• Wind and Structures
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• v.16 no.1
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• pp.93-115
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• 2013

This paper describes a study of the influence of a dynamically flexible building structure on pressures inside and net pressures on the roof of low-rise buildings with a dominant opening. It is shown that dynamic interaction between the flexible roof and the internal pressure results in a coupled system that is similar to a two-degree-of-freedom mechanical system consisting of two mass-spring-damper systems with excitation forces acting on both the masses. Two resonant modes are present, the natural frequencies of which can readily be obtained from the model. As observed with quasi-static building flexibility, the effect of increased dynamic flexibility is to reduce the first natural frequency as well as the corresponding peak value of the admittance, the latter being the result of increased damping effects. Consequently, it is found that the internal and net roof pressure fluctuations (RMS coefficients) are also reduced with dynamic flexibility. This model has been validated from experiments conducted using a cylindrical model with a leeward end flexible diaphragm, whereby good match between predicted and measured natural frequencies, and trends in peak admittances and RMS responses with flexibility, were obtained. Furthermore, since significant differences exist between internal and net roof pressure responses obtained from the dynamic flexibility model and those obtained from the quasi-static flexibility model, it is concluded that the quasi-static flexibility assumption may not be applicable to dynamically flexible buildings. Additionally, since sensitivity analyses reveal that the responses are sensitive to both the opening loss coefficient and the roof damping ratio, careful estimates should therefore be made to these parameters first, if predictions from such models are to have significance to real buildings.

• Journal of Veterinary Clinics
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• v.23 no.4
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• pp.461-464
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• 2006

Perineal hernia occurs spontaneously in older male dogs after idiopathic weakening of the pelvic diaphragm A 14-year-old uncastrated male shih tzu dog with right-sided perineal swelling was referred to the Veterinary Medical Teaching Hospital of Konkuk University. He had sign of perineal swelling for three years. Plain radiography documented the extent of rectal and colonic dilation in the herinal sac. During surgery, external anal sphincter muscle, coccygeus muscle and levator am muscle were weakened due to the three years of herniation. Internal obturator muscle transposition method was not enough for large defect, so mesh was applied to reduce the hernial sac. Internal obturator muscle transposition combined with using of polypropylene mesh was successfully performed in this dog.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.494-503
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• 1994

Background: Fibrostenosis of large airway due to tuberculosis is one of the most perplexing clinical problems not only because it can lead to respiratory failure but also because of difficulty in the management. No one technique, such as balloon dilatation or insertion of self expandable metallic stent, has proved totally satisfactory in the management of fibrostenosis. We evaluated the effect of laser therapy in patient with severe fibrostenosis due to tuberculosis. Method: We classified the fibrostenosis to three types by bronchoscopic finding - the diaphragm type: stenosed by fibrous diaphragm, sparing the tracheobronchial wall, the collapse type: stenosed by collapse of the wall due to destruction of the cartilage, and the combined type: stenosed by nonspecific inflammatory scar tissue within internal lumen with collapse of the wall. We have treated 10 patients complaining dyspnea due to with severe fibrostenosis of the diaphargm or the combined type using a neodymiumyttrium aluminum garnet(Nd-Y AG) laser through a flexible bronchoscopy. Results: Eight of the 10 cases improved after laser therapy and maintained during a follow up period of average 31.9 months. All of the cases undergoing laser therapy showed no serious complication to need the therapy. Conclusion: The results of our present study indicate that the Nd-YAG laser therapy is an effective and safe method for the management of selective tuberculous fibrostenosis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05e
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• pp.108-111
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• 2003

The main objective of this paper is to module design and pressure relief test a new type of polymer gapless surge arrester for power distribution line. Metal oxide surge arrester for most electric power system applications, power distribution line and electric train are now being used extensively to protect overvoltage due to lightning. Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit current. When breakdown of gapless elements in a surge arrester occurs due to flashover, fault short current flows through the arrester and internal pressure of the arrester rises. The pressure rise can usually be limited by fitting a pressure relief diaphragm and transferring the arc from the inside to the outside of the housing. However, there is possibility of porcelain fragmentation caused by the thermal shock, pressure rise, etc. Non-fragmenting of the housing is the most desired way to prevent damage to other equipment. The pressure change which is occurred by flashover become discharge energy. This discharge energy raises to damage arrester housing and arrester housing is dispersed as small fragment. Therefore, the pressure relief design is requested to obstruct housing dispersion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.175-179
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• 2005

The main objective of this paper is to module design and pressure relief test a new type of polymer gapless surge arrester for power distribution line. Metal oxide surge arrester for most electric power system applications, power distribution line and electric train are now being used extensively to protect overvoltage due to lightning. Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit current. When breakdown of gapless elements in a surge arrester occurs due to flashover, fault short current flows through the arrester and internal pressure of the arrester rises. The pressure rise can usually be limited by fitting a pressure relief diaphragm and transferring the arc from the inside to the outside of the housing. However, there is possibility of porcelain fragmentation caused by the thermal shock, pressure rise, etc. Non-fragmenting of the housing is the most desired way to prevent damage to other equipment. The pressure change which is occurred by flashover become discharge energy. This discharge energy raises to damage arrester housing and arrester housing is dispersed as small fragment. Therefore, the pressure relief design is requested to obstruct housing dispersion.

