• Journal of applied mathematics & informatics
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• v.13 no.1_2
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• pp.53-65
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• 2003

Here we present a study of small-amplitude, shallow water waves on sloping beds. The beds considered in this analysis are linear and quadratic in nature. First we start with stating the relevant governing equations and boundary conditions for the theory of water waves. Once the complete prescription of the water-wave problem is available based on some assumptions (like inviscid, irrotational flow), we normalize it by introducing a suitable set of non-dimensional variables and then we scale the variables with respect to the amplitude parameter. This helps us to characterize the various types of approximation. In the process, a summary of equations that represent different approximations of the water-wave problem is stated. All the relevant equations are presented in rectangular Cartesian coordinates. Then we derive the equations and boundary conditions for small-amplitude and shallow water waves. Two specific types of bed are considered for our calculations. One is a bed with constant slope and the other bed has a quadratic form of surface. These are solved by using separation of variables method.

• The Research Journal of the Costume Culture
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• v.18 no.6
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• pp.1112-1128
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• 2010

This study aims to know the trace of Korean musical, consider musical depending on its type, arrange characteristic of musical costume and find out the developmental direction of Korean musical costume with potentials as a culture industry. For study method, the data were collected from thesis, academic journal, book and internet web-site concerning musical costume, literatures were considered and performance costume photos, which were captured via musical performance site, were analyzed. The history of Korean modern-day musical is regarded as starting with (1966) in the full scale. Although foreign musical was imitated in 1970s~1980s, it may be called the growth period of Korean musical because the period showed the commercial possibility. Since 1990s, large-scaled musical securing good work and popularity was popular. In 2000s, musical industry was abundant quantitatively and qualitatively as investment or popularity was significantly expanded. The type of Korean musical are divided to opera musical of European, Broadway musical of American and creative musical of Korean. The costumes used in opera musical of European and Broadway musical of American are borrowed from original works through license or were manufactured in Korea by referring to the costumes of original works and using similar materials or fabrics. The costumes used in creative musical of Korea are designed by either domestic or foreign designers and produced in Korea.

• Journal of the Korean Society of Food Culture
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• v.10 no.5
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• pp.475-483
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• 1995

This study was undertaken to determine factors associated with infant feeding practices among highly educated Korean mothers living in Texas, USA and local populations. In both groups, infant's birth order, maternal age, prenatal education, husband's attitude, mother's attitude and infant's taking a bottle to bed were not associated with infant's feeding patterns significantly. However, there was a significant difference in initiating time for introduction of supplementary foods between Koreans and Americans. Thus Korean mothers introduced supplementary foods earlier than American counterparts. Furthermore the infant's feeding method among all participants affected the time for introducing supplementary foods significantly. Though attitude of Korean mothers toward breastfeeding was slightly more positive than that of American mothers, the prevalence of exclusive breastfeeding in Koreans was much lower than that in Americans. It might be suggested that effective nutrition education program for Korean subjects should be developed to practice breastfeeding from positive attitude and knowledge. It might be also suggested that participation of prenatal nutrition education involving fathers should be encouraged for promotion of rates of initiation and duration of exclusive breastfeeding of mothers.

• Journal of Korean Elementary Science Education
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• v.19 no.1
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• pp.57-69
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• 2000

The purpose of this study was to seek desirable direction of science teaching and to present meaningful ideas for implementing the science curriculum and teaching materials by measuring the degree of the students' understandings on science and comparing it with those of American students. The researcher comprised 790 primary and middle school students for the study and administered them questionnaires developed by Trowbridge, Bybee, and Sund. The questionnaires were analyzed along with three categories such as science method, science theory, and the achievement of scientists. The researcher used t-test and ANOVA in order to compare the difference of their understandings in accordance with grades and gender, and later compared Korean students' understandings with those of similar aged American students administered by the National Assessment of Educational Progress (NAEP) The research loathed to the overall conclusions as follows; Both primary and middle school students' understandings on science revealed positive and appeared no significant difference in gender. And it is thought that science education was being carried out hopefully to enhancing Korean students' scientific literacy, therefore, science teaching like what is implemented to the classrooms currently should be kept on in future. On the other hand, it is necessary to change primary school children's understandings on attitude and value of scientists while to change middle school students' understandings on scientific processes by experiment. Also primary school children need to understand that scientists are willing to change their ideas when new information becomes known.

• Journal of Science Education
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• v.34 no.2
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• pp.421-431
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• 2010

The purpose of this study was to identify instructional components supporting students' interest and creativity in American middle school science classrooms. Two 7th grade classrooms were selected, and observed for 11 class periods each. Results showed that hands-on and small group activities were the most effective ways to increase students' interest. The teachers' instructional approaches, such as individualized paced teaching, sufficient peer teaching, permissive atmosphere, various media, and purpose-focused summary game were found to influence students' interest. To enhance students' creativity, increasing interest, making hypothesis, and trying to various experimental method with sufficient time were identified as effective components.

• Structural Engineering and Mechanics
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• v.22 no.5
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• pp.631-645
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• 2006

Buckling capacity of compression members may change due to inadvertent changes in the member section dimensions or material properties. This may be the result of repair, modification of section properties or degradation of the material properties. In some occasions, enhancement of buckling capacity of compression members may be achieved through splicing of plates or utilization of composite materials. It is very important for a designer to predict the buckling resistance of the compression member and the important parameters that affect its buckling strength once changes in section and/or material properties took place. This paper presents an analytical approach for determining the buckling capacity of a compression member whose geometric and/or material properties has been altered resulting in a multi-step non-uniform section. This analytical solution accommodates the changes and modifications to the material and/or section properties of the compression member due to the factors mentioned. The analytical solution provides adequate information and a methodology that is useful during the design stage as well as the repair stage of compression members. Three case studies are presented to show that the proposed analytical solution is an efficient method for predicting the buckling strength of compression members that their section and/or material properties have been altered due to splicing, coping, notching, ducting and corrosion.

