• Proceedings of the KSR Conference
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• 2003.10c
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• pp.145-150
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• 2003

The national subway went under construction in 1971, and after three years of endeavor, Seoul subway line number one opened for traffic in 1974. Line number two went under construction in 1978 and it opened for traffic in 1984. With the use of safety operation for more than 20 years, the life cycle nearly came to an end. Therefore the improvements for the safety operation are unavoidable. The total system should not be affected when the new and conventional systems are overlapped, the system operation is in the initial stage, and it confronts the situation of abnormal operation. However, there is a total lack of experience in construction and improvement for the trains that are in the use of large transport and density headway. In this paper, we propose an improvement method of the subway signalling system using ATO (Automatic Train Operation control scheme) to which the latest Digital ATC is applied, and examine the first application model of ATO system.

• Journal of Chest Surgery
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• v.24 no.7
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• pp.701-711
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• 1991

We experienced 6 cases of primary cardiac tumor, all received operation for removal of tumor. Mean age was 43.8 years-old ranging from 17 years-old to 66 years-old. Five cases were female, one case was male. Five cases were benign, myxoma, all located within left atrium. One case was malignant, angiosarcoma within right atrium. All patient showed cardiac manifestations. One case was in NYHA functional class II, two were in III, three were in IV. Four patients showed constitutional symptoms, but no one showed evidence of embolic phenomenon. All case of myxoma showed cardiomegaly except one malignancy. Only one case was regular sinus rhythm, three were sinus tachycardia 8z two were atrial fibrillation. The most common site of tumor origin was fossa ovalis limbus[four of all]. Two of five myxomas received emergency operation, one patient died postoperatively. Lived four patients showed no evidence of recurrence[mean follow-up, 3,5 years], but one patient has Grade II /IV mitral regurgitation & in OPD follow-up now, One malignant case, 17 years-old cerebral palsy female, was angiosarcoma occupied most of right atrial chamber originated from anterior wall of right atrium, received emergency operation which was removal of mass & reconstruction of right atrium with artificial pericardial patch. This patient died on postoperative 36th day due to persistent LCOS[low cardiac output syndrome] with combined sepsis.

• Nuclear Engineering and Technology
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• v.40 no.4
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• pp.277-284
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• 2008

Recently, the long-term operation of a nuclear power plant beyond its licensed term has become a worldwide trend as long as the safety of the plant is maintained in the extended period. Kori Unit 1, the oldest PWR in Korea, is the foremost example of this type of long-term operation in Korea. Comprehensive technical evaluation of the long-term operation of this plant was completed to confirm the overall safety of the plant. The technical evaluation included a review of PSR results, an assessment on aging management programs and time limited aging analyses, and a statement of radiological impact on the environment. Based on all of the results of the technical evaluation activities, Kori Unit 1 was approved to operate for an additional 10 years beyond its original design life of 30 years.

• The Journal of the Korean dental association
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• v.22 no.12 s.187
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• pp.1043-1046
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• 1984

The clinical and statistical evaluation on the patients of maxillofacial deformities who were operated by author were analyzed after several month or years or se. Pre and post operative cephalometric radiographs of 45 orthognathic surgery patients were compared. The post operative radiographs had been taken at least 9 month to several years. Measurements were made between constructed hard tissue and soft tissue points located on each before and after film tracing. The items studied and evaluated are as follows: 1) Classification and divid of patients 2) Operation technic adopted by operator. 3) Motives of patients for operation and their untowards. 4) Self satisfication of patients after operation. 5) Post operative changes of soft and hard tissue. 6) Side action during and after operation.

• Journal of Chest Surgery
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• v.37 no.1
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• pp.72-75
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• 2004

The Fontan operation is commonly practiced for the physiologic correction of univentricular heart diseases. However, for the patients who have risk factors against this operation, it is recommended to take the initial palliative operation rather than going to the Fontan operation at once. The proper timing to the Fontan operation after palliation is decided by assessing several factors such as patient's age and other risks of maintaining palliative state, etc. Usually, the Fontan operation is done relatively early after palliation stage. Here, we report a 36 years old-adult-female with univentricular heart disease who underwent the successful Fontan operation at 17 years after unidirectional Glenn procedure.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.653-660
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• 2007

South and North Koreas are putting forth efforts to overcome the distrust and animosity of the past 50 years to open an era of harmony and cooperation where the two halves can work together for mutual benefits. As part of those efforts, both parties are working now to reconnect the railways between the North and the South that remained broken for the past 60 years. The South and North have had different railway systems for more than 50 years. To solve these complicated issues, appropriate investigation and analysis of North Korea railway system should be proceeded. It is necessary to study the railway system and integration methodology for effective operation of the two korea's railway systems. Therefore, in this study, effective unification scheme of South and North Korea railway system is proposed based on appropriate investigation about operation of inter-Korea railway system.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1157-1158
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• 2015

This work is to study the effect of load current on 6.6 kV power cables in operation. In order to figure out the relationship between load current and temperature of the power cables, we have developed measuring equipment for insulation resistance, temperature, and current tested on 9 cables at power station, Western Power Co. Ltd. The cables used in our test were in operation for the last 18 years. Our research over a year showed that the remaining lifetime of 8 cables was more than 20 years. The remaining lifetime of one cable was about 16 to 18 years.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.1
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• pp.57-68
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• 2021

