• Title/Summary/Keyword: Gas release

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SAMI Galaxy Survey Data Release 2: Absorption-line Physics

  • Oh, Sree;Scott, Nicholas;van de Sande, Jesse
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.2
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    • pp.53.1-53.1
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    • 2018
  • We present the second data release from the SAMI Galaxy Survey. The data release contains reduced spectral cubes for 1559 galaxies, about 50% of the full survey, having a redshift range 0.004 < z < 0.113 and a large stellar mass range 7.5 < log($M_*/M_{\odot}$) < 11.6. This release also includes stellar kinematic and stellar population value-added products derived from absorption line measurements, and all emission line value-added products from Data Release One. The data are provided online through Australian Astronomical Optics' Data Central. Our poster presents stellar/gas kinematics on the metallicity-mass plane and highlight several galaxies from the SAMI Galaxy Survey that have interesting stellar and gas kinematics. For more information about data release 2, please see: https://sami-survey.org/abdr.

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Analysis of Gas Flow Behavior with Experiments for LPG releasing and 3D Mapping of Gas Sensor (LPG 누출 및 가스센서 3D Mapping을 통한 가스유동현상 분석)

  • Kim, Jeong Hwan;Lee, Min-Kyung;Kil, Seong-Hee;Lee, Jin-han;Jo, Young-do;Moon, Jong-Sam
    • Journal of the Korean Institute of Gas
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    • v.21 no.5
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    • pp.45-55
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    • 2017
  • Release and fire/explosion tests of flammable gas are extremely dangerous. Furthermore, it is difficult to select the site where the experiment can be performed. In these reasons, gas flow analysis(CFD) has been used as much as possible. However, with the opening of the Energy Safety Empirical Research Center in Yeongwol-gun, Gangwon-do in October 2016, it was possible to conduct releases and detection tests of small scale combustible gas as well as large scale / high pressure / ultra low temperature experiments. In this study, LPG leaked after the calibration and placement of the sensor, the sensor detected LPG and the data were visualized as a contour map. And the differences between the actual release(28s, max 3.7[m]) and the analysis were analyzed compared to the FLACS analyzed under the same conditions.

Sterilization Test of Microorganisms of Slow-released ClO2 Gas Gel-Pack (서방출형 이산화염소 가스 젤팩의 미생물 살균 시험)

  • Lee, Kyung-Haeng;Kim, Hong-Gil
    • The Korean Journal of Food And Nutrition
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    • v.31 no.2
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    • pp.308-312
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    • 2018
  • Even though chlorine dioxide ($ClO_2$) is utilized in a pre-treatment due to its effective sterilizing activity for microorganisms and its safety for food, it has a limitation in maintaining freshness of the food product. In this study, a low-concentration $ClO_2$ gas was produced in a packaging form of air-permeable gel pack so that it could be released continuously over several days. The amount of $ClO_2$ gas emission and microbial inactivation effect against foodborne pathogens were measured during the release of $ClO_2$ gas. As a result of measuring the change of color in order to confirm whether the chlorine dioxide gas was eluted in the form of a sustained release, the yellowness was significantly higher at higher gel pack concentration and higher value during storage periods. The slow-released $ClO_2$ gel-pack showed clear inactivation effect against Escherichia coli and Staphylococcus aureus with 99.9% inactivation efficiency. As a result of measuring the sterilization effect of Listeria monocytogenes by the concentration of chlorine dioxide gas, the sterilization effect was increased as the concentration was increased. Therefore, the slow-released $ClO_2$ gel-pack is feasible to apply for industry usages.

Assessment of Gas Release Dispersion and Explosion in Pipeline (파이프라인에서의 가스누출 확산과 폭발 영향평가)

  • Jung In-Gu;Yoo Sang-Bin;Lee Su-Kyung;Kim Lae-Hyun
    • Journal of the Korean Institute of Gas
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    • v.2 no.2
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    • pp.61-69
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    • 1998
  • The risk assessments for gas leak in underground pipeline are conducted about the explosion accident of AHYUN-DONG underground service-base on December, 1994(Gaussian gas, LNG) and the accident of TAEGU subway on April 1995(Heavy gas LPG). We have calculated the total mass of gas release and have respected the efficient of explosions with report of the spot. The dispersion zones of LNG were calculated as large as fifteen times to those of LPG by ALOHA. The effects of thermal radiation from LNG explosion were assumed less than that from LPG by PHAST.

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Consequence Analysis for Release Scenario of Buried High Pressure Natural Gas Pipeline (지하매설 도시가스배관의 누출시나리오에 따른 사고피해영향분석)

  • Kim, Jin Hyung;Ko, Byung Seok;Yang, Jae Mo;Ko, Sang-Wook;Ko, Jae Wook
    • Journal of the Korean Institute of Gas
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    • v.18 no.3
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    • pp.67-74
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    • 2014
  • Buried natural gas pipelines in densely populated urban areas have serious hazards of property damages and casualties generated by release, dispersion, fire and explosion of gas caused by outside or inside failures. So as to prevent any accident in advance, managers implement danger management based on quantitative risk analysis. In order to evaluate quantitative risk about buried natural gas pipelines, we need calculation for radiant heat and pressure wave caused by calculation for release rate of chemical material, dispersion analysis, fire or explosion modeling through consequence analysis in priority, in this paper, we carry out calculation for release rate of pressured natural gas, radiant heat of fireball based in accident scenario of actual "San Bruno" buried high pressured pipelines through models which CCPS, TNO provide and compare with an actual damage result.

