• Journal of Chest Surgery
• /
• 제17권1호
• /
• pp.110-117
• /
• 1984

A clinical evaluation was performed on 76 cases of chest injury experienced at department of Chest Surgery, Capital Armed Forces General Hospital during the past 3 years period from January 1981 to August 1983. 1.The most common cause of the chest trauma was gun shot by which 26 cases were injured among 44 cases [57.9%] of penetrating injury. Remaining 32 cases [42.1%] were injured by non-penetrating blunt trauma. 2.Hemopneumothorax was observed in 60 cases [78.9%], those were caused by both penetrating [65%] and non-penetrating [35%] injuries. 3.Rib fracture was found in 58.7% of total cases and with rib fracture, clavicle fracture was combined at 19.6% and sternal fracture, at 8.7%. 4.Most common symptoms were chest pain and dyspnea, and most common signs were breath sound diminution and subcutaneous emphysema. 5.Common site of rib fracture was from 4th rib to 8th rib [69.4%]. 6.In 58 cases [76.3%], patients were treated with operation including open thoracotomy [25 cases]. 7.Overall mortality was 5.3%[4 cases] and causes of death were septic shock and respiratory failure.

• 대한임상독성학회지
• /
• 제6권2호
• /
• pp.110-116
• /
• 2008

Purpose: Acute toxic hepatitis is a common cause of acute liver failure (ALF). We investigated the causes, clinical manifestation, and outcomes of ALF patients who underwent liver transplantation due to acute toxic hepatitis caused by herbal medicines and preparations. Methods: Between January 1992 and May 2008, we retrospectively reviewed the medical records of 24 patients who were transplanted due to acute toxic hepatitis caused by herbal medicines and preparations. We applied the RUCAM score to patients with acute toxic hepatitis and assessed the relationship between herbal preparations and liver injury. We studied the patients' medication history, liver function tests, and clinical outcomes. Results: The type of liver injury was divided into three groups: hepatocellular type, 14 patients (58.3%); cholestatic type, 4 patients (16.7%); and mixed type, 6 patients (25%). Polygonum multiflorum Thunberg (3 cases) was the most common cause of acute toxic hepatitis, followed by Acanthopanax senticosus (2 cases), pumpkin juice (2 cases), Dictamnus dasycarpus Turcz (2 cases), Hovenia dulcis (1 case), Phellinus linteus (1 case), and Artemisia capillaries (1 case). One year survival after liver transplantation was 76%. Conclusion: We identified the herbal preparations leading to acute liver failure. Many patients consider herbal remedies to be completely free of unwanted side effects. However, we found that many herbal products have biological activities that can lead to severe hepatotoxicity.

• Journal of Chest Surgery
• /
• 제27권8호
• /
• pp.650-655
• /
• 1994

The author analyzed 99patients with VSD weighting less than 10kg of body weight who underwent surgical correction from 1981 to 1992 at cardiovascular department of Hanyang University hospital. Patients occupied 29.3% of total cases who were underwent surgical corrections for congenital heart diseases during that time. Of the 99 patients, 51 patients were male [52%] and 48 patients[48%] were female. Age ranged from 28 days to 36 months with mean age of 13.6 months. Mean body weight was 7.53kg. According to Kirklin`s anatomical classification, type II defect was most common [61.6%]. Associated anomaly was found in 48 patients [48.5%]. Patent foramen ovale was most commonly associated cardiac anomaly [14.1%] and followed by atrial septal defect [12.1%], patent ductus arteriosus [10.1%]. Cardiac catheterization data were analyzed. The most common range of Qp/Qs, Rp/Rs, Pp/Ps were above 3.0, 0.1 - 0.25, and above 0.75 respectively. Among the indications of surgical correction, there were pulmonary hypertention in 69 patients, congestive heart failure in 44 patients, frequent respiratory infection in 47 patients, growth retardation in 33 patients. The most common surgical approach and method for VSD closure were right atriotomy[48.3%] and dacron patch closure[93.3%]. Complication rate was 13.1% [13 cases], and overall mortality was 17.1% [17 cases]. The cause of death consisted of low cardiac output syndrome[11 cases], acute renal failure[3 cases], sepsis[2 cases] and pulmonary insufficiency[1 case] in order of frequency.

