연속파형 Nd:YAG 레이저에 의한 인코넬 600의 용접 공정변수의 연구

배신철,유영태,송성욱,신호준,나기대 朝鮮大學校 機械技術硏究所 2004 機械技術硏究 Vol.7 No.1

The laser welding process is one of the most advanced manufacturing technologies owing to its high speed and deep penetration. Welding characteristics of Inconel 600 Alloy using a continuous wave Nd:YAG laser are experimentally investigated. The major process parameters studied in the present laser welding experiment were position of focus, laser power, travel speed. The gap and offset maintained as small as possible. Optical microscope were used to investigate the microstructures of the welded zone. The follow conclusions can be drawn the laser power and travel speed have a pronounced effect the fusion zone size and shape.

레이저 표면경화면과 마찰면의 프랙탈 차원 적용에 관한 연구

배춘익,옥철호 慶南專門大學 2001 論文集 Vol.29 No.1

Azathioprine에 반응을 보인 류마티양 관절염에 의한 경막염(Pachymeningitis)1예

배광봉,이정호,이정찬,곽상혁,강정현,김철희,김현수,김종숙,조덕연,김삼용 충남대학교 의과대학 지역사회의학연구소 1999 충남의대잡지 Vol.26 No.1

Rheumatoid arthritis frequently involves the cervical spine and may lead to neurologic impairement. However, direct involvement of CNS structures by inflammatory cells has been reported infrequently. The prevalence of this complication of rheumatoid arthritis is unknown. Inflammatory CNS involvement in rheumatoid arthritis reportedly occurs in the setting of longstanding, active, erosive articular disease and is accompanied by extracranial and extraspinal nodules and vasculitis. This is diagnosed by radiologic finding of CNS nodules or meningeal thickening and by biopsy or autopsy. Treatment with corticosteroid, cytotoxic agent or surgical decompression is helpful. But the majority of patients die within several months of onset of neurologic symptom. Recently, we experienced a case of pachymeningitis caused by rheumatoid arthritis, which resolved repeatedly with azathioprine treatment.

기계구조용 탄소강의 표면개질을 위한 펄스 YAG 레이저의 적용

배춘익,옥철호 慶南專門大學 2000 論文集 Vol.28 No.1

액상 에피탁시법으로 成長시킨 GaAs의 Photoluminescence

裵仁鎬,李哲旭,金仁洙 嶺南大學校 基礎科學硏究所 1992 基礎科學硏究 Vol.12 No.-

Eptaxial layers of undoped GaAs were grown by liquid phase epitaxity(LPE) method on semi-insulating GaAs(100) substrates. GaAs epitaxial layers were characterized by photoluminescence(PL). In the as-grown LPE samples, the emission peaks observed at 1.511, 1.492 and 1.478eV. A PL peak at 5.11eV attributed to the excitons bound to neutral acceptors, and the peaks at 1.492 and 1.478eV were related to carbon and germanium, respectively. The crystal quality of the samples with gallium baking were superior to without baking. Increasing the excitation intensity, the exciton peak varies sensivity, but the peaks due to impurities no significant change. As the anneal temperature is increased, the crystal quality of samples are reduced.

麥酒麥의 栽培現沿과 展望

文永培,李喆浩 진주산업대학교 1982 論文集 Vol.20 No.-

This study was conducted to grope a scheme for achieve self-sufficiency with investigation into status of cultivation of brewery barley. The results were summarized as follows: 1. Area under cultivation and productive quantity of malting barley are to be on the increase every year under present condition, this situation will be continuous for some ttime (Table 1). 2. The self-sufficiency ratio of brewery barley was low, therefor it is essential to be promote production (Table 5). 3. The price of domestic malting barley is remarkable higher than that of imports(Table 6). 4. As the quality of domestic multing barley is inferior in comparison with that of imported articles, it is urgent to improve the quality of malting barley(Table 7). 5. The production of malting barley have a good prospect for the present in proportion to the increase of one's consumption of beer.

