• 한국재료학회지
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• 제4권7호
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• pp.837-844
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• 1994

현재까지 잘 알려진 압출이론식이 생산현장에 응용될 수 있는가를 조사하기 위하여, Al-Si합금을 대상소재로 하여 각 압출이론식에 나타난 유도응력 $K_f$, 변형저항 $K_w$ , Dead Metal Zone(DMZ)의 경각($\alpha$)등을 측정하였으며, 이들 값을 이용하여 최대압출력을 계산하였다. 550ton의 압출기를 이용하여 측정한 최대 압출력과의 비교분석을 행하였으며, 그 결과 이론식에 의해 최대압출력을 계산하기 위해 측정된 유동응력 및 변형저항 값은 신뢰할 수 있을 것으로 사료되었는데, 이것은 0.5이하에서 결정된 변형효율 $\eta _f$로서 판단 할 수 있었다. 최대 압출력은 Si함량이 증가할 수록 증가하게 되나, 압출온도가 증가할 수록 감소하고 있음을 알 수 있었다. Siebel식으로부터 계산된 최대압출력은 본 실험을 통하여 얻어진 최대압출력에 비교적 근접하고 있으나. Geleji식으로부터 계산된 최대압출력은 DMZ의경각 $\alpha$가 $50^{\circ}$일 경우 , 본 실험에 의해 얻어진 실제의 최대압출력에 급접하고 있었다. Geleji의 식은 DMZ의 경각에 매우 민감하고, 대상재료마다. DMZ를 일일이 측정해야 하는 번거로움 때문에 생산현장에서는 Siebel의 식을 이용하는 것이 보다 편리할 것으로 사료된다.

• 한국결정학회지
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• 제15권2호
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• pp.93-98
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• 2004

X-선 회절법을 이용하여 C_{28}H_{41}N_4O_4Br\;{\cdo}t\;2H_2O$의 분자 및 결정구조를 해석하였다. 이 결정의 결정계는 Triclinic이고 공간군은 Pl이며, 단위포 상수 a=9.000(1) $\AA$, b=9.312(3) $\AA$, c=9.344(2) $\AA$, $\alpha=89.37(20)^{\circ},\;\beta=68.81(3)^{\circ},\;\gamma=84.70(4)^{\circ},\;V=726.7(8){\AA},\;T=298K,\;Z=1,\;D_c=1.402Mgm^{-3}$이다. 회절반점들의 세기는 Enraf-Nonius CAD4 Diffractometer로 얻었으며 사용한 X-선은 graphite로 단색화한 $MoK{\alpha}$선$(\lambda=0.71073\;{\AA}$을 사용하였다. 분자구조는 Direct method로 풀었으며, $F_o>4{\sigma}(F_0)$인 2521개의 독립 회절 데이터에 대하여 최소 자승법으로 370개의 변수를 정밀화하여 최종 신뢰도 값 $R=5.95\%$를 얻었다.

• 콘크리트학회논문집
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• 제16권5호
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• pp.581-589
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• 2004

본 논문에서는 일정진폭 휨인장 및 쪼갬인장 반복하중을 받는 콘크리트의 피로신뢰성과 모델제안을 위하여 도로포장에 사용되는 콘크리트를 대상으로 연구하였다. 실험데이터는 2-모수 Weibull 확률분포함수를 사용하여 신뢰성 해석을 수행하였고, 적합도 검정을 통하여 이를 기반으로 한 모델을 제시하였다. 피로실험은 $150 mm{\times}75 mm$ 시험체의 쪼갬인장피로 실험방법과 $150 mm{\times}150 mm{\times}550 mm$ 시험체의 휨인장피로 실험방법을 적용였으며 일정 진폭 피로하중에 대하여 수행하였다. 두 가지의 실험방법에 대하여 응력 수준 90, 80, $70\%$로 변화하여 실험하고 이때 적용한 응력비는 0.1, 하중재하속도 20Hz, 정현파(sine)를 적용하였다. 연구결과 콘크리트 피로데이터의 분산성으로 인하여 보다 정확한 해석을 위해 두 가지의 해석 기준을 설정하여 제시하였으며, 그래픽방법, 모멘트방법 및 최우도법에 의해 2-모수 Weibull의 매개변수 $\alpha$와 u를 계산하고 이를 이용하여 확률밀도함수(P.D.F)와 누적분포함수(C.D.F)를 도시하였다. 또한, Weibull의 확률분포함수를 이용한 신뢰성 해석은 Kolmogorov-Smirnov의 방법을 사용하여 $5\%$의 유의수준에서 적합도 검정을 수행한 결과 채택되는 것으로 나타났다. 이러한 해석에 기초하여 쪼갬인장피로실험과 휨인장피로 실험에 대한 피로모델을 제시하고 응력수준에 따른 피로수명과 200만회 및 1,000만회에서의 피로강도를 산정하여 제시하였으며 국외의 주요 피로모델과 비교하였다.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 1998년도 추계학술발표 논문집
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• pp.143-147
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• 1998

