• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.3
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• pp.403-414
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• 1994

Nonlinear analysis of RC containment structure under thermal load and pressure is presented to trace the behaviour after an assumed LOCA. The temperature distribution varying with time through the wall thickness is determined by transient finite element analysis with the two time level scheme in time domain. The layered shell finite elements are used to represent the containment structures in nuclear power plants. Both geometric and material nonlinearities are taken into account in the finite element formulation. The constitutive relation of concrete is modeled according to Drucker-Prager yield criteria in compression. Tension stiffening model is used to represent the tensile behaviour of concrete including bond effect. The reinforcing bars are modeled by smeared layer at the location of reinforcements accounting elasto-plastic axial behaviors. The steel liner model under Von Mises yield criteria is adopted to represent elastic-perfect plastic behaviour. Geometric nonlinearity is formulated to consider the large displacement effect. Thermal stress components are determined by the initial strain concept during each time step. The temperature differential between any two consecutive time steps is considered as a load incremental. The numerical results from this study reveal that nonlinear temperature gradient based on transient thermal analysis will produces excessive large displacement. Nonlinear behavior of containment structures up to ultimate stage can be traced reallistically. The present study allows more realistic analysis of concrete containment structures in nuclear power plants.

• 한국해양학회지
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• v.22 no.1
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• pp.1-8
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• 1987

The Sinyangri Formation crops out in the vicinity of the Seongsan Peninsula, Cheju Island. Based on sedimentary structures, texture and composition, the lithologic sequence has been classified, in ascending stratigraphic order, into three lithofacies: parallel laminated sandstone facies (Facies I): conglomerate facies(Facies Il); and cross stratified sandstone facies (F acies Ill). Wedge-to-parallel, seaward-inclined in low angle less than 10$^{\circ}$lamina -sets with alternations of coarseand fine-grained sediments in the Facies I are the characteristic sedimentary structures in the foreshore depositional environment. Grains of this faciesare well sorted with good roundness compared with the other two facies, partly showing inverse graded bedding. Facies II,largely composed of claset-supported,very poorly-sorted conglomerates,does not pinch out but occurs continuously along the Sinyangri beach.Interstitial spaces between the clasts are mostly infilled with volcanic-ash and small amounts of well-rounded shell fragments.Maximum bed thickness as well as the size of imbedded basaltic clasts decreases to the south(toward Sinyangri). Large clasts with parallel lamination originated from the underlying Facies i,are generally elongated parallel to the bedding plane and display no systematic horizontal variations in size indicative of in-situ clasts.In view of the facts above it seems that large gravels from the basaltic rocks are transgressive lag conglomerates which are partly affected by the combination of longshore currents and propagating wave.Local occurrence of cross-strata dipping toward the south in the upper part of Facies IIreinforces the evidence of the action of longshore currents. Facies IIIis characterized by bidirectional trough cross-starifiction and wave ripples associated with the upper shoreface(surfzone) environments.In summary,the Sinyangri Formation represents the depositional environments of foreshore to upper shoreface truncated by disconformity between Facies Iand II.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.1
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• pp.41-50
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• 2006

In this paper, sets of engineering analyses were conducted to renew the overall dimensions and configurations of a disposal container proposed as a prototype in the previous study. Such efforts and calculation results can provide new design variables such as the inner basket array type and thickness of the outer shell and the lid & bottom of a spent nuclear fuel disposal container. These efforts include radiation shielding and nuclear criticality analyses to check to see whether the dimensions of the container proposed from the mechanical structural analyses can provide a nuclear safety or not. According to the results of the structural analysis of a PWR disposal container by varying the diameter of the container insert, the Maximum Von Mises stress from the 102 cm-container meets the safety factor of 2.0 for both extreme and normal load conditions. This container also satisfies the nuclear criticality and radiation safety limits. This decrease in the diameter results in a weight loss of a container by $\sim20$ tons.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.7
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• pp.1006-1013
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• 2015

