• Journal of Preventive Medicine and Public Health
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• 제36권1호
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• pp.77-84
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• 2003

Objectives : Two related cases of Hemolytic-Uremic Syndrome (HUS) were reported to the Korea National Institute of Health in May, 2001. Shiga toxin 2 genes were detected in both stool samples. We suspected an enterohemorrhagic Escherichia coli (EHEC) infection as the cause of the HUS, and conducted an investigation to find the source of the infection and its route of transmission. Methods : We peformed case investigations on these two related HUS cases, and obtained interviews and rectal swabs form the family members and other close contacts. Additionally, we peformed rectal swabs on the cattle raised by the household of the index patient. Results : We found a 20 month old index patient and a 6 year-old cousin had developed HUS, where there had been a 2 day history of contact with the index, and bacteriological examinations for these two patients revealed, indistinguishably, the same E. coli O171. The grandmother of the index patient was found to be asymptomatic, but E. coli O26 was isolated. We also found a probable case in the mother of the cousin. She reported a history of contact with the index, and developed bloody diarrhea of 3 days duration. The test results for the cattle revealed E. coli O26 in one cow, and E. coli O26 and O55 in another. E. coli O26, which was isolated in both cows and the grandmother of the index, were indistinguishably the same. Conclusions : We found that the E. coli O26 in the grandmother had originated from the cows, and that the E. coli O171 found in the index patient had been transmitted to the cousin through person-to-person contact.

• Journal of Nutrition and Health
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• 제24권4호
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• pp.308-313
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• 1991

초음파기(A-mode type, TATT, TH-500, Datoherutsu Co, Japan)를 이용하여 20-39세의 한국 사람들의 삼두박근, 견갑골하부, 장골위, 대퇴부의 피하지방을 측정하고, 이 피하지방 두께와 표준체중, 상대체중(relative body weight, RBW), body mass index(BMI), $R\ddot{o}hrer$지수와의 상관관계를 알아 보았다. 남성에서는 장골위의 피하지방 두께가 $9.04{\sim}9.51mm$로 가장 크고, 견갑골 아래가 $9.04{\sim}9.51mm$, 대퇴부가 $6.48{\sim}7.04mm$, 삼두박근이 3.48${\sim}$3.69mm이었다. 피하지방 두께와 여러 신체 지수와의 상관관계를 보면 삼두박근의 피하지방 두께와 BMI(r=0.618), $R\ddot{o}hrer$지수(r= 0.622)가, 장골위의 피하지방 두께와 체중(r=0.551). RBW(r=0.457), BMI(.= 0.478), $R\ddot{o}hrer$ 지수(r=0.418), 견갑골 하부의 피하지방 두께(r=0.433)가 양의 상관관계가 있었다. 여성에서는 대퇴부의 피하지방 두께가 $11.85{\sim}12.15mm$로 가장 크고 장골위가 $8.79{\sim}9.87mm$9.87mm, 견갑골하부 $6.21{\sim}6.91mm$, 삼두박근이 $4.80{\sim}4.93mm$이며, 대퇴부의 피하지방 두께가 RBW(r=0.339), BMI(r=0.347), $R\ddot{o}hrer$ 지수(r=0.330)와 양의 상관관계를 나타냈다. 남성의 경우 삼두박근의 피하지방 두께가 RBW, BMI, $R\ddot{o}hrer$지수와 상관관계가 있었고, 장골위의 피하지방 두께는 RBW, BMI, $R\ddot{o}hrer$ 지수외에 체중과도 상관관계가 있었으므로 초음파를 이용한 피하지방측정은, 남성은 장골위가 가장 유용함을 알 수 있었고, 여성의 경우는 대퇴부의 피하지방 두께가 RBW, BMI, $R\ddot{o}hrer$ 지수와 상관관계가 있었으므로 대퇴부의 피하지방 측정이 가장 유용함을 알 수 있었다. 비만 측정에서 초음파 장치는 여러 가지 장점이 있으므로 앞으로 이에 대한 연구가 있어야겠다.

