다공판탑을 이용한 산화질소의 흡수

김윤근 한양대학교 1981 국내석사

CF(2ⁿ)기반 타원곡선 암호 라이브러리 개발 및 디지털 서명에의 적응

김윤근 동서대학교 2002 국내석사

본 논문에서는 스마트 카드상에 타원곡선 암호시스템을 구현하기 위한 사전 연구로서 자바언어로 PC에서 GF(2ⁿ)기반의 타원곡선 암호 시스템을 구현하고 이를 ECDSA 디지털 서명에 적용하였다. 타원곡선 연산의 기반이 되는 필드 연산은 다항식 기반의 GF(2ⁿ) 필드를 채택하여, GF(2ⁿ)상에서 곱셈 연산은 recursive subdivision method를 사용하였고 역원 연산은 extended Euclidean 알고리듬의 변형을 사용하였다. 그리고 다항식 모듈러 연산은 3개의 항을 갖는 다항식(trinomial)을 사용하는 알고리듬을 구현하였다. 다항식 기반의 타원곡선에서의 포인터 덧셈과 2배 연산(doubling)은 Schroeppel 알고리듬을 구현하였다. 스칼라 곱셈은 affine 좌표축에서는 signedm-ary 방식이 가장 빠른 것으로 알려져 있으나, 이 방식은 사전 계산을 위한 메모리를 요구하므로 동작환경이 메모리가 제한되는 스마트 카드인 점을 고려하여 binary-NAF방식을 사용하였다. 상기 개발된 모듈을 사용하여 ECDSA에 적용하여 PC에서 시뮬레이션 해봄으로써 개발된 라이브러리의 활용 가능성을 확인하였다. In this paper, we developed an elliptic curve cryptographic system and applied it to ECDSA digital signature. As the pre-research to develop the elliptic curve cryptographic system on smart card, the cryptographic system was implemented with Java language. For the field operations on which the elliptic curve computations are performed, we adapted the GF(2ⁿ) based on polynomial basis. Recursive subdivision method was adapted for the multiplication over GF(2ⁿ) and the modified extended Euclidean algorithm was adapted for the elliptic curve point addition and doubling. Even thought the signed m-ary method has been known as the fastest scalar multiplication algorithm in the affine coordinates, it requires the memory capacity for pre-computation. Considering smart card's memory capacity constraint, we used binary-NAF method for the point multiplication. The developed cryptosystem module was applied to the ECDSA. Through the simulation on PC, we confirmed that the developed cryptosystem can be applicable to the construction of smart card cryptosystem.

혼화재 첨가에 의한 타일용 모르터의 접착강도 개선에 관한 실험적 연구

김윤근 경상대학교 산업대학원 2007 국내석사

Tile is an excellent architectural material for finishing and external use, with strong resistance to water, fire and detriment, while having decorative value. However, tiles have many weaknesses: when its bonding to the surface weakens, tiles fall off and may harm pedestrians; missing tiles degrade the appearance of a building, and lowers its value. Numerous factors affect bonding strength of a tile such as surface material, adhesive, property of a tile and construction methods; thus, to effectively improve bonding performance, it is important to identify critical factors and manage them. Polymer has excellent flexural strength, tensile strength and stretching capacity, has minimal drying shrinkage; also, with increased flexibility, the ratio of water to cement can be reduced to achieve same performance. Moreover, it improves water-holding capacity, and has excellent water-proof and water-tight capacity. Durability is also enhanced. Therefore, methods to mix various polymer are explored to improve bonding property of mortar to fix tiles. The research carries out a comparative analysis of strength properties for tile-use mortar and admixture mortar for compressive method, which is the most frequently used method to bond external tiles, and offers suggestions. First, literature data on polymer cement mortar and bonding strength of tiles are collected, reviewed, and analyzed so as to establish a plan and methodology for an experiment. Through preliminary testing, water-cement ratio is set to achieve cement-fine aggregate ratio of 1:2, and the flow value at 180±10㎜. Instead of traditional tile cement, mortar mixed with river sand and portland cement was used for the experiment. 4 kinds of admixture - EVA, PAE, SBR, improved SBR - were tested. To compare properties of mortar, flow, compressive and tensile strength, flexural strength, bonding strength were measured due to KS standards. To test compressive, tensile, and flexural strength, the standard specimen was cured .... for one day after taking out of the mold, then cured in water at temperature of 20±2℃ throughout the curing period. To test bonding strength, specimen was cured ..... Strength was measured at day 3, 7 and 28. The research carries out a comparative analysis of strength properties for tile-use mortar and admixture mortar for compressive method. As a result, this study came to the following conclusions: 1) Test for bonding strength showed that the increase of polymer admixture improved the strength. Compared to 28 day plain mortar, mixing 5% of polymer increased strength by 1.57~2.51 times; and 10% by 2.27~2.78 times. SBR-M showed the best performance by increasing the strength by 2.51 times and 2.78 times at mixing ratio of 5% and 10% respectively. Compared to other polymer mixed mortar, SBR-M showed increased bonding strength by 1.6 times at 5%, revealing its outstanding performance. 2) Meanwhile, test for compressive strength showed that the strength weakened with increasing ratio of polymer admixture. Compared to 28 day-cured plain mortar, the strength weakened by 0.91~0.85 times at 5% of polymer mixing, and 0.85~0.78 times at 10%. 3) As for tensile strength, the strength improved with increasing ratio of polymer admixture except for EVA. Compared to 28 day plain mortar, the strength increased by 0.98~1.06 times at 5% of polymer mixing, and 0.92~1.19 times at 10%. 4) Flexural strength improved with increasing ratio of polymer admixture. Compared to 28-day plain mortar, the strength increased by 1.06~1.14 times at 5% of polymer mixing, and 1.1~1.2 times at 10%. 5) Test for flow led to the following result: with the increasing amount of solid polymer, better workability was achieved at lower water-to -cement ratio. Compared to plain mortar, the water-to-cement ratio fell by 0.95~0.92 times at 5% of polymer mixing, and 0.91~0.84 times at 10%. It can be noted that the bonding strength of polymer mixed mortar is inverse proportionate to compressive strength, and proportionate to tensile strength. SBR-M and SBR were identified as having the best compressive, tensile, and bonding strength among 4 kinds. As to the ratio of polymer admixture, 10% showed higher compressive strength than 5% by only 1.1%, and thus to improve bonding strength, it is considered plausible to apply mortar with 10% of polymer admixture.

