• Applied Biological Chemistry
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• v.28 no.3
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• pp.167-173
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• 1985

Hot air drying characteristics of six year old cooked ginseng root at temperature ranges of $55{\sim}75^{\circ}C$ under 1.8m/sec air velocity and shrinkages accompained were investigated. Drying time to reach equilibrium moisture content of the root takes from 20 to 30 hours, depending on the subjected drying temperatures and root sizes. Drying curve shows that it has two or three falling stages and drying constant are continuously changed. Higher drying constant was observed both at early and late stages of drying. Shrinkage ratio of length, diameters, surface area and volume of the root were 13.0, 39.8, 47.7 and 68.5%, respectively, after 40 hours dry at $55^{\circ}C$. The most of shrinkage was observed at early drying stage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1604-1611
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• 2007

This study was conducted to investigate the quality characteristics of Jeolpyun prepared with different percentages of lotus leaf powder for 4 days. The moisture content of Jeolpyun without lotus leaf powder was 50.63% and those of Jeolpyun with the powder were $50.17{\sim}52.63%$ on 0 day; however, they did not show constant tendency during storage. Total cell counts of Jeolpyun with lotus leaf powder increased less than those of Jeolpyun without the powder during storage. As lotus leaf powder increased, L values of lotus leaf Jeolpyun significantly decreased and their a values significantly increased. As storage time increased, L values of lotus leaf Jeolpyun increased, and a and b values did not show constant tendency during storage. There was no difference between Jeolpyun with lotus leaf powder and Jeolpyun without the powder in hardness and chewiness on 0 day. As lotus leaf powder increased, the hardness and chewiness of lotus leaf Jeolpyun decreased after 1 day. The adhesiveness of 0% lotus leaf Jeolpyun significantly decreased after 2 days, and there was no difference in adhesiveness except for 3% lotus leaf Jeolpyun by 2 days. The springiness of 2% and 3% lotus leaf Jeolpyun was not significantly different for 4 days and the gumminess of all samples increased after 2 days. There was significant difference in cohesiveness between Jeolpyun with lotus leaf powder and Jeolpyun without on 0 day, but there was no great difference during storage. In the sensory evaluation, 2% lotus leaf Jeolpyun showed the highest preference scores; hence, 2% lotus leaf Jeolpyun prepared with 980 g rice flour, 20 g lotus leaf powder, 10 g salt and 360 g water was picked as the best.

• Structural Engineering and Mechanics
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• v.32 no.3
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• pp.429-445
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• 2009

Thermal stability of quasi-isotropic composite and polymeric structures is considered one of the most important criteria in predicting life span of building structures. The outdoor applications of these structures have raised some legitimate concerns about their durability including moisture resistance and thermal stability. Exposure of such quasi-isotropic composite/polymeric structures to various and severe climatic conditions such as heat flux and frigid climate would change the material behavior and thermal viability and may lead to the degradation of material properties and building durability. This paper presents an analytical model for the generalized problem. This model accommodates the non-linearity and the non-homogeneity of the internal heat generated within the structure and the changes, modification to the material constants, and the structural size. The paper also investigates the effect of the incorporation of the temperature and/or material constant sensitive internal heat generation with four encountered climatic conditions on thermal stability of infinite cylindrical quasi-isotropic composite/polymeric structures. This can eventually result in the failure of such structures. Detailed critical analyses for four case studies which consider the population of the internal heat generation, cylindrical size, material constants, and four different climatic conditions are carried out. For each case of the proposed boundary conditions, the critical thermal stability parameter is determined. The results of this paper indicate that the thermal stability parameter is critically dependent on the cylinder size, material constants/selection, the convective heat transfer coefficient, subjected heat flux and other constants accrued from the structure environment.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.850-854
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• 2012

This study is carried out in order to develop food materials for the promotion of rice consumption. In this study, we researched the physicochemical properties of extruded rice flour (ER) and gelatinization popped rice flour (GPR) by the extrusion process and by the popped method with milled rice and brown rice. The extrusion process used a couple of screw extruders. The extrusion parameter was kept constant at a feed moisture content of 25%, barrel temperature of $120^{\circ}C$ and screw speed of 400 rpm. GPR was prepared by batch popping machine after gelatinization of rice. In order to evaluate the physicochemical properties of ER and GPR, as well as the gelatinization rate, water soluble index (WSI), water adsorption index (WAI), DPPH radical scavenging activity and total dietary fiber content, the color value was carried out. The gelatinization rate was similar to 71.1~73.8%. Further, the results of WSI and WAI were increased at ER and GPR compared to the raw materials; ER was also higher than GPR. DPPH radical scavenging activity and total dietary fiber content showed a tendency to reduce after extrution and popping. As a result of the color value, the L value of ER decreased more than the raw materials, whereas GPR increased at a and b values.

