• Journal of Aquaculture
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• v.21 no.4
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• pp.226-233
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• 2008

This study investigated the effects of dietary moisture level and storage temperature on lipid oxidation and fatty acids composition of the extruded pellet feed. The diets containing the moisture levels of 5%, 15% and 25% were prepared by adding moisture (water) to the commercial extruded pellets and stored at $5^{\circ}C$, $20^{\circ}C$ (room temperature) and $35^{\circ}C$. The samples for analysis were collected at every 2 days for 10 days. Acid value (AV), peroxide value (POV), 2-thiobarbituric acid (TBA) value and fatty acid composition of the feeds were measured. No differences in the AV, POV and TBA value were observed in feed containing 5% moisture at all storage temperatures for 10 days. However, the AV, POV and TBA value of diets containing 15% and 25% moisture increased rapidly at $20^{\circ}C$ and $35^{\circ}C$ after 4 days. Fatty acids compositions of feeds containing 5% moisture did not change during the storage periods at $5^{\circ}C$ and $20^{\circ}C$. However, 5% moisture feed stored at $35^{\circ}C$ increased monoene fatty acid content and decreased the contents of polyene fatty acid, PUFA (polyunsaturated fatty acid)/SFA (saturated fatty acid) and $(C_{20:5}+C_{22:6})/C_{16:0}$ after 4 days. Also, 15% moisture feed stored at $35^{\circ}C$ showed increased monoene fatty acid content and decreased $(C_{20:5}+C_{22:6})/C_{16:0}$ after 2 days. The diet containing 25% moisture showed increased monoene fatty acid content and decreased contents of PUFA, PUFA/SFA and $(C_{20:5}+C_{22:6})/C_{16:0}$ at all temperatures after 2 days. In this study, lipid oxidation can occur in the extruded pellet feeds of 15% and 25% moisture at room temperature after 2 days.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.5950-5957
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• 2012

CPR with minimized hands-off time is one of integral factors for the improvement of the survival rate of patients. The purpose of this study was to examine the relationship of the installation of C-steps on the main stretcher to CPR accuracy and errors. The subjects in this study were 70 paramedics in 10 firehouses in the province of C(35 for control group, 35 for experimental group), and their CPR accuracy on the main stretchers was checked. As a result, it's found that the main stretchers equipped with the C-steps served to boost the accuracy of chest compression by creating suitable environments for that in terms of height and posture(t=65.104, p=.000), to improve the accuracy of artificial respiration by providing a proper amount of ventilation(t=5.207, p=.000), and to bolster the self-confidence of the paramedics about CPR(t=-10.612, p=.000). In conclusion, the mounting of C-steps on the main stretcher is expected to be of use for the improvement of the survival rate of cardiac-arrest patients by ensuring the precise performance of high-quality CPR.

• Journal of the Korean Society of Tobacco Science
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• v.2 no.1
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• pp.61-67
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• 1980

The greenhouse hulk curing and drying system utilizing the direct solar energy was tested to see how much fuel could be saved for curing flue-cured tobacco at the Daegu Experiment Station, Korea Tobacco Research Institute (North latitute: 35$^{\circ}$49'), in 1979. The structure consists of transparent fiberglass exterior, polyurethan boards covered with galvanized iron as the heat absorbers and insulation boards, air duct in which the air is introduced to the furnace room of bulk curing barn, and gravel heat storage system. All exterior surface of heat absorbers, air duct, and gravels were coated with black paint. The air temperature and total radiation were 20.5 to 35.5$^{\circ}C$ and 1004.2 to 1436.2 cal/$\textrm{cm}^2$ during the 3 replicated curing tests, respectively. The greenhouse bulk curing and drying system was able to cut fuel consumption by 25 percent compared with the conventional bulk curing barn. The maximum temperatures for the top absorber and the inlet air of the system were 89$^{\circ}C$ and 64$^{\circ}C$, respectively, and the average temperature of inlet air was higher than that of conventional one by 18$^{\circ}C$.

• Journal of the Korean Society for Heat Treatment
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• v.7 no.1
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• pp.44-52
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• 1994

In order to investigate the effect of tempring treatment on the mechanical properties of ausformed martensite in Fe-30%Ni-0.35%C alloy, the hardness, yield strength and elongation were examined by tensile test. 1. The strength of deformed austenite in Fe-30%Ni-0.35%C alloy was increased due to the work hardening induced from the dislocation density increased during deformation. The strength of ausformed martensite was increased because of defects inherited from deformed austenite by martensitic transformation. 2. The ductility of ausformed martensite was shown a nearly constant values independent of deformation degrees because of the interaction of multiple factors such as increased retained austenite, formation of void and decrement of twin in ausformed martensite. 3. The strength of ausformed martensite by tempering treatment was shown a little decrement up to $340^{\circ}C$, especially showed remarkable softening resistance in higher deformation degrees. 4. Virgin martensite and ausformed martensite were shown a maximum yield strength by clustering in tempering at $100^{\circ}C$ and above $100^{\circ}C$, yield strength was very small decreased due to the decrement of solute carbon by the destruction of clustering. 5. The decomposition of retained austenite was not shown up to $450^{\circ}C$ in ausformed martensite with tempering treatment, and the matrix was rapidly softening because of the decomposition of martensite and the formation of reversed austenite with tempering above $400^{\circ}C$.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.756-762
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• 2011

