태권도선수의 운동 상해요인과 대처방안에 관한 연구

최춘길,하웅의 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.1

The purpose of this study was to investigate the variables relating to the incidence and copying strategies of taekwondo athletic injury. The subjects were taekwnondo athletic(n=40) from K university. In The method of this study, athletic injury questionnaire was designed for the purpose of this study researcher. The selected variables relating to the incidence of athletic injury of this study were training game process variable, game boundary. The conclusions and implications of this study were as follows : The variables relating to the injure incidence of taekwondo player were lack of skill and strategy(47.5%), training too hard(42.5%), lack of basis physical ability(35%) in training, game process variables, physical fatigue(77.5%), indifference of warm-up, cooling down (62.5%), individual mistake(30%). In boundary variables were exceed tention(32.5%), lack of self-confidence(30%), high anxiety(25%).

다점식 피토관의 효율적인 교정에 대한 연구

전세종(Sejong Chun),최용문(Yong Moon Choi),최해만(Hae Man Choi),최지철(Ji Chul Choi),홍경기(Kyung Ki Hong),한상우(Sang Woo Han),김웅선(Woong Sun Kim) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.6

The averaging pitot tube or annubar is widely employed to measure the flow rate of the pollutants discharged from the chimney in many industrial situations. Accurate monitoring of the amount of the discharged pollutants necessitates the annubar calibration, which is usually performed in wind tunnels and the calibration conditions are dependent on the size of the wind tunnel test section. However, there are many situations where annubars are larger than the typical size of wind tunnel test sections. In the present study, a new technique using partial blockage was proposed, enabling calibrations of large annubars in various configurations. The results demonstrated favorable agreements with the original annubar coefficients.

SFN 및 OCR 배치시 간섭에 관한 연구

최성웅(Sung-Woong Choi),이용우(Yong-Woo Lee),최상성(Sang-Sung Choi),하천수(Chun-Soo Ha),오우진(Woo-Jin Oh) 대한전자공학회 2002 대한전자공학회 학술대회 Vol.2002 No.11

헤밍 공정의 횟수가 헤밍 품질에 미치는 영향에 관한 연구

신나은,최문호,최영덕,최해운,장래성,최계광,김세환,윤재웅,이춘규,Shin, Na-Eun,Choi, Moon-Ho,Choi, Young-Deok,Choi, Hae-Un,Jang, Rae-Seong,Choi, Kye-Kwang,Kim, Sei-Hwan,Yun, Jae-Woong,Lee, Chun-Kyu 한국금형공학회 2016 한국금형공학회지 Vol.10 No.1

In this study, it was investigated by comparing the experimental hemming by the 3 steps and 2 steps in order to stabilize the quality of the hemming process. In the experimental results, the three-step hemming superior to the two-step one and the dimensional stability of part that was made by the three-step on was high. When the second stage Hemming has been found that the deflection caused by the force to the wear of the punch becomes larger plane can be folded by the hemming crimping and crimp uncertain.

Heterolayered, One-Dimensional Nanobuilding Block Mat Batteries

Choi, Keun-Ho,Cho, Sung-Ju,Chun, Sang-Jin,Yoo, Jong Tae,Lee, Chang Kee,Kim, Woong,Wu, Qinglin,Park, Sang-Bum,Choi, Don-Ha,Lee, Sun-Young,Lee, Sang-Young American Chemical Society 2014 NANO LETTERS Vol.14 No.10

