Abstract: The flow and heat transfer characteristics for natural
convection along an inclined plate in a saturated porous medium with
an applied magnetic field have been studied. The fluid viscosity has
been assumed to be an inverse function of temperature. Assuming
temperature vary as a power function of distance. The transformed
ordinary differential equations have solved by numerical integration
using Runge-Kutta method. The velocity and temperature profile
components on the plate are computed and discussed in detail for
various values of the variable viscosity parameter, inclination angle,
magnetic field parameter, and real constant (λ). The results have also
been interpreted with the aid of tables and graphs. The numerical
values of Nusselt number have been calculated for the mentioned
parameters.
Abstract: An experiment of vented gas explosions involving two
different cylinder vessel volumes (0.2 and 0.0065 m3) was reported,
with equivalence ratio (Φ) ranged from 0.3 to 1.6. Both vessels were
closed at the rear end and fitted at the other side with a circular
orifice plate that gives a constant vent coefficient (K =Av/V2/3) of
16.4. It was shown that end ignition gives higher overpressures than
central ignition, even though most of the published work on venting
uses central ignition. For propane and ethylene, it is found that rich
mixtures gave the highest overpressures and these mixtures are not
considered in current vent design guidance; which the guideline is
based on mixtures giving the maximum flame temperature. A strong
influence of the vessel volume at constant K was found for methane,
propane, ethylene and hydrogen-air explosions. It can be concluded
that self- acceleration of the flame, which is dependent on the
distance of a flame from the ignition and the ‘suction’ at the vent
opening are significant factors affecting the vent flow during
explosion development in vented gas explosion. This additional
volume influence on vented explosions is not taken into account in
the current vent design guidance.
Abstract: This paper reports an experimental study on a sleeping
thermal manikin in a room equipped with a mixing ventilation
system. In the experimental work, heat loss from the sleeping thermal
manikin was measured under different conditions. The supply air
temperature was in a range of 17°C to 27°C. Apart from the heat loss
of the sleeping thermal manikin, the velocity distributions and
temperature distributions were also measured in the experiments for
subsequent analysis.
Abstract: The aim of the present investigation was to compare
sex differences in thyroid gland structure of rabbits. Five adult male
and five adult female (3.1-3.5 kg body weight) New Zealand white
rabbits were used in the experiment. Results showed that at light
microscopic level, there was no sex difference in microscopic
appearance of the thyroid glands. At electron microscopic level,
however, the mitochondria and the microvilli of the follicular cells
are more numerous and the Golgi complex is also more extensive in
male rabbits in comparison to females. Results obtained from
micrometric measurements showed that the volume density of the
follicles is higher in males than in females, but the differences are not
statistically significant .The volume density of epithelium and the
height of follicular cells are significantly greater in males than in
females and reverse is true about the volume density of interstitium
(p
Abstract: The current speech interfaces in many military
applications may be adequate for native speakers. However,
the recognition rate drops quite a lot for non-native speakers
(people with foreign accents). This is mainly because the nonnative
speakers have large temporal and intra-phoneme
variations when they pronounce the same words. This
problem is also complicated by the presence of large
environmental noise such as tank noise, helicopter noise, etc.
In this paper, we proposed a novel continuous acoustic feature
adaptation algorithm for on-line accent and environmental
adaptation. Implemented by incremental singular value
decomposition (SVD), the algorithm captures local acoustic
variation and runs in real-time. This feature-based adaptation
method is then integrated with conventional model-based
maximum likelihood linear regression (MLLR) algorithm.
Extensive experiments have been performed on the NATO
non-native speech corpus with baseline acoustic model trained
on native American English. The proposed feature-based
adaptation algorithm improved the average recognition
accuracy by 15%, while the MLLR model based adaptation
achieved 11% improvement. The corresponding word error
rate (WER) reduction was 25.8% and 2.73%, as compared to
that without adaptation. The combined adaptation achieved
overall recognition accuracy improvement of 29.5%, and
WER reduction of 31.8%, as compared to that without
adaptation.
