Reliability Considerations of Hybrid Power Systems for Critical Facilities

Choi, Se Jin · Ham, Young Hwan · Kim, Myung Chin 충북대학교 컴퓨터정보통신연구소 2008 컴퓨터정보통신연구 Vol.27 No.2

본문참고

나노/마이크로 압입 시험에 의한 플라즈마 세라믹 용사코팅의 특성 평가

최세영(Se-Young Choi),채영훈(Young-Hun Chae),김석삼(Seock-Sam Kim) 한국트라이볼로지학회 2003 한국트라이볼로지학회 학술대회 Vol.36 No.-

The most controversial topics in plasma sprayed ceramic coating systems are recently mechanical properties such as bond strength, cohesive strength, toughness and so on. In this research, critical fracture load(Pc) and interface toughness(Ks) of four coatings materials were computed from the applied load, crack length and Young's modulus data which were measured by micro-vickers and nano indentation test. It is reasonable to consider the Pc value as comparison data of bond strength, and the Kc value, considering a trace of indent in the interface, was computed by a modified (E/H)I<SUP>½</SUP> ratio. In the case of the high loads (9.8N and 19.6N) in the Al₂O₃+13%TiO₂ coating, the critical point(Pco) at which the coating was broken was found. Also, used by a XRD phase analysis, we checked a change of coating' s properties, predicting a possible change of the phases in plasma sprayed coating.

複合 韓藥劑 淸籬滋坎湯의 抗癌效果 및 作用機轉 糾明

Cho, Kyung-Sam,Kim, Si-Young,Park, Jai-Kyung,Choi, Seung-Hoon,Chung, Se-Young,Yoon, Hwi-Joong 경희대학교 동서의학연구소 1999 INTERNATIONAL SYMPOSIUM ON EAST-WEST MEDICINE Vol.1999 No.1

Kyung Sam Cho¹Si Young Kim¹, Jai Kyung Park²,Seung Hoon Choi³,Se Young Chung⁴, Hwi Joong Yoon¹¹College of Medicine, ²East-West Medical Research Institute, ³College of Oriental Medicine, ⁴College of Pharmacology, Kyung Hee University,Seoul, Korea. The Anti-cancer Effect of Oriental Medicine Chung-Ri-Ja-Gam-Tang in the Mouse with Metastatic Lung Cancer. Proceedings of International Symposium on East-West Medicine, Seoul. 231-243, 1999.-The oriental medicine Chung-Ri-Ja-Gam-Tang is an herbal medicine which has been used for pulmonary diseases and known as having immune stimulatory effects. It has been known effective in lung cancer. So we studied the effects and the mechanisms of this herbal medicine it the mouse with metastatic lung cancer. The metastatic lung cancer of the mouse was produced with melnoma cell line(B16BL/6).5×10□/mouse tumor cells were injected intravenously to the CDF1 mouse via tail vein. The mice were divided 4 groups. The first group was treated with 50mg/kg extract of Chung-Ri-Ja-Gam-Tang per oral for 10 days after cancer cell injection, second group treated with saline after cancer cell injection, the third group with medicine without cancer cell, and the last group with saline only. After 10 days treatments some of the mice were scarificed and the lung and spleen was removed. The survival duration, weight change, the number of metastatic cancer nodule of the lung, the NK cell activity, the capacity of cytokines(INF-γ,INF-α,IL-2) production and the proliferation activities of mouse lymphocytes were measured. The surival times of the group 1 mice were longer and the weight loss was less than the group 2 significantly. The number of the metastatic nodule of the lung were decresed in the group 1 than the group 2. The production of INF-γ,was increase in group 2 than group 3 and 4, IL-2 production was increased in group 1 than group 2,3,4 significantly. There was no difference in TNF- α production and proliferation activity of lymphocyte in each group. The NK cell activity was significantly increased in group 1 than group 2,3,4. We conclude that the Chung-Ri-Ja-Gam-Tang has the effect of increasing the NK cell activity of the CDF1 mouse with metastatic lung cancer(B16BL/6). And it is suggested that the increased production of the IL-2 is the mechanisms of enhanced NK cell activity.

