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ARPN Journal of Engineering and
Applied Sciences November 2018 | Vol. 13 No.
22 |
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Title: |
Numerical modeling and investigation of
hydrokinetic turbine with additional steering blade using CFD |
Author (s): |
Rudy Soenoko, Putu Hadi Setyarini and
Femiana Gapsari |
Abstract: |
The
rapid increase in global energy needs has generated a considerable
attention to the generation of energy from renewable energy sources.
Hydrokinetic turbines is a vertical axis type water turbine that is very
simple and appropriate for remote areas. A hydrokinetic turbine has a
good performance and is capable of producing considerable torque at high
water speeds. The activity in this study is to model a small
hydrokinetic turbine simulated with a CFD software, by varying
the position of the turbine runner in each 5°runner rotation so
as to obtain the pressure value between the two blades as an indicator
of the force magnitude occurring or generated. In a previous study a
vertical axis hydrokinetic turbine model was tested in the laboratory
compared to the results with a simulated test with CFD. The laboratory
test turbine performance result has a same or similar performance result
calculate from the CFD simulation. From the simulation results it is
seen that there are only two blades being pushed by the water flow. It
is suggested to add a steering blade on the turbine output area, in
order to increase the blade number to be pushed by the water flow rate.
By attaching a steering blade on the output part of the turbine, the
water prevents from leaving the turbine and deflected to push another
blade, resulting in more water-boosting blades. To ensure that this step
will produce a better result, the first step to do is simulating the
turbine with a steering blade. The results
obtained in every 5° runner position is that there is an increase
in water pressure between the two blades. This phenomenon shows that
there is an increase in the turbine performance. One of the simulation
results is, at a runner position
a = 20°, the water
pressure between blade two and blade three rises from 8.15e + 009 Pa in
the turbine without a steering blade, to 4.69e + 010 Pa in the turbine
with a steering blade. While the water pressure between blade five and
the blade six, that had a very low water pressure of 4.86e + 008 Pa,
rose to 2.30e + 010 Pa, after being given a steering blade. This shows
that the steering blade addition would give an additional water boost to
some blades. |
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Title: |
Mechanical and statistical analysis of
polypropylene composites derived from mixed clay-oil palm fruit
particles |
Author (s): |
A. Yaya, J. Daafuor, E. Bowen-Dodoo, V. D.
K. Domeh, E. Nyankson, B. Agyei-Tuffour, J. K. Efavi, V. A. Apalangya,
R. Owoare, B. Onwona-Agyeman and E. Annan |
Abstract: |
The
work presents a combined experimental and analytical study of the
influence of clay mixed with oil palm fruit and oil palm wood particles
as reinforcements in polypropylene composites. Sample morphology was
characterized via Scanning electron microscopy (SEM), and the mechanical
response determined via tensile and compressive testing. Statistical
modeling was employed to validate the experimental results. SEM images
show the particles are uniformly dispersed in the polypropylene matrix.
The polypropylene matrix tensile strength increases with increasing
amounts of reinforcement, with highest reinforcement seen for oil palm
wood particles of 1.51MPa. The implications of the results are discussed
to enhance the understanding of the clay-oil palm wood particulates as
potential reinforcement materials for structural and constructional
composites fabrication. |
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Title: |
Computer vision assistant for train
rolling stock examination (RSE) using level set models |
Author (s): |
Krishnamohan Kaja, Raghava Prasad and M.
V. D. Prasad |
Abstract: |
Rolling stock Examination (RSE) is automated with computer vision
sensors and programming models in development of a fully automated ARSE
model to assist human examiners. Four algorithms are being tested in
this work. We start with Chan Vese Level Sets (CV_LS); Morphological
Differential Gradient based Level Sets (MDG-LS), which are global
segmentation models. In the next part, we propose shape prior level sets
(SP_LS) and Invariance Shape Prior Level Sets (ISP_LS), which are local
segmentation methods. This work compares these proposed models in the
aspects of segmentation quality to correctly identify a bogie part and
to extract a defective part. Structural Similarity Index (SSIM) is the
measure to correctly identify a bogie part. Image Quality Index (IQI)
measures quality of segmented bogie part form all the 4 algorithms. Peak
signal to noise ratio (PSNR) tests the ability of the proposed
algorithms to identify defects in the bogie parts. ISP_LS is the best
local segmentation algorithm for both bogie part detection and defect
identification on rolling stock visual information at 4 different times
of the day. |
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Title: |
Influence of cutting parameters on tool
wear and surface roughness in machining SS304 using carbide and ceramic
inserts |
Author (s): |
Murugesan R. and Veeranaath V. |
Abstract: |
Aeronautical metals, such as titanium alloys and nickel centred blends,
display reduced cutting characteristics in the red to their outstanding
physical possessions which include low thermal conductivity and high
hardness at elevated temperatures. For these hard to turn metals, the
demand for High Speed Machining (HSM) is swelling in edict to achieve
great output and to save turning price. For uses it is vital to custom
firm and devoted turning setups and mechanisms with exact plans and
choices. The method to ensure constant stock for each operation and tool
is a prerequisite for HSM and acts as a basic criteria for high
productivity and process security. As machining speed is reliant on
machining and insert parameters, this type of machining should be well
defined as true machining overhead a certain level. So the rate at which
feeding is done is inversely proportional to the tool dimension if the
other parameters are unaltered. To recompense for a lesser span the
rotating speed must be improved to keep the equal machining speed. The
main area of concern insert hotness and insert attire depends on the
machining speed and spindle speed. Thus, the studies investigates the
relationship between insert hotness and inserts attire during turning of
SS304 and examine the deviation of surface finish and cutting forces for
two diverse kinds of machining inserts and also a model is developed for
authentication. |
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Title: |
Study heat diffusion of different
prosthetics during manufacturing process |
Author (s): |
Ali Sabri Abbas and Sarah Duraid Dawood |
Abstract: |
During the process of manufacturing the prosthesis sockets in the
lamination process, a chemical reaction occurs between the mixture of
materials used in the lamination process after being placed inside a
mold covered with layers of PVA, Perlon stockinet and with the existence
of materials to strengthen the socket or not. This chemical reaction
causes the emission of heat from within the sample. The emission
continues until the sample is cooled by natural convection, which lasts
for 30 minutes or less depending on the amount of hardener material used
in the laminating process. The current work focused on observing the
thermal distribution occurring on the surface of the hot sample during
the cooling period, in order to see areas with high thermal
concentration from other regions. Then put the thermal gradient map for
the whole sample that helps to understand thermal stress which is used
to evaluate the stresses induced by some thermal load, which is in the
form of thermal images that's taken by using a thermal camera known as
FLIR i7, which shows thermal distribution on each side of the sample.
