해운대 달맞이 언덕에 있어서 바다조망경관의 역사적 변천에 관한 연구

강영조,신수안,조미나,이현주,박은희 동아대학교 건설기술연구소 2000 硏究報告 Vol.24 No.1

The purpose of this study is to clarify the historic transition of the prospects on Haeundae dalmaji hill. Dalmaji hill is well known for a character of configuration on the ground with the scene of the sea. We will infer that how did it change the prospects of Dalmaji hill's sea through the analyzing of the preset situation and location of building on the hill. (1) We investigated the stories of the building, the history, the business condition. (2) We collect the twenty four view points which is able to have seascape on the hill, being easily approaching to the road, and condition of changing the building. (3) We clarified the transition of seascape prospect and considered the characteristics of the six types from which were divided the condition of seascape prospect.

광중합형 수복용 복합레진의 인장강도에 미치는 thermal cycling과 시효 처리의 영향

백상현,채민수,이주형,김태조,배태성 대한치과기재학회 1998 대한치과재료학회지 Vol.25 No.1

The improvement in the mechanical properties of restorative composites has contributed to their increased use in recent years. In spite of their growing popularity, composites still have low resistance to fracture and wear in oral environments. This study was performed to examine whether the tensile strengths of light-cured restorative composites were affected by thermal cycling and aging in water. Five commerically available light-activated composites(Heliomolar : HM, Aelitefil : AF, Amelogen : AG, Clearfil AP-X : CF, Z100 : ZH) were used. Rectangular tension test specimens were fabricated in a teflon mold giving 5 mm in gauge length and 2mm in thickness. All samples were divided into 3 groups. Group 1 was stored in a desiccator for 10 days. Group 2 was immersed in a 37℃ distilled water for 10 days. Group 3 was subjected to 10,000 thermal cycles between 5℃ and 55℃, and the immersion time in each bath was 15 seconds per cycle. Tensile testing was carried out at a crosshead speed of 0.5 mm/min and fracture surfaces were observed with scanning electron microscope. The results obtained were summarized as follows; 1. The strength data fit to single-mode Weibull distribution(r²> 0.86) and Weibull parameters decreased after thermal cycling test. 2. The highest characteristics strength was observed in the CF group but the highest Weibull modulus was obtained in the AF group after thermal cycling test. 3. The highest tensile strength value of 83.92 MPa was obtained in the CF group and the lowest value of 13.91 MPa was obtained in the AG group. Tensile strengths showed no significant difference between HM and AG groups but other groups showed the significant differences in each group(p<0.05). 4. According to the microscopic observation of the fracture surfaces, fractures of large fillers were observed in the hybrid composites of the AF and CF groups.

