• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.2
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• pp.11-20
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• 1993

Nonlinear inelastic behavior of an HP saddle shell has been examined by a finite element computer program developed on a Cray Y-MP. The mesh convergence is studied using three progressively refined finite element mesh models, $16{\times}16$, $32{\times}32$ and $64{\times}64$, for the elastic and inelastic analyses. It is shown that the $32{\times}32$ mesh model gives a solution that is very close to that given by the $64{\times}64$ mesh model, thus, showing a convergence. The inelastic analysis shows that the shell has a tremendous capacity to redistribute the stresses. At the ultimate, the concrete cracks and the reinforcement yieldings are spread out all over the shell, indicating that the stress distribution in the shell is approaching that given by the classical membrane theory. The present computer program provides a very useful tool for evaluating the nonlinear ultimate behavior of concrete shells during the design process.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.486-491
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• 2005

Nowadays heat exchangers that have been applied for freon refrigerating systems, a shell and tube type condenser, but because of their large size, large space for installation and more amount of refrigerants are needed. Therefore, in this study, we will find the most suitable operating condition through the comparison of performance between the shell & tube type and shell & disk type heat exchanger with R22. The experiments are carried out for the condensing pressure of refrigeration system from 1500kPa to 1600kPa and for the degree of superheat from 0 to $1^{\circ}C$ at each condensing pressure. As a result of experiment, if the shell & disk type heat exchanger is applied for R22 refrigerating systems, minimized input of refrigerants and space required for installation will be secured, which will have a great contribute to financial improvement for industry.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.4
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• pp.493-500
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• 2013

In this study, it was evaluated the protective performance of the protection material for filed of the army by impact of fragment from the explosion of 155mm artillery shell to propose the improvement items. And it was evaluated the protection materials for structural boby such as corrugated steel plate, concrete block, prevention paint of explosion, aluminum foam and concrete T-wall by impact of fragment of 155mm artillery shells and explosion-induced pressure of C-4 explosive. As a result, protective performance of the existing protective material was superior but reinforcement is necessary for secondary damage because sand is leaking. The protective performance of new protective materials was greater than existing protective materials. And it can be used for protective materials.

• Korean Journal of Poultry Science
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• v.23 no.1
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• pp.39-46
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• 1996

An experiment was conducted to investigate the effect of feeding split diets for a.m. and p.m. in laying hens on egg shell qualities, and to study the relationship among the methods of measuring shell quality with 480 ISA Brown layers during 32∼36, 52∼56 and 72∼76 wk of age, respectively. A total of 1,080 eggs were collected from 6 treatment groups in every laying period and weighed individually. Egg specific gravity, egg breaking strength, shell thickness and shell percentage of eggs were measured, and then correlation coefficients (r) and regression equations were calculated. By feeding the split diets for a.m. and p.m. differing in ME, CP, and Ca levels, and as the Ca level of the p. m. diet increased, eggshell qualities were improved(P<0.05). The correlation coefficient values indicate that shell percentage, shell thickness and egg specific gravity are highly correlated with the egg breaking strength(P<0.01).

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.107-112
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• 2004

The combining abilities in the 5 newly evolved thermo tolerant breeds viz., SR6, SR7, SR8 SR9 and SR10 of silkworm Bombyx mori L. and their 15 hybrids were made in a line${\times}$tester crossing programme. Data were analysed for seven quantitative traits i.e., pupation rate, cocoon yield, cocoon weight, cocoon shell weight, cocoon shell ratio, filament length and raw silk percentage under optimum room temperature $(25{\pm}{1^{\circ}C})$ conditions (In case of high temperature $(36{\pm}{1^{\circ}C})$ stress conditions five economic traits except filament length and raw silk percentage) with 3 widely adapted testers i.e., KA, CSR2 and CC1 as lines (females) and testers (males) respectively. The performance at high temperature and low humidity conditions aye only taken into consideration for selecting the best lines/hybrids. Among the lines SR6 exhibited positive General combining ability (GCA) effects for pupation rate, cocoon yield, cocoon weight and cocoon shell ratio traits, followed by SR7 for pupation rate, cocoon yield and cocoon shell weight and cocoon shell ratio. Among testers, KA exhibited positive GCA effects for two quantitative traits cocoon yield, cocoon weight and CSR2 for cocoon shell weight and cocoon shell ratio under adverse temperature conditions. The hybrid SR6${\times}$CC1 and SR7${\times}$CSR2 exhibited significant positive Specific combining ability (SCA) effects for majority of the traits in high temperature stress conditions of rearing. The better parent value of heterosis(Heterobeltiosis) was exhibited by the hybrid SR6${\times}$CC1 for pupation rate, cocoon yield, cocoon weight and cocoon shell weight and SR7${\times}$CSR2 for all the trails evaluated under high temperature conditions. Based on the results, the lines SR6 and SR7 was judged as best combiners and the hybrids SR6${\times}$CC1 and SR7${\times}$CSR2 can be selected for commercial exploitation in tropical climate.