種薯의 크기, 切斷 및 Curing處理가 감자의 生育 및 收量에 미치는 影響

李喆浩,文永培 진주산업대학교 1982 論文集 Vol.20 No.-

감자種薯의 Curing處理, 種薯의 크기, 切斷效果 等이 감자의 塊莖形成(收量)에 미치는 影響을 究明하기 위하여 1982年 晋州農林專門大學 構內에서 男爵品種을 供試하여 處理한 結果를 要約한면 다음과 같다. 1. Curing處理는 發芽率과 腐敗 및 健全發芽 個體比率에 影響을 주지 않았다. 2. 어느 處理區에서나 定植期가 빠를수록 增收되는 傾向이었다. 3. 種薯處理에 있어서 全形薯가 切片薯 보다 11% 가량 增收되는 傾向이였다. 4. 種薯의 크기는 30∼50g에서 감자의 생육이 良好하고 收量이 많았다. To Study the effect co curing, cutting and tuber size on the tuber formation of potato, this experiment was carried out with Irish Cobbler at the campus of Jin ju Agricuttural and Forestry Technical Collegs, in 1982. Results gained would be summarized as followings: 1. In curing treatments, growths were similar to non-treatments in uniformity of sprouting and percentage of rotten tuber pieces and of healthy sprouted tuber pieces. 2. In all treatments earlier transplanting resulted higher growth and yield of plant. 3. In whole tuber treatments marketable tuber yields were increased by 11% more than tuber piece treatment. 4. In the 30 gram and 50 gram pots, the growth and yield were increased in comparison with 15 gram. From the results of this study, it concluded that the tuber could be planted heavier than 30 gram for increasing the yield.

Coronal flaring 전, 후의 근관세척효과

황호길,배성철,조영린 大韓齒科保存學會 2003 Restorative Dentistry & Endodontics Vol.28 No.1

The objective of this in vitro study was to evaluate the efficacy of a Ca(OH)_2 removal before and after early coronal flaring using different types of instruments. 100 plastic blocks with 30°artificial curved canals were used in this study and randomly divided into a control group and 4 experimental groups(GG, OS, GT, PT Group) 20 teeth each. The canals were instrumented, and Ca(OH)_2 was temporary filled into the each canal. Irrigation was performed with Max-i-Probe 25-, 30-gauge probes before and after recapitulation. The results of this study were as follows: 1. There were no significant difference among the groups in size of irrigating needle(p<0.05). 2. There was a significant difference between before and after recapitulation regardless size of irrigating needle(p<0.05). 3. Before recapitulation, there was a significant difference between 25- and 30-gauge needle in all groups(p<0.05). 4. After recapitulation, there was a significant difference between 25- and 30-gauge needle in the control group(p<0.05). But there were no significant difference among the experimental groups. It is concluded that the effectiveness of canal irrigation was decided to the depth of irrigating needle into the canal. The effect of canal irrigation tend to facilitate by the early coronal flaring. The recapitulation was the most effective during canal irrigation regardless the size of irrigating needle. Therefore, the recapitulation is a mandatory way to facilitate the effectiveness of canal irrigation during canal enlargement.

레이저 경화면의 형상특징 해석을 위한 프랙탈 차원의 적용

옥철호,조연상,배춘익,박흥식,전태옥 동아대학교 생산기술연구소 2000 生産技術硏究所硏究論文集 Vol.5 No.2

The determination of surface topography is believed to be extremely important in the areas of contact mechanics, adhesion and friction. In order to describe topography of various frictional surface, the harding test was carried out under different experimental conditions in dry friction. And fractal descriptors was applied to frictional surface of laser modified steel with image processing system. These descriptors to analyze surface structure are fractal dimension. Surface fractal dimension can be determined by sum of intensity difference of surface pixel. Topography of frictional surface can be effectively obtained by fractal dimensions.

Coronal flaring 전, 후 초기근관장 파일크기의 분석

황호길,박찬호,배성철 大韓齒科保存學會 2003 Restorative Dentistry & Endodontics Vol.28 No.1

The purpose of this study was to compare the inital apical file(IAF) first file that fits to the apex in each canal before and after early flaring to analyze if the size of file to fit to the apex would increase after flaring. Eighty anterior teeth with complete apical formation and patent foramens were selected. The samples were randomly divided into 4 groups(GG, OS, GT, PT Group) of 20 teeth each. A file was fit to the apex in each canal and that size recorded. Radicular flaring were completed using different types of instruments. After flaring a file was again fit to the apex in the same manner as before and its size recorded. The results of this study were as follows: 1. The mean diameter of IAF before flaring(file diameters in mm ×10^-2) was 19.81±8.32 before and 25.94±9.21 after(p<0.05). 2. The increase in diameter of IAF was approximately one file size for all groups. 3. Ranking of increasing diameter of IAF were GG>GT>OS>PT Group. There was a statistically significant difference between before and after flaring(p<0.05). 4. Ranking of the time for flaring were GG>GT>OS>PT group. There was a statistically significant difference between GG group and other groups(p<0.05). 5. In the case without change of IAF diameter, they showed decrease in force after flaring when IAF was pulled out from root canal(p<0.05). This study suggested that early radicular flaring increases the file size that is snug at the apex, and awareness of that difference gives the clinical a better sense of canal size. Early flaring of the canal provides better apical size information and with this awareness, a better decision can be made concerning the appropriate final diameter needed for complete apical shaping.