오매(Fructus Mume)의 항산화물질의 분리 및 특성연구

황현주,안은미,백남인,조재선,김해영 경희대학교 생명자원과학연구원 1998 硏究論文集 Vol.19 No.-

천연물로부터 새로운 항산화제를 개발하기 위한 연구의 일환으로 한방에서 사용되는 한약재 중의 하나인 오매(烏梅)의 물 추출물과 메탄을 추출물 및 순차 분획물에 대해 팜유, 우지와 돈지를 기질로하여 유지저아시험, Rancumat method, 전자공여작용 등으로 항산화성을 확인한 결과, EtOAc 분획물에서 강한 항산화 활성을 나타내어 column chromatography, thin layer chromatography를 통하여 활성성분에 관한 연구를 시도하였다. 1. 오매 용매분획물 중 EtOAc 분획물(400 ppm)은 유지저장실험(60℃)에서, 팜유, 우지와 돈지에 모두 우수한 효과를 나타내었으며, 특히 우지에서 높은 활성을 나타내었고, BHA(200 ppm)와 α-tocopherol(200 ppm)보다 활성이 높았다. 2. 오매 EtOAc 분획물(400 ppm)은 Rancimat method에서는 팜유, 우지와 돈지에 비교적 우수한 효과를 나타내었으며, 우지에서 AI가 4.39로 상당히 높은 활성을 나타내었다. 3. 오매의 용매분획물 중 EtOAc 분획물이 DPPH라디칼에 대한 강한 소거활성을 나타내었으며, 그 활성은 EtOAc 분획물의 농도에 의존하여 증가하였고, SC_(50)은 21.2μg/ml이었다. 4. 오매 EtOAc 분획물에서 분리한 8개 획분 중 E4에서 SC_(50)이 16.7μg/ml으로 높은 DPPH 라디칼 소거활성을 나타내었으며, 원인 물질은 여러 가지 스펙트럼 측정 결과 수종 물질이 혼합물인 것으로 밝혀져, 보다 순수한 형태로의 분리 후 정확한 동정의 시도가 요구되었다. Fructus Mume is the roasted hits of Prunus mwme and has been used as tradibonal Chmese medicine. The anboxidatwe effect of the extract from Fructus Mume was measured using different methodsn such as, electron donating abdihes(EDA), Rancimat and oven tests. The methanol extract obtained from the Fructus Mume was solvent-fractionated with ethyl acetate, n-butanol and water, respectively. The ethyl acetate fraction showed the highest antioxidative activity among them. To identify the compounds with antioxidative activity, the isolates from thm layer chromatography were studied further. This study demonstrates that Fructus Mume might be useful for the prevention or treatment of disorders associated with oxidative damage.

유당의 첨가가 성장기 암컷 흰쥐에서 골함량과 골밀도에 미치는 영향

최미자,조현주 啓明大學校 生活科學硏究所 2002 科學論集 Vol.- No.-

The effects of dietary lactose supplementation on bone mineral density and bone mineral content in growing rats are uncharacterized. We studied growing female rats fed a diet either control of supplemented with lactose for 9 weeks. The animal was scanned to determine the BMD and BMC using dual energy X-ray absorptiometry (FIXImus, GE Lunar Corporation, Madison, WI). Food intake and FER were not affected by loctose supplementation. But the lactose group had significantly higher spine bone mineral density(0.1517±0.0034(g/㎠) vs 0.1626±0.0095(g/㎠)) and spine bone mineral density/weight than the control group. And femur bone mineral density/weight as well as femur bone mineral content/weight were higher in the lactose supplemented group. These data suggest that lactose supplementation may be a useful way in growing children in which there is a desire to increase bone mineral density.

복귀돌연변이시험을 이용한 이온화에너지 처리 우유 및 아이스크림의 유전독성학적 평가

유지숙, 한선경, 신명수, 구본철, 최지현, 이주운, 조철훈, 함준상, 이완규 충북대학교 동물의학연구소 2008 Journal of Biomedical and Translational Research Vol.9 No.1

본문참고

집적화된 실리콘 압력센서의 출력전압 보상파라미터 추출 및 그 특성

이보나,김건년,박효덕,신상모,이경탁,김찬,권혁채,이상조,박현주 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

An integrated silicon pressure sensor has been designed, fabricated and tested. The signal conditioning circuits were designed to include calibration and temperature compensation of output voltage through trimming of diffusion and ion-implanted resistors. Before trimming of resistors, the compensation parameters such as pressure sensitivity, temperature coefficient of pressure sensitivity, temperature coefficient of piezoresistors and pressure sensitivity of piezoresistors were measured. Then offset voltage, span, and temperature coefficients of offset voltage and span were calibrated by trimming of resistors. The measured output voltage met our design specification and simulation value above room temperature. But, the measured output voltage at -30°C deviated from our design specification and simulation value because the offset voltages were found to vary randomly as a function of temperature.

