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Paper Title Page
Abstract: The stroboscopic phase shifting ESPI (SPS-ESPI), one of the optical vibration amplitude
measurement techniques, is presented. Although the general PS-ESPI can be used for quantitative
deformation measurement of the object, this technique cannot measure the vibration amplitude with
itself only. The phase change due to the vibration of the object cannot be calculated with general
PS-ESPI correctly. Therefore, in order to solve this problem, the stroboscopic illumination must be
introduced to the general PS-ESPI. This can be done by using a device called as AOM (Acousto-Optic
Modulator). In this paper, SPS-ESPI is applied to measure the vibration amplitude of the square plate
whose all edges were fixed. The natural frequencies and mode shapes are analyzed by using ANSYS.
And the results obtained by using SPS-ESPI technique are compared with that of the ANSYS
analysis. The vibration amplitude is measured by using SPS-ESPI quantitatively.
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Abstract: The profile of the mirror surface is measured by using optical phase shift method and
Twymann-Green interferometer. Phase map is calculated by applying 4–buckets method and
Vikhagen phase shift algorithm is applied to escape convolution errors. From that the obtained
roughness of the mirror surface is around 20 nm rms roughness value. Also, the interferometer was
stabilized by using fringe locking method. Also, we propose two colors method very precise surface
profile and the length can be measured in the harsh environmental conditions.
99
Abstract: We present a suppressing technique of the antisymmetric mode by superposition of Lamb
waves generated by two laser beams in a thin plate. Two Lamb waves of the same frequency
propagating from the opposite direction simultaneously arrive at the point of measurement and are
superposed to compose one Lamb wave. The amplitude of the superposed Lamb wave depends on the
distance between two laser beams. The suppressing of antisymmetric Lamb wave mode is
accomplished by selecting the distance between two beams which simultaneously satisfies the
condition of the anti-node(maximum) for the symmetric mode and the minimum for the
antisymmetric mode. By this method, the antisymmetric Lamb wave mode is suppressed to the degree
of 1.4% of the amplitude measured at zero distance between two beams.
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Abstract: We present a laser-ultrasonic technique to generate the lowest symmetric ( ) Lamb
wave in a thin plate. Using this special technique, in which two symmetric laser beams
quasi-simultaneously hit at the same point on both sides of the plate, we absolutely suppress
anti-symmetric Lamb wave modes. This technique is applicable to any situation that requires
symmetric Lamb wave mode operation and does not need additional contacts or special equipments.
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Abstract: Shearography, a type of speckle interferometry, is a powerful tool for nondestructive
testing (NDT) because it is insensitive to environmental vibration disturbance and easy to detect strain
concentration in an internal defect with noncontact and whole field. The shearing amount in
Shearography has influence on determining defect size and source location. Thus the shearing amount
must be optimally adjusted to get accurate evaluation. This paper investigates the defect size and
source location according to the change of shearing amount in artificial slender defects along
longitudinal direction of pipeline. Based on the investigation, a new technique is proposed for the
quantitative determination of defect size and source location.
112
Abstract: To measure the micro-mechanical properties for micro/nano materials, out-of-plane ESPI
system and micro-strip bend testing system were developed. For the bending system, PZT actuator
was controlled with the stroke resolution of 0.6 nm and out-of-plane ESPI system was developed in
compact and portable type. To quantitatively analyze the out-of-plane ESPI fringe patterns, 4-bucket
technique was used and unwrapped phase map was obtained. Electrolytic copper foil with the
thickness of 18 μm was used for preparation of the strip bend specimen with length of 8 mm and three
different widths of 2, 3 and 5 mm. The strip bending tests showed that the out-of-plane deflection in
the bend specimen was measured with a maximum of 8 % in error. Furthermore, from the experiment,
the variation of the deflection along the supporting span could be determined and significant region
was linear.
116
Abstract: In this study, we use the strip-bending test to measure the residual stress of a thin film
structure. The principle of the strip bending test and the test procedures are described and the analysis
of the strip deformation is presented. The explicit formula for estimating the residual stress is given,
which requires the initial stress as an input. As an example, the E-beam evaporated Au thin film is
chosen, and the residual stress is measured by the present method. The Au thin film structure has a
tensile or compressive residual stress depending on the film thickness. The tensile and the
compressive residual stresses of Au thin film are successfully measured by the present method.
121
Abstract: The gas electron multiplier (GEM), placed in the drift volume of a conventional gas
detector, is a conceptually simple device for producing a large gas gain by concentrating the drift
electric field over a very short distance to the point that electron avalanching occurs. This device
consists of a thin insulating foil of several tens of μm in thickness, covered on each side with a thin
metal layer, with tiny holes, usually 100 μm or less in diameter, and with a spacing of 100-200 μm
through the entire foil, perforated by using chemical etching or high-powered laser beam technique. In
this study, we have investigated its operating properties with various experimental conditions and
demonstrated the possibility of using this device as a digital X-ray imaging sensor, by acquiring X-ray
images based upon the scintillation lights of the GEM with a standard CCD camera.
125
Abstract: In this study, we investigated indentation behavior by varying the tip radius in a finite
element model. We measured the tip radius and shape of the nano-indenter by SPM (scanning probe
microscope) and compared them with the simulation results. The tip radius of cube corner indenter
was measured to be 39nm, in agreement with the common tip radius of such indenters, which range
from 20~50nm.
129
Abstract: As cMUTs (capacitive Micromachined Ultrasonic Transducer) offer numerous advantages
over traditional transducers in terms of efficiency, bandwidth, and cost, they are expected to replace
piezoelectric transducers in many applications. In particular, 2D-array cMUTs have aroused great
interest in the medical engineering society because of their ability to materialize a true volumetric
ultrasonic image. In this study, single element cMUTs with 32 x 32 and 64 x 64 cells were
successfully fabricated. The diameter and thickness of the membrane are 35 and 1000 nm,
respectively, with a sacrificial layer thickness of 600 nm. The electric characteristics of the fabricated
cMUT were measured. Tests on the efficiencies of the cMUT in terms of wave generation and in
terms of detection according to the bias and pulse voltage were performed in an air atmosphere.
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