• 대한교통학회지
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• 제9권2호
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• pp.27-40
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• 1991

Delay is an widely-used tool for evaluating the operation of signalized intersections. This paper presents two mathematical models: a model converting stop delay into approach delay : and a model estimating delay at isolated signalized intersection. To develop the delay-conversion model, actual stop delay and approach delay experienced by individual vehicles were measured and then their relationship was formulated using ma-thematical procedure. the formula expressing the approach-delay to stop-delay ratio was a monotonously decreasing function of effective red time. New delay model was developed based on the following criteria; the fitness to measured delay for undersaturated traffic condition and the convergence to the deterministic overflow delay for oversaturated traffic condition. Performance of this model was better than those of other existing models based on the comparison study.

• 대한교통학회지
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• 제8권2호
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• pp.99-107
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• 1990

본 연구에서는 대형차의 승용차환산계수(PCE)를 결정하기 위해 혼합교통류의 흐름-저항의 관계를 나타내는 일반식을 확장하여 차두시간의 하여 항으로써 환산치를 산정하는 공식을 개발하였다. 여기서 차량배열 형태에 따른 각 경우 외 차두시간의 값은 수집된 교통자료의 희귀분석을 통해 추정토록 하였으며, 제시된 PCE치의 적절성을 검증하기 위해 거시적 접근방법에 의한 산정된 산치와 비교 분석토록 하였다.

• 물과 미래
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• 제13권1호
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• pp.39-48
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• 1980

우리나라 5대 하천유역 즉 한강, 낙동강, 금강, 영산강 및 섬진강에 대한 지역최대일 강우량의 실측기록을 써서 지역강우빈도 분석을 실시한바 분석방법으로는 다섯가지 방법을 활용하여 비교 검토하였다. 지역강우에 대한 빈도분석은 많이 이루어졌으나 지역강우에 대한 연구는 찾아 볼 수 없었기 때문에 이 성과를 쓴다면 홍수해석에 도움을 줄 수 있겠다 하겠다. 본 연구에서 제시한 강우량의 빈도별 산정식을 쓴다면 수문관측 기록이 나와 있지 않은 기타 지역에도 지역확률 강우량을 산정 할 수 있다.

• 한국치위생학회지
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• 제1권1호
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• pp.89-99
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• 2001

Estimating by clinical index the efficacy of three cases, where chewing gum is mixed with nanoparticle containing chlorhexidine, where chewing gum doesn't contain neither of them, and where with chlorhexidine only, this study has come to the following conclusion. 1. The chewing gum with chlorhexidine and chlorhexidine nanoparticle has shown more reduction of plaque index and gingival index than that with no chlorhexidine. 2. There could be seen a difference between the gum with chlorhexidine and the gum with chlorhexidine nanoparticle. 3. The gum with chlorhexidine nanoparticle has shown less level of plaque index than that chlorhexidine, which difference was only slight. 4. The gum with chlorhexidine nanoparticle wasn't absorved any tooth coloring. To put these results together, it is proposed that mixing chewing gum with chlorhexidine nanoparticle can be an efficient application.

• 로봇학회논문지
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• 제2권4호
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• pp.310-316
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• 2007

The paper proposes a human-following behavior of mobile robot and an intelligent space (ISpace) is used in order to achieve these goals. An ISpace is a 3-D environment in which many sensors and intelligent devices are distributed. Mobile robots exist in this space as physical agents providing humans with services. A mobile robot is controlled to track a walking human using distributed intelligent sensors as stably and precisely as possible. The moving objects is assumed to be a point-object and projected onto an image plane to form a geometrical constraint equation that provides position data of the object based on the kinematics of the intelligent space. Uncertainties in the position estimation caused by the point-object assumption are compensated using the Kalman filter. To generate the shortest time trajectory to track the walking human, the linear and angular velocities are estimated and utilized. The computer simulation and experimental results of estimating and trackinging of the walking human with the mobile robot are presented.

• 한국경영과학회지
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• 제39권1호
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• pp.1-12
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• 2014

This article proposes a variable sampling interval (VSI) $\bar{X}$ control chart using weighted standard deviation (WSD) method for skewed populations. The WSD method decomposes the standard deviation of a quality characteristic into upper and lower deviations and adjusts control limits and warning limits of a control chart in accordance with the direction and degree of skewness. A control chart constant is derived for estimating the standard deviation of skewed distributions with the mean of sample standard deviations. The proposed chart is compared with the conventional VSI $\bar{X}$ control chart under some skewed distributions. Simulation study shows that the proposed WSD VSI chart can control the in-control average time to signal (ATS) as an adequate level better than the conventional VSI chart, and the proposed chart can detect a decrease in the process mean of a quality characteristic following a positively skewed distribution more quickly than the standard VSI chart.

• 시스템엔지니어링학술지
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• 제8권2호
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• pp.57-67
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• 2012

It is the sensitivity and confidentiality of nuclear power plant decommissioning cost that prevent detailed cost information to be released to the public, which causes some limitation to analyze and reuse the costs. This limitation to access cost information means that the lessons learned from preceding cost estimating may not systematically feed back into following cost estimates. As an alternative, decommissioning cost estimation framework is indispensable to reflecting available experience and knowledge for decommission costs. This study provides the cost estimation framework including data flow and structuralization based on engineering and bottom up approach to enhance decommissioning cost estimation.

• 약학회지
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• 제59권1호
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• pp.6-11
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• 2015

A simple HPLC-UV method was developed and validated for the quantification of human serum isepamicin using phenylisocyanate as a derivatization agent. The linear calibration curve was obtained in the concentration range of $1{\sim}100{\mu}g/ml$ and LLOQ of $1{\mu}g/ml$. This method was validated with selectivity, linearity, precision and accuracy, leading to successful application for estimating the pharmacokinetic parameters of isepamicin in Korean healthy subjects following IV infusion of 800 mg isepamicin. The mean $t_{1/2}$ of isepamicin was $1.55{\pm}0.08hr$.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.109.1-109
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• 2001

This paper deals with the path following problem of car-like intelligent mobile robot. A robust sliding mode control law based on time-varying state feedback is performed via Lyapunov method for path tracking of nonholonomic mobile robot with uncertainties. At first, A sliding control law is designed by combing the natural algebraic structure of the chained form system with ideas from sliding mode theory. Then, a robust control law is proposed to impose robustness against bounded uncertainties in path tracking. The problem of estimating the asymptotic stability region and the sliding domain of uncertain sliding mode system with bounded control input is also discussed. The proposed sliding mode control law can ensure the global reaching condition of the uncertain control system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.235-239
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• 1992

The paper describes an approach for estimating unsteady flow rate through oil hydraulic pipelines and components in real time. Recently we have proposed following three unsteady flow rate measurement approaches; RIFM, QIFM and TPFM, in which hydraulic pipeline dynamics are made use of. In this paper, we firstly propose new approaches, i.e, an interpolation and an extrapolation methods in combination with RIFM and TPFM. In the interpolation method, unsteady flow rate at the arbitrary internal location along the pipeline between two points for measuring the two point pressure can be estimated. In this paper, the accuracy and dynamic response of interpolation method are mainly experimentally investigated in detail.