For more results, three molds were made for different levels of
amputation (above knee amputation (AK), below knee amputation (BK) and
Syme amputation. Then use the thermal camera to obtain thermal
distribution images for each sample. |
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Title: |
Investigations of optical, electrical and
thermal properties of piezo PMMA/PVDF membrane as electrical and
advanced energy saving materials |
Author (s): |
Asra Ali Hussein, Ammar Emad Al-kawaz and
Zahraa Najah Salman |
Abstract: |
Present work is aimed at developing electrical and energy storage
component based on PMMA/PVDF blend. The film of PMMA/PVDF was prepared
using solution casting method with a verity weight percentage of PVDF.
Physical properties such as (absorption coefficient, extinction
coefficient, refractive index and real and imaginary dielectric
constants) have been studied. Some expository strategies, for example,
FTIR spectroscopy, differential scanning calorimetry (DSC), were used to
assess the compatibility of these two polymers. Results show that the
(absorption coefficient, extinction coefficient, refractive index and
real and imaginary dielectric constants are increased by increasing PVDF
content. As well as the absorbance increased with increasing the amount
of PVDF while transmittance decrease. Moreover, the electrical
conductivity has been increased with increasing PVDF content. |
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Title: |
Spatiotemporal monitoring of methane over
Iraq during 2003-2015: Retrieved from atmospheric infrared sounder
(AIRS) |
Author (s): |
Faten G. Abed, Ali M. Al-Salihi and Jasim
M. Rajab |
Abstract: |
Observations of methane (CH4) retrieved from Atmospheric Infrared
Sounder (AIRS) on the EOS/Aqua platform from 2003-2015 show a strong,
plume-like enhancement of CH4 over central and southern-east parts of
Iraq during August - September, with the maximum occurring in early
September and minimum in March - May over western, southwest, and
north-east regions. The percentage change differences results shows the
highest differences occurred over the central and southern regions and
the smallest differences occurred over the western and southwest
regions. To better validate the retrieved data from AIRS three stations
at different locations were chosen for trend analysis. The mean and
standard deviation in Mosul, Baghdad and Basrah was (3.610 ± 0.042,
3.818 ± 0.048, 3.824 ± 0.055) x1019 Mole.Cm-2 respectively for monthly
long term trend analysis. Annual trend analysis shows positive trends,
and ranged between (0.0083 and 0.0097) Mole.Cm-2.y-1 for Mosul and
Basrah, respectively. Monthly trend analysis have positive trends
(0.0092) Mole.Cm-2.y-1 for Mosul and (0.0107) Mole.Cm-2.y-1 for Baghdad
and Basrah. The annual linear growth rate were (2%) for Mosul, and (3%)
for Baghdad and Basrah, and monthly linear growth rates were (5%) for
Mosul and Baghdad, and (6%) for Basrah. Further daily long term trend
shows significant linear increase of (3.7 %) caused a trend of (0.0107 ×
1019) Mole.Cm-2.y-1 in Baghdad. The standard deviation of variation in
daily average CH4 as a percentage deviation from the mean for the
departure from the mean was (1.62%), (0.06×1019 Mole.Cm-2). And the day
to day variation with a clear seasonal change shows standard deviation
of enter sequential changes was (0.053 × 1019) Mole.Cm-2. These results
indicate that Satellite observations efficiently show the temporal
variations of the CH4 values over different regions. |
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Title: |
Time delay model for a predator and two
species with mutualism interaction |
Author (s): |
Y. Suresh Kumar, N. Seshagiri Rao and B.
V. Appa Rao |
Abstract: |
The
present paper focus on to know the dynamical behavior of a three species
system made up of a predator together with mutualism interaction between
two species in the limited resources, where as the predator is depending
on both the mutual species. In this model the time delay is proposed to
the predator and the first mutual species to recognize the
sustainability of the system in long run. Local asymptotic stability of
diverse existing positive equilibrium solutions is investigated to
understand the dynamics of the system. Further the global stability is
established using appropriate Lyapunov functional at positive interior
equilibrium solution. Finally numerical simulation is execute to examine
the delay impact that can lead to transformation from stable to unstable
or unstable to stable culminate Hopf bifurcation. |
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Title: |
Face recognition system based-on
imperialist competitive algorithm and neural network (ICANN) |
Author (s): |
Hassan Jassim Motlak, Ehab Abdul Razzaq
Hussein and Ali Shaban Hassony |
Abstract: |
This
paper presents smart security system based-on Imperialist Competitive
Algorithm Neural Network (ICANN). The proposed system consists from
high-resolution camera, motion sensors, and control system. The Camera
installed up side of security main gate, park's entry, and office's gate
connected with motion sensors. The comparison process start in case
person detected by motion sensor. The comparison process between saved
image of authorized person with image of suspected person take it by
(USB full HD camera), if there is a matching between them, the decision
of control system will open the gate if there is no matching the gate
stay in closed case. In addition to that, all gates controlled by
central control office to send alarm in suspected cases. Principal
Component Analysis (PCA) used for features extraction and ICANN for
image detection and all software recognition process is based-on (Math
Lab). The results obtained from the simulation system shows faster more
accurate than other traditional methods. Moreover, the results show
efficient and reliable security system with accuracy around 96%.
Practical system shows excellent agreement with that obtained by
simulation results. |
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Title: |
Shock absorber and spring contribution
reduces vertical vehicle loads that burden the road structure |
Author (s): |
Simon Ka’ka, Syukri Himran, Ilyas Renreng
and Onny Sutresman |
Abstract: |
Driving
comfort for riders and passengers is a key target to be achieved.
Fluctuations in vehicle loads, bumps, perforated surfaces, and other
road damage will greatly affect the vehicle suspension working system.
This study aims to (1)examine more about the effect of vertical dynamic
load of vehicles and changes in dimensional barriers on the road surface
in its path.(2) obtain the amount of vibration and load reduced by the
working of the spring and shock absorber. Load changes arising from the
number of non-permanent passengers always burden the vehicle suspension
in a fluctuating manner. Experimentally these load fluctuations are
replaced by pneumatic actuator forces of varying magnitude based on the
regulatory pressure of the regulator. The deviations generated by the
varying load work are measured by placing a proximity sensor along the
spring movement. The vertical dynamic load transformation up to the road
surface is measured using a "Load cell" mounted under the wheels of the
vehicle. Characteristics of vertical dynamic vibration occurring due to
several dimensional barriers, U (cm) obtained using mathematical
modeling method with 2 DOF suspension system transfer function. The
results showed a condition on the body and wheels of vehicles
experienced a brief overshot for 0.14 seconds with deviation of 0.178 m.
