• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.5
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• pp.462-475
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• 1997

In this paper, the accurate characterization of the input impedance of a rectangular waveguide with a conducting post and the other discontinuity is presented using mode matching method and the equivalent transmission line theory. By the proposed method, the input impedance of rectangular waveguide with a conducting post and the other discontinuity as a function of the radius and height of the post, the reflection coefficient of the other discontinuity, and the distance between the post and the other discontinuity is calculated. The simulated result shows good agreement with the experimental result by Marcuvitz.

• Journal of the Korean Society of Costume
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• v.56 no.9 s.109
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• pp.1-13
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• 2006

The purpose of this study is to apply a concept of open structure to clothing design and to verify the characteristics found in the various types of clothing which has open structure. The literatures from various academic fields including philosophy, literature, social science, architecture, and fine arts are investigated to define the concept of openness and to analyze it from the perspectives both of the visual and of the moaning of openness. This paper is to identify the types and the characteristics of clothing by future intention, complexity, discontinuity of open structure. By closely examining fashion design after 1980s found in fashion collection publications and designer's websites, the results of this study are as follows: first, the concept of openness can be classified into two different levels, that is, visual and meaning, secondly, in clothing the concept of open structure is applied to the meaning side by future intention, by complexity and by discontinuity. Open structure through future Intention has new content and interpretation and must have the possibility of intelligence awakening, future guidance and basic contents. Open structure through complexity has secondary function exists concurrent with the shape key example is the smart clothes with the digital functions. It has functions of amusement, supplement and protective, and is future clothes which satisfies with health, welfare, desire of beauty. Open structure with discontinuity is clothes with dramatic changes in system, structures and states. Structure can be changed by silhouette, detail, or fabric, material, or dramatic and practical function as tools in terms of productions and environment. This study can help to formulate and to integrate the concept of open structure in clothing with various phases and enhance the value of clothes by showing an application of the concept of openness to the clothing in meaning level.

• Proceedings of the Korean Statistical Society Conference
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• 2002.11a
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• pp.103-108
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• 2002

We consider an estimation of discontinuous variance function in nonparametric heteroscedastic random design regression model. We first propose estimators of a change point and jump size in variance function and then construct an estimator of entire variance function. We examine the rates of convergence of these estimators and give results on their asymptotics. Numerical work reveals that the effectiveness of change point analysis in variance function estimation is quite significant.

• Journal of the Korean Statistical Society
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• v.35 no.1
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• pp.1-23
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• 2006

In this paper we consider an estimation of the discontinuous variance function in nonparametric heteroscedastic random design regression model. We first propose estimators of the change point in the variance function and then construct an estimator of the entire variance function. We examine the rates of convergence of these estimators and give results for their asymptotics. Numerical work reveals that using the proposed change point analysis in the variance function estimation is quite effective.

• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.32-36
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• 2002

This paper presents the results of wave profile detection from video image using the Mexican hat function. The Mexican hat function has been extensively used in the field of signal processing to detect discontinuity in the images. The analysis was done on the numerical image and video images of waves that were taken in the small wave flume. The results show that the Mexican hat function is an excellent tool for wave profile detection.

• The Pure and Applied Mathematics
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• v.21 no.4
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• pp.271-279
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• 2014

Let $T_l$ be a transformation on the interval [-1, 1] defined by Chebyshev polynomial of degree $l(l{\geq}2)$, i.e., $T_l(cos{\theta})=cos(l{\theta})$. In this paper, we consider $T_l$ as a measure preserving transformation on [-1, 1] with an invariant measure $\frac{1}{\sqrt[\pi]{1-x^2}}dx$. We show that If f(x) is a nonconstant step function with finite k-discontinuity points with k < l-1, then it satisfies the Central Limit Theorem. We also give an explicit method how to check whether it satisfies the Central Limit Theorem or not in the cases of general step functions with finite discontinuity points.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.365-372
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• 2006

A new meshfree formulation is developed for material discontinuity problems. A local interfacial jump function which is defined as hyperplane function is embedded in the meshless approximation and the approximation accurately models functions with jumps in the displacement and the derivative fields. Diffuse derivative technique copes with difficulty due to complexity of derivative computation of meshfree approximation. Collocation method with diffuse derivative accelerates computing speed for numerical solution. By solving inclusion and composite material problems, the robustness and effectiveness of the method are verified.

