• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.407-410
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• 2006

This study describes a simulation of two-dimensional bubble forming and motion by the Lattice Boltzmann Method with the phase field equation. The free energy model is used to treat the interfacial force and deformation of binary fluids system, drawn into a T-junction the micro channel. A numerical simulation of a binary flow in a cross-junction channel is carried out by using the parallel computation method. The aim in this investigation is to examine the applicability of LBM to numerical analysis of binary fluid separation and motion in the micro channel.

• 한국경영과학회지
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• 제27권2호
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• pp.33-49
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• 2002

CBM (Condition-Based Maintenance) has increasingly drawn attention in industry because of its many benefits. CBM Problem Is characterized as a state-dependent scheduling model that demands simultaneous maintenance actions, each for an attribute that influences on machine condition. This problem is very hard to solve within conventional Markov decision process framework. In this paper, we present an intelligent machine maintenance scheduler, for which a new incremental decision tree learning method as evolutionary system identification model and shortest path problem as schedule generation model are developed. Although our approach does not guarantee an optimal scheduling policy in mathematical viewpoint, we verified through simulation based experiment that the intelligent scheduler is capable of providing good scheduling policy that can be used in practice.

• 한국해안해양공학회지
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• 제5권3호
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• pp.250-262
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• 1993

기조력항이 포함된 2차원 조석모형을 사용하여, 동해에서의 주사개분조(M$_2$, S$_2$, $K_1$, $O_1$)에 대해 산정된 조석도가 제시되었다. 모형의 결과에서 기조력항의 포함은 반일주조의 무조점위치에는 영향을 주고 있으나 전반적으로 계산결과는 연안관측치와 비교하여 근사한 값을 보였으며 또한 이 해역에서의 기존의 경험적인 조석도와 비교하여 유사한 결과를 나타냈다.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1997년도 추계학술대회논문집
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• pp.351-356
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• 1997

A global model of simulator sickness is outlined that suggests the sequence of events leading to the development of simulator aftereffects. The model attempts to link coupling effects of illusory self-motion(vection) and compensatory head sway to the origin of simulator sickness. A pilot study was conducted in support of a rescarch program that will investigate the proposed model. Seven males and four females participated in a 5-min scssion in a fixed-base automobile simulator. Due to restricted sample size, descriptive statistics are presented for measures of simulator sickness, lateral sway velocity (Y-velocity), driving performance, control inpuls, and vection ratings. Although potential trends are discussed, no statistical conclusions can be drawn. Measurement issures for te next phase of reasearch mclude increasing the sensitivity of vection ratings, and examination of the timecourse got development of compensatory sway.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제5권3호
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• pp.253-258
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• 2005

In this study, we introduce a new category of fuzzy inference systems based on information granulation to carry out the model identification of complex and nonlinear systems. Informal speaking, information granules are viewed as linked collections of objects (data, in particular) drawn together by the criteria of proximity, similarity, or functionality. To identify the structure of fuzzy rules we use genetic algorithms (GAs). Granulation of information with the aid of Hard C-Means (HCM) clustering algorithm help determine the initial parameters of fuzzy model such as the initial apexes of the membership functions and the initial values of polynomial functions being used in the premise and consequence part of the fuzzy rules. And the initial parameters are tuned effectively with the aid of the genetic algorithms and the least square method (LSM). The proposed model is contrasted with the performance of the conventional fuzzy models in the literature.

• 경영과정보연구
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• 제15권
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• pp.147-164
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• 2004

The purpose of this paper is on employees as internal customers and the critical role this group plays in the delivery of quality results. The set up of research model for verification was as follows. The research model was drawn as internal service quality level $\Rightarrow$ internal customer satisfaction $\Rightarrow$ enterprise outcome. Then, two hypotheses were established to the research model. Through the factor analysis and multiple regression analysis, the results are as follows. First, internal service quality level turned out to be affected indirectly through internal customers' satisfaction rather than a direct factor to affect the enterprise outcome. Second, internal customers' satisfaction was proved to be the most important factor for the enterprise outcome as ti was the intimate factor precedent to the enterprise outcome. However, there could be a variation of response according to the personal circumstances of respondents since the respondents were from different enterprises and consisted various job positions and age group. Namely it included a limitation of rather unaccurate resulting values because the transverse methods were performed for convenience though it needed a longitudinal research to accomplish the general purpose of this study.

• Steel and Composite Structures
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• 제20권6호
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• pp.1237-1257
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• 2016

The paper concerns analysis of effects of shrinkage of slab concrete in a steel-concrete composite deck of a through truss bridge span. Attention is paid to the shrinkage alongside the span, i.e., transverse to steel-concrete composite cross-beams. So far this aspect has not been given much attention in spite of the fact that it affects not only steel-concrete decks of bridges but also steel-concrete floors of steel frame building structures. For the problem analysis a two-dimensional model is created. An analytical method is presented in detail. A set of linear equations is built to compute axial forces in members of truss girder flange and transverse shear forces in steel-concrete composite beams. Finally a case study is shown: test loading of twin railway truss bridge spans is described, verified FEM model of the spans is presented and computational results of FEM and the analytical method are compared. Conclusions concerning applicability of the presented analytical method to practical design are drawn. The presented analytical method provides satisfactory accuracy of results in comparison with the verified FEM model.

• 산업경영시스템학회지
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• 제33권2호
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• pp.89-96
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• 2010

This study explores the application of the analytic network process (ANP) approach for the evaluation of R&D projects with heterogeneous objectives. The ANP model in this study produced the final priorities of projects with respect to several performance measures when there are interdependencies between research objectives and performance measures. The paper provides value to practitioners by providing a generic model for R&D project evaluation. The ANP approach is tested against empirical data drawn from fourteen R&D projects under six different objective programs sponsored by the Korean government.

• Journal of the Korean Data and Information Science Society
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• 제23권3호
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• pp.587-593
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• 2012

We study Bayesian estimates for finite population proportions in multinomial problems. To do this, we consider a three-stage hierarchical Bayesian model. For prior, we use Dirichlet density to model each cell probability in each cluster. Our method does not require complicated computation such as Metropolis-Hastings algorithm to draw samples from each density of parameters. We draw samples using Gibbs sampler with grid method. We apply this algorithm to a couple of simulation data under three scenarios and we estimate the finite population proportions using two kinds of approaches We compare results with the point estimates of finite population proportions and their standard deviations. Finally, we check the consistency of computation using differen samples drawn from distinct iterates.

• 교육시설
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• 제15권6호
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• pp.39-46
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• 2008

The main purpose of this study is to find out the strengths and weaknesses of the application of BIM to the educational facilities. All the data information is drawn from the integrated design process which links various fields such as energy simulation, structure analyzation, and etc, and it is applied to the project combined as one data set. Moreover, we analyze the possible problems of the data exchange that can happen as collaborating with various fields while working on the project, and we present its solutions and the futher studies on this matter of a project.