• Journal of the Korean Society of Visualization
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• v.14 no.2
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• pp.12-17
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• 2016

In this work, we investigate the flow velocity controllability of a diffuser-type multiple hydrofoil duct by experimental and numerical flow visualization approaches. The flow velocity controllability is analyzed by changing the angle of the hydrofoil near the outlet, which is the diffuser, while the incoming flow velocity is 0.6 m/s in the experiment. When the diffuser angle is changed from 0 to 7.5 degree, the maximum velocity inside the duct is varied from 1.35 m/s to 1.52 m/s. Also, it is shown from the numerical analysis that the maximum velocity is varied from 1.09 m/s to 1.17 m/s in the same condition. Thus, the aspect of the acceleration in the duct due to the increase of the diffuser angle is similar between the both approaches. Therefore, the multiple hydrofoil duct can be used to control the flow speed inside the duct for continuously extracting power close to a rated capacity.

• 한국전산유체공학회:학술대회논문집
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• 2002.10a
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• pp.121-126
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• 2002

Aircraft propulsion systems often use diffusing S-duct to convey air flow from the wing or fuselage intake to the engine compressor, Well designed S-duct should incur minimal total pressure losses and deliver nearly uniform flow with small transverse velocity components at the engine compressor entrance. Reduced total pressure recovery lowers propulsion efficiency and nonuniform flow conditions at the engine face lower engine stall limits. In this study, S-duct which has maximum total pressure recovery and nearly uniform flow profiles at the compressure intake should be found using design optimization methods with 3-dimensional Wavier-Stokes analyses.

• Journal of the Korean Society of Safety
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• v.17 no.4
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• pp.61-65
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• 2002

Nonpremixed counterflow flames at low strain rates, $ag=12s^{-1}$ and $12s^{-1}$, were numerically simulated to investigate the effects of the duct thickness on the flame structure in normal gravity. For small values of the duct thickness, the positions of the flame and stagnation point were highly sensitive to the duct thickness. When the duct thickness was greater than 6mm, however, the effects of the duct thickness on the flame structure were negligible. The computed temperature along the duct centerline agreed well with measurements.

• Journal of Animal Environmental Science
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• v.8 no.2
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• pp.73-78
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• 2002

The experiment was carried out to investigate the optimal air velocity for improving the ventilation efficiency of duct ventilation system used in Korean swine building. The results are followed ; In 2.2 m height of duct, the air velocity of hole was 5.0 m/s as the over level of recommendation. In different hole interval, the air velocity was various of 4.6${\sim}$11.6 m/s in narrow hole interval, 5.4${\sim}$10.9 m/s in broad hole interval. But the air velocity was 6.6${\sim}$7.7 m/s in duct system pierced hole with equal interval, and it was equal velocity in different parts of duct in this hole interval.

• 대한상한금궤의학회지
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• v.4 no.1
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• pp.49-55
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• 2012

Objectives : This research is to prove the effectiveness of DahuangMudan-Tang(大黃牡丹湯) in curing the Bartholin's duct abscess Methods : to achieve the goal of this research, the patient was diagnosed as 'abscess(腫膿)' treatabling by Dahuang(大黃) in GoBeob-medicine(古法醫學). I gave Dahuang Mudan-Tang(大黃牡丹湯) to the selected patient and observed the progress Results : the results indicate the followings 1. After the treatment with DahuangMudan-Tang(大黃牡丹湯), the symptoms of the Bartholin's duct abscess was significantly improved. 2. The external medicine with DahuangMudan-Tang(大黃牡丹湯) was more effective to cure the Bartholin's duct abscess.

