bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study on Properties and Kinetics of Carburizing Superplastic Duplex Stainless Steel
Authors: Masdek Nik Rozlin Nik , Jauhari Iswadi , Ramdan Raden Dadan , Hasan Rafidah
Published: March 2009

In this study, a new type of surface carburizing process was introduced using
superplastic duplex stainless steel (DSS). The superplastic DSS was carburized at temperatures
ranging from 1123 K to 1223 K for various durations. Initial pressures of 25 MPa, 49 MPa and
74 MPa were applied to give the superplastic deformation effect on the carburized specimens.
SEM studies revealed a thick, uniform, smooth and dense hard carbon layer was formed on the
surface of the superplastic DSS. By using metallographic technique and SEM, the resulting case
depth of carbon layer was between 15 /m to 76 /m. The kinetics of this process in terms of
carbon diffusion and its variation with processing time and temperature was determined using
Arrhenius equation. Activation energy (Q) was determined as 152 kJ/mol.
Experimental Investigation on 2D and 3D Braided C/SiC Composites
Authors: Wang Bo , Jiao Gui Qiong , Chang Yan Jun , Pan Wen Ge
Published: March 2009

Tensile tests of two-dimensionally braided C/SiC composites and three-dimensionally
braided C/SiC composites had been carried out at room temperature. Some specimens had been
unloaded during experiments. Acoustic Emission signals also had been collected during
experiments. The following conclusions were arrived. The stress-strain curves of these two
materials were of nonlinear characters, and there were no obvious linear segments on those curves.
Failure characters of these two materials were different: There appeared ply pull-out for 2D braided
C/SiC specimens and there appeared zigzag shape for 3D braided C/SiC specimens. Stress-strain
curves of loading-unloading tests and Acoustic Emission signals of those two materials showed
damage evaluation during tests. There were different AE counts and AE energy characters between
two materials.
Low Pressure Casting Process of FeCrSi/A366.0 Alloy Composites and Their Characterization
Authors: Choi Yong Bum , Gen Sasaki , Kazuhiro Matsugi , Shunsaku Kondoh , Osamu Yanagisawa
Published: March 2009

Low pressure casting process was considered for fabrication of FeCrSi metal fiber
reinforced A366.0 aluminum composites. FeCrSi/A366.0 alloy composite was fabricated by applied
pressure 0.8MPa. The microstructure features, tensile strength and fatigue life of composites were
investigated from room temperature to high temperature. It was confirmed that the FeCrSi metal
fiber did indeed have a strengthening effect on the composite, lending it good mechanical properties
and a good fatigue life at high temperatures.
Experimental and Numerical Study on Flapping Wing Kinematics and Aerodynamics of Coleoptera
Authors: Saputra Saputra , Byun Do Young , Byun Yung Hwan , Park Hoon Cheol
Published: March 2009

In this study we have experimentally and numerically analyzed the flapping mechanism
and wing kinematics of coleoptera (Propylea japonica Thunberg). Using digital high speed camera,
we captured the continuous wing kinematics and visualized the flight motion of the free-flying
coleoptera. The experimental visualization shows that the elytra flapped concurrently with the main
wing both in the downstroke and upstroke motions. In order to define the wing kinematics of
coleoptera, the displacement of a wing cross section (50% span-wise) was measured for each
sequence of the wing motion. Using these data, the flight motion of coleoptera was numerically
simulated to investigate the aerodynamic performance. The computational aerodynamic simulation
shows that leading edge vortex shedding plays a key role in generating lift to keep the insect aloft.
Seismic Performance of In-Filled Steel-Concrete Composite Columns Using Fiber Analysis Method
Authors: Kim Jin Ho , Kim Tae Wook
Published: March 2009

The study for cyclic load-displacement relationship and seismic characteristics of square
Concrete-Filled Steel Tubular (CFT) columns is experimentally and analytically conducted. Nine
CFT column specimens are tested under constant axial loading and monotonically increasing lateral
loading. For predicting the strength and ductility of CFT columns, fiber analysis technique is used.
The analytical results show reasonable agreement with experiment results and the moment capacity
of CFT columns is predicted with reasonable accuracy using the fiber model. The influence of the
steel tube on the lateral response of CFT columns is studied for the evaluation of seismic
performance.
Wear Behavior of SiCp Reinforced Metal Matrix Composites Fabricatied by Thermal Spray Process
Authors: Kim Yeong Sik , Kim Kyun Tak
Published: March 2009

SiC particulates reinforced with Al matrix composites were fabricated using a thermal
spray process. In addition, the dry sliding wear behavior was investigated using various sliding
speeds and applied loads. Premixed Al and SiC powder was sprayed onto an Al6061 substrate by
flame spraying, and dry sliding wear tests were performed under varying sliding speed and applied
load conditions. Wear behavior of the composites were studied using a scanning electron
microscope(SEM), X-ray diffraction(XRD) and a surface roughness tester.
Development of Phase Shifting Device Using the Deflection of a Cantilever for Digital Holography
Authors: Matsukawa Hitomi , Fujigaki Motoharu , Matui Toru , Morimoto Yoshiharu
Published: March 2009

