• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.78-80
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• 2005

Haptic interface apparatus is the device which can offer users virtual reality not only by visualization of virtual space but also by force or tactile feedback. In this paper, we designed and fabricated a 2D haptic interface device that can be used for various purposes, and implemented a virtual air-hockey system that users can easily find in game rooms. By suitable modeling and haptic rendering, users can feel the impact and the reaction force with his/her hand holding the handle through 2D haptic interface device when he/she hit an air-hockey puck with the handle. Through the trial demonstration. we observed the reasonable effect of direction and speed of a ball like doing in reality.

• 디자인학연구
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• 제17권2호
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• pp.5-14
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• 2004

기술의 발전과 HCI에 대한 연구 등으로 예전에는 생각할 수 없을 만큼 컴퓨터는 손쉽게 접근할 수 있게 되었고, 이러한 변화는 컴퓨팅을 우리가 살고 있는 실세계로 옮겨오게 되었으며, 실체적 인터페이스에 대한 관심이 높아지고 있다. 실체적 사용자 인터페이스(TUI)는 빛, 소리, 공기 및 물의 흐름과 같은 것을 미디어로 이용하여 인간 지각의 주변에 있는 물체를 사용자가 인지할 수 있게끔 한다. 실체적 사용자 인터페이스 시스템은 디지털 비트에 구현된 실체화된 물리적 물체이며, 이것은 물론 만져지는 인터페이스(Graspable UI)의 특징을 가지고 있다. 그리고 다양한 물리적 물체를 입력에 사용하고 있다. 그러나 여기서 실체적 인터페이스의 핵심을 이루는 텐저블즈는 단순한 입력 장치만이 아니라 시스템의 모델을 구체적으로 형상화하는 전체 시스템을 의미한다. 텐저블즈의 물리적형상은 단순히 손으로 잡기 위한 실체가 아니라 시스템의 개념적 모델을 형상화한 실체이다. 사용자는 시스템의 물리적 형태를 통하여 시스템을 이용하고 이를 통하여 입력을 위한 액션을 취한다. 이러한 사용자의 액션에 대한 반응에 대해 시스템은 리액션을 취하게 되는데 사용자는 디지털적인 반응(사운드, 그래픽 정보)뿐만 아니라 텐저블즈의 형태, 위치 등의 물리적 속성 역시 리액션(Reaction)으로 받아들이게 된다. 본 연구는 텐저블즈의 물리적 형상과 물리적 속성 등, 인터랙션 과정에 영향을 미치게 되는 요소와 사용자 반응과 시스템의 리액션에 대한 연구를 다루고 있다.

• 한국표면공학회지
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• 제32권3호
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• pp.303-306
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• 1999

On the effect of substrate bias at first stage of diamond synthesis at lower substrate temperature(approximately 673K) using microwave plasma CVD and effect of reaction gas system for the bias enhanced nucleation were studied. The reaction gas was mixture of methane and hydrogen or carbon monoxide and hydrogen. The nucleation density of applied bias -150V using $CH_4-H_2$ reaction gas system, significantly higher than that of $C-H_2$ reaction gas system. When the $CH_4-H_2$ reaction was used, nucleation density was increased because of existence of SiC as a interface for diamond nucleation. By use of this negative bias effect for fabrication of CVD diamond film using two-step diamond growth without pre-treatment, fabrication of the diamond film consist of diamond grains $0.2\mu\textrm{m}$ in diameter was demonstrated

• Nuclear Engineering and Technology
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• 제53권3호
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• pp.833-841
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• 2021

During the postulated severe accident of nuclear reactor, eutectic reaction leads to low-temperature melting of fuel cladding and early failure of core structure. In order to model eutectic melting with the moving particle semi-implicit (MPS) method, the eutectic reaction model is developed to simulate the eutectic reaction phenomenon. The coupling of mass diffusion and phase diagram is applied to calculate the eutectic reaction with the uniform temperature. A heat transfer formula is proposed based on the phase diagram to handle the heat release or absorption during the process of eutectic reaction, and it can combine with mass diffusion and phase diagram to describe the eutectic reaction with temperature variation. The heat transfer formula is verified by the one-dimensional melting simulations and the predicted interface position agrees well with the theoretical solution. In order to verify the eutectic reaction models, the eutectic reaction of uranium and iron in two semi-infinite domains is simulated, and the profile of solid thickness decrease over time follows the parabolic law. The modified MPS method is applied to calculate Transient Reactor Test Facility (TREAT) experiment, the penetration rate in the simulations are agreeable with the experiment results. In addition, a hypothetical case based on the TREAT experiment is also conducted to validate the eutectic reaction with temperature variation, the results present continuity with the simulations of TREAT experiment. Thus the improved method is proved to be capable of simulating the eutectic reaction in the severe accident.