Abstract: Circular tubes have been widely used as structural
members in engineering application. Therefore, its collapse behavior
has been studied for many decades, focusing on its energy absorption
characteristics. In order to predict the collapse behavior of members,
one could rely on the use of finite element codes or experiments.
These tools are helpful and high accuracy but costly and require
extensive running time. Therefore, an approximating model of tubes
collapse mechanism is an alternative for early step of design. This
paper is also aimed to develop a closed-form solution of thin-walled
circular tube subjected to bending. It has extended the Elchalakani et
al.-s model (Int. J. Mech. Sci.2002; 44:1117-1143) to include the
rate of energy dissipation of rolling hinge in the circumferential
direction. The 3-D geometrical collapse mechanism was analyzed by
adding the oblique hinge lines along the longitudinal tube within the
length of plastically deforming zone. The model was based on the
principal of energy rate conservation. Therefore, the rates of internal
energy dissipation were calculated for each hinge lines which are
defined in term of velocity field. Inextensional deformation and
perfect plastic material behavior was assumed in the derivation of
deformation energy rate. The analytical result was compared with
experimental result. The experiment was conducted with a number of
tubes having various D/t ratios. Good agreement between analytical
and experiment was achieved.
Abstract: The present work describes an experimental
investigation concerning the determination of viscosity behavior with
shear rate and temperature of edible oils: canola; sunflower; corn;
soybean and the no edible oil: Jatropha curcas. Besides these, it was
tested a blend of canola, corn and sunflower oils as well as sunflower
and soybean biodiesel. Based on experiments, it was obtained shear
stress and viscosity at different shear rates of each sample at 40ºC, as
well as viscosity of each sample at various temperatures in the range
of 24 to 85ºC. Furthermore, it was compared the curves obtained for
the viscosity versus temperature with the curves obtained by
modeling the viscosity dependency on temperature using the Vogel
equation. Also a test in a stationary engine was performed in order to
study the energy generation using blends of soybean oil and soybean
biodiesel with diesel.
Abstract: This paper explores the use of project work in a
content-based instruction in a Rajabhat University, a teacher college,
where student teachers are instructed to perform teaching roles
mainly in basic education level. Its aim is to link theory to practice,
and to help language teachers maximize the full potential of project
work for genuine communication and give real meaning to writing
activity. Two research questions are formulated to guide this study:
a) What is the academic achievement of the students- writing skill
against the 70% attainment target after the use of project to enhance
the skill? and b) To what degree is the development of the students-
writing skills during the course of project to enhance the skill? The
sample of the study comprised of 38 fourth-year English major
students. The data was collected by means of achievement test,
student writing works, and project diary. The scores in the summative
achievement test were analyzed by mean score, standard deviation,
and t-test. Project diary serves as students- record of the language
acquired during the project. List of structures and vocabulary noted in
the diary has shown students- ability to attend to, recognize, and
focus on meaningful patterns of language forms.
Abstract: In recent years, the underground water sources in
southern Taiwan have become salinized because of saltwater
intrusions. This study explores the adsorption characteristics of
activated carbon on salinizing inorganic salts using isothermal
adsorption experiments and provides a model analysis. The
temperature range for the isothermal adsorption experiments ranged
between 5 to 45 ℃, and the amount adsorbed varied between 28.21 to
33.87 mg/g. All experimental data of adsorption can be fitted to both
the Langmuir and the Freundlich models. The thermodynamic
parameters for per chlorate onto granular activated carbon were
calculated as -0.99 to -1.11 kcal/mol for DG°, -0.6 kcal/mol for DH°,
and 1.21 to 1.84 kcal/mol for DS°. This shows that the adsorption
process of granular activated carbon is spontaneously exothermic. The
observation of adsorption behaviors under low ionic strength, low pH
values, and low temperatures is beneficial to the adsorption removal of
perchlorate with granular activated carbon.
Abstract: The product development process (PDP) in the
Technology group plays a very important role in the launch of any
product. While a manufacturing process encourages the use of certain
measures to reduce health, safety and environmental (HSE) risks on
the shop floor, the PDP concentrates on the use of Geometric
Dimensioning and Tolerancing (GD&T) to develop a flawless design.