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.4 s.15
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• pp.43-54
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• 2004

The broadband receiver functions are developed from teleseismic P waveforms recorded at Wonju(KSRS), Inchon(IRIS), and Pohang(PHN), and are analyzed to examine the crustal structure beneath these stations. The teleseismic receiver functions are inverted in the time domain of the vertical P wave velocity structures beneath the stations. Clear P-to-S converted phases from the Moho interface are observed in teleseismic seismograms recorded at these stations. The crustal velocity structures beneath the stations are estimated by using the receiver function inversion method(Ammon et al., 1990). The general features of inversion results are as follows: (1) For the Inchon station, the Conrad discontinuity exists at 17.5 Km(SW) deep and the Moho discontinuity exists at 29.5 Km(NW) and 30.5 Km(SE, SW) deep. (2) The shallow crustal structure beneath Wonju station may be covered with a sedimentary rock of a 3 Km thickness. The average Moho depth is assumed about 33.0 Km, and the Conrad discontinuity may exist at 17.0 Km(NE) and 21.0 Km(NW) deep. (3) For Pohang station, the thickness of shallow sedimentary layer is a 3.0 Km in the direction of NE and NW. The Moho depth is 28.0 Km in the direction of the NE and NW. The Conrad discontinuity can be estimated to be existed at 21.0 Km deep for the NE and NW directions.

• Journal of Korea Trade
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• v.23 no.5
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• pp.27-44
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• 2019

Purpose - The purpose of this paper is to analyze the net effect of the green total factor productivity (GTFP) of China's manufacturing industry from the China-Korea Free Trade Area (China-Korea FTA) quantitatively. Design/methodology - Firstly, the Global Malmquist-Luenberger (GML) index based on the SBM directional distance function is used to measure the GTFP of China's manufacturing and analyze the driving force for its growth. Secondly, the regression discontinuity quantitative analysis is used to determine the impact of the China-Korea FTA on China's manufacturing GTFP. Findings - Our main findings can be summarized as follows: the China-Korea FTA has promoted the GTFP of China's manufacturing with an effect evaluation mainly resulting from green technology progress. And there is industry heterogeneity in the policy effect on the manufacturing GTFP due to the China-Korea FTA. Namely, policy promotion from the China-Korea FTA is more effective on the GTFP of equipment manufacturing than it is on those of other industries. Originality/value - First, an evaluation and analysis of the GTFP development of China's manufacturing that employs GML index based on SBM directional distance function. Second, a quantitative estimate of China-Korea FTA's net effect on China's manufacturing industrial GTFP that uses regression discontinuity analysis, which is considered to be the closest method to natural experiments and superior to other causal inference methods. Third, an in-depth discussion of the practical steps that China's manufacturing can take to improve GTFP development and integrate China-Korea FTA construction into economic development.

• Journal of the Korean Data and Information Science Society
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• v.23 no.4
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• pp.765-775
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• 2012

The cross-validation is a popular method to select bandwidth in all types of kernel estimation. The maximum likelihood cross-validation, the least squares cross-validation and biased cross-validation have been proposed for bandwidth selection in kernel density estimation. In the case that the probability density function has a discontinuity point, Huh (2012) proposed a method of bandwidth selection using the maximum likelihood cross-validation. In this paper, two forms of cross-validation with the one-sided kernel function are proposed for bandwidth selection to estimate the location and jump size of the discontinuity point of density. These methods are motivated by the least squares cross-validation and the biased cross-validation. By simulated examples, the finite sample performances of two proposed methods with the one of Huh (2012) are compared.