• Journal of the Optical Society of Korea
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• v.19 no.6
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• pp.619-628
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• 2015

In this paper, we consider a method for estimating a stripe-type defect and the reconstruction of a defect-free L/S type mask used in lithography. Comparing diffraction patterns of defected and defect-free masks, we derive equations for the estimation of the location and size of the defect. We construct an analytical model for this problem and derive closed form equations to determine the location and size using phase retrieval problem solving techniques. Consequently, we develop an algorithm that determines a defect-free mask pattern. An example shows the validity of the equations.

• Journal of Korea Foundry Society
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• v.22 no.6
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• pp.309-314
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• 2002

The effect of mold density and evacuation on surface defect of high chromium cast iron upon EPC process was investigated. Under evacuation of $0.1{\sim}0.3$ atm, surface defects were carbon defect, burn on and misrun. Carbon defect was augmented by increasing mold density from 0.011 g/$cm^3$ to 0.03 g/$cm^3$ under evacuation of $0.1{\sim}0.3$ atm, but carbon defect was decreased by increasing evacuation from 0.1 to 0.3 atm. Burn-on wasn't found under evacuation of 0.1 atm regardless of mold density, but burn-on was augmented by increasing evacuation from 0.2 to 0.3 atm and decreased by reducing mold density. Misrun was only found under 0.1 atm evacuation and 0.011 g/$cm^3$ mold density.

• Journal of Periodontal and Implant Science
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• v.36 no.2
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• pp.427-434
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• 2006

The form of furcation influence both the pathogenesis of periodontal destruction and therapeutic results. The present study was performed to evaluate the effect of root trunk length on clinical outcomes of guided tissue regeneration. Total 30 mandibular first molars were evaluated in this study. Probing pocket depth, clinical attachment level, vertical defect depth and horizontal defect depth were measured at baseline and 6 month after GTR. Correlation coefficients between root trunk length and other clinical measurement were analyzed. The results of this study were as follows 1. The mean root trunk length in lower 1st molar was 2.15 mm. 2. Probing pocket depth, clinical attachment level, vertical defect depth and horizontal defect depth were significantly reduced at 6 month postoperatively compared to values of baseline 3. Correlation coefficient between root trunk length and vertical defect depth at baseline was 0.406 showing the positive correlation 4. Correlation coefficient between root trunk length and horizontal defect depth at baseline was -0.463 showing the negative correlation. 5. Correlation coefficient between root trunk length and decrease of horizontal defect depth after GTR was 0.654 showing the positive correlation. In conclusion, the root trunk length maybe effector for clinical outcome after guided tissue regeneration.

• Structural Engineering and Mechanics
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• v.84 no.6
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• pp.799-811
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• 2022

Adhesive bonding has seen rapid development in recent years, with emphasis to composite patch repairing processes of geometric defects in aeronautical structures. However, its use is still limited given its low resistance to climatic conditions and requirement of specialized labor to avoid fabrication induced defects, such as air bubbles, cracks, and cavities. This work aims to numerically analyze, by the finite element method, the failure behavior of a damaged plate, in the form of a bonding defect, and repaired by an adhesively bonded composite patch. The position and size of the defect were studied. The results of the numerical analysis clearly showed that the position of the defect in the adhesive layer has a large effect on the value of J-Integral. The reduction in the value of J-Integral is also related to the composite stacking sequence which, according to the mechanical properties of the ply, provides better load transfer from the plate to the repair piece through the adhesive. In addition, the increase in the applied load significantly affects the value of the J-Integral at the crack tip in the presence of a bonding defect, even for small dimensions, by reducing the load transfer.

• Journal of Chest Surgery
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• v.11 no.2
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• pp.175-180
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• 1978

A rare form of tetralogy of Fallot, in which large ventricular septal defect was located at subpulmonary position rather than beneath a well developed crista supraventricularis was operated in this Department. This case satisfied the criteria for the diagnosis of tetralogy of Fallot, having large ventricular septal defect beneath the aortic valve with overriding of aorta, pulmonary stenosis and right ventricular hypeFtrophy. The operation was done through a median sternotomy using cardiopulmonary bypass. A vertical right ventriculotomy was extended to the pulmonary valve ring. Pulmonary and aortic valve were adjacent to each other, in contrast to the situation of classic tetralogy of Fallot. Pulmonary valvulotomy was done and ventricular septal defect was closed. with Teflon, and right ventricular outflow tract was reconstructed with woven Dacron covered by pericardial patch after minimal resection of septal band. The post-operatiove courses was uneventful except wound infection. The patient was discharged 15 days after open heart surgery.