논리 프로그래밍과 DBMS 결합에 따른 순환문제해결에 관한 연구

崔宰赫,權寧淡,朴世明 新羅大學校 1990 論文集 Vol.29 No.-

Recently, the design and implemenation of a logic programming system capable of handing very large knowledge bases will be present. The loose coupling is an act without resursion. This paper introduces the purpose of loose coupling system with recursion. This system is implemented by adding a sub-process SELECTOR and particular two system calls. This can be used to avoid high cost in consructing a new large full integration system and coupling system of recursion problem.

고령토로부터 알루미나 추출에 관한 연구(Ⅲ):염산에 의한 추출

최세영,이용근,이희수,김형국 연세대학교 산업기술연구소 1992 논문집 Vol.24 No.1

The preparation conditions of alumina powder extracted by hydrochloric acid from domestic San-Cheong kaolin have been investigated. In order to obtain best conditions to extract alumina by hydrochloric acid, experiments carried out with various acid concentrations, reaction temperatures, reaction times, and pH. The optimum conditions were 20 wt.-% for hydrochloric aicd concentration, 100℃ for reaction temperature, 7hrs for reaction time and pH8. The yield of alumina found to be 89.2wt.-% under these conditions. Two drying methods, direct and ethanol distillation drying method to control the precipitated agglomeration have deen compared. The ethanol distillation drying method revealed more narrow particle size distribution and less agglomerate than the direct drying method.

소형환편기 자동화기술개발에 관한 연구

최세환,장승호,허유,박준희,권영하 경희대학교 산학협력기술연구원 1995 산학협력기술연구논문집 Vol.1 No.-

소형환편기의 자동화기술을 위해 편환을 이동시킬 수 있는 편침과 cam을 편환이송용 장치를 고안하였다. 위편기의 편환이송 mechanism을 해석하고 소형환편기의 물리적 모사를 통해 편침과 cam의 형상을 최적화하였다. 편환이송장치를 사용하여 편물에 다양한 조직을 편성할 수 있는 편기의 개발이 가능하도록 하였다. The latch needle and cam are newly designed and manufactured to transfer the loop for automation of small circular knitting machine. The loop transfer mechanism is analized by the simulation of needle motion on the V-bed flat knitting machine to which optimum designed cam is attached. This loop transfer mechanism can be applied to small circular knitting machine for automation and variable knitted structure.

복합레진의 수리 시 표면처리가 결합강도에 미치는 영향

최정인,김영재,김정욱,이상훈,김종철,한세현,장기택 大韓小兒齒科學會 2008 大韓小兒齒科學會誌 Vol.35 No.4

본 연구의 목적은 표면처리가 기존의 레진과 새로운 레진 사이의 전단결합강도에 미치는 영향을 평가하는 것이다. 준비된 레진 시편을 6군으로 임의로 배분하여 각각의 표면처리를 한 후 수리용 레진을 축조하였다. 일주일간 보관 후 전단결합강도를 측정하였고 일원분산 분석법으로 통계처리하여 다음과 같은 결과를 얻었다. 1. 3군과 4군(air abrasion)은 1군(산부식)에 비해 전단결합강도가 유의하게 높게 나타났다(p<0.005). 5군과 6군(diamond bur)은 1군(산부식)에 비해 높은 전단결합강도를 나타냈으나 통계적으로 유의하지 않았다(p<0.005). 2. 2군(자가부식 접착제)은 1군(산부식)에 비해 전단결합강도가 낮게 나타났으나 유의한 차이는 없었다(p<0.005). 3. 3군(air abrasion)과 4군(air abrasion +산부식)에서 전단결합강도의 차이는 유의하지 않았다(p<0.005). 4. 5군(diamond bur)과 6군(diamond bur+산부식)에서 전단결합강도의 차이는 유의하지 않았다(p<0.005). 결론적으로,복합레진의 수리 시 air abrasion으로 표면처리를 했을 때의 결합강도가 가장 높았고,산부식 방법과 처리여부는 수리강도에 유의한 영향을 미치지 않았다. The purpose of this study was to evaluate the effect of surface treatment on the shear bond strength between new and old composite resin. The prepared resin specimens were separated 6 groups, and each group then received a different surface treatment. Then the repair material was added. Shear bond strengths for repair were measured after 7 days and the results were analyzed by using one way ANOVA. The results were as follows ; 1. Group 3, 4(air abrasion) showed significantly higher shear bond strength than Group l (phosphoric acid)(p<0.05). Group 5, 6(diamond bur) showed higher bond strength than Group l(phosphoric acid) but not significantly different(p<0.05). 2. Group 2(self-etching adhesive) showed lower shear bond strength than Group 1 (phosphoric acid) but not significantly different (p<0.05). 3. There was no statistically significant difference between Group 3 (air abrasion) and Group 4(air abrasion + etching). 4. There was no statistically significant difference between Group 5(diamond bur) and Group 6(diamond bur+etching). In conclusion, the surface treatment with air abrasion resulted in higher repair bond strength than other methods. Repair bond strength was not significantly affected by acid etching.

