http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
한강하구 염하수로 주변에서의 조석·조류 비대칭과 창·낙조 우세 분석
윤병일,우승범,Yoon, Byung-Il,Woo, Seung-Buhm 한국수자원학회 2012 한국수자원학회논문집 Vol.45 No.9
한강하구 염하수로 주변의 조석 조류 변형과 창 낙조 우세를 분석하기 위해서 4개 정점에서 동기간에 관측한 조류자료와 기 관측된 조석자료를 분석하였다. 조석 및 조류의 변형 정도는 $M_4/M_2$ 진폭비를 분석한 결과 상류로 갈수록 증가하며, 조석의 상대 위상차($2M_2-M_4$)를 계산하면 모든 정점의 값이 $180^{\circ}C$ 이하로 창조 우세를 보여준다. 그러나 조류자료의 통계분석 결과를 보면 조석 조화상수의 상대 위상차 결과와는 다르게 최강 평균 낙조가 창조에 비하여 강하게 나타나며, 정조시각을 이용하여 창조, 낙조 지속시간을 계산하면 낙조 지속시간이 길게 나타난다. 각 조류 관측정점의 주축 방향 유속성분의 상관도를 분석한 결과 인천항 이후 염하수로 북쪽입구까지는 상관도 값이 0.9 이상으로 높게 나타났다. 조류 분석결과에서 보여지는 낙조가 우세하고 낙조 지속시간이 긴 형태의 원인을 분석하기 위해서 조화분해 결과를 재구성하였다. 주 분조($M_2$)와 천해 분조($M_4$)를 결합하면 창조가 우세하고 낙조 지속시간이 긴 전형적인 창조우세 형태의 곡선이 나타난다. 그러나 이 곡선에 조류 성분의 산술 합으로 계산한 비 조류성분(잔차류)의 값을 더하면 낙조가 강해지고 낙조 지속시간이 긴 형태로 나타난다. 즉, 천해분조에 의해서 발생하는 상류방향의 흐름을 극복하는 담수와 하구 비선형 효과에 의해서 생성되는 장주기 조류성분과 같은 낙조방향의 평균적인 흐름이 존재하기 때문에 독특한 낙조심화 현상이 염하수로에서 나타난다. Han River estuary (HRE) is located at the middle of the western coast of Korea, and tidal currents were measured at 4 stations in this estuary during the winter season, and previously observed tide data was analyzed. The results of amplitude ratio of $M_4/M_2$ showed that increasing upward to estuary in the HRE. Tide harmonic constants of relative phase $2M_2-M_4$ represent flood dominance, with under 180 degree. But this method has a limit of analysis that typically based on the non-linear distortion of the tidal current in tidal lagoon system where freshwater discharge is assumed to be relatively small. The results of statistically tidal current data indicated that ebb current velocity would be great unlike tide data. Ebb and flood duration time is calculated by slack time of tidal current showed that ebb duration time is longer than flood. The results of correlation of analysis show high value (0.9) between tidal current stations from Incheon harbor to north entrance of Yeomha channel. We reconstructed to find the reasons for the features of ebb dominance the results of harmonic analysis. As major component ($M_2$) in combination with shallow water component ($M_4$), the tidal curve was presented flood dominance that has a flood current is stronger. However, these curve were changed to ebb dominance add up the non-harmonic components that had ebb direction flow by calculated tidally averaged current. The characteristic of enhancement on ebb is showed around the Yeomha channel in the HRE, because averaged flow which acts seaward such as long-term tidal current components due to non-linear effect and freshwater which overcome the flood current.
싸이클로헥센 증기 공정에 의한 산소량이 적은 실리콘카바이드 섬유의 개발
윤병일,최우철,김명주,김재성,김정일,강홍구,Yoon, Byungil,Choi, Woo Chul,Kim, Myeong Ju,Kim, Jae Sung,Kim, Jung il,Kang, Hong Gu 한국군사과학기술학회 2017 한국군사과학기술학회지 Vol.20 No.5
A chemical vapor curing method(CVC) was developed to cure polycarbosilane(PCS) fibers by using cyclohexene vapour as a non-oxygen active reactant, instead of air in oder to prepare the silicon carbide(SiC) fiber with low oxygen content. A cross-linked PCS fibers by cyclohexene vapor showed a completely different variation in IR spectra in comparison to the air-cured PCS fiber. CVC method resulted in less than 3 wt% in oxygen content. In this experiment conditions, The average tensile strength and modulus of SiC fiber obtained by CVC had 1995 MPa and 183 GPa respectively, which is higher than that of SiC fiber prepared by air-curing process.
