Abstract: Complex lifting entry was selected for precise landing
performance during the Mars Science Laboratory entry. This study
aims to develop the three-dimensional numerical method for precise
computation and the surface panel method for rapid engineering
prediction. Detailed flow field analysis for Mars exploration mission
was performed by carrying on a series of fully three-dimensional
Navier-Stokes computations. The static aerodynamic performance was
then discussed, including the surface pressure, lift and drag coefficient,
lift-to-drag ratio with the numerical and engineering method.
Computation results shown that the shock layer is thin because of
lower effective specific heat ratio, and that calculated results from both
methods agree well with each other, and is consistent with the
reference data. Aerodynamic performance analysis shows that CG
location determines trim characteristics and pitch stability, and certain
radially and axially shift of the CG location can alter the capsule lifting
entry performance, which is of vital significance for the aerodynamic
configuration design and inner instrument layout of the Mars entry
capsule.
Abstract: Steady three-dimensional and two free surface waves
generated by moving bodies are presented, the flow problem to be
simulated is rich in complexity and poses many modeling challenges
because of the existence of breaking waves around the ship hull, and
because of the interaction of the two-phase flow with the turbulent
boundary layer. The results of several simulations are reported. The
first study was performed for NACA0012 of hydrofoil with different
meshes, this section is analyzed at h/c= 1, 0345 for 2D. In the second
simulation a mathematically defined Wigley hull form is used to
investigate the application of a commercial CFD code in prediction of
the total resistance and its components from tangential and normal
forces on the hull wetted surface. The computed resistance and wave
profiles are used to estimate the coefficient of the total resistance for
Wigley hull advancing in calm water under steady conditions. The
commercial CFD software FLUENT version 12 is used for the
computations in the present study. The calculated grid is established
using the code computer GAMBIT 2.3.26. The shear stress k-ωSST
model is used for turbulence modeling and the volume of fluid
technique is employed to simulate the free-surface motion. The
second order upwind scheme is used for discretizing the convection
terms in the momentum transport equations, the Modified HRIC
scheme for VOF discretization. The results obtained compare well
with the experimental data.
Abstract: Copper (I) oxide microparticles with the morphology
of cubic and hollow sphere were synthesized with the assistance of
surfactant as the shape controller. Both particles were then subjected
to study the catalytic activity and observed the results of shape effects
of catalysts on rate of catalytic reaction. The decolorizing reaction of
crystal violet and sodium hydroxide was chosen and measured the
decreasing of reactant with respect to times using spectrophotometer.
The result revealed that morphology of crystal had no effect on the
catalytic activity for crystal violet reaction but contributed to total
surface area predominantly.
Abstract: Nowadays, the rapid development of CAD systems’
programming environments results in the creation of multiple
downstream applications, which are developed and becoming
increasingly available. CAD based manufacturing simulations is
gradually following the same trend. Drilling is the most popular holemaking
process used in a variety of industries. A specially built piece
of software that deals with the drilling kinematics is presented. The
cutting forces are calculated based on the tool geometry, the cutting
conditions and the tool/work-piece materials. The results are verified
by experimental work. Finally, the response surface methodology
(RSM) is applied and mathematical models of the total thrust force
and the thrust force developed because of the main cutting edges are
proposed.
Abstract: This paper participates in giving new vision and
explains the learning and acquisition processes of English language
by analyzing a certain context. Five important factors in English
language acquisition and learning are discussed and suitable solutions
are provided. The factors are compared with the learners' linguistic
background at Bisha College of Technology BCT attempting to link
the issues faced by students and the research done on similar
situations. These factors are phonology, age of acquisition,
motivation, psychology and courses of English. These factors are
very important; because they interfere and affect specific learning
processes at BCT context and general English learning situations.
