• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.420-427
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• 2014

The physical and mechanical properties of sawdust-rice husk mixed ceramic were investigated with rice husk mixing ratios. The mixed ceramic board was produced with carbonization and resin impregnated sawdust-rice husk board at high temperature. At the same percentage of resin impregnation condition, density and bending strength of the mixed ceramic board increased with increasing the mixing rates of rice husk, whereas weight loss of the ceramic boards decreased. At the same temperature condition for the carbonization of resin impregnated sawdust-rice husk board, the density and bending strength were the highest with 40% of rice husk mixing ratio.

• Journal of the Korean Wood Science and Technology
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• v.33 no.1 s.129
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• pp.29-37
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• 2005

The main objective of this research was conducted to evaluate the impacts on the thermoplastic polymer which is a matrix polymer and the rice husk flour (RHF) which is a reinforcing filler relative to the manufacturing temperature and time when bio-composites were manufactured. In order to evaluate the impacts on the rice husk flour relative to the manufacturing temperature, the rice husk flour was persevered for 10 minutes to 2 hours period at $220^{\circ}C$ temperature which was then added with the polypropylene (PP) and low-density polyethylene (LDPE) to complete the manufacturing process of the bio-composites and measure the corresponding mechanical properties. As preserving time increased at $220^{\circ}C$, the tensile and impact strength were decreased due to the thermal degradation of the main components within the rice husk flour. The thermogravimetric analysis (TGA) was used to measure weight loss caused by the actual manufacturing temperature and the result was that the thermoplastic polymer had not scarcely occurred weight change, but there had been increasing rate of weight loss relative to time for the rice husk flour and the bio-composites under the consistent temperature of $220^{\circ}C$ for 2 hour time period. Therefore, the proper manufacturing temperature and time settings are significantly important features in order to prevent the reduction of mechanical properties which were induced throughout the manufacturing process under the high manufacturing temperature.

• Journal of Nutrition and Health
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• v.10 no.3
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• pp.10-24
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• 1977

The effects of dietary cellulose to utilize the intake nutrients in the albino rats were investigated by the two consecutive experiments in this study. The author wanted to observe the effects of the age of animals and different level of dietary cellulose, high and low in the first experiment and the effects of dietary cellulose from three different sources, rice bran, vegetable and pure-cellulose at high level in the second experiment. The results were summarized as follows. (1) The obvious effect of dietary cellulose caused to increase feces weight. Consequently apparent digestibilities of intake nutrients in the diet decreased. It was noteworthy that fecal glucose excretion was significantly affected by cellulose intake. Since three nutrients, protein, fat and carbohydrate serve as energy sources in the body, this result can be interpreted to be lowered in the efficiency of energy utilization out of intake from the diet. (2) The nutrients loss due to dietary cellulose resulted in reduction of skeletal muscle and bone weights which lead eventually to affect in reduction of body weight. (3) The effects of dietary cellulose showed differently according to the amount of cellulose ingested, dietary nutrients composition, the kinds of dietary cellulose supplemented and the age of experimental animals. When the intake diet was proportionately imbalanced in three different energy sources, carbohydrate, fat and protein, the cellulose intake was adversely affected in the utilization of the nutrients in the body. Cellulose from rice bran decreased body weight gain, cellulose from vegetable maintained medium level in body weight and pure-cellulose increased body weight. Growing rats showed more sensitive effects of cellulose tolerance in the body than grown rats in every concerns of this experiment.