• Journal of Veterinary Clinics
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• v.18 no.2
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• pp.182-184
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• 2001

2001년 4월 19일에 11살 된 말티즈 암캐의 비정상적 자궁에 대한 검사의뢰가 들어왔다. 육안적 검사에서 얇은 막으로 된 다양한 자궁 낭종이 관찰되었다. 그 수는 5개이며 그중 2개는 자궁체의 장막면에 위치하고 있었으며 7∼8 mm 정도의 직경을 가지고 있었다. 나머지 3개는 직경 1∼2 mm 정도의 크기이며 자궁각의 장막면에 위치하고 있었고, 절개시 모든 낭종들은 장액성 액체들로 가득 차 있었다. 병리조직학적 검사에서는 모든 낭종들이 자궁의 장막하에 존재하고 있었다. 낭종의 상피세포들과 이들의 위치는 모두 Gartner's duct와 동일한 것들이었고, 따라서 Gartner's duct cyst로 진단하게 되었다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.18 no.3
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• pp.180-186
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• 2015

Purpose: Bile duct dilatation is a relatively common sonographic finding; nevertheless, its clinical significance in children is controversial because little research has been done in the area. Therefore, we investigated the natural course and clinical significance of biliary duct dilatation in children. Methods: We performed a retrospective study of 181 children (range, 1-day-old to 17-year-old) in whom dilatation of the intrahepatic duct and/or common hepatic duct and/or common bile duct was detected by abdominal ultrasonography at the Severance Children's Hospital between November 2005 and March 2014. We reviewed and analyzed laboratory test results, clinical manifestations, and clinical course in these patients. Results: Pediatric patients (n=181) were enrolled in the study and divided into two groups. The first group included 59 subjects, without definitive cause of bile duct dilatation, who did not require treatment; the second group included 122 subjects, with definitive cause of bile duct dilatation or underlying biliary disease, who did require treatment. In the first group, 24 patients (40.7%) showed spontaneous resolution of bile duct dilatation, 20 patients (33.9%) showed no change, and 15 patients (25.4%) were lost to follow-up. In the second group, 31 patients were diagnosed with choledochal cysts, and 91 patients presented with biliary tract dilatations due to secondary causes, such as gallbladder or liver disease, post-operative complications, or malignancy. Conclusion: Biliary dilatation in pediatric patients without symptoms, and without laboratory and other sonographic abnormalities, showed a benign clinical course. No pathologic conditions were noted on follow-up ultrasonography.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.2
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• pp.211-217
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• 2006

This study is focused on the analysis of the characteristics of marine HVAC duct. These results will be applied to develope a robot which is for maintaining a cabin comfort, convenience and healthy through HVAC duct. The followings are the results of this study. (1) The evaluated items which proposed by at the view point of robot's function can be adapted to other vessels for the same purpose, (2) For the case of round type duct. the maximized conditions which robot has to have are straight length of 40.152mm, inclination of $45^{\circ}$. horizontal bending of $90^{\circ}$. increasing diameter of 1.28 times, and 0.625 times decreasing diameter in branch. (3) For the case of rectangular type duct. the maximized conditions are straight length of 15.987mm. aspect ratio of 4.17:1, inclination of $18.92^{\circ}$. horizontal bending of $90^{\circ}$, and 0.65 times decreasing diameter in branch.

• Korean Journal of Head & Neck Oncology
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• v.22 no.2
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• pp.171-174
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• 2006

Tumors rarely arise in the sublingual salivary glands. They should be considered malignant until proved otherwise. Adenoid cystic carcinoma is most commonly encountered malignant tumor of the sublingual gland. We report a case of adenoid cystic carcinoma arising from the sublingual gland. Moreover, the sublingual gland had anatomic variation of main duct(Bartholin's duct) which is connected to Wharton's duct.

• Korean Journal of Head & Neck Oncology
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• v.27 no.2
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• pp.215-217
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• 2011

Salivary gland calculi account for the most common disease of the salivary glands. We experienced a rare case of submandibular duct(Wharton's duct) calculi of unusual size and shape in a 40 year-old male patient, who presented with pain and swelling in the region of submandibular gland. The author describes the management of this patient and reviews the literature.