• Applied Microscopy
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• v.45 no.2
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• pp.63-73
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• 2015

Shear banding is an evidence of plastic instability that localizes large shear strains in a relatively thin band when a material is plastically deformed. Shear bands have attracted much attention in amorphous metals, because shear bands are the key feature that controls the plastic deformation process. In this article, we review recent advances in understanding of the shear bands in amorphous metals regarding: dislocations versus shear bands, the formation of shear bands, hot versus cold shear bands, and property manipulation by shear band engineering. Although there are many key issues that remain puzzling, the understanding built-up from these approaches will provide a new insight for tailoring shear bands in amorphous metals, which potentially leads to unique property changes as well as improved mechanical properties. Indeed, this effort might open a new era to the future use of amorphous metals as a new menu of engineering materials.

• Journal of the Korea Fashion and Costume Design Association
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• v.3 no.2
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• pp.63-73
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• 2001

Underwears treated by aroma capsule(UTA) have been known to have many advantages than normal underwears, for example, UTA has antimicrobial and deodorant properties. In this experiment, we examined antimicrobial and deodorant effect of UTA treated by rose and lemon fragrance, Mechanical properties of UTA including surface property, bending property and shear property were also tested. The results are as follows,1. The effects of antibacterial is estimated as 33% and the efficiency of deodouration is about 95 % in UTA. 2. The fragrance of UTA maintained even after 25 times washout. 3. Bending and shear properties were not changed in UTA However it decreased the coefficient of friction of the textures and the smooth surface was detected when the human skin was contacted.

• Journal of Biosystems Engineering
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• v.33 no.6
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• pp.416-422
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• 2008

This study was performed to design and construct a digital soil shear stress sensor in order to replace the conventional devices for measuring soil shear property. The developed digital shear stress measuring device can store measured data with GPS position information as a vector format into a computer. Based on the experiments at various field conditions, the measuring characteristic of the device was quite similar to that of a conventional device, SR-2 that has been a major tool to measure the soil shear property. It was concluded that the digital shear stress measuring device was an effective and comprehensive sensor for measuring soil shear property.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.58-65
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• 2008

Most connections for the glulam structural members consisted of connector and fastener. The mechanical behaviour of the connection can be occurred by the dowel bearing resistance and wood shear by the fastener. This study aims at the examination of the shear properties for the small specimen with lamination components and for the full-sized pin connection and the moment resisting property for the double shear full-sized pin connection using structural column and beam members. Small specimens including glue line shows greater density and shear strength by the lamination effect than other specimens. It is needed that estimations of double shear property and moment resistance for the pin connections should be adjusted in some degree. For the better and safe estimation of moment resistance strength for the column-beam pin connection, however, the shear strength of small specimens should be deducted by 10%.

• Journal of Industrial Technology
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• v.34
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• pp.11-14
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• 2014

Viscosity and shear stress of the dental impression materials on commercial market(Imprint Garant LB(3M, U.S.A), EXAMIXFINE IT(GC, Japan), Vonflex S LB(Vericom, Korea), S-Silicone LB(Shinwon, Korea)) were measured with increasing shear rate from 50(1/sec) to 100(1/sec). The viscosity of EXAMIXFINE IT was decreased from 20,542(cP) to 14,684(cP), which is the shear thinning property of pseudoplastic as non-Newtonian fluid. Since the pseudoplastic property makes the impression material shear thinning and softly injected from cartridge, EXAMIXFINE IT might be popularly used in dentistry.

• Journal of Technologic Dentistry
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• v.35 no.2
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• pp.113-120
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• 2013