• Proceedings of the Ginseng society Conference
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• 1978.09a
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• pp.55-66
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• 1978

Five ginsenosides $(A_1,\;A_2,\;B_1,\;B_2,\;C)$ and a yellow pigment were isolated from American ginseng stems and leaves. Ginsenoside $A_2,\;B_1,\;B_2$ and C were proven to be identical with Korean ginseng root ginsenoside $Rg_1,$ Rd, Re and $Rb_2,$ respectively. The yellow pigment proved identical with panasenoside isolated from Korean ginseng leaves. Ginsenoside $A_1$, which was also present in American ginseng roots, was not identical to any of the known root (ginsenoside $R_{0}-Rg_{2}$) and leaf (ginsenoside $F_{1}-F_{3}$) Korean ginseng saponins. A gas-liquid chromatographic method was developed to analyze ginsenosides and sapogenins in rabbit plasma and urine samples. Panasenoside and stigmasterol were found to be the best internal standards for ginsenosides and sapogenihs, respectively. Ginsenoside C had a significantly longer half-life, higher plasma protein binding, lower metabolic and renal clearance than ginsenoside $A_1,\;A_2\;and\;B_2$. Ginsenosides were not found in rabbit plasma and urine samples after oral administration. Ginsenoside C had a higher toxicity than ginsenoside $A_2$ after intraperitoneal administration to mice. Toxicity was not observed after oral administration of the ginsenosides.

• Nuclear Engineering and Technology
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• v.34 no.3
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• pp.259-267
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• 2002

NFPA-803 has been referred as the Fire Protection Standard at the Nuclear Power Plants of Pressurized Water Reactor. This Standard has been used as the fire protection regulation, containing prescriptive requirements with deterministic methodology. Recently, with cumulative efforts by the U.S. Nuclear Regulatory Commission and Utilities in America to establish a new Standard, including a quantitative evaluation methodology, NFPA-805, the Performance-Based Standard for FIRE Protection for Light Water Reactor Electric Generating Plants was issued and approved by the American National Standards Institute as an American National Standard with an effective date of February 9, 2001. This paper presents an analysis result from the computer modeling for the fire simulation In addition, it proposes the idea that this kind of analytic method can be available for the facilities design of fire prevention and protection fields, as well as an evaluation for the fire suppression system with a quantitative analysis for the thermal phenomena in fire compartments in Nuclear Power Plants.

• Steel and Composite Structures
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• v.7 no.4
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• pp.321-337
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• 2007

The investigation on the behaviour of cold-formed stainless steel non-slender circular hollow section columns is presented in this paper. The normal strength austenitic stainless steel type 304 and the high strength duplex materials (austenitic-ferritic approximately equivalent to EN 1.4462 and UNS S31803) were considered in this study. The finite element method has been used to carry out the investigation. The columns were compressed between fixed ends at different column lengths. The geometric and material nonlinearities have been included in the finite element analysis. The column strengths and failure modes were predicted. An extensive parametric study was carried out to study the effects of normal and high strength materials on cold-formed stainless steel non-slender circular hollow section columns. The column strengths predicted from the finite element analysis were compared with the design strengths calculated using the American Specification, Australian/New Zealand Standard and European Code for cold-formed stainless steel structures. The numerical results showed that the design rules specified in the American, Australian/New Zealand and European specifications are generally unconservative for the cold-formed stainless steel non-slender circular hollow section columns of normal and high strength materials, except for the short columns and some of the high strength stainless steel columns. Therefore, different values of the imperfection factor and limiting slenderness in the European Code design rules were proposed for cold-formed stainless steel non-slender circular hollow section columns.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.10
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• pp.1728-1737
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• 2001

1760년대 말의 미국문화는 전통적인 가치관에 반발하는 청년문화운동의 화산으로 특징지을 수 있는데 이러한 사회적인 변화는 복식에 새롭고 혁신적인 스타일을 가져오게 되는 요인이 되었다. 특히 이 시기의 미국의 청년층에 의해 일어난 반문화적인 현상으로 인식되어 온 동앙문화의 도입은 미국의 여성복식에 tie-dyeing(홀치기염)패션의 출현으로 복식에 반영되었다. 이에, 본 연구는 지금까지 복식 학자들에 의한 단편적인 추론으로만 설명되어 왔던 1960년대 말 미국여성복식에 나타난 홀치기염 패션의 특성에 관하여 문화적인 배경에 관한 고찰과 함께 이 시기에 출판된 정기 간행물을 연구의 일차자료로 이용하여 실증적으로 분석하는 데 그 목적이 있다. 연구방법으로는 1955년부터 1975년 사이에 출판된 Vogue와 Mademoiselle 잡지에 실린 홀치기염 패션 사진자료를 내용분석법을 이용하여 수집하여 의류품목, 소재, 기법, 디자이너 및 제조업 체에 관한 내용으로 나누어 분석하였다. 연구 결과, 두 종류의 잡지 모두에서 다양한 소재로 만들어진 여러 의류품목에 각종 기법으로 적용되었던 홀치기염 패션이 이 시기에 나타나, 청년층에서 시작되었던 이 패션이 미국의 대중 및 상류층의 복식에도 확산되었음이 밝혀졌다. 나아가 홀치기염 패션스타일이 가장 많이 보여졌던 1969년에서 1971년 사이의 기간은 청년층의 반문화적 현상이 절정을 이루었던 시기와 일치하고 있어서 이러한 급진적인 사회 현상이 그대로 패션에도 반영되고 있음을 알 수 있었다.