• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.772-774
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• 2007

The improvement in the field emission parameters, luminescent uniformity, degradation rate and half life has been observed for the thin-multi wall carbon nanotube (t-MWCNT) composite, after incorporating the Zn nanoparticles. The Zn nanoparticles $(diameter\;{\sim}\;100\;{\pm}15\;nm)$ has been incorporated to synthesize the Zn-t-MWCNT composite.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.55-58
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• 2004

Phenolin resin, prepared form phenol and formaldehyde, is one of the oldest thermosetting resins available. Phenolic resins are cured via condensation polymerization with evolution of water, which in molding process is a big problem. The use of phenolic resins in glass fiber composites is growing, primarily due to their low flame spread, low smoke generation and low smoke toxicity properties. SMC of phenolics has been rearched since the 1986. The technology challenge was to match resin viscosity, handling and cure with those for the polyester SMC to avoid any special processing for fabricators and end users. Phenolic SMC was chosen because of the ease of molding to the required shape with light- weight, thin wall structure and with excellent fire protection.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.6
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• pp.923-926
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• 2017

In this study, a novel wideband conformal thin antenna is presented for endoscopic capsule application at the 915 MHz Industrial, Scientific and Medical (ISM) band. The thickness of the antenna is only 0.2 mm which can be wrapped inside a capsule's inner wall. By cutting meandered slots on patch, open end slots on ground and utilizing long arm, the proposed antenna can obtain significant size reduction. The net volume of the proposed antenna including substrate and superstrate is only $37.4mm^3$ ($187mm^2$ surface area). This conformal antenna has shown good performance through simulation and measurement with maximum gain of -23 dBi and wide bandwidth from 137 MHz - 205 MHz depending on different environment. In addition, the effect of internal materials specially metallic battery is discussed briefly.

• Electrical & Electronic Materials
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• v.10 no.6
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• pp.548-554
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• 1997

We fabricated the sample of ultra thin lipid membrane(L-$\alpha$-DLPC) by LB method. The $\pi$-A isotherm of the DLPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. For the good property of lipid monolayer film, it was necessary to prepare at the lower speed of compressing, with an appropriate volume of solutions for spreading. Absorption, transmitance and intensity with the UV spectrophotometer were measured. The Z-type multilayers showed good characteristics better than Y-type. So we found building-up of structurally high quality LB films is essential to study properties of the films and to get reproducible data.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.848-851
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• 2003

Display devices are becoming increasingly important as an interface between humans and machines in the growing information society In display device, PDP(Plasma Display Panel) has many advantages in that wide screen, light weight, thin, wide viewing angle and unaffected by magnetic field. In this paper, modified ramp waveform is suggested by Vt Close Curve, and PDP driving circuit is designed by modified ramp waveform, this modified ramp waveform have more addressing wall voltage better then the old ramp waveform.

• Journal of Chest Surgery
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• v.22 no.3
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• pp.468-472
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• 1989

Bronchogenic cysts are uncommon congenital lesions which are derived from primitive foregut. Most of the bronchogenic cysts may occur at the tracheal bifurcation, both main bronchi, the lung parenchyme and the mediastinum. We experienced a case of bronchogenic cyst with a esophageal stalk. The diagnosis was made by simple chest x-ray and confirmed by bronchoscopy and chest CT. On the chest CT findings, 6.8X4.8 cm-sized oval shaped mass was located on the right posteroinferior side of the carina, elevating the right main bronchus and the thin wall of the mass was enhanced with contrast materials. On the operative findings, the esophagus and the cyst were connected with a stalk and the cyst was filled with mucinous materials. And on the histological findings, the mass was lined with pseudostratified ciliated columnar epithelium. Thus we report this case of bronchogenic cyst with review of literatures.

• Korean Journal of Veterinary Research
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• v.23 no.1
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• pp.119-122
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• 1983

Paravertebral anesthesia for operation of abdominal wall in Korean cattle were effectively accomplished with the following technique. Any problems in surgical procedure were not observed under the block of ventral branches of the last thoracic nerve and the first and second lumbar nerves with the administration of preanesthetic. The site of injection for blocking of ventral branches of the thirteenth thoracic nerve were approximately 5cm lateral to the midline from the posterior edge of spinous process of the 13th thoracic vertebra and about 10ml of local anesthetic was injected immediately anterior to the transverse process of the first lumbar vertebra through thin site. The block of ventral branches of the first and second lumbar nerves were obtained by injecting 10ml of local anesthetic immediately below the posterior edge of transverse process of the 2nd and 4th lumbar vertebra, respectively.

• 한국가시화정보학회:학술대회논문집
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• 2002.11a
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• pp.117-120
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• 2002

An experimental research has been carried out for flow control of the shock wave/turbulent boundary-layer interaction utilizing aeroelastic mesoflaps. Various shapes and thicknesses of the mesoflap are tested to achieve different deflections of the flap, and ail the results are compared to the solid-wall reference case without flow-control mechanism. Quantitative variation of skin friction has been measured downstream of the interactions using the laser interferometer skin friction meter, and qualitative skin friction distribution has been obtained by observing the interference fringe pattern on the oil-film surface. A strong spanwise variation in the fringe patterns with a narrow region of separation near the centerline is noticed to form behind the shock structure, which phenomenon is presumed partially related to three-dimensional flow structures associated with both the sidewalls and the bottom test surface. The effect of the shape of the cavity is also observed and it is noticed that the shape of the cavity is not negligible.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.3
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• pp.389-396
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• 2001

Direct numerical simulation of bubble growth and merger process on a single nucleation site during partial nucleate boiling is performed. The equations governing conservation of mass, momentum and energy are solved using a finite difference method combined with a level set method for capturing the vapor-liquid interface. The level set method is modified to include the effects of phase change at the interface and contact angle at the wall. Also, a simplified formulation for predicting the evaporative heat flux in a thin liquid micro-layer is developed and incorporated into the level set formulation. Based on the numerical results, the bubble growth and merger pattern and its effect on the heat transfer are discussed.

• Structural Engineering and Mechanics
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• v.19 no.2
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• pp.217-230
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• 2005

A steel silo traditionally consists of a cylindrical and a conical shell. In order to facilitate emptying operations, the cylinder is placed on local supports. This may lead to dangerous stress concentrations and eventually to local instability of the cylindrical wall. In this contribution, the locally supported cylinder is strengthened by means of ring stiffeners and longitudinal stiffeners and the effect of their dimensions on the buckling stress is investigated. This study leads to a number of diagrams, each of them representing the effect of one of the dimensions on the buckling stress. In each diagram, the failure pattern corresponding to the buckling stress is indicated.