Study on Reliability Improvement of Voltage Transformers by Increasing Voltage Factor

Tae‑Sik Kong,Hee‑Dong Kim,Hung‑Sok Park,Soo‑Hoh Lee,Soon‑Yong Kim,Pil‑Bum Joung,Jin‑Yeub Park 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.3

Voltage transformers (VTs) must be highly reliable as they are essential components of the electric power industry. VT failures can cause a signifcant impact for important facilities such as nuclear power plants. In fact, VTs which passed the international standard, were damaged and sometimes resulted in the shutdown of the nuclear power plants. In order to improve the reliability, VTs with various iron core was studied. The electromagnetic feld simulation, a saturation characteristics test, and an overvoltage breakdown test were conducted. The result shows that the magnetic fux density signifcantly afects the reliability of VTs. To increase the reliability of VTs, it is required to reduce the magnetic fux density by increasing the knee-point and voltage factor. Owing to limited installation space, increasing the size of the iron core is difcult. Instead, VT by decreasing the thickness of the conductor and increasing the number of turns, it was possible to reduce the magnetic fux density without the size change. Therefore, improved VTs were obtained by decreasing the thickness of the conductor and increasing the number of turns, and the improved reliability was verifed through a comparison test with existing VTs. The fabricated VTs shows a signifcantly higher saturation voltage and breakdown time than existing VTs. Thus, by proposed VTs can contribute the stable operation of the nuclear power plant and improve the manufacturer’s quality.

한국산 약용식물의 화장품천연소재로서 응용에 관한연구

안봉전,이진태,이순애,곽재훈,박정미,이진영,박태순,손준호 경산대학교 생명자원개발연구소 2003 생명자원과 산업 Vol.7 No.-

Biological activities and application of sanguisorbae officinalis L. were investigated. In the enzymological physiological activities, the electron donating ability(EDA) was 54.92% in 10 ppm and it was over 90% over 50ppm and SOD-like activity was high as 65.36% in 1000 ppm, it was gradual increased. As inhibitory effect of xanthine oxidase, it was 17.90% in 200 ppm and a little low as 36.89% in 500 ppm and inhibitory effect of tyrosinase, it was a little low as 20.45% below 1000 ppm. As the result of measuring the lipid oxidation, all the concentrations of medical ion treatments had the ability to keep it from acidification and metal ion blocking effects about the lipid oxidation promoting factors(Fe^(2+) and Cu^(2+)), Fe^(2+) was better than Cu^(2+) and all concentrations of medical ion treatments was 40% in 50ppm. When it was applied into normal skin-softener it showed safe effect so that we can expect that as the natural material of cosmetics.

천안지역 일부 다중이용시설의 포름알데히드 농도에 관한 연구

전혜리(Hye-li Jeon),조수연(Su-yeon Jo),조혜란(Hye-ran Jo),조태진(Tae-Jjn Cho),박종안(Jong-an Park),손부순(Bu-soon Son) 대한환경위생공학회 2009 대한환경위생공학회지 Vol.24 No.2

This study was conducted at a Terminal, a Parking Lot, an Underground shopping center, a Funeral hall and a Hospital waiting room of Cheon An area in August 2008 to examine the concentration level of HCHO(formaldehyde). The concentration level of the remodeled sites were 39.4 ± 12.0 ㎍/㎥ in the terminal, 32.7 ± 7.3 ㎍/㎥ in the parking, and 97.8 ± 29.4 ㎍/㎥ in the underground shopping center. The underground shopping center had the highest level and followed by the terminal and the parking. On the contrary, the site remodeling had the level of 17.7 ± 12.4 ㎍/㎥ in the funeral hall and 17.9 ± 0.6 ㎍/㎥ in the hospital waiting room. The funeral hall had highest level than that of the hospital waiting room. Both the remodeled sites and the not remodeled site had concentration level of HCHO below the standard level, but it was higher in the remodeled sites. There were no relations among the HCHO, the temperature and the humidity in facilities of Cheon An area.

