• Title/Summary/Keyword: 열질량법

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Statistical Uncertainty Analysis of Thermal Mass Method for Residual Propellant Estimation (잔여추진제 추정을 위한 열질량법의 통계적 불확실성 분석)

  • Park, Eungsik;Park, BongKyu;Huh, Hwanil
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.12
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    • pp.1116-1123
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    • 2015
  • The lifetime of a geostationary satellite depends on the residual propellant amount and therefore the precise residual propellant gauging is very important for the mitigation of economic loss arised from premature removal of satellite from its orbit, satellites replacement planning, slot management and so on. In this paper, the thermal mass method and its uncertainty are described. The residual propellant analysis of a geostationary satellite is simulated based on the KOREASAT data and the uncertainty of thermal mass method is calculated by using the Monte Carlo method. The results of this study show the importance parameter of estimation residual propellant using the thermal mass method.

대형 콘 칼로리미터의 신뢰성 구축을 위한 발열량 측정 결과 분석

  • Yu, U-Jun;Kim, Chang-Seop;Jeon, Gwang-Hun;Yeom, Mun-Cheon;SaGong, Seong-Ho;Kim, Jeong-Yong;Kim, Seong-Chan;Yu, Hong-Seon
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2013.11a
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    • pp.49-49
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    • 2013
  • 실규모급 화재 실험의 신뢰성 있는 발열량 측정을 위해서 흡입 배관의 직경 1.6 m, 직선길이 26m, 후드 직경 10 m 그리고 흡입용량 $2,000m^3/min$ 이상의 대형 콘 칼로리미터를 구성하여 헵탄의 화재 크기별 연소 실험을 진행하였다. 발열량 측정을 비교 분석하기 위해서 산소 소모 지수법, 질량 소모법, 복사열 그리고 대류열 측정 기법에 따라서 각각의 발열량을 산출하고 크기를 비교하였다. 그 결과 대형 콘 칼로리미터에 의해서 측정한 산소 소모 지수법은 이론 발열량에 해당하는 질량 소모법과 최대 약 2.3 % 정도, 복사열에 의한 발열량 산출법은 12.2 % 정도, 연소면적에 의한 이상적인 발열량과는 최대 30 % 정도, 그리고 대류열만 고려한 경우 약 50 % 정도 차이가 나는 것을 확인하였다.

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Characteristics study of biological materials using pyrolysis-mass spectrometry (열분해 질량분석법을 이용한 생물학 물질의 특성 연구)

  • Choi Sun-Kyung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.7 no.3 s.18
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    • pp.110-121
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    • 2004
  • Pyrolysis-mass spectrometry, incorporating an in situ thermal hydrolysis and methylation(THM) step, has been used to study biological materials for bacteria, toxin and virus. Newly developed pyrolyzer was used to decompose biological materials, and tetramethylammonium hydroxide(TMAH) was used as a methylation reagent. Chemical ionization(CI) using ethanol and ion trap mass spectrometer(ITMS) were used to ionize and analyze of pyrolysis components, respectively. Analytical characteristics of bacteria (including spore), virus and toxin were analyzed. Also acquisition and interpretation of mass spectra as biomarkers for classification/identification of biological material s were explained.

Predictions of Heat and Mass Transfer Rates to a Spray Droplet Experiencing Condensation (응축을 수반하는 분무수적으로의 열 및 질량전달률 예측)

  • 이상균;조종철;신원기;조진호;서정일
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.5
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    • pp.1763-1773
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    • 1991
  • 본 연구에서는 포화수증기와 공기의 혼합기내에서 분무수적으로의 열 및 질량 전달률을 계산하기 위하여 수적의 부분혼합모형과 비혼합모형에 대하여 수적내 과도온 도분포의 해석해를 적용성이 보장되면서도 계산상의 어려움이 수반되지 않는 형태로 구하기 위하여 수적내부의 열전도해석에 있어서 적분법을 적용하였다. 적분법으로 얻어지는 과도온도분포의 해는 유한차의 다항식으로 표시되어 비혼합모형인 경우 각시 간 구간의 경계에서의 온도분포가 연속성을 유지하면서 물성치들의 온도에 대한 종속 성이 쉽게 고려되고 계산도 용이한 형태이다. 본 보에서 제시하는 해석결과의 적용 성을 조사하기 위하여 완전혼합모형을 포함하는 세가지 수적모형들에 대한 계산결과들 로부터 얻어진 시간변화에 따른 수적의 무차원 체적평균온도변동을 유효한 실험결과들 과 비교, 검토하였으며, 부분혼합모형에 대하여 혼합기의 압력, 수적의 초기온도, 혼 합기 속에 포함되어 있는 수증기의 체적분율, 수적의 초기크기, 수적의 초기속도 및 분사각도가 주위혼합기로부터 수적으로 전달되는 열 및 질량전달에 미치는 영향을 조] 사하고 도출된 대표적인 검토 결과를 제시하였다.

Characteristics study II of biological materials using pyrolysis-mass spectrometry (열분해 질량분석법을 이용한 생물학 물질의 특성 연구(II))

  • Choi, Sun-Kyung;Park, Young-Kyu;Park, Byeng-Hwang
    • Journal of the Korea Institute of Military Science and Technology
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    • v.8 no.3 s.22
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    • pp.83-91
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    • 2005
  • Pyrolysis-mass spectrometry has been used to characterize the 17 biological materials including bacteria and proteins. In this study, an in situ thermal-hydrolysis methylation(THM) procedure using tetramethylammonium hydroxide(TMAH) was employed. The biological materials are ionized using chemical ionization(CI) method with ethanol by ion trap mass spectrometer(ITMS), which attached with our own made pyrolyzer module, and then their pyrolysis mass spectra were obtained. The major distinct characteristic peaks were selected from all the range of mass spectra, and analyzed using principal component analysis(PCA) method to assess the classification/identification possibility of biological materials.