High prevalence of Enterococcus spp. from dogs with otitis externa

( Hyun Jung Jo ),( Hee Sun Chae ),( Hyun Ju Kim ),( Min Ju Kim ),( Gyu Nam Park ),( Sang Hun Kim ),( Kyung Soo Chang ) 한국동물위생학회 2012 韓國家畜衛生學會誌 Vol.35 No.2

Otitis externa (OE) is a frequent disease in the ear canals of dogs. To identify the pathogens causing OE in dogs and to determine their antimicrobial resistances, specimens were collected from animal hospitals in Daejeon. The isolates were examined by morphological and biochemical tests, 16S rRNA analysis and antimicrobial susceptibility tests. We analyzed correlation between the isolated pathogens and external factors of dogs such as breed, age, gender, ear mite, hair in ears and experience with antibiotic therapy. Thirty three strains of bacteria were isolated from 26 of the 68 heads of dogs with OE. The most isolated bacteria were Enterococcus faecalis (E. faecalis) followed by Staphylococcus aureus (Sta. aureus), Sta. pseudointermedius, E. faecium, E. avium and Streptococcus canis (Strep. canis) in order of frequency of occurrence. Isolation frequency of Enterococcus spp. and Staphylococcus spp. were 51.5% and 45.5%, respectively. E. faecalis and E. faecium isolates showed VanB phenotype, which is resistant to vancomycin but sensitive to teicoplanin were 58% and 25%, respectively. Nine isolates among total twelve isolates of E. faecalis were isolated from the dogs treated with antibiotics. There was no methicillin-resistant Sta. aureus (MRSA), but were MR-Sta. pseudointermedius (MRSP) (57.1%) and vancomycin-resistant (VR)-Sta. pseudointermedius (14.3%) (VRSP) showing VanB phenotype. However, vanA, vanB and vanC genes were not detected in VR isolates from the dogs. Taken together, VR-Enterococcus spp. (VRE) is one of the major pathogens in domestic animals, as well as community- and hospital-acquired infection.

Time-Resolved Photocurrent of an Organic-Inorganic Hybrid Solar Cell Based on Sb2S3

Hyun-Jun Jo,Seung Hyun Kim,Jong Su Kim,Sang-Ju Lee,Dae-Hwan Kim 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.4

In this study, the optical and the electrical properties of a hybrid solar cell (SC) based on a zinc oxide (ZnO)/antimony trisulfide (Sb2S3)/poly(3-hexylthiophene) (P3HT) heterojunction were investigated. ZnO and Sb2S3 films were grown using atomic layer deposition (ALD). Photoluminescence (PL) spectra show band-to-band emission of the Sb2S3 layer at around 724 nm at room temperature. The room-temperature current decay behaviors were investigated based on the timeresolved photocurrent (TRPC). With increasing intensity (P) of the excitation pulse laser, the current decay time gradually decreased due to an enhancement of the carrier recombination. Optically biased TRPC was demonstrated with energies above and below the band gap of Sb2S3 to investigate the effect of the background carrier concentration during carrier transport. We found three carrier exhaustion processes during carrier transport due to the recombination behaviors at given carrier injection levels. At high injection level, the current decay times were also affected by the hole diffusion rate in the P3HT h-conducting layer.

Effects of isoflavone supplementation on the bone mineral density of growing female rats

Hyun-Ju Jo,Mi-Ja Choi 대한지역사회영양학회 2008 Nutrition Research and Practice Vol.2 No.2

This study was focused on whether or not isoflavones affect the increase in bone mineral density of growing females. Female Sprague-Dawley rats (60 ± 5 g) were randomly assigned to two groups and provided control diets (control group) or isoflavone-supplemented diet (IF group, 57.8 mg isoflavones/100 g diet) for 9 weeks in growing female rats. Measurements of Bone Mineral Density (BMD) and Bone Mineral Content (BMC) on the experimental animals were executed in the 3<SUP>rd</SUP>, 6<SUP>th</SUP>, 9<SUP>th</SUP> weeks. In result, there was no significant difference in spine BMD between the isoflavones supplemented group and the control group. But, the IF group tended to have higher BMD than the control group in between 3 and 9 experimental weeks, and the striking difference could be shown in the 6<SUP>th</SUP> week of feeding. In case of femur BMD, the effects of added isoflavones appeared in the 6<SUP>th</SUP> week of feeding, and it became intensified in the 9<SUP>th</SUP> week of feeding to the extent that the BMD in the IF group was significantly higher than that of the control group (p<0.05). In conclusion, isoflavone supplementation increased spine BMD per weight in the 6<SUP>th</SUP> week of feeding, and affected the increase of femur BMD in the 9<SUP>th</SUP> week. The result of the experiment implies that it affects positively the formation of spine and femur BMD of growing female rats. The study also suggests that the effects of isoflavone on the pattern of BMD formation might differ from the parts of bones.

