• Proceedings of the KOR-BRONCHOESO Conference
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• 2007.10a
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• pp.48-48
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• 2007

• 대한핵의학회:학술대회논문집
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• 1986.05a
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• pp.121.1-121.1
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• 1986

• 대한생식의학회:학술대회논문집
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• 2003.12a
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• pp.88-89
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• 2003

• Journal of the Korea Concrete Institute
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• v.26 no.1
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• pp.87-95
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• 2014

Experimental investigation on the structural behavior of steel fiber-reinforced ultra high performance concrete (UHPC) beams subjected to torsion are presented. Six tests carried out on square beams under torsional moment are presented. The experimental parameters were the volume fraction of the fibers and closed-stirrup ratio. The volume fraction of the fibers was 1.0% and 2.0%. The closed-stirrup ratio was 0, 0.35%, and 0.70%. The test results indicated that ultimate torsional strength increased with increasing fiber volume, and that ultimate torsional strength also increased with increasing the closed-stirrup ratio. In addition, predictive equations for evaluating the ultimate torsional strength of UHPC beams were proposed. The comparison between computed values and the experimentally observed values was shown to validate the proposed analytical equations. It was found that predictions by using proposed equation provides good agreement with test results of UHPC beams.

• Journal of Bio-Environment Control
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• v.14 no.3
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• pp.218-231
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• 2005

This paper reviews the engineering approach needed to support humans during their long-term missions in space. This approach includes closed plant production systems under microgravity or low pressure, mass recycling, air revitalization, water purification, waste management, elimination of trace contaminants, lighting, and nutrient delivery systems in controlled ecological life support system (CELSS). Requirements of crops f3r space use are high production, edibility, digestibility, many culinary uses, capability of automation, short stems, and high transpiration. Low pressure on Mars is considered to be a major obstacle for the design of greenhouses fer crop production. However interest in Mars inflatable greenhouse applicable to planetary surface has increased. Structure, internal pressure, material, method of lighting, and shielding are principal design parameters for the inflatable greenhouse. The inflatable greenhouse operating at low pressure can reduce the structural mass and atmosphere leakage rate. Plants growing at reduced pressure show an increasing transpiration rates and a high water loss. Vapor pressure increases as moisture is added to the air through transpiration or evaporation from leaks in the hydroponic system. Fluctuations in vapor pressure will significantly influence total pressure in a closed system. Thus hydroponic systems should be as tight as possible to reduce the quantity of water that evaporates from leaks. And the environmental control system to maintain high relative humidity at low pressure should be developed. The essence of technologies associated with CELSS can support human lift even at extremely harsh conditions such as in deserts, polar regions, and under the ocean on Earth as well as in space.

• Journal of Chest Surgery
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• v.34 no.9
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• pp.720-723
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• 2001

A case of Marfan’s syndrome with atresia of right coronary artery is reported. A 45-year-old woman, who was diagnosed as Marfan’s syndrome 1 year ago, came to the hospital complaining of acute chest pain. The patient showed arachynodactyly, pectus carinatum, and long and slender extremities. In echocardiography there were severe aortic regurgitation measured grade IV and aortic dilatation of ascending aorta maximally 5.9 cm in diameter. Mitral regurgitation was mild, but there were also moderate left ventricular dilation and moderately decreased ejection fraction of left ventricle. At operation, atresia of right coronary artery was found. We performed Bentall type operation with SJM 27mm valved conduit for left coronary artery, and Piehler’s modification for right coronary artery bypass using 6mm PTFE graft. The atretic portion of right coronary artery from the suspected right coronary ostium to distal coronary flow was about 4 cm in length. The combination of right coronary artery atresia and Marfan’s syndrome is very rare. The author describes the rare case, which is treated with combined technique of Bentall and Piehler modification for reconstruction of coronary circulation.

