• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.387-390
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• 2002

In this paper, we accomplish uncertainty evaluation and performance test of the volumetric interferometer using two spherical wavefronts emitted from the ends of two single mode fibers. We verify that the volumetric interferometer has the volume uncertainty of 690nm through the error analysis and it has the resolution of 0.1 0.1$\mu\textrm{m}$ for x axis which is the same order of repeatability for x axis. Also, we obtain the systematic error of $1\mu\textrm{m}$ for $60\times 60\times 20 mm^3$ working volume using self-calibration with an artifact plate.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2004년도 학술발표회
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• pp.1285-1289
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• 2004

Elman Discrete Recurrent Neural Networks Model(EDRNNM) was used to be a suitable short-term hydrological forecasting tool yielding a very high degree of flood stage forecasting accuracy at Musung station of Wi-stream one of IHP representative basins in South Korea. A relative new approach method has recurrent feedback nodes and virtual small memory in the structure. EDRNNM was trained by using two algorithms, namely, LMBP and RBP The model parameters, optimal connection weights and biases, were estimated during training procedure. They were applied to evaluate model validation. Sensitivity analysis test was also performed to account for the uncertainty of input nodes information. The sensitivity analysis approach could suggest a reduction of one from five initially chosen input nodes. Because the uncertainty of input nodes information always result in uncertainty in model results, it can help to reduce the uncertainty of EDRNNM application and management in small catchment.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1564-1568
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• 2004

The requirements of internal balance were studied that should be considered on performing force & moment transonic wind tunnel testing to develop combat aircraft. In many insecure factors of test condition, uncertainty analysis was conducted to verify one drag count measurements. The analysis result was applied to T-50 aircraft model and compared for data verifaction. In conclusion, the aerodynamicist should estimate the validation and accuracy of test data by having an overall grasp of system components including internal balance. It will help him get high productivity of testing and effective validated data at tunnel.

• 한국산학기술학회논문지
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• 제18권4호
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• pp.248-259
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• 2017

본 연구는 항암화학요법을 받는 폐암환자의 불확실성과 불확실성 영향요인을 파악하기 위한 서술적 상관관계 연구이다. 연구 대상자는 일 대학병원에서 항암화학요법을 받고 있는 폐암환자 111명을 대상으로 하였다. 자료는 2014년 7월 25일부터 12월 31일까지 수집하였다. 수집된 자료는 SPSS Window 18.0 Program을 이용하였고, 빈도와 백분율, 평균과 표준편차, t-test, ANOVA, Scheffe test, median, standard deviations, Pearson's product moment correlation coefficient와 multiple regression analysis로 분석하였다. 연구 결과 항암화학요법을 받는 폐암환자의 불확실성은 평균 평점 2.61(${\pm}0.46$)점으로 다른 질병을 가진 환자의 불확실성 정도보다 높았다. 항암화학요법을 받는 폐암환자의 불확실성과 질병의 심각성, 증상의 일관성, 사건의 친숙성, 의료인에 대한 신뢰, 일상 활동 능력, 자기 효능감, 사회적 지지와의 관계를 분석한 결과 불확실성과 질병의 심각성 간의 상관계수는 .74(<.01), 불확실성과 증상의 일관성 간의 상관관계는 .27(<.01)이었다. 질병에 대한 심각성이 불확실성에 가장 영향을 미치는 변수로 나타났으며, 전체 설명력은 54%이었다. 이상에서 항암화학요법을 받는 폐암환자의 불확실성을 감소시키기 위한 간호중재가 필요할 뿐만 아니라 폐암 환자의 간호중재에는 질병의 심각성을 고려한 간호중재가 이루어져야 할 것이다.

• 성인간호학회지
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• 제17권2호
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• pp.230-238
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• 2005

Purpose: The purposes of this study were to explore the concept of uncertainty and to examine the relationships among uncertainty, appraisal of uncertainty, depression, anxiety, and perceived health status in patients with atrial fibrillation. Method: The study utilized a descriptive correlational survey design using a face to face interview method. A convenience sample of 49 subjects were recruited from K university hospital over 8 months. The data were analyzed by t-test, ANOVA, Pearson correlation and partial correlation analysis. Results: 1) Subjects perceived with moderately high uncertainty(M=65.98); moderate physical health(M=39.80), mental health(M=47.38), and general health(M=2.94); moderate anxiety(M= 44.78); and slightly low depression(M=15.33). 2) There were significant differences in uncertainty by gender and education. 3) Uncertainty and danger appraisal were significantly correlated(r=.32, p=.03) while the uncertainty was not associated with opportunity appraisal. 4) Uncertainty was significantly correlated with mental health(r=-.31, p=.04), anxiety(r=.38, p=.01), and depression(r=.37, p=.01). Conclusion: This study was the first trial to explore uncertainty and to examine the relationships among its associated factors in Korean patients with atrial fibrillation. Thus, based on the findings of this study, directions for nursing practice and further nursing research for patients with atrial fibrillation were suggested.

