• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.1
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• pp.11-21
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• 1998

During an earthquake, there are three main components of excitation : horizontal excitation of the ground, vertical excitation of the pile due to superstructure feedback produced by vertical excitation of the ground, and the seawater excitation induced by the vertical ground shaking, that is, "the seaquake." These excitations could have effects on the soil plugs in open-ended pie piles installed at offshore sites. In this study, seaquake excitation induced by the vertical ground shaking was simulated by pulsing the water pressure at the seabed. During a seaquake, due to the induced excess porewater pressure and pressure gradients in the soil, the capacity of open-ended pipe piles installed in a simulated sea depth of greate than 220 m was reduced serevely and the soil plugging resistance was degraded by more than 80% The soil plug was failed because of eh upward seepage forces that developed in the soil plug due to excess pore water pressure produced in the bottom of the soil plug during the seaquake, The compressive capacity of ar open-ended pile in a simulated sea depth of less than 220 m was reduced only by about 10% and the soil plug resistance was degraded by less than 5%.s than 5%.

• Proceedings of the KOR-BRONCHOESO Conference
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• 2003.09a
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• pp.113-113
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• 2003

성문과 성문하부의 기도 폐쇄는 위치 정도 원인 기간 등은 환자에 따라 다르고 그 치료방법 역시 다양하다. 주 원인으로는 기관내 삽관, 각종 외상 및 화상 등 을 들 수 있다. 이러한 질환의 치료 목적은, 기관내 튜브나 기관 캐뉼러 를 통하지 않고 비강을 통하여 자연스럽게 호흡할 수 있도록 기도를 유지 하면서 발성이 가능하고 기고 흡인 없이 연하가 가능하도록 하며 기침 반사가 원활하게 되도록 하는데 있다. 치료목적의 달성을 위하여 협착의 경우, 단계 즉 초기 단계 또는 성숙단계 여부, 위치, 정도, 범위 환자의 연령 전신상태 등을 술전에 잘 평가하고 수술도중의 소견과 술자의 경험이나 기호에 따라 적절한 치료법을 선택하여 치료해야 한다. 후두 외상에 의한 기도 문제는 다른 외상에 비해 흔하지 않은데 이는 연골의 유연성과 후두의 가동성 그리고 후두가 하악과 흉골사이에 위치하여 외상시 보호받게 되는 해부학적 특성에 기인한다. 여러 요인으로 인하여 진단이 늦어질 수도 있는데 이러한 경우 심각한 증상이 초래 되거나 치료가 의 시기가 지나 후두 또는 기관 협착, 발성장애등의 후유증이 유발 될 수 있다.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1991.06a
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• pp.25-25
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• 1991

최근 교통사고의 증가, 심폐술의 보편화 및 보조호흡을 필요로 하는 환자의 증가에 따라 경구적 혹은 기관절개술을 통해 기관내 삽관을 장기간 유치하는 경우가 많아져서 이에 따른 합병증으로 기관협착증의 빈도가 높아지게 되었다. 기관내 삽관후 기관협착증을 초래하는데에는 관의 외경, 삽관시 외상, 삽관유치기간, 기계적 보조호흡시 관의 이동, cuff 의 압력 등의 요인이 작용한다. 이러한 요인에 의해 기관내 삽관을 장기간 유치시 기관점막에 대한 지속적인 압박으로 점막하부의 압박괴사 및 혈관의 폐쇄로 인해 기관연골의 무혈성 괴사를 초래하여 환상의 기관협착이 병발하게 된다. 기관협착증에 대한 치료방법으로서는 여러 가지가 있으나 환상의 기관협착증인 경우는 협착부위의 절제 및 단단문합술을 시행하고 절제부위가 광범위한 경우는 release technique 을 이용하여 문합부위의 장력을 줄여주는 것이 효과적인 치료방법으로 알려져 있다. 저자들은 최근 기관내 삽관후에 병발한 환상기관협착증 3례(다발성 골절 1례, 기관지 천식 1례, 약물중독 1례)에 대해 기관절제 및 단단문합술을 경험하였기에 보고하고자 한다.

• Journal of Chest Surgery
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• v.36 no.6
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• pp.444-447
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• 2003

Sleeve pneumonectomy can be a method of treatment in a selected patient with bronchogenic carcinoma involving carina. A 64 years old male with a history of mitral valve replacement via midsternotomy 13 years ago and resection of papilloma of the vocal cord 2 years ago. The patient was admitted due to blood-tinged sputum. Bronchoscopy and computerized tomogram of the chest revealed 3.5 cm mass at lower margin of the trachea and totally obstructing the left main bronchus. A biopsy revealed squamous cell carcinoma. He underwent left sleeve pneumonectomy through sequential bilateral thoracotomy without cardiopulmonary bypass, and the pathologic stage was T4N0M0 stage IIIB. The patient is being followed through the outpatient clinic in good general condition.

• Journal of Chest Surgery
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• v.36 no.5
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• pp.363-366
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• 2003

Background: Left ventricular rupture after acute myocardial infarction is a serious complication with high mortality. Emergency operation is usually the only available treatment. A 76-year-old female with persistent chest pain and syncopal attacks was admitted. Transthoracic echocardiography showed the pericardial effusion and generalized hypokinesia of the inferolateral wall of left ventricle. Coronary angiography revealed a total occlusion of the first diagonal branch. After percutaneous transluminal coronary angioplasty with coronary stent and insertion of intraaortic balloon pump, emergency operation was performed. Under cardiopulmonary bypass and cardiac arrest with cold blood cardioplegia, coronary artery bypass graft with saphenous vein, pericardial patch covering on the rupture area with 6-0 polypropylene running sutures, and fibrin glue compression under the patch were performed. We present a case of left ventricular (free wall) rupture after acute myocardial infarction.