From the graph shows that the rate of deviation that occurs is large
enough that Y2d = 1.03 m / s caused by a sudden shock that occurred on
the wheels of the vehicle. This condition does not last long that is
only duration t = 0.22 s, because of the reaction of the spring and
shock absorber that can dampen the vibration not less than 25% to the
vibration caused by the vertical load of the body and the axle of the
vehicle. |
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Title: |
Optimal load shedding under contingency
conditions using voltage stability index for real-time applications in
power systems |
Author (s): |
Raja Masood Larik, Mohd. Wazir Mustafa,
Manoj Kumar Panjwani and Kashif Naseer Qureshi |
Abstract: |
Power
systems operating under stress may approach a collapse point resulting
in blackouts. To avoid this problem corrective measures such as load
shedding are required. Conventional techniques are fail to provide
optimal load shed. This paper focuses on optimal load shed as well as
enhancing the system voltage profile using a hybrid optimization
algorithm based on the well-known Genetic Algorithm (GA) and Particle
Swarm Optimization (PSO). GA has traditionally been known for its
accuracy while the PSO algorithm is popular for its fast convergence
time. GA algorithms require longer convergence times due to the complex
nature of their cost functions; therefore, in this work PSO is applied
to the GA construction to solve this problem. This result in a fast and
accurate algorithm named GAPSO. This paper focuses on optimal load shed
by using hybrid optimization termed as GAPSO. The proposed algorithm is
utilized to minimize the total amount of load shed on the weak buses.
Weak buses are identified using the Fast Voltage Stability Index. The
performance of the proposed technique was assessed by simulations in
MATLAB/SIMULINK under the IEEE-30 and IEEE-57 bus meshed networks. The
proposed technique was also compared to the GA and PSO algorithms
individually and it outperform both in terms of optimal load shed which
is comparable to GA while a convergence time is comparable to PSO.
Proposed technique is not only robust against system failures but is
also efficient enough for real time applications. |
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Title: |
Soret effect on unsteady MHD free
convective two immiscible fluid flow through a horizontal channel with
heat and mass transfer |
Author (s): |
L. Sivakami and A. Govindarajan |
Abstract: |
Unsteady MHD Free convective two immiscible fluid flow through a
Horizontal channel with Heat and mass transfer have been studied in this
paper. The effect of Soret is also taken into account. The equations are
solved analytically and numerically with the appropriate boundary
conditions for each fluid and the solutions have been studied. The
governing equations of the flow were transformed into ordinary
differential equations by a regular perturbation method and the
expression for the velocity; temperature and concentration for each
fluid flow were obtained. The effects of various parameters like Grashof
numbers for heat and mass transfer, Prandtl number, Viscosity ratio,
Conductivity ratio, Radiative parameter, Soret number etc. on the
velocity, temperature and concentration fields have been presented
graphically. |
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Title: |
Triboelectrification of sliding objects
against floor in hospitals |
Author (s): |
El-Sherbiny Y. M., Ali A. S. and Ali W. Y. |
Abstract: |
The
increased use of polymeric materials in hospital floorings raised the
issue of electrostatic charges and its implications. Electrostatic
charges generated from friction of engineering materials show a negative
effect on their applications particularly in health related issues.
Electrostatic charges accumulating on human skin are dangerous and cause
serious health problems. The present work investigates the electrostatic
generated charge from dry and wet rubbing of disposable- Anti-Skid
polypropylene shoe covers “Non Slip Medical”, and rubber against
polymeric flooring materials. Decreasing normal load in dry rubbing of
polypropylene against epoxy floor decreased measured friction. Friction
values at light loads maintained good adhesion of the sliding objects
against floor µ = 0.5. It was enough for safe use at dry rubbing
condition. Sliding of hospital foot wear on dry floor generated higher
electrostatic charge. Wet rubbing, however, generated charge values
higher than these measured for repeated alternate contact and
separation. Water wetted contacts resulted in lower values of friction
and electrostatic charge relative to those obtained in dry contact
situations. Water molecules in wet contacts facilitated the conduction
of generated electrostatic charges at the contact interfaces, thereby
resulted in lower measurements for wet contacts. Accordingly it was
recommended to look for new materials and coatings maintaining values µ
= 0.5 to prevent slip and fall, with lower electrostatic charges. |
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Title: |
Performance analysis of different array
configurations for smart antenna applications using firefly algorithm |
Author (s): |
K. Sridevi and A. Jhansi Rani |
Abstract: |
Voluminous studies have already been conducted on smart antennas. Mostly
these studies dedicated to Uniform linear array, Rectangular array and
circular array configurations. This paper aims at the investigation of
the beam forming capabilities of uniform hexagonal array (UHA) and
planar uniform hexagonal array (PUHA) configurations as compared to
circular array by controlling amplitude excitation only using firefly
algorithm. Results are compared with that of Particle swarm optimization
technique. Comparisons are made in the context of adaptive beam forming
capabilities of the three array configurations. |
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Title: |
Cnidoscolus aconitifolius model in batik
pattern generation by using random walk |
Author (s): |
Purba Daru Kusuma |
Abstract: |
This
paper discusses the development of Cnidoscolus aconitifolius leaves
model as batik pattern. Cnidoscolus aconitifolius is a papaya like tree
that is popular in Indonesia. Even this plant leaf are similar to the
papaya leaf, basically this plant is different from the papaya family.
In the other side, papaya leaf pattern has been used as a plant based
traditional batik pattern because its specific finger like leaf
morphology. So, developing other finger like leaf batik pattern by using
computational technology is challenging. In this research, besides
developing the leaf model, the plant branching model is developed too.
