• Tribology and Lubricants
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• v.10 no.1
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• pp.1-9
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• 1994

어떤 유체는 전기장에서 순간적으로 고체화한다. 이러한 다변형의 물질은 더욱 신속하고 적절한 기계의 앞날을 약속하고 있다. T-1000 (영화 터미네이터2; 심판의 날에서 생동하는 거의 불멸의 로보트)는 능숙하게 액체에서 고체로 변환다. T-1000은 총탄으로 관통되었을 때, 로보트의 액체-금속 피부는 관통된 구멍으로 흘러 들어가고, 산산조각이 났을때 T-1000은 녹아버린 후에 다시 제원형으로 응결된다. 전기유변성 유체는 이 영화제작자의 상상력에 어느 정도 적용될 수 있을 것이다. 전기유변성 유체는 전기장이 있는 곳에서 변형을 일으키는 물질이다. 주어진 전기장의 세기에 따라 전기유변성 유체는 물처럼 자유롭게 흐르기도 하고, 꿀처럼 진득하게 흐르기도 하며 제라틴처럼 고체화하기도 한다. 참으로 물질이 수천분의 일초사이에 한상태에서 다른 상태로 변할 수 있는 것이다. 전기유변성 유체는 만들기 쉽다; 절연액체에 미시적 입자가 분산된 것이다. 그러나 아직은 상업용으로 쓰이지 못하고 있다. 여러가지 문제점 중의 하나가 고체로서는 구조적으로 약하고, 또, 액체로서는 마찰성이 문제이며, 특히 고온에서는 화학적으로 불안정하다는 것이다.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.248-253
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• 2006

The present study describes the preliminary evaluation of the cytotoxicity from Gleditsiae Semen extracts. G. Semen was extracted with methanol, ethanol, and acetone, and then cytotoxic effect of these extracts was measured by the MTT reduction assay and phase-contrast microscopy on the HT-29 human colon carcinoma cells. Among these extracts, methanol extract showed the highest cytotoxic activity on the HT-29 cells. The methanol extract was further fractionated with n-hexane, diethyl ether, ethyl acetate, and water layer according to the degree of polarity. The water layer showed the highest inhibitory activity on the growth of HT-29 cells, but the other fractions indicated the low cytotoxic activity. In addition, water layer also showed the cytotoxic activity against SW620 human colon carcinoma cells. Based on these results, we suggest that extracts of G. Semen may contain bioactive materials and are potential candidates as chemotherapeutic agents against human colon carcinoma cells.

• Journal of architectural history
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• v.26 no.4
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• pp.19-34
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• 2017

The purpose of this study was to comprehend the assignment and the procurement method of wood works' craftsman through the Salleung-dogamuigwes in royal tombs constructions in the late Joseon period. Following conclusions have been reached through the study. First, Carpenter and other nine craftsmen were introduced in carpentry works. The craftsmen were put in by occupation to maintain the quality of the government building construction by wood processing area. It was distinguished by frame member, Sujangjae, window framing wood, decorative member. Second, sawyer showed a sharp increase in the latter half of the 18th century and declined since the middle of the 19th century. This is closely related to the increase in demand for building materials and the growth of civilian wood products. As a maximum of 300 people have been assigned to the craftsmen in the woodwork, it can be seen that the work has been divided by the process. Third, the national carpenter was difficult to procure from the 17th century to the beginning of the 18th century. From the middle 18th century, the system procuring national carpenter was stabilized. In the 19th century, the input ratio of the national craftsmen seems to have decreased significantly and seems to have kept it at the minimum level. Forth, sawyer were procured through Seongonggam from the late 18th century through the mid 19th century. That means that the role of the sawyer had become important. Since Jogakjang is not a necessary manpower, it usually has civilian artisans.

