• Journal of Biosystems Engineering
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• v.24 no.4
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• pp.317-324
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• 1999

This study was conducted to decide several design criterion for clean-washed rice processing system development. A Computer simulation was used to predict and analyze the mass balances and moisture changes of the process of clean-washed rice processing system. The following results were obtained from this study. 1. In order to attain the processing capacity of 1,000kg/h of the clean-washed rice processing system, that of the system was designed as 1,400kg/h which was based on the safety factor of 40% and handling capability of mass variations occurred during processing. 2. It was analyzed that the proper time required for aqueous cleaning process should be within one minute. 2. It was analyzed that the proper time required for aqueous cleaning process should be within one minute. 3. The final moisture content of clean-washed rice was controlled being 15%(w.b.) for the sake of safe storage. 4. It was proven that the optimum drying time was three minutes for the clean-washed rice dried by a rotary dryer.

• The Korean Journal of Ecology
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• v.20 no.5
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• pp.375-384
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• 1997

The effects of three different irrigating water qualities(clean water, life sewage and animal sewage) on the pattern of arthropod communities in the rice fields were investigated at Banwol, Kyonggi-do, mid-western part of Korea from 1994 to 1996. The total density of arthropod was highest in the rice field which was irrigated with clean water(clean water field), and the arthropod community was mainly composed of aphids and collembolans. Each functional group was found in the order of 'pests>non-pests>natural enemies' in its density. The dominant taxa in the pest group were aphids, planthoppers(Delphacidae), leafhoppers(Cicadelidae) and rice water weevil(L. oryzophilus). In the non-pest group collembolans, non-biting midges and dipterans were main arthropods, and in the natural enemy group Araneae was the dominant taxon. In the early growth stage of rice plant the dominant functional group was pests, and in the mid growth stage both the pest and the natural enemy group became dominant. But in the late growth stage none of the functional group was dominant over the other functional groups. The densities of spiders were much more higher in the clean water field than in the other fields. And through all the growth stages of rice plants the density of spiders in clean water field kept increase in contrast to the others. The species composition of spiders in the life sewage field was similar to that in the animal sewage field, but in the clean water field it was different from the other two fields.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.878-885
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• 1996

The brown rice drying is effective for energy saving and cost reduction. However, deterioration after drying is one problem, because the skin damage occurs during the drying. So, the measures to preserve the quality has been investigated. One of major quality deteriorations is the oxidation of fat which is contained in the bran layer. So, milling should be carried out to remove the fat as soon as possible after brown rice drying. And the low temperature storage is also worth to be examined for prevention of oxidation. The effect of skin damage on the increase of fat oxidation was clarified. For the grain of skin damage, the increased of fatty acid vaule was remarkable after 70 days elapsed from occurrence of skin damage even in $15\;^{\circ}C$ condition. Therefore it is impossible to keep grain as brown rice form after brown rice drying. For the clean rice and excessively milled rice, the quality can be preserved even in high temperature of $30\;^{\circ}C$. Therefore the brown rice drying can b applied practically using the clean rice technique.

• Journal of Biosystems Engineering
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• v.29 no.4
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• pp.307-316
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• 2004

This study was conducted to develop a coating system for producing clean enriched rice. The nutritional components of such as brown rice, white rice, clean white rice, enriched rice of US, black rice of China, and rice with perfume of China, were analyzed and compared. Total protein lipid md minerals in brown rice were higher than those in the other rices. A nutrition premix with lysine, thiamine, niacine, calcium lactate, ferrous lactate, and rice starch was made for enriching white rice. A coating device consisted of a tumbler, two spraying nozzles, a rice mixer, etc was developed with the capacity of 1 ton/h. And far-infrared dryers of batch and continuous types were developed to dry hygienically the wet enriched rice. The percentages of lysine, thiamine, amino acid nitride, and Ca and Fe of the enriched rice samples produced in this study were, respectively, 4, 3, 3. 2, and 10 times higher than those of white rice, respectively.

• Food Science and Preservation
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• v.23 no.4
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• pp.522-529
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• 2016

Clean rice is useful to save time and labor force against washing rice in the household. Nevertheless the quality characteristics of the rice were not established well since the quality characteristics of the rice depend on types of the processing system. The aims of the current study were to understand the quality characteristics of clean rice prepared from the dry, semi-dry, and wet types of processing systems, and to suggest the appropriate processing system for production of clean rice. Here, we found that the quality of clean rice was improved with the increasing whiteness of rice by the dry type, although the whiteness of rice should be below 42 to satisfy 16.0 NTU of the turbidity for higher head rice ratio. Also, both the semi-dry and wet type systems showed higher ratio of head rice than the dry type system at below 16.0 NTU of the turbidity. These results imply that the wet type is more suitable for the place where rice is consumed fast, and the semi-dry type is more proper for long term storage of rice.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.12a
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• pp.371-377
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• 1999

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.723-728
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• 2003

The sensory characteristics of cream soup containing 0, 25, 50, 75 and 100％ rice flour were investigated in order to develop a new processed food using rice. The Hunter L(lightness) value increased with the amount of rice flour, while the a(redness) value and b(yellowness) value decreased, significantly. The viscosity of rice cream soup significantly decreased with the increasing amount of rice flour. Based on the sensory evaluation, the cream soup samples with larger rice flour component showed a higher clean taste score, while those with the least rice flour resulted in higher darkness, viscosity, greasy taste, md softness. The overall acceptance was the highest in the cream soup with 75％ and 100％ rice flour. In terms of the color and viscosity, good correlations were observed between the sensory evaluation and the objective analysis. The overall acceptance showed a significant positive correlation with a clean taste, while there was a negative correlation with a greasy taste and the viscosity measured by a viscometer.

• Korean Chemical Engineering Research
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• v.56 no.4
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• pp.547-554
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• 2018

Torrefaction is the promising process of pretreating biomass materials to increase the quality of their energy, especially to upgrade the materials' grindability so that it is suitable for a commercial pulverizer machine. In this study, torrefaction of oak, bamboo, oil palm trunk, and rice husk was carried out under different torrefaction temperatures ($300^{\circ}C$, $330^{\circ}C$, and $350^{\circ}C$) and different torrefaction residence times (30, 45, and 60 minutes). Complete characterization of the torrefied biomass, including proximate analysis, calorific value, thermogravimetric analysis, mass yield, energy yield, and grindability properties (Hardgrove Grindability Index) was carried out. Increasing the torrefaction temperature and residence time significantly improved the calorific value, energy density (by reducing the product mass), and grindability of the product. Furthermore, for commercial purposes, the torrefaction conditions that produced the desired grindability properties of the torrefied product were $330^{\circ}C-30minutes$ and $300^{\circ}-45minutes$, and the latter condition produced a higher energy yield for bamboo, oil palm trunk, and rice husk; however, torrefaction of oak did not achieve the targeted grindability property values.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.02a
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• pp.357-362
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• 2000

• Journal of Environmental Science International
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• v.14 no.9
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• pp.873-879
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• 2005

This study was investigate to evaluate the phosphate uptake rate of green algae in relation to diurnal rhythm and algae control method. The phosphate uptake rates of Chlorella vulgaris and Ankistrodesmus convolutus increased in light period and decreased in dark period. On the contrary, those of Chlamydomonas sp. showed a peak in the late dark period. The differences among species in phosphate uptake in relation to diurnal rhythm were due to the severe competition among species and seemed to alleviate the competition for nutrient supplies. The compound of CellCaSi, Ca and Fe showed the effective removal of the phosphorus. The extracts from rice and barley straw exhibited a significant effect on the growth inhibition of Microcystis aeruginosa.