추황배(Pyrus pyrifolia Nakai cv. Chuhwangbae) 과피로부터 1종의 Sterol과 3종의 배당체 화합물의 단리·동정

이유건(Yu Geon Lee1),조정용(Jeong-Yong Cho),이현주(Hyun Joo Lee),이용현(Yong Hyun Lee),이상현(Sang-Hyun Lee),한태호(Tae-Ho Han),김월수(Wol-Soo Kim),박근형(Keun-Hyung Park),문제학(Jae-Hak Moon) 한국식품과학회 2013 한국식품과학회지 Vol.45 No.5

본 연구에서는 배의 유용성 증명을 위한 일환으로 배의 화학성분을 분자수준에서 밝히고자 하였다. 이에 배 과피 MeOH 추출물을 용매분획하여 얻은 EtOAc-산성 분획과 EtOAc-중성분획을 대상으로 Sephadex LH-20, silica gel, 그리고 ODS colmn chromatography와 HPLC를 이용하여 정제 및 단리하였다. 그 결과, EtOAc-산성 분획과 EtOAc-중성 분획으로부터 각각 2종씩의 화합물을 단리하였다. 단리된 화합물 1-4는 1H- 및 13C-NMR 분석을 통하여 각각 (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (화합물 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone(piceoside, 화합물 2), β-sitosterol (화합물 3), 그리고 β-sitosteryl 3-O-β-D-glucopyranoside (화합물 4)로 동정되었다. 단리된 3종의 배당체 화합물(화합물 1, 2, 4)들은 본 연구에 의해 배로부터 처음 동정되었으며, 화합물 3은 추황배로부터 처음 동정되었다. 본 연구결과가 배 함유 성분연구는 물론 배의 기능성 해명 연구에도 추후 중요한 기초자료로 활용되길 기대한다. We isolated and identified antioxidants from acidic and neutral ethyl acetate fractions of the peel of pear (Pyrus pyrifolia N. cv. Chuhwangbae). We isolated 4 compounds from the methanol extract, by using 3 different types of column chromatography (Sephadex LH-20, silica gel, and octadecylsilane) and preparative HPLC. We identified the isolated compounds as (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (compound 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone (picroside, compound 2), β-sitosterol (compound 3), and β-sitosteryl 3-O-β-D-glucopyranoside (compound 4) by nuclear magnetic resonance analysis. We are the first to report the identification of compounds 1, 2, and 4 from pear.

부순모래를 사용한 고강도 콘크리트의 배합설계에 관한 연구

이봉학,김동호,홍창우,이주형 江原大學校 産業技術硏究所 2001 産業技術硏究 Vol.21 No.A

The amount used of aggregates for concrete is increasing rapidly since the mid-1980s in Korea. The natural gravels from river are already displaced with crushed stone, and use of crushed sand as a substitute of natural river sands, also, is getting increased day by day. This paper is presented for mixture of high strength concrete using crushed sands. Mixing design of concretes alee various water-cement ratios(w/c) such as 25%, 40%, 55% and different replacement radio of crushed sands to natural sands such as 0%, 20%, 40%, 60%. As a results, it has been shown that compressive strength of concretes with w/c lower than 40% and 25% is higher than 400 kgf/cm2 and 600 kgf/cm2 respectively.

鐵筋콘크리트 보의 附着擧動에 관한 硏究

이주형,이봉학,홍창우,김동호 江原大學校 産業技術硏究所 1998 産業技術硏究 Vol.18 No.-

Cracking is considered to be one of the important factors in determining the durability of reinforced concrete structures. When the bending stress exceeds the modulus of rupture of the concrete, cracking fom along the length of members. The total load is transferred across these cracks by the reinforcement, but the concrete between craks is still capable of carrying stresses due to the bond between steel and concrete. This phenomenon is called the tension stifening effect. The tension stiffening effect is affected by many variables, such as the bond stress, strength of concrete, interrocking of aggregate, type of steel, and dowel action of steel. Also, this tension stifening effect is usually quite significant in beams under service loading, and must be taken into account in the calculation of deflection and crack widths. In this study, the experiment was carried out on types of specimen, strength of concrete, and steel ratio and finite element analysis were compared in terms of load-deflection relationship, crack pattern.

