• Journal of Chest Surgery
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• v.22 no.1
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• pp.95-105
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• 1989

The records of 248 patients over 16 years of age who had undergone a surgical correction of a congenital cardiovascular malformation during the period of 10 years from August, 1978 to July, 1988 were reviewed. During this period, the incidence of congenital cardiovascular malformation in adult was 18.2% of 1376 total heart disease operated on and 25.5% of 986 congenital heart defects. Among them, there were 200 patients in acyanotic group and 48 patients in cyanotic group. Male versus female ratio was 1:1.28. The oldest patient was 59 years old female who had atrial septal defect. The mean age was 24.4 years old. The distribution of the lesions showed a large preponderance of atrial septal defects [37.19o] followed in frequency by ventricular septal defects [918.1%], patent ductus arteriosus [17.3%], tetralogy of Fallot [16.1%], and a variety of other complex malformations[3.2%]. In the pediatric age group, relative frequency was different from that of this adult group, showing ventricular septal defects, tetralogy of Fallot, patent ductus arteriosus and atrial septal defects in order of incidence. The hospital mortality and late mortality were 6.0% and 1.7% respectively. The causes of hospital death were low cardiac output in 10 patients, arrhythmia in 2, air embolism in 1, sepsis in 1 and respiratory failure in l. Clinical improvement upto NYHA functional class I or II postoperatively has been achieved and sustained in all patients following repair except the patients of late death and receiving reoperation. This result confirms that congenital heart defects in the adults can be corrected with a good outcome and an aggressive operative approach seems justified.

• Structural Engineering and Mechanics
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• v.84 no.3
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• pp.337-344
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• 2022

Due to corrosion defects on the surface of the oil pipe, the sealing performance of the annular blowout preventer (BOP) decreases, and the leakage of toxic and harmful gases such as H₂S and SO₂ will threaten the safety of operators on the well. Therefore, this paper establishes the FE model for evaluating the sealing performance of BOP-oil pipe corrosion defects, which is based on the rubber large deformation theory and rubber core sealing mechanism, and designs the experiment of BOP sealing performance to verify the accuracy of the FE model. The sealing performance of BOP sealing oil pipe with corrosion defects is studied. The research results show that the sealing performance of BOP is more sensitive to the axial size of corrosion defects. With the increase of oil pipe outer diameter, the critical size of defects increases continuously. The sensitivity of radial and depth dimensions is low, When for 88.9 mm outer diameter oil pipe, the axial critical size of corrosion defect is 20 mm, the radial critical size is 16 mm and the critical depth is 2 mm. Fit the formula between the outer diameter of oil pipe and the piston increment. According to the formula, the operator can calculate the piston stroke increment required by the BOP to complete the sealing when the oil pipe is corroded.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.95-97
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• 2007

Large area flicker is one of the most annoying image defects, and it is an inherent characteristic of impulsively driven displays such as CRTs. Recently, LCDs have also adopted impulsive driving methods for improved motion picture quality, therefore LCDs can also show large area flicker. Existing metrics do not account for the non-linearity of human brightness perception. This paper presents an improved large area flicker metric to more accurately quantify large area display flicker performance.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.197-198
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• 2008

The forging process produces complicated and designed components in a die at high productivity for mass production and minimizes the machining amount for favorable material utilization; the forging products used at highly stressed sections are well accepted at a wide range of industry such as automobile, aerospace, electric appliance and et cetera. Accordingly, recent R&D activities have been emphasized on improvement of forging die-life and near net shaping technology for cost effectiveness and better performance. Usually closing and consolidation of internal void defects in a ingot is a vital matter when utilized as large forged products. It is important to develop cogging process for improvement of internal soundness without a void defect and cost reduction by solid forging alone with limited press capacity. For experiments of cogging process, hydraulic press with a capacity of 800 ton was used together with a small manipulator which was made for rotation and overlapping of a billet. Size of a void was categorized into two types; ${\phi}$ 6.0 mm and ${\phi}$ 9.0 mm to investigate the change of closing and consolidation of void defects existed in the large ingot during the cogging process. In addition for forming experiment of piston grown air drop hammer with a capacity of 16 ton was used. The experiment with piston crown was carried out to show the formability and void closing status. In this paper systematic configuration for closing process of void defects were expressed based on this experiment results in the cogging process. Also forging defects through forming process for piston crown was improved using the experiment results and FE analysis. Consequently this paper deals with the effect of radial parameters in cogging process on a void closure far large forged products and formability of piston crown.

