• 폴리머
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• 제29권2호
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• pp.161-165
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• 2005

Octamethylcyclotetrasiloxane$(D_4)$과 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane$(D_3^{MePh})$을 1,1,3,3,-tetramethyl-1,3-divinylsiloxane(MVS)과 평형중합시켜 dimethylsiloxane과 methylphenylsiloxane block unit를 갖는 $\alpha,\omega-vinyl$ poly(dimethyl-methylphenyl)siloxane prepolymer(VPMPS)를 제조하였으며 또한 $D_4$와 1,3,5-trimethyl-1,3,5-trifluoropropylcyclotrisiloxane $(D_3^{M3,F3P})$을 1,1,3,3-tetramethyldisiloxane과 평형중합시켜 dimethylsiloxane과 methyltrifluoropropyl siloxane block unit를 갖는 $\alpha,\omega-hydrogen$ poly(dimethyl-methyltrifluoropropyl)siloxane prepolymer(HPDMFS)를 제조하였다. VPMPS, HPDMFS, 열전도 필터 및 촉매를 고속교반기에 가하고 $130^{\circ}C$에서 컴파운딩하여 저경도 poly(organosiloxane) rubber를 제조하였으며 이의 가교밀도는 $115^{\circ}C$에서 oscillation rheometer를 이용하여 측정하였다. 열전도성 충전제로 구상 알루미나를 Horsfield's packing model에 따라 평균입자경의 분포를 조절하여 제조한 composite TC-POXR-2의 열전도도가 1.13 W/mK, 그리고 TC-POXR-4가 1.19 W/mK였으며 이는 단일입자경을 갖는 충전제를 가하여 제조한 경우보다 높은 열전도성을 나타내었다.

• 미생물학회지
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• 제20권1호
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• pp.11-20
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• 1982

A study was undertaken to examine the effect of curing agents on the stability, curing and segregation of R plasmid pSL100. And also the stability, transfer frequency, and recombination of its segregants obtained from curing agent treatment were studied. Ethidium bromide, acridine orange, and mitomycin-C were used as curing agent. The results obtained were as follows ; 1. The curing agent ethidium bromide, acridine orange, and mitomycin-C were not effective for curing the multiple antibiotic resistant determinant of pSL100 in Salmonella typhimurium and Escherichia coli. However, they induced plasmid segregation with high frequency in S.typhimuruim LT-2strains. TcApSmCm, TcSmCmKm, TcApCm, TcAp, TcKm, Tc segregants were obtained. 2. The resistant markers of the segregents were transferred to S.typhimurium LT-2 strains with high frequencies whereas they were transferred to E.coli K-12 only with low frequencies. 3. The transconjugants obtained from conjugation between two different S.typhimurium segregants were similar to the phenotype of the original R factor pSL100 and the resistant markers were transferred to the S.typhimurium LT-2 or E.coli strain with equal frequencies, indicating that they are recombinants. 4. The transconjugants obtained from conjugation between pSL100 segrgants and pKM101, or pBR322 possessed the resistant markers of the two parental plasmids and they were transferred to both S.typhimurium and E.coli K-12 strains with the same frequencies and maintained stably, suggesting that they are also recombinants. 5. The recombinant pSL100 could be also obtained in rec A-strains of E.coli, suggesting that the gene function of rec A is required for the recombination of pSL100 segregants in E.coli.

• 대한임상검사과학회지
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• 제44권3호
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• pp.103-111
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• 2012

