• Journal of Chest Surgery
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• v.12 no.3
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• pp.197-206
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• 1979

The most common abnormal relationship between the great arteries and ventricle is transposition of great arteries, among which complete D-transposition is a common and lethal malformation. Without appropriate treatment, the infant born with transposition of the great arteries rarely survives the first year of life. In contrast to the grim hopelessness of only a few years ago, modern aggressive palliative and corrective surgical interventions can provide such infants with considerable hope for adolescent and adult life. Up until this time, intraatrial baffle technique for re-direction of venous return, which was proposed by Mustard originally, has been successfully applied to infants and children in many foreign clinics with decreasing trend of the operative risk. In this report, we present one case of a 4 year-old girl having complete D-transposition of the great arteries with atrial septal defect, and reviewed the relevant literatures.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.912-918
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• 2009

In this paper, we carried out a comparative analysis of partial discharge(PD) patterns caused by deterioration of cast-resin and oil insulation systems. Various electrode systems were fabricated such as needle-needle, needle-plane and plane-plane to simulate defects that may exist in the insulation system of transformers. A low-noise amplifier which has a gain of 40 dB and a frequency bandwidth of 500 kHz $\sim$ 30 MHz (-3 dB) was designed to detect small PD signals. From the analysis of acquired PD signals, we could find that a unique PD pattern is formed according to types of defect. These data will be applied usefully to diagnose insulation condition of transformers.

• Korean Journal of Materials Research
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• v.14 no.6
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• pp.379-388
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• 2004

To investigate the effect of D-ferrite on the hot workability and surface defect of STS 304 billets containing 3 wt. % Cu, microstructure observations and high temperature mechanical properties test were carried out for the specimens extracted mainly from raw or oxidized billets. It was found that the total $\delta$-ferrite content has little influence on the hot workability, even though the fracture cracks due to high temperature tension or compression test were initiated and propagated mostly along $\delta$/${\gamma}$ boundary in the specimens. On the other hand, it was supposed that the direct causes of surface defects in the wire rolled from the as-continuously cast billet were the grain boundary embrittlement arose from the deep diffusion of oxygen into the grain boundary, and the oxidation of $\delta$-ferrite connected by a grain boundary to the surface during the billet reheating process as well.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.123-126
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• 2004

We have demonstrated the fabrication of patterned 3D photonic crystals by holographic lithography in conjunction with soft lithography. Holographic lithography created 3D ordered macroporous structures and soft lithography made tailored defects. Because the hard baked photoresist pattern possessed high resistance against the uncured photoresist solution and the refractive index did not change appreciably by hard baking, a crosslinked photoresist was used as a relief pattern for the holographic fabrication of patterned 3D photonic crystals. More complicated defect geometries might be easily obtained with more complicated patterns on PDMS stamps. Moreover, the present results might be used as templates for 3D PCs of highindex defects that can be exploited as optical waveguides and optical circuits.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.277-278
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• 1998

CT/MRI images were frequently taken to evaluate the anatomic structure and disease status, and to plan the treatment modality for oral and maxillofacial surgery. However, surgeons have many difficulties in reading and understanding 2D images without long time experiences. This study presents the method of 3D reconstruction with fine CT slices and its clinical application. We applied this method a clinical patient with oral and maxillofacial trauma and produced 3D reconstructed model which shows the fracture line in panfacial area and bone defect.

• Journal of the Korea Safety Management & Science
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• v.25 no.2
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• pp.153-158
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• 2023

This research was conducted to reduce the defect rate caused by nozzle clogging of printing heads used in binder jet 3D printers. The binder jet 3D printing technology may adhere to the printing head nozzle by dispersing powder due to mechanical operation such as transferring the printing head and supplying powder, and may cause nozzle clogging by natural curing at the nozzle end depending on the type of binder used. To solve this problem, this study created a cleaning module exclusively for printing heads to check whether the durability of printing heads is improved through analysis of printing results before and after using the cleaning module. To this end, this research used a thermal bubble jet printing head, and the used powder was studied using gypsum powder.

• Journal of Practical Engineering Education
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• v.15 no.2
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• pp.419-427
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• 2023

In this study, optimal adhesion conditions to alleviate defects caused by heat shrinkage with FDM type 3D printers with machine learning are researched. Machine learning is one of the "statistical methods of extracting the law from data" and can be classified as supervised learning, unsupervised learning and reinforcement learning. Among them, a function model for adhesion between the bed and the output is presented using supervised learning specialized for optimization, which can be expected to reduce output defects with FDM type 3D printers by deriving conditions for optimum adhesion between the bed and the output. Machine learning codes prepared using Python generate a function model that predicts the effect of operating variables on adhesion using data obtained through adhesion testing. The adhesion prediction data and verification data have been shown to be very consistent, and the potential of this method is explained by conclusions.

• Journal of Chest Surgery
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• v.29 no.1
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• pp.32-37
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• 1996

Between May 1991 and September 1995, 7 patients underwent surgical repair of ventricular septal defect (VSD) complicated with myocardial infarction in Asan Medical Center. The patients included two male and five female. The ages of patients were ranged from 54 years to 76 years with a mean of 65 years. The sites of postinfarction ventricular septal defect were consist of anterior septal defect in 6 patients and anteroposterior septal defect in 1 patient. Preoperative 2D-echocardiography & angiography were performed in all patients in order to measure ventricular function and evaluate the extent of coronary artery disease. The operations were delayed till mean 24 $\pm$ 12days after myocardial infarction. All patients underwent infarctectomy and Teflon patch closures through the area of the left ventricle infarction or aneurysm in the anterior or apical aspect of postinfarction ventricular septal defect. The ventricular septal defect repaired simultaneously with coronary artery b pass graft in 3 patients, with ventricular aneurysmectomy in 5 patients, and with left ventricular thrombectomy in 1 patient. Patch fixation in the left side of interventricular septum by tracts-septal interrupted pledget suture reduced the recurrence rate of VSD. There were 2 postoperative complications : One with pneumonia, 1 patient with the skin necrosis of left thigh. There was ilo early death. The 6 patients except for one emigrant were followed up postoperatively between 3 and 63 months(mean .28 months), without any sequelae and late death. They are in New York Heart Association functional class I-II.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.169-170
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• 2013

• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.1023-1033
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• 2014

In this paper, performance improved hole-filling algorithm which includes the boundary noise removing pre-process that can be used for an arbitrary virtual view synthesis has been proposed. Boundary noise occurs due to the boundary mismatch between depth and texture images during the 3D warping process and it usually causes unusual defects in a generated virtual view. Common-hole is impossible to recover by using only a given original view as a reference and most of the conventional algorithms generate unnatural views that include constrained parts of the texture. To remove the boundary noise, we first find occlusion regions and expand these regions to the common-hole region in the synthesized view. Then, we fill the common-hole using the spiral weighted average algorithm and the gradient searching algorithm. The spiral weighted average algorithm keeps the boundary of each object well by using depth information and the gradient searching algorithm preserves the details. We tried to combine strong points of both the spiral weighted average algorithm and the gradient searching algorithm. We also tried to reduce the flickering defect that exists around the filled common-hole region by using a probability mask. The experimental results show that the proposed algorithm performs much better than the conventional algorithms.