• 한국재료학회지
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• 제4권3호
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• pp.259-267
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• 1994

프로판($C_3H_8$)을 반응가스로 사용하여 등온 저압화학기상침투법(low-pressure chemical vapor infiltration)으로 탄소/탄소 복합재료를 치밀화 할 때 반응온도, 반응가스농도, 가스유량, 반응압력 등의 제조공정변수들이 치밀화에 미치는 영향을 알아보기 위하여 실험계획법(Rdbust design method)에 의한 실험을 행하였다. 1회의 등온 저압화학기상침투 실험으로 탄소/탄소 복합재료의 부피 밀도와 표면과 내부의 부피 밀도의 차이를 특성치(characteristic value)로 한 실험계획법의 분산분석(analysis of variance)에 의하면 반응온도, 반응가스농도, 가스유량 등의 제고공정변수가 치밀화에 기여도가 높으며, 반응압력의 기여도와 제조공정변수들의 교호작용(interaction)에 의한 기여도는 낮은 것으로 나타났다. 반응온도가 $1100^{\circ}C$, 반응가스농도가 100% $C_3H_8$, 가스유량이 100 SCCM, 반응압력이 5torr인 조건에서 탄소/탄소 복합재료는 가장 높은 부피 밀도값을 나타내었으나 시편의 표면과 내부의 부피 밀도 차이값은 컸다.

• Journal of Pharmaceutical Investigation
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• 제28권4호
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• pp.283-288
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• 1998

Lovastatin, one of the potent cholesterol-lowering agents, is an inactive lactone prodrug which is metabolized to its active open acid, lovastatin acid (LVA). Bioequivalence study of two lovastatin preparations, the test drug ($Mevacor^{\circledR}$: Chungwae Pharmaceutical Co., Ltd.) and the reference drug ($Lovaload^{\circledR}$: Chong Kun Dang Pharmaceutical Co., Ltd.), was conducted according to the guidelines of Korea Food and Drug Administration (KFDA). Fourteen healthy male volunteers, $23.9{\pm}3.9$ years old and $67.6{\pm}8.0$ kg of body weight in average, were divided randomly into two groups and administered the drug orally at the dose of 160 mg as lovastatin in a $2{\times}2$ crossover study. Plasma concentrations of lovastatin acid were analysed by HPLC method for 12 hr after administration. The extent of bioavailability was obtained from the plasma concentration-time profiles of total lovastatin acid after alkaline hydrolysis of the plasma samples. By alkaline hydrolysis, trace amounts of unmetabolized lovastatin were converted to lovastatin acid. The $AUC_{0-12hr}$ was calculated by the linear trapezoidal rule method. The $C_{max}$ and $T_{max}$ were compiled directly from the plasma drug concentration-time data. Student's t-test indicated no significant differences between the formulations in these parameters. Analysis of variance (ANOVA) revealed that there were no differences in AUC, $C_{max}$, and $T_{max}$ between the formulations. The apparent differences between the formulations were far less than 20% (e.g., 7.07, 5.77 and 1.18% for AUC, $C_{max}$, and $T_{max}$, respectively). Minimum detectable differences(%) between the formulations at ${\alpha}=0.05$ and $1-{\beta}=0.8$ were less than 20% (e.g., 17.2, 15.1, and 15.9% for AUC, Cmax, and Tmax, respectively). The 90% confidence intervals for these parameters were also within ${\pm}20%$ (e.g.. $-5.20{\sim}19.3$, $-5.00{\sim}16.5$, and $-10.2{\sim}12.5%$ for AUC, $C_{max}$, and $T_{max}$, respectively). These results satisfied the bioequivalence criteria of KFDA guidelines, indicating that the two formulations of lovastatin were bioequivalent.

• Journal of Pharmaceutical Investigation
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• 제30권1호
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• pp.55-59
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• 2000

Bioequivalence of two cisapride tablets, test drug ($Cisple^{\circledR}$ tablet: Hanmi Pharm Co., Ltd.) and reference drug ($Prepulsid^{\circledR}$ tablet: Janssen Pharm. Co., Ltd.), was evaluated according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty two healthy male volunteers were divided randomly into two groups and administered the drug orally at the dose of 10 mg as cisapride in a $2{\times}2$ crossover study. There was a week washout period between administrations. Blood samples were taken at predetermined time intervals for 36 hr and the plasma concentration of cisapride was determined by a HPLC method. $AUC_{0-36hr}$ (area under the plasma concentration-time curve from time zero to 36 hr), $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were estimated from the plasma drug concentration-time data. Analysis of variance (ANOVA) revealed no difference in $AUC_{0-36hr},\;C_{max}\;and\;T_{max}$ between two products. The apparent differences of these parameters between two products were less than 20% (i.e., 5.38, 6.17 and 0.00% for $AUC_{0-36hr},\;C_{max}\;and\;T_{max},$ respectively). The powers $(1-\beta)$ for $AUC_{0-36hr},\;C_{max}\;and\;T_{max}$ were over 0.9. Minimal detectable differences $(\Delta)$ at ${\alpha}=0.05,\;1-{\beta}=0.8$ were less than 20% (i.e. 17.67, 14.84 and 19.72% for $AUC_{0-36hr},\;C_{max}\;and\;T_{max},$ respectively). The 90% confidence intervals $(\delta)$ for these parameters were also within ${\pm}20%$ $(i.e.\;-4.97\;{\le}{\delta}{\le}\;15.73,\;-2.53{\le}{\delta}{\le}\;14.86\;and\;-11.55{\le}{\delta}{\le}\;11.55$ for $AUC_{0-36hr},\;C_{max}\;and\;T_{max},$ respectively). These results satisfied the criteria of KFDA guidelines for bioequivalence, indicating the two tablets of cisapride were bioequivalent.