敎育目標의 槪念 分析

李學周 춘천교육대학교 초등교육연구소 1981 敎育硏究 Vol.4 No.-

兩端固定 圓弧 아-치의 平面內 固有振動에 關한 硏究

이병구,황학주,이원복 연세대학교 산업기술연구소 1975 논문집 Vol.6 No.1

Numerical data have been presented for the natural frequencies and modes of vibration of fixed, uniform, circular arches vibrating in their own plane, and the effects of the rotatory inertia and shear deformation affecting the response have been analyzed. The governning differential equations were solved numerically by a combination of a Holzer-type iterative procedure and an initial value integration procedure. The Runge-Kutta fifth order integration technique was used. The method was programmed for a Cyber 73-18 computer system, and all results were obtained on this computer system. A detailed study has been made of the lowest five vibration frequencies and mode shapes for a fixed arch with an angle of opening equal to 90 degrees. The effect of slenderness ratio and the influence of the rotatory inertia and shear deformation on frequencies are presented in detail in curves.

靑少年 問題의 敎育的 一考察 : 敎育的 側面의 問題點 診斷을 中心으로 A diagnosis of problems from the perspective of education

李學柱,張起豊 울산대학교 1986 연구논문집 Vol.17 No.1

靑少年 問題는 오늘날 우리 社會의 가장 심각한 사회문제 중의 하나로 擡臺되고 있으며, 그 深刻性은 날로 더해가는 느낌이다. 特히, 청소년 범죄의 質的인 변화와 학생 범죄의 急增 추세는 우리에게 敎育力의 强化를 요청하고 있다. 따라서 本 論文은 靑少年 問題를 敎育的 側面에서 고찰한 것으로, 청소년을 바람직한 방향으로 지도하기 위한 敎育的 指針을 제공하려는데 그 目的이 있다. 이러한 目的을 성취하기 위해 청소년 관계의 先行 硏究文獻을 理論的으로 考察하고 統計 資料를 分析하였다. 結論的으로, 청소년에 대한 기성세대의 敎育的 責任이 강화되어야 하겠으며, 그들의 꿈과 理想을 펼칠 수 있는 敎育環境이 마련되고 社會全體가 敎室이라는 認識이 확산되어야 할 것이다. The youth problems are being on the rise as one of the most serious social problems of our society today, their seriousness have a feeling to become worse day by day. Especially, the qualitative change of juvenile delinquency and rapidly increasing trend of student-crime are asked us for strengthening the educational power. Therefore, this paper is to review on the youth problems from the perspective of education, aims at offering an educational guideline for instructing young boys and girls toward a desirable direction. To accomplish this purpose, this paper examined the preceeding research literatures theoretically, and analyzed statistical data. Conclusively, the educational responsibility of the older generation to our younger generation should be strengthened, the educational environment that spreads out their dream and ideal will be provided, and the recognition that the whole society is classroom should be disseminated.

