• Journal of the Society of Naval Architects of Korea
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• v.29 no.4
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• pp.1-6
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• 1992

The finite difference simulation method for ship waves is introduced for hull form improvement. Numerical simulations were performed for a series of modified hull forms and the simulated results were used for the determination of the better hull forms. A 4,400 TEU container carrier which was designed and experimented in towing tank was chosen for the purpose. The calculation results are compared with those of model test, of simplified Neumann-kelvin problems and of Rankine source method. In this study, it is shown that the combination of the computer simulation by our method with the experiment provides one of the most economical and reliable procedures of hull form improvement and that the degree of accuracy of this method is so high that it can cope with very practical design purposes.

• Journal of KIISE
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• v.42 no.12
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• pp.1561-1567
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• 2015

Abstract Semi-supervised learning is an area in machine learning that employs both labeled and unlabeled data in order to train a model and has the potential to improve prediction performance compared to supervised learning. Graph-based semi-supervised learning has recently come into focus with two phases: graph construction, which converts the input data into a graph, and label inference, which predicts the appropriate labels for unlabeled data using the constructed graph. The inference is based on the smoothness assumption feature of semi-supervised learning. In this study, we propose an enhanced label inference algorithm by incorporating the importance of each vertex. In addition, we prove the convergence of the suggested algorithm and verify its excellence.

• Journal of the Korean Institute of Telematics and Electronics
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• v.18 no.5
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• pp.35-45
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• 1981

An asymptotic solution of electromagnetic waves scattered by a right-angled dielectric wedge for plane wave incidence is obtained. Scattered fields are constructed by waves reflected and refracted from dielectric interfaces (geometric-optical fields) and a cylindrical wave diffracted from the edge. The edge diffracted field is obtained by adding a correction to the edge diffraction of physical optics approximation, where the correction field is calculated by solving a dual series equation amenable to simple numerical calculation. Validity of this result is assured by two limits of relative dielectric constant $\varepsilon$ of the wedge. The total asymptotic field calculated results in a Rawlins' Neumann series solution for small $\varepsilon$, and the edge diffraction pattern is shown to approach that of a perfectly conducting wedge for large $\varepsilon$. Calculated field patterns are presented and the accuracy of physical optics approximation is discussed.