• Korean journal of food and cookery science
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• v.6 no.4 s.13
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• pp.21-26
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• 1990

This study was undertaken to determine the content of calcium, phosphorus, and magnesium in Korean styled Sagol bone stok (beef leg bone stock) deffering in cooking utensil, cooking method, and cooking time. Cooking was started in cold water and boiling water using stainless steel and aluminium cooker. In the changes of mineral contests in Sagol bone stock at cooking time from 2 to 12 hours, Ca, P, and Mg contents increased significantly by the cooking time in stainless steel and aluminium cooker but Ca and P contents decreased slightly during 12 hours in steel cooker. But Ca, P, and Mg contents of the Sagol bone stock were not significantly different between cooking utensil and method. The extracting rate of Ca, P, and Mg of the Sagol bone stock were $0.02{\sim}0.05%$, $0.2{\sim}0.7%$, and $0.1{\sim}1.0%$, respectively. The extracting rate of Ca was positively correlated with that of Mg (r=0.8872, p<0.001).

• Transactions of Materials Processing
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• v.4 no.3
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• pp.214-221
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• 1995

In the paper, we have proposed a new method to determine the initial billet for the forged products using a function approximation in the neural network. The architecture of neural network is a three-layer neural network and the back propagation algorithm is employed to train the network. By utilizing the ability of function approximation of a neural network, an optimal billet is determined by applying the nonlinear mathematical relationship between the aspect ratios in the initial billet and the final products. The amount of incomplete filling in the die is measured by the rigid-plastic finite element method. The neural network is trained with the initial billet aspect ratios and those of the unfilled volumes. After learning, the system is able to predict the filling regions which are exactly the same or slightly different to the results of finite element simulation. This new method is applied to find the optimal billet size for the plane strain rib-web product in cold forging. This would reduce the number of finite element simulation for determining the optimal billet size of forging product, further it is usefully adapted to physical modeling for the forging design.

• The Journal of Internal Korean Medicine
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• v.20 no.1
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• pp.143-152
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• 1999

Dansam, the root of Salvia miltiorrhiza Bge, (Labiatae), has a bitter taste and a slightly 'cold' property, and is nontoxic. In the present study, effect of Dansam on nitric oxide (NO) generation from peritoneal macrophags was examined. Dansam had no effect on NO generation by itself, whereas recombinant interferon-${\gamma}\;(rIFN-{\gamma})$ alone had modest activity. When Dansam was used in combination with $rIFN-{\gamma}$, there was a marked cooperative induction of NO generation in a dose-dependent manner, The optimal effect of Dansam on NO generation was shown at 6 hr after treatment with $rIFN-{\gamma}$. Furthermore, the effect of Dansam was mainly dependent on Dansam-induced tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$ secretion. These results suggest that Dansam induces NO generation from macrophages by the result of Dansam-induced $TNF-{\alpha}$ secretion.

• Journal of Conservation Science
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• v.1 no.1 s.1
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• pp.12-26
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• 1992

Ilsan peat-bed site, newly constructed city area, is located at the northern part of Seoul. This site is situated near the mouth of Han river, which flows through central Korea. Many fossil woods were excavated from this site, and surveyed the wood anatomical features. Totally 90 specimens were identified into 10 species including two roots and five barks which were not identified in detail. Alnus japonica and A. maxmowiczii are the most common and occupied 26. 7%, 34.4% of the total specimen number respectively, and then other species which excavated from Ilsan area are follows : Fraxinus rhynchophylla(18.9%), Lepido-balanus spp.(3.3%), Maackia amurensis(2.2%), Diospyros spp.(2.2%), Juglans mandshrica(1.1%), Prunophora spp.(1.1%), Malus or Pyrus spp.(1.1%), Rhamnus spp.(1.1%). Among the identified species there are fairly some species growing in the central - or northern temperate zone, such as A. maxmowiczii, F. rhynchophylla, Lepidobalanus spp., M. amurnsis, J. mandshurica, Rhumnus spp. Therefore, it can be estimated that the former temperature of Ilsan area was same or slightly cold than today. The species bearing fruit for food as .J, mandshunca, Diospyros spp., Prunophora spp., Mulus or Pyrus spp. were regarded as artificially planting trees, because they do not grow together in the same site.

• Journal of Powder Materials
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• v.17 no.6
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• pp.477-481
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• 2010

Cu-Sn based alloys were manufactured by gas atomization spray casting route in order to achieve a fine scale microstructure and a high tensile strength. The spray cast Cu-10Sn-2Ni-0.2Si alloy had an equiaxed grain microstructure, with no formation of brittle ${\delta}-Cu_{41}Sn_{11}$ phase. Aging treatment promoted the precipitation of finely distributed particles corresponding to ${\delta}-Ni_2Si$ intermetallic phase throughout the $\alpha$-(CuSn) matrix. The cold-rolled Cu-Sn-Ni-Si alloy had a very high tensile strength of 1200 MPa and an elongation of 5%. Subsequent aging treatment at $450^{\circ}C$ for 1h slightly reduced the tensile strength to 700 MPa and remarkably increased the elongation up to 30%. This result has been explained by coarsening the precipitates due to over aging and reducing the dislocation density due to annealing effects.

