• 헤리티지:역사와 과학
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• 제49권4호
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• pp.126-155
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• 2016

이 글에서는 분묘 출토품을 중심으로 마한 토기에 대하여 몇 가지 문제를 살펴보았다. 유개대부호, 원저소옹, 와질토기, 원통형토기 등은 낙랑을 포함하는 북방지역의 문물을 입수하기 위해 범한반도남부, 즉 '한(韓)'의 차원에서 활발하게 이루어진 교류 과정에서 등장한 것이다. 특히, 중서부지역, 충청내륙 및 영남지역을 연결하는 루트에서 중요한 역할을 수행하였다. 이 단계까지 철기문화는 한반도 남부지역이 유사하다. 내륙 루트 이외에도 서해안을 따라 연안항로도 이용된 흔적이 원통형토기, 유개대부호와 함께 사용된 뚜껑의 변화형 등에서 보인다. 이러한 문물교류의 결절점에 위치한 아산만 일대에서 마한의 중심적인 세력이 등장한 것은 어쩌면 당연한 현상일 것이다. 이후 이중구연호 등 마한 독자 형식의 토기 양식이 성립하는 것은 3세기부터이다. 3세기 이후 마한의 토기는 묘제의 선택에 따라 지역별로 달라지는데, 분구묘와 주구토광묘 축조 전통의 구분과 대개 일치한다. 그러나 분구묘 축조 집단에서도 지역에 따라 이중구연호 등 특정 기종을 선호하는 등의 차이가 보이며 좁은 범위 안에서 특수한 양식을 사용하기도 한다. 이러한 토기류는 상호 교류의 과정에서 주변지역으로 확산되며 매장의례에도 사용된다.

• Journal of Welding and Joining
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• 제30권6호
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• pp.120-125
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• 2012

Because ships and offshore structures have very large dimensions and complicated shapes, it is difficult to determine the deformation or internal stress in the structure by simple lab tests. Thus, a rigorous analysis by using the computer simulation technology is essential for obtaining their distortions by considering the entire production process characteristics. The rapid development of computer technology made it possible to analyze the heat transfer phenomena, deformation and phase transformation in the welded joint. For large shell structures, shell elements modeling contributed primarily to this development. But if a welding is done by multi-pass, shell elements whose thickness are unchangeable can hard to describe the local situation. Recently, it was researched how to introduce the imaginary temperature for V grooved multi-layer butt welding in strain-boundary method (a kind of shrinkage methodologies). In the present study, we formulated the imaginary temperature for the double bevel and double V groove by considering the thickness change of each pass through the bead and the thickness directions simultaneously and also demonstrated the feasibility of the formula by applying it to the thermal distortion analysis of the erection process of crane pedestal.

• 대기
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• 제21권4호
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• pp.455-469
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• 2011

The Chugudae is a pedestal for the Chugugi. While many Chugudae were made during the Joseon Dynasty period, seven remained in existence until the early 20th century. Only five of them remain to this day-Gwansanggam (Royal Office of Astronomy and Meteorology), the Seonhwadang in Daegu, the Changdeok Palace, Tongyeong, and Yeongyeongdang. The Changdeok Palace Chugudae is the only existing model made not only as a meteorological instrument but also as a memorial statue. It has been a challenge to decipher 41 of the 368 characters in 'Chugugi-myeong (The title of the inscriptions on the Changdeok Palace Chugudae)' as these had been eroded. However, the interpretation of the full text of 'Chugugi-myeong' became possible thanks to the "Cheoljae Jinjeok (澈齋眞蹟)" which was discovered through this study. The key sentences of the 'Chugugi-myeong' include the reason for creation, the size and functions of the Chugugi and a eulogy to the reigns of King Sejong, Youngjo and Jeongjo. Moreover, its splendid design is worthy of further study. To conclude its true meaning and value, the Changdeok Palace Chugudae requires a more extensive investigation from the viewpoint of an art history.

• 한국공작기계학회논문집
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• 제16권1호
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• pp.92-97
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• 2007

This study was carried out to minimize the lifting force and to design the slim sized frame of a height adjustment mechanism. This unit is designed for the display devices in order to enhance the ergonomics for effective height adjustment as well as to achieve much slimmer frame for the pedestal. A tolerance analysis of 6 sigma was applied to achieve smooth lift at design stage not to change the tolerance specification of gap several times in a roller type of lifting mechanism at mass production stage. The specification of minimum gap and the target of production yield ratio were agreed with a quality team before tooling. A DFSS simulation on drawings had been done with reasonable tolerance and achievable standard deviation(${\sigma}$) several times until the target specification of gap and yield ratio was met. Once tolerance and deviation(${\sigma}$) were fixed tooling start was done successfully. A CAE method was applied to achieve a slim design. Design parameters were frozen when those parameters matched the reference strength data of standard model. Through those tolerance analysis and CAE simulation the number of tool modification was reduced and production yield ratio was raised up without arguing quality specification at production stage in the end.

• 보존과학연구
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• 통권30호
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• pp.171-187
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• 2009

The Seated iron Vairocana Buddha statue of Dopiansa Temple, Cheolwon was designated National treasure No. 63, it is very important to rearch about Korean Buddha statue because it has an inscription on the back indicates that it was made in 865 A.D., the fifth year of the reign of King Gyeongmun(861-875) of Unified Silla(668-935), through the devoted faith of some 1,500 Buddhist followers of the Cheorwon-gun area. In this conservation treatment, for the Seated iron Vairocana Buddha statue of Dopiansa Temple, Cheolwon plating layer and cashew paint layer of the iron pedestal were removed and for the paint the Body of the Buddha, fake metal layer and plaster layer were removed, stabilizing treatment and coating treatment were done, and removal and restoration of earlobe which had been damaged and later was restored with plaster in the regilding in 1988, and the white hair on forehead was replaced with material of rock crystal, and conch-shaped hair damaged was restored on 35 spots.