• Journal of Chest Surgery
• /
• 제25권9호
• /
• pp.968-975
• /
• 1992

A clinical analysis was performed on 404 cases of the chest trauma who were admitted and treated at department of thoracic and cardiovascular surgery, Chung Ang University, Yong San Hospital during the past 8 years from July 1984 to April 1992. The results were as follows. 1. The sex ratio was 3: 1 with male predominence. 2. The common age groups were 3rd, 4th, 5th and 6th decades. 3. The most common chief complaint was chest pain[58.2%]. 4. Of 404 cases of chest trauma, 50 cases were resulted from penetrating injuries whereas 354 cases were from non penetrating injuries. The most common cause of the non penetrating injuries was traffic accident[234/354, 66.1%] and of the penetrating injuries were stab wound[47/50, 94%]. 5. The left thorax was the preferred site of chest trauma. 6. The range of hospital stay was from less than 1 week to over 6 weeks and the average duration was about 2 weeks. 7. The common chest trauma was rib fracture[51.6%] and others were simple contusion [18.8%], hemothorax[14.6%], hemopneumothorax[14.9%] and pneumothorax[8.7i]. The rib fracture was prevalent between 4th to 9th rib laterally. 8. There were 92 cases of associated injuries which were bone fracture[66/92, 71.7%], head injury[17/92, 18.5%] and abdominal injury[9/92, 9.8%]. 9. The methods of treatment were conservative management[58.6%], closed tho-racostomy[23.3%], open thoracotomy[3.4%] and others. 10. There were 28 cases[6.9%] of complication, such as pneumonia, atelectasis, emp-yema, respiratory failure and others. 11. The overall mortality was 2.5%[10 cases] and causes of death were hypovolemic shock, acute renal failure, adult respiratory distress syndrome, sepsis and multiple organ failure.

• Industrial Engineering and Management Systems
• /
• 제8권4호
• /
• pp.247-256
• /
• 2009

In mass production industries such as steel making that have large equipment, sudden stops of production process due to machine failure can cause severe problems. To prevent such situations, machine diagnosis techniques play important roles. Many methods have been developed focusing on this subject. In this paper, we propose a method for the early detection of the failure on rotating machine, which is the most common theme in the machine failure detection field. A simplified method of calculating autocorrelation function is introduced and is utilized for ARMA model identification. Furthermore, an absolute deterioration factor such as Bicoherence is introduced. Machine diagnosis can be executed by this simplified calculation method of system parameter distance with weight. Proposed method proved to be a practical index for machine diagnosis by numerical examples.

• International Journal of Control, Automation, and Systems
• /
• 제4권1호
• /
• pp.105-112
• /
• 2006

The main function of a reactor protection system is to maintain the reactor core integrity and the reactor coolant system pressure boundary. Generally, the reactor protection system adopts the 2-out-of-m redundant architecture to assure a reliable operation. This paper describes the safety assessment of a digital reactor protection system using the fault tree analysis technique. The fault tree technique can be expressed in terms of combinations of the basic event failures such as the random hardware failures, common cause failures, operator errors, and the fault tolerance mechanisms implemented in the reactor protection system. In this paper, a prediction method of the hardware failure rate is suggested for a digital reactor protection system, and applied to the reactor protection system being developed in Korea to identify design weak points from a safety point of view.

