• Applied Microscopy
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• v.37 no.2
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• pp.123-133
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• 2007

The strain fields due to precipitates, especially S-phase $(Al_2CuMg)$ particles in Al-2.5Cu-1.5Mg wt.% alloy were first investigated with Large Angle Convergent Beam Electron Diffraction (LACBED) method. The work involves LACBED pattern simulations to estimate possibly the strength of the strain fields. To do this the morphology of S-particle was optimized as a cylindrical shape with $a_s$ axis, and the displacement vector of strain fields was assumed to be perpendicular to $a_s$ axis. With this simple model the reasonable fittings between the observed patterns of the strain fields and simulations were obtained. And in the early aging stage of the alloy the significant strain fields were not observed. As a result of this study it is expected that the strain fields due to S-phase precipitates in the stage with maximum hardness would make a complex networks to possibly contribute to hardiness of the alloy.

• Wind and Structures
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• v.37 no.3
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• pp.179-189
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• 2023

Multiple studies conducted in the past evaluated the conductor response under one tornado wind field, while the performance of transmission lines under different tornado wind fields still remains unknown. Thus, the objective of this paper is to estimate the variation in the conductor's critical longitudinal and transverse reactions under different tornado wind fields, as well as providing the corresponding critical tornado configurations. The considered full-scale tornadoes are the Spencer, South Dakota, 1998, the Stockton, Kansas, 2005 and the Goshen County, Wyoming, 2009. Computational Fluid Dynamics (CFD) simulations were previously conducted to develop these wind fields. All tornadoes have been rescaled to have a common velocity matching the upper limit of the F2 Fujita scale. Eight conductor systems, each including six spans, are considered in this paper. For each conductor, parametric studies are conducted by varying the location of the three tornado wind fields relative to the tower of interest, therefore the peak reactions associated with each tornado are determined. A semi-analytical closed-form solution, previously developed and validated, is used to calculate the reactions. The study conducted in this paper can be divided into two parts: In the first part, a parametric study considering a wide range of tornado locations is conducted. In the second part, the parametric study focuses on the tornado location leading to the critical tangential velocity on the tower. Based on this extensive parametric study, a critical tornado defined as the Design Tornado and its critical locations, tornado distance R = 125 m, tornado angle 𝜃 = 15° and 30°, are recommended for design purposes.

• The Research Journal of the Costume Culture
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• v.8 no.6
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• pp.853-863
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• 2000

This study is planned to present the future direction of the study of Korean clothes through the realistic recognition of the changes of studying issues of each area of the related clothes. For this purpose, the writer of this thesis have collected, classified and analyzed those various kinds of papers and theses published in the professional magazines of clothes such as Journal of Korean Home Economics, Journal of the Korean Society of Clothing and Textiles, Journal of the Korean Society of Costume, The Research Journal of the Costume Culture so that I might examine and study the main trend of the related study. The result of the study is as follows. 1. Since the first publication of Journal of Korean Home Economics in 1959 and Journal of the Korea Society of Clothing and Textiles, and Journal of the Korean Society of Costume, the study of clothes has been gradually increased. Furthermore, since 1990 the issuing times of various kinds of Journals have been continuously increased with the foundation of The Research Journal of the Costume Culture and Journal of Fashion Business. 2. Theses and papers published in the four greatest Journals of Korean Clothing and Textiles have been studies for the detailed classification and analysis of the data. According to the study, It is found that the theses in Journal of the Korea Society of Clothing and Textiles have actively studied textiles as they had studied before 1990s and those in Journal of the Korean Society of Costume have studied history of costumes and those in The Research Journal of the Costume Culture have studied the composition and science of clothes. 3. The order of studying subjects was 1) Design and Aesthetics, 2) Fashion Merchandising 3) Textiles, 4) Clothing Construction, 5) History of Costumes, 6) Costume Culture, 7) Socio-Psychology of clothing, 8) Others. Considering the above mentioned result of the study, most of the main fields of the clothing and textiles study have been studied continuously in balance since 1990 unlike the past although the past studies had been performed largely in some main fields only. And it was found that fields of clothing styles and clothing goods have been studied most actively since 1990s. 4. The studying field of Design and Aesthetics has showed to have the trend to be studied very actively since 1990s, which has utilized various relevant data with scholastic approach to psychology and aesthetics. Regarding Fashion Merchandising, the study of consumers decision process has been performed most actively. And theses on the international trades have been published considerably more than ever before, which resulted in gradual increase in gradual increase in the study of the fields related with global marketing, internet marketing, textile products exports, and overseas brands, etc. Regarding Textiles, the field of clothing sanitation and management has been studied more actively than that of clothing materials. In case of clothing construction, the study of physical styles and pattern making has been more active than the other related fields. Fields of socio-psychology of clothing and history costume have been a little reduced. Field of costume culture has been firmly rooted as an independent subject to be studied in the clothing related study. And study of the clothes has shown various trends of studies of ethnic & folk clothes, religious and ceremonial garments, linguistic & favorite approach to clothes and academic analysis of the data.