• 한국도로학회논문집
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• 제2권4호
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• pp.123-131
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• 2000

아스팔트 포장의 배합설계 방법에서 사용하고 있는 마샬시험 장치는 다짐장치와 안정도 헤드의 주요한 두 부분으로 이루어져 있다. 다짐장치는 시료의 공극과 다짐도에 영향을 미치며 안정도헤드는 마샬안정도와 흐름치에 영향을 주기 때문에 다짐장치의 규격과 타격에너지, 안정도헤드의 형상은 어떠한 경우라도 일치하여야 배합설계시 최적아스팔트 함량을 정확하게 분석 할 수 있다. 그러나, 본 연구의 결과에 의하면 국내에서 사용되고 있는 마샬시험 장치는 서로 다른 규격과 형상을 가지고 있음은 물론, 각 기관마다 다짐장치를 설치하는 조건과 각 제조회사 장치의 받침목이 서로 상이하여 시험 결과의 오차는 물론 아스팔트 포장의 공용성에도 크게 영향을 미치기 때문에 마샬시험 장치의 범 국가적인 재정비가 필요한 것으로 나타났다.

• 한국도로학회논문집
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• 제10권3호
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• pp.1-10
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• 2008

기존의 공진주 비틂 전단 시험기는 길이와 지름의 비율이 2:1의 시료를 사용하고 이는 가진 시스템의 최대 회전시 대략 1.5%의 최대 전단 변형율을 일으킨다. 이번 연구의 목적은 대변형을 일으킬수 있는 공진주 비틂 전단 시험기의 수정이다. 수정 작업으로는 가진시스템의 왕복거리 한계의 극복을 위한 새로운 기초 받침 개발과 비틂력을 증가시키기 위한 코일 감는 방법의 변형이다. 가진 시스템의 새로운 코일감는 방법이 전자석 시스템에서 비틂력에 미치는 영향이 평가 되었고 모래를 시험한 수정된 장치의 응용이 기술되었다.

• 보존과학연구
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• 통권13호
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• pp.14-36
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• 1992

The investigation has been made on the rocks consisting the pagoda(12), Buddhist Statues(9) Buldaejwa and cakra(2, rewpectively), stele(5), and Flagpole wupport and stupa(6) which are stood in Weonju city, Weonju-gun, Hwoengseong-gun and Hongcheon-gun, Kangweondo. These rock-monuments range mostly in age from late Shilla Kingdom to middle Korye Kingdom. The geology around this region is mainly composed of Precambrian metamorphic rocks and mesozoic granitic rocks. The granitic rocks are largely divided into Jurassic and cretaceous ones which are slightly different in rock phase. The main rock phase consisting the monumentsare are coarse biotite granite with minor amount of hornblende in Jurassic age. Variation in rock phase is abserved even in part of the stone used in the monuments. Inclusions composed of biotite and hornblende, porphyritic texture with microcline phenocryst, igneous lineation and exfoliation according to weathering are observable in all rocks in these monuments. In the case of stele whose a body and a capstone is remained, one is composed of black slate and the other white limestone. But the turtle shaped pedestal is constituted of coarse biotite granite. These stone-monuments are strongly weathered and exfoliated out about 1∼2mm.In case of exfoliated weathering along igneous lineation, some are taken off about 3∼5mm thick. In some monuments, the degree of weathering is somewhat different according to position, grade of sculpture, and biological activity.

• Bulletin of the Korean Chemical Society
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• 제31권1호
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• pp.162-167
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• 2010

We investigated the adsorption and desorption characteristics of benzene molecules on $Si(001)-2{\times}n$ surfaces using a variable-low temperature scanning tunneling microscopy. When benzene was adsorbed on a $Si(001)-2{\times}n$ surface at a low coverage, five distinct adsorption configurations were found: tight-binding (TB), standard-butterfly (SB), twisted-bridge, diagonal-bridge, and pedestal. The TB and SB configurations were the most dominant ones and could be reversibly interconverted, diffused, and desorbed by applying an electric field between the tip and the surface. The population ratios of the TB and SB configurations were affected by the benzene coverage: at high coverage, the population ratio of SB increased over that of TB, which was favored at low coverage. The desorption yield decreased with increasing benzene coverage and/or density of vacancy defect. These results suggest that the interaction between the benzene molecules is important at a high coverage, and that the vacancy defects modify the adsorption and desorption energies of the benzene molecules on Si(001) surface.

• Journal of electromagnetic engineering and science
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• 제1권1호
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• pp.67-72
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• 2001

In this paper, the plano-convex lens antenna fed by a single patch is studied for a microwave remote-traffic monitoring sensor with constraints of small size and low cost. Measurement of an AUT (Antenna Under Test) involves the considerations of a triangular groove for matched layer and metallic shielding effects. A formulation for extracting the parameters of a piano-convex lens antenna, based on geometrical optics, is introduced using Fermat`s principle of the equi-phased ray condition. Teflon ($\varepsilon_{{\gamma}}$/ =2.0) is chosen as a material of a plano-convex lens antenna for adjustment of aberrations on the lens surfaces automatically. A fabricated plano-convex lens shows 3-dB beamwidth of 7.5 degree and side-lobe level of -29 dB with an aperture distribution of the parabolic-squared taper on pedestal. This lens supports easier integration with the planar microwave circuits by using a microstrip single patch as a primary feeder of the lens antenna.feeder of the lens antenna.