• 한국광학회지
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• 제19권6호
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• pp.435-438
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• 2008

중수($D_2O$, 산화중수소)는 수소원자(H)보다 중성자 한 개가 더 많은 수소원자 동위원소(D)로 이루어진 물이다. 중수는 자연 상태의 물 가운데 5만분의 1정도 존재하며 경수($H_2O$)와 매우 비슷한 성질을 가지고 있으나 경수보다 11%정도 무겁고, 특이점은 235 K로 228 K인 경수와 약간의 차이를 가진다. 중수는 중성자를 흡수하여 원자로의 중성자 감속재로 쓰이고 최근 중수 농도에 따라 세포에 미치는 독성효과가 다르게 나타나는 현상이 발견 되어 암 치료에 사용하려는 연구가 진행되고 있다. 우리는 테라헤르츠 시간축 분광학을 이용하여 경수와 중수 혼합물의 농도별 굴절률과 흡수율 변화를 거대 분자간 결합에너지 영역을 포함하는 테라헤르츠 영역 ($0{\sim}2.5\;THz$)에서 측정하여 중수의 비율이 높을수록 굴절률은 감소하고 흡수율 또한 감소하는 결과를 얻었다.

• 한국세라믹학회지
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• 제42권3호
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• pp.178-181
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• 2005

Silicon oxynitride (SiON) 막은 플라즈마 화학기상증착법(PECVD)으로 $SiH_4,\;N_2O$와 $N_2$ 가스를 사용하여 $SiO_2/Si$ 위해 증착되었다. 증착 변수에 따라서 SiON 막의 굴절률은 prism coupler를 사용하여 1552nm 파장에서 $1.4480\~1.4958$까지 변화하였다. 평판 광도파로 코어로 사용되는 SiON 막의 두께는 $6{\mu}m$이고, buffer 막과의 굴절률 차이(An)는 $0.36\%$이다. 또한 식각 공정으로 $SiO_2$ 막 위에 증착된 SiON 막은 건식식각을 통해서 수행되었다. 광화이버에 $1.55{\mu}m$ 파장의 레이저론 입력단에 조사하였다. 결과적으로 저굴절률 차이 SiON 광도파로를 제작하였으며, 출력단에서 single-mode 형상을 확인하였다.

• Korean Chemical Engineering Research
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• 제53권6호
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• pp.776-782
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• 2015

$TiO_2$ 나노입자의 광촉매 반응을 억제하기 위해 평균 직경 3~5 nm의 $TiO_2-SnO_2$ 나노입자가 titanium tetraisopropoxide(TTIP)와 tin chloride의 가수분해 반응에 의해 합성되었다. 생성된 $TiO_2-SnO_2$ 나노입자를 졸-겔법에 의해 3-glycidoxypropyl trimethoxysilane(GPTMS)과 반응시킴에 의해 유-무기 혼성 코팅 용액이 제조되었다. 그 후 코팅 용액을 기재인 polycarbonate(PC) 시트 위에 스핀 코팅시키고, $120^{\circ}C$에서 열경화 시켜 고굴절률 하드코팅 도막이 제조되었다. $TiO_2-SnO_2$ 나노입자로부터의 코팅 도막은 $TiO_2$ 나노입자로부터 얻어진 코팅 도막의 2H에 비해 증가된 3H의 연필경도를 보였다. 또한 $TiO_2-SnO_2$ 나노입자로부터의 코팅 도막의 굴절률은 Sn/Ti 몰 비가 0에서 0.5로 증가함에 따라 633 nm 파장에서 1.543으로부터 1.623으로 향상되었다.

• 한국재료학회지
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• 제32권9호
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• pp.379-383
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• 2022

In this study, Barium Germanium glasses were prepared with a composition of xBaO-(72-x)GeO₂-8La₂O₃-20ZnO where x = 16.0, 18.0, 20.0, 22.0 and 24.0 mol% respectively. Their physical and optical properties, such as refractiveness index, glass transition temperature (T_g), softening temperature (T_s), transmittance and Knoop hardness were studied. The results showed that refractive index, T_g, T_s and coefficient of thermal expansion (CTE) increased with increasing BaO concentration. The refractive index of all the prepared samples was observed between 1.7811 to 1.7881. The Abbe number was calculated by formula using n_d (589.3 nm), n_f (656.3 nm) and n_c (486.1 nm) and observed to be between 38 to 40. The Abbe number of the prepared sample was similar to that of BaO and GeO₂. The transmittance of the prepared glasses was observed to be between 80 ~ 82 % throughout the range from 200 nm to 800 nm. Knoop hardness divided into seven steps were measured 5 class (≥ 450 ~ < 550) of all prepared samples.

