• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.18-19
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• 2017

In this study, hardening characteristics and microstructure of blast furnace slag-cement mortar replaced alpha-calcium sulfate hemihydrate were analyzed. As a result of replacing alpha-calcium sulfate hemihydrate with 0, 10, 20, 30%, it was confirmed that the initial and final setting times are faster than that of blast furnace slag-cement mortar. The compressive strength of the specimens containing alpha-calcium sulfate hemihydrate decreased in the range of 42 ~ 76% at age 28 days compared with blast furnace slag-cement mortar. In the case of replacing the alpha-calcium sulfate hemihydrate, the shrinkage did not occur more rapidly than the cement mortar, but the slope of the strain curve showed a linear behavior. The results of scanning electron microscopy images analysis showed that the formation of ettringite was increased at alpha-calcium sulfate hemihydrate replaced mortar.

• Preventive Nutrition and Food Science
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• 제21권3호
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• pp.181-186
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• 2016

This study was designed to investigate the inhibitory effect of Gynura procumbens extract against carbohydrate digesting enzymes and its ability to ameliorate postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. G. procumbens extract showed prominent ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory effects. The half-maximal inhibitory concentration ($IC_{50}$) of G. procumbens extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase was $0.092{\pm}0.018$ and $0.084{\pm}0.027mg/mL$, respectively, suggesting that the ${\alpha}$-amylase inhibition activity of the G. procumbens extract was more effective than that of the positive control, acarbose ($IC_{50}=0.164mg/mL$). The increase in postprandial blood glucose levels was more significantly alleviated in the G. procumbens extract group than in the control group of STZ-induced diabetic mice. Moreover, the area under the curve significantly decreased with G. procumbens extract administration in STZ-induced diabetic mice. These results suggest that G. procumbens extract may help alleviate postprandial hyperglycemia by inhibiting carbohydrate digesting enzymes.

• 한국지반공학회논문집
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• 제23권11호
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• pp.99-107
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• 2007

Hvorslev법이나 Bouwer and Rice법과 같은 선형 커브피팅법은 대수층의 현장 투수계수를 구하기 위해 실시하는 순간변위시험 혹은 순간충격시험(slug test) 결과를 효과적이고 간편하게 해석하도록 한다. 그러나, 대수층의 압축성이 클 경우, 순간변위시험의 결과가 반대수 그래프에서 선형적이지 않고 상향으로 오목한 곡선 형태를 갖게 되므로, 대수층의 압축성을 무시하는 기존의 선형 커브피팅법은 이런 경우에 그대로 적용하기 어렵다. 본 논문에서는 두 선형 커브피팅법을 부분 관통된 우물의 경우에 대하여 비교 분석하여 대부분의 경우에 Hvorslev법이 Bouwer and Rice법에 비하여 과다하게 현장 투수계수를 산정함을 보였다. 또한, 각기 다른 커브피팅 방법에 따른 순간변위시험 해석결과를 무차원 압축 매게변수(${\alpha}$)의 범위 0.001에서 1까지에 대하여 비교 분석하였다. 마지막으로, 압축성이 큰 대수층의 순간 변위시험 해석을 위하여 Chirlin의 방법을 부분 관통된 우물의 형상을 고려할 수 있도록 확장하여 수정된 선형 커브피팅법을 제시하였다. 제안된 방법의 현장 적용성을 검토하기 위해 빙적토 대수층에서 실시된 순간 변위시험 결과를 이용하여 사례분석을 하였다.

• 한국토양비료학회지
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• 제43권4호
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• pp.407-414
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• 2010

