• Title/Summary/Keyword: 철(II)

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A Study on Internal Surface Finishing of Tube Using Magnetic Assisted Polishing (원통내면의 자기연마에 관한 연구)

  • 이용철;박상길;송치성;이종렬;이득우
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.05a
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    • pp.792-795
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    • 2000
  • The magnetic assisted finishing thought to be one of the potential methods for the automatic polishing process. In this study, magnetic assisted finishing process was experimentally attempted to polish the intrnal surface of the cylindrical tube. The newly developed magnetic tool was used, and its polishing performance exmined. From the experimental results, it is found that i ) the newly developed tool is suitable for intrnal surface finishing of the tube. ii ) the surface roughness of 0.9~1${\mu}{\textrm}{m}$Rmax before polishing is improved to the value of 0.2 ${\mu}{\textrm}{m}$Rmax in the finishing experiment of stainless steel STS3602L tube in 6 minutes finishing time.

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Influencing Factor on Thermal Coefficient of Concrete due to Aggregate Types (골재종류가 콘크리트의 열팽창계수에 미치는 영향)

  • 김진철;양성철;김남호
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.05a
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    • pp.249-254
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    • 2003
  • The thermal coefficient of concrete is measured using dilatometer (AASHTO TP60) and strain gage. Testing parameters such as six different coarse aggregate types, cycles of warming and cooling, specimen shape and measurement types were investigated to evaluate the influencing factors for thermal coefficient of concrete. According to experimental results, the thermal coefficient of concrete made with crushed aggregate showed 9.2 -10.$\mu\varepsilon/^{\circ}C$, , however recycled coarse aggregate classified type II showed a little increasing in comparison with crushed aggregate. The thermal coefficient of concrete made with recycled aggregate was reduced 0.2-0.4$\mu\varepsilon/^{\circ}C$, under temperature cycles. However, specimen shapes were revealed as mainly affecting factors on the thermal coefficient of concrete. Finally the thermal coefficient value determined by the dilatometer device was shown to be similar to the value from PML 60.

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OSTEOMYELITIS OF THE MANDIBLE ASSOCIATED WITH OSTEOPETROSIS (하악골 골수염이 동반된 전신적 골화석증)

  • Lee, Jong-Ho;Jeong, Jong-Cheol;Seo, Ku-Jong;Jeong, Joong-Jae
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.14 no.4
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    • pp.269-274
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    • 1992
  • Osteopetrosis is a rare skeletal disease of unknown etiology. Osteomyelitic changes in the jaw bones are frequently seen in this disease, especially in the mandible and may follow upon tooth extraction. A case is reported of a 31-year-old male who was seen because of intraorally exposed bony spicule and chronic dull pain. Radiographic and haematological investigations led to the diagnosis of osteopeirosis with osteomyelitis. The striking radiologic findings were pathologic mandibular fracture and generalized skeletal thickening. The present case could be grouped under the benign form, type II osteopetrosis. With the conservative and minimally invasive modes of treatment including administration of penicillin G sodium, curettage and closed reduction, we could successfully manage the osteomyelitis and pathologic fracture associated osteopetrosis.

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Iron(II) Porphyrin계 화합물을 포함한 Polysulfone 막에서의 $O_2,N_2$ 투과특성에 관한 연구

  • 신우철;김현준;유병수;홍석인
    • Proceedings of the Membrane Society of Korea Conference
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    • 1994.04a
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    • pp.47-48
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    • 1994
  • 분리막을 이용한 기체의 분리는 각 기체의 막에 대한 투과도 차이에 의해 분리하는 방법으로 에너지 소비가 적고, 열 안정성이 약한 물질을 저온에서 분리할 수 있는 장점, 좁은 공간에서도 이용할 수 있다는 점 등으로 미루어 볼때 기존 공정에 대한 새로운 경쟁자로서 그 가능성이 한층 커지고 있다. 분리막의 특성은 투과도(Permeability)와 선택투과도(Permselectivity)에 의해 결정되고 이 두가지 특성을 모두 높이기 위한 연구가 활발히 진행되고 있다. 그 연구방향은 (1) 새로운 고분자의 합성 및 고분자의 개질 (2) 복합재료의 개잘 (3) 액정 (4) 촉진수송법 등으로 나눠질수 있다. 이 중 촉진수송(Facilitated Transport)이란 특정한 기체와 가역적 친화력 또는 흡착력을 갖는 운반체(ㅊㅁㄱ\ulcornerㄱ)를 액체나 고체막에 분산시켜 원하는 특정 기체만을 선택적으로 수용하는 것을 말한다.

