저항방사열계 적외선 감지기 제조를 위한 바나듐 산화막의 전기적 특성 및 유전 특성

박재홍,최용남,최복길 공주대학교 생산기술연구소 2000 論文集 Vol.8 No.-

For fabrication of bolometric infrared detector, thin films of vanadium oxide(VO_(X)) was deposited by r.f. magnetron sputtering from V_(2)O_(5) target in 10% gas mixture of argon and oxygen, and in-situ annealed in vacuum with different temperatures and times. Crystall structure and surface morphology of films were characterized through XRD and SEM. In order to measure the current-voltage characteristics, temperature dependence of conductance, and dielectric properties of vanadium oxide, Al/VO_(X)/Al sandwich devices structure was adopted. The films prepared below 200℃ were amorphous, and those prepared above 300℃ were polycrystalline. Above 3×10^(4)V/cm conduction of vanadium oxide is limited by space charge formed near electrode.? Conduction mechanisms above 10^(5)V/cm are due to Schottky emission and Fowler-Nordheim tunneling effects. Resistance and capacitance of grain boundary are decreased with increasing annealing temperature. Oxygen vacancy is related to the localized state and non-stoichiomeric of vanadium oxide.

저항방사열계 적외선 감지기 제조를 우한 바나듐 산화막의 전기적 특성 및 유전 특성

박재홍,최용남,최복길 공주대학교 생산기술연구소 2000 論文集 Vol.8 No.-

For fabrication of bolometric infrared detector, thin films of vanadium oxide(VO_x) was deposited by r.f. magnetron sputtering from V_2O_2 target in 10% gas mixture of argon and oxygen, and in-situ annealed in vacuum with different temperatures and times. Crystal structure and surface morphology of films were characterized through XRD and SEM. In order to measure the current-voltage characteristics, temperature dependence of conductance, and dielectric properties of vanadium oxide, Al/VO_x/Al sandwich devices structure was adopted. The films prepared below 200℃ were amorphous, and those prepared above 300℃ were polycrystalline. Above 3×10^4V/cm conduction of vanadium oxide is limited by space charge formed near eletrode. Conduction mechanisms above 10^5V/cm are due to Schottky emission and Fowler-Nordheim tunneling effects. Resistance and capacitance of grain boundary are decreased with increasing annealing temperature. Oxygen vacancy is related to the localized state and non-stoichiomeric of vanadium oxide.

ASEA-SKF 래들용 고알루미나 내화재의 용손성향

박홍채,이윤복,양태영,장윤식,오기동 釜山大學校生産技術硏究所 1997 生産技術硏究所論文集 Vol.53 No.-

ASEA-SKF 래들에 사용된 고알루미나 내화물의 광물 및 화학적 변화를 화학분석, 현미결관찰, X-선회절분석으로 조사하였다. 미사용 벽돌의 주요 광물상은 α-Al₂O₃, mullite, tridymite이었다. 가동면에서 SiO₂결정상이 소실되었으며 mullite와 α-Al₂O₃가 다소 감소하였고 2FeO·SiO₂와 hercynite, FeO, Cr₂O₃상이 생성되었다. 침식율은 강종에 따라 다소간 차이가 있었으며 용강 SF-45와 60분간 반응시켰을때 SK36벽돌의 침식율은 75.9%인 반면에 SK38벽돌의 침식율은 20.47%이었다. 대부분의 용손벽돌에서 가동면으로부터 내부로 감에 따라 열적 및 화학적 스폴링으로 인하여 미세균열이 존재하였다. Mineral and chemical changes of alumina refractories used in ASEA-SKF ladle were examined by chemical analysis, microscopy and X-ray diffraction method. Main minerals in unused high alumina runner bricks were α-Al₂O₃, mullite and tridymite. In working face of high alumina runner bricks, SiO₂phase was not observed, mullite and α-Al₂O₃phases more or less decreased. On the other hand, 2FeO·SiO₂, hercynite, FeO and Cr₂O₃phases were formed. Th corrosion of high alumina runner bricks showed different behavior by using various types of iron melts. Expecially, corrosivites of SK36 bricks and SK38 bricks, which immersed in SF-45 Iron melts for 60min, were 75.9% and 20.47%, respectively. Microcracks in high alumina runner bricks increased from the working face to the inside due to thermal and chemical spalling.

