용접기용 전원장치의 도전손실 저감에 관한 연구

라병훈,고강훈,박성우,김준홍,이현우 경남대학교 신소재연구소 1998 論文集 Vol.10 No.-

본 논문은 용접기용 전원장치의 도전손실 저감에 관하여 제안하고 있다. 최근, 산업용 기기의 전원장치에 많이 적용되고 있는 소프트 스위칭 방식에는 모두가 일장일단이 있다. 대용량의 용접기용 전원장치로 주로 사용되는 기존의 Phsae-Shifted FB DC-DC 컨버터는 고주파 변압기의 동손과 고주파 변압기의 누설에너지와 순환전류의 증가로 인한 1차단의 브릿지의 주 스위칭 소자의 도전손실의 문제점들을 가지고 있다. 이러한 도전손실의 문제점을 보완하기 위하여 본 논문에서는 FB DC-DC 컨버터의 새로운 토폴로지를 제안하고 시뮬레이션하였다. This paper proposed that reducing conduction losses on power supply for welding machine. Recently, all the Soft-Switching method has both merits and demerits. to aadapted industrial machines' power supply. The conventional Phase-Shifted FB DC-DC converter that used power supply for welding machine primarily, have problems that the copper loss in the high frequency transformer and conduction losses of bridge main switching device in the 1st terms, because of the leakage energy in the high frequency transformer and inducing of circulating current. To improved this demarit, this paper suggested and simulated a new topology of Phase-Shifted FB PWM DC-DC converter. - To minimized a circulating current.

말라리아박멸을 위한 조사연구 : 1. 말라리아 유행지역 주민의 항체보유율 변화 1. The study for the malaria eradication 1. The seasonal changes of antibodies of inhabitants lived in malaria epidemic areas

김동수,이형우,조신형,인태숙,이혜정,이욱교,김남렬,신민철,문승욱,임현정,고승연,이종수 국립보건연구원 2000 국립보건원보 Vol.37 No.-

전신 골밀도와 기능 상실 치율 및 하악골 골소주 흡수 양상의 상관 관계

공선애,송용준,노재형,안종인,고영규,김종화,이희철 인제대학교 1996 仁濟醫學 Vol.17 No.1

1993년 3월부터 1995년 6월까지 부산백병원 치과에 내원한 40세 이상 65세 이하의 연령층에 속하는 여성 환자를 대상으로 임상 검사 및 방사선학적 검사를 시행한 결과 치주병에 이환된 치아의 비율이 20% 이하인 30명을 선정하여 이화학적 검사, 치아 파노라마 단층 촬영을 이용한 방사선학적 검사 및 LUNAR DPX 골밀도 측정기를 이용한 전신 골밀도 측정을 시행하였다. 이를 통한 검사 결과를 분석하면서 전신 골밀도 수준과 기능 상실치율 및 하악골 내 골소주의 흡수 양상 간의 상관 관계를 평가하여 다음과 같은 결과를 얻었다. 1.골대사의 지표인 칼슘, 무기인, 알칼리성 인산화효소를 측정하여 전신 골밀도와의 상관 관계를 검증하였으나 유의한 상관 관계는 없었다 (P>0.05). 2.전신 골밀도 분석 결과는 기능 상실치수 및 기능 상실치율에 유의한 상관 관계를 가지고 있었다 (연령에 의한 영향을 보정함)(P=0.0050). 3.30명 환자의 기능 상실치율은 평균 33.7%였으며 치아 파노라마 단층 촬영을 분석한 결과 이공 주변부의 골소주 흡수양상은 현저하여 Diffuse resorption type, Moth-eaten type, Limited(round) resorption type으로 분류 가능하였으나 각 군별로 전신 골밀도 분석 평균의 차이는 없었다(P>0.05). The author selected 30 women whose periodontal disease rate was no more than 20%. They were the patients who have visited at the Dept. of Dentistry in Paik hospital from 1993 to 1995. Biochemical examination, dental panoramic tomogram check and toal body bone density check were done using LUNAR DPX bone densitometer. The results were analysed by total body bone density level, function loss teeth rate and mandibular trabeculi resorption pattern. Then, the author accessed the correlation on the basis of their results. The following observations were made ; 1.Calcium, phosphorus and alkaline phosphatase levels were not correlated with tonal body bone density (P>0.05) 2.There was a good correlation between function loss teeth rate and total body bonedensi ty(corrected by age) (P = 0.0050) 3.We analysed dental panoramic tomograms of 30 women whose periodontal disease rate was no more than 20%. The mean function loss teeth rate in 30 patients was 33.7%. So we could divide mandibular trabeculi resorption pattern into 3-types ; Diffuse resorption type, Moth-eaten type, Limited (round) resorption type. But, there was no correlation between each resorption pattern and total body bonedensity (P>0.05).

