• 제어로봇시스템학회논문지
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• 제18권12호
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• pp.1101-1105
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• 2012

This study proposes a method for improvement of PD type fuzzy controller. The method includes self tuner using gradient algorithm that is one of the optimization algorithms. The proposed controller improves simple Takagi-Sugeno type FLC (Fuzzy Logic Control) system. The simple Takagi-Sugeno type FLC system changes nonlinear characteristic to linear parameters of consequent membership function. The simple FLC system could control the system by calibrating parameter of consequent membership function that changes the system response. While the determination on parameter of the simple FLC system works well only partially, the proposed method is needed to determine parameters that work for overall response. The simple FLC system doesn't predict the response characteristics. While the simple FLC system works just like proportional part of PID, our system includes derivative part to predict the next response. The proposed controller is constructed with P part and D part FLC system that characteristic parameter on system response is changed by self tuner for effective response. Since the proposed controller doesn't include integral part, it can't eliminate steady state error. So we include a gain to eliminate the steady state error.

• 복식
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• 제60권5호
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• pp.117-127
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• 2010

In this study, hyperspace is a result of imagination created by means of facts and fiction, represents a transfer to determination and indetermination, and means an extension to an open form. In other words, hyperspace is a high dimensional space expanded to imagination through the combination of the viewpoint on facts in this dimension and fiction. When the 2D plane surface or 3D symmetry is destroyed, or when the frame is twisted or entangled, the non-Euclidean geometry is created eventually. And when the twisting leads to transmutation and the destruction of the form reaches the extreme; this in turn became the twisting like Mbius band. Likewise, the non-Euclidean geometry is co-related to the asymmetry of the Higgs mechanism. When the 'destruction of symmetry' is considered, symmetric theory and asymmetric world can be connected. The asymmetry in turn can maintain balance by arranging the uneven weights at different distances from the shaft. Moreover, at this the concept of the upper, lower, left and right, which was included in the original form, may be crumbled down. The destruction of the symmetry is essential in order to present forecast that coincides with the phenomenon of the real world. Non-Euclidean geometry characteristic is expressed by asymmetry, twists, and deconstruction and its representative characteristic is ambiguity. The boundary between the front, back, upper, lower, inner and outer is unclear, and it is difficult and vague to pinpoint specific location. The design that does not clearly define or determine the direction of wearing costume is indeed the non-oriented design that can be worn without getting restricted by specific direction such as front and back. Non-Euclidean geometry characteristic of hyperspace have been applied to create new shapes through the modification of the substance from traditional clothing of the eastern world to modern fashion. The way of thinking in the 'hyperspace' that used to be expressed in the costumes of the east and the west in the past became the forum for unlimited creation.

• Ecology and Resilient Infrastructure
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• 제1권1호
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• pp.29-38
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• 2014

본 연구는 식생호안의 안정성 평가에 중요한 인자인 식생 근모량에 따른 식생호안의 전단강도와 침식특성을 분석하였다. 식생호안의 평균근모량은 자체 제작한 채취기를 이용하여 측정하였다. 본 연구에서 사용된 식생은 식생호안에서 다소 우점종인 달뿌리풀이다. 흐름 특성별 실험결과 근모량이 증가함에 따라 토양의 전단강도가 증가함을 확인하였고, 아울러 근모량의 증가에 따라 침식율은 지수함수적으로 감소함을 확인하였다. 식생토양의 전단강도가 증가함에 따라 침식율이 지수함수적으로 감소되어 근모량에 기인한 전단강도의 증가는 침식 저항능력의 증가를 가져왔다. 아울러 근모량에 따른 전단강도와 침식율의 상관분을 실시하여 높은 상관계수를 가진 식을 제시하였다. 식생을 가진 호안의 수리적 안정성에는 근모량의 증가에 의한 전단강도와 유수의 특성인 Froude수에 지배적임을 확인하였다.

• 한국임상수의학회지
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• 제19권3호
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• pp.312-315
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• 2002

질병에 이환된 개체로부터 이환되지 않은 개체를 구분하기 위해 사용되는 대부분의 진단검사는 판별의 기준점 (cut-off value)을 필요로 한다. ROC (receiver operating characteristic) 곡선은 이러한 목적으로 흔히 사용되고 있으며 진단의 기준점을 다양하게 변화시킬 때 진단검사의 정확도 (민감도와 특이도)를 제시해주는 지표로 활용되고 있다. 저자들은 수의학관련 연구자들이 이 방법을 효과적으로 사용할 수 있도록 EXCEL에 내장된 비쥬얼 베이직으로 binormal ROC 곡선의 최대우도비를 계산해주는 프로그램을 작성하였다. 방사선 분야의 자료와 미생물학 자료를 예제로 들어 이 프로그램의 활용성을 높이고자 하였고 이 분야에 관심이 있는 연구자는 저자에게 연락하여 이 프로그램을 얻을 수 있다.