In order to collect basic data for the improvement of fishing systems in coastal improved stow net fishery, a questionnaire survey and on-site hearing were conducted from May 10 to June 11, 2019 on the basic items of coastal improved stow net fishery and safety accidents that occurred during fishing operation. The questionnaire for the survey on the actual conditions of coastal improved stow net fishery consisted of a survey on basic matters (six questions) and a questionnaire (six questions) on safety accidents occurring during fishing operation. The results of the survey on basic items were analyzed by region (Incheon, Seocheon, Gunsan and Mokpo), by the captain's age (less than 50 years of age, 50 to 60 years and more than 60 years of age), by the captain's career (less than 20 years, 20 to 30 years, 30 to 40 years and more than 40 years) and by the age of fishing vessel (less than 10 years, 10 to 20 years and more than 20 years). According to the survey on basic items of coastal improved stow net fishery such as the captain's age, the captain's career, the age of fishing vessel, the fishing nets in use, the crews on board and the operation days per voyage by region, the average captain's age was 55.7 years, the average captain's career was 20.5 years, the average age of fishing vessels was 9.0 years, the average numbers of nets used by fishing boats was 14.0 sets, the average numbers of crew on board a fishing boat was 4.4 persons and the average numbers of operation days per voyage was 4.9 days (p < 0.05). As a result of the survey on safety factors during fishing operations, such as experience of ship accidents, major causes of ship accidents experienced, causes of ship accidents (first priority), experience of human accidents, major causes of human accidents, and causes of human accidents (first priority), more than 96% of the respondents experienced ship accidents including collisions with other vessels or fishing gear during fishing operations. The most significant cause of the accident was the other's fishing gear installed in the fishing grounds. The first possible causes of ship accidents during fishing operations were found to be other fishing gear installed in fishing grounds, steering or engine failure, and inability to avoid accidents during casting and hauling nets. The survey of the experience of human accidents, such as injuries or sea falls, showed that more than 90% of the respondents experienced human accidents during fishing operations. The most important cause of accidents experienced during fishing operations was stucked in a fishing gear during casting and hauling nets. The first important causes of accidents during fishing operations were movement of the fishing gear during casting and hauling nets, damage of the fishing gear such as rope cutting. The results are expected to be provided as a basic data to prevent safety accidents occurring during fishing operation and improve the fishing system in the coastal improved stow net fishery.

• Advances in pediatric surgery
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• v.11 no.2
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• pp.131-140
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• 2005

The purpose of this study is to review the operative management and outcome of operation for Crohn's disease. The medical records of 17 patients who underwent operations for Crohn's disease at Seoul National University Children's Hospital from January of 1988 to June of 2005 were reviewed. The male-to -female ratio was 1.8: 1. The median age at the onset of symptoms and the time of diagnosis was 9 years 6 months and 11 years 6 months respectively. The median time interval from diagnosis to operation was 2 years and 1 month (0 month~8 years). The ileocolic or ileocecal region was the most common site of involvement. The indications for operation were intractable symptoms (8 cases) and obstruction or stricture (7 cases). The median postoperative hospitalized days were 14.4 days (8~35 days). Five patients (29 %) experienced postoperative complications. Symptom free state or symptom relief was observed in 11 cases after surgery and 6 cases had intermittent episodes of remissions and recurrences. In pediatric Crohn's disease patients who present with intractable symptoms despite medical treatment or develop surgical complications, symptom free state or symptom relief can be achieved by minimal resection of the diseased segment.

• Advances in pediatric surgery
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• v.10 no.1
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• pp.1-8
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• 2004

A re-pull-through operation for Hirschsprung's disease is performed when the primary operation has failed because of the remnant or acquired aganglionosis, anastomotic stricture and/or fistula. The purpose of this study is to review our experience of the re-pull-through procedure for Hirschsprung's disease. From May 1978 to July 2003, 26 patients who underwent re-pull-through operations at the Department of Pediatric Surgery, Seoul National University Children's Hospital, were studied retrospectively by means of chart review as well as telephone interview. The mean age at primary operation and re-operation were llmonths (2 months - 10 years) and 43 months (1 year - 23 years 3 months), respectively. Initial operation for Hirschsprung's disease was Duhamel's procedure in 17, Swenson's in 6 and Soave's 3. Causes of failure of primary operation were remains of secondary aganglionic segment (n=23), vascular arcade injury (n= 1), rectoperineal fistula (n=2, due to mesenteric torsion and poor blood supply), Mean interval between the primary operation and the re-operation was 34 months (6 months-22 years). Reoperation methods were Soave's in 12, Duhamel's in 8, APSP (abdomino-posterosagittal pull-through procedure) in 5, and Swenson's in 1 case. In 2 cases of repeated rectoperineal fistula or rectourethral fistula, re-APSP were performed 3 times, respectively. A total of 29 re-pull-through operations were performed. Postoperative complications were wound infection (n=1), adhesive ileus (n=1), rectoperineal fistula (n=3), rectourethral fistula (n=2), and death due to pulmonary embolism (n=1). Mean follow up period of reoperation was 78 months (1 month-23years). In current state, 2 patients have an ileostomy because of repeated rectoperineal fistula and rectourethral fistula. Of the remaining 23 patients, 21(91 %) are totally continent with or without minimal soiling. Reoperation for Hirschsprung's disease was effective and safe for the patients complicated to the initial pull-through operation.