The reason is to make difference between the Cnidoscolus aconitifolius
with the common papaya tree that does not have branching
characteristics. This model is developed by using random walk as its
basis method. After the basic model is developed, this model then is
used to generate batik pattern computationally in web based batik
pattern generation application. Based on the tests, there are several
research findings. The inter petiole distance has negative correlation
with the number of generated leaves. The lobe angle deviation has
positive correlation with the leaf circular width. The sting hair step
angle deviation has positive correlation with the lobe width. Small
value of the sting hair step angle deviation can produce Picuda like
leaf. Medium value of the sting hair step angle deviation can produce
Estrella like leaf. |
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Title: |
Low energy consumption rate in home
sensors using prime nodes |
Author (s): |
Hesham Abusaimeh |
Abstract: |
Many
of conventional home and industrial automation systems have
substantially spurred the appearance of the embedded devices with
wireless sensors in order to execute their functionality in the wireless
sensor networks or to build inter-device wireless communication. To
facilitate the adaptation of wireless sensor networks (WSN) to
industrial applications, concerns about problems of battery power and
energy resources must be addressed to fulfill real time requirements. In
fact, the network has many wireless nodes that depend on their batteries
as power supply to stay connected and operate well. The main reason of
spending the nodes power is the data transmission and reception
operations via the wireless signals. Many researches have been conducted
to enhance the remaining energy of the home devices that are based on
sensors and to increase these home sensors lifetime. A novel method has
been presented in this paper to optimize consuming power in these home
sensors. This issue can be done by, enhancing the functionality of some
home devices by making them as central nodes (prime nodes) for the other
home sensors by reducing their consumption rate. This will lead to
eliminate some transactions of transmissions and receptions of the home
sensors. Hence, powerful home sensors are employed to have the
capability to live longer and have more power supply to be used in
various home application. Large scale of home sensors are used in the
simulation conducted in this research in order to make it accurate. The
simulation results clarify the efficiency of the proposed mechanism in
term of low power consumption rate of the home devices with the
availability of the prime home sensor nodes that have the capability to
live longer. |
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Title: |
Effect of fluid gap cell size in a suction
valve on performance of a linear compressor |
Author (s): |
Y. N. Jang and Y. L. Lee |
Abstract: |
Fluid
gap cell is used for CFD analysis of compressor valve. The effect of the
fluid gap cell on compressor performance prediction is still
insufficient. Therefore, in this study, the performance change in the
compressor was investigated by varying the fluid gap cell size from 100
µm to 10 µm. As the fluid gap cell size decreases, the maximum valve
lift increases and the second valve opening lift becomes steeper. Also,
the smaller the fluid gap cell size, the more accurately the valve flow
rate is predicted when the valve is at closing. However, it has little
effect on the PV diagram. In summary, the fluid gap cell size affects
valve lift and valve suction flow rate changes but has little effect on
CW, CC, and EER. Therefore, a 100um fluid gap cell can be used if you
are only interested in overall compressor performance. Otherwise, it
would be better to use a fluid gap cell of 25 µm or below. |
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Title: |
A simplified method for energizing the
solenoid coil based on electromagnetic relays |
Author (s): |
Munaf Fathi Badr |
Abstract: |
The
purpose of this work is to present a simplified, relatively inexpensive
and rapid response electrical control system which has been used to
energize the solenoid coil. The suggested approach involves using
electromagnetic relays as main control elements in the control model to
meet the requirement of specified proposed control system of the
solenoid. The selected solenoid operated in two positions and the
control circuit can be easily applied to actuate the solenoid coil in
two conduction states either ON or OFF. The laboratory work has been
taken place to conduct the theoretical calculations with practical
implementation of the solenoid control circuit in conjugated with
computer simulations using the required software package such as Matlab
were also done to compare the theoretical and practical results. The
obtained results showed that the ability of employing the
electromagnetic relays in the proposed control circuit of solenoid with
fast response and high reliability. |
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Title: |
Piezoelectric ceramic for energy
harvesting system: A review |
Author (s): |
N. X. Yan, A. A. Basari, K. S. Leong, N.
A. A. Nawir and S. Hashimoto |
Abstract: |
Nowadays, piezoelectric energy harvesting technology has been studied
and developed significantly by a lot of researchers. Energy harvesting
is a process that an ambient waste energy can be collected and conserved
or stored for useful purposes. Piezoelectric transducer is one of the
devices that can be used for vibration energy harvesting system. It has
a high ability of energy conversion to convert mechanical vibration into
electrical energy compared to others. In this paper, a comprehensive
review on the piezoelectric energy harvesting system is discussed and
presented, including the principles of the piezoelectricity, mechanical
configurations of the piezoelectric and techniques employed to the
piezoelectric energy harvester. The integral ideas and performance of
the reported piezoelectric energy harvester will be reviewed in this
paper as well. |
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Title: |
Some ways to reduce the dynamic loads of
agricultural machine-tractor aggregates |
Author (s): |
A. S. Ovchinnikov, N. G. Kuznetsov, D. D.
Nekhoroshev, D. S. Gapich, D. A. Nekhoroshev, S. D. Fomin, B. P.
Zagorodskikh, V. M. Slavutsky, M. N. Shaprov, A. I. Ryadnov and A. N.
Tseplyaev |
Abstract: |
One
of the ways to increase the efficiency of the transmission system of an
agricultural tractor traction concept is to introduce a clutch coupling
with a pneumatic-hydraulic elastic element into the transmission.
Installation of an elastic element in the form of a pneumo-hydraulic
accumulator (PHA) in the clutch is associated with the need to implement
a calculated loading regime for any technological operation on the same
engine operating mode, as well as the need to mitigate impact phenomena.
