• Journal of KSNVE
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• v.4 no.1
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• pp.83-88
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• 1994

In many circumstances, it is desired to move a mass from one position to another without inducing and vibration in the mass being moved. Two such problems are considered here : the motion of a mass initiated by another mass, nd the motion of a pendulum initiated by the specified motion of its support. In each case, it is dosired that the system start at rest and come to rest in the second position. A simple strategy for the specified motion is given here. The method is motivated by engine cam-follower design. The force required to move the system in question is determined as well as the maximum value of the force required(and the times at which these forces take place).

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.1
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• pp.91-96
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• 2003

The forces and moments at the aircraft c.g. have components due to aerodynamic effects and to engine thrust. For the flight stability and autopilot systems we present a attitude control method using an intelligent control algorithm Which is based on the control rules from experts knowledge concerning the motion equations and other experiences. Then a robust fuzzy controller is developed to control the flight attitude. The controller can deal with multiple inputs and outputs. We have made an aircraft model and the orientation sensor for experimental flights. The control rules based on the flight expert s experience and knowledge can be programmed by fuzzy rules, and determined control rules by experimental flight. We can be stable attitude control by fuzzy controller.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.12
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• pp.77-86
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• 2015

It is difficult to extract small valve automatically in noisy 3D point cloud obtained from LIDAR because small object is affected by noise considerably. In this paper, we assume that the valve is a complex model consisting of torus, cylinder and plane represents handle, rib and center plane to extract a pose of the valve. And to extract the pose, we received additional input: center of the valve. We generated histogram of distance between the center and each points of point cloud, and obtain pose of valve by extracting parameters of handle, rib and center plane. Finally, the valve is reconstructed.

• Journal of Ocean Engineering and Technology
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• v.13 no.2 s.32
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• pp.138-146
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• 1999

The viscous flow around a ship hull is calculated by the use of RANS(Reynolds-averaged Navier-Stokes) solver. Reynolds stresses are midelled by using the k-${epsilon}$ turbulence model and the law is applied near the body. Body fitted corrdinates are introduced for the treatment of the complex boundary of the ship hull form and the governing equations in the physical domain transformed into ones in the computational domain. The transformed equations are numerically solved by an employment of FVM(Finite Volume Method). SIMPLE(Semi-Implicit Pressure Linked Equation) method is adopted in the calculation of pressure and the solution of the sidcretized equation is obtained by the line-by-line method with the use of TDMA(Tri-Diagonal Matrix Algorithme). To assure the proprietty of this computing method, HSVA tanker and Dyne hull are calculated ar both model and ship scale Reynolds number. Their reaults of pressure distributions on fore and aft body, axial velocity contours and transverse velocity velocity vectors and viscous resistance coefficients are compared with other's experiments and calculations.

• Journal of Navigation and Port Research
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• v.28 no.8
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• pp.753-757
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• 2004

The free-surface flow is simulated to make clear the viscous interaction of stem waves and the sub-breaking phenomena around a high speed vehicle. The Navier-Stokes equation is solved by a finite difference method where the body-fitted coordinate system, the wall function and the triple-grid system are invoked They are applied to study precisely on the stem flow of S-103 as to which extensive experimental data are available. Computations are extended to the submerged revolutional body. The numerical result shows that the gradient of M/Us is greatly influenced by the submerged depth And the stem wave is influenced by the separation due to the bow wave.

• Journal of the Korea Society of Computer and Information
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• v.4 no.3
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• pp.60-66
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• 1999

The purpose of this study is to design and materialize the simulated courseware which is based on new educational environments and student-based education. The scope of this study is reflection and refraction of in the physics of high school. This paper introduce the theoretical background of courseware and investigate the structure and process of the teaching-theory by visualized computer simulation. We applied the basic concept about the reflection and refraction of light and explained the simulated images of spherical mirror and lens with the principles expressions and relative image forms. The last we simulated the various kinds of the images, shapes and distance of the images by changing the distance of object and focus which are made by computer simulation.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.141-146
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• 2005

This paper an application example of PIV system for analyzing the flow of submerged structure. In this paper, we introduce an analysis method to predict the characteristics of flow around the neighboring fields of tetrapod and fishing reef in order to develop a high performance model. Flowing phenomenon according to velocity distribution and flow separation around the submersed body were obtained by PIV system. Flow visualization has conducted in a circulating water channel by a high speed camera and etc.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.372-376
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• 2008

Nowadays, active teachers expend much time and effort in preparing for classes. Especially, the basic formative calsses in art education have much effect when they are done with a lot of material(plaster casts, etc.) and lighting effect, but not in real. Proposed web-based learning instrument makes possible basic formative classes with simple operation by loading several materials and lighting operator on the web. In this paper, we propose web-based learning instrument to improve basic formative classes. Students will easily be able to express shadow and shade by lights with this web-based learning instrument in basic formative classes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.2
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• pp.126-130
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• 2002

This paper presents the basic concept of new solid freeform fabrication system using rapid prototyping method. The system could fabricate an arbitrary ceramic form by laser cutting, transferring, stacking, and sintering of each slide. The system consists mainly of laser apparatus. X-Y table, a slide transferring system, and electric oven. The system could fabricate an object that has smooth surface with comparatively short period of time. The system is effective in terms of its direct fabrication capability without second mechanical process. The fabricated shape could directly be used as part of a whole assembly and therefore its method could be applied to various application areas.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.3
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• pp.416-421
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• 2008

This paper realizes a system that recognizes traffic safety signs by applying the principle used for game in reverse. The game used for this paper is one that expresses the shape of temporary objects intended by the maker when the maker sees the numerical image provided on (x, y) coordinates and then expresses it on the mesh. After separating the traffic safety sign image from the input image, the system is realized by outputting the content of the sign into letters by recognizing the forms and colors constituting the sign using the puzzle game above. Our system has fast process time and better rate of recognition than the existing system with black-and-white image processing and recognition without any penciling progress.