• Title/Summary/Keyword: bronze

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Performance of a Heat pipe with Axial Grooves Formed from Corrugated Plate (접힌 板材 로 만든 그루우브 를 갖는 熱파이프 에 관한 硏究)

  • 김태현;김기현
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.9 no.1
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    • pp.47-55
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    • 1985
  • Heat pipe with axial grooves formed from corrugated plate in the adiabatic section is studied. The axial grooves made of thin corrugated plate decrease considerably the flow resistance in the adiabatic section without increasing the thermal resistance of the heat pipe, resulting in the increase of the capillary limit, especially in the cases of heat pipes that have long adiabatic section. In the theoretical analysis, it is assumed that the liquid flow in each section laminar and fully developed and Darcy's equation can be applied to each section neglecting the end-effects associated with each transitionary region. A heat pipe which consists of axially corrugated rectangular grooves in the adiabatic section and bronze mesh in the evaporator and codenser sections was made and tested. Comparison of the experimental results, using acetone as the working fluid, with the theoretical result shows satisfactory agreement.

All about Milk: Based on an Information in 1927 (우유에 관한 모든 것: 1927년 발간된 자료를 바탕으로)

  • Oh, Sejong
    • Journal of Dairy Science and Biotechnology
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    • v.38 no.1
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    • pp.45-52
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    • 2020
  • The advent of the Internet and social media has given rise to a number of anti-milk articles that contain a lot of misinformation. Should milk and dairy products really not be consumed past a certain age? To answer this question, the history of milk consumption must be examined to understand the long-term benefits of milk. Historically, dairy products were among the foods served to the angels in the Old Testament of the Bible. Furthermore, dairy products were consumed even before the Bronze Age, and are defined by many food and animal scientists, and nutritionists as a complete food containing a lot of nutrients. Milk and dairy products have significantly contributed to the Korean and Japanese people's current body structures; this is evident in the fact that they are taller than their ancestors, primarily due to the increased consumption of milk and dairy products following industrialization. The average height of Koreans rose drastically in the 1960s, after milk consumption increased as a result of the dairy promotion policy. This article seeks to help understand milk by looking into the content published by a life insurance company in 1927.

Apoptosis in experimentally infected chicks with Salmonella gallinarum

  • Song, Sun-Kyong;Cho, Sung-Whan;Lee, Jong-Hoon;Park, Yeon-Cheol;Shin, Yong-Uk;Park, Il-Gue
    • Korean Journal of Veterinary Service
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    • v.25 no.4
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    • pp.357-370
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    • 2002
  • This experiment was performed to investigate apoptosis during undergoing patho-genesis of Salmonella gallinarum(SG)-infected chicks. 16 days old, 49 chicks was infected with SG (10$\^$6/-10$\^$8/ CFU/㎖) experimentally, they were autopsied to remove liver, spleen, intestine and lung at 1, 6, 12hr, 1, 2, 4 and 7 day post infection(PI) respectively, for H-E and TUNEL staining. Grossly, white foci in the liver and enlarged spleen were seen on 4 day PI and coppery bronze liver, dark-red discolored intestine, green-yellowish discolored and enlarged spleen was observed on 7 day PI. Histopathologically, multi focal necrosis in the liver, follicle hyperplasia in the spleen and inflammatory cells infiltration in the intestine were shown from 2 day PI and more severely observed on 4 day and 7 day PI. In TUNEL analysis, apoptotic cells reached a maximum at 6hr PI in the liver and intestine and at 12hr PI in the spleen, and then decreased the levels of controls by 7 day PI.

