• Title/Summary/Keyword: Control Rod

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Studies on the Nature and Pathogenicity of Nuclear Polyhedrosis Virus of the Fall Webworm, Hyphantria cunea (Drury) (흰불나방 핵다각체병바이러스의 성상과 병원성에 관한 연구)

  • Im Dae Joon;Hyun Jae Sun;Paik Woon Hah;Lim Jong Sung
    • Korean journal of applied entomology
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    • v.18 no.1 s.38
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    • pp.1-10
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    • 1979
  • An inclusion forming virus isolated from a fan webworm, Hyphantria cunea, in 1975 was identified as a nuclear polyhedrosis virus. With the virus isolated in Korea, it was considered that the virus would be one of the valuable microorganism in microbial control. In this connection, 1) the shape and size of the virus for identification, 2) susceptibility of the various instar larvae to the virus, 3) the effects of storage condition on the pathogenicity and the cross infection of the virus to the larvae of Bombyx mori were examined. The results are summarized as follows; 1. The polyhedron was tetrahedron or hexahedron of $2\mu$ in size and the rod-shaped virus particles consisting of $2\~14$ rods in a bundle were $330m{\mu}\times35m{\mu}$ in size. 2. The hexagonal nuclear polyhedra were found only in the nucleus of the midgut cells but were variable in size. 3. The $LD_{50}$ values for the various instar larvae of H. cunea were $8.377\times10^4\;PIBs/ml$ for the second, $4.974\times10^5\;PIBs/ml$ for the fifth instar larvae. The $LT_{50}values$ for $10^6\;PIBs/ml$ were 9.6 days for the second, 11.5 days for the third, 12.0 days for the fourth and 17 days for the fifth instar larvae. 4. The susceptibility of H. cunea to the nuclear polyhedrosis virus was greater in the first generation than in the second generation. 5. The effect of the storage conditions on the pathogenicity of the nuclear polyhedra was less in refrigerator $(5^{\circ}C)$ and in freezing $(-80^{\circ}C)$ than in room temperature $(18.5^{\circ}C)$, especially as air-dried polyhedra than as suspension. The pathogenicity of the polyhedra seemed to decrease by sunlight during storage as cadavers, since rather greater decrease in pathogenicity was found in sunny condition than in shady condition. 6. The effective spray concentration was $6.4\times10^7\;PIBs/ml$ in the field and its $LT_50$ values for the third and the fifth instar larvae were 4.8 days and 14.2 days, respectively. 7. No cross infections were found in the nuclear polyhedrosis virus between H. cunea and B. mori. larvae.

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A STUDY ON THE JUJEON OF AUTOMATIC CLEPSYDRA IN EARLY JOSEON DYNASTY (조선 전기 자동물시계의 주전(籌箭) 연구)

