• Transactions of the Korean hydrogen and new energy society
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• v.5 no.2
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• pp.91-98
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• 1994

In this study hydrogen gas and oxygen gas are used to make a pollution-free engine which is a closed system with the components such as a combustor, two turbines, a radiator and a compressor. One of the two turbines produces main power, and the other is used to drive a compressor to compress unburned gases and to return them to the combustor. Some of the water from the radiator is pumped to cool down the internal wall of the combustor and to be used as a working fluid which expands from liquid state to vapor state to get more expansion work. The possibility of operating the whole system is checked by the thermodynamic analysis to make the closed engine system. The calculations in the thermal analysis are based on the Brayton cycle and the Rankine cycle. The closed system in this study shows similar efficiency as usual internal combustion engines, but it produces water only without air pollution such as $NO_x$ and soot.

• Advances in pediatric surgery
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• v.1 no.2
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• pp.177-180
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• 1995

A 2-day-old male (Premie, Large for gestational age(LGA), Intrauterine period(IUP) 33 weeks, birth weight 2,955 gram) was transferred with marked abdominal distention, bilious return via the orogastric tube, respiratory difficulty, and generalized edema (hydrops fetalis). He was born by cesarean section to a 36 year-old mother. Antenatal ultrasonogram at IUP 31 weeks demonstrated multiple dilated bowel loops suggestive of intestinal obstruction. There was no family history of cystic fibrosis. Simple abdominal films disclosed diffuse haziness and suspicious fine calcifications in the right lower quadrant. Barium enema demonstrated a microcolon. Sweat chloride test was not available in our institution. At laparotomy, there noted 1) a segmental volvulus of the small bowel with gangrenous change, associated with meconium peritonitis, 2) an atresia of the ileum at the base of the volvulus, and 3) the terminal ileum distal to the volvulus was narrow and impacted with rabbit pellets-like thick meconium. These findings appeared to be very similar to those of a complicated meconium ileus. In summary, the ileal atresia and meconium peritonitis seemed to be caused by antenatal segmental volvulus of the small intestine in a patient with probable meconeum ileus.

• Applied Chemistry for Engineering
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• v.5 no.5
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• pp.795-800
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• 1994

The detergencies of these new functional anionic surfactants, sodium monoglycerol ${\alpha}$-sulfonated alkanoates, were investigated and compared with those of two commercial surfactants, that is, sodium ${\alpha}$-sulfonated alkanoic acid methyl ester and sodium alkyl benzene sulfonate. According to the variation of the hydrophobic alkyl chain length, the order of detergency was shown to be $C_{16}$>$C_{18}$>$C_{14}$>$C_{12}$. From the comparision experiment for the detergency and the various fundamental properties of two other surfactants, it was found that sodium monoglycerol ${\alpha}$-sulfonated hexadecanonate has the most outstanding characteristics of detergency. Possibly this result shows light on its industrial application as a nonpolluting detergent.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.7
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• pp.799-804
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• 2014

To combine to the power transmission, photovoltaic inverter is demanded, because the photovoltaic system is generated direct current power. However, photovoltaic inverter is sensitive to high temperature. In the temperature rising such as at noon and on summer, efficiency of machine is decreased due to the loss increment. Because this problem causes national energy loss according to the expanding the photovoltaic industry, countermeasure is demanded. There, in this paper, we installed a cooling system using a thermoelement regardless of the temperature. Also, we analyze the cooling effect according to the position of two fans which improve the effect maximize.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.856-856
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• 2009

석유 및 천연가스를 대체하는 자원으로 석탄이 유망하다고 전망하고 있다. 미국에서는 6대 파괴력이 있는 기술로 청정석탄기술이 선정되었고, 한국에서도 15대 그린에너지 중 하나인 청정연료에 석탄전환기술이 포함되어 전략로드맵이 작성되고 있다. 국내에서 추진되고 있는 석탄기술은 석탄가스화를 기반으로 하고 있다. 석탄가스화는 고체연료인 석탄을 $1000^{\circ}C$ 이상의 고온에서 산소와 반응시켜 일산화탄소와 수소가 주성분인 합성가스로 전환하는 기술이다. 석탄을 가스화하면 석탄에 포함된 불순물을 쉽고 완벽하게 제거할 수 있으며 특히 CO2 제거를 값싸게 할 수 있어 청정화가 가능하다. 최근 고유가를 겪으면서 열량이 높은 고급탄의 확보가 어려워지면서 가격이 낮고 수급이 용이한 저급탄을 활용하는 기술의 수요가 발생되어 국내에서 기업을 중심으로 저급탄을 고효율로 가스화하는 기술 개발이 시도되고 있다. 정제된 석탄가스는 성분을 조절하여 촉매에 의해 메탄으로 전환시킬 수 있고, 이렇게 제조된 가스를 합성천연가스(SNG)라 한다. 값싼 저급탄을 사용하면 SNG를 천연가스보다 저렴하게 생산할 수 있다. 국내 기업이 SNG 제조 실증시설을 도입하고, 동시에 핵심기술인 SNG 합성반응공정을 개발하는 사업을 추진하고 있다. 석탄가스를 촉매반응에 의해 디젤 및 �F싸로 전환하는 석탄간접액화기술은 현재 남아공 Sasol사에서 상업적으로 운전되고 있는 기술이나 국내로의 기술이전이 거의 불가능하다. 철을 기반으로 하는 고유 촉매와 scale-up이 가능한 반응기가 핵심인 기술로 국내에서 세미-파일럿급 액화공정 기술개발이 진행중이다. 전세계적으로 석탄액화공장의 수요가 현재의 15만배럴/일에서 2030년 240만배럴/일로 증가한다고 예측된다. 따라서 200조원 이상의 플랜트 시장이 기대되며 국산 가스화, SNG 및 액화기술로 상당부분의 시장을 장악하고자 한다.

