• Journal of the Korean Operations Research and Management Science Society
• /
• v.24 no.4
• /
• pp.27-47
• /
• 1999

Many enterprises are interested in using the IS development methodologies as a means of increasing system performance and solving the problems of delayed delivery time, excessive budget, and failure of integrated systems. Even if previous researches showed that the system productivity and quality improvement using the system development methodologies are very poor, we tried to find that the methodologies are meaningful as an innovative means for IS performance. We defined that the IS development methodology as a technical and managerial innovation for IS department. We intended to study the relationship between the implementation process of the IS development methodology divided into four steps and IS performance. A cross-sectional field survey with IS departments of domestic companies was conducted, and we used LISREL 8.12a to perform the structural equation model analysis and hypothesis verification. We found the meaningful relationship between the development methodology and qualitative performance. We reconfirmed that the relationship between the development methodology and quantitative performance is not meaningful as expected, which is the same result with the previous researches. But the qualitative performance affects very strongly to the quantitative performance. As a results, we suggest that IS managers and developers keep the principles of the IS development methodologies to get the quantitative performance through the qualitative performance improvement.

• Annals of Clinical Neurophysiology
• /
• v.17 no.1
• /
• pp.24-27
• /
• 2015

Amyloidosis is a systemic disorder associated with clonal plasma cell dyscrasia. Nephrotic syndrome, congestive heart failure, autonomic and peripheral neuropathy is often associated features in amyloidosis. Early diagnosis is most important because of different prognosis by stage. The diagnosis can be delayed since symptoms of amyloidosis may vary or nonspecific. We describe a patient of myeloma-associated amyloidosis, who showed orthostatic intolerance as the first symptom of the disease.

• Clinical and Experimental Pediatrics
• /
• v.54 no.2
• /
• pp.86-89
• /
• 2011

Traumatic ventricular septal defect (VSD) resulting from blunt chest injury is a very rare event. The mechanisms of traumatic VSD have been of little concern to dateuntil now, but two dominant theories have been described. In one, the rupture occurs due to acute compression of the heart; in the other, it is due to myocardial infarction of the septum. The clinical symptoms and timing of presentation are variable, so appropriate diagnosis can be difficult or delayed. Closure of traumatic VSD has been based on a combination of heart failure symptoms, hemodynamics, and defect size. Here, we present a case of a 4-year-old boy who presented with a traumatic VSD following a car accident. He showed normal cardiac structure at the time of injury, but after 8 days, his repeated echocardiography revealed a VSD. He was successfully treated by surgical closure of the VSD, and has been doing well up to the present. This report suggests that the clinician should pay great close attention to the patients injured by blunt chest trauma, keeping in mind the possibility of cardiac injury.

• Korean Journal of Bronchoesophagology
• /
• v.14 no.1
• /
• pp.59-64
• /
• 2008

Pure esophageal atresia without tracheoesophageal fistula is a uncommon form of congenital malformation of the esophagus, which is able to be suspected by fetal ultrasonograpy before delivery and diagnosed definitely by simple chest X-ray and esophagogram immidiately after delivery. We performed delayed primary repair in 2 cases of pure esophageal atresia by using stomach for conduit in one case and colon in the other case. But there were graft failure in the latter case, so reoperation was performed by using stomach. Postoperatively, two patients showed no stenosis and leakage in anastomotic site and were discharged in good oral intake without dysphagia.

• Journal of Chest Surgery
• /
• v.47 no.5
• /
• pp.468-472
• /
• 2014

Diffuse refractory vascular spasms associated with coronary bypass artery grafting (CABG) are rare but devastating. A 42-year-old male patient with a past history of stent insertion was referred for the surgical treatment of a recurrent left main coronary artery disease. A hemodynamic derangement developed during graft harvesting, necessitating a hurried initiation of cardiopulmonary bypass (CPB). Although CABG was carried out as planned, the patient could not be weaned from the bypass. An emergency coronary angiography demonstrated a diffuse spasm of both native coronary arteries and grafts. CPB was switched to the femorofemoral extracorporeal membrane oxygenator (ECMO). Although he managed to recover from heart failure, his discharge was delayed due to the ischemic injury of the lower limb secondary to cannulation for ECMO. We reviewed the case and literature, placing emphasis on the predisposing factors and appropriate management.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.66 no.1
• /
• pp.21-26
• /
• 2017

Failure of high-voltage transmission line, which is responsible for large-scale power transmission, can be reason for system voltage instability. There are many methods to prevent voltage instability like adjustment of equipment, the generator voltage setting, and load shedding. Among them, the load shedding, have a problem of economic loss and cascading effect to power system. Therefore, the execution of load shedding, amount and timing is very important. Conventionally, the load shedding setting is decided by the preformed simulation. Now, it is possible to monitor the power system in real time by the appearance of PMU(Phasor Measurement Unit). By this reason, some of research is performed about decentralized load shedding. The characteristics of the load can impact to amount and timing of decentralized load shedding. Especially, it is necessary to consider the influence of the induction motor loads. This paper review recent topic about under voltage load shedding and compare with decentralized load shedding scheme with conventional load shedding scheme. And simulations show the effectiveness of proposed method in resolving the delayed voltage recovery in the Korean Power System.