만성적 소음폭로가 근로자의 혈압에 미치는 영향

김복연,김천태,이중정,박홍진,김창윤,강복수 大韓産業醫學會 1996 대한직업환경의학회지 Vol.8 No.1

The question of an association between occupational noise exposure and blood pressure has important public health implications. The harmful effects of hypertension are well known and noise is considered the most pervasive problem of all occupational exposures in Taegu City, Korea. A cross-sectional study on the effect of long-term noise exposure on blood pressure was done for 276 noise exposed workers(203 male workers, 73 female workers). Long-term noise exposure was measured by cumulative noise exposure level and noise-induced hearing loss. Hearing loss = 500Hz+2×1,000Hz+2×2,000Hz+4,000Hz -------------------------------------- 6 Questionnaire was administered to the workers, which includes age, sex, occupational history on the noise exposure, habits on alcohol drinking and smoking, practice of regular exercises, family history of hypertension. Type A behavior, question on stress, height, weight and blood pressure were measured. Serum triglyceride and low density lipoprotein(LDL) were also measured. Audiometry was done in the closed booth at 1,000, 2,000, 3,000, 4,000, 6,000, 8,000, 1,000 and 500Hz in order. Multiple logistic regression analysis revealed that cumulative noise exposure level(p〈0.05), serum triglyceride(p〈0.01), age(p〈0.01) and family history of hypertension(p〈0.05) predict hypertension (systolic blood pressure : 160㎜Hg or above, or diastolic blood pressure : 95㎜Hg or above) in male workers. In female workers, serum triglyceride(p〈0.01), LDL(p〈0.01) and family history of hypertension(p〈0.05) were predictors of hypertension (systolic blood pressure : 160㎜Hg or above, or diastolic blood pressure : 95㎜Hg or above). As the number of female workers with hypertension was too small, the multiple logistic regression was done according to hypertension criteria of systolic blood pressure greater than or equal to 140㎜Hg, or diastolic blood pressure greater than or equal to 90㎜Hg. Based on this criteria, cumulative noise exposure level(p=0.055) and age(p=0.057) predict hypertension. It is suggested that long-term noise exposure which was calculated by cumulative noise exposure level was a significant predictor of hypertension in noise exposed workers.

시표현의 화법분석에 있어서 P-언어의 역할

김복영,박병주,홍지석 홍익대학교 산업디자인 연구소 2004 미술디자인 논문집 Vol.- No.9

The paper aims to ascertain the conditions and rules for the visual expression to produce meaning, as though it were to be an analogical level of linguistics. For this, the researchers needed to analyze the visual artifacts within the context of paradigms and syntagms, with the meta-critical level of visual languages, as a means. As a result, the researchers are ready to propose that there are a system of P-Languages, which play an active part in meta-linguistical level, according to their `morphodynamical principles'. As a fact, the existence of P-Languages could be verified through the analysis of some testing material made under the rigid construction. To scrutinize into the field of visual space, we made use of 〈The Table of Constant and Orbit of Syntagms〉 prepared before for the purpose of our research. The above observation gave an important consequences to our present question. Accordingly, in short, P-Languages seem to produce a series of paradigms and syntagms for the visual expression which, in turn, make conditions and rules of meaningful expression, through their generative and transformational structures which is activated by means of P-Languages for themselves.

Racket 運動時의 反應時間과 運動速度 改善을 爲한 Simulator 「SQT」에 關한 硏究

허복,蔡鴻遠,李來華,李敏炯,金基學,鄭相澤,朴宇奎 慶北大學校 體育科學硏究所 1986 체육과학연구지 Vol.2 No.-

The main purpose of this study was to improve greatly the most important reaction time(RT) and speed of movement (SM) at racket exercise by making program for simulator super quality training (S.Q.T) and applying it. The subjects employed were 25 male athletes composed of soccer players 8, volleyball players 7, shooting players 2, soft-tennis players 2, gymnastics player 1, and rugby football player 1 at the Kyungpook National University. We devided each sport player half and half by means of their pre-testing reaction time, and the subjects were devieded into experimental and control group. Experimental group was drilled by using light stimulus simulator training method and control group was drilled by using sound stimulus simulator training method. The training was practiced 20∼30 minutes a day regularly and 5 times a week for 5 weeks. Two groups practiced concentrically experimental learning by using light and sound simulator equipment by S.Q.T. program under equal condition. The propriety on the training effect was investigated by longitudinal analysis of results tested before and after experiment. As the result of the experiment, superiority and inferiority of two groups was evaluated by trying crosssectional analysis. The results obtained were summarized as follows: 1. Reaction time Experimental group; The performance of this group was greatly improved after experiment. Control group; The performance of this group was greatly improved after experiment. Comparison of two groups; Leftward simple completion time showed a significant difference (p<.01), but the other elements did not showed it. As a whole, experimental group was superior to control group, but statistics showed little difference between the two groups. 2. Speed of movement Experimental group; The performance of all elements were improved after experiment(over p<.05). Control group; The performance of this group was improved at only 4 of 9 elements after experiment Comparison of two groups; The performance of service and dash showed a significant difference (p<.01) and the others did not showed it. But as a whole, experimental group was superior to control group in their performance. 3. Viewing Variance and correlation coefficient at the change of RT and SM, there were differences in the variance. This means that the standard deviation is great; i.e. the individual difference is great. The lower correlation coefficient means that correlationship is low in the performance before and after experiment: i.e. it means that individual difference was decreased because the gap of two groups, correlation coefficient became less. Especially, statistics showed that the record of the lower recorded players could be shortened to a maximum.

