed in movies, and further realizes caustics effect using real renderer. This paper examines objective criterion and capability of plug-in through the objective experiment of renderer. Also this paper analyzes using environment on variables for caustics effect realization. The experimental results can be applied to many rendering works as useful data, and can be used as data to understand characteristic and capability.