• 한국시뮬레이션학회논문지
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• 제11권3호
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• pp.49-58
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• 2002

It takes 2 or 3 months to manufacture memory device. Defect has to exist owing to hundreds of processes. If there are too many defects, the memory has to be rejected. But if there are a few defects, it will be more efficient and cost reducing for the company to use it by repairing. Therefore, laser-repair process is needed for such a reason and redundancy analysis is needed to establish correct target of laser-repair process. The equipment development company had provided the redundancy analysis and each development company had developed and provided separately. So, to analyze the similar type of defects, redundancy analysis time can be very different by the manufacture. The purpose of this research is to strengthen the competitive price and to apply correlation concept in business for reducing the redundancy analysis time to repair the defects

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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• pp.87-95
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• 1998

This study proposes the analysis and evaluation method of time series ultrasonic signal using the attractor analysis. Features extracted from time series signal analyze quantitatively characteristics of welding defects. For this purpose, analysis objective in this study is fractal dimension and attractor Quadrant feature. Trajectory changes in the attractor indicated that even the same type of defects carried substantial difference in fractal characteristics resulting from distance shifts such as parts of head and flange. Such differences in characteristics of weld defects enables the evaluation of unique features of defects in the weld zone. In quantitative fractal feature extraction, feature values of 3.848 in the case of part of head(crack) and 4.102 in the case of part of web(side hale) and 3.711 in the case of part of flange(crack) were proposed on the basis of fractal dimensions. Proposed attractor feature extraction in this study can enhance the precision rate of ultrasonic evalaution for defect signals of rail weld zone such as side hole and crack.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.29-30
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• 2022

Tile defects in apartment houses are caused by a combination of various factors. These factors cannot be specified, and it is difficult to determine the exact cause because a number of causes are intertwined. In addition, because the climate of Korea is different by season, the coefficient of thermal expansion between materials is different, which is a major cause of tile defects. Therefore, this study analyzed the difference between the construction location and the period of defect occurrence according to the types of tile defects caused by environmental differences between indoor and outdoor environments. Two-way ANOVA was used, indoor and outdoor spaces were selected, and defect types were selected accordingly to show the difference in the occurrence period of each defect.

• Journal of Chest Surgery
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• 제19권2호
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• pp.232-237
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• 1986

The intraventricular conduction disturbances have been documented after correction of ventricular septal defects by any surgical route but debated its etiology. And so the frequency of conduction disturbances following right ventriculotomy, right atriotomy and pulmonary arteriotomy for closure of ventricular septal defects was compared in various conditions. The present series consists of 218 patients with ventricular septal defects. They had the surgical repair at the Seoul National University Hospital from January 1983 to October 1984. Conduction disturbances were studied with conventional 12 leads electrocardiogram. Of the 218 VSD`s 139 patients were repaired via vertical right ventriculotomy, 45 patients via right atriotomy, 34 patients via pulmonary arteriotomy. 1] Of 218 patients the frequency of RBBB was 26.1% and the frequency of RBBB + LAH was 6.0%. 2] There is no statistical difference between right ventriculotomy group [30.2%] and right atriotomy group [24.4%]. But there is significant difference between right ventriculotomy group and pulmonary arteriotomy group [11.8%] [P<0.05]. 3] In respect to anatomical classification by Kirklin`s method, the frequency of RBBB was higher in type II [32.1%] than in type I [14.9%]. [P<0.05] But in each anatomical type, there is no influence of the various surgical approach on the incidence of postoperative RBBB. 4] The frequency of RBBB was 31.8% in patch closure group and 14.3% in direct closure group. [P<0.05] Although the result suggests that there is no significant difference in various surgical approaches on the incidence of postoperative conduction disturbances, it may be reduced by a new-ventricular approach or a limited incision at right ventricular outflow tract in right ventricular approach.