Heat-stress remains a costly issue for animal production, especially for poultry as they lack sweat glands, and alleviating heat-stress is necessary for ensuring animal production in hot environment. A high ${\gamma}$-aminobutyric acid (GABA)-producer Lactobacillus strain was used to investigate the effect of dietary GABA-producer on laying performance and egg quality in heat-stressed Hy-line brown hens. Hy-Line brown hens (n = 1,164) at 280 days of age were randomly divided into 4 groups based on the amount of freeze-dried GABA-producer added to the basal diet as follows: i) 0 mg/kg, ii) 25 mg/kg, iii) 50 mg/kg, and iv) 100 mg/kg. All hens were subjected to heat-stress treatment through maintaining the temperature and the relative humidity at $28.83{\pm}3.85^{\circ}C$ and 37% to 53.9%, respectively. During the experiment, laying rate, egg weight and feed intake of hens were recorded daily. At the 30th and 60th day after the start of the experiment, biochemical parameters, enzyme activity and immune activity in serum were measured. Egg production, average egg weight, average daily feed intake, feed conversion ratio and percentage of speckled egg, soft shell egg and misshaped egg were significantly improved (p<0.05) by the increasing supplementation of the dietary GABA-producer. Shape index, eggshell thickness, strength and weight were increased linearly with increasing GABA-producer supplementation. The level of calcium, phosphorus, glucose, total protein and albumin in serum of the hens fed GABA-producing strain supplemented diet was significantly higher (p<0.05) than that of the hens fed the basal diet, whereas cholesterol level was decreased. Compared with the basal diet, GABA-producer strain supplementation increased serum level of glutathione peroxidase (p = 0.009) and superoxide dismutase. In conclusion, GABA-producer played an important role in alleviating heat-stress, the isolated GABA-producer strain might be a potential natural and safe probiotic to use to improve laying performance and egg quality in heat-stressed hens.

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.577-586
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• 2017

The aim of this study was to investigate the effects of fermented earthworm cast feed prepared with three complexed probiotics containing Bacillus subtilis separated from the earthworm casts, on egg production, egg quality and odor removal from poultry house. A total of 240 laying hens were divided into 4 treatments and completely randomized. Experimental groups were divided into control, 0.3 to 0.5% (fermented earthworm cast feed FECF3, FECF5) and 0.2% commercial probiotics (CP). The egg production rate was significantly higher in the FECF groups compared to the control group fed the normal feed, but there was no difference in the CP group. Haugh units, egg shell thickness, breaking strength, egg yolk index and albumen height were increased in FECF groups compared to control but not in CP group. The n-3 content of eggs was higher in the FECF groups than in the control group, while the n-6/n-3 ratio was lower and there was no difference from the CP group. Ammonia production was lower in the CP and FECF groups compared to the control group after 5 days storage at room temperature to poultry feces.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1299-1304
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• 2005

An experiment was conducted to study the production performance of broiler breeder females (25 to 40 weeks of age) fed either reference diet or low non-phytate phosphorus (NPP) diet with or without microbial phytase (500 FYT/kg) supplementation. A weighed (160 g/b/d) quantity of feed from each diet was offered daily to 40 replicates of one bird each housed in California type cage having individual feeders. Each cage was considered as a replicate. A continuous 16-h light per day was provided using incandescent bulbs. Body weight, egg production, egg weight, feed per egg mass, egg specific gravity, egg breaking strength, shell thickness, tibia ash and serum Ca and protein concentrations were not affected by reducing the NPP level from 0.30 to 0.18% in the broiler breeder diet. Supplementation of phytase (500 FYT/kg) enzyme to the diet containing 0.18% NPP had no added advantage on any of the above production parameters. The serum inorganic P was increased significantly (p<0.05) by either enhancing the NPP content from 0.18 to 0.30% or supplementing phytase @500 FYT/kg to the diet containing low P which were found comparable. Retention of Ca and P was positive on all the diets. P retention decreased significantly (p<0.05) with either increase in NPP content or phytase supplementation in the diet. Neither NPP nor phytase supplementation influenced bone mineralization in terms of tibia ash and strength. The hatchability was not influenced by either increasing the NPP content or supplementing the enzyme phytase. Similarly, the P concentration in the egg yolk and day old chick, day old and 14th day body weight and leg score was not altered by increasing the level of NPP or supplementing phytase enzyme. The mortality was within the normal limits in all the three dietary groups. Thus, it can be concluded that 0.18% NPP (288 mg NPP intake/b/d) in the broiler breeder' diet is adequate in sustaining the optimum performance from 25 to 40 wks of age. Enhancing the NPP content or supplementation of phytase (500 FYT/kg diet) to diet containing 0.18% NPP had no added advantage on performance.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.11a
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• pp.153-162
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• 2005