• Research in Plant Disease
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• v.9 no.2
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• pp.68-71
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• 2003

Correlation between rice yield loss and infection time of neck blast after panicle emergence was analyzed in paddy fields at Icheon in 1999 and 2000. As the neck blast occurred at early heading stage, the yield loss of a early maturity variety, Jinmibyeo, ranged from 83.9% to 81.6%, while it ranged from 44.3% to 33.1% when the disease developed 30 days after heading. The regression equations of yield loss(y) caused by the neck blast infection time(x) in Jinmibyeo were y =1.2717x + 79.523(R2 = 0.9487) and y = 1.6872x + 74.545(R2 = 0.7993) in 1999 and 2000. In a mid-lately maturity variety, Chucheongbyeo, yield loss ranged from 64.9% to 47.8% when the disease developed at early heading stage. While it ranged from 29.1% to 8.9% when the disease occurred 40 days after heading. The regression equations of yield loss caused by the disease in Chucheongbyeo were y= 1.2717x + 79.523($R^2$ = 0.9487) and y = 1.6872x + 74.545(($R^2$ = 0.7993) in 1999 and 2000. Weights of 1,000 rice grains of Jinmibyeo and Chucheongbyeo were also drastically decreased to 38.3% and 57.3%, respectively, compared to healthy control when the disease occurred at early heading stage. However, weights of the two cultivars were 87.6% and 92.9% compared to control when the disease developed after 40 days of heading. Results indicated that there is a highly negative correlation between rice yield loss and infection time of the neck blast.

• The Korean Journal of Community Living Science
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• v.26 no.3
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• pp.447-456
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• 2015

To develop functional bread and improve the quality of gluten-free bread, this study investigates the quality characteristics of gluten-free rice bread made from soft-type rice (Bodeurami) flour mixed with black rice at different levels (0%, 10%, 20%, 30%, and 40%, w/w). An increase in the mix level of black-rice flour increased the weight of rice bread but reduced its volume, baking loss, volume expansion, and specific volume. The results for Hunter's color value and texture measurements indicate that an increase in the content of black-rice flour reduced the L-value, the b-value, hardness, gumminess, and chewiness but increased the a-value, adhesiveness, and springiness. According to the sensory analysis, rice bread formulated with a mixture of soft-type rice flour (80%) and black-rice flour (20%) showed the highest scores in color, taste, texture, and overall preferences. With respect to flavor and appearance, bread samples with 20% and 30% black-rice flour were preferred to those with 0%, 10%, and 40% black-rice flour. These results suggest that gluten-free rice bread mixed with wet-milling rice flour and black-rice flour can be used to develop functional and gluten-free bread.

• Food Engineering Progress
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• v.21 no.4
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• pp.332-340
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• 2017

This study investigated the changes in the physicochemical properties of soybean sprout, radish, and pork loin during frozen Bibimbab production. The qualities of soybean sprout were affected by the blanching, thawing, and cooking processes, with the blanching process particularly regarded as an important process to attribute the overall quality of the soybean sprouts in the final product. High weight loss of radish was found in the thawing and cooking processes, while the weight loss was relatively lower than that of soybean sprout. However, mixing with hot rice can be attributed for the steep decrease in shear force of the radish. For pork meat, normally thermal treatment such as mixing with hot rice and cooking manifested quality deterioration. Based on the results, mixing process appeared to be the most important process which affected the final quality of the materials. To improve the quality of final frozen Bibimbab, therefore, it was recommended to freeze the food ingredient separately from rice prior to packaging, which warranted the follow up exploration.

• Journal of the Korean Dietetic Association
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• v.15 no.2
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• pp.179-187
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• 2009

In this study, we examined whether the glycemic index (GI) values of boiled white rice (GI=86) and boiled white rice mixed with grains (GI=58) could influence the total energy intake and satiety rate of a rice-based diet. Thirty adult females participated in this study, in which they ate boiled white rice, or boiled white rice mixed with grains, along with side dishes for lunch, and then ate the same white rice diet for dinner in the lab once a week for 2 weeks. There was no significant difference in the visual analogue scales for taste between the two diets. Although there were no differences between the subjects' energy intakes for side dishes, the total energy consumed from the boiled white rice mixed with grains diet (520.5 kcal) was significantly (p<0.001) lower than that consumed from the boiled white rice diet (560.2 kcal). For dinner, the subjects consumed significantly (p<0.001) lower calories when they had eaten the boiled white rice mixed with grains diet for lunch as compared to the boiled white rice diet. In addition, the subjects reported significantly (p<0.01, p<0.001) higher satiety rates after consuming the boiled white rice mixed with grains diet compared to the boiled white rice diet, despite consuming lower calories. In conclusion, these results indicate that consuming low GI rice such as boiled white rice mixed with grains substituted for boiled white rice, may be a useful strategy for weight loss and weight management since individuals will consume less energy without experiencing a reduction in satiety.