• Archives of Craniofacial Surgery
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• v.20 no.1
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• pp.17-23
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• 2019

Background: The resection of head and neck cancer can result in postoperative defect. Many patients have difficulty swallowing and masticating, and some have difficulty speaking. Various types of flaps are used for palatal reconstruction, but flap selection remains controversial. Therefore, our study will suggest which flap to choose during palatal reconstruction. Methods: Thirteen patients who underwent palatal reconstruction from 30 January, 1989 to 4 October, 2016 at our institution. Size was classified as small when the width was < $4cm^2$, medium when it was $4-6cm^2$, and large when it was ${\geq}6cm^2$. Based on speech evaluation, the subjects were divided into a normal group and an easily understood group. After surgery, we assessed whether flap selection was appropriate through the evaluation of flap success, complications, and speech evaluation. Results: Defect size ranged from $1.5{\times}2.0cm$ to $5.0{\times}6.0cm$. In four cases, the defect was in the anterior third of the palate, in eight cases it was in the middle, and there was one case of whole palatal defect. There were three small defects, two medium-sized defects, and eight large defects. Latissimus dorsi free flaps were used in six of the eight large defects in the study. Conclusion: The key to successful reconstructive surgery is appropriate selection of the flap with reference to the characteristics of the defect. Depending on the size and location of the defect, the profiles of different flaps should be matched with the recipient from the outset.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.16 no.2
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• pp.1-9
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• 2020

Large-scale industrial facility structures continue to deteriorate due to the effects of operating and environmental conditions. The problems of these industrial facilities are potentially causing economic losses, environmental pollution, casualties, and national losses. Accordingly, in order to prevent disaster accidents of large structures in advance, the necessity of diagnosing structures using non-destructive inspection techniques is being highlighted. The defect occurrence, location and defect type of the structure are important parameters for predicting the remaining life of the structure, so continuous defect observation is very important. Recently, many researchers have been actively researching real-time monitoring technology to solve these problems. Structure Health Monitoring Inspection is a technology that can identify and respond to the occurrence of defects in real time, but there is a limit to check the degree of defects and the direction of growth of defects. In order to compensate for the shortcomings of these technologies, the importance of defect imaging techniques is emerging, and in order to find defects in large structures, a method of inspecting a wide range using guided ultrasonic is effective. The work presented here introduces a calculation for the shape factor for evaluation of the damaged area, as well as a variable β parameter technique to correct a damaged shape. Also, we perform research in modeling simulation and an experiment for comparison with a suggested inspection method and verify its validity. The curved structure image obtained by the advanced RAPID algorithm showed a good match between the defect area and the shape.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3342-3351
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• 2023

High-density polyethylene (HDPE) pipelines in nuclear power plants (NPPs) have to meet high requirements for seismic performance. HDPE pipes have been proved to have good seismic performance, but joints are the weak links in the pipelines, and pipeline failures usually initiate from the defects inside the joints. Limited data are available on the seismic performance of butt-fusion joints of HDPE pipelines in NPPs, especially in terms of defects changes inside the joints after earthquakes. In this paper, full-scale shaking table tests were performed on a test section of suspended HDPE pipelines in an NPP, which included straight pipes, elbows, and 10 butt-fusion joints. During the tests, the seismic load-induced strain of the joints was analyzed by strain gauges, and it was much smaller than the internal pressure and self-weight-induced strain. Before and after the shaking table tests, phased array ultrasonic testing (PA-UT) was conducted to detect defects inside the joints. The locations, numbers, and dimensions of the defects were analyzed. It was found that defects were more likely to occur in elbows joints. No new defect was observed after the shaking table tests, and the defects showed no significant growth, indicating the satisfactory seismic performance of the butt-fusion joints.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.1
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• pp.1-16
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• 1996

There are various defects caused by trauma or resection of maignant tumor in the orofacial region, which can be reconstructed with various regional and pararegional flaps. Among these defects, it is very difficult to reconstruct palatal and midfacial defects after maxillectomy and patients have problems in speaking and swallowing of food. Therefore it is very important for surgeons to reconstruct these defects functionally and esthetically and to return the patients to the normal social activity. These defects are usually obturated with prosthodontic appliances to assist the phonation and swallowing. But nowadays surgical reconstruction by various flaps was considered and performed for better rehabilitation. For this purpose the forehead flap, the nasolabial flap, the tongue flap, the sternocleidomastoideous flap, the temporal flap, the latissimus dorsi flap, the scapular flap etc. are used. We reconstructed small-sized plalatal defects with tongue flap, medium-sized palatal and maxillary defects after maxillectomy with temporal myofascial flap and large midfacial defects including eyeball exenteration with latissimus dorsi myocutaneous flaps. Here we are to report 5 cases of these flaps used for the reconstruction of palatal and midfacial defects and consider the versatility, reliability and limitation in use of these flaps.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.580-582
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• 2004

As the demand of large and high-resolution display panels is increased, the black light units (BLU) of the display devices play an important roles. In this study we'll deal with various defects of BLUs. Patterns of defects can be classified by the scratches, the non-uniform misprinting for the diffused reflection, the surface stains, spots and etc. Due to these distorted patterns the high-resolution and high-precision could be impeded. We'll propose the visual inspection system to detect various defects by pattern-matching.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.130-134
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• 1997

The structural defects, impurities, degree of crosslinking and shrinkage of 38 field-aged distribution cables have been analyzed. For the comparison of data, 9 new cables were also subjected to an analysis. It is observed that the structural defects and degree of crosslinking show a radial profile. The structural defects are different depending on the manufacturer. A large amount of impurities is present in the insulation shield, which hold true for the new cables manufactured recently. The degree of crosslinking near both shields is lower than that at the central region of the insulation layer. It was also found that, in some cal)toes, the ins난lation was not fully crosslinked. The shrinkage of field-aged cables is higher than that of new cables.