Abstract: Steady three-dimensional and two free surface waves
generated by moving bodies are presented, the flow problem to be
simulated is rich in complexity and poses many modeling challenges
because of the existence of breaking waves around the ship hull, and
because of the interaction of the two-phase flow with the turbulent
boundary layer. The results of several simulations are reported. The
first study was performed for NACA0012 of hydrofoil with different
meshes, this section is analyzed at h/c= 1, 0345 for 2D. In the second
simulation a mathematically defined Wigley hull form is used to
investigate the application of a commercial CFD code in prediction of
the total resistance and its components from tangential and normal
forces on the hull wetted surface. The computed resistance and wave
profiles are used to estimate the coefficient of the total resistance for
Wigley hull advancing in calm water under steady conditions. The
commercial CFD software FLUENT version 12 is used for the
computations in the present study. The calculated grid is established
using the code computer GAMBIT 2.3.26. The shear stress k-ωSST
model is used for turbulence modeling and the volume of fluid
technique is employed to simulate the free-surface motion. The
second order upwind scheme is used for discretizing the convection
terms in the momentum transport equations, the Modified HRIC
scheme for VOF discretization. The results obtained compare well
with the experimental data.
Abstract: To ensure targeting of apoferritin nanocarrier with
encapsulated doxorubicin drug, we used a peptide linker based on a
protein G with N-terminus affinity towards Fc region of antibodies.
To connect the peptide to the surface of apoferritin, the C-terminus of
peptide was made of cysteine with affinity to gold. The surface of
apoferritin with encapsulated doxorubicin (APODOX) was coated
either with gold nanoparticles (APODOX-Nano) or gold(III) chloride
hydrate reduced with sodium borohydride (APODOX-HAu). The
reduction with sodium borohydride caused a loss of doxorubicin
fluorescent properties and probably accompanied with the loss of its
biological activity. Fluorescent properties of APODOX-Nano were
similar to the unmodified APODOX; therefore it was more suited for
the intended use. To evaluate the specificity of apoferritin modified
with antibodies, ELISA-like method was used with the surface of
microtitration plate wells coated by the antigen (goat anti-human IgG
antibodies). To these wells, the nanocarrier was applied. APODOX
without the modification showed 5× lower affinity to the antigen than
APODOX-Nano modified gold and targeting antibodies (human IgG
antibodies).
Abstract: In the past decade, the use of digital image correlation
(DIC) techniques has increased significantly in the area of
experimental mechanics, especially for materials behavior
characterization. This non-contact tool enables full field displacement
and strain measurements over a complete region of interest. The DIC
algorithm requires a random contrast pattern on the surface of the
specimen in order to perform properly. To create this pattern, the
specimen is usually first coated using a white matt paint. Next, a
black random speckle pattern is applied using any suitable method. If
the applied paint coating is too thick, its top surface may not be able
to exactly follow the deformation of the specimen, and consequently,
the strain measurement might be underestimated. In the present
article, a study of the influence of the paint thickness on the strain
underestimation is performed for different strain levels. The results
are then compared to typical paint coating thicknesses applied by
experienced DIC users. A slight strain underestimation was observed
for paint coatings thicker than about 30μm. On the other hand, this
value was found to be uncommonly high compared to coating
thicknesses applied by DIC users.
Abstract: To mitigate the urban heat island effect has become a
global issue when we are faced with the challenge of climate change.
Through literature review, plant photosynthesis can reduce the carbon
dioxide and mitigate the urban heat island effect to a degree. Because
there are not enough open space and parks, green roof has become an
important policy in Taiwan.
We selected elementary school buildings in northern New Taipei
City as research subjects since elementary schools are asked with
priority to build green roof and important educational place to promote
green roof concept. Testo175-H1 recording device was used to record
the temperature and humidity differences between roof surface and
interior space below roof with and without green roof in the long-term.
We also use questionnaires to investigate the awareness of comfort
level of green roof and sensation of teachers and students of the
elementary schools.
The results indicated that the temperature of roof without greening
was higher than that with greening by about 2°C. But sometimes
during noontime, the temperature of green roof was higher than that of
non-green roof probably because of the character of the accumulation
and dissipation of heat of greening. The temperature of the interior
space below green roof was normally lower than that without green
roof by about 1°C, showing that green roof could lower the
temperature. The humidity of the green roof was higher than the one
without greening also indicated that green roof retained water better.
Teachers liked to combine green roof concept in the curriculum,
and students wished all classes can take turns to maintain the green
roof. Teachers and students whose school had integrated green roof
concept in the curriculum were more willing to participate in the
maintenance work of green roof. Teachers and students who may have
access to and touch the green roof can be more aware of the green roof
benefit. We suggest architects to increase the accessibility and
visibility of green roof, such as use it as a part of the activity space.
This idea can be a reference to the green roof curriculum design.