토양의 공극 크기별 분포는 토양중 수분의 함량과 수분퍼텐셜의 관계를 나타내는 토양수분특성 자료로부터 계산된다. 그러나 기존의 토양수분특성 측정방법들은 교란된 토양을 이용하거나 코어시료를 채취한다 하여도 동역학적으로 변화하는 현장 토양 공극분포를 반영하는 데는 많은 어려움이 있었다. 또한 이러한 토양수분특성 자료를 얻기 위해서는 많은 시간과 노력이 요구되어 왔다. 따라서 본 연구에서는 교란되지 않은 현장 토양에서 측정한 불포화 수리전도도 자료로부터 토양의 공극 크기별 분포 곡선을 추정하는 이론적 체계를 제시하고자 하였다. 이를 위해 Brooks-Corey와 van Genuchten의 수리학적 모델을 이용하여 토양의 불포화 수리전도도 자료로부터 공극의 크기별 분포를 추정하는 이론적 모델을 전개하였으며, 이러한 이론적 모델에 근거하여 Brooks-Corey와 van Genuchten의 soil parameter들의 변화에 따른 불포화수리전도도와 공극 크기별 분포곡선의 모사하였다. 공극크기별 분포곡선의 모사는 토성별 불포화수리전도도 곡선의 scaling factor 역할을 하는 $K_s$를 1.0 cm $h^{-1}$로 설정하고, 수리학적 모델별로 일정한 경계조건 (Brooks-Corey soil parameters, ${\alpha}_{BC}=1-5L^{-1}$, b = 1 - 10; van Genuchten soil parameters, ${\alpha}_{VG}=0.001-1.0L^{-1}$, m = 0.1 - 0.9)에서 수행하였다. Brooks-Corey 모델을 이용한 공극 크기별 분포곡선의 모사에서는 parameter b가 공극분포곡선의 형태에 영향을 주었으며, ${\alpha}_{BC}$는 공극분포곡선의 민감도에 영향을 주었다. 또 van Genuchten 모델을 이용한 공극 크기별 분포곡선의 모사에서는 ${\alpha}_{VG}$가 scaling factor의 역할을 하였으며, parameter m은 공극분포곡선의 형태에 영향을 주었다. 따라서 경계조건 안에서 불포화 수리전도도 자료로부터 공극의 크기별 분포 모사가 가능하였으며, 토양 parameter들이 토성, 입자분포 등의 물리적 특성을 잘 반영하는 경우 이론적으로 현장 토양의 공극 크기별 분포의 추정이 가능할 것으로 판단되었다.

• 천문학회지
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• 제8권1호
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• pp.3-9
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• 1975

Densities of the three constituent spheroids of the same eccentricity as our earlier model of the Galaxy are assumed to be given by an analytical form of $_{{\rho}i}$(r)=$k_ie^{-m_ir^u{_i}}$, where $k_i,\;m_i$, and ${\alpha}i$ are obtained by comparing with the results of the previous model. Using three values of $_{{\rho}i}$(r) the galactic rotation curve, mass of each spheroid and the whole Galaxy are calculated, and the three dimensional density distribution in the Galaxy is also obtained. The calculated rotation curve of the model Galaxy is in good agreement with the observed curve, and the shape of the cross section of the model Galaxy given by the computed density is very similar to the inferred shape of the spiral galaxies.

• Preventive Nutrition and Food Science
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• 제18권3호
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• pp.163-168
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• 2013

In this study, we investigated the inhibitory effects of Baechu kimchi added Ecklonia cava on the activities of ${\alpha}$-glucosidase and ${\alpha}$-amylase and its alleviating effect on the postprandial hyperglycemia in STZ-induced diabetic mice. Baechu kimchi added Ecklonia cava (BKE, 15%) was fermented at $5^{\circ}C$ for 28 days. Optimum ripened BKE was used in this study as it showedthe strongest inhibitory activities on ${\alpha}$-glucosidase and ${\alpha}$-amylaseby fermentation time among the BKEs in our previous study. The BKE was extracted with 80% methanol and the extract solution was concentrated, and then used in this study. The BKE extract showed higher inhibitory activities than Baechu kimchi extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase. The $IC_{50}$ values of the BKE extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.58 and 0.35 mg/mL, respectively; BKE exhibited a lower ${\alpha}$-glucosidase inhibitory activity but a higher ${\alpha}$-amylase inhibitory activity than those of acarbose. The BKE extract alleviated postprandial hyperglycemia caused by starch loading in normal and streptozotocin- induced diabetic mice. Furthermore, the BKE extract significantly lowered the incremental area under the curve in both normal and diabetic mice (P<0.05). These results indicated that the BKE extract may delay carbohydrate digestion and thus glucose absorption.

• 한국안광학회지
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• 제9권1호
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• pp.69-73
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• 2004

${\alpha}-Al_2O_3$ 단결정의 TSEE와 TSL을 $2{\pi}$비례계수기를 사용하여 측정하였다. ${\alpha}-Al_2O_3$ 단결정을 실온에서 500K 온도범위에서 X선과 자외선(UV)을 조사하였다. X선 조사 후에 3개의 TSEE와 3개의 TSL 봉우리가 관찰되었다. ${\alpha}-Al_2O_3$ 단결정의 TSEE와 TSL 그로우곡선은 여기 원의 종류에 관계없이 잘 대용되고 있음을 보여 주었다. 이 연구에서 우리는 $2{\pi}$ 비례계수기가 ${\alpha}$-입자의 에너지 스펙트럼 분석장치 뿐만 아니라 TSEE와 TSL의 측정에도 유익함을 알 수 있었다.