In this Paper, sets of engineering analyses were conducted to renew the overall dimensions and configurations of a disposal container proposed as a prototype in the previous study. Such efforts and calculation results can provide new design variables such as the inner basket array type and thickness of the outer shell and the lid & bottom of a spent nuclear fuel disposal container. These efforts include radiation shielding and nuclear criticality analyses to check to see whether the dimensions of the container proposed from the mechanical structural analyses can provide a nuclear safety or not. According to the results of the structural analysis of a PWR disposal container by varying the diameter of the container insert, the Maximum Von Mises stress from the 102 cm container meets the safety factor of 2.0 for both extreme and normal load conditions. This container also satisfies the nuclear criticality and radiation safety limits. This decrease in the diameter results in a weight loss of a container by ${\~}$20 tons.

• Journal of Aquaculture
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• v.18 no.3
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• pp.142-146
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• 2005

In this study, the reattachment processes of small and medium size of spot of Mytilus coruscus and M. edulis were observed. The small spats (Shell length, SH, $3{\sim}7mm$) of hard shelled mussel, M. coruscus showed 100% reattachment rate within 7 minutes after the detachment of byssus thread and 100% survival rate. While large spats (SH 25 mm) showed 85% reattachment rate within 5 hours and 100% survival rate for 24 hours. The reattachment rate of M. edulis (SH 30 mm) was higher than that of M. coruscus (SH, 28 mm). The thread consisted of three identifiable structures; adhesive disc, adhesive thread and adhesive root. The adhesive disk and adhesive thread of M. coruscus were larger and thicker than those of M. edulis, whereas the thickness of adhesive root was the other way round. Further studies are required to identify the relationship between the structure of byssus thread and attachment ability. This study suggests that the sizes of spats could be an important factor in determining the timing of removing and reattaching mussel seedling for aquaculture or releasing to the sea.

• Korean Journal of Poultry Science
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• v.33 no.1
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• pp.41-47
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• 2006

A study was conducted to investigate the effect of supplementing earthworm meal(EWM) on the egg quality and performance of laying hens. A total of 360 laying hens at 55 weeks of age were fed the experimental diets containing 0(Control), 0.3 and 0.6% of EWM for 5 weeks. Eggs were collected and weighed in every day and egg production and feed conversion were weekly recorded. However egg quality were measured fer last week of experimental period. When fed both 0.3 and 0.6% of EWM, egg production and daily egg mass tended to increase but were not different between those treatments. Feed intake and feed conversion ratio of laying hens were not different among three groups. Egg shell thickness, breaking strength, color and egg yolk color were tend to improve in both 0.3 and 0.6% of EWM compared to those of control. The haugh units(HUs) showed no difference among each treatments at 14 after laying egg, but increased in EWM treatments compared to control for storage period. As, Cd, Cr, Hg and Pb detected 4.41, 1.23, 1.18, 0.00 and 3.39ppm in EWM, respectively, but which were not detected in control. It assumed that supplementing 0.3% of earthworm meal in the 55 weeks old laying hens diet, improved the laying performance and egg quality.

• Journal of Animal Environmental Science
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• v.14 no.1
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• pp.47-52
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• 2008

Broken eggs not only cause the economic loss in the egg producing industry, but also may not be good for the consumer's health. In order to identify the causes of eggshell breakage in laying hen houses, analyses on the status of eggshell breakage in the step of egg conveyer system of the laying hen house were conducted. The survey of eggshell breakage rate was implemented by four different stages egg conveying system. In the results, the breakage rate showed 4.7% in the egg collection belt, 2.5% in the egg elevator, 1.7% in the egg grading system and 0.9% in the egg conveyor belt. In particular, to Hy-line Brown variety, as the hens' raising week old increased, the breakage rate of eggshell increased while the strength of eggshell decreased. In the regression analysis between the breakage rate of eggshell and the strength of eggshell, the coefficient of determination ($R^2$) by the test of significance was computed as 0.7, therefore the changes of the strength of eggshell affects the breakage rate of eggshell. However, between the strength of eggshell and thickness of egg shell, and between the strength of eggshell and strain of eggshell, there was no significant difference detected in the regression analysis.