• Journal of Chest Surgery
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• v.56 no.3
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• pp.204-205
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• 2023

• Journal of Chest Surgery
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• v.10 no.1
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• pp.156-163
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• 1977

This is a report of a case in which mitral valve replacement was performed using Starr-Edwards ball valve [model 6230] by total cardiopulmonary bypass with total hemodilution prime and moderate hypothermia. The patient was 21 year old girl, and mitral valvular symptoms occurred 5 years ago. According to clinical features of the disease, the patient was classified as the class IV of N.Y.H. A. cla3sification. The preoperative diagnosis of mitral insufficiency was made mainly by left ventriculography of roentgenologic study. The mitral valve was highly deformed due to scar contraction of valve leaflets and shortening of chordae tendineae. After prosthetic valve replacement, no abnormal hemodynamic signs were observed. The postoperative course was uneventful.

• Journal of Chest Surgery
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• v.41 no.2
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• pp.260-263
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• 2008

We performed three cases of extraanatomic bypass graft for treating adult coarctation. Two cases of left subclavian artery to descending aorta bypass graft were done via left thoracotomy for treating 2 patients who had extensive aortic occlusive disease. One case of ascending aorta to descending aorta bypass graft and aortic valve replacement was done via median sternotomy for a patient who had combined arch hypoplasia and aortic valve regurgitation. One patient was reoperated on for aneurysm rupture of an anastomosis site four months after the first operation and two patients have had no specific problems during and after their operations.

• Journal of Chest Surgery
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• v.23 no.3
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• pp.482-487
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• 1990

The leading cause of death in patients with chronic renal failure is cardiovascular diseases. The problems relevant to cardiac surgery in these patients are occurring more frequently with a growing number of patients at risk. Among these, important risk factors related to uremic patients undergone open heart surgery are fluid and electrolytes imbalance, coagulopathy, increased susceptibility to infection. Since 1968 when Lansing and colleagues reported the first successful aortic valve replacement in patients with chronic renal failure and infective endocarditis, there have been increasing reports of the cardiopulmonary bypass surgery in chronic renal failure patients with acceptable perioperative morbidity and mortality From Jan. 1988 to Nov. 1989 we have experienced four uremic patients necessitating open heart surgery ; one needing a coronary artery bypass graft and the other 3 needed cardiac valve replacement. Based on our observations we would like to suggest followings 1]Intraoperative ultrahemofiltration during C-P bypass thought to be an excellent means for the control of hyperkalemia and fluid balance. 2] The immediate postoperative application of peritoneal dialysis instead of hemodialysis is beneficial in controlling fluid and electrolyte imbalance. 3]The cause of one early postoperative death was not associated to renal failure, rather it was the result of an accidental rupture in the right ventricular wall.

• Journal of Chest Surgery
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• v.20 no.3
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• pp.557-564
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• 1987

From September 1980 to July 1986, 135 cases of cardiac valve surgery were performed under the cardiopulmonary bypass. Out of 135 cases, single valve surgery was 114 cases including open mitral commissurotomy 17, mitral annuloplasty 2, mitral valve replacement 85, and aortic valve replacement 10 and double valve surgery was 21 cases. There were 68 males and 67 females ranging from 9 to 57 years of age. Early death within 30 days after operation was 17 cases [12.6%] and caused of death were ventricular arrhythmia 5, low cardiac output syndrome 4, excessive bleeding 3, pulmonary complication 2, and so on. Among 118 early survivors, 5 cases [5.1%] of late death were developed over a period of 2 to 72 months, and main cause of death was fatal bleeding complication associated with anticoagulation therapy. Symptomatically, 91.8% of patients were in NYHA functional class I or II at the end of the follow-up.

• Journal of Chest Surgery
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• v.4 no.1
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• pp.51-54
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• 1971

37 years old female was admitted with chief complaints of dyspnea on exertion and hemoptysis. Past history and family history were non-contributory. Physical examination showed Grade III systolic murmur at the apex, which transmitted to the back. E. K. G. and X-ray findings were compatible with the mitral insufficiency. With small size of Beall mitral valve, mitral valve replacement was done under the cardia-pulmonary bypass using hemodilution technic. Patient was tracheotomized after operation and assisted respiration was done for four weeks. Postoperatively, all signs were fine and patient walked around the ward without any difficulty, but she was in psychotic state. On postoperative 60th day, she complained of sudden dyspnea and on chest film, tracheal stenosis was found and recannulation of the tracheal tube was made. Thereafter, she was quite fine until postoperative 110th day when she, by berself, removed the tracheal cannula and died of asphyxia. Autopsy findings of the valve showed no thrombosis, no variance of the valve, and good endothelization of the valve cuffs. Asphyxia, due to removal of the tracheal connula by herself under psychotic state, was considered to be the cause of death in this patient who had tracheal stenosis after tracheostomy.

• Journal of Chest Surgery
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• v.28 no.2
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• pp.188-192
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• 1995

A 50 year old man with acute aortic dissection DeBakey type I, involving right coronary artery and aortic valve, underwent replacement of the ascending aorta and aorto-right coronary bypass grafting. The operative findings showed a large transverse intimal tear was at about 4cm above the aortic valve. The dissection extended out into the proximal right coronary artery. And we found that the right coronary artery originated from the left sinus of Valsalva, run transversally in the aortic wall, with partial rupture. Postoperatively he had no ischemic cardiac symptoms and neurologic complications. He was discharged on postoperative 9th day with good result.

• Journal of Mechanical Science and Technology
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• v.19 no.12
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• pp.2321-2329
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• 2005

One means of fulfilling $CO_2$ emission legislation is to downsize engines by boosting their power using turbochargers or mechanical superchargers. This reduces fuel consumption by decreasing the engine displacement. When a turbocharger, which is preferable to a mechanical supercharger in terms of fuel efficiency, is used, there is insufficient availability of exhaust gas energy at low engine speeds, resulting in an unfavorable engine response. Therefore, mechanically driven superchargers have increased in popularity due to their quick response to changing speeds in the transient phase. However, since a mechanical supercharger obtains its driving power from the engine, it is difficult to decrease its fuel consumption. This remains a large negative factor for superchargers, despite their excellent dynamic performance. This study aims to develop a power control concept to improve the fuel economy of a mechanical screw supercharger, which could then be used for engine downsizing.

• Journal of Chest Surgery
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• v.51 no.6
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• pp.399-402
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• 2018

A 61-year-old woman who presented with claudication and dyspnea on exertion was found to have severe calcified narrowing of the descending aorta and severe insufficiency of the aortic valve. These findings were compatible with Takayasu arteritis. To treat these hemodynamic abnormalities, extra-aortic bypass surgery combined with replacement of the aortic valve and ascending aorta-to-hemiarch replacement was performed through a separated upper hemi-sternotomy and limited median laparotomy. We present our successful surgical experience with this case.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.7
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• pp.1003-1011
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• 2009

This study aims at precise control of oil outlet temperature in the oil cooler system of machine tools for enhancement of working speed and processing accuracy. PID control logic is adopted to obtain desired oil outlet temperature of the oil cooler system with hot-gas bypass method. We showed that the gains of PID controller could be easily determined by using gain tuning methods to get the gain of PID controller without any mathematical model. We also investigated various gain tuning methods to design the gains of PID and compared each control performance for selecting the optimal tuning method on the hot gas bypass method through experiments. Moreover, we confirmed excellent control performance with proposed PI controller gain even though disturbances were abruptly added to the experimental system.