• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.3
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• pp.199-212
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• 2007

If a type IP-2 transport package were to be subjected to a free drop test and a penetration test under the normal conditions of transport, it should prevent a loss or dispersal of the radioactive contents and a more than 20% increase in the maximum radiation level at any external surface of the package. In this paper, we suggested the analytic method to evaluate the structural safety of a type IP-2 transport package using a thick steel plate for a structure part and a bolt for tying a bolt. Using an analysis a loss or dispersal of the radioactive contents and a loss of shielding integrity were confirmed for two kinds of type IP-2 transport packages to transport radioactive waste drums from a waste facility to a temporary storage site in a nuclear power plant. Under the free drop condition the maximum average stress at the bolts and the maximum opening displacement of a lid were compared with the tensile stress of a bolt and the steps in a lid, which were made to avoid a streaming radiation in the shielding path, to evaluate a loss or dispersal of radioactive waste contents. Also a loss of shielding integrity was evaluated using the maximum decrease in a shielding thickness. To verify the impact dynamic analysis for free drop test condition and evaluate experimentally the safety of two kinds of type IP-2 transport packages, free drop tests were conducted with various drop directions. For the tests we examined the failure of bolts and the deformation of flange to evaluate a loss or dispersal of radioactive material and measured the shielding thickness using a ultrasonic thickness gauge to assess a loss of shielding integrity. The strains and accelerations acquired from tests were compared with those by analyses to verify the impact dynamic analysis. The analytic results were larger than the those of test so that the analysis showed the conservative results. Finally, we evaluated the safety of the type IP-2 transport package under the stacking test condition using a finite element analysis. Under the stacking test condition, the maximum Tresca stress of the shielding material was 1/3 of the yielding stress. Two kinds of a type IP-2 transport package were safe for the free drop test condition and the stacking test condition.

• Journal of the Korean Wood Science and Technology
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• v.44 no.1
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• pp.30-39
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• 2016

The evaluation of the lateral load performance for larch glulam portal frames was carried out using glass fiber reinforced plastic (GFRP) as connector in two different systems: the GFRP-reinforced laminated plates combined with veneer, and GFRP rod joints glued with epoxy resins to replace usual metal connectors for the structural glulam rahmen joints. As a result the yield strength, ultimate strength, initial stiffness of glulams of GFRP rod joints glued with epoxy resin decreased to 49%, 52% and 61% compared to those of the conventional metal connector. This connector will be a stress device where the bonding strength between the GFRP rod and glued laminated timber is important. Thus, there will be a high possibility that a problem may occur when it is applied to the field. On the other hand, the GFRP-reinforced laminated plates and wood (Eucalyptus marginata) pin were measured all within 3% for all measurements of the yield strength, ultimate strength, initial strength and ductility factor, regardless of high cross sectional loss on the glued laminated timber slit joint. In addition, the variation of stiffness on the cycle was 35%, which was the lowest, confirming that it was almost the same performance as the specimen prepared with the metal connector.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.267-271
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• 2015

This study aimed to determine the optimal freezing temperature for preserving mulberries. Mulberries were frozen at -20, -45, and $-70^{\circ}C$ immediately after harvesting. After 24 h, frozen mulberries were stored at $-20^{\circ}C$ for two months and then thawed at $4^{\circ}C$ and room temperature. Frozen and thawed mulberries did not differ significantly in color and pH from fresh mulberries. However, the content of anthocyanidin and sugar, and the hardness of mulberry significantly decreased after feeze-thawing. Drip loss of the thawed berries increased as the freezing temperature decreased. A comparison among cross-section images of mulberries frozen at different temperatures did not show any significant differences. However, after thawing at $4^{\circ}C$ or room temperature, the total number of aerobic bacteria found in mulberry decreased more than ten times. Consequently, the freezing temperature showed no significant effect on the overall quality of the mulberry.

• Journal of Animal Science and Technology
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• v.50 no.5
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• pp.657-666
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• 2008

This study investigated the effects of dietary probiotics which contained antioxidant astaxanthin on growth performances and meat quality in two pigs farms. A total of 2,400 pigs were gilt and barrow with same number assigned to one of two treatments. The two treatments were control(commercial feed), treatment(probiotics 0.1% feed). Each treatment had 3 replicates. Weight gain, feed intake and feed efficiency were periodically recorded for 90 days. Survival ratio was shown 99.85% in treatment group. Average daily gain was higher in treatment group(0.91kg) than that of control(0.84kg). Back fat thickness was lower in treatment group than that of control, even though the treatment group tended to be higher carcass weight. The treatment group trended higher carcass weight, back fat thickness was lower in treatment group than control. The ratio of carcass grade A was shown higher in treatment than that of control, respectively. Treatment group showed higher value of fat content and water holding capacity. Treatment showed lower value than control in shear force and cooking loss. Hunter value(a and b) of treatment group in meat color was higher than control. Treatment group was lower cholesterol content than control. Control group was shown higher unsaturated fatty acid(stearic acid(C18:0)) value than treatment. Treatment group was shown lower saturated fatty acid(oleic acid(C18:1)) value than that of control. These results suggested that the supplementation of probiotics contained Phaffia rhodozyma could be used effectively for increase productivity of livestock industry.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.1
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• pp.21-26
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• 1994

Lysimeter experiments were carried out to study the vertical distribution of inorganic nitrogen, the changes in pHs of soil and leachate and the fate of applied nitrogen with or without grass. The concentration of $NO_3-N$ of surface soil(0~20cm) at the rates of 0, 7, 14 and 21kg N/10a ranged from 4 to 13mg/kg, while those of subsurface soi1(20-40cm) were below 10mg/kg at 0, 7 and 14kg N/10a and subsequently increased to 83.8mg/kg at 35kg N/10a. The concentration of $NH_4{^+}-N$ was positively correlated with that of $NO_3-N$ for surface soil(>0.05). However, the concentration of $NH_4{^+}-N$ was negatively correlated with that of $NO_3-N$ for subsurface soil. A positive correlation was observed between $NO_3-N$ and extractable cations of soils. The pH of subsurface soil decreased with the $NO_3-N$ concentration and the N application rate, while that of leachate inereased with the N application rate. The pH differences between subsurface soil and leachate were 2.5 for bare soil and 3.1 for 35kg N/10a. Higher N application rate caused more soil N accumulation and the gas loss and resulted in a larger difference between N uptake by grass and the applied N.