속성 퇴비화에 관한 연구

임채규,박경수,김홍섭,노영복 조선대학교 기초과학연구소 1988 自然科學硏究 Vol.11 No.1

This experiment was conducted to fine out the rapid composting method and the effects microorganism agent. The results were summarilized as follows; 1. Each temperatures of every composts highest rised at the 5 days during the experiment composting. 2. Composting temperature of the more 60℃ was killed the harmful lavar and pathogenic microorganisms. 3. The lowest C/N ratio was No.2, among the each treatments. 4. C/N ratio of the each treatments were same results of the general compost C/N ratio. 5. The synthesized of these results were recognized the effects of microorganism agent and the each treatments were showed the more rapid composting then general compost.

비정상 질확대경검사 소견을 보이는 환자에서 환상투열요법의 직접적 적용에 관한 연구

우헌탁,이철민,박교훈,조용균,최훈,김복린,이홍균 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.2

Objective: Large Loop Excision of the Transformation Zone (LLETZ) has been widely used for evaluating cervical dysplasia/cancer. We performed this study to evaluate if colposcopically suspected cervical high-grade dysplasia or cancer could be directly evaluated and treated with LLETZ. Methods: 93 women who were scheduled for colposcopic evaluation because of an abnormal cervical cytology report were included in the study in Sanggye Paik Hospital from Jan to Dec 2001. Mean age of the study population was 38.6±9.0. colposcopy directed punch biopsy was not performed and histologic diagnosis was made by LLETZ. Sensitivity and specificity of colposcopic evaluation was calculated and compared with those of cervical cytology. Results: On histopathological examination by LLETZ, 11(11.8%) patients had invasive cancers including 3(3.2%) adenocarcinomas. The sensitivity and specificity of colposcopy for the detection of cervical dysplasia or cancer was 71.7% and 72.3% respectively, wile those of cytology was 56.5% and 74.5% respectively. Conclusion: LLETZ may be adequately performed for the diagnosis and treatment of cervical dysplasia/cancer based on the results of pap smear and colposcopy without punch biopsy. Cost benefit might be anticipated while cost-effectiveness analysis is necessary in the future.

MgO-Cr₂O₃캐스타블의 화학적 손상에 관한 연구

최익대,이윤복,박홍채,오기동 부산대학교 생산기술연구소 2000 生産技術硏究所論文集 Vol.59 No.-

마그-크롬질 캐스타블에 대한 내알칼리성 증진에 의한 수명 향상의 가능성을 검토하였다. 골재로서 전융 알루미나, 크롬질, 소결 스피넬, 마그-크롬질, 마그네시아질 순으로 알칼리 침식에 대한 저항성이 우수하였다. 마그-크롬질은 다른 골재에 비하여 알칼리에 대한 침식저항성 뿐만 아니라 열충격에 대한 저항성이 양호하였다. 장시간 적용 시험시 β-2CaO · SiO2.3CaO · SiO2 및 K2SO4가 존재하였고 조직 취화를 초래하여 가동면에서 손상을 가속하였다. 전융 마그네시아를 사용한 경우 소결 마그네시아질에 비하여 재질 변경 및 조직 치밀화로 인하여 알칼리에 대한 침식 억제 효과가 있었다. For long life of applications in MgO-Cr2O3 castables, the improvement of chemical resistance against alkali salts were investigated. Chemical resistance against alkali salts was excellent in order, i.e fused alumina, chrom ore, sinterded spinel, Magnesia-chrome, magnesia based castables. magnesia-chrome based tastable was comparatively good in the chemical attacks and the thermal resisatnce. As working for long time, β-2CaO · SiO2, 3CaO · SiO2 and K2SO4 were existed, and they accelerated chemical wear in the working area of magnesia-chrome castables caused the degreaded microstructure. The chemical resistance of fused magnesia in MgO-Cr2O3 castables showed the more excellent than that of the sintered magnesia due to the densification of mircrostructure and the change of materials

마하피닝 처리에 의한 기계구조용 합금강의 피로균열전파 지연효과

김민건,임복규,박홍기,황중각 강원대학교 산업기술연구소 2006 産業技術硏究 Vol.26 No.B

Mach peening treatment is one of the various kinds of techniques to improve the fatigue properties. The mach peening process gives high-level work hardening and compressive residual stress near the surface layer, improving the fatigue strength. In addition, this treatment reduces slip bands that initiate the fatigue cracks near the surface. During impingement, a plastic indentation surrounded by a plastic zone is formed. Mach peening treatment characteristic is less energy consumption and is an environmental friendly processing methods that is not accompanied by pollution. It is machining process that can prevent fatigue fracture beforehand in structure using already as well as process of production. The test results showed that fatigue crack propagation delay appeared by drilling type 43%, mach peening type 110%.