• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2003년도 추계학술대회 발표논문 초록집
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• pp.135-135
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• 2003

• 대한전기학회논문지
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• 제36권12호
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• pp.868-873
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• 1987

In this pater, we have proposed a synthetic main chopper circuit for the chopper controlled electric automobile. The proposed chopper circuit operates as a step-down chopper in powering mode and as a polarity reversion type chopper in regenerative braking mode. In this study, it was found that powering and regenerative braking operations using the separately excited D.C motor can be controlled continuously only by gate signals of the chopper without changing the connection of the circuit.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제18권2호
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• pp.129-139
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• 2011

We consider an optimal trading rule in this paper. We assume that the underlying asset follows a mean-reverting process and the transaction consists of one buying and one selling. To maximize the profit, we find price levels to buy low and to sell high. Associated HJB equations are used to formulate the value function. A verification theorem is provided for sufficient conditions. We conclude the paper with a numerical example.

• 한국식품조리과학회지
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• 제17권6호
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• pp.617-624
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• 2001

계육의 위생화를 위한 방사선 조사기술의 이용가능성을 검토할 목적으로 방사선 조사 계육을 대상으로 미생물학적 및 유전독성학적 안전성 평가를 실시하였다. 3kGy의 감마선 조사는 저온성 세균을 약 1.5 log cycle 정도 감소시킬 수 있었고, 일반세균도 검출한계 이하로 감소되었으며, 특히 7kGy이상의 조사로 모든 오염미생물은 완전히 사멸시킬 수 있었다. 또한 감마선 조사후 냉동저장의 병용은 육제품의 초기살균과 미생물의 생육억제에 매우 효과적임을 알 수 있었다. 유전독성학적 안전성 시험의 경우에는 감마선 조사 및 비조사 닭고기 현탁액의 S. typhimurium TA98, TA100, TA1535 및 TA1537에 대한 복귀변이 집락수를 조사한 결과, 대사활성계 도입 및 부재시 모두, 모든 시험균주에서 시험적용 농도인 0.I~8.3mg/plate의 범위에서 복귀변이 집락수의 농도 의존적인 증가 혹은 감소를 보이지 않아 감마선 조사 닭고기(10kGy)는 돌연변이원성이 없는 것으로 판단되었다. 또한 설치류 망상적혈구를 이용하여 감마선 조사된 닭고기의 염색체 이상 시험을 수행한 결과, 감마선 조사 닭고기는 시험적용 용량인 1250~2500mg/plate의 범위에서 소핵을 가진 망상 적혈구의 출현율이 음성대조군과 유의한 차이를 나타내지 않아 소핵을 유발하지 않음을 확인하여 유전독성학적 측면에서의 안전성이 확인되었다.

• KSBB Journal
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• 제14권2호
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• pp.248-254
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• 1999

본 연구에서는 디프테리아 toxin을 정제한 후 무독화하여 toxid를 생산하기 위하여 crude toxin을 2중 U.F를 통해 분자량 100.000이상의 단백질과 30.000이하의 배지 유래 단백질 및 색소를 제거한 결과 순도 1,300 Lf/mg PN의 toxin을 정제하였다. 이를 다시 DEAE-ion exehange chromatography를 통해 toxin을 정제한 후 무독화하여 순도 2,560 Lf/mg PN의 toxoid를 얻을 수 있었다. 이와 같이 생산된 디프테리아 toxoid는 동물 실험 결과 toxin으로 reversion이 발견되지 않았으며, 역가에 있어서도 crude toxin을 무독화한 후 정제한 toxoid와 비교하여 더 우수하였고 대한민국 생물학적 제제 기준에 규정된 성인용 디프테리아 백신 순도 기준 2,500 Lf/mg PN 이상에 적합하였다. 따라서 본 연구를 통해 성인용 디프테리아 백신의 생산 가능성을 확인하였다.

• Toxicological Research
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• 제14권3호
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• pp.453-457
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• 1998

In order to evaluate the mutagenic potential of Intralipidos produced by Greenmate cooperation. We performed Salmonella typhimurium reversion assay, chromosomal aberration test on chinese hamster ovarian cells and in vivo micronucleus assay using mouse bone marrow cells. In the reverse mutation test using Salmonella typhimurium TA98 and TA100, Intralipidos did not increase the number of revertant at any of the concentration tested in this study. Intralipidos did not increase the number of cells having structural or numberical chromosome aberration in cytogenetic test. In mouse micronucleus test, no significant increase were observed in the occurrence of micornucleated polychromatic erythrocytes in ICR male mice intraperitoneally administered with Intralipidos. These results indicate that Intralipidos has no genetic toxicity under these experimental conditions.

