• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2017년도 추계학술대회
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• pp.19-21
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• 2017

Ship maneuvering performance is usually estimated in calm water conditions which provide valuable information about the ship maneuvering characteristics at the early design stage. However, the course-keeping ability and the maneuvering performance of a ship can be significantly affected by the presence of waves when ship maneuvers in real sea condition. Therefore, it is necessary to understand the maneuvering behavior of a ship in waves in the viewpoint of ship safety in the design stage. In this study, the force and yaw moment acting on a moving ship in regular waves with different wave length and wave direction will be performed in the square wave tank in Changwon National University. The results of this study can be used to help a person to design a ship hull with the best ship maneuverability in waves and disseminate knowledge on predicting ship maneuvering in regular waves in various wave directions.

• 센서학회지
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• 제21권3호
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• pp.192-197
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• 2012

This paper describes the control of the hand fixing system attached to the finger rehabilitation robot for the rehabilitation exercise of patient's fingers. The finger rehabilitation robot is used to exercise the finger rehabilitation, and a patient's hand is safely fixed using the hand fixing system. In this paper, the hand fixing system was controlled with PD gains to fix a palm of the hand, and the characteristic test for the hand fixing system was carried out to sense the fixed hand movement of the front and the rear, that of the left and the right, and that of the upper. It is thought that the hand fixing system could safely fix the hand, and the movement of the fixed hand could be perceived using the five-axis force/moment sensor attached to the hand fixing system.

• 자동차안전학회지
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• 제5권2호
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• pp.32-38
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• 2013

This paper presents collision avoidance using model predictive control algorithm. A model predictive control algorithm determines lateral tire force and yaw moment and steering angle input and differential braking input is determined from lateral tire force and yaw moment. A constraint for model predictive control is designed for obstacle avoidance. A objective function is designed to minimize lateral tire force and yaw moment input and to follow changed lane after collision avoidance. The performance of proposed algorithm has been investigated via computer simulation conducted to vehicle dynamic software CARSIM and Matlab/Simulink.

• 한국소음진동공학회논문집
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• 제14권1호
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• pp.24-31
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• 2004

Recently, as the marine compressor power is increased, vibration problems on the marine vessel with V/W type reciprocating compressor have been occurred. A research on the balancing of marine V/W type reciprocating compressor has hardly been reported though a number of researches on the balancing of rotating machinery have been conducted. As a V/W type compressor has high capacity with long stroke, compact size and high center of gravity, It is easy to have a vibration problem by a little bit unbalanced force and moment. In this study, calculation methods for balance weight of the V/W type reciprocating compressors, which have different piston weight and asymmetry structure, are formulated. And their reliability were verified by comparing calculated balance weight with the experimental results of the real marine V/W type reciprocating compressors.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2002년도 봄 학술발표회 논문집
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• pp.99-106
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• 2002

This paper presents an analytical investigation on the behavior of simple span integral abutment bridge. An integral abutment bridge is a simple span or multiple span continuous deck type bridge having the deck integral with the abutment wall. Although the temperature variation and earth pressure are the major attributor to the total stress in integral abutment bridge, the superstructure has been designed by modeling it as a simple or continuous beam In order to investigate the effect of temperature change and earth pressure on the superstructure of integral bridge, the simple span integral bridge is modeled as a plane frame element. Performing frame analysis, the variations of bending moment and axial force of superstructure due to the various loading combination are investigated with respect to the flexural rigidity of piles, and the bending moment and axial force obtained by frame analysis are compared with the maximum bending moment obtained by conventional design method and initial prestressing force respectively.

• 대한조선학회논문집
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• 제49권4호
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• pp.327-332
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• 2012

International Towing Tank Conference (ITTC) recommended verifying a ship's ability to move transversely at zero forward speed without altering heading by a crabbing test. In sea trial, all available propellers/rudders/thrusters should be used to find the maximum possible transverse speed. For estimating crabbing ability in the design stage, tests to estimate possible swaying force and yawing moment range using all available propellers/rudders/thrusters are conducted. By butterfly diagram, which compares possible swaying force and yawing moment range with external swaying force and yawing moment by wind, a ship's crabbing ability can be estimated. In this study, model tests of a cruise vessel equipped with bow thrusters and POD system were conducted to find out her crabbing ability in the design stage. To mimic quay condition, a model quay-wall was set in the towing tank.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.119-122
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• 2001

