• 대한환경공학회지
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• 제29권1호
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• pp.47-53
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• 2007

본 연구의 목적은 대형 석탄 화력 발전소에 DSI(Dry Sorbent Injection)공법 적용 가능성에 대한 연구로서 전산유체역학(CFD; Computational Fluid Dynamics) 기법을 이용하여 N화력 S화력발전 본부에서 운용중인 500MW급 유연탄 발전시설의 보일러 후단에서 전기 집진기 전단까지 덕트 내의 배기가스에 대한 삼차원 유동장에 대한 전산 해석을 수행하였다. CFD상용코드를 이용하여 DSI공법적용 전 기술적 방향을 제시하였는데 덕트의 형상, 탈황제 분사 위치, 분사 속도에 따른 탈황제의 관내 분산 특성에 대한 연구를 중점으로 하였다. 그 결과 DSI공법 적용에 관한 최적의 조건을 확립하였고 그 중 탈황제의 분산에 가장 큰 영향을 미치는 인자는 덕트형상임을 확인하였으며 이에 Lobed-plate라는 탈황제 분산판을 적용한 결과 덕트 내 탈황제의 고른 분산을 유도할 수 있었다.

• 한국대기환경학회지
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• 제27권5호
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• pp.614-622
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• 2011

In this study, a new tunnel ventilation method with a high velocity air curtain flow has been investigated for improving the ventilation exhaust efficiency and removing air pollutants in subway tunnels. At upper or lower position right downstream of a main duct connected with a ventilation opening, air curtain flows were suppled into the main duct where the air flow velocity was in the range of 2~6 m/s. Exhaust efficiency was monitored for both cases with and without air curtain flow for different air velocities, locations and injection angles of the air curtain. Particulate matter concentrations (PM10, PM2.5 and PM1.0) were also checked at both the main duct and ventilation opening before and after supplying air curtain flows. Lower air velocity of the main duct flow, higher air velocity of the air curtain led to higher exhaust efficiency and the air curtain condition of 30..inclined injection toward the main flow showed the maximum exhaust efficiency. The exhaust efficiency of about 24% without the air curtain could be improved to about 34% after using the air curtain flow. PM concentration decreased at the main duct and increased at the ventilation opening after using the air curtain flow. Therefore, the suggested method to use air curtain flows in tunnels will be probably one of the promising tools to reduce air pollutants in subway tunnels.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제17권3호
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• pp.170-177
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• 2014

Purpose: Choledochal cyst is a cystic dilatation of common bile duct. Although the etiology is presently uncertain, anomalous pancreaticobiliary ductal union (APBDU) is thought to be a major etiology of choledochal cyst. In this study, we analyzed the clinical and anatomical characteristics and pathologies of patients diagnosed with choledochal cyst in a single institute for 25 years. Methods: A total of 113 patients, diagnosed with choledochal cyst and who received an operation in Severance Children's Hospital from January 1988 to May 2013, were included. Medical records were reviewed, including clinical and demographic data, surgical procedures. Abdominal ultrasonography, magnetic resonance cholangiopancreatography, and intraoperative cholangiography were used as diagnostic tools for evaluation and classification of choledochal cyst and the presence of anomalous pancreaticobiliary ductal union. Todani's classification, and relationship between APBDU and surgical pathology. Results: Among 113 patients, 77 patients (68.1%) presented symptoms such as hepatitis, pancreatitis and/or cholecystitis. Eighty three patients (73.5%) had APBDU, and 94 patients (83.2%) showed inflammatory pathologic changes. APBDU, pathologic inflammation, and serological abnormalities such as hepatitis or pancreatitis showed a statistically significant correlation to one another. Conclusion: APBDU is thought to be one of the etiologic factors of choledochal cyst. It is related to the inflammatory changes in bile duct that can lead to the cystic dilatation.

• Archives of Pharmacal Research
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• 제24권4호
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• pp.327-332
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• 2001

The antifibrotic effects of hot water extract (WEC), intracellular biopolymer (IPC) and extracellular biopolymers (EPC) from mycelial liquid culture of Cordyceps militaris on liver fibrosis were studied. Liver fibrosis was induced by a bile duct ligation and scission (BDL/S) operation, duration of 4 weeks in rats. In BDL/S rats, the levels of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), total bilirubin in serum and hydroxyproline content in liver were dramatically increased. The WEC or IPC treatment (30mg/kg/day for 4 weeks, p.o.) in BDL/S rats reduced the serum AST, ALT and ALP levels significantly (p<0.01). The EPC treatment (30 mg/kg /day for 4 weeks, p.o.) reduced the serum ALT, AST and ALP levels significantly (p<0.01). Malondialdehyde contents in liver treated with WEC, IPC or EPC were significantly reduced (p <0.05). But Liver hydroxyproline content was decreased only in EPC treated BDL/S rats to 55% that of BDL/S control rats (p < 0.01). The morphological characteristics and expression of alpha smooth muscle like actin in fibrotic liver, which appeared in BDL/S control group were improved in EPC treated fibrotic liver. These results indicate that IPC (30 mg/kg /day for 4 weeks, p.o.) has an antifibrotic effect on fibrotic rats induced by BDL/S.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.803-808
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• 2006

This paper was a study about noise reduction through flow stabilization in duel using experimental method and numerical analysis at the same time. To determine the fan's type three kinds of fans(axial fan, centrifugal fan, and axial fan with centrifugal type) was examined to investigate the suitability for duct. As a result, under the equal number of rotation 2000 RPM, performance of an axial fan with centrifugal type was the most superior by 55dBA at 4.3CMM among other fans. After this, analyzed the results of the numerical analysis to find out the optimum design of pitch angle such as $0^{\circ},\;10^{\circ},\;15^{\circ}\;and\;20^{\circ}$. The intensity of turbulence was low when pitch angle was $15^{\circ}$ and air volume became peak by 5.08 CMM. It was observed that axis component of velocity increased gradually when pitch angle increased from $0^{\circ}\;to\;20^{\circ}$. Finally, designed the shapes of D/S(Down Stream) in duct that agreed inlet angle($\delta$) of stationary blades with pitch angle($\beta$) of axial fan with centrifugal type and derived flow to duct medial, and changed the shape of motor-mount to reduce occurance of unstable vortex in tip of impeller, and embodied noise reduction and improvement of air flow rate through flow stabilization.

• Korean Journal of Radiology
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• 제22권1호
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• pp.41-62
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• 2021

Radiologic imaging is important for evaluating extrahepatic bile duct (EHD) cancers; it is used for staging tumors and evaluating the suitability of surgical resection, as surgery may be contraindicated in some cases regardless of tumor stage. However, the published general recommendations for EHD cancer and recommendations guided by the perspectives of radiologists are limited. The Korean Society of Abdominal Radiology (KSAR) study group for EHD cancer developed key questions and corresponding recommendations for the radiologic evaluation of EHD cancer and organized them into 4 sections: nomenclature and definition, imaging technique, cancer evaluation, and tumor response. A structured reporting form was also developed to allow the progressive accumulation of standardized data, which will facilitate multicenter studies and contribute more evidence for the development of recommendations.

• The Korean Journal of Pain
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• 제31권3호
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• pp.221-222
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• 2018

• 한국패류학회:학술대회논문집
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• 한국패류학회 2002년도 추계학술발표회
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• pp.8-9
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• 2002

• 대한설비공학회지:설비저널
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• 제28권2호
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• pp.94-107
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• 1999

• 시멘트 심포지엄
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• 27호
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• pp.81-84
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• 2000