• Journal of Pharmaceutical Investigation
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• 제29권3호
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• pp.241-245
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• 1999

Bioequivalence study of two cefpodoxime preparations, the test drug ($Banan^{\circledR}$: Hanil Pharmaceutical Co., Ltd.) and the reference drug ($Podox^{\circledR}$: Chong Kun Dang Pharmaceutical Co., Ltd.), was conducted according to the guidelines of Korea Food and Drug Administration (KFDA). Sixteen healthy male volunteers, $23.8{\pm}2.13$ years old and $63.34{\pm}4.84kg$ of body weight in average, were divided randomly into two groups and administered the drug orally at the dose of 200 mg as cefpodoxime proxetil in a $2{\times}2$ crossover study. Plasma concentrations of cefpodoxime were analysed by HPLC method for 12 hr after administration. The $AUC_{0-12hr}$ was calculated by the linear trapezoidal rule method. The $C_{max}$, and $T_{max}$ were compiled directly from the plasma drug concentration-time data. Student's t-test indicated no significant differences between the formulations in these parameters. Analysis of variance (ANOVA) revealed that there were no differences in AUC, $C_{max}$, and $T_{max}$ between the formulations. The apparent differences between the formulations were far less than 20% (e.g., 4.31, 1.99 and 4.30% for AUC, $C_{max}$, and $T_{max}$, respectively). Minimum detectable differences (%) between the formulations at ${\alpha}=\;0.05$ and $1-{\beta}=\;0.8$ were less than 20% (e.g., 13.89, 13.88, and 16.97% for AUC, $C_{max}$, and $T_{max}$, respectively). The 90% confidence intervals for these parameters were also within ${\times}20%$ (e.g., $-5,58{\sim}14.20$, $-7.89{\sim}11.88$, and $-7.78{\sim}16.38%$ for AUC, $C_{max}$, and $T_{max}$, respectively). These results satisfied the bioequivalence criteria of KFDA guidelines, indicating that the two formulations of cefpodoxime were bioequivalent.

• 한국콘텐츠학회논문지
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• 제22권2호
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• pp.390-399
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• 2022

본 연구는 간호대학생의 스트레스와 학업열의 및 극복력의 정도와 그 관계를 확인하고, 스트레스와 학업열의가 극복력에 영향을 미치는 요인을 파악하기 위한 서술적 조사연구이다. 연구대상자는 G시 1개 대학 간호대학생 192명이었고, 자료수집기간은 2019년 12월 23일에서 26일까지이었다. 자료분석은 SPSS 22.0 program으로 기술통계, t-test, ANOVA, Sheffé test, Pearson's correlation coefficients, 다중회귀분석으로 실시하였다. 간호대학생의 극복력은 제 특성에서 성별, 학년, 대인관계, 지원동기, 전공만족도, 학점평균 평점에 따라 유의한 차이가 있었고, 극복력과 학업열의는 정상관관계, 스트레스와는 역상관관계로 나타났다. 다중회귀모형분석에서는 학업열의가 가장 영향을 미치는 요인으로 나타났고, 주관적 건강상태 중 나쁨, 여성, 3학년 순으로 영향을 미치는 것으로 나타났으며, 모형의 설명력은 33.0%이었다. 결론적으로 간호대학생의 극복력을 강화시키기 위해 정기수업시간에서부터 내재적 동기부여를 통한 학습이 권장되는 지지적인 분위기 조성과 학업에 대한 긍정적인 생각과 성취감을 가질 수 있는 다양한 학업열의 향상 교육프로그램이 제공되어야 할 것으로 생각된다. 또한, 학업열의를 향상시킬 수 있는 PBL 등 교수법 활용을 통하여 극복력을 강화하여야 할 것으로 생각된다.

