Phase Transition Behaviors of Chiral Azobenzene Dendrimer

김대윤,이상아,정광운 한국고분자학회 2014 한국고분자학회 학술대회 연구논문 초록집 Vol.2014 No.10

Lamello-Columnar Mesophase of a Tetrathiafulvalene Molecule

김대윤,이명훈,정광운 한국공업화학회 2012 한국공업화학회 연구논문 초록집 Vol.2012 No.1

體位變更이 Furosemide 利尿效果에 미치는 影響

金大潤 충남대학교 의과대학 지역사회의학연구소 1975 충남의대잡지 Vol.2 No.1

Variations of hematocrit ratio, urine volume and urinary sodium and potassium excretion have been studied after a water load with a two hour period of recumbency or upright position followed by furosemide infusion in normal healthy volunteers with previous diuretic therapy or without any pretreatment. On the morning of the study, subjects of each group were instructed to take a usual breakfast allowed. They were ambulatory until arrival at the laboratory early morning and at 11:00 a.m., at which time the bladder emptied. The subjects were given 500m1 of water and were recumbent or upright for the remainder of the experiment. After 2hr, urine specimens were taken and then, 40 mg of furosemide was given intravenously, and urine specimens were obtained at 30, 60, 90 and 120 minutes. Urinary sodium and potassium concentrations were determined by means of a flame photometer, and urinary sodium and potassium excretion along with potassium to sodium ratio were calculated. From above data, effects of postural change and previous diuretic therapy on diuretic patterns were studied. The results were as follows; 1. Urine volume after water load or furosemide infusion of upright group was significantly decreased comparing with recumbency position group. 2. Amount of sodium excretion of upright group showed lower value than that of recumbency. 3. Potassium excretion of upright group and recumbency group didn't show any difference, however K/Na excretion ratio of upright group was higher because of decrease of sodium excretion. 4. Diuretic effects of furosemide on urine volume, sodium and potassium excretion of subjects with previous diuretic therapy were decreased than that of control subjects. 5. Significant decrease of potassium excretion was showed in upright subject with previous diuretic therapy. From the above results, author found postural change influenced significantly the diuretic patterns.

산질화 표면에서 액적의 증발열전달 특성

김대윤,이성혁 한국분무공학회 2016 한국액체미립화학회지 Vol.21 No.1

The present study aims to experimentally investigate the evaporative heat transfer characteristics of Oxi-nitriding SPCC surface. Moreover, the heat transfer coefficient was examined with respect to surface temperature during droplet evaporation. In fact, the nitriding surface showed significant enhancement for anticorrosion performance compared to bare SPCC surface but the thermal resistance also increased due to the formation of compound layer. From the experimental results, the evaporative behavior of sessile droplet on nitriding surface showed similar tendency with the bare surface. Total evaporation time of sessile droplet on the nitriding surface was delayed less than 5%. The difference in heat transfer coefficient increased with the surface temperature, and the maximum difference was estimated to be around 11% at 80oC surface. Thus, this nitriding surface treatment method could be useful for seawater heat exchanger industries.

