• Macromolecular Research
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• v.15 no.1
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• pp.17-21
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• 2007

A series of new, vinyl sulfone-containing monomers was prepared by p-aminophenyl vinyl sulfone (1) with various acid chlorides such as adipoly chloride, terephthaloyl chloride and isophthaloyl chloride. Finally, tertiary amine-containing poly(amide-sulfone)s were prepared by the Michael-type addition polymerization using N,N-dimethylethylenediamine (DMEDA), p-phenylenediamine and piperazin. To evaluate the relevant properties for permselective membranes and enzyme substrate, various physical properties such as molecular weight, solubility, quaternization behavior and thermal properties were examined.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.1
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• pp.23-36
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• 1990

The various composite materials have been developed with the development of high strength material and the increasement of composite material usage. Therefore many researchers have studied about the stress analysis and the fracture mechanics for composite materials through the experiment or the theory. Among the experimental methods, the photoelastic experiments have been used for the stress analysis of the isotropic structures or the anisotropic structures. To analyze the stresses in the orthotropic material with photoelastic experiment, the basic physical properties ( $E_{L}$, $E_{T}$, $G_{LT}$ , .nu.$_{LT}$ ) and the basic stress fringe values ( $f_{L}$, $f_{T}$, $f_{LT}$ )are needed, therefore the relationships between the basic physical properties and the stress fringe values were derived in this paper. When the stress fringe value is very large, it was assured by the experiment that the relationships are established both in the room temperature and in the high temperature (T = 130.deg. C). Therefore the basic physical properties can be obtained from the relationships by measuring stress fringe values instead of measuring the basic physical properties.rties.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.103-108
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• 2013

This paper describes basic properties tests and non-rotating dynamic test for rotor blade, flexbeam, and torque tube of which bearingless rotor in helicopter consists. A basic properties test are bending and twist test to find the flap stiffness, lag stiffness, and twist stiffness of specimens. The purpose of dynamic test is to find natural frequencies and modes in non-rotating state. The test results are used to update the analysis model. The updated analysis results using rotorcraft comprehensive code match the tests quite well. The updated model input based on the tests will be utilized to analysis the conditions of rotating whirl tower test before the whirl test and will be compared with the whirl tower test results.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.92.3-92
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• 1998

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.127-128
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• 2006

Nafion/basic polymer composite membranes were prepared to reduce the methanol crossover for the application of direct methanol fuel cell. The thermal and mechanical properties increased with increasing basic polymer contents due to the formation of complex via acid/basic interaction. The water uptake, proton conductivity, methanol permeability decreased with increasing basic polymer concentration by reduction of acidity associated with the formation of acid/base complex. The molecular effect on those properties was not considerable.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.449-452
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• 2012

A polyaniline-gold composite was prepared via the polymerization of aniline hydrochloride with or without water-soluble graphite oxide using auric acid as an oxidant. The reaction products were characterized using Xray photoelectron spectroscopy. The thermal stability and embedded crystallinity of the composites were also investigated using thermogravimetric and X-ray diffraction analyses. The electrical properties of the composites were examined using cyclic voltammetric measurements at room temperature and temperature-dependent DC conductivity within 300-500 K. Compared to pure graphene oxide and polyaniline-gold composite, the polyaniline-gold-graphene composite exhibited higher crystallinity and thermal stability, and higher current density response under equivalent conditions.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.58-59
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• 2019

Data on basic properties are needed due to the increased interest of insulation materials, but In Korea, there are fewer data related to the basic properties of insulation. so the absorption rate was measured every seven days by selecting some of the insulation among insulation materials to provide basic data on absorption rates among basic properties. Measured over 43 days, both absorption and weight showed the highest PF levels, other insulation is judged to have almost reached the maximum absorption rate. PF is still an increasing trend and requires constant observation.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.681-686
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• 2001

The purpose of this study is to provide the optimum mix design of concrete to be placed at the face slab concrete in CFRD(Concrete Faced Rockfill Dam) for pumped storage power plants. The basic performance tests including compressive strength, modulus of elasticity, flexural strength and the control properties of crack including plastic shrinkage, drying shrinkage were conducted for concrete using fly ash and polypropylene fiber. From this study, the fly ash concrete represented the better results in the aspects of basic performance, control properties of crack and economy than ordinary portland cement concrete. Especially the concrete mix design containing 20% of fly ash is recommended to be applied in the construction of the face slab concrete in CFRD for pumped storage power plants.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.757-760
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• 2006

This study aims to manufacture ultra fine cement(UFC) with a multi air-classifier of the dry-type. The classifier employed and devised for materials refining was a cyclone type fitted with an air suction device. This study also investigates the basic physical properties and quality of UFC and evaluates its utilizable possibility as a construction material. The basic properties of the UFC containing granulated blast furnace slag were analyzed and examined through recovery ratio, particle size distribution, scanning electron microscopy and compressive strength. Results obtained from the analysis of ultra fine cement have shown that there are possibilities for manufacturing UFC, which could compensate the weak properties of ordinary Portland cement.

• Honam Mathematical Journal
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• v.26 no.1
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• pp.17-41
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• 2004

In this paper, we obtain the intuitionistic fuzzy subgroups generated by intuitionistic fuzzy sets and some properties preserved by a ring homomorphism. Furthermore, we introduce the concept of intuitionistic fuzzy coset and study some of it's properties.