• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 춘계총회 및 제22차 학술발표회
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• pp.105.1-105
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• 2003

This study was performed to develop the precise and rapid method to distinguish the blended sesame oil through the electronic nose analysis. The sesame oil was blended with corn oil at the ratio of 95:5, 90:10, 80:20(w/w), respectively. Samples were then analyzed by gas chromatography, SPME-GC/MS and the electronic nose composed of 12 metal oxide sensors. The sensetivities(delta Rgas/Rair) of sensors by electronic nose was carried out with principal component analysis(PCA). The proportion of first principal component showed 98.76%. In this study, the electronic nose analysis could be used as a competent method to classify for genuine sesame oil.

• Communications for Statistical Applications and Methods
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• 제10권1호
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• pp.135-144
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• 2003

This work is concerned with comparison of the recently developed disparity measures for the partial association model in three dimensional categorical data. Data are generated by using simulation on each term in the log-linear model equation based on the partial association model, which is a proposed method in this paper. This alternative Monte Carlo methods are explored to study the behavior of disparity measures such as the power divergence statistic I(λ), the Pearson chi-square statistic X$^2$, the likelihood ratio statistic G$^2$, the blended weight chi-square statistic BWCS(λ), the blended weight Hellinger distance statistic BWHD(λ), and the negative exponential disparity statistic NED(λ) for moderate sample sizes. We find that the power divergence statistic I(2/3) and the blended weight Hellinger distance family BWHD(1/9) are the best tests with respect to size and power.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.1041-1044
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• 2008

The addition of chemical inert filler in blended cement, such as limestone or chemical inert silica fume, will produce a physical effect on cement hydration. Due to the high surface area of inert filler in the mixtures, it provides sites for the nucleation and growth of hydration products, thus improving the hydration rate of cement compounds and consequently increasing the strength at early age. This paper proposes a model of hydration of Portland cement blended with chemical inert filler. This model considers the influence of water to cement ratio, cement particle size, cement composition and addition of chemical inert filler on hydration. The heat evolution, degree of hydration and porosity are obtained as accompanied results in hydration process. The prediction results agree well with experiment results.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.143-144
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• 2023

This study aimed to evaluate the feasibility of estimating the setting time and compressive strength in Ternary Blended Concrete(TBC) using Settimeter, Strength meter, and Hybrid meter. It was determined that the hardness values at the initial setting time and final setting time of Settimeter, Hybrid meter, and at the 5 MPa of Strength meter were not affected by the mixing ratio of TBC. However, future studies need to consider the errors caused by the instability of the measurement surface during condensation and the state of the measurement surface after hardening.

• 한국건축시공학회지
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• 제22권3호
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• pp.327-336
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• 2022

국내대학 교육은 코로나19 팬데믹으로 온라인교육의 비중이 급격히 증가하였다. 본 연구는 온라인교육을 적극적으로 활용한 건축시공학 블렌디드러닝 교육과정을 개발하였다. 코로나19 팬데믹 이후, 국내대학 건축시공 분야의 교과목 운영 실태를 분석하였다. 온라인교육의 비중이 약 66.1%, 대면강의가 약 33.9%로 조사되었다. 온라인교육의 비중이 급격히 증가한 것으로 분석되었다. 건축시공학 교과목의 블렌디드러닝 교육과정을 개발하였다. 개발된 교육과정은 일주일 단위의 교육절차, 15주차별 교육내용을 중심으로 하였다. 본 연구에서 제시한 교육과정을 대학에서 적용할 때는 교수자의 교육목표와 학습자의 학습능력 등에 따라 융통성있게 적용할 수 있을 것이다.

• 한국자동차공학회논문집
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• 제19권4호
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• pp.130-136
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• 2011

This study describes the effect of EGR rate on the combustion and emissions characteristics of a four cylinder CRDI diesel engine using biodiesel (soybean oil) blended diesel fuel. The test fuel is composed of 30% biodiesel and 70% ULSD (ultra low sulfur diesel) by volumetric ratio. The experiment of engine emissions and performance characteristics were performed under the various EGR rates. The experimental results showed that ignition delay was extended, the maximum combustion pressure and heat release gradually were decreased with increasing EGR rate. Comparing biodiesel blended fuel to ULSD, the injection quantity of biodiesel blended fuel was further increased than ULSD. The emission results showed that $NO_x$ emission of biodiesel blended fuel becomes higher according to the increase of EGR rate. However, in the case of biodiesel blended fuel, HC, CO and soot emissions were decreased compared to ULSD.