On the Application of CFD Codes for Natural Gas Dispersion and Explosion in Gas Fuelled Ship

  • Kim, Ki-Pyoung;Kang, Ho-Keun;Choung, Choung-Ho;Park, Jae-Hong
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.7
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    • pp.946-956
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    • 2011
  • The main objectives of this study are to analyze the leaked gas dispersion and quantify the potential overpressures due to vapor cloud explosions in order to identify the most significant contributors to risk by using Computational Fluid Dynamics (CFX & FLACS) for gas fuelled ships. A series of CFD simulations and analyses have been performed for the various gas release scenarios in a closed module, covering different release rates and ventilating methods. This study is specially focused on the LNG FGS (Fuel Gas Supply) system recently developed for the propulsion of VLCC crude oil carriers by shipyards. Most of work presented is discussed on the gas dispersion from leaks in the FGS room, and shows some blast prediction validation examples.

Simulation of Pore Interlinkage in the Rim Region of High Burnup $UO_2$Fuel

  • Koo, Yang-Hyun;Oh, Je-Yong;Lee, Byung-Ho;Cheon, Jin-Sik;Joo, Hyung-Koo;Sohn, Dong-Seong
    • Nuclear Engineering and Technology
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    • v.35 no.1
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    • pp.55-63
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    • 2003
  • Threshold porosity above which fission gas release channels would be formed in the rim egion of high burnup UO$_2$ fuel was estimated by the Monte Carlo method and Hoshen-Kopelman algorithm. With the assumption that both rim pore and rim grain can be represented by cube, pore distribution in the rim was simulated 3-dimensionally by the Monte Carlo method according to porosity and pore size distribution. Then, using the Hoshen-Kopelman algorithm, the fraction of open rim pores interlinked to the outer surface of a fuel pellet was derived as a function of rim porosity. The simulation showed that porosity of 24-25% is the threshold above which the number of rim pores forming release channels increases very rapidly. On the other hand, channels would not be formed if the porosity is less than about 23.5%. This is consistent with the observation that, for porosity less than 23.5%, almost no fission gas is released in the rim. However, once the rim porosity reaches beyond 25%, extensive open paths would be developed and considerable fission gas release would start in the rim.

Development and Selection of Accident Scenarios for Risk Assessment in HF Charging Process (HF 충진 공정의 위험성 평가를 위한 가상사고 시나리오 발굴 및 선정)

  • Jang, Chang-Bong
    • Journal of the Korean Institute of Gas
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    • v.17 no.4
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    • pp.26-32
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    • 2013
  • The best way to prevent major occupational accidents is prohibiting use of hazardous substances such as flammable gas, toxic gas whereas using alternative substances that ensured safety. but if there are no economic efficiency and substituting technologies of alternative substances, the best way is preparing to prevent accidents thoroughly. Therefore, this study has developed and selected release scenarios to use and apply for consequence analysis and emergency action plan for HF charging process of chemical plants that have HF release accidents and high probability of release accidents.

4-stroke 디젤엔진의 성능예측에 관한 연구

  • 오태식;오세종;양재신
    • Journal of the korean Society of Automotive Engineers
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    • v.4 no.2
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    • pp.58-68
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    • 1982
  • It is well known to diesel engineers that the heat release pattern is one of the most important factors affecting engine performance. Thorough research in heat release pattern has materially helped the progress in high-speed diesel engine development . This paper is based on the research conducted at KAIST and Daewoo Heavy Industry last year. The purpose of this paper is to determine the heat release pattern in combustion chamber of MAN M type, the famous low-noise engine. Thermodynamic cycle simulation was performed using Whitehous-Way's heat release pattern with modified coefficients and Annand's heat transfer model. Instantaneous temperature and pressure of gas in cylinder could be determined by the numerical solution of simultaneous equation of mass conservation, equation of energy conservation, and state equation of ideal gas. Calculated results were compared with measured values in some details emphasizing upon the factors affecting rate of heat release. The agreement was fairly good and revealed why M type should have lower burning velocity at the early part of combustion in spite of high injection rate. Additional results by parametric studies were given in relation to fuel injection conditions for further application to engine development.

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Oxidation Kinetics of $UO_2$ Pellets in Defective Fuel Rods and Its Effect on Fission Gas Release (노내 손상 핵연료의 산화거동 및 핵연료 산화가 핵분열기체 방출에 미치는 효과)

  • Koo, Yang-Hyun;Sohn, Dong-Seong;Yoon, Young-Ku
    • Nuclear Engineering and Technology
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    • v.26 no.1
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    • pp.90-99
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    • 1994
  • One of the major phenomena occurring in defective fuel rods is the oxidation of UO$_2$ fuel pellets from UO$_2$ to UO$_{2+}$x/ by the oxygen Produced from the dissociation of the steam in the Pellet-to-clad gap, which leads to the enhancement of fission gas release. In this paper, the oxidation kinetics of defective fuel rods was analyzed on the basis of operating conditions of the reactor and defective fuel rod itself. Oxidation kinetics of the fuel pellet was determined under the assumption that the gap is filled with the saturated steam of 150 atm and an enhancement factor for fission gas release was introduced to take into account the effect of fuel oxidation on fission gas release. Comparison with experimental data shows that the enhancement factor predicts well the increased fission gas release due to the oxidation of UO$_2$fuel pellets.

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