• KSBB Journal
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• v.9 no.2
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• pp.165-173
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• 1994

In this paper we have described the structural characterization of recombinant bovine somatotropin produced in Escherichia coli. Recombinant bovine somatotropin consists of 191 amino acid residues with a calculated molecular weight of 21,802 Da. For fragmentation of recombinant bovine somatotropin, we have used trypsin, Staphylococcus aureus V8 pretease, CNBr, and mild acid hydrolysis method. Digestion and cleavage with these proteases and chemicals yielded peptides of various size for amino acid sequence determination. The N-terminal sequence analysis was carried out up to thirty residues. Because the design of the recombinant bovine somatotropin gene for expression was such that the coding sequence begins with an initiation codon, AUG, before Ala, the first amino acid of bovine somatotropin, we could expect the initial amino acid as N-formyl Met. But the first amino acid of this protein, expressed in E. coli cells as inclusion bodies, was Ala. And the amino acid composition of RP-HPLC purified recombinant bovine somatotropin was determined and no essencial difference was observed. The amino acid sequence of the recombinant bovine somatotropin was identical to that predicted from its recombinant gene. There was no processing or replacement of amino acid residues in recombinant bovine somatotropin expressed in E. coli. The hydropathy plot of recombinant bovine somatotropin revealed a hydrophobic region at the NH2-terminus and hydrophilic region at the COOH-terminus. The E. coli expression system is thought to be valuable for the expression of recombinant bovine somatotropin because protein was processed to remove the N-terminal Met residue by methionyl-aminopeptidase autonomously.

• Korean journal of applied entomology
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• v.30 no.3
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• pp.219-226
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• 1991

A cytoplasmic polyhedrosis virus isolated from the oriental tobacco budworm, Heliothis assulta (HaCPV), was studied on morphology of the polyhedron and virus particles, analysis of viral protein and nucleic acid, and bioassay of the HaCPV to determine the feasibility of application as a microbial control agent. The shape of polyhedron was hexagonal ranging 0.5-3.7 ${\mu}m$ and the virus particles were icosahedral outline measured 55 nm in diameter. Polyhedral protein was composed of a major polypetide of 24.3 Kd and 5 minor components and virus particle had seven polypeptides ranging in 28.0 Kd-133. 6 Kd by the SDS-P AGE. The genome of virus was segmented with 10 double stranded RNA in the total mol. wt. of 18.08 Md ranging in 0.65 Md -2.79 Md. The $LC_{50}$ values of the HaCPV to the 3rd instar of H. assulta larvae were calculated to $2.895{\times}10^5PIBs/ml$. The $LT_{50}$ values in the concentration of $5.0{\times}10^{6}PIBs/ml$ was 16.4 days.

• Venture DIGEST
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• no.12 s.125
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• pp.22-25
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• 2008

컴퓨터를 켜면서 하루를 시작하고 전원 스위치를 내리면 하루 일과도 마감이다. 컴퓨터와 통신은 이제 펜이나 종이보다 밀접하다. 그래서인지 가끔 자판이 아니라 볼펜으로 메모할 일이 생겼을 때 당황스런 일이 발생하기도 한다. 맞춤법이 생각나지 않는 것이다. 때로는 맞게 써 놓고도 어색함에 자판을 만져보기도 한다. 손으로 꼼꼼하게 적어놓았던 예전 메모장처럼, 혹은 읽은 책에서 좋아하는 내용을 표시할 때 우리는 작은 종이 조각이나 포스트잇 같은 걸 사용한다. 전원만 내리면 아무것도 아닌 컴컴한 모니터에도 포스트잇이 있다. 전화번호나 할 일을 적어놓은 종이쪽지가 아닌 온라인 포스트잇의 이름은 '즐겨찾기'. '즐겨찾기'라고 이름 붙인 사람이 이 말에 특허를 냈다면 아마 지금쯤 엄청난 수익을 거뒀을 거 같다. 입에 딱딱 붙는 이 '즐겨찾기'라는 것은 사람마다 당당하게 밝힐 숭 있는 목록이 있는가하면 자신만이 알 수 있는 암호로 즐겨찾기 목록을 꾸며놓기도 한다. 자, 그렇다면 중소벤처기업 CEO들은 주로 어떤 사이트를 방문할까? 10의 중소벤처기업 CEO의 즐겨찾기와 추천사이트를 소개한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.1020-1023
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• 2005

The fluid flow and thermal analysis were carried out by using the finite element program, Ansys. In analysis process, a electromagnetic analysis was accomplished. In afterwards, Fluid and thermal analysis was done. Fluid flow and heat could be produced by electromagnetic pump. In other words, A magnetic field which electromagnetic pump generates influences Liquid Material(Al alloy). This paper calculates the fluid flow and temperature distribution according to time. Using material is Al alloy(A356).