생체 활성 A-W glass-ceramics에 대한 ZrO₂첨가효과

최세영,김정한 연세대학교 산업기술연구소 1992 논문집 Vol.24 No.1

The effect of the various ZrO₂contents on the mechanical properties and the behavior of densification and crystallization were investigated in the Bio-active Apatite-Wollastonite glass-ceramics in the system of MgO-CaO-P₂O5-SiO₂-CaF₂. The precipitated crystals in thermally treated A-W glass-ceramics were oxy/fluoraptite ?? and β-wollastonite[β-CaO·SiO₂]. Increasing the ZrO₂ contents up to 7Wt%, the mechanical properties were increased, but the bioactivity was decreased. For investigating the bio-activity, A-W glass-ceramics were soaked in the simulated body fluid (SBF solution) for 7 days at 36.5℃, and resulted in the formation of apatite layer of about 5㎛.

도심 교차로 노면 지표유출수의 초기수질특성에 관한 연구

최상용,고광백,이지영,임세호 한국환경과학회 2006 한국환경과학회지 Vol.15 No.4

항암제(Adriamycin, Cyclophosphamide, 5-Fluorouracil)로 유발된 흰쥐의 간독성에 대한 Squalene의 효과

최영복,김종세,윤중식 조선대학교 기초과학연구소 1998 自然科學硏究 Vol.21 No.1

The objective of the present study was to investigate the cytotoxicity of Adriamycin〔ADM〕. Cyclophosphamide〔CP〕, 5-Fluorouracil〔5-FU〕 in mouse liver cells (group A, B, c), and the protective effect of squalene to the hepatocytes to which ADM, CP, and 5-Fu-induced cytotoxicity(group A-1, B-1, C-1) was examined by transmission electron microscope. In the group A, The cisternae of rough endolplasmic reticulum(RER) and smooth endoplasmic reticulum(SER) are dilated/disoriented at 24 hours and 48 hours. The inner and outer membrane of mitochondria are detached or destructed, and attached ribosomes of RER are diminished in number. The cisternae of the SER are dilated, and the cristae of mitochondria are disrupted at 72 hours and 96 hours. In the group A-1, the cisternae of the RER and the SER are dilated at 24 hours. The cisternae of the SER are dilated at 48 hours. The cell organelles of hepatocytes are recovered from cytotoxicity at 72 hours. At 96 hours, hepatocytes were simillar to those of normal hepatocytes. In the group B, the cisternae of RER were partially destructed and attached ribosomes were remarkable decreased at 24 hours. A number of the mitochondria were dilated and increased in number, the filamentous materials also detected at 72 hours. In the group B-1, the difference between the normal and the treated groups were not detected at 24 hours, but the few mitochondria were expanded at the 72 hours. In the group C, the nucleus was destroyed at 24 hours and 48 hours group, however, somewhat repaired at 72 hours group. The dilated inner cavity and the irregular lamellae of the RER were observed continually until 72 hours group. The inner cavity of the SER were dilated in all groups. However, the destroyed and the normal membrane were observed simultaneously at 72 hours group. The inner membrane of the mitochondria were almost repaired at 96 hours group. In the group C-1, the nucleus was a little finfluenced by the toxicity of 5-Fu at 24 hours and 48 hours, RER were observed to keep the typical lamella structure of cisternae from 24 to 72 hours group, but inner cavity kept on dilating. In SER, inner cavity were also observed to flatten from 24 to 72 hours group. Mitochondria were always shown normal. All cell organelles were similar to those of normal at 96 hours. Accordingly, it can be said that the treatment of SQ prevents the cytotoxicity of ADM, CP, 5-FU on cell organelles of liver cell and that is concerned with the formation of membrane system of cell organelles.