• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.7
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• pp.1471-1477
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• 2003

In order to realize the Gbps VPN system, however, newer and more advanced technologies are required to enable wire-rate processing across a wide range of functions and layers. While it is generally accepted that a software soluTion on general-purpose processors cannot scale to process these functionsa wire rate, the KEY POINT is that a software solution on general-purpose processors is the most practical way by which these security allocationscan be developed. Many of these security functions require application layer processing on the content of the packets, and the very nature of application layer software development is characterized by relatively large code size with a high need for portability an flexibility. We have analysed the consideration and specification for realizing Gbps VPN system. from this work. we can obtain a technology of originality.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.3
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• pp.206-213
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• 2000

The microstructure and electrical properties of Pr$_{6}$/O sub 11/-Based ZnO varistors with Nd$_2$O$_3$ was doped in the range of 0.0 to 2.0 mol% were investigated. Most of the added Nd$_2$O$_3$were segregated at the nodal points and grain boundaries and were found to form the Nd-rich phase. In addition the bulk intergranular layer at the grain boundaries and nodal points was consisted of Nd-rich phase and Pr-rich phase. the average grain size was decreased in the range of 7.8 to 5.6${\mu}{\textrm}{m}$ with increasing Nd$_{2}$/O sub 3/ additive content. The nonlinearity of ZnO varistors sintered at 130$0^{\circ}C$ was much more excellent than that at 135$0^{\circ}C$ ZnO varistors doped with 1.0mol% Nd$_{2}$/O sub 3/ exhibited the best nonlinearity. which is 65.2 in the nonlinear exponent and 4.5$\mu$A in the leakage current. Consequently. it is estimated that Pr$_{6}$/O sub 11/ -based ZnO varistors doped with 1.0 mol% Nd$_{2}$/O sub 3/ are to be sufficiently used as basic composition to fabricate good varistors in the future.ure.

• Journal of Surface Science and Engineering
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• v.42 no.4
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• pp.157-160
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• 2009

Many fundamental studies have been carried out regarding waste water and hazardous gas treatments technologies using the photolysis effect of $TiO_2$. However, a permanent use of $TiO_2$ particles immobilized using organic or organic-inorganic binders is impossible. In this study, Ni-$TiO_2$ composite coating was produced by electroless plating to trap $TiO_2$ particles in the Ni coating layer. The electroless plating was performed in the bath solutions with three different concentrations of $TiO_2$ particles : 10 g/l, 20 g/l, and 40 g/l. The surface and photolytic characteristics of the coating layer was investigated by the use of SEM, a scratch tester, and an UV-Visible spectrophotometer. The results showed that the amounts of immobilized $TiO_2$ particles and the photolytic rate of the coating increased with the initial content of $TiO_2$ particles in the electroless bath. In addition, the photolytic rate of the Ni-$TiO_2$ composite coating was remarkably promoted by etching process in 10% HCl solution.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.7
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• pp.573-578
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• 2003

Low temperature selective epitaxial growth of Si and SiGe has been obtained using an industrial single wafer chemical vapor deposition module operating at reduced pressure. Epitaxial Si and heteroepitaxial SiGe deposition with Ge content about 20 % has been studied as extrinsic base for self-aligned heterojunction bipolar transistors(HBTs), which helps to reduce the parasitic resistance to obtain higher maximum oscillation frequencies(f$\_$max/). The dependence of Si and SiGe deposition rates on exposed windows and their evolution with the addition of HCl to the gas mixture are investigated. SiH$_2$Cl$_2$ was used as the source of Si SEG(Selective Epitaxial Growth) and GeH$_4$ was added to grow SiGe SEG. The addition of HCl into the gas mixture allows increasing an incubation time even low growth temperature of 675∼725$^{\circ}C$. In addition, the selectivity is enhanced for the SiGe alloy and it was proposed that the incubation time for the polycrystalline deposit on the oxide is increased probably due to GeO formation. On the other hand, when only SiGe SEG(Selective Epitaxial Growth) layer is used for extrinsic base, it shows a higher sheet resistance with Ti-silicide because of Ge segregation to the interface, but in case of Si or Si/SiGe SEG layer, the sheet resistance is decreased up to 70 %.

• The Korean Journal of Quaternary Research
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• v.23 no.1
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• pp.1-24
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• 2009

Paleosol layers lying on top of the terrace in Jeongdongjin area appear to have been deposited under generally well-drained condition with periodic waterlogging. From a 4.5m-long profile observed, a total of 6 stratigraphic units were identified. Grain-size analysis indicates the dominance of silty and clay materials with some portions with high sand content. Major mineralogical elements are quartz, feldspar, mica and chlorite. Geo-chemical composition shows little change throughout the stratigraphy with some fluctuation in chemical weathering index. Marked increase in magnetic susceptibility is recognizable where stratigraphic unit changes. Soil- wedge layer is developed around 50cm below the surface with concentration of grains of AT tephra (c. 25,000 BP). An OSL date of c. 110,000 BP was obtained from a sand layer lying below the paleosol.

• Polymer(Korea)
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• v.26 no.5
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• pp.623-633
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• 2002

The flame retardant and thermal properties of ortho-cresol novolac (OCN) and biphenyl epoxy blends containing red-phosphorus were investigated. For five types of compounds designed with the volume ratio of OCN and biphenyl epoxy, thermal properties were analysed by TGA or DTC, and flame retardancy effectiveness was estimated through UL-94V test. While the flame retardant and thermal properties were improved with the content of filler and red-phosphorus, the excessive amount of red-phosphorus caused to deteriorate those properties. Using the blends of OCN/biphenyl rather than pure OCN or biphenyl epoxy as a matrix the flame retardancy of composites could be improved by the synergic effects of high thermal resistance of OCN and intumescent property of biphenyl. The flame retardant me chanism of epoxy compound containing red-phosphorus could be thought of the heat-insulating effect of intumescent char-layer formed in the surface of composites.