Nocturnal fine particulate nitrate formation by N₂O₅ heterogeneous chemistry in Seoul Metropolitan Area, Korea

Jo, Hyun-Young,Lee, Hyo-Jung,Jo, Yu-Jin,Lee, Jong-Jae,Ban, Soojin,Lee, Jin-Ju,Chang, Lim-Seok,Heo, Gookyoung,Kim, Cheol-Hee Elsevier 2019 Atmospheric research Vol.225 No.-

<P><B>Abstract</B></P> <P>This study investigated the potential of fine nitrate (NO<SUB>3</SUB> <SUP>−</SUP> in PM<SUB>2.5</SUB>) formation in Seoul Metropolitan Area (SMA) by nighttime dinitrogen pentoxide (N<SUB>2</SUB>O<SUB>5</SUB>) heterogeneous chemistry during March 16–18, 2016, relatively dry and stagnant early spring days, by intervening N<SUB>2</SUB>O<SUB>5</SUB> uptake coefficients (reactive uptake probability, γN<SUB>2</SUB>O<SUB>5</SUB>) in modeling with WRF-CMAQ. Simulations of a base case and two sensitivity tests with default (Davis et al., 2008), zero and decupled (tenfold) γN<SUB>2</SUB>O<SUB>5</SUB> showed that impacts of γN<SUB>2</SUB>O<SUB>5</SUB> on NO<SUB>3</SUB> <SUP>−</SUP> and PM<SUB>2.5</SUB> are sensitive to relative humidity (RH) and sulfate-nitrate-ammonium (SNA) conditions. The base case simulation generally underestimated NO<SUB>3</SUB> <SUP>−</SUP> and PM<SUB>2.5</SUB> levels in comparison to observations. Even with decupled γN<SUB>2</SUB>O<SUB>5</SUB>, modeled NO<SUB>3</SUB> <SUP>−</SUP> and PM<SUB>2.5</SUB> concentrations showed relatively small increases under conditions that RH is relatively low in the range of 20 to 40% and SNA levels are severely underestimated (e.g., lower by one third) in the base case simulation. Comparisons of NO<SUB>3</SUB> <SUP>−</SUP> and PM<SUB>2.5</SUB> concentrations in SMA between simulations with differently specified γN<SUB>2</SUB>O<SUB>5</SUB> indicated that N<SUB>2</SUB>O<SUB>5</SUB> heterogeneous chemistry has potential to (1) form additional nitric acid (HNO<SUB>3</SUB>), (2) further react with ammonia (NH<SUB>3</SUB>) emitted from various sources including agricultural sources outside of SMA urban-core areas, and (3) contribute to NO<SUB>3</SUB> <SUP>−</SUP> and PM<SUB>2.5</SUB> formation in SMA. Additional modeling and observational studies on heterogeneous N<SUB>2</SUB>O<SUB>5</SUB> chemistry are needed to improve our understanding of NO<SUB>3</SUB> <SUP>−</SUP> and PM<SUB>2.5</SUB> formation and better forecast PM<SUB>2.5</SUB> pollution levels over SMA or other urban areas with abundant nitrogen oxides emissions and ammonia emissions such as agricultural emissions from surrounding areas.</P> <P><B>Highlights</B></P> <P> <UL> <LI> N<SUB>2</SUB>O<SUB>5</SUB> heterogeneous chemistry in the PM<SUB>2.5</SUB> formation was investigated by intervening the uptake coefficient (rN<SUB>2</SUB>O<SUB>5</SUB>). </LI> <LI> Simulations with the improved uptake coefficient (rN<SUB>2</SUB>O<SUB>5</SUB>) contributed to better PM<SUB>2.5</SUB> prediction in some conditons. </LI> <LI> Observational studies are needed to understand the nitare formation in the areas with abundant NO<SUB>x</SUB> and NH<SUB>3</SUB> emissions. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>