• 대한안전경영과학회지
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• 제3권2호
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• pp.113-121
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• 2001

Today, facilities are composed of many complex components or parts. Because of this characteristics, the frequency of failures is decreasing, but the strength of failures is increasing; therefore, the failure analysis about many complex components or parts was needed. In the former research about Fault Tree Analysis, failure data of similar facilities have been used for forecasting about target system or components, but in case that the system or components for forecasting failure is new or qualitative and quantitative data are given simultaneously, there are many difficulty in using Fault Tree Analysis with this incorrect failure data. Therefore, this paper deal with the Fault Tree Analysis method which be applied with Fuzzy theory in above case. In case that , therefore, if there is no the correct failure data, it is represented a system or components as qualitative variable. subsequently, it converted to the quantitative value using fuzzy theory, and the values used as the value for failure forecast.

• 경영정보학연구
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• 제5권1호
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• pp.129-146
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• 2003

기술 투자와 거래의 증가는 기술가치 평가에 대한 관심을 증대시키고 있으나 평가의 전문성과 기술가치의 다양성으로 인해 객관적인 기술 가치 평가가 용이하지 않은 문제점을 가지고 있다. 이 연구는 웹 기반의 대화형 기술가치 평가(WITV) 시스템을 개발하고 이 시스템을 이용한 기술가치의 평가 및 기술가치의 전략 분석에 그 목적을 두고 있다. WITV 시스템은 내적 기술가치(IVT)와 외적 기술가치(EVT)로 구성 된 기술가치 매력도(TVA) 모형을 이용하여 기술가치를 평가하고 해당 산업에서 기술의 가치를 제고하기 위한 전략을 분석하는데 이용되고 있다. 이 연구는 코스닥에 등록된 IT산업 의 중소 제조기업을 대상으로 TVA 모형과 WITV 시스템의 타당성과 적용가능성을 실험하였으며, 실험결과에 의해 그 효용성을 검증하였다.

• 한국대기환경학회지
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• 제19권5호
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• pp.595-610
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• 2003

The statistical indexes such as RMSE (Root Mean Square Error), Mean Bias error, and IOA (Index of agreement) are used to evaluate 3 Dimensional wind and temperature fields predicted by operational meteorological model RAMS (Regional Atmospheric Meteorological System) implemented in CARIS (Chemical Accident Response Information System) for the dispersion forecast of hazardous chemicals in case of the chemical accidents in Korea. The operational atmospheric model, RAMS in CARIS are designed to use GDAPS, GTS, and AWS meteorological data obtained from KMA (Korean Meteorological Administration) for the generation of 3-dimensional initial meteorological fields. The predicted meteorological variables such as wind speed, wind direction, temperature, and precipitation amount, during 19 ∼ 23, August 2002, are extracted at the nearest grid point to the meteorological monitoring sites, and validated against the observations located over the Korean peninsula. The results show that Mean bias and Root Mean Square Error are 0.9 (m/s), 1.85 (m/s) for wind speed at 10 m above the ground, respectively, and 1.45 ($^{\circ}C$), 2.82 ($^{\circ}C$) for surface temperature. Of particular interest is the distribution of forecasting error predicted by RAMS with respect to the altitude; relatively smaller error is found in the near-surface atmosphere for wind and temperature fields, while it grows larger as the altitude increases. Overall, some of the overpredictions in comparisons with the observations are detected for wind and temperature fields, whereas relatively small errors are found in the near-surface atmosphere. This discrepancies are partly attributed to the oversimplified spacing of soil, soil contents and initial temperature fields, suggesting some improvement could probably be gained if the sub-grid scale nature of moisture and temperature fields was taken into account. However, IOA values for the wind field (0.62) as well as temperature field (0.78) is greater than the 'good' value criteria (> 0.5) implied by other studies. The good value of IOA along with relatively small wind field error in the near surface atmosphere implies that, on the basis of current meteorological data for initial fields, RAMS has good potentials to be used as a operational meteorological model in predicting the urban or local scale 3-dimensional wind fields for the dispersion forecast in association with hazardous chemical releases in Korea.