Phase-shifting digital holography can be used for displacement measurement instead of
strain gauge. Our research group is developing the measurement equipment for phase-shifting
digital holography. Generally, in the measurement equipment, piezo stages are used as phaseshifting
devices. But the piezo stage is expensive. Cheaper and smaller phase-shifting device is
required in order to put the measurement equipment into practical use. In this paper, we, therefore,
propose a phase-shifting device using the deflection of a cantilever and we verify whether this
phase-shifting device can be usedfor digital holography.
A Study of Nano-Indentation Test Using Rhombus-Shaped Cantilever in Atomic Force Microscope
Authors: Cho Ki Ho , Lee Hak Joo , Kim Jae Hyun , Kim Jong Man , Kim Yong Kweon , Baek Chang Wook
Published: March 2009

We have designed and fabricated diamond-shaped AFM cantilevers capable of
performing multi-functioning tasks by using single crystal silicon (SCS) micromachining
techniques. Structural improvement of the cantilever has clearly solved the crucial problems
resulted from using conventional simple beam-AFM cantilever for mechanical testing. After forcecalibration
of the cantilever, indentation tests are performed to determine the mechanical behaviors
in micro/nano-scale as well as topographic imaging. A diamond Berkovich tip of which radius at the
apex is approximately 20 nm is attached on the cantilever for the indentation test and 3D topography
measurement. The indentation load-depth curves of nano-scale polymeric pattern (PAK01-UV curable
blended resin) are measured and surface topography right after indenting is also obtained. Development of
this novel cantilever will extend the AFM functionality into the highly sensitive mechanical testing
devices in nano/pico scale.
Vibration Analysis of Membrane by Time Average In-Line Digital Holographic Interferometry
Authors: Singh Vijay Raj , Asundi Anand Krishna
Published: March 2009

In this paper, in-line digital holography is combined with time average method and applied for
vibration analysis of an aluminum membrane. The numerically reconstructed wave from time
average holograms contains information of mode shape and mean deformation of the vibrating
objects. At lower amplitudes of vibration only the deformation fringes are observed and as the
amplitude is increases, the Bessel fringes representing the time average vibration amplitude also
become visible. Experimental results for a 10mm size membrane are presented.
Design and Performance Test of Digital Rebalance Loop for MEMS Gyroscope
Authors: Chang Byung Su , Lee Jang Gyu , Kang Tae Sam
Published: March 2009

In this paper, a digital rebalance loop for MEMS gyroscope is designed and its
performance test is performed. First, the system model of MEMS gyroscope is established by
dynamic analysis. Then, the digital rebalance loop is designed using modern control technique. The
performance of the digital rebalance loop is compared with that of conventional PID rebalance loop.
Through frequency response analysis using MATLAB and experiments using a real MEMS
gyroscope and digital controller, which is realized using digital signal processor (DSP), it is
confirmed that the controller improves the performance of the gyroscope.
Fine Micro Patterning of Conductive Line by Using Direct Inkjet Printing
Authors: Park Sung Jun , Seo Shang Hoon , Joung Jae Woo
Published: March 2009

A novel selective metallization process to fabricate the fine conductive line based on
drop-on-demand (DoD) inkjet printing was studied. Direct inkjet printing is an alternative and costeffective
technology for patterning and fabricating objects directly from design or image files
without making masks and patterns. The conductive ink used in this experiment consists of 1 to 50
nm silver particles that are homogeneously suspended in an organic carrier. A piezo-electric inkjet
print head driven by a bipolar voltage signal is used to dispense 20-40μm diameter droplets.
Repeatability of circuitry fabrication is closely related to the formation of steady, satellite-free
droplets. Therefore, the ability to form small and stable droplets with a same size, constant velocity
and the correct flight angle must be taken into consideration for fine and precise conductive lines. In
this study, parameters affecting the pattern formation such as drop formation, drop placement
accuracy and velocity deviation between each nozzle have been investigated. As a result, direct
inkjet patterning systems equipped with several functioning modules and fine metallic patterns have
been developed.
Simulation Assisted Measurement of Nanoparticle Concentration Generated during High-Density Plasma CVD of Poly-Silicon Films
Authors: Kim Tae Sung , Ko H.S. , Kwon Oh Chae
Published: March 2009

To study nanoparticles generated within the high-density plasma system, it is necessary
to know the particle concentration (#/cm3), which is typically measured using laser light scattering
of particles trapped inside the plasma. This technique has limitations because particles are localized
due to the forces that act on the trapped particles inside the plasma and the localization point varies
as the particles grow. Unless spatially averaged particle concentrations are obtained by scanning
through the plasma, laser light scattering measurements of particle concentration might represent
only the local variation of particle concentration. In this paper, novel method is presented to
measure the particle concentration employing TEM measurement results and the simulation of
particle transport for calculation of transport efficiency from the plasma region where the particles
are generated to the TEM grid. As the particles were collected on the TEM grid after the plasma
was extinguished, the simulation includes the effects of Brownian diffusion, aerodynamic drag and
gravitational sedimentation but not electrostatic or ion drag force. Simulation results were obtained
for particles ranging from 5 to 100 nm. For each particle size, transport efficiencies from 56
different starting positions were evaluated. It was found that transport efficiencies of particles in the
20 to 50 nm diameter range were highest, since these particles tend to follow the gas flow.
Sampling efficiencies of particles smaller than this decreased due to Brownian diffusion. For larger
particles, sampling efficiencies also decreased, due to gravitational sedimentation. The measured
particle concentrations were found to be ~108 #/cm3 and roughly constant over time.
Tribological Performance of Ordered Mesoporous Carbons in Mineral Oils Under Boundary Lubricated Sliding
Authors: Baik Seung Hyun , Kim Ji Man , Lee Kyu Sun , Yoon Do Kyung , Lee Hyung Ik , Lee Young Ze
Published: March 2009

