• Journal of Hydrogen and New Energy
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• v.34 no.1
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• pp.32-37
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• 2023

In this study, in order to propose a integrity evaluation for type IV high aspect ratio hydrogen storage vessel, a numerical analysis of the hoop tensile test and pressure test was performed using FEM software, and the results of the actual physical property test were reviewed. The property test and numerical analysis were compared, and very similar results were obtained with deviations of maximum tensile strength of 4.75% and fiber direction stress of 5.39%.

• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.470-476
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• 1992

The curd yogurt was prepared from milk added with skim milk powder or three Tongil rices of different storage period. The effect of storage period of rice on acid production by lactic acid bacteria in milk containing rice of 2%(w/v) was investigated. The effect of storage period of rice on quality of curd yogurt(sensory property, viscosity and keeping quality) was also examined. Addition of rice stimulated acid production by lactic acid bacteria more than control(milk yogurt). Storage period of rice did not significantly affect acid production by lactic acid bacteria though stimulating effect of rice on acid production was slightly different among species. Sensory property of curd yogurt added with rice was not significantly affected by storage period of rice. Apparent viscosity of curd yogurt added with rice increased in proportion to storage period of rice. Curd yogurt showed characteristics of thixotropic flow. When curd yogurt added with rice was kept at $5^{\circ}C$ for 15 days, its keeping quality was relatively good and was not markedly affected by storage period of rice.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1119-1121
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• 2008

The effects of storage time (0, 1, and 2 month) and temperature (5, 15, and $25^{\circ}C$) on the dynamic rheological properties of hot pepper-soybean paste (HPSP) mixed with acetylated starches (AS) were studied by small-deformation oscillatory measurements. Dynamic moduli (G', G", and $\eta^*$) values of HPSP-AS mixtures increased with an increase in storage time and also decreased with increasing storage temperature. However, dynamic moduli values of the control (no added AS) were independent on storage time and temperature. Tan $\delta$ values (ratio of G"/G') in all HPSP samples did not change much with an increase in storage time and temperature. After 2 months of storage, the dynamic moduli of the HPSP-AS mixture samples were much lower than those of the control, indicating that the addition of AS can inhibit the retrogradation that developed over a long period of storage. Structural and rheological properties of HPSP samples seem to be stabilized by the presence of AS.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.1
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• pp.8-14
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• 2007

This paper addresses the allocation planning of the storage location in a warehouse system that the dedicated storage method is used. In the discrete finite time period model, the demands for storage location of products are dynamic for time periods. The planning is to determine the reallocation time period and the storage location of the products in reallocation time period, which minimizes costs. The cost factors are the reallocation cost, the travel cost within warehouse and the surplus storage location cost. A model is formulated, and the property of optimal solution is characterized. The dynamic programming algorithm is developed, and a numerical example is shown.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.2
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• pp.149-158
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• 2013

L-ascorbic acid, the representative antioxidants, has a great effect on skin whitening, collagen synthesis, and anti-aging, but has low oxidative stability during storage. Therefore, in this study, thermal and oxidation properties of L-ascorbic acid under various storage conditions (powder, aqueous phase, changes of temperature, UV-irradiation, and inflow of external air etc.) were investigated. And the storage stability of ingredient was validated in the double-spaced pouch by analysing oxidation properties under each storage conditions (powder phase and blended with essence). In oder to analyze the thermal properties, TGA, DSC, and FT-IR analysis were carried out and UV-visible spectrophotometer & redox titration were used in parallel for oxidation property analyses. From the result of experiment, L-ascorbic acid was oxidized fast when it contained lots of metallic ion, hydroxy ion in aqueous solution under high temperature, UV-irradiation & inflow external air, whereas it was not oxidized for a long time when it was stored as pure powder although it has same condition as heating up, UV-irradiation & inflow external air. Based on this result, retention period of cosmetics which is using L-ascorbic acid, less stable material in oxidation can be innovatively increased when using double-spaced pouch that is designed and produced for separating storage of active ingredients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.849-853
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• 2000

This study was examined for antibacterial effect of various molecular weight of chitosan against spoilage bacteria in emulsion sausage. Four different kinds of chitosan, molecular weights (M.W.) of 1 kDa, 5 kDa, 30 kDa and 120 kDa, wee used. The more molecular weight of chitosan is high, the more storage property of sausage is good during storage at $30^{\circ}C$. Storage properties of sausages between added 0.5% of M.W. 120 kDa chitosan and 150 ppm of sodium nitrite were about the same. Effect of growth-inhibitory of spoilage bacteria was not detected 0.2% of M.W. 1kDa chitosan 0.2% of M.W. 5kDa chitosan have growth-inhibitory effect over 80% against only 3 strains among bacteria isolated from spoiled emulsion sausage. But, 0.2% of M.W. 30 kDa chitosan have growth-inhibitory effect of 80% against all strains of bacteria related to spoilage of emulsion sausage, except S. typhimurium, Especially, 0.2% of M.W. 120 kDa chitosan inhibited over 80% growth against all strains used in this study. The antibacterial activity was increased with their molecular weight.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.4
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• pp.515-524
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• 1998

