• Tribology and Lubricants
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• 제23권2호
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• pp.61-65
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• 2007

It is very important to connect machinery and maintain it. This is usually done by bolt joint. There are two ways in connecting the bolt joint : the angle method and the torque method. The torque method is a method that let the clamping force maintain. The underhead of the bolt's head and the thread friction are the main influences. This study focuses on how the clamping farce and friction coefficient change under the condition in vibrating the underhead of the bolt's head part. As a result, under vibration condition, we found out that the clamping farce increases, while the friction coefficient decreases.

• Progress in Superconductivity
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• 제5권2호
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• pp.141-143
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• 2004

For designing a flywheel system using superconductor, it is necessary to understand the basic characteristics of the classical superconductor bearing. It is difficult to expect the characteristics of superconductor bearings using models that have been introduced up to now. In the "Frozen image" concept, the farce between the permanent magnet and the superconductor can be divided into two forces between permanent magnet and two imaginary magnets in the superconductor; one represents attraction farce and the other represents a repulsion force. We calculated the characteristics of two superconductor bearings, such as an axial, the radial stiffness and the levitation force. This calculation method was very helpful to expect the characteristics of the superconductor bearings. Using this model, we established the optimum condition for the superconductor bearing.r bearing.

• Journal of Welding and Joining
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• 제20권3호
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• pp.98-104
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• 2002

A study on microstructures of welds for Zircaloy-4 sheath end closure by the resistance upset welding methods was carried out. Two upset welding process variations such as magnetic farce and multi-impulse resistance welding were used. Grain size and microhardness across welds were analysed in terms of welding parameters. Magnetic farce resistance weld with one cycle of unbalanced mode has smaller upset length and $\alpha-grain$ size in heat affected zone than those of multi-impulse resistance weld because of lower heat input and shorter welding time. Heat affected zone formed by two upset resistance welding variations revealed fine Widmanstatten structure or martensitic ${\alpha}'$ structure due to the high heating rate and foster cooling rate. Magnetic force resistance welds showed recrystallized grains before grain growth, whereas multi-impulse resistance welds showed full grain growth.

• 제어로봇시스템학회논문지
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• 제12권11호
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• pp.1088-1094
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• 2006

In this paper, an auto path generation and an active compliance grinding control using 3-axis farce sensor are presented. These control algorithms enable the grinding robot to follow unknown path of various workpiece shape pattern. The robot is able to go grinding along unknown paths by position controller managing tangential direction angle and cutting speed, with only information about the start position and the end position. Magnitude and direction of normal force are calculated using force data that go through low pass filter. Moreover, normal and tangential directions are separated for force control and velocity control, respectively.

• 한국정밀공학회지
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• 제17권1호
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• pp.198-203
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• 2000

In this paper, a numerical analysis is carried out to show the effect of friction farce on the dynamic characteristics of a flow divider valve. The continuity equations and the equation of motion fur spool are numerically solved. The viscous friction force acting on the spool is considered analyzing the Reynolds equation which governs the viscous flow in the clearance gap between the spool and sleeve. Dynamic characteristics are highly affected by the viscous friction farce whose magnitude is relatively small compare with other fluid forces. Therefore present theoretical formulation and numerical scheme can be used generally in designing and performance evaluation of all the hydraulic spool valve.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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• pp.107-114
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• 2001

When group pile supporting structures are to be subjected to large lateral loads, generally, hatter piles are used in group pile with vertical piles. It is well known that batter piles resist lateral static loads which are acted upon the piles as axial farces quite well but, they show a poor performance under seismic loads. However, it is not yet known how the batter piles behave under dynamic loading and how to strengthen the batter piles to improve the seismic performance. Shaking table tests were performed to investigate the seismic behavior of the batter pile and to bring up the countermeasures to improve the seismic performance. As the result of the shaking table tests, batter piles failed due to not only the excessive increase of compressive force near the pile head but also that of tensile force. In case that the pile head was connected with pile cap by rubber joint, the max. acceleration at the pile cap was reduced due to the high damping ratio of rubber and the max. moment and max. axial farce at the pile head was decreased remarkably. When the inclinations(V:H) of the batter pile were 8:3 and 8:4, max. moment, max. shear force, and max. axial farce were reduced notably and max. acceleration and max. displacement at the pile cap was diminished, too.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.334-340
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• 2002