• Journal of Korean Society of Steel Construction
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• v.18 no.1
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• pp.23-32
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• 2006

This study was conducted to improve the design and construction technique of orthotropic steel-deck bridges. After conducting an F.E.M. analysis of the various rib types of the connection details, static and fatigue tests were conducted, using a three-dimensional, full-scaled, orthotropic, steel-deck-plate model with internal diaphrams, to check the fatigue strength depending on the types of details. The model structure was made of two types of longitudinal ribs: the domestic standard and the European rabbit types. The fatigue strength of the steel-deck system was found to have improved through the installation of an internal diaphram, as no cracks were found on the bottom round part of the scallop with a diaphram. There were no differences between the domestic and the European types of details in terms of strength may be partially influenced by the shape of the scallop and by the installation of an internal diaphram, but it can be improved more significantly according to the quality of the welding that will be done.

• The Korean Journal of Nuclear Medicine
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• v.24 no.2
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• pp.279-285
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• 1990

Simultaneous presence of ascites and pleural effusion has been documented in patients with cirrhosis of the liver, renal disease, Meigs' syndrome and in patients undergoing peritoneal dialysis. Mechanisms proposed in the formation of pleural effusion in most of the above diseases are lymphatic drainage and diaphragmatic defect. But sometimes, hepatic hydrothoraxes in the absence of clinical ascites and pleural effusion secondary to pulmonary or cardiac disease are noted. It is not always possible to differentiate between pleural effusion caused by transdiaphragmatic migration of ascites and by other causes based soly on biochemical analysis. Authors performed radionuclide scintigraphy after intraperitoneal administration of $^{99m}Tc-labeled$ colloid in 23 patients with both ascites and pleural effusion in order to discriminate causative mechanisms responsible for pleural effusion. Scintigraphy demonstrated the transdiaphragmatic flow of fluid from the peritoneum to pleural cavities in 13 patients correctly. In contrast, in 5 patients with pleural effusion secondary to pulmonary, pleural and cardiac diseases, radiotracers fail to traverse the diaphragm and localize in the pleural space. Ascites draining to mediastinal lymph nodes and blocked passage of lymphatic drainage were also clarified, additionaly. Conclusively, radionuclide peritoneal scintigraphy is an accurate, rapid and easy diagnostic tool in patients with both ascites and pleural effusion. It enables the causes of pleural effusion to be elucidated, as well as providing valuable information required when determining the appropriate therapy.

• Tuberculosis and Respiratory Diseases
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• v.64 no.1
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• pp.39-43
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• 2008

A hiccup is caused by involuntary, intermittent, and spasmodic contractions of the diaphragm and intercostal muscles. It starts with a sudden inspiration and ends with an abrupt closure of the glottis. Even though a hiccup is thought to develop through the hiccup reflex arc, its exact pathophysiology is still unclear. The etiologies include gastrointestinal disorders, respiratory abnormalities, psychogenic factors, toxic-metabolic disorders, central nervous system dysfunctions and irritation of the vagus and phrenic nerves. Most benign hiccups can be controlled by traditional empirical therapy such as breath holding and swallowing water. However, though rare, a persistent hiccup longer than 48 hours can lead to significant adverse effects including malnutrition, dehydration, insomnia, electrolyte imbalance, and cardiac arrhythmia. An intractable hiccup can sometimes even cause death. We herein describe a patient with non-small cell lung cancer who was severely distressed by a persistent hiccup.

• Journal of Chest Surgery
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• v.24 no.5
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• pp.522-528
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• 1991

A successful repair of aortic dissection of descending thoracic aorta was performed in a 48 year old man. The patient was visited ER because of abruptly onset chest pain. On admission, Chest film showed mediastinal widening and undertaken chest CT, echocardiogram and angiogram There was evidence of dilation on descending aorta with internal separation of intimal calcification. Aneurysmal sac with dissection was noted from just below left subclavian artery to 2cm above of diaphragm. He underwent thoracotomy and the impending ruptured aneurysm of the aorta was replaced with a Woven Dacron graft[20Yo Albumin preclotted] using LA-femoral bypass. Postoperative course was uneventful.

• Journal of Chest Surgery
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• v.23 no.2
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• pp.357-361
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• 1990

The pulmonary sequestration is rare congenital pulmonary disease with nonfunctioning lung tissue supplied by aberrant arteries arising from systemic arteries-thoracic aorta, subclavian artery, innominate artery, internal mammary artery, etc. In our country, only 23 cases were reported previously and the majority was intralobar pulmonary sequestration except 2 cases. The patient was 17 year-old man and admitted due to intermittent cough, productive sputum and fever for 8 years. On simple chest P \ulcornerA view, multiple cysts with air-fluid levels were located at left lower lobe area. Aortogram revealed two aberrant arteries arising from thoracic aorta just above the diaphragm. On the operative field, the arteries were 0.7 and 0.3 cm in diameter. Left lower lobectomy was done with ligation of aberrant arteries. The patient was recovered and discharged uneventfully.