• Nuclear Engineering and Technology
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• 제52권4호
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• pp.755-763
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• 2020

The critical flow phenomenon has been studied because of its significant effect for design basis accidents in nuclear power plants. Transition points from thermal non-equilibrium to equilibrium are different according to the geometric effect on the critical flow. This study evaluates the uncertainty parameters of the critical flow model for analysis of DBA (Design Basis Accident) with the MARS-KS (Multi-dimensional Analysis for Reactor Safety-KINS Standard) code used as an independent regulatory assessment. The uncertainty of the critical flow model is represented by three parameters including the thermal non-equilibrium factor, discharge coefficient, and length to diameter (L/D) ratio, and their ranges are determined using large-scale Marviken test data. The uncertainty range of the thermal non-equilibrium factor is updated by the MCDA (Model Calibration through Data Assimilation) method. The updated uncertainty range is confirmed using an LBLOCA (Large Break Loss of Coolant Accident) experiment in the LOFT (Loss of Fluid Test) facility. The uncertainty ranges are also used to calculate an LBLOCA of the APR (Advanced Power Reactor) 1400 NPP (Nuclear Power Plants), focusing on the effect of the PCT (Peak Cladding Temperature). The results reveal that break flow is strongly dependent on the degree of the thermal non-equilibrium state in a ruptured pipe with a small L/D ratio. Moreover, this study provides the method to handle the thermal non-equilibrium factor, discharge coefficient, and length to diameter (L/D) ratio in the system code.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1456-1459
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• 1997

In this paper, a control system using robust H.inf. controller based on convex parametrization is presented for nonlinear system with uncertainty. accounting for the time delay, noise and linearization error by frequency analysis, the suboptmal controller is designed to meet robust stability and performance for uncertainty. The desinged control system is applied to a nonlimear boiler moderl to test its performances.

• 한국전기전자재료학회논문지
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• 제21권1호
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• pp.53-56
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• 2008

The commercial parallel plate electrodes system with guard-ring electrode have been widely used for measurement of dielectric constants of solid materials. And the specification of the electrodes system is about 1 % of measurement uncertainty. This measurement uncertainty is only estimated the error come from mechanical measurements such as the area of the electrodes and the gap between the electrodes except the error come from the air gap between the electrodes and dielectric specimen. Because it is impossible to measure the air gap. This study analyze the total measurement uncertainties of the commercial dielectric constant test cell using 3 kinds of Standard Reference Materials. As a results, the total measurement uncertainty is much bigger than 1 % and the most of the uncertainty can be reduced by compensation of the error values evaluated in this study.

• 한국기계가공학회지
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• 제11권4호
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• pp.55-61
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• 2012

Very important content in performance evaluation of machine tool is positioning accuracy and repeatability precision measurements of feed mechanism. A study analyses the measurement method and uncertainty factors by ISO-based test method. Reliable results can't be derived without the notion of measurement uncertainty. The reason is that the measured value includes a lot of uncertain factors. Finding the factor that affects the measurement of parameter is important for estimation of measurement precision. In this paper, the evaluation of uncertainty analysis about positioning accuracy and repeatability precision measurements of high precision feed mechanism is presented to evaluate the important factors of uncertainty.

• Journal of the Korean Data and Information Science Society
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• 제27권1호
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• pp.9-18
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• 2016

모수불확실성을 반영하는 손실모형으로는 Heckman과 Meyers가 제안한 모형이 주로 인용되고 있다. 이 모형은 모수 자체가 어떤 확률분포를 따른다는 가정을 하고 있으며 IAA, Swiss Solvency Test, EU Solvency II 등에서 참고하고 있다. 반면 베이지안 기법을 이용한 연구는 모수에 대한 선험적 정보 즉, 사전분포를 이용하여 모수불확실성을 반영한다. 그러나 현실에서는 두 가지 방법을 동시에 고려해야 하는 상황이 빈번히 발생한다. 이에 본 연구는 Heckman-Meyers의 모형과 베이지안 접근법을 동시에 고려한 베이지안 H-M CRM모형을 제안하고 그 특성을 분석하였다.