• Proceedings of the Korean Information Science Society Conference
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• 2005.07a
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• pp.811-813
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• 2005

무인 자동차 시스템과 같은 실시간 제어 환경에서는 각종 센서의 상황에 대한 주기적인 폴링, 실시간 스케줄링, 병행 메소드의 지원 실시간 병행 접근 제어 등과 같은 환경이 요구된다. 본 논문에서는 micro 내장형 운영체제상의 실시간 객체 엔진으로 개발한 TMO-eCos를 기반으로, TMO를 이용한 무인 자동차 제어프레이워크와 이를 활용한 응용 모델에 대해 기술한다. TMO 모델을 이용한 무인 자동차 제어 프레임워크는 실시간 제어 시스템 개발을 위한 객체 기반의 규격적 환경을 제공하여, 최근 국내외적으로 많은 연구가 진행되고 있는 지능헝 실시간 로봇 제어소프트웨어의 기본 플랫폼으로 활용될 수 있을 것이다.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06b
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• pp.363-367
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• 2007

본 논문에서는 Micro 내장형 운영체제상의 실시간 객체 엔진으로 개발한 TMO-eCos를 기반으로 TMO를 이용한 이족로봇 제어 프레임워크와 이를 활용한 실제 사람의 동작과 유사하게 이족로봇을 제어할 수 있는 응용모델에 대해 기술한다. TMO 모델을 이용한 이족로봇 제어 프레임워크는 시스템 개발을 위한 객체 기반의 규격적 단층을 제공하여 모션캡춰장비의 시그널을 분석 처리할 수 있도록 설계 구현되었다.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06b
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• pp.372-376
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• 2007

분산처리 시스템은 네트워크로 연결된 프로세서들로 구성되며, 시스템 내의 각 프로세서는 고유한 클럭을 갖는다. 글로벌 시간 기준으로 볼 때 수행중인 프로세스가 유지하는 시간은 분산시스템 각각 차이가 있을 수 있으므로 일관성 있는 시간관리가 필요하다. 본 논문에서는 TMO-eCos를 기반으로 하는 분산 처리 시스템에서 각 분산 시스템간 발생할 수 있는 클럭의 불일치 문제를 해결하기 위한 클럭 동기화 기법에 관해 논한다. 점진적인 클럭 동기화 알고리즘을 구하기 위해 마스터 노드의 클럭을 글로벌 클럭으로 가정하고 슬레이브 노드들은 마스터 노드의 클럭으로 동기화하는 방법에 대하여 정의하였다. 정의한 알고리즘을 시현하기 위한 분산 노드 간 로봇 제어 프로그램을 소개 한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.556-557
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• 2005

The distribution facilities, such as suspension insulator, line post insulator, lightning arrester, COS, used for long periods in the industrial pollution area were investigated. The electrical test and the material analyses were performed on the polluted and non-polluted facilities. The low frequency dry flashover voltage of polluted suspension was decreased about 8% in comparison with non-polluted one. The polluted materials turned out with the iron which came from the foundries. The polluted materials turned out with the iron which came from the foundries. This conductive materials decreased the leakage distance, resulting in reducing of electrical properties.

• Communications of the Korean Mathematical Society
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• v.31 no.4
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• pp.667-682
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• 2016

In this article we show a recursive method to compute the coefficients of the minimal polynomial of cos($2{\pi}/n$) explicitly for $n{\geq}3$. The recursion is not on n but on the coefficient index. Namely, for a given n, we show how to compute ei of the minimal polynomial ${\sum_{i=0}^{d}}(-1)^ie_ix^{d-i}$ for $i{\geq}2$ with initial data $e_0=1$, $e_1={\mu}(n)/2$, where ${\mu}(n)$ is the $M{\ddot{o}}bius$ function.

• Bulletin of the Korean Chemical Society
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• v.17 no.5
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• pp.461-463
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• 1996

The laser-induced fluorescence excitation spectrum of 7-amino-4-(trifluoromethyl)coumarin in a supersonic jet has been recorded in the 340-352 nm region. The electronic band origin was observed at 28622.8 cm-1. Vibrational assignments for the three fundamental low-frequency modes and eight combination bands have been made for the S1 electronic excited state. The out-of-plane vibrations of this molecule have been characterized from the low-frequency assignments of the spectrum. The periodic potential energy function for the CF3 torsion, which satisfactorily fits the observed data, were also determined to be V(Φ)=95X(1-cos3Φ)-32X(1-cos6Φ) where Φ is the torsional angle. The relatively low torsional barrier of 99 cm-1 in S1 state could be explained by the small steric interactions between the functional groups attached to a bicyclic ring.

