• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.5
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• pp.235-241
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• 2018

The internal pressure is a critical parameter for designing a pressure vessel. The static pressure that a pressure vessel must withstand is usually determined according to the various codes and standards with simple formula or numerical simulations considering the geometric parameters such as diameter and thickness of a vessel. However, there is no specific codes or technical standards we can use practically for designing of pressure vessels which have to endure the detonation pressure. Detonation pressure is a kind of dynamic pressure which causes an impulsive pressure on the vessel wall in a extremely short time duration. In addition, it is known that the magnitude of reflected pressure at the vessel wall due to the explosion can be over twice the incident pressure. Therefore, if we only consider the reflected pressure, the design of the pressure vessel can be too conservative from the economical point of view. In this study, we suggest a practical method to evaluate the magnitude of maximum allowable pressure that the pressure vessel can withstand against the detonation inside a vessel. As an example to validate the proposed method, we consider the pressure vessel containing hydrogen gas.

• Journal of the Korean Geosynthetics Society
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• v.13 no.3
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• pp.39-47
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• 2014

In this study, the full scale model tests were performed with track-roadbed system such as Ho-nam high speed railway. The measured data gives good similar a roadbed pressure with equivalent depth to the Odemark's theory. In the case of earth pressures have a under 50 kPa at upper-subgrade applying 330 kN static loading. Results of cyclic loading tests did not differ significantly from those of static loading test. The elastic displacement at HSB layer has a level of 1/100 compared to the 1 mm that it was evaluation criteria for speed up of High Speed Railway. Elastic displacement at subgrade layer was measured a level of 1/175. The dynamic characteristics of track-roadbed with loading frequency level were linearly increased under 35 Hz, while the wheel loading, displacement and acceleration of roadbed were decreased loading frequency above 35 Hz.

• Radiation Oncology Journal
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• v.8 no.1
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• pp.7-15
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• 1990

The ultimate objective of our experiment is to obtain the precise distribution of temperature in malignant tumors occurring in cerebral parenchyme of human beings when we will carry out interstitial hyperthermia in the near future. To achieve this purpose, first of all, it is necessary to make an attempt at performing interstitial hyperthermia in vivo under the similar condition of human beings. Therefore, we chose cats as materials much alike tissue characteristics of human beings. Moreover, it is also necessary to get the basic data from dynamic phantom in order to standardize and compare results obtained from interstitial hyperthermia carried out in cats. By having performed these experiments we got the following results. 1) On doing interstitial hyperthermia with 915 MHz microwave, the possible treated volume was 2 cm by 2 cm by 6 cm according to $50\%$ specific absorption rate (SAR). 2) The distribution of temperature within non-circulated static phantom was much the same as power density in air, but we observed that the temperature, within $5\~10$ minutes, rose to more higher than $55^{\circ}C$ not measured with Ga-As fiberoptic thermistor which was not impeded by microwave after performing interstitial hyperthermia. 3) Within dynamic phantom in which normal saline was circulating, temperature reached steady state which was maintained for more than 45 minutes through transit period in 5 minutes after starting interstitial hyperthermia. 4) When we interrupted circulation in the dynamic phantom, we observed that temperature rose to the same level as in the static phantom. 5) We could carry out interstitial hyperthermia safely when we used the generating power below 5 watts. Abrupt interruption of circulation caused a rapid increase in temperature. Times taking to rise to maximum $55^{\circ}C$ were 15.2 minutes (SE 0.4),9.7 minutes (SE 0.3), and 6.3 min-utes (SE 0.4) respectively with generating powers of 5,10, and 15 watts.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.166-172
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• 2016

This paper deals with the seismic qualification of the reflective metal insulation for thermal shielding that is installed on the outer surfaces of the main equipment of the primary coolant system of a nuclear power plant. A small-scale model of the reactor pressure vessel, which has equivalent dynamic characteristics, was designed to be tested in domestic seismic testing facilities in the future. In this study, seismic analysis of the small-scale model installed with metal insulation was performed using equivalent static analysis and response spectrum analysis. The required Response Spectrum for main equipment of the primary coolant system of APR-1400 plant were considered to establish the enveloping response spectrum, which was applied to the seismic analysis model. The results from two seismic analysis methods were compared to show the structural adequacy of the metal insulator design against a safe shutdown earthquake. This study will form the basis for the seismic testing to support the seismic qualification of the reflective metal insulator.