• Journal of Yeungnam Medical Science
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• v.7 no.2
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• pp.39-48
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• 1990

Congenital duodenal obstruction in the newborn infant may be due to a variety of causes. Duodenal obstruction often presents with bilious vomiting and upper abdominal distention. Diagnosis is usually established on plain x-ray of the abdomen by the classic finding of the double-bubble. In the period July 1986 to June 1990, 16 patients with congenital duodenal obstruction were operated and the following results were obtained. 1. Sixteen patients were comprised of 11 males and 5 females, the ratio of male and female was 2.2:1. 2. Thirteen patients(81%) had been admitted to our hospital during one month of life. 3. Congenital duodenal obstruction was in 16 cases; malrotation in eight(50%), annular pancreas in six(38%), type 1 atresia in one(6%), and wind-sock anomaly in one(6%). 4. There were two premature patients and six patients of small for gestational age. 5. Overall, bilious vomiting, occurring in three fourths, was the single most frequent presenting complaint. 6. Polyhydramnios occurred in two of the patients. 7. Diagnosis was possible with clinical symptom and simple abdomen. 8. The operative procedures performed were ; duodenoduodenostomy in five, duodenojejunostomy in two, excision of wind-sock membrane in one, and Ladd's procedure in eight. 9. A total of ten asociated congenital anomalies were found in six patients. 10. Postoperative complications occurred in five cases(31%).

• Journal of Chest Surgery
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• v.41 no.5
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• pp.671-674
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• 2008

Jejunum and fasciocutaneous and myocutaneous flaps are theoretically recommended as esophageal substitutes in reconstruction of the esophagus after several occurrences of failed reconstruction. However, other esophageal substitutes should also be considered. Secondary esophageal reconstruction was successfully performed on a 24-year-old woman who had a history of cervical, thoracic, and abdominal operations and esophageal stricture secondary to several failed reconstructions for esophageal atresia and tracheo-esophageal fistula 21 years prior. The esophageal reconstruction was done subcutaneously by end-to-side anastomosis at the left cervical area using a deformed stomach graft. The patient was discharged with the ability to consume a regular diet after the operation.

• Journal of Chest Surgery
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• v.31 no.1
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• pp.46-51
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• 1998

Treatment of esophageal perforation when diagnosed late remains controversial. Ten consecutive patients since 1990 were treated late(later than 24 hours) for esophageal perforation with primary repair. Four perforations were iatrogenic, 3 were spontaneous, 2 were foreign body aspiraton and 1 was trauma. The interval from perforation to operation was 116 hours in mean and 48 hours in median value. The principles of repair included (1) a local esophagomyotomy proximal and distal to the tear to expose the mucosal defect and intact mucosa beyond, (2) debridement of the mucosal defect and closure, (3) reapproximation of the muscle, and (4) adequate drainage. The repair was buttressed with parietal pleura or pericardial fat in 9 patients. Associated distal obstruction was treated with dilation and esophagomyotomy intraoperatively. There was one mortality and cause of death was massive gastric bleeding due to gastric ulcer on 33rd day after operation. Five patients had leak at the site of repair and these cases were treated completely with conservative treatment except a mortality case. In conclusion, in the absence of malignant or irreversible distal obstruction, meticulous repair of perforated esophagus and adequate drainage are preferred approach, regardless of the duration from the injury to the operation.

• Journal of Chest Surgery
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• v.35 no.7
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• pp.542-547
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• 2002

Background: Postpneumonectomy empyema(PPE) is an infrequent but potentially life-threatening complication. To date, various surgical efforts have been made to manage this complication. We reviewed our 20-year surgical experience of PPE and long-term follow-up data. Material and Method: Total of 37 patients who were treated for PPE between fan, 1980 and Jun, 2000 were included. Various clinical factors such as micro-organism, operative method and timing, presence of bronchopleural fistula(BPF), underlying disease and fate of empyema cavity were retrospectively reviewed and analyzed. Result: Majority of patients(34) underwent Eloesser operation for effective drainage. There was only one operative mortality. The causative organisms were Staphylococcus species and Pseudomonas species in 46% BPF was found in 20 cases, among which spontaneous closures took place in 4 cases. The chest wall was closed in 40%(8/20) of patients with BPF, compared to 59%(10/17) without BPF. The closure rate was statistically better in patients without BPF(p=0.006). Even though the patients with benign disease showed higher closure rate(50%) than those with lung cancer (31%), the difference was not significant(p=0.25). Conclusion: Eloesser procedure was an effective method for initial drainage of PPE cavity with low operative mortality. Given the findings of low spontaneous closure rate of BPF, aggressive approach to close the BPF is mandatory to achieve the final goal of chest wall closure. It was found that majority of patients still left their chest cavity opened, even after controlling the active inflammation of the empyema cavity. More aggnessive approach for chest wall closure is recommended in all patents with benign disease and in selective patients with lung cancer if there is no evidence of recurrence at several years after the initial operation.