• 무역학회지
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• 제48권1호
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• pp.127-163
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• 2023

본문에서는 실증분석 부분을 두 시기로 나누어 COVID-19 전후에 해운지수 간의 변동성 파급효과 차이를 비교 분석하고자 하였다. 코로나19 전후에 해운지수 간의 평균 파급효과 및 지수 관계를 비교하기 위해 VAR 모델에 구축된 공적분 분석과 Granger 인과관계 테스트를 활용하였다. 또한, 본 연구에서는 해운지수가 단기적으로 자신의 충격에 대한 반응과 한 지수가 다른 지수에 대한 충격을어떻게 반영하는지 밝히기 위해서 충격반응함수 및 예측 오차 분산분해를 활용하였다. COVID-19 전염병 이전에는 BDI 해운지수가 CCFI 해운지수에 미치는 관계가 존재하지만 COVID-19 이후에는 BDI지수와 CCFI지수 사이에 뚜렷한 lead-lag 관계가 없다는 것으로 나타났다. COVID-19 전염병 이전에는 BDI지수는 SCFI지수의 변화를 설명하고 있고, 코로나19 확산 이후에는 SCFI 지수가 BDI 지수를 앞서고 있다는 것을 보여주고 있다. 또한 VAR-BEKK-GARCH 모델을 활용하여 COVID-19 전후 벌크 화물 해운시장 및 컨테이너 해운시장 간의 변동성 파급효과를 분석하였을 때 코로나19 이전의 BDI지수는 CCFI지수와 SCFI 지수에 대한 단발성 변동성 파급효과를 보였고 COVID-19 이후에도 BDI 지수의 변동성이 CCFI 지수에 여전히 영향을 미친다는 것을 보여준다. 하지만 코로나19 확산 이후에는 BDI지수와 SCFI지수 간의 변동성 파급 관계가 존재하지 않는 것으로 나타났다.

• Journal of Preventive Medicine and Public Health
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• 제9권1호
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• pp.11-24
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• 1976

This study was a part of large scale of a prospective study on attitudes of professional students in medicine, nursing and teaching toward population related issues in Korea. The study was first conducted in May 1974 and then in May 1975 for the 1974 class cohot using a questionaire consisted of attitude scales and other items developed by Lee. The purpose of stuay was twohold, namely, to determine the difference in students among specializations on one hand and between the first and second years in the 1974 class cohot regarding tile subject matter. A one-way analysis of variance was used for attitude scale, and absolute and relative frequency were computed for the analysis of non-attitude scale items by employing Fishers' Ratio and Duncan's multiple range test at 5% level and chi square test at 5% level as significance tests. The hypothesis 'students in health profession are more likely to have positive attitudes toward population related issues progressively as class year advances than students in teaching profession' was tested and the following results were obtained: 1) Nursing students were more likely to display favarable attitudes toward family planning than medical or teaching students although the class cohot showed slightly negative improvement in the second year. Medical and teaching students apperaed to have slightly improved attitudes in the second year. 2) Respondents in general perceived national family planning program as a means of population control and this tendency was more true among nursing students as the class year advances than two other professional groups of students. Students in teaching profession appeared to perceive it more as a means to improve individual family welfare while health students were likely to see as to improve maternal and child health. This tendency was progressively improved as the class year advanced. 3) The majority of students regardless of their respective specializations believed that family planning program should be directed toward the improvement of individual family welfare. No progressive changes in the class cohot were observed. 4) About the plan to use contraceptives in future, no singnificant differences were observes among different specializations nor in different class years. However, the majority was confirmed to have a plan to use contracepives in future. An increasing proportion of the undecided category was observed, as class year advanced among health students. 5) Students in health profession were found to be more favorable about 'more leisure opportunities' as motive for limiting number of children whereas education students indicated the reasons as 'facilitate ambitions' and 'economic base' The progressive changes toward positive direction in both groups were observed as the class years advanced. 6) Attitudes toward induced abortions of the health students were observed to be positively related to class years while an inverse relationship was found in teaching students who showed much less favor in the subject matter than health students. This phenomenon may be due to the different exposure to learning environments unique to respective specializations. 7) Health students were found to have more favorable attitudes toward population education in general than the teaching students. The teaching students appeared to have changed more to the negative direction when they became the second year while no such development was observed in health students. The teaching students seemed to hold a very conservative position with regard to sex education in schools. 8) About the equality of sexes, the nursing group was found to be most favorable while the reverse was true in the teaching group. A change in the negative direction as the class year advanced was found in the teaching group. 9) About questions related to fertility values-the 10 percent of respondents regardless of specialization indicated that they would maintain their single status in future, however no change was observed in the second year. The desired number of children was found to be two by the majority of students in nursing, medicine and teaching in order of high proportion. No changes in a different class year were observed. The childless marriage was seen by nursing students as a problem more than other students, but a slight change in positive direction was found when the nursing students became the second year. In summing, as data supported in the above, students in health profession demonstrated more favorable attitudes toward population related issues than the teaching students and this tendency became more apparent in the second year. It was noticed that health students were more conscious about the health aspect of population and family planning program while the teaching students gave more attention to the socioeconomic aspect. The sex variable seemed to have operated in the item related to the equality of sexes. In conclusion, as data presented in the above, the hypothesis of this study was accepted except in the few items. It should be noted that the limitation of this study is the short duration of the observation in measuring the possible attitude changes. It should include curriculum analysis for the respective specializations in order to indentify the area of curriculum impact on students in future study.