• Journal of Aquaculture
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• v.15 no.2
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• pp.95-101
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• 2002

During the periods from lily to October, 2000 in Hongseong and lucy to October, 2001 in Taean in the west coast of Korea, the following environmental conditions prevailed : water temperature : 22.0~26.817, salinity 27.23 ~30.80%, dissolved oxygen 4.12 ~6.26 ml/l, pH 7.89 ~8.09, phosphate 0.39 ~0.65 $\mu m$ , inorganic nitrogen 5.05~9.26 $\mu m$, suspended solid 5.4~20.8 mg/l and chemical oxygen demand 1.12~1.87 mg/l. The B-shaped veliger larvae of the Ark shell occurred in maximum number at $25^{\circ}C$ prevailing from mid-August at Hongseong and Taean. Full grown larvae reached maximum abundance from late August. To identify the effectiveness of the substratum for spat collection, raschel net were tested to Larval settlement. The most effective depth to collect the larvae in natural environment was the collectors suspended at 7~8 m depth. At these depths, about 49 to 94 spats were found on the collector (40$\times$50 cm), The growth of shell height (Y) to shell length (X), and total weight (W) to shell length (L) could be formulated as follows respectively: Hongseong: SH = 0.7168 SL -0.6466 ( $r^2$ = 0.9839), TW = $0.0001SL^{3.1705}$ ($r^2$ = 0.9882) Taean: SH = 0.736 SL -0.8824 ($r^2$ : 0.9899), TW : 0.00005 $SL^{3.3731}$ ($r^2$ : 0.9899)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.6
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• pp.353-358
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• 2005

The present study investigated the feces production rate and fecal nitrogen production ratio of abalone, Haliotis discus hannai fed seaweed, Undaria pinnatifida. The abalone, with shell lengths of 3 cm, 5 cm, and 7 cm, were tested at temperatures of $12^{\circ}C$, $16^{\circ}C$, and $20^{\circ}C$ in a semi-recirculating aquaculture system. Under the given experimental conditions, the weight specific feces production rate (FPw) of the abalone increased with the decrease of shell length and the increase of temperature. The relationship of the FPw was. $FPw=-3.092+206.573/T - 1916.8/T^2+0.141L -0.037L^2(r^2=0.9412)$. In addition the abalone produced 17.8-22.5% of fecal material against ingested seaweed, Undaria pinnatifida, and $18.4-22.4\%$ of nitrogen ingested total nitrogen.

• Design & Manufacturing
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• v.2 no.4
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• pp.16-23
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• 2008

This paper describes $R_p,\;R_d,\;R_c,\;R_{cp},\;R_{cd}$ for design and manufacture of die by comparing the results. Results of this study could be reduced from three processes to two processes and drawing can be conducted using one die set by modifying structure of the punch head and die plate. Oil canning phenomenon can be prevented when circle blanking or ellipse blanking in blanking drawing. $R_c$, the important factor of drawing process was able to evaluate properly in designing of product.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.2
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• pp.162-168
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• 2010

This study attempted to clarify the difference in eggshell pigmentation between blue-shelled ducks (BSD) and whiteshelled ducks (WSD). The eggshell pigmentation deposition process is discussed. Ultraviolet spectro-photometer and HPLC were used to determine the biliverdin concentration in the shell gland, uterus liquid and eggshell at 6, 12, 18, 20, 23.5 h post-oviposition. The biliverdin concentration in the eggshell and uterus fluid showed significant differences between BSD and WSD, but not in the shell gland. The heme oxygenase activity in the shell gland of both kinds of ducks remained mostly constant during the ovulatory cycle with no variation. The assay of exogenous biliverdin injection into the shell gland antrum in the WSD indicated that exogenous biliverdin could be deposited continuously into the eggshell until the source was exhausted. A layer-by-layer dissolution assay was used to examine the eggshell pigment deposition process. The biliverdin concentration in the first to sixth layers of the eggshell in the BSD was significantly higher than that in the white-shelled counterpart. The blue pigment concentration increased persistently from the 6th layer to the $1^{st}$ layer. The BSD eggshells did not accumulate a large quantity of biliverdin in the most external layer. They tended to increase the deposition layer by layer. Our results demonstrated that different BSD and WSD eggshell colors were influenced by the amount of biliverdin in the uterus fluid and not determined by the amount of biliverdin in the shell gland. This implies the existence of a mechanism that controls biliverdin transportation from the shell gland into the uterus fluid, thereby playing a key role in regulating duck eggshell color.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.259-266
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• 2002

The egg shell membrane degrading isolated from soil was identified as Bacillus licheniformis by 16S rDNA identification method. A keratinase was isolated from the Baciilu licheniformis culture. DEAE-cellulose ion-exchange and Sephadex C-75 gel chromatograhies were used to purify the enzyme. The specific activity was increased 17.3-fold by the purification procedures. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis and Sephadex G-75 chromatography indicated that the purified keratinase was monomeric and had a molecular weight of 65 kDa. The enzyme showed optimum activity at pH 9.0, and was stable above pH 9.0. The optimum temperature was 50$\^{C}$ and the enzyme was stable in the temperature ranges from 20$\^{C}$ to 50t. By the addition of 1 mM and 10 mM FeSO4, the activities of the enzyme were increased to 111$\pm$4.6% and 133$\pm$3.79%, respectively. The keratinase was an alkaline serine pretense because it was inhibited only by phenylmethylsulfonylfluorice (PMSF).