• 한국응용과학기술학회지
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• 제8권2호
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• pp.115-122
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• 1991

Four novel amphoteric surfactants of N-(2-alkylamidoethyl)-N, N-dimethyl ammonioacetates were synthesized. The each reaction between four saturated fatty acids containing 10, 12, 14 and 16 carbon atoms and N, N-dimethylethylene diamine permitted to give the intermediate products, N-(2-alkylamidoethyl)-N, N-dimethylamines. Quaterinzation of these intermediates was permitted to form N-(2-alkylamidoethyl)-N, N-dimethyl, ammonioacetates, whose sturctures were identified by CC, TLC, elemental analysis, IR pectrophotometry and $^1$HNMR spectrometry. The products yielded from 48% to 58%. The isoelectric points were shown in the range of $4.30{\sim}6.64$. It showed a tendency to learn to the acidic site and its range was broadened as increase of the hydrophobic group length. Surface tensions of the aqueous solution in the $10^{-6}{\sim}10^{-1}$mol/l of amidobetaines were measured. and the critical micell concentration(cmc) were shown in the range of $8.37{\times}10^{-6}{\sim}8.96{\times}10^{-2}$mol/l, and ${\Gamma}_{cmc}$ were reduced to 32.3~38.2 dyne/cm. A linear relationship between log cmc and the number of carbon in the hydrophobic alkyl chain was presented by the formula of log cmc=2.38-0.5n, and the contribution-rate of n on the standard free energy change in micellization ${\partial}({\Delta}G^0$$_m)/{\partial}n$, was calulated as -0.5RT.

• 대한토목학회논문집
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• 제13권2호
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• pp.183-190
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• 1993

강우현상은 지역별로 그 특성이 다르고, 장기간을 관측하여 보면 강우특성도 전에 비해서 많이 변화하므로 보다 정확한 배수계획의 수립이나 수공구조물계획을 위해서는 그 지역의 최근의 관측자료까지 포함한 강우특성을 연구하여 적용하는 것이 바람직하다. 따라서 제주지방의 주요 우량관측소(제주시, 서귀포, 성산포)의 최근 20년간(年間)의 자기우량기록지에서 연최대(年最大) 강우량만을 골라서 우량지속기간별로 실측우량을 발췌하였으며, 강우강도식은 일반적으로 많이 사용하고 있는 Talbot형(型), Sherman형(型), Japanese형(型)에다 새로운 Semi-log형(型)을 추가해서 제주지방의 지역별 최적확률 강우강도식을 유도해 본 결과 제주시는 확률년이 3년(年)~5년(年)에는 Japanese형(型), 그 외는 Talbot형(型)이고, 서귀포는 Sherman형(型), 성산포는 Talbot형(型)으로 나타났다.

• Journal of Pharmaceutical Investigation
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• 제34권1호
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• pp.49-55
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• 2004

To develop a aceclofenac soft capsule, four preparations with various solubilizers were prepared and their dissolution test was carried out. Among four preparations tested, a preparation with ethanolamine was selected as a formula of aceclofenac soft capsule (Clanza $S^{TM}$), since it showed the fastεst dissolution rate. Bioequivalence of aceclofenac tablet, $Airtal^{TM}$ (Dae-Woong Pharmaceutical Co., Ltd.) and aceclofenac soft capsule, Clanza $S^{TM}$ (Korea United Pharmaceutical Co., Ltd.) was evaluated according to the guideline of KA Fourteen normal male volunteers (age 20 - 25 years old) were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After oral administration of one tablet or capsule containing 100 mg of aceclofenac, blood was taken at predetermined time intervals and the concentration of aceclofenac in plasma was determined with an HPLC method under UV detector The pharmacokinetic parameters ($C_{max}$ and $AUC_t$) were calculated and ANOVA was utilized for the statistical analysis of parameters using logarithmetically transformed $AUC_t$, $C_{max}$ and $T_{max}$. The results showed that the differences in $AUC_t$, $C_{max}$ and $T_{max}$ between Aral tablet and Clanza soft capsule were 2.89%, 0.18% and 43.0%, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(15) (e.g. log(0.81) -log(1.23) ad log(0.89) -log(1.4)) fo $AUC_t$ and $C_{max}$, respectively. Thus, the criteria of the KFDA guidelines for the equivalence was satisfied, indicating that Clanza $S^{TM}$ soft capsule is bioequivalent to$Airtal^{TM}$ tablet.

