• Title/Summary/Keyword: 전자관

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Some Mineralogical and Physico-Chemical Properties of Fuller's Earths from Tertiary Sediments in South Korea (삼기층중(三紀層中)에서 산출(産出)되는 산성백토(酸性白土)에 관(關)한 광물학적(鑛物學的) 조성(組成) 및 물리화학적(物理化學的) 성질(性質)에 관(關)하여)

  • Moon, Hee Soo;Morgan, D.J.
    • Economic and Environmental Geology
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    • v.16 no.3
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    • pp.149-161
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    • 1983
  • Fuller's earth deposits from Miocene sedimentary sequences in Gyeong Sang-do contain up to 95% Ca-montmorillonite accompanied by cristobalite, clinoptilolite, mordenite, quartz, feldspar and X-ray amorphous material. Differential thermal analysis, infrared and electron microscopic data are given for the montmorillonite component. The ease with which the exchangeable calcium of the montmorillonite could be replaced by sodium (to give a product with properties similar to that of a bentonite) was monitored by the Atterberg liquid limit test. Some samples tested as possible binders for foundry moulding sands gave results that compared favourably with material currently being used for this application. Many of the samples also met the OCMA specifications for clays used in drilling muds.

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진공밀폐 용해법으로 제조된 $La_zCo_4Sb_{12}$ Skutterudite의 열전특성

  • Park, Gwan-Ho;Yu, Sin-Uk;Sin, Dong-Gil;Lee, Go-Eun;Jeon, Bong-Jun;Lee, U-Man;Kim, Il-Ho
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.321-321
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    • 2013
  • 열전재료는 열과 전기의 변환이 상호 가역적으로 일어나는 현상을 갖는 재료로서, 사용온도별로 여러 가지 재료가 개발되고 있다. 중온 영역에서 우수한 열전특성을 보이는 skutterudite는 격자 내에 2개의 공극을 갖고 있고 이에 적절한 원자를 충진하여 포논산란을 유도하고, PGEC(phonon-glass and electron-crystal) 개념을 적용하여 재료의 열적인 성질과 전기적인 성질을 동시에 제어함으로써 열전성능의 향상을 도모할 수 있는 재료이다. 본 연구에서는 챔버 내부 기체를 연속적으로 뽑아내어 진공도를 유지하는 방식이 아닌, 석영관을 앰플화한 진공밀폐 용해법을 사용하였다. 진공밀폐 용해법은 성분원소의 산화와 휘발을 억제하는데 있어 매우 유용한 공정이다. 용해를 통해 얻어진 잉곳을 용해와 동일한 방법으로 석영관에 밀봉하여 873 K에서 100시간 동안 진공열처리를 실시하였다. 또한, 합성된 잉곳의 기계적 특성 향상을 위해 $75{\mu}m$ 이하로 파쇄하여 진공 열간 압축 소결하였다. La가 충진된 $La_zCo_4Sb_{12}$ Skutterudites 단일상을 합성하여 La의 충진량(z)에 따른 열전특성과 전자이동특성을 조사하였다.

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On an Improved Summation Generator with 2-Bit Memory (2 비트 메모리를 갖는 개선된 합산 수열-발생기)

  • 이훈재;문상재
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.7 no.2
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    • pp.93-106
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    • 1997
  • Summation generator is a real adder generator with maximum period, near maximum linear complexity and maximum order of correlation immunity. But this generator has been analyzed by a correlation attack(a kind of known-plaintext attack), which confers carry bits from output sequences of consecutive 0's or 1's. As methods of immunizing carry-output correlation, an immunized summation generator which exclusively-ORed summation generator output with output of a stage of LFSR was proposed. But the immunized generator reuses the output of LFSR by k-bit later and does not garantees maximum period in special case. In this paper we proposed an improved summation generator with 2-bit memory and analyzed it.

Minutes of ICSH Panel Meeting Held in the Palace Hotel Noordwijk, Netherlands from 18th-23rd November, 1973