In this case, it should be possible to change its stiffness depending on
the technological operation being performed. This can be done by
justifying the working area of the elastic characteristics of the PHA
under operating conditions. It is determined by the possible range of
variation (oscillation) of the tractor pulling force. It is within its
limits that the elastic properties of the shaft line must be manifested,
which ensure the stabilization of the loading regime. Numerous studies
machine-tractor aggregates show that the maximum deviations of the
pulling force P from its average value are under extreme conditions up
to 35%. |
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Title: |
Robust face recognition for blurred images
with iterative graph based restoration using linear collaborative
discriminant regression classification (LCDRC) |
Author (s): |
Hema Sree P., Laxminarayana P. and Subba
Rao K. |
Abstract: |
Face
Recognition using images obtained from the unconstrained environment is
the challenge, yet to be resolved. This situation is due to cluttered
background and poor lighting conditions or illumination. Capturing
images from a long distance, atmospheric turbulence, out of focal length
and camera in motion are also the reasons behind the drastic decline in
the performance of face recognition. A novel three-step formula has been
proposed in this paper to address the issues from existing methodologies
and provide the consistent accuracy in final face recognition. First and
foremost, the query image of a face is thoroughly analyzed to know the
blur presence and its type. Later, the model images are also blurred to
the same extent as of query image and face recognition is done using
deblurring both model and query images by Iterative Graph based image
restoration technique. The accuracy of the face recognition using the
proposed algorithm is consistent under different levels and types of
blurring. The performance of the proposed method (for blurring and
deblurring the models) is validated for different classification
algorithms namely Collaborative Representation Classification (CRC),
Relaxed Collaborative Representation (RCR) and Linear Collaborative
Discriminant Regression Classification (LCDRC). LCDRC outperformed the
existing peers in accuracy and robustness. The best recognition rate of
96.25 % is obtained for blur face images using this proposed method. |
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Title: |
Study of performance of heat exchanger
using water and sand for zinc roof cooling with automatic water spraying |
Author (s): |
Jefrey I. Kindangen and Markus K. Umboh |
Abstract: |
The
purpose of this study is to compare the performance of a heat exchanger
using water and sand as a cooling medium to cool the surface of the zinc
roof by spraying water automatically. The heat exchanger consists of
cooling coil made of 3/4” diameter copper formed the sinusoidal curve
and planted 10 cm of depth in 1 x 1 x 0.2 m acrylic container filled
with water or sand. Water is automatically sprayed onto the surface of
the zinc roof and then flowed into a heat exchanger. Comparing the
performance of a heat exchanger using water and using sand shows that
they basically have a performance that can lower the water temperature
used for spraying onto zinc roofing surfaces. The water-to-water heat
exchanger that uses water as a cooling medium is more effective in the
morning until noon, while the water-to-sand heat exchanger that uses
sand as a cooling medium will be more effective during the day until
late afternoon. In general, the water-to-water heat exchanger is more
able to lower water temperatures compared to the water-to-sand heat
exchanger. This system essentially demonstrates its usefulness and
capacity as one of the passive cooling strategies that can lower the
zinc roof surface temperature which in turn lowers the indoor air
temperature. |
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Title: |
A corpus for Amazigh transcribed to Latin
OCR systems’ evaluation |
Author (s): |
Khadija E. L. Gajoui, Fadoua Ataa Allah
and Mohammed Oumsis |
Abstract: |
Corpora, initially created as resources for linguistic research, are
attracting more and more the attention of machine learning researchers
who are examining the potential of these corpora for training/ testing
optical character recognition (OCR) systems. Following the last logic,
this paper is concerned with research on OCR of printed historical and
recent document written in Amazigh transcribed to Latin. It focuses,
especially, on building a representative corpus dedicated to this
language. In this paper, we describe the construction procedure of this
corpus in tree levels, which are: line, word and character. Then we
conduct a comparative evaluation of the corpus using an OCR system based
on Long Short Term Memory approach. The comparison of the corpus is
depending on the recognition rates and convergence in term of iteration
number. Evaluation shows that the corpus level line gives the best
result compared to the other levels with an error rate of 10.3%. |
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Title: |
Laser-field technology of hardening |
Author (s): |
Bashmakov D. A. and Galiakbarov A. T. |
Abstract: |
Modern methods of materials laser processing are being actively
introduced into production. However, their wide application in
engineering is hampered by the high energy intensity of the processes
and the unexplored of complex fast processes of such processing
technologies. This work is devoted to hybrid laser technologies for
material processing, in particular laser-field hardening of metals. A
theoretical study of the laser interaction with a metal is carried out,
it is shown that the reflection coefficient of laser radiation and the
depth of its penetration depend on the electrical conductivity of the
skin layer. The main interrelations between the quality parameters of
the treated layer and the parameters of the laser-field technological
complex are revealed. Investigations on laser hardening in the
electrostatic field of steels, widely used in engineering, have been
carried out (Steel 10, 45, 65G). It is shown, that the superposition of
the electrostatic field on the treatment zone leads to an increase in
the depth and hardness of the quenched layer due to the directed motion
of electrons in metals. |
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Title: |
Evaluation of the performance of a hybrid
MIMO Beamforming system for the cancellation of interference |
Author (s): |
Martin D. Bravo Obando, Leonardo Motta
Vargas and Xiomara A. Tejada Vera |
Abstract: |
In
this paper the performance of a hybrid MIMO scheme is evaluated with
Beamforming, where the hybrid MIMO scheme presents a diversity gain and
multiplexing at the same time, and it includes the beamforming with the
purpose of strengthening more the transmission. The results obtained
show that the hybrid MIMO structure with beamforming improves on average
5.4dB the quality of the information received, with schemes of
modulation 4QAM, 16QAM and 64QAM. |
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Title: |
Modified Nonlinear Predictive PI
controller for a conical tank level process |
Author (s): |
T. Bhuvanendhiran, S. Abraham Lincon and
I. Thirunavukkarasu |
Abstract: |
A
Modified Nonlinear Predictive PI (MNPPI) control technique is a
combination of two well-known control strategies of a Model Predictive
Control (MPC) and Proportional Integral Derivative (PID) controller.
This combination provides better control performance when compared to
MPC and PID controllers. In this paper, the Modified Nonlinear
Predictive PI control strategy is designed, implemented to a nonlinear
process and performance indices such as IAE, ISE, IATE, settling time,
rise time, over shoot are compared to other controller. It’s observed
that, the designed controller shows lesser rise time and settling time
along with ensured stability. |
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Title: |
Simplified model for design RCC box
culverts by STAAD.Pro |
Author (s): |
Abdul Kareem M. B. Al-Shammaa |
Abstract: |
Reinforced concrete box culvert consists of top slab, bottom slab and
two vertical side walls built monolithically which form a closed hollow
rectangular or square single cell or multiple cells. Culverts are
required to be used under earth embankment to construct and pass roads
or railways at the moment for crossing of water from both sides of earth
embankment. Current of great rivers and their tributaries in my country
have encouraged me to go ahead to find simplified method for design box
culvert. This research focuses on analysis and design of single cell by
software “STAAD.Pro” on a segment in one meter length from culvert
barrel to produce a plane structure like instead of space structure. The
structure is subjected to various types of loads and supported by a bed
of springs instead of soil interaction according to Winkler's modeling.
