• Elastomers and Composites
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• v.36 no.1
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• pp.14-21
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• 2001

To increase the properties of EVA foam such as tensile strength, rebound resilience, and compression set, ethylene-1-butene copolymer (EtBC) was blended with EVA. After that crosslink characteristics of the blends and cell structures and mechanical properties of the foam were studied. As the amount of EtBC increased in EVA/EtBC blends, torque values of oscillating disc rheometer(ODR) increased and the foaming ratio decreased because the viscosity and crosslink density of EVA/EtBC blends increased. Foaming ratio and cell size of the foam increased by increasing the amount of foaming agent. When compared the mechanical properties of the foam which have same densities, tensile strength, rebound resilience, and compression set properties of the foam were improved by increasing the amount of EtBC in the EVA/EtBC blends.

• Korean Journal of Veterinary Research
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• v.35 no.4
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• pp.671-681
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• 1995

This study was attempted to investigate the topographical distribution, shape and immunoreactivity of growth hormone-releasing factor(GRF)- and somatostatin(SOM)-immunoreactive neurons in the hypothalamus of the Korean squirrels(Sciurus vulgalis coreae). For the light microscopical examination of immunohistochemistry, the brains were fixed with 4% paraformaldehyde solution by means of intracardiac perfusion. And the frozen sections($40{\mu}m$ thick) were stained immunohistochemically by ABC method. Distribution of GRF immunoreactive neurons($12-17{\mu}m$) was highest in the paraventricular nucleus, moderate in the periventricular and supraoptic nuclei, and low in the arcuate nucleus and lateral hypothalamic area. Their immunoreactive fibers were found very high in the median eminence, moderately in the supraoptic, paraventricular and periventricular nuclei, and low in the arcuate nucleus and lateral hypothalamic area. SOM immunoreactive perikarya($14-18{\mu}m$) were found moderately in the periventricular nucleus near the subependymal layer of the third ventricle, and low in the arcuate and suprachiasmatic nuclei. SOM immunoreactive fibers were found high in the median eminence, and moderately or low in the arcuate and periventricular nuclei.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.39 no.2
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• pp.69-80
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• 2002

In this paper, signed-rank based nonparametric detectors are used for direct sequence code division multiple access pseudo-noise code acquisition systems in frequency-selective Rician fading channels. We first derive the locally optimum rank detector, and then propose the locally suboptimum rank (LSR) and k-th order modified signed-rank (MSRk) detectors using approximate score functions. We compare the serial and hybrid parallel double-dwell schemes using the LSR and MSRk detectors with those using the conventional squared-sum (SS) using the cell averaging constant false alarm rate processor and modified sign detectors. From the simulation results, it is shown that the LSR and MSRk detectors perform better than the SS detector using the cell averaging constant false alarm rate processor.

• The Journal of Dong Guk Oriental Medicine
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• v.2 no.2
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• pp.1-15
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• 1993

The purpose of this study is to observe the effect of Woogyuyem on serum reaction and hepatic tissue in Cyclosporin A treated rats. In this study, the experimental rats divided two group(Control group and Sample group). Under the same condition, both control group and sample group were injected to abdomen with Cyclosporin A for 7days. And then, control group were administered water, sample group were administered Woogy-uyeum for 300days. The change of transaminase and bile acid and SOD activity in blood serum, hepatic tissue were measured at 3rd, 7th, 15th, 30th day. The obtained results are summarised as follows : 1. In the change of SGOT contents, as compared with control group, sample group was significantly decreased at 7th and 15th day. 2. In the. change of SGPT contents, as compared with control group, sample group was significantly decreased at 15th day. 3. In the change of serum bile acid contents, as compared with control group, sample group was significantly decreased at 7th and 15th day. 4. In the change of serum SOD activity, as compared with control group, sample group was significantly increased at 15th and 30th day. 5. In the change of hepatic tissue, as compared with control group, the vacuolation of hepatocytes in the sample group was reduced, the liver plates were reconstructed, and the epitheriai cell wasn't destructed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.4
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• pp.675-683
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• 2009

RC6 which has different algorithm of encryption and decryption has been proposed to have the same algorithm between encryption and decryption through inserting symmetry layer using simple rotate and logical operation. That means the half of whole RC6 round uses encryption algorithm and the rest of it uses decryption one and symmetry layer has been put into the middle of encryption and decryption. The proposed RC6 algorithm has no difference with the original one in the speed of process. However it is quite safe because by inserting symmetry layer the path of high probability which is needed for differential and linear analysis is cut off so that it is hard to be analyzed. The proposed symmetry layer algorithm can be easily applied to the algorithm which has different encryption and decryption and make it same, and it can be good idea to be used to design a new block cipher algorithm.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.5
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• pp.358-366
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• 2015

In this study, a nondestructive test (NDT) is performed to inspect the optimal design of a ground tracked combat vehicle for self-propelled artillery, tank, and armored vehicles. The minimum qualification required for personnel performing the NDT of a ground tracked combat vehicle was initially established in US military standards, and then applied to the Korean defense specifications to develop a ground tracked combat vehicle. However, the qualification standards of an NDT inspector have been integrated into NAS410 through the military and commercial specifications unification project that were applied in the existing aerospace/defense industry public standard. The design method for this study was verified by applying the optimal design to the liquid penetrant testing Al forging used in self-propelled artillery. This confirmed the reliability and soundness of the product.

