• 보존과학연구
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• s.31
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• pp.17-30
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• 2010

There were excavated many relics about 200 pieces including gilt-bronze cap, gilt-bronze shoes, bronze mirror and armor, etc. in Ahndong tumulus, Gildu-ri, Goheung. The National Research Institute of Cultural Heritage was undertaking excavation of major damaged relics that were corroded by several environment and were destroyed by a lump of earth. Shoes are consolidated with soils in order to stop destroy during excavation. And these are relocated in order to treat for conservation. Before treatment, X-ray radiography and CT(Computed Tomography) are used in order to examine the original surface and the shape of shoes. As a result, we confirm the condition of shoes. If soils are removed, gilt-bronze shoes are crumbling into little pieces because gilt-bronze shoes are damaged by corrosion and deformation. So, shoes are consolidating with inner soils and are removing outer soils. Throughout conservation treatment, shoes recovered original form and inner soils are consolidated in order to keep the shape of shoes.

• Composites Research
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• v.18 no.6
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• pp.34-39
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• 2005

In this study, we analyzed the relation between physical/mechanical properties and ballistic properties for several engineering ceramics that were expected to use as armor material. After physical/mechanical measurement, we measured ballistic properties about KE(Kinetic Energy, L/D=10.7, tungsten heavy alloy) and HEAT(High Explosive Anti-Tank, K215) projectiles. Increasing Young's modulus/density, hardness/density and flexural strength/density ratios, ballistic properties were generally increased. Especially it appeared that the ballistic property about KE projectile was lineally increased, as HEL/density ratio increased.

• Journal of the Korea Fashion and Costume Design Association
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• v.6 no.1
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• pp.64-72
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• 2004

The purpose of this paper is to investigate the changing fashion image of the glossy materials including metal, leather, vinyl, latex, plastic etc. from 1960's to the present. Glossy materials used in the second half of the 20th century showed a restricted image combined with a specific social circumstance. They expressed a reflection of young and future-oriented space period of 1960s. Many designers like Paco Rabanne and Andre Courreges were concerned with the fashion of space age and expressed that image with leather and synthetic materials including silver leather, metal chain armor, and plastic appeared as the keynote of fashion. In 1970's, glossy material was the symbol of avant-garde and rebellious attitude by the punk fashion. They maximized glamourous look of 1980s, and cyber look with an expectation for a new millenium of 1990s. On the other side, glossy materials seem to be used as a source of various inspiration of fashion designer in the 21st century. Also, some of the past images, for example space look and glamourous look, are revived in the 21 st century by the form of modified design.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.232-237
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• 2007

The deformation of polymers under high loading-rate conditions will be a governing factor to be considered in their impact-resistant applications such as protective shields and transparent armor. In this paper, the deformation and fracture behaviors of polymeric materials such as PE, PC and PEEK have been investigated by Taylor Impact tests. Taylor cylinder impact tests and high speed photography are introduced to examine the deformation behavior under dynamic loading condition. 20 mm air gun was used to perform the impact experiments. Cylindrical projectiles have been impacted onto a hardened steel anvil at a velocity ranging from 100 to $350\;ms^{-1}.$ Along the barrel line, a photo-sensor which measures the speed of the projectile, four digital cameras which has shutter speed of 1/917,000sec and a rigid anvil were set up. After impact experiments, the shapes of projectiles and images taken using high speed cameras were analysed. Depending on materials adopted, they showed a variety in deformation and fracture behaviors.

• Magazine of the Korean Society of Agricultural Engineers
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• v.32 no.1
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• pp.7-16
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• 1990

불규칙파(不規則波)의 피습(被襲)에 의한 사석제(捨石堤)의 호안공(護岸工)이나 방파제(防波堤)에 대하여 화란(和蘭)이 Delft수이시험소(水理試驗所)에서 종합적(綜合的)인 모형연구(模型硏究)를 실시(實施)한 결과(結果) 새로운 안정도(安定度) 공식(公式)을 수립(樹立)하였다. 이들 공식(公式)은 파랑주기(波浪週期), 폭풍지속기간(暴風持續期間) 및 구조물(構造物) 투수성(透水性) 등의 파라미터(媒介變數)가 포함(包含)되어 있으므로 파손(破損)의 정도(程度)가 분명(分明)하여 Hudson형(型) 공식(公式)의 주(主)된 단점(短點)을 해결(解決)하였다. 이들 신공식(新公式)의 개발(開發)은 이전(以前)에도 기술(記述)된바 있으며 본론설(本論說)에는 재론(再論)하지 않는다. 안정도공식(安定度公式)은 파라미터로서 적용(適用)이 가능(可能)한 범위(範圍)가 부여(附與)되었으며, 이들 공식(公式)은 결정론(決定論) 및 확률론적(確率論的) 양자(兩者) 다같이 사용(使用) 방법(方法)이 제시(提示)되어 있다. 결정론적(決定論的) 설계절차(設計節次)는 여러가지지 파라미터의 영향(影響)을 곡선(曲線)으로 나타내어 졌으며 확률론적(確率論的) 설계(設計)는 구조물(構造物)의 내구연수기간내(耐久年數期間內)에 파손도(破損度)의 초과확률(超過確率)을 나타낸 곡선(曲線)으로 되어있다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.784-789
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• 2001

