• Journal of Advanced Navigation Technology
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• v.14 no.6
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• pp.900-908
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• 2010

Recently, OOM(Object-Oriented Method) access method which begins to apply to software development is emphasizing development cost and time reduction through independent software reuse. But because of planning to the exclusion of the lack of knowledge and expansion or performance for development technology many problems are coming out. Therefore, this thesis suggests Effective Object-Oriented Modeling methods considering the plan for higher productivity enhancement of software in the software development life cycle. Effective Object-Oriented Modeling method includes, methods, Use Case modeling methods, Analysis Modeling methods, Design Modeling methods and others.

• Nuclear Engineering and Technology
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• v.40 no.5
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• pp.375-386
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• 2008

Conventional static reliability analysis methods are inadequate for modeling dynamic interactions between components of a system. Various techniques such as dynamic fault tree, dynamic Bayesian networks, and dynamic reliability block diagrams have been proposed for modeling dynamic systems based on improvement of the conventional modeling methods. In this paper, we review these methods briefly and introduce dynamic nodes to the existing reliability graph with general gates (RGGG) as an intuitive modeling method to model dynamic systems. For a quantitative analysis, we use a discrete-time method to convert an RGGG to an equivalent Bayesian network and develop a software tool for generation of probability tables.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.10
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• pp.718-723
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• 2012

The purpose of this study is to propose modeling method of Underfloor Air Distribution System with reliability and validity by comparing characteristics of modeling methods. For this, the modeling methods of UFAD were selected by investigating various modeling methods of previous researches. Then, simulations were conducted by using EnergyPlus which is dynamic analysis program of building energy. Annual energy consumption for each method was compared with a wide range of indoor thermal loads. As a result, the methodology of reducing internal gains can cause under sizing of the system. It suggests modeling methods to reflect occupied zone air-conditioning, temperature stratification and supply plenum which are the main characteristics of UFAD.

• Smart Structures and Systems
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• v.19 no.1
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• pp.67-90
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• 2017

The interdisciplinary research area of small scale energy harvesting has attracted tremendous interests in the past decades, with a goal of ultimately realizing self-powered electronic systems. Among the various available ambient energy sources which can be converted into electricity, wind energy is a most promising and ubiquitous source in both outdoor and indoor environments. Significant research outcomes have been produced on small scale wind energy harvesting in the literature, mostly based on piezoelectric conversion. Especially, modeling methods of wind energy harvesting techniques plays a greatly important role in accurate performance evaluations as well as efficient parameter optimizations. The purpose of this paper is to present a guideline on the modeling methods of small-scale wind energy harvesters. The mechanisms and characteristics of different types of aeroelastic instabilities are presented first, including the vortex-induced vibration, galloping, flutter, wake galloping and turbulence-induced vibration. Next, the modeling methods are reviewed in detail, which are classified into three categories: the mathematical modeling method, the equivalent circuit modeling method, and the computational fluid dynamics (CFD) method. This paper aims to provide useful guidance to researchers from various disciplines when they want to develop and model a multi-way coupled wind piezoelectric energy harvester.

• Journal of the Korean Society of Safety
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• v.14 no.4
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• pp.93-99
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• 1999

A try was carried out to reduce lead time of die manufacturing. That is to make manual machining and finishing work time shorter by improving CAD/CAM modeling methods, so called with "separate modeling" and "relief modeling". The manual machining and finishing manual work time were reduced adapting the novel CAD/CAM modeling methods. Ultimately we accomplished much reduction of the lead time of die manufacturing.f die manufacturing.

• Journal of the Society of Naval Architects of Korea
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• v.33 no.1
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• pp.173-181
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• 1996

In this paper, we studied the modeling methods of initial ship structure design results using ship structure product model for concurrent engineering in shipbuilding industry. We suggested two modeling methods which are programming method using CAD commands and Macros for primary structure members. Also, we investigated three modeling procedures which are modeling procedure in unit concept, modeling procedure using version control, and modeling procedure for computer aided process planning. We demonstrated how to use the structure product modeling results in some application fields. Finally, we proposed some ideas for future research.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1678-1689
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• 2008

Recently, OOM(Object-Oriented Method) access method which begins to apply to software development is emphasizing development cost and time reduction through independent software reuse. But because of planning to the exclusion of the lack of knowledge and expansion or performance for development technology many problems are coming out. Therefore, this thesis suggests Effective Object-Oriented Modeling methods considering the plan for higher productivity enhancement of software in the software development life cycle. Effective Object-Oriented Modeling method includes, methods, Use Case modeling methods, Analysis Modeling methods, Design Modeling methods and others. This thesis suggests Framework model method read in characteristics as follows. First, suggestion about effective object-oriented standard model development, Second, retrenchment of software development or maintenance cost, Third, solution about uncertain problems of projects in line with the application of new technology.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.645-652
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• 2016

The statistical modeling of input random variables is necessary in reliability analysis, reliability-based design optimization, and statistical validation and calibration of analysis models of mechanical systems. In statistical modeling methods, there are the Akaike Information Criterion (AIC), AIC correction (AICc), Bayesian Information Criterion, Maximum Likelihood Estimation (MLE), and Bayesian method. Those methods basically select the best fitted distribution among candidate models by calculating their likelihood function values from a given data set. The number of data or parameters in some methods are considered to identify the distribution types. On the other hand, the engineers in a real field have difficulties in selecting the statistical modeling method to obtain a statistical model of the experimental data because of a lack of knowledge of those methods. In this study, commonly used statistical modeling methods were compared using statistical simulation tests. Their advantages and disadvantages were then analyzed. In the simulation tests, various types of distribution were assumed as populations and the samples were generated randomly from them with different sample sizes. Real engineering data were used to verify each statistical modeling method.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.494-498
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• 1996

Three fuzzy input space partitoining methods, which are grid, tree, and scatter method, are mainly used until now. These partition methods represent good performance in the modeling of the linear system and nonlinear system with independent modeling variables. But in the case of the nonlinear system with the coupled modeling variables, there should be many fuzzy rules for acquiring the exact fuzzy model. In this paper, it shows that the fuzzy model is acquired using transformed modeling vector by linear transformation of the modeling vector.

• Journal of the Ergonomics Society of Korea
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• v.25 no.2
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• pp.161-172
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• 2006

This study aims to compare and contrast the Kansei modeling methods for building a luxuriousness model that people feel about appearance of mobile phones. For the evaluation based on Kansei engineering approaches, 15 participants were employed to evaluate 18 mobile phones using a questionnaire. The results of evaluation were analyzed to build luxuriousness models through quantification I method, neural network, and decision tree method, respectively. The performance of Kansei modeling methods was compared and contrasted in terms of accuracy and predictability. The result of comparison of modeling methods indicated that model accuracy and predictability was closely related to the number of variables and data size. It was also revealed that quantification I method was the best in terms of model accuracy while decision tree method was the best modeling method with small variance in terms of predictability. However, it was empirically found that quantification I method showed extremely unstable predictability with small number of data. Consequently, it is expected that the research findings of this study might be utilized as a guideline for selecting proper Kansei modeling method.