The tribological performance of ordered mesoporous carbons (CMK-3) as lubricant
additives is investigated at ambient temperature. The effects of CMK-3 on the frictional forces,
wear amounts and cycles to scuffing are measured using a ball-on-disk tester. It was found that
there was little difference in the frictional forces and wear amounts of the oils with and without
CMK-3. However, the scuffing time of the oil with CMK-3 was much longer than that of the pure
mineral oil in sliding tests. CMK-3 were very effective on maintaining the oil gap and protecting
the surfaces in boundary lubricated sliding.
Estimation of Elastic-Plastic Tensile Properties Using Nano-Indentation Tests and FE Simulations
Authors: Kim Yun Jae , Song Tae Kwang , Hanh Jun Hee , Park Jun Hyub
Published: March 2009

This paper discusses possibilities to extract elastic-plastic properties of nano-scale
materials using combined nano-indentation tests with FE simulations. One interesting finding is that
FE simulations of nano-indentation with a number of different plastic properties give same
load-displacement response, which suggests that plastic properties cannot be determined from
simulating load-depth curves from nano-indentation tests. However, careful examination of possible
plastic properties suggests a concept of the reference strain, which makes it possible to effectively
determine plastic properties from nano-indentation tests with FE simulations.
Influence of Grain Size on Magnetic Properties of Electroplated NiFe
Authors: Yusrini Marita , Iskandar Idris Yaacob
Published: March 2009

Nickel-Iron nanocrystalline alloys with different grain sizes were fabricated by
electrodeposition technique. In this study, influence of the grain size nanocrystalline NiFe
deposits on saturation magnetization Ms and coercivity Hc was investigated. Alternating gradient
magnetometer (AGM) with up to 10 kOe applied magnetic field was used to study the magnetic
properties of NiFe film. The results showed that saturation magnetization Ms and coercivity Hc
were affected by grain size variation. Increase in grain size increased the saturation magnetization.
The largest grain size of 18.6 nm showed the highest Ms of 138 emu/g, while the smallest grain size
of 7.2 nm showed Ms of 94 emu/g. Minimum coercivity of 3.847 Oe was observed for sample
with 7.2 nm grain sizes. The coercivities decreased for smaller grain sizes.
Instantaneous Spatial Phase-Stepping Methods for Phase-Measuring Interferometry and Photoelasticity
Authors: Yoneyama Satoru , Mizuhara M. , Kikuta H. , Moriwaki K.
Published: March 2009

This paper demonstrates instantaneous phase-stepping and subsequent phase analysis
methods for interferometry and two-dimensional photoelasticity. The camera that has a pixelated
form-birefringent micro-retarder array acquires phase-stepped fringes in a single camera frame.
Then, the distributions of Stokes parameters that represent the state of polarization are calculated
from a single image. In the case of the polarization interferometer, the phase difference of the two
orthogonally polarized light beam can be easily determined from the Stokes parameters. On the
other hand, the phase distributions of the isochromatics and the isoclinics are obtained in the case of
the photoelasticity. It is emphasized that this method is applicable to real-time inspection of optical
elements as well as the study of the mechanics of time-dependent materials because multiple
exposures are unnecessary for sufficient data acquisition in the completion of data analysis.
Monitoring of Brittle-Ductile Transition during AFM Machining Using Acoustic Emission
Authors: Lee Seoung Hwan , Ahn Byoung Woon
Published: March 2009

An atomic force microscope (AFM) with suitable tips has been used for nano
fabrication/nanometric machining purposes. In this paper, acoustic emission (AE) was introduced to
monitor the nanometric machining of a brittle material (silicon) using AFM. In the experiments, AE
responses were sampled, as the tip load was linearly increased (ramped load), to investigate
machining characteristics during continuous movement. By analyzing the experimental results, it
can be concluded that measured AE energy is sensitive to changes in the mechanism of material
removal including the ductile-brittle transition during nanometric machining. The critical depth of
cut value for the transition is evaluated and discussed.
Fabrication of the Fine Magnetic Abrasives by Using Mechanical Alloying Process and its Polishing Characteristics
Authors: Park Sung Jun , Lee Sang Jo
Published: March 2009

A new method to fabricate the fine magnetic abrasives by using mechanical alloying is
proposed. The mechanical alloying process is a solid powder process where the powder particles are
subjected to high energetic impact by the balls in a vial. As the powder particles in the vial are
continuously impacted by the balls, cold welding between particles and fracturing of the particles
take place repeatedly during the ball milling process using a planetary mill. After the manufacturing
process, fine magnetic abrasives which the guest abrasive particles clung to the base metal matrix
without bonding material can be obtained. The shape of the newly fabricated fine magnetic
abrasives was investigated using SEM and its polishing performance was verified by experiment. It
is very helpful to finishing the micro structures such as injection mold and MEMS applications in
final polishing stage. The areal rms surface roughness of the workpiece after several polishing
processes has decreased to a few nanometer scales.
Influence of Ultrasound Power on the Formation of Submicron Etch Pits during Sonoelectrochemical Etching of Aluminum
Authors: Kang Jin Wook , Ko Eun Seong , Lee Jae Kwang , Tak Yong Sug
Published: March 2009