兩性界面活劑의 一種인 Dodecyl diamino ethyl glycin hydrochloride의 抗菌作用에 對한 試驗管內 實驗

高春明,張泳鎬,崔大卿 中央醫學社 1967 中央醫學 Vol.12 No.1

The tests for antibacterial and antifungal activities were carried out by using the detergent, Dodecyldiamino ethylglycin hydrochloride and mixture of Dodecyldiamino ethylglycin hydrochloride and Didecylamino ethylglycin hyrdrochloride. 1. The evidence suggests that nonsporeforming bacteria were easily destroyed in lower concentrations (such as 1 percent solution) within 1 to 5 minutes. 2. The evidence concerning sporeforming bacteria has analysed and it were shown being destructed in higher concentrations (1 percent solution) within 5 to 10 minutes. 3. The fungi were likely to have more higher resistances against the drug than those of bacteria. 4. In higher concentration, it was revealed that Myco. tuberculosis has the resistance for a long time respectively.

지하 매설 구조물의 부식과 방식 : 5. 음극방식개론 5. Principle of Cathodic Protection

전경수,고영태,조용범,박경완,이선엽,조성호 한국부식학회 1998 Corrosion Science and Technology Vol.27 No.2

Introductory explanation on cathodic protection(CP) of underground structures is presented. The principle and various types of CP are explained along with the importance of protective coating. Coating reduces the metal surface area exposed to corrosive environment resulting in cut down of the required current for CP. Various field situations which have to be considered during CP design are summarized. Various protection criteria are explained in detail. Emphasis is put on the applicabilty and limit of each criteria in order to help people to select appropriate criteria. Finally, overprotection problem of some metals are explained.

두경피 편평상피암종에서의 P53 단백 발현에 대한 면역 조직화학적 연구

김우형,공선애,이차진,고영규,김종화,이희철 인제대학교 1996 仁濟醫學 Vol.17 No.1

두경부에서 발생하는 편평상피암종은 전체 악성종양 중 2.5∼3.0%를 차지하며 흡연과 음주가 밀접한 관련이 있다고 한다. 구강암을 비롯한 두경부 암종은 현재 증가 추세에 있으며 대개 40代 후반, 우리나라에서는 50代에 호발한다. 두경부 편평상피암종 50례에 대해 p53 단클론 항체(DO-7, DAKO)를 사용하여 p53 단백 발현율을 면역조직화학적으로 검사하여 임상병리학적 인자들과의 상관관계를 분석 하였다. 총 50례중 36례에서 (72.0%) P53 양성 반응을 보였으며, P53 양성 반응과 연령별, 성별, 조직학적 분화도 및 병기와는 상관 관계는 보이지 않았으나 p53 양성 반응과 흡연 및 음주와는 통계학적 유의성을 보였다. 음주와 흡연을 하는 군이 둘다 하지 않는 군에 비해 p53단백 발현율이 2.8배, 흡연만 하는 군에 비해 1.8배로 높아 두경부 편평상피암종에서의 p53유전자 변이로 인한 p53 단백 발현율이 음주 및 흡연을 하는 군에서 의의있게 높았다. 따라서 흡연과 음주를 삼가하는 것이 두경부암을 예방하는 데 중요할 것으로 사료되었다. Squamous cell carcinoma of the head & neck represents approximately 2.5-3.0% of all malignant tumors, and it is known that smoking and drinking is related to high-risk of head and neck squamous cell carcinoma. A total of 50 cases of squamous cell carcinoma of the head & neck regions were studied immunohistochemically to evaluate the expression of p53 protein using p53 monoclonal antibody (Do-7,DAKO) in the relationship with various clinicopathologic factors. Thirty six cases(72.0%) showed positive reaction for p53. There were no significant correlations between p53 expression and age, sex, histopathologic differentiation and clinical TNM stage. But, p53 expression was related to smoking & drinking. Cigarette smokers with alcohol drinking history were 2.8 tomes higher in cancer risk than nonsmokers who abstained from alcohol & 1.8 times higher than smokers who abstained from alcohol. In summary, a history of smoking and alcohol use was associated with higher expression of p53 protein due to p53 gene mutation in squamous cell carcinoma of the head & neck regions. So, abstaining from smoking and alcohol drinking is very important for prevention of squamous cell carcinomas of the head and neck region.

