• 한국정밀공학회지
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• 제18권7호
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• pp.161-166
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• 2001

The prototype of a tactile sensor with $4\times 4$ taxels using PVDF was fabricated. The electrode patterns of the thin Cu tape are attached to the 28${\mu}{\textrm}{m}$ thickness PVDF using conductive adhesive and covering the sensor using polyester film for insulation. The structure of the sensor is flexible and the fabrication procedure is easy relatively. Also the output characteristics of the sensor was nearly linear with 8% deviation. The signals of a contact pressure to the tactile sensor are sensed and processed through A/D converter, DSP system and personal computer. The reasonable performance for the detection of contact shape and force distribution was verified through the experiment.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1673-1678
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• 2007

The use of flip-chip type electronic package offers numerous advantages such as reduced thickness, improved environmental compatibility, and downed cost. Despite numerous benefits, flip-chip type packages bare several reliability problems. The most critical issue among them is their electrical performance deterioration upon consecutive thermal cycles attributed to gradual delamination growth through chip and adhesive film interface induced by CTE mismatch driven shear and peel stresses. The electronic package in use is heated continuously by itself. When the crack at a weak site of the electronic package occurs, thermal deformationon the chip side is changed. Therefore, we can measure these micro deformations by using Moire interferometry and find out the crack length.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.129-132
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• 2007

Advanced structure of metal-supported solid oxide fuel cells was devised to overcome sealing problem and mechanical instability in ceramic-supported solid oxide fuel cells. STS430 whose dimensions were 26mm diameter, 1mm thickness and 0.4mm channel width was used as metal support. Thin ceramic layer composed of anode(Ni/YSZ) and electrolyte(YSZ) was joined with STS430 metal support by using a cermet adhesive. $La_{0.8}Sr_{0.2}Co_{0.4}Mn_{0.6}O_{3}$ perovskite oxide was used as cathode material. It was noted that oxygen reduction reaction of cathode governed the overall cell performance from oxygen partial pressure dependance.

• 대한치과교정학회지
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• 제21권1호
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• pp.7-16
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• 1991

To estimate the possibility of the application of TiN ion-plating to the orthodontic appliance, colorimetric properties, and characteristics of ion-plated film as well as adhesive strength of TiN film to the substrate and mechanical properties of ion-plated orthodontic appliance were investigated. The obtained results were as follows: 1) TiN ion-plated film had the colorimetric properties which were the hue of about 2.5 Y, the brightness of about 6, and the chroma of about 4 by the standard color chip of JIS. 2) TiN ion-plated film was $2{\mu}m$ in thickness and its deposition pattern was rather irregular. 3) TiN phase was confirmed on the X-ray diffraction pattern. 4) Critical load for delamination of ion-plated film from stainless steel band was 10N. 5) Tensile and yield strength of ion-plated specimen was increased about 10Kg $f/mm^2$, while elongation was decreased $1\%$ compairing to the values of the non ion-plated specimen.

• 대한기계학회논문집A
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• 제25권11호
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• pp.1767-1776
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• 2001

For the stable operation of high speed air spindle, the low rotational inertia and high damping ratio of spindle shafts as well as high fundamental natural frequency are indispensable. Conventional steel spindles are net appropriate for very high speed operation because of their high rotational inertia and low damping ratio. In this study, a high speed spindle composed of carbon fiber epoxy composite shaft and steel flange was designed for maximum critical speed considering minimum static deflection and radial expansion due to bending load and centrifugal force during high speed relation. The stacking angle and the stacking thickness of the composite shaft and the adhesive bonding length of the 7teel flange were selected through vibrational analysis considering static and thermal loads due to temperature rise.

• 대한기계학회논문집A
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• 제24권8호
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• pp.2022-2031
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• 2000

Since the surface roughness of adherends affects much the strength of adhesivelybonded joints, the effect of surface roughness on the fatigue life of adhesively bonded tubular single lap joints was investigated analytically and experimentally by fatigue torsion test. The stiffness of the interfacial layer between adherends and adhesive was modeled as a normal statistical distribution function of surface roughness of adherends. From the investigation, it was found that the optimum surface roughness of adherends for the fatigue strength of tubular single lap joints was dependent on bondthickness and applied load.

• 한국표면공학회지
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• 제44권6호
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• pp.233-238
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• 2011

The friction and wear characteristics of CrN and TiN coatings on SKD61 which is mold material using for extrusion of AZ80 magnesium alloy were investigated. The coatings were deposited by the arc ion-plating method, and the thickness were about $3.59{\mu}m$ and $3.28{\mu}m$, respectively. Reciprocating friction wear tests were conducted by varying pin load and temperature of counter substrate at un-lubricated condition. The pin loads were 11, 15 and 19 kgf, and the substrate temperatures were room temperature and $120^{\circ}C$. CrN coating which has a lower friction coefficient and a smaller adhesive wear with AZ80 magnesium alloy showed better wear resistance than TiN coating.

• 한국자동차공학회논문집
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• 제17권3호
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• pp.15-21
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• 2009

The anisotropic mechanical properties were measured for the three orthogonal orientations of plain weave glass fabric reinforced epoxy resin laminate. In tensile and flexural tests, axial and edge type specimens failed by pull-out of warp and fill yarns, respectively. In contrast, the thickness type specimens failed by adhesive failure process. Longitudinal cracking occurred in several of the edge type specimens during tensile test. That cracking caused pop-in in the stress-strain curve. Defects induced by improper coupon machining caused that cracking.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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• pp.138-145
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• 2001

This paper presents F.E.M. analysis result about the behavior of R.C. beam repaired with steel plate and fiber sheet. The effect of repairing varies with reinforcement ratio of R.C. beam, plate thickness, numbers of fiber sheet, and repairing length, etc. F.E.M. analysis using a program, DIANA, was carried out taking these factors as parameter in this study. Analysis result shows that repaired R.C. beam behaves differently according to parameters and certain cases imply that repairing is useless or may lay structure in dangerous condition. F.E.M. model considers that interfacial behavior between different two parts of repaired beam is rigid based on an assumption that adhesive failure does not appear before yielding of reinforcement and its analysis shows the result coincides with that of experiment.

• Journal of the Korean Wood Science and Technology
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• 제36권5호
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• pp.11-23
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• 2008

The mechanical and physical properties of zinc borate (ZB)-modified oriented strandboard (OSB) from southern wood species were investigated in this study. OSB panels treated with ZB were not significantly weaker than the untreated samples in terms of specific modulus of elasticity (SMOE) and specific modulus of rupture (SMOR). ZB showed the negative effect on specific internal bond (SIB) strength, since some of ZB would persist as a powder state on the flake surfaces, thereby reducing the bonding efficiency of the adhesive. The ZB level did not show significant effect on thickness swelling (TS). ZB-modified OSB showed the suitable mechanical and physical properties for the structural wood composites.