Ultrasound was superimposed during electrochemical etching of aluminum and the
effect of ultrasonic power on the formation and growth of etch pits were analyzed with the
measurement of fast potential transient and morphology study. Ultrasound contributed the increase
of etch pit density by prohibiting anodic oxide film formation and induced uniform tunnel length
distribution. Current step reduction experiments indicated the enhanced mass transfer both inside
tunnel and bulk solution with the increase of ultrasonic power. The capacitance of etched foil was
increased by 40% with 600W of 28 KHz ultrasonic power.
Self-Organized Nanoporous Thin-Film Titania Templates Prepared by Anodic Oxidation
Authors: Yang Dae Jin , Kim Ho Gi , Choi Won Youl
Published: March 2009

Thin-film titania templates were fabricated under different processing conditions. The
dependencies of pore morphology and pore formation rate on process parameters were evaluated. It
was found that under optimized electrolyte condition and anodizing voltage, a self-organized
nanostructure consisting of porous TiO2 was obtained. 1 M Na2SO4 solution with the addition of
0.35 wt.% NaF and voltage potential of 30V were used. SEM images of templates showed very thin
layer of ~70 nm thickness with worm-like pores. Pore diameter and average pore spacing of center
to center on the surface were ~10 nm and 20 nm, respectively. The nanoporous TiO2 thin film will
be very useful gas sensing and photocatalytic materials due to their large surface areas and high
reactivities.
A Study on Identification of Bubble Movements in an Automatic Wheel Leakage Detection System
Authors: Boo Kwang Suck , Yook Hyun Ho , Lee Jong Il , Che Woo Seong
Published: March 2009

This paper describes a method to detect leaks on the surface of a wheel rim manufactured
by aluminum die casting and forging. Leaks in the wheel rim may be caused by temperature
gradient differences during the cooling period, impurities, or flowing air bubbles in the die casting
process. We developed a new low-cost approach to detect leaks that only required a short
inspection time by observing the movement of soap bubbles on the wheel rim surface. We designed
new light sources to minimize mirror image effects and irregular luminance distributions on the
curved wheel rim surface. A preprocessing procedure for image processing was also developed to
determine the bubble configurations using threshold and morphology techniques. A series of
experiments were conducted to evaluate the performance of the inspection system. The results
demonstrated that leaks generated during the wheel rim manufacturing process could be accurately
detected even under various environmental lighting conditions.
Automatic Visual Inspection for Leather Manufacture
Authors: He Fu Qiang , Wang Wen , Chen Zi Chen
Published: March 2009

The visual inspection system was developed for defects detection on leather surfaces,
which is an important component of automatic CAD/CAM cutting systems. The main functions of
the system are quality control and raw material cutting. An efficient algorithm, which combines
multiresolution approach, energy and entropy matrices, is presented for detection of defects
embedded in leather surface images. A wavelet band selection procedure was developed to
automatically determine the number of resolution levels and decompose subimages for the best
discrimination of defects and removals of repetitive texture patterns in the image. An adaptive
binary thresholding is then used to separate the defective regions from the uniform gray-level
background in the restored image. The proposed methodology is able to efficiently detect several
types of defects that current approaches cannot detect, and is fast enough to be used for real-time
leather inspection.
Application of Torsional Mode of Guided Waves to Long Range Pipe Inspection
Authors: Park Ik Keun , Kim Yong Kwon , Song Won Joon , Cho Yong Sang
Published: March 2009

Conventional non-destructive techniques for inspection of weld in pipelines require
significant test time and high cost. In order to overcome these drawbacks in conventional NDT
techniques, various techniques using ultrasonic guided waves have been developed and applied to the
pipeline inspection. Recently, a fast calculation technique for guided wave propagation using a
semi-analytical finite element method (SAFEM), PIPE WAVE ver.1.0, has been developed by T.
Takahiro et al [1]. In this paper, the calculation of torsional mode propagation in a pipe using PIPE
WAVE ver. 1.0 is introduced as a preliminary study and the application of the torsional mode of
ultrasonic guided waves to long range pipe inspection is presented.. The characteristics and setup of a
long range guided wave inspection system and experimental results in pipes of various diameters are
introduced. The experimental results in mock-up pipes with cluster type detects show that the limit of
detectable wall thickness reduction with this guided wave system is 2~3% in the pipe cross section
area and the wall thickness reduction of 5% in cross section area can be detected when actual
detection level is used. Therefore, the applicability of the ultrasonic guided wave technique to long
range pipeline inspection for wall thickness reduction is verified.
Application of Wavelet Transform for Analyzing Instantaneous Contour of Continual Deformation Object
Authors: Chen Fan Xui , He Xiao Yuan
Published: March 2009

