• Tribology and Lubricants
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• v.25 no.4
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• pp.236-242
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• 2009

Oil viscosity is one of the important parameters for machinery condition monitoring. Basically, it is expressed as kinematic viscosity measured by capillary flow and dynamic or absolute viscosity measured by rotary shear viscometry. Recently, acoustic wave techniques appear in the market, measuring viscosity as the product of dynamic viscosity and density. For Newtonian fluids, knowledge of density allows conversion from one viscosity parameter to the other at a specific shear rate and temperature. In this work, oil samples with different chain lengths of viscosity index (VI) improvers and concentrations were examined by different viscometric techniques. Results showed that acoustic viscosity measurements give misleading results for oil samples with high molecular weight VI improvers and at low temperatures ${\leq}40^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.177-182
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• 2011

This study was designed to evaluate the effect of Yukwa prepared by addition of green tea powder on change of lipid composition and body weight in mouse model. Mice were fed with Yukwa containing the five different types of green tea powders such as Bucho-cha, Okro-cha, Yongjeong-cha, Oolong-cha and Hong-cha with a normal diet. Body weight changes of Yukwa fed mice were measured once in a week for seven weeks. After seven weeks, mice were sacrificed and serum and tissues were collected for the following: adipose tissue weight, liver morphology, adipose tissue size and cholesterol content. The Yukwa combination with green tea fed mice reduced all the parameters compared to Yukwa alone fed mice. In conclusion combination with green tea showed reducing effect of hypocholesterolemia, which suggests the possibility of application to green tea as a food ingredient.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.1
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• pp.25-28
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• 2000

A comprehensive study on daily pupal weight loss due to histolysis and histgenesis in Bombyx mori Linn., has been undertaken. The percentag of pupal weight loss in the male pupa is higher than the female, conforming that the female pupa require more energy in the form of less pupal weight loss for ovipositional activities. The regression equation clearly shows higher percentage loss of daily pupal weight in male than female with respect to age and, this is also evident from the slope of the regression line. Moreover, analysis of the coefficient of correlation shows that the weight loss of pupa is directly correlated with the age rather than climatic parameters under which the pupa dwells.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.831-835
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• 2007

Energy Saving is one of worldwide emerging issues. These days, applicable techniques of railway vehicle's regenerative energy are investigating in worldwide railway industries. Energy saving methods are "Downsizing energy loss" and "Re-utilizing kinetic energy". Useful plans for Downsizing energy loss are "adjusting operation table" and "optimizing running pattern". Furthermore, regenerative energy that is produced with decreasing speed and stoping, is an important element with reducing vehicle's weight, raising equipment 's efficiency, decreasing running resistance and re-configurating running pattern. Sustainable energy storage mass : Flywheel, EDLC(electrical double layer capacitor) and Secondary battery are applied in overseas, but these cases are not reported within the country. This research is reported for problems and economical validity that comes from by installing sustainable regenerative energy storage system in korean railway industries.

• International Journal of Ocean System Engineering
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• v.3 no.3
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• pp.131-135
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• 2013

We construct the fundamental fields for 3-D arbitrarily shaped plane cracks in by differentiating with respect to a parameter of the crack. As an application of these fundamental fields, the total elastic energy release rate in combined mode cracking is computed.

• Journal of Animal Science and Technology
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• v.61 no.6
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• pp.305-312
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• 2019

This study was carried out to investigate the effects of dietary energy levels on growth performance, blood parameter, and intestinal morphology of Pekin ducks in low temperature. A total of 500, 21-d-old Pekin ducks (initial BW = 1,089 ± 5.21 g) were evenly assigned to five dietary treatments (2,950, 3,000, 3,050, 3,100, or 3,150 kcal AME/kg, calculated on an as-is basis) with four replicates (pens) for each treatment (25 ducks per pen). During the experiment, hens were provided with feed and water ad libitum. Overall, increasing dietary energy levels corresponded to an increase of final body weight and body weight gain (linear, p < 0.01). Feed intake decreased (linear, p < 0.01) and feed conversion ratio increased (linear, p < 0.01) with increasing levels of energy. There were no significant differences (p < 0.05) in the level of leukocytes between groups. However, heterophils decreased (quadratic, p < 0.05) and lymphocytes increased (linear, p < 0.01) as inclusion of dietary energy levels increased. The H/L ratio increased (linear, p < 0.01) with increasing dietary energy levels while serum corticosterone levels decreased at overall experimental periods. Triglycerides increased (linear and quadratic, p < 0.05) with increasing dietary energy levels. There were no significant changes in villus height or crypt depth of the jejunum at overall experimental. In conclusion, increasing concentrations of dietary energy levels up to 2,950-3,150 kcal/kg in diet. Additionally, 3,150 kcal/kg dietary energy had been revealed more beneficial and could be practiced as protective management for the Pekin ducks reared under low ambient temperature (8℃ to 10℃).

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1305-1309
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• 2009

This study evaluated the effects of $\gamma$-irradiation on immunomodulating properties and structural changes of ${\beta}$-glucan. ${\beta}$-Glucan solutions (10 mg/mL) were ${\gamma}$-irradiated at 10, 30, and 50 kGy. Splenocyte proliferation and cytokine (interferon-${\gamma}$ and interlukin-2) productions by ${\gamma}$-irradiated ${\beta}$-glucan were evaluated in in vivo and in vitro, and structural changes of ${\beta}$-glucan were also determined after ${\gamma}$-irradiation. ${\gamma}$-Irradiation on ${\beta}$-glucan at 50 kGy enhanced splenocyte proliferation and cytokine productions, (p<0.05) and cleft glycosidic bonds of ${\beta}$-glucan resulting in lower the molecular weight. These results indicate that the use of ${\gamma}$-irradiation on ${\beta}$-glucan may be useful for improving its immunological activity by lowering the molecular weight of ${\beta}$-glucan.

