• 동력기계공학회지
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• 제21권4호
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• pp.62-69
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• 2017

Because the moist foods like anchovy were appeared lower quality by hot air that occurred the lipid oxidation, the drying system by using the cold air has been used widely. This study has been carried out on the performance improvement according to arrangement angle of baffle and location of air duct in the cold air dryer. The main parameters in this study are the arrangement angles which are without, $0^{\circ}$, $10^{\circ}$, $20^{\circ}$, $30^{\circ}$ and $40^{\circ}$, and the locations of air duct are without, front, center and back. For this study we have conducted the numerical analysis method using fluent in order to obtain the optimal condition of the drying performance. As the arrangement angle of baffle is increased, the relative humidity is proportionally decreased, the value at $40^{\circ}$ is 42.2% that indicate the reduction of about 4% than without it. After the air duct was installed, the decreased relative humidity is showed within 1%, therefore, the effect of air duct for improving the dry capacity is more large than the arrangement angle of baffle. Finally, we have obtained the optimal conditions that the arrangement angle is $40^{\circ}$ with the air duct for a cold air dryer.

• Journal of Biosystems Engineering
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• 제16권2호
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• pp.133-141
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• 1991

This study was undertaken to investigate the structural and configurational characteristics of the tailings return-unit in the commercially available head-feed combines and to study the aero-dynamical behavior of the tailings in the units. The mathematical model of the motion of tailings in the thrower casing was developed and the simulated trajectories for different type of units was analyzed to compare with the measured ones. The air-stream velocity profile in various locations along the tailings returning duct was measured to find the effect of configurational characteristics and blade tip speed. The results of the study are summerized as follows. 1. The ejecting angle, which is the angle between the direction of the particle velocity ejecting from the blade and the horizontal axis, was found to be about $66^{\circ}$ in both the simulation and experiment. The angle was much greater than the setting angle of actual duct of the combines studied, which were $48{\sim}56^{\circ}$. By comparison of these results, it was suggested to change duct setting angle so as to reduce the frictional force, between the duct wall and tailings, by reducing the difference between the ejecting and setting angles. 2. The velocity of the air stream in the duct was in general higher in the upper bound of the duct compared to the lower and decreased as the stream went toward the end of duct. The comparison of the tailings units among the combines studied showed a superior performance with the tapered duct having small diameter in the outlet and with greater number of thrower blade.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.535-539
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• 2008

The machinery ventilation system in case of using the window nature ventilation is difficult due to strong outdoor wind pressure is common ventilation measure. increasing height and decreasing economical efficiency problem because of ventilation duct installation is rising and a measure is urgent. The purpose of this study is analysis required height according to each ventilation system and development of ventilation duct system to reducing height and model testing.

• Advances in pediatric surgery
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• 제15권1호
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• pp.11-17
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• 2009

Choledochal cyst is a congenital dilatation of the bile duct. Intrahepatic bile duct dilatation of type IVa by Todani's classification at the time of diagnosis resolved spontaneously after cyst excision and hepaticojejunostomy in many cases. It should be distinguished from the true cystic dilatation of the intrahepatic ducts, which tends to persist, albeit after some regression. We therefore studied postoperative intrahepatic duct dilatation changes in choledochal cyst. A total of seventy-six choledochal cysts were managed at the Division of Pediatric Surgery, Department of Surgery, Samsung Medical Center from May 1995 to December 2005. The ratio of males to females was 1:2.8. Preoperative radiologic diagnosis by Todani's classification was Type I (n=52, 68.4 %), II (n=1, 1.3 %), IVa (n=23, 30.3 %). Among fifty-five patients with intrahepatic bile duct dilatation we were able to follow up forty-eight by ultrasonography. Twenty-two patients were type IVa, and twenty-six patients were type I and showed intrahepatic duct dilatation. Mean follow-up duration was 35.3 months (9~105 months). Complete regression of dilated intrahepatic duct was observed in fifteen patients of type IVa and twenty-four patients of type I. Incomplete regression of dilated intrahepatic duct was observed in six patients in type IVa and two patients in type I. Only one patient in type IVa showed no change in ductal dilatation during a follow-up period of 15 months. We conclude that true type IVa is much less frequent than what was diagnosed preoperatively by imaging study. Therefore in type IVa patients who are diagnosed preoperatively the decision to perform liver resection should be carefully considered. Postoperative long term follow up of choledochal cyst with intrahepatic bile duct dilation is needed.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제4권1호
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• pp.108-112
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• 2001

Nonsyndromic intrahepatic bile duct paucity is known to be associated with several kinds of etiology such as infection, chromosomal anomaly, metabolic disease and idiopathic. We report a rare case of intrahepatic bile duct paucity with congenital bilateral vocal cord paralysis and 13q deletion.