This study was conducted to investigate the effects of moisture content on microbiological stability and texture characteristic of dry-cured ham. The moisture content of dry-cured hams was adjusted to 35% (C) or 45% (T) and then vacuumpackaged after slicing to a 1 inch thickness. All packaged dry-cured hams were stored at $10^{\circ}C$ for 3 mon, and physicochemical analyses and a sensory evaluation were conducted to verify the quality of dry-cured hams during four different storage periods. Moisture content was significantly higher in T (44.89%) compared to that in C (35.03%). However, crude fat content was higher in C (14.08%) than that in T (11.11%). The pH, salinity, and shear force were higher in C than those in T, and dry-cured hams derived from C seemed to provide low lipid oxidation stability during storage. In contrast, T showed high CIE $L^*$, CIE $a^*$ and CIE $b^*$, and aw values when compared to dry-cured hams from C. Total plate counts and Lactobacillus tended to increase with the increase in storage period, and both were lower in T than those in C after 1 mon of storage. Our results indicate that 45% moisture content improved dry-cured ham quality as compared to that of dry-cured hams containing 35% moisture.

• Journal of Biosystems Engineering
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• v.24 no.2
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• pp.107-114
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• 1999

To find the best combustion conditions in the heavy oil burner kinetic viscosity of heavy oil A, B and C at different temperature range, from 40 to 140$^{\circ}C$, and the droplet sizes of the heavy oils at different temperature and pump pressure were measured. And, combustion characteristics were investigated under the different conditions : two different heavy oil and three different oil temperature. At temperature of 70, 100, 130$^{\circ}C$ the kinetic viscosity of heavy oil A and B are 7.9, 5.7, 4.3 and 30.4, 13.7, 7.9cSt, respectively. The greatest and smallest viscosity were 7,455 cSt at C oil on 27$^{\circ}C$ and 4.26cSt at A oil on 140$^{\circ}C$. The magnitude of viscosity difference between at 100$^{\circ}C$ and 140$^{\circ}C$ under 6 cSt in cases of A and B oil, but more than 30cST on C oil. Of the droplet sizes, the biggest and smallest droplet size in A oil were 98$\mu\textrm{m}$ at oil temperature of 130$^{\circ}C$(4.3cSt), pump pressure of 1.57MPa and 72$\mu\textrm{m}$ at 70$^{\circ}C$(7.9cSt), 2.35MPa, respectively. It appeared that as spraying pressure increased the droplet size decreased, however, no distinct differences were found in the effects of kinetic viscosity on the droplet sizes of the test range. The best combustion performance was observed when droplet size, spraying pressure and oil temperature were 73$\mu\textrm{m}$, 2.35MPa and 70$^{\circ}C$ producing CO2 of 13.1%, CO of 13ppm and flue gas temperature of 250$^{\circ}C$ in A oil combustion For B oil, it was100$^{\circ}C$, 2.35MPa, 52$\mu\textrm{m}$, producing CO2 of 10ppm and flue gas temperature of 260$^{\circ}C$. In general, it appeared that better combustion results were observed in the smaller droplets produced burner condition.

• Journal of the Korean Ceramic Society
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• v.23 no.1
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• pp.67-73
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• 1986

SiC and $SiC-Si_3N_4$ powder were synthesized via the carbiding and carbiding-nitriding reaction of Jecheon quartz respectively using graphite as a reducing agent. $\beta$-SiC+($\alpha$+$\beta$)-$Si_3N_4$ composite was obtained by the carbiding-nitriding reaction of Jecheon quartz-graphite mixture at 1, 35$0^{\circ}C$ in $H_2$ atmosphere. $\beta$-SiC+($\alpha$+$\beta$)-$Si_3N_4$ composite was obtained by the carbidint-nitriding reaction of Jecheon quartz-graphite mixture at 1, 35$0^{\circ}C$ in $N_2-H_2$ atmosphere. The ratio of $\beta$-SiC+($\alpha$+$\beta$)-$Si_3N_4$ content in a produced composite could be controlled by adjusting the reaction time and gaseous mixture.

• Journal of the Korean Society of Safety
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• v.16 no.1
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• pp.31-36
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• 2001

Surface crack growth characteristics and influence of the stress amplitude in rotary bending fatigue test were evaluated for annealed S35C steel, and than fractal dimensions of fatigue crack paths estimated using the box counting method. The following results that will be helpful to understand the fatigue crack growth mechanism were obtained. (1) Crack growth rate ds/dN and db/dN (s : half crack length at the surface crack, b : crack depth) depended on stress amplitude (${\Delta}{\sigma}/2$), stress intensity factor range (${\Delta}K_A, {\Delta}K_C$) and crack length. (2) At the effect area of 0.3 mm hole notch (s＜0.5 mm) crack growth rate did not depend on these factors. (3) The fractal dimensions (D) increased with stress amplitude (${\Delta}{\sigma}/2$) but decreased with cyclic number.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2611-2612
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• 2014

• Proceedings of the Korean Vacuum Society Conference
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• 1997.07a
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• pp.35-35
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• 1997