• Journal of Korean Society of Steel Construction
• /
• v.21 no.3
• /
• pp.311-320
• /
• 2009

This paper presents the experimental results of an experiment on the current rectangular CFT columns and rectangular CFT columns additionally confined by carbon fiber sheets(CFS) under axial loading. The main experimental parameters were the layer numbers of the CFS and the depth-to-thickness ratio. Nine specimens were prepared according to the experimental parameter plans, and axial compression tests were conducted. From the tests, the failure procedure, the load-axial deformation curve, the maximum axial strength, and the deformation capacity of the CFT columns and the confined CFT columns were compared. Finally, it was seen that the maximum axial strengths of the CFT increased more significantly than that of the current CFT columns because of delayed local buckling.

• Journal of Chest Surgery
• /
• v.26 no.7
• /
• pp.526-531
• /
• 1993

Sixty-one consecutive patients with coronary artery bypass graft for myocardial revascularization were retrospectively reviewed to analyze various pattern of postoperative complication and death during hospital stay from Nov. 1988 to Oct. 1992. Fortytwo of the patients were male and nineteen female. The mean age was 56 and 51 years in male and female. Preoperative diagnosises were unstable angina in 14 of patients, stable angina in 28, postmyocardial infarction state in 15, and state of failed percutaneous transluminal coronary angioplasty in 4. 141 stenosed coronary arteries were bypassed with use of 20 pedicled internal mammary artery and 124 reversed saphenous vein grafts. Postoperative complications and perioperative death were as follows: 1. Of 61 patients undergoing operation, peri and postoperative over all complication occured in 15 patients [ 25% ]; newly developed myocardial infarction in 4, intractable cardiac arrhythmia including atrial fibrillation and frequent ventricular premature contraction in 3, bleeding from gastrointestinal tract in 2, persistent vegetative state as a sequele of brain hypoxia in 1, wound necrosis in 1, left hemidiaphragmatic palsy in 3 and poor blood flow through graft in 2. 2. Operative mortality was 8%[5 patients]. 3 out of these died in operating room; 1 patient by bleeding from rupture of calcified aortic wall, 1 by air embolism through left atrial vent catheter, 1 by low cardiac output syndrome. 2 patients died during hospital stay; 1 by acute respiratory distress syndrome with multiuple organ failure, 1 by brain death after delayed diagnosis of pericardial tamponade.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.2 no.1
• /
• pp.99-103
• /
• 1999

Duodenal web is an uncommon lesion that infrequently cause partial or complete intestinal obstruction. If the duonenal web is incomplete and only partially obstructs the duodenal lumen, the onset of symptoms may be delayed for years, and obstructive symptoms will be only minimal and intermittent. Congenital duodenal obstruction is occasionally associated with intestinal malrotation. We experienced a case of duodenal web associated with intestinal malrotation in a 9-year-old girl who had been suffered from intermittent projectile vomiting since birth without failure to thrive. The diagnosis was made by UGI series & abdominal CT. Patient remained asymptomatic after operation.

• Advances in pediatric surgery
• /
• v.14 no.2
• /
• pp.189-195
• /
• 2008

Colorectal cancer is extremely rare in children. Unlike adult colorectal cancer, the overall prognosis of colorectal cancer in children is poor. Delayed diagnosis, advanced stages of the disease at presentation, and mucinous type of histology are the major determinants of poor outcome in childhood. A 13-year-old boy with abdominal pain visited our hospital. Physical examination andabdominal ultrasonography identified acute appendicitis with perforation. He underwent appendectomy and then the pathologic findings revealed mucinous adenocarcinoma. The cancer was located at the transverse colon and had metastases on peritoneal wall at $2^{nd}$ laparotomy. Extended right hemicolectomy was performed. He underwent palliative chemotherapy. After 4 months later, hepatic metastasis and aggravated peritoneal seedings developed. He died of renal failure and pneumonia 13 months after operation. We need to have a high index of suspicion for the possibility of a malignant colorectal tumor in any childhood case with nonspecific signs and symptoms.