• KIEAE Journal
• /
• 제6권2호
• /
• pp.19-26
• /
• 2006

Recently, building requirements have been saturated and residents are demanding a variety of building exterior materials faced with roofs, walls, windows and doors. On the other hand, when building exterior materials are exposed with ultra violet rays during some periods, these will be influenced deterioration effects like discolorations, exfoliations and cracks and will be needed exchange of materials. In this study, main 17-provinces of Korea were collated climate data and counted the computation results with an assumption formula for calculating ultra violet rays amounts. Lastly, ultra violet rays map of Korea was made by the counted data and was considered tendencies. Accordingly, in the phase of design the designer can select the appropriate exterior materials which have durabilities and resistances of ultra violet rays. So hereafter this study can be a foundation study to sustain building exterior materials with ultra violet rays damages. Below is the summary of Korean ultra violet rays tendency. 1. Ultra violet rays during 1 year is from about $180MJ/m^2$ to about $210MJ/m^2$. 2. Southern province ultra violet rays is higher than northern province. 3. Annually counted rays is higher and higher.

• 한국동물위생학회지
• /
• 제22권4호
• /
• pp.357-361
• /
• 1999

The most harmful nitrogenous compounds in fish-breeding place using are ammonia and nitrate. Excessively high total nitrogen concentration is the signal of unbalance for breeding fishes in seawater and may result overfeeding or overstocking without seawater treatment system. The failure of elimination for the organic ingredients or nitrogen compounds can also cause the consequence of inadequate oxygen concentration in seawater, either. The study shows the effect of biofilter and W disinfector of seawater in the fish- breeding place. In the results, these tools had ammonia, nitrite, nitrate and decreased 71.8%, 27.6% and 1%, respectively, and the total number of microorganisms decreased up to 81.9%.

• 한국염색가공학회지
• /
• 제25권3호
• /
• pp.165-171
• /
• 2013

A new monoazo violet dye optimized for polyolefin fibers such as polypropylene and ultra high molecular weight polyethylene fibers was synthesized and its dyeability was investigated. Two hexyl groups were introduced to coupler, 2,5-dimethoxyaniline, in order to increase hydrophobicity of the dye. The maximum absorption wavelength was appeared at 580nm, which meant that the dye showed violet color. From the dyeing results at various conditions, the optimum dyeing was determined as $130^{\circ}C$ for 1 hour with 5% owf of dyes. The good fastness ratings to washing, rubbing were obtained showing at least 4 for both fibers. Light fastness was acceptable for polypropylene fibers giving ratings 3~4. However, relatively poor light fastness was obtained in case of ultra high molecular weight polyethylene fibers showing ratings 2.

• 미생물학회지
• /
• 제10권1호
• /
• pp.29-34
• /
• 1972

The present study is of ultra-fine structure of Cryptococcus neoformans by means of electron microscopy and reveals the following : 1) In constrast to the bacteria, the normal Cryptococcus neofrmans contains nuclear enveloped with nuclear menbrane, mitochondria, endoplasmic reticulum, distinct cell wall and cell membrane, vacuoles and storage granules as observed in the eucaryotic cells. 2) In apparent cell walls and cell membrane with the appearance of electron transparent area (ETA) and changes of cell morphology were observed in the ultra-violet ray irradiated cell. 2) In apparent cell walls and cell membrance with the appreance of electron transparent area (ETA) and changes of cell morphology were observed in the ultra-violet ray irradiated cell. 3) Morphology changes and cytoplasmic element abnormality was increased with irradiated time. 4) Increase of electron transparent area was thought to be associated with degradation of cell.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
• /
• pp.182-183
• /
• 2007

Recently, diverse techniques for diagnosis on power equipments of the live wire conditions are developed. These techniques are very important that find out the fault signs in power equipments. This paper is Compared with Ultra-Violet and Ultra-Sonic Generated by an Insulator at 22.9kV. The volume of UV images are increased by the square of the applied voltage. The output signals of ultrasonic are detected at about 20kV to 30kV. Hereafter, through the continuous DAQ and analysis, these techniques are the effective method for the improvement of the exciting diagnosis.

