• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.5
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• pp.74-80
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• 2012

Past few years have seen the growing importance of micro shock tubes in various engineering applications like micro combution, micro propulsion, particle delivery systems. But in order to efficiently apply Micro Shock Tube to such areas require the detailed knowledge of shock characteristics and flow field inside a micro shock tube. Due to many factors such as boundary layer, low Reynolds number and high Knudsen number shock propagation inside micro shock tubes will be quite different from that of the well established macro shock tubes. In the present study, experimental studies were carried out on micro shock tubes of two diameters to investigate flow characteristics and shock propagation. Pressure values were measured at different locations inside the driven section. From the experimental values other parameters like shock velocity, shock strength were found and shock wave diagram was constructed.

• Journal of Chest Surgery
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• v.31 no.6
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• pp.604-609
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• 1998

Trauma to the thorax represents a significant portion of injuries seen in an inner-city emergency room. Although most of these patients may be sucessfully managed without thoracotomy, a certain percentage requires operative intervention either immediately or within several hours. 126 records of patients who had early thoracotomy for chest trauma from March 1986, to June 1997, in the Department of Thoracic and Cardiovascular Surgery in Masan Samsung General Hospital were reviewed. There were 96 males and 30 females whose ages ranged from 4 to 72 years, with a mean age of 32.8 years. The modes of injury were as follows : stab wounds, 55 cases(44%), blunt trauma, 70 cases(55%), and gunshot wound, 1 case(1%). Immediate operation was performed in 105 cases(84%) and delayed operation in 21 cases(16%). Indications that operation was necessary were hemorraging and shock in 66 cases(52%), cardiac tamponade in 27 cases(21%), and rupture of the diaphragm in 33 cases(27%). Most of these patients were sucessfully treated but 21 cases were resulted in death. The mortality rate was 16.6% and common causes of death were irreversible shock and hypoxia.

• Journal of Chest Surgery
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• v.30 no.7
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• pp.724-728
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• 1997

We experienced a case of thoracic aortic aneurysm combined with coronary artery disease. A 68-year-old man complained of anginal pain in the left anterior chest and nonspecific pain in the posterior chest. The aneurysm was extending from left subclavian artery to the diaphragm and sign of impending rupture was noted in the chest CT. Coronary angiograms r vealed significant obstruction of left circumflex coronary artery(>95%) and left anterior descending artery(>50%). Exposure was obtained through the left posterolateral thoracotomy incision in the 4th intercostal space and then partial femoro-femoral cardiopulmonary bypass was established. After aortic cross clamping, the aneurysmal sac was opened and repaired with interposition of 26 mm Hemashield graft. Under the beating heart with femoro-femoral cardiopulmonary bypass, aorto-left circumflex coronary bypass with autogenous saphenous vein used as conduit was performed. Postoperatively multiple cerebral infarction ensued due to intraoperative hypovolemic shock and hypoxic brain damage during cardiopulmonary bypass. Currently, the patient's mental status is drowsy and in an improving state.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.367-370
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• 2006

The ballistic range has long been employed in a variety of engineering fields such as high-velocity impact engineering, projectile aerodynamics, creation of new materials, etc, since it can create an extremely high-pressure state in very short time. Two-stage light gas gun is being employed most extensively. The present experimental study has been conducted to develop a new type of ballistic range which can easily perform a projectile simulation. The ballistic range consists of a high-pressure tube, piston, pump tube, shock tube and launch tube. The experiment is conducted to find out the dependence of various parameters on the projectile velocity. The pressure in high-pressure tube, pressure of diaphragm rupture and projectile mass are varied to obtain various projectile velocities. This study also addresses the effect of the presence of a shock tube located between the pump tube and launch tube on system study. The experimental results are compared with those obtained through an author's theoretical study.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.263-266
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• 2007

The ballistic range has long been employed in a variety of engineering fields such as high-velocity impact engineering, projectile aerodynamics, creation of new materials since it can create an extremely high-pressure state in very short time. Two-stage light gas gun is being employed most extensively. The present experimental study has been conducted to develop a new type of ballistic range which can easily perform a projectile simulation. The experiment is conducted to find out the dependence of various parameters on the projectile velocity. The pressure in high-pressure tube, pressure of diaphragm rupture and projectile mass and piston mass are varied to obtain various projectile velocities. The flow field is visualized to see flow around projectile.