  • YUN, YONG-HYUN;KIM, SANG HYUK;MIHN, BYEONG-HEE;OH, KYONG TAEK
    • Publications of The Korean Astronomical Society
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    • v.36 no.3
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    • pp.65-78
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    • 2021
  • Jagyeokru, an automatic striking water clock described in the Sejong Sillok (Veritable Records of King Sejong) is essentially composed of a water quantity control device and a time-signal device, with the former controlling the amount or the flow rate of water and the latter automatically informing the time based on the former. What connects these two parts is a signal generating device or a power transmission device called the 'Jujeon' system, which includes a copper rod on the float and ball-racked scheduled plates. The copper products excavated under Gongpyeong-dong in Seoul include a lot of broken plate pieces and cylinder-like devices. If some plate pieces are put together, a large square plate with circular holes located in a zigzag can be completed, and at the upper right of it is carved 'the first scheduled plate (一箭).' Cylinder-like devices generally 3.8 cm in diameter are able to release a ball, and have a ginkgo leaf-like screen fixed on the inner axis and a bird-shaped hook of which the leg fixes another axis and the beak attaches to the leaf side. The lateral view of this cylinder-like device appears like a trapezoid and mounts an iron ball. The function of releasing a ball agrees with the description of Borugak Pavilion, where Jagyeokru was installed, written by Kim Don (1385 ~ 1440). The other accounts of Borugak Pavilion's and Heumgyeonggak Pavilion's water clocks describe these copper plates and ball releasing devices as the 'Jujeon' system. According to the description of Borugak Pavilion, a square wooden column has copper plates on the left and right sides the same height as the column, and the left copper plate has 12 drilled holes to keep the time of a 12 double-hours. Meanwhile, the right plate has 25 holes which represent seasonal night 5-hours (Kyeong) and their 5-subhours (Jeom), not 12 hours. There are 11 scheduled plates for seasonal night 5-hours made with copper, which are made to be attached or detached as the season. In accordance with Nujutongui (manual for the operation of the yardstick for the clepsydra), the first scheduled plate for the night is used from the winter solstice (冬至) to 2 days after Daehan (大寒), and from 4 days before Soseol (小雪) to a day before the winter solstice. Besides the first scheduled plate, we confirm discovering a third scheduled plate and a sixth scheduled plate among the excavated copper materials based on the spacing between holes. On the other hand, the width of the scheduled plate is different for these artifacts, measured as 144 mm compared to the description of the Borugak Pavilion, which is recorded as 51 mm. From this perspective, they may be the scheduled plates for the Heumgyeonggak Ongru made in 1438 (or 1554) or for the new Fortress Pavilion installed in Changdeokgung palace completed in 1536 (the 31st year of the reign of King Jungjong) in the early Joseon dynasty. This study presents the concept of the scheduled plates described in the literature, including their new operating mechanism. In addition, a detailed model of 11 scheduled plates is designed from the records and on the excavated relics. It is expected that this study will aid in efforts to restore and reconstruct the automatic water clocks of the early Joseon dynasty.

Seasonal color change of the oxyhydrous precipitates in the Taebaek coal mine drainage, south Korea, and implications for mineralogical and geochemical controls

