• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.4 no.2
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• pp.20-28
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• 2008

According to IAEA regulations, a transportation package of radioactive material should perform its intended function of containing the radioactive contents after the drop test, which is one of hypothetical accident conditions. Impact limiters attached to a transport cask absorb the most of impact energy. So, it is appreciated to determine properly the shape, size and material of impact limiters. A material data needed in this determination is a dynamic one. In this study, several materials considered as those of impact limiters were tested by a drop weight facility to acquire dynamic material characteristics data. Impact absorbing volume of the impact limiter was derived mathematically for each drop condition. A size optimization of impact limiter was conducted. The derived impact absorbing volumes were applied as constraints. These volumes should be less than critical volumes generated based on the dynamic material characteristics. The derived procedure to decide the shape of impact limiter can be useful at the preliminary design stage when the transportation package's outline is roughly determined and applied as input value.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1991.10a
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• pp.10-11
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• 1991

In this paper, Arachidic Acid of long-chain fatty acid was soluted by chloroform and observed $\pi$-A curve in trough. In our experimental result, optimum pressure for fabricating the LB film was 30mN/m. In $\pi$-A curve measurment, temperature dependence was investigated between 20-50($^{\circ}C$). However, in this temperature range, the variation of solid phase pressure was not observed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1991.10a
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• pp.73-78
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• 1991

In this study of stacked type film chip capacitor, the important parameters are heat-treated temperature, pressure and time. We measured the temperature dependence of dielectric properties and dissipation factor and the frequency dependence of dielectric properties, dissipation factor, ESR(Equivalent Series Resistance) and impedance in stacked type film capacitor. As a result, the best conditions of heat-treated temperature, pressure and time were proved to be 130$^{\circ}C$, 10kg/$\textrm{cm}^2$ and 3hrs, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.12
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• pp.987-993
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• 2001

In this paper, we presents the construction details and output characteristics of a thick film piezoresistive strain gage. The thick film was printed on the ceramic diaphragm back side by screen printing and cured at 850$^{\circ}C$. The strain distribution and deflection on ceramic diaphragm were performed with finite-element method(FEM tool ANSYS-5.3). Various thick film strain gage characteristics were analysed, including nonlinearity, hysteresis, stability and sensitivity of thick film strain gages.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.532-534
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• 2000

Si thin films on p-type (100) Si substrate have been fabricated by pulsed laser deposition technique using a Nd:YAG laser. The pressure of the environmental gas during deposition was varied from 1 to 3 Torr. After deposition, Si thin film has been annealed again at nitrogen ambient. Strong violet-indigo photoluminescence have been observed from Si thin film annealed in nitrogen ambient gas. As increasing environmental gas pressure, weak green and red emissions from annealed Si thin films also observed by photoluminescence.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05a
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• pp.68-72
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• 2002

Power steering of a car plays a role that reduce driver's handle control power. Lately, it is operated using oil pressure by most engine power. However, it is tendency that electrically power steering (EPS) is used recently instead of oil pressure type more for environmental and economical reason. In this paper is SRM designed and analyzed for EPS application.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1668-1671
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• 2005

Vulcanized natural rubber was pulverized using a single screw extruder in a non-cryogenic Solid Shear Extrusion process where rubber granulates were subjected to high compressive and shear stresses. The producted particles had diameters ranging from 40 to 1200$\{mu}m$. A principle used in this paper was developed in Russia. The development method for producing a polymeric material powder consists in compressing said material by shearing the material during a pressure increase and cooling. Consecutive breakdown is carried out by shearing the material during the pressure decrease and cooling.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.476-479
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• 1997

A Knowledge of friction force in pneumatic cylinders makes it possible to improve cylinder description during simulation and to asses performance under changing operating conditions more accurately. Such knowledge is particularly useful, for example, when modeling continuous pneumatic positioning systems or predicting the operating conditions under which stick slip may occur, as well as in establishing preventive maintenance procedures for pneumatic cylinders. Friction force depends on a number of factors, including operating pressure, seal running speed on the cylinder barrel and rod, barrel material and surface roughness, seal dimensions and profile, seal material, lubrication conditions, cylinder distortion during assembly, and the operating temperature of cylinder components. This paper shows a system for measuring the friction force caused by a seal used in pneumatic cylinders. Results of experimental tests show that seal friction forces for grease lubricated service are clearly dependent on speed and pressure and are les sensitivity to other parameter. i.e., barrel material and roughness, seal material, and profile.

• Journal of Mechanical Science and Technology
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• v.14 no.5
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• pp.553-561
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• 2000

This paper presents a numerical model of multi phase flow of the mixtures of molten material-liquid-vapor, particularly in thermal nonequilibrium. It is a two-dimensional, transient, three-fluid model in Eulerian coordinates. The equations are solved numerically using the finite difference method that implicitly couples the rates of phase changes, momentum, and energy exchange to determine the pressure, density, and velocity fields. To examine the model's ability to predict an experimental data, calculations have been performed for tests of pouring hot particles and molten material into a water pool. The predictions show good agreement with the experimental data. It appears, however, that the interfacial heat transfer and breakup of molten material need improved models that can be applied to such high temperature, high pressure, multi phase flow conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.05a
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• pp.55-58
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• 1996

A new type CuN/Cu/CuN thin film electrode material with high adhesion to glass was developed by the dc reactive planar magnetron sputtering system for the PDP(Plasma Display Panel). The adhesive force of the CuxN thin film was in the range of 20∼40(N) under the conditions of the N$_2$ partial pressure of 15%, discharge current of 70mA, discharge voltage of 450v and substrate bias voltage of -100V. The adhesive force was depended on the N$_2$ partial Pressure, discharge current and substrate bias voltage.