Abstract: This paper discusses the forensic investigation of a
fatality-involved catastrophic structure collapse and the special
challenges faced when tasked with directing such an effort. While
this paper discusses the investigation’s findings and the outcome of
the event; this paper’s primary focus is on the challenges faced
directing a forensic investigation that requires coordinating with
governmental oversight while also having to accommodate multiple
parties’ investigative teams. In particular the challenges discussed
within this paper included maintaining on-site safety and operations
while accommodating outside investigator’s interests. In addition this
paper discusses unique challenges that one may face such as what to
do about unethical conduct of interested party’s investigative teams,
“off the record” sharing of information, and clandestinely transmitted
evidence.
Abstract: In the present research work we present the optical
emission studies of the Indium (In) – Tin (Sn) plasma produced by
the first (1064 nm) harmonic of an Nd: YAG nanosecond pulsed
laser. The experimentally observed line profiles of neutral Indium (In
I) and Tin (SnI) are used to extract the electron temperature (Te)
using the Boltzmann plot method. Whereas, the electron number
density (Ne) has been determined from the Stark broadening line
profile method. The Te is calculated by varying the distance from the
target surface along the line of propagation of plasma plume and also
by varying the laser irradiance. Beside we have studied the variation
of Ne as a function of laser irradiance as well as its variation with
distance from the target surface.
Abstract: Development of new generation bio-tribological,
multilayer coatings opens an avenue for fabrication of future hightech
functional surfaces. In the presented work, nano-composite,
Cr/CrN+[Cr/ a-C:H implanted by metallic nanocrystals] multilayer
coatings have been developed for surface protection of medical tools.
Thin films were fabricated by a hybrid Pulsed Laser Deposition
technique. Complex microstructure analysis of nanomultilayer
coatings, subjected to mechanical and biological tests, were
performed by means of transmission electron microscopy (TEM).
Microstructure characterization revealed the layered arrangement of
Cr23C6 nanoparticles in multilayer structure. Influence of deposition
conditions on bio-tribological properties of the coatings was studied.
The bio-tests were used as a screening tool for the analyzed
nanomultilayer coatings before they could be deposited on medical
tools. Bio-medical tests were done using fibroblasts. The mechanical
properties of the coatings were investigated by means of a ball-ondisc
mechanical test. The micro hardness was done using Berkovich
indenter. The scratch adhesion test was done using Rockwell
indenter. From the bio-tribological point of view, the optimal
properties had the C106_1 material.
Abstract: Atmospheric carbon dioxide emissions are considered
as the greatest environmental challenge the world is facing today.
The tasks to control the emissions include the recovery of CO2 from
flue gas. This concern has been improved due to recent advances in
materials process engineering resulting in the development of
inorganic gas separation membranes with excellent thermal and
mechanical stability required for most gas separations. This paper,
therefore, evaluates the performance of a highly selective inorganic
membrane for CO2 recovery applications. Analysis of results
obtained is in agreement with experimental literature data. Further
results show the prediction performance of the membranes for gas
separation and the future direction of research. The materials
selection and the membrane preparation techniques are discussed.
Method of improving the interface defects in the membrane and its
effect on the separation performance has also been reviewed and in
addition advances to totally exploit the potential usage of this
innovative membrane.
Abstract: WO3/SiO2 catalysts were modified by an ion exchange
method with sodium hydroxide or potassium hydroxide solution. The
performance of the modified catalysts was tested in the metathesis of
ethylene and trans-2-butene to propylene. During ion exchange,
sodium and potassium ions played different roles. Sodium modified
catalysts revealed constant trans-2-butene conversion and propylene
selectivity when the concentrations of sodium in the solution were
varied. In contrast, potassium modified catalysts showed reduction of
the conversion and increase of the selectivity. From these results,
potassium hydroxide may affect the transformation of tungsten oxide
active species, resulting in the decrease in conversion whereas
sodium hydroxide did not. Moreover, the modification of catalysts by
this method improved the catalyst stability by lowering the amount of
coke deposited on the catalyst surface.