The reconstruction of instantaneous contour is a common method to analyze the kinetic
characteristic of a continual deformation object. In this paper a continuous wavelet transform
method (CWT) is applied to analyze the instantaneous contour of a continual deformation object
based on shadow moiré technique. The modulated moiré fringe patterns are captured by use of a
high-speed CCD camera and the temporal intensity variation of each pixel related to the object
deformations is recorded. The intensity variation of each pixel is analyzed along the time axis by
CWT. From the extraction of the ridges and from the value of the CWT along the ridges, the
information of modulated phase relative to the contour of object can be obtained. In this application,
a cantilever beam with a motion in the Z direction is tested by use of the method and the
high-quality instantaneous contour of the continual deformation object can be retrieved.
Experimental results prove that the CWT can successfully be applied to the instantaneous contour
analysis of continual deformation object and these results demonstrate the advantages of the CWT
with respect to the applicable simplicity and the resistance of noise pollution.
The Measurement of Residual Deformation in PBGA Package after Reflow Process Using A Newly Developed Laser Profiler
Authors: Kim Il Ho , Yoon Ji Young , Lee Soon Bok
Published: March 2009

For measuring deformation of electronic packages, various techniques have been used.
Each technique has some merits and demerits. Some techniques have very high resolution but small
measuring area. On the contrary, other techniques have large measuring area and low resolution. So
the judicious selection of techniques with a trade-off between the resolution and available
measuring area is important. In this research, a new laser profiler was developed by integrating high
resolution laser displacement sensor into the x-y scanner. This system has 10nm vertical resolution
and 100nm horizontal resolution with a measurement area up to 25mm by 25mm. The residual
deformation of a lead-contained and lead-free PBGA package after reflow process was measured by
the newly developed system. And the effect of aging was evaluated.
Reliability and Lifetime of Mechanical Units in Operation and Test
Authors: Algin Vladimir B. , Kim Hyoung Eui
Published: March 2009

The paper discusses the problem of reliability calculation for mechanical units under
load. Because the rated reliability of the unit as a system with many independent elements can tend
to zero, the methods of reliability calculation of the units as real objects with the common factors
(loads, operation conditions) are proposed. The choice of the life test modes and test time depends
essentially on unit-related information like their operation conditions. The paper describes one of
approaches, passing to this problem. Within its framework, the accumulations of damages are made
at several typical points of the loaded system.
A Study on the Fatigue Life Prediction and Evaluation of the Natural Rubber Components for Automobile Vehicles
Authors: Woo Chang Su , Kim Wan Doo , Kwon Jae Do
Published: March 2009

The fatigue analysis and lifetime evaluation are very important in design procedure to
assure the safety and reliability of the rubber components. The interest of the fatigue life of rubber
components such as the engine mount is increasing according to the extension of warranty period of
the automotive components. In this study, the fatigue lifetime prediction methodology of the
vulcanized natural rubber was proposed by incorporating the finite element analysis and fatigue
damage parameter determined from fatigue tests. Finite element analysis of 3D dumbbell specimen
of natural rubber was performed based on a hyper-elastic material model determined from the
tension, compression and shear tests. The Green-Lagrange strain at the critical location determined
from the finite element analysis was used for evaluating the fatigue damage parameter of the natural
rubber. Fatigue tests were performed using the 3D dumbbell specimens with different levels of
maximum strain and various load. The basic mechanical properties test and the fatigue test of
rubber specimens under the normal and elevated temperature were conducted. Fatigue life curves
can be effectively represented by a following single function using the maximum Green-Lagrange
strain. Fatigue lives of the natural rubber are predicted by using the fatigue damage parameters at
the critical location. Predicted fatigue lives of the engine mount agreed fairly with the experimental
fatigue lives a factor of two.
Reliability Estimation of Solder Joint by Using the Failure Probability Models
Authors: Lee Ouk Sub , Hur Man Jae , Hawong Jai Sug , Myoung No Hoon , Kim Dong Hyeok
Published: March 2009

The differences in the coefficient of thermal expansion (CTE) between the chip and the
FR-4 board generate the shear strains and the bending moment in the solder joint. It seems to be a
main cause of failure in the solder joint when the chip and the FR-4 board are heated repeatedly.
Thus, the fatigue loading induced by thermal cycling is a major concern in the reliability of the
solder joint. The magnitude of shear strain and the final failure are known to be influenced by
varying boundary conditions such as the difference of CTE, the height of solder, the distance of the
solder joint from the neutral point (DNP) and the temperature variation. In this paper, the effects of
boundary conditions on the failure probability of the solder joint are studied by using the failure
probability models such as the First Order Reliability Method (FORM) and the Monte Carlo
Simulation (MCS). Furthermore, the stiffness of the solder joint is considered to investigate the
influence at the failure probability.
Analysis of Hygrothermal Stress in Polymeric Thin Film Combining Laser Scanning Method and Boundary Element Method
Authors: Lee Sang Soon
Published: March 2009

