• Korean Journal of Remote Sensing
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• v.32 no.6
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• pp.579-587
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• 2016

To obtain a stable energy supply and manage PhotoVoltaic (PV) systems efficiently, satellite imagery methods are being developed to estimate the solar PV potential. This study analyzed trends in the use of satellite imagery in solar PV and solar irradiation estimation technology. The imaging technology is used to produce solar energy resource maps. The trend analysis showed that the level of solar PV technology in Korea is 30% below that of advanced countries. It is impossible to raise such low-level technologies to the levels of advanced countries quickly. Intensive research and development is the only way to achieve the 80% technology level of advanced countries. The information produced in this process can contribute to the management of solar power plants. A valid technology development strategy would be to obtain effective data that can be used for fieldwork. Such data can be produced by estimating solar irradiation very accurately with several-hundred-meter resolution using Communication, Ocean, and Meteorological Satellites (COMS) and next-generation GEO-KOMPSAT 2A, developing core technologies for short- and medium-term irradiation prediction, and developing technologies for estimating the solar PV potential.

• Journal of Life Science
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• v.18 no.6
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• pp.865-870
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• 2008

The purpose of this study was to examine resting metabolic rate (RMR) and thyroid hormonal (TSH, $T_3$, and $T_4$) changes following weight loss by diet with regular exercise in obese women. The subjects of the present study were 7 women who were above 30% body fat. The subjects arrived into the laboratory in the morning after 12 hour overnight fasting. All subjects measured RMR, % body fat, and fat free mass at weight loss program start time, after 4 weeks and after 8 weeks. All the RMR values were expressed as absolute value (kcal/day), absolute value/FFM (kcal/day/FFM), and absolute value/BSA (kcal/$m^2$/hr), and were calculated predicted RMR value minus actual RMR value. Also, correlation of blood thyroid hormonal (TSH, $T_3$, and $T_4$) secretion and RMR were analyzed. There were significant differences in weight, % body fat, and BSA following diet with exercise (p<0.05). Also, there was a difference between predicted RMR and actual RMR value following weight loss (p<0.05). We also examined the hormonal changes according to weight loss. After weight loss, the level of TSH and $T_4$ were higher than before. But there were no significant differences. Also, the level of $T_3$ was lower than rather before but there was no significant difference. Among the anthropometric factors, FFM was highly correlated (r=0.761) with actual RMR value before weight loss. Also, there was a correlation (r=0.771) with actual RMR value after weight loss. Therefore, actual RMR expressed as FFM increased in weight loss program by diet with exercise. There were no changes in the level of thyroid hormonal TSH and $T_4$.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.300-304
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• 1994

To predict quality change of Kochujang distributed in the market, physicochemical properties were observed during storage at $13^{\circ}C$, $27^{\circ}C$ and $37^{\circ}C$ for 240 days. Moisture, crude protein and capsaicin contents were nearly constant for storage at the selected temperatures. Amino nitrogen, value of surface color and pH were decreased during storage while ammonia nitrogen and titratable acidity were increased. Storage temperature affected quality change significantly as higher temperature showed clear increase or decrease phenomena of above factors. Number of total cell count was not changed significantly, and fungi was not detected. From the correlation coefficient among physicochemical properties and sensory evaluation scores, the highest correlation was obtained in amino nitrogen content and sensory score. Degradation of amino nitrogen was a first order reaction, and the $Q_{10}$ value calculated from reaction constant was 2.98. Also, activation energy for the destruction of amino nitrogen calculated from Arrhenius equation was 15.34 Kcal/mole.

• Journal of the Korean Magnetics Society
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• v.15 no.1
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• pp.1-6
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• 2005

In this study we investigate the electronic structure and magnetism of transition metal (TM = Ti, Cr, Mn, Fe, Co, Ni, Ru, Pd, Ag ) deped ZnO($TM_{0.25}Zn_{0.75}O$), which are expected to have Curie temperature. Full-potential Linearized Augmented Plane Wave(FLAPW) metod is adopted with exchange-correlation potential expressed as general gradient approximation(GGA). The calculated magnetic moments of ($TM_{0.25}Zn_{0.75}O$) are 0.83, 3.03, 4.03, 3.48, 2.47, 1.56, 0.43, 0.75, 0.01 ${\mu}_B$ for TM = Ti, Cr, Mn, Fe, Co, Ni, Ru, Pd, Ag, respectively. The nearest neighbor O atom to the transition metal is calculated to have a significant magnetic moment of about 0.1${\mu}_B$, ?? 새 strong hybridization between O-p and TM-d bands. As the results, the systems may have larger magnetic moments in total, compared to the corresponding isolated atoms. The 3d TM doped systems exhibit the half-metallic character except Co, wheres the 4d TM doped systems behave like normal metals and low spin polarization at the Fermi levels.

