• Journal of Multimedia Information System
• /
• v.9 no.3
• /
• pp.219-226
• /
• 2022

The advancement of realistic visual effects technology provides increasingly immersive experiences and consumer satisfaction with content. The explosion and destruction effects in live-action films and animations are some of the most frequently used visual effects, but they are relatively difficult to execute, so it is challenging to make them look realistic. This study tested a method of effectively realizing computer-generated explosions and destruction. Experiments for this study are as follows: first, the interlink according to density accumulation of the fluid; second, the interlink according to the temperature accumulation of the fluid; and third, the interlink according to the distance between the fluid and the involved objects. This study was conducted to identify an optimal solution for producing computer-generated explosions and destruction.

• Journal of the Korean Society of Safety
• /
• v.38 no.2
• /
• pp.30-35
• /
• 2023

Acetone is a widely used Volatile Organic Compound (VOC) in industries and laboratories. However, acetone affects human health adversely and causes fires and explosions. Early acetone detection and improved personnel training in safety and emergency management are necessary to prevent acetone-related accidents. The multi-VOC acetone detectors used currently have a sensitivity and selectivity limit. In this study, we discovered that Pt-loaded iron oxide (a metal oxide semiconductor) conversely, has high detection and selectivity for very low-levels of acetone gas. The loaded Pt catalyzes the reaction between the sensing materials' surface and the oxygen molecules in the air; this optimizes acetone detection and can decrease acetone-related illnesses, fires and explosions.

• Journal of Korean Association for Spatial Structures
• /
• v.15 no.3
• /
• pp.21-26
• /
• 2015

• Proceedings of the Korean Nuclear Society Conference
• /
• 2002.05a
• /
• pp.190.1-190
• /
• 2002

• Proceedings of the Korean Nuclear Society Conference
• /
• 2004.05a
• /
• pp.171.2-171.2
• /
• 2004

• Proceedings of the Korean Nuclear Society Conference
• /
• 2002.10a
• /
• pp.183-183
• /
• 2002

• Journal of the Korean Institute of Gas
• /
• v.20 no.5
• /
• pp.89-95
• /
• 2016

Keeping the gas pipelines in the common utility tunnel is useful because it has a lower risk of corrosion than conventional burial, and can prevent from excavating construction. But, explosions in common utility tunnels can cause greater damage from the blast overpressure compared to outdoor explosions, due to nature of the confined environment. Despite this fact, however, research on common utility tunnels has been limited to fire hazard and little has been studied on the dangers of explosions. This study developed scenarios of methane gas explosion caused by gas leak from gas piping within the common utility tunnel followed by unknown ignition; the study then calculated the extent of the impact of the explosion on the facilities above, and suggested the needs for designing additional safety measures. Two scenarios were selected per operating condition of safety devices and the consequence analysis was carried out with FLACS, one of the CFD tools for explosion simulation. The overpressures for all scenarios are substantial enough to completely destroy most of the buildings. In addition, we have provided additional measures to secure safety especially reducing incident frequency.

• The Journal of Engineering Geology
• /
• v.7 no.1
• /
• pp.63-79
• /
• 1997

In this study, our purpose is to develop a technique to discriminate artificial explosions from local microearthquakes on the basis of time-frequency domain. To obtain spectral features of artificial explosions and microearthquakes, we used 3-d spectrograms(frequency, time and amplitude) because this is a useful tool to study the frequency content of entire seismic waveforms observed at local and regional distances (e. g., Kim et al., 1994). P and S waves from quarry blasts show that frequency content of dominant amplitude appeared above 10 Hz and Rg phases that are observed at near distance ranges. But P and S waves from microearthquakes have more broad frequency content as well as below 10 Hz. And for discrimination, Pg/Lg spectral ratio is performed below 10 Hz. In order to select time windows we computed group velocity using multiple filter method(MFM) and removed free surface effects from all 3-components data for improving on data quality. Next step, we computed Fast-Fourier transform, and a log average spectral amplitude over seven frequency bands : 0.5 to 3, 2 to 4, 3 to 5, 4 to 6, 5 to 7, 6 to 8 and 8 to 10 Hz. The best separation is observed from 6 to 8 Hz.

• The Korean Journal of Zoology
• /
• v.11 no.3
• /
• pp.85-91
• /
• 1968

Artificial and natural radioactivity in airborne, rain-out and fallout dusts in Seoul district in the period of 1963-1967 were studied by measuring gross-activity and by analyzing nuclides by means of $\\gamma$-spectrometry. Short-lived radium and thorium decay products give rise to most of the airborne activity unless the fission product concentration is extremely high and it is likely to be said activity remaining after a few days is attributable to fission products. Of seven Chinese nuclear explosions performed at Lop Nor, Sinkiang Province, two exhibited the activity of extremely high concentration of fission product and reached Seoul district around 30 hours after the explosion. The activity was followed by a sudden decrease in less than a week, in contrast to the long-lasted activity of low concentration originating from the huge tests performed by the United States and the USSR in 1956-1962. The radioactive environmental contamination in Seoul district, due to the Chiness nuclear test explosions, largely depends on the height above the earth at which the nuclear explosion is performed and the type of nuclear device as well as the weather system at the time and immediately after the explosion, especially the jet stream in middle latitude in the upper troposphere.

• Journal of the Korea Society for Simulation
• /
• v.29 no.2
• /
• pp.119-127
• /
• 2020

This study numerically investigated a structural behavior subjected to consecutive explosions. To this end, a small scale one-way reinforced slab (RC) with fixed-fixed boundary condition was considered as the target structure, and a commercial software, LS-DYNA, was utilized for finite element (FE) analysis. Prior to performing FE analysis, preliminary tests were carried out to verification of a computational model for the one-way RC slab. In the numerical simulation, identical blast loads were consecutively applied to the structure, and cumulative damage assessment were carried out based on its maximum dynamic displacements. As a result of the numerical simulation, it was found that maximum displacements considering permanent deformation due to a prior explosion were almost linearly increased in every explosion until the hazardous damage threshold.