This paper discusses the peg-in-hole task of chamferless parts using force/moment/vision sensors. The directional error occurring during the task are categorized into two cases according to the degree of initial errors, And different Mechanical analysis has been accomplished for each cases. This paper proposes an algorithm which enables to reduce intial directional error using digital Images acquired from hand-eyed vision sensor, And to continue the task even with the large directional error by adjusting the error using digital image processing. The effectiveness of the algorithm has been demonstrated through experimentation using 5-axis robot equipped with a developed controller force/moment sensor and color digital camera on its hand.

• Steel and Composite Structures
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• 제46권6호
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• pp.773-791
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• 2023

Connections with damage concentrated to pre-selected components can enhance seismic resilience for moment resisting frames. These pre-selected components always yield early to dissipate energy, and their energy dissipation mechanisms vary from one to another, depending on their position in the connection, geometry configuration details, and mechanical characteristics. This paper presents behaviour insights on two types of beam-to-beam connections that the angles were designed as energy dissipation components, through the results of experimental study and finite element analysis. Firstly, an experimental programme was reviewed, and key responses concerning the working mechanism of the connections were presented, including strain distribution at the critical section, section force responses of essential components, and initial stiffness of test specimens. Subsequently, finite element models of three specimens were established to further interpret their behaviour and response that were not observable in the tests. The moment and shear force transfer paths of the composite connections were clarified through the test results and finite element analysis. It was observed that the bending moment is mainly resisted by axial forces from the components, and the dominant axial force is from the bottom angles; the shear force at the critical section is primarily taken by the slab and the components near the top flange. Lastly, based on the insights on the load transfer path of the composite connections, preliminary design recommendations are proposed. In particular, a resistance requirement, quantified by a moment capacity ratio, was placed on the connections. Design models and equations were also developed for predicting the yield moment resistance and the shear resistance of the connections. A flexible beam model was proposed to quantify the shear resistance of essential components.

• 한국항공우주학회지
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• 제32권8호
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• pp.64-71
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• 2004

측 추력(Lateral Jet)을 이용하여 자세를 제어하는 미사일 주위의 초음속 유동장 해석을 위하여 삼차원 Navier-Stokes 코드 (AADL3D)를 개발하고, 이를 이용한 수치해석 연구를 수행하였다. 분출 제트 압력, 분출 마하수 등을 포함하는 제트의 유동특성이 미사일에 미치는 수직력 및 피칭모멘트에 대한 영향을 알아보기 위한 사례연구를 수행하였으며, 공력 해석 결과 제트의 분출 압력과 분출 마하수 변화에 따른 서로 다른 수직력과 모멘트 변화 양상 및 그 원인을 확인할 수 있었다. 또한 대부분의 수직력 손실과 피칭모멘트 발생은 노즐 후방의 저압영역에 의한 것이며, 동일한 제트 추력일지라도 분출 마하수가 큰 경우가 분출 압력이 큰 경우보다 모멘트 발생 최소화에 유리함을 확인하였다.

• 한국항공우주학회지
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• 제32권9호
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• pp.27-34
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• 2004

측 추력(Lateral Jet) 제어 시스템에 의해 자세제어를 하는 미사일 주위의 초음속 유동장 해석을 위하여 삼차원 Navier-Stokes 코드 (AADL3D)를 개발하고, 이를 이용한 수치해석 연구를 수행하였다. 미사일의 받음각, 제트 노즐의 위치, 그리고 제트의 분출 각 등의 Parameter가 미사일에 미치는 수직력 및 피칭모멘트에 대한 영향을 알아보기 위한 사례 연구를 수행하였다. 또한 미사일은 무게 중심을 기준으로 4개 영역으로 나뉘어 각 부분에서의 수직력과 모멘트에 대한 기여도를 비교하였다. 공력해석 결과, 각 Parameter 변화에 대한 서로 다른 수직력과 모멘트 변화양상 및 그 원인을 확인할 수 있었다. 또한 각 Parameter 의 적절한 조합에 의해 모멘트 발생을 최소화 할 수 있음을 보여 주었다.