• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1294-1297
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• 2007

In this paper, fabrication techniques for nanoscale metallic nanobeam specimens have been proposed, and mechanical properties of the fabricated gold nanobeams have been evaluated by nanoindentation techniques and nanobeam bending test. Elastic modulus and hardness of gold nanobeams were measured to be $109.6\;{\pm}\;10\;GPa\;and\;1.73\;{\pm}\;0.3\;GPa$, respectively, from the nanoindentation test, while elastic modulus was $241\;{\pm}\;7\;GPa$ from the nanobeam bending test.

• 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 the Korean Wood Science and Technology
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• v.33 no.5 s.133
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• pp.7-12
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• 2005

The objective of this study is to estimate the mechanical behavior in bending and the anatomical changes of wood under several deflection rates. Sample specimens of water-saturated Japanese cedar (Cryptomeria japonica) were stressed to rupture under several deflection rates. Mechanical properties of wood such as modulus of elasticity, modulus of rupture and stress at proportional limit, and anatomical changes affected by deflection rates were estimated. Microscopic observations on compression side of the test specimens when the specimen was loaded to rupture were carried out by the SEM (scanning electron microscopy). The results are summarized as follows: 1. The mechanical properties of wood were affected by variations of the deflection rates. The modulus of elasticity (MOE), modulus of rupture (MOR) and stress at proportional limit were in proportion to the logarithm of deflection rates. 2. The deflection of wood at rupture in bending increased as deflection rates decreased. 3. The variations of the microscopic deformations of sample specimens were closely related to the deflection of wood at rupture. In case of largely deflected wood by maximum bending load, severe and abundant microscopic deformations were observed.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.573-578
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• 2000

A bar with periodically nonuniform material properties is selected as a one-dimensional model of a flat-panel speaker. This paper describes a theoretical approach to the bending waves propagating in the nonuniform bar. The phase speed of the wave is obtained using perturbation techniques for small amplitude, sinusoidal modulation of the flexural rigidity and mass density. It is shown that the wave speed is decreased due to the nonuniformity of the material properties by the amount proportional to the square of the modulation amplitude.

• Journal of the Korean Wood Science and Technology
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• v.24 no.3
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• pp.12-17
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• 1996

This study was carried out to investigate some mechanical properties for wood rational utilization of heartwood and sapwood in radiata pine according to basic density, ring width and proportion of latewood which were grown in New Zealand. This result were summarized as follow: Heartwood showed 35.78(MPa) of the compression strength parallel to the grain while sapwood showed 42.08(MPa). The modulus of rupture in static bending was higher in sapwood showing 86.12(MPa) than in heartwood 72.99(MPa) Heartwood had 7.38(GPa) for the modulus of elasticity in static bending and sapwood 8.17(GPa). As the basic density and proportion of latewood increased: compression strength parallel to the grain, MOR and MOE in static bending had a tendency to increase. As ring width increased, the mechanical properties decreased.

• Steel and Composite Structures
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• v.11 no.4
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• pp.341-358
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• 2011

This paper presents the effects of thermal environment and temperature-dependence of the material properties on axisymmetric bending of functionally graded (FG) circular and annular plates. The material properties are assumed to be temperature-dependent and graded in the thickness direction. In order to accurately evaluate the effect of thermal environment, the initial thermal stresses are obtained by solving the thermoelastic equilibrium equations. Governing equations and the related boundary conditions, which include the effects of initial thermal stresses, are derived using the virtual work principle based on the elasticity theory. The differential quadrature method (DQM) as an efficient and robust numerical tool is used to obtain the initial thermal stresses and response of the plate. Comparison studies with some available results for FG plates are performed. The influences of temperature rise, temperature-dependence of material properties, material graded index and different geometrical parameters are carried out.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.10a
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• pp.54-59
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• 1998

In order to minimize straightness error of deflected shafts, a automatically bending process control system is designed, fabricated, and studied. The multi-step straightening process and the three-point bending process are developed for the geometric adaptive straightness control. Load-deflection relationship, on-line identification of variations of material properties, on-line springback prediction, and studied for the three-point bending processes. Selection of a loading point supporting condition are derved form fuzzy inference and fuzzy self-learning method in the multi-step straighternign process. Automatic straightening machine is fabricated by using the develped ideas. Validity of the proposed system si verified through experiments.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1998.06a
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• pp.17-24
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• 1998

This paper deals with the springback characteristics of cold rolled sheet steel through the use of the V-bending process and U-bending one. The influence of material properties on the springback of forming processes was investigated. In the V-bending process there was an optimum bend radius for each combination of parameters which produced minimal springback. In the U-bending process the blank holder force can control the degree of springback. A high blank holding force resulted in a uniform strain distribution and reduced the level of springback.

• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.385-392
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• 2014

The purpose of this study was to determine the effects of plantation thinning on physical and mechanical properties of Larix kaempferi. Tree samples were obtained from unthinned, moderately, heavily thinned plantations where located in Kwangryung forest research stand. The effects of different thinning methods on the bending and parallel to grain compressive strengths of Larix kaempferi were explored. Average latewood ratio with various thinning treatments revealed the trend of unthinning < moderate thinning < heavy thinning treatment. Average annual ring width with various thinning treatments showed the trend of unthinning < moderate thinning or heavy thinning treatment. Average bending and parallel to grain compressive strengths with various thinning treatments revealed the trend of unthinning > moderate thinning > heavy thinning treatment. This indicates that thinning treatment reduces average bending and parallel to grain compressive strength properties.

• Current Research on Agriculture and Life Sciences
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• v.31 no.3
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• pp.177-181
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• 2013

This study examined the effect of the molecular weight, substitution degree, and substitution type of cellulose ether on the mechanical properties of dried rice noodles. When increasing the molecular weight of the hydroxypropyl methylcellulose (HPMC), the bending strength of the dried rice noodles also increased. However, the bending strength of the rice noodles with added HPMCs was still lower than that of the wheat noodles. Meanwhile, the bending elongation of the dried rice noodles was higher than that of the wheat noodles and was increased when decreasing the molecular weight of the HPMC. In conclusion, the bending strength and elongation of dried rice noodles is affected by the substitution degree and type of cellulose ether.