점화시기 및 당량비 변화에 따른 CNG기관의 성능 및 배출가스에 관한 연구

한영출,오용석,박봉규,김대열,김미수 한국공작기계학회 2001 한국생산제조학회지 Vol.10 No.4

Research on the development of CNG dedicated en dine that has important meaning both as a clean fuel and an alterna-tive energy to reduce the exhaust emission horn diesel engine are actively going on these days. In this study, in order to present the direction and application of CNG engine, we tested the CNG engine performance experimented by changing the parameters such as ignition timing, equivalent ratio. The engine performance and exhaust emission were measured by engine performance mode at maximum load condition with increasing the rpm in the range of 1,000∼2,200rpm. Also, the testing engine was heavy-duty CNG dedicated engines with displacement of 11,050cc.

맥반석의 물리화학적 특성 : 수안보 맥반석을 중심으로

한오형,정대석 조선대학교 동력자원연구소 1997 動力資源硏究所誌 Vol.19 No.1

The factory wastes, polluted air and water by a industrial development have been contaminated our living environment in the change processing to join the ranks of advenced countries. In order to improve this environment using the Makban-stone which known to be useful in human body, the experiment of mineralogical property survey and heavy metal adsorption is done. Summarized results are as follows : 1. The major minerals of the Makban-stone through microscopic survey and X-ray diffraction analysis are quartz, plagioclase, microcline, amphibole, and biotite : minor minerals are chlorite, epidote, sericite, montmorillonite, and opaque minerals. 2. The Makban-stone is similar to the samples from Japan, according to chemical component survey, and compared with domestic granite, it shows that the content of SiO₂ is low, and the content of Al₂O₃ high. 3. According to the SEM analysis, most of feldspars have so many pores ranging 1∼10μ, and the shape of pores is a cylindrical one ranging 7∼14A˚. The result of an opening volume measurement by particle analysis is shown that the pores have very good structures needed to be adsorpted. 4. Regardless of pH value, it is confirmed that the Makban-stone absorbed heavy metals(Cd^2+, Zn^2+, Pb^2+, Cu^2+, and Cr^6+). 5. The adsorption of heavy metals by the Makban-stone quoted the Freundlich's isotherm equation. A inclination of Pb, Zn, and Cd, by the least-square methods is 0.2, 0.068, and 0.37, but Cr and Cu with inclination more than 2 cannot use for absorbent.

급만성 신장염에 대하여

한대석 대한가정의학회 1984 Korean Journal of Family Medicine Vol.5 No.7

몸이 붓는다-부종

한대석 대한가정의학회 1984 Korean Journal of Family Medicine Vol.5 No.2

3전극형 정전하 중화장치 기초연구

鄭石煥,韓昌陰,李大熙,文在德 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

Methods and systems to remove static electricity are requested necessarily because the static electricity causes a flammable gas explosion, a fire, reduction of production rate in manufacturing semiconductor device and so on. This paper deals with the new structure of electrode to protect dusts attached to the needle electrode previously for controlling the quantities of generated ions and solving the problem of dust attaching to needle electrode. And the discharge system with third electrode was proposed to control the hight and electric field in end of needle electrode. It was possible to control the quantities of generated ion by controlling electric field in needle electrode. This showed the possibilities to solve the nonequilibrium of generated ions when using the ac power source.

精神科 入院의 季節的 變動

吳碩煥,朴助烈,裵大均,金錫柱,韓東大,張貞富,柳志珍 大韓神經精神醫學會 1964 신경정신의학 Vol.3 No.2

(1) Authors studied seasonal fluctuation of psychiatric admission preliminarily, based on data of admission to Pusan area for a 4 year period of 1960-1963, and obtained following impressions. (2) The rate of admission in Pusan area and its seasonal fluctuation appear quite similar to those reported by investigators for European, American and Japanese cities. Thus the admission increases in spring and reaches the maximum in May and then gradually decreases toward the end of year. (3) The data obtained by statistical analysis of the seasonal fluctuation in Pusan area were compared with those of foreign ones in order to observe how to be related to the latitude of the locality. It is the general tendency that the lower latitude showed increase of admission in earlier months of the year than the higher latitude did. (4) It is a impression that the admission of affective psychoses are more sensitive to the climatic factors than the schizophrenics. (5) It is conjured by the authors that the socio-cultural and economic factors should be considered to give an account of the seasonal fluctuation of psychiatric admission.

