• 산업공학
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• 제17권spc호
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• pp.11-19
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• 2004

The purpose of this study is to identify the determinants of new venture performance according to years of operation in the view of integrated research framework. We propose the integrated new ventures performance model which is composed of entrepreneur, organization/resources, industrial environment, strategy/foundation process and availability of supporting systems as corresponding variables to new ventures performance. The determinants of new venture performance according to years of operation are identified through the multi-variate statistical analysis such as moderating regression analysis with the data gathered from 110 executives of venture companies. For internal variables, entrepreneur's managerial ability and technical expertise and employee's ability affect venture's performance increasingly as years of operation increases but resource procurement ability affects decreasingly. Related to external variables, years of operation plays positive moderating role on market size growth and supporting system availability, but negative role on government venture policy for venture performances. Though this study has limitation of small sample, limited questionnaire and performance measure, it has managerial contribution of identifying determinants of new venture performance according to years of operation.

• Journal of Chest Surgery
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• 제26권8호
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• pp.595-603
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• 1993

We analysed 60 consecutive patients who got Senning operation for transposition of the great arteries [TGA] with or without ventricular septal defects [VSD]. There were 41 simple TGA [group I] and 19 TGA with VSD [Group II], the operative mortality was 20 % [in group I 4.9 %, group II 52.6 %]. Among the survivors [n=48], the mean follow-up period was 7 years [range, 1 year to 13.5 years] and the actuarial survival rate at 13 years were 95 % in group I and 42 % in group II. Preoperative high left ventricular pressure and high pulmonary arterial pressure affected the surviving [p<0.01]. There occurred various type of arrhythmia like junctional rhythm, first degree atrioventricular [AV] block, sick sinus syndrome and complete AV block, and we inserted 2 permanent pacemakers for these patients. The incidence of arrhythmia were 28.2 % [11/39] in group I and 55.6 % [5/9] in group II, and the actuarial freedom from arrhythmia at 13 years after operation was 66 % [71 % in group I, 44 % in group II]. Increased aortic cross clamping time had affected the development of arrhythmia [p<0.05] which meant the complexity of the operation. The total incidence of left ventricular outflow tract obstruction [LVOTO] was 31.3 % [15/48], but only 3 patients [6.25 %] showed the significant gradient requiring reoperation. The pulmonary venous pathway obstruction [PVO] were found in 3 patients, all in group I, and among them only one required the reoperation. The estimated freedom from PVO was 89 % at 13 years [87 % in group I, 100 % in group II], but we couldn`t find any significant systemic venous obstruction in our series. There occurred 27.1 % [13/48] mild degree tricuspid valve regurgitation without necessary surgical correction. We experienced 14.6 % [7/48] reoperation rate: 3 residual VSD, 3 LVOTO, 1 PVO, 3 atrial baffle leakage. For this high incidence of complication rate after Senning operation and high mortality in TGA with VSD, We do not use this kind of surgical modality any more and do the Jatene operation for all the TGA patients since several years ago.

• Journal of Chest Surgery
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• 제12권2호
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• pp.82-88
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• 1979

During the past 3 years, 15 patients who could not be anesthetized generally because of poor general condition or cachecic state, of 111 patients with empyema, have been treated with modified Eloesser`s operation under the local anesthesia with 2% procaine. There were 13 males and 2 females ranging from 21 years to 61 years of age. The etiology was tuberculosis [6 cases], pyogenic pneumonia [5 cases], lung abscess [1 case], post-trauma [2 cases] and malignancy[1 case]. " The over-all mortality rate was 6.7%[1 case] and cause of its death was poor oral feeding because of post-traumatic psychosis. Modified Eloesser`s operation was performed after closed tube thoracostomy and irrigation with 1% zephanon solution for over 2 weeks. And then the other operation was not performed and all patients except 1 case appeared good progression (Complete healing; 4 cases, Progressive healing 10 cases, death: 1 case).

