• 암석학회지
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• 제20권4호
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• pp.191-206
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• 2011

청주지역에 분포하는 화강암류 암석에 대한 SHRIMP 저어콘 U-Pb 연대측정, 전암 화학 및 전암 Sr-Nd 동위원소 특성을 살펴보고 이를 대보화강암체의 지구연대학적 및 지화학적 특성과 비교하였다. 청주 화강암체 내부의 섬록암에서 $174{\pm}2Ma$ ($t{\sigma}$), 이를 관입한 흑운모 화강암에서 $170{\pm}2Ma$ ($t{\sigma}$), 그리고 이 두 암 석을 모두 관입하는 산성암맥에서는 $170{\pm}5Ma$ ($t{\sigma}$)의 저어콘 연대가 산출하였다. 각 암석에서 측정한 절대연령은 노두에서 측정한 상대연령과 일치하며, 한반도 중부에 분포하는 대보화강암체에 대한 연대측정결과 (170-175 Ma)와도 부합된다. 청주 화강암체의 주원소 및 미량원소 분석 결과는 한반도 중부에 분포하는 대보화강암류 및 화강섬록암의 분석결과와 잘 일치하며, 섭입대와 관련한 I-type 화강암의 특성을 나타낸다. 하지만, Sr과 Nd 동위원소 조성은 청주 화강암체가 부화된 하부지각물질의 부분용융 산물이거나 지각 물질의 혼염 가능성을 지시한다. 더불어 저어콘의 상속핵 및 포획결정에서 산출되는 2.1, 1.8, 0.8 및 0.4 Ga의 다양한 저어콘 상속핵 연대는 연구지역 주변의 경기육괴와 옥천변성대의 암석들이 동화작용에 의해 혼염 되었을 것으로 판단된다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.327-327
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• 2017

The effect of different seedling ages and transplanting times on the growth and yield of Indica ${\times}$ Japonica rice for noodle processing was evaluated to develop a high yielding cultivation technology for increasing the competition against the imported foreign rice. Four seedling ages (10-, 20-, 30- and 33-day old) of two Indica ${\times}$ Japonica rice cultivars (cvs. Saemimyeon and Palbangmi) and three transplanting dates (May 20, May 30 and June 9) were used in the study. Our results showed that the growth and rice yield of the two cultivars were significantly affected by the different seedling ages and transplanting times. Dry matter production at the panicle heading of the two rice cultivars were generally higher in the 30-day old seedling than the other seedling age treatments and then gradually decreased as the transplanting time was delayed from May 20 to June 9. Similar high panicle number per square meter were recorded at the 30-day old seedling between May 20-May 30 transplanting times. In contrast, other yield parameters that includes spikelet number per panicle, 1,000-brown rice weight, and ripened grain ratio (except for the June 9 transplanting time of Palbangmi) were not significantly affected. The milled rice yield of Saemimyeon was higher than that of the Palbangmi regardless of seedling ages and it was also the highest at the 30-day old seedling with four seedling ages. The milled rice yield of Saemimyeon was only slightly decreased as the transplanting time was delayed from the May 20 to June 9 but Palbangmi had a significantly lower milled rice yield at June 9 transplanting due to the low ripened grain ratio. The result indicates that the most suitable seedling age for the cultivars tested was at 30-day old seedling for noodle processing rice and recommended transplanting times were between May 20 and May 30 for the high rice yield in the Yeongnam plain area.

• 대한방사선기술학회지:방사선기술과학
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• 제33권3호
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• pp.239-243
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• 2010

전립선암을 조기진단하기 위한 선별검사로 혈청 전립선특이항원(serum prostate-specific antigen)과 경직장초음파검사(transrectal ultrasonography)가 널리 쓰이고 있으나 어느 한 가지 방법만으로는 진단적 정확성을 갖지 못하여 상호보완적으로 진단이 이루어지고 있다. 이 연구에서는 혈청 전립선특이항원과 경직장초음파검사에 의해 측정된 전립선용적과의 상관관계를 알아보고자 하였다. 연구의 대상은 2008년 01월부터 2008년 12월까지 D대학병원 영상의학과에서 경직장초음파 검사를 시행한 환자들이다. 총 418명의 성인남성 중 전립선암으로 확진된 13명을 제외한 405명을 대상으로 다음과 같은 결과를 얻었다. 전립선용적과 혈청 전립선특이항원은 연령이 증가함에 따라 함께 증가하는 것으로 나타났으나, 40대의 혈청 전립선특이항원 수치는 다른 연령집단에 비해 가장 낮은 것으로 나타났다. 연령과 전립선용적, 혈청 전립선특이항원은 통계적으로 유의한 양의 상관관계가 있는 것으로 나타났으며, 전립선용적과 혈청 전립선특이항원도 통계적으로 유의한 상관관계가 있는 것으로 나타났다. 이상의 결과를 정리해보면 연령과 전립선용적은 혈청 전립선특이항원의 변화에 관여하였으며, 특히 전립선용적은 연령보다 혈청 전립선특이항원 상승과 더 높은 연관성이 있는 것으로 나타났다. 이는 혈청 전립선 특이항원이 상승된 성인 남자의 평가에서 전립선용적이 중요하게 고려되어야 한다는 것을 시사하며, 경직장초음파검사는 전립선암을 진단하는 훌륭한 보조수단으로써 보다 적극적으로 경직장초음파검사를 활용한다면 전립선암을 조기에 진단하고 적절한 치료를 시행하는데 많은 도움을 줄 수 있을 것으로 생각되어진다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.397-402
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• 2001

