• The Korean Journal of Ceramics
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• v.2 no.4
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• pp.226-230
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• 1996

A small amount of fine particle graphite was added to $\alpha$-SiC and $\beta$-SiC having certain particle distributions, and they were mixed clay and frit. After forming, they were sintered at 140$0^{\circ}C$ for 3 hours. Tribological properties of sintered $\alpha$-SiC-$\beta$-SiC-graphite-clay (frit) system showed that kinetic friction coefficient was 0.108, specific wear rate was 1.3${\times}10^-8\;mm^2$.$kgf^1$, and torque was 0.01kgf.cm at the wrench torque of 100 kgf.cm.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.244-248
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• 1998

The sound absorption materials are generally classified by three types, such as porous, resonator, panel. All of these types are based on theory of energy transform from sound energy to thermal energy. At first, the sound energy transform from the porous type uses to friction and viscose resistance. Secondly, resonator type uses to resonance frequency, absorption coefficient reach the highest.(omitted)

• Proceedings of the KWS Conference
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• 2006.05a
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• pp.286-288
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• 2006

The metallurgical and mechanical properties of fiction stir welded 304 austenitic stainless steel and AISI 1018 steel for fundamental study. Single-pass bead on plate weldments in the two steels were successfully achieved. The joints were evaluated by microscopy and hardness tests of the transverse cross section and transverse tensile tests.

• Proceedings of the KWS Conference
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• 2005.11a
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• pp.186-188
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• 2005

• Transactions of Materials Processing
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• v.9 no.6
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• pp.631-637
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• 2000

The tube hydroforming technology is new key production technologies, which contribute to a light-weight cu. Because the tubes are used for hydroforming instead of the sheet materials formability test for tube is required to measure the formability of materials for hydroforming. In this Paper, a kind of formability test for tube, which can well represent the characteristics of tube hydroforming processes, is developed. Developed formability test method can consider not oかy the influence of material Properties but also contact with die and material. Some investigation was carried out to verify the effectiveness of developed formability test.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.621-628
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• 2002

Compaction Grouting Pack (CGP) Anchor which is composite anchor of bearing plus friction-type was chosen and executed for the open-cuts in soft ground. This paper presents an analysis of data from tests on composite-anchor by jacking force. The properties of composite-anchor was presented to be as follows , the maximum plastic displacement was 60 mm in abandoned coal fill deposit, the shear stress($\tau$) is expressed as $\tau$ = (equation omitted) kg/$\textrm{cm}^2$ in clayey silt.

• Elastomers and Composites
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• v.50 no.4
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• pp.258-264
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• 2015

Rubber composites were prepared by precured CIIR pulverized at knead shear force in order to research the effects of the BR/PCP composites. The particle size of domain in BR/CIIR composites was decreased and homogeneously dispersed by the precured CIIR pulverized. However, it was difficult to use the product when the content is 40 phr and precured of 40%. BR/PCP composites have improved mechanical properies as compared that of the addition of simply cut chip composite.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.79-86
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• 2002

Rock mass classifications form the back bone of the empirical design approach and are widely employed in rock engineering. In this paper the inter-relations were discussed among RMR, Q-system, RCR, N, M-RMR, RMi, and L-RMR. Several relationships for the assessment of the modulus of deformation of rock mass, Poisson's ratio, uniaxial compressive strength, tensile strength, cohesion and internal friction angle were also analysed and suggested.

• Textile Coloration and Finishing
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• v.12 no.6
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• pp.361-371
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• 2000

The problematic effects of fly creation on circular knitting machines during the knitting process were investigated in order to develop a new method for tackling the problem. A new idea, i.e. coating the yarn surface with a polymer film, was studied. Important physical properties of the coated yarm were studied and compared with normal yarn. A new test-rig was designed to measure the coefficient of friction and the degree of shedding of yarn. Yarns were coated with seven polymer materials and the performance of the coated yarns was tested and the results are discussed.

• Journal of the Korean Vacuum Society
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• v.15 no.3
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• pp.287-293
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• 2006

Diamond-like carbon (DLC) film was deposited using benzene $(C_6H_6)$ by r. f-plasma assisted chemical vapor deposition. The tribological properties of the DLC film were tested by rotating ball-on-disc type tribometer isolated by a chamber. The tribological test was performed in air environment of relative humidity ranging from 0 to 90% in order to observe the tribological behavior of the DLC film with the change of humidity. We used steel ball and DLC coated steel ball to investigate the effect of the counterface material. Using steel ball, the friction coefficient of DLC film increased from 0.025 to 0.2 as the humidity increased from 0% to 90%. In case of DLC coated steel ball which didn't form the Fe-rich debris, the friction coefficient showed much lower dependence of humidity as 0.08 in relative humidity 90%. We confirmed that the high humidity dependence of the friction coefficient using steel ball resulted from the increase of debris size with humidity and the formation of Fe-rich debris by the wear of steel ball. And the friction coefficient was immediately dropped when the relative humidity changed from 90% to 0% during test using steel ball. From this result, we confirmed that the effect of the Fe-rich debris on the friction coefficient was that Fe element in debris formed the highly sensitive graphitic transfer layer to humidity.