• 한국지구과학회지
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• 제35권1호
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• pp.41-53
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• 2014

겨울철 동해안 강수 현상에 대한 규명을 위하여 라디오존데를 활용한 특별관측을 2012년 1월 5일부터 2월 29일까지 실시하였고, 이 연구는 대기의 불안정을 나타내는 다양한 변수를 활용하여 강수 사례의 분석을 수행하였다. 그 결과, 강수가 발생할 때 지표면(1000 hPa)에서 중층(약 750 hPa)까지의 상당온위가 증가하는 것을 볼 수 있었고, 이러한 대기층(1000~750 hPa)은 불안정을 일으키기에 충분한 수준의 수증기를 함유하고 있었다. 대류가용잠재에너지의 시간적인 변화를 살펴본 결과 강수가 발생하였을 때 증가하는 것을 볼 수 있었고, 연직바람쉬어의 경우에서도 대류가용잠재에너지와 마찬가지로 강수 기간 동안 상승하여 일정수준 이상의 값을 유지하는 것을 확인할 수 있었다. 강수에 따른 대기 구조의 상세한 분석을 위하여 지상 원격 탐사 자료와 지상 관측 자료를 활용하여 분석을 수행하였다. 또한 가강수량과 바람벡터를 이용하여 가강수량플럭스를 계산하였다. 가강수량플럭스와 강수량은 북동풍 계열의 바람이 발생하였을 때 높은 관계성을 보였다. 그 결과 동해안영역에서 발생하는 강수 현상에서는 풍계와 같은 역학적인 작용의 이해가 중요한 것으로 판단되었다.

• 한국치위생학회지
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• 제6권1호
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• pp.25-35
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• 2006

The purpose of this study is to forecast patient satisfaction and service value through the staged regression analysis of the relation between each factor and its satisfaction and service value, following the measurement of the quality of dental care service that patients recognize. And a self-administered survey was used for this study. The subjects of this survey were 394 outpatients of dental clinics located in K city in the period from Dec. 5, 2004 to Feb. 19, 2005, the questionnaire was composed of a total of 31 questions to measure the quality of overall dental care service(22 questions), the patient satisfaction(6 questions) and the service value(3 questions). The 7 points Likert scale ranging from "very poor"(1-point) to "very high"(7-point) was used for these questions The results of study could be summarized as follows: 1. The most useful index to predict patient satisfaction turned out to be "internal environment", followed by "treatment process and waiting time", "dentist", "external environment", and "dental hygienist". 2. The service value had a significant effect on the "internal environment", "dentist", "treatment process and waiting time". 3. The most useful index to predict the service value turned out to be "treatment process and waiting time", followed by "internal environment" and "dentist". Today, the quality of dental care service is becoming a prime concern since it is directly connected to a matter of survival of medical service organizations. Dental clinics desperately need patient-oriented marketing strategies in order to actively cope with changing medical environment. They also need to thoroughly examine possible measures to maximize the service value by establishing a variety of service strategies which can promote service quality that patients recognize.

• 한국건설관리학회논문집
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• 제4권3호
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• pp.137-145
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• 2003

건설공사관리체계는 실적자료를 바탕으로 운영되어야 하며, 공사실적을 정확하게 파악하기 위해서는 합리적인 건설공사진도 율 측정기준 및 그에 따른 진도 율 산정방법이 필요하다. 본 연구에서는 건설공사관리체계 구축에 필수적인 건설공사진도율 산정시스템 개발 및 그 시스템의 합리적인 운용 방안을 제시하였다. 그 방법으로서 분할된 단위작업들은 공사 진행에 따라 집행된 내역물량을 기준으로, 상위레벨의 작업범위에 대하여는 실행기성(earned value)을 바탕으로 건설공사의 진도 율을 산정 할 수 있는 시스템(construction progress measurement system; CPMS)을 제시하였다 일반 PC의 Window환경에서 제공되는 프로그래밍 인터페이스(interface) 기능인 ODBC(Open DataBase Connectivity)는 상이한 프로그램간의 데이터 교환을 통해 정보공유를 가능케 하고 있다 본 연구에서 제시하는 건설공사진도 율 산정 시스템은 ODBC를 통해, 상용 일정관리프로그램을 활용해서 생성된 데이터를 그대로 이용하고, 시스템 내에서 생성된 데이터는 일정관리프로그램에 갱신(update)된 정보로 제공된다. 제안된 건설공사진도 율 측정시스템의 실용화를 촉진시키기 위해서는 진도 율 측정에 의한 수치 값을 분석하여 향후 공사의 전망 등을 예측할 수 있어야 하는데 이에 대한 연구가 필요하다.

