• KSBB Journal
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• 제25권1호
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• pp.85-90
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• 2010

An ion selective microelectrode (ISME) was fabricated to measure concentrations of ammonium (${NH_4}^+$-N) and nitrate (${NO_3}^-$-N) according to the depth of nitrifying biofilm. The limits of detectability and validity of results were investigated to evaluate the ISME. The electromotive force (EMF) was directly proportional to the ion concentration, and average detection limits of ${NH_4}^+$ and ${NO_3}^-$ ISME were $10^{-5.14}$ and $10^{-5.18}$ M, respectively. The concentrations of ${NH_4}^+ $-N and ${NO_3}^-$-N in various depths on the nitrifying biofilm were measured by the ISME. When a modified Ludzack-Ettinger (MLE) process was operated at an HRT of 6 h, concentration gradients of ${NH_4}^+$-N in the bulk solution and biofilm at depths of $100\;{\mu}m$ decreased by $70\;{\mu}M$, while ${NO_3}^-$-N increased by $101\;{\mu}M$ and remained constant thereafter. At an HRT of 4 h, concentration gradients of ${NH_4}^+$-N at depths of $500\;{\mu}m$ decreased by $160\;{\mu}M$ and ${NO_3}^-$-N increased by $162;{\mu}M$ and remained constant thereafter. As HRT decreased, the concentration gradients of ${NH_4}^+$-N and ${NO_3}^-$-N between bulk solution and biofilm was higher due to the increase of nitrogen load. Also, the concentration gradients of the ${NH_4}^+$-N and ${NO_3}^-$-N of biofilm in the second aerobic tank were lower than those of the first aerobic tank, suggesting differences of nitrogen load and concentrations of DO between the first and second aerobic tank.

• Biomolecules & Therapeutics
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• 제20권2호
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• pp.183-188
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• 2012

In this study, we examined the estrogenic activity of bavachin, a component of Psoralea corylifolia that has been used as a traditional medicine in Asia. Bavachin was purified from ethanolic extract of Psoralea corylifolia and characterized its estrogenic activity by ligand binding, reporter gene activation, and endogenous estrogen receptor (ER) target gene regulation. Bavachin showed ER ligand binding activity in competitive displacement of [$^3H$] $E_2$ from recombinant ER. The estrogenic activity of bavachin was characterized in a transient transfection system using $ER{\alpha}$ or $ER{\beta}$ and estrogen-responsive luciferase plasmids in CV-1 cells with an $EC_{50}$ of 320 nM and 680 nM, respectively. Bavachin increased the mRNA levels of estrogen-responsive genes such as pS2 and PR, and decreased the protein level of $ER{\alpha}$ by proteasomal pathway. However, bavachin failed to activate the androgen receptor in CV-1 cells transiently transfected with the corresponding receptor and hormone responsive reporter plasmid. These data indicate that bavachin acts as a weak phytoestrogen by binding and activating the ER.

• 펄프종이기술
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• 제47권2호
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• pp.1-8
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• 2015

Disposable diaper has been used in order to handle urine and feces conveniently. At present the amount of disposable diaper waste increases gradually. Incineration and landfill have been the only ways to dispose of disposable diapers. However, if they are disposed by landfill, decomposition will take more than one hundred years. In addition, another way of dispose incineration has caused air pollution. Therefore, it is necessary to study recycling process for disposable diaper since plastic and wood fibers of diaper are useful materials to recycle. In this study, pulping condition of disposable diaper waste was studied in order to effectively separate the components. Recovery rates of plastic and fibers were analyzed under different pulping conditions. It was found that optimum pulping consistency was 5%, time was 60 minutes, temperature was $50^{\circ}C$, and cut size is $21cm{\times}21cm$. The recovery rate of plastic and fibers can be achieved above 70% under the optimum pulping condition.