Furthermore, PDP distributes and coordinates activities between
different departments such as marketing, purchasing, and
manufacturing. However, it is seldom realized that PDP makes a
significant contribution to developing a product that reduces HSE
risks by encouraging the Technology group to use effective GD&T.
The GD&T is a precise communication tool that uses a set of
symbols, rules, and definitions to mathematically define parts to be
manufactured. It is a quality assurance method widely used in the oil
and gas sector. Traditionally it is used to ensure the
interchangeability of a part without affecting its form, fit, and
function. Parts that do not meet these requirements are rejected
during quality audits.
This paper discusses how the Technology group integrates this
quality assurance tool into the PDP and how the tool plays a major
role in helping the HSE department in its goal towards eliminating
HSE incidents. The PDP involves a thorough risk assessment and
establishes a method to address those risks during the design stage.
An illustration shows how GD&T helped reduce safety risks by
ergonomically improving assembling operations. A brief discussion
explains how tolerances provided on a part help prevent finger injury.
This tool has equipped Technology to produce fixtures, which are
used daily in operations as well as manufacturing. By applying
GD&T to create good fits, HSE risks are mitigated for operating
personnel. Both customers and service providers benefit from
reduced safety risks.
Abstract: Bionanotechnology deals with nanoscopic interactions between nanostructured materials and biological systems. Polymer nanocomposites with optimized biological activity have attracted great attention. Nanoclay is considered as reinforcing nanofiller in manufacturing of high performance nanocomposites. In current study, organomodified-nanoclay with negatively charged silicate layers was incorporated into biomedical grade silicone rubber. Nanoparticle loading has been tailored to enhance cell behavior. Addition of nanoparticles led to improved mechanical properties of substrate with enhanced strength and stiffness while no toxic effects was observed. Results indicated improved viability and proliferation of cells by addition of nanofillers. The improved mechanical properties of the matrix result in proper cell response through adjustment and arrangement of cytoskeletal fibers. Results can be applied in tissue engineering when enhanced substrates are required for improvement of cell behavior for in vivo applications.
Abstract: In this paper we proposed the use of Huffman
coding to reduce the PAR of an OFDM system as a distortionless
scrambling technique, and we utilize the amount saved in the
total bit rate by the Huffman coding to send the encoding table
for accurate decoding at the receiver without reducing the
effective throughput. We found that the use of Huffman coding
reduces the PAR by about 6 dB. Also we have investigated the
effect of PAR reduction due to Huffman coding through testing
the spectral spreading and the inband distortion due to HPA with
different IBO values. We found a complete match of our
expectation from the proposed solution with the obtained
simulation results.
Abstract: The wave function at the origin is an important quantity in studying many physical problems concerning heavy quarkonia. This is because that it is using for calculating spin state hyperfine splitting and also crucial to evaluating the production and decay amplitude of the heavy quarkonium. In this paper, we present the variational method by using the single-parameter wave function to estimate the WFO for the ground state of heavy mesons.
Abstract: The purpose of this article is to introduce an advanced
system for the support of processing of medical image information,
and the terminology related to this system, which can be an important
element to a faster transition to a fully digitalized hospital.
The core of the system is a set of DICOM compliant applications
running over a dedicated computer network. The whole integrated
system creates a collaborative platform supporting daily routines in
the radiology community, developing communication channels,
supporting the exchange of information and special consultations
among various medical institutions as well as supporting medical
training for practicing radiologists and medical students. It gives the
users outside of hospitals the tools to work in almost the same
conditions as in the radiology departments.
Abstract: The density estimates considered in this paper comprise
a base density and an adjustment component consisting of a linear
combination of orthogonal polynomials. It is shown that, in the
context of density approximation, the coefficients of the linear combination
can be determined either from a moment-matching technique
or a weighted least-squares approach. A kernel representation of
the corresponding density estimates is obtained. Additionally, two
refinements of the Kronmal-Tarter stopping criterion are proposed
for determining the degree of the polynomial adjustment. By way of
illustration, the density estimation methodology advocated herein is
applied to two data sets.