• Journal of Biosystems Engineering
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• v.9 no.2
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• pp.65-73
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• 1984

While most of researches on the performance of high temperature grain dryer have dealt mainly with improving dryer capacity and drying speed during the last twenty years, energy efficiency, in fact, has not been emphasized. Current fuel supplies and energy cost have shifted the emphasis to reducing the energy consumption for grain drying while maintaining dryer capacity and grain quality. Since the energy input for drying is relatively large, the recovery and reuse of at least part of the exhaust energy can significantly reduce the total energy consumption in existing drying systems. Unilization of exhaust heat in grain dryer either through direct recycling or by a thermal coupling in heat exchanger have been subject of a number of investigators. However, very seldom research in Korea has been done in this area. Three drying tests(non-recycling, 0.22 recycle ratio, and 0.76 recycle ratio)were performed to investigate the thermal efficiency and heat loss factors of continuous flow type dryer, and to analyze the effect of recycle ratio (weight of exhaust air recycled/total weight of input air) on the energy requriements for rough rice drying. The test results showed that when the exhaust air was not recycled, the energy lost from furnace was 15.3 percent of input fuel energy, and latent and sensible heat of exhaust air were 61.4 percent and 11.2 percent respectively. The heat which was required in raising grain temperature and stored in dryer was relatively small. As the recycle ratio of exhaust air was increased, the drying rate was suddenly decreased, and thermal efficiency of the kerosene burner was also decreased. Drying test with 0.76 recycle ratio resulted in 12.4% increase in fuel consumption, and 38.4% increase in electric power consumption as compared to the non-recycled drying test. Drying test of 0.22 recycle ratio resulted in 6.8% saving in total energy consumption, 8.0% reduction in fuel consumption, and 2.5% increase in electric power consumption as compared to the non-recycled drying test.

• Korean Journal of Poultry Science
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• v.14 no.1
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• pp.1-8
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• 1987

Three experiments were conducted to investigate effects of dietary energy and protein levels on performance of laying hens. A total of 360 hens each of 352-day old Manina Brown (Exp.1), 280-day old Brown Warren (Exp.2) or 3174ay old Brown Warren (Exp.3) was divided into 20 pens of 18 birds. Each pen was assigned to one of the four dietary treatments with 5 replications according to a 2${\times}$2 factorial design, consisting of all possible cominations of two levels of metabolizable energy (2,500 and 2,800 kcal/kg of diet) and two levels of crude Protein (13 and 16%). All hens were housed two birds per cage. Exp.1 and 2 were conducted for four weeks and hens were fed experimental diets ad libitum, and Exp.3 lasted two weeks and feed consumption was restricted to 130g/hen/day. In Exp.1 and 2, increasing either energy or protein level in the diet numberically improved egg production. However, in Exp. 3, where feed consumption was restricted, egg Production was affected significantly 〈0.05) by the energy levies and numerically by the protein levels. Neither protein nor energy level influenced egg weight in Exp. 1 and 2, but in Exp. 3 the higher level of energy improved egg weight numerically, In all three experiments increasing either protein or energy level increased egg mass. Higher levels of either protein and energy tended to decrease feed consumption and improve feed conversion rate numerically. It should also be noted that the higher level of energy improved egg mass produced per unit intake of protein and the higher level of Protein improved egg mass produced per unit intake of energy.

• Journal of Nutrition and Health
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• v.26 no.4
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• pp.390-404
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• 1993

The purpose of this paper is to determine the percentage of body fat by measurement of skin-fold thickness of the triceps and the subscapular area to investigate the relationship between the daily energy intake and expenditure among obese women and nonobese women based on the percentage of body fat and age. This survey included 422 females in Cheju. 1) The age distribution of the 422 females surveyed was : 26.8% were in their 20's, 20.6% in their 30's, 21.3% in their 40's, 19.0% in their 50's and 12.3% were above 60 years of age. The 422 females consisted consisted of 78% housewives, 12.8% college student and 9.2% single working women. 2) The average height and weight of the surveyed women were respecitively 159.0$\pm$4.2cm and 56.0$\pm$7.2kg, the percentage of body fat of the surveyed women was 24.8$\pm$9.8%, and the BMI of those surveyed was 22.7$\pm$2.7. If higher than 30% body fat was defined as being obese, 15.6% of the surveyed women were assessed to be obese. 3) Total daily food consumption and energy intake of the group of women aged 60 and older was significantly small. Food consumption and nutrient intake of obese women was greater than that of the nonobese group, but not significant. Carbohydrate intake of the obese group in their 40's was significantly higher than the nonobese group. Total food consumption, energy and carbohydrate intake of the obese group in their 50's was significantly higher than the nonobese group. Vegetable intake of the obese group in their 60's and older was significantly higher than the nonobese group. 4) The total time of physiological activity of women aged 60 and older was significantly higher than for the other age groups and the total work time was significantly lower. The total work time of women in their 20's was not lower than the other groups. Considering the low energy expenditure of physical activity for women in their 20's, they appeared to have light activity. However, there was not a significant difference in the physical activity time among middle aged women groups(from 30 to 50). The entire energy expenditure of the obese group was greater than the nonobese group. However, the energy expenditure per body weight in the obese group was significantly less than that of the nonobese group in terms of the basal metabolic rate in consideration of the fat free mass. 5) There was a positive correlation between the percentage of body fat and the factors of age, sleeping time, total time of physiological activity, housework time, time spent watching TV, energy expenditure, energy intake, carbohydrate and cereal consumption. On the other hand, the percentage of body fat was negatively correlated with energy expenditure per body weight based on the basal metabolic rate in consideration of the free mass.