意味辨別法으로 測定한 敎師像에 관한 一硏究

李恩玉,李學柱 울산대학교 1985 연구논문집 Vol.16 No.2

本 硏究는 大學生이 갖는 敎師像을 意味 辨別法으로 測定·分析하기 위하여 40쌍의 대칭되는 形容詞間項을 사용하였다. 標集은 서울과 지방에서 4개 대학을 선정, 모두 579명으로부터 資料를 募集하였고. 資料는 全體, 性別, 系列別로 平均, 標準偏差를 算出하고, t-檢證 및 要因分析 하였으며 그 結果는 다음과 같다. 1. 全體的으로 大學生이 갖는 敎師像은 肯定的이나, 그 지지정도는 多小 中立的이어서 鮮明하지 않다. 部分的으로 活動, 力能次元에서는 否定的인 경향도 나타내고 있다. 가장 肯定的인 반응을 보인 문항은 '중요하다', '自尊心이 강하다', '精神的', '깨끗하다' 등이었고, 가장 否定的인 반응을 보인 문항은 '소심하다', '보수적이다', '방어적', '고지식하다' 등이었다. 2. 大學生의 性別에 따른 敎師像은 男學生이 女學生에 비해 훨씬 强하게 肯定皓일 경향을 나타내고 있다. 이런 경향은 '순진하다', '깨끗하다', '옳다', '똑똑하다', '헌신적이다'라는문항에서 두드러지게 나타났다. 3. 大學生의 系列別에 따른 敎師像은 非師範系가 師範系 學生에 비해 다소 肯定인 경향을 나타내고 있다. 이런 경향은 '깨끗하다', '새롭다', '의욕적'이라는 문항에서 나타나고 있다. 4. 大學生이 갖는 敎師像의 栗因構造는 "進取性"과 "誠實性"이 대부분을 차지하고 있는데, 이중 진취성에는 부정적인 경향을, 성실성에는 긍정적인 경향을 나타내고 있다. 以上의 結果를 토대로 볼때, 大學生에게 비쳐진 敎師의 이미지는 全般的으로는 肯定的이나, 倫理·道德的인 側面에서는 보다 肯定的 方向에서, 活動·力能面에서는 多小 否定的일 方向에서 知覺되고 있으며, 이런 경향은 男學生이나 比師範系 學生보다는 女學生, 師範系 學生에게서 더욱 두드러지게 나타나므로, 漸增하고 있는 敎職의 女性化 추세에 비추어 現行의 師範·敎職敎育에서 이에 대한 적절한 對策 마련이 있어야 할 것이다. This study is an attempt to measure college students' image on "teacher", and to determine the factor structure of the image. This study used a semantic differential scale that was constructed with 40 bipolar adjective items. The scale was administered to 579 college students. Mean scores were computed for every adjective pair for the male group, the female group, the teacher-training course students, non-teacher-training course students and the combined group. This analysis showed a tendency that 1) the college students, generally, had positive images on "teacher". Only on 7 items, they showed negative tendencies such as "narrow-minded, " "conservative" , "defensive" , "simple-minded" etc. The most positive responses were "important", "self-respectful", "spiritual", "clean" act. 2) Significance tests for the sex difference showed that the male students had more strongly positive images on 16 items and more negative images on 1 item on teacher than the female students. That is, the male students' images on "teacher" were more incline toward "pure", "clean", "right", "clever", "self-sacrificing", and less toward "talkative". 3) Significance tests for the course difference showed that the non-teacher-training course students had more positive images on 7 items and more negative images on 2 items on teacher than the teacher-training course students. That is, the non-teacher-training course students' images on ."teacher" were more inclined toward "clean", "new", "willingly" and less toward "difficult" , "talkative". And the data were subjected to factor analysis. Using a criterion of eigenvalue greater than, 1, followed by the varimax rotation, 9 factors were selected. The common variance of 56.5% in the meaning or image of "teacher" were calculated for all these 9 factors. Items that had factor score coefficient of .10 or greater on a single factor were arbitrarilly selected to represent that factor. The 9 factors have been named "Progressiveness", "Sincerity", "Nobility", "Self-Fulfilment", "Sagacity" , "Quickness" , "Complexity" , "Faithfulness" . Among the factors, the 1st factor (Progressiveness) accounted for 25.6% of the common variance, 55% of the common variance accounted for 9 factors. This implies that "Progressiveness" dimension is the most important for assessment of the "teacher" image. But the students showed negative tendency in 1st dimension. The 2nd factor (Sincerity) accounted for 7.7% of the common variance, 14.2% of the common variance accounted for 9 factors. In 2nd dimension, the students showed positive tendency. The results imply that students have image on "teacher" who was "negative", "narrow-minded", "conservative", "defensive", "simple-minded", "weak", but "selfsacrificing", "sincere", "responsible", "clean", "believable"

인식론의 흐름과 교육(Ⅰ)

이학주 仁川敎育大學校 1986 論文集 Vol.20 No.1

'실천'의 의미와 교육

이학주 仁川敎育大學校 1987 論文集 Vol.21 No.1

哲學的 입장에서 본 初等敎育의 普遍性과 特殊性

李學周 춘천교육대학교 초등교육연구소 1981 敎育硏究 Vol.4 No.-