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Design of High Speed Modular Multiplication Using Hybrid Adder (Hybrid 가산기를 이용한 고속 모듈러 곱셈기의 설계)

  • Lee, Jae-Chul;Lim, Kwon-Mook;Kang, Min-Sup
    • Proceedings of the Korea Information Processing Society Conference
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    • 2000.10a
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    • pp.849-852
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    • 2000
  • 본 논문에서는 RSA 암호 시스템의 Montgomery 모듈러 곱셈 알고리듬을 개선한 고속 모듈러 곱셈 알고리듬을 제안하고, Hybrid 구조의 가산기를 사용한 고속 모듈러 곱셈 알고리듬의 설계에 관하여 기술한다. 기존 Montgomery 알고리듬에서는 부분합계산시 2번의 덧셈연산이 요구되지만 제안된 방법에서는 단지 1번의 덧셈 연산으로 부분 합을 계산할 수 있다. 또한 덧셈 연산 속도를 향상시키기 위하여 Hybrid 구조의 가산기를 제안한다. Hybrid 가산기는 기존의 CLA(Carry Look-ahad Adder)와 CSA(Carry Select Adder)알고리듬을 혼합한 구조를 기본으로 하고 있다. 제안된 고속 모듈러 곰셈기는 VHDL(VHSIC Hardware Description Language)을 이용하여 모델링하였고, $Synopsys^{TM}$사의 Design Analyzer를 이용하여 논리합성(Altera 10K lib. 이용)을 수행하였다. 성능 분석을 위하여 Altera MAX+ PLUS II 상에서 타이밍 시뮬레이션을 수행하였고, 실험을 통하여 제안한 방법의 효율성을 입증하였다.

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STUDIES ON ACCELERATING GENERATION OF TOBACCO (MCOTIAWA TABACUM L.) UTILIZING THE PHYTOTRON (연초(Nicotiana tabacum L.) 세대촉진에 관한 연구 I. 황색종 연초품종의 세대촉진)

  • 정윤화;정석훈;금완수;최상수;이승철
    • Journal of the Korean Society of Tobacco Science
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    • v.7 no.1
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    • pp.25-31
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    • 1985
  • For shortening the tobacco breeding cycle, seedlings with 6, 8 and II leaves of 2 flue.cured tobacco varieties, day. neutral type and photoperiod-sensitive type, were grown in controlled-environment room (CER), programmed for temperature of $18^{\circ}C$ and 8.hour day period of 30 klux, for 20, 30 and 40 days. All of plants of day.neutral type variety treated in CER, regardless of seedling stage and duration, flowered earlier than the untreated plants. In the 6.leaf seedlings stage of photoperiod-sensitive type variety, plants treated for 20 and 30 days in CER did not accelerate the flowering. the tobacco plants, treated with low temperature for 20 days at 8.leaf seedling stage, flowered earlier in comparison with. the other treatment.

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Cytotoxicity Test of Pokeweed Antiviral Protein Type I Gene by Using Yeast Expression System (효모 발현 시스템을 이용 PAP(Pokeweed Antiviral Protein) 유전자의 세포독성 연구)

