• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.12
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• pp.1179-1183
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• 2007

Electro-Active paper(EAPap) is a new smart material that has a potential to be used in biomimetic actuator and sensor. It is made by cellulose that is abundant material in nature. EAPap is fascinating with its biodegradability, lightweight, large displacement, high mechanical strength and low actuation voltage. Actuating mechanism of EAPap is known to be the combined effects of ion migration and piezoelectricity. However, the electromechanical actuation mechanisms are not yet to be established. This paper presents the modeling of the actuation behavior of water infused cellulose samples and their composite dielectric constants calculated by Maxwell-Wagner theory. Electro-mechanical forces were calculated using Maxwell stress tensor method. Bending deflection was evaluated from simple beam model and compared with experimental observation, and which result in good correlation with each other.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.144-151
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• 2011

Recent years have witnessed speed up of moving vehicles such as high-speed of trains. Increase in speed entails concomitant increase in turbulent air flow which contributes toward aerodynamic noise. The proposed method for aerodynamic noise reduction is based on a biomimetic design of owl feather. The five morphological parameters of the owl feather is extracted from close observation, and simulation cases are constructed by applying design of experiments methodology. Swirling strength for each case is obtained through steady-state CFD analysis, and key morphological parameters that affect the turbulence are identified. Large eddy simulations (LES) are then performed on selected cases to predict the air turbulence. Different cases show varying vorticity distribution levels which is expected to lead to varying aerodynamic noise levels.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.9 s.252
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• pp.866-872
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• 2006

A numerical study on the propulsive characteristics of a biomimetic foil is done by developing an unsteady linearly-varying strength vortex method. A biomimetic foil is represented as a deforming foil with a tail fin. Present method is verified by comparing the simulated results with results using finite element and finite volume methods. A new boundary condition is imposed by considering the relative rotational velocity, which has not been included in the previous published literature. It is found that the undulation amplitude increases the thrust while maximum thickness is stepping down the thrust. It is also shown that there exists an optimal frequency for maximum thrust generation. It is believed that present results can be used in the investigation of the propulsive characteristics of the biomimetic deforming foil.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1029-1032
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• 2002

This paper describes a design of a tactile sensor, which can measure three components force and temperature due to thermal conductive. The bio-mimetic tactile sensor, alternative to human's finger, is comprised of four micro force sensors and four thermal sensors, and its size being 10mm$\times$10mm. Each micro force sensor has a square membrane, and its force range is 0.1N - 5N in the three-axis directions. On the other hand, the thermal sensor for temperature measurement has a heater and four temperature sensor elements. The thermal sensor is designed to keep the temperature. $36.5^{\circ}C$, constant, like human skin, and measure the temperature $0^{\circ}C$ to $50^{\circ}C$. The MEMS technology is applied to fabricate the sensing element of the tactile sensor.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.6
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• pp.1483-1492
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• 2016

Ducky USB is one of rarely-known keyboard-emulating BadUSBs. The attacking strategy using Ducky USB is taking and executing the scripted keystroke automatically whenever the USB is inserted into PC. Prior works exhibit some problems such as performance loss and additional device requirement. To solve this problem, this paper devised a countermeasure program to efficiently block the Duck USB in Windows. The experiment proves its effectiveness.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.202-205
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• 2005

The effects of ligands on reactivity under GoAgg oxidation system have been studied. Picolinic acid containing carboxylic acid showed the most excellent activity among various ligands. Also, Picolinic acid of ortho position carboxylic group in pyridine ring largely increased reaction rates in the GoAgg oxidation systems. From these results, we proposed the new mechanism on the GoAgg oxidation using ligands having carboxylic group at ortho position.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.272-272
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• 2017

베트남은 풍부한 노동력을 바탕으로 빠르게 경제가 성장하고 있다. 국내 물류기업은 해외시장 진출을 위해 노력하고 있다. 해외 물류기업도 베트남 시장에 진출하면서 물류 네트워크를 확대해 나가고 있다. 이러한 상황에서 국내 물류기업들도 기회를 포착하여 베트남 시장에 진출할 필요성을 실감하고 있다. 본 논문에서는 모방전략을 이용하여 국내 중견중소 물류기업의 베트남 물류시장 진출 전략 수립에 목적을 두고 있다.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.5
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• pp.521-528
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• 2009

In these days, biomimetic apprioach in the design and control of robotic system has drawn much attention. The human-being and mammals possess their own feet. Using the mobility of their feet, they are able to walk in various environments such as plain land, desert, swamp, and so on. Previously developed biped robots and four-legged robots did not employ such adaptable foot. In this work, a biomimetic foot mechanism is investigated through analysis of the foot structure of the human-being. This foot mechanism consists of a toe, an ankle, a heel, and some springs replacing the foot muscles and tendons. Using five toes and springs, this foot can adapt to various environments. A mathematical modeling for this foot mechanism was performed and its characteristics were observed through numerical simulation.

• Annual Conference on Human and Language Technology
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• 2016.10a
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• pp.176-180
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• 2016

대화형 시스템이 사람의 경청 기술을 모방할 수 있다면 대화 상대방과 더 효과적으로 상호작용 할 수 있을 것이다. 본 논문에서는 시스템이 경청 기술을 모방할 수 있도록 사용자의 발화를 기반으로 질문을 생성하는 것에 대해 연구하였다. 그리고 이러한 연구를 위해 필요한 데이터를 Image captioning과 Visual QA 데이터를 기반으로 생성하고 활용하는 방안에 대해 제안한다. 또한 이러한 데이터를 Attention 메커니즘을 적용한 Sequence to sequence 모델에 적용하여 질문을 생성하고, 생성된 질문의 질문 유형을 분석하였다. 마지막으로 사람이 작성한 질문과 모델의 질문 생성 결과 비교를 BLEU 점수를 이용하여 수행하였다.

• Journal of Adhesion and Interface
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• v.19 no.3
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• pp.123-128
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• 2018

As a mussel-inspired surface independent modification chemistry using catecholamine family molecule was suggested on 2007, there are tremendous efforts being done by researchers from around the world to adjust and develop diverse applications using catecholamine family. Accordingly, we will discuss about the novel method to extend catecholamine applications, which is through the functional group substitution of catecholamine molecules.