This paper deals with the hygrothermal stress induced in a polymeric thin film deposited on
Si wafer subjected to the combined influence of temperature change and moisture absorption. The
laser scanning method and the boundary element method (BEM) are employed to investigate the
residual stresses. The film/wafer system is assumed to be linearly elastic. The film/substrate system is
assumed to be stress-free at a temperature of C o 300 and is cooled from a cure temperature down to
room temperature. Then the moisture concentration in the film is increased to the saturation level. The
normal stress across thickness of the thin film is estimated from wafer curvature measurements. The
boundary element method is employed to investigate the whole stresses in the film. The numerical
results for the normal stress across thickness of the film show good agreement with experimental
results obtained by using the laser scanning method. The singular stress is observed near the interface
corner. Such residual stresses are large enough to initiate interface delamination to relieve the residual
stresses.
Residual Deformation Measurement of Laser Weldment Using the Laser Interferometry
Authors: Liu Zhan Wei , Zou Da Qing , Chen Wu Zhu , Wang Wei Ning , Fang Yan
Published: March 2009

In this paper, the residual deformation induced in laser welding processing was studied
by using the moiré interferometry and a novel high-temperature specimen grating technology. The
experimental results indicate that the heat-affected zone of laser welding is a narrow strip. There
exists great residual strain gradient in the heat-affected zone, especially great residual shear strain
gradient. It implies that great residual stress and stress gradient exist near the welded seam. The
relationship between the size of the heat-affected zone and the changes of the technology
parameters were discussed in the experiments, which can supply some reliable experimental data
for optimizing processing technology.
A Study on Speed Elevation Possibility at the Connection between High Speed Lines and Conventional Lines with Korean High Speed Train
Authors: Ham Young Sam , Hong Jai Sung
Published: March 2009

Railways are a mass transportation system with high safety and punctuality. These
strengths have been well proved by tests and evaluations. Railways are an integrated system with
cars, power, signal, communication, line structures and operation. Among many safety standards of
these systems, contact force between wheels and lines can be chosen since a derailment coefficient
evaluated by contract force is the most important fact that decides the safety of railways. Especially
regarding express trains, since they run twice faster than conventional ones, the evaluation of a
derailment coefficient is more important than any other criteria. Currently, Korean express trains
between Seoul and Pusan use the same stations as conventional trains in Daejeon and Dong-Daegu;
therefore, express trains run on conventional lines from express lines. This paper describes test
results acquired by increasing the train speed where express lines and conventional lines are
connected. Test results tell that it is safe with under 0.8 derailment coefficient and running time is
reduced by 10~30 seconds in each section.
Accelerated Life Test Model for Life Prediction of Piston Assemblies in Hydraulic Pump and Motor
Authors: Lee Y.B. , Kim H.E. , Yoo Y.C. , Park J.H.
Published: March 2009

The safety factor of hydraulic piston pumps and motors shows a tendency to decrease due to high
pressurization, high speed and low weight/volume realization to enhance the output density.
Therefore, more effective test models are necessary to predict the exact life. The sensitive
parameters in the endurance life test are speed, pressure and temperature, and failure production
increases in proportion to the operating time. In this research, the authors propose a combined
accelerated life test model using the analysis method of the combined accelerated life test results of
piston-shoe assemblies by simultaneously applying high speed, high pressure and high temperature
in accordance with the variation in speed, pressure and temperature in order to reduce the life test
time.
The Development of a Hollow Cap Thermoplastic Film for Laser Capture Microdissection with a Near Field Fiber Tip
Authors: Chen Chien Ming , Shen Chuan Yu , Chen Yung Chung , Lee Jen Ai
Published: March 2009

Our new constructed LCM system with a near field fiber probe heated the thermoplastic
polymer film which placed above the tissue section by focusing laser beam (810 nm), and this
method improved the resolution of the dissection capture. In this study, we designed a new cap with
a hole, which made the fiber probe exert close melting, and the optimal conditions of making the
thermoplastic film adhere on the cap were also studied. We used a copolymer with ethylene vinyl
acetate (EVA) as the main material of the film and 0.001 M infrared naphthalocyanine dye
dissolved in toluene were added and mixed for spin coating. The thermoplastic film was coated on a
release agent sprayed substrate, and the new cap was placed on the substrate then put into the oven
at 80 for one hour. After cooling to the room temperature, we got the thermoplastic film on the
cap, and we investigated the effect of different thickness of the thermoplastic film. By using the
LCM system with near-field fiber probe, the melted spots have successfully formed on the films,
and the results showed that the melted size is related to the thickness of the film. According to the
results of this study, the fiber probe was workable on the hollow cap with thermoplastic film, and
these provided the further development of the new LCM system in nano-captures.
Hip Joint Control of PGO for Paraplegics
Authors: Kang Sung Jae , Ryu Jei Cheong , Kim Gyoo Suk , Mun Mu Seong
Published: March 2009

In this study, we developed a fuzzy-logic-controlled PGO (Power Gait Othosis) that
controls the flexion and extension of each PGO joint using bio-signals and an FSR sensor. The PGO
driving system works to couple the right and left sides of the orthosis by specially-designed hip
joints and pelvic section. This driving system consists of the orthosis, sensor, and control system.
An air supply system for muscle action is composed of an air compressor, 2-way solenoid valve
(MAC, USA), accumulator and pressure sensor. The role of this system is to provide constant “air
muscle” with compressed air at the hip joint. With the output signal of the EMG and foot sensors,
air muscles assist the flexion of the hip joint during the PGO gait.
Identification of Displacement Field by X-Ray CT
Authors: Yoshikawa Nobuhiro , Kuzukami Shouji , Kuwazuru Osamu
Published: March 2009

