Abstract: The spindle system is one of the most important
components of machine tool. The dynamic properties of the spindle
affect the machining productivity and quality of the work pieces.
Thus, it is important and necessary to determine its dynamic
characteristics of spindles in the design and development in order to
avoid forced resonance. The finite element method (FEM) has been
adopted in order to obtain the dynamic behavior of spindle system.
For this reason, obtaining the Campbell diagrams and determining the
critical speeds are very useful to evaluate the spindle system
dynamics. The unbalance response of the system to the center of
mass unbalance at the cutting tool is also calculated to investigate the
dynamic behavior. In this paper, we used an ANSYS Parametric
Design Language (APDL) program which based on finite element
method has been implemented to make the full dynamic analysis and
evaluation of the results. Results show that the calculated critical
speeds are far from the operating speed range of the spindle, thus, the
spindle would not experience resonance, and the maximum
unbalance response at operating speed is still with acceptable limit.
ANSYS Parametric Design Language (APDL) can be used by spindle
designer as tools in order to increase the product quality, reducing
cost, and time consuming in the design and development stages.
Abstract: The microstrip antennas area has seen some inventive
work in recent years and is now one of the most dynamic fields of
antenna theory. A novel and simple wideband monopole antenna is
presented printed on a single dielectric substrate which is fed by a 50
ohm microstrip line having a low-profile antenna structure with two
parallel s-shaped meandered line of same size. This antenna is fed by
a coaxial feeding tube. In this research, S–form microstrip patch antenna is designed from
measuring the prototypes of the proposed antenna one available
bands with 10db return loss bandwidths of about GPS application
(GPS L2 1490 MHz) and covering the 1400 to 1580 MHz frequency
band at 1.5 GHz, the simulated results for main parameters such as
return loss, impedance bandwidth, radiation patterns, and gains are
also discussed herein. The modeling study shows that such antennas,
in simplicity design and supply, can satisfy GPS application. Two
parallel slots are incorporated to disturb the surface flow path,
introducing local inductive effect. This antenna is fed by a coaxial
feeding tube.
Abstract: In this communication, a low-cost circularly
polarized wire antenna exhibiting improved gain performance for
Dedicated Short Range Communications (DSRC), vehicle-to-vehicle
(V2V) and vehicle-to-infrastructure (V2I) communications is
presented. The proposed antenna comprises a Y-shaped quarterwavelength
monopole antenna surrounded by two iterations of eight
conductive arched walls acting as parasitic elements to enhance the
overall antenna gain and to shape the radiation pattern in the H-plane.
A hemispherical radome shell is added to protect the antenna
structure and its effect on the antenna performance is discussed. The
designed antenna demonstrates antenna gain of 8.2 dB with
omnidirectional far-field radiation pattern in the H-plane. The gain of
the proposed antenna is also compared with the characteristic of the
stand-alone Y-shaped monopole to highlight the advantages of the
proposed approach.