• 대한수의학회지
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• 제37권2호
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• pp.253-262
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• 1997

To investigate morphological changes in the endocrine pancreas of chicken after pancreatic duct ligation, experimental animals were subdivided to control, 12 hours, 1 day, 2 days, 4 days, 7 days and 10 days groupes and all of three pancreatic ducts of chicken were ligated by surgical procedure and then the morphological changes were observed. In pancreatic islets, the vacuolation and invasion of connective tissue were occurred in all experimental groups and dissociation of pancreatic islets was detected in 4 days after pancreatic duct ligation and hold out to 10 days. The peak of the morphological changes in pancreatic islets was detected in 4 days after pancreatic duct ligation. In the results of immunohistochemical methods against glucagon, insulin, somatostatin and bovine pancreatic polypeptide(BPP), the number of immunoreactive pancreatic islets were decreased but the size increased with time, so the number of immunoreactive cells in each pancreatic islets were increased. Glucagon-immunoreactive cells were not changed but insulin-immunoreactive cells were decreased with time(p<0.05). BPP-immunoreactive cells were increased in 2 days after pancreatic duct ligation and then decreased with time(p<0.05). Somatostatin-immunoreactive cells were increased with time(p<0.05) in dark islets.

• Applied Microscopy
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• 제25권3호
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• pp.40-50
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• 1995

The results of observation on the salivary gland and salivary secretory duct of Korean slug, Incilaria fruhstorferi, in histochemical method are as follows. It is observed that there are six kinds of gland cells(Type-A, B, C, E and F) making up the salivary gland of Korean slug. Of those, type-A gland cell is observed as an acid mucous cell, and type-B, C, D, F gland cells as neutral mucous cells. But in type-E gland cell, while the membrane surrounding granules exhibit alcianophilia, granules show no reaction. The salivary secretory duct composing the salivary gland of Korean slug is composed of supporting epithelial cell and four kinds of gland cells(type-A, E, F and G), of which type-A, E, F gland cells compose both the acinus of salivary gland and endothelial tissue of salivary secretory duct, and are secreted into lumen through salivary secretory duct. But, type-G gland cell is observed only in the endothelium of salivary secretory duct and mucous granules are observed as neutral mucopolysaccharide.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제11권1호
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• pp.65-69
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• 2008

담도 폐쇄증은 수술적 치료가 필요하며 알라질 증후군은 대증적 치료가 가능하기 때문에 이를 감별하는 것이 중요하다. 저자들은 신생아기에 선천성 심장질환과 함께 담즙 정체 소견이 있는 환아에게서 원인 질환을 진단하는 과정에서 수술적 담관조영술 통해 제2형 담도 폐쇄증인 간관 폐쇄를 동반한 알라질 증후군 1예를 경험하였기에 보고하는 바이다.

• International Journal of Fluid Machinery and Systems
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• 제10권1호
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• pp.19-29
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• 2017

An objective of this study is to demonstrate the validity of using a small wind turbine to recover the fluid energy flowing out of an exhaust duct for the generation of power. In these experiments, a butterfly wind turbine of a vertical axis type (D = 0.4 m) is used. The output performance is measured at various locations relative to the exit of a small wind tunnel (W = 0.65 m), representing the performance expected in an exhaust duct flow. Two-dimensional numerical analysis qualitatively agrees with the experimental results for the wind turbine power coefficient and rate of energy recovery. When the turbine is far from the duct exit (more than 2.5 D), an energy recovery rate of approximately 1.3% is obtained.

• 한국해양공학회지
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• 제31권3호
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• pp.183-188
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• 2017

This paper provides numerical results for the estimation of the efficiency of KRISO energy saving devices in the design stage. A finite volume method is used to solve Reynolds averaged Navier-Stokes (RANS) equations, where the SST k-$\omega$ model is selected for turbulence closure. The propeller rotating motion is determined using a rigid body motion (RBM) scheme, which is called a sliding mesh technique. The numerical analysis focuses on predicting the power reduction by the designed KRISO devices (K-DUCT) under a self-propulsion condition. The present numerical results show good agreement with the available experimental data. Finally, it is concluded that CFD can be a useful method, along with model tests, for assessing the performance of energy saving devices for propulsion efficiency improvement.