• 한국재료학회지
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• 제32권12호
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• pp.560-564
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• 2022

In this study, lanthanum boron silicate glasses were prepared with a composition of x Li₂O-(60-x)B₂O₃-5CaO-5BaO-7ZnO-10SiO₂-10La₂O₃-3Y₂O₃ where x = 1,3,5,7, and 9 mol%. Each composition was melted in a platinum crucible under atmospheric conditions at 1,400 ℃ for 2 h. Clear glasses with a transmittance exceeding 85 % were fabricated. Their optical, thermal, and physical properties, such as refractive index, Abbe number, density, glass transition (T_g) and Knoop hardness were studied. The results demonstrated that refractive index was between 1.6859 and 1.6953 at 589.3 nm. The Abbe number was calculated using an equation for 589.3 nm (nd), 656.3 nm (nf) and 486.1 nm (nc) and was observed to be in the range from 57.5 to 62.6. As the Li₂O content increased, the glass transition temperature of the optical glass decreased from 608 ℃ to 564 ℃. If glass mold pressing is performed using a material with a low transition temperature and high mechanical strength, then the optical glasses developed in this study can be completely commercialized.

• 한국전기전자재료학회논문지
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• 제21권4호
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• pp.376-380
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• 2008

The optical properties of multi layered thin films with $Sb_2O_3/Na_3AlF_6/Sb_2O_3/Cr$ were simulated by using EMP(Essential Macleod Program). EMP is a comprehensive software package to design and analyse the optical characteristics of multi-layered thin film. $Sb_2O_3$ and $Na_3AlF_6$ were selected as a high refractive index and low refractive index material respectively. Additionally Cr was chosen as mid reflective material. Optical properties including color effect were systematically studied in terms of different optical thickness of low refractive index material. The optical thickness of $Na_3AlF_6$ was changed as 0.25, 0.5, 0.75 and $1.0\lambda$. The film with 0.25, 0.5, 0.75 and $1.0\lambda$ of optical thickness showed mixed color range between purple and red range, yellowish green and bluish green, purple and mixed color range of green and purple respectively.

• 펄프종이기술
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• 제29권3호
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• pp.43-50
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• 1997

The purpose of this study was to decrease pollutants of effluents from KP bleaching. Multistage bleaching that combined with O, Eo, and C/D stage was conducted, after optimum bleaching conditions of O, Eo, and C/D stage were determined. Moreover the properties for bleached pulps and pollution level of bleaching effluent were measured by each standard method. Due to increase on the brightness and delignification of pulps by O, Eo, and C/D stage bleaching. It was possible that bleaching sequences were reduced from five stage to four stage. In addition to, OC/DEoD and OC/DEopD bleaching sequences had higher brightness than CEDED bleaching sequence. The pulps bleached by O and Eo stage had higher in tensile index than conventional bleaching sequences with the similar results in burst and tear index. While each bleaching sequences had little differences, bleaching sequences with Eo stage had higher in physical properties than with Eop stage. The pollution level measured by Chemical Oxygen Demand(COD), Biochemical Oxygen Demand(BOD) and Color of bleaching effluents were much lower in combined bleaching sequences of O, Eo and C/D stage than that of CEDED sequence. Particularly, a pollution index of bleaching effluents generated by C/DEoDEB and OC/DEopDED bleaching sequences were lower than that from the other bleaching sequences.

• Journal of Periodontal and Implant Science
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• 제27권3호
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• pp.561-573
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• 1997

The keratinized mucosa around the implant is an important key in health of soft tissue and hard tissue. The purpose of this study is showed that the keratinized mucosa is associated with the keratinized mucosa index, plaque index, gingival index, probing depth. which is investigated to observing the peri-implant mucosa of mandibular partial edentulous patuent using periodontal parameter by previously published paper. It was estimated 6 site with regard to 80 fixture for 28 person, and the average age is 46.8. Each estimation is the order of less trauma, that is, plaque index, keratinized mucosa index, gingival index and probing depth. In this study, statstically analyzed treatment is used for Spss V 7.0 for Windows(Spss Inc, USA). The Kruskal Walis Test is used to compare the amount of the keratinized mucosa is into the $0{\sim}3$ index, with plaque index, gingival index and probing depth. Mann-whitney Test is used to interpreate the relation of plaque index and probing depth, which is showed significant difference. The Result are as follows 1. The kertinized mucosa index 3 amounts to 47.7%, which is much higher than the other indices and the index order is followed 3, 1, 2 and O. 2. The plaque index 1 amounts to 61.7%, which is much higher than the other indices and the index order is followed 1, 2, 3 and O. The plaque index 0 is significant to each of index(P<0.05). The plaque index is decrease as the keratinized mucosa index is increased. 3. The probing depth for 2mm, 1mm, 3mm is 48.9%, 23.5%, 16.8% respectively, which is most occupied. The probing depth 2mm and 3mm for the keratinized mucosa index is significant(P<0.05). The probing index is decreased as the keratinized mucosa index is increased. 4. The gingival index 0 amounts to 58.0%, which is much higher than the other indices and the index order is followed 0, 1, 2 and 3.