  • Belcher E.H.;Eernisse J.G.;Glass H.I.;Heimpel H.;Lewis S.M.;Mollison P.;Murphy A.E.;Naiean Y.;Szur L.;Dormer I.;Ganzoni A.;Koning J. De;Scheer K.E.
    • The Korean Journal of Nuclear Medicine
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    • v.8 no.1_2
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    • pp.63-70
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    • 1974
  • 이 논문(論文)은 1973년(年) ICSH주최로 옅린 panel에서 혈소판수명(血小板壽命) 측정법(測定法)의 표준화(標準化)에 관(關)한 토론결과(討論結果)를 기록(技錄)한 것이다. 이 prnel에서는 주(主)로 혈소판수명측정(血小板壽命測定)의 기술적(技術的)인 면(面)과 분석적(分析的)인 면(面)을 토론(討論)하고 있다. 현소판(血小板)에 방사성(放射性) 물질(物質)의 표지법(標識法)으로는 "Cohor"법(法)과 "Random"표지법(標識法)이 있으며 전자(前者)는 분석적(分析的)인 면(面)에서는 "Random" 표지법(標識法) 보다 좋으나 현재로서는 표지법(標識法)으로서 만족하지는 않다. "Random"표지법(標識法)으로는 $^{14}C$-serotonime, DEP, $^{32}P,\;^3H$$^{51}Cr$ 등(等)이 이용(利用)되고 있다. DEP는 현재 널리 사용되고 있으나 DEP는 주입후(注入後) 2주(週)까지 방사능(放射能)이 처음의 $10{\sim}15%$정도(程度)가 계속 남아있고 또한 혈소판이외(血小板以外)에도 백혈구(白血球), 적혈구등(赤血球等)에도 상당히 많이 표지(標識)되므로 혈소판(血小板)만 따로 분리(分離)해야 되는 단점이 있어서 이 panel에서는 사용하지 않는 것이 좋다고 하였다. 반면 $^{51}Cr$은 기술적(技術的)인 문제(問題)가 이미 많이 해결되어 있어 추천하고 있다. 여기서는 혈소판수명(血小板壽命) 측정법(測定法)에서 혈소판분리(血小板分離) 및 표지(標識), 채혈(採血) 및 계측(計測), data 분석법등(分析法等)에 관(關)하여 논(論)하고 있다.

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Fine Structure of the Silk Spinning Apparatus in the Spider Nurscia albofasciata (살깃자갈거미(Nurscia albofasciata) 방적장치의 미세구조)

  • Park, Eun-Ah;Moon, Myung-Jin
    • Applied Microscopy
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    • v.39 no.2
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    • pp.157-165
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    • 2009
  • Here we demonstrate the fine structural characteristics of the spigots on the cribellum and its peculiar sieve-like structure at the aspects of the functional significance. The surface of the cribellum is covered by hundred of tiny spigots which producing numerous cribellate silk fibrils. It has been known that the cribellar silk is considered as a quite different sort of catching silk with dry-adhesive properties. By our fine structural observation using the field emission scanning electron microscopy (FESEM), the titanoecid spiders have a specialized sieve-like plate just in front of the anterior spinnerets. The other types of the silk spigots were identified as follows: ampullate, pyriform and aciniform glands. Two pairs of major ampullate glands send secretory ductules to the anterior spinnerets, and another 1~2 pairs of minor ampullate glands supply the median spinnerets. In addition, the pyriform glands send ductules to the anterior spinnerets, and the aciniform glands feed silk into the median and the posterior spinnerets, respectively. Characteristically, 2 distinct types (A & B types) of the aciniform spigots were identified in this spider, and the spigots of the aciniform B type are always detected at the posterior spinneret, however sexual dimorphism for spigot is unlikely to be exhibited in this species of spider.

Ultrastructure of the Submandibular Gland in the Big White-Toothed Shrew, Crocidura lasiura (우수리땃쥐 Crocidura lasiura 악하선의 미세구조)

  • Jeong, Soon-Jeong;Lim, Do-Seun;Park, Joo-Cheol;Kim, Heung-Joong;Jeong, Je-O;Choi, Baik-Dong;Yoon, Myung-Hee;Jeong, Moon-Jin
    • Applied Microscopy
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    • v.35 no.2
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    • pp.57-64
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    • 2005
  • The ultrastructure and histochemical characteristics of the submandibular gland was examined in the big white-toothed shrew, Crocidura lasiura. A submandibular gland of Crocidura lasiura was a mixed gland composed of serous and mucous acinar cells. Secretory granules from the acini were discharged through the intercalated duct, the granular duct and the striated duct into the oral cavity. Serous and mucous acinar cells and granular duct cells had large amount of rough endoplasmic reticulum, free ribosome and prominent Golgi apparatus at the basal cytoplasm of the cell, and many granules at the apical cytoplasm. Oval type serous granules had a homogeneously pale round shape of bead at the center. Mucous granules were distinct from those of the other mammalian species having variety patterns with several dense bands into homogeneous pale matrix. A serous-like secretory granules and myelin-like body were observed in the cytoplasm and the lumen of granular duct cells. The myelin-like body is a characteristic structure only reported in the salivary glands of two shrews, Suncus murinus and C. dsinezumi. Striated duct cell had numerous well-developed mitochondria but secretory granule was not shown at all.

