• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.6
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• pp.749-757
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• 1999

Holographic interferornetric tomography can provide reconstruction of instantaneous three dimensional gross flow fields. The technique however confronts ill-posed reconstruction problems in practical applications. Experimental data are usually limited in projection and angular scanning when a field is captured instantaneously or under the obstruction of test models and test section enclosures. An algorithm, based on a series expansion method, has been developed to improve the reconstruction under the ill-posed conditions. A three-dimensional natural convection flow around two interacting isothermal cubes is experimentally investigated. The flow can provide a challenging reconstruction problem and lend itself to accurate numerical solution for comparison. The refractive index fields at two horizontal sections of the thermal plume with and without an opaque object are reconstructed at a limited view angle of 80" The experimental reconstructions are then compared with those from numerical calculation and thermocouple thermometry. It confirms that the technique is applicable to reconstruction of reasonably complex, three-dimensional flow fields.elds.

• Tuberculosis and Respiratory Diseases
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• v.78 no.2
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• pp.128-132
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• 2015

Bronchopulmonary dysplasia (BPD) is related to decreased lung function throughout life. However, the pathology and radiology pattern of BPD of adults are not documented well yet. In this case report, we present BPD case of an adult monozygotic twin showing nearly identical lesions on chest computed tomography (CT). CT images showed mixed areas of ground-glass and reticular opacities in both lungs. They had common histories of pneumonias requiring mechanical ventilations in period of infants. Pulmonary function test of one patient showed a pulmonary insufficiency with airway obstruction. Pathologic findings showed bronchiolar hyperplasia and peribronchiolar fibrosis which was similar to classic BPD patients. Our twin case report might help provide distinguishing pathology and radiology pattern of an adult pulmonary sequelaes of BPD. It might be reasonable to make close follow-up for BPD patients to evaluate the long-term outcomes of BPD survivors.

• Journal of information and communication convergence engineering
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• v.19 no.2
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• pp.108-113
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• 2021

Multiview autostereoscopic three-dimensional (MA3D) displays have the disadvantage that the single-view resolution decreases as the number of views increases. Furthermore, the resolution of MA3D displays is relatively degraded, even though the resolution of two-dimensional displays has increased recently. Therefore, it is unattractive to consumers, and the single-view resolution enhancement of MA3D displays is required. In this study, we developed a method for supplementing the single-view resolution of MA3D displays using a plate beam splitter that can show two MA3D displays simultaneously. By applying our proposed method, the resolution of a single view can increase, and the visual obstruction by the optical plate, which is a problem for MA3D displays, can be solved. In addition, an MA3D display was optically designed and fabricated using a parallax barrier. Finally, the experimental optical results obtained using the proposed method and the only MA3D display were compared.

• Tuberculosis and Respiratory Diseases
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• v.62 no.5
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• pp.437-440
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• 2007

Tracheostomy is one of the oldest surgical procedures in medical history. The indications for a tracheostomy include the relief of an upper airway obstruction, long-term mechanical ventilation, and decreased airway resistance to help wean the patient from mechanical ventilator support. Unfortunately, tracheostomy is also associated with a number of problems including, bleeding, infection, pneumothorax, and tracheal stenosis. A pneumothorax is an uncommon complication of a tracheostomy, and can result from direct injury to the pleura or positive pressure ventilation through a dislocation of the tracheostomy tube. We report an uncommon case of a tracheostomy-induced bilateral tension pneumothorax with a review of the literature.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.1
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• pp.53-62
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• 1991

Tracheostomy may be used to assure airway protection in various clinical situation. It, as a known operation, has a history spanning 2000 years. The first clear account of a successful tracheostomy was recorded in 1546 by Brasavola. Until 1718 the term "bronchotomy" was used to describe the procedure. Heister then introduce the term "tracheotomy and this was later adopted and popularized by Trousseau about 1830. The term "tracheostomy" appeared in medical literature after 1820 and the two terms "tracheostomy" and "tracheotomy" are used interchangeably today. Indications include relief of upper airway obstruction, facilitation of pulmonary toilet, diminution of dead space and need for prolonged mechanical ventilation. The extent of indication of tracheostomy has a tendency to increase, thus oral and maxillofacial surgeons have some opportunities to face a situation that require tracheostomy. So, we reported retrospective study of 31 cases of tracheostomy patient in oral and maxillofacial surgery with reference review to reveal the significance of surgical skill and management capability of emergercy state maxillofacial surgery patients.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.455-462
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• 2016