• 한국환경과학회지
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• 제10권6호
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• pp.445-450
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• 2001

This study was carried out In Investigate the correlation between toluene In air and hippuric acid In human urine, which 1.: based on the results of the health check-in and the measure of working environment, was investigated for two years. The concentration of toluene in air for the five working places in Yang-San area were ranged from 39.05±10.31 ppm to 4.04±3.38ppm and the mean value of those was 16.89±14.76ppm. The mean value was 16.89±14.76ppm which is below the permissible limit of toluene. The concentration of hippuric acid(HA) In the worker's urine were between 0.47g/ℓ and 0.76g/ℓ. There was mutual correlation (Υ=0.94) between the concentration of toluene in air and that of hippuric acid in urine. In case of male workers, the mean value of hippurlc acid In urine was 0.56g/ f and the female workers was 0.57g/ℓ that showed higher than the male's. However, there was no relationship between the workshop and the distinction of sex. From the mean value of toluene in air(T) and that of hippuric acid(H), we obtained the formula, Η=0.3logΤ+0.235.

• 한국농공학회지
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• 제12권1호
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• pp.1854-1860
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• 1970

Results of this study on the influence of percent passing of No. 200 sieve on soil compaction are as follows; 1. The higher maximum dry density of soil is, the lower optimum moisture content is. Maximum dry density is highest value and optimum moisture content is the lowest value in twocases that percents of No. 200 sieve are 30% in soils of which percents retained on No. 10 sieve are 5% and 10% respectively. 2. Maximum dry density increases according as uniformity coefficient increase. Maximum dry density is the highest when uniformity coefficient is approximately 300 in soil of which maximum diameter is 4.76mm. 3. Maximum dry density has a tendency to become large according as value of Cu Caincrease. Correlation between maximum dry density and $Log_{10}$(CuCa) shows straight line. 4. Maximum dry density increases according as n increase and reaches the peak when n equal 0.35 in condition that the index of talbot formula n is less than 0.35 in soil of which maximum diameter is 4.76mm. 5. Maximum dry density has a tendency to increase according as value of Cg $(Cg=\frac{P_{50}^2}{P_{10}{\times}{P_{200}}$) decrease.

• 한국산림과학회지
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• 제69권1호
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• pp.6-12
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• 1985

수간석해(樹幹析解)를 위한 계산시간(計算時間)을 크게 단축(短縮)시키면서 정확(正確)한 계산결과(計算結果)를 얻을 수 있는 전산화(電算化)프로그램을 BASIC어(語)로 개발(開發)하였다. 원판측정자료(圓板測定資料) 등은 사용자(使用者) 자신이 전산기(電算機)에 직접 입력(入力)시킬 수 있도록 하였으며, 자료목록(資料目錄), 단면적(斷面績), 령급별(齡級別) 수고(樹高), 각종 성장량(成長量)과 성장률(成長率) 등이 출력(出力)되도록 하였다. 이 때, 통나무 재적(材積)은 Huber식(式)에 의하여 계산(計算)하였으며 성장률(成長率)은 Pressler식(式)에 의하여 계산(計算)하였다. 본(本) 프로그램의 목록(目錄)은 부록(附錄) I과 같다.

• 천문학논총
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• 제4권1호
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• pp.16-30
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• 1989

We present recent data of absolute measurements of flux emmitted in the visible continua of some galactic Wolf-Rayet stars, carried out by means of a two-channel scanner built up cooperatively by the Observatoire de Lyon and the Laboratoire d'Astronomie Spatiale. Our measurements lead to the determination of stellar angular diameters which enable us to compute log $L_*/L_{\odot}$ and to locate the WR stars in the HR diagram: The WR stars are cooler than the zero age main sequence (ZAMS) and the WN7, WN8 types appear more luminous than other subclasses. The stellar wind terminal velocities, $V_{\infty}$, deduced from the empirical relation of the effective temperatures by Underhil1(1983) and $V_{\infty}$ adopted from the work of Willis(1982) show about 2,000km/s. We derived the rate of mass loss for the program stars from the formula, $\dot{M}={\varepsilon}(T_{eff})\;L/V_{\infty}{\cdot}c$ by using the obtained effective temperatures, luminosities and $V_{\infty}$ in this work. Their values range from $\dot{M}=1.4{\times}10^{-5}$ to $\dot{M}=5.8{\times}10^{-5}\;\dot{M}_{\odot}/yr$.

