• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.3
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• pp.437-450
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• 1996

A set of stability equations is formulated for natural convection flows adjacent to a vertical isothermal surface melting in cold pure water. It takes account of the nonparallelism of the base flows. The melting rate is regarded as a blowing velocity at the ice surface. The numerical solutions of the linear stability equations which constitute a two-point boundary value problem are accurately obtained for various values of the density extremum parameter $R=(T_m-T_{\infty})/(T_0-T_{\infty})$ in the range $0.3{\leq}R{\leq}0.6$, by using a computer code COLNEW. The blowing effects on the base flow becomes more significant as ambient temperature ($T_{\infty}$) increases to $T_{\infty}=10^{\circ}C$. The maximum decrease of heat transfer rate is about 6.4 percent. The stability results show that the melting at surface causes the critical Grashof number $G^*$ and the maximum frequency of disturbances to decrease. In comparision with the results for the conventional parallel flow model, the nonparallel flow model has a higher critical Grashof number but has lower amplification rates of disturbances than does the parallel flow model. The spatial amplification contours exhibit that the selective frequency $B_0$ of the nonparallel flow model is higher than that of the parallel flow model and that the effects of melting are rather small. The present study also indicates that the selective frequency $B_0$ can be easily predicted by the value of the frequency parameter $B^*$ at $G^*$, which comes from the neutral stability results of the nonparallel flow model.

• Journal of Life Science
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• v.13 no.4
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• pp.481-491
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• 2003

A squid meat has not been utilized for gel products because of its lower gel forming ability. The objectives of this study were as followed; 1) the optimum heating condition on squid meat paste products and 2) the optimum added level for jelly strength of squid meat paste products. Optimum heating conditions of squid meat kamaboko were as followed; setting (pre-heating) at 15$^{\circ}C$ or 55$^{\circ}C$ for 2 hours and heating at 90$^{\circ}C$ for 60 minutes. Effect for jelly strength of starch additives wheat starch, potato starch and com starch were examined. The jelly strength of heat induced gels differed from the levels of additives. In case of adding starch, potato starch was resulted in the superior jelly strength than the other starchs, wheat starch and corn starch, at any levels. Optimum concentration was 10%(w/w) at every additives. Folding test value was B at added 10% and this value was mean good product. Data of jumbo and flying squid meat paste products added potato starch, corn starch and wheat starch of 10% were shown below, jelly strengths were 858${\pm}$34∼1020${\pm}$37gㆍcm and 966${\pm}$33∼l148${\pm}$45gㆍcm and moisture contents were 72.43∼73.04% and 71.61∼72.78%, respectively. To adding edible agar and sea tangle, showed the highest jelly strength (edible agar>sea tangle, flying squid>jumbo squid) at added 0.5%(w/w) concentration.

• Journal of Environmental Science International
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• v.30 no.2
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• pp.135-143
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• 2021

This study executed evaluation of drying characteristics based on the polymer injection rate (8%, 10% and 12%) and the drying method[NIF(near-infrared ray). According to this study analyzed VS, VS/TS, and calorific value compared with 'the auxiliary fuel standard of the thermoelectric power plant and the combined heat & power plant'. The results are as follows. In the case of NIR, the VS was slightly changed at the early stage of the material preheating period and the constant drying rate period with low moisture evaporation. But VS reduction was shown higher as moisture was dried. In the case of non-digested sludge with high VS content, the VS reduction rate by drying was shown lower than that of digested sludge. As the flocculant injection rate increased, the VS loss due th drying was found to be small. Also, the higher the flocculant injection rate was the longer the drying time. Especially, in the case of the NIR drying equipment, as the moisture content of sewage sludge decreased(moisture content 20~40%), the loss of net VS also showed a tendency to increase sharply. It is shown that the high calorific value according to the drying time of the non-digested sludge was changed from 590 kcaℓ/kg to 3,005 kcaℓ/kg and from 539 kcaℓ/kg to 2,796 kcaℓ/kg.

• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.770-776
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• 2018

This study measured the energy recovery rate of each municipal waste incineration facility according to the revised energy recovery rate estimation method, which targeted four municipal waste incineration facilities (Unit No. 7). The results calculated by the measuring instruments were used for each factor to estimate the recovery rate, and the available potential of available energy was examined by analyzing the energy production and valid consumption. As a result of the low heating value, 2,540 kcal/kg was calculated on average when the LHVw formula was applied, which is approximately 116 kcal/kg higher than the average design standard of 2,424 kcal/kg. The energy recovery rate was calculated as 96.9% on average based on production and 67.5% based on effective consumption, and the analysis shows that approximately 29.4% energy can be used.

• Journal of the FoodService Safety
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• v.2 no.1
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• pp.44-50
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• 2021

Physicochemical and antioxidant properties of the three different calorie types of HMR curry rice using fermented turmeric were analyzed in this study. The general tumeric added sample groups showed significantly higher carbohydrate content than the fermented turmeric sample group. In all sample groups, the ratio of protein, fat, and carbohydrate was found to be appropriate according to the nutritional composition ratio as one meal recommended by the Ministry of Health and Welfare. The brightness L value of the general turmeric-added sample group was measured to be significantly brighter than the fermented turmeric-added sample group. The fermented turmeric sample group showed a slightly lower pH value than the general sample group due to organic acids generated during fermentation. As a result of analyzing the radical scavenging activity of ABTS, LFTC, MFTC, and HFTC of the fermented turmeric group were 40.20, 40.46, and 36.16%, respectively, compared to those 32.41, 37.75, and 36.16% of LNTC, MNTC and FNTC of the general sample groups, respectively, consistently indicating that more free radicals were generated in the fermented sample group (p<0.01). Relatively unstable to heat and acid, DPPH scavenged radicals showed similar results to those of ABTS radical scavenging activity in terms of activity. Similar results were also shown in the measurement of total flavonoid and phenol content, which are known to have antioxidant antiviral and anticancer effects. Thus we could conclude that pilot products of the high quality varied calorie levels of HMR Bibimbap set with tumeric, which is helpful for antioxidant action have been developed to meet various customer needs.

• Journal of Food Hygiene and Safety
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• v.24 no.3
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• pp.204-210
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• 2009

Antioxidative activities of fresh, steamed and black garlics by different processing condition were investigated on the soybean oil. The crushed fresh, steamed and black garlics were added to 100 mL of soybean oil at a level of 0, 5, 10,20 and 40 g respectively, and then the oil mixture containing garlics (reaction samples) were heat-treated for 48 hrs at $180^{\circ}C$. The chromaticity of reaction samples were increased during heating. After 48 hrs heating, in the sample added 40 g/ 100 mL chromaticity of each samples were 1.36, 2.99 and 1.99, in the crushed fresh, steamed and black garlics, respectively. Anisidin value showed irregularly increased during heating. Acid values of reaction samples were higher than control during heating, those levels were ranged from 0.82 to 2.04 mg/g after 12 hrs, were gradually increased to $3.15{\sim}4.30\;mg$/g after 48 hrs. Peroxide value of reaction sample containing black garlic(40 g/ 100 mL) was lower than the samples containing tocopherol or BHT, after 48 hrs heating. TBA value of reaction samples containing fresh, steamed and black garlic of 40 g/ 100 mL were the lowest in the sample added black garlic, after 48 hrs heating. These results suggested that oxidative stability of black garlic in soybean oil was more potential than the other garlics during heating.

• Korean journal of food and cookery science
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• v.12 no.1
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• pp.6-12
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• 1996

The survival and growth of Vibrio parahaemolyticus in tryptic soy broth(TSB), flounder homogenate and oyster homogenate with 0 or 5% of ethanol was tested at -20, 5, 35, 45 and 50$^{\circ}C$. Growth pattern of V. parahaemolyticus was similar in TSB and flounder homogenate but slightly poor in oyster homogenate at 35$^{\circ}C$. Growth occured at 5% ethanol, in TSB and flounder homogenate after a prolonged lag period but decreased in oyster homogenate during incubation at 35$^{\circ}C$. TSB and fish homogenates containing 0 or 5% of ethanol were inoculated with 10$\^$6/-10$\^$7/ cells/ml of V. parahaemolyticus and cold or heat resistance of the cells were determined at -20, 5, 45 and 50$^{\circ}C$. At 5$^{\circ}C$, the viability in culture broth with 5% of ethanol or without ethanol was not vary with the culture broth. In the presence of 5% of ethanol at -20$^{\circ}C$, cells of V. parahaemolyticus in flounder homogenate and oyster homogenate were more significantly inhibited than in TSB. The D-valves for V. parahaemolyticu at 45 and 50$^{\circ}C$ was significantly lower in oyster homogenate than in TSB and flounder homogenate with 5% of ethanol or without ethanol. The D-values in each culture broth without ethanol were 1.9-3.5 times of that value in each culture broth containing 5% of ethanol at 45 and 50$^{\circ}C$.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.519-528
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• 2002