• Korean Journal of Heritage: History & Science
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• v.53 no.3
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• pp.24-41
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• 2020

The engraved line expression in metal crafts is a detailed technique of carving or decorating metal surfaces. This technique engraves a line using a tool on the surface of a metal craft. This technique was used extensively in articles made of various metal materials during the Goryeo Dynasty, and the range of patterns that could be expressed and the width of users was wide. In this paper, based on relics and literature, the concept of line representation of this engraving technique used in the metal crafts of the Goryeo Dynasty and the perceptions and terms of the Goryeo Dynasty were examined. In addition, the users engaged in this craft and the specific patterns and patterns of decoration were reviewed. Through these means, it was possible to confirm various aspects of a technique that was thought previously to involve just simple expression of lines using tools. In addition, through the literature, Geumseokmun Gate, and relics currently being transmitted, it was possible to confirm the utilization patterns of techniques used in various types of objects. Various uses have led to the combination with other metal craft techniques that were popular at the time, and while utilizing unique characteristics of the techniques, this maximized the molding of various patterns. In the meantime, it is true that the intaglio technique in metal crafts has not received much attention compared to the decoration techniques of other metal crafts, such as inlay, embossing, and openwork techniques in which decorative effects are maximized due to the recognition that the technique was used so widely in relics. However, the universality of the technique is premised on its wide use across all eras. As such, it was used in metal craft relics that reflect the various cultural characteristics of Korea and various cultural aspects that are currently passed down. On the one hand, technology has been passed down as a form of intangible heritage that embodies a longstanding craft culture which continues to the present in the fields of sculpture and intangible cultural properties. As such, the universality of Seongak contains many cultural meanings. In addition, the uniqueness of the technique is distinct, and it is deeply related to Goryeo, who was in charge of the use of technology and craftsmanship of the Joseon Dynasty and the metal craft technology that is currently handed down. I think research on future techniques should be continued in depth.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.42.2-42.2
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• 2018

고전적인 소행성과 혜성의 경계는 무너지고 있다. 처음 발견했을 때는 소행성으로 분류됐던 천체도, 예기치 않은 활동성이 나타나면 혜성의 일원이 된다. 소행성은 충돌이나 회전가속에 의해 갑자기 활동성을 나타내기도 하지만, 강한 태양복사를 견디지 못하고 오랜 시간 간직해온 휘발성 물질을 우주 공간으로 흩뿌리기도 한다. 한국천문연구원 딥사우스 (DEEP-South) 팀은, 이렇게 태양 근방에서 혜성으로 탈바꿈할 것으로 예상되는 소행성으로 2000 XO8을 지목하고, 근일점을 막 지난 2017년 10월 말부터 KMTNet 망원경으로 약 한 달간 지속 관측을 하였다. 이 기간 동안 2000 XO8은 활동성이 급격히 증가하여 선명한 꼬리를 나타냈고, 이내 검출 한계 이하로 활동성이 줄어드는 것까지 확인하였다. 이번에 혜성으로 밝혀진 2000 XO8은 한국인 또는 한국 기관에서 새로 발견 및 동정한 것으로 알려진 혜성 중에 그 주기가 8.8년으로 가장 짧다. 이는 궤도장반경이 목성보다 안쪽에 위치한다는 점에서 이례적인 일이다. 우리는 궤도 실험을 통해 2000 XO8이 현 궤도에 자리 잡은 지 오래 되지 않았으며, 또 다른 주기 혜성 265P/LINEAR에서 쪼개져 나온 조각일 가능성을 제시하고자 한다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.1
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• pp.79-88
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• 2014

We have developed a smart decontamination device for small-size radioactive scrap metal (SSRSM) necessarily generated from nuclear facilities. This is a multi-modal device such as rotation of magnetic field focusing on the region containing the abrasion pins placed around target and ultrasonic cleaner. Additionally, in order to increase the decontamination efficiency we have modified some configuration of the device so that it could work on them evenly and totally. With the Optimal operating for operation of the new device, we tried to decontaminate some various metal selected as a sample during 15 minutes sequentially using each method, magnetic and ultrasonic device. As a result, the range of decontamination factor has been highly increased to 18~56. After decontamination, all samples were found its activity less than background level.