• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.11
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• pp.983-989
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• 2007

The bird strike simulation is a problem characterized by a high degree of uncertainty. It deals with nonlinear dynamics, complicated models of bird materials and geometry, as well as a plenty of possible boundary and initial conditions. In this complex field, uncertainty management plays an important role. This paper aims to assess the effect of input uncertainty of bird strike analysis on the impact behavior of the leading edge of the WIG(Wing in Ground Effect) craft obtained with finite element analysis using LS-DYNA 3D. The uncertainties of the bird strike simulation arise due to imprecision or lack of information, due to variability or scatter, or as a consequence of model simplification. These uncertain parameters are represented by fuzzy numbers with their membership functions quantifying an initial guess for the actual value of the model parameter. Using the transformation method as a special implementation of fuzzy arithmetic, the model can be analyzed with the intention of determining the influence of each uncertain parameter on the overall bird strike behavior.

• Composites Research
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• v.19 no.5
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• pp.12-19
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• 2006

In this paper, conceptual structural design of the main wing for a small scale WIG(Wing in Ground Effect) among high speed ship projects, which will be a high speed maritime transportation system for the next generation in Rep. of Korea, was performed. The Carbon/Epoxy material was selected for the major structure, and the skin-spar with a foam sandwich structural type was adopted for improvement of lightness and structural stability. As a design procedure for the present study, firstly the design load was estimated through the critical flight load case study, and then flanges of the front and rear spars from major bending loads and the skin and the spar webs from shear loads were preliminarily sized using the netting rule and the rule of mixture. Stress analysis was performed by a commercial FEA code, NASTRAN. From the stress analysis results for the first designed wing structure, it was confirmed that the upper skin between the front spar and the rear spar was unstable fer the buckling. Therefore in order to solve this problem, a middle spar and the foam sandwich type structure at the skin and the web were added. After design modification, the structural safety and stability for the final design feature was confirmed. In addition to this, the insert bolt type structure with eight high strength bolts to fix the wing structure to the fuselage was adopted for easy assembly and removal as well as in consideration of more than 20 years fatigue life.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.43.2-43.2
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• 2005

• Bulletin of the Society of Naval Architects of Korea
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• v.37 no.2
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• pp.37-63
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• 2000

본 연구는 대전 계롱대에서 개최된 '99 조함 세미나에서 발표된 내용이다. 해면효과익선의 특성, 발전배경, 경제성 및 문제점등에 대해서 언금하고 한국해군력 증강 활용방안에 대해서 언급하였다. 원고의 내용순서는 다음과 같다.

• Fashion & Textile Research Journal
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• v.5 no.1
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• pp.25-33
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• 2003

Rococo, which is represented as immoderate pleasure and luxurious aristocratism, had required to be liberal and unconventional in art and life, and the hairstyles were also much more fantastic, huge, and splendid than ever. Women's hairstyles in the early 18th century were the relatively simple style of Pompadour style that didn't inflate hairs and combed them backward. Then, as changes in haristyles began to appear in around 1760, the styles became gradually higher and huger, and very queer styles also appeared. In the 1780s, they ornamented these hairdos by using various things. This can be considered as women's behaviors that showed off their status and wealth instead of their husbands. Although men's hairstyles were not as huge and decorative as women's, wigs were worn frequently. Wigs became smaller and simpler than those in 17C, and while wearing them, they made wigs whitened by spraying hair-powders enough not to recognize their ages. Several names such as Pig tail, Ramilleis, Bag wig, Brigadiere, and so on existed, according to the way to tie the wigs. Somewhat exaggerated men's hairstyles were shown by Macaronis in 1780s. However, this can be regarded to reflect the situation of the age.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.11
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• pp.1028-1035
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• 2007

this study, forced vibration analysis was performed on the composite main wing structure of a small scale WIG craft which is equipped two-stroke pusher type reciprocating engine. The structural vibration analysis based on the finite element method was performed using a commercial FEM code, MSC/NASTRAN. Excitations for the frequency response analysis were assumed as the H-mode(horizontal mode), the V-mode(vertical mode) and the X-mode(twisted mode) which are typical main vibration modes of engine. And excitations for the transient response analysis were assumed as the L-mode(longitudinal mode) with the oscillating propeller thrust which occurs.