鷄血藤 추출물인 isoliquiritigenin의 자궁내막암세포 증식억제 및 세포자멸사 유도효과에 대한 기전연구

김윤근 대구한의대학교 2007 국내박사

Purpose : Endometrial Cancer is the 3rd most common gynecologic malignancies in Korea. Despite the fact that endometrial cancer is so common, innovative research has traditionally been lacking. Isoliqiritigenin (ISL) is a chalcone flavonoid, present in licorice, shallot and bean sprouts, has cancer-preventing properties and often used in Oriental medicine. ISL is one of components in Spatholobus subrectus Dunn in the literature. In the present study we used ISL to determine its effect on cell proliferation and cell cycle progression in human endometrial cancer cell line, HEC1-A. Methods : Endometrial cancer cells (HEC-1-A) were treated with ISL. Cell viability analysis was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazoliumbromide (MTS) assay and Flow cytometry was performed to ascertain the effects ISL. Expression of cell cycle related proteins and apoptosis related proteins were evaluated by Western blot analysis. Results : Cell viability was significantly influenced by ISL treatment in a dose-dependent manner. Flow cytometry results showed that ISL induced Sub G1 and G2/M arrest. To reiterate this observation, DNA fragmentation assay was carried out and apoptosis was detected. Activation of caspase-3 and caspase-8, down-regulation of Bcl-2, with concomitant increase in Bax and FAS was observed. ISL treatment of endometrial cancer cells resulted in a concentration-dependent cell death induced via the FAS receptor-apoptosis cascade mechanism. Conclusions : These results suggest that ISL treatment in endometrial cancer cells leads to growth inhibition and that this inhibition is mediated at least in part by apoptosis via the FAS death receptor induced caspase-8 cascade pathway. These results suggest that ISL will be a promising agent for use in chemopreventive or therapeutics against human uterine endometrial cancer. 1. 목적 본 연구는 계혈등의 주요 성분중 하나인 isoliquiritigenin (ISL)을 체외배양한 자궁내막암세포에 처리 한 후 증식억제 효과를 조사하고 세포주기 분석과 DNA fragmentation 분석을 통하여 세포자멸사와의 연관성을 규명하고 그 기전을 밝히고자 세포주기 및 세포자멸사 관련유전자의 발현에 대하여 조사하였다. 2. 연구방법 자궁내막암 세포를 일차배양한 후 ISL을 농도별로 처리하고 MTS assay로 증식억제효과를 관찰하고 FACS 분석 및 DNA fragmentation 분석을 통하여 세포자멸사와의 관계를 조사하였으며, caspase 활성을 보기 위해 activity 실험을 하였으며, Western blot analysis 방법으로 세포주기 및 세포자멸사 관련 유전자의 발현도를 측정하였다. 3. 결과 ISL이 처리된 자궁내막암 세포는 농도의존적으로 증식억제 효과가 증가하였으며, 이러한 증식억제 효과는 FACS 분석 및 DNA fragmentation 분석을 통하여 necrosis에 의한 것이 아니라 세포자멸사에 의한 것임을 확인하였다. 이러한 기전에 대하여 세포주기 관련 유전자 발현도를 측정한 결과 p21, p27은 ISL의 처리 농도에 비례하여 발현도가 증가하였으며, FAS와 Bax의 증가로 caspase-8의 활성을 확인하였다. Caspase pathway를 조사한 결과 caspase-8, caspase-3의 활성과 PARP 단백의 발현은 감소하였다. 4. 결론 결론적으로 ISL은 자궁내막암 세포의 증식억제 효과가 있으며 이는 세포주기상에서 sub G1 phase arrest를 일으켜 세포자멸사를 유도하며 여기에는 p21과 p27의 세포주기 관련 유전자가 관계되어 있음을 알 수 있었다. 이 외에 세포자멸사가 일어나는 것과 관련된 유전자의 발현에서 FAS와 Bax의 증가로 caspase-8의 활성과 종국에는 caspase-3의 활성에 의한 세포자멸사를 유도하고, Bcl-2 유전자는 세포자멸사를 방해하는 유전자로 감소되어 있는 것을 알 수 있었다. 이러한 결과는 ISL이 세포주기와 세포자멸사에 관련된 유전자들의 발현에 영향을 미침으로써 자궁내막암세포의 증식을 억제하며, 종국에서는 세포자멸사에 이르게 한다 하겠다. 그러므로 본 실험은 ISL이 자궁내막암의 약물적인 치료에 있어 향후 가치가 있는 기초 자료를 제공해 준다고 생각된다.