• Advances in pediatric surgery
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• 제13권2호
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• pp.105-111
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• 2007

We reviewed the records of 25 patients who were re-operated upon after primary repair of esophageal atresia with or without fistula at the Department of Pediatric Surgery, Seoul National University Children's Hospital, from January 1997 to March 2007. Types of the esophageal atresia anomalies were Gross type A in 5 patients, C in 18, and E in 2. The indications for re-operation were anastomosis stricture (n = 14), tracheo-bronchial remnant (n = 4), persistent anastomosis leakage (n = 3), recurrent tracheo-esophageal fistula (n = 2) and esophageal web (n = 2). The interval between primary and secondary surgery was from 48 days to 26 years 5 months (mean: 2 years and 4 months). Four patients required a third operation. The interval between the second and third operation was between 1 year 1 month and 3 year 10 month (mean: 2 years 5 months). Mean follow up period after last operation was 35 months (1 years-8 years 6 months). The secondary surgery was end-to-end esophageal anastomosis in 15, esophagoplasty in 5, gastric tube replacement in 5. After secondary operation, 6 patients had anastomosis stricture (4 patients were relieved of the symptoms by balloon dilatation, 2 patients underwent tertiary operation). Five patients had leakage (sealed on conservative management in all). Two patients had recurrent tracheo-esophagel fistula (1 patient received chemical cauterization and 1 patient underwent tertiary operation). Currently, only one patient has feeding problems. There were no mortalities. Secondary esophageal surgery after primary surgery for esophageal atresia was effective and safe, should be positively considered when complications do not respond to nonoperative therapy.

• 한국국방경영분석학회지
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• 제16권2호
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• pp.1-13
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• 1990

The life of an equipment depends upon its operating characteristics and physical environment factors. This paper presents the economic life length of 2 1/2 ton truck considering the operation terrains. For this specific research, the operation terrains are categorized into seacoast area, mountain area and plain area. To compute the life length, the method of equivalent annual cost is employed. The sample vehicles from each corresponding area are randomly selected from those vehicles whose ages exceed 9 years. This research finds the following results : (1) The life length operated at seacoast area is 9.75 years, (2) The life length operated at mountain area is 11.25 years, (3) The life length operated at plain area is 14 years. This research argues that the key factor such as characteristics of operating enviroment for allocation of operating and maintaining cost should be considered.

• Journal of Chest Surgery
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• 제24권2호
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• pp.135-142
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• 1991

From January 1980 to December 1989, thirteen patients underwent operation for ventricular septal defect associated with aortic insufficiency in Kyungpook national university hospital. Ten male and three female patients ranged in age from 3 years to 25 years, with an average age of 11.5 years. Aortic cusp prolapse was found in eight cases[61.5%]. The aortic regurgitation was classified by Sellers` method with grade I in 2 cases, grade II in 9 cases, and grade III in 2 cases. Direct suture or patch repair of ventricular septal defect was performed through the right ventricle. Eight cases were treated only by closure of VSD, 3 cases by plication, but two of the letter were reoperated due to the persistent of aortic regurgitation and fungal endocarditis respectively. Aortic valve replacement were performed in 2 cases at the first operation. There was only one late death[7.7%], which was caused by postoperative fungal endocarditis. Follow-up for twelve patients except one death were followed up for 3 months to six years after operation. Residual aortic regurgitation was noted in six cases[46.2%], but the postoperative course of them were uneventful.