Microstructural characteristics such as hydrates and porosity greatly influence the development of concrete strength. In this study, a strength estimation model for early-age concrete considerig, the microstructural characteristics was proposed, which considers the effects of both an increment of degree of hydration and capillary porosity on a strength increment. Hydration modeling and compressive strength test with curing temperature and curing ages were carried out. By comparing test results with estimated strength, it is found that the strength estimation model can estimate compressive strength of early-age concrete with curing ages and curing temperature within a margin of error.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회 논문집(I)
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• pp.309-314
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• 1998

The moisture diffusion and self-desiccation cause the differential drying shrinkage and autogenous shrinkage at early ages, respecitvely. Thus total shrinkage strain includes the differential drying shrinkage and self-desiccation shrinkage. Thus in this study the shrinkage strain was measured at various positions in the exposed concrete and in the sealed concrete the self-desiccation shrinkage was measured. In low-strength concrete, the differential drying shrinkage increases very rapidly, but self-desiccation shrinkage is very small. But high-strength concrete shows the reverse result. And the analytical results for differential drying shrinkage were in good agreement with the test results.

• 천문학회지
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• 제22권1호
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• pp.43-61
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• 1989

The ages of field stars given in the catalogue of Cayrel de Strobel et al. (1985) are derived by the five different methods with combination of theoretical isochrones. By using these ages and metal abundances homogenized by Lee and Choe (1988), the age-metallicity relations are obtained. For disk stars of [Fe/H] > -0.9, the present age-metallicity relations are nearly consistent with those given by Twarog (1980) and Carlberg et al. (1985).

• 아동학회지
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• 제15권2호
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• pp.141-152
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• 1994

The purpose of this study was to investigate the goal and strategy differences in the Social Problem Solving (SPS) according to ages and interaction targets of children. The subjects were 48 children between the ages of 3, 4 and 5 years. Their SPS behavior was observed as it occurred naturally in free play interactions. The data were analysed by one-way ANOVA, Duncan's multiple range, repeated measures, and t-test. The results showed that there were significant goal and strategy differences in SPS behavior according to age and interaction targets of children.

• Journal of Chest Surgery
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• 제24권12호
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• pp.1161-1167
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• 1991

The study consisted of all patients undergoing surgical repair of isolated secundum type atrial septal defect in patients ages 35 years or older for the period from October 1986 to October 1991. ASD was closed with direct suture in all patients. Response to surgery was excellent. Two patients who had atrial fibrillation was taken low-dose warfarin therapy to prevent stroke. All patients survived operation, and improved by at least one New York Heart Association functional classification. An old age was not a contraindication to surgery.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2008년도 추계학술대회
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• pp.139-142
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• 2008

본 연구는 소비연령층에 따른 소비 형태와 기업의 공간마케팅 전략사례를 분석하고자 한다. 이를 통하여 실제 공간마케팅에 활용될 수 있는 방향을 제안할 수 있는 기초적 자료로서의 역할을 하는데 그 목적을 둔

• Advances in concrete construction
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• 제3권4호
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• pp.317-331
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• 2015

This paper presents the effect of different micro-silica (MS) contents of 5, 10 and 15 wt.% as partial replacement of cement on mechanical and durability properties of high volume fly ash - recycled aggregate concretes (HVFA-RAC) containing 50% class F fly ash (FA) and 35% recycled coarse aggregate (RCA) as partial replacement of cement and natural coarse aggregate (NCA), respectively. The measured mechanical and durability properties are compressive strength, indirect tensile strength, elastic modulus, drying shrinkage, water sorptivity and chloride permeability. The effects of different curing ages of 7, 28, 56 and 91 days on above properties are also considered in this study. The results show that the addition of MS up to 10% improved the early age (7 days) strength properties of HVFA-RAC, however, at later ages (e.g. 28-91 days) the above mechanical properties are improved for all MS contents. The 5% MS exhibited the best performance among all MS contents for all mechanical properties of HVFA-RAC. In the case of measured durability properties, mix results are obtained, where 10% and 5% MS exhibited the lowest sorptivity and drying shrinkage, respectively at all ages. However, in the case of chloride ion permeability a decreasing trend is observed with increase in MS contents and curing ages. Strong correlations of indirect tensile strength and modulus of elasticity with square root of compressive strength are also observed in HVFA-RAC. Nevertheless, it is established in this study that MS contributes to the sustainability of HVFA-RAC significantly by improving the mechanical and durability properties of concrete containing 50%less cement and 35% less natural coarse aggregates.