• 한국전산유체공학회:학술대회논문집
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• 1997.10a
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• pp.61-65
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• 1997

A two-dimensional airfoil under ground effect in subsonic turbulent flow is calculated by sieving the Navier-Stokes equation. Some numerical results for different NACA four-digit airfoils are presented. The numerical results show that the lift and drag coefficients are strongly influenced by the shape of the region between the lower surface of airfoil and the ground In general, the airfoil with large camber and small thickness is suitable for WIG vehicles

• The Journal of Natural Sciences
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• v.9 no.1
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• pp.153-168
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• 1997

The purpose of this study was to investigate the formative aesthetic of head accessory design in korean women. Coming to Chosen, women from the court ir the nobility were Jukui, Wonsam, Whalot, Dangui and so on and as for the hair-form in this era, there were a long trees of hair for single and Unzonmeri(By making a tree with hair and raised up roundly) and Jjokmeri(Doing one's hair up in a chignon on the back of one's head) for married, as for a wig for ceremony they used Daeshu(As a same with today's wig added various head accessory design), Kunmeri(Putting a big hair made with a tree of Dukuji on Ayemeri) and Ayemeri(A big hair made with Darae on the head) and as for an head accessory design, there were Biye, Ddelgam and Chupji, which hadn't regularly developed untill the era Chosun. As is known, coming to the era of Chosun, the widely and generally used Biye and Duykokii fitted well to the most usual Jjokmeri.

• Composites Research
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• v.23 no.1
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• pp.44-50
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• 2010

In this paper, two different experiments, namely, salt water spray and salt water immersion, were performed to reproduce the contact of composites with the seawater for three kinds of woven fabric composite material systems which would be used for the WIG(wing in ground effect)craft. After aging 140 days in the salt water environment, material properties of carbon/epoxy and glass/epoxy composite such as tensile, compressive and shear stiffness and strength, and inter-laminar shear strength (ILSS) were measured. By comparing baseline material properties with degraded ones, the effects of the salt water environment on the composite mechanical properties were evaluated. From the experiments, it was confirmed that the difference in aging conditions had very small influence on composite properties. And it was found that tensile strength of carbon/epoxy composites showed little degradation, but much more degradation was observed in glass/epoxy composites. And large degradations on matrix dominant properties were observed. The salt water could damage the fiber-matrix interface, matrix properties and the glass fiber.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.5
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• pp.691-703
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• 2013

The costume culture of ladies in late Goryeo is an important and rare source for cultural fashion souvenir design. This study investigates the historical costume design sources of late Goryeo to suggest high quality traditional and practical ornament souvenir designs for female dolls as well as examples of coordination with doll costumes. The costume culture of late Goryeo contained golden Buddhism and a revival of $12^{th}$ century Goryeo costume characteristic after the period of Mongolian influences from the Yuan. The main sources for doll ornament designs are $14^{th}$ century Buddhist paintings, a few ornament relics of Goryeo, ancient literature, and portraits of ladies in the $14^{th}$ century that originated from five doll's traditional ornaments (lotus hairpin, cloud-shaped hairpin, Buddhist flower hair ornament, vase-shaped Binyeo, and bell of animalhuman face) and three wig designs (wigs from Buddhist paintings and portraits, and hairpiece) with bleached gilding silver, silk, various gemstones and synthetic hair. These doll ornament and wig designs imply the symbol of Buddhism, exorcism, and costume culture of $14^{th}$ century Goryeo ladies that can be matched with two doll gowns, half-sleeved jacket, skirt, two Jogoris, apron, under trousers as formal, semi-formal, and town-wear according to the T.P.O of late Goryeo; in addition, five ornaments can be used as owner's ornaments. The partial changing colors and materials due to the characteristics of doll ornament goods as well as better communication between researcher and constructor remain to be improved.