The purpose of this study was to evaluate the thermal properties of ceramics coated nylon fabrics by determining far infra-red emissive properties, heat storage/release and thermal insulation. Far IR emissivity and emissive power were measured for 7~ 140n at 50'C . Three types of ceramics such as cordierite with $\alpha$-alumina, a-alumina with titanium oxide and a-alumina were chosen as specimens. Cordierite with $\alpha$-alumina was chosen to treat on the fabrics due to the good emissive properties on the fabrics. Add-ons and contents of ceramics were analyzed for ceramics and/or polyurethane coated fabrics. For the physical properties, thickness and air permeability were measured. Results showed a difference in the emissive property between ceramics themselves and ceramics coated fabrics. In the ambient temperature, there was no diffenence in emissivity among the different ceramics contents. Thermography showed that when the fabric was heated with the light, surface mean temperatures of fabrics were increased as the contents of ceramics increased, and the heat storage property was confirmed. In case of same thickness and air permeability, the thermal insulation value increased as the contents of ceramics increased because of increasing heat storage and Far IR reflectivity. So there were absorption and heat storage of ceramics for Far IR from human and reflection to human between ceramics coated fabrics and human.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.4
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• pp.370-378
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• 2004

The purpose of this study was to investigate the effect of added nutriprotein and rice powder as a plasticizer on physicohemical property, texture property of Backsulgi. In the physicochemical property, the content of proximate composition of nutriprotein was measured as 6.1% of moisture, 3.6% of carbohydrate, 84.3% of crude protein, 0.6% of crude lipid, 5.4% of ash. The raw material of rice powder was measured as 9.6% of moisture, 83.7% of carbohydrate, 6.0% of crude protein, 0.4% of crude lipid, 0.3% of ash. Swelling power and pore ratio of the control were 78.53% and 72.42%, and tended to increase as the amounts of nutriprotein and plastic rice powder increased. Aging by Avrami eguation retarded in Backsulgi added 10% plastic rice powder than rice powder Backsulgi. All the samples added 2, 4, 6, and 8% nutriprotein at the temperatures of 20 were more effective than others on aging. In texture properties, cohesiveness and springiness were not significantly changed by adding nutriprotein and not significantly changed during the storage period in all samples. Hardness and gumminess decreased by adding 2∼8% nutriprotein and increased during the storage period in all samples. Springiness and gumminess decreased by adding 40% plastic rice powder and increased during the storage period in all sample. Cohesiveness and hardness decreased by the increase of plastic rice powder. The texture characteristics by rheometer showed that Backsulgi with nutriprotein and plastic rice powder exhibited lower in hardness than the control, indicating that nutriprotein and plastic rice powder were effective in retarding retrogradation, which is better when storage time became longer.

• Journal of Biosystems Engineering
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• v.29 no.4
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• pp.293-300
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• 2004

In order to solve the shortage of roughage supply for dairy farm in Korea, the mechanized model system for the production of winter cereal wrap silage in the fellow paddy field was developed in the previous studies. In this study, storage properties after long term storing of the winter cereal wrap silage were investigated. Also, the qualities of the wrap silage which was stored during 4 months were evaluated by sensory testings, analyzing chemical properties(moisture content, pH and organic acids) and investigating the increase of feeding value. The result of this study were summarized as follows; 1. After 300 hours storage, the acid level of the silage decreased slowly to 4.6 -4.8 pH. Also, the temperature was stabilized around 27-28$^{\circ}C$. The silage having below 5.0 pH is a desirable level for the most of good silage. 2. According to the sensory test and chemical property analyzation it was evaluated as the first class silage like a com silage. 3. Also, when the wrap silage are fed to the cattle, the cattle produced milk more 25% than that of conventional feed. 4. As an overall conclusion, winter cereal wrap silage in the fallow paddy field cm be one of the major roughage source in replacement of com and other conventional silage to dairy cattle in Korea.

• Applied Biological Chemistry
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• v.36 no.3
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• pp.146-153
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• 1993

The changes in water uptake rate, cooking property, color of rice grain, gelatinization property of milled rice during storage were studied. The water uptake rate constant of milled rice during storage at $4{\sim}30^{\circ}C$ for 3 months decreased, which was more pronounced at elevated storage temperatures. The activation energy of water uptake was different below and above $25^{\circ}C$ of storage temperature. The activation energy after storage for 3 months below and above $25^{\circ}C$ was 608 and 1269 cal/mole, respectively. The rice grain became harder and the cooking time was prolonged by $3{\sim}8$ minutes upon storage. The cooking rate constant was linearly decreased as a function of storage time. The activation energy of cooking after 1 month of storage was 235 cal/mole, which was increased by 1.7 times after storage of 1.5 months and thereafter by 1.2 times with the increase of 0.5 month. There were no significant changes in color of milled rice grains during storage at $4^{\circ}C$, but the increase of b value was observed at higher temperatures. The Initial pasting temperature of rice flour remained essentially unchanged during storage, but the peak viscosity consistently increased with the increase of storage time and temperature. The gelatinization temperature of rice flour by differential scanning calorimetry was not changed but enthalpy of gelatinization was decreased during storage.