Recently, followed by rapid growth of robotics field, multi-linkage mechanism which can even pass by rough road is getting lots of attention. In this paper, I focused on Jansen mechanism. It's a kinematics object which is named after Dutch artist Theo jansen. Jansen mechanism embraces structure and mechanism which creates locomotion with the combination of the power and simple structure. Theo jansen suggests a 'Holy number'. It's an ideal ratio of leg components length. However, if there's desired gait locomotion, you have to adjust the ratio and the length. But even slight change of the length could cause a big change at the end-point. To solve this problem, I suggest a reverse engineering method to get a ratio of each links by nonlinear optimization with pre-set desired trajectory. First, we converted a movement of the joint of Jansen mechanism to vectors by kinematics analysis of multi-linkage structure. And we showed the trajectory at the end-point. After that, we set desired trajectory which we found most ideal. Then we got the length of the leg components which draws a trajectory as same as trajectory we set, using Multi-objective genetic algorithm toolbox in MATLAB. Result is verified by Edison designer and mSketch. And we analyzed if it could pass through the obstruction which is set dynamically.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.766-770
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• 2008

Primary tumors of the heart are uncommon among pediatric patients. Rhabdomyoma is the most frequent cardiac tumor in infants and children, which is commonly associated with tuberous sclerosis. Tuberous sclerosis is a neurocutaneous syndrome affecting the brain, heart, skin, and other organs. Cardiac rhadomyomas are reported in 50-64% of infants with tuberous sclerosis. Tuberous sclerosis involves multiple locations in the atrium, ventricle and septum, and may induce mechanical obstruction of the outflow tract and heart failure depending on the location, number, size, and degree of invasion of tumors. Arrhythmias may also develop in infants with cardiac rhadomyomas, but only a few of these patients require prolonged anti-arrhythmic therapy because arrhythmia often disappears with spontaneous regression of the tumors, and the ultimate prognosis may be decided by the cerebral manifestations.

• Clinical and Experimental Pediatrics
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• v.58 no.4
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• pp.154-157
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• 2015

Plastibell is one of the three most common devices used for neonatal circumcision in the United States, with a complication rate as low as 1.8%. The Plastibell circumcision device is commonly used under local anesthesia for religious circumcision in male neonates, because of cosmetic reasons and ease of use. Occasionally, instead of falling off, the device may get buried under the skin along the shaft of the penis, thereby obstructing the normal flow of urine. Furthermore, the foreskin of neonates is highly vascularized, and hence, hemorrhage and infection are possible when the skin is cut. Necrosis of penile skin, followed by urethral obstruction and renal failure, is a serious surgical mishap requiring immediate corrective surgery and medical attention. We report a case of fulminant urosepsis, acute renal failure, and pyelonephritis in a 4-day-old male neonate secondary to impaction of a Plastibell circumcision device. Immediate medical management was initiated with fluid resuscitation and mechanical ventilation; thereby correcting life threatening complications. Pediatricians and Emergency Department physicians should be cognizant of the complications from Plastibell circumcision device in order to institute appropriate and timely management in neonates.

• Journal of Powder Materials
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• v.23 no.3
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• pp.247-253
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• 2016

In this study, solid solution heat treatment of consolidated nickel-based superalloy powders is carried out by hot isotactic pressing. The effects of the cooling rate of salt quenching, and air cooling on the microstructures and the mechanical properties of the specimens are analyzed. The specimen that is air cooled shows the formation of serrated grain boundaries due to their obstruction by the carbide particles. Moreover, the specimen that is salt quenched shows higher strength than the one that is air cooled due to the presence of fine and close-packed tertiary gamma prime phase. The tensile elongation at high temperatures improves due to the presence of grain boundary serrations in the specimen that is air cooled. On the contrary, the specimen that is salt quenched and consists of unserrated grain boundaries shows better creep properties than the air cooled specimen with the serrated grain boundaries, due to the negative creep phenomenon.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.4
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• pp.664-668
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• 1999

Mucocele is clinical term used to describe swelling caused by the pooling of saliva at the site of a severed or obstructed minor salivary gland duct. Mucoceles are categorized into two subgroups, extravasation type and retention cyst type. The etiology of extravasation type mucocele is related to mechanical trauma to the minor salivary gland excretory duct, resulting in extravasation of mucus into the fibrous connective tissue so that a cyst-like cavity is produced, but the epithelial lining is absent. Retention cyst type mucocele results from obstruction of minor salivary gland excretory duct, and cystic cavity is lined by epithelial cells. This case report presents a mucocele occurred on the lower lip, and caused by suture silk unremoved for 3 years. Suture silk penetrated and tore the minor salivary gland duct on the lower lip with subsequent extravasation of mucus into the fibrous connective tissue.