• Proceedings of the KSME Conference
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• 2001.06d
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• pp.884-889
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• 2001

Combustion chamber crevices in SI engines are identified as the largest contributor to the engine-out hydrocarbon emissions. The largest of crevice region is the piston ring pack crevice. To predict and understand the oxidation process of piston crevice hydrocarbons, a 3-dimensional numerical simulation method was developed. A engine shaped computational mesh with moving grid for piston and valve motions was constructed. And a 4-step oxidation model involving 7 species was used and the 16 coefficients in the rate expressions were optimized based on the results from a detailed chemical kinetic mechanism for the oxidation condition of engine combustion chamber. Propane was used as a fuel in order to eliminate oil layer absorption and liquid fuel effect.

• Tribology and Lubricants
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• v.16 no.1
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• pp.22-26
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• 2000

In this paper, the fuction of Zinc-dialkyldithiophosphate (ZnDTP) as an oxidation ingibitor of mineral oils was investigated and compared with 2,6-Di-tert-Butyl-4-Methylphenol (DBMP). Oxidation tests were conducted using an oxygen absorption apparatus. ZnDTP showedanti-oxidation property, and length of induction period prolonged by increasing ZnDTP concentration. The anti-oxidation property of ZnDTP was simmilar to that with DBMP. The amount of hydroperoxide decomposition ability with ZnDTP was much greater than that with DBMP, But the rate constant of radical scavenging with ZnDTP was less than that with DBMP. The anti-oxidation property of ZnDTP seems to by both synergy effect of hydroperoxide decomposition ability and radical scavenging ability.

• Journal of Aquaculture
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• v.14 no.1
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• pp.17-27
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• 2001

Effects of temperature (10, 12, 14, 16, 18 and 2$0^{\circ}C$) and salinity (22.0, 24.5, 27.0, 29.5, 32.0 and 34.5 ppt) were studied on incubation period, hatching success, survival and growth of alevin and juvenile seabass, L. japonicus. Embryonic development was accelerated with increasing temperature but it was not influenced by salinity. Hatching success was the highest at 14$^{\circ}C$ and 34.5 ppt. Higher temperature also accelerated the development of mouth opening, absorption of yolk and oil globules, and alevin growth. Survival of the 5-day old Juvenile was accelerated in the following order : 14<16<18<20<12$^{\circ}C$. Rearing experiment of the juvenile for 30-day indicated the faster growth at 13, 20 and 27 ppt than at 34 ppt.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.5
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• pp.112-119
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• 2015

The pulp mold attract the increasing concern as recyclable, biodegradable, and eco-friendly packaging materials. In order to broaden the applicability of the pulp mold as substitutes of the expanded styrofoam, the properties of various raw materials for the pulp mold were evaluated and the way for improving water resistance properties of the pulp mold were also tested by applying some additives. The higher value in the fines contents and in the water retention value were shown for the TMP (thermomechanical pulp), which resulted in the bulkier pulp mold with the higher moisture absorption property. In case of water resistance properties, the pulp mold made of white ledger stock showed the higher value in water contact angle and very slow water absorption rate. The addition of oil palm EFB fiber showed the improvement in the water resistance of the pulp mold made of UBKP. The effects of various additives on the improvement in the water resistance properties of the pulp mold were tested by using AKD, PVAm, epoxy resin. The application of AKD leaded to the higher increase in the water resistance. The results in this study showed the effects of AKD for the pulp mold could be improved and optimized by the application with fixing agent and by the ageing treatment after production.

• Journal of Mechanical Science and Technology
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• v.17 no.6
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• pp.888-895
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• 2003

Combustion chamber crevices in SI engines are identified as the largest contributors to the engine-out hydrocarbon emissions. The largest crevice is the piston ring-pack crevice. A numerical simulation method was developed, which would allow to predict and understand the oxidation process of piston crevice hydrocarbons. A computational mesh with a moving grid to represent the piston motion was built and a 4-step oxidation model involving seven species was used. The sixteen coefficients in the rate expressions of 4-step oxidation model are optimized based on the results from a study on the detailed chemical kinetic mechanism of oxidation in the engine combustion chamber. Propane was used as the fuel in order to eliminate oil layer absorption and the liquid fuel effect. Initial conditions of the burned gas temperature and in-cylinder pressure were obtained from the 2-zone cycle simulation model. And the simulation was carried out from the end of combustion to the exhaust valve opening for various engine speeds, loads, equivalence ratios and crevice volumes. The total hydrocarbon (THC) oxidation in the crevice during the expansion stroke was 54.9% at 1500 rpm and 0.4 bar (warmed-up condition). The oxidation rate increased at high loads, high swirl ratios, and near stoichiometric conditions. As the crevice volume increased, the amount of unburned HC left at EVO (Exhaust Valve Opening) increased slightly.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.2
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• pp.114-123
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• 2017

