• ETRI Journal
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• 제27권6호
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• pp.677-684
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• 2005

A phased array antenna was fabricated using four-element ferroelectric phase shifters with a coplanar waveguide (CPW) transmission line structure based on a $Ba_{0.6}Sr_{0.4}TiO_3(BST)/MgO$ structure. Epitaxial BST films were deposited on MgO (001) substrates by pulsed laser deposition. To attain the large differential phase shift and small losses for a ferroelectric CPW phase shifter, an impedance-matching-part adding technique between the effective transmission line and connecting cable was used. The return loss and insertion loss for this techniqueadapted BST CPW device were improved with respect to those for a normal BST CPW device. For an X-band phased array antenna system consisting of ferroelectric BST CPW phase shifters, power divider, dc block, patch antenna, and programmed dc power, the steering beam could be tilted by $15^{\circ}$ in either direction.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1990년도 봄 학술발표회 논문집
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• pp.18-23
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• 1990

The paper is concerned with the elasto-plastic and geometrically nonlinear analysis of shell structures using an improved degenerated shell element. In the formulation of the improved degenerated shell element, an enhanced interpolation of transverse shear strains in the natural coordinate system is used to overcome the shear locking problems; the reduced integration technique in in-plane strains is applied to avoid membrane locking behavior; selective addition the nonconforming displacement modes improve the element performances. This element is free of serious locking problems and undesirable compatible or commutable spurious kinematic deformation modes and passes the patch tests. An incremental total Lagrangian formulation is presented which allows the calculation of arbitrarily large displacements and rotations. The resulting nonlinear equations are solved by the Newton-Raphson solution scheme. The versatility and accuracy of this improved degenerated shell element are demonstrated by solving several numerical examples.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.28-30
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• 2002

The PD in GIS leads to a charge transfer and a voltage drop across the discharge area. They cannot be measure directly but we can measure electromagnetic wave made by PD. In generally, compared with VHF band, electromagnetic waves of UHF band have a low noise therefore, we can detect the real defect with several pC in GIS using UHF method. In this paper, the U-slot microstrip patch antenna for measuring PD signal in GIS is presented. the proposed UHF sensor are designed to have large band characteristics and unaffected structure for GIS operation.

• Journal of Chest Surgery
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• 제21권4호
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• pp.748-756
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• 1988

Transaortic closure of ventricular septal defect, suturing a patch on the morphological right ventricular side in patients with congenitally corrected transposition of great arteries might help to avoid postoperative complete heart block if the aorta is large and the subaortic conus is not well developed. In two patients[aged 6 and 16 years] with congenitally corrected transposition of great arteries, ventricular septal defect, and pulmonary stenosis, transaortic closure of ventricular septal defect was performed. No postoperative complete heart block resulted. One hospital death occurred because of sepsis who had underwent reoperation due to bleeding from the aortotomy site. Minimal aortic regurgitation developed in another patient.

• Journal of Chest Surgery
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• 제28권7호
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• pp.713-716
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• 1995

A 75-year-old man was admitted to the hospital because of a pericardial effusion.After 3 L of blood-stained pericardial fluid was drained, clinical examination together with echocardiography and chest computed tomography showed a tumor in the right atrium. At operation a pedunculated vascular tumor was found with a broad base which was embedded in the atrial wall and extended into the pericardium.A wide resection was performed resulting in a large defect of the right atrial wall. The defect was reconstructed with a pericardial patch. The patient did well postoperatively, but bloody pleural effusion developed later, presumably because of pulmonary metastasis. The patient died 2 months after surgery as a result of respiratory failure.

• Journal of Chest Surgery
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• 제32권12호
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• pp.1119-1122
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• 1999

Native valve endocarditis (NVE) without preexisting structural valve or congenital cardiac malformation especially in pediatric group is rare. A case of isolated tricuspid valve endocarditis in a 7-year-old child without any cardiac malformation is described. This child had suffered from fever and productive cough for 3 weeks. Blood culture grew Staphylococcus aureus. Fever was not controlled even with proper antibiotic treatment. Transthoracic echocardiogram and lung perfusion scan revealed a large vegetation on the tricuspid valve with multiple embolism Surgical procedures included vegetectomy partial cusps resection and pericardial patch valvuloplasty. Th patient was in NYHA class I during follow up.

• Journal of Chest Surgery
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• 제25권7호
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• pp.736-738
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• 1992

We report the successful use of Nifedipine in the treatment of acute pulmonary hypertension in an young child after a cardiac operation. This patient had undergone patch closure of large ventricular septal defect. She had signs of severe pulmonary artery hypertension unresponsive to hyperventilation, oxygenation, sedation, and a myriad of vas-oactive drugs. Nifedipine, 0.3mg /kg every 4 hours, effectively treated her pulmonary artery hypertension and allowed for a smooth postoperative course and positive outcome. The drug lowered systemic diastolic pressure, but not systolic pressure.

• Journal of Chest Surgery
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• 제45권5호
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• pp.348-350
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• 2012

We herein report a very rare case of adult right-sided Bochdalek hernia accompanied with hepatic hypoplasia and inguinal hernia. A 29-year-old man was admitted with right-sided pneumothorax. A computed tomography was performed and revealed large right sided Bochdalek hernia with hepatic hypoplasia. Under thoracolaparotomy, the defect was closed with Gore-Tex soft tissue patch. After the operation, left-sided inguinal hernia was found. However, it turned out that it had been present during infancy and spontaneously resolved during adolescence. This is the first report of right-sided Bochdalek hernia with hepatic hypoplasia and inguinal hernia in an adult.

• Animal Systematics, Evolution and Diversity
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• 제34권4호
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• pp.190-193
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• 2018

Three species of Acrolepiopsis: A. issikiella (Moriuti, 1961), A. japonica Gaedike, 1982, and A. postomacula (Matsumura, 1931), are recorded from Korea for the first time. Acrolepiopsis issikiella is characterized by having the white costal strigulae and a large dorsal patch on the forewing. Acrolepidopsis japonica is the smallest congener in Korea. Acrolepiopsis postomacula is the only Korean species of Acrolepiinae associated with Hosta. Distributions and larval biology of the three species are summarized. Two species, A. issikiella and A. japonica, are potential pest species of yam-cultivating farms in Korea. Superficial and genital features of the species, if available, are illustrated.

• Structural Engineering and Mechanics
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• 제5권2호
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• pp.137-148
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• 1997

In computing eigenvalues for a large finite element system it has been observed that the eigenvalue extractors produce eigenvectors that are in some sense more accurate than their corresponding eigenvalues. From this observation the paper uses a patch type technique based on the eigenvector for one mesh quality to provide an eigenvalue error indicator. Tests show this indicator to be both accurate and reliable. This technique was first observed by Stephen and Steven for an error estimation for buckling and natural frequency of beams and two dimensional in-plane and out-of-plane structures. This paper produces and error indicator for the more difficult problem of three dimensional brick elements.