• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.1
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• pp.1-8
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• 2011

Introduction: The utility of the C-terminal cross-linking telopeptide test (CTX) as a method for staging Bisphosphonate-related osteonecrosis of the jaws (BRONJ) and its healing process was examined. Materials and Methods: A total 19 patients who were diagnosed with BRONJ underwent a fasted morning CTX test, were enrolled in this study. The serum CTX values ranged from 50 to 630 pg/mL (mean 60). The risk assessment was rated according to the CTX values of the individual patient (minimal risk, ${\geq}$ 150 pg/mL, moderate, 100 to 150 pg/mL, high, ${\leq}$100 pg/mL). The BRONJ scores were then calculated according to the number of BRONJ lesions and their stage. The operation was done as soon as possible, regardless of BORNJ stage. Results: The mean duration of bisphosphonate therapy was 4.1 years. Of the 19 patients, 15, 2 ans 2 received alendronate, risedronate and zoledronate, respecively. Of the 19 patients who underwent a sequestrectomy, saucerization and smoothing, 15 healed after the initial surgery, 1 patient healed after one more surgical procedure, 3 patients did not heal completely but showed improvement in symptoms. Therefore, 17 out of the 19 patients healed completely with complete mucosal coverage and the elimination of pain. The risk assessment using the CTX value and disease severity were not correlated (r=-0.264, P=0.275). In addition, the risk assessment using CTX value and healing after surgery were not correlated (r=-0.147, P=0.547). Conclusion: The serum CTX should be considered carefully by clinicians as part of overall management. Early surgical intervention is of benefit in the treatment of stage II BRONJ.

• Journal of Adhesion and Interface
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• v.9 no.1
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• pp.28-34
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• 2008

This study was used particleboard with urea-formaldehyde resin and cross linking vinyl resin. Manufactured particleboard had high cross linking vinyl resin content that internal bonding strength was low value but flexural strength was increased. For emission test of particleboard using VOC Analyzer, it was confirmed that more cross linking vinyl resin had reduced 4 volatile organic compounds (Toluene, Ethylbenzen, Xylene, Styrene) but also TVOC (Total VOC), 5 VOCs (Benzene, Toluene, Ethylbenzen, Xylene, Styrene) and formaldehyde emissions from manufactured particleboard were also lower emission factor than particleboard with only urea formaldehyde resin.

• Journal of the Microelectronics and Packaging Society
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• v.29 no.4
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• pp.9-14
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• 2022

Silica aerogel is a porous material with a very low density and high specific surface area. Still, its application is limited due to its weak mechanical properties due to structural features. To solve this problem, a method of complexing it with various polymers has been proposed. We synthesized polyimide cross-linked silica aerogel by the sol-gel process to obtain high mechanical properties. Tetraethyl orthosilicate (TEOS) was used as a precursor to make silica aerogel, and 3- aminopropyltriethoxysilane (APTES) was used as a coupling agent for cross-linking polyimide. Polyimide was synthesized using pyromellitic dianhydride and 3,5-diaminobenzoic acid, and mechanical properties were improved by crosslinking polyimide with 10 repeating units in the polyimide chain using the reaction formula ${\frac{n_1}{n_2}}={\frac{n}{n+1}}$ To realize silica aerogel, polyimide having various weight ratios was added before gelation, resulting in a 19-fold or greater increase in maximum compressive strength compared to pure silica aerogel. From this study, an enhancement of silica aerogel could be enhanced through polymer cross-linking bonds.

• Journal of Ocean Engineering and Technology
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• v.13 no.3 s.33
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• pp.3-11
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• 1999

Optimum design of mooring dolphin is numerically investigated. Design optimization problem of moring dolphin is first formulated. Geometry and cross sections of piles are used as design variables. Design objective is the total weight of steel piles of mooring dolphin, and the constraints of stress, penetration depth, lower and upper bounds on design variables are imposed. Based on the design variable linking and fixing, several class of design variations are sought. For the numerical optimization, both PLBA(Pshenichny - Lim - Belegundu - Arora) program and DNCONF subroutine code in IMSL library are used. For a dolphin structure with 20 steel piles, vertical and inclined, optimum designs for different cases are successfully obtained, which can be applied for the mooring of a very large floating structure.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.487-494
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• 2004