In order to investigate the fracture behaviors(penetration modes) and the resistance to penetration during ballistic impact of cold-rolled Al 5052 H34 alloy laminates, anodized Al 5052 H34 alloy laminates, and Al 5052 H34 alloy after cold-rolling, ballistic testing was conducted. In general, superior armor material is brittle materials which have a high hardness. Ballistic resistance of these materials was measured by protection ballistic limit(V50), a statical velocity with 50% probability for incomplete penetration. Fracture behaviors and ballistic tolerance, described by penetration modes, are observed respectfully, resulting from V50 test and Projectile Through Plate(PTP) test at velocities greater than V50. PTP tests were conducted with 0$^{\circ}$obliquity at room temperature using 5.56mm ball projectile. V50 tests with 0$^{\circ}$obliquity at room temperature were also conducted with projectiles that were able to achieve near or complete penetration during PTP tests. Surface Hardness, resistance to penetration, and penetration modes of Al 5052 H34 alloy laminates compared to those of cold-rolled Al 5052 H34 alloy laminates and anodized Al 5052 H34 alloy laminates anodized Al 5052 H34 alloy after cold-rolling.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.527-532
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• 2000

The armor composite material targets such as aramid FRMLs with different type and ply number of face material and different type of back-up material, were studied to determine ballistic impact resistance and dynamic failure behavior during ballistic impact. Ballistic impact resistance is determined by $\textrm{V}_{50}$ ballistic limit, a statical velocity with 50% probability for complete penetration, test method. Also dynamic failure behaviors are respectfully observed that result from $\textrm{V}_{50}$ tests. $\textrm{V}_{50}$ tests with $0^{\circ}$ obliquity at room temperature were conducted with projectiles that were able to achieve near or complete penetration during high velocity impact tests. As a result, ballistic impact resistance of anodized Al 5052-H34 alloy(2 ply) is better than that of anodized Al 5052-H34 alloy(1 ply), but Titanium alloy showed the similar ballistic impact resistance. In the face material, ballistic impact resistance of titanium alloy is better than that of anodized Al 5052-H34 alloy. In the back-up material, ballistic impact resistance of T750 type aramid fiber is better than that of CT709 type aramid fiber.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.6
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• pp.519-525
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• 2009

The population were increased by industrialization and urbanization of the modern society and social activities of the person were rapid increased too. Subsequently the number of motor vehicle accident, sports accident and industrial accident were increased, resulting in the number of oral and maxillofacial trauma were increased. Because of the mandible relatively protruded among the facial bone, the most frequent associated oral and maxillofacial injuries was mandible fracture in the trauma center setting. A clinical study on 411 patients with mandibular fracture who visited in Department of Oral and Maxillofacial Surgery, Chun-chon Sacred Heart Hospital during 10 years(1997-2006) was done by analysing sex, age, mode, fracture site and treatment method

• Journal of the Korean Home Economics Association
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• v.18 no.4
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• pp.41-45
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• 1980

We must identify the forms of dress devised throughout ages, when we wtudy, interpret and analyze the numerous resource material of costume. The study which depends on reference to actual artifacts is necessarily limited. Whereas items of contemporary dress are readily available, much from earlier eras has been destroyed or has deteriorated through time. Such as cottons, linens, silks, wools, leathers and furs are perishable organic materials. Few garments dated earlier than seventeenth century has survived except armor, jewelry. We have many sources of the information are available to study on costume of earlier eras. These sources are wall paintings, sculptures, painting, monumental brasses, manuscript illustration ceramics, coins, medals, mosaics, archives, literature. Wall painting and frescoes provided an useful source for costume study. Many wall paintings and frescoes were destroyed, were changed in color. It si advisable to interpret the dress detail, form color carefully. Sculpture would be useful to see the back and side views of dress. One of the most important points which should be made abut the use of sculpture as a source for costume study in early periods is that the sculptor's style will often change the character of a costume. As the painting si two-dimensional evidence for a three-dimensional costume, paintings must be accurately studied. What we must do, as far as we can, is to look at all visual representations in the light of other contemporary evidence in order to interpret the information correctly.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.7
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• pp.1426-1437
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• 2002

Using the Lagrangian explicit time-integration finite element code NET3D which can treat three-dimensional high-velocity impact problems, oblique penetration processes of long rod projectile with yaw against thin plate are simulated. Through the comparison of simulation result with experimental result and other code's computational result, the adaptability and accuracy of NET3D is evaluated under the complex situation in which yaw angle and oblique angle exist simultaneously. Main research contents to be handled in this paper include the followings. First, the accuracy and efficiency estimation of NET3D code result obtained from the oblique penetration simulations of long rod projectile with yaw against thin plate. Second, the effect of increasing impact velocity. Third, the effect of initial yaw for the spaced-plate target. Residual velocities, residual lengths, angular velocities, and final deformed configurations obtained from the NET3D computations are compared with the experimental results and other code's computational results such as Eulerian code MESA and Lagrangian code EPIC. As a result of comparisons, it has been found that NET3D code is superior to EPIC code and MESA code in the prediction capability of residual velocity and residual length of penetrator. The key features obtained from the experiment can be successfully reproduced through NET3D simulations. Throughout the study, the applicability and accuracy of NET3D as a metallic armor system design tool is verified.