• 한국통신학회논문지
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• 제31권3C
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• pp.264-270
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• 2006

In this paper, we propose the modified display color control system using white point line, boundary lines and S-shaped curves to emphasize blue and red tone colors on CIE1931 diagram. The proposed system divides RGB gamut into movable area and non-movable area by using boundary lines. The colors in movable area are moved into right side or left side along quadratic curve to change the bluish (or reddish) color to more bluish (or more reddish), while those in non-movable area are excepted from color control to prevent skin color from changing. The loci of the quadratic curves are very similar to the arc of the white-point line which connects all points that represent the chromaticities of a black body radiator at different temperatures and is also called the black body locus. The RGB gamut extension by movement of chromaticity coordinate can improve color reproducibility. Therefore in the case of application to LCD, the display shows excellent performance because the LCD's color reproducibility is comparatively lower than that of other display systems. The proposed system is also experimentally demonstrated with Xilinx Virtex FPGA XCV2000E- 6BG560 and the TV set.

• 대한조선학회논문집
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• 제48권1호
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• pp.23-32
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• 2011

Numerical analysis of hydrodynamic performance of a movable submerged breakwater was carried out as an eco-friendly marine structure for coastal and harbor protection. Using boundary elements method with two-dimensional frequency-domain reflection and transmission coefficients and wave forces acting on the submerged flat plate were calculated with various submerged depths and respective motion allowable modes. The movable breakwater was found to be more efficient in wave-blocking than the fixed structure. Variation of reflection coefficients was significantly influenced by vertical motion of the body.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.480-485
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• 2008

In this study, two types of ramjet intake were designed for the flight condition of Mach number 2 and 5 and numerical analysis was performed. In order to widen the flight envelope range(Mach number $2{\sim}6$), movable intake concept was applied. The central body was designed so that the capture area ratio which is one of most important factors of ramjet intake design could be adjusted. And various types of cowl and movable insert part of shell were designed in order to control throat area which could increase total pressure recovery. The numerical results showed that the designed ramjet intake could be applied in various flights Mach number.

• Journal of Multimedia Information System
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• 제7권4호
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• pp.269-276
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• 2020

The small craft including jet-board for leisure are commonly smaller than the general commercial vessels. For the floating vessel, the motion analysis is significantly important component to design the shape. It is, however, hardly predicting its behavior by using conventional boundary element method due to violating small amplitude assumption for potential theory. The computational fluid dynamics method can afford to simulate such small craft, but its grid system was not able to calculate motion, because movable body disturbs the grid system by confliction. The dynamics fluid body interaction model with over-set mesh system can be dealt with movable floating body under irregular ocean wave. In this study, several cases were considered to reveal that DFBI is essential method to predict floating body motion. The single phase simulate was conducted to establish the shape perfection, and then the validated vessel was simulated with ocean waves weather DFBI option on or off. Through the comparison, the results between the cases of DFBI on and off shows significantly difference. It was claimed that the DFBI was necessary not only to calculation body motion, but also to predict accurate drag and lift force on the floating body for small size craft.

• 산업경영시스템학회지
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• 제29권4호
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• pp.1-7
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• 2006

This study determined the optimal positions of the movable steering wheel and pedal systems of industrial vehicle by various body dimensions. The position of objects and starting driving posture were measured by Martin-type anthropometer and goniometer. The X, Y and Z axis of movable steering wheel and pedal systems were measured horizon distance from right side to left side, horizon distance from front side to rear side and vertical distance from floor to ceiling. During the experiment in order to exclude learning effectiveness with forklift driving, 27 subjects who had male not experiences in driving a forklift used in the experiment. The relationship between the position of steering wheel and driver's posture with body dimensions was analyzed by using correlation relation and paired comparison t-test based on the measured data. The pedal location in X and Z axises was not related with various body dimensions. Also, the steering wheel was different among the angles of the right elbow and shoulder depending on the various body dimensions.