Abstract: This paper deals with the study of reflection and
transmission characteristics of acoustic waves at the interface of a
semiconductor half-space and elastic solid. The amplitude ratios
(reflection and transmission coefficients) of reflected and transmitted
waves to that of incident wave varying with the incident angles have
been examined for the case of quasi-longitudinal wave. The special
cases of normal and grazing incidence have also been derived with
the help of Gauss elimination method. The mathematical model
consisting of governing partial differential equations of motion and
charge carriers’ diffusion of n-type semiconductors and elastic solid
has been solved both analytically and numerically in the study. The
numerical computations of reflection and transmission coefficients
has been carried out by using MATLAB programming software for
silicon (Si) semiconductor and copper elastic solid. The computer
simulated results have been plotted graphically for Si
semiconductors. The study may be useful in semiconductors,
geology, and seismology in addition to surface acoustic wave (SAW)
devices.
Abstract: Driver fatigue is an important factor in the increasing
number of road accidents. Dynamic template matching method was
proposed to address the problem of real-time driver fatigue detection
system based on eye-tracking. An effective vision based approach
was used to analyze the driver’s eye state to detect fatigue. The driver
fatigue system consists of Face detection, Eye detection, Eye
tracking, and Fatigue detection. Initially frames are captured from a
color video in a car dashboard and transformed from RGB into YCbCr
color space to detect the driver’s face. Canny edge operator was used
to estimating the eye region and the locations of eyes are extracted.
The extracted eyes were considered as a template matching for eye
tracking. Edge Map Overlapping (EMO) and Edge Pixel Count
(EPC) matching function were used for eye tracking which is used to
improve the matching accuracy. The pixel of eyeball was tracked
from the eye regions which are used to determine the fatigue state of
the driver.
Abstract: This paper examines the system protection for cyber-physical
systems (CPS). CPS are particularly characterized by their
networking system components. This means they are able to adapt to
the needs of their users and its environment. With this ability, CPS
have new, specific requirements on the protection against anti-counterfeiting,
know-how loss and manipulation. They increase the
requirements on system protection because piracy attacks can be
more diverse, for example because of an increasing number of
interfaces or through the networking abilities. The new requirements
were identified and in a next step matched with existing protective
measures. Due to the found gap the development of new protection
measures has to be forced to close this gap. Moreover a comparison
of the effectiveness between selected measures was realized and the
first results are presented in this paper.
Abstract: Optical biosensors have become a powerful detection
and analysis tool for wide-ranging applications in biomedical research,
pharmaceuticals and environmental monitoring. This study carried out
the computational fluid dynamics (CFD)-based simulations to explore
the dispersion phenomenon in the micro channel of an optical
biosensor. The predicted time sequences of concentration contours
were utilized to better understand the dispersion development occurred
in different geometric shapes of micro channels. The simulation results
showed the surface concentrations at the sensing probe (with the best
performance of a grating coupler) in respect of time to appraise the
dispersion effect and therefore identify the design configurations
resulting in minimum dispersion.
Abstract: Water miscible cutting fluids are conventionally used to lubricate and cool the machining zone. But issues related to health hazards, maintenance and disposal costs have limited their usage, leading to application of Minimum Quantity Lubrication (MQL). To increase the effectiveness of MQL, nanocutting fluids are proposed. In the present work, water miscible nanographite cutting fluids of varying concentration are applied at cutting zone by two systems A and B. System A utilizes high pressure air and supplies cutting fluid at a flow rate of 1ml/min. System B uses low pressure air and supplies cutting fluid at a flow rate of 5ml/min. Their performance in machining is evaluated by measuring cutting temperatures, tool wear, cutting forces and surface roughness and compared with dry machining and flood machining. Application of nanocutting fluid using both systems showed better performance than dry machining. Cutting temperatures and cutting forces obtained by both techniques are more than flood machining. But tool wear and surface roughness showed improvement compared to flood machining. Economic analysis has been carried out in all the cases to decide the applicability of the techniques.
Abstract: Cerebellar ataxia is a steadily progressive
neurodegenerative disease associated with loss of motor control,
leaving patients unable to walk, talk, or perform activities of daily
living. Direct motor instruction in cerebella ataxia patients has limited
effectiveness, presumably because an inappropriate closed-loop
cerebellar response to the inevitable observed error confounds motor
learning mechanisms. Could the use of EEG based BCI provide
advanced biofeedback to improve motor imagery and provide a
“backdoor” to improving motor performance in ataxia patients? In
order to determine the feasibility of using EEG-based BCI control in
this population, we compare the ability to modulate mu-band power
(8-12 Hz) by performing a cued motor imagery task in an ataxia
patient and healthy control.