Surface Treatment Technology for Metal Corrosion Layer Focusing on Copper Alloy

  • Yang, Eun-Hee;Han, Won-Sik;Choi, Kwang-Sun;Lee, Young-Hoon;Ham, Chul-Hee;Hong, Tae-Kee
    • Journal of the Korean Applied Science and Technology
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    • v.31 no.2
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    • pp.176-182
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    • 2014
  • Using alkali treatment solution, neutrality treatment solution and acid treatment solution, the surface corrosion layer of copper plates and bronze plates that have been artificially corroded using HCl, $H_2SO_4$ and $HNO_3$ solutions were removed. In the case of alkali treatment solution, only air oxidation in the form of black tenorite and white cuproous chloride remained without being removed. In the case of using a neutrality treatment solution, a anhydrous type layer of reddish brown cupric chloride remained without being removed, together with this black and white corrosion substance. In the case of using an acid treatment solution, this red corrosion substance also remained, but all of the oxide was removed on the surface of the specimen that was treated by alternatively using alkali treatment solution and acid treatment solution. In the case of this treatment solution with the order of alkali-acid, oxidation no longer proceeded only through the distilled water cleaning process after treatment, thereby showing that oxidation from the cleaning solution no longer proceeded.

A Study on Shoe Design Affected by Glam Rock (글램 록 스타일 구두 디자인에 관한 연구)

  • Song, Ji-Hyun;Choi, Jeong-Wook
    • The Research Journal of the Costume Culture
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    • v.16 no.6
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    • pp.1156-1168
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    • 2008
  • This study investigated the preceding studies and concept of Glam Rock style, modernistically reinterpreted its aesthetic function and symbolism and connected them to design. It analyzed according to the standards for classification the Glam Rock style appearing mainly in the collections from 2002 S/S to 2007 S/S and presented four pieces of design through the analysis. Its findings are synthesized as follows. First, unstructured design constitutes mule stressing gold cubic overall. It takes an unstable form by the placement of unshapely front ball of foot from transforming Chopin and a relatively poor heel. Second, over trimming constitutes separated pumps in the form of over trimming irregularly a piece of broken glass, metal and thumb tack. Third, Mix & Match combines Boot body of flexible knit material with an acrylic wedge sandal. Fourth, a platform sandal has the structure of color contrast between yellow and bronze in calf fur of tiger-skin pattern. I hope that this study will be developed by reflecting Glam Rock spirit and style as cultural phenomena through analyzing Glam Rock style and presenting design according to selected standards for classification, inferring plastic beauty of fashion shoes from them, investigating the change and feature of age-specific shoe design and making a new attempt possible.

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A Study on Outdoor Diversity of Housing Community in Korea -Especially in Material of Public Art- (공동주택 외부공간의 다양화에 관한 연구 - 미술 장식품의 재료를 중심으로 -)

  • Kim Soon-Boon;Ahn Tong-Mahn
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.3 s.110
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    • pp.43-55
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    • 2005
  • Since 1990s, increasing number of public arts have been installed in housing projects in Korea. Most of them were made of granite, bronze and stainless steel and were sculptures as well. Then it resulted in monotony. New technology and community need various Dials in material and genre of Public art. The author wonders if people really want granite sculpture, so started the study of public arts in housing projects. Unfortunately most of people related public art wanted granite sculpture. But there were some hope in survey. They wanted the other genre and material like ceramic wall, art fountain and landmark tower. This means that they care about real world like vandalism and Product Liability, but also want more fantastic and beautiful world in the second step. Recently, the facades of apartments are changing rapidly as more diverse materials in their forms, textures, and colors. And landscape designs are changing their clothes in every second as well. According to these flows public arts in apartments needs more diversified trial within genres and materials to avoid monotonous outdoor.

Crystallization and Electrical Properties of SBN60 Thin Films Prepared by Ion Beam Sputter Deposition

  • Jang, Jae-Hoon;Jeong, Seong-Won;Lee, Hee-Young
    • Transactions on Electrical and Electronic Materials
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    • v.6 no.1
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    • pp.10-13
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    • 2005
  • $Sr_{0.6}Ba_{0.4}Nb_{2}O_{6}$, hereafter SBN60, thin films of 300 nm thickness were deposited using ion beam sputtering technique, in which sintered ceramic target of the same composition was utilized and the $Ar:O_{2}$ gas ratio was controlled during deposition onto $Pt(100)/TiO_{2}/SiO_{2}/Si$ substrate. Crystallization and orientation behavior as well as electrical properties of the films were examined after annealing treatment at $650{\sim}800{\cric}C$. It was found that the film orientation was dependent upon $Ar:O_{2}$ratio, in which strong (00l) orientation was developed when the gas ratio was about 1:4 at $4.3{\times}10^{-4}$ torr. Typical remanent polarization (2Pr), the coercive field (Ec) and the dielectric constant of Pt/SBN60/Pt thin film capacitor were approximately $10{\mu}C/cm^{2}$, 60 kV/cm, and 615, respectively.