• Transactions of Materials Processing
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• v.30 no.6
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• pp.301-305
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• 2021

The role of Nb addition in the tension and corrosion responses of ferrite-based stainless-steel sheets processed by cold-rolling and annealing treatment at 1173 °K was studied to evaluate the possibility for commercialization. For this purpose, the grain sizes in the samples with and without Nb content were controlled to be reasonably identical by utilizing different heat treatments within the specific range for 60 seconds. The corrosion properties of both samples were evaluated based on the analysis of polarization curves. Room-temperature tension testing showed that the strength of the sample with Nb was much higher than that without Nb whereas the elongation of the sample with Nb was slightly lower than that without Nb. The polarization curves revealed that the addition of Nb contributed to the significant improvement in protective capabilities. We thought that such combinational behavior was mainly due to the formation of niobium carbides found in the ferritic matrix.

• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2304-2311
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• 2021

The dislocation density in strain-hardened Alloy 690 was analyzed using scanning transmission electron microscopy (STEM) to study the relationship between the local plastic strain and susceptibility to primary water stress corrosion cracking (PWSCC) in nuclear power plants. The test material was cold-rolled at various thickness reduction ratios from 10% to 40% to simulate the strain-hardening condition of plant components. The dislocation densities were measured at grain boundaries (GB) and in grain interiors of strain-hardened specimens from STEM images. The dislocation density in the grain interior monotonically increased as the strain-hardening proceeded, while the dislocation density at the GB increased with strain-hardening up to 20% but slightly decreases upon further deformation to 40%. The decreased dislocation density at the GB was attributed to the formation of deformation twins. After the PWSCC growth test of strain-hardened Alloy 690, the fraction of intergranular (IG) fracture was obtained from fractography. In contrast to the change in the dislocation density with strain-hardening, the fraction of IG fracture increased remarkably when strain-hardened over 20%. From the results, it was suggested that the PWSCC growth behavior of strain-hardened Alloy 690 not only depends on the dislocation density, but also on the microstructural defects at the GB.

• Journal of Animal Science and Technology
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• v.61 no.1
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• pp.47-53
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• 2019

This study was performed to evaluate the microbial and temperature changes of boxed beef during transport and distribution under vacuum and modified atmosphere packaging (MAP), and to compare between excision and swab sampling for 15 days. The top round and striploin (quality grade 1) from Hanwoo steers at 2 days post-slaughter were obtained from a local meat processing plants and chilled at $4{\pm}2^{\circ}C$ in a cold room. The boxes were transported under refrigeration ($4{\pm}2^{\circ}C$) to the laboratory within half an hour. Vacuum and MAP packs were subsequently taken out from cool boxes, and microbiological examinations were carried out at 0, 6, 12, and 24 h of storage time. MAP was more effective than vacuum packaging for the inhibition of total aerobic, lactic acid bacteria and Pseudomonas (p < 0.05). Microbial loads of swab methods were slightly lower than those of excision ones (p < 0.05). The results of this study could be utilized by meat consumers in future studies as well as by manufacturers to determine the ideal storage conditions for cool boxed meat, thus ensuring reduced economic losses due to spoilage.

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.308-313
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• 2018

During a survey of marine algal flora, a red algal species was collected from Giseong, Uljin located on the eastern coast of Korea. This species has the generic features of Cryptonemia belonging to Halymeniaceae, and is characterized by the presence of erect foliose thalli arising from a discoid holdfast, somewhat fan-shaped blade with an evanescent midrib at the base, narrow main axes with blade-like wings of slightly undulate margin, a perennial stalk, and entwined filamentous medulla with refractive stellate cells. In a phylogenetic tree based on rbcL sequence, the Korean alga nests in the same clade with C. lomation from France and C. seminervis from Spain. Genetic divergence among the sequences within the clade was not recognized thus suggesting that both the species are conspecific. The name C. lomation considered to be valid nomenclaturally is accepted for the entity. Based on the morphological and molecular analyses, the Korean alga is identified as C. lomation, originally described from Italy. This confirms the occurrence of C. lomation in Korea. The species appears to be distributed in the temperate region influenced more or less by the North Korea Cold Current.

• Journal of The Korean Astronomical Society
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• v.26 no.1
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• pp.73-78
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• 1993

We have mapped the $C_3H_2\;2_{12}-1_{01}$ transition line toward the Sgr A molecular cloud on a 1' grid spacing and derived $C_3H_2$ column densities of $3\~7\times10^{14}\;cm^{-2}$ for molecular clouds of Sgr A. The fractional abundances of $C_3H_2$ relative to $H_2$ are obtained to be $3\~6\times10^{-9}$, which are slightly lower than that for the cold dark cloud TMC-1 but are enhanced by factors of 5-60 compared to those for Sgr B2 and the Orion extended ridge. We also estimate from the $C_3H_2$ column densities total masses of $\~10^6\; M_\bigodot$ for two clouds (M - 0.13 - 0.08 and M - 0.02 - 0.07), which are thought to be close to the virial equilibrium. We suggest that the large abundance of $C_3H_2$ in Sgr A may be partly due to the activities of the Galactic center.