• Korean Journal of Poultry Science
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• v.21 no.4
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• pp.249-256
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• 1994

This study was conducted to investigate the effects of the addition of varied levels of NaCI and phosphates to the breast meat of spent layers(2 \pm 0.2 kg), which were stabilized for over 24 h before slaughter, on the protein extractability, thiobarbituric acid(TBA) and volatile basic nitrogen (VBN). Within 1 h after slaughter, breast meat was removed and treated with NaCI(0, 1, 2, 3%) and phosphates(0.25% and 0.5%) using a hot-salted method. The breast meat samples were stored at 4\pm$1^{\circ}C$ for 3 d. The results obtained were summarized as follows. 1. Soluble protein contents of salt-treated groups were significantly higher than that of control (P<0.05) and showed a positive relationship with the levels of salt. At a constant level of NaCI, the soluble protein content was proportionately elevated by the levels of phosphates (P<0.05). It decreased significantly in both control and salt-treated groups during storage (P<0.05). 2. TBA values of salt-treated groups were significantly higher than that of control(P<0.05) and showed a positive relationship with the levels of salt. At a constant level of NaCI, TBA values in 0.5% phosphates treatment groups were significantly lower than that in 0.25%(P<0.05). It increased significantly in both control and salt-treated groups during storage(P<0.05). 3. VBN values of salt-treated groups were significantly lower than that of control(P<0.05) They increased significantly by the salt treatment for the first day of storage(P<0.05), but not from the second day of storage. VBN values in both control and salt-treated groups were significantly increased during storage(P<0.05). After the first day of storage and at the same level of NaCI, no significant difference in VBN value was observed between the two levels of phosphates.

• Korean Journal of Metals and Materials
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• v.50 no.2
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• pp.164-170
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• 2012

Nanotubular structure formation on the Ti-6Al-4V and Ti-Ta alloy surfaces by electrochemical methods has been studied using the anodizing method. A nanotube layer was formed on Ti alloys in 1.0 M $H_3PO_4$ electrolyte with small additions of $F^-$ ions. The nanotube nucleation and growth of the ${\alpha}$-phase and ${\beta}$-phase appeared differently, and showed different morphology for Cp-Ti, Ti-6Al-4V and Ti-Ta alloys. In the ${\alpha}$-phase of Cp-Ti and martensite ${\alpha}^{\prime}$ and in the ${\alpha}^{{\prime}{\prime}}$ and ${\beta}$-phase of the Ti-Ta alloy, the nanotube showed a clearly highly ordered $TiO_2$ layer. In the case of the Ti-Ta alloy, the pore size of the nanotube was smaller than that of the Cp-Ti due to the ${\beta}$-stabilizing Ta element. In the case of the Ti-6Al-4V alloy, the ${\alpha}$-phase showed a stable porous structure; the ${\beta}$-phase was dissolved entirely. The nanotube with two-size scale and high order showed itself on Ti-Ta alloys with increasing Ta content.

• Journal of Sericultural and Entomological Science
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• v.28 no.1
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• pp.37-42
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• 1986

The experiment was carried out to investigate the effects of juvenile hormone analogue on changes of protein and amino acids in haemolymph of silkworm larva. Juvenile hormone analogue was topically administered to larvae at dose of 1$\mu\textrm{g}$ 10$\mu\textrm{g}$ per gm of body weight at 60hr. of the 5th instar. The results obtained were as follows ; 1. Larval duration of the fifth instar was extended about 1 day by JHA-1 and 4 days by JHA-10 as compared with the control. 2. Cocoon weight and cocoon layer weight by topical application of JHA were heavier than those of the control, but cocoon layer ratio was decreased in JHA-10 to the exclusion of JHA-1. 3. The concentration of haemolymph protein during the fifth instar was increased remarkably by the JHA application. 4. The total content of amino acids in haemolymph proteins of JHA-10 approximately doubled that of the control, with the conspicuous increase of glycine and arginine level.

• Computers and Concrete
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• v.23 no.3
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• pp.161-170
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• 2019

This paper aims at presenting a numerical method for estimating the elastic modulus of recycled concrete with crushed aggregates. In the method, polygonal aggregates following a given sieve curve are generated, and placed into a square simulation element with the aid of the periodic boundary condition and the overlap criterion of two polygonal aggregates. The mesostructure of recycled concrete is reconstructed by embedding an old interfacial transition zone (ITZ) layer inside each recycled aggregate and by coating all the aggregates with a new ITZ layer. The square simulation element is discretized into a regular grid and a representative point is selected from each sub-element. The iterative method is combined with the fast Fourier transform to evaluate the elastic modulus of recycled concrete. After the validity of the numerical method is verified with experimental results, a sensitivity analysis is conducted to evaluate the effects of key factors on the elastic modulus of recycled concrete. Numerical results show that the elastic modulus of recycled concrete increases with the increase of the total aggregate content and the elastic moduli of old and new ITZ but decreases with increasing the replacement ratio of recycled aggregate and the thicknesses of old and new ITZ. It is also shown that, for a replacement ratio of recycled aggregate smaller than 0.3, the elastic modulus of recycled concrete is reduced by no more than 10%.