• 한국의류학회지
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• 제29권8호
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• pp.1102-1113
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• 2005

The propose of this study is to develop the optimal sizing system of ready-to-wear f3r elementary school girls using a newly invented statistical technique. The body measurements was classified by the method that equalizes the distribution of the subjects using the probability density function, to theoretically systemize a method to determine a size range of ready-to-wear for elementary school girls between 6 to 12 years old. The statistical method were 1) The total of 11 height groups, which size interval from one another is 6 cm that is an average height gap between each age. 2) In order to determine an approximate figure (m ${\times}$ n) to establish the appropriate sizes far each height group that fit to the combinations of bust and hip girth, which based on their means and standard deviations on the probability density curve to produce the standard normal distribution. 3) m and n were aligned by 4cm -the grading increments used for patterns making- and determined the size ranges by confirming the approximate figures of m and n. 4) The representative values were determined by an area ratio calculated by dividing the area determined from the range of bust and hip girth with the representative value. Considering the characteristics of subjects' distribution, the area ratios was used. 5) Weight was calculated by seeking a growth exponent for each age and multiplying it by the number of girls that fit to each size range. As sections that show the highest weight are more likely sought by the consumers, these sections were determined as the optimal size standards. 6) This optimal sizing system consists of sizes determined by the optimal size standards and its sizes are marked with height, bust and hip girth.

• 한국광학회지
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• 제31권3호
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• pp.148-154
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• 2020

본 논문에서는 주기적인 구멍배열(periodic hole array, PHA) 패턴을 가진 나노금속구조 컬러필터의 문제점인 입사광의 각도에 따른 컬러필터 중심파장의 이동을 해결하기 위해 새로운 구멍 패턴인 polyperiodic hole array (PPHA)를 제시한다. 먼저 녹색파장대역 컬러필터를 만들기 위해 구멍의 직경과 주기를 정했으며 propagation length와 skin depth를 고려해 단위셀의 크기, 금속과 유전체의 두께를 설정했다. PPHA 패턴을 만들기 위해 주기적인 구멍배열을 국부적으로 회전시켜 전체적으로는 비주기적이지만 부분적으로 주기적인 패턴을 만들었다. 그 결과 PHA 패턴과 대비하여 PPHA 패턴 나노금속구조 컬러필터는 입사광각이 0°에서 30°까지 증가하였을 때 파장의 이동도가 최대 40% 개선되었다. 본 연구를 통해 나노금속구조 컬러필터의 성능을 향상시킬 수 있으며 디스플레이, 이미지 센서 등 이미징 디바이스 분야에 접목시켜 산업적으로 활용할 수 있을 것으로 예상한다.

• 대한화학회지
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• 제36권2호
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• pp.185-190
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• 1992

사염화탄소 속에서 대단히 묽은 티오아미드 및 티오아미드-DMSO 용액의 $ν_{\alpha}$ + Amide II 조합띠에 대한 근적외선 스펙트럼을 $5^{\circ}C$ 와 $55^{\circ}C$ 사이에서 얻었다. 이 조합띠는 두 개의 Lorentzian-Gaussian product 함수로 분해되며, 각각은 단체 티오아미드 및 1 : 1 티오아미드-DMSO 복합체로 확인되었다. 티오아세트아미드(TA)와 DMSO 사이의 수소결합은 티오프로피온 아미드(TPA)와 DMSO 사이의 수소결합보다 약간 강하며 $CCl_4$ 속에서 TA-DMSO와 TPA-DMSO 1: 1 복합체에 대한 ${\Delta}H^{\circ}$는 각각 -15.3 kJ${\cdot}$$mol^{-1}$ 및 -14.2 kj${\cdot}$$mol^{-1}$이었다.