Purpose: This study was to observe surface property and bonding strength according to composition of Ni-Cr alloy for porcelain fused to metal crown. The two kinds of Ni-Cr alloy with different composition ratio of parent metal were observed general properties and chemical properties of each alloy surface and measured the shear bonding strength between ceramic and each alloys. The aim of study was to suggest the material for design of parent metal's composition ratio to development of alloy for porcelain fused to metal crown. Methods: The two kinds of alloy as test specimen was Ni(71wt.%)-Cr(12wt.%) and Ni(63wt.%)-Cr(23wt.%) alloy. The oxide on surface was observed by SEM and EDX. And the shear test was performed by MTS. Results: The surface property and oxide characteristic analysis of oxide layer, weight percentage of Element O within $Ni_{71}Cr_{12}$ alloy measured 12.74wt.%, but $Ni_{63}Cr_{23}$ alloy was measured 15.91wt.%. And the maximum shear bonding strength was measured 106.14MPa between $Ni_{71}Cr_{12}$ alloy and vintage halo (VV group). Conclusion: The surface property and oxide characteristic of $Ni_{71}Cr_{12}$ alloy was similar to $Ni_{63}Cr_{23}$ alloy. And VV group has the strongest shear bonding strength.

• International Journal of Highway Engineering
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• v.15 no.1
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• pp.87-94
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• 2013

PURPOSES: To characterize the aging effect on asphalt binder, dynamic shear modulus mastercurve of two typical asphalt binders are developed. METHODS: To develop dynamic shear modulus mastercurve, dynamic shear modulus at high temperature and creep stiffness at low temperature are measured by temperature sweep test and bending beam rheometer test, respectively. RESULTS: It is observed that the aging effect on asphalt binder can be clearly observed from dynamic shear modulus mastercurve and the mastercurve can be utilized to predict behavior of asphalt binder at wide range of temperature. CONCLUSIONS: It is confirmed that SBS 5% modified binder has more desirable mechanical property at low and high temperature as a pavement material comparing to PG64-22 binder and the mastercurve is an effective tool to evaluate the property of asphalt binder.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.2 s.146
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• pp.268-274
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• 2006

Analysis has been made of the anti-corrosive property of organic coating under the shear stress of the flow by means of AC impedance method. Marine anti-corrosive painted panels were placed in the water channel with varying flow rate, thereby experiencing varying flow shear stress on the surfaces. The velocities of the salt water were ranged from 1.48 to 5.2 m/s and the coating thickness of from $70{\mu}m\;to\;140{\mu}m$. For all coating thicknesses investigated, the poorer anti-corrosive property and the lower adhesion strength have been found for the higher shear stress. It has been found that the shear stress accelerates the aging of organic marine coatings.

• Journal of Technologic Dentistry
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• v.35 no.4
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• pp.353-358
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• 2013

Purpose: This study was observation shear bonding strength by compositional change and firing step of a Ni-Cr alloy for porcelain fused metal crown. The aim of study was to suggest the material for firing step of Ni71-Cr14 alloy to development of alloy for porcelain fused to metal crown. Methods: The test was on the two kinds of Ni-Cr alloy specimens. The surfaces of two alloys were analyzed by EDX in order to observe oxide characteristic. And the shear test was performed by MTS. Results: The surface property and oxide characteristic analysis of oxide layer, weight percentage of Element O within $Ni_{71}Cr_{14}$ alloy measured 23.32wt%, and $Ni_{59}Cr_{24}$ alloy was measured 23.03wt%. And the maximum shear bonding strength was measured 58.02MPa between $Ni_{59}Cr_{24}$ alloy and vintage halo(H4 group). Conclusion: The surface property and oxide characteristic three kind of Ni-Cr alloy was similar. and shear bonding strength showed the highest bonding strength in H4 specimens.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.367-372
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• 2002

In these days, The base isolation system is often used to improve the seismic capacity of the structures instead of conventional techniques of strengthening the structural members. The purpose of this study is to evaluate dynamic properties and mechanical characteristics of the 10tonf-LRB(Lead-Rubber Bearing). Experimental studies were performed to obtain the hysteretic behavior, effective shear stiffness( $K_{eff}$), equivalent damping( $H_{eq}$ ), capacity of energy dissipation( $W_{D}$) of six 10tonf-LRB. Especially, in this study, the response of the LRB for high loading frequency(0.5Hz~3.0Hz) was estimated. The effective shear stiffness of the LRB decreases and the capacity of energy dissipation increases as the shear strain amplitude increases. But the shear behavior of the LRB is not affected sensitively by loading frequency.y.y.