• 한국안전학회지
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• 제10권1호
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• pp.28-34
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• 1995

To improve fire proofing characteristics of protective coating using ternary soluble silicate from two component mixture, the method of reducing solubility, increasing intumescence and protection time have been studied. Intumescence and solubility of ternary silicate mixtures were dependent on many kinds of water release and the strength of cation cross-links between polysilicate particles. Especially the effect of additive, for example, corn starch was investigated. However the solubility of ternary mixture is decrease in order of Na$^{+}$ >K$^{+}$ >Li$^{+}$, and the magnitute of intumescence is increased $K^{+}$ >Na$^{+}$ >Li$^{+}$.}$ +/.

• The Journal of Korean Physical Therapy
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• 제14권4호
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• pp.412-422
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• 2002

The use of biochemical markers of bone turnover may be particular interest in the investigation of bone disorders with osteoporosis. Serum osteocalcin(OC), total alkaline phosphatase and procollagen C, reflecting bone formation, and urinary pyridinium cross-links excretion, reflecting bone reabsorption have been measured in hyperthyroidism, postmenopause women, after testosterone supplementation, androgen, testosterone and estrogen deficiency, bone mineral density degree, age duration. Bone marks which is reflect to metabolic bone disorders are biochemical indices method to measure enzyme activity about bone formation, bone absorption and bone components in blood or urine. Bone metabolism biochemical marks are correlated with osteophorotic agents and also represent significantly different between bone mineral density and bone biochemical marks. Therefore if we develope and use bone metabolism marks which have higher sensitivity and specificity in bone formation and bone absorption, I think that these bone biochemical marks can have utility in the clinical application to predict osteoporosis risk group, bone loss, bone fracture and response degree to treatment of osteoporosis risk groups.

• 한국의류학회지
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• 제28권9_10호
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• pp.1265-1272
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• 2004

The purpose of this study is to develope wrinkle recovery property, DP rating of Tencel by using BTCA(1,2,3,4-butanetetracarboxylic acid) and MgCl$_2$ that does not make water pollution. The adoptable condition to improve the wrinkle resistance and DP rating was determined 10％ BTCA(o.w.f), 3％ catalyst(o.w.f), 0.5％ softener(o.w.f), 5min padding time, 150$^{\circ}C$ curing temperature, 2min curing time and pH 2.7. It was proven that ester groups were formed and cross-links increased by treating Tencel with BTCA. By XPS diffraction, Tencel treatment using BTCA was proved not to affect crystal formation.

• Elastomers and Composites
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• 제27권4호
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• pp.255-261
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• 1992

Chlorosulfonated polyethylene(CSM) was moisture-cure after treating them with silane coupling agents such as ${\gamma}-mercapto$ propyl trimethoxy silane, ${\gamma}-glycidoxy$ propyl triethoxy silane and methyl triethoxy silane, 3-(trimethoxy silyl) propyl methacrylate and 3-thiocyanopropyl triethoxy silane. The cure reaction is composed two steps. The first is the reaction between chlorosulfonyl groups of CSM and silane coupling agents. The second is the formation of cross-links which are siloxane linkage. The linkage is formed by the condensation of silanol groups which are produced by the hydrolysis of alkoxysilyl groups. CSM was mixed with MPS etc., and dilaurate dilaurate as catalyst on two open mill and the compounds were lured in hot water at $70^{\circ}C$ Physical properties of moisture-cured CSM was measured. CSM was effectively moisture-cured and r-mercapto propyl trimethoxy silane and r-glycidoxy propyl trimethoxy silane were capable of the vulcanizing agents.

• Structural Engineering and Mechanics
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• 제42권1호
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• pp.55-72
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• 2012

Precast-cast insitu concrete bridge construction is widely practiced for small to medium span structures. These bridges consist of precast pre-stressed concrete beams of various cross-sections with a cast in-situ reinforced concrete slab. The connection between the beams and the slab is via shear links often included during the manufacturing process of the beams. This form of construction is attractive as it provides for standardisation, reduced formwork and construction time. The assessment of the integrity of shear connectors in existing bridges is a major challenge. A procedure for assessment of shear connectors based on vibration testing and finite element model updating is proposed. The technique is applied successfully to a scaled model bridge model and an existing bridge structure.