• 상하수도학회지
• /
• 제37권5호
• /
• pp.253-259
• /
• 2023

Bioreactors are devices used by sewage treatment plants to process sewage and which produce active sludge, and sediments separated by solid-liquid are treated in anaerobic digestion tanks. In anaerobic digestion tanks, the volume of active sludge deposits is reduced and biogas is produced. After dehydrating the digestive sludge generated after anaerobic digestion, anaerobic digested wastewater, which features a high concentration of organic matters, is generated. In this study, the decomposition of organic carbon and nitrogen was studied by advanced oxidation process. Ozone-microbubble flotation process was used for oxidation pretreatment. During ozonation, the TOC decreased by 11.6%. After ozone treatment, the TOC decreased and the removal rate reached 80.4% as a result of the Ultra Violet-Advanced Oxidation Process (UV-AOP). The results with regard to organic substances before and after treatment differed depending on the organic carbon index, such as CODMn, CODCr, and TOC. Those indexes did not change significantly in ozone treatment, but decreased significantly after the UV-AOP process as the linkage treatment, and were removed by up to 39.1%, 15.2%, and 80.4%, respectively. It was confirmed that biodegradability was improved according to the ratio of CODMn to TOC. As for the nitrogen component, the ammonia nitrogen component showed a level of 3.2×10² mg/L or more, and the content was maintained at 80% even after treatment. Since most of the contaminants are removed from the treated water and its transparency is high, this water can be utilized as a resource that contains high concentrations of nitrogen.

• 대한지구과학교육학회지
• /
• 제8권1호
• /
• pp.35-44
• /
• 2015

The purpose of this paper is to identify the conceptions of middle school and high school students about visible light, Ultra violet(UV) and Infrared ray(IR). We administered questionnaire 40 people of middle school 3rd students and 43 people of high school 2nd students in Gyeonggi-do. Misconceptions about visible light, UV and Ir were observed in many students. The results of study are as follows: Firstly, Many students think that it is possible to see objects without visible light. The explanations given by students for the visiblity of objects in darkness indicates a heavy reliance on personal experiences. Secondly, we have confirmed that high school students well understand the fact that the object reflects the light. However, a significant number of students exhibited an eye-centered perspective of vision. Thirdly, students had a variety of ideas about the meaning of the term UV and IR. Analysis of questionnaire data indicates that many students believe that it is possible to see objects in the presence of UV light alone.

• Journal of Astronomy and Space Sciences
• /
• 제39권3호
• /
• pp.87-98
• /
• 2022

The Far-UltraViolet (FUV) imager onboard the Ionospheric Connection Explorer (ICON) spacecraft provides two-dimensional limb images of oxygen airglow in the nightside low-latitude ionosphere that are used to determine the oxygen ion density. As yet, no FUV limb imager has been used for climatological analyses of Equatorial Plasma Bubbles (EPBs). To examine the potential of ICON/FUV for this purpose, we statistically investigate small-scale (~180 km) fluctuations of oxygen ion density in its limb images. The seasonal-longitudinal variations of the fluctuation level reasonably conform to the EPB statistics in existing literature. To further validate the ICON/FUV data quality, we also inspect climatology of the ambient (unfiltered) nightside oxygen ion density. The ambient density exhibits (1) the well-known zonal wavenumber-4 signatures in the Equatorial Ionization Anomaly (EIA) and (2) off-equatorial enhancement above the Caribbean, both of which agree with previous studies. Merits of ICON/FUV observations over other conventional data sets are discussed in this paper. Furthermore, we suggest possible directions of future work, e.g., synergy between ICON/FUV and the Global-scale Observations of the Limb and Disk (GOLD) mission.

