• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.482-485
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• 1993

This paper deals with structured singular value and mixed sensitivity problem for robust performance. We derive the sufficient condition that mixed sensitivity problem satisfies structured singular value in robust performance problem. And we show the bound of perturbation between structured singular value and norm of mixed sensitivity functions.

• 전기학회논문지
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• 제63권8호
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• pp.1075-1079
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• 2014

In this paper, we describe the analysis and the compensation method of the g-sensitivity error for MEMS vibratory gyroscopes. Usually, the g-sensitivity error has been ignored in the commercial MEMS gyroscope, but it deserves our attention to apply for the missile application as a tactical grade performance. Thus, it is necessary to compensate for the g-sensitivity error to reach a tactical grade performance. Generally, the g-sensitivity error seems intuitively to be a gyroscope bias error proportional to the linear acceleration. However, we assert that the g-sensitivity error mainly causes not a bias error but a scale-factor error. And we verify that the g-sensitivity scale-factor error occurs due to the non-linearity of parallel plate electrodes. Therefore, we propose the compensation method to remove the g-sensitivity scale-factor error. The experimental result showed that a proposed compensation method improved successfully the performance of the MEMS vibratory gyroscope.

• 오토저널
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• 제13권1호
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• pp.35-45
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• 1991

A linear quarter model of a vehicle suspension system is built and simulated. Especially the so-called sensitivity analysis is conducted in order to show its applicability to design problems, and sensitivity function is determined in the frequency domain. The change of frequency response function is predicted, which depends on the design parameter variation and the property is verified by computer simulation. Typical performance measures, namely, sprung mass acceleration, suspension deflection, and tire deflection are examined. The vehicle model is analyzed for ist performance sensitivity as a function of the system's feedback gains. The variable feedback gains are selected as the spring and damping coefficients. Frequency response, RMS response, and performance index of the performance evaluation variables are considered and three-dimensional and contour plots of response surfaces are formed to examine output sensitivity to suspension feedback. Performance trade-offs over the entire frequency spectrum are identified from the FRF, and that between ride quality and handling characteristics are examined from the RMS responses.

• 한국공작기계학회논문집
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• 제12권1호
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• pp.92-100
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• 2003

Using a quarter car model, an analytic method for performance estimation of a vehicle suspension system with respect to frequency response, RMS response and performance index is presented. From frequency response function, compromization of response performance to the whole frequency range is verified and from RMS response and performance index, sensitivity of ride md handling characteristics are examined. Using a full car model, sweet area(stable ride area) are determined and performance sensitivity is estimated according to the change of feedback gains. In order to esimate the output sensitivity, response we is displayed using a 3-dimensional contour plot. Design data n suggested for optimal design parameter esimation, which maximize the performance of the given suspension system.

• 대한기계학회논문집
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• 제14권6호
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• pp.1464-1473
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• 1990

Optimal design parameters are estimated from the sensitivity function and performance index variation. Suspension design modification for performance improvement and basic materials for practical applications are presented. The linear quarter model of a vehicle suspension is analyzed in order to represent the utilities of sensitivity analysis, and sensitivity function is determined in the frequency domain. The change of frequency response function is predicted, which depends on the design parameter variation and the property is verified by computer simulation. As an investigation results of sensitivity function for the vibrational amplitude of sprung mass to road profile input, it is shown that the most sensitive parameters are the suspension damping and the suspension stiffness. In order to identify the effects of these two parameters to the performance of suspension system, the performance index variation according to the changes of parameters is considered and then optimal design parameters are determined. It is verified that the system response is improved noticeably in the both of frequency and time domain after the design modification with the optimal parameters.

• 스트레스연구
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• 제27권2호
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• pp.199-204
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• 2019

본 연구는 불안민감도가 과제수행과 스트레스 반응에 미치는 영향을 살펴보고, 이 과정에 우울감은 어떠한 영향을 미치는지 확인하였다. 참가자들은 제한된 시간에 암산 문제를 완수하였고, 불안민감도지수와 우울증 선별도구에 응답하였다. 더불어, 실험 전후 참가자들의 코르티졸(Cortisol) 변화량을 확인하였다. 그 결과, 불안민감도가 높은 사람은 과제수행의 정확도가 떨어지고 코르티졸 수치가 유의미하게 상승하였다. 또한, 불안민감도와 우울감이 모두 높은 참가자들이 코르티졸 수치가 가장 크게 상승하였다. 본 연구는 자기보고식 응답에 근거하여 임상증상을 기술하는 것을 넘어 과제수행의 정확도와 생화학적 지표를 함께 제시함으로써, 보다 안정적으로 개인의 불안민감도와 우울감의 관계를 논의하였다는 의의를 지닌다.

