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Phenol함유 폐수의 처리에서 분말 활성탄 첨가의 영향 (Effects of Fine Powder Active Carbon Addition on the Wastewater Treatment Containing Phenol)

  • 강선태;김정목
    • 한국환경보건학회지
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    • 제22권3호
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    • pp.98-102
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    • 1996
  • This study investigated performance of the phenol degradation and reaction characteristics according to variation of phenol volumetric loading rates and dilution rates in suspension and PACT reactors using Pseudomonas sp. B3. 1. Removal efficiencies of the PAC unit indicated about 100 % with phenol volumetric loading rates from 0.4 phenol $kg/ma^3\cdot d$ to 1.2 phenol $kg/m^3\cdot d$, however, which of the suspension reactor showed about 100% with from 0.2 phenol $kg/m^3\cdot d$ to 0.75 phenol $kg/ma^3\cdot day$. 2. The cell density slightly was decreased from 298.2 mg/l to 272 mg/l, when dilution rate for suspension was reactor increased from 0.4 to 1.41 1/d, and also the cell density suddenly was decreased to 145.5 mg/l and was washed out at the dilution rate higher than 1.60 1/d. But the cell density for the PAC unit was linearly decreased with dilution rate of from 0.8 to 3.0 1/d, and showed 220.75 mg/l at maximum dilution rate. 3. The phenol utilization rate was increased from 0.008 to 0.031 phenol g/l$\cdot$h, when dilution rate for suspension reactor was increased from 0.4 to 1.5 1/d, however, the rate for the PAC unit was linearly increased from 0.017 to 0.061 phenol g/l$\cdot$h as variation changes from 0.017 to 0.061 phenol g/l$\cdot$h dilution rate.

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An Optimal Block Replacement Policy Using Items with Different Reliability

  • Lie, Chang-Hoon;Bae, Moon-Sik;Chun, Young-Ho
    • 한국국방경영분석학회지
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    • 제10권2호
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    • pp.61-73
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    • 1984
  • A block replacement policy using items with different reliability is discussed. We divide system unit failure modes into two modes and use less reliable unit when operating unit fails near the planned preventive replacement time. In this policy, item A has two failure modes. Mode-1 failure is removed by minimal repair, mode-2 failure by replacement. If mode-2 failure of item A happens in (0, $T-{\delta}$), failure item A is replaced by new item A. If mode-2 failure of item A happens in ($T-{\delta}$, T), failure item A is replaced by new item B. Item B should be cheaper and less durable than item A. Under this policy, we determine the preventive replacement interval $T^{*}$ and the interval ${\delta}^{*}$ of item B replacement which minimize the cost rate per unit time.

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외기인접방식에 따른 아파트 단위평면 특징에 관한 연구(I) (A Study on the Characteristics of the Apartment unit Plans According to the Outdoor Adjacency Methods (I))

  • 박몽섭
    • 한국주거학회논문집
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    • 제16권2호
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    • pp.19-25
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    • 2005
  • This paper call attention to the characteristics of apartment unit plans as to the outdoor adjacency methods. My arguments will attempt to investigate spatial composition and each room sizes of the unit plans. So far, very little has been done in this direction. I will limits myself to study 573 plans which have been designed from 1996 till 2003. What emerges from this analysis is that these samples divided 3 types derived from the outdoor adjacency methods. Type 1 limits itself to 39 square meters unit plans. Type 2 was distributed from 49 square meters to 200 square meters with the exception of 100-110 square meters. And, type 3 ranges from 59 to 160 square meters. Therefore, it could be profitable each room's environmental condition (daylight, ventilation and etc) and diverse apartment building types to design in extent 49-160 square meters.

배열형 소형 프레넬 렌즈가 결합된 LCD 백라이트의 설계 (Design of LCD Backlight Unit Coupled with Micro Fresnel Lens Array)

  • 정만호
    • 조명전기설비학회논문지
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    • 제20권2호
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    • pp.1-7
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    • 2006
  • LCD 백라이트의 효율을 향상시키기 위하여 배열형 소형 프레넬 렌즈(micro Fresnel lens array)가 결합된 도광판을 설계하였다. 배열형 소형 프레넬 렌즈(MFLA)는 blazed 형태 및 다단계 이진 형태를 채택하였다. MFLA는 기존 LCD 백라이트 장치에서 필요로 했던 프리즘판 및 확산판을 대체할 수 있다. MFLS가 적용된 도광판의 성능을 나타내기 위하여 휘도와 균일도 값 등을 계산하였다.