• Preventive Nutrition and Food Science
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• 제14권1호
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• pp.8-13
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• 2009

This study investigated the hypoglycemic effect of fermented soymilk extract (FSE) in STZ-induced diabetic mice. FSE was prepared via fermentation of soymilk with Bacillus subtilis followed by methanol extraction. The hypoglycemic effect was determined by inhibitory activities against ${\alpha}$-glucosidase and ${\alpha}$-amylase as well as the alleviation of postprandial glucose level. The non-fermented soymilk extract (SE) was used as control in this experiment. FSE showed higher (p<0.05) inhibitory activities than SE against ${\alpha}$-glucosidase and ${\alpha}$-amylase. The $IC_{50}$ values of FSE for ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.77 ancd 0.94 mg/mL, respectively, which were comparable or even superior to those of acarbose (0.79 and 0.68 mg/mL, respectively). In addition, a further suppression on the postprandial blood glucose levels were observed in the FSE than SE group for both STZ-induced diabetic mice and normal mice. Furthermore, FSE significantly lowered the incremental area under the curve (AUC) in the diabetic mice and the AUC in normal mice corroborated the hypoglycemic effect of FSE (p<0.05). Results from this study suggest that FSE may help decrease the postprandial blood glucose level via inhibiting ${\alpha}$-glucosidase and ${\alpha}$-amylase and the usefulness of FSE was proven to be better than SE.

• 동의생리병리학회지
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• 제32권5호
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• pp.341-346
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• 2018

The aims of this study were to evaluate the reliability and validity of the cold and heat pattern identification questionnaire (CHPIQ). From July 2015 to December 2015, 120 participants, university faculties, filled out CHPIQ by the way of self-reporting. Then two Korean medical doctors independently diagnosed them whether they belonged to cold pattern (CP) or not, and heat pattern (HP) or not. We evaluated the internal consistency using Cronbach's alpha coefficient, and the validity using the sensitivity and specificity through receiver operating characteristic-curve. The internal consistency (Cronbach's alpha coefficient) showed 0.754 (CP) and 0.753 (HP). The area under the curve was recorded with 0.884 (CP) and 0.786 (HP). The agreements between CHPIQ and experts were 82.8% (CP) and 72.9% (HP). The sensitivities showed 0.707 (CP) and 0.719 (HP), and the specificities were 0.935 (CP) and 0.736 (HP). This study suggests that CHPIQ is a reliable and valid instrument for estimating cold-heat pattern identification.

• Nutrition Research and Practice
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• 제1권3호
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• pp.184-188
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• 2007

The major goal in the treatment of diabetes mellitus is to achieve near-normal glycemic control. To optimize both fasting blood glucose and postprandial glucose levels is important in keeping blood glucose levels as close to normal as possible. ${\alpha}-Glucosidase$ is the enzyme that digests dietary carbohydrate, and inhibition of this enzyme could suppress postprandial hyperglycemia. The purpose of this study was to test the inhibitory activity of methanol extract of Euonymus alatus on ${\alpha}-glucosidase$ in vitro and in vivo to evaluate its possible use as an anti-diabetic agent. Yeast ${\alpha}-glucosidase$ inhibitory activities of methanol extract of E. alatus were measured at concentrations of 0.50, 0.25, 0.10, and 0.05 mg/ml. The ability of E. alatus to lower postprandial glucose was studied in streptozotocin-induced diabetic rats. A starch solution (1 g/kg) with and without E. alatus extract (500 mg/kg) was administered to diabetic rats by gastric intubation after an overnight fast. Plasma glucose levels were measured at 30, 60, 90, 120, 180, and 240 min. Plasma glucose levels were expressed in increments from baseline, and incremental areas under the response curve were calculated. Extract of E. alatus, which had an $IC_{50}$ value of 0.272 mg/ml, inhibited yeast ${\alpha}-glucosidase$ activity in a concentration-dependent manner. A single oral dose of E. alatus extract significantly inhibited increases in blood glucose levels at 60 and 90 min (p<0.05) and significantly decreased incremental response areas under the glycemic response curve (p<0.05). These results suggest that E. alatus has an antihyperglycemic effect by inhibiting ${\alpha}-glucosidase$ activity in this animal model of diabetes mellitus.