Amphiphilic Tetrathiafulvalene Molecule

김대윤,이명훈,정광운 한국공업화학회 2012 한국공업화학회 연구논문 초록집 Vol.2012 No.1

Clor and Shape Tunable Photonic Polymer

김대윤,정광운,윤원진,이상아 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.0

농산물 소매유통환경 변화에 따른 산지유통조직 개선방안에 관한 연구 : 조직화 · 규모화 · 전문화를 중심으로

김대윤 한국유통과학회 2011 한국유통과학회 학술대회 논문집 Vol.2011 No.-

1996년도의 유통시장개방을 계기로 소매유통 환경이 급변하기 시작하였으며, 이러한 소매유통 환경변화에 대한 대응력을 강화하기 위해 조직화를 통한 규모화가 산지의 중요한 과제로 대두되고 있다. 이에 산지에서는 여건변화에 대응하기 위하여 소규모 개별농가가 조직화를 통해 전문화·대규모화 되어 가고 있고, 품목별·지역별로 특화되어 가는 양상을 보이고 있다. 하지만 소비지 시장에 대한 경쟁력 강화라는 관점에서는 여전히 문제점을 보이고 있는 것이 사실이다. 이러한 문제점의 가장 대표적인 경우가 시장대응상의 산지유통조직의 조직화·규모화 문제이다. 본 연구에서는 선행연구들을 통한 농산물 유통환경 변화에 따른 산지 조직화 배경 및 필요성, 국내 산지유통조직의 현황 및 문제점, 국내·외 산지유통조직 우수사례를 살펴보고, 조직화·규모화를 중심으로 향후 산지유통조직 경쟁력 제고방안을 위한 개선방안에 대해 제시하였다. 농산물 소매유통환경 변화에 따라 산지유통조직의 경쟁력을 제고 하기 위한 개선방안으로는 원물수집체계 다양화를 통한 가동률 향상 및 조직화 강화, 전문화된 품목의 광역연합마케팅 추구를 통한 규모화 실현, 국외 산지유통조직 우수사례인 프랑스“브레따뉴 청과물 경제위원회”와 같은 관리 운영조직 설치 및 운영, 국내에 적합한 산지유통조직모델 개발을 위한 지원체계 확립 등을 제시하였다. 특히 국내 산지의 경우 산지조직화•규모화에 성공한 각종 사례분석을 통해, 조직적 규모화의 과정 속에서 생겨나는 각종 어려움과 그에 대한 극복방식 등을 일반화 시켜가는 노력이 요구된다.

Synthesis of Smart Denpol via ROMP: Interplay between Effect of Self-Assembled Hierarchical Superstructure and Photo-Responsive Mechanical Work

김대윤,정광운 한국고분자학회 2017 한국고분자학회 학술대회 연구논문 초록집 Vol.42 No.1

退溪·栗谷의 孝思想과 敬老敎育

金大奫 弘益大學校 1985 弘大論叢 Vol.17 No.1

The purpose of this study is not only to analyze the idea of filial piety of Twaege and Yulgok which had a great influnce on filial piety and education of respect for the aged during the Chosun period, but also to find out haw their educational philosophy and methods were related to [educational idea] of respect for the aged during that peried. In this study, concepts, nature, and foundations of filial piety, as well as the practice of education of the respect for the aged were mainly inguired. Particularly, the practices of educational philosophy of Twaege and Yulgok on filial piety and education of respect for the aged were analyzed. In addition to this, the practics of education of respect for the aged in school education were closely examined. Main references used for this study were Hyokyung (the Book of Filial piety), Mencius, Neneo, Twaege-munhunjip (Twaege's Writlngs), Twaege-Unhaengrok (The Record of Dialogue and Behavior of Twaege), Yulgok-chonseo (The Anale cts of Yulgok), Sunghak -Jipyo, and Hakkzo-Mobum (School standards). The findings of this study show that Twaege and Yulgok's idea of filial piety, emphasis on education of respect for the aged, and their teaching filial piety exerted a significant influence on the idea of respect for the aged. The idea of filial piety had been regarded as asbasic moral standards of virtue to bring family peace through self control, and life ethics and moral order of assuming responsibility and obligation as a member of the society. Filial piety was the Core of the Virtue, basic principle of ruling the family; basis for Controlling the self, managing the family, governing the nation, and finally attaining the world peace. There fore, the educational philosophy of filial piety and Virtue of Twaege and Yulgok and their emphasis on filial piety performed a significant role not only in forming and transfering the idea of filial piety and respect for the aged for the young generation of those times, but also in promting the idea of respect for the King as well as the general public.

Photo-responsive chiral liquid crystal for optically tunable thin film

김대윤,정광운 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.0

Recently, liquid crystals have attracted a lot of scientists and engineers owing to their anisotropic properties and self-assembly behaviors. More recently, incorporation of configurational chirality in a soft material has been reported for the changing the molecular packing symmetries. Additionally, photo-tunable properties of mesophases are intriguing field to create the functional materials. In this circumstance, we designed and synthesized the programmed liquid crystal (abbreviated as LCIA) containing both chiral isosorbide central core and light responsive azobenzene mesogen. Remote controllable phase transformation in the mesomorphic layer structures (smectic A phase) and helical superstructures (chiral nematic and blue phase) of LCIA are successfully demonstrated by tuning the wavelength of light for optically tunable thin film. **This work was mainly supported by BRL (2015042417), BK21 Plus program and Global Ph.D Fellowship program, Korea.