토출압력 (吐出壓力) 및 호오스길이가 도달성에 미치는 영향에 관한 연구

권순홍,최규홍 ( Soon Hong Kwon,Kyu Hong Choi ) 한국농업기계학회 1982 바이오시스템공학 Vol.7 No.2

말초혈액 단핵구 세포에서 IL-1β에 의한 OPG/OCIF mRNA 발현 조절에 관한 연구

최규홍,정미선,오한진,김선우,윤현구,한인권,장학철,임창훈,정호연,한기옥,강영순,문인걸,황창선,김윤이,김의현 대한내분비학회 2000 Endocrinology and metabolism Vol.15 No.2

Background : Osteoprotegerin(OPG) is a soluble member of the tumor necrosis factor(TNF) receptor family and inhibits osteoclastogenesis by interrupting the cell-to-cell interaction between osteoblastic/stromal cells and osteoclast progenitors. OPG is expressed in many tissues including osteoblasts and may act on bone tissues in a paracrine and/or autocrine fashion. Futhermore, many cytokines and growth factors are known to influence the regulation of OPG expression in osteoblastic/stromal cells. The aims of the present study were to examine whether or not OPG was expressed in human peripheral blood mononuclear cells(PBMCs) and to investigate the effects of IL-1?, which were known as potent osteotropic agents, on the regulation of OPG mRNA in PBMCs. Methods : PBMCs were isolated by centrifugation over Ficoll-Hypaque density gradients from postmenopausal women and cultured in 6-well plates containing ?-MEM supplemented with 5% FBS. The expression of OPG mRNA in PBMCs was observed by RT-PCR in adherent and nadherent cells on culture plates. To observe the effect of OPG expression by IL-1?, we measured the concentration of OPG mRNA by altering the concentration and incubation time of IL-1?. The measurement of OPG mRNA was done by semi-quantitative PCR and indicated as OPG/GAPDH. Results : OPG was expressed both in cells attached to the surface of culture plates and in non-adherent cells for the incubation of peripheral blood mononuclear cells. The effect of OPG mRNA by IL-1? tend to increase in accordance with the length of incubation time and maximizes at 12 hours of incubation time and shows 1.2?3.5 times higher than the standard level at the concentration of 0.5ng/ml. However, the increased quantity in concentration varies according to individuals. Conclusion : OPG mRNA is expressed in peripheral blood mononuclear cells and known to be increased by IL-1?(J Kor Soc Endocrinol 15:204-213, 2000).

農業機械 主要部品의 機械的 性質에 關한 硏究(Ⅰ)

崔圭洪,權純洪 建國大學校 附設 農業資源開發硏究所 1991 農資源開發論集 Vol.16 No.-

본 실험은 農業機械의 性能 및 耐久性에 밀접한 관계를 가지며, 素材의 品質面에서 구성하고 있는 化學成分이 韓國工業規格에 적합치 못한 주요 부품의 材料에 대한 機械的 性質을 조사하여 良質素材의 安定供給을 위한 素材産業의 육성과 이에 따른 優良農業機械의 生産供給으로 素材에 의한 品質低下 要因이 발생하지 않도록 그 基本資料를 제시하고자 실시하였으며, 분석한 결과를 요약하면 다음과 같다. 1) 一般鋼材 및 特殊用鐵鋼을 材料로 사용하는 부품은 素材別로 機械的 性質이 좋지 못한 것으로 나타났다. 2) 鑄物類를 素材로 하고 있는 부품은 모두 저급의 材質을 사용하고 있는 것으로 나타났다. 3) 小規模 群小業體가 生産供給하는 機種의 부품에 사용되고 있는 재료는 대단히 불량한 것으로 나타나 이에 대한 素材의 品質向上 및 良質素材의 安定供給을 위한 素材産業의 육성이 절실한 것으로 생각된다. These studies were carried out to investigate the mechanical properties for the major part in agricultural machinery in order to bring up the material industry and for the factor of quality drop not to happen to Korean farm machinery. The results are as follows ; 1) Carbons Steels and special purpose steels used in the major parts in agricultural machinery were inferior materials in mechanical properties. 2) Alloy castings used in the major parts were unsuitable to mechanical properties. 3) The attachments for working machinery, power sprayer, thresher, straw cutter, which were manufactured by small makers, were not suitable to the major parts in agricultural machinery. I think that urgent problems are the improvement of quality control in materials and the upbringing of the material industry in order to stabilize the supply of good quality materials in Korean farm machinery.

