• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2007년도 추계학술대회 논문집
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• pp.213-216
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• 2007

The computer simulation for the fault current limiting characteristics of the superconducting fault current limiter (SFCL) using the magnetic coupling of two coils was performed. The magnetic fluxes generated from two coils were canceled out during a normal time. However, the resistance generation of high-$T_c$ superconducting (HTSC) element after a fault occurrence keeps up the magnetic fluxes of two coils and contributes to the fault current limiting operation. Through the computer simulation for the fault current limiting characteristics based on its electrical equivalent circuit, its operational current and the limiting impedance could be improved by adjusting the inductance ratio between two coils.

• Communications for Statistical Applications and Methods
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• 제15권5호
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• pp.727-735
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• 2008

Consider a clinical trial in which the main end-point is survival. Suppose after the start of the study an intermediate event occurs which may be influenced by a covariate(or treatment). In many clinical studies the occurrence of an intermediate event may change the survival distribution. This investigation develops two-stage model which, in the first stage, models the effect of covariate on the intermediate event and models the relationship between survival time and covariate as well as the intermediate event. In this paper, the two-stage model is presented in order to model intermediate event and a test based on this model is also provided. A numerical simulations are carried out to evaluate its overall significance level.

• 식물병과 농업
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• 제1권1호
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• pp.30-36
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• 1995

Infection rate of witches'-broom disease (WB) was observed yearly in transplanted jujube seedlings for 7 years. Seedlings of‘Hongan’grafted either on the rootstock from seed (RS) or on the rootstock from rooting (RR) were planted in separate farms. Occurrence of the disease was determined 4 years after transplanting with the witches'-broom symptom. Only 1 seedling of RS was infected with WB, while 56 seedlings of RR showed WB. Yearly infection rates of WB were observed in several varieties of jujube including‘Boeun’,‘Keumsung’,‘Moodeung’,‘Bokjo’,‘Koori’(10 trees for each in Cheongjoo), and‘Hongan’(165 trees in Boeun). In most varieties, WB first appeared in the third year from transplanting, and in the seventh year, more than 80% of the total tree showed WB. The yearly infection rate of newly infected trees was almost. stable during the first years. However, the ratio sharply increased from the sixth year. The accumulated infection rate of WB increased double, year by year from the third to seventh year. Between Cheongjoo and Boeun, no difference in infection rates was found.

• Journal of Chest Surgery
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• 제15권2호
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• pp.148-154
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• 1982

The experience with operative treatment for peripheral situated solitary circumscribed lesions of the lung at the Department of Thorac. & Cardiovasc. Surg., Korea University Hospital during 8 years from March 1974, through April, 1982 was reviewed. Our criteria for Solitary pulmonary nodule were 1. Round or Ovoid shape 2. Surrounded by normal lung Parenchyme 3. Well circumscribed peripheral location 4. No other visible pulmonary diseases on chest X-ray except minimal atelectasis or pneumonitis 5. Largest diameter less than 8 cm Of the 55 patients reviewed, there were 69% of malignancy and 31% of benign pulmonary diseases. In malignancy 38 patients, there were 18 patients with squamous cell carcinoma, 8 patients with undifferentiated large cell carcinoma, 2 patients with undifferentiated small cell carcinoma, 10 patients with adenocarcinoma and patient with metastatic carcinoma. In benign pulmonary nodule 17 patients, here were 5 patients with tuberculoma, 5 patients with aspergilloma, 2 patients with A-V fistula, 1 patient with pulmonary blastoma, 1 patient with paragonimiasis, and 1 patient with lung abscess. Overall male to female occurrence ratio was 39:16, and most prevalent age incidence was 7th decades. Most frequent size distribution was 4-6 cm in diameter. All of benign diseases were cured by resection and 66% of malignancy performed operation and has 75% resectability.

• Journal of Chest Surgery
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• 제24권11호
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• pp.1098-1106
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• 1991

Atelectasis may be defined as collapse of the lung due to absence of air within the alveoli. It may involve anatomic segments, lobes, or whole lungs but also may be a diffuse miliary process, as in the adult respiratory distress syndrome. The key to treatment are the anticipation and prevention of atelectasis in various clinical situations, the recognition and treatment of underlying disease, and the prompt initiation of vigorous treatment once atelectasis is found. Repeated assessment by physical examination is necessary to determine the presence of atelectasis and its response to treatment. During the period of January, 1981 to October, 1990, 100 patients with atelectasis were treated in the department of Thoracic and Cardiovascular Surgery, Pusan National University Hospital. There were 70 males and 30 females ranging from 3 days to 79 years of age. The occurrence ratio of right to left side was 2.1 : 1. The underlying pathologic lesions of atelectasis were pneumonia with effusion(28), lung ca.(24), pulmonary tuberculosis(24), and chronic empyema(9), The treatment procedure for atelectasis were closed thoracostomy in 26 cases, ressection in 21 cases, therapeutic bronchoscopy in 14 cases and etc.