<P>The rapidly approaching smart/wearable energy era necessitates advanced rechargeable power sources with reliable electrochemical properties and versatile form factors. Here, as a unique and promising energy storage system to address this issue, we demonstrate a new class of heterolayered, one-dimensional (1D) nanobuilding block mat (<I>h</I>-nanomat) battery based on unitized separator/electrode assembly (SEA) architecture. The unitized SEAs consist of wood cellulose nanofibril (CNF) separator membranes and metallic current collector-/polymeric binder-free electrodes comprising solely single-walled carbon nanotube (SWNT)-netted electrode active materials (LiFePO<SUB>4</SUB> (cathode) and Li<SUB>4</SUB>Ti<SUB>5</SUB>O<SUB>12</SUB> (anode) powders are chosen as model systems to explore the proof of concept for <I>h</I>-nanomat batteries). The nanoporous CNF separator plays a critical role in securing the tightly interlocked electrode–separator interface. The SWNTs in the SEAs exhibit multifunctional roles as electron conductive additives, binders, current collectors and also non-Faradaic active materials. This structural/physicochemical uniqueness of the SEAs allows significant improvements in the mass loading of electrode active materials, electron transport pathways, electrolyte accessibility and misalignment-proof of separator/electrode interface. As a result, the <I>h</I>-nanomat batteries, which are easily fabricated by stacking anode SEA and cathode SEA, provide unprecedented advances in the electrochemical performance, shape flexibility and safety tolerance far beyond those achievable with conventional battery technologies. We anticipate that the <I>h</I>-nanomat batteries will open 1D nanobuilding block-driven new architectural design/opportunity for development of next-generation energy storage systems.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2014/nalefd.2014.14.issue-10/nl5024029/production/images/medium/nl-2014-024029_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl5024029'>ACS Electronic Supporting Info</A></P>

Kluyveromyces fragilis 의 β- Galactosidase(Lactozym) 에 의한 유당의 가수분해중 소당류의 생성

최춘언,박성준,문지웅,허경택,유제현,김현위 한국낙농학회 1989 韓國酪農學會誌 Vol.11 No.4

본 연구는 Kluyveromyces fragilis의 β-galactosidase(Lactozym^R)에 의하여 유당의 가수분해중에 생성되는 소당류에 대하여 조사하였으며, 그 결과는 다음과 같다. 32%의 유당 농도에서 全糖 中 37%의 소당류가 생성되었으며, 全糖 中의 단당의 농도가 51∼58%이었을 때 소당류의 생성은 최고치에 달하였다. 9종류의 소당류가 활성탄-celite chromatography의 40% 에탄올 획분에서 분리되었다. 유당의 가수분해물로부터 분리된 3종류의 소당류의 화학구조는 galactosyl-β-(1→6)-glucose, galactosyl-β-(1→6)-galactose, galactosyl-β-(1→6)-galactosyl-β-(1→4)-glucose로 동정되었다. Formation of oligosaccharides during hydrolysis of lactose with Kluyveromyes fragilis β-galactosidase (Lactozym^R) was investigated at different lactose concentrations. At 32% lactose concentration, 37% of the total sugar was converted to oligosaccharides. When 51-58% of the total sugar was hydrolyzed to monosaccharides, the amount of oligosaccharides reached maximum Nine oligosaccharides were separated using charcoal celite chromatography at 40% ethanol fraction. The chemical structure of three oligosaccharides isolated from lactose hydrolyzates were identified as galactosyl-β-(1→6)-glucose, galactosyl-β-(1→6)-galactose and galactosyl-β-(1→6)-galactosyl-β-(1→4)-glucose.

Volume and size effects of intermetallic compounds on the high-temperature oxidation behavior of Mo-Si-B alloys

Choi, Won June,Park, Chun Woong,Park, Jung Hyo,Kim, Young Do,Byun, Jong Min Elsevier 2019 INTERNATIONAL JOURNAL OF REFRACTORY METALS AND HAR Vol.81 No.-

<P><B>Abstract</B></P> <P>In this study, we investigated the high-temperature oxidation behavior of Mo-Si-B alloys with different volume fractions or sizes of intermetallic compound phases. Mo-Si-B alloys with uniformly dispersed intermetallic compound phases (Mo<SUB>5</SUB>SIB<SUB>2</SUB> and Mo<SUB>3</SUB>Si) in Mo solid solution matrix phase were fabricated using a novel powder metallurgical route, as introduced in our previous study. An isothermal oxidation test was conducted at 1300 °C for up to 10 h. The high-temperature oxidation resistance of Mo-Si-B alloys improved by increasing the volume fraction of intermetallic compound phases; this was a result of the increased amount of protective oxidized layers, which protect the Mo<SUB>ss</SUB> phase from oxidation by covering the surface. In addition, Mo-Si-B alloy with smaller intermetallic compound phases pulverized by high-energy ball milling had better high-temperature oxidation resistance compared to Mo-Si-B alloy with as-synthesized intermetallic compound phases.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The volume and size effects on intermetallic compound phases on high-temperature of Mo-Si-B alloys were investigated. </LI> <LI> Mo-Si-B alloys with different volume fractions or sizes of intermetallic compounds were fabricated by powder metallurgy. </LI> <LI> The oxidation resistance of Mo-Si-B alloys was improved with an increasing volume fraction of intermetallic compounds. </LI> <LI> The A3-P specimen had excellent oxidation property compared with the A3 specimen due to formation of oxide layer quickly. </LI> </UL> </P>