• Korean journal of applied entomology
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• v.23 no.3 s.60
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• pp.153-157
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• 1984

The present work was designed to study the yield loss on rice at different appearance days of hopperburn caused by the brown planthopper(BPH), Nilaparvata lugens Stal, when rice plants were infested with BPH on booting and heading stages. Dead plants were colleted from 23 days after heading stage with intervals of 5 days. Yield losses by the initation of BPH infestation was greater at tooting than at heading stage. Compared to the uninfested plot, there was a reduction in 1,000 grain weight and filled grain percentage at both stages. Positive relationship was observed between rice yield(Y) and the number of days from heading to the appearance of the hopper-burn. Regression equations calculated were; for BPH feeding from booting $\hat{Y}(g)=10.145X-16.374(r=0.9726^{**})$, and for BPH feeding from heading $\hat{Y}(g)=9.792X+26.936(r=0.8850^{**})$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.1
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• pp.17-24
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• 2016

Drought caused by global climate change is one of serious problems for rice cultivation. However, it was little reported the impact of drought on rice cultivation in Korea. In here, to assess impact of drought on rice varieties in Korean climate condition, growth characteristics and yield components of rice were compared on irrigated and partially irrigated rice paddy field. First, we have chosen 11 rice varieties including 'Saeilmi' and 'Shindongjin' which are widely cultivated in Korea. For partially irrigated rice paddy treatment, we have withheld irrigation from 25 days after transplanting and water supply was totally dependent on rainfall for rice cultivation. When we examined early plant height and tiller number of these varieties on partially irrigated rice paddy were reduced 1.6% to 18.4% and 10.4% to 33.1%, respectively, and these reduction rate were highly correlated with yield loss in our experimental conditions. Among rice yield components, panicle number was decreased 10.5% to 30.1% according to rice varieties and reduced panicle number was highly correlated with yield loss. Grain number per panicle, grain filling rate and 1,000 seeds weight did not have correlation with yield loss of rice varieties. These result means that growth stage, especially the tillering stage, is seriously affected by drought on rice cultivation in Korea. And we suggest that 'Saeilmi', 'Ilmi' and 'Ilpum' are good for rice cultivation on drought prone rice field in Korea.

• Korean Journal of Community Nutrition
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• v.28 no.2
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• pp.141-159
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• 2023

Objectives: This study aimed to determine whether a mobile health (mhealth) intervention is effective in reducing weight and changing dietary behavior among employees with overweight and obesity. The study also investigated whether engagement with the intervention affected its effectiveness. Methods: The intervention involved the use of a dietary coaching app, a wearable device for monitoring physical activity and body composition, and a messenger app for communicating with participants and an intervention manager. A total of 235 employees were recruited for a 12-week intervention from eight workplaces in Korea. Questionnaire surveys, anthropometric measurements, and 24-h dietary recalls were conducted at baseline and after the intervention. Results: After the intervention, significant decreases in the mean body weight, body mass index, body fat percentage, and waist circumference were observed. Furthermore, the consumption frequencies of multigrain rice and legumes significantly increased, whereas those of pork belly, instant noodles, processed meat, carbonated beverages, and fast food significantly decreased compared with those at baseline. The mean dietary intake of energy and most nutrients also decreased after the intervention. When the participants were categorized into three groups according to their engagement level, significant differences in anthropometric data, dietary behaviors, and energy intake were observed following the intervention, although there were no differences at baseline, indicating that higher engagement level led to greater improvements in weight loss and dietary behavior. Conclusions: The intervention had positive effects on weight loss and dietary behavior changes, particularly among employees with higher engagement levels. These results indicate the importance of increasing the level of engagement in the intervention to enhance its effectiveness. The mhealth intervention is a promising model for health promotion for busy workers with limited time.