  • Kim, J. J.;C. O. Choo;Kim, S. J.;K. Tazaki
    • Proceedings of the Mineralogical Society of Korea Conference
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    • 2001.06a
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    • pp.38-39
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    • 2001
  • The seasonal changes in pH, Fe, Al and SO$_4$$\^$2-/ contents of acid drainage released from coal mine dumps play a major role in precipitation of metal hydroxides in the Taebaek coal field area, southeastern Korea. Precipitates in the creeks underwent a cycle of the color change showing white, reddish brown and brownish yellow, which depends on geochemical factors of the creek waters. White precipitates consist of Al-sulfate (basaluminite and hydrobasaluminite) and reddish brown ones are composed of ferrihydrite and brownish yellow ones are of schwertmannite. Goethite coprecipitates with ferrihydrite and schwertmannite. Ferrihydrite formed at higher values than pH 5.3 and schwertmannite precipitated below pH 4.3, and goethite formed at the intermediate pH range between the two minerals. With the pH being increased from acid to intermediate regions, Fe is present both as schwertmannite and goethite. From the present observation, the most favorable pH that basauluminte can precipitate is in the range of pH 4.45-5.95. SEM examination of precipitates at stream bottom shows that they basically consist of agglomerates of spheroid and rod-shape bacteria. Bacteria species are remarkably different among bottom precipitates and, to a less extent, there are slightly different chemical compositions even within the same bacteria. The speciation and calculation of the mineral saturation index were made using MINTEQA2. In waters associated with yellowish brown precipitates mainly composed of schwertmannite, So$_4$ species is mostly free So$_4$$\^$2-/ ion with less AlSo$_4$$\^$+/, CaSo$\sub$(aq)/, and MgSo$\sub$4(aq)/. Ferrous iron is present mostly as free Fe$\^$2+/, and FeSo$\sub$4(aq)/ and ferric iron exists predominantly as Fe(OH)$_2$$\^$+/, with less FeSo$\sub$4(aq)/, Fe(OH)$_2$$\^$-/, FeSo$_4$$\^$-/ and Fe$\^$3+/, respectively Al exists as free Al$\^$3+/, AlOH$_2$$\^$-/, (AlSo$_4$)$\^$+/, and Al(So$_4$)$\^$2-/. Fe is generally saturated with respect to hematite, magnetite, and goethite, with nearly saturation with lepidocrocite. Aluminum and sulfate are supersaturated with respect to predominant alunite and less jubanite, and they approach a saturation state with respect to diaspore, gibbsite, boehmite and gypsum. In the case of waters associated with whitish precipitates mainly composed of basaluminite, Al is present as predominant Al$\^$3+/ and Al(SO$_4$)$\^$+/, with less Al(OH)$\^$2+/, Al(OH)$_2$$\^$+/ and Al(SO$_4$)$\^$2-/. According to calculation for the mineral saturation, aluminum and sulfate are greatly supersaturated with respect to basaluminite and alunite. Diaspore is flirty well supersaturated while jubanite, gibbsite, and boehmite are already supersaturated, and gypsum approaches its saturation state. The observation that the only mineral phase we can easily detect in the whitish precipitate is basaluminite suggests that growth rate of alunite is much slower than that of basaluminite. Neutralization of acid mine drainage due to the dilution caused by the dilution effect due to mixing of unpolluted waters prevails over the buffering effect by the dissolution of carbonate or aluminosilicates. The main factors to affect color change are variations in aqueous geochemistry, which are controlled by dilution effect due to rainfall, water mixng from adjacent creeks, and the extent to which water-rock interaction takes place with seasons. pH, Fe, Al and SO$_4$ contents of the creek water are the most important factors leading to color changes in the precipitates. A geochemical cycle showing color variations in the precipitates provides the potential control on acid mine drainage and can be applied as a reclamation tool in a temperate region with four seasons.

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A Comparative Study on Buddhist Painting, MokWooDo (牧牛圖: PA Comparative Study on Buddhist Painting, MokWooDo (牧牛圖: Painting of Bull Keeping) and Confucian/Taoist Painting, SipMaDo (十馬圖: Painting of Ten Horses) - Focused on SimBeop (心法: Mind Control Rule) of the Three Schools: Confucianism, Buddhism and Taoism -nd Control Rule) of the Three Schools: Confucianism, Buddhism and Taoism - (불가(佛家) 목우도(牧牛圖)와 유·도(儒·道) 십마도(十馬圖) 비교 연구 - 유불도(儒佛道) 삼가(三家)의 심법(心法)을 중심으로 -)

