Rat에 있어서 ethanol투여가 체조직의 무기질 함량에 미치는 영향

이근우,이현범,Lee, Keun-woo,Lee, Hyun-beom 대한수의학회 1989 大韓獸醫學會誌 Vol.29 No.1

This study was designed in order to clarify the effect of ethanol drinking on the mineral contents on liver, kidney, muscle and hair. Forty-five rats were divided into 2 groups and a control group. The control group received tap water and the other 2 groups were given 8% and 40% ethanol as drinking source. Liver, kindney, muscle and hair samples were taken and analyzed for zinc, calcium and copper contents by atomic absorption spectrophotometric methods. The results obtained are summrized as follows; 1. The zinc content of muscle showed significant (p<0.01) decrease in both groups. 2. The calcium content of hair showed significant (p<0.1) increase in 8% ethanol group. 3. The copper contents of kidney and muscle in 8% ethanol group and liver in 40% ethanol group showed significant (p<0.1) decrease.

사료내 카드뮴 첨가가 체조직과 피모의 카드뮴, 아연, 철 및 구리함량에 미치는 영향

이근우,이현범,Lee, Keun-woo,Lee, Hyun-beom 대한수의학회 1987 大韓獸醫學會誌 Vol.27 No.2

This thesis was designed to find out whether the cadmium content of hair in living animals reflects the status of cadmium accumulation in internal organs or muscles so that this status can be used as a diagnostic method. Forty-five rats were divided into 4 experimental groups and one control group. The control group received a basal diet which contained zinc $100{\mu}g/g$, iron $80{\mu}g/g$ and copper $135{\mu}g/g$. The experimental group received experimental diets sllpplemented with 1, 10, 100 or $1,000{\mu}g/g$ cadmium as cadmium sulfate. Rats were dissected on the 28th or 56th day of experimental periods and tissues, blood and hair samples were taken, dried and burned to ash and analysed. The cadmium, iron zinc and copper concentrations were measured with an atomic absorption spectrophotometer. In addition feed efficiency and hematological changes were observed. The results obtained can be summerized as follows: A marked decrease in feed intake, weight gain and feed efficiency were observed from 1 or 2 weeks of experimental periods, which was in accordance with the dosage and periods. The cadmium contents of kidney, liver, spleen and muscle were significantly increased in all experimental rats; the accumulation was marked in kidney and liver tissues. It was shown that the cadmium contents of hair reflects the cadmium accumulation in internal organs and muscle; the higher the cadmium levels of diet and of rat tissues, the higher the cadmium content of hair. In the $100{\mu}g/g$ group of rats erythrocyte counts and. hemoglobin concentrations were decreased. A significant(p<0.01, p<0.05) increase in iron contents of kidney, liver and muscle was observed in 10, 100, $1,000{\mu}g/g$ groups of rats on the 28th day of experiment. A significant (p<0.01, p<0.05) increase in zinc contents of kidney, liver and muscle was observed in all experimental rats. On the other hand, serum zinc concentration was decreased. A significant(p<0.01) increase in copper contents in the liver was observed on the 28th day in $100{\mu}g/g$ and $1,000{\mu}g/g$ groups of rats. From these results it may be concluded that the analysis of hair for cadmium is a useful diagnostic approach for the cadmium status of internal organs and muscle in living animals.

섬유주세포에서 Dipyridamole이 활성산소종과 산화스트레스에 미치는 영향

이근우,김재우,Keun Woo Lee,Jae Woo Kim 대한안과학회 2013 대한안과학회지 Vol.54 No.3

Purpose: To investigate the effects of dipyridamole (DPD) on the production of reactive oxygen species (ROS) and oxidative stress in cultured human trabecular meshwork cells (HTMC). Methods: Antioxidant activity of DPD was determined by DPPH assay. Primarily cultured HTMC were exposed to 0, 20, and 50 μm DPD using serum-deprived media. The effect of DPD on the production of ROS was assessed with the DCHFDA assay. The effect of DPD on the t-butyl hydroperoxide (tBHP)-induced oxidative stress was assessed with resazurin assay. Results: DPD showed significant antioxidant activity. DPD significantly decreased the production of ROS (p < 0.05) and improved cellular activity significantly after treatment with t-BHP (p < 0.05). DPD did not affect the generation of nitric oxides. Conclusions: DPD suppressed the formation of ROS and possessed cytoprotective activity against the oxidative stress in HTMC.