• 플랜트 저널
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• 제17권4호
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• pp.35-40
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• 2021

본 연구에서는 서인천복합 6호기 가스터빈 발전기계통에 대하여 기술특성시험을 실시하여 모델정수를 도출하고 검증하였다. 발전기 최대/최소 무효전력 한계시험 결과 최대 무효전력 한계는 80 MVar이고, 최소 무효전력 한계는 -30 MVar이다. 발전기는 GENROU 모델을 사용하였고, 계자시정수(T'do)는 4.077 s, 관성정수(H)는 5.461 P.U로 결정하였다. 여자시스템은 ESST4B 모델을 사용, 무부하 2% AVR 스텝시험을 모의하는 방식으로 모델정수를 도출하고 검증하였으며, PSS 모델링은 PSS2A 모델정수로 도출하였고, PSS Off/On일때 측정된 계측 데이터를 모의, 비교하여 검증하였다. 조속기-터빈는 GGOV1 모델을 사용하여 모델정수를 도출하고 검증하였다. PSS/E 시뮬레이션 프로그램을 통해 10% 조속기 스텝시험을 모의하여 결정된 조속기-터빈 모델정수의 수치 안정성을 확인하였다.

• Elastomers and Composites
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• 제58권4호
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• pp.179-190
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• 2023

The effect of the particle size and silica structure on the wear behavior of Silica/Styrene-Butadiene Rubber (SBR) compounds was investigated using a blade-type abrader and the findings were compared with those obtained with an Akron abrader. The compensated characteristic parameter (Ψ_c), which was the contributory factor of the combined effect of the particle size and filler structure, was introduced. This parameter was found to exhibit a linear relationship with the Young's modulus. The Young's modulus correlated more with Ψ_c than the uncompensated characteristic parameter (Ψ) modeled for carbon black. The wear rate and volume loss measured using a blade-type abrader and Akron abrader were respectively observed to be inversely proportional to Ψ_c, that is, the wear resistance of Silica/SBR compound improved as the particle size became smaller and the silica structure became intricate. The coefficient of determination (R²) obtained from the linear relationship between Ψ_c and wear rate was higher than those between Ψ_c and volume loss for the Silica/SBR compound. Thus, the blade-type abrader exhibited high potential to be used for accurately evaluating the effect of particle size and structural properties of silica on the wear behavior of SBR compounds.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.42-45
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• 2008

Recently, aluminum is widely used to reduce the vehicle weight. Aluminum curved extruded products are used for the design of automotive frame parts. This study focuses on the determination of process condition fur automotive bumper beam with various curvatures. In this study, a curvature prediction model has been proposed considering the geometric relationship and the characteristic of the curvature extrusion equipment. Using the proposed model and FE analysis, the appropriated process condition was determined to produce the bumper beam. Finally, curvature extrusion experiment was carried out to verify the effectiveness of the proposed curvature prediction model and the process condition.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1337-1340
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• 1995

For the purpose of rational design of air insulation, it is need to experiment with similar to real shape test object and conform the characterisics. But basic distances of air insulation of transmission line, tower, etc. can be acquired from flashover characteristic of rod-rod, rod-plane electrodes. In this paper, before field test of 765kV transmission line for determination of distances of phase to ground insulation, we execute lightning, switching impulse test with test electrod(rod-rod, rod-plane) against clearances of air insulation. Each tests use up-down method and consist of 30 times flashover test. Flashover data treatment program and air correction program following IEC 60-1(1987) standard were completely builted.

• Bulletin of the Korean Chemical Society
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• 제32권11호
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• pp.4016-4020
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• 2011

A number of mimetic peptides of apolipoprotein A-I, a major component for high density lipoproteins (HDL), were screened from the phase-displayed random peptide library by utilizing monoclonal antibodies (A12). A mimetic peptide for A12 epitope against apolipoprotein A-I was selected as FVLVRDTFPSSVCCP(pA2) exhibiting 45% homology with Apo A-I in the BLAST search. Solution structure determination of this mimotope was made by using 2D-NMR data and NMR-based distance geometry (DG)/molecular dynamic calculations. The resulting DG structures had low penalty value of 0.4-0.6 ${\AA}^2$ and the total RMSD of 0.7-1.7 ${\AA}$. The mimotope pA2 exhibited a characteristic ${\beta}$-turn conformation from Val[2] to Phe[8] near Pro[9] residue.

• 산업기술연구
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• 제22권A호
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• pp.219-228
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• 2002

The divided channel is not often used on the river and when the installation is for the controlling of the flow quantity. The determination of the channel size is not a easy task. Model tests are examined to confirm the variation of distribution rate by the method of the channel installation and the position of the structure and the adjustment of numerical simulation is executed by the comparing of the results. This study is to execute numerical model according to installation of divided channel by using AQUADYN program, the 2nd dimension numerical model, and HEC-RAS program, the 1st dimension numerical model, by the shape of divided channel. Also, it compares with difference by method about each case.