• Tuberculosis and Respiratory Diseases
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• v.40 no.6
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• pp.714-718
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• 1993

Tracheobronchopathia osteoplastica(TPO) is a rare disorder characterized by submucosal cartilaginous or bony projections into the tracheobronchial lumen with sparing of the posterior membranous portion of tracheobronchial tree. The etiology of TPO is still unknown. A 44-year-old male was admitted to Seoul Paik Hospital Inje University due to left chest pain for 10 days. On the past history he had sufferred from symptoms of bronchitis for several months. He showed radiologically massive pleural effusion in left lung field. Pleural biopsy revealed chronic pleuritis with hemorrhage. Bronchoscopic findings showed multiple intraluminal portruding nodule from just below the vocal cord to carina and both main bronchi. Pathology of bronchoscopic biopsy showed abnormal proliferation of atypical bony and carilagious nodules in the tracheal submucosa. We experianced a case of tracheobronchopathia osteoplastica involving the trachea and main bronchus in 44-year old male, associated with massive pleural effusion. This report is a case of TPO with review of literature.

• Korean Journal of Environment and Ecology
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• v.35 no.1
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• pp.48-67
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• 2021

Plant species exhibit current characteristics as a result of interactions with environmental conditions. The plants of Viola sp. have selected chasmogamous flowers with vigorous vegetative propagation or development of cleistogamous flowers as an adaptation strategy. Viola websteri is distributed on the Korean peninsula and the eastern part of Jilin Province, China. The center and edge of the distribution are expected to exhibit different population-dynamics. It is necessary to investigate the cause of its current limited distribution even though V. websteri has a mixed-mating strategy. Firstly, We examined the vegetation environment of habitats and evaluated its characteristics. Growth characteristics were examined through plant phenology. We then evaluated the population structure, characteristics of chasmogamous flowers, and productivity of cleistogamous flowers. Moreover, we compared population sizes between 2014 and 2018. Most habitats were located in deciduous broadleaf mixed forests adjacent to valleys. V. websteri produced chasmogamous flowers with self-incompatibility in April-May and cleistogamous flowers in June-September. The cleistogamous flower production is a strategy ensuring seed production under uncertain environmental fluctuations; these were approximately twice as numerous as chasmogamous flowers. The population structure was distinguished into stable and very unstable regions. There were sites where the population experienced a sharp decline in the 2018 compared to that of 2014. This large decline was found in the edge populations. The habitats had different microsites depending on the natural disturbances of drought and the matrix constituting the habitat, thus supporting various plants. Ensuring the production of seeds through cleistogamous flowers, it was determined that rapid seedling re-establishment and population replenishment were possible when the natural disturbance factor was removed. Environmental factors did not equally affect all populations or individuals. Therefore, it was expected that it would be able to persisted in a long time, despite the rapid decrease in the number of individuals in the population regionally. Local extinction and re-establishment are likely to repeat according to environmental change. We propose the additional population investigation based on this works are required. We also suggest a need to assess the long-term population dynamics and the genetic characteristics of chasmogamous flowers and cleistogamous flowers to establish and implement effective conservation strategies.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.4
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• pp.377-385
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• 2013

To identify the effects of an outflow area on pool boiling heat transfer in a vertical annulus, three different flow restrictors were studied experimentally. For the test, a heated tube of smooth stainless steel and water at atmospheric pressure were used. Both annuli with open and closed bottoms were considered. To validate the effects of the outflow area on the heat transfer, the results of the annulus with the restrictor were compared with the data for the plain annulus without the restrictor. The reduction of the outflow area ultimately results in a decrease in the heat transfer. As the outflow area is very small, a slight increase in heat transfer is also observed. The major cause of this tendency is explained as the difference in the intensity of liquid agitation cause by the movement of coalesced bubbles. It is identified that the convective flow, pulsating flow, and evaporative mechanism are considered as the important mechanisms.

• Journal of Chest Surgery
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• v.31 no.7
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• pp.725-729
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• 1998

Endobronchial leiomyoma is extremely rare and accounts for less than 2% of benign tumors of the lower respiratory tract. Leiomyomas are predominantly found in the young and the middle aged : of the average age being 35 years for bronchial and lung parenchymal lesions and 40.6 years for tracheal lesions. The symptom depends on the location of the tumor, its size, and changes in the lung distal to the lesion. A 37-year-old woman was admitted to our hospital complaining of coughing. Bronchoscopy revealed complete obstruction of the right main bonchus at the carina by an oval-shaped, nonulcerative, smooth, and pinkish-tan tumor with a broad margin and extended to the left main bronchus. A biopsy was performed and showed a benign spindle cell tumor. A right pneumonectomy was performed because of chronic infection, and the lung could not expanded during aeration. The histological diagnosis of the resected specimen was leiomyoma. The postoperative course was uneventful.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.404-407
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• 1999

Spontanous hematoma of the esophagus is a rare condition affecting middle aged or elderly women. We experienced one case of esophageal hematoma which attracted our attention due to its confusing presentation clinically. The pathogenesis has been in dispute so far. The diagnosis has traditionally been made by barium esophagogram. We proved the diagnosis of spontaneous hematoma of the esophagus by utilizing CT scan and MRI. This condition led to conservative treatment and full recovery ultimately, but we performed the surgical correction because the filling defect persisted and the dysphagia got worse on the 20th day of hospital stay. Hematoma was located between the inner layer of circular muscle and the outer layer of longitudinal muscle which we considered as intermuscular hematoma of the esophagus.