• The Inventors News
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• no.45
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• pp.1-16
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• 2006

'2006 여성발명 창의교실' 첫 수료식 개최/2006 대한민국 여성발명품 박람회/제12회 여성발명 우수사례 발표회/신세대 인터넷 용어, 상표 출원 증가/독창성가진 화투, 특허품으로 인정/대학 강의실에도 특허 열풍 분다/차세대 분자전자 메모리 특허 증가/교통카드 특허 이용료 협상 골머리/국제지식재산연수원, WIPO 공식 연수기관 지정/PCT, 국내단계 진입기간 31개월까지로 연장/직무발명 보상에 대한 길 더 넓어져/특허.실용신안, 권리 강화 되다/'특허행정체험단' 통해 고객 감동 실현/신규 발명교실 설치 계획 안내/사랑 확인해 주는 '연인의 잔' 발명/'무공해 플라스틱'으로 환경 사랑 나선다/중국, R&D 기지로 급부상하다/특허출원 실적, 대학별 빈부 격차 심해져/삼성,SDI,OLED 특허 출원 세계 최다/한국여성발명협회, 홈페이지 전면 개편/특허청, 국방과학연구소와 업무협력협정 체결/브랜드 경영 열풍, 지자체에도 분다/'DMB 기술표준과 전략적 특허분석' 발간/지렁이로 화장품, 비누 발명/건강 상식/시중 은행, 월드컵 미끼상품 못판다/역사 속의 발명품/하루 10문 발명교실/특허Q&A/조정숙 코코허브 대표/수원 매현중학교 발명교실/파마머리 발명, 올해로 1백주년/아이디어 착상 및 발명 기법/창의성은 우리의 밥줄이다/야마모토의 추잉껌/PSP진동기술 특허소송 소니패배/내셔널반도체, 특허 장난꾼 잡는다/특허청, '제7회 반도체 설계 공모전' 개최/KAIST 학생들, 특허청에서 '연구노트' 작성법 전수/특허법원, 전국법원 중 처음으로 구술변론 도입/한국여성발명협회 회원사 발명품 가이드/'2006 전국 발명표어 공모대회' 공고

• Advances in pediatric surgery
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• v.1 no.1
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• pp.27-32
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• 1995

Jejunal and ileal atresias are the most common cause of congenital intestinal obstruction and accounts for about 1/3 of all cases of intestinal obstruction in newborns. Despite the relative frequency of this anomaly, its survival rate was less than 10% up to 1950, more recently the survival rate has risen rapidly to 90% with the introduction of modern surgical techniques and the use of total parenteral nutrition. In 1969 Thomas described a tapering jejunoplasty to manage the discrepancy in the size of the proximal dilated lumen & contracted distal lumen, and to preserve absorptive surface when the dilated jejunum involved a long length, and Grosfeld et al.(1979) facilitated this method by using GIA staplers. Author have also used GIA stapler to resect the antimesenteric portion of the dilated proximal bowel in 8 cases of jejunoileal atresias with good results. The following results were obtained ; 1. There we 3 jejunal atresias & 5 ileal atresias, and male to female sex ratio was 5 : 3. 2. The type of atresia was as follows ; type IIIa was 3 cases, type IIIb was 4 cases, type IIIb+IV was 1 case. 3. In non-complication cases(5 cases), the mean hospital day was 16 days, and oral feeding was feasible from 6.2 days after operation. 4. The complications(anastomotic leakage, pneumonia) were frequently occurred in type IIIb cases and in low birth weight cases(75%). 5. Mortality rate was 25% including DAMA(discharge against medical advice) discharge case.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.165-168
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• 2008

This study performed the 3-dimensional inspection analysis for cavitation by using the ultrasonic pulse velocity method to detect detailed various cavitations in a concrete test material. The internal-void are made of non-void test material and two types of which a regular square type and a rectangle type that produced through the 3-dimensional cavitation to put into a $500{\ast}500{\ast}500mm$ sized non-reinforced concrete test material. The tomography method for the ultrasonic pulse velocity method was used for the non-destructive test. As a result, this study has found that it is possible to visualize the cavitation as an image, and to analyze the internal-void in detail by the non-destructive method.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.85-86
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• 2010

This study is aimed to investigate on the structural properties (like as strength, failure mode, ductility) of beams with web openings reinforced with steel tube of square. The main parameters are follows; 1) with and without web opening 2) the number of opening, 3) location of openings. In the quasi-static tests, structural properties of PFBS1A and PFBS2A were most superior. When the locations of opening are respectively maximal moment zone (M), shear (S), co-existence area of moment and shear (M+S), the specimen with web opening at maximal moment zone is not less than that without web opening in terms of strength and ductility.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.6
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• pp.344-350
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• 2019

In this study, waves2Foam implemented in OpenFOAM is used to simulate numerically the wave pressure on a verical caisson under the condition of with and without the placement of Tetrapods in front of the caisson. The comparisons of the numerical results and the experimental data show fairly good agreement between them. Based on this, it is possible to suggest an optimal combination of coefficients for an empirical formula to represent the protective TTP layer as porous media.