Family of the Sun-and-Stars Time-Determining Instruments (Ilseong-jeongsi-ui) Invented During the Joseon Dynasty

  • Lee, Yong Sam;Kim, Sang Hyuk;Mihn, Byeong-Hee
    • Journal of Astronomy and Space Sciences
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    • v.33 no.3
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    • pp.237-246
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    • 2016
  • We analyze the design and specifications of the Sun-and-Stars Time-Determining group of instruments (Ilseong-jeongsi-ui, 日星定時儀) made during the Joseon dynasty. According to the records of the Sejong Sillok (Veritable Records of King Sejong), Sun-and-Stars Time-Determining Instruments measure the solar time of day and the sidereal time of night through three rings and an alidade. One such instrument, the Simplified Time-Determining Instrument (So-jeongsi-ui, 小定時儀), is made without the essential component for alignment with the celestial north pole. Among this group of instruments, only two bronze Hundred-Interval-Ring Sundials (Baekgak-hwan-Ilgu, 百刻環日晷) currently exist. A comparison of the functions of these two relics with two Time-Determining Instruments suggests that the Hundred-Interval-Ring Sundial is a Simplified Sundial (So-ilyeong, 小日影), as recorded in the Sejong Sillok and the Seongjong Sillok (Veritable Records of King Seongjong). Furthermore, the Simplified Sundial is a model derived from the Simplified Time-Determining Instrument. During the King Sejong reign, the Sun-and-Stars Time-Determining Instruments were used in military camps of the kingdom's frontiers, in royal ancestral rituals, and in royal astronomical observatories.

Horary System of the Early Chosen and the King Sejong′s Striking Clepsydra : (1) Water-Clocks (조선초기의 시제와 세종의 자격루:(1) 물시계)

  • 남문현;한득영
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.697-701
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    • 1996
  • King Sejong's Striking water-clock which brought in use on the first of July in 1434 was mainly composed of timekeeping and time announcing parts signalling twelve double-hours, and five night-watches and night-watch-divisions automatically by means of ball-operating jackworks. The clock was arranged with dual timekeeping system, the one for a full day(twelve double-hours) and the other for five night-watches achieving twelve double-hours and one-hundred interval horary systems. The vessels were arrayed in inflow-type water-clock, a large reservoir on the highest story, a constant-level tank for supplying water to the measuring vessel evenly in the middle, and the lowest tank to receive water from the above constant-level tank. An indicator-rod on the float was raised upwards depending on the water-level increase to show timing scales and also to release small bronze balls from the ball-rack mechanisms implanted on the measuring vessel to signal timing intervals.

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On several questions concerning the reaserch of Zhu culture (젓가락 문화 및 연구에 관한 문제)

  • Zhao, Rongguang;Park, Gi-Suk
    • Journal of the Korean Society of Food Culture
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    • v.17 no.3
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    • pp.337-362
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    • 2002
  • The history and culture of using Zhu to help take food in China is a focal question in contemporary Chinese academic circle and leads to various conflicting ideas. This article, based on original historical documents, archaeological findings, cultural relic authentication, field investigation and the author's long-term thinking, comes up with a series of new conclusions. Firstly, Zhu emerged and developed along with cooked food and granular food served in bowls; secondly, there had been a period of using a single Zhu in China's history before two Zhus being used simultaneously; thirdly, the development of Zhu culture went through five historical periods, namely the former form, the interim form, the Jia form, the Zhu form and chopsticks form. In addition, the author gives out his unique viewpoints on some other relevant questions, including the Zhus which can be dated back to the Neolithic Age unearthed at Longqiuzhuang in Jiangsu province, Jiangzhai in Shanxi province etc, and the bronze utensils in the shape of Zhu unearthed in 1934 at Yin Dynasty ruins in Henan province.