• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 봄 학술발표회논문집
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• pp.85-91
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• 2000

The smallest value of the load when the equilibrium condition becomes to be unstable is defined as the buckling load. The primary objective of this paper is to analyse stability boundaries for star dome under combined loads and is to investigate the iteration diagram under the independent loading parameter In numerical procedure of the geometrically nonlinear problems, Arc Length Method and Newton-Raphson iteration method is used to find accurate critical point(bifurcation point and limit point). In this paper independent loading vector is combined as proportional value and star dome was used as numerical analysis model to find stability boundary among load parameters and many other models as multi-star dome and arches were studied. Through this study we can find the type of buckling mode and the value of buckling load.

• Communications for Statistical Applications and Methods
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• 제10권3호
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• pp.931-954
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• 2003

It is widely recognized that economic time series involved not only the linearities but also the non-linearities. In this paper, when the economic time series data have the nonlinear characteristics we propose the forecasts method using combinations of both forecasts from linear and nonlinear models. In empirical study, we compare the forecasting performance of 4 exchange rates models(AR, GARCH, AR+GARCH, Bilinear model) and combination of these forecasts for dairly Won/Dollar exchange rates returns. The combination method is selected by the estimated individual forecast errors using Monte Carlo simulations. And this study shows that the combined forecasts using unrestricted least squares method is performed substantially better than any other combined forecasts or individual forecasts.

• 한국정밀공학회지
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• 제9권1호
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• pp.53-65
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• 1992

For improving the performance of maglev systems with a combined lift and guidance, it is suggested that the multivariable control systems and a secondary suspension should be added. The former is required to reject both track irregularities in vertical disturbances and wind gusts in lateral disturbances, and the latter to guarantee passengers against an unsatisfied criteria in ride quality. In this paper, bond graph model for the study of nonlinear dynamics of maglev systems with a combined lift and guidance is presented briefly. And, the secondary suspension is analyzed to understand the role of stiffness and damping factors in passive devices. Finally, LQG/LTR mulitivariable control systems are designed for the overall maglev systems with and without secondary suspension, and then the system performances in these two cases are evaluated.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1091-1097
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• 1991

A logical and systematic procedure to derive a mathematical model for magnetically levitation(maglev) systems with a combined lift and guidance is developed by using and graph. First, bond graph is constructed for the energy-feeding system with magnetic leakage flux. And, the overall maglev system in which lift and guidance dynamics are coupled is modeled by using the concept of multi-port field in bond notations. Finally, the LQG/LTR control systems are designed for single-input single-output and for multi-input multi-output maglev systems. In this paper, it has been shown that the bond graph is an excellent method for modeling multi-energy domain systems such as maglev systems and the multivariable control system is required to improve the performance of the maglev system with a combined lift and guidance.

• Journal of the Korean Data and Information Science Society
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• 제19권2호
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• pp.597-608
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• 2008

Marketing has been used the power of data and information technology in the pursuit of personal marketing of products and service to customers, based on their preferences and needs. We analyzed the performance of twenty six combined(RFM and Confidence) response modeling methods that were proposed by Zahavi and Levin(l997) and Sho, et al.(1999). As a result, we were able to increase about 3.5%p. forecasting accuracy of customers response through combination with confidence(C) that is able to consider characteristics of product than using the single RFM model that is practically the most widely used.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 추계학술대회논문집
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• pp.144-147
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• 2003

In order to evaluate spring-back behavior in automotive sheet forming processes, a panel shape idealized as a SS-rail has been investigated. After spring-back kas been predicted fer SS-rails using the finite element analysis, results has been compared with experimental measurements for three automotive sheets. To account for hardening behavior such as the Bauschinger and transient effects in addition to anisotropic behavior, the combined isotropic-kinematic hardening law based on the Chaboche type single-surface model and a recently developed non-quadratic anisotropic yield function have been utilized, respectively.

• Molecules and Cells
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• 제20권1호
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• pp.35-42
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• 2005

A novel combined method for locating box H/ACA small nucleolar RNAs (snoRNAs) is described, together with a software tool. The method adopts both a probabilistic hidden Markov model (HMM) and a minimum free energy (MFE) rule, and filters possible candidate box H/ACA snoRNAs obtained from genomic DNA sequences. With our novel method 12 known box H/ACA snoRNAs, and one strong candidate were identified in 30 nucleolar protein genomic sequences.

• 대한안전경영과학회지
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• 제9권1호
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• pp.145-156
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• 2007

This paper is to propose model classification and evaluation of measurement uncertainty. In order to obtain type A and B uncertainty, variety of measurement mathematical models are illustrated by example. The four steps to evaluate expanded uncertainty are indicated as following; First, to get type A standard uncertainty, measurement mathematical models of single, double, multiple, design of experiment and serial autocorrelation are shown. Second, to solve type B standard uncertainty measurement mathematical models of empirical probability distributions and multivariate are presented. Third, type A and B combined uncertainty, considering sensitivity coefficient, linearity and correlation are discussed. Lastly, expanded uncertainty, considering degree of freedom for type A, B uncertainty and coverage factor are presented with uncertainty budget. SPC control chart to control expanded uncertainty is shown.

• 전기학회논문지
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• 제57권8호
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• pp.1327-1333
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• 2008

Since Cost Based Pool markets has been continued to power markets, Genco. needs economic analysis about investment in power plants. Particularly most Private Genco.s have presently a construction plan about LNG combined cycle thermal power plants. In this paper, we propose a economic analysis method of LNG combined cycle thermal power plants using Economic Dispatch and Optimal Power Flow in CBP markets. Also we develope computation model using it for decision making to build a plant. This method can consider a variation of power facility like power plants and transmission lines in CBP markets. Finally, this dissertation provides a relevant case study to confirm the effect of cost factor to economical efficiency.

• 한국컴퓨터정보학회논문지
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• 제26권7호
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• pp.9-17
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• 2021

본 연구는 대장암 환자의 치료방법 중 하나인 항암화학요법을 분류할 수 있는 시스템인 CDSS연구의 일환으로 시행되었다. 대장암 치료에서 환자의 상태에 맞는 항암화학요법의 선택은 환자의 생존 기간과 직결되기 때문에 매우 중요하다. 따라서 본 연구에서는 대장암 환자의 개인적, 병리학적 특성을 사용해 기저 모델, 병리학적 모델, 그리고 환자의 두 가지 특성을 모두 사용한 결합 모델을 만들어 머신러닝 알고리즘으로 항암화학요법을 분류하였다. Top-n Accuracy와 ROC 곡선, AUC로 모델의 예측 정확도를 비교한 결과, 결합 모델에서 가장 우수한 예측 정확도를 보였으며, LGBM 알고리즘의 성능이 가장 우수한 것을 알 수 있었다. 본 연구에서는 머신러닝 알고리즘을 이용해 환자 특성별 모델을 분류함으로써 환자의 상태에 맞는 항암화학요법 분류 모델을 구축하였다. 향후 연구에서 본 연구 결과를 기초한다면 더 좋은 성능의 항암화학요법 분류 모델을 만들어 CDSS 연구에 도움이 될 것이다.