용액법에 의한 나노세공 TiO₂의 합성(Ⅰ)

박태순,김호건 한양대학교 이학기술연구소 2006 이학기술논문지 Vol.9 No.-

금속염을 이용한 용액 침전법과 Alkoxide를 이용한 Sol-Gel법에 의하여, 나노세공 TiO₂ 분말을 합성하고 이를 촉매담체로서 사용하기 위해 수열처리를 통하여 물성을 조절하였다. 분말합성시 용액침전법에서는 70℃, 0.55M의 조건으로, Sol-Gel법에서는 실온(25℃)에서 pH 10의 조건으로 합성하였고 반응시간은 3시간으로 동일하게 하였다. 합성된 분말의 수열처리는 80∼200℃에서 3∼24시간동안 진행하였다. 합성된 분말의 결정상 및 미세구조를 확인하기 위하여 XRD, FT-IR, SEM 등의 기기를 사용하였다. TiO₂ powders with nanopores were synthesized via aqueous precipitation methods using metal salts and via Sol-Gel methods using alkoxide. To use these TiO₂ powders as biocatalyst supports, their physical properties were controlled through hydrothermal treatments. In the aqueous precipitation methods, TiO₂ powders were synthesized under the conditions: reaction temperature 70℃, reaction time 3hours and metal salt concentration 0.55M. In the Sol-Gel methods, TiO₂ powders were synthesized under the conditions: reaction temperature 25℃ reaction time 3hours and solution pH10. The conditions for hydrothermal treatment are as following: temperature 80∼200℃ and heat treatment time 3∼24hours. For the charactenzation of the obtained powders, XRD, FT-IR and SEM techniques were used.

체육고등학교 유도선수들의 일반적 특성에 따른 만족도 연구

박순진,윤익선,김태훈 龍仁大學校 武道硏究所 2002 武道硏究所誌 Vol.13 No.1

This study is to investigate and clarify Life and Athletic Satisfaction of Physical Education Highschool Judo Athletes, based on 12 Physical Education Highschool Judo teams that are registered on Korean Judo Federation of Korean Sports Council in 2002. Among the physical Education Highschool Judo teams, 3 male teams and 3 female teams with winning experience over 3 times for 2 years, 2000-2001 and 3 male teams and 3 female teams without winning experience during the same period, and the responses of the 216 persons were applied to analyze actually. This study brings the follow conclusions by using statistical analysis such as reliability analysis, t-test, one-way ANOVA, correlation analysis, regression analysis, etc. First, Life satisfaction in accordance with the background factors depends on school grades and athletic career significantly. Second, Athletic satisfaction in accordance with the background factors depends on athletic career. Third, Life satisfaction in accordance with the background factors shows a positive correlation in winning prize or not(r=.211*), school grades(r=.212*), and athletic career(r=.268*), and a negative correlation between genders(r=-.265*). Also, athletic satisfaction in accordance with the background factors shows a positive correlation in winning prize or not(r=.200*) and athletic career(r=.158*), and a negative correlation between genders(r=.-336*). Forth, In accordance with the background factors school grades(β=.123) and athletic career(β=.217) effect on life satisfaction and the former (β=.-102) and the latter (β=.200) on athletic satisfaction.

큰느타리버섯 인공재배에 있어서 배지조성의 영향

박동철 ; 김순희 ; 강병태 김천대학교 2007 김천대학교 논문집 Vol.28 No.-

This study was performed to investigate on the combinations of optimal medium for the artificial cultivation of Pleurotus eryngii with the various kinds of substrate and nutrient. It was also tested to the mushroom yields and marketable quality of Pleurotus eryngii. Coconut ML. and bean-curd refuses were effective to the mycelial growth, which showed a similar effects compared to a standard medium. a Pine sawdust was more effective than the softened rice hulls and crude rice hulla on the mycelial growth. Elvan as additives was also showed promotive effects on the mycelial growth. In the test of medium weight, optimal weight in about 1400 ml polypropylene (PP) bottle was about 724 gram to 770 gram under 65% humidity. Most suitable periods of incubation were estimated about 40 days. It could be also considered to use TMR(Total mixed Ratio) in the medium combination as nutrients because the TMR addititon of 170 gram weight showed an excellent formation of fruiting body of Pleurotus eryngii. Finally, the optimum composition of nutrients for both yield and quality turned out to be combination of gluten feed( 21.7%), rice polishing (10.2%), wheat bran(52%), soy-hull uncrushed (13.5%) and shell lime (3.6%). Nutritional analysis of the combined nutrients was appeared to have 11.5% humidity, 15.4% crude protein, 4.5% crude fat, 12% crude fiber, 8.2% cash, 1.2% calcium, 0.94% phosphorus, and 55.4% NFE (nitrogen free extract). In the bulk test of artificial cultivation by mushroom farmer, both yield and quality were very excellent to the previous products by harvesting about 200 gram in a PP bottle without a significant deviation.

