• Journal of Navigation and Port Research
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• v.30 no.5 s.111
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• pp.375-379
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• 2006

The keel attached on bottom of hull part prevents yacht from flowing sideway by sailing posture. The keel remove a heel moment and make the force of stability. The selection of suitable keel is important bemuse it has an influence on the safety. Also the appendage attached on bottom of keel part lower ballast weight center and have influence on hull stability. The optimum shape about the keel is very important. So this study has compared with characteristics of resistance depending on the shape of the lower part of fin keel in the same surface of water submersion, we have attached three different types of models of lower part of fin keels to the model ships using circulating water channel and analyzed resistance characteristics per shape to arrive at the optimum shape of reduction of resistance.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.1
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• pp.1-9
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• 2023

In order to improve the propeller cavitation performance composed of Cavitation Inception Speed (CIS), cavitation extent and pressure fluctuation, it needs to improve the wake distribution that flows into the propeller. The warship propeller cavitation is strongly influenced by the wake created at the V-strut of various appendages. The inflow characteristics of the V-strut were investigated using Computational Fluid Dynamics (CFD) and the twisted angles of the V-strut were aligned with upstream flow. The resistance and self-propulsion tests for the model ship with the existing and modified V-struts were conducted in Towing Tank (TT), and wake distribution, CIS, cavitation observation and pressure fluctuation tests were conducted in Large Cavitation Tunnel (LCT). The propeller behind the modified V-strut showed better cavitation characteristics than that behind the existing V-strut. Another model test was conducted to investigate rudder cavitation performance by the change of the V-strut. The rudder cavitation characteristics were not improved by the change of the operating conditions. On the basis of the present study, it is thought that the stern appendages for better propeller cavitation performance would be developed.

• Korean Circulation Journal
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• v.53 no.8
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• pp.566-577
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• 2023

Background and Objectives: The left atrial appendage (LAA) can contribute significantly to LA mechanical contraction. Nevertheless, the preventive effect of LAA occlusion during the maze procedure against cerebral infarction remains controversial. In this study, we compared the surgical, cardiac hemodynamic, and neurologic outcomes between LAA preservation and occlusion performed during the maze procedure. Methods: Between January 2015 and August 2021, 252 patients underwent the maze procedure using cryoablation at our medical center. After excluding patients according to our exclusion criteria (i.e., mechanical prosthesis implantation, preexisting LAA thrombus), LAA was preserved in 113 patients (non-occlusion group) and occluded in 75 patients (occlusion group). Outcomes were compared using propensity score matching (PSM). Results: PSM did not reveal significant intergroup differences in baseline characteristics between the non-occlusion (n=53) and occlusion (n=53) groups. During a median follow-up of 44 months, 2 patients in the non-occlusion group (3.8%) experienced ischemic strokes. There was no significant difference in the rate of freedom from stroke (p=0.19) and major adverse cardiac events (p=0.43) between the 2 groups. Through echocardiography at 1-year follow-up, a statistically significant difference in LA mechanical contraction was observed between the non-occlusion group and occlusion group (24 of 33 [72.7%] vs. 18 of 37 [48.6%], respectively; p=0.04). Conclusions: In this study, preservation of the LAA during the maze procedure resulted in better LA function than LAA occlusion, with similar rates of stroke.

• Journal of Chest Surgery
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• v.47 no.4
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• pp.394-397
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• 2014

Numerous technical modifications and various complications of the Senning procedure have been described in the literature. We describe the excellent clinical status and anatomic result of a 33-year-old patient who underwent a modified Senning operation using the left atrial appendage for reconstruction more than 30 years prior to presentation.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.177-181
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• 2003

Despite various forms have been developed and applied to ship hull forms, the superiority of hard chine type over other forms of fishing boat has been recognized so far. As one of the ways of forms for new concept fishing boat, this paper presents the result of a performance evaluation for newly developed forms of hull, appendage and deck house, which features that have esthetic forms.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.53-59
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• 2003

The Study of Hansun(Traditional Fishing Boat of Korea) is based on Fishing Bost Investigation Report which began in 1921. The Report was completed in 1927 with the conclusion of Southern sea Region and Western sea Region studies which included the investigation of the entire region. Based on this report, this paper surveys Hansun's characteristics style of boat and performance. The First couple of chapters are possibility of combining type of Hansun and modern Sailing Boat. As a result we find out that the hull form of Hansun is very similar with that of modern sailing boats and is a good candidate for the mother ship to develop the modern sailing boats for Korean sea.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.10a
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• pp.99-104
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• 2001

Thermally induced vibration response of solar array is investigated. The solar array model consists of composite thin walled beam and solar blanket, spreader bar. The composite thin walled beam incorporates a number of nonclassical effects of transverse shear, primary and secondary warping, rotary inertia and anisotropy of constituent materials. The solar blanket is a membrane subjected to uniform tension in the z direction. The spreader bar is a rigid member. A coupled thermal structure analysis that includes the effects of structural deformations on heating and temperature gradient is investigated. A stability criterion given in parameters for establishes the conditions for thermal flutter.

• Animal Systematics, Evolution and Diversity
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• v.5 no.2
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• pp.121-137
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• 1989

The larval stages of Scopimera longidactyla reared in the laboratory are described and illustrated in detail. The larval development consists of five zoeal and a megalopal stages. At 25$^{\circ}C$, the megalopa and the first crab instar were attained in 21 and 31 days after hatching, respectively. The larvae of Scopmera can be distinguished from those of other genera in the Scopimerinae and other sumbfamilies in the Ocypodidae by the relativelength of rostral carapace spines to carapace. The larvae of S. longidactyla are similar in morphology to those of S. globosa but distingished by the differences in larval , size, and appendage setation.

• Journal of Trauma and Injury
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• v.24 no.2
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• pp.168-170
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• 2011

Blunt cardiac rupture is uncommon and is associated with significant mortality. Patients with blunt cardiac rupture usually have combined injury and do not always show signs of cardiac tamponade, which delays the diagnosis of cardiac rupture and increases mortality. We report a case of cardiac rupture diagnosed and treated by using only thoracic exploration based on clinical impression, with radiologic studies, including even echocardiography, showing negative results.

• Journal of Chest Surgery
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• v.22 no.4
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• pp.667-671
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• 1989

Cor triatriatum is a rare congenital malformation of the heart in which a diaphragm stretches in a transverse plane through the left pulmonary venous chamber, thus creates two subchambers. The proximal chamber connects with the pulmonary veins, and the distal one has left auricle and the mitral valve. A 3 year old boy who had Cor triatriatum underwent surgical excision of the abnormal diaphragm in March, 1989 in Chungnam University Hospital. An obliquely oriented fibromuscular diaphragm divided the left atrium into a proximal chamber which was connected to the pulmonary veins and a distal chamber which had the atrial appendage and the mitral valve. The opening in the diaphragm was 5 mm in diameter. There were no associated abnormalities. The abnormal diaphragm was completely excised. The postoperative result was excellent.