• Journal of the Chungcheong Mathematical Society
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• v.32 no.3
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• pp.349-363
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• 2019

Let ${\mathbb{H}}^5$ be the 5-dimensional Heisenberg group equipped with a left-invariant metric. In this paper we calculate the volumes of geodesic balls in ${\mathbb{H}}^5$. Let $B_e(R)$ be the geodesic ball with center e (the identity of ${\mathbb{H}}^5$) and radius R in ${\mathbb{H}}^5$. Then, the volume of $B_e(R)$ is given by $${\hfill{12}}Vol(B_e(R))\\{={\frac{4{\pi}^2}{6!}}{\left(p_1(R)+p_4(R){\sin}\;R+p_5(R){\cos}\;R+p_6(R){\displaystyle\smashmargin{2}{\int\nolimits_0}^R}{\frac{{\sin}\;t}{t}}dt\right.}\\{\left.{\hfill{65}}{+q_4(R){\sin}(2R)+q_5(R){\cos}(2R)+q_6(R){\displaystyle\smashmargin{2}{\int\nolimits_0}^{2R}}{\frac{{\sin}\;t}{t}}dt}\right)}$$ where $p_n$ and $q_n$ are polynomials with degree n.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.2
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• pp.183-193
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• 1995

Assuming that fishing nets are porous structures to suck water into their mouth and then filtrate water out of them, the flow resistance N of nets with wall area S under the velicity v was taken by $R=kSv^2$, and the coefficient k was derived as $$k=c\;Re^{-m}(\frac{S_n}{S_m})n(\frac{S_n}{S})$$ where $R_e$ is the Reynolds' number, $S_m$ the area of net mouth, $S_n$ the total area of net projected to the plane perpendicular to the water flow. Then, the propriety of the above equation and the values of c, m and n were investigated by the experimental results on plane nettings carried out hitherto. The value of c and m were fixed respectively by $240(kg\cdot sec^2/m^4)$ and 0.1 when the representative size on $R_e$ was taken by the ratio k of the volume of bars to the area of meshes, i. e., $$\lambda={\frac{\pi\;d^2}{21\;sin\;2\varphi}$$ where d is the diameter of bars, 21 the mesh size, and 2n the angle between two adjacent bars. The value of n was larger than 1.0 as 1.2 because the wakes occurring at the knots and bars increased the resistance by obstructing the filtration of water through the meshes. In case in which the influence of $R_e$ was negligible, the value of $cR_e\;^{-m}$ became a constant distinguished by the regions of the attack angle $ \theta$ of nettings to the water flow, i. e., 100$(kg\cdot sec^2/m^4)\;in\;45^{\circ}<\theta \leq90^{\circ}\;and\;100(S_m/S)^{0.6}\;(kg\cdot sec^2/m^4)\;in\;0^{\circ}<\theta \leq45^{\circ}$. Thus, the coefficient $k(kg\cdot sec^2/m^4)$ of plane nettings could be obtained by utilizing the above values with $S_m\;and\;S_n$ given respectively by $$S_m=S\;sin\theta$$ and $$S_n=\frac{d}{I}\;\cdot\;\frac{\sqrt{1-cos^2\varphi cos^2\theta}} {sin\varphi\;cos\varphi} \cdot S$$ But, on the occasion of $\theta=0^{\circ}$ k was decided by the roughness of netting surface and so expressed as $$k=9(\frac{d}{I\;cos\varphi})^{0.8}$$ In these results, however, the values of c and m were regarded to be not sufficiently exact because they were obtained from insufficient data and the actual nets had no use for k at $\theta=0^{\circ}$. Therefore, the exact expression of $k(kg\cdotsec^2/m^4)$, for actual nets could De made in the case of no influence of $R_e$ as follows; $$k=100(\frac{S_n}{S_m})^{1.2}\;(\frac{S_m}{S})\;.\;for\;45^{\circ}<\theta \leq90^{\circ}$$, $$k=100(\frac{S_n}{S_m})^{1.2}\;(\frac{S_m}{S})^{1.6}\;.\;for\;0^{\circ}<\theta \leq45^{\circ}$$

• NEWSLETTER 전기공업
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• no.91-7 s.20
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• pp.1-23
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• 1991

• NEWSLETTER 전기공업
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• no.92-24 s.67
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• pp.1-20
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• 1992