• Toxicological Research
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• 제14권3호
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• pp.427-433
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• 1998

The acute and genetic toxicity of DK1002 was subjected in this study. DK1002 which is a morphine-like new drug candidate synthesized by Dong-Kook Pharmaceutical Co. Ltd. is now under developing as a analgesics that have better drug efficacy and least addictive property. In acute toxicity study, the 50% lethal doses ($LD_{50}$) of DK1002 were determined as>2000mg/kg (p.o.), 237.0mg/kg(i.p.), 57.5mg/kg(i.v.), and 1266.9mg/kg (s.c.). And also, to study the genotoxicity of DK1002, we performed bacterial reversion assay with Salmonella typhimurium TA98, TA100, TA1535, and TA1537, and in vitro chromosomal aberration assay with Chinese hamster lung cells in the presence and absence of S-9 metabolic activation system. In vivo micronucleus assay using mouse bone marrow cells was also performed. From these results, DK1002 was revealed nonmutagenic potential in S. typhimurium TA98, TA100, TA1535, and TA537 both in the absence and presecne of metablic activation system. No clastogenicity of DK1002 was observed in chromosomal aberration assay in vitro as well as in micronucleus assay in vivo.

• 대한한방종양학회지
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• 제7권1호
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• pp.99-107
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• 2001

In the present studies, decursinol angelate, decursin isolated from Angelica gignatis radix and oil fraction of Cnidii rhizoma was analyzed by normal phase HPLC and GC/MS respectively. The standardized water extracts of Angelica gignatis radix, Cnidii rhizoma and its complex named Gung-gui-tang was tested the anti mutagenic effects by in vitro genotoxicity using Salmonella reversion assay (Ames test) and micronucleus test in chinese hamster ovary(CHO) cells. Angelica gignatis radix, Cnidii rhizoma and Gung-gui-tang was not exhibited the antimutagenic effects in the Salmonella reversion assays with or without metabolic activation. However, the micronucleus test assays, Angelica gignatis radix and Gung-gui-tang was showed the antimutagenic effects significantly. The maximum inhibition observed with Gung-gui-tang was reduced by 59% in the micronucleus test without metabolic activation. In this paper, results are presented on the availability of potential antimutagenic activity of the water extracts of Gung-gui-tang.

• 한국미생물·생명공학회지
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• 제24권1호
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• pp.105-110
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• 1996

Mugwort has been known as a traditional substitutive foodstuff and as showing a physiologically beneficial function to a human being. Therefore, effect of mugwort extract in terms of mutagenicity and desmutagenicity was investigated to berify its function. Ethanol extract from mugwort did not exhibit any mutagenicity. On the contrary, inhibitory effects of the ethanol extract were observed on mutagenicity induced by aflatoxin $B_{1}(AFB_1)$, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole(Trp-P-1), 3-amino-1-methyl-5H-pyrido[4,3-b]indole(Trp-P-2) and 2-nitroflourene(2NF) using Salmonella typhimurium reversion assay. On direct-acting mutagen(2NF, 3${\mu}$g/plate), ethanol extract showed a slight inhibitory effect of 19.7~22.9%, however on indirect-acting mutagen such as AFB1(2${\mu}$g/plate), Trp-P-1(1${\mu}$g/plate) and Trp-P-2(1${\mu}$g/plate), we observed higher inhibitory effect of 47.9~61.2%, 64.1~70.7%, 67.4~78.7%, respectively. Step-wise fractionation of the ethanol extract was done by using hexane, chloroform, ethyl acetate and water to obtain effective fraction. Among them, hexane, chloroform, and ethyl acetate fractions showed high inhibition of 63.0~80.0%, 77.5~82.1%, and 68.5~83.1%, respectively on the mutagenicity of $AFB_1$ in Sal. typhimurium TA98. Consequently, these results indicated that mugwort extract contains some compound(s) which may show desmutagenicity.

• 폴리머
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• 제25권1호
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• pp.63-70
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• 2001

대표적 가교형태 변화에 따른 유사한 stress-strain 특성을 나타내는 조건하에서 공정특성 및 전반적 물성에 미치는 영향을 조사하였다. 천연고무 기본 배합에서 촉진제나 황 공여체(sulfur donor) 증가에 따라 induction time은 길어지나, 가류속도는 빨라졌다. 가교계 변화에 따른 인장강도의 영향은 매우 적은 반면 신장율은 conventional vulcanization (CV)계에서 efficient vulcanization (EV)계로 갈수록 감소하는 경향을 보여 주었다. Blow-out이 발생하는 시간을 가교형태에 따라 비교하여 보면 CV