• 대한산업공학회지
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• 제39권1호
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• pp.1-9
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• 2013

The current manufacturers have generated tremendous amount of digitized product data to efficiently share and exchange it with other stakeholders or various software systems for product development. The digitized product data is a valuable asset for manufacturers, and has a potential to support high level strategic decision makings needed at many stages in product development. However, the lack of studies on extraction of key performance indicators(KPIs) from product data management(PDM) databases has prohibited manufacturers to use the product data to support the decision makings. Therefore this paper examines a possibility of an architecture that supports KPIs for evaluation of product development performances, by applying multidimensional product data model and on-line analytic processing(OLAP) to operational databases of product data management. To validate the architecture, the paper provides a prototype product data management system and OLAP applications that implement the multidimensional product data model and analytic processing.

• 한국대기환경학회지
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• 제16권5호
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• pp.539-544
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• 2000

A simple analytic model is proposed here to analyze the concentration deficit field caused by a large area of vegetated area. With non-dimensional deposition velocity chosen as small parameter, the regular perturbation method is exploited to derive the mass balance equation and the dynamic equations for the concentration deficit field, Analytic solutions to those equations are obtained in a closed form for several cases of interest, assuming that the concentration field is stationary and the plume can be nicely approximated as Gaussian for a point source. The results suggest that quite a negligible fraction (less than 1%) of the gaseous air pollutants emitted into the air is removed by the vegetated area of which width is 4 km in wind-wise direction, the typical dimension of the Restricted Development Zones around the metropolitan regions in South Korea.

• 대한안전경영과학회지
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• 제17권1호
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• pp.1-11
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• 2015

The efficient safety estimation for a business should analyze an accident data by considering every possible and potential factor. Thus, we consider several factors to build the safety estimation model to meet fairness and rationality. This paper present the yearly statistic data of accident from KOSHA analyze the data by industry, scale, year of service of a employee, age and other factors; build the safety estimation model for the business based on the accident report derived the analysis. The estimation model is established by the weights for accident type, degree, scale, industry, year of service, and age of the employee derived from ANP(Analytic Network Process).

• Nuclear Engineering and Technology
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• 제31권1호
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• pp.80-87
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• 1999

An analytic axial xenon oscillation model was developed for pressurized water reactor analysis. The model employs an equation system for axial difference parameters that was derived from the two-group one-dimensional diffusion equation with control rod modeling and coupled with xenon and iodine balance equations. The spatial distributions of nu, xenon, and iodine were expanded by the Fourier sine series, resulting in cancellation of the flux-xenon coupled non-linearity. An inhomogeneous differential equation system for the axial difference parameters, which gives the relationship between power, iodine and xenon axial differences in the case of control rod movement, was derived and solved analytically. The analytic solution of the axial difference parameters can directly provide with the variation of axial power difference during xenon oscillation. The accuracy of the model is verified by benchmark calculations with one-dimensional reference core calculations.

• 대한안전경영과학회지
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• 제12권2호
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• pp.1-7
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• 2010

The efficient safety estimation for a business should analyze an accident data by considering every possible and potential factor. Thus, we consider several factors to build the safety estimation model to meet fairness and rationality. This paper present the yearly statistic data of accident from KOSHA analyze the data by industry, scale, year of service of a employee, age and other factors; build the safety estimation model for the business based on the accident report derived the analysis. The estimation model is established by the weights for accident type, degree, scale, industry, year of service, and age of the employee derived from AHP(Analytic Hierarchy Process).