• Archives of Reconstructive Microsurgery
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• 제8권2호
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• pp.139-148
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• 1999

Since Nakayama's first report about venous flap, many experimental and clinical studies were done about this new type of flap. And due to its various benefits, its applications as arterialized venous free flap type have increased recently. In this study we have attempted to reconstruct composite of defects of the hand with new modification of arterialized venous free flap and simultaneous reconstruction of skin, nerve, tendon were performed successfully. From 1994 to 1999, the defects of the hands in 35 patients were reconstructed with various modifications of arterialized venous free flaps. The range of age was from 19 to 55 years and size of flap ranged from $1{\times}2cm\;to\;14{\times}9cm$. Among them, 12 cases of flap over 20cm in size were included. Indications of flaps were as follows: resurfacing of the defects of the skin (9 cases), simultaneous reconstruction of extensor, skin and digital nerve(2 cases), reconstruction of the skin with extensor(5 cases), as a flap-through type vascular reconstruction(6 cases), for digital nerve reconstruction(2 cases), contracture release(3 cases), and finger tip reconstruction(9 cases). All of the cases except one survived with marginal skin necrosis less than 10%. And relatively large flaps over 20cm in size successfully survived without any delay procedures. Composite reconstructions including tendon and nerve were successful with new modifications of this flap. Arterialized venous free flap is one of the useful procedure in reconstruction of the hand because it has many advantages such as non-bulky and good quality of flap, variable length of pedicle, preservation of major vascular pedicle, less operation time, single operative field and in addition possibility of various modifications.

• 한국세라믹학회지
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• 제41권9호
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• pp.647-652
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• 2004

In aqueous tape casting of alumina slurry systems, the relationships between the suspension compositions and the defects of the dried tapes were discussed. The suspensions compositions were controlled with the ratios of the solids, water and organics binder contents. The effects of the thickness of dried tape and kinds of binder system were also examined. In the defect free region, the apparent viscosity showed nearly same value due to the count balancing effect of solid and organic binder content on the apparent viscosity. When water content was constant, increasing solid led to decrease of organic binder content. The defect free region was narrowed with increasing of casting thickness. When linear type acrylic emulsion binders system (D1000 and D 1035) were used, defect free zone formed the belt type in the triangle of solid, water and organic binder content according to the line of constant water contents. However the defect free region was not found in the cross-link type emulsion binder system (D 1050).

• 한국터널공학회:학술대회논문집
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• 한국터널공학회 2005년도 학술발표회 논문집
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• pp.292-298
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• 2005

Tunnel in subway should be designed as a water-proof type tunnel as much as possible but it is difficult to make it come true due to several facts, such as construction technique and cost. A drainage type tunnel as a substitute of a water-proof tunnel lead to the increase of water pressure on the concrete lining that make bad effect to tunnel structure when it has some problem to operate the drainage system. Throughout studying about cases on defects of tunnel drainage in subway We hope it contributes to tunnel maintenance.

• Journal of Chest Surgery
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• 제8권1호
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• pp.69-74
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• 1975

Twenty-nine cases of ventricular septal defect operated in this department during the period from 1969 to May 1975 were presented. Out of 29 cases, there were 20 cases of type II defects, 8 cases of type I, and one case of type III, and the last case was multiple defect. The anomalies associated with ventricular septal defect were eight in all; three patent ductus arteriosus, one atrial septal defect, one tricuspid insufficiency and an aortic insufficiency. Over all mortality was 17%. The causes of death were complete heart block in a case, respiratory distress due to excessive administration of morphine in one, low cardiac output in two and perforation of the aortic annulus after repair of the ventricular septal defect associated with aortic insufficiency.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.318-325
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• 2005

In present, KTX's wheel is worn inevitably according to the interaction with rail in service. It was analyzed by wearing type, damage type and wheel reprofiling cycle on the running surface. As a result, damage on the running surface is main cause to reprofile the wheel. Wearing type of wheel is normal and it hasn't reprofiled according to normal wheel wear. As a follow-up result of the whee] defects on the running surface, if the defects size is well managed by periodical inspection, it would be efficient to increase the wheel life.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.277-278
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• 2023

The need for maintenance of bridge infrastructure is increasing due to aging, and the cost of maintaining the infrastructure must be calculated for effective budget distribution. Therefore, in this study, representative defects according to bridge superstructure type are derived to calculate the cost for each repair method. First of all, the representative bridges, PSCI girder bridge, Rahmen bridge, Steel box girder bridge, and RC slab bridge, were selected as superstructures using BMS data, and repair methods for defects were presented. In addition, the cost of the repair method by superstructure type was compared. This result is expected to predict total maintenance costs in consideration of the maintenance cycle.