• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.569-577
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• 2019

The current experiment was conducted to compare nutrient utilization in the aged laying hens with different eggshell strengths or different intensities of brown eggshell color. Two metabolic trials with 96-week-old Hy-Line Brown laying hens were conducted. Twelve hens with a strong eggshell strength (SES) and 12 hens with a weak eggshell strength (WES) were selected and used in the first experiment, whereas 12 hens with dark brown eggshells (DBE) and 12 hens with light brown eggshells (LBE) were selected and used in the second experiment. All hens were fed a common commercial layer diet. Diets included chromic oxide as an indigestible marker to determine the apparent total tract retention (ATTR) of the gross energy (GE), dry matter, acid-hydrolyzed ether extract, nitrogen, neutral detergent fiber, acid detergent fiber, ash, and minerals. The results indicate that the ATTR of Ca in the aged laying hens with SES (59.7%) was greater (p < 0.05) than in the aged laying hens with WES (48.6%). However, the ATTR of the GE and other nutrients was not different between the hens with SES or WES. There were no differences in the ATTR of GE and nutrients between the hens with DBE or LBE. In conclusion, aged laying hens with SES have a greater ability to utilize dietary Ca than those with WES, indicating that the extent of dietary Ca utilization determines the eggshell strength of aged laying hens. However, nutrient utilization in diets may have little impact on eggshell brown coloration in aged laying hens.

• Korean Journal of Construction Engineering and Management
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• v.16 no.5
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• pp.105-113
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• 2015

In order to evaluate the energy performance of buildings, it is important to determine reliable information of energy utilization during operating phase. It is also required to establish the database which have the amounts of population deducted by objective filtering and analysis. In this study, all energy sources were applied to evaluate synthetically the energy performance of Multi-Family Housings(MFH) using district heating and the amounts of population were obtained sufficiently through data searching in Seoul and neighbor cities. Finally the database of source energy utilization and $CO_2$ emission in 325 MFH complexes were established through cross validation between data sources and statistical analysis. Additionally, further ideas have been proposed to improve existing MFH Management Information System.

• KSBB Journal
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• v.19 no.4
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• pp.257-262
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• 2004

Recently, there is a growing interest in microalgae and the use of microalgae focused on the production of various high value metabolite used in food, pharmaceuticals and cosmetics. The key limiting factor in high density algal cultivation is the light and algal growth is defined by light intensity and light penetration depth into the culture medium. The effect of light with various light paths, S/V ratios, light intensities, and 50% duty cycle on the growth of microalgae was examined to enhance microalgal biomass productivity and photosynthetic efficiency. We confirmed that the utilization of efficient light energy was obtained from 4 cm of diameter, 57.6% of S/V ratio, 62 ${\mu}$mol/㎡/s of light intensity.

• Journal of Biosystems Engineering
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• v.43 no.2
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• pp.128-137
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• 2018

Purpose: This study was designed to elucidate the energy-utilization patterns for five methods of robo production. Methods: Robo (fried melon cake) was produced using five different methods, and the energy used for each unit operation was calculated using standard equations. The sensory attributes of the products were determined by panelists. Data were analyzed using descriptive analysis and analysis of variance at p < 0.05. Results: The energy demands for processing 2.84 kg of melon seed into robo (fried melon cake) using processes 1 (traditional method), 2, 3, 4, and 5 (improved methods) were 50,599.5, 21,793.6, 20,379.7, 21,842.9, and 20,429.3 kJ, respectively. These are equivalent to energy intensities of 1,7816.7, 7,673.8, 7,175.9, 7,691.2, and 7,193.4 kJ/kg, respectively. For the traditional process, the frying operation consumed the highest energy (21,412.0 kJ), and the mixing operation consumed the lowest energy (675.0 kJ). For the semi-mechanized processes, the molding operation consumed the highest energy (6,120.0 kJ), and the dry milling consumed the lowest energy (14.4 kJ). Conclusions: The energy-consumption patterns were functions of the type of unit operation, the technology involved in the operations, and the size of the equipment used in the whole processing operation. Robo produced via the milling of dried melon seed before oil expression was rated highest with regard to the aroma and taste quality, as well as the overall acceptability of the sensory evaluation, and required the lowest energy consumption. Full mechanization of the process line has potential for further reduction of the energy demand.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.5
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• pp.295-302
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• 2002

To understand the utilization property of light energy, Synechococcus sp. MA19, a poly-${\beta}$-hydroxybutyrate (PHB) producer, was cultivated at the different incident light intensities of 15.3, 50.0 and 78.2 W/$m^2$ using media with and without phosphate. From the results of metabolic flux analysis, it was found that the cell yield based on ATP synthesis was estimated as $3.5{\times}10^{-3}$ kg-biomass/mol-ATP in these cultures. Under the examined conditions, there were no significant differences in the efficiency of light energy conversion to chemical energies estimated as ATP synthesis and reducing potential (NADH + NADPH) formation whether the PHB synthesis took place or not. The energy converted from light to ATP was kept relatively high around the energy absorbed by the cells of $2.5-3.0{\times}10^{6} J\;h^{-1}\;kg^{-1}$, whereas the energy of reducing potential was hardly changed in the examined range of the energy absorbed by the cells.