Resizing techniques have been recognized as practical methods for drift design of high-rise building since sensitivity analysis and iterative structural analysis are not required in implementation. In the techniques, the amount of material of a memberin a building for resizing is determined in terms of cross-sectional areas and sectional inertia moments as design variables. In this study, five drift design methods are developed by considering design variable linking strategy and fomulating resizing algorithm in terms of material properties of shear walls as a design variable. The developed methods are applied to the drift design of 20-story frame-RC shear wall structure, and then evaluated in the view points of practicality and efficiency.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.85.2-85.2
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• 2010

There is widespread effort to develop polymer membranes in place of Nafion for high temperature polymer electrolyte membrane fuel cell(PEMFC). In our study, SiO2 membranes are arranged by electrospinning method. For impregnation solution, the modified sulfonated poly(ether ether ketone)(SPEEK) polymer is prepared from sulfonation, sulfochlorination, partial reduction and lithiation reaction. The modified polymer is cross-linked with 1,4-diiodobetane in NMP solvent and then blended with Heteropoly acid(HPA). The characterization of membranes is confimed by FT-IR, Thermogravimetry(TGA), water uptake test and single cell performance test for PEMFC, etc. The composite membrane shows satisfactory thermal and mechanical properties. Beside, The membrane exhibits good ion exchange capacity and high proton conductivity. As a result, The composite membrane is promising as an alternative membrane in high temperature PEMFC.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.215-215
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• 2014

Red color light emitting diodes (LEDs) were fabricated using CdSe/CdZnS quantum dots (QDs). During the device fabrication process, oxygen plasma treatment on the ITO surface was performed to improve the interfacial contact between ITO anode and the hole injection layer. CdSe/CdZnS quantum dots were cross-linked to remove their surrounded organic surfactants. The device shows red emission at 622 nm, which is consistent with the dimension of the QDs (band gap=1.99 eV). The luminance shows 6026% improvement compared with that of LEDs fabricated without oxygen plasma treatment and quantum dots cross-linking process. This approach would be useful for the fabrication of high-performance QLEDs with ITO electrode and PEDOT:PSS hole injection layers.

• Korean Membrane Journal
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• v.10 no.1
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• pp.1-7
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• 2008

Polystyrene-co-divinylbenzene (PS-co-DVB) asymmetric membranes were prepared. In order to control their structure and mechanical properties the degree of cross-linking and the composition of casting solution were varied. The rubber added PS-DVB membranes was also prepared to overcome the mechanical limitation of cross-linked membrane, and their mechanical properties were investigated. It was revealed that the concentration of polymer in the casting solution affected the determination of skin formation. When the PS-co-DVB membrane consists of styrene-butadiene (SB) rubber or liquid polybutadiene (PBD), the structures formed showed that the PS content in the PS/DVB system played an important role in determining the porous sublayer structure.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.312-314
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• 2009

We have fabricated pentacene based organic thin film transistors (OTFTs) with formulated poly[4-vinylphenol] (PVP) gate dielectrics. The gate dielectrics is composed of PVP, poly[melamine-coformaldehyde] (PMF) and photo-initiator [1-phenyl-2-hydroxy-2-methylpropane-1-one, Darocur1173]. By adding small amount (1 %) of photo-initiator, the cross-linking temperature is lowered to $115^{\circ}C$, which is lower than general thermal curing reaction temperature of cross-linked PVP (> $180^{\circ}C$). The hysteresis and the leakage current of the OTFTs are also decreased by adding the PMF and the photoinitiator in PVP gate dielectrics.

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1161-1164
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• 1998

The catalytic transformation of sterically bulky tertiary stannane n-Bu3SnH by the Cp2MCl2/Red-Al (M=Ti, Zr, Hf) and M(CO)6 (M=Cr, Mo, W) catalysts yielded two kinds of catenated products: one is a cross-linked polystannane as minor product, and the other is hexabutyldistannane (n-Bu3Sn)2 as major product. The distannane was produced by simple dehydrocoupling of n-Bu3SnH, whereas the cross-linked polystannane could be obtained via redistribution/dehydrocoupling combination process of n-Bu3SnH. The redistribution/dehydrocoupling combination process may initially produce a low-molecular-weight oligostannane with partial backbone Sn-H bonds which could then undergo an extensive cross-linking reaction of backbone Sn-H bonds, resulting in the formation of an insoluble polystannane.