The author believes that he is able to create a method which is quick,
accurate and optimal solution for design RCC box culvert. This paper was
carried out using ACI-code 2011 with SI units. |
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Title: |
Khmer handwritten text recognition with
Convolution Neural Networks |
Author (s): |
Bayram Annanurov and Norliza Mohd. Noor |
Abstract: |
This
paper presents a pilot study on Khmer handwritten symbols recognition
using Convolutional Neural Networks (CNNs). The motivation for this
study is to develop a recognition system for digitizing large corpora of
Khmer handwritten documents. Image data consists of six handwriting
sample sets, each of which consists of 33 consonants (root radicals) and
17 vowels, total of 561 syllables. A CNN-based model was trained for
offline recognition of root radicals where one CNN was trained for
recognition of a particular consonant. All 33 networks have been
combined into an assembly. The recognition results are compared against
artificial neural network (ANN)-based classifier with full feature set
and ANN -based classifier with dimensionality reduction. Feature
correlation two-dimensional Fourier transformation (FT2D) and Gabor
filters are used for dimensionality reduction. Recognition rate of Khmer
handwriting (alphasyllabary system) is increased to 94.85% with
Convolutional Neural Networks (CNN). |
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Title: |
Optimization of SPI controller for
hardware embedded systems using finite state machines |
Author (s): |
Edwar Jacinto G., Fernando Martinez S. and
Holman Montiel A. |
Abstract: |
This
article shows the design and implementation of a finite state machine
that describes the operation of the SPI protocol in a standard way,
which is a serial protocol used for transfers with peripherals with low
/ medium bandwidth, all the technical detail of a specific application,
and emphasis is placed on making a description with a low level of
abstraction to reduce the amount of hardware resource used, arriving at
a general-purpose IP CORE type solution. The state machine controls the
sequence of the communication that comply with the protocol. By having a
design of low complexity, it achieves to be easily adaptable for a
number of plates (shields) that proliferate in a significant number of
academic and commercial applications. |
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Title: |
Inorganic and organic N variations in
Setiu River Basin, Malaysia |
Author (s): |
Suhaimi Suratman, Yet Yin Hee and
Norhayati Mohd. Tahir |
Abstract: |
The
main objective of the present study was to evaluate the variations of
inorganic and organic nitrogen (N)-based nutrients based on seasonal
changes in the Setiu River Basin, situated at the southern part of the
South China Sea (Malaysia). In addition, fractionation of the dissolved
organic N (DON) was also determined. Results showed an increase of these
nutrients was observed from the upstream to the downstream stations due
to the impact of anthropogenic activities. It was found that during the
wet season, runoff from the land increased the nutrient concentrations
in the water column. High molecular weight DON is the main fraction of
DON, constituting more than 60% of the total DON. |
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Title: |
MHD natural convection flow past a moving
vertical plate with ramped temperature |
Author (s): |
Siva Reddy Sheri, Vijaya Bhaskar and Anjan
Kumar Suram |
Abstract: |
An
investigation has been carried out numerically to study MHD natural
convection flow of an incompressible, electrically conducting, radiative
and heat absorbing fluid past a moving vertical plate with ramped
temperature. Solutions of the governing partial differential equations
for primary velocity, secondary velocity and temperature are obtained by
using Finite element method. The influence of Magnetic parameter ,
thermal Grashof number , Hall current parameter , viscous dissipation
and thermal radiation parameter on primary velocity, secondary velocity
and temperature are computed numerically and represented graphically.
Effect of pertinent flow parameters on shear stress and rate of heat
transfer are displayed in a tabular form. Various comparisons with
previously published work are performed and the results are found to be
in excellent agreement. |
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Title: |
Periodic time spread pulse signals with
perfect autocorrelation |
Author (s): |
A. V. Titov and G. J. Kazmierczak |
Abstract: |
This
paper considers periodic single pulse signals (PSPS) of pulse duration T
and time repetition NT, where N (N>1) are positive integers. This paper
examines a new previously unknown property of these signals that have
perfect periodic autocorrelation on the interval NT. It is shown that
PSPS can be represented as the linear composition of several orthogonal
periodic pulse signals with zero cross correlation, and once represented
as such, these signals can be transformed into periodic time spread
pulse signals where the pulses are spread over the entire interval NT.
These transformed signals have the same energy and autocorrelation
properties as the corresponding original PSPS. The results of this study
advance the theory of pulse signals and can be applied to any electronic
periodic pulse signal system including radar, radio navigation,
communication and telemetric systems. |
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Title: |
Effects of radiation and thermal diffusion
on MHD heat transfer flow of a dusty viscoelastic fluid between two
moving parallel plates |
Author (s): |
B. Mallikarjuna Reddy, D. Chenna Kesavaiah
and G. V. Ramana Reddy |
Abstract: |
An
anticipated outcome of present analysis is effects of radiation and
thermal diffusion on MHD heat transfer flow of dusty viscous,
incompressible, electrically conducting fluid between two parallel
plates with constant suction on the upper plate and constant injection
on the lower plate, first order chemical reaction, variable temperature
and uniform mass diffusion taking into an account. The governing partial
differential equations which describe for motion of the problem change
into dimensionless equations and solved by using perturbation technique.
The various analytical quantities for the velocity profiles (for dusty
fluid and dust particles), temperature profiles, concentration profiles
and skin friction coefficient are examine and depict graphically in
detail. |
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Title: |
Real time particulate matter concentration
measurement using laser scattering |
Author (s): |
Chee F. P., Angelo S. F., Kiu S. L.,
Justin S. and Jackson C. H. W. |
Abstract: |
Particulate Matter (PM) is the sum of all solid and liquid particles
suspended in air. It can be classified into PM1.0, PM2.5, and PM10 based
on the size of the particles. Smaller particles are extremely hazardous
as they can penetrate into our respiratory system causing adverse health
effects. In this paper, a real time, portable and cost effective PM
sensor system is designed for the monitoring of air particulate matter
concentration. To achieve the objectives, a particulate matter
monitoring device was constructed using PM Sensor SEN0177, Temperature
and Humidity Sensor DHT11, Arduino Mega, DS1307 RTC and TFT LCD for data
visualization. The system can simultaneously measure the concentration
of PM at varying sizes. Besides, it is also equipped to measure RH and