• 한국컴퓨터정보학회논문지
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• 제22권6호
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• pp.25-32
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• 2017

We are living in networks which are regarded as a society. However, it is difficult to designate a specific position or the impact over sociological relationships and virtual links. In this paper, we conceptualize two themes of the network as Physical Network and Virtual Network, and observe their cross-network effects. New concept called Networked Community (NC) is then introduced to walk through both PN and VN by using the element of connections say connectivity feature. Through modeling NC by the theme of network transposition and egocentric network, we try to comprehend all possible networks for detecting the problems and solutions by using both sides' idea. Experimental results show that we can model real-world problems and then analyze them through NC by measurable and structural manner.

• 한국안전학회지
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• 제8권2호
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• pp.30-38
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• 1993

To increase fire proofing characteristics of protective coating based on soluble alkali silicate, silicate coatings were studied on thermal properties, IR spectroscopy, solubility and intumescence. Intumescence and solubility of the samples were dependent on the strength of cationic cross-links between polysilicate particles. The degree of intumescence and solubility decrease K-silicate > Na-silicate > Li-silicate in the order. Especially Si$_2$O$_{5}$ $^{-2}$ crystalline regions were found to exist in Potassium silicate sample. Mixture of two kinds of silicate, for example, Lithium silicate when added to sodium silicate or potassium silicate was find to significantly reduce efflorescence and increase water resistance. This appears to be a result of stronger crosslinking between polysilicate particles by the small lithium cation.

• Current Optics and Photonics
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• 제6권1호
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• pp.86-91
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• 2022

Two-photon fluorescence microscopy was performed on the enamel-dentin junction area of a human tooth using a femtosecond pulsed laser. We obtained a clear image contrast between the bright dentin and dark tubules with the autofluorescence generated from the endogenous fluorophores in dentin. The autofluorescence shows a broad spectrum due to complex cross links between dentinal collagens, which extend from blue to orange wavelengths (470-590 nm), but a gradual autofluorescence loss in photobleaching was observed for a long-term exposure under strong excitation. For increasing excitation power, we found that two-step decay becomes significant in the spectrally integrated autofluorescence.

• Elastomers and Composites
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• 제26권2호
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• pp.115-122
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• 1991

Polychloroprene rubber was moisture-cured after treating them with silane coupling agents such as 3-mercaptopropyltrimethoxysilane(MPS), 3-methacryloxypropyltrimethoxysilane(MAS) and vinyltriethoxysilane(VES), especially MPS. The cure reaction is composed of two steps. The first is the reaction between chlorine atoms of CR and silane coupling agents. The second is the formation of cross-links which are siloxane linkage. The linkage is formed by the condensation of silanol groups which are produced by the hydrolysis of alkoxysilyl groups. The first reaction was kinetically studied and the reactivity of CR to silane coupling agents was determined in previous literature. Crosslinking density and mechanical properties of the moisture-cured elastomer filled with silica or non-filled were studied and the feasibility of this cure system was discussed.

• Animal cells and systems
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• 제9권2호
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• pp.79-85
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• 2005

Oxidized abasic residues arise as a major class of DNA damage by a variety of agents involving free radical attack and oxidation of deoxyribose sugar components. 2-deoxyribonolactone (dL) is a C1'-oxidized abasic lesion implicated in DNA strand scission, mutagenesis, and covalent DNA-protein cross-link (DPC). We show here that mammalian cell-free extract give rise to stable DPC formation that is specifically mediated by dL residue. When a duplex DNA containing dL at the site-specific position was incubated with cell-free extracts of Po ${\beta}-proficient$ and -deficient mouse embryonic fibroblast cells, the formation of major dL-mediated DPC was dependent on the presence of DNA polymerase (Pol) ${\beta}$. Formation of dL-specific DPC was also observed with histones and FEN1 nuclease, although the reactivity in forming dL-mediated DPC was significantly higher with Pol ${\beta}$ than with histones or FEN1. DNA repair assay with a defined DPC revealed that the dL lesion once cross-linked with Pol ${\beta}$ was resistant to nucleotide excision repair activity of cell-free extract. Analysis of nucleotide excision repair utilizing a model DNA substrate containing a (6-4) photoproduct suggested that excision process for DPC was inhibited because of DNA single-strand incision at 5' of the lesion. Consequently DPC mediated by dL lesion may not be readily repaired by DNA excision repair pathway but instead function as unusual DNA damage causing a prolonged DNA strand break and trapping of the major base excision repair enzyme.