• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2089-2098
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• 2015

With the continuous development in insulation of electrical equipment design, the reliability of the system has been enhanced. However, in the manufacturing process and during operation under continues stresses introduce local defects, such as voids between interfaces that can responsible to occurrence of partial discharge (PD), electric field distortion and accumulation of charges. These defects may lead to localize corrosion and material degradation of insulation system, and a serious threat to the equipment. A model of three layers of PI film with air gap is presented to understand the influence of interface and voids on exploitation conditions such as strong electrical field, PD activity and charge movement. The analytical analysis, and experimental results are good agreement and show that the lose contact between interfaces accumulate more residual charges and in consequences increase the electric field intensity and accelerates internal discharges. These residual charges are trapped charges, injected by the electrodes has often same polarity, so the electric field in cavities increases significantly and thus partial discharge inception voltage (PDIV) decreases. Contrary, number of PD discharge quantity increases due to interface. Interfacial polarization effect has opposite impact on electric field and PDIV as compare to void.

• Journal of Biomedical Engineering Research
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• v.32 no.1
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• pp.32-36
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• 2011

The insufflators in endoscopic surgery supply carbon dioxide to make the air-filled cavity in the abdomen. It contains many kinds of pneumatic and electronic parts and they are connected with the air tubes and electrical wires. The printed circuit boards (PCB) perform wiring, holding and cooling tasks in electronic systems. In this study, the PCB is used as the air channel for insufflators to decrease the cost, volume, and the malfunction according to aging of the device. Three layers of PCB made of FR4 are combined with prepreg as adhesive which has the internal airway channel according to the design. By mounting the pressure sensors and valves, the PCB based fluidic system is implemented. After calibration of flow sensor, the flow rate of the gas also can be measured. The climate test, temperature test, and biocompatibility test showed this idea can be used in insufflators for laparoscopic surgery.

• Journal of Veterinary Clinics
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• v.26 no.1
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• pp.81-85
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• 2009

A spayed female, 8-year-old, maltese, weighing 1.84 kg with a history of acute severe vomiting, anorexia, depression for 2 day was referred. An abdominal mass was palpated with abdominal pain on physical examination. Radiographic findings included two soft tissue density masses in the mid-abdominal cavity and gas dilated colon. Ultrasonographs showed one heterogeneous hypoechoic round mass including intestinal wall. There were loss of normal wall layering and motility and absence of internal lumen of the intestinal wall. And another heterogeneous hyperechoic mass was identified to the medial side of the intestinal mass. Based on clinical signs, image findings, and the result of fine needle aspiration, intestinal obstruction due to alimentary lymphoma was diagnosed. On surgery, a cecal lymphoma and mesenteric lymphadenopathy were confirmed and the cecal mass was resected.

• Korean Journal of Veterinary Research
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• v.48 no.3
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• pp.323-326
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• 2008

A two-year-old mixed breed sow was requested to the Veterinary Pathology Laboratory of Cheju National University with a clinical signs of severe abdominal pain and sudden death. Grossly, there was severe hemorrhage in abdominal cavity. Most of internal parenchymas and subcutaneous muscle showed severe pale discoloration. Both ovaries were enlarged with oval to round protruding multilobular masses and dark red in color. And they were firm and contained multiple small cysts in their cut surface. Histopathologically, numerous neoplastic granulosa cells had spherical-to-oval, hyperchromatic nuclei and scant eosinophilic cytoplasms were distributed with follicular pattern in ovarian masses. And the typical Call-Exner bodies, distinctive microcavityies, were observed in the center of small neoplastic follicles. Based on the gross and histopathologic findings, this case was diagnosed as granulosa cell tumor. In our best knowledge, this is believed to be the first report of granulosa cell tumor in a sow in Korea.

• Journal of Trauma and Injury
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• v.23 no.1
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• pp.49-52
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• 2010

A hemothorax usually occur, due to injuries to the intercostal and great vessels, pulmonary damage, and sometimes fractured ribs. We report a case in which the hemothorax that occurred, neither intrathoracic injury nor injury to internal thoracic vessels and organs, via lacerated diaphragmatic and liver laceration due to a right upper part of anterior chest stab injury caused by a sharp object. The patient's general conditions gradually worsened, so chest and abdominal computed tomogram were taken. The abdominal computed tomogram revealed diaphragmatic injuries and bleeding from the lacerated liver. We performed an exploratory laparotomy to control the bleeding from the lacerated liver with simple primary sutures. In addition exploration was performed in the right pleural space through the lacerated diaphragm with a thoracoscopic instrument. There were no bleeding foci in the right pleural space, the vessels, or the lung on the thoracoscopic video. Closure of the lacerated diaphragm was achieved with simple, primary sutures. The postoperative course of the patient was uneventful, and the patient was discharged.