도저용 착시 도재-금속 개면에서의 원소이동에 관한 실험적 연구

이근우,이호용,Lee, Keun-Woo,Lee, Ho-Yong 대한치과보철학회 1987 대한치과보철학회지 Vol.25 No.1

This study was undertaken to observe the elemental transition of Interface depending on different pretreatment methods, the number of filings, the kinds of porcelain powders and the various alloys in ceramo-metal restoration. The materials used in this study were Pors-on $4^{(R)}$ and Ceramco porcelain powder to compare the differences depending on the pretreatement methods and the number of firings. Ceramco porcelain powder and Vita porcelain powder were used to compare the differences of elemental transition depending on the porcelain powders. The $Parasil^{(R)},\;PGV^{(R)}$ and Pors-on $4^{(R)}$ as Pd-Ag alloy were used to compare the difference of elemental transition depending on the various alloys. The pretreatment methods were : no treatment, treatment under vacuum and air, treatment with 50 % hydrofluoric acid and double heat tretament. The number of firings were 3, 5 and 7 repeated firings All specimens were observed by SEM and concentration of elements were analyzed quantitatively with EPMA The results of this study were obtained as follows : 1. In the groups of air-treatment, concentration of Sn were the highest and widest. A high concentration of In were in the groups of vacuum and air treatment. 2. There were no significant differences in concentration of Sn between the group of vacuum, 5 minutes hydrofluoric acid and double heat treatment. (p>0.05) 3. As the period of time of hydrofluoric acid treatment increased, not only were the trace elements reduced but the main components such as Pd and Ag were also reduced. 4. Concentration of Sn and In increased and diffused with repeated firings but 5 repeated and 7 repeated firings groups had no significant differences. (p>0.05) 5. Sn were more concentrated in the group of Ceramco porcelaion powder than Vita porcelain powder. 6. The higher concentration of trace elements in the alloy, the more increasing concentration of Sn and In in the interface.

수지접합 수복물용 합금의 피착면처리에 따른 결합력에 관한 실험적 연구

이근우,Lee, Keun-Woo 대한치과보철학회 1991 대한치과보철학회지 Vol.29 No.1

This study investigated the effects of surface treatment on the tensile bond strength of resinbonded prosthesis. The Rexillium III specimens were treated with $50{\mu}m\;Al_2O_3$ blasting. Type IV gold alloy specimens were treated with $400^{\circ}C$ heating and tin plating method. All specimens were bonded with MBAS composite resin cement and followed by immersion test into the $37^{\circ}C$ water bath for 7 days. The specimens were debonded in tension with an Instron machine and observed with SEM. The modes of failure were recorded also. The following conclusions were obtained : 1. The tensile bond strength decreased in following order. $50{\mu}m\;Al_2O_3$ basted Resillium III group, Type IV gold alloy group treated with $400^{\circ}C$ heat and tin plating type IV gold alloy group, and statistical significant differences were observed(p<0.05). 2. The tensile bond strength decreased in all groups after 7 days immersion test, but statistical significant differences were observed in Rexillium III specimens only. 3. The sharp and irregular surface were observed in Rexillium III, but $400^{\circ}C$ heat treated and tin plated groups had round and broad surface in SEM. 4. The models of bond failure were cohesive-adhesive failure mainly.

사료내의 아연과 칼슘이 돼지 부전각화증의 발생에 미치는 영향

이근우,이현범,Lee Keun-Woo,Lee Hyun-Beom 대한수의사회 1984 대한수의사회지 Vol.20 No.1

Present experiments were conducted in order to clarify the effect of dietary low zinc and excess calcium on the zinc and calcium concentrations of serum and feces, and to show the therapeutic effect of external application of zinc or soybean oil on the sk

염화제이철 용액을 이용한 베릴륨동 기판의 식각 특성

이근우(Lee Keun Woo),이병욱(Lee Byung Wook),이태성(Lee Tae Sung),이종하(Lee Jong Ha),이재홍(Lee Jae Hong),김창교(Kim Chang Kyo) 대한전기학회 2006 대한전기학회 학술대회 논문집 Vol.2006 No.10

구리와 강철의 성질을 혼합한 것과 같은 우수한 성질을 갖고 있어서 열전도율이 좋고 내마모성이 뛰어난 베릴륨동 기판(BeCu foil)에 대한 식각 특성에 관하여 연구하였다. 일반적으로 베릴륨구리에 대한 식각용액은 염화제이철(FeCl₃)이 널리 알려져 있으며, 이 용액은 농도와 온도에 따라 식각시간이 달라지게 되어 식각되는 면의 상태가 영향을 받게 된다. 염화제이철의 농도를 변화시켜 본 결과 염화제이철의 농도가 증가할수록 식각률이 증가하였고, 염화제이철에 염산(HCl)을 첨가한 결과 식각률이 증가함을 알 수 있었다. 이는 염화제이철의 성분 중에서 염산(HCl)의 농도가 식각률에 영향을 미치고 있음을 나타낸다. 또한 영화재이철의 용도가 40℃ 일때 식각륜이 가장 우수하며 식각되는 면의 상태가 매우 양호해지고 식각되는 면의 각도도 수직에 가까워진다.