Electric-optical Characteristics of Backlight Unit with LED Light Source in Low Temperature Condition

  • Han, Jeong-Min;Seo, Dae-Shik
    • Transactions on Electrical and Electronic Materials
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    • 제8권2호
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    • pp.93-96
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    • 2007
  • LCD (liquid crystal display) industry is needed to goods of high reliability and is interested in products without harmful material. In this experiment, we made the LED backlight unit for Automotive-navigation. And for making this backlight unit we used to eight side emitting type white LEDs with 1 W high power of the lumileds company. We could know that this backlight unit releases to 6500 nit in 14 W power consumption and start up voltage time is under the 15ms in the ambient temperature $-20\;^{\circ}C$.

Disseminated life-threatening viral skin rash in a child with atopic dermatitis

  • Astrid Herzum;Corrado Occella;Ehab Garibeh;Lodovica Gariazzo;Gianmaria Viglizzo
    • Clinical and Experimental Vaccine Research
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    • 제12권2호
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    • pp.176-178
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    • 2023
  • We report the case of a toddler, with a history of mild atopic dermatitis (AD) since early infancy, presented to the Giannina Gaslini, a pediatric polyclinic hospital, 14 days after measles-mumps-rubella (MMR) vaccination, for the occurrence of a disseminated vesico-pustular rash, accompanied by general malaise, fever, restlessness, and anorexia. Eczema herpeticum (EH) was diagnosed clinically and confirmed by laboratory examinations. The exact pathogenesis of EH in AD is still debated and possibly involves an inter-play between altered cell-mediated and humoral immunity, failure to up-regulate antiviral proteins, and exposure of viral binding sites through the dermatitis and an epidermal barrier failure. We hypothesize that in this particular case, MMR vaccination might have played an additional important role in the alteration of innate immune response, facilitating the manifestation of herpes simplex virus type 1 in the form of EH.

미숙아의 시술 관련 통증 반응 (Pain Response to Procedural Pain in Premature Infants)

  • 김정숙;이은정;함은하;김지현;이영희
    • Child Health Nursing Research
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    • 제16권4호
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    • pp.352-359
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    • 2010
  • Purpose: To explore premature infants' pain response to routine procedures in the neonatal intensive care unit (NICU). Methods: The participants were 56 preterm infants who showed 149 pain responses to 8 high frequency routine procedures which were evaluated using the Premature Infant Pain Scale (PIPS). Videotaped recording was used for data collection. Data were analyzed with descriptive analysis, paired t-test, and Pearson's correlation coefficient. Results: PIPS scores for each procedure were as follows; for removal of central catheter dressing, 6.17 (2.04), venous sampling, 6.12 (2.87), intramuscular injection, 6.05 (2.38), insertion of a peripheral line, 5.38 (2.16), insertion of feeding tube, 4.40 (1.34), heel stick, 4.33 (1.23), insertion of central line, 4.00 (2.12), and endotracheal suctioning, 2.90 (1.25). PIPS score was negatively correlated with gestational age (r=-.218, p=.007) and birth weight (r=-.249, p=.002) among general characteristics of the infants. Conclusion: The majority of 8 routine procedures were found to be painful for premature infants in the NICU. Therefore, adequate pain management related to procedures should be provided to premature infant in the NICU.