Abstract: This study analyzes the critical gaps in the
architecture of European stability and the expected role of the
banking union as the new important step towards completing the
Economic and Monetary Union that should enable the creation of
safe and sound financial sector for the euro area market. The single
rulebook together with the Single Supervisory Mechanism and the
Single Resolution Mechanism - as two main pillars of the banking
union, should provide a consistent application of common rules and
administrative standards for supervision, recovery and resolution of
banks – with the final aim of replacing the former bail-out practice
with the bail-in system through which possible future bank failures
would be resolved by their own funds, i.e. with minimal costs for
taxpayers and real economy. In this way, the vicious circle between
banks and sovereigns would be broken. It would also reduce the
financial fragmentation recorded in the years of crisis as the result of
divergent behaviors in risk premium, lending activities and interest
rates between the core and the periphery. In addition, it should
strengthen the effectiveness of monetary transmission channels, in
particular the credit channels and overflows of liquidity on the money
market which, due to the fragmentation of the common financial
market, has been significantly disabled in period of crisis. However,
contrary to all the positive expectations related to the future
functioning of the banking union, major findings of this study
indicate that characteristics of the economic system in which the
banking union will operate should not be ignored. The euro area is an
integration of strong and weak entities with large differences in
economic development, wealth, assets of banking systems, growth
rates and accountability of fiscal policy. The analysis indicates that
low and unbalanced economic growth remains a challenge for the
maintenance of financial stability and this problem cannot be
resolved just by a single supervision. In many countries bank assets
exceed their GDP by several times and large banks are still a matter
of concern, because of their systemic importance for individual
countries and the euro zone as a whole. The creation of the Single
Supervisory Mechanism and the Single Resolution Mechanism is a
response to the European crisis, which has particularly affected
peripheral countries and caused the associated loop between the
banking crisis and the sovereign debt crisis, but has also influenced
banks’ balance sheets in the core countries, as the result of crossborder
capital flows. The creation of the SSM and the SRM should
prevent the similar episodes to happen again and should also provide
a new opportunity for strengthening of economic and financial
systems of the peripheral countries. On the other hand, there is a
potential threat that future focus of the ECB, resolution mechanism
and other relevant institutions will be extremely oriented towards
large and significant banks (whereby one half of them operate in the
core and most important euro area countries), and therefore it remains
questionable to what extent will the common resolution funds will be used for rescue of less important institutions. Recent geopolitical
developments will be the optimal indicator to show whether the
previously established mechanisms are sufficient enough to maintain
the adequate financial stability in the euro area market.
Abstract: Different designs of attenuator systems have been
studied in this research; new analysis have been done on existed
designs considering fibers effect on air flow; it was comprehended
that, at fibers presence, there is an air flow which agglomerates fibers
as a negative effect. So some new representations have been designed
and CFD analysis has been done on them. Afterwards, one of these
representations selected as the most optimum and effective design
which is brought in this paper.
Abstract: Geographical routing protocol requires node physical
location information to make forwarding decision. Geographical
routing uses location service or position service to obtain the position
of a node. The geographical information is a geographic coordinates
or can be obtained through reference points on some fixed coordinate
system. Link can be formed between two nodes. Link lifetime plays a
crucial role in MANET. Link lifetime represent how long the link is
stable without any failure between the nodes. Link failure may occur
due to mobility and because of link failure energy of nodes can be
drained. Thus this paper proposes survey about link lifetime
prediction using geographical information.
Abstract: Mobile Ad hoc Network is a set of self-governing
nodes which communicate through wireless links. Dynamic topology
MANETs makes routing a challenging task. Various routing
protocols are there, but due to various fundamental characteristic
open medium, changing topology, distributed collaboration and
constrained capability, these protocols are tend to various types of
security attacks. Black hole is one among them. In this attack,
malicious node represents itself as having the shortest path to the
destination but that path not even exists. In this paper, we aim to
develop a routing protocol for detection and prevention of black hole
attack by modifying AODV routing protocol. This protocol is able to
detect and prevent the black hole attack. Simulation is done using
NS-2, which shows the improvement in network performance.
Abstract: In the present study, the properties of Al-Al2O3
nanocomposite hollow sphere structures were investigated. For this
reason, the Al-based nanocomposite hollow spheres with different
amounts of nano-alumina reinforcement (0-10wt %) and different
ratio of thickness to diameter (t/D: 0.06-0.3) were prepared via a
powder metallurgy method. Then, the effect of mentioned parameters
was studied on physical and quasi static mechanical properties of
their related prepared structures (open/closed cell) such as density,
hardness, strength, and energy absorption. It was found that, as the
t/D ratio increases the relative density, compressive strength and
energy absorption increase. The highest values of strength and energy
absorption were obtained from the specimen with 5 wt. % of
nanoparticle reinforcement, t/D of 0.3 (t=1 mm, D=400μm) as 22.88
MPa and 13.24 MJ/m3, respectively. The moderate specific strength
of prepared composites in the present study showed the good
consistency with the properties of others low carbon steel composite
with similar structure.