Separation and Identification of Polycyclic Aromatic Compounds in Pyrolysis Products of Cellulose and Lignin (셀룰로오스와 리그닌의 열분해 생성물중의 여러고리 방향족화합물의 분리와 동정)

  • Park, Nae-Joung;Lee, Milton L.
    • Journal of the Korean Chemical Society
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    • v.28 no.4
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    • pp.244-250
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    • 1984
  • Separation and identification of the polycyclic aromatic compounds (PAC) from pyrolysis products of cellulose and lignin were performed using a combination of acid-base solvent partitioning and silicic acid column chromatography with fused-silica capillary column gas chromatography/ mass spectrometry. Sixteen PAC were positively identifited by retention indices and mass spectra data. Both materials produced the same kinds of PAC. But lignin produced much more PAC than cellulose. Almost no highly carcinogenic heterocyclic PAC containing nitrogen and sulfur were produced.

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Analysis on Propellant Gauging System of KOREASAT-3 employing Thermal Mass Method (열질량법을 사용한 무궁화위성 3호의 잔여연료량 추정에 관한 연구)

  • 박응식;박봉규;남문경
    • Journal of the Korean Society of Propulsion Engineers
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    • v.5 no.1
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    • pp.60-68
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    • 2001
  • Thermal Mass Method(TMM) and its accuracy, utilized in the propellant gauging system of KOREA SAT-3, are described in the paper The residual in the fuel tank system of KOREASAT-3 is simulated using TMM based on the KOREASAT-3 data package An accuracy of TMM is calculated using analytical method and compared with the error analysis Monte Carlo methods.

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Direct Analysis of Organic Additives in Cured Rubber by Pyrolysis-Gas Chromatography/Mass Spectrometry (열분해-가스크로마토그래피/질량분석법에 의한 가황고무중의 유기첨가제의 직접분석)

  • Kim, Seung Wook;Heo, Gwi Suk;Lee, Gae Ho
    • Journal of the Korean Chemical Society
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    • v.41 no.10
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    • pp.524-534
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    • 1997
  • Analysis of additives in cured rubber is often a difficult task for analytical chemists because of a wide variety of complex components. Conventional analyses of additives and rubbers have been done in multistep, off-line processes with large sample size and extensive sample preparations. The coumarone-indene resin, resorcinol-formaldehyde resin, and prevulcanization inhibitor have been characterized by their pyrolysis pathways and mass spectra of characteristic pyrolyzates. Pyrolysis Gas Chromatography/Mass Spectrometry (Py-GC/MS) was used in the identification of additives without any sample pretreatment. This result shows that several organic additives in cured rubber can be directly analyzed.

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Thermal Ion Mass Spectrometry with Isotope Dilution Method: An application to Rare Earth Element Geochemistry (동위원소희석법을 이용한 열이온 질량분석: 희토류원소 지구화학에의 응용)

  • ;;;增田彰正
    • The Journal of the Petrological Society of Korea
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    • v.10 no.3
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    • pp.190-201
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    • 2001
  • Isotope Dilution Mass Spectrometry(IDMS) is one of the analytical method which uses enriched isotope spikes and analyzes the abundance of element by comparison of the spectrum between spiked mass and non-spike mass. Especially, the Thermal Ion Mass Spectrometry with isotope dilution technique (in general ID-TIMS) is the most accurate method of the chemical analysis, which enables us to obtain the data better than 1% in accuracy and precision. In IDMS, enriched isotope spike is one of the most important factor in order to obtain the best data. For rare earth elements, in general, a mixture of /sup 138/La, /sup 142/Ce, /sup 145/Nd, /sup 149/Sm, /sup 151/Sm, /sup 151/Eu, /sup 157/Gd, /sup 163/Dy, /sup 167/Er, /sup 171/Yb, and /sup 176/Lu is used as composite spike. IDMS is very useful in geochronology and REE geochemistry. Especially, it is very effective in studying the “tetrad effect” of rare earth elements in natural samples.

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A Study on the Heat Release Rate of EPS Sandwich Panel Core (EPS 샌드위치 패널 심재의 열방출율에 관한 연구)

  • Park, Hyung-Ju;Cho, Myung-Ho
    • Fire Science and Engineering
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    • v.22 no.5
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    • pp.72-78
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    • 2008
  • The mass loss rate and heat release rate of EPS sandwich panel cores were analysed using variable external irradiation level. The experimental materials were exposed to incident heat fluxes form 20 to 50 kW/$m^2$. For the measurement of mass loss rate and heat release rate, the size of specimen was $100mm{\times}100mm{\times}50mm$ and the samples were 3 different kinds. The combustion heat were carried out from the Oxygen bomb calorimeter and the mass loss rate and heat release rate were carried out from the Mass loss calorimeter according to ISO 5660-1. As the results of this study, the mass loss rate of Type A, B, and C were 2.7 g/$m^2s$, 2.8 g/$m^2s$, and 2.3 g/$m^2s$ and the heat release rate of Type A, B, and C were 58.23 kW/$m^2$, 47.19 kW/$m^2$, and 50.06 kW/$m^2$ respectively at the heat flux of 50 kW/$m^2$. In conclusion, when the heat release characteristics applied to a classification system of Canada, Type A and C can be classified grade C-3, and Type C can be classified grade C-2 from all data of this study.