말에서 급성장염과 관련된 페장에서의 Aspergillus감염증
윤병일,허권,김대용,박응복,하태영,서일복,Yoon, Byung-Il,Hur, Kwon,Kim, Dae-Yong,Bak, Ung-Bok,Ha, Tae-Young,Seo, Il-Bok 한국임상수의학회 1998 한국임상수의학회지 Vol.15 No.1
A 5 year-old male Throughbred horse housed in Korean Racing Association died after having enteritis and respiratory disorder for about 10 days. At necropsyi the left and right caudal lung lobes were reddenedi swolleni and contained numerous well-defined sublobular consolidated foci. The large intestine was diffusely reddened and covered with pseudomembranous exudates. Microscopicallyi multifocal areas of necrosis with mild to moderate infiltration of neutrophilsi macrophages and Iymphocytes as well as hemorrhage and edema were noted in the lung. The fungi having conidiophorei dome-shaped vesicles phialides and conidia which are characteristic of Apergillosis fumigatus was isolated from the lung. The colonic mucosa was transmurally necrotic and severe congestions edema and thrombi were observed in the submucosa. The embolic mycotic pneumonia present in this case Probably occured secondary to antibiotic therapy given for treatment of enteritis.
폴리카보실란 전구체로부터 고온 산화성분위기서 기계적물성이 우수한 파이롯-규모의 탄화규소섬유 제조공정 개발
윤병일 ( B. I. Yoon ),최우철 ( W. C. Choi ),김정일 ( J. I. Kim ),김재성 ( J. S. Kim ),강홍구 ( H. G. Kang ),김명주 ( M. J. Kim ) 한국복합재료학회 2017 Composites research Vol.30 No.2
본 연구의 목적은 고온 산화성 분위기하에서 기계적물성이 우수한 탄화규소섬유(SiC Fiber)를 파일롯-규모로의 생산 제조공정을 개발하는 것이다. 프리세라믹 전구체로서 폴리카보실란(PCS)을 사용하여 탄화규소섬유를 제조하였다. 연속성의 PCS 섬유는 300~350℃에서 PCS를 용융한 후에 용융방사로부터 얻었다. 열처리 전에 섬유의 불융화를 위하여 공기 분위기하에서 경화를 하였다. 경화 전, 후에 측정한 FT-IR 스펙트라 피크로부터 경화도를 계산하였다. 탄화규소섬유의 물성은 경화도에 따라 크게 영향을 받았다. 본 개발에서 열처리 중 섬유의 장력 조절로 우수한 물성을 갖는 탄화규소섬유를 얻었다. 탄화규소섬유의 화학조성과 기계적물성은 안정화섬유의 열처리시의 이송속도에 영향을 받았다. 탄화규소섬유를 공기분위기하 1000℃에서 1분부터 50시간까지 노출한 후에 인장시험을 수행하였다. 그 결과 인장강도는 약 60%까지 감소함을 보여주었다. 장시간 노출시험시 낮은 인장 강도값을 나타내는 섬유는 화학성분 분석시 섬유의 표면에 많은 탄소량을 함유하고 있었다. The purpose of this study is to develop silicon carbide fiber showing an excellent mechanical properties under highly oxidative conditions at high temperature. Polycarbosilane(PCS) as a preceramic precursor was used for making the SiC fiber. PCS fiber was taken by melt spinning method followed by melting the PCS at 300~350℃ in N2 gas. The Curing of PCS fiber was carried out in air oxygen chamber, prior to high temperature pyrolysis. Degree of cure was calculated by characteristic peak`s ratio of Si-H to Si-CH<sub>3</sub> in FT-IR spectra before and after curing of PCS fiber. The properties of SiC fiber was affected greatly by the degree of cure. The SiC fiber produced by controlling fiber tension during heat treatment showed good properties. The SiC fiber exposed to 1000℃ at air from 1 min. up to maximum 50 hrs showed around 60% reduction in tensile strength. We found that large amount of carbon content on the fiber surface after long-term exposure has resulted in lower tensile strength.
차세대 엔진용 세라믹복합재의 강화재로서 CVC공정에 의한 내산화성능이 우수한 고성능 탄화규소섬유 개발
윤병일(B.I, YOON),최우철(W.C, CHOI),김재성(J.S, KIM),김정일(J.I, KIM),강홍구(H.G, KANG),김명주(M.J, KIM) 한국추진공학회 2016 한국추진공학회 학술대회논문집 Vol.2016 No.12
The purpose of this study is to develop highly oxidative resistant silicon carbide fiber with less than 2 wt% of oxygen content for CMC composite applicable to various engines which can be used at above 1300℃ during long-term duration . In order to do that, we have developed CVC(chemical vapor curing) process to make the sic fiber with much lower oxygen content by using unsaturated hydrocarbon vapor than Si-O-C fiber cured by air oxidation atmosphere. The sic fiber cured by CVC process shows very low oxygen content similar to that of sic fiber obtained by electron beam curing. We found that the mechanism in curing process between air oxidation and CVC process were completely different. The mechanical property in the final sic fiber shows higher value in tensile strenth. As a results, this grade of sic fiber with low oxygen content will be available to apply as a fiber reinforcement of CMC for various gas turbine engines for aircraft, space and ultra high speed vehicles using ramjet or scramjet engine.