• Journal of Applied Biological Chemistry
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• v.63 no.1
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• pp.1-8
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• 2020

This study investigated the processing characteristics of soybean (HaePum) sprouts based on temperature (5, 15 and room temperature), period (0, 6 and 12 mon) and relative humidity (20, 40, 60, and 80%) during storage. The initial germination rate of soybean sprouts was 76.02±6.32%, which significantly reduced to 57.18±8.51%, and 0% as the storage temperature of soybean increased for a period of 12 mon. The germination rate of soybean sprouts with 30 ℃ and 80% RH decreased after 4 mon of storage to 4.94%. The yellowness of cotyledon of soybean sprouts was not significantly changed during the 12 mon period of storage at 5 ℃, whereas, soybean sprouts stored at 15 ℃ and room temperature demonstrated decreased yellowness. However, the stress of cotyledon decreased with an increase in both storage temperature and time, and the hardness of hypocotyl decreased with an increase of storage time. The stress of cotyledon affected by high temperature (30 ℃) and humidity (80%) during 4 mon was reduced to 44.39±9.38 g/㎟. The asparagine content of soybean sprouts showed a similar result with the germination rate due to the amount of hypocotyl. Therefore, lower temperatures and shorter storage times are suitable for soybean sprout processing. The first order kinetic model and Arrhenius equation (activation energy =29.56 kJ/mol) were able to predict the yield of sprout at various storage temperatures and periods.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.415-423
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• 2007

Pyrolysis characteristics of sawdust and rice husk as biomass resources in a thermogravimetric analysis were determined. Experiments were carried out with a linear heating rate under inert atmosphere of $N_2$ gas. Pyrolysis of the biomass can be classified as a lower temperature reaction zone where the major component of holocellulose is thermally decomposed and a high temperature reaction zone where lignin is thermally decomposed. The obtained data was analyzed by the two-step consecutive reaction model. Activation energies of sawdust and rice husk are found to be respectively 82.5 kJ/mol and 85.1kJ/mol in the low temperature zone according to the first order reaction model and 19.7 kJ/mol, 22.0 kJ/mol in the high temperature zone according to the three-way transport model. The reaction rate constant with variation of heating rate can be well predicted by the kinetic compensation relation of Gaur-Reed.

• Korean Journal of Food Science and Technology
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• v.13 no.3
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• pp.188-193
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• 1981

Thermal degradation of pantothenic acid in potassium biphthalate buffer and in food samples such as rice, mushroom and beef was studied as functions of temperature and pH. Thermal degradation of pantothenic acid in buffer and food systems followed first order reaction at temperature between $60{\sim}104^{\circ}C$. Activation energy calculated from the Arrhenius equation ranged from 15,700 cal/mole 17,300 cal/mole for both systems. D values at $120^{\circ}C$ were approximately 18 hours for food samples and 15.4 hours at pH 5.65 for buffer sample. Z values of food samples were about $37^{\circ}C$, which were similar to those of buffer sample. The decomposition rate constant of pantothenic acid in buffer sample decreased when the pH increased from 4.0 to 6.46, but activation energy increased. In the range of $pH\;6.46{\sim}8.0$, decomposition rate constant increased but activation energy decreased as pH increased. The kinetic model of pantothenic acid decomposition in buffer system was proposed on the basis of empirical relationship.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.742-748
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• 1989

Rheological properties of gelatinized millet starch dispersions were evaluated. Gelatinized nonwaxy and waxy millet starch dispersion were typical pseudoplastic fluids. At constant shear rate, gelatinized waxy millet starch dispersion showed higher shear stress than nonwaxy millet starch dispersion. Flow behaviours of gelatinized nonwaxy and waxy millet starch dispersion were well fitted to Herschel-Bulkley equation and flow behaviour index (n) and consistency index (K) were strongly concentration dependent. There was a linear relationship between concentration of gelatinized starch dispersion and square root of yield stress. The concentrations of gelatinized nonwaxy and waxy millet starch dispersion where yield stresses become zero were estimated as 2.19 and 1.69%, respectively. Pseudoplastic constant (m) approaches to a constant value in each type of millet starch when the concentration of gelatinized starch dispersion was increased. As the measuring temperatures increase, n value was increased, whereas, K value was decreased. The activation energies of gelatinized nonwaxy and waxy millet starch dispersion were 2.89 and 3.18kcal/mol, respectively.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.51-58
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• 2008

Development of a new design guide which is based on empirical-mechanistic concept for pavement design is in action. It is called AASHTO 2002 Design Guide in USA and the KPRP(Korean Pavement Research Project) in Korea. The material characteristic of hot mix asphalt is a key role in the design guide. Therefore it is urgent to get a proper materials database, especially the dynamic modulus of hot mix asphalt. In this research, dynamic modulus test, which is based on aged asphalt binder, has been carried out and proposed the predicted equation of dynamic modulus. Nine different hot mix asphalt with three different asphalt binder have been used for the dynamic modulus test. Short-term aging, which is covers the time for the production of asphalt plant, transportation, lay-down, and compaction, can be simulated at $135^{\circ}C$ with 2 hour curing. Long-term aging has been carried out for a performance period of asphalt pavement. The dynamic modulus of asphalt pavement increases with aging time. As the nominal aggregate size increases, the change of dynamic modulus is not big.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.748-752
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• 1995

Canned and bottled orange juices currently sold in Korean market were stored for 24 weeks at 20, 30, 40 and $50^{\circ}C$ and analyzed after opening at 4 week intervals. Activation energy, $Q_{10}$ values and shelf-life at respective temperatures were calculated from the data on various quality indexes. Proposed indexes were lead, tin, iron and vitamin C contents in canned juices and vitamin C content and browning index in bottled juices and $Q_{10}$ values for these parameters were in the range of $1.3{\sim}2.0$. Shelf-life calculated for canned juices at 10, 20 and $30^{\circ}C$ were 10, 6 and 3 months and that in bottled juices, 24, 12 and 6 months, respectively. When the distribution temperature of juices in Korea is assumed to be $15^{\circ}C$ average, the optimum shelf-life was estimated to be 8 months in canned juices and 18 months in bottled juices. In order to ascertain the safety of canned orange juices, efforts are needed to re-examine the recommended distribution period, legal limit for lead and improvement of container materials.