조명광원의 색온도와 조도 및 스펙트럼 측정

최대욱,박성진,임춘우,석성수,오철한 慶北大學校 師範大學 科學敎育硏究所 1999 科學敎育硏究誌 Vol.23 No.-

The peak wavelength and temperatures of W-Halogen standard light source were measured by using the modified Wien's Law. In the case of graybody, the emissivity ε should be taken into account in using the Wien's Law. In the experiment, PDA spectroscope was used for the measurement of peak wavelength of intensity distribution of spectrum. As the current of light source increases from 5A to 7.4A, the peak wavelength of intensity distribution of the spectrum decreased from 717nm to 690nm, and temperature increased from 3127K to 3330K. Illuminations of three-wavelength lamps and light source were also measured. It was found that irradiation spectrum of those three-wavelength lamps are not coincident to blue(450nm), green(550nm) and red(610nm).

초음파 주파수와 음향밀도에 따른 하수슬러지 전처리 특성

김대용,정연화,김한석,정진희,성낙창 東亞大學校 建設技術硏究所 2008 硏究論文集 Vol.31 No.2

The objective of this study was to investigated the pretreatment characteristics of sewage sludge by ultrasonic process. Excess sewage sludge was sampled from N sewage treatment plant (STP) in B city. The ultrasonic processor was designed to operate with 28 kHz and 40 kHz,independently. During sonication experiment, sludge samples were stirred by agitator. The acoustic densities were changed 33 to 139 W/L by control of current strength. The sonication time was in the range of 10 min and 40 min. The total chemical oxygen demand (TCOD) and soluble chemical oxygen demand (SCOD) of sludge were analyzed with K2Cr207 Closed Reflux Method. The results showed that sonication with 28 kHz of acoustic frequency is better than sonication of 40 kHz in incensement of SCOD/TCOD ratio. Also, the sludge solubilization rates increased as the sonication time and acoustic density increased. The application of dual frequency sonication for sludge pretreatment can be interest for sewage treatment plants having problems in sludge treatment and disposal.

IDI형 정적연소기에서의 연락공각도가 연소특성, 및 열유속에 미치는 영향

김시범,윤수한,이상석,하종률,전대수 東亞大學校 大學院 1998 大學院論文集 Vol.23 No.-

We use the IDI type constant volume which is applied Indirect Injection strafied charge method to solve the problems of lean-burn such as misfire and cycle-variation. There are many factors to effect on the combustion charateristics in indirect injection strafied engine. The passagehole angle is the most important factor in that determine the direction of inflowed fuel and flame to the main chamber. In this study, we measured combustion pressure and wall temperature to examine the combustion characteristics and heat flux with the passagehole angle in the main chamber.

말기 신부전 환자에서 투여 경로에 따른 유전자 재조합 인 Erythropoietin(Epokine^(�))의 효과와 안정성에 대한 연구 : 제 4상 연구 A Phase 4 Single Center Study

송현용,윤향숙,강신욱,최규헌,하성규,이호영,한대석 대한신장학회 2002 Kidney Research and Clinical Practice Vol.21 No.2