• 물과 미래
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• 제8권1호
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• pp.80-88
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• 1975

In this paper the authors established the best fit distribution function by applying the concept of probabiaity to the annual minimum flow of nine areas along the Nakdong river basin which is one of the largest Korean rivers and calculated the probable minimum flow suitable to those distribution function. Lastly, the authors tried to establish the best method to estimate the probable minimun flow by comparing some frequency analysis methods. The results obtained are as follows (1) It was considered that the extremal distribution type III was the most suitable one in the distributional types as a result of the comparision with Exponential distribution, Log-Normal distribution, Extremal distribution type-III and so on. (2) It was found that the formula of extremal distribution type-II for the estimation of probable minimum flow gave the best result in deciding the probable minimum flow of the Nakdong river basin. Therfore, it is recommended that the probable minimum flow should be estimated by using the extremal distribution type-III method. (3) It could be understood that in the probable minimum flow the average non-excessive probability appeared to be $Po{\fallingdotseq}1-\frac{1}{2T}$ and gave the same values of the probable variable without any difference in the various methods of plotting technique.

• 한국식품위생안전성학회지
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• 제23권2호
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• pp.157-162
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• 2008

열수(Hot water)를 이용 조제분유 및 선식 준비 시 살균효과를 실험한 결과 $60^{\circ}C$ 이상에서 살균 효과를 나타내었으나 조제분유와 선식에 열수를 가하였을 때 발생하는 온도 저하와 조제분유 및 선식 등의 분말 식품에서 biofilm을 생산하여 내열성이 증가되는 E. sakazakii의 특성을 고려하여 $70^{\circ}C$ 이상의 열수로 조제분유 및 선식 등을 용해하여야 할 것으로 판단된다. 마이크로웨이브를 이용 E. sakazakii의 살균 효과를 실험한 결과 E. sakazakii를 제어하기 위하여 100 mL의 경우 90초 이상 가열하거나 온도측정이 곤란한 경우에는 최초 끓는 시점까지 가열한 후 냉각하여 섭취하여야할 것으로 조사되었다. 용해된 조제분유 및 선식의 저장 안정성을 평가하기 위해 $5{\sim}35^{\circ}C$에 48시간 동안 보관하며 E. sakazakii의 성장곡선을 실험한 결과 $5^{\circ}C$, $10^{\circ}C$ 냉장온도에서는 48시간까지 증식이 미약하였다. 그러나 냉장 온도에서 사멸하지 않고 미약하게 증식하는 E. sakazakii의 특성을 고려하여 조제분유 및 선식의 냉장 보관은 24시간 이내로 제한하여 섭취하여야 할 것으로 판단된다.

• 한국정보과학회논문지:시스템및이론
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• 제30권5_6호
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• pp.324-329
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• 2003

Diffie-Hellman 키분배 시스템과 타원곡선 암호시스템과 같은 공개키 기반 암호시스템은 GF(2$^{m}$ ) 상에서 정의된 연산, 즉 덧셈, 뺄셈, 곱셈 및 곱셈 역원 연산을 기반으로 구축되며, 이들 암호시스템을 효율적으로 구현하기 위해서는 위 연산들을 고속으로 계산하는 것이 중요하다. 그 중에서 곱셈 역원이 가장 time-consuming하여 많은 연구 대상이 되고 있다. Format 정리에 의해$\beta$$\in$GF(2$^{m}$ )의 곱셈 역원 $\beta$$^{-1}$은 $\beta$$^{-1}$=$\beta$$^{2}$sup m/-2/이므로 GF(2$^{m}$ )의 임의의 원소에 대해 곱셈 역원을 고속으로 계산하기 위해서는, 2$^{m}$ -2을 효율적으로 분해하여 곱셈 횟수를 감소시키는 것이 가장 중요하며, 이와 관련된 알고리즘들이 많이 제안되어 왔다 이 중 Itoh와 Tsujii가 제안한 알고리즘[2]은 정규기저를 사용해서 필요한 곱셈 횟수를 O(log m)까지 감소시켰으며, 또한 이 알고리즘을 향상시킨 몇몇 알고리즘들이 제안되었지만, 분해과정이 복잡하다는 등의 단점이 있다[3,5]. 본 논문에서는 실제 어플리케이션에서 주로 많이 사용되는 m=2$^{n}$ 인 경우에, 인수분해 공식 x$^3$-y$^3$=(x-y)(x$^2$＋xy＋y$^2$)와 정규기저론 이용해서 곱셈 역원을 고속으로 계산하는 알고리즘을 제안한다. 본 논문의 알고리즘은 곱셈 횟수가 Itoh와 Tsujii가 제안한 알고리즘 보다 적으며, 2$^{m}$ -2의 분해가 기존의 알고리즘 보다 간단하다.