  • 김선원;박성원;강신웅;이영기;이종철;최순용;이청호
    • Journal of the Korean Society of Tobacco Science
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    • v.23 no.2
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    • pp.133-140
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    • 2001
  • PAP-I cDNA was synthesized from total RNA of Phytolacca americana leaves by RT-PCR, and then subcloned to recombinant vector pBluescript II SK-. Using PCR with primers designed in our laboratory, we could get the 9 deletion mutant PAP-I cDNA fragments. The first of the fragments was deleted by 66bp from immature N-terminal and then the rest were deleted by 90bp sequentially. Sequentially deletion mutant PAP-I cDNAs were inserted to pAc55M, on down-stream of gall promoter. Recombinant pAc55M was transformed to yeast cells, psy1 and the cells were spreaded on SC_urn-/glucose plate media. Colonies on SC_ura-/glucose plate were streaked on the same position of SC_ura-/glucose and SC_ura-/galactose plate, and we selected colonies growing on both plates, which carry non-cytotoxic deleted mutant PAP-I cDNA. We selected 4 deletion mutant PAP-I cDNAs which have not cytotoxicity.

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Studies on the Components of Sambucus Species II -pharmacological studies on the extracts from the leaves of Sambucus latipinna var. coreana- (Sambucus속(屬) 식물(植物)의 성분연구(成分硏究) [제2보](第二報) -접골목엽(接骨木葉) 추출물(抽出物)의 약리학적(藥理學的)인 고찰(考察)-)

  • Lee, Soon-Chul;Ahn, Young-Ran;Kim, Hak-Seang;Kim, Jae-Wan
    • Journal of Pharmaceutical Investigation
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    • v.6 no.3
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    • pp.70-76
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    • 1976
  • Pharmacological studies on the water extracts of Sambbcus latipnna var. coreana have confirmed that there are: 1) Remarkable sedative actions in preteated mice with C.N.B (caffeine and sodium benzoate) by the administration of intraperitoneal injection. 2) Antihypertensive actions in rabbits intraperitoneally injected with the extract, and as antihypertensive components, rutin, and crystal A (m.p. $250{\sim}254^{\circ}$, Liberman-Buchard's reaction, positive) were isolated from Sambucus latipinna var. coreana. 3) Marked diuretic actions in mice intramuscular injection with the dose of 600mg/kg.

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A Study on the Preparation of Thin-Film Composite Membrane with Polyethersulfone Supporting Membrane (역삼투 복합막 제조(II) 폴리에테르설폰막의 제조와 복합막 제조에 관한 연구)

  • 이동진;민병렬;이병철;송희열
    • Membrane Journal
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    • v.4 no.1
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    • pp.46-56
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    • 1994
  • The performane of prepared Thin-Film Composite membrane depends on supporting membrane, concentration of monomers, dipping time of supporting membrane into monomer solution, reachon time between monomers, curing temperature and time and posttreatment. This study was conducted for searching the optimal condition for making the composite membrane. For this purpose, supporting membrane and composite membrane was made under various condition and at each step were tested.

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OTOTOXICITY ASSOCIATED WITH CISPLATIN (Cisplastin 투여에 따른 청력변화)

  • 이종철;고의경;왕수건;전경명
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1987.05a
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    • pp.5.1-5
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    • 1987
  • Cisplatin (cis-dichlorodiamine platinum II)은 두경부 및 고환의 악성종양에 아주 효과적이라고 알려져 있다. 그러나 이 약물은 이독성 및 신독성이 이미 임상연구로 발표되어 있으며 신독성은 cisplatin 투여시 이뇨제 및 수액의 투여로 그 정도 및 빈도는 감소시킬 수 있지만 이독성은 감소시키지 못한다. Cisplatin에 의한 이독성은 보통 자각적으로 나타나지 않는데 이는 내이 와우각의 회전중 저부에서 일어나며 또한 외유모세포의 최외측열에서 일어난다고 동물실험에서 밝혀진 바 있다. 본 교실에서는 cisplatin의 이독성을 관찰하기 위하여 1회에 cisplatin 60~80 mg/$m^2$을 투여한 두경부 악성종양환자를 대상으로 투여전후의 청력을 비교 관찰하였다. 1) 청력은 대부분 10㏈ 이내의 손실례가 많았다. 2) 최대청력손실이 있는 주파수는 8KHz, 4KHz의 순으로 주로 고음역에서 발생하였다. 3) 신독성은 전례에서 관찰되지 않았다.

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