It is not a rare occasion that certain dental procedures involving tooth reduction being peformed under inadequate water cooling due to a variety of reasons. This situation could possibly inflict the critical insult to the pulpal tissue of indicated tooth. The purpose of this experiment was to study the pattern of diffusion of external heat produced during routine dental procedures into the pulpal tissue. 30 stone blocks containing three lower second primary molars were used for certain restorative procedures and the temperature of the indicated tooth surface was measured by thermography(Inframetrics 600) and further used as a baseline data for the finite element analysis model fabrication designed in order to evaluate the pattern of thermal diffusion. The ranges of highest surface temperature measured from several dental procedures under water cooling and non-water cooling were $30.8^{\circ}C{\sim}43.6^{\circ}C$ and $51.2^{\circ}C{\sim}103.4^{\circ}C$ respectively. Among procedures studied, crown preparation showed the highest value and amalgam removal showed the lowest. Comparisons between data measured under water cooling and non-water cooling conditions have shown the statistically significant difference(p<0.05). All the non-cooling conditions have shown the relatively larger increment of temperature change at the pulp horn area than the cooling conditions. The results of this study strongly indicate that the water coolant is the essential element in restorative procedures for the maintenance of healthy pulp. Further related studies involving more procedures and conditions are recommended.

• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.698-705
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• 1994

The basic medium oil modified alkyd resin was synthesized from linseed oil fatty acid(LOFA), phthalic anhydride(PAA), maleic anhydride(MA) and trimethylol propane(TMP) by condensation polymerization at $230^{\circ}C$. MA/TMPTA modified water-reducible alkyd resins were synthesized with TMPTA graft copolymerization onto the basic resin at $180^{\circ}C$. Acid value of the resin was controlled by the addition amount of MA and N,N-dimethylethanol amine(DMEA) was used as a neutralizing agent to prepare of the water-reducible alkyd resin. The effect of TMPTA on the graft copolymerization of the resin was studied by measuring molecular weight glass transition temperature(Tg), viscosity, graft efficiency, and gel contents of melanin cured film. Heat resistance, UV resistance and water resistance of cured film of MA/TMPTA modified resin was compared to those of TMA/TMPTA modified alkyd resin. The molecular weight, viscosity gel contents and graft efficiency of water reducible alkyd resin were increased according to the TMPTA graft copolymerization, but Tg was decreased. The viscosity was lower when the solid contents reached 40% than that of 30% content and also and also became lower with the extent of neutralization ratio, The heat resistance, UV resistance and water resistance of the MA/TMPTA modified alkyd resis were better than those of TMA/TMPTA modified alkyd resin but the storage stability of the TMA/TMPTA alkyd resis was better than that of MA/TMPTA modified alkyd resin.

• Solar Energy
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• v.16 no.2
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• pp.113-122
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• 1996

This study presents experimental results of heat transfer characteristics of P.C.M. during outward melting process in a vertical cylinder. The experiment was carried out in six conditions, i. e., three different inlet temperature($7^{\circ}C,\;4^{\circ}C\;and\;1^{\circ}C$) and two directions of working fluid(upward and downward). Melting P.C.M. produced a bell-shaped phase change interface. When the inlet temperature was $7^{\circ}C$, the lower region remained at $4^{\circ}C$ until the temperature of upper region reached $4^{\circ}C$. This was due to the state of maximum density of the lower region. When the direction of the working fluid in the case of $7^{\circ}C$, inlet temperature, was upward, the rate of melting and the total melting energy were higher than when it's direction was downward. But the rate of melting and the total melting energy appeared higher value as it's direction was downward when the inlet temperature is $4^{\circ}C$ and $1^{\circ}C$.