• 한국재료학회지
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• 제2권4호
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• pp.241-247
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• 1992

본 연구에서는 $Cu-Cu_2$O의 공정반응에 의한 구리와 알루미나의 직접접합에 대하여 연구 하였다. $1.5{\times}10^{-1}$torr, $1015^{\circ}C$에서 산화시킨 후 $10_{-3}$torr, 107$5^{\circ}C$에서 접합시킨 시편의 접합력과 계면특성을 인장시험, SEM, EDS 및 XRD를 통하여 분석하였다. 3분 산화시켜 접합하면 우수한 접합강도를 보이며 산화시간이 이보다 짧거나 길면 결합력은 저하하였다. 과단은 알루미나 공정조직 계면에서 발생하였으며 파단후 $Al_2O_3$표면에는 Cu쪽에서 빠져나간 $Cu_2$O nodule의 존재하였는 바 접합력은 $Cu_2$O-A$l_2O_3$계면보다는 $Cu-Cu_2$O계면에 좌우됨을 보여주고 있다. 접합력은 접합시간에 따라 완만한 증가를 보였으며 CuA$l_2O_4$및 $CuAlO_2$의 반응생성물이 접합중 형성되었다.

• 항공우주시스템공학회지
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• 제1권2호
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• pp.37-42
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• 2007

This paper proposes a numerical modeling approach to simulate the hybrid combustion phenomena. From the physical understandings of hybrid combustion, the computational domain was separated into three regions: the solid fuel, gas phase reactive flow, and the interface between solid and fluid. Moreover, for the accurate calculation, computational grids for these regions was generated at every time step considering the instantaneous moving interface which are governed by the balance equations using thermal pyrolysis. In the domain of reactive flow, by virtue of diffusion flame structure, turbulent combustion modeling was introduced using either mixture fraction approach or mean reaction rate approach.

• 한국진공학회지
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• 제18권3호
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• pp.151-163
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• 2009

유체 모델을 기반으로 하는 국내의 유도 결합 플라즈마원의 시뮬레이터 개발 현황을 정리하였다. 전체 시뮬레이터를 구성하는 각 부분으로서, 전자 가열, 하전 입자 및 중성종 수송, sheath를 포함한 표면 반응, 그리고 GUI (Graphic User Interface) 및 전후처리기 등의 순으로 설명되었다. 현재까지 시뮬레이터에 구현된 화학 반응 데이터와 swarm 데이터도 정리하여 보았고, 앞으로의 개발 방향을 전망하여 보았다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1997년도 제25회 춘계학술대회
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• pp.33-40
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• 1997

This study was undertaken to investigate tribology characteristics of the alumina ceramics($Al_2O_3$) for the vauiation of ambient condition such as air and distilled water. The results obtained were as follows. As the sliding speed increases, the friction coefficient in the air decreased due to the reduction of sheafing stress caused by the heat accumulation of contact interface. And the friction coefficient in the distilled water decreased due to an activation of the tribochemical reaction. As the contact load increases, the friction coefficient is small in the air due to temperature rise of the contact interface. However, at the low speed side in the distilled water, the friction coefficient holds a large value due to decrease of the tribochemical reaction. The friction surface of ceramics can be protected in the air by the influence of the oxides tansfered from STB2 and also in the distilled water by the influence of the corrosive productive hydroxides.

• 한국세라믹학회지
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• 제33권6호
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• pp.718-724
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• 1996

Deformation mechanism map of Langdon-Mohammed type for YBa2Cu3O7-x superconducting ceramic was constructed by considering mechanisms of Nabarro-Herring Coble and powder-law creep and grain boundary sliding (GBS) with an accommodation by grain boundary diffusion. The map was found consistent with experi-mental results not only of the creep the also of the superplastic deformation. It showed the transition from interface reaction-controlled to the grain boundary diffusion-controlled GBS mechanism at about 1 ${\mu}{\textrm}{m}$ grain size and 100 MPa flow stress in agreement with the experimental results.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2017년도 춘계학술대회 논문집
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• pp.118.2-118.2
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• 2017

Combustion behavior of Fe, CuO, NiO, ZnO and $Fe_2O_3$ powder mixture was carried out by finite element method (FEM) to understand a reaction at iron and metal oxide interface. The FEM was done by using ANSYS Fluent 17.0. Initial and boundary conditions are 1 atmosphere, room temperature, 0.1MPa of oxygen partial pressure, $T_{S1}=1127^{\circ}C$, $T_{S2}=327^{\circ}C$ for a cylindrical shape specimen with dia. $35{\times}80$ [mm]. The maximum combustion temperature is $1537^{\circ}C$ for the condition of conduction, convection and radiation. The combustion temperature and rate are about $847^{\circ}C$ and 3.9mm/sec, respectively. The combustion wave is enough to make ternary ferrite phase like $CuNiZnFe_2O_3$.