• Bulletin of the Korean Mathematical Society
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• v.22 no.2
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• pp.121-126
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• 1985

D.K. Harrison [5] has shown that if R and S are fields of characteristic different from 2, then two Witt rings W(R) and W(S) are isomorphic if and only if W(R)/I(R)$^{3}$ and W(S)/I(S)$^{3}$ are isomorphic where I(R) and I(S) denote the fundamental ideals of W(R) and W(S) respectively. In [1], J.K. Arason and A. Pfister proved a corresponding result when the characteristics of R and S are 2, and, in [9], K.I. Mandelberg proved the result when R and S are commutative semi-local rings having 2 a unit. In this paper, we prove the result when R and S are 2-fold full rings. Throughout this paper, unless otherwise specified, we assume that R is a commutative ring having 2 a unit. A quadratic space (V, B, .phi.) over R is a finitely generated projective R-module V with a symmetric bilinear mapping B: V*V.rarw.R which is nondegenerate (i.e., the natural mapping V.rarw.Ho $m_{R}$ (V, R) induced by B is an isomorphism), and with a quadratic mapping .phi.:V.rarw.R such that B(x,y)=(.phi.(x+y)-.phi.(x)-.phi.(y))/2 and .phi.(rx)= $r^{2}$.phi.(x) for all x, y in V and r in R. We denote the group of multiplicative units of R by U(R). If (V, B, .phi.) is a free rank n quadratic space over R with an orthogonal basis { $x_{1}$, .., $x_{n}$}, we will write < $a_{1}$,.., $a_{n}$> for (V, B, .phi.) where the $a_{i}$=.phi.( $x_{i}$) are in U(R), and denote the space by the table [ $a_{ij}$ ] where $a_{ij}$ =B( $x_{i}$, $x_{j}$). In the case n=2 and B( $x_{1}$, $x_{2}$)=1/2, we reserve the notation [ $a_{11}$, $a_{22}$] for the space.the space.e.e.e.

• Journal of Life Science
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• v.9 no.1
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• pp.106-110
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• 1999

Lipopolysaccharide(LPS) from Vibrio vulnificus was purified, the fatty acid composition was analyzed, and Limulus gelation activity and lethal toxic activity were tested in order to investigate the cause of cytotoxicity by V. vutnificus. These results were compared to those of Escherichia coli LPS and Salmonella typhimurium LPS. LPS from V. vulnificus had a different fatty acid composition from those of E coli and S. typhimurium. The major fatty arid from each LPS was lauric acid for E. coli, rapric acid for S. typhimurium, and myristic acid for V. vulnificus. The Limulus gelation activities of three LPSs were the same(0.1ng/ml) and the lethal toxicity in BALB/c mouse of V vulnificus LPS was similar to those of E. coli LPS and S. typhimurium LPS. Such factor as exotoxin need to be considered to be the cause of cytotoxicity by V. vulnificus LPS.

• Journal of Food Hygiene and Safety
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• v.35 no.1
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• pp.37-44
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• 2020

This study investigated the probability of foodborne illness caused by raw oyster consumption contaminated with high risk Vibrio species such as V. vulnificus and V. cholerae. Eighty-eight raw oyster samples were collected from the south coast, west coast and Seoul areas, and examined for the prevalence of high risk Vibrio species. The growth patterns of V. vulnificus and V. cholerae in raw oysters were evaluated, and consumption frequency and amounts for raw oyster were investigated from a Korean National Health and Nutrition Examination Survey. With the collected data, a risk assessment simulation was conducted to estimate the probability of foodborne illness caused by intake of raw oysters, using @RISK. Of 88 raw oysters, there were no V. vulnificus- or V. cholerae-positive samples. Thus, initial contamination levels of Vibrio species in raw oysters were estimated by the statistical methods developed by Vose and Sanaa, and the estimated value for the both Vibrio spp. was -3.6 Log CFU/g. In raw oyster, cell counts of V. vulnificus and V. cholerae remained unchanged. The incidence of raw oyster consumers was 0.35%, and the appropriate probabilistic distribution for the consumption amounts was the exponential distribution. A risk assessment simulation model was developed with the collected data, and the probability of the foodborne illness caused by the consumption of raw oyster was 9.08×10^-15 for V. vulnificus and 8.16×10^-13 for V. cholerae. Consumption frequency was the first factor, influencing the probability of foodborne illness.