• 복식문화연구
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• 제12권6호
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• pp.945-952
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• 2004

Shrink-resist effects and properties of the knitted fabrics from wool/acrylic(W/A) fiber blends were determined to find out an optimal blending ratio keeping the quality properties of wool products. The test fabrics were knitted by a weft knitting machine with all needle knitting structure ($0{\times}0$ rib) under the same knitting conditions with five different types of yarns: $W100\%,\;A100\%$, and W/A blended yarns(70/30, 50/50, 30/70). Shrinkage during repeated washing, electrostatic propensity, thermal resistance and pilling propensity of W/A knits. The shrink resistance was significantly enhanced on repeated washing of W/A knits, especially, over $50\%$ acrylic blended knits. Addition of strong physical force and alkali detergent applied in this washing experiment brought about superior effects with the low shrinkage rate although it was very severe washing conditions for wool fabrics. The results from the washing experiment implies that W/A blend knits can be machine washed at individual households with other ordinary laundry. There was some changes and variation found in thermal resistance, electrostatic propensity, and pilling. W/A 50/50 blended knits did not bring serious changes to other physical properties comparing with original wool, which helps consumers care wool knitted clothes more conveniently.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.113-117
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• 2000

The objective of this study is to find the long-age strength property and the compressive strength of age which is used as the specified concrete strength. The W/W ratio (45%, 50%, 55%, 60%) fine aggregate of useful river sand or blended sand(river sane : sea sand=1:1) were chosen as the experimental parameters. the experimental results show that pH(it means the material segregation resistance) & suspension were increased larger, so W/C become larger, and slump flow was increased as W/C increased (except W/C=60%), air-contents were decreased as W/C became increase and all of this results are satisfied with the under of 40%. The compressive strength ( a case use only river sand as fine aggregate) is showed less than the case of blended asnd. Because the unit weight of the blended sand is more heavy than the unit weigh of the river sand. The results of the case which haven been used only river sand, and the case have been used blended sand), both case have considered W/C. So it's possible to use the compressive strength of age 28 day like the case of plain concrete.

• 한국구조물진단유지관리공학회 논문집
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• 제24권2호
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• pp.41-49
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• 2020

상온에서 발생하는 1, 2성분계 무시멘트 콘크리트의 강도저하 문제를 개선하기 위해 시멘트를 실리카 흄, 플라이애시, 고로슬래그 미분말로 치환한 3성분계 무시멘트 콘크리트의 슬럼프와 압축강도 특성을 통해 비교분석을 실시하여 다음과 같은 결론을 얻었다. 3성분계 무시멘트 콘크리트는 2성분계에 비해 높은 압축강도를 나타냈으며 실리카 흄을 10% 혼입한 경우 슬럼프 감소가 적은 것으로 나타났다. 또한, 삼각조성도를 통해 슬럼프 및 압축강도 수준별 각 무기결합재의 적정 구성비율 범위를 제시하였다.

• Advances in concrete construction
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• 제11권2호
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• pp.99-109
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• 2021

Slag blended concrete is widely used as a mineral admixture in the modern concrete industry. This study shows an optimization process that determines the optimal mixture of air-entrained slag blended concrete considering carbonation durability, frost durability, CO2 emission, and materials cost. First, the aim of optimization is set as total cost, which equals material cost plus CO2 emission cost. The constraints of optimization consist of strength, workability, carbonation durability with climate change, frost durability, range of components and component ratio, and absolute volume. A genetic algorithm is used to determine optimal mixtures considering aim function and various constraints. Second, mixture design examples are shown considering four different cases, namely, mixtures without considering carbonation (Case 1), mixtures considering carbonation (Case 2), mixtures considering carbonation coupled with climate change (Case 3), and mixtures of high strength concrete (Case 4). The results show that the carbonization is the controlling factor of the mixture design of the concrete with ordinary strength (the designed strength is 30MPa). To meet the challenge of climate change, stronger concrete must be used. For high-strength slag blended concrete (design strength is 55MPa), strength is the control factor of mixture design.