• 한국항해항만학회지
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• 제27권2호
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• pp.193-198
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• 2003

일점계류된 선박의 외력에 의한 불안정 거동을 경감시키는 방법에 대하여 검토하였다. 계류된 선박의 수치계산 시뮬레이션을 위해 조종운동방정식을 사용하였고, 선박에 가해지는 외력으로는 풍력과 파강제력이 고려되었다. 파강제력은 3차원특이점분포법에서 얻어진 주파수전달함수로부터 시간영역해석법을 적용하였고, 풍력은 OCIMF(1994)에서 제시한 값을 사용하였다. 계류된 선박의 안전대책으로 바우스러스터를 이용한 제어방법, 두 번째 묘를 이용한 굴레(Birdle)를 씌우는 묘박법이 검토되었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권1호
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• pp.446-467
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• 2012

In this paper, the analysis and design of a motion simulator (based on the approach taken by interactive virtual reality (VR) entertainment systems) is conducted. The main components of the system include a bilateral control interface, simulation and a motion simulator control scheme. The space entertainment system uses a virtual environment that enables operators to feel the actual feedback sensing and distorted motion from the virtual environment, just as they would in the real environment. The space entertainment system integrates the dynamics of the motion simulator and the virtual environment and the operator maneuvers a steering wheel to interact with the system. The multiple bilateral control schemes employ a dynamical controller, which is designed by considering the velocity and acceleration that the operator imposes on the joystick, the environmental changes imposed on the motion simulator. In addition, we develop a calculated method to evaluate the Ratio of the simulation results. It is shown that the proposed control scheme can improve the performance of the visual entertainment system. Experiments are conducted on the virtual reality entertainment system to validate the theoretical developments.

• 한국컴퓨터그래픽스학회논문지
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• 제23권1호
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• pp.33-38
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• 2017

본 논문에서는 이구아나의 저 품질 동작 포착 데이터를 이용하여 고 품질의 애니메이션을 시뮬레이션 하는 방법을 제안한다. 적은 수의 마커를 부착하여 포착한 이구아나의 동작 데이터는 실제 움직임을 정확히 표현하지 못하고, 이 데이터에 스킨 매시(Skinned Mesh)를 입히더라도 부족한 자유도 때문에 부자연스러운 움직임을 보인다. 위와 같은 문제를 해결하기 위하여 스킨 매시의 움직임을 근육과 몸체의 탄성력으로 모델링하는 연체 시뮬레이션(Soft Body Simulation)기법을 응용하여, 자연스럽고 유연한 움직임을 시뮬레이션 하는 과정을 본 논문은 소개한다. 이구아나의 다양한 이동 방법을 표현하기 위하여 동작 포착 데이터로부터 동작 그래프(Motion Graph)를 만들고, 이를 동작 생성시 상황에 적합한 동작을 선택하는데 활용한다. 지형 위에 사용자가 입력하는 좌표를 기초로 이구아나의 목표지점을 설정하고, 이를 바탕으로 그래프 경로를 계획한다. 그 결과 생성된 평지 위를 걷는 이구아나의 동작은 불규칙한 높이를 지닌 지형 위에서 적합한 동작으로 변형 된다. 이와 같이 지형에 적응된 동작은 연체 시뮬레이션 시 필요한 목표 근육길이를 계산하는데 활용된다. 마지막으로 연체 시뮬레이션 기업을 적용하여 다양한 상황에 대응 가능한 이구아나 물리 시뮬레이션을 구현하였다.

• 한국실내디자인학회논문집
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• 제14권6호
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• pp.112-119
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• 2005

Virtual reality(VR) is the technology that makes a user regard being in virtual space generated by computer as in the real world. Mainly, it has been studied about the three senses which are the sense of vision, touch and hearing in the five human senses. Through that, it is applied to the system making all the senses in the human body real. Even though the design idea of theater is brought to that of simulation theater, there are not many similarities between them and not general design rules yet. For making a better situation, in cooperation with a domestic company making a motion simulator for one or two person by itself, I have considered the minimum conditions and formations of the simulation theater being widely useful in the buildings of general commercial spaces from the environmental viewpoint, and basing on that facts I try to make some sorts of fundamental design types so that they are more available than those in the past. In this research, I have set the three types of simulation theater, the 50 seats of motion simulator for one person, the 20 seats of motion simulator and the 50 seats for two persons, in my researching range. Moreover, regarding the size of the simulation theater, I put the best specifications in order and also put them together, and then with making standards able to be reflected on the design plan, I have researched it for the purpose of the accumulation of skill in the construction of the special theater. Here, the design rule I suggested might be a design standard that it will be thought useful widely.