Autonomic and EEG responses of 38 college students were studied during 60-sec long presentation of International Affective Picture System (IAPS )slides evoking, according to subjective reports, negative (disgust, sadness, surprise) and positive (happiness, exciting) emotional. states. Observed were significant heart rate (HR) deceleration, large skin conductance responses (SCR), moderate respiration frequency slowing, reduction of frontal (F 3, F 4 ) and occipital (O 1, O 2 ) fast alpha, and increases of theta, delta and beta relative spectral power values during the first 30 sec of exposure of IAPS pictures. Analysis carried out to differentiate emotion categories according to autonomic responses indicated that observed HR deceleration was larger in magnitude in surprise and sadness than in disgust, SCR amplitude higher in sadness than in disgust. EEC showed significant differences in theta (F 3, F 4 ) and delta (O 1) power increase in disgust vs. happiness, fast alpha (F 3, F 4 ) power was lower in surprise than in happiness, and slow beta power higher. in happiness than in disgust (0 1). Despite some differences. observed within discrete emotion conditions, overall responses pattern of monitored parameters exhibited similar profiles with few variations, most. obvious. in disgust state, which suggests that affective visual stimulation elicits stereotypical responses in a given passive viewing paradigm. However, the magnitude of physiological responses may vary to certain extent across discrete emotional states making it possible to differentiate among particular experimentally-induced emotional states, e.g., disgust vs. sadness by ANS responses or disgust vs. happiness by EEG measures.

• 한국축산식품학회지
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• 제39권5호
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• pp.844-861
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• 2019

Over the last few years, marine environment was found to be a source of surplus natural products and microorganisms with new bioactive secondary metabolites of interest which can divulge nutritional and biological impact on the host. This study aims to assess the possible, inherent and functional probiotic properties of a novel probiotic strain Enterococcus durans F3 (E. durans F3) isolated from the gut of fresh water fish Catla catla. Parameters for evaluating and describing the probiotics described in FAD/WHO guidelines were followed. E. durans F3 demonstrated affirmative results including simulated bile, acid and gastric juice tolerance with exhibited significant bactericidal effect against pathogens Staphylococcus aureus, Salmonella Typhi, Escherichia coli and Pseudomonas aeruginosa. This can be due to the enterocin produced by E. durans F3 strain, which was resolute by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) gel with amplification of the anticipated fragment of a structural gene; enterocin A, followed by antibiotic susceptibility assessment. Effective antioxidant potentiality against ${\alpha}$-diphenyl-${\alpha}$-picrylhydrazyl free radicals including lipase, bile salt hydrolase activity with auto-aggregation and cell surface hydrophobicity was similarly observed. Results are proving the potentiality of E. durans F3, which can also be used as probiotic starter culture in dairy industries for manufacturing new products that imparts health benefits to the host. Finding the potent and novel probiotic strains will also satisfy the current developing market demand for probiotics.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
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• pp.934-939
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• 1998

This study discusses the results of adiabatic temperature rise tests which were performed considering various parameters, such as cement type, water-cement ratio, unit cement weigh, admixtures and placing temperature, which influence the temperature rise(K) and reaction velocity ($\alpha$). Theadiabatic temperature rise models obtained from this study are similar to those of Japan Concrete Institute. The models to calculate temperature rise and reaction velocity could be used the analysis f concrete thermal stress.

• 분석과학
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• 제7권3호
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• pp.329-338
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• 1994

기체 크로마토그래피에 의한 단일 컬럼상에서 천연가스 성분의 용리거동을 알아보았다. 천연가스 성분의 용량인자인 k'값을 결정하기 위하여 불감시간 $t_0$를 동족계열에 의한 외삽법으로 구하였다. 여러 가지 온도에서 $C_1$부터 $C_5$까지 동족계열의 머무름 시간을 탄소수에 대해서 도시하면 어느 한 점에 수렴하게 되는데, 이 점을 $t_0$로 정하였다. n-부탄을 기준으로 온도에 따른 컬럼효율의 변화를 알아본 결과 온도가 증가할수록 컬럼효율은 증가하였으나, 분리시간이 짧은 시료들의 분리도는 감소하였다. 28% DC-200 정지상에서 흡착엔탈피 변화값을 구하였고, 천연가스 성분들의 머무름 메카니즘을 알아보기 위해 log $t_R$, log k' 및 log ${\alpha}$값을 van der Waals 부피(Vw), 분자간 연결지수(X) 및 소수성 계열상수(f)와의 희귀분석을 수행한 결과 log k'과 Vw 및 f가 높은 상관관계를 보여 주었다. 천연가스 성분의 물리적 성질과 물리적 파라미터와의 상관관계를 알아본 결과는 Vw는 분자량과 발열량(${\Delta}H_{comb}$), X는 끓는 점, f는 분자량, 끓는 점 및 발열량과 상관계수가 0.99 이상으로 높은 상관관계를 나타내었다. Vw와 발열량과의 회귀방정식을 이용하여 $C_6$호부터 $C_{10}$까지의 발열량을 예측한 결과 문헌값과 0.2%의 상대오차 범위내에서 일치하였다.