법랑질 형성부전증 환아의 치험례

박희숙,김태완,김영진,김현정,남순현 大韓小兒齒科學會 2008 大韓小兒齒科學會誌 Vol.35 No.3

Amelogenesis imperfecta is a group of hereditary defects of enamel, unassociated with any other generalized defects. It is classified into 14 subtypes according to different clinical and genetic features. According to its clinical features, it is classified into hypoplastic type, hypocalcified type and hypomaturation type. However, these features tend to co-exist often. Dental features associated with amelogenesis imperfecta include quantitative and qualitative enamel deficiencies, pulpal calcification, root malformations, abnormal eruption, impaction of permanent teeth, progressive resorption of root and crown, congenital missing teeth and anterior and posterior open bite occlusions. The first case patient is a 16 month-old child with discoloration of deciduous teeth. All of her deciduous and permanent dentition has shown amelogenesis imperfecta. The restorational, orthodontic and recent prosthodontic treatments have been completed. Another patient is a 9 year and 3 month-old child with amelogenesis imperfects in both deciduous and permanent dentition. The restoration has been done and the prosthodontic treatment is planned after the completion of growth. Above cases indicate that amelogenesis imperfecta occurs both in deciduous and permanent dentition, and it requires the long term treatment and care. 법랑질 형성부전증(amelogenesis imperfecta)은 전신질환과 관련없이 법랑질에 결함을 나타내는 유전질환이다. 법랑질 형성부전증은 발현되는 증상과 유전 양상에 따라 14가지의 아류형으로 분류된다(Witkop, 1989). 임상적으로는 크게 형성부전형(hypoplastic type), 저석회화형(hypocalcified type), 성숙부전형(hypomaturation type)으로 나누어진다. 하지만 이들은 때로 혼재된 양상으로 나타난다. 법랑질 형성부전증은 법랑질이 질적으로나 양적으르 부족하며 치수 석회화, 치근 형태 이상, 맹출 장애와 영구치의 매복, 점진적인 치근의 흡수, 선천적 치아 결손, 그리고 전치부나 구치부의 개교합 등의 문제점을 나타낸다. 첫 번째 증례는 만 1세 4개월때 유전치부의 치아색 이상을 주소로 내원한 환자로 그 후 모든 유치 및 영구치에서 법랑질 형성부전증이 관찰되어 수복 술식, 교정적 치료 및 최근 보철 치료까지 완료하였다. 두 번째 증례는 만 9세 3매월된 환아로 유치 및 영구치에서 법랑질 형성부전증이 관찰되었다. 수복 치료가 시행되었고 보철 치료는 성장 완료 후 시행하기로 계획하였다. 본 증례들을 통하여 법랑질 형성부전증은 유치 및 영구치 모두에 발생할수 있으며 장기간의 치료 및 관리가 필요하다는 것을 알 수 있었다.

Benzanilide류의 Carbonyl Stretching Frequency에 대한 치환기의 영향(Ⅰ)

박용태,홍순영 경북대학교 1971 生産技術 Vol.5 No.-

The carbonyl stretching frequencies of substituted benzanilides in the solid phase have been determined. Substituents in benzoyl ring give a good correlation with σ^+. This means that direct resoance interaction is significant for the carbonyl streching. The equation ν=12.11σ^++1650.4, was obtained, making it possible to calculate the carbonyl stretching frequencies for benzanilides. Using the σ^+ values for substituents, it was found that the electron transmission ability of benzanilides is twice as great as that of Chalcones.