• Korean Journal of Ecology and Environment
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• v.38 no.3 s.113
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• pp.334-340
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• 2005

The chemical forms of Cd, Cu, Pb, and Zn were analysed by sequential extraction technique to evaluate the effects of drying and heating of dredged sediments from Lake Chungcho. The most abundant fraction of Cd, Cu, and Zn in the wet and untreated sediment was organic/sulfidic fraction that is state in reducing environment such as the bottom condition of Lake Chungcho, while Pb dominated in residual fraction. This means that the source of Cd, Cu, and Zn in the Chungcho lake sediment is related to the organic degradation and Pb to the erosion from surrounding rocks. With drying and oxidation by dredging, heating treatment, and disposal of the lake sediment, the chemical forms of studied metals changed greatly from organic/sulfidic fraction to adsorbed and reducible fractions which are more labile in oxygenated environment. Organic/sulfidic fraction of Cd, Cu and Pb in the wet sediment was transformed with drying and heating treatments to the labile ones like adsorbed and reducible fraction, but Zn to carbonate and reducible fraction. Heating of the sediment at $320^{\circ}C$ greatly increased the labile fraction of Cd and Cu, while that at $105^{\circ}C$ for Pb and Zn. It is believed that the increase in labile forms of heavy metals in the sediments by drying and heating is caused by the contact with oxygen during drying and heating and by the increase of pH of the pore water at the expense of organic/sulfidic fraction. It is concluded that the drying and oxidation currently used in the treatment of dredged sediment can increase labile forms of heavy metals in the sediment, and the potential of the metal availability from the sediment.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.6
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• pp.892-897
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• 2005

Macrophage colony-stimulating factor (M-CSF) is a growth factor required for growth and differentiation of mononuclear phagocyte lineage. Total and 16 poly (A) mRNA of bovine M-CSF were isolated from healthy bovine peripheral mononuclear cells stimulated by phobol 12-myristste 13-acetate (TPA). The more compatible cultured mononuclear cells were 5${\times}$10/ml for RNA isolation. TPA-activated mononuclear cells increased the level of M-CSF-mRNA more than concanavalin A (Con A) and lipopolysaccharide (LPS). The optimal analysis of reverse transcriptase-polymerase chain reaction (RT-PCR) for14 Macrophage colonystimulating factor (M-CSF) as a growth factor required for bovine M-CSF was denaturation at 94$^{\circ}C$ for 1 minute, annealing at 57$^{\circ}C$ for 1 minute, extension at 72$^{\circ}C$ for 1 minute for 30 cycles. The size of cDNA of bovine M-CSF by RT-PCR was 774 base pairs. A 774 base pairs cDNA encoding bovine M-CSF was synthesized by reverse transcriptase polymerase chain reaction (RT-PCR). Ligated cDNA was transformed to competent cells and then plasmid isolation and digestion was performed. Molecular cloning and sequencing were performed for cDNA of bovine M-CSF. The size of cloned cDNA of bovine M-CSF was 774base pairs. The homology of base sequence and amino acid sequence was 88% and 86% compared with known human M-CSF, respectively. From a high degree of sequence similarity, the obtained cDNA of bovine M-CSF is thought be a specific gene of bovine M-CSF.

• Journal of the Korean Society for Heat Treatment
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• v.19 no.4
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• pp.200-207
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• 2006

In addition to the basic properties of the base and top coating agents, corrosion resistance of non-chrome magni 565 coating and characteristics of coating film when coated to steel substrate were studied. The system had a good wettability at room temperature. Moreover, both the contact angle and surface tension were affected little by the viscosity of coating agent and surface roughness of the steel substrate. And the samples coated with optimal conditions showed a great corrosion resistance in salt spray test with 1500 hours or longer of initial appearance time of rust. The coating film was composed of overlapping layer of zinc and aluminium flakes, and the thickness of base coat increased with an increase of base coat viscosity. Based on the C-F peaks of 1,1-Difluoroethaen homo-polymer, it was thought that the base coat was an inorganic polymer bond layer. Meanwhile, the top coat showed C-F peaks of polytetrafluoroethylene with C-H peaks of phenol in FT-IR analysis. From the lower weight loss of base coat in TG analysis, it was thought that cross linking density of base coat was larger than that of top coat. It was thought that the small exothermic reactions observed in DSC curves were due to the thermosetting resins contained in the coating agents. Compared to the non-coated specimen, the coated sample showed more higher polarization resistance and corrosion potential with lower corrosion current density.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.247-250
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• 2008

RC6 which has different algorithm of encryption and decryption has been implemented to have the same algorithm between encryption' and decryption though inserting symmetry layer using simple rotate and logical operation. That means the half of whole RC6 round uses encryption algorithm and the rest of it uses decryption one and symmetry layer has been put into the middle of encryption and decryption. The proposed RC6 algorithm has no difference with the original one in the speed of process. However it is quite safe because by inserting symmetry layer the path of high probability which is needed for differential and linear analysis is cut oft so that it is hard to be analyzed. The proposed algorithm can be easily applied to the algorithm which has different encryption and decryption an make it same, and it can be good idea to be used to design a new block cipher algorithm.