• Fashion & Textile Research Journal
• /
• v.19 no.2
• /
• pp.240-248
• /
• 2017

This study compares general jacquard fabrics and jacquard fabrics with optical fiber on mechanical properties, sensibility and preference evaluation of fabric for the blind. The analysis also assesses the effect of optical fiber in the evaluation and identifies those best suited for consumers. The mechanical properties of jacquard fabrics were measured by the KES-FB system. Sensibility and the preference of the jacquard fabric for the blind were rated on tactile sensation by women experts in their 20's and 30's. It was found that the optical fiber in jacquard fabric affected the change of mechanical properties as well as sensibility and preference. Jacquard fabric with optical fiber were softer and more transformable, while the fabrics had lower recover property by shear force and compression as well as more violent unevenness. Jacquard fabrics were also classified into three hand factors of surface property, resilience and weightiness. There were significant differences on surface property perceptions and weightiness, hand and blind preferences by optical fiber. Jacquard fabrics that contained optical fiber were not preferred by the blind because they were perceived to be uneven and heavy. Those, that were smooth and light, were preferred for jacquard fabric; in addition, fabrics preferred by the blind had good compression.

• Journal of Mechanical Science and Technology
• /
• v.16 no.12
• /
• pp.1652-1663
• /
• 2002

It is desirable to perform nondestructive evaluation to assess material properties and part homogeneity because manufacturing of carbon/carbon (C/C) composites requires complicated and costly processes. In this work several ultrasonic techniques were applied to carbon/carbon composites for the evaluation of spatial variations in material properties that are attributable to the manufacturing process. In a large carbon/carbon composite manufactured by chemical vapor infiltration (CVI) method, the spatial variation of ultrasonic velocity was measured and found to be consistent with the densification behavior in CVI process in order to increase the density of C/C composites. Ultrasonic velocity and attenuation depend on a density variation of materials. Low frequency through-transmission scans based on both amplitude and time-of-flight of the ultrasonic pulse were used for mapping out the material property inhomogeneity These results were compared with that obtained by dry-coupling ultrasonics. Pulse-echo C-scans was used to image near-surface material property anomalies such as the placement of spacers between disks during CVI. Also, optical micrograph had been examined on the surface of C/C composites using a destructive way.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.2
• /
• pp.575-584
• /
• 1996

The objective of this paper is to develop an expert system for nuclear piping integrity. This paper describes the selection methodology of integrity evalution method and the inference of material properties. To select the integrity evaluation method, the weight factor for respective material properties was obtained by the sensitivity analysis of the effect of material properties on integrity evaluation method. Subsequently the possession ratio for respective integrity evaluation method was computed, and the most appropriate integrity evaluation method for given input information is selected. In the material properties inference, stress-strain curves and J-R curves were predicted from tensile properties such as yield strength and tensile strength.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.26 no.4
• /
• pp.436-440
• /
• 2017

This study evaluated the design and structural integrity of a three-axle bogie frame in a railway freight car through a numerical analysis and an experimental evaluation. A three-axle bogie frame, which supports the weight of the car body and load, is required to transport heavier cargo because two-axle vehicles have structural limitations. Therefore, this study performed a structural analysis and static load tests to evaluate the design and structural integrity of a three-axle bogie frame. The results obtained from the numerical analysis were compared to those of the experiments. For the bogie frame used in the experiments, a failure evaluation was performed using non-destructive methods. The numerical analysis and experimental evaluation were satisfactory for the structural integrity evaluation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.489-493
• /
• 2005

TFT-LCD(Thin Film Transistor Liquid Crystal Display) module is representative commercial product of FPD(Flat Panel Display). Thickness of TFT-LCD module is very thin. It is adopted for major display unit for IT devices such as Cellular Phone, Camcorder, Digital camera and etc. Due to the harsh user environment of mobile IT devices, it requires complicated structure and tight assembly. And user requirements for the mechanical functionalities of TFT-LCD module become more strict. However, TFT-LCD module is normally weak to high level transient mechanical shock. Since it uses thin crystallized panel. Therefore, anti-shock performance is classified as one of the most important design specifications. Traditionally, the product reliability against mechanical shock is confirmed by empirical method in the design-prototype-drop/impact testredesign paradigm. The method is time-consuming and expensive process. It lacks scientific insight and quantitative evaluation. In this article, a systematic design evaluation of TFT-LCD module for mobile IT devices is presented with combinations of FEA and testing to support the optimal shock proof display design procedure.

