• Asian-Australasian Journal of Animal Sciences
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• v.16 no.6
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• pp.903-909
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• 2003

For the last two decades, energy utilization of growing chicks has been studied more and more. This paper focuses on the energy utilization estimated by the metabolizable energy (ME) values and the efficiency at which ME is used for growth of chicks under various nutritional environment. Degree of saturation of dietary fats is responsible for nitrogen-corrected apparent metabolizable energy (AMEn) of fats. The effect of dietary fat sources on heat production depends on the kind of unsaturated fatty acids as well as the degree of saturation. Medium chain triglyceride shows lower AME and net energy than long chain triglyceride. Phytase as feed additives increases the AME values of the diet along with improvement of the phosphorous utilization. Ostriches have higher ability to metabolize the energy of fiber-rich foodstuffs than fowls. Their higher ability seems to be associated with fermentation of fiber in the hindgut. Proportions of macronutrients in the diets have influenced not only the gain of body protein and energy but also the oxidative phosphorylation of the chicken liver. Essential amino acids deficiency reduces ME/GE (energy metabolizability) little, if any. Growing chicks respond to a deficiency of single essential amino acids with the reduction of energy retained as protein and increased energy retained as fat. Thus, energy retention is proportional to ME intake despite deficiency, and efficiency of ME utilization is not affected by deficiency of amino acids. Effect of oral administration of clenbuterol, a beta-adrenergic agonist, on the utilization of ME varies with the dose of the agents. Although the heat production related to eating behavior has been estimated less than 5% of ME, tube-feeding diets decreases HI by about 30%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.05a
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• pp.9-14
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• 1996

The dependence of microstructural and optical properties of Ag-In-Sb-Te thin films on annealing heat-treatments was studied. It was found from the present work that the increase of reflectance after annealing heat-treatment is related with phase change of Ag-In-Sb-Te thin film from amorphous state to crystalline phases which involve Sb crystalline phase and AgInTe$_2$ stoichiometric phase. On the other hand, the reflectance is decreased after high temperature annealing (above 450$^{\circ}C$), due to the morphology .mange of film surface. For the purpose of practical application(erasable optical disk), we fabricated quadrilayered Ag-In-Sb-Te alloy disk, and annealed it with continuous laser beam. As result of this laser\ulcorner annealing treatment, we found that the increment of reflectance is 9.3% at 780nm wavelength. It might be considered that Ag-In-Sb-Te alloy optical disk is the big promising candidate for the erasable optical memory medium.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2966-2970
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• 2015

Recently, solar light power generation is widely extended by support policy to regeneration energy. However generation efficiency is decreased when solar module maintain higher than certain point temperature. Therefore, it is need to maintenance under certain point temperature. An method of solving this problem, this paper is developed geothermal exchanger for efficiency improvement of solar cell module. Geothermal exchanger consisted of heat absorber of solar cell module and heat conductor and radiator. Heat of solar cell module is radiated in the earth by geothermal exchanger. An a result, geothermal exchanger is increased generation amount of solar cell module and experiment result showed costs to about 36% increment of generation power.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.889-892
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• 2008

This study, having combined and displaced fly ash known as admixture material that delays hydration reaction with coarse particle cement("CC" hereinafter) collected in particle classification method during ordinary portland cement("OPC" hereinafter), reviewed the hydration heat characteristics affecting the concrete. To reduce hydration heat, the study plain-mixed which used 100% OPC for WB 50% level 1, displaced CC at level 3 of 25%, 50% and 75% for OPC, and by displacing FA with admixture material at level 5 of 0%, 10%, 20%, 30% and 40%, experimented totally 16 batches. As a result of experiment, in the case of flow, the more CC displacement rate increased, the more it tended to decrease, and the more FA displacement rate increased, the more it decreased. As for simple adiabatic temperature rise by the CC and FA displacement rates, it decreased as displacement rate increased, and particularly in the case of FA40, temperature rise amount, $5.8{\sim}7.4^{\circ}C$, was very low. Compressive strength decreased in proportion to displacement rate, however strength reduction increment was shown to decrease with age progress.

