• 상하수도학회지
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• 제22권1호
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• pp.15-22
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• 2008

This study collected the latest 30-year (1976~2005) continuous rainfall data hourly recorded at 61 meterological observatories in Korea, and the continuous rainfall data was divided into individual rainfall events. In addition, distribution charts of average rainfall event-depth were created to facilitate the application to the overflow risk-based design of detention storage basin. This study shows that 4 hour is appropriate for SST (storm separation time) to separate individual rainfall events from the continuous rainfall data, and the one-parameter exponential distribution is suitable for the frequency distribution of rainfall event depths for the domestic rainfall data. The analysis of the domestic rainfall data using SST of 4 hour showed that the individual rainfall event was 1380 to 2031 times, the average rainfall event-depth was 19.1 to 32.4mm, and ranged between 0.877 and 0.926. Distribution charts of average rainfall event-depth were created for 4hour and 6 hour of SST, respectively. The inland Gyeongsangbuk-do, Western coastal area and inland of Jeollabuk-do had relatively lower average rainfall event-depth, whereas Southern coastal area, such as Namhae, Yeosu, and Jeju-do had relatively higher average rainfall event-depth.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6547-6552
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• 2014

Background: Cancer is a major life event that imposes huge economic and mental burdens on patients and families. In addition, the diagnosis of cancer also causes significant family discordance that can lead to marital problems such as divorce or separation. The aim of this study was to investigate the association and any related gender differences between cancer diagnosis and marital disruption among cancer survivors. Materials and Methods: We used the recent cross-sectional Korea National Health and Nutrition Examination Survey ($4^{th}$ and $5^{th}$; Years 2008-2012). The study participants were 623 married cancer survivors over the age of 19. A multivariate logistic regression analysis was conducted to estimate odds ratios. Results: After adjusting for socioeconomic status and health-related behaviors, the odds ratio of marital disruption among female cancer survivors compared with male cancer survivors was 3.94 (95%CI 1.30-11.94; p=0.02). The odds ratio of marital disruption for the below-average economic level compared with the above-average economic level was 5.64 (95%CI: 1.03-31.02; p=0.05). When compared with the non-smoking cancer survivors, the smoking cancer survivors had an OR of marital disruption equal to 2.94 (95%CI: 1.08-8.00; p=0.03). Conclusions: The findings of this study suggest that the odds of marital disruption among female cancer survivors are higher than those among their male couterparts. Medical practitioners should be sensitive to early signs of marital discord in couples affected by a cancer diagnosis. Early identification and psychosocial intervention might reduce the frequency of divorce and separation and thus improve quality of life and quality of care for cancer survivors.

• 한국지구과학회지
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• 제35권2호
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• pp.97-103
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• 2014

물안정동위원소를 이용하여 지하수와 강우 또는 융설이 하천에 미치는 영향을 정량적으로 분리하는 방법을 동위원소 수문분리법이라고 하며 지난 30년 동안 사용되어 왔다. 오래된 물(지하수)과 새로운 물(강우 및 융설)의 두 성분이 하천에 영향을 미치는 것으로 가정하고 새로운 물과 오래된 물의 주어진 시간동안의 동위원소를 측정하여 각각의 성분에 대한 비율을 결정할 수 있다. 본 연구에서는 동위원소 수문분리법을 수계에 적용할 때 새로운 물의 시간적인 안정동위원소분화를 고려하지 않고 새로운 물의 평균값을 이용하였을 때 계통오차가 발생함을 보였다. 이러한 표준오차의 크기는 (1) 새로운 물이 하천에 많이 기여할수록, (2) 사용된 평균값과 분화된 새로운 물의 안정동위원소 값과 차이가 클수록, 마지막으로 (3) 오래된 물과 새로운 물의 안정동위원소 값의 차이가 작을수록 커진다. 집중 호우로 유출이 증가하거나 봄철에 지면이 아직 녹지 않아 융설이 유출이 되는 경우 새로운 물이 하천에 미치는 영향이 커지게 되어 상대오차 역시 증가한다. 이러한 오차를 줄이기 위해서 각각의 새로운 물, 오래된 물, 하천의 안정동위원소를 같은 시간 간격으로 측정하여 새로운 물이 분화되는 것을 고려한 수문분리법을 수행하는 것을 고려하여야 한다.

• Korean Chemical Engineering Research
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• 제50권2호
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• pp.334-342
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• 2012

새로 개발된 '고액분리 통합이론'의 핵심 개념인 '케이크 첫 입자층이 받는 압력 $p_d$'의 역할을 인식하기 위해, 고압축성 케이크에 대해 다음과 같은 세 가지 고액분리 분야를 새로운 개념으로 분석하였다. 첫째, 침전된 플럭의 케이크 여과에서 여과 대상이 되는 침전 플럭의 두께 계산에서 $p_d$의 역할과, 케이크의 형성 두께 계산에서의 $p_d$의 역할. 둘째, 압착 과정에서의 $p_d$의 역할, 그리고 마지막으로 간섭침전 결과 쌓이는 높이에 미치는 $p_d$의 역할과 간섭침전 과정에서의 $p_d$의 중요성을 보였다. 이로써 고액분리 통합이론의 적용 가능성과, 그에 있어 $p_d$의 중요성을 밝힐 수 있었다. 이 과정을 통하여 케이크 여과, 압착, 간섭침전의 이론적인 새로운 정의가 가능해졌다.