• 한국보육지원학회지
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• 제6권2호
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• pp.39-56
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• 2010

본 연구의 목적은 보육직무능력 프로그램의 효과를 검증하는 것이다; 즉 보육시설에서 보육효능감, 교사역할수행, 교사민감성 향상을 위한 교육을 함으로써 보육효능감, 영아교사의 역할수행, 영아의 요구에 대한 교사민감성을 증진시키고자 하는 것이다. 본 연구대상은 정읍시의 44명의 영아담당 보육교사들이다. 이들은 통제집단 22명과 실험집단 22명의 교사로 나뉘어졌다. 교사들은 보육효능감, 교사역할수행, 교사 민감성을 평가하기 위해 사전-사후검사로서 질문지에 응답하였다. 본 연구결과, 보육직무능력 프로그램에 참여한 실험집단의 보육효능감, 교사역할수행, 교사민감성이 통제집단에 비해 유의하게 증진되었다. 결국, 보육효능감, 교사역할수행, 민감성을 향상시키기 위해 수행된 프로그램의 효과가 있음을 알 수 있었다.

• 대한건축학회논문집:구조계
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• 제36권5호
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• pp.177-185
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• 2020

The building energy performance indicator, called Energy Performance Index (EPI), has been used for the past decades in South Korea. It has a list of design variables assigned with weighting factors (a, b). Unfortunately, the current EPI method is not performance-based but very close to a prescriptive rating. With this in mind, this study aims to propose a new performance-based EPI method. For this purpose, a global sensitivity analysis method, Sobol, is employed. The Sobol method is suitable for complex nonlinear models and can decompose all the output variance due to every input. The Sobol sensitivity index of each variable is defined as 0 to 1 (0 to 100%), and the sum of all sensitivity indices is equal to 1 (100%). In this study, an office building was modeled using EnergyPlus and then the Latin Hypercube Sampling (LHS) was conducted to generate a surrogate model to EnergyPlus. The sensitivity index was suggested to replace weight (a) in the existing EPI. In addition, the discrete weight (b) in the existing EPI was replaced by a set of continuous regression functions. Due to the introduction of the sensitivity index and the continuous regression functions, the new proposed approach can provide far more accurate outcome than the existing EPI (R²: 0.83 vs. R²: 0.01 for cooling, R²: 0.66 vs. R²: 0.01 for total energy). The new proposed approach proves to be more rational, objective and performance-based than the existing EPI method.

• 전기학회논문지
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• 제63권10호
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• pp.1455-1460
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• 2014

Wind turbine generators were designed on general regulations of wind condition. At real situations, it could be different from the design conditions. There are many control methods and definitions of transient region, because an efficient wind turbine generator control logic is the important matter in generator performance and annual energy production at real conditions. In this document, the power generation sensitivity for wind speed and turbulence intensities was defined to know the sensitive transient region. Wind conditions are applied for the ranges of 7~10m/s mean wind speed and 14~20% turbulence intensity. The sensibility of HR-D86 wind generator was increased in transient region(8~10m/s) on power curve diagram through a torque control to a pitch control. And then GH-bladed simulations was performed for performance analysis of the torque mode switching in transient region on 2MW direct drive wind generator(HR-D86) which is designed IEC class II for onshore. Through the sensitivity and performance analysis, the sensitivity for real wind condition could be the performance index for an wind generator. And the torque mode switching in transient region can increase the mean power generation on HR-D86 wind turbine generator.

• 한국군사과학기술학회지
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• 제20권4호
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• pp.543-550
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• 2017

Various chemical properties including density and heat of formation of 1-substitued trinitroimidazoles (TNIs) were estimated by using density functional theory (DFT). Using chemical properties estimated by DFT, explosive performance and sensitivity of 1-substitued TNIs were analyzed by following the ADD Method-1 procedure. The results were displayed on two-dimensional performance-sensitivity plot, and were compared with those of explosive molecules commonly used in many military systems. Different 1-substituents of TNI made that both explosive performance and impact sensitivity were changed significantly. Methyl substituted TNI became moderately insensitive and slightly less powerful. Amino, fluoro, picryl, and difluoroamino substituted TNIs were highly powerful like RDX and HMX, but greatly sensitive. Nitro substituted TNI was predicted to be extremely sensitive to be handled as a secondary explosive.