• Safety and Health at Work
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• v.1 no.2
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• pp.175-182
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• 2010

Objectives: This study examined how ethanolamines (EAs) with the same functional alcohol group ($HOCH_2CH_2$), such as mono-EA (MEA), di-EA (DEA), and tri-EA (TEA), in water-based metalworking fluids (wbMWFs) are vaporized, condensed, and transformed by heat generated during metalworking. Methods: Two types of experimental apparatus were manufactured to achieve these objectives. Results: Vaporization tests using a water bath showed that the vaporization rate increased markedly from $0.19\;mg/m^2{\cdot}min$ at $23.5^{\circ}C$ to $8.04\;mg/m^2{\cdot}min$ at $60^{\circ}C$. Chamber tests with a heat bulb revealed that "spiked" MEA was fully recovered, while only 13.32% of DEA and no TEA were recovered. Interestingly, non-spiked types of EAs were detected, indicating that heat could convert EAs with more alcohol groups (TEA or DEA) into other EAs with fewer group(s) (DEA or MEA). The EA composition in fresh fluid was 4% DEA, 66% TEA, and 30% MEA, and in used fluids (n = 5) was 12.4% DEA, 68% TEA, and 23% MEA. Conversion from TEA into DEA may therefore contribute to the DEA increment. Airborne TEA was not detected in 13 samples taken from the central coolant system and near a conveyor belt where no machining work was performed. The DEA concentration was $0.45\;mg/m^3$ in the only two samples from those locations. In contrast, airborne MEA was found in all samples (n = 53) regardless of the operation type. Conclusion: MEAs easily evaporated even when MWFs were applied, cleaned, refilled, and when they were in fluid storage tanks without any metalworking being performed. The conversion of TEA to DEA and MEA was found in the machining operations.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.638-643
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• 1999

In this study we prepared 5 types of nutritional beverage base samples containing various ratios of soy protein isolate (SPI) and sodium caseinate as protein source. The rheological properties of each sample were measured and the results were as followes; Samples changed their rheological properties with the ratio of SPI. Samples represented newtonian property with low ratio of SPI, pseudoplastic property with the increment of SPI, and bingham pseudoplastic property with higher increment of SPI (80% as protein source). In this result we conjectured that the more was the SPI, the more was the formation of progel during heat treatment, which could be the reason of the rheological changes. In the test of the relationship between temperature and apparent viscosity, apparent viscosity of samples decreased along with the increment of temperature. In observing the relationship between time and apparent viscosity, we found sample, containing high ratio of SPI (80%), represented thixotropic property clearly with the hysteresis loop.

• Journal of Animal Science and Technology
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• v.58 no.1
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• pp.2.1-2.10
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• 2016

Background: Heat stress adversely affects the physiological and metabolic status, and the productive performance of buffalo. Methods: The present study was conducted to explicate the effect of misting and wallowing cooling strategies during heat stress in lactating Murrah buffalo. The study was conducted for three months (May-July) of which first two months were hot dry and last month was hot humid. Eighteen lactating buffaloes, offered the same basal diet, were blocked by days in milk, milk yield and parity, and then randomly allocated to three treatments: negative control (no cooling), cooling by misting, and cooling by wallowing. Results: The results showed higher (P < 0.05) milk yield in buffaloes of misting and wallowing group compared to control during the experimental period however wallowing was found more (P < 0.05) effective during July (hot humid period). Both the treatments resulted into significant (P < 0.05) reduction in rectal temperature (RT) and respiratory rate (RR) compared to control animals during study period whereas wallowing was found to be effective on pulse rate (PR) only during July. Both treatments were resulted in mitigating the heat stress mediated decrease in packed cell volume (PCV), lymphocytopnoea and neutrophilia whereas decrease in total erythrocyte count (TEC) and monocytes was only mitigated by wallowing. Heat load induced alteration in serum creatinine and sodium concentration was significantly (P < 0.05) ameliorated by misting and wallowing whereas aspartate aminotransferase, alkaline phosphatase and superoxide dismutase activity, and reactive oxygen species concentration could be normalized neither by misting nor by wallowing. The significant (P < 0.05) increment in serum cortisol and prolactin levels observed in June and July period in control animals was significantly (P < 0.05) prevented by misting and wallowing. Conclusions: It can be concluded that misting and wallowing were equally effective in May and June (hot dry period) whereas wallowing was more effective during hot humid period in preventing a decline in milk production and maintaining physiological, metabolic, endocrine and redox homeostasis.

