• Structural Engineering and Mechanics
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• v.10 no.2
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• pp.139-156
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• 2000

This paper concerns the development of a computational model for the damage evolution of engineering materials under dynamic loading. Two models describing the anisotropic damage evolution of a material are presented; the first is based on a power function of the effective equivalent stress and the second on the damage strain energy release rate. The methods for computing the damage accumulated in structural components and their implementation in a finite element programme are presented together with some numerical results. The dynamic response of a damaged structural component and the dynamic behaviour of a damaged material have been studied numerically. This study shows that the frequency spectrum of a damaged structure is down-shifted, while the damping ratio of damaged materials becomes higher, the amplitude of the response significantly increases and the resonance ensuing from the damage growth still occurs in a damaged structure.

• Nuclear Engineering and Technology
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• v.54 no.4
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• pp.1213-1220
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• 2022

The Emergency Diesel Generator (EDG) is a critical and essential part of the Nuclear Power Plant (NPP). Due to past catastrophic disasters, critical systems of NPP like EDG are designed to meet high dependability requirements. Therefore, we propose a framework for the dynamic reliability assessment using the Fault Tree and the Dynamic Bayesian Network. In this framework, the information of the component's failure probability is updated based on observed data. The framework is powerful to perform qualitative as well as quantitative analysis of the system. The validity of the framework is done by applying it on several NPP systems.

• Journal of Information Technology Services
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• v.5 no.2
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• pp.137-153
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• 2006

SOA(Service Oriented Architecture) can be a technique to make compassable software from mapping business service to software component. To support effective SOA, it is important that services have to be defined or classified more independently for dynamic and reusable composition. Several methods have been issued but no ways to defined service granularities, service type or service unit. In this paper we introduce 3 level views, service level, service granularity to reuse effectively. And, we suggest service definition guidelines using them.

• Communications for Statistical Applications and Methods
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• v.4 no.1
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• pp.119-128
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• 1997

Added variable plot and component-plus-residual plot are very useful for studying the role of a predictor in classical regression analysis. The former is usually used to check the effect of adding a new variable to existing model. The latter has been suggested as computationally convenient substitutes for the added variable plots, however, this plot is found to be better in detecting nonlinear relationships of a new predictor. By combining these two plots dynamically, we can take advantages of two plots simultaneously. And even further, we can get some knowledge of collinearity between a new predictor and predictors already in the model, and more accurate information about the possible outliers.

• Journal of the Korean Society of Safety
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• v.10 no.2
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• pp.24-31
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• 1995

This paper shows the fatigue durability test method for vehicle suspension systems. Durability should be assured for the safe driving during vehicle life cycle. A computer simulation for the vehicle dynamics was used to obtain dynamic loads that were required for the fatigue durability test. Durability tests were done for an Important load-carrying component of the suspension system. Stress analyses using stresscoat and strain gages were also done for the component. This study demonstrated an effective method for the fatigue durability test.

• Fashion & Textile Research Journal
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• v.14 no.4
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• pp.660-668
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• 2012

The purpose of this study is to analyze the thermal characteristics of garments marketed for Korean males and to investigate the influence of each garment on ensemble, by measuring their insulation values(clo) using thermal manikins. The results are as follows. The total insulations(clo) of ensembles for S/S seasons are between 1.46 and 2.6 clo, with the mean of 2.12 clo. The insulation in the still air condition is 1.23 clo, which means a decrease of 42% compared to the total insulation of all the component garments. The insulation of ensembles for S/S seasons in the dynamic air condition decreased by 46.8%, compared to the still air condition. The total insulation(clo) of ensembles for F/W seasons is between 3.84 and 7.36 clo with the mean of 4.74 clo. The insulation in the still air condition is 2.26 clo, which means a decrease of 53.6% compared to the total insulation of all the component garments. The insulation of ensembles for F/W seasons in the dynamic air condition decreased by 36.2%, compared to the still air condition. As the clo value of each component garment gets higher, the insulation of ensembles gets higher. Especially, the insulation of ensembles was more influenced by outer wear than inner wear. The insulation of ensembles could be predicted by the insulation of outerwear better.

• Journal of the Korean Institute of Gas
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• v.21 no.5
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• pp.89-94
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• 2017

The VR(Virtuality Reality) technology provides very close experience to reality by stimulating humans' external recognition with artificial technologies. In order to overcome the limitation of real-environment training, VR is being applied in industry field as a key technology to prevent safety accident and its control procedure training. However, it is difficult to build VR-based training system because 3D modeling and software coding are necessary for materialization of VR environment demands of many development resource. In this research referring to VR based training content implementation, a method to utilizing VRDC(VR-based Dynamic visualization Component) is suggested and by applying it to plant safety training system, it was confirmed its practicality.

• Journal of Advanced Navigation Technology
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• v.13 no.3
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• pp.419-425
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• 2009

The amount of incoming e-mails is increasing rapidly due to the wide usage of Internet. Therefore, it is more required to classify incoming e-mails efficiently and accurately. Currently, the e-mail classification techniques are focused on two way classification to filter spam mails from normal ones based mainly on Bayesian and Rule. The clustering method has been used for the multi-way classification of e-mails. But it has a disadvantage of low accuracy of classification and no category labels. The classification methods have a disadvantage of training and setting of category labels by user. In this paper, we propose a novel multi-way e-mail hierarchy classification method that uses PCA for automatic category generation and dynamic category hierarchy for high accuracy of classification. It classifies a huge amount of incoming e-mails automatically, efficiently, and accurately.

• Journal of the Korean Vacuum Society
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• v.15 no.4
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• pp.338-346
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• 2006

In semiconductor process, it is so hard to predict an exact failure point of the vacuum pump due to its harsh operation conditions and nonlinear properties, which may causes many problems, such as production of inferior goods or waste of unnecessary materials. Therefore it is very urgent and serious problem to develop diagnostic models which can monitor the operation conditions appropriately and recognize the failure point exactly, indicating when to replace the vacuum pump. In this study, many influencing factors are totally considered and eventually the monitoring model using multivariate statistical methods is suggested. The pivotal algorithms are Multiway Principal Component Analysis(MPCA), Dynamic Time Warping Algorithm(DTW Algorithm), etc.

• Progress in Medical Physics
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• v.9 no.2
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• pp.95-104
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• 1998

The dynamic properties of the 3rd-order neuron of the retina was investigated by using conventional intracellular recording techniques. Experiments were performed in the superfused retina-eyecup preparation of the channel catfish, Ictalurus punctatus. The cornea, iris, lens, and vitreous were removed by absorption with Kimwipe tissue under the dissection microscope thereby exposing the retina in a hemi -eyecup. The electrical signal was amplified by electrometer, viewed on oscilloscope. Regular signals from the cells were recorded on a penwriter and stored by data recorder and computer. Full-field, spot or annular light stimuli were generated on a computer monitor and focused onto the retina. Baclofen hyperpolarized the dark membrane potential, suppressed sustained component and enhanced transient component of the ON-sustained cell with a large transient component, but did not affect the surround antagonism of the cell. Baclofen selectively suppressed responses evoked by moving bar light stimuli on the ON-OFF transient cell. The results suggest that transient cells have directional selectivity in the inner retina. These dynamic properties of amacrine and ganglion cells were modulated by baclofen. Therefore, it is presumed that there is baclofen-induced directional selectivity in ON-OFF transient cells in the catfish retina.