• 대한조선학회논문집
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• 제49권4호
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• pp.287-295
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• 2012

Hydrodynamic performance of a movable submerged breakwater was analyzed using energy dissipation model. Based on two-dimensional boundary element method the equation of motion including a viscous dissipation term proportional to velocity squared was solved by Newton-Raphson method. Energy dissipation coefficients as well as reflection and transmission coefficients of a submerged flat plate were calculated with various plate lengths and thickness. Both real and imaginary components of body displacement and forces were used to solve the motion of breakwater accurately. The effect of the magnitude of dissipation coefficient on the body displacement was evaluated. The results from the potential theory with no dissipation term were found to be an overestimate in resonance frequency.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제30회 춘계학술대회논문집
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• pp.207-210
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• 2008

본 논문에서는 램제트 기관의 성능을 결정짓는 공기흡입구를 램제트 엔진의 비행 목적에 맞게 비행 마하속도 4에서 기본설계를 수행하였다. 순항고도 12km, Mach $2{\sim}6$의 넓은 영역에서의 운용을 가능하게 하기 위하여 가변형 공기흡입구의 개념을 도입하였다.

• Structural Engineering and Mechanics
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• 제86권6호
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• pp.751-764
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• 2023

In practical engineering such as aerial refueling pipes, the boundary of the fluid-conveying pipe is difficult to be completely immovable. Pipes under movable and immovable boundaries are controlled by different dominant nonlinear factors, where the boundary mobility will affect the nonlinear dynamic characteristics, which should be focused on for adopting different strategies for vibration suppression and control. The nonlinear dynamic instability characteristics of functionally graded fluid-conveying pipes lying on a viscoelastic foundation under movable and immovable boundary conditions are systematically studied for the first time. Nonlinear factors involving nonlinear inertia and nonlinear curvature for pipes with a movable boundary as well as tensile hardening and nonlinear curvature for pipes with an immovable boundary are comprehensively considered during the derivation of the governing equations of the principal parametric resonance. The stability boundary and amplitude-frequency bifurcation diagrams are obtained by employing the two-step perturbation- incremental harmonic balance method (TSP-IHBM). Results show that the movability of the boundary of the pipe has a great influence on the vibration amplitude, bifurcation topology, and the physical meanings of the stability boundary due to different dominant nonlinear factors. This research has guidance significance for nonlinear dynamic design of fluid-conveying pipe with avoiding in the instability regions.

• 한국해양공학회지
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• 제28권5호
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• pp.466-473
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• 2014

Underwater gliders do not have any external propulsion systems that can generate and control their motion. Generally, underwater gliders would obtain a propulsive force through the lift force generated on the body by a fluid. Underwater gliders should be equipped with mechanisms that can induce heave and pitch motions. In this study, an inner movable and rotatable mass mechanism was proposed to generate the pitch and roll motions of an underwater glider. In addition, a buoyancy control unit was presented to adjust the displacement of the underwater glider. The buoyancy control unit could generate the heave motion of the underwater glider. In order to analyze the underwater dynamic behavior of this system, nonlinear 6-DOF dynamic equations that included mathematical models of the inner movable mass and buoyancy control unit were derived. Only kinematic characteristics such as the location of the inner movable mass and the piston position of the buoyancy control unit were considered because the velocities of these systems are very slow. The effectiveness of the proposed dynamic modeling was verified through sawtooth and spiraling motion simulations.

• 대한가정학회지
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• 제42권1호
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• pp.99-113
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• 2004

To protect farmers from solar radiation and UV, the movable sunshade tent was designed and its protection efficiency was measured in the artificial chamber and outdoors. Sunshade tent and the existing farmer's hat were examined. The results were as followes； Heart rate, total body weight loss and temperature of clothing microclimate on the chest and the back were lower in using sunshade tent than those in wearing existing hat in two experiments. In subjective sensation, subjects answered to feel significantly hotter and more uncomfortable in wearing existing hat in two experiments. Rectal temperature was significantly lower using the sunshade hat in experiment at outdoors(p<0.001).