• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.343-348
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• 2007

Molecular dynamics study of thermal NIL (Nano Imprint Lithography) process is performed to examine stamp-resist interactions. A layered structure consists of Ni stamp, poly-(methylmethacrylate) thin film resist and Si substrate was constructed for isothermal ensemble simulations. Imposing confined periodicity to the layered unit-cell, sequential movement of stamp followed by NVT simulation was implemented in accordance with the real NIL process. Both vdW and electrostatic potentials were considered in all non-bond interactions and resultant interaction energy between stamp and PMMA resist was monitored during stamping and releasing procedures. As a result, the stamp-resist interaction energy shows repulsive and adhesive characteristics in indentation and release respectively and irregular atomic concentration near the patterned layer were observed. Also, the spring back and rearrangement of PMMA molecules were analyzed in releasing process.

• 한국세라믹학회지
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• 제48권2호
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• pp.195-199
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• 2011

The effect of copper oxide on migration and interaction of protons in barium zirconate was investigated using density functional theory. One copper atom was substituted for a zirconium atom site, and a proton was added to a $3{\times}3{\times}3$ barium zirconate superstructure. An energy barrier of 0.89 eV for proton migration was the highest among several energy barriers. To investigate the interaction between multiple protons and a copper atom, two protons were added to the superstructure. Various proton positions were determined by the interaction between the two protons and the copper atom.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2004년도 학술대회지
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• pp.139-142
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• 2004

The object of the present work is the acoustic emission energy analysis of subambient pressure tri-pad slider. Head/disk interaction during start/stop and constant speed were detected by using acoustic emission (AE) test system The frequency spectrum analysis is performed using the AE signal obtained during the head/disk interaction Natural frequency analysis was performed using Ansys program. Acoustic emission energy was calculated for the slider modes.

• 약학회지
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• 제39권1호
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• pp.78-84
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• 1995

Based on Computer graphics molecular modeling method, quinolone derivatives as DNA-gyrase inhibitors formed stable DNA-intercalation complex with deoxycytidilyl-3',5'-deoxy guanosine[d($C_{p}G)_{2}$] dinucleotide. When d($C_{p}G)_{2}$ and d($A_{p}T)_{2}$, were compared in order to find out which DNA could form more stable DNA-Drug complex based on interaction energy($\Delta$E) and DNA-Drug complex energy, d($C_{p}G)_{2}$ resulted in lower energy than d($A_{p}T)_{2}$.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.630-634
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• 1995

The cluster distributions for different concentrations of 1,4-dibromonaphthalene (DBN) in 4,4'-dibromobenzophenone (DBBP)/1,4-dibromonaphthalene (DBN) choleic acid were determined by a computer simulation in order to model the energy transfer dynamics. The results of the simulation indicate that long range interaction between molecules further apart than nearest does not occur and energy transfer efficiency is restricted by single range interaction. The results also demonstrate that the trapping is diffusion limited. The energy transfer rate is reduced by a factor of 15 in DBBP/DBN choleic acid realtive to that in DBBP/DBN doped into polystyrene due to the larger distance between molecules.

• Current Optics and Photonics
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• 제1권3호
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• pp.203-206
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• 2017

We report a passive Q-switching of an all-fiber erbium-doped fiber laser delivering high pulse energy by using a high quality single-walled carbon nanotube saturable absorber (SWCNT-SA). A side-polished fiber coated with the SWCNT is employed as an in-line SA for evanescent wave interaction between the incident light and the SWCNT. This lateral interaction scheme enables a stable Q-switched fiber laser that generates high pulse energy. The central wavelength of the Q-switched pulse laser was measured as 1560 nm. A repetition rate frequency of the Q-switched laser is controlled from 78 kHz to 190 kHz by adjusting the applied pump power from 124 mW to 790 mW. The variation of pulse energy from 51 nJ to 270 nJ is also observed as increasing the pump power. The pulse energy of 270 nJ achieved at maximum pump power is 3 times larger than those reported in Q-switched all-fiber lasers using a SWCNT-SA. The tunable behaviors in pulse duration, pulse repetition rate, and pulse energy as a function of pump power are reported, and are well matched with theoretical expectation.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.220-220
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• 2015