• 산업경영시스템학회지
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• 제22권49호
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• pp.43-57
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• 1999

The recent trend is that risk management has more and more its importance. Neverthless, Korea's risk management is not developed. Even most banks does gap, duration in ALM for risk management, development and operation of VaR stressed at BIS have elementary level. In the case of Fallon and Pritsker, Marshall, gamma model is superior to delta model and Monte Carlo Simulation is improved at its result, as sample number is increased. And, nonparametric model is superior to parametric model. In the case of Korea's stock portfolio, VaR of Monte Carlo Simulation and Full Variance Covariance Model is less than that of Diagonal Model. The reason is that VaR of Full Variance Covariance Model is more precise than that of Diagonal Model. By the way, in the case of interest rate, result of monte carlo simulation is less than that of delta-gamma analysis on 95% confidence level. But, result of 99% is reversed. Therefore, result of which method is not dominated. It means two fact at forecast on volatility of stock and interest rate portfolio. First, in Delta-gamma method and Monte Carlo Simulation, assumption of distribution affects Value at Risk. Second, Value at Risk depends on test method. And, if option price is included, test results will have difference between the two. Therefore, If interest rate futures and option market is open, Korea's findings is supposed to like results of other advanced countries. And, every banks try to develop its internal model.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2002년도 학술.기술논문발표회
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• pp.103-109
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• 2002

This research is aiming to specify the requirement of the investment such as initial cost, running cost earning rate to make effective investment considering the purpose of remodeling and economical value of store building enough to meet the initial purpose of remodeling. The review of earning rate for economical evaluation was performed by the on-site auditing on the structure and function of the building and applying the assessment simulation program, which is to find the possible business model to identify the requirement of building owner through case study. After the research, the following results are obtained. First, it is important that many aspects should be carefully analysis and the best method should be selected as characteristics of remodeling can be defer each other in their implementations. Second, though the remodeling of exist buildings to promote the functions has been applied. no suitable assessment tool has bee developed for deciding the level of remodeling in the view of economical efficiency so far. Third, the economical benefit was evaluated by analysing annual earning rate which is applied by investment items and recovery period for the investment. More specific data bate should be established to apply the suggested economic accession in business enough to forecast the future circumstances. More researches should be promoted on this area continuously as well as the integrated economic evaluation of remodeling on existing building.

• 한국태양에너지학회 논문집
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• 제23권1호
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• pp.57-67
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• 2003

This study aims to presents Evaluation Method of Green Remodeling that analyze the value of environment through expense, using the method of life cycle cost and life cycle assessment simultaneously. The results of this study are summarized as follows. Evaluation Model developed in this study can convert economical value of environment into cost by integrating. In addition, the model can apply as a useful tool to estimation of economical design alternative as well as quantification of environmental loads and costs. Evaluation Model presented In this study observe energy consumption and the environmental load emission with qualification, it can forecast effect of environmental cost that cost estimation is expected to be added to energy cost rate by being possible. Synthetically, when Estimation Model and computer program that developed in this study is applies to the construction industry; reasonable management of environmental load is convenient at each step of Green Remodeling. In addition, at preliminary design phase, practical use may be possible by reasonable yardstick about various alternatives and improvement of design alternatives likewise by grasping environmental effect.

• 대기
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• 제32권4호
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• pp.263-276
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• 2022

The observation error of satellite radiation data that assimilated into the Korean Integrated Model (KIM) was diagnosed by applying the Hollingsworth and Lönnberg and Desrozier techniques commonly used. The magnitude and correlation of the observation error, and the degree of contribution for the satellite radiance data were calculated. The observation errors of the similar device, such as Advanced Technology Microwave Sounder (ATMS) and Advanced Microwave Sounding Unit-A shows different characteristics. The model resolution accounts for only 1% of the observation error, and seasonal variation is not significant factor, either. The observation error used in the KIM is amplified by 3-8 times compared to the diagnosed value or standard deviation of first-guess departures. The new inflation value was calculated based on the correlation between channels and the ratio of background error and observation error. As a result of performing the model sensitivity evaluation by applying the newly inflated observation error of ATMS, the error of temperature and water vapor analysis field were decreased. And temperature and water vapor forecast field have been significantly improved, so the accuracy of precipitation prediction has also been increased by 1.7% on average in Asia especially.