A material testing methodology is investigated in line with non-invasive manner using XRay
CT images for characterizing biological tissues. Three-dimensional digital image volumes are
generated for initial and loaded states. Tentative displacement field is represented by basis function
of B-spline. Unknown parameters included in the functions are identified through an inverse
problem minimizing error in terms of pixel intensity between actual deformed image volume and
virtual one according to the tentative displacement field of B-spline. A constraint of
incompressibility affects well for stable and prompt solution search. The proposed methodology is
demonstrated in identification problem of three-dimensional displacement field by using an
experimental data of compressive specimen.
The Effect of Carbonated Apatite Powder Size on Its Embedment into Titanium Alloy by Superplastic Deformation Process
Authors: Ramdan Raden Dadan , Jauhari Iswadi , Hasan Rafidah , Masdek Nik Rozlin Nik , Zakaria Fadzil Ayad , Jamuna K.
Published: March 2009

The effect of carbonated apatite powder size on the carbonated apatite embedded on
titanium alloy was studied. The process was conducted using superplastic deformation method at
750oC and initial pressure of 34MPa. In order to evaluate the characteristics of the resulting
embedded layer, X-ray diffraction method was conducted followed with microstructure
characterization. From X-ray diffraction characterization, it can be concluded that small stress
layers of carbonated apatite were resulted for all samples with different initial powder size. In
addition, initial powder size of carbonated apatite only significantly influences the intensity of
diffraction peak for certain plane of crystal structure. From the experimental results, it can also be
concluded that superplastic deformation can be used as an alternative method for the coating
process of bio apatite material on titanium alloy substrate
The Effect of the Costal Vein Configuration of the Wings of a Dragonfly
Authors: Machida Kenji , Oikawa Tomoaki , Shimanuki Junichi
Published: March 2009

In generally, it is known that structures of living thing are optimized. The wings of a
dragonfly are thin and light. Although it is having the structure of bearing the load produced in the
case of an advanced flight such as “Flapping flight”, “Glide”, and “Hovering”. The wings of a
dragonfly are made by veins and membranes. In addition, the wings of a dragonfly have some
characteristic structures, such as “Nodus”. Thus, the wings of dragonfly have many complicated
structures. The configuration of costal vein of the wings is different from them of other insects. So,
we paid attention to the configuration of costal vein of the wings. Therefore, in this study, we
researched about the effect of costal vein. As a result, it was showed that the configuration of costal
vein became bending and torsional deformation small. In addition, it was showed that the
configuration of costal vein related to nodus. In this study, several 3-D models of the dragonfly’s
wing were made and calculated by the 3-D finite element method.
A Conceptual Model of Micro Inertial Sensor Mimicking Amplifying Mechanism of the Hair Cells
Authors: Lim Ko Eun , Park Suk Yung
Published: March 2009

The inner ear hair cells, the receptors sensing mechanical stimuli such as acoustic
vibration and acceleration, achieve remarkably high sensitivity to miniscule stimuli by selectively
amplifying small inputs. The gating springs hypothesis proposes that a phenomenon called negative
stiffness is responsible for the nonlinear sensitivity. According to the hypothesis, the bundle
becomes more sensitive in certain region as its stiffness changes due to the opening or closing of
transduction channels, which in turn exert force in the same direction of the bundle’s displacement.
In this study, we developed a conceptual model of an inertial sensor inspired by the inner ear hair
cells, focusing on the hair cell’s amplifying mechanism known as negative stiffness. The negative
stiffness was applied to a simple mass-spring-damper system with nonlinear spring derived from
gating springs hypothesis. Sinusoidal stimuli of 0.1Hz~10Hz with magnitude of 1pN to 1000pN
were applied to the system to match the dynamic range of vestibular organs. Simulation on this
nonlinear model was performed on MATLAB, and power transfers and sensitivities in both
transient and steady states were obtained and compared with those from the system with linear
spring. Parameters were chosen in relation to those of the hair bundle to reproduce operating
conditions of both the hair cells and micro inertial sensors. The suggested model displayed
compressive nonlinear sensitivity resulting from selective amplification of smaller stimuli despite
the energy loss due to large viscous damping typical in micro systems.
Image Reconstruction from Incomplete Data and Its Applications in Experimental Mechanics
Authors: Huang Y.H. , Hung Y.Y. , He X.Y. , Liu L.
Published: March 2009

In the field of experimental mechanics, there exist some circumstances when only data at
the boundary can be obtained while the internal data are unavailable, or when some data are missed
due to shadow, illumination saturation and other reasons. Thus it would be helpful if a reasonable
estimation of the unavailable or missed data can be obtained. In this study, an algorithm is
developed to reconstruct the missed data from the existing ones by generating a series of equations
about the missed data and solving for an optimal solution using least-squares approach. Results
based on both simulation data and real incomplete experimental data obtained by shearography and
fringe projection show the usefulness and potential of the algorithm for experimental mechanics
applications.
Effect of Osteoporosis on Natural Frequencies in Mouse Femur: Vibration Test and Micro-CT Based Finite Element Analysis
Authors: Kim Yoon Hyuk , Byun Chang Hwan , Oh Taek Yul
Published: March 2009