This paper proposes a new anti-slip re-adhesion control system fur electric railway vehicle driven by inverter-fed induction motors. This paper introduces an instantaneous tangential farce coefficient estimator between driving wheel and rail, which is based on disturbance observer. The torque command of proposed system regulates to exceed this estimated tangential farce coefficient in order to avoid undesirable slip phenomenon of driving wheels. We have already proposed the anti-slip re-adhesion control system based on disturbance observer for simplified one wheel equivalent model successfully. This paper extend to this system to the actual bogie system, which has four driving wheels driven by two induction motors fed by one inverter. In order to apply anti-slip re-adhesion control to the actual bogie system a new anti-slip re-adhesion control based on both disturbance observer and speed sensor-less vector control of induction motor with quick response are combined. The experimental results and the numerical simulation results prove the validity of the proposed control system.

• 한국엔터테인먼트산업학회논문지
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• 제15권4호
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• pp.89-100
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• 2021

희은 고대 그리스시대부터 현재까지 대중의 인기를 받으며 존재해왔다. 희극을 더 효과적으로 시각화하기 위해서는 배우의 연기가 중요한 요소로 작용한다. 그렇다면 배우가 희극적 연기를 수행하는데 있어서 실제로 어떻게 형상화할 수 있는지에 대한 적극적인 논의가 필요하다. 연극 <코트>의 김서영 역을 중심으로 희극적 연기 방법에 관해 접근하고자 한다. 본 연구자가 김서영 역을 맡아 수행하였으며, 희극적 연기의 특징으로는 과장과 반복, 빠른 템포, 변화 있는 어조, 과장된 신체 행위 등을 들 수 있다. 희극적 연기는 반응의 부조화에서 비롯된다. 자극에 대해 기대하지 않은 반응은 관객의 웃음을 유발할 수 있는 요인이 되기 때문이다. 또한 희극적 연기는 과장과 반복이 중요하게 작용하는데, 여기에는 진실한 연기가 기반이 되어야 한다. 행위의 빠른 템포감과 말의 변화 있는 어조도 희극적 연기 표현에 영향을 미치며, 소극(farce) 연기의 특징이라고 할 수 있는 '슬랩스틱'과 '군무' 등의 구현은 관객의 웃음을 유발하는 데 중요한 역할을 한다. 이러한 특징적 요소들이 희극적 효과를 나타내기 위해서는 진실하게 표현하는 배우의 연기가 기반이 되어야 한다. 희극적 연기에서 중요한 것은 텍스트의 서사적 흐름과 특징을 이해하고 그것을 정확하게 표현하는 것이다. 배우는 자신의 수단을 진실하게 표현하고 텍스트에서 요구하는 것을 있는 그대로 충실하게 보여준다면 희극적 효과는 충분히 나타낼 수 있다. 이러한 연구가 다양한 연기예술에 대한 탐구와 연기교육현장 그리고 연극창작 과정에 도움이 되길 기대한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.293-296
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• 2002

This work presents the reconstruction of impact force produced by the collision between two elastic structures. The 2-DOF impactor was designed. The shape control of impact farce using correlations of the dynamic characteristics and impact force history between two elastic structures is accomplished. The effects of the relative motion between impactor and elastic structure on the impact force shape are studied. Reconstruction characteristics of impact force in cantilever beam are reviewed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.69-71
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• 1994

In fabricating linear actuator using the GMA(Giant Magnetostrictive Alloy : Terfenol-D). the clamping unit is needed to accumlate each displacement from the GMA rod. Two types of the clamping unit (one is using piezoelectric device and the other electromagnetic farce) were made and tested. From the result of the experiment, we conclude that the electromagnetic clamping unit has advantages over the piezoelectric clamping unit.