Abstract: Life cycle assessment is a technique to assess the
environmental aspects and potential impacts associated with a
product, process, or service, by compiling an inventory of relevant
energy and material inputs and environmental releases; evaluating the
potential environmental impacts associated with identified inputs and
releases; and interpreting the results to help you make a more
informed decision. In this paper, the life cycle assessment of
aluminum and beech wood as two commonly used materials in Egypt
for window frames are heading, highlighting their benefits and
weaknesses. Window frames of the two materials have been assessed
on the basis of their production, energy consumption and
environmental impacts. It has been found that the climate change of
the windows made of aluminum and beech wood window, for a
reference window (1.2m×1.2m), are 81.7 mPt and -52.5 mPt impacts
respectively. Among the most important results are: fossil fuel
consumption, potential contributions to the green building effect and
quantities of solid waste tend to be minor for wood products
compared to aluminum products; incineration of wood products can
cause higher impacts of acidification and eutrophication than
aluminum, whereas thermal energy can be recovered.
Abstract: This paper presents the results obtained by numerical
simulation using the software ANSYS CFX-CFD for the air
pollutants dispersion in the atmosphere coming from the evacuation
of combustion gases resulting from the fuel combustion in an electric
thermal power plant. The model uses the Navier-Stokes equation to
simulate the dispersion of pollutants in the atmosphere. It is
considered as important factors in elaboration of simulation the
atmospheric conditions (pressure, temperature, wind speed, wind
direction), the exhaust velocity of the combustion gases, chimney
height and the obstacles (buildings). Using the air quality monitoring
stations it is measured the concentrations of main pollutants (SO2,
NOx and PM). The pollutants were monitored over a period of 3
months, after that the average concentration are calculated, which is
used by the software. The concentrations are: 8.915 μg/m3 (NOx),
9.587 μg/m3 (SO2) and 42 μg/m3 (PM). A comparison of test data
with simulation results demonstrated that CFX was able to describe
the dispersion of the pollutant as well the concentration of this
pollutants in the atmosphere.
Abstract: The purpose of this study is the discrimination of 28
postmenopausal with osteoporotic femoral fractures from an agematched
control group of 28 women using texture analysis based on
fractals. Two pre-processing approaches are applied on radiographic
images; these techniques are compared to highlight the choice of the
pre-processing method. Furthermore, the values of the fractal
dimension are compared to those of the fractal signature in terms of
the classification of the two populations. In a second analysis, the
BMD measure at proximal femur was compared to the fractal
analysis, the latter, which is a non-invasive technique, allowed a
better discrimination; the results confirm that the fractal analysis of
texture on calcaneus radiographs is able to discriminate osteoporotic
patients with femoral fracture from controls. This discrimination was
efficient compared to that obtained by BMD alone. It was also
present in comparing subgroups with overlapping values of BMD.
Abstract: The use of titanium fluoride and iron fluoride
(TiF3/FeF3) catalysts in combination with polutetrafluoroethylene
(PTFE) in plain zinc- dialkyldithiophosphate (ZDDP) oil is important
for the study of engine tribocomponents and is increasingly a strategy
to improve the formation of tribofilm and provide low friction and
excellent wear protection in reduced phosphorus plain ZDDP oil. The
influence of surface roughness and the concentration of
TiF3/FeF3/PTFE were investigated using bearing steel samples
dipped in lubricant solution at 100°C for two different heating time
durations. This paper addresses the effects of water drop contact
angle using different surface; finishes after treating them with
different lubricant combination. The calculated water drop contact
angles were analyzed using Design of Experiment software (DOE)
and it was determined that a 0.05 μm Ra surface roughness would
provide an excellent TiF3/FeF3/PTFE coating for antiwear resistance
as reflected in the Scanning electron microscopy (SEM) images and
the tribological testing under extreme pressure conditions. Both
friction and wear performance depend greatly on the PTFE/and
catalysts in plain ZDDP oil with 0.05 % phosphorous and on the
surface finish of bearing steel. The friction and wear reducing effects,
which was observed in the tribological tests, indicated a better micro
lubrication effect of the 0.05 μm Ra surface roughness treated at
100°C for 24 hours when compared to the 0.1 μm Ra surface
roughness with the same treatment.
