• The Korean Journal of Ceramics
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• 제4권2호
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• pp.151-155
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• 1998

The total electrical conductivity, ionic conductivity, and nonstoichimetry of a new cathode material $Y_{1-x}Ca_xFeO_{3-\delta}$ (x=0.1) were measured as functions of temperature ($900\leqT/^{\circ}C\leq1100$) and oxygen partial pressure $(10^{-6}\leqPo_2/atm\leq0.21$). Isothermal variations of these properties with $Po_2$ support that the majority type of ionic defects are anti-Frenkel disorder which, however, has seldom been considered for perovskite-based oxides. The results are discussed in comparison with those reported on similar oxides.

• Macromolecular Research
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• 제10권2호
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• pp.75-79
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• 2002

Organic materials have considerable attention as active semiconductors for device applications such as thin-film transistors (TFTs) and diodes. Pentacene is a p-type organic semiconducting material investigated for TFTs. In this paper, we reported the morphological and electrical characteristics of pentacene TFT films. The pentacene transistors showed the mobility of 0.8 $\textrm{cm}^2$/Vs and the grains larger than 1 ${\mu}{\textrm}{m}$. Deep-level transient spectroscopy (DLTS) measurements were carried out on metal/insulator/organic semiconductor structure devices that had a depletion region at the insulator/organic-semiconductor interface. The duration of the capacitance transient in DLTS signals was several ten of seconds in the pentacene, which was longer than that of inorganic semiconductors such as Si. Based on the DLTS characteristics, the energy levels of hole and electron traps for the pentacene films were approximately 0.24, 1.08, and 0.31 eV above Ev, and 0.69 eV below Ec.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.511-515
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• 2002

Extruded and cast plates of AZ type magnesium alloys were successfully joined by friction stir welding (FSW). Effect of FSW conditions on the formation of the defect was revealed in relation to tool rotation speed and specimen travel speed. Magnesium alloy with higher aluminum content became difficult to be joined and the optimum condition without defect was restricted into narrow condition range. The structure of the stirred zone was a fine-grained recrystallized structure even in the case of cast AZ91D. FSW joint had better mechanical properties than those of GTA welded joint. Especially the toughness of the stirred zone increased more than that of the base metal.

• Journal of Chest Surgery
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• 제10권1호
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• pp.106-112
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• 1977

Transposition of the great arteries is one of the commonest forms of severe congenital heart disease and produces severe cyanosis threatening survival from the day of birth. Anatomical anomalies which the aorta arises from the infundibulum of the right ventricle and the pulmonary artery arises from the outflow tract of the left ventricle make the deranged circulation. Survival is possible only if additional anomalies are present which allow mixing of the pulmonary and systemic circulations. Preoperative diagnosis as TGA was taken on the 15 day old female via the preoperative examination and the right cordioangiography. As palliative treatment for cyanosis, Blalock-Hanlon operation was performed in this patient. The results were good as 54 mmHg changed from 27 mmHg of $PO_2$ in aorta, but sudden cardiac arrest was developed in postoperative 12 hours. In order to confirm the cause of death and the cardiac anomalies, autopsy was performed on the date of death. The diagnosis of the autopsy showed; [1] Transposition of the Great Arteries. [2] Patent Ductus Arteriosus. [3] Patent Foramen Ovale. [4] Ventricular Septal Defect, 2 Muscular Type. [5] Double Ureter, Right. [6] Artificial Atrial Septal Defect. [7] Total Collapse of the left lung and Intraparenchymal hemorrhage of right lung.

• Advances in pediatric surgery
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• 제2권2호
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• pp.148-150
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• 1996

Transmesenteric hernia, a type of internal hernias, is a rare cause of intestinal obstruction. This intraperitoneal hernia has no sac and is formed by protrusion of a loop of bowel through an aperture in the mesentery. Incarceration leads to intestinal obstruction and subsequently, strangulation and gangrene of varing lengths of intestine. This is a case report of 4-year-old girl with transmesenteric herniation of the terminal ileum through a defect in its own mesentery. Strangulation of the affected bowel necessitates resection and primary anastomosis with repair of mesenteric defect. The postoperative course was uneventful. Acute intestinal obstruction in the absence of an external hernia and with no history of a previous surgical procedure suggests the possibility of an internal hernia, especially if the patient has a history of chronic intermittent abdominal distress.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.171-171
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• 2000

We have developed m innovative surface inspection system for automated quality control for steel products in POSCO. We had ever installed the various kinds of surface inspection systems, such as a linear CCD and a laser typed surface inspection systems at cold rolled strips production lines. But, these systems cannot fulfill the sufficient detection and classification rate, and real time processing performance. In order to increase detection and classification rate, we have used the Dark, Bright and Transition Field illumination and area type CCD camera, and fur the real time image processing, parallel computing has been used. In this paper, we introduced the automatic surface inspection system and real time image processing technique using the Object Detection, Defect Detection, Classification algorithms and its performance obtained at the production line.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 제7회 압연 심포지엄
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• pp.73-76
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• 2009

Increase in tensile strength of steel is important for fuel efficiency and $CO_2$ reduction. But the higher the strip strength, the more defect could be generated in hot strip mill. This study focuses on line-type edge scab. One of the causes for the defect is initial edge cracks commonly observed on a slab but their correlation has not been verified yet. Thus, the objective of this report is to verify if the edge crack is exactly the seed for edge scab. For this, we conducted pilot hot rolling test with cracked slab and compared the development of cracks and edge scabs on hot-rolled strip.

• 소성∙가공
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• 제8권5호
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• pp.491-497
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• 1999

The effect of partial squeeze on the quality of casting products in the vacuum die casting was investigated to make defect free casting products with excellent mechanical properties. The partial squeeze and vacuum die casting process was industrially implemented in making reaction shaft support which was made of a hypereutectic Al-15%Si alloy. To combine squeezing and vacuum effects, the plunger injection system was designed and attached on the chill vent type vacuum machinery system. The combination of vacuum effect before injection and partial squeezing effect after injection resulted in defect free die casting products. The uniform distribution of fine eutectic and proeutectic Si obtained from trial process also provided excellent mechanical properties.

• Journal of Chest Surgery
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• 제16권2호
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• pp.164-169
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• 1983

The patient in whom corrected transposition of the great vessels is an isolated congenital anomaly has a physiologically normal circulation. A 19 year old male was perforemd with surgical correction for congenitally corrected transposition of great arteries (SLL) associated with ventricular septal defect (type I) and severe pulmonary stenosis. After right sided ventriculotomy, ventricular septal defect was repaired with Dacron patch and to provide adequate relief of severe valvar stenosis of pulmonary artery, valvulotomy was done. On immediate postoperative period, complete heart block and lower cardiac output state were ocurred, but adequate blood pressure could be maintained under using of inotropic agent and temporary pace-maker.

• Journal of Chest Surgery
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• 제21권1호
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• pp.82-86
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• 1988

Tetralogy of Fallot with subarterial ventricular septal defect is known to be relatively common in the Far East. Among the 140 consecutive patients who underwent repair for tetralogy, 15 [10,7@] had this variant form of tetralogy. Though the degree of pulmonic stenosis seems only mild or moderately severe because of the absence of infundibular septum and relatively large size of pulmonary arteries in this type of tetralogy, it has a special surgical implication that a patch widening of the right ventriculotomy is necessary in every case to avoid the postoperative subpulmonic stenosis. A morphological and surgical features of tetralogy with subarterial VSD are presented.