• Advances in pediatric surgery
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• 제13권1호
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• pp.1-12
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• 2007

Biliary atresia (BA) is the result of fibrosing destructive inflammatory process affecting intrahepatic and extrahepatic bile ducts, which lead to cirrhosis and portal hypertension. Kasai portoenterostomy has been the standard operative procedure in biliary atresia. Recently, there has been remarkable increase in the survival rate in cases of BA. However, long-term survivors are not clearly evaluated in Korea. To define long-term prognosis factors of patients who underwent surgery for BA, a retrospective study was undertaken of 10 (37 %) patients surviving more than 10 years among 27 patients who underwent one of Kasai procedures between 1981 and 1995. Hepatomegaly was present in 4 and splenomegaly in 7 patients. Serum bilirubin was normalized at 1 year after operation. Aspartate aminotransferase (AST, GOT), Alanine aminotransferase(ALT, GPT) were normalized at 12 years and alkaline phosphatase(ALP) was normalized at 13.5 years. Cholangitis developed mainly within 5 years after operation so close follow up is needed. Life long follow-up is needed because of progressive deterioration of liver function even after 10 years.

• Journal of Chest Surgery
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• 제18권1호
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• pp.86-91
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• 1985

A clinical analysis was performed on 11 cases of metastatic lung cancer experienced at Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital during the 15 year period from 1970 to 1984. Of the 1lpatients of metastatic lung cancer, 4 patients were male and 7 patients were female and the age ranged from 27 years to 60 years old with the average of 38.8 years old. The sites of primary tumor were uterus and ovary in 5 patients, breast in 2, sarcoma in 2, rectum in 1 and testis in l.\ulcorner Tumor free intervals in each patients were as followed; unrecognition of primary site in 2 patients, simultaneous discovery of primary tumor and metastasis in 3, 14 months in 1, 4 years in 4 and 5 years in Twelve thoracotomies were performed in 11 patients and performed procedures were as followed; pneumonectomy in 1 patient, lobectomy in 7, wedge resection in 2, decortication and wedge resection in 1 and biopsy only in 1. Of the 11 patients, 4 patients died within one year after operation, 2 patients died within 2 years and 2 patients are alive over 5 years after operations. Other 3 patients are alive 2 months, 4 months and 9 months after operation at present.

• 대한골관절종양학회지
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• 제1권1호
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• pp.30-37
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• 1995

The prognosis of parosteal osteosarcoma is better than any other malignant bone tumors, but there are many controversies in its treatment. We tried to evaluate the prognosis and the effectiveness of limb-salvage operation in the treatment of the parosteal osteosarcoma. We experienced 12 patients of conventional parosteal osteosarcoma(2 males and 10 females) from 1981 to 1991. The limb-salvage operations with wide resection margin were done in 8 patients(5 tumer prosthesis, 2 resection arthrodesis and 1 vascularized fibular transplantation), marginal en-bloc resection and amputation in 2 patients, respectively. The duration of mean follow up was 5 years and 9 months, ranging from 2 year-3 months to 11 years, except of the patient who died with metastasis 1 year 8 months after. The disease-free survival rate(DFSR) of all patients was 68% and that of the patients treated with limb-salvage operation was 88% at 7 years. The DFSR was 33% with marginal margin(3 cases) and 89% with wide margin(9 cases) at 7 years. The results were unsatisfactory in the conventional parosteal osteosarcoma treated with marginal resection. The limb-salvage operation with wide surgical margin was thought to be the treatment of choice.

• Architectural research
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• 제7권1호
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• pp.11-18
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• 2005

In today's building industry the emphasis has been geared more towards construction, thus building maintenance and life cycle have been neglected until now. A direct result of this neglect is the rapid aging of building, which leads to more cost-effective decision making methods for the prolongation of building life span. The following study is conducted in the area of Daegu and Seoul in order to develop the estimation analysis method of the annual operation cost of the Korean high-rise condominiums for the cost-effective decision making support through mathematical and statistical analyses including the present value and standardized measurement corrections. Based on the assumption that the life expectancy of the high rise condominium is 50 years, initial cost is ￦421,212/$m^2$, and a total sum of yearly operation cost during life expectancy is ￦2,154,499//$m^2$), yearly accumulated operation cost is shown as below: $AOC=0.7097t^4-38.803t^3+806.95t^2+11045t-496.52$ ($R^2=0.98$) (Here, AOC = Accumulated Operation Cost, t = given years)