Water, energy, and food security already became a risk that threatens people around the world. Increasing of resources demand, rapid urbanization, decreasing of natural resources and climate change are four major problems inducing resources' scarcity. Indeed, water, energy, and food are interconnected each other thus cannot be analyzed separately. That is, for simple example, energy needs water as source for hydropower plant, water needs energy for distribution, and food needs water and energy for production, which is defined as W-E-F nexus. Due to their complicated linkage, it needs a computer model to simulate and analyze the nexus. Development of a computer simulation model using system dynamics approach makes this linkage possible to be visualized and quantified. System dynamics can be defined as an approach to learn the feedback connections of all elements in a complex system, which mean, every element's interaction is simulated simultaneously. Present W-E-F nexus models do not calculate and simulate the element's interaction simultaneously. Existing models only calculate the amount of water and energy resources that needed to provide food, water, or energy without any interaction from the product to resources. The new proposed model tries to cope these lacks by adding the interactions, climate change effect, and government policy to optimize the best options to maintain the resources sustainability. On this first phase of development, the model is developed only to learn and analyze the interaction between elements based on scenario of fulfilling the increasing of resources demand, due to population growth. The model is developed using the Vensim, well-known system dynamics model software. The results are amount of total water, energy, and food demand and production for a certain time period and it is evaluated to determine the sustainability of resources.

• 로봇학회논문지
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• 제1권2호
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• pp.135-141
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• 2006

This paper presents offline estimation of equivalent physical damping parameter in haptic interaction systems where damping is the most important parameter for stability. Based on the previous energy bounding algorithm, an offline procedure is developed in order to estimate the physical damping parameter of a haptic device by measuring energy flow-in to the haptic device. The proposed method does not use force/torque sensor at the handgrip. Numerical simulation and experiments verified effectiveness of the proposed method.

• 한국융합학회논문지
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• 제11권6호
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• pp.15-21
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• 2020

전자상거래 생방송은 최근 몇 년 동안 중국에서 점차 유행하고 있는 새로운 온라인 쇼핑 방식이다. 생방송 기술에 의해 탄생한 전자상거래 생방송에서 수많은 사람들이 생방송을 보고 온라인 인터랙티브에 참여함으로써 구매 집단으로 응집되어 인터랙티브에서 안정적인 감정 에너지를 얻게 된다. 미시적 사회학적 시각에 기초하여 정서적 에너지 개념을 결합하고 인터랙티브 의식 체인 모델에 의해 전자상거래 생방송의 의식 구성요소를 볼 수 있으며, 어떻게 개인이 사회적 인터랙티브에서 구매 집단으로 뭉칠 수 있는지를 보여줄 수 있다. 인터랙티브 의식 이론에 대해 학계는 심도 있는 탐구를 하여 인터랙티브 의식 이론을 현실에 적용하려 하였다. 하지만 전자상거래 생방송의 인터렉티브 의식 이론에 대한 해석이 아직 문헌자료가 되지 않았는데, 저는 생방송 상황 중의 인터랙티브를 연구 대상으로 하고 인터랙티브 의식 이론으로 이 현상을 관찰한 다음에 전자 상거래 생방송 그룹의 인터렉티브 의식 체인 모델을 제시한다.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.2068-2071
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• 2009

This paper presents a multiple degree-of-freedom (dof) energy bounding approach (EBA) to enhance directional transparency while guaranteeing stability for multiple-dof haptic interaction. It was observed that the passivity condition for multiple ports may lead to some oscillatory limit cycle behaviors in some coordinate directions even though the total sum of energy flow-in is positive, meaning that the system is passive. The passivity condition, therefore, needs to be applied to each coordinate in order to avoid oscillatory behavior by keeping each energy flow-in always positive. For guaranteeing passivity, which in turn, stability in each coordinates, the EBA is applied. For multiple-dof haptic interaction, however, the EBA in each coordinate may distort the direction of the force vector to be rendered since the EBA may cut down the magnitude of the force and torque vectors to be rendered in order to ensure the passivity. For avoiding this problem, a simple projection method is presented. The validity of the proposed algorithm is shown by several experiments.