Low-Density Lipoprotein cholesterol (LDLC) is the most important marker for the treatment of hyperlipidemia in NCEP-ATP III(National Cholesterol Education Program-Adult Treatment Panel III) guideline. Therefore, LDL cholesterol is pathologically meaningful, accurate measurement should be a top priority. Currently, LDLC is directly measured in most cases, but, the estimate is still used in mass health examination or screening test. This study is about the comparison of LDL-Cholesterol direct measurement with the estimate using various formula (Friedewald: [LDL-F=TC-HDL-TG/5], Nakajima: [LDL-N=TC-HDL-TG/4], Hattori: [LDL-H =0.94TC-0.94HDL-0.19TG], Puavilai: [LDL-P=TC-HDL-TG/6], Carvalho: [LDL-C=3(TC-HDL)/4]) for calculating more accurate value. We analyzed total cholesterol (TC), try-glyceride (TG), high-density lipoprotein cholesterol (HDLC), and LDLC levels of 210 subjects between June and November in 2011. Until now, the Friedewald formula is the most commonly used estimate for the LDLC. When Friedewald formula was applied, the correlation coefficient (r) was 0.940, showing high correlation. But, the result of the direct method was significantly different, compared with those of the Friedewald formula in triglyceride levels ${\geq}400mg/dL$(p<0.05). There was the highest correlation when we used LDL-P formula(r=0.947) in triglyceride levels <400 mg/dl. Also there was the lowest mean difference regardless of triglyceride level. Therefore, the study showed that TG/6 is more precise means of calculation than TG/5. On the other hand, the calculation of LDL-Cholesterol was underestimated, compared with direct measurement. It is necessary to have more data and modified Friedewald formula should be used for the accurate calculation.

• 대한임상검사과학회지
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• 제37권3호
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• pp.185-189
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• 2005

Lipids such as total cholesterol (TC), high density lipoprotein-cholesterol (HDL-C) and high sensitivity C-reactive protein (hs-CRP) are known as good risk factors for coronary artery diseases caused by arthrosclerosis. We measured the serum concentrations of hs-CRP, TC, and HDL-C of 6,128 persons who underwent medical examinations in the Health Screening Center at Kangbuk Samsung Hospital. We classified the subjects into normotensive and hypertensive groups according to the blood pressure measured. We investigated whether there was a difference of hs-CRP and lipids between the normotensive and hypertensive groups. There was significant difference of TC, TC/HDL-C ratio, and hs-CRP concentration between the normotensive and hypertensive groups in both men and women, but there was no significant difference of HDL-C concentration between two groups. Our results indicated that the concentrations of hs-CRP and lipids were higher in patients with hypertension and confirmed the usefulness of lipids and hs-CRP in predicting the risk for coronary artery diseases.

• 대한미생물학회지
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• 제5권1호
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• pp.1-8
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• 1970

This report is to observe the rate of multiple resistance to various antibiotics among staphylococcus aureus and E. coli which were isolated with high frequency at our department during 1969. 1. One hundred fifty two strains(20.6%) resistant to four antibiotics multiple resistant was the highest incidence among 739 strains of Staphylococcus aureus. 2. Regarding the multiple antibiotic resistant of Staphylococcus aureus, 75strains(10.1%) to SA. PC. TC the three antibiotics resistant, have been observed, with the highest incidence, and next to this, 69 strains(9.3%) to SA. PC. SM. TC the four autibiotics resistant, and 68 strains(9.2%) to SA. PC. SM. CM. TC. SM. the six antibiotics resistant, have been observed in descending order. 3. The case of one hundred twenty seven strains(28.0%) of the six antibiotic multiple resistant among 454 strains of Escherchia coli was the highest incidence. 4. Concerning the multiple antibiotic resistant of Escherichia coli, 70 strains(l5.4%) to SA. SM. CM. TC. EM. FD. the six antibiotics resistant, have been observed, with the highest incidence, and next to this, 59 strains(l3.0%) to SA. SM. CM. TC. EM. FD. AC the seven antibiotics resistant, and 42 strains(9.3%) to SA. SM. CM. TC. EM. FD. KM. AC the eight antibiotics resistant have been observed in descending order.