• Transactions of Materials Processing
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• v.8 no.6
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• pp.612-619
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• 1999

Internal and external defects of an inner pulley for automobile air conditioner are investigated in this study. Inner pulley is a part of compressor clutch assembly of automobile air conditioner. In cold forging of inner pulley, the design requirement are to keep the same height of the inner rib and outer one and to make uniform distribution of hardness in the forged product. At the end of the forging of inner pulley, the piping defect as an external defect begins to form at the back center of the billet. The internal crack as an internal defect also occur at the adiabatic shear band which usually has maximum ductile fracture value. It is important to predict when the internal and external defects occur during the deformation process, in order to minimize the amount of discard that is generated. The finite element simulations are applied to analyze the defects. The validity of the computational results are examined by experiments. These computational results are in good agreement with the experimental ones.

• Journal of Welding and Joining
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• v.7 no.3
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• pp.36-43
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• 1989

The furnace brazing in a Ar of copper to martensitic stainless steel(13.5Cr) using Cu-(5~8%)P-(0~8%)Sn powders was investigated. Shear strength, wettability, reacted layer, defect ratio at the stainless steel interface was evaluated. As Sn was added to the Cu-P powders, defect ratio and P content at the stainless steel interface decreased. And also as Sn was added, defect form at the stainless steel interface changed from the continuous layer to the discrete type, and shear strength of the brazed joint increased.

• Archives of Craniofacial Surgery
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• v.9 no.2
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• pp.81-84
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• 2008

Purpose: The goals of cranioplasty are to protect the brain from trauma and restore normal cranial contour with as few complication as possible. In patient who suffered from cranial defect, the most satisfactory form of cranioplasty may be archived with autogenous bone grafts. We report on the treatment of large frontal bone defect using pericranial flap and split-rib graft. Methods: A 29-year-old male was referred to our department. He was involved in an automobile accident resulting in large frontal bone and sinus defect and skull basal defect. The reconstruction was undertaken using galeal frontalis myofascial flap and split-rib cranioplasty using bicoronal incision. Results: The postoperative course was successful. For 9 months follow up period, there was no complication about hematoma, infection, CSF leakage and washboard deformity. He was pleased with the results even when absolute symmetry was not achieved. Conclusion: We experienced large frontal bone and sinus defect and skull basal defect patient and successfully treated with split-rib graft and galeal frontalis myofascial flap.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.12
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• pp.6043-6062
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• 2019

Low-rank matrix decomposition has shown its capability in many applications such as image in-painting, de-noising, background reconstruction and defect detection etc. In this paper, we consider the texture background of rail track images and the sparse foreground of the defects to construct a low-rank matrix decomposition model with block sparsity for defect inspection of rail tracks, which jointly minimizes the nuclear norm and the 2-1 norm. Similar to ADM, an alternative method is proposed in this study to solve the optimization problem. After image decomposition, the defect areas in the resulting low-rank image will form dark stripes that horizontally cross the entire image, indicating the preciselocations of the defects. Finally, a two-stage defect extraction method is proposed to locate the defect areas. The experimental results of the two datasets show that our algorithm achieved better performance compared with other methods.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.2
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• pp.1-12
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• 2023

To make semiconductor chips, a number of complex semiconductor manufacturing processes are required. Semiconductor chips that have undergone complex processes are subjected to EDS(Electrical Die Sorting) tests to check product quality, and a wafer bin map reflecting the information about the normal and defective chips is created. Defective chips found in the wafer bin map form various patterns, which are called defective patterns, and the defective patterns are a very important clue in determining the cause of defects in the process and design of semiconductors. Therefore, it is desired to automatically and quickly detect defective patterns in the field, and various methods have been proposed to detect defective patterns. Existing methods have considered simple, complex, and new defect patterns, but they had the disadvantage of being unable to provide field engineers the evidence of classification results through deep learning. It is necessary to supplement this and provide detailed information on the size, location, and patterns of the defects. In this paper, we propose an anomaly detection framework that can be explained through FCDD(Fully Convolutional Data Description) trained only with normal data to provide field engineers with details such as detection results of abnormal defect patterns, defect size, and location of defect patterns on wafer bin map. The results are analyzed using open dataset, providing prominent results of the proposed anomaly detection framework.