• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.4
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• pp.451-460
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• 2001

An analysis program for the thermal performance prediction of steam turbine cogeneration systems with multi-extraction, reheat and regeneration has been developed on the basis of the thermodynamic heat balance method. Heat balance analyses were performed for a commercial cogeneration power plant using the program. Its appropriateness was verified by comparing its heat balance results with those of other commercial programs and those provided by the original system designer. Further parametric analyses were carried out and performance improvement measures in designing the plant were suggested.

• Fisheries and Aquatic Sciences
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• v.11 no.3
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• pp.140-148
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• 2008

We compared the quality and quantity of volatile components in salt-dried croakers prepared by different methods and obtained from different locations. In total, 110 compounds were found among regular- and delay-type salt-dried croakers purchased from two locations in Hong Kong. The major chemical classes included miscellaneous compounds(17), pyrazines(16), alcohols(15), and sulfur-containing compounds(13). Fish obtained in different locations but prepared by the same method differed only slightly in the number of identified compounds. In general, fish prepared by the delay method had a larger number of compounds compared to fish prepared by the regular method. Further, a greater number and higher levels of compounds were found in the fish obtained from one of the two locations. Overall, the delay preparation method resulted in a greater number of compounds with stronger intensity compared to the regular method.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.494-501
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• 1993

The volatile flavor components of traditional and commercial kochujang were collected by simultaneous steam distillation-extraction (SDE) method. Essential oils were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC/MS). Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley, Sachun kochujang prepared with wheat and commercial kochujang. One hundred and twelve volatile flavor components which included 30 esters, 15 alcohols, 14 aldehydes, 13 acids, 9 ketones, 7 alkenes, 6 phenols, 3 alkanes, 3 pyrazines, 2 benzenes and 2 furans were identified. The major volatile compounds in traditional and commercial kochujang were 2-methyl propanal and ethanol, which represented $21{\sim}36%\;and\;2{\sim}44%$ of total GC peak area, respectively.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.129-132
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• 1991

The volatile components of Perillae folium were isolated by simultaneous steam distillation-extraction method, and analyzed by combined GC and GC-MS. Among seventeen components indentified 6 alcohols (3-octanol, 1-octen-3-ol, linalool, nerolidol, supathuleol and phytol), 2 ketones, 1 aldehyde, 1 phenol and 7 hydrocarbons were confirmed. The most abundant component was myristicin comprising about 53.4%.

• The Korean Journal of Food And Nutrition
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• v.12 no.5
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• pp.513-517
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• 1999

Theessential oils of anise darkopal lettuce and sweet basils cultivated in Korea were extracted by simulatneous steam distillation and extraction method and were analyzed by GC/MSD. Total 41 com-ponents were identified in essential oils including 11 alcohols, 6 carbonyls 19 hydrocarbons and 5 esters components. The major components were 1,8-cineole linalool $\alpha$-bergamotene $\beta$-elemene methyl chavicol, $\beta$-cubebene methyl cinnamate and eugenol. Darkopal lettuce and sweet basils were rich in linalool(30.1-36.5%) methyl chavicol(8.1-25.5%) and relatively poor in methyl cinnamate(0-2.71%) Anise basil was rich in linalool(28.5%) and methyl cinnamate(23.1%) However methyl chavicol which was known as one of the main components of bisil was not detected.

• Applied Biological Chemistry
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• v.33 no.2
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• pp.116-119
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• 1990

The volatile components of the barks of Eucommia ulmoides Oliver were extracts simutaneous steam distillation-extraction apparatus, and analyzed by combined GC and GC-MS. Forty nine componets, including 4 acids, 11 alcohols, 9 aldehydes, 4 esters, 3 ketones, 16 hydrocarbons, 1 lactone were confirmed in Eucommiae cortexs. Among total volatiles the most component was caproic acid comprising about 18.1%.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.1-5
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• 1997

The volatile components of Lycium chinensis Miller were isolated by simultaneous steam distillation-extraction(SDE) method and analyzed by combined GC and GC-MS. Fifty-four volatile components, including 12 alcolhols 12 esters, 7 aldehydes, 6 acids, 5 ydrocarbons, 8 ketones, 1 furan and 3 pyrazines were confirmed in the fruit of Lycium chinensis Miller. The major components were hexadecanoic acid ethyl ester, 1-octadecanone, tetrapyrazine, 2-furancarboxaldehyde and ethyl linoleate.

• Journal of Electrical Engineering and information Science
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• v.2 no.4
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• pp.59-65
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• 1997

In this paper, a general fuzzy syntactic method for recognition of flaw patterns and for the measurement of flaw characteristic parameters for a non-destructive inspections signal, called eddy-current, is presented. Solutions are given to the subtasks of primitive pattern selection, signal to symbol transformation, pattern grammar formulation, and event-synchronous flaw pattern extraction based on the grammars. Fuzzy attribute grammars are used as the model for the pattern grammar because of their descriptive power in the face of uncertain constraints caused by nose or distortion in the signal waveform, due to their ability to handle syntactic as well as semantic information. This approach has been implemented and the performance of eh resultant system has been evaluated using a library of law patterns obtained from steam generator tubes in nuclear power plants by an eddy current-based non-destructive inspection method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.563-567
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• 1998

Volatile flavor components of edible portion of leek(Allium tuberosum R.) were extracted by SDE(simultaneous steam distillation and extraction) method using the mixture of n-pentane and diethylether (1 : 1, v/v) as an extract solvent and analyzed by GC-FID and GC/MS. Identification of the volatile flavor components was mostly based on the RI of GC and mass spectrum of GC/MS. A total of sixty-five components from leek extract were classified as 28 sulfur-containing compounds, 12 aldehydes, 9 alcohols, 4 lactones and esters, 3 acids and hydrocarbons, and 2 miscellaneous compouds. The sulfur-containing compounds were predominant in leek extract. Dimethyl disulfide(19.47%) and dimethyl trisulfide(17.38%) were the main compounds and trans-1-propenyl methyl disulfide, trans-2-hexenal and methyl allyl disulfide were also detected large amounts in leek.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.454-458
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• 1995

Alkylpyrazines in snow crab cooker effluent(SCCE) and effluent concentrate(EC) were quantitatively analyzed and compared by simultaneous steam distillation-solvent extraction/gas chromatography/mass spectrometry(SDE/GC/MS). A total of 11 pyrazines were identified in both SCCE and EC. Amounts of tetramethylpyrazine, 2,5-dimethylpyrazine, trimethylpyrazine, and 2,6-dimethylpyrazine were 23.0, 21.1, 13.8, and 13.3 times higher, respectively, in EC than those in SCCE. The total amount of pyrzines in EC (1664.0${\pm}$171.1ng/g) was 8.1 times higher than that in SCCE(204.5${\pm}$32.2). The compounds, ethylpyrazine and 2-ethyl-3,6-dimethylpyrazine, were only detected in EC.