• 한국가축번식학회지
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• 제20권1호
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• pp.63-69
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• 1996

Bovine immature oocytes cultured for various times in TC-199 medium were inseminated with frozne-thawed spermatozoa in TC-199 medium supplemented with caffeine(5mM) and heparin(10$\mu\textrm{g}$/ml). Sperm penetraton was possible in oocytes at any stage of maturation, but penetration rates were lower in oocytes inseminated 0~16h (60~76%) than 20h (98%) after culture. Formation of male and female pronuclei were first observed in oocytes inseminated 8h after cultrue. Formation of male and female pronuclei were first observed in oocytes inseminated 8h after culture. The proportions of polyspermy were high(50~76%) in oocytes inseminated at any stage of maturation. Sperm penetration into oocytes at the GV stage started at 8h after insemination and the penetration rates gradually increased as time after insemination proceeds. The proportion(35%) of oocytes matured beyond metaphase-II 20h after sperm-oocytes incubation was low. When oocytes were incubated without spermatozoa in TC-199 medium, maturation rates were significantly higher (P<0.001) in those without(45 and 84% for 16 and 20 h) than with (0 and 36% for 16 and 20 h) caffeine and heparin. These results indicate that TC-199 medium with caffeine and heparin is not suitable for maturation and fertilization of immature oocytes and may inhibit male pronuclear formation in the cytoplasm.

• 대한수의학회지
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• 제16권2호
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• pp.159-163
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• 1976

One hundred and sixty one Escherichia coli strains isolated from 24 swine (11 swine fed with feedstuffs containing 7.5mg/kg of tetracycline and 13 swine not received antibiotic) were studied for the drug resistance and distribution of R factors. About 42 per cent of E. coli strains isolated from pigs of a herd fed with tetracycline (TC)-containing feeds were resistant to TC, streptomycin(SM), sulfisomidine(SA), ampicillin (AP) and kanamycin (KM), alone or in combination thereof, but none of the swine not receiving antibiotic containing feedstuffs excreted E. coli resistant to these drugs, Among resistant strains, 18.2% were found to be singly resistant to TC, whereas 81.8% were resistant to two or more antibiotics. The most common pattern was the triple resistant to TC, SM and SA(30.3%), and follolwed by double ones to TC and SM(24.2%). About one half of resistant strains carried R factors which were tranferable to the recipients by conjugation. In spite of feeding with feedstuffs containing only TC, high incidences of multiple resistance and R factors were observed in the E. coli isolated from these swine.

• 한국통신학회논문지
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• 제30권1C호
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• pp.18-24
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• 2005

본 논문에서는 고속의 데이터 전송을 위해 APSK (Amplitude/Phase Shift Keying) 신호 기반 DUSTM(Differentail Unitary Space-Time Modulation) 기법과 트렐리스 코드를 결합하여 새로운 TC-DUSTM (Trellis Coded DUSTM) 기법을 제안한다. 특히, APSK 신호 기반 TC-DUSTM (trellis coded DUSTM) 기법에 적합한 트렐리스 코드 설계 방법을 제안한다. 모의실험을 통해 제안된 TC-DUSTM 기법은 높은 전송률에서 기존의 PSK 신호 기반 TC-DUSTM 기법에 비하여 비트 오류 확률 성능이 향상됨을 알 수 있다. 또한, 제안된 기법이 빠른 페이딩 채널 환경에서 발생되는 차동 기법의 irreducible error를 효율적으로 줄일 수 있음을 모의실험을 통하여 확인할 수 있다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.13-15
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• 1999

A Josephson sampler circuit using high-Tc superconductor (HTS) ramp-edge junctions has been designed, fabricated, and experimentally tested. It consists of five ramp-edge junctions with a stacked groundplane and is based on single-flux-quantum (SFQ) operations. The sampler was used to measure current waveforms at picosecond and microampere resolutions. We are developing a system based on the sampler for measuring the current waveform in a room-temperature sample. And measuring current flowing through wiring in a semiconductor large-scale integrated circuit is a promising application for the HTS sampler system.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2000년도 KIASC Conference 2000 / 2000년도 학술대회 논문집
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• pp.97-100
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• 2000

Superconducting power cable is one of the most promising energy application of high-Tc superconductors (HTS). Thus, we investigated previously the characteristics on electrical and mechanical Bi-2223 Ag sheathed tape. And a prototype HTS cable have been designed, constructed and tested. The result shows that the transport current of HTS cable (1, 19-filament) in LN2 was 116[A], 240[A], respectively. And AC loss of HTS cable(19-filament) was 1.7 [W/m] in 240 [A] loading.