• 한국항해항만학회지
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• 제34권4호
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• pp.271-279
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• 2010

The Mobile Harbor(MH) is a new transportation platform that can load and unload containers to and from very large container ships in the sea. This loading and unloading by crane can be performed with only very small movements of the MH in waves because MH is operated outside of the harbor. For this reason, an anti-rolling tank(ART) and an active mass driving system(AMD) were designed to reduce MH's roll motion, especially at the natural frequency of MH. In the conceptual design stage, it is difficult to confirm the design result of theses anti-rolling devices without modeling and simulation tools. Therefore, the coupled MH and anti-rolling devices' dynamic equations in waves were derived and a simulation program that can analyze the roll reduction performance in various conditions, such as sea state, wave direction, and so on, was developed. The coupled equations are constructed as an eight degrees of freedom (DOF) motion that consists of MH's six DOF dynamics and the ART's and AMD's control variables. In order to conveniently include the ART's and AMD's control dynamics in the time domain, MH's radiated wave force was described by an impulse response function derived by the damping coefficient obtained in the frequency domain, and wave exciting forces such as Froude-Krylov force and diffraction force and nonlinear buoyancy were calculated at every simulation time interval. Finally, the roll reduction performances of the designed anti-rolling devices were successfully assessed in the various loading and wave conditions by using a developed simulation program.

• 대한인간공학회지
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• 제18권3호
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• pp.141-152
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• 1999

In this paper, We performed the human body dynamic modelling for the realistic animation based on the dynamical behavior of human body, and designed controller for the effective control of complicate human dynamic model. The human body was simplified as a rigid body which consists of 18 actuated degrees of freedom for the real time computation. Complex human kinematic mechanism was regarded as a composition of 6 serial kinematic chains : left arm, right arm, support leg, free leg, body, and head. Based on the this kinematic analysis, dynamic model of human body was determined using Newton-Euler formulation recursively. The balance controller was designed in order to control the nonlinear dynamics model of human body. The effectiveness of designed controller was examined by the graphical simulation of human walking motion. The simulation results were compared with the model base control results. And it was demonstrated that, the balance controller showed better performance in mimicking the dynamic motion of human walking.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1573-1576
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• 2008

A simulation system is developed to calculate the apparent motion-induced image from a sequence of temporal luminance transitions, while using the properties of the human visual system. Based on the simulation method, both edge (moving block) and detail degradation (line spreading, grating, sinusoidal pattern), and also color aberration are discussed.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.330-333
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• 2009

This paper proposes a method to estimate the flow speed of pedestrians in surveillance videos. In the proposed method, the average moving speed of pedestrians is measured by estimating the size of real-world motion from the observed motion vectors. For this purpose, pixel-to-meter conversion factors are calculated from camera geometry. Also, the height information, which is missing because of camera projection, is predicted statistically from simulation experiments. Compared to the previous works for flow speed estimation, our method can be applied to various camera views because it separates scene parameters explicitly. Experiments are performed on both simulation image sequences and real video. In the experiments on simulation videos, the proposed method estimated the flow speed with average error of about 0.1m/s. The proposed method also showed a promising result for the real video.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.234-237
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• 2008

A direct numerical simulation (DNS) code suitable for the prediction of buoyant jet diffusion flames was developed in this study. The thermodynamic and transport properties were evaluated using CHEMKIN package to enhance the prediction performance of the developed DNS code. A two dimensional simulations were performed for the jet diffusion flames in normal and zero-gravity conditions where the Froude numbers are 5 and infinity, respectively. The simulated buoyant jet diffusion flame in normal gravity showed that the unsteady and dynamic motion although the reynolds number is low (400). It was identified that the flame in normal gravity flickered periodically. The periodic motion of the flame disappeared in zero-gravity condition. The dynamic motion of the buoyant jet diffusion flame could be well understood by comparing the flame structures obtained by the simulations of normal and zero-gravity conditions.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2002년도 추계 학술대회논문집
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• pp.41-46
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• 2002

A numerical simulation was made to determine the motion of particles in the fluid. The simulation is based on the Eulerian-Lagrangian method. The fluid motion was solved using a PISO-based finite-element method and a $\kappa-\epsilon$ model of turbulence. In the Lagrangian method for the solid phase, the trajectories of particles are calculated by integrating the equations of motion of a single Particle, and the collision between particles are taken into account. The influence of particles on the fluid phase is taken into account by introducing source terms in the Eulerian equations govering the fluid flow. It is known as the particle-source-in-cell (PSIC) method. Also, the turbulent effect in the particles and fluid notion is considered. The numerical results were compared with the experiment for a two-phase flow in a vertical pipe.