• Journal of Chest Surgery
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• v.38 no.7 s.252
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• pp.518-521
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• 2005

Pneumothorax associated with thoracic endometriosis is a rare clinical entity and it is called catamenial pneumothorax if the recurrence of pneumothorax is related to the period of menstruation. Several hypotheses about its pathogenesis are suggested including spontaneous rupture of the bulla, endometrial implants of the visceral pleura, and passage of air from the genital tract through endometrial fenestration of the diaphragm. Pneumothorax is associated with chest pain and dyspnea within 72 hours of the onset of menses in young women and developed usually at right side. We report a case of 32-year-old woman who had bilateral pneumothorax and thoracic endometriosis confirmed histopathologically in the visceral pleura by thoracotomy.

• Journal of Chest Surgery
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• v.40 no.1 s.270
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• pp.74-78
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• 2007

Systemic artery to pulmonary vessel fistula (SAPVF) is an abnormal communication between the systemic arterial circulation and the pulmonary circulation. Most SAPVF are congenital, but some SAPVF may also develop as a consequence of trauma, neoplasm, and inflammation of pleura or lung parenchyma. A 38-year-old man was referred to our department for hemoptysis. He underwent an operation for traumatic diaphragm rupture 16 years ago. Chest CT scan and angiography revealed SAPVF between several intercostal arteries and pulmonary vessels. He had an angiographic transcatheter embolization and the SAPVF disappeared at follow-up chest CT. To the best of our knowledge, this is the first case report of traumatic SAPVF in Korea.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.350-355
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• 2012

Past few years have seen the growing importance of micro shock tubes in various engineering applications. A pharma ballistic technique is one such application which uses micro shock tube to accelerate drug particles and penetrate into skin, thus avoiding the usual injection drug delivery system. But for the efficient design of such instruments requires the detailed knowledge of shock characteristics and flow field inside a micro shock tube. Due to many factors such as boundary layer, low Reynolds number and high Knudsen number shock propagation inside micro shock tubes will be quite different from that of the well established macro shock tubes. In the present study, experimental studies were carried out on a micro shock tube of 3 mm diameter to investigate flow characteristics and shock propagation. Pressure values were measured at different locations inside the driven section. From the experimental values other parameters like shock velocity, shock strength were found and shock wave diagram was constructed.

• Journal of Chest Surgery
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• v.31 no.8
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• pp.804-810
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• 1998

Background: Multiple trauma patients have rapidly increased due to traffic accidents, industrial disasters, incidental accidents, and violence. Multiple trauma can involve injuries to the heart, lung, and great vessels and influence the lives, necessitate prompt diagnosis and treatment. Most of the thoracic injuries can be managed with conservative method and simple surgical procedures, such as closed thoracostomy, but in certain cases open thoracotomy is necessary. Materials and methods: The author analyzed the surgical result of 70 cases of open thoracotomy after multiple organ injury including thoracic organ. Results: The most common type of thoracic lesion was hemothorax with or without pneumothorax and diaphragmatic rupture was the second. Sixty percent of the patients were associated with bone fractures, 42.9% with abdominal injuries, and 37.1% with head injuries. The modes of operation were ligations of torn vessels for bleeding control(48.6%), repair of diaphragm(35.7%), and repair of lung laceration(25.7%) in this order of frequency and additional procedures were splenectomy(14.3%), hepatic lobectomy (8.6%) and repair of liver lacerations(5.7%). Postoperative complications were atelectasis (8.6%), wound infection (8.6%), and pneumonia(4.3%). Postoperatively six patients died(The mortality rate was 8.6%) and the causes of death were respiratory failure(2), acute renal failure(2), sepsis(1), and hypovolemic shock(1).

• Journal of Veterinary Clinics
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• v.33 no.4
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• pp.237-242
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• 2016

A 1.86 kg, 3-year-old, female, Maltese was presented to the Veterinary Medical Teaching Hospital of Seoul National University after being hit by a car. The patient was diagnosed with urinary bladder rupture, diaphragmatic hernia and fracture of ilium, tibia and fibula. Repair surgery was performed after stabilizing treatment. During the surgery, hypoxia was identified and it worsened after positive pressure ventilation (partial pressure of oxygen in arterial blood ($PaO_2$): 52 mmHg, pulse oximetry ($SpO_2$): 87%, arterial hemoglobin oxygen saturation ($SpO_2$): 85.8%). In addition to hypoxia, blood pressure decreased to 30 mmHg. Positive pressure ventilation was discontinued because hypoxia and hypotension were aggravated. After suturing the diaphragm, air was withdrawn to form negative pressure within the thorax. However, negative pressure was not attained despite continuous withdrawal of air. A thoracostomy tube was placed because tension pneumothorax was strongly suspected. The patient recovered through close monitoring with the tube for 3 days. Due to limitation of evaluation of the lung, predicting occurrence of tension pneumothorax is difficult in patient of diaphragmatic hernia. Therefore, it is recommended that indicators of tension pneumothorax should be closely monitored during diagnosis and repair procedures of diaphragmatic hernia.