This study added black lentil ethanol extract to Yakgwa at ratios of 0%, 0.5%, 1.0%, and 2.0%, and its quality characteristics were compared to those of the synthetic antioxidant BHT added to Yakgwa. Yakgwa with black lentil extract had lower moisture content than Yakgwa with BHT (3.98%) but higher content than the control group (5.72%). Higher black lentil extract resulted in less moisture content (p<0.001) as well as a faster expansion rate and oil absorption rate (p<0.001). Scanning Electron Microscopy (SEM) showed that as black lentil extract content increased, pores merged and collapsed, whereas the number of pores decreased and pore size became larger. For chromaticity, all L, a, and b values of the group containing black lentil extract were higher compared to the control group and group with BHT (p<0.001). For texture, as amount of added black lentil extract increased, hardness (p<0.001) and gumminess (p<0.01) increased while cohesiveness (p<0.01) decreased compared to the control group. For sensory characteristics, Yakgwa with 1.0% black lentil extract showed the best preference for all items except for off-flavor. Thus, 1.0% black lentil added to Yakgwa was the best in terms of functionality including preference.

• Korean journal of food and cookery science
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• v.32 no.1
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• pp.50-57
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• 2016

In this study, kim (dried laver) bugak ("KB"), Aster yomena bugak ("SB"), and namul (vegetables)-kim bugak (combination of Aster yomena and kim) ("NB") were prepared and their quality characteristics were investigated. NB was made by slicing Aster yomena, seasoning it with perilla seeds, attaching it to kim and applying glutinous rice paste, followed by freeze-drying. SB had a higher oil absorption rate than KB, reflecting the high oil absorption rate of namul (here, Aster yomena). DPPH radical scavenging activity was highest for SB; whereas, NB had higher DPPH radical scavenging activity than KB, indicative of the higher antioxidant capacity of namul, as compared to kim. With longer storage period, moisture content tended to be increased, while maximum load, yield stress and hardness tended to be decreased. Overall preference was in the order of NB>KB>SB, without statistical significance. Acid value and peroxide value of NB, stored at $25^{\circ}C$ for 40 days, tended to be increased gradually but did not meet the criteria for rancidity. Therefore, NB could be stored at $<25^{\circ}C$ for > 40 days. Furthermore, it would be possible to make functional bugak using a variety of namul, as well as Aster yomena.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.924-930
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• 1999

To extract insoluble proteins and improve physical properties of proteins, the sesame meal proteins was irradiated with $5\;kGy{\sim}20\;kGy$ at room temperature. The highest extraction rate of sesame meal protein was showed at irradiation dose of 5 kGy. The foaming capacity, foaming stability, emulsion capacity and emulsion stability of gamma irradiated sesame meal protein (GISP) were all increased as compared to those of the non-irradiated protein. Water absorption capacity of GISP was similar to that of non-irradiated protein and oil absorption capacity of GISP was decreased after treatment by gamma irradiation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.57-63
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• 2000

To extract insoluble proteins from abolished soybean meal, the meal was treatesd with phytase and protease produced by Aspergillus sp. SM-15 and Aspergillus sp. MS-18. The extraction of insoluble soybean protein was increased at alkaline range more than pH 5 in case of phytase, pH 7 to 11 in case of protease and pH 5 to 12 in case of the mixed enzyme of phytase and protease. The optimum extraction temperature of insoluble protein was 5$0^{\circ}C$ for phytase and the mixed enzyme of phytase and protease, and 6$0^{\circ}C$ for protease. The optimum treatment time for extraction of protein was 9 hrs for phytase, 11 hrs for protease and the mixed enzyme of phytase and protease and optimum unit of enzyme for extraction of protein was 600 unit, 40 unit and 900 unit＋60 unit in case of phytase, protease, phytase and protease, respectively. The treatment of mixed enzyme showed higher extracton rate of protein than single enzyme treatment. The foaming capacity, foaming stability, emulsion capacity, and emulsion stability of soybean meal protein by the treatment of the enzymes increased at all pH range. Further more oil absorption as well as water absorption capacities by the treatment of the enzymes were also increased. The functional properteis of the soybean meal protein treated by the mixed enzyme were higher than those of soybean meal protein treated by the single enzyme.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.24-29
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• 1986

Experiments were conducted to know the inorganic compound absorption of leaf, and the organic component, oil content, fatty acid composition of seeds by different fertilizer levels and growth stage of Pungn-yeonggage. Ripening rate and seed yield were highest under the standard of nitrogen fertilizer level. Nitrogen and potassium amount of leaves were highest at 20 days after seedlings, but there was no difference in phosphate between growth stages. Absorptions of nitrogen and potassium were increased by applying double amount of nitrogen fertilizer. Oleic fatty acid content was found highest under the double amount of nitrogen, phosphate and potassium fertilizer level, and linoleic fatty acid content was increased with double amount of phosphate fertilizer level.