• Journal of Korean Society of Forest Science
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• v.75 no.1
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• pp.38-45
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• 1986

This study was designed to investigate the karyotype analysis of Juniperus chinensis and its seven varieties, and P. densiflora and P. densiflora for. multicaulis. Following results were obtained. 1. Three varieties, J. chinensis v. kaizuka, J. chinensis v. aureo-variegata and J. chinensis v. procumbens are turned out as tetraploids. 2. Varieties having many long chromosomes and long mean relative length of chromosomes are J. chinensis and J. chinensis v. aureo-globosa, while varieties having short chromosomes are J. chinensis v. horizontalis and J. chinensis v. globosa. 3. Varieties with high mean ratio of long arm length to short arm are J. chinensis v. globosa and J. chinensis v. kaizuka, while a variety with the low mean ratio is J. chinensis v. aureo-globosa. 4. When chromosomes are arranged according to the total length, the most similar variety with J. chinensis was J. chinensis v. sargentii, J. chinensis v. horizontalis, J. chinensis v. globosa and J. chinensis v. aureo-globosa, while the least similar one was J. chinensis v. procumbens. 5. Pinus densiflora for. multicaulis has shorter mean relative length of chromosome than P. densiflora, while the arm ratio of the former is higher than the latter. 6. When chromosomes are arranged according to the total length, six chromosomes showed the same order between the two varieties. 7. P. densiflora for. multicaulis has many chromosomes with secondary constriction.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.233-234
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• 2008

• Journal of the korean veterinary medical association
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• v.32 no.8
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• pp.535-539
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• 1996

국제양돈수의학회(International Pig Veterinary Society ; I.P.V.S) 제14차 총회 및 학술대회가 1996년 7월 7일부터 11일까지 이태리 중북부의 대학도시 볼로냐(Bologna, Italy)에서 개최되었다. I.P.V.S.는 1969년에 영국의 캠브리지 (Cambridge, United Kingdom)에서 창립된 이래 1996년 현재 53개 회원국 1,700 여명의 회원을 확보하고 있으며, 세계 각국의 양돈과 수의학에 관심을 가지고 있는 학자, 생산자 그리고 관련업계 인사들의 학술$\cdot$기술 정보교류와 협력을 목적으로 매 2년마다 세계 주요도시를 순회 하면서 개최되고 있다. 앞으로 2년후(1998년도)에는 I.P.V.S.의 탄생국인 영국의 버밍햄(Birmingham, United Kingdom)에서 제 15차 총회 및 학술대회를 개최할 예정이며 2000년대에는 시드니 올림픽과 때를 맞추어 호주의 멜보른(Melboume, Australia)에서 제16차 총회를 개최하기로 결정되어 있다. 금년(1996년도) I.P.V.S 총회에는 우리나라에서 30개 기관/업체로부터 50여명이 참여한 바 있으며 총 27편 (구두 9편, 포스터 18편)의 학술논문을 발표하는 등 눈부신 활약을 보인 바 있다. 금년도 I.P.V.S. 총회의 특징은 돼지의 전염성 질병중 근래에 우리나라에서도 문제시 되고 있는 '돼지 생식기 호흡기 중후군 (Porcine Reproductive and Respiratory Syndrome ; PRRS)'이 세계적인 관심의 대상이었으며, 이태리 양돈병리축산학회 (Societa Italiana di Patologia ed Allevamento dei Suini ; S.I.P.A.S) 주관으로 '돼지 적리 (Swine Dysentery)'에 관한 Satellite Symposium이 개최되었다는 점이다. WTO 이래 어려워지고만 있는 우리나라 축산업 분야중 그래도 비젼이 보이는 양돈산업과 관련하여, I.P.V.S.를 통하여 우리나라 수의업무의 세계화의 길을 찾아보고자, 1 국제양돈수의학회(I.P.V.S)의 역사 (양돈과 수의업무 전문가의 새로운 만남의 장), 2 I.P.V.S.에의 참여(제13차 방콕대회), 3 한국 수의사의 활약(제14차 볼로냐대회), 4 세계화의 길(제15차 버밍햄대회, 제16차 멜보른대회), 5 국내양돈의 문제와 우리가 해야할 일(수의업무 세계화의 길을 찾자)등의 순으로 적어보고자 한다.

• Journal of the Korean Chemical Society
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• v.17 no.6
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• pp.428-433
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• 1973

The quantitative separations of a mixture containing equal amount of each anion such as Si(IV), As(V), P(V), S(VI), W(VI) and Cr(VI) are carried out by the elution through 20${\times}3.14cm^2$ column of anion exchange resin, Dowex 1${\times}$8. The eluents are a mixture of 0.07 M hydrochloric acid and 0.03 M sodium chloride (pH = 1.30) for Si(IV), As(V) and P(V) species, a mixture of 0.6 M sodium chloride and 0.3 M sodium hydroxide for S(VI), W(VI) and Cr(VI) species, and 0.1 N sodium sulfite (pH = 3.48) for P(V) and As(V) species. The subsidiary anions in a standard mixture such as Si(IV), As(V), S(VI), P(V) and W(VI) are separated together from large amount of Fe(III) by the elution through 30cm${\times}3.14cm^2$ column of the resin, Dowex${\times}$50w${\times}$12, using a mixture of 0.1 M sodium nitrate and 2 percent dimethylsulfoxide aqueous solution as an eluent. Si(IV), As(V), S(VI), P(V) and W(VI) eluted together are separated quantitatively under the same conditions as in the separations of the anion mixture. By the conditions obtained in the separations of the standard mixture, Fe(III) and all of the subsidiary anions in steel are quantitatively separated.