  • Park, So-Hyun;Lee, Jung-Han
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.40 no.4
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    • pp.67-80
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    • 2022
  • SipWooDo (十牛圖: Painting of Ten Bulls), a Buddhist painting, is a kind of Zen Sect Buddhism painting, which is shown as a mural in many of main halls of Korean Buddhist temples. MokWooDo has been painted since Song Dynasty of China. It paints a cow, a metaphor of mind and a shepherd boy who controls the cow. It comes also with many other types of works such as poetry called GyeSong, HwaWoonSi and etc. That is, it appeared as a pan-cultural phenomenon beyond ideology and nation not limited to Chinese Buddhist ideology of an era. This study, therefore, selects MokWooDo chants that represent Confucianism, Buddhism and Taoism to compare the writing purposes, mind discipline methods and ultimate goals of such chant literatures in order to integrate and comprehend the ideologies of such three schools in the ideologically cultural aspect, which was not fully dealt with in the existing studies. In particular, the study results are: First, the SipWooDo of Buddhist School is classified generally into Bo Myoung's MokWooDo and Kwak Ahm's SimWooDo (尋牛圖: Painting of Searching out a Bull). Zen Sect Buddhism goes toward nirvana through enlightenment. Both MokWooDo and SimWooDo of Buddhist School are the discipline method of JeomSu (漸修: Discipline by Steps). They were made for SuSimJeungDo (修心證道: Enlightenment of Truth by Mind Discipline), which appears different in HwaJe (畫題: Titles on Painting) and GyeSong (偈頌: Poetry Type of Buddhist Chant) between Zen Sect Buddhism and Doctrine Study Based Buddhism, which are different from each other in viewpoints. Second, Bo Myoung's MokWooDo introduces the discipline processes from MiMok (未牧: Before Tamed) to JinGongMyoYu (眞空妙有: True Vacancy is not Separately Existing) of SsangMin (雙泯: the Level where Only Core Image Appears with Every Other Thing Faded out) that lie on the method called BangHalGiYong (棒喝機用: a Way of Using Rod to Scold). On the other side, however, it puts its ultimate goal onto the way to overcome even such core image of SsangMin. Third, Kwak Ahm's SimWooDo shows the discipline processes of JeomSu from SimWoo (尋牛: Searching out a Bull) to IpJeonSuSu (入鄽垂手: Entering into a Place to Exhibit Tools). That is, it puts its ultimate goal onto HwaGwangDongJin (和光同塵: Harmonized with Others not Showing your own Wisdom) where you are going together with ordinary people by going up to the level of 'SangGuBori (上求菩提: Discipline to Go Up to Gain Truth) and HaHwaJungSaeng (下化衆生: Discipline to Go Down to Be with Ordinary People)' through SaGyoIpSeon (捨敎入禪: Entering into Zen Sect Buddhism after Completing a Certain Volume of Doctrine Study), which are working for leading the ordinary people of all to finding out their Buddhist Nature. Fourth, Shimiz Shunryu (清水春流)'s painting YuGaSipMaDo (儒家十馬圖: Painting of Ten Horses of Confucian School) borrowed Bo Myoung's MokWooDo. That is, it borrowed the terms and pictures of Buddhist School. However, it features 'WonBulIpYu (援佛入儒: Enlightenment of Buddhist Nature by Confucianism)', which is based on the process of becoming a greatly wise person through Confucian study to go back to the original good nature. From here, it puts its goal onto becoming a greatly wise person, GunJa who is completely harmonized with truth, through the study of HamYang (涵養: Mind Discipline by Widening Learning and Intelligence) that controls outside mind to make the mind peaceful. Its ultimate goal is in accord with "SangCheonJiJae, MuSeongMuChee (上天之載, 無聲無臭: Heaven Exists in the Sky Upward; It is Difficult to Get the Truth of Nature, which has neither sound nor smell)' words from Zhōngyōng. Fifth, WonMyeongNhoYin (圓明老人)'s painting SangSeungSuJinSamYo (上乘修真三要: Painting of Three Essential Things to Discipline toward Truth) borrowed Bo Myoung's MokWooDo while it consists of totally 13 sheets of picture to preach the painter's will and preference. That is, it features 'WonBulIpDo (援佛入道: Following Buddha to Enter into Truth)' to preach the painter's doctrine of Taoism by borrowing the pictures and poetry type chants of Buddhist School. Taoism aims to become a miraculously powerful Taoist hermit who never dies by Taoist healthcare methods. Therefore, Taoists take the mind discipline called BanHwanSimSeong (返還心性: Returning Back to Original Mind Nature), which makes Taoists go ultimately toward JaGeumSeon (紫金仙) that is the original origin by changing into a saint body that is newly conceived with the vital force of TaeGeuk abandoning the existing mind and body fully. This is a unique feature of Taoism, which puts its ultimate goal onto the way of BeopShinCheongJeong (法身淸淨: Pure and Clean Nature of Buddha) that is in accord with JiDoHoiHong (至道恢弘: Getting to Wide and Big Truth).