Abstract: Background: Muscle Energy Techniques (MET) have
been widely used by manual therapists over the past years, but still
limited research validated its use and there was limited evidence to
substantiate the theories used to explain its effects. Objective: To
investigate the effect of Muscle Energy Technique (MET) on anterior
pelvic tilt in patients with lumbar spondylosis. Design: Randomized
controlled trial. Subjects: Thirty patients with anterior pelvic tilt from
both sexes were involved, aged between 35 to 50 years old and they
were divided into MET and control groups with 15 patients in each.
Methods: All patients received 3sessions/week for 4 weeks where the
study group received MET, Ultrasound and Infrared, and the control
group received U.S and I.R only. Pelvic angle was measured by
palpation meter, pain severity by the visual analogue scale and
functional disabilities by the Oswestry disability index. Results: Both
groups showed significant improvement in all measured variables.
The MET group was significantly better than the control group in
pelvic angle, pain severity, and functional disability as p-value were
(0.001, 0.0001, 0.0001) respectively. Conclusion and implication: the
study group fulfilled greater improvement in all measured variables
than the control group which implies that application of MET in
combination with U.S and I.R were more effective in improving
pelvic tilting angle, pain severity and functional disabilities than
using electrotherapy only.
Abstract: To evaluate the vigor of wheat seeds and stress of
premature aging effects on germination percentage, root length and
shoot length of five wheat cultivars that include Vynak, Karkheh,
Chamran, Star and Kavir which underwent a period of zero, two,
three, four days in terms of premature aging with 41°C temperature
and 100% relative humidity. Seed germination percentage, root
length and shoot length in these conditions were measured. This
experiment was conducted as a factorial completely randomized
design with four replications in laboratory conditions. The results
showed that each of aging treatments used in this experiment can be
used to detect differences in vigor of wheat varieties. Wheat cultivars
illustrated significant differences in germination percentage, root
length and shoot length in terms of premature aging. The wheat
cultivars; Astar and Vynak had maximum germination percentage
and Karkheh, respectively Kavir and Chamran had lowest percentage
of seed germination. Reactions of root and shoot length of wheat
cultivars was also different. The results showed that the seeds with a
stronger vigor affected less in premature aging condition and the
difference between the percentage of seed germination under normal
conditions and stress was significant and the seeds with the weaker
vigor were more sensitive to the premature aging stress and the
premature aging had more severe negative impact on seed vigor.
Abstract: This paper presents results of the survey regarding the
awareness about HIV/AIDS among HIV-infected individuals. A
questionnaire covering various aspects of HIV-infection was
conducted among 110 HIV-infected individuals who attended the
G.A. Zaharyan Moscow Tuberculosis Clinic, Department for
treatment of TB patients with HIV. The questionnaire included
questions about modes of HIV transmission and preventive measures
against HIV/AIDS, as well as questions about age, gender, education
and employment status. The survey revealed that the respondents in
the whole had a good knowledge regarding modes of HIV
transmission and preventive measures against HIV/AIDS: about
83,6% male respondents and 85,7% female respondents gave an
accurate answers regarding the HIV-infection. However, the
overwhelming majority of the study participants, that is, 88,5% men
and 98% women, was quite ignorant about the risk of acquiring HIV
through saliva and toothbrush of HIV-infected individual. Though
that risk is rather insignificant, it is still biologically possible. And
this gap in knowledge needs to be filled. As the study showed another
point of concern was the fact, that despite the knowledge of HIV
transmission risk through unprotected sex about 40% percent of HIVpositive
men and 25% of HIV-positive women did not insist on using
condoms with their sexual partners. These findings indicate that there
are still some aspects about HIV-infection which needed to be
clarified and explained through more detailed and specific
educational programs.
Abstract: This study makes an integrated investigation on how
life satisfaction is associated with the Korean game users'
psychological variables (self-esteem, game and life self- efficacy),
social variables (bonding and bridging social capital), and
demographic variables (age, gender). The data used for the empirical
analysis came from a representative sample survey conducted in South
Korea. Results show that self-esteem and game efficacy were an
important antecedent to the degree of users’ life satisfaction. Both
bonding social capital and bridging social capital enhance the level of
the users’ life satisfaction. The importance of perspectives as well as
their implications for the game users and further associated research is
explored.