• 한국산학기술학회논문지
• /
• 제17권12호
• /
• pp.482-487
• /
• 2016

파장 400 nm 이하의 자외선은 눈 건강에 매우 해롭다. 특히 UVA (315 nm ~ 400 nm)는 백내장, 설안염, 초자체경화 등을 유발할 수 있고, UVB (280 nm ~ 315 nm)는 결막염, 각막염 및 설안염 등을 일으킬 수 있다. 따라서 폴리머 안경렌즈를 사용함에 있어서 자외선의 차단 기능과 가시광선 영역에서 투과되는 빛을 증가시키고, 안경렌즈 표면에서 형성되는 허상을 방지하는 반사방지 기능은 매우 중요하다. 본 연구에서는 m-자일릴렌 디이소시아네이트 모노머와 2,3-Bis-1-propanethiol 모노머 및 벤조트리아졸 UV 흡수제 (SEESORB 709), 안료 혼합물, 이염화 이부틸 주석 촉매제, 알킬인산 에스터 이형제 등의 혼합물을 인젝션 몰드 방법으로 열중합 공정을 적용하여, 굴절률 1.67의 고굴절률 폴리머 안경렌즈를 제조하였다. 폴리머 안경렌즈 표면에서의 반사를 줄이기 위하여 렌즈 양면에 다층박막 반사방지 코팅을 E-beam 증착 시스템으로 코팅하였다. 자외선 차단 폴리머 안경렌즈의 광학적 특성을 UV-visible spectrometer로 분석하였고, 반사방지층을 구성하는 박막의 굴절률, 표면거칠기 등과 같은 박막소재 특성을 각각 Ellipsometry 및 원자힘 현미경으로 분석하였다. 분석 결과 제조된 안경렌즈는 395 nm 파장 이하의 자외선을 99% 이상 완벽하게 차단하였다.

• 한국식품과학회지
• /
• 제4권4호
• /
• pp.259-264
• /
• 1972

국산(國産) 라면제품을 형광등조사구(螢光燈照射區) 고온암소구(高溫暗所區) 자외선조사구(紫外線照射區) 등의 처리구(處理區)로 나누어 20주(週)동안 저장하고, 경시적(經時的)으로 산가(酸價) 과산화물가(過酸化物價) carbonyl가(價) TBA가(價) 지방산조성(脂肪酸組成) 옥도가(沃度價) 등의 지방산화현상(脂肪酸化現象)을 살펴 본 바 다음과 같은 결과를 얻었다. 전반적으로 형광등조사구(螢光燈照射區) 및 고온암소구(高溫暗所區)의 라면은 완만한 산화현상(酸化現象)을 보였으며, 저장 16주(週)에 변패취(變敗臭)를 확인하였고, 자외선조사구(紫外線照射區)의 라면은 저장초(初)부터 급격한 산화(酸化)가 일어났으며, 저장 4주(週)에 변패취(變敗臭)를 확인하였다. 2) 산가(酸價) 과산화물가(過酸化物價) TBA가(價)등은 각처리구(名處理區) 공(共)히 전실험기간동안 증가하였으며 자외선조사구(紫外線照射區)에서 그 증가현상(增加現象)은 현저하였다. 특히 TBA가(價)는 자외선조사구(紫外線照射區)에서 저장 4주(週)이후 급격히 증가하여 10주(週)에 그 정점(頂點)을 이루고 다시 감소하였다. 이 때의 bound malonaldehyde는 14주(週)까지 증가하다가 그 이후 완만히 변화하였다. 3) 저장초(貯藏初) 그리고 저장(貯藏) 12주(週)의 고온암소구(高溫暗所區) 및 자외선조사구(紫外線照射區)의 라면유지(油脂)에 대한 지방산조성(脂肪酸組成)을 살펴 본 결과 고온암소구(高溫暗所區)에선 큰 변화가 없었으며, 자외선조사구(紫外線照射區)에선 저장초(貯藏初)의 지방산조성(脂肪酸組成)에 비(比)하여 linoleic acid 등 불포화 지방산의 상대적(相對的)인 감소현상을 볼 수 있었으며 저장 중 옥도가(沃度價)의 감소(減少)가 이러한 사실(事實)을 뒷받침하고 있다.