• 한국산업융합학회 논문집
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• 제19권4호
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• pp.176-184
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• 2016

Electrochemical ion exchange method is expected to be one of the most acceptable techniques for the separation of radioactive cations from nuclear wastewater. In this study a thin film of hexacyanoferrate on nickel surface was derivatized chemically in an aqueous potassium-ferricyanide solution. Electrochemical redox behavior of the nickel hexacyanoferrate(NiHCNFe) film electrode was investigated with the use of cyclic voltammetry potentiostated from -100 to 800 mV versus SCE. The electro-reduction characteristics of the NiHCNFe film were examined in the cobalt solutions. The NiHCNFe ion exchanger was more useful at lower concentration, lower temperature, and pH7 of the cobalt solution. The capacity loss of NiHCNFe was 0.018%/cycle that was less than the average loss of 2~3%/cycle of the convective organic exchanger. The 45~55% of the initial cobalt ions was electro-deposited on the NiHCNFe by using continuous recirculating reactor system. As a result, it was found that the electroactive NiHCNFe films showed better performance than the organic resins for the separation of cobalt ion from the aqueous solutions.

• Journal of Microbiology and Biotechnology
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• 제23권8호
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• pp.1092-1098
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• 2013

Cassava constitutes an abundant substrate in tropical regions. The production of butanol in ABE fermentation by Clostridium beijerinckii BA101 using cassava flour (CF) was scaled-up to bioreactor level (5 L). Optimized fermentation conditions were applied; that is, $40^{\circ}C$, 60 g/l CF, and enzymatic pretreatment of the substrate. The batch fermentation profile presented an acidogenic phase for the first 24 h and a solventogenic phase afterwards. An average of 37.01 g/l ABE was produced after 83 h, with a productivity of 0.446 g/l/h. Butanol production was 25.71 g/l with a productivity of 0.310 g/l/h, high or similar to analogous batch processes described for other substrates. Solvent separation by different combinations of fractioned and azeotropic distillation and liquid-liquid separation were assessed to evaluate energetic and economic costs in downstream processing. Results suggest that the use of cassava as a substrate in ABE fermentation could be a cost-effective way of producing butanol in tropical regions.

• 한국가축번식학회지
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• 제12권1호
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• pp.24-30
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• 1988

These experiments were carried out to develop new techniques for In Vitro separatin of X-and Y-bearing spermatozoa. The bull semen was applied to the various Gel-Columns filled with swellen Sephadex G-50 Fine and then elutriated wtih Locke solution (elutriation rate; 1ml/3-4min., 1ml/1-2min.). Elutriated solution was fractionated into 1ml by automatic Fraction Collector and spermatozoa included in each fraction were subjected to the estimation of viability and recovery rate, and to B-body test. The results obtained in these experiments were summarized as follows: 1. When the column size and the elutriation rate were adjusted to 15$\times$1.6cm and 1ml/3-4min., respectively, the highest sperm concentration was obtained from the 8th to the 12th fraction. 2. As a trend, the viability of spermatozoa was improved by chromatography, and the degree of improvement ranged 5 to 10 percentage. 3. The average recovery rate of spermatozoa applied to column was 73.2 percentage and ranged 52.6 to 81.3 percentage. 4. The lowest rate of B-body bearing spermatozoa following chromatography was obtained when the column size and the elutriation rate were adjusted to 15$\times$0.8cm and 1ml/1-2min., respectively.

• 항공우주시스템공학회지
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• 제2권4호
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• pp.1-6
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• 2008

In generally, the regression rate was expressed with average value and oxidizer mass flux in hybrid propulsion system. This can not represent the local value of regression rate along with oxidizer flow direction. In this study, experimental studies were performed with Separation method and Cutting method for measure local regression rate. In axial injection, the local regression rate decreases rapidly with axial location near entrance and increases with axial direction from the leading edge and the empirical formula for local regression rate with function of oxidizer mass flux and location was derived. Swirl injection regression rate has higher value at the leading edge of the fuel and comparatively uniform regression rate at the downstream. Overall regression rate of swirl injection is higher increased about 54 % than regression rate of axial injection.

• 멤브레인
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• 제12권3호
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• pp.158-164
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• 2002

본 연구에서는 반도체 세정공정에서 발생되는 IPA를 재활용하기 위하여 NaA 제올라이트 막을 이용한 투과증발 공정을 검토하기 위한 기초실험을 수행하였다. 공정에 사용한 NaA 제올라이트 막은 전 농도 범위에서 우수한 분리성능을 보였고, 고온조작에서도 분리성능이 매우 우수하였다. 조작온도 50에서 공급원액의 농도가 90 wt%일 때, 투과유속은 약 $1,500 g/m^2/hr$분리계수는 1,000 이상을 얻을 수 있었다. 또한, 연속조작에서 IPA의 탈수농축에 따른 평균 투과유속은 약 $1,000 g/m^2/hr$를 얻을 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제24권7호
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• pp.943-947
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• 2003

We have studied the migration behavior of single-stranded DNA using capillary gel electrophoresis under various conditions. It was found that optimum electric fields should be less than 150 V/cm for the good tradeoff between the separation time and the resolution. It seems that the gel matrix with the combination of different polymer average molecular weights is important to extend the maximum readable DNA bases. The total gel concentration less than 3.1% in the mixed gel system showed good separation efficiency up to 600 bases. The best result was obtained with the poy(ethylene)oxide (PEO) gel concentration of 1.2% of Mr 8,000,000 and 1.8% of Mr 600,000. We observed that the capillary length between 50 cm to 100 cm (effective length) should be employed for the optimization between the total DNA migration time and the maximum readable length. A trizma base-boric acid-ethlyenediaminetetraacetic acid (EDTA) (TBE) buffer was commonly used for DNA sequencing, but we found that 3-[tris(hydroxymethyl)methyl amino]-1-propane sulfonic acid (TAPS) buffer worked as well for the single-stranded DNA separation. Especially, TAPS buffer showed a good resolution for very short DNA bases (1 to 30 bases).