• Journal of the Korean Society of Tobacco Science
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• v.2 no.2
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• pp.1-7
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• 1980

Less-volatile organic components in leaves from aromatic tobaccos of different varieties, both Oriental and Korean types were isolated and concentrated using a simple apparatus with fewer manipulations. Each less-volatile concentrate was then subjected to spectrophotometric recording in the visible range, to thin-layer chromatographic group separation, and high-performance liquid chromatographic profile analysis. The methods allow detection of significant quantitative differences in visible absorption spectra, TLC patterns, and high resolution HPLC profiles among varieties.

• Journal of Environmental Health Sciences
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• v.30 no.5 s.81
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• pp.487-492
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• 2004

Building materials are composed of very complex chemical compounds, and these indoor building materials discharge very much Volatile Organic Compounds(VOCs). We performed the environmental chamber test to investigate the Total VOCs(TVOCs) emission characteristics and emission factors about chemical and natural coating materials. As the result, we concluded that TVOCs emission are high at initial time and decreased in course of time. Natural paint was low emission level for TVOCs than chemical paint by small chamber test. The TVOCs emission factor-time profile showed a good fit with the results from the measured and predicted value.

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.3
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• pp.233-240
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• 2001

The composition of volatile organic compounds (VOCs) was anlyzed for major emission sources such as vehicle exhaust, gasoline and diesel vapor, organic solvent vapor, and butane fuel gas. Low carbon-numbered hydrocarbons were found to be the dominant components of gasoline vehicle exhaust. In gasoline evaporative vapor, the predominant constituents were found to be butane and iso-pentane regardless of ambient air temperature. In case of diesel evaporative vapor was similar to those of gasoline evaporative vapor. The composition of organic solvent vapor from painting, ink and petroleum consisted mostly or aromatic compounds such as toluene and m, p, o-xylene. The hydrocarbon fraction of butane fuel gas. which is used by portable bunner, consisted mainly of propane (34%) and butane(70%).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.103-104
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• 2006

PRAM (Phase change Random Access Memory) is one of the most promising candidates for next generation Non-volatile Memories. The Phase change material has been researched in the field of optical data storage media. However, the characteristics required in solid state memory are quite different from optical ones. In this study, the reset current and temperature profile of PRAM cells with bottom electrode were calculated by the numerical method.

• IEIE Transactions on Smart Processing and Computing
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• v.5 no.4
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• pp.274-282
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• 2016

This paper proposes code optimization techniques to reduce energy consumption of complex multimedia applications in a hybrid memory system with volatile dynamic random access memory (DRAM) and non-volatile spin-transfer torque magnetoresistive RAM (STT-MRAM). The proposed approach analyzes read/write operations for variables in an application. Based on the profile, variables with a high read operation are allocated to STT-MRAM, and variables with a high write operation are allocated to DRAM to reduce energy consumption. In this paper, to optimize code for real-life complicated applications, we develop a profiler, a code modifier, and compiler/link scripts. The proposed techniques are applied to a Fast Forward Motion Picture Experts Group (FFmpeg) application. The experiment reduces energy consumption by up to 22%.

• Food Science of Animal Resources
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• v.40 no.4
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• pp.497-511
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• 2020

This study aimed at comparing the storage stability, fatty acids profile, volatile flavor compounds and eating quality of Hanwoo beef longissimus thoracis (LT) muscles between two marbling morphological groups (fineness and coarseness). The 1⁺ grade Hanwoo LT muscles were measured for marbling fleck morphology at the 13^th thoracic vertebrae location by using computerized image analysis. Results reveal that both marbling groups had similar proximate composition (protein, fat, moisture and collagen), color and technological quality traits (p>0.05). However, the coarse marbling group presented greater C18:2n6 and polyunsaturated fatty acids contents compared to the fine marbling group (p<0.05). Furthermore, the fine marbling group presented lower volatile basic nitrogen (VBN) and 2-thiobarbituric acid reactive substance (TBARS) contents compared to the coarse marbling group after 14 d storage (p<0.05). Also, higher amounts of C18:2n6 oxidation-derived volatile compounds such as hexanal and 3-ethyl-2-methyl-1,3-hexadiene, were found in the coarse marbling group. In term of sensory aspects, the finely-marbled group received higher scores of flavor and taste compared to the coarse marbling group (p<0.05). Overall, the marbling flecks morphology partially showed its effects on the storage stability, fatty acids profile and eating quality of the 1⁺ grade Hanwoo beef LT muscle.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.322-328
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• 1999