상암사지(上菴寺址), 문화유적지로서의 가치에 대한 연구

이근우 ( Lee Keun Woo ) 한국동양예술학회 2016 동양예술 Vol.33 No.-

In this treatise, proving Sangam Temple site has enough cultural value of being cultural historic site; by proving these cultural values; through Goesan, Yeonpung-Hyeongam, Danwon Kim Hong-Do, Historical records of Joseon Temple, Mt. Gong-Jeong Samgam Temple restoration monument, and Sangam temple Stone inscriptions. This study will give the value of Sangam Temple site as in cultural historic site; by proving Sangam Temple site stone inscription`s character analysis. This information will base on very important character analysis form Buddhism, Song Mungyo, Samsin Mountain, Oh Yougeun, Chu Boksun. The life of Danwon Kim Hong-Do had been studied and divided into several different time line in this treatise; Kim Hong-Do with Seungjeongwon Ilgi(the diary of the Royal Secretariat), Historic records of Joseon Temple Mt. Gong-Jeong Sangam Temple Restoration Monument ; record of assigned Sangam Temple head Buddhist monk is from Governor-General of Korea`s official gazette; Yeonpung, Mungyeong, Joryeong, Ihwaryeong, Korean War in Jeomchon area, are from institute from Military History, in Ministry of National Defense, 6.25 Korean War (4) 『Delayed Military Operation in Geumgang Sobaek Mountain Range』 and 『Battle in North Chungcheong』 from North Chungcheong Province Defense Council. These contents are not inference; it is based on actual historic records and investigation; through these studies, Sangam temple has not only the religious historic site, it has the valuable cultural historic site as well as artistic and historic beauty; and more widely can be reconsider the value of historic temple site. When the writer was preparing this treatise Study of Sangam Temple Site; The value of Cultural Historic Site writer used objective argumentum of research methodology, however, to reduce all the objective and reliability in this treatise, year 2014 December 7th Sunday, start to investigate Sangam temple site and ended in year 2016 June 12th Sunday, total number of 11 investigation has been held and try to prove the value of cultural historic site. Also during the investigation, temple site, Buddhist sanctuary foundation stone, stone inscription, roof tiles, and other relics of the past time has been found and verified and attempt to reduce the lack of the information. Sangam temple was built during Sillyeo (Silla or Goryeo), it has long history. Right now, Sangam temple is placed in Baekdudaegan Mountain Range, Mt. Jo-Ryeong (1,026), 8th ridge (about 845M from sea level); head office temple and brach temple of Beopju Temple and the property of Korean Buddhist Jogye Order; the address is Chungcheongbuk-do, Goesan-gun, Yeonpung-myeon, Wonpung-ri, 743-1.

장외파생상품거래를 위한 유연한 의사결정지원시스템 아키텍처 설계에 관한 연구: A은행 사례

이근우 ( Keun Woo Lee ),양근우 ( Kun Woo Yang ) 한국정보시스템학회 2011 情報시스템硏究 Vol.20 No.1

Model-based decision support system (DSS) has acted as a crucial role in strengthening the business competitiveness by providing a way of modeling and solving real-world decision problems in a quantitative and scientific manner. It is even more important for trading OTC derivatives, which requires extensive financial-engineering expertise while actively reacting to the continuously changing financial market . This paper proposes a flexible model-based DSS architecture that can support user-friendly interface for executing and analyzing the models and can adapt to the changes of financial market seamlessly. For user-friendliness, we implement the user-interfaces (UIs) using Microsoft Excel, a very widely used spreadsheet program for its great generality and extensibility. Users can utilize the analysis results of DSS or reprocess them for their special needs through the UIs in the form of familiar spreadsheets easily. For adaptiveness to the markets, the proposed architecture is constructed based on the object-oriented concepts, which enables such changes as release of a new financial product can be updated into the system without any delay at the lowest cost. We investigate the practical benefits and limitations of the proposed architecture by a case study on the construction of Model-based Trading Support System (MTSS), performed by a commercial bank in Korea.

프르브유닛 소자용 블레이드형 팁 제조방법

李根雨(Keun-Woo Lee),金昌敎(Chang-Kyo Kim),李在洪(Jae-Hong Lee) 대한전기학회 2007 전기학회논문지 Vol.56 No.8

Beryllium copper has been known to be an important material for the various fields of industry because it can be used for mechanical and electrical/electronic components that are subjected to elevated temperatures (up to 400℃ for short times). Blade type tip for probing the cells of liquid crystal display(LCD) was fabricated using beryllium copper foil. The dry film resist was employed as a mask for patterning of the blade type tip. The beryllium copper foil was etched using hydrochloric acidic iron-chloride solution. The concentration, temperature, and composition ratio of hydrochloric acidic iron-chloride solution affect the etching characteristics of beryllium copper foil. Nickel with the thickness of 3㎛ was electroplated on the patterned copper beryllium foil for enhancing its hardness, followed by electroplating gold for increasing its electrical conductivity. Finally, the dry film resist on the bridge was removed and half of the nickel was etched to complete the blade type tip.