• 한국안전학회지
• /
• 제15권4호
• /
• pp.62-68
• /
• 2000

Static electricity in electronics manufacturing plants causes the economic loss, yet it is one of the least understood and least recognized effects haunting the industry today. Today's challenge in semiconductor devices is to achieve greater functional density pattern and to miniaturize electronic systems of being more fragile by electrostatic discharges(ESD) phenomena. As the use of automatic handling equipment for static-sensitive semiconductor components is rapidly increased, most manufacturers need to be more alert to the problem of ESD. One of the most common causes of electrostatic damage is the direct transfer of electrostatic charge from the human body or a charged material to the static-sensitive devices. To evaluate the ESD hazards by charged human body and devices, in this paper, characteristics of electrostatic attenuation in domestic semiconductor devices is investigated and the voltage to cause electronic component failures is investigated by field-induced charged device model(FCDM) tester. The FCDM simulator provides a fast and inexpensive test that faithfully represents ESD hazards in plants. Also the results obtained in this paper can be used for the prevention of semiconductor failure from ESD hazards.

• 한국신뢰성학회지:신뢰성응용연구
• /
• 제13권1호
• /
• pp.45-53
• /
• 2013

In this paper, we analyze the failure mechanism of the washer pump to find what is the failure cause in the road environment. The statistics show the field common failure mode is inner corrosion. The failure mechanism is assumed that the inner part of washer pump is corroded due to inflow of moisture through vent hole. To prevent the failure, we can think a method that is covering the vent hole. In general, the vent hole is designed to play an important role in an automobile parts. So, we need to prove the vent hole is not necessary. The first purpose of this paper is to make sure that the vent hole does not affect the durability of washer pump using the analysis of operating condition. The second purpose is to compare the durability properties if the vent hole is covered.

• Journal of Chest Surgery
• /
• 제18권1호
• /
• pp.111-121
• /
• 1985

A clinical analysis was performed on 312 cases of the chest trauma experienced at department of thoracic surgery, Chosun University Hospital during the past 6 years 10 months period from January 1978 to October 1984. 1. The ratio of male to female patient of the chest trauma was 3.1:1 in male predominance and age from 20 to 50 occupied 71.2% of the total cases. 2. The most common cause of the chest trauma was traffic accidents [45.5%] in this series. 244 cases [78.2%]were injured due to non-penetrating injuries and the remainders [68 cases, 21.8%] were injured due to penetrating injuries. 3. The frequently injured site of the chest trauma was left side of the chest [56.4%], the right side was 33% and the both side was 10.6%. 4. The most common symptoms were chest pain and dyspnea, and common signs were diminished breathing sound and subcutaneous emphysema. 5. The Hemothorax, Pneumothorax, Hemopneumothorax, and Hemopericardium were observed in 190 cases [60.9%] of the total cases, and etiologic distribution revealed 76.5% due to penetrating injuries and 56.6% due to non-penetrating injuries. 6. The rib fractures were observed in 210 cases [67.3%] of the total cases and the most common site of the rib fracture was 6th rib 140 cases [19.2%]. The common site of the rib fracture was from 4th rib to 7th rib [63.8%]. 7. The lung injuries were observed in 150 cases [48.1%] and the other organ injuries were observed in 260 cases [83.3%]. 8. Conservative treatment including thoracentesis were performed in 153 cases [49.1%], Closed thoracotomy with water seal drainage were performed in 112 cases [35.9%], and open thoracotomy were performed in 45 cases [14.4%]. 9. The complications of the chest trauma were developed in 63 cases [20.2%] and the common complications were atelectasis, wound infection and pneumonitis etc. 10. Overall mortality was 0.96% [3 cases] and the cause of death was bacteremia, hypovolemic shock, heart failure and pulmonary edema.

• 산업경영시스템학회지
• /
• 제16권27호
• /
• pp.11-19
• /
• 1993

본 논문에서는 여러 가지 형태의 고장을 갖는 동일한 두 요소로 구성된 병렬 시스템의 신뢰도를 평가하는 마코프 모형을 제시하였다. 여기서 고려하는 고장형태는 인간의 오류에 의한 고장, 하드웨어에 의한 고장, 하나의 원인에 의해서 여러개의 구성요소가 동시에 고장나는 Common cause 고장형태로 나누었다. 시스템은 임의의 시점에서 예방보수를 받을수 있고, 고장률과 예방 보수률은 일정하다고 가정했다. 또한 수리률이 임의의 분포를 따를 경우 시스템 신뢰도 및 평균 고장시간을 구했다.