• Journal of the Korean Solar Energy Society
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• v.38 no.2
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• pp.33-43
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• 2018

PV/Thermal module is the combined system, which consist of a photovoltaic module and solar thermal collector that can obtain electrical power and thermal energy simultaneously. Thus the power generation can be increase by decreasing the temperature of photovoltaic module and thermal energy retrieved from module also can be used for heating system. In this study, Heat transfer performance of air type PV/Thermal module was confirmed with various bottom obstacles that can be installed easily to real photovoltaic module by CFD (computational fluid dynamics) analysis. Eight type obstacles were investigated according to the shape and arrangement. As a result, nusselt number represent heat transfer performance was increased about 86% compare with the basic type PV/Tthermal module that has no obstacle and triangle type obstacle had higher value than other types. But pressure drop was also increased with increment of heat transfer enhancement. Thus the performance factor considering both heat transfer and pressure drop was confirmed and V-fin type obstacle arranged in a row for Reynolds number below 9,600 and protrusion type obstacle arranged in zigzag for Reynolds number above 14,400 were shown higher performance factor than other types. From these results, V-fin type obstacle arranged in row and protrusion type obstacle arranged in zigzag were considered as a proper type for applying to real PV/thermal module according to operating condition. But the heat transfer performance can be changed by the geometric conditions of obstacle such as height, width, length and arrangement. Thus, it could also confirmed that the optimal condition and arrangement of this obstacle need to be found in further study.

• Journal of Aquaculture
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• v.17 no.4
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• pp.268-274
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• 2004

Olive flounder was treated with oxytetracycline (OTC) and changes in blood physiology, antioxidant enzymes and heat shock protein (HSP) were recorded to obtain preliminary data for optimal OTC treatment. Blood parameters were measured 1 and 3 h after the OTC treatments at the concentration of 0 (control), 100, 300 and 500 ppm for I h. Hematocrit decreased with time, however the difference was not significant (P>0.05). Reduced number of red blood cell was observed with increasing OTC concentration. Serum glucose level increased as the OTC concentration increased. However, glucose level was similar to control after 3 h. Blood total protein decreased immediately after the OTC treatment but increased after 1 and 3 h. However, the increment in blood total protein was low. Activities of superoxide dismutase enzymes in 300 and 500 ppm groups increased by the OTC concentration. Catalase enzyme activity was negatively affected by the OTC concentration. However, the differences were not significant (P>0.05). High expression of HSP-70 protein was recorded for groups treated with 100 and 500 ppm compared to that of the control group. However HSP-70 mRNA showed a lower increment which was not significant (P>0.05).

• Journal of Practical Agriculture & Fisheries Research
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• v.4 no.1
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• pp.128-137
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• 2002

This study was conducted to develop the heat exchanger by utilizing the heat energy of underground water(15℃), which might be used for cooling and heating system of the agricultural facilities. We developed the heat exchanger by using the parallel type plat fin tube made of Aluminum(Al 6063), which was named Aloo-Heat(No. 0247164, offered by Korean Intellectual property Office). The trial manufactures were made from Aloo-heat which was 600mm, 700mm length respectively, and It were welded to the end "U" type in order to direct flow of the underground water. The performance test was carried out under the condition of open space and room temperature with the change of flow rate of the underground water and air. The results are as follows. 1. The trial manufactures had convection heat value from 33 to 156 W/m²℃, and It was coincided with design assumption. 2. The amount of energy transfer was increased with the increment of the area of heat transfer, the air flow, the gap of temperature inlet & outlet the underground water and the air. 3. The heat value was 6,825W when the air flow was 6,000m³/h and the gap of temperature between inlet and outlet of the underground water was 6℃, and It dropped from 25.8℃ to 23.2℃(-2.6℃ difference). The convection heat value was 88.5W/m²℃. 4. The heat value was 2.625W when the air flow was 4,000m³/h and the gap of temperature between inlet and outlet the underground water was 2℃, and It dropped from 27℃ to 22.5℃(-4.5℃ difference). The convection heat value was 33.6W/m²℃. 5. Correlation values(R²) of the testing heat values of the trial manufacture type I, II, and III were 0.9141, 0.8935, and 0.9323 respectively, and correlation values(R²) of the amount of the air flow 6,000m³/h, 5,000m³/h, 4,000m³/h were 0.9513, 0.9414, and 0.9003 respectively.