ambient air temperature. Built in real time clock and data logging
system was also included as added function. The system employs a real
time monitoring system for particulate matter using laser scattering
technique and interfaced using MIE theory algorithm. The completed
prototype was tested with TE 600 PM10 Air Sampler and General consumer
for accuracy test. The system offers particulate matter detection based
on laser scattering principle with a considerable accuracy of 87.7% in
comparison when being compared with the TE6001 PM10 air sampler. The
main advantage of this system is its ability to provide real time
monitoring to obtain in situ data on the PM concentration together with
RH and temperature readings which are crucial factors in the air quality
monitoring. |
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Title: |
Performance assessment of BIM managers
using Multi-Source feedback method - A pilot study |
Author (s): |
Faiq M. S. Al-Zwainy |
Abstract: |
In
order to assure an objective assessment of BIM managers' performance,
standards to assess the skills and competence of construction
professionals in using Building Information Modeling (BIM) got to be
set. This paper aims at creating some rating criteria to assess the
performance of BIM managers in Iraq through a pilot study. A new
technique of performance assessment known as Multi-Source or 360°
feedback method was employed for this purpose aided by a questionnaire
form specially designed to match the technique and the purpose. The
Center of Engineering Consultancy at the Ministry of Industry and
Minerals was chosen to implement the pilot study for it is the first
firm that initiates the application of BIM in Iraq. It was found that
performance assessment of the BIM managers is quite different among
constituents (bosses, peers, staff, contractors and clients) especially
when compared to the BIM managers' self-assessment which was always
over-estimated. The highest degree of assessment was found to be (3.975)
out of (5) degrees for the best BIM manager. This indicates the
necessity of adopting such objective approach in the organization
culture instead of personal judgment of bosses. As a result, the use of
Multi-Source feedback method in assessing the performance of BIM
managers proved to be successful and can be used in other firms in the
Iraqi construction sector. |
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Title: |
Investigation of mechanical properties of
PMMA composite reinforced with different types of natural powders |
Author (s): |
Sihama Issa Salih, Jawad Kadhim Oleiwi and
Arkan Saad Mohamed |
Abstract: |
Poly
Methyl Methacrylate were widely accepted material in dental and medical
field due to the excellent biocompatibility and easy fabrication,
however exhibit inferior mechanical properties. In current research, two
groups of PMMA nano composites samples were fabricated by using hand
lay-up method at laboratory temperature. used for manufacturing of the
maxillary complete or partial denture base. These samples consist of
poly methyl methacrylate (PMMA) resin as a matrix material, was
strengthen by two different natural powder in nanometer size
(pomegranate peels (PPP) and seed powder of dates Ajwa (SPDA)) in
individually form, with selected weight fraction ratio (0, 0.4, 0.8, 1.2
& 1.6 wt. %). Some mechanical properties and analytical physical
properties (FTIR, SEM) were investigated. The result showed a
considerably improvement in the values of these properties for both
groups of bio composite specimens comparing with neat PMMA. All bio
composite specimens reinforced with pomegranate peels powder in
nanometer size showed the highest properties as compared with the bio
composite specimens strengthened by nano seed powder of dates ajwa. The
highest value of flexural strength, flexural modulus, max. shear stress,
impact strength and fracture toughness were 114MPa, 5.124GPa, 3.562MPa,
13.75KJ/m˛ and 8.276 MPA.m˝ respectively, for bio composite specimens
reinforced with pomegranate peels powder, while for bio composite
specimen reinforced with seed powder of dates Ajwa 105MPa, 4.187GPa,
3.316MPa, 10KJ/m˛ and 6.389 MPA.m˝ respectively. On the basis of these
results, it can be conclusion that the addition of natural fillings
nanoparticles (pomegranate peels powder and seed powder of dates ajwa)
to bio PMMA material, is one of the promising materials in use to
improve the strength of fracture to the base of dental kits. |
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Title: |
RFID based automated gate security system |
Author (s): |
Asha N., A. S. Syed Navaz, J. Jayashree
and J. Vijayashree |
Abstract: |
Here
has been rising enthusiasm for secure structure that must be attempted
and genuine and smart respond for the organizations and companions. RFID
(Radio Frequency Identification) is one of the consistent and speedy
techniques for perceive the material dissent. In the long-back the
institutionalized distinguishing pieces of proof are more perfect when
stood out from RFID because of their cost yet now day by day's RFID are
viably open and are more beneficial to use. Research has revealed some
exceptional enhancements which make its programming significantly
shorter and less requesting is an immediate consequence of supplanting
microcontroller with Arduino. Arduino makes the circuit and programming
a significant measure easier to get it. Paper relies upon security
access and control system using RFID and Arduino with GSM module. A
segment of the sensors are used like PIR, LPG for spillage area.
Security get to system is astoundingly beneficial to use at home, office
and business structures. |
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Title: |
Development of edible film from semi
refined iota carrageenan for sustainable food packaging |
Author (s): |
Danar Praseptiangga, Sarah Giovani, Dimas
Rahadian Aji Muhammad and Godras Jati Manuhara |
Abstract: |
Due
to its chemical and mechanical properties, iota carrageenan exhibits
great potential as a material for assembling polysaccharide-based edible
film. In this research, the physical and chemical properties of
commercial semi-refined iota-carrageenan derived from Eucheuma
denticulatum were evaluated. Edible films with varying concentrations of
semi-refined iota-carrageenan combined with glycerol as the plasticiser
were prepared and characterised. Results showed that both the physical
and chemical properties of semi-refined iota-carrageenan were in
accordance with the international standard. Increasing the semi-refined
iota-carrageenan concentration (from 1% to 2%, w/v) significantly
enhanced the thickness and tensile strength (TS) of edible film (p <
0.05). Degression in the percentage of elongation-at-break (EAB) and
water vapour transmission rate (WVTR) with higher concentrations of
semi-refined iota-carrageenan was observed; thus, incorporation of 2%
semi-refined iota-carrageenan is recommended for producing edible film. |
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Title: |
An information system for registration and
consultation of liver profile tests in the hospitals of the Department
of Huila - Colombia |
Author (s): |
Albeiro Cortes Cabezas and Yamil Armando
Cerquera Rojas |
Abstract: |
Hospitals in the Department of Huila in Colombia need hospital
information systems that allow them to guarantee the integrity and
readability of patients' information and also make it possible for
health information to be available at any point of care, regardless of
the institution provider of services where the patient is cared for.