Abstract: Recently, with the appearance of smart cards, many
user authentication protocols using smart card have been proposed to
mitigate the vulnerabilities in user authentication process. In 2004,
Das et al. proposed a ID-based user authentication protocol that is
secure against ID-theft and replay attack using smart card. In 2009,
Wang et al. showed that Das et al.-s protocol is not secure to randomly
chosen password attack and impersonation attack, and proposed an
improved protocol. Their protocol provided mutual authentication and
efficient password management. In this paper, we analyze the security
weaknesses and point out the vulnerabilities of Wang et al.-s protocol.
Abstract: Nuts are part of a healthy diet such as Mediterranean diet. Benefits of nuts in reducing the risk of heart disease has been reasonably attributed to their composition of vitamins, minerals, unsaturated fatty acids, fiber and phytochemicals such as polyphenols, tocopherols, squalene and phytosterols. More than 75% of total fatty acids of nuts are unsaturated. α- tocopherol is the main tocopherol isomer present in most of the nuts. While walnuts, Brazil nut, cashew nut, peanut, pecan and pistachio nuts are rich in γ- tocopherol. β- sitosterol is dominant sterol in nuts. Pistachio and pine nut have the highest total phytosterol and Brazil nut and English walnut the lowest. Walnuts also contain large amount of phenolic compounds compared with other nuts. Nuts are rich in compounds with antioxidant properties and their consumption can offer preventing from incidence of many diseases including cardiovascular.
Abstract: Equilibrium and rate based models have been applied
in the simulation of methyl tertiary-butyl ether (MTBE) synthesis
through reactive distillation. Temperature and composition profiles
were compared for both the models and found that both the profiles
trends, though qualitatively similar are significantly different
quantitatively. In the rate based method (RBM), multicomponent
mass transfer coefficients have been incorporated to describe
interphase mass transfer. MTBE mole fraction in the bottom stream is
found to be 0.9914 in the Equilibrium Model (EQM) and only 0.9904
for RBM when the same column configuration was preserved. The
individual tray efficiencies were incorporated in the EQM and
simulations were carried out. Dynamic simulation have been also
carried out for the two column configurations and compared.
Abstract: The present work describes a computational study of
aerodynamic characteristics of GLC305 airfoil clean and with 16.7
min ice shape (rime 212) and 22.5 min ice shape (glaze 944).The
performance of turbulence models SA, Kε, Kω Std, and Kω SST
model are observed against experimental flow fields at different
Mach numbers 0.12, 0.21, 0.28 in a range of Reynolds numbers
3x106, 6x106, and 10.5x106 on clean and iced aircraft airfoil
GLC305. Numerical predictions include lift, drag and pitching
moment coefficients at different Mach numbers and at different angle
of attacks were done. Accuracy of solutions with respect to the
effects of turbulence models, variation of Mach number, initial
conditions, grid resolution and grid spacing near the wall made the
study much sensitive. Navier Stokes equation based computational
technique is used. Results are very close to the experimental results.
It has seen that SA and SST models are more efficient than Kε and
Kω standard in under study problem.
Abstract: Gas condensate Reservoirs show complicated thermodynamic behavior when their pressure reduces to under dew point pressure. Condensate blockage around the producing well cause significant reduction of production rate as well bottom-hole pressure drops below saturation pressure. The main objective of this work was to examine the well test analysis of naturally fractured lean gas condensate reservoir and investigate the effect of condensate formed around the well-bore on behavior of single phase pseudo pressure and its derivative curves. In this work a naturally fractured lean gas condensate reservoir is simulated with compositional simulator. Different sensitivity analysis done on Corry parameters and result of simulator is feed to analytical well testing software. For consideration of these phenomena eighteen compositional models with Capillary number effect are constructed. Matrix relative permeability obeys Corry relative permeability and relative permeability in fracture is linear. Well testing behavior of these models are studied and interpreted. Results show different sensitivity analysis on relative permeability of matrix does not have strong effect on well testing behavior even most part of the matrix around the well is occupied with condensate.