• Journal of Chest Surgery
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• 제24권6호
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• pp.555-559
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• 1991

Post-pneumonectomy empyema thoracis is an uncommon, but very serious problem. Early diagnosis & adequate drainage followed by thoracoplasty and or myoplasty are very important principles for the management of the empyema thoracis & will enable patient to recover from the toxic effects. During the period of January, 1985 to December, 1990, 13 patients with post-pneumonectomy empyema thoracis were treated in the department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine. There were 10 males % 3 females ranging from 31 years to 79 years of age. The occurrence ratio of left to right side was 8: 5. The underlying pathologic lesions of empyema thoracis were pulmonary tuberculosis[7], lung ca. [2] pneumothorax[2], lung abscess[1] pneumonia[1]. We treatment procedure for post-pneumonectomy empyema thoracis were open window thoracostomy in 10 cases, Clagett procedures in 2 cases, one thoracoplasty, and two cases of Clagett procedures followed by open window thoracostomy in one cases.

• Journal of Chest Surgery
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• 제15권3호
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• pp.274-277
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• 1982

A Clinical analysis of 59 patients of thoracic empyema was done who were received surgical intervention at dept. of thoracic surgery of the C.A.F.G.H. in the period of 2.5 years from January 1979 to June 1982. Occurrence ratio of Left and Right side pleural cavity of empyema was 1: 1.4. The predisposing factors of empyema were pulmonary Tbc. [49%], Chest pain [25%], Cough [8%], in order. B.P.F. was associated with empyema in 5 cases. The pleural cavity empyema was treated with several surgical procedures and conservative measures. Among of the 59 cases, the 30 cases [50%] were treated with decortication, 12 cases [20%] with closed thoractomy drainage, 9 cases with frequent thoracenteses, 5 cases with partial decortication and thoracoplasty and 3 cases with open thoracostomy tube drainage. Among of the 59 cases thoracic empyema, the full recovery were in 32 cases [54%], partial recovery in 20 cases [34%], not improved in 3 cases [5%] and 3 cases were died. The mortality rate was 5% and the recovery rate was 89%.

• 한국항해학회지
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• 제20권1호
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• pp.47-58
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• 1996

The use of high tensile steel plates is increasing in the fabrication of ship and offshore structures. The main portion of ship structure is usually composed of stiffened plates. In these structures, plate buckling is one of the most important design criteria and buckling load may usually be obtained as an eigenvalue solution of the governing equations for the plate. To use the high tensile steel plate effectively, its thickness may become thin so that the occurrence of buckling is inevitable and design allowing plate buckling may be necessary. When the panel elastic buckling is allowed, it is necessary to get precise understandings about the post-buckling behaviour of thin plates. It is well known that a thin flat plate undergoes secondary buckling after initial buckling took place and the deflection of the initial buckling mode was developed. From this point of view, this paper discusses the post-buckling behaviour of thin plates under thrust including the secondary buckling phenomenon. Series of elastic large deflection analyses were performed on rectangular plates with aspect ratio 3.6 using the analytical method and the FEM.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.840-843
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• 2006

The aim of this study was to detect landslide using satellite image and apply the landslide to probabilistic landslide-susceptibility mapping at Gangneung area, Korea using a Geographic Information System (GIS). Landslide locations were identified by change detection technique of KOMSAT-1 (Korea Multipurpose Satellite) EOC (Electro Optical Camera) images and checked in field. For landslide-susceptibility mapping, maps of the topography, geology, soil, forest, lineaments, and land cover were constructed from the spatial data sets. Then, the sixteen factors that influence landslide occurrence were extracted from the database. Using the factors and detected landslide, the relationships were calculated using frequency ratio, one of the probabilistic model. Then, landslide-susceptibility map was drawn using the frequency ration and finally, the map was verified by comparing with existing landslide locations. As the verification result, the prediction accuracy showed 86.76%. The landslide-susceptibility map can be used to reduce hazards associated with landslides and to land cover planning.

• Journal of Chest Surgery
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• 제23권6호
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• pp.1213-1220
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• 1990

During the period of January 1979 to December 1988, 220 patients with empyema thoracis were treated in the department of Thoracic and Cardiovascular Surgery, Chonnam National University Medical School Hospital. There were 167 males[75.9%] and 53 females[24.1%] ranging from 18 days to 76 years of age. Occurrence ratio of left and right empyema was 1 : 1.9. The underlying pathologic lesions of empyema were pneumonia[30.9%], pulmonary tuberculosis[22.7%], chest trauma[8.6%] and postoperative complications. In bacteriologic study, staphylococcus, pseudomonas and streptococcus accounted for 26.4%, 11.8% and 9% respectively, and 25% were not identified. Surgical treatment modalities were thoracentesis[10 patients, 4.5%], closed thoracostomy[132, 60%], closed rib resection drainage[4.2, 6%], modified Eloesser’s operation[37, 16.8%], decortication[27, 12.3%], decortication with pulmonary resection[6, 2.7%], thoracoplasty[2, 0.9%], muscle flap closure [1, 0.5%], and staged pneumonectomy[1, 0.5%], The mortality rate was 2.3% and the complications were sepsis[9 patients]. acute renal failure[4], and paralytic ileus[3].