In this study, the change of the natural frequencies in mouse femurs with osteoporosis
was investigated based on a vibration test and a finite element. Three groups of the femurs include
the osteoporotic group, the treated group and the normal group. In the vibration test, the natural
frequencies were measured by the mobility test. For the finite element analysis, the micro finite
element model of the femur was reconstructed using the Micro-CT images and the Voxel mesh
generation algorithm. From the results, the averaged natural frequencies in the osteoporotic group
were the highest, followed by those in the treated group. The finite element models were validated
within 15% errors by comparing the natural frequencies in the finite element analysis with those in
the vibration test. The developed Micro-CT system, the Voxel mesh generation algorithm, the
presented finite element analysis, and vibration test could be useful for the investigation of the
structural change of the bone tissue, and the diagnosis and the treatment in the osteoporosis.
Experimental Methods for Three-Dimensional Mixed Mode Fracture
Authors: Dong Hui Ru , Liu Quan Liang , Zhang Zhi Guo , Cheng Yun Xiang
Published: March 2009

Experimental methods that can be used in three-dimensional mixed mode fracture
researches are investigated. The methods are capable of determining the initiation load, maximal
load, crack tip opening displacement, crack tip slipping displacement and initiation angle of the
mixed mode crack simply and conveniently. As an example, the effect of thickness on mixed-mode
I/II fracture of a kind of aluminum alloy is revealed by the methods.
Finite Element Alternating Method for Solving Two-Dimensional Cracks Embedded in a Bimaterial Body
Authors: Park Sang Yun , Park Jai Hak
Published: March 2009

The finite element alternating method based on the superposition principle has been known
as an effective method to obtain the stress intensity factors for general multiple collinear or curvilinear
cracks in an isotropic plate. In this paper the method is extended further to solve two-dimensional
cracks embedded in a bimaterial plate. The main advantage of this method is that it is not necessary to
make crack meshes considering the stress singularity at the crack tip. The solution of the developed
code is obtained from an iteration procedure, which alternates independently between the finite
element method solution for an uncracked body and the analytical solution for cracks in an infinite
body. In order to check the validity of the method, several crack problems of a bimaterial body are
solved and compared with the results obtained from the finite element analysis.
Study of Internal Magnetic Field Assisted Finishing for Copper Tubes with MRF (Magneto-Rheological Fluid)-Based Slurry
Authors: Sato T. , Yamaguchi H. , Shinmura Takeo , Okazaki T.
Published: March 2009

This research studied the internal magnetic field assisted finishing with MRF (Magneto-rheological Fluid)-based slurry for copper tubes.MRF-based slurry that included diamond abrasives was applied to the internal magnetic field assisted finishing for copper tubes and the finishing characteristics were studied. The results showed that the exciting current and the abrasive size changed the finishing characteristics of MRF-based slurry. This finishing process creates a smooth mirror finished surface with few directional cutting marks on the surface of the copper tube.
Research on Material Removal of Magnetorheological Finishing
Authors: Kang Gui Wen , Zhang Fei Hu
Published: March 2009

Magnetorheological finishing (MRF) is a novel precision optical machining technology. Owing to its flexible finishing process, MRF can eliminate subsurface damage, smooth rms micro roughness and correct surface figure errors. The finishing process can be easily controlled by a computer. Material removal model in MRF is established. According to Preston equation in optical machining, mathematic model of material removal rate in MRF rotating at fixed rate is established through hydrodynamic analysis of the MR fluid flow in the polishing zone. The validity of the model is examined by the experimental results.
Experimental Investigation on Honing of Small Holes
Authors: Bai Y.J. , Zhang Lian Hong , Ren Cheng Zu
Published: March 2009

As a special kind of grinding, honing is a typical low speed precision machining process,
which is of low grinding speed, little grinding heat and little thermal-residual deformation of
workpiece, suitable for precision machining of holes in the precision couples of internal-combustion
engine. Experimental investigation on effects of process parameters on honing efficiency of small
holes was put forward in this paper to obtain economical machining efficiency. Circumferential
speed, reciprocate speed and working pressure of honing stone are the key factors which affect the
machining efficiency and quality of honing. Taking it as a case study the honing of the small middle
hole of the valve seat of balancing valve couples of internal combustion engines, honing experiments
were carried out in this paper to investigate the relationships of material removing rate in rough
honing versus circumferential speed, reciprocate speed and working pressure in honing of small
holes. The results show that in honing of small holes the material removal rate in rough honing
increases with circumferential speed, reciprocate speed and reticulate cross-angle increasing but
decreases when the two speeds exceed certain critical values, and the surface quality in finishing
honing is improved by increasing circumferential speed.
Grinding Performance of a Grain-Arranged Diamond Wheel against Industrial Pure Aluminum
Authors: Okuyama Shigeki , Kitajima Takayuki , Yui Akinori
Published: March 2009

A grain-arranged diamond wheel is developed and grinding performance of the wheel
against industrial pure aluminum, one of the most hard-to-grinding materials, is investigated. The
developed wheel efficiently ground pure aluminum without adhesion even when general-purpose
grinding fluid, Type A3-1, was used. Moreover, wheel wear was not observed during the
experiment, and grinding energy was extremely low. By using the developed wheel, a mirror
surface can be easily obtained by one-pass surface grinding with very low table speed.