Growth of CdS Single Crystal by Sublimation Method (승화법에 의한 CdS 단결정 성장)

  • Jeong, T. S.;Kim, H. S.;Yu, P. Y.;Shin, Y. J.;Shin, H. K.;Kim, T. S.;Jeong, C. H.;Lee, H.;SHin, Y. S.;Kang, S. K.;Jeong, K. S.;Hong, K. J.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.3 no.2
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    • pp.125-130
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    • 1993
  • We has made 2-zone vertical electric furnace and has been grown CdS single crystal by sublimation method in crystal growth tube with tail tube without seed crystal for growth. While it has been growing, temperature difference ${\Delta}T$ of source and growth part has nearly agreed with theoritical value $14.7^{\circ}C$and experimental value $15^{\circ}C$ Then, crystal of best quality has been grown, when temperature of tail tube has been $110^{\circ}C$, in spite of quickly pulling up crystal growth tube a degree O.38mm per hour. The grown crystal have had hexagonal structure and single crystal with c-axis to length of crystal growth tube from X- ray diffraction pattern of powder method and Laue pattern of back reflection Laue method. Also, the mobility and carrier density from Hall effect measurement have been $316cm^2/V{\cdot}sec$ and $2.90{\times}10^{16}cm^{-3}$ at the room temperature, respectively.

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Users' Evaluation of Information Services in University Archives (대학기록관 이용자의 기록정보서비스 평가)

  • Jeong, Woo-cheol;Rieh, Hae-young
    • Journal of Korean Society of Archives and Records Management
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    • v.16 no.1
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    • pp.195-221
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    • 2016
  • In a situation where the recognition of archival services remains minimal, an evaluation of archival information services by users could provide a better understanding of users' practical needs and present helpful information for improved services. A service evaluation by users using questionnaires was conducted in university archives, which can similarly categorize their user groups and have frequent interactions with the users for the provision of services. Questionnaires suitable for the evaluation of university archives were developed based on the review of the evaluation tools in archival information services. From April to October 2015, 113 users' evaluation results were collected from 13 university archives. As a result of goodness of fit tests, the users' service evaluation items were categorized into four parts: Use Results, Provision of Information on Archives, Accessibility to Archives, and Interaction. For those four parts, evaluation by descriptive statistics, T-test, correlation analysis, and regression analysis were conducted. Users evaluated Interaction parts highly while they were less satisfied with Provision of Information on Archives. T-test results showed that university archives with search engines and with electronic records management systems were evaluated higher than archives without such technology. In the regression analysis, the Interaction and Provision of Information on Archives parts were found to have an influence on the Use Results part.

Study on the Characteristics of Exhaust Emissions in accordance with the Intake Manifold and Fuel Injector Maintenance of the Electronic Control Diesel Engine (전자제어 디젤엔진의 흡기 다기관 및 연료분사장치 정비에 따른 매연 배출특성에 관한 연구)

  • Kang, Hyun-Jun;Kim, Tae-Jung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.9
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    • pp.196-205
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    • 2016
  • The exhaust gas discharged by cars not only threatens the health of the human body, but also contributes to global warming, due to the resulting increase in the concentrations of ozone, fine dust and carbon dioxide. Therefore, the government has steadily implemented careful inspection systems for exhaust emissions, in order to efficiently regulate the exhaust gas of cars. Studies on reducing the exhaust emissions of automobiles have been conducted in various fields, including ones designed to reduce the generation of HC, NOx, and $CO_2$ in the exhaust emission of vehicles. However, there have been insufficient studies on the reduction of the exhaust emission for old diesel vehicles. To develop careful inspection systems for the exhaust emissions of old diesel vehicles, studies on the reduction of the exhaust emissions and improvement of power are necessary by cleaning the carbon sediment in both the intake manifold and injector. Therefore, in this study, we analyzed and compared the amounts of gas emitted when simultaneously cleaning or not cleaning the intake manifold and injector of diesel automobiles with mileages over 80,000 km and operating periods over 5 years. The experimental results showed that in the case where the intake manifold and injector were simultaneously cleaned, there was a decline of 75.2% in the gas emission compared to the cases where only the manifold or injector is cleaned. Also, it was found that simultaneously cleansing the intake manifold and injector enabled the exhaust standard to be satisfied for less than 30% within 8.5 sec.

Critical Review on Modern Change of Ecological Thought in Oriental Tradition (동양 전통 생태사상의 현대적 전환을위한 비판적 고찰 - 유학의 생태사상을 중심으로 -)

  • Han, Sung Gu;Chi, Chun-Ho
    • The Journal of Korean Philosophical History
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    • no.36
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    • pp.235-258
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    • 2013
  • People say that dichotomous way of thought in the Occident separating human from nature resulted in ecological crisis. Furthermore, it is said that surmounting Occidental way of thought is necessary to heal ecological crisis, and ecological elements in Oriental traditional philosophy could be the alternative for changing anti-ecological disposition inherent in Occidental thought. Although so-called ecology did not exist in Oriental traditional philosophy, there is room for reviewing Oriental traditional philosophy in terms of ecological elements or ecological orientation. In modern society, however, the vitality and significance of ecological elements in Oriental traditional philosophy cannot be conclusively verified. On the other hand, Occidental thought regarded as the main culprit of environmental destruction may not contain anti-ecological contents. Therefore, this study critically reviews the possibility and significance of modern change of ecological thought in Oriental tradition by raising two questions, "Is Occidental view of nature anti-ecological?" and "Is Oriental view of nature ecological?"