キタコブシ Magnolia kobus DC. var. borealis Sarg. の抽出成分に關する硏究

김윤근 北海道大學 1996 해외박사

일본산 목련인 키타코부시 (Magnolia Kobus DC. var. borealis Sarg. )는 일 본 혼슈북부 및 북해도에 많이 자생하는 대형의 교목(橋木)이며, 목련속 수 목의 일부는 옛부터 한약의 신이(辛夷)와 후박(厚朴)의 원료로 이용되어 왔다 . 최근에는 천연물의 기능과 그 이용방법이 활발히 연구되고 있어, 이들의 성분을 얻을 수 있는 자원의 깊이 잇는 조사와 미지성분의 성상 (性狀)을 파 악하는 연구가 중요한 과제가 되고 있다. 이런 관점에서 지금까지 정밀히 조 사되어 있지 않은 키타코부시를 대상으로 잎, 목부, 수피 그리고 꽃봉우리의 추출성분을 조사하여 그 성상을 밝히는 것을 목적으로 본 연구가 수행되었고, 잎의 리그난의 계절변동, 항산회성 및 생물활성도 부가하여 밝혔다. 키타코부시의 잎, 목부, 수피 그리고 꽃봉우리의 에탄올 추출성분을 검색한 결과, 각 부위에서 단리한 리그난은 Furofuran형의 kobusin, aschantin, eude smin, magnolin, yangambin, medioresinol, fargesin, phillygenin, epimagno lin, (-)syringaresinol의 10종과 Tetrahydrofuran형의 kobusinol A, Kobusin ol B와 magnostellin A의 3종을 단리하였다. 잎에서 단리한 kobusinol A와 kobusinol B는 신규화합물이고, 목부의 (-)syringaresinol은 천연물로서 단리 된 예가 많지 않다. 각 부위에서 단리한 리그난들은 대부분 유리의 페놀성 수산기, methylenedioxy기, methoxyl기로 치환되어 있으며, 이 수목의 특징이 였다. 리그난의 계절변동을 HPLC를 이용하여 함유량을 검색한 결과, 잎의 주 요성분은 epimagnolin, magnolin이고, 목부는 (-)syringaresinol이였다. 수 피는 yangambin과 magnolin, 꽃봉오리는 magnolin과 yangambin이였다. 한방약의 신이(辛夷)는 M. fargesii Cheng. 의 꽃봉우리를 쓰고 있지만, 여기 에 함유된 리그난은 키타코부시의 경우와 같이 methoxyl기 또는 methylenedio xy기로서 치환되어 있는 리그난이 많다. 단리 리그난의 항산화성과 생물활성 을 검토한 결과, 항산화성은 유리의 수산기를 갖는 것이 활성을 보였으며, 그 치환의 유무가 항산화성에 기여하였다. 생물활성에서 가장 강한 억제효과를 갖고 있는 것은 (-)syringaresinol이였고, 타의 것도 모두 유리의 페놀성 수 산기를 갖고 있었다. The purpose of this study is to examine the role of networks in the transition from college to the world of work. It draws on the network theory of employment. Data on 1012 baccalaureate graduates at a large midwestern research university in May, 1990 were used. The data were drawn from a graduation survey and combined with University files and ACT Student Profile data. From these primary data, two subdata,sets were constructed - network and employment samples. Analyses of the data revealed the following major results regarding baccalaureate graduates' job search and initial employment. Job search 'variables overall contributed to initial career success. Earlier search and use of proper methods were important for a smooth transition from college to employment. Networking was one of the popular job search methods, and its effectiveness ranked in the middle of the various techniques. However, the unique contribution of informal methods to initial employment success was not statistically significant. Heavy use of informal methods by students with low employability partially decreased their productivity. No significant interaction terms between networking and personal background variables were found. The "strength of weak ties" hypothesis was not supported. The advantage of weak ties relative to strong ties in finding a good job observed at the bivariate level was. significantly diminished net of control variables. Recruitment methods were related to organizational characteristics in various ways. Larger firms used placement office and written procedures more and informal means less frequently than smaller firms. Service industry firms used direct hiring methods commonly, relative to manufacturing firms. ~Public organizations used written procedures and personal contacts (weak ties) more frequently and utilized more methods for hiring baccalaureate employees than private organizations. To obtain a better understanding of the college to work transition, we need to develop standardized instruments to measure networks and other job search variables, and to examine the dynamic nature of job search and organizational hiring practices.