• 동의생리병리학회지
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• 제26권6호
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• pp.874-885
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• 2012

In the present study, the possibility of whether the pharmacological effects of Scutellariae Radix Aqueous Extracts(SR) were favorably changed by report that lipopolysaccharide(LPS)-induced rat acute lung injury was treated with Red-Koji(Monascus purpureus 12002) fermentation. Three different dosages of Red-Koji fermented SR extract(fSR), 125, 250 and 500 mg/kg were orally administered once a day for 28 days before LPS(Escherichia coli 0111:B4) treatments, and then 5 hours after LPS treatment(500 ${\mu}g$/head, intra trachea instillation), all rats were sacrificed. Changes in the body weights, lung weights, pulmonary transcapillary albumin transit, arterial gas parameters(pH, $PaO_2$ and $PaCO_2$) bronchoalveolar lavage fluid(BALF) protein, lactate dehydrogenase(LDH) and proinflammatory cytokine tumor necrosis factor-${\alpha}$(TNF-${\alpha}$), interleukin-$1{\beta}$(IL-$1{\beta}$) contents, total cell numbers, neutrophil and alveolar macrophage ratios, lung malondialdehyde(MDA), myeloperoxidase(MPO), proinflammatory cytokine TNF-${\alpha}$ and IL-$1{\beta}$ contents were observed with histopathology of the lung, changes on luminal surface of alveolus(LSA), thickness of alveolar septum, number of polymorphonuclear neutrophils(PMNs). As results of LPS-injection, dramatical increases in lung weights, pulmonary transcapillary albumin transit increases in $PaCO_2$, decreases in pH of arterial blood and $PaO_2$, increases of BALF protein, LDH, TNF-${\alpha}$ and IL-$1{\beta}$ contents, total cells, neutrophil and alveolar macrophage ratios, lung MDA, MPO, TNF-${\alpha}$ and IL-$1{\beta}$ contents increases were detected with decreases in LSA and increases of alveolar septum and PMNs numbers, respectively as compared with intact control. Especially fSR 125 mg/kg showed quite similar favorable effects on the LPS-induced acute lung injuries as compared with 60 mg/kg of ${\alpha}$-lipoic acid and 250 mg/kg of SR. The results suggest that over 125 mg/kg of fSR extracts showed favorable effects on the LPS-induced acute lung injury mediated by their antioxidant and anti-inflammatory effects. Moreover, increases of the pharmacological effects of SR on LPS-induced acute lung injury were observed by Red-Koji fermentation in this study, at least 2-fold higher.

• Nonlinear Functional Analysis and Applications
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• 제26권4호
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• pp.663-684
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• 2021

In this paper, we present some fixed point results for a general class of nonexpansive mappings in the framework of Banach space and also proposed a new iterative scheme for approximating the fixed point of this class of mappings in the frame work of uniformly convex Banach spaces. Furthermore, we establish some basic properties and convergence results for our new class of mappings in uniformly convex Banach spaces. Finally, we present an application to nonlinear integral equation and also, a numerical example to illustrate our main result and then display the efficiency of the proposed algorithm compared to different iterative algorithms in the literature with different choices of parameters and initial guesses. The results obtained in this paper improve, extend and unify some related results in the literature.

• 약학회지
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• 제45권6호
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• pp.650-655
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• 2001

Carvedilol is a nonselective $\beta$-blocking agent with vasodilating properties that are attributed mainly to its blocking activity at $\alpha$$^{1}$-receptors. Carvedilol is used in the treatment of mild to moderate hypertention and angina pectoris and is often used in combination with other drugs. This study was carried out to evaluate the bioequivalence and pharmacokinetics of two carvedilol 25mg tablet formulations according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty healthy volunteers are enrolled and received a single dose (25mg as carvedilol) of each drug in the fasting state, in a randomized 2-way crossover design. After oral administration, blond samples were collected for a period of 30 hours. Plasma concentrations of carvedilol were determined by a rapid and sensitive HPLC method with spectrofluorometric detection. The major pharmacokinetic parameters such as AU $C_{0-}$30hr/, AU $C_{inf}$ , $C_{max}$, $T_{max}$, $t_{1}$2 / Cl/F and V $_{\beta}$//F were calculated. ANOVA test and t-test were utilized for the statistical analysis of each parameter. The results showed that the differences in AU $C_{0-}$30hr/, $C_{max}$ and $T_{max}$ between two were ~5.66, 1.74 and 0.00%, respectively. Minimum detectable differences ($\Delta$) at $\alpha$=0.05 were less than$\pm$ 20% except $T_{max}$ (8.44, 18.36, and 33.86%, respectively). The 90% confidence intervals of all parameters were within $\pm$20% (-10.60~ -0.72, -9.00~12.49 and -19.81~19.81%, respectively). Therefore, it is concluded that the two formulations are bioequivalent for both the extent and the rate of absorption after single dose administration.ation.ion.ion.ation.ion.n.