• 한국문헌정보학회지
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• 제38권3호
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• pp.103-118
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• 2004

인터넷 서비스가 안정화 위주로 옮겨가면서 웹서비스의 품질 향상을 위해 보다 많은 투자가 이루어지고 있다. 대규모의 다양한 정보를 제공하고있는 전자도서관 웹 사이트가 객관적인 평가 시스템을 개발하여 적용하므로써 이용자들에게 서비스의 만족도를 높일 수 있는 기준을 마련할 필요가 있다. 본 연구에서는 검색성, 개인화로 기준을 도출하였다. 구축된 사용성 평가 모델을 계층적 분석방법(Analytic Hierarchy Process AHP)을 이용하여 평가하고 검증하였다. 평가지침으로 설정된 항목을 설문조사를 하여 계층적 분석방법에 기초한 디지털 도서관 웹 사이트 평가 모델을 개발하였다.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.238-243
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• 2003

As there are many advantages on underground caverns, such as safety and operation, they can also be used for gas storage purpose. When liquefied gas is stored underground, the cryogenic temperature of the gas will affect the stability of the storage cavern. In order to store the liquefied gas successfully, it is essential to estimate the exact temperature distribution of the rock mass around the cavern. In this study, an analytic solution and a conceptual model that can estimate three-dimensional temperature distribution around the storage cavern are suggested. When calculating the heat transfer within a solid, it is likely to consider the solid as the intersection of two or more infinite or semi-infinite geometries. Therefore heat transfer solution for the solid is expressed by the product of the dimensionless temperatures of the geometries, which are used to form the combined solid. Based on the multi-dimensional transient heat transfer theory, the analytic solution is successfully derived by assuming the cavern shape to be of simplified geometry. Also, a conceptual model is developed by using the analytic solution of this study. By performing numerical experiments of this multi-dimensional model, the temperature distribution of the analytic solution is compared with that of numerical analysis and theoretical solutions.

• 한국정보과학회논문지:정보통신
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• 제35권1호
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• pp.56-66
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• 2008

무선 애드-혹 망에서 경쟁기반 전달방식은 다중 수신자 중에서 채널상태가 최적인 수신자를 선택하므로 전송실패율을 낮춘다. 그러나, 경쟁기반 전달방식은 다중 수신자간에 동시전송에 따른 충돌문제로 인하여 전송지연을 증가시킬 수 있다. 본 논문에서는 손실이 있는 무선 링크 환경에서 경쟁기반 전달방식이 경험할 수 있는 지연 및 충돌을 반영한 분석모델을 제시한다. 분석모델을 통해서 무선링크모델 및 지연모델에 따른 단일-홉 전송에서의 기대되는 전송지연(delay)과 목적지로의 전진(progress)을 구한다. 분석결과로써 최적의 지연 및 전진을 얻기 위해서는 무선링크의 특성이 고려된 지연모델이 선택되어야함을 밝힌다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.45-54
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• 2012

In order to predict trailing edge noise from a flat plate more effectively and accurately, the prediction algorithm based on semi-analytic model for point pressure spectrum is proposed. The semi-analytic model consists of empirical models for point pressure spectra and theoretical model to determine the boundary layer characteristics needed for the empirical models. The proposed methods are applied to predict the trailing edge noise of the flat plate located in the mean flow of speed 38 m/s, for which the measured data are available. In present study, six empirical models for point pressure spectra are utilized for the predictions of trailing edge noise and their prediction results are compared to the measured data. Through the analysis of these comparisons, it is revealed that the present method based on non-frozen formula using Efimtsov model and Smol'yakov-Tkachenko model can provide more accurate and efficient predictions of trailing edge noise.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제5권9호
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• pp.411-418
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• 2016

교수-학습 지원 시스템에서 교수자와 학습자의 참여 활동 데이터를 활용하여 성공적으로 과정을 이수할 수 있도록 지원하기 위해 학습 분석이 활용되고 있다. 즉, 학습 분석은 학습자의 학습활동을 이해하기 위한 방법이다. 교수-학습 활동 데이터를 보다 유용하게 활용하기 위해서는 데이터 모델이 필요하다. 이에 본 연구에서는 사용자 중심의 학습양식과 학습객체 데이터모델(LSLODM)을 제안한다. 이는 사용자, 학습양식, 학습객체, 학습활동을 결합하여 표현한 것이다. LSLODM은 이를 기반으로 교수-학습 데이터를 수집하고, 교수-학습 활동 요소의 속성들을 최근성, 빈도성, 지속성을 정량적으로 파악할 수 있도록 한 것이다. 즉, 단위 과목에서 학습자의 교수-학습 활동을 분석할 수 있는 토대를 마련한 것이다.