• 한국정밀공학회지
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• 제16권8호
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• pp.46-52
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• 1999

Large valves for steam turbines of fossil power plants are exposed to a severe mechanical and thermal loading resulting from steam with high pressure and high temperature. Valve casings are designed to withstand such a loading. During the operation of a plant, temperatures at inner and outer surface of the casings are measured and steam flow is controlled so that the measured difference is lower than the maximum allowable value determined in the design stage. In this paper, a method is presented to calculate the maximum allowable temperature difference at the inner and outer surface of valve casings for steam turbines of fossil power plants. The finite element method is used to analyze distribution of temperature and stresses of a casing under the operating condition. Low cycle fatigue and creep rupture are taken into consideration to determine the maximum allowable temperature difference. The method can be usefully applied in the design stage of the large valves for the steam turbines, contributing to safe and reliable operation of the fossil power plants.

• Journal of Chest Surgery
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• 제22권6호
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• pp.1036-1043
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• 1989

Seventy eight patients underwent operation for combined multiple valve disease, with an overall early mortality of 14.1 % from January, 1983 to September, 1988 in the department of thoracic and cardiovascular surgery of Pusan National University Hospital. All of the above cases had combined multiple valve procedures. There were 33 mitral valve replacements and tricuspid annuloplasties, 33 aortic and mitral valve replacements, 5 aortic and mitral valve replacements with tricuspid annuloplasties, 3 aortic valve replacements and mitral annuloplasties, 1 open mitral commissurotomy and tricuspid annuloplasty and, 1 mitral valve replacement and primary closure of tricuspid valve cleft, 1 mitral valve replacement and aortic commissurotomy, 1 mitral, aortic and tricuspid valve replacement were done. 44 were male and 34 were female and the age distribution was from 14 to 57 with mean 38 year old. According to NYHA[New York Heart Association] classification, 49 patients were class I, 19 patients were class Il and 10 were class IV. Average perfusion time was 205.3 minutes. The live patients perfusion time was 178.7 minutes while that of dead ones was 272.0 minutes. Early deaths within 30 days from operation were 11 cases, 6 of which were due to low cardiac output, 3 were acute renal failure and 2 were cardiac rupture. The 65 patients were followed up from 2 to 30 months for a total 20.6 patient years. 1 patient committed suicide because of postoperative depression 1 year after operation. All of the survivors were enjoying their daily life and their NYHA class was superior to the preoperative ones.

• 대한두경부종양학회지
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• 제33권1호
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• pp.53-56
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• 2017

Pharyngocutaneous fistula is one of the most common wound complications after total laryngectomy. The leakage of saliva may cause an erosion of greater vessels nearby and result in a life-threatening bleeding. 65-year-old male received laryngectomy and pharyngectomy followed by Latissimus dorsi flap reconstruction due to recurred laryngeal cancer with oropharyngeal extension after postoperative radiotherapy. Pharyngeal fistula was developed and an excessive fresh blood flowed through the oral and nasal cavity. The patient was transferred to the operating room immediately, and the causing artery was ligated. The rupture of the common carotid artery and its branches should be warned when the pharyngocutaneous fistula is developed. Prompt and proper therapy must be performed for the patients with impending or acute hemorrhage.

• 비교문화연구
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• 제29권
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• pp.133-152
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• 2012

Franciso Ayala's narrative work was published in the collection "Nova novorum" (1926-1929) of Revista de Occidente, founded by $Jos{\acute{e}}$ Ortega y Gasset. The author of Cazador en el alba was well aware of the avant-garde aesthetics and hence he put into practice an artistic rupture of the traditional narrative forms of Realism. The work consists of two short stories: "Cazador en el alba" and "Erika ante el invierno". The use of metaphor, Francisco Ayala's preferred literary device (which Ortega y Gasset already emphasized in The Dehumanization of Art), reveals the influence of $Ram{\acute{o}}n$ $G{\acute{o}}mez$ de la Serna's Aphorisms. Through a metaphoric language, "Cazador en el alba" describes the life of Antonio, a soldier and peasant, who visits Madrid and confronts the urban reality of the metropolis. "Erika ante el invierno" portrays with a singular depth the solitude of a woman living in another metropolis, Berlin. The author confessed that he wrote both short stories influenced by the European avant-garde and its use of poetic imagery and metaphor, common practice at that time. However, the main purpose of this article is to reflect upon the society of the first decades of the $20^{th}$ Century: the city, the people and their lives, the societal changes, as well as the innovative perspective of the new art.

• 한국주조공학회지
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• 제42권6호
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• pp.392-397
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• 2022

In order to compliant the stringent exhaust emission regulations, higher fuel efficiency and cleaner exhaust gas in combustion engines have been required. To improve combustion efficiency, an exhaust gas temperature is increasing, therefore higher temperature resistance is required for components in exhaust system, especially turbine wheel in turbocharger. IN100 looks quite attractive candidate as it has high temperature properties with low density, however it has low castability due to poor ductility at high temperature. In this study, the balance of Al and Ti composition was optimized from the base alloy IN100 to improve the high temperature ductility by expanding the γ single phase region below the solidification temperature, while obtaining the high temperature strength by maintaining the volume fraction of γ' phase equivalent to IN100 around 1000℃. Furthermore, the high temperature creep rupture life increased by adding a small amount of Ta. The alloy developed in this study has high castability, low density and high specific strength at high temperature.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제26권5호
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• pp.284-289
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• 2023

A 14-year-old girl was admitted to the emergency department for excessive bile-containing vomiting and severe abdominal pain. She had been healthy until she intentionally lost 25 kg over a 6-month period. Thick, bloody bile-mixed food particles were drained from the stomach through a nasogastric tube. Abdominal computed tomography revealed huge stomach dilatation with extensive gastric pneumatosis, possible near rupture, acute pancreatitis, and a very narrow third of the duodenum, indicating superior mesenteric syndrome. Gastrofibroscopy revealed multiple hemorrhagic ulcers and numerous beadlike cystic lesions in the stomach. Laboratory examination results were notable for severe deficiencies in critical nutrients, including iron, zinc, proteins, and prealbumin, as well as undernutrition-associated endocrine complications such as hypothyroidism and hypogonadotropic hypogonadism. Excessive vomiting ceased after the endoscopic removal of stagnant gastric contents. Gastric pneumatosis improved after 3 days of supportive care.