• Journal of the Optical Society of Korea
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• v.16 no.1
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• pp.22-28
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• 2012

We report a focal-length tunable liquid lens based on thermopneumatically driven fluidic pressure. The fluidic pressure is generated by deformation of an elastomeric diaphragm induced by thermopneumaticity from a laterally integrated microheater sealed within an air chamber. The pressure is transmitted by a confined liquid to a lens diaphragm through an internal fluid channel. The liquid filling under the lens diaphragm functions as a liquid lens for dynamic focusing with properties depending on the curvature of the deformed diaphragm. The diaphragm area of the air chamber is designed five times larger than that of the lens cavity to yield high focal-length tunability by amplified deflection of the lens diaphragm. With our method, we achieved excellent focal-length tunability from infinity (without an input current) to 4 mm (with an input current of 12 mA) with a lens aperture diameter of 2 mm.

• Advances in pediatric surgery
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• v.1 no.1
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• pp.59-62
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• 1995

Meconium peritonitis is defined as an aseptic, chemical or foreign-body peritonitis caused by spill of meconium in the abdominal cavity related to the prenatal perforation of the intestine. Perforation is usually caused by obstruction from meconium ileus, intestinal atresia, stenosis, volvulus, internal hernia, congenital peritoneal bands, intussusception, or gastroschisis. Less commonly, no evidence of distal obstruction exists. Here, we present two cases of generalized meconium peritonitis of antenatal diagnosis. The first case, detected at 8 months of gestational age, had a perforation of the proximal blind pouch of jejunal atresia, associated with respiratory distress due to severe abdominal distension. This case was successfully treated with resection and anastomosis and brief period of postoperative ventilatory support. The second case had a distal ileal perforation with thick meconium in the terminal ileum. In this case, there was no dilatation of ileum proximal to the perforation site. Resection and anastomosis was performed and postoperative course was uneventful.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.06a
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• pp.93-98
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• 2006

Warm forming technology was classified into hot gas forming of using compressible fluid as a nitrogen gas and warm hydroforming of using the incompressible fluid as a thermal oil by using medium fluid. In this study, the aluminum side-rail part was developed with warm hydroforming technology. For the warm hydroforming system, top and bottom die was designed to insert heating cartridge in die cavity and special indirect fluid heating system was designed to heat the thermal oil. As increase the temperature, hydroformability was increased linearly. Aluminum side-rail center part was formed 90% at the internal pressure of 100bar and perfectly formed at 300bar within a moderate temperature. The tube material used for warm hydroforming was a aluminum 6000 series alloy with the diameter of 120mm, thickness of 5mm, length of 1,300mm. Warm hydroformed side-rail center part had 20% of maximum expansion ratio and below 20% of maximum thinning ratio at corner radius. This results were provided to show warm hydroforming possibility for aluminum automotive components.

• Journal of Chest Surgery
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• v.43 no.5
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• pp.553-556
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• 2010

A 55-year-old female presented to Pusan National University Yangsan Hospital with left neck and shoulder pain. An anterior mediastinal mass was detected on chest CT and there were no other specific lesions in the lung or pleural cavity. An infected pericardial cysts was suspected and excision was performed through a left-sided VATS approach. The patient was discharged on the second post-operative day with left diaphragm palsy and praziquantel was prescribed after paragonimaisis was confirmed on pathology. The patient has not shown any particular problems at my outpatient clinic.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.3
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• pp.174-177
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• 2013

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a disease characterized by jaw necrosis and delayed wound healing in patients who had received bisphosphonates. Buccal fat pad (BFP) can be used as a pedicled flap in the posterior region of the oral cavity. BFP pedicle flap needs simple surgical technique and it shows less donor site morbidity and aesthetic problem than other vascularized flap. BFP pedicled flap was fed by 3 arteries-facial, internal maxillary, and transverse facial artery. Osteomyelitis was generally related with poor blood supply. Thus, rich blood supply of BFP pedicle flap can have a potential advantage to BRONJ patients. In this case report, we presented 3 BRONJ patients treated by BFP pedicle flap after sequestrectomy.