• Journal of the Ergonomics Society of Korea
• /
• v.30 no.2
• /
• pp.311-317
• /
• 2011

Objective: The present study was intended to identify (1) the intra- and inter-rater reliabilities of a visual sensibility evaluation protocol and (2) the effects of NaCOC color and scouring method on the visual sensibility of NaCOC. Thirty female participants(20s & 30s) were participated in the visual sensibility evaluation of NaCOC. Background: Interests in naturally colored organic cotton(NaCOC) increase rapidly in parallel with the social trend of eco-friendly living and wellbeing. Method: Three color sets (ivory, green, and coyote-brown) of NaCOC specimens including one untreated and four treated specimens($Na_2CO_3$; NaOH; enzyme; boiling water) were examined in the study. The visual sensibility evaluation was conducted by the test-retest method using nine pairs of bipolar visual sensibility adjectives(bright-dark; clear-murky; heavy-light; vivid-subdued; warm-cool; fresh-stale; strong-weak; showy-plain; and luxurious-cheap). Results: As a result of reliability of a visual sensibility evaluation protocol, inter-rater variability(average SD=1.06) of visual sensibility evaluation was more than 1.4 times the intra-rater variability(average SD=0.74). However, both the sensibility evaluation reliabilities did not show any systematic pattern of changes. Lastly, ANOVA and post-hoc analysis showed that preferred scouring methods for a visual sensibility adjective pair significantly vary depending on NaCOC color. Application: Both the reliability of visual sensibility evaluation protocol and the analysis of proper scoring method of NaCOC in the study would be useful information to design the affective textile.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2002.10b
• /
• pp.141-142
• /
• 2002

In this paper, we propose a slurry jet (water containing $1\;{\mu}m$ alumina particles) impact test in order to quickly evaluate the wear properties of physical vapor deposited (PVD) coatings on commercial cutting tools. Linear wear was obtained for bothe coating and substrate material, and the penetration through the coating into the substrate was signified by a sharp increase in slope of the wear versus time curve. The PVD coatings deposited on the tools showed the same wear rates as those on reference plate specimens produced by the same coating methods. We conclude that our proposed evaluation technique for coatings is considerably useful as a screening test when evaluating coated tools like twist drills, taps, end mills, gear hobs, etc.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.477-480
• /
• 2005

In this paper, the concept of sustainability was applied to mechanical design and manufacturing of mobile-phone case. A new evaluation method to find products' good and weak point for sustainability was developed. Two mobile phones were evaluated using the evaluation tool. As a result, electro-magnetic (EM) wave was considered as a harmful factor of the products, and improved front panel was made using nano particles that absorb EM waves. The EM shielding tests revealed that silver nano powders absorbed EM while MWCNT had no effect.

• Journal of Mechanical Science and Technology
• /
• v.19 no.3
• /
• pp.820-825
• /
• 2005

This paper proposes non-destructive ESPI technique to evaluate inside defects of semiconductor package quantitatively. Inspection system consists of ESPI system, thermal loading system and adiabatic chamber. The technique has high feasibility in non-destructive testing of semiconductor and gives solutions to the drawbacks in previous technique, time-consuming and the difficulty of quantitative evaluation. In result, most of defects are classified in delamination, from which it is inferred to the insufficiency of adhesive strength between layers and nonhomogeneous heat spread. The $90\%$ of tested samples have a delamination defect started at the around of the chip which may be related to heat spread design.

• Journal of Mechanical Science and Technology
• /
• v.16 no.9
• /
• pp.1072-1077
• /
• 2002

A degree of sharpness in wheel grains affects the surface roughness and dimensional accuracy in the grinding process. If a wheel with dull grains is used, the grinding force is increased and the surface roughness is deteriorated. In ovder to produce a precision component economically, the magnitude of the wear amount in the grinding wheel has to be limited. In this study, experimental evaluation of a wheel life varying with the grinding ratio and static grinding force was conducted. The grinding ratio and grinding force were measured to seek the grinding performance of the WA wheel. The relationship between the grinding ratio and static grinding force was presented.