임펠러의 外經, 날개매수 및 날개 曲率半經이 口經 80mm 農用揚水機의 性能에 미치는 影響

崔圭洪,權純洪 建國大學校附設農業資源開發硏究所 1986 農資源開發論集 Vol.11 No.-

Discharge, total head, power requirement, and pump efficiency were measured in accordance with the different outside diameter, the different number of blades and the different radius of curvature in the impeller to obtain data for economical pumping operation in Korean agricultural 80 mm diameter pump. The results obtained are summarized as follows; 1. Discharge and power requirement increased in proportion to outside diameter of impeller increased, but there was almost no influence in total head. 2. Total head and power requirement increased in proportion to number of blades increased, but there was almost no influence in discharge. 3. Total head and power requirement increased inproportion to radius of curvature increased, but there was almost no influnce in discharge. I think that radius of curvature is factor to most influence in agricultural pump efficiency. 4. In the agricultral 80 mm pump, pump efficiency increased as impeller revolution decreased, but could not reach to the max. range of specific disharge, and discharge was ower the max. range of specific discharge in the insured revolution, but pump efficiency was low. 5. In the impeller design, I thought that the manufactures did not follow the method for making the radius of curvature was based on the blade exit angle of hight efficiency and calculating the inside diameter, outside diameter, number of blades blade inlet angle as requirement discharge.

吐出壓力 및 호스 감김길이가 噴霧性能에 미치는 影響에 關한 硏究

崔圭洪,權純洪,李承奇 建國大學校附設農業資源開發硏究所 1988 農資源開發論集 Vol.13 No.-

Suction rate, discharge rate, overflow rate, power requirement were measured in accordance with the different hose rolling length using 3 hole swath type nozzle to investigate the effect affecting the spray performance of power spreyer. The results are summarized as follows; 1. Suction rate was uniformed in proportion to pressure increased. 2. Discharge rate and power requirement increased in proportion to pressure increased, but overflow rate decreased. 3. Suction rate, discharge rate, overflow rate, and power requirenment showed in order type 70, type 60, type 40. 4. The pressure drop was an equivalent of 6% in 100m-rolling length of hose, and it was an equivalent of 10% in 200m-rooling length of hose.

吸入호오스의 口徑 및 임펠러 回轉數가 農用楊水機의 性能에 미치는 影響

崔圭洪,權純洪 建國大學校附設農業資源開發硏究所 1985 農資源開發論集 Vol.10 No.-

Discharge, total head, power requirement, and pump efficieney were measured in accordance with the different diameter of suction hose and the dofferent revolution of impeller to obtain data for economical pumping operation in Korean agricultural pump. The results obtained are summarized as follows; 1. Compared to the 80 ?? diameter hose, total head with discharge decreased about 0.3-0.4m in the 75 ?? diameter hose and increased about 0.2-0.3m in the 90 ?? diameter hose at the at the range of specific discharge 0.45-0.90㎥/min. 2. Power requirement with discharge was about 0.15-0.2ps higher in the 90 ?? diameter hose than 80 ?? diameter hose. However, there was almost no difference in the 75 ?? diameter hose. 3. Pump efficiency decreased about 2-3% in the 75 ?? diameter hose compared to the 80 ?? diameter hose at the range of specific discharge. However, there was almost no difference in the 90 ?? diameter hose. 4. Using the 75 ?? diameter hose to 80 ?? pump cause the loss of head and efficiency, and it is considered disadvantageous to use the 90 ?? diameter hose in the economical aspect. 5. In the 80 ?? pump, discharge, total head, and power requirement increased and pump efficiency decreased as impeller revolution increased. 6. The 80 ?? pump manufactured in Korea showed high efficiency around about 1,000rpm, but could not reach to the max. renge of specific discharge 0.90㎥/min, and discharge was over the max. range of specific discharge in the insured revolution with manufacturer, but the pump efficiency was low. It is because that the manufacturer did not follow the method for determining the revolution of highest efficiency from the compared revolution test after deciding the shape of impeller and labeled the insured revolution by the determination of optional revolution.