Abstract: Workflow scheduling is an important part of cloud
computing and based on different criteria it decides cost, execution
time, and performances. A cloud workflow system is a platform
service facilitating automation of distributed applications based on
new cloud infrastructure. An aspect which differentiates cloud
workflow system from others is market-oriented business model, an
innovation which challenges conventional workflow scheduling
strategies. Time and Cost optimization algorithm for scheduling
Hybrid Clouds (TCHC) algorithm decides which resource should be
chartered from public providers is combined with a new De-De
algorithm considering that every instance of single and multiple
workflows work without deadlocks. To offset this, two new concepts
- De-De Dodging Algorithm and Priority Based Decisive Algorithm -
combine with conventional deadlock avoidance issues by proposing
one algorithm that maximizes active (not just allocated) resource use
and reduces Makespan.
Abstract: Particle size distribution, the most important
characteristics of aerosols, is obtained through electrical
characterization techniques. The dynamics of charged nanoparticles
under the influence of electric field in Electrical Mobility
Spectrometer (EMS) reveals the size distribution of these particles.
The accuracy of this measurement is influenced by flow conditions,
geometry, electric field and particle charging process, therefore by
the transfer function (transfer matrix) of the instrument. In this work,
a wire-cylinder corona charger was designed and the combined fielddiffusion
charging process of injected poly-disperse aerosol particles
was numerically simulated as a prerequisite for the study of a
multichannel EMS. The result, a cloud of particles with no uniform
charge distribution, was introduced to the EMS. The flow pattern and
electric field in the EMS were simulated using Computational Fluid
Dynamics (CFD) to obtain particle trajectories in the device and
therefore to calculate the reported signal by each electrometer.
According to the output signals (resulted from bombardment of
particles and transferring their charges as currents), we proposed a
modification to the size of detecting rings (which are connected to
electrometers) in order to evaluate particle size distributions more
accurately. Based on the capability of the system to transfer
information contents about size distribution of the injected particles,
we proposed a benchmark for the assessment of optimality of the
design. This method applies the concept of Von Neumann entropy
and borrows the definition of entropy from information theory
(Shannon entropy) to measure optimality. Entropy, according to the
Shannon entropy, is the ''average amount of information contained in
an event, sample or character extracted from a data stream''.
Evaluating the responses (signals) which were obtained via various
configurations of detecting rings, the best configuration which gave
the best predictions about the size distributions of injected particles,
was the modified configuration. It was also the one that had the
maximum amount of entropy. A reasonable consistency was also
observed between the accuracy of the predictions and the entropy
content of each configuration. In this method, entropy is extracted
from the transfer matrix of the instrument for each configuration.
Ultimately, various clouds of particles were introduced to the
simulations and predicted size distributions were compared to the
exact size distributions.
Abstract: Spacer grid assembly supporting the nuclear fuel rods
is an important concern in the design of structural components of a
Pressurized Water Reactor (PWR). The spacer grid is composed by
springs and dimples which are formed from a strip sheet by means of
blanking and stamping processes. In this paper, the blanking process
and tooling parameters are evaluated by means of a 2D plane-strain
finite element model in order to evaluate the punch load and quality
of the sheared edges of Inconel 718 strips used for nuclear spacer
grids. A 3D finite element model is also proposed to predict the
tooling loads resulting from the stamping process of a preformed
Inconel 718 strip and to analyse the residual stress effects upon the
spring and dimple design geometries of a nuclear spacer grid.
Abstract: Nine Degrees of Freedom (9 DOF) systems are
already in development in many areas. In this paper, an integrated
pressure sensor is proposed that will make use of an already existing
monolithic 9 DOF inertial MEMS platform. Capacitive pressure
sensors can suffer from limited sensitivity for a given size of
membrane. This novel pressure sensor design increases the sensitivity
by over 5 times compared to a traditional array of square diaphragms
while still fitting within a 2 mm x 2 mm chip and maintaining a fixed
static capacitance. The improved design uses one large diaphragm
supported by pillars with fixed electrodes placed above the areas of
maximum deflection. The design optimization increases the
sensitivity from 0.22 fF/kPa to 1.16 fF/kPa. Temperature sensitivity
was also examined through simulation.