• Korean Journal of Animal Reproduction
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• v.23 no.4
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• pp.281-291
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• 1999

The objective of this study was to optimize the freezing/thawing method of in vitro produced Hanwoo blastocysts. Day 7 blastocysts after IVF were vitrified using EFS40 (40% ethylene glycol, 18% ficoll, 0.3 M sucrose and 10% FBS added m-DPBS) as a freezing solution and electron microscope (EM) grid (V-G) or straw (V-S) as an embryo container. In both method, freezing/thawing were treated by 2-step, treatment time was required in V-G method and V-S method, for 2 min / 3 min and 3.5 min / 10 min, respectively. Embryo survival was assessed as re-expanded and hatched rates at 24 h and 48 h after warming, respectively. The results obtained in these experiments were summarized as follows: when the effect of exposure in vitrification solution and chilling injury from freezing procedure on in vitro produced expanded blastocysts were examined, at 24 h after warming, embryo survival in exposure group (100.0%) was not different compared to that in control group (100.0%), although those results were significantly different with two vitrified groups (V-G: 87.8, V-S: 77.8%) (P＜0.001). However, at 48 h after warming, hatched rates of V-G group (67.8%) were significantly higher than those of V-S group (53.3%) (P＜0.05). In addition, this hatched rate in V-G group was not different with that in exposure group (73.3%). When the effects of embryo developmental stage (early, expanded and early hatching blastocysts) and embryo container (EM grid and straw) to the in vitro survival of vitrified-warmed day 7 Hanwoo blastocysts were simultaneously examined, fast developed embryos were indicated the better resistance to freezing than delayed developed one, irrespective of embryo containers (early; 57.1 ＆ 24.4%, expanded; 84.7 ＆ 60.6%, early hatching; 91.7 ＆ 80.0%) (P＜0.001). Especially, in expanded and early hatching blastocysts, embryo survival of V-G group (67.8, 95.0%) was significantly higher than those of V-S group (53.0, 65.0%) at 48 h post warming, respectively (P＜0.05, P＜0.001). Therefore, this study indicates that Hanwoo blastocysts can be cryopreserved more simple, efficient and successful by vitrification method using EM grid.

• Nuclear industry
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• v.29 no.7
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• pp.58-60
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• 2009

시험 검사 인증 기술 컨설팅 분야의 세계적인 서비스 기업인 T$\ddot{U}$V S$\ddot{U}$D 그룹의 한국 법인인 T$\ddot{U}$V S$\ddot{U}$D Korea가 최근 원자력 기기 및 시스템 설계 엔지니어링 기업인 (주)GNEC를 인수, 합병하면서 국내 원자력 시장에 성큼 진출하는 한편 우리나라 원자력사업의 해외 시장 진출을 적극적으로 도울 계획을 세우고 있다. 라이너 블록 사장은 GNEC 인수 후 기자회견을 통해 "원자력 기기 및 설계, 교육 및 엔지니어링 서비스 등 관련 기술 지원에 앞장서 국내 에너지 산업의 활성화에 앞장서는 것을 물론 국내 원자력 산업의 해외 진출을 지원하면서 중국, 인도 및 중국 등 아시아 시장에 적극 진출할 것" 이라고 말하고 "원전 관련 기술을 갖고 있는 다른 기업에 대해서도 향후 인수 합병(M&A)에 나설 계획"이라고 밝혔다. T$\ddot{U}$V S$\ddot{U}$D Korea가 GNEC 인수를 마무리한 시점인 지난 10월 19일, 한강이 내려다보이는 여의도 대한생명 63빌딩 12층 T$\ddot{U}$V S$\ddot{U}$D Korea 사장실에서 라이너 블록 사장을 만났다. 인터뷰 자리에는 이번 GNEC 합병에 큰 역할을 한 김두일 T$\ddot{U}$V S$\ddot{U}$D 고문이 배석하여 인터뷰를 도왔다.

• JSTS:Journal of Semiconductor Technology and Science
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• v.9 no.2
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• pp.117-123
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• 2009

$Pb_{x}Cd_{1-x}S$ films are prepared in the composition range of 0.05${\leq}x{\leq}$0.25, using a chemical bath deposition growth technique under optimum conditions amide at realizing good photo response. The x-ray diffraction results show that the films are of PbS-CdS composite with individual CdS and PbS planes. The films exhibit two direct band gaps, 2.4 eV attributed to CdS, while the other varies continuously from 2.4 eV to 1.3 eV. The films surface morphology is smooth with crystallite, whose grain size increases with increasing mole fraction (x). The decrease in band gap with increase in lead concentration suggests inter-metallic compound of PbS (Eg=0.41 eV) with CdS (Eg=2.4 eV)