• Journal of the Korean Society for Library and Information Science
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• v.33 no.1
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• pp.87-111
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• 1999

This article investigates the functions, needs, and developments of the MARC format for classification data. and recommends the development for the KORMARC format for classification data. It ae analyzes the record structure, content designation and the content of it mainly based on USMARC format. Structure and content designation are almost same with those of the bibliographic and authority formats. The data fields divided into functional blocks based on their functions. Record contents of the data in the fixed-length fields include more elements on the classification numbers, including type of number, classification validity, standard or optional number, synthesized number. Variable fields can be grouped into several blocks, inducing those for numbers and codes: for classification numbers and terms; for references and tracings; for notes fields: for index terms fields, and for number building fields. Data in each fields of this format have the same contents with those in other related fields as soon as possible. This article analyzes the content in each data fields in detail.

• Journal of The Korean Astronomical Society
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• v.32 no.1
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• pp.65-73
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• 1999

In this study we present a new improved nonlinear calibration method for vector magnetograms made by the Solar Flare Telescope of BOAO. To identify Fe I 6302.5 line, we have scanned monochromatic images of the line integrated over filter passband, changing the location of the central transmission wavelength of a Lyot filter. Then we obtained a filter-convolved line profile, which is in good agreement with spectral atlas data provided by the Sacramento Peak Solar Observatory. The line profile has been used to derive calibration coefficients of longitudinal and transverse fields, employing the conventional line slope method under the weak field approximation. Our improved nonlinear calibration method has also been used to calculate theoretical Stokes polarization signals with various angles of inclination of magnetic fields. For its numerical test, we have compared input magnetic fields with the calibrated ones, which have been derived from the new improved non-linear method and the conventional method respectively. The numerical test shows that the calibrated fields obtained from the improved method are consistent with the input fields, but not with those from the conventional method. Finally, we applied our new improved method to a dipole model which characterizes a typical field configuration of a single, round sunspot. It is noted that the conventional method remarkably underestimates the transverse field component near the inner penumbra.

• Journal of the Chungcheong Mathematical Society
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• v.27 no.2
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• pp.183-203
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• 2014

We examine fundamental units of quadratic function fields from continued fraction of $\sqrt{D}$. As a consequence, we give another proof of geometric analog of Ankeny-Artin-Chowla-Mordell conjecture and bounds for class number, and study real quadratic function fields of minimal type with quasi-period 4.

• Journal of the Korean Mathematical Society
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• v.43 no.1
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• pp.133-145
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• 2006

We study Riemannian or pseudo-Riemannian manifolds which admit a closed conformal vector field. Subject to the condition that at each point $p{\in}M^n$ the set of conformal gradient vector fields spans a non-degenerate subspace of TpM, using a warped product structure theorem we give a complete description of the space of conformal vector fields on arbitrary non-Ricci flat Einstein spaces.

• Journal of the Korean Mathematical Society
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• v.42 no.3
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• pp.471-484
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• 2005

We study Riemannian or pseudo-Riemannian manifolds which carry the space of closed conformal vector fields of at least 2-dimension. Subject to the condition that at each point the set of closed conformal vector fields spans a non-degenerate subspace of the tangent space at the point, we prove a global and a local classification theorems for such manifolds.

• Honam Mathematical Journal
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• v.40 no.2
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• pp.265-280
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• 2018

In this study, we firstly define equations of motion based on the traditional model Newtonian mechanics in terms of the Frenet frame adapted to the trajectory of the moving particle in Lie groups. Then, we compute energy on the moving particle in resultant force field by using geometrical description of the curvature and torsion of the trajectory belonging to the particle. We also investigate the relation between energy on the moving particle in different force fields and energy on the particle in Frenet vector fields.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.924-925
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• 2014

This paper present a method of GRM constant generation in case of prime number P=3 over finite fields. Also we discuss the method which is the optimal GRM generation compare with polarity. The proposed method is the efficiency and optimization compare with earlier method.