담관낭종에 관한 임상적 고찰

최용석,이진,이명석,전용철,김동준,전상현,주상언,계세협,장웅기,곽상택 대한소화기내시경학회 1995 Clinical Endoscopy Vol.15 No.2

We studied and analyzed 66 cases of choledochal cyst in a 9 year period from March, 1985 to December, l993 at Hangang, Kangnam and Chuncheon Sacred Heart Hospital. The results were as follows; 1) Age ranged from 1 year to 82 years and ll of 66 cases were below 10 years. The ratio of men to women was 1: 1.9. 2) The frequency of the triad of symptoms and signs were in order of abdominal pain 53 cases(80.3%), jaundice 12 cases(18.2%) and abdominal mass 9 cases(13.6%). The classical triad of pain, mass and jaundice was present in only 2 cases(3.0%). 3) Alkaline phosphatase was elevated in 42 cases(63.6%), hyperbilirubinemia in 29 cases(43.9%) and hyperamylasemia in 9 cases(13.6%). 4) Performed diagnostic procedures were ultrasonogram in 57 cases(86.4%), endo- scopic retrograde cholangiopancreatogram in 32 cases(48.5%), DISIDA scan in 18 cases(27.3%), computed tomogram in 14 cases(21.2%) and percutaneous transhepatic cholangiagram in 6 cases(9.1%). 5) Among 38 cases which ERCP or PTC were performed, according to the Todani's classification, Type I was seen in 28 cases(73.7%), Type IVA in 7 cases(18.4%), Type II in 2 cases(5.3%) and Type V in I case(2.6%). 6) The associated diseases were cholangitis in 15 cases(22.7%), choledocholithiasis in 12 cases(18.2%) and cholangiocarcinoma in 2 cases(3.0%). 7) Operative procedures were performed in 22 of 66 cases, excision of cyst with Roux-en-Y choledochojejunostomy in 17 cases, choledochocystojejunostomy in 2 cases and external drainage in 3 cases.

원발성 경화성 간세포암 1 예

최환주,심영웅,서대홍,김춘섭,송갑영,임홍섭,김충기,이겸철 대한내과학회 1997 대한내과학회지 Vol.53 No.2

Hepatoma is one of the most common malignant disease among cancers that occur in Korea. Recently, according ta developing imaging diagnostic technology and non surgical treatment the hepatoma is easily detected in early diagnosis and appropriate treatment. From this point of view, the histologic pattern of hepatoma is markedly important. This is the first reported case of sclerosing hepatocellular carcinoma, which is characterized by intense fibrosis, in which the tubular neoplastic structures are embedded. The incidence of sclerosing hepatocellular carcinoma is very rare. Therefore the rare histologic pattern of hepatoma might be introduced by many studies and reports. We recently experienced a case of sclerosing hepatocellular carcinoma.

Power Control of a Combined System with Fuel cell and Supercapacitor

Woong-Hyub Song,Jin-Young Kim,Haeyoung Park,Eui-Cheol Nho,In-Dong Kim,Heung-Geun Kim,Tae-Won Chun,Nam-Sup Choi 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

This paper deals with a combined system with fuel cell and supercapacitor to provide a power to grid or electrical load. The supercapacitor is used to compensate the slow response of the fuel cell at the instant of abrupt load change. The operation of the bidirectional DC/DC converter for a supercapacitor during charging and discharging is analyzed, and a power control method to maintain a DC link voltage constant is proposed. Simulation results for 3㎾ combined system show the usefulness of the proposed method.