Volatile flavor components of watermelon (Citrullus vulgaris S.) and oriental melon (Cucumis melo L.) obtained by simultaneous steam distillation and extraction apparatus were separated by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). Thirty seven and fifty five volatile flavor components were identified in watermelon and oriental melon, respectively. (Z)-3-Nonen-1-ol, (Z,Z)-3,6-nonadien-1-ol, (E,Z)-2,6-nonadienal and (E)-2-nonenal containing unsaturated nine carbon atoms were the characteristic flavor components of watermelon. $C_{9}-Unsaturated$ esters including (Z)-3-nonenyl acetate, (Z)-6-nonenyl acetate, (Z,Z)-3,6-nonadienyl acetate and thioester were important components in the flavor profile of oriental melon.

• The Korean Journal of Community Living Science
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• v.16 no.4
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• pp.15-24
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• 2005

We investigated the changes of volatile flavor components from Codonopsis lanceolata, which were packed in woven polypropylene(WP) film or low density polyethylene(LDPE) film and stored for 15 and 30 days at refrigerated($2{\∼}4^{\circ}C$ ) or room($18{\∼}20^{\circ}C$) temperature. A hundred and sixty seven volatile flavor components in the fresh C. lanceolata were identified by GC/MS analysis. When determining the flavor components from C. lanceolata cultivated on a wild hill and stored at 4 conditions for 30days, six volatile components such as 1-hexadecene, 2,6-dimethyl-2-octanol, 2-methyl-2-dodecanol, $\alpha$-guaiene, $\delta$-cadinene and trans-2-hexen-1-ol were detected as common components of all stored samples, and The types of common flavor components of C. lanceolata were different according to storage conditions. The numbers were 16 from refrigerated, 7 from room temperature stored, and 10 components from WP or LDPE packed conditions, respectively. The total peak area ratio of the major 10 compounds were $52.0{\∼}86.8\%$, and the percentage of trans-2-hexen-1-ol, which was the only common compound among the major 10 components, was the highest as $26.4{\∼}68.1\%$ The major flavor profile, describe by highly trained panel, were green, aldehydic, earthy and camphoreous. As the result from sensory evaluation, the freshness of C. lanceolata was maintained better by controlling storage temperature rather than selection of package materials. The best condition for characteristic flavor of C. lanceolata was packing with LDPE and chilling.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.892-898
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• 2005

The effect of gamma irradiation on volatile components of Korean dried ginger (Zingiber officinale Roscoe) was studied and compared with non-irradiated sample. Volatile compounds from non- and irradiated samples were extracted using simultaneous distillation-extraction (SDE) apparatus and analyzed by gas chromatography-mass spectrometer (GC/MS). A total of 83 and 71 compounds were identified and quantified from non-and irradiated dried ginger at dose of 10 kGy. Identified components were hydrocarbons, alcohols, aldehydes, esters, ketones and miscellaneous compounds. The terpenoid compounds in volatile flavor compounds identified from non and irradiatied dried ginger were $98.27\%\;and\;98.12\%$, respectively. $\alpha$ -zingiberene,$\beta$-sesquiphelland reno, geranial, (Z,E) $\alpha$ -farnesene, $\beta$ -phellandene were detected as major volatile compounds of two experimental sample. The amount of volatile components in the samples was changed by irradiation but the profile of volatiles in non- and irradiated dried ginger were the same.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.438-446
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• 2019

To investigate the changes in volatile compounds of persimmon vinegar (PV) during aging, PVs aged for 3-25 years were analyzed using solid-phase microextraction-gas chromatography-mass spectrometry. In total, 90 volatile compounds were identified, and acids and esters were the most abundant, followed by ketones and alcohols. The concentration of acetic acid ranged from 8,925.0 to 26,132.3 ng/mL, depending on the aging period. Ethyl acetate concentration ranged from 32.5 to 50,681.7 ng/mL and ethanol was present only in PV aged for 3 years (PV-3). The volatile compound content was the highest in PV-3. The volatile profiles of PV aged for 22 years (PV-22) and 25 years (PV-25) were considerably similar. Acids were the most predominant in PV-15, PV-22, and PV-25, whereas esters were abundant in PV-3. The contents of acids, alcohols, and esters decreased, while the aldehyde and ketone content increased with aging.