우리나라 製絲用水의 實態 調査

成載千,李鍍,李道洙,高春燮,崔金植,胄元煥 한국잠사학회 1987 한국잠사곤충학회지 Vol.29 No.2

This investigaton was carried cut to obtain the reeling water conditions in Korea. The analyzed items of water were pH, colority, turbidity, acidity, alkalinity, solids electric conductibity hardness and heavy metal ions. About 40% of the reeling water were found to be agreeable, 30% were acceptable provided with some quality control and the others were out of acceptable range mainly based on the M-alkalinity, acidity, pH and total hardness. It was found that there was a following relationship between total hardness and electric conductibity with the relative correlation coefficient r=0.9145. y = 15.967 + 0.22774x Where x, y are electric conductivity and total hardness respectively.

Studies on Cryopreservation of D-shaped and Umbo Larvae of Arkshel1(Scapharca broughtonii)

K.H. Kang,K. H. Kho,Z.T. Chen,Kim Y.H.,Kim J.M. 한국발생생물학회 2003 한국발생생물학회 학술발표대회 Vol.2003 No.1

The present study examined the possibility of cryopreservation of the D-shaped and umbo larvae of arkshell (Scapharca broughtonii), in terms of the survival rates after freezing and thawing. D-shaped and umbo larvae of arkshells were obtained from a shellfish farming on Yosu city. The average shell lengths were m and , respectively. Five cryoprotectants (CPAs), dimethyl sulfoxide (DMSO), glycerol, ethylene glycol (EG), propylene glycol (PG), and methanol, were tested at the concentrations of 1.5, 2.0 and 2.5 M. After larvae suspended in CPAs, cryoprotectants were loaded in 0.5 ml straws at a larval density of 50-100 larvae per straw, and epuilibrated for 10 and 20 minute at room temperature (), repectively. Straws were cooled at a rate of /min from to , held for 5 min at , and then cooled at /min to and equilibrated for 5 min followed by plunging in liquid nitrogen. After storage in liquid nitrogen for 1 day, straws were thawed in a water. As soon as straws were observed to melt, larvae were diluted with an equal volume of ASW and then washed twice with a large volume of ASW at an interval of 2 min to unload the CPAs. The results showed that after equilibration for 10 and 20 minute at room temperature, no larvae survived using methanol as CPAs, and it was observed that larval shells all open slightly, and larval flesh broke down and slopped over the shells. The highest survival rates (D-shaped larvae: 77.6%, umbo larvae: 59.3%) were obtained with 2M DMSO, and 1.5M glycerol yielded survival rates of 53.8% for D-shaped larvae and 37.5% for umbo larvae. The surviving D-shaped larvae showed active rotary motion and perfect membrane integrity and cytoplasmic normality, and the vigorous movement of veliger cilia was observed inside the closed shells. The breakdown of tissue occurred in the abnormal larvae, and the isolated cell often run out of shells.

Cryopreservation of Filefish (Thamnaconus septentrionalis) Sperm

K.H. Kang,Z.T. Chen,K.H. Kho,Z.F. Zhang,Kim J.M.,Kim Y.H. 한국발생생물학회 2003 한국발생생물학회 학술발표대회 Vol.2003 No.1

The present study examined the possibility of long term storage, by cryopreservation in liquid nitrogen, of the sperm of Filefish (Thamnaconus septentrionalis), and the changes in motility, survival rate and ultrastructure of the sperm after freezing and thawing. The sperm was collected by stripping and stored on ice until experiments. For selection of the immobilizing solution, diluted artificial seawater (ASW) of 20, 30 and 40% were tested. The sperm motility was significantly inhibited in 30% ASW, and restored entirely after 100% ASW was added again. Two cryoprotectants, dimethyl sulfoxide (SO) and glycerol, were added to 30% ASW to formulate the extenders at the concentrations between 5 to 20% by volume for freezing. The sperm was diluted at the ratio of 1 :6 with the extenders, inserted into 0.5ml plastic straws and frozen at a freezing rate of /min to after equilibration for 10 min at room temperature, followed by plunging into liquid nitrogen. The straws were thawed in a water bath for 15 sec. The highest post-thawed sperm motility and survival rate were obtained with 5% glycerol Afterward, the effect of different freezing rates was examined using 5% glycerol as a cryoprotectant, and the rate of /min to showed the best result Some ultrastructural changes of sperm, such as the detachment of plasmatic and nuclear membranes, destruction of mitochondria, were observed after cryopreservation. Morphological normality of the sperm in 5% glycerol frozen at the ratio of 1/min to was better than that of others.

KITENIN recruits Dishevelled/PKC δ to form a functional complex and controls the migration and invasiveness of colorectal cancer cells

Kho, D.H.,Bae, J.A.,Lee, J.H.,Cho, H.J.,Cho, S.H.,Lee, J.H.,Seo, Y.-W.,Ahn, K.Y.,Chung, I.J.,Kim, K.K. BMJ PUBLISHING GROUP 2009 Gut Vol.58 No.4