• Current Research on Agriculture and Life Sciences
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• v.7
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• pp.175-184
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• 1989

Kinetics of ascorbic acid and browning that may use on the optimization of food dehydration were evaluated. Banana was chosen for this as the representative test material. We have described the destruction of ascorbic acid and browning as first and zero order reactions. The temperature dependence between two reactions were conducted with Arrhenius equation. Finally we have operated SPSS computer programs reapeatedly that we found very dose value of the parameter between result of ascorbic acid and browning. The attained Kinetic models were well prepared for the value of result experiments and the models may use on optimization for dehydration progress. Destruction rate of ascorbic acid and browning rate were low at initiation of progress, increased to show maximum at the low moisture on mid-progress and then decreased gradually. Freeze drying showed the most constant quality of product in this case.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.6 s.119
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• pp.39-53
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• 2007

Unlike conventional roof landscaping, where various kinds of plants and structures are employed, a grass roof is a roof on which herbaceous plants are grown in planting medium and which is not accessed or maintained, mainly because it doesn't have sufficient load capacity to support a regular roof garden. They are mostly built on existing roofs, whether flat slab or gabled. Planting on roofs has numerous advantages, such as creating a biotope, purifying urban air, adding moisture to the atmosphere, storing rain water, preventing flash floods, reducing energy use for heating and air conditioning, enhancing the urban landscape and providing relaxation to the city dwellers, not to mention the alleviation of global warming by absorbing $CO_2$. In addition to the general merits of roof planting, the grass roof has its own unique qualities. Only herbaceous species are planted on the roof, resulting in light weight which allows roofs of existing buildings to be planted without structural reinforcement. The species chosen are mostly short, tough perennials that don't need to be maintained. These conditions provide an ideal situation where massive planting can be done in urban areas where roofs are often the only and definitely the largest space available to be planted. If roofs are planted on a massive scale they can play a significant role in alleviating global warming, heat island effects and energy shortages. Despite the advantages of grass roofs, there are some problems. The most significant problem is the invasion of neighboring plants. They may be brought in with the planting medium, by birds or by wind. These plants have little aesthetic value comparing to the chosen species and are usually taller. Eventually they dominate and prevail over the original species. The intended planting design disappears and the roof comes to look wild. Since the primary value of a grass roof is ecological, a change in attitude towards what constitutes beauty on the roofscape is necessary. Instead of keeping the roof neat through constant maintenance, people must learn that the wild grass with bird's nests on their roof is more beautiful as it is.

• Journal of Energy Engineering
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• v.21 no.4
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• pp.373-377
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• 2012

Among the fossil fuels, the brown coal is a great deal of resources. However, it is hardly used due to the high moisture content and low calorific value. It has both the week points such as spontaneous combustion and high volatile content and the strong points such as the low-sulfur and low ash content. If we overcome these week points, the using amount of brown coal would be increased. Also, it is well known that biomass is one of the important primary renewable energy sources because of carbon neutral energy. Furthermore, the utilization of biomass has been more and more concerned with the depletion of fossil fuel sources as well as the global warming issues. Combustion and thermal decomposition of biomass is one of the more promising techniques among all alternatives proposed for the production of energy from biomass. In this study, combustion of brown coals and mushroom waste was done. Mass change of samples and emission of hydrocarbon components were measured. As the results, we obtained combustion rate constant. Also activation energy was calculated in char combustion step. Hydrocarbon components were more generated in low oxygen concentration than high. Emission amount of hydrocarbon components in mushroom waste was significantly increased comparing to brown coal.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.215-220
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• 1990

Effects of frying conditions on cooking properties of ramyon (deep-fried instant noodle) were investigated. The moisture content, which was decreased as the frying temperature $(140-160^{\circ}C)$ and time (30-70 sec) increased, was negatively correlated with lipid content. The weight gain was higher than volume gain at a given frying condition Weight or volume gain rate constant for ramyons fried at $140^{\circ}\;and\;150^{\circ}C$ increased with increase of frying time, but that for ramyon fried at $140^{\circ}\;and\;150^{\circ}C$ increased with increase of frying time, but that for ramyon fried at $160^{\circ}C$ showed opposite trend. The initial cooking rate decreased as the frying time was increased in all cases and as the frying temperature was elevated at a given frying time.

• Journal of Conservation Science
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• v.30 no.4
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• pp.467-480
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• 2014

This study was focused on measurement methods for stone cultural heritages by analyzing Ultrasonic (P-wave) velocity variations according to the water content and anisotropy of rocks. As a result of analyzing of rock properties, the water content and saturation degree were rapidly changed at the beginning of drying and then showed exponential curve which their rates of change gradually decreased. However, P-wave velocity and its rate of change maintained constant values after natural drying of 10 hours. Therefore, the ultrasonic measurement for stone cultural heritages should be performed after natural drying of 10 hours considering the weather and moisture conditions. In addition, the highest values of anisotropy coefficient exhibited in granite and limestone, and indirect method was insensitive to anisotropy compared to direct method. However, all rocks remained anisotropy by indirect method. Accordingly, ultrasonic measurement considering various directions is required. The research results will contribute to customized non-destructive testing and precise diagnosis for lithological characteristics of stone cultural heritage.

• Current Research on Agriculture and Life Sciences
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• v.8
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• pp.89-94
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• 1990

Respiration and soluble carbohydrates of stored mushrooms (Agaricus bisporus) were determined to be associated with physiological and biochemical changes induced by ionizing radiation treatment which was applied for extending the shelf-life. Immediately after gamma irradiation at 1 to 3 kGy, the respiratory rate of mushrooms increased linearly with increasing doses of irradiation, and then it normarized after 2 days of storage at $9{\pm}1^{\circ}C$ and $80{\pm}7%$ RH. In the nonirradiated mushrooms, the respiratory peak was observed at around 5 to 6 days after storage, while irradiation treatment not only reduced respiratory activities of stored mushrooms, but prolonged the peak development. Moisture content and dry matter of mushrooms packaged in a paper box and polyethylene film were relatively constant during the storage for 20 days and the reducing sugar contents decreased significantly after 5 days of storage(p<0.01). Free sugars of mushroom pilei, which consisted of mannitol, trehalose and glucose, also markedly decreased at the earlier part of the storage period and thereafter, 2 kGy irradiation resulted in the reduction of their changes.