기능성 Catechol-O-Methyltransferase 유전자 다형성과 한국인 정신분열병의 관련성

박태원,홍영준,박임순,김형섭,최인미,배수영,윤경식,강대희 大韓神經精神醫學會 2001 신경정신의학 Vol.40 No.4

연구목적 : Catechol-O-Methyltransferase(COMT)는 카테콜아민 신경전달물질의 불활성화를 담당하는 효소로서, 정신분열병과 관련된 후보 유전자로서 알려져 왔다. 최근, 기능성 COMT유전자 다형성과 정신분열병의 관련성이 제기되었는데, 한국인 정신분열병에서도 이러한 관련성이 있는지를 살피기 위해 본 연구를 시행하였다. 방 법 : 정신분열병으로 진단된 환자군 103명과 성별 및 연령별로 1:1 짝짓기 대조군 사이에 유전자형과 대립유전자의 분포를 비교하였다. 또한, 환자군은 공격적 행동, 가족력, 아동기 발병 여부에 따라 두 군으로 나누어 비교하였다. DNA의 다형성 부의를 중합효소연쇄반응에 의해 증폭한 후 ,NlaⅢ제한효소법과 전기영동을 실시하여 유전자형을 판별하였다. 결 과 : 환자군 전체와 대조군 사이에 유전자형과 대립유전자 빈도의 차이가 없었다. 가족력이 있는 환자군을 대조군과 비교하였을 때는, 대립유전자 L을 포함하는 유전자형과 그렇지 않은 유전자형의 분포에 있어 유의한 차이를 보였다(p=0.02, OR=3.9, 95% Cl=1.1∼14.3). 결 론 : 한국인 정신분열병과 기능성 COMT 유전자 다형성 사이에 유의한 관련성이 없었다. 따라서, 기능성 COMT 유전자 다형성이 한국인 정신분열병의 발병에 영향을 주지 못한다. 그러나, 정신분열병 가족력과 기능성 COMT유전자 다형성의 관련성이 시시돠어, 향후 본 연구에서 나타난 방법론적인 문제점을 보완하고 추가 대상자를 확보한 연구가 필요하다. Objectives : Catechol-O-methyltransferase(COMT) is involved in the degradation of catecholamine meurotransmitters and has been investigated as a candidate gene in schizophrenia. Recently, possible relationship between functional COMT gene polymorphism and schizophrenia has been suggested. To address the possible role of functional COMT gene polymorphism in the predisposition to schizophrenia, we carried out an association study in Korean schizophrenic patients and controls. Methods : One hundred and three Korean inpatients diagnosed as schizophrenia and 103 age and sex matched controls were selected as study subjects. Patients were subgrouped into two groups on the basis of history of aggressive behavior, family history of schizophrenia and related disorders, and age at onset. We determined COMT genotypes using PCR of the relevant region followed by digestion with NlaⅢ and electrophoresis. Results : No significant differences of allele and genotype frequencies were noted between patients and controls. However, when patients were categorized by the presence of family history of schizophrenia and related disorders, patients with family history showed almost 4 fold higher frequency of having COMT L allele containing genotype compared to controls(p=0.02, OR=3.9, 9.5% CI=1.10-14.33). Conclusion : Although our results do not support an association between functional polymorphism of COMT gene and schizophrenia overall, the findings suggest an association between functional COMT gene polymorphism and familial schizophrenia. Further studies with large samples are needed to confirm this association.

제2형 당뇨병 환자에서 우연히 발견된 기종성 방광염 1례

박보민,김윤정,이영태,노정현,권수경,김동준,고경수,이병두,임경호,이순희,박정현 白中央醫療院 2005 仁濟醫學 Vol.26 No.1

Emphysematous cystitis is an uncommon disease in which bacterias produce gas within the bladder wall and surrounding tissue. Patients with diabetes, neurogenic bladder and chronic urinary tract infection are predisposed to the disease. It is usually caused by E.coli and Klebsiella. Severity of illness ranges from an asymtomatic condition to life threatening cystitis. Succesful management depends on early diagnosis with correction of underlying causes, administration of appropriate antibiotics, establishment of adequate bladder drainage and surgical excision of involved tissue when required. We report a case of 52-year-old woman who did not compain of symtoms of cystitis but epigastric pain, nausea, and vomitting. Emphysematous cystitis was revealed on the abdominal X-ray series incidentally. CT scans of the pelvis showed mottled gas bubble within the bladder. After treatment, the symtoms subsided and plain abdominal film showed no evidence of gas shadow in the pelvic cavity.