• 아동학회지
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• 제31권4호
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• pp.61-74
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• 2010

The present study sought to examine parent-child relational factors associated with young child's language abilities according to socioeconomic status. To do so, the survey responses of 2,269 parents of 0- to 5- year-olds, taken from research on the Actual Condition of Korean Children and Youth were analyzed. The results were as follows : (1) Low-income families had significantly fewer toys related to literacy than middle and upper-income families. (2) There were fewer instances of parent-child play interactions as well as lower scores of parenting styles and beliefs in low-income families than in middle and upper-income families. (3) Although there was no difference in terms of language abilities from 0- to 1-year-old children according to socioeconomic status, 2-, 3-, 4- and 5-year-old children from low-income families exhibited significantly lower language scores than children from middle- and upper-income families. (4) Toys related to literacy and parent-child relational factors were positively related to children's language abilities. (5) It can be further argued that toys related to literacy and parent-child relational factors clearly predict children's language abilities.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.925-928
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• 2008

최근 내진부재 및 기존 구조물의 내진보강요소의 손상제어(Damage tolerance)성능을 충족할 수 있는 변형경화형 시멘트 복합체(Strain-hardening cement composites, SHCC)의 개발 및 활용 연구가 진행 중이며, 하이브리드화에 따른 경제성 및 성능향상 가능성도 보고되고 있다. 그러나 이러한 우수한 성능을 갖는 SHCC 재료가 실구조물의 보수/보강재 및 내진보강부재에 적용되기 위해서는 우수한 인장성능 발현뿐만 아니라, 보강섬유의 단가를 고려한 경제적 효과(Economical efficiency) 및 시공성 (Workability)이 요구된다. 따라서 본 연구에서는 SHCC를 내진부재 및 보강재료로써 적용하기 위한 연구의 일환으로 합성섬유를 하이브리드하여 혼입시 휨 및 인장강도, 변형능력 등 거동특성을 분석함으로써 각 보강섬유의 인장강도 탄성계수 등 기계적 특성과 혼입율에 따른 재료성능과의 상관관계를 비교 분석하여 평가하고자 한다. 또한 물시멘트비를 변수로 하여 시멘트 복합체의 강도특성과 보강섬유의 부착특성 및 균열제어성능을 규명하고자 한다. 이러한 결과를 근거로 향후 SHCC 재료의 실구조물 적용시 요구성능 및 경제성을 고려한 재료배합에 관한 기초자료를 제시하고자 한다.

• 한국양식학회지
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• 제22권1호
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• pp.34-41
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• 2009

전라남도 여수시 소라면 여자만에서 2002년 1월부터 12월까지 채집된 꼬막의 생식소 발달과 생식주기를 조직학적으로 조사하였다. 꼬막은 자웅이체로 난소는 많은 난소 소낭(oogenic follicle)으로 이루어져 있으며, 정소도 많은 정소 소낭(acinus)으로 구성되어 있다. 생식소지수(GI)는 6월에 연중 최고 값을 나타내었고, 그 후 감소하여 8월에 최저 값을 나타내었다. 비만도지수(CI)는 7월에 연중 치고 값을 보였고, 그 후 감소하여 9월에 최저를 나타냈다. 꼬막의 생식주기는 초기 활성기($3{\sim}5$월), 후기 활성기($4{\sim}6$월), 완숙기($5{\sim}7$월), 방출기($7{\sim}8$월) 그리고 회복 및 휴지기($9{\sim}3$월)의 연속적인 발달 단계로 구분되었으며, 주 산란기는 $7{\sim}8$월로 조사되었다. 암 수 성비는 1:1로 유의한 차를 보이지 않았다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.317-320
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• 2008

최근 재건축 및 재개발에 따른 폐콘크리트의 발생량이 점차 증가하고 있으며 이러한 폐콘크리트의 환경적 처리 방안으로 순환골재의 사용이 제시되고 있다. 그러나 기존연구에서는 실험실에서 낮은 품질의 순환골재를 사용하거나 작은 크기의 부재만을 연구하는 한계를 지니고 있다. 따라서 본 연구에서는 순환 잔골재의 사용에 따른 철근콘크리트 보의 휨거동 특성을 평가하고자 순환잔골재와 재생잔 골재를 사용하여 총 3개의 실험체를 제작하였다. 실험을 통하여 보의 균열 및 파괴양상에 대하여 휨거동 특성을 평가하고 순환잔골재 및 재생잔골재를 사용한 철근콘크리트 보의 휨성능을 KCI 규준식과 비교하였다.