목 적 : 국내 독자적 기술로 첫 개발된 유전자 재조합 인 에리트로포에틴(Epokineⓡ)의 투여방법에 따른 유효성과 안정성을 알아보고자 하였다. 방 법 : Epokineⓡ을 주당 100-150 U/kg, 주 2회, 12주간 피하 주사하여 목표 또는 안정된 혈색소치 유지 후 무작위로 피하 및 정맥 주사군으로 나누어 12주간 혈액투석 및 복막투석 환자13명, 28명에서 유효성, 안정성을 분석하였다. 결 과 : 양군에서 혈색소치와 헤마토크릿은 Epokineⓡ 투여 2주 후부터 증가, 혈색소치가 혈액투석 환자는 투여 전 7.3 g/dL, 투여 12주 9.5 g/dL, 24주 10.6 g/dL로, 복막투석 환자는 6.8g/dL에서 12주 10.2 g/dL, 24주 10.8 g/dL로 증가하였다. 양군에서 교정 망상적혈구수(%)는투여 1주 후부터 전 기간동안 증가하였다. 혈청 내 철분, ferritin치는 양군에서 투여 2주 후부터감소, 총 철분 결합능은 투여 2주 후부터 증가하였다. 12주째 혈액투석 환자에서 많은 Epokineⓡ용량이 필요했으나(142.2±20.5 vs 117.3±33.6 U/kg/wk, p<0.001) 24주 후 양군의 용량차이는 없었다(123.6±41.5 vs 99.2±49.3 U/kg/wk, p>0.05). 혈액투석 환자에서 피하 주사가Epokineⓡ 투여용량이 더 적었으나(97.4±15.4 vs 145.4±2.9 U/kg/wk, p<0.002) 복막투석 환자는 차이가 없었다(93.0±60.2 vs 105.4±9.7 U/kg/wk, p>0.05) 연구기간 중 9명(18.8%)에서혈압강하제 추가가 필요한 혈압상승, 근육통 동반 상기도 감염 유사증상 및 두통 등의 부작용이 있었다. 대부분 자연소실 혹은 대증요법으로 치유되었고 2명이 부작용으로 탈락하였다. 결 론 : 말기 신부전 환자의 빈혈 개선에 사용하는 Epokineⓡ의 효과는 복막투석 환자에서 더 좋았으며 투여 경로는 정맥주사보다 피하주사가 높음을 알 수 있었다. Background : We evaluated the clinical efficacy and safety of recombinant human erythropoietin(Epokine^(ⓡ)). Methods : A comparative prospective study of intravenously and subcutaneously administrated Epokine^(ⓡ) conducted 13 patients performing hemodialysis and 28 patients performing continuous ambulatory peritoneal dialysis with end-stage renal disease. Epokine^(ⓡ) was given initially at a dosage of 100 unit/kg, subcutaneously, two times a week. The patients had achieved stable or more than 10 g/dL of hemoglobin level for 12 weeks and then we randomized switching intravenously or subcutaneously administrated Epokine^(ⓡ) for another 12 weeks. Results : Hemoglobin(g/dL) and hematocrit(%) increased significantly from baseline levels beginning from 2 weeks after Epokine^(ⓡ) administration. In HD patients, hemoglobin increased significantly from 7.3 to 9.5 after 12 weeks and to 10.6 after 24 weeks. In CAPD patients, hemoglobin increased significantly from 6.8 to 10.2 after 12 weeks and then 10.8 after 24 weeks(p<0.05). Corrected reticulocyte count(%) was significantly increased from baseline levels beginning from 1 week after Epokine^(ⓡ) administration and continuously increased during study period in both group. Serum ferritin and serum iron decreased significantly and total iron binding capacity increased significantly after 2 weeks. At 12 weeks, HD patients were significantly needed more dosage of Epokine^(ⓡ) than CAPD patients(142.2±20.5 vs 117.3±33.6 U/kg/wk, p<0.001), but at 24 weeks, the dosage was not different(123.6±41.5 vs 99.2±49.3 U/kg/wk, p> 0.05). In HD patients, intravenously administrated Epokine^(ⓡ) group was more dosage than subcutaneously group(97.4±15.4 vs 145.4±2.9 U/kg/wk, p< 0.002), but CAPD patients were not different by administration method(93.0±60.2 vs 105.4±9.7 U/kg/ wk, p>0.05). The 9 cases(18.8%) were suffered from headache and flu-like syndrome, but these side effects were not severe and disappeared from conventional therapy. Conclusion : Epokine^(ⓡ) administration is safe and effective in treating anemia of ESRD patients and subcutaneously administration is significantly more effective than intravenously. (Korean J Nephrol 2002;21(2):190-198)