고해상도 기후시나리오를 이용한 논용수 수요량 및 단위용수량의 기후변화 영향 분석 (The Impacts of Climate Change on Paddy Water Demand and Unit Duty of Water using High-Resolution Climate Scenarios)

  • 유승환;최진용;이상현;오윤경;박나영
    • 한국농공학회논문집
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    • 제54권2호
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    • pp.15-26
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    • 2012
  • For stable and sustainable crop production, understanding the effects of climate changes on agricultural water resources is necessary to minimize the negative effects which might occur due to shifting weather conditions. Although various studies have been carried out in Korea concerning changes in evapotranspiration and irrigation water requirement, the findings are still difficult to utilize fordesigning the demand and unit duty of water, which are the design criteria of irrigation systems. In this study, the impact analysis of climate changes on the paddy water demand and unit duty of water was analyzed based on the high resolution climate change scenarios (specifically under the A1B scenario) provided by the Korea Meteorological Administration. The result of the study indicated that average changes in the paddy water demand in eight irrigation districts were estimated as -2.4 % (2025s), -0.2 % (2055s), and 3.2 % (2085s). The unit duty of water was estimated to increase on an average within 2 % during paddy transplanting season and within 5 % during growing season after transplanting. This result could be utilized for irrigation system design, agricultural water resource development, and rice paddy cultivation policy-making in South Korea.

매트릭스 두께가 MCFC 장기 성능에 미치는 영향 (The effect of the matrix thickness on the long term performance of MCFC)

  • 김윤영;한종희;윤성필;남석우;임태훈
    • 한국수소및신에너지학회논문집
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    • 제16권2호
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    • pp.170-179
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    • 2005
  • Electrolyte loss is considered as one of the major obstacles limiting the life time of molten carbonate fuel cells (MCFCs). Unit cells with an effective area of 100 $cm^2$ were prepared and were operated to determine the optimum matrix thickness which contains the maximum amount of electrolyte without serious preformance loss caused by high resistance. Matrices with different thickness, 1.45, 1.8, and 2.3 mm, were used in unit cells and those cells were operared about 5000, 10000, and 4000 hrs. The unit cell used 1.8 mm thick matrix showed 0.85 V (at 150 mA/$cm^2$) as the intial performance and this cell voltage is not lower than the cell voltage obtained in the cell with 1 mm thick matrix. This cell was operated for 10000 hrs. The cell used 1.45 mm thick matrices showed 16.6 % in the electrolyte loss after 5000 hr operation. In the case of the cell with 2.3 mm thick matrix, the initial cell voltage was below 0.80 V (at 150 mA/$cm^2$). For thermal cycle test, the gas crossover amount of unit cell used 1.8 mm thick matrix was much less than that of the cell with 1.0 mm thick matrix.

광중합 복합레진의 색안정성 및 투명도 변화에 관한 가속시험 (AN ACCELERATED TEST FOR COLOR STABILITY AND OPACITY CHANGE OF LIGHT CURING COMPOSITE RESINS)

  • 황인남;오원만
    • Restorative Dentistry and Endodontics
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    • 제18권1호
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    • pp.215-226
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    • 1993
  • Color stability of tooth colored restorative resins is an important factor, particularly in anterior teeth restoration. The purpose of this study was to evaluate the color stability and opacity change of several light curing composite resins. Specimens of eight composite resins(Prisma AP. H., Brilliant Enamel, Charisma, Durafil, Helio Progress, Herculite XR, P-50 and Silux Plus) were divided into two groups : In Group 1, the specimens were polymerized by visible light curing unit for 60 seconds on both sides and in Group 2, the post-cured specimens were heat tempered by light/heat curing unit for 45 units(about 18 min.). All specimens were stored in distilled water at $60^{\circ}C$ for 30 days. The color characteristics($L^*,a^*,b^*$) and opacity of the specimens before and after immersion were measured by spectrocolorimetry and the total color difference(${\Delta}E^*$) and opacity change (${\Delta}Y%$) were computed. The results obtained were as follows : 1. SP and APH in both groups, DF, HP and HXR in Group 1 showed ${\Delta}E^*$-value above 2.0. 2. DF, HP, SP and HXR in Group 1 showed higher ${\Delta}E^*$-value than in Group 2, but the others had no significant difference. 3. The opacity of CH and HXR in Group 1, and of CH and BE in Group 2 decreased after immersion, while that of the others increased. 4. Opacity change of BE, P50 and HXR was significantly different between Group 1 and 2. These results suggest that color change in the post-cure heat tempered specimens by light/heat curing unit was smaller than that of the specimens polymerized by visible light curing unit. No clinically detectable opacity changes were noted for any materials in either goup.

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