전자파 차폐를 위한 도전성 분말의 제조 및 특성

김윤근 安東大學校 大學院 2006 국내석사

동적 신뢰성 모형에 의한 경사제 피복재의 안전성 해석

김윤근 강원대학교 2002 국내석사

구상나무 抽出物의 生理活性에 關한 硏究

김윤근 慶尙大學校 1998 국내박사

청각장애학교 미술과 교육과정 운영에 대한 질적 연구

김윤근 대구대학교 2003 국내석사

The Art is children’s way of expressing and telling stories and is a way of communicating their unique view of the world around them. Their activities of the Art is personal narratives which help them to externalize or make tangible their emotions, experiences, and problems. Even though the deaf children would be limited to express their feeling with spoken andor written materials, the Art is fantastic activities which the deaf children express and communicate through their language, in other words, the language of the Art. The purpose of this study was to approach with a qualitative research on curriculum management of the Art education for the schools of the deaf in South Korea. Four Art teachers and nine deaf students in three schools for the deaf and were participated for this study. Individual interview procedures were utilized for to analyze the conditions and future directions for the Art education in schools for the deaf. The results of this study were divided into three parts. First, the results of the teachers’ interview were that: (a) the Art curriculum was managed with vacational schools; (b) the books of the Art was not concerned with the characteristics of the deaf students; (c) educational methods in the Art was not related with the deaf children’s unique needs such as communication modes; and (d) equipments and materials to teach the Art were not sufficient. Second, the results of the students’ interview were that: (a) the Art education was interesting subject during elementary levels, however, the courses were boring during secondary levels because of teaching of the simple skills; (b) the deaf students’ needs and interests were not concerned in the Art classes; (c) teaching with computer to teach design andor graphic was not supported; and (d) the teachers for the deaf were concentrated to teach simple skills, not related with entering College or University. Third, the results of the future direction were that: (a) the Art curriculums and books were developed for the deaf students; (b) creative education in the Art education was considered, not simple skills; (c) various education materials such as CD, video, ICT, and photoshop were utilized for the Art classes: and (d) the teachers for the deaf have to endeavor to get satisfied communication skills with deaf students.

아동의 심리적 가정환경이 자아개념 형성에 미치는 영향

김윤근 관동대학교 교육대학원 2009 국내석사

본 연구는 초등학교 4, 6학년 아동들을 대상으로 초등학생 아동들 스스로가 지각한 가정환경이 자아개념 형성에 미치는 영향을 밝혀 봄으로써 아동의 건전한 자아개념 발달을 위한 기초적이고 실증적인 자료를 마련하고자 하는 목적이 있다. 이러한 연구의 목적과 관련하여 다음과 같은 연구문제를 설정하였다. 첫째, 심리적 가정환경과 아동의 자아개념은 성별로 어떠한 차이가 있는가? 둘째, 심리적 가정환경과 아동의 자아개념은 부모맞벌이 여부에 따라 어떠한 차이가 있는가? 셋째, 심리적 가정환경은 아동의 자아개념 형성과 어떠한 상관관계가 있는가? 이상의 연구 문제를 해결하기 위하여 본 연구는 강원도 삼척시에 소재한 초등학교 4, 6학년 아동 남, 여 각 100명씩을 대상으로 하여 가정환경 진단 검사와 자아개념 검사를 실시하여 연구대상으로 삼아, 총 400부의 검사지를 배포하여 400부를 회수하여 수집된 자료를 SPSS/Win. (Ver.11.0) 프로그램에 의해 처리를 하였으며, 각 배경 요인별로 평균값(M)과 표준편차(SD)를 토대로 t검증을 실시하였고, 단순상관계수(r) 추출을 통한 상관관계 분석을 실시하였다.