Unfortunately, the Huila hospitals do not yet have these information
systems; which is why health care staff use old-fashioned, complex and
unstructured methods to store data about all types of results and tests
performed so that can be examined and analyzed by a physician and then
he cans make decisions. In this project an information system was
implemented to optimize the process of conducting the hepatic profile
tests in Huila hospitals in order to improve the organization of the
results, making access to these results much more comfortable and
efficient. The HL7 standard set was used as a guide for good
interoperability and to make the system scalable. Access can be made
through any web browser or any device due to a responsive web design was
used. The information system allows access to the data of a specific
patient and it is possible to export information from the database to
obtain different statistics. |
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Title: |
Development and substantiation of layout
of dust emissions purification systems used at mobile asphalt plants |
Author (s): |
Dmitry P. Borovkov, Elena O. Cherevychenko,
Konstantin O. Chichirov and Evgeny G. Ezhov |
Abstract: |
This
paper describes properties of dust particles emitted in the course of
asphalt plants operation, and analyzes design of various type dust
collection systems used for dust emission purification. Two layouts of
the dust systems including dust collectors operating with application of
swirling flow and with application of centrifugal dust concentrators are
proposed. A comparative analysis of both schemes efficiency is carried
out. |
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Title: |
A performance evaluation of YMAC a medium
access protocol for WSN |
Author (s): |
Jose de Jesus
Salgado Patron and Albeiro Cortes Cabezas |
Abstract: |
This
article studies the main performance characteristics of the YMAC
protocol, a medium access control protocol for sensor networks (WSN)
that uses multiple frequency channels for data transmission. YMAC was
designed taking into account the energy shortage characteristics of the
sensor nodes and seeking to achieve good performance under various
traffic conditions. Our contributions through this work are as follows:
first, a physical layer model corresponding to the radio
transmitter/receiver CC2420 was implemented in Qualnet®, including a
model of energy consumption and a model of the YMAC protocol based on
the specifications of the authors; second, a detailed performance
analysis of the protocol was made based on different metrics. |
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Title: |
Mobility improvement of heavy tracked
vehicles: The "pan" tank experience |
Author (s): |
Luca Piancastelli, Stefano Cassani,
Federico Calzini and Eugenio Pezzuti |
Abstract: |
This
paper shows that the sinkage of the tracked vehicle is the most
important parameter in its mobility. Power and fuel consumption follow
cubic power law with sinkage. So the usual strategy to increase power is
not the more convenient way to improve vehicle off road performance. The
Ground Pressure (GP) is the critical parameter. Power requirement goes
with the cubic power of sinkage. GP above 0.9 daN/cm2 should be avoided
at all costs. The best way to obtain this result on an existing design
is to increase track length. However it is easier to work on track
width. The easiest modification is to add "Duckbill extensions" in the
outer part of the shoe. This system was used on the Sherman Tank when
additional armor was added. With modern technology it is perfectly
possible to perform experimental tests with new shoes. This can be done
by manufacturing prototypes of high stress nitrided steel shoes, usually
with 300M high strength steel. Comparative fuel consumption is a good
index of vehicle performance. Also wheel diameter and width can be
increased to improve off-road performance. Specialized tracks for
different terrains should also be designed. The gravity center should be
kept slightly rearward. This attitude should not be excessive to keep
the pressure value more even possible along the track. In any case the
vehicle naturally assumes the backward inclination due to terrain
compression. Another important improvement is the addition of computer
controlled directional control to improve the accuracy of trajectories.
This is particularly important for tracked vehicles where turning
involves extremely high energy consumption. |
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Title: |
A novel design of rectangular microstrip
patch antenna for Bluetooth applications |
Author (s): |
Ahmed Shakir Al-Hiti |
Abstract: |
Bluetooth is a protocol used for data transmission in short range
communication from fixed or mobile devices. This technology is designed
for low power consumption having short range based on low cost
transceiver microchip in each device. Bluetooth devices use Radio
communication system, so it is possible for these devices to communicate
even when they are not in line of sight of each other but residing in
the defined range. Like other wireless devices, Bluetooth device needs
to have antenna in order to transmit data signals through the air to the
destination and receive transmitted signals from the source. In this
paper, the antenna has been designed by substrate of Fire Resistance 4
(FR4) material having dielectric constant of 4.4 with a conducting
radiating patch on the substrate and a conducting ground plane on the
bottom side of substrate. The ground plane has been partially reduced to
improve the antenna bandwidth. The antenna has been analyzed in terms of
various antenna parameters such as return loss (Db), gain (Db),
directivity (dBi) and return loss by Vector Network Analyzer. The
antenna has been designed utilizing Microwave Studio (CST) and also
fabricated by Network analyzer E5071C. The antenna design is appropriate
to be utilized to Bluetooth applications. It has been noticed that the
practical outcomes got through analysis the fabricated antenna that
matches with the CST simulator outcomes. |
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Title: |
Production of magnesium oxalate from Sea
Bittern |
Author (s): |
Hanem A. Sibak, Shadia A. El-Rafie,
Shakinaz A. El-Sherbini, M. S. Shalaby and Rania Ramadan |
Abstract: |
The
present study illustrates the details for precipitation of magnesium
from Bittern as magnesium oxalate. The target of study is to prepare
magnesium oxalate as a precursor for high purity MgO production. Bittern
solution is considered as a byproduct in saline, but it is an ore
reserve for many useful elements commercially produced at present based
on dolomite, sea water. Its rich composition in various elements;
especially magnesium salts gives bittern increasing economical concern
for different industrial applications. In the present study, the
mechanism of magnesium oxalate precipitation from bittern was
investigated using oxalic acid. The global reaction kinetics of
magnesium oxalate precipitation from seawater was determined using
different molar ratios and varied pH (1-6). The effect of temperature on
system kinetics was examined at temperatures
between 15 to 80°C. The effect of molar ratio on reaction
conversion was investigated from 1:1 to 1:1.8 (magnesium to oxalic
acid). The optimized parameters were found to be feasible to produce
pure magnesium oxalate with 99% conversion at stoichiometric molar ratio
at room temperature with pH=4. The effect of different
calcinations temperature was studied from 450°C to 1100°C. All
necessary instrumentation and chemical analysis needed for final
products characterization have been executed including, XRD, XRF, , and
SEM analysis. |
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Title: |
Enhancing the engineering properties of
cohesive soils using Portland cement |
Author (s): |
Orabi S. Al Rawi and Mohammed N. Assaf |
Abstract: |
Different kinds of engineering problems could be occurred as a result of
constructing foundations over cohesive soils. The majority of these
problems are concerning the soils' volumetric changes that may lead the
structure to be partially or totally failed; and accordingly, the idea
of this research was shined in order to select a suitable global method
to improve the properties of these soils in Jordan, and consequently to
minimize their bad effects on structures that were erected on them. The
methodology of this research was divided into two stages. The first of
these was reviewing for the available literature related to the most
applicable global methods in stabilizing fine grained soils; whereas,
the second stage was focused on carrying out several laboratory tests to
measure the influence of mixing different ratios of Portland cement
material with fine grained soil (obtained from an excavated site in the
Capital Amman) on the engineering characteristics of the original soil;
and then to recommend the best mix ratio to be adopted in stabilizing
fine grained soils in Jordan. Out of the conducted laboratory tests (Atterberg
limits, permeability, and unconfined compression) the results of these
tests showed that the plasticity indices had been decreased with
increasing the percentages of mixing Portland cement and then a decrease
trend in the soils' degree of expansiveness is expected to be occurred.
Increasing of cement percentages had also showed a decrease in the
coefficient of permeability of the soil. Moreover, a significant
increase in the values of unconfined compressive strength were noticed
as a result of mixing more cement ratios. Considering the results of
this research, it was concluded that mixing about 5% of Portland cement
with a cohesive soil had a pronounced enhancement on the engineering
characteristics of the fine grained soil after being mixed, and
therefore could improve its overall engineering behavior. |
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