• Korean Journal of Radiology
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• 제23권8호
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• pp.785-793
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• 2022

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease involving apocrine-bearing sites. It is characterized by recurrent painful nodules and abscesses that potentially rupture, resulting in sinus tract formation, fistulas, and scarring. HS tends to be found in the intertriginous areas (i.e., the axillary, inguinal, and perianal areas of the body). HS may be uncommon for radiologists because its diagnosis is usually based on clinical assessment. However, diagnosis based solely on clinical manifestations can underestimate the severity of HS. Ultrasonography and MRI play a critical adjunct role in determining the severity and extent of the disease and greatly aid its management. Given that MRI is an effective imaging tool, its role in the analysis of severe and anogenital HS lesions merits considerable attention. Unfortunately, anoperineal HS imposes diagnostic dilemmas. It has multiple symptoms and presentations and often mimics other diseases in the intertriginous areas. Therefore, a thorough understanding of HS is essential to avoid delayed diagnoses. This review highlights the typical MRI imaging features and staging of HS, emphasizing on the anoperineal location. The review also differentiates the disease from mimics to facilitate the prompt delivery of appropriate treatment and improve patients' quality of life.

• Journal of Trauma and Injury
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• 제19권2호
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• pp.201-205
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• 2006

Tension viscerothorax (gastrothorax) is rare life-threatening disease which is caused by air trapped in viscera. A distended viscera in the hemi-thorax shifts the mediastinal structures and causes extra-cardiac obstructive shock. A defective diaphragm is caused by abdominal trauma or a congenital anomaly. Traumatic diaphragmatic injury can be missed until herniation develops several years after blunt trauma. In our case, a 10-year old boy developed hemodynamic compromise in the emergency department. Three years earlier, he had suffered blunt abdominal trauma during a pedestrian traffic accident, but there was no evidence of diaphragmatic injury at that time. He was successfully resuscitated by gastric decompression and an emergent thoracic operation. The operation finding revealed a traumatic diaphragmatic injury. Tension viscerothorax is a rare, but catastrophic, condition, so we suggest that addition of tension viscerothorax to the Advanced Trauma and Life Support (ATLS) guidelines may be helpful.

• 대한기계학회논문집A
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• 제34권4호
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• pp.457-465
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• 2010

본 연구에서는 McVetty 와 Monkman-Grant 의 모델에 기초하여 만들어진 새로운 크리프 수명예측 모델인 Taylor 급수(T-S) 모델을 제안하였다. 본 모델은 회귀분석에서 발생하는 오차를 줄이기 위하여 McVetty 모델에서 sinh 함수를 Taylor 급수에 의해 변환한 후 첫 3 개항을 취한 것으로서 모델중의 상수 값은 통계학적 방법인 최대가능성 기법을 이용하여 결정되었다. T-S 모델을 이용하여 Alloy 617 의 크리프 수명을 예측한 결과 Eno, 지수함수 및 Larson-Miller(L-M) 방법에 비해 더 정확한 예측을 하는 것으로 나타났다. 또한 T-S 모델은 특정 온도에서 크리프 수명 예측을 할 수 있는 등온 T-S(IT-S) 모델로 표현될 수 있었으며, IT-S 모델은 Alloy 617 의 장시간 크리프 수명예측에서 가장 좋은 예측을 하는 것으로 나타났다.

• Archives of Plastic Surgery
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• 제34권3호
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• pp.358-364
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• 2007

Purpose: A life-threatening hemorrhage resulting from a severe facial fracture is rare, but it needs a prompt and aggressive treatment. Especially, a massive oronasal bleeding combined with midfacial fracture which may result from the rupture of the internal maxillary artery. With the recent advances in the radiologic intervention, its use has increased for managing these life threatening case. We reviewed its usefulness with our experiences and literatures. Methods: A retrospective review was performed to determine the usefulness of the transcatheter arterial embolization in patients with panfacial trauma. If the vital signs were unstable, cardiopulmonary resuscitation was performed. Oronasal bleeding was controlled with nasal packing and electrocautery. All injured regions were studied by radiologic study including CT. Even after primary management, if the oronasal bleeding was persistent, radiologic intervention was performed 10 patients were treated with transcatheter arterial embolization and the bleeding focus controlled by embolization with polyvinyl alcohol and gelfoam. Results: After the intervention, the vital signs became stable and there were no complications from embolization in the follow-up for 6 months. Also patients could recover through appropriate operations. Conclusion: Transcatheter arterial embolization for maxillofacial injury has many advantages for both, the doctor and the patient. First, less pain is induced than a compression device or an operation, which is another way to treat oronasal bleeding. Second, it does not need general anesthesia. And through a single procedure not only we can know the accurate bleeding point, but we can also bleeding by embolization.