Engineering and Technology Journal

In this work, Aِmplitude modulation mode-locked fiber laser is
studied,by using Ytterbium Doped Fiber Laser, single mode fiber,
operating with 1055 nm wavelength with 976 nm optical pump and AM
Mode-Locked by optical modulators. A grating pair is used to compensate
the normal dispersion. The effect of both normal and anomalous dispersion
regimes on output pulses are investigated. Master equation of the Modelocking
fiber laser is introduced .Pulse shapes for both dispersion regimes
are assumed after modifying (Ginzburg-Landu equation) GLE which is
essentially Generalized Nonlinear Schrödinger equation GNLSE and by
applying the moment method ,a set of five rate equations for pulse energy
,pulse width ,frequency shift ,temporally shift and chirp ,which solutions
described the pulse from round trip to the next and how they approach to
steady state values. To solve these equations numerically fourth order,
Runge-Kutta method is performed through Mat-Lab 7.0 computer program.
Result shows that, the output pulse width from the AM mode-Locked
equals to τ=0.8ps in anomalous and τ=1ps in normal regimes. The study
shows the stability of working in anomalous dispersion regime is better
than normal regime.

In this research, the Buoyancy heat transfer and flow patterns in a partially
divided square enclosure with staggered partitions have been studied numerically.
The partitions were distributed on the lower and upper surfaces of the box in
staggered manner. The height of the partitions was varied. The conduction heat
transfer through the fins (partitions) was also included. It is assumed that the
vertical walls of enclosure were adiabatic and its horizontal walls were maintained
at uniform but in different temperature. The problem was formulated in terms of
the stream function-vorticity procedure. The numerical solution based on the
transformation of the governing equations by using finite difference method was
obtained. The effect of increasing the partition height and Rayleigh number on
contour maps of the stream lines and temperature were reported and discussed. In
addition, the research presented and discussed the results of the average Nussult
number of the enclosures heated wall at various Rayleigh number and
dimensionless partition heights. The results showed that the mean Nussult number
increases with the increasing of Rayleigh number and decreases with the
increasing of partition heights. The distributed heat by conduction through the
partition increases with the increasing of the partition height especially at
(H/L ≥ 0.3). A comparison between the obtained results and the published
computational studies has been made and it showed a good agreement with
percentage error not exceed (0.54%).

In this paper, we present a new proposed error concealment algorithm to
improve the image quality degraded during its transmission over wireless channel.
Different error concealment strategies are applied to different locations of blocks in
order to achieve better visual quality. The proposed algorithm conceal the lost block
using Framelet Transform (FT), this is achieved by finding the average of framelet
subbands in neighbors of the lost block. Finally, the results of this algorithm compared
with the results of MultiWavelet Averaging (MWA) algorithm in terms of signal to
noise ratio (SNR) and human vision.

In this work, a proposed on-chip radio-frequency (RF) transformer design and
layout technique is presented to achieve high magnetic coupling coefficient and
low insertion loss by segmenting and interleaving wide primary and secondary
metal traces. Additional advantage of such technique is the mitigation of proximity
effect and current crowding. The proposed technique is verified and tested for a
square transformer, with different segmentation structures, using EMSight
simulator of Microwave Office 2007 (version 7.5) RF/Microwave software tools.
By using this design and layout technique, the magnetic coupling coefficient
improves from 0.49 to over 0.72 and lowers the minimum insertion loss from
1.56 dB to 1.18 dB at 4.5 GHz center frequency.

In this work Aِِrtificial Neural Network (ANN) is used as a classifier capable of
recognizing the most important features of the plant disease, with minimum error
value. Genetic algorithm has been used to minimize error values of the ANN
classifier. Error value of ANN classifier is defined as more than (%5). This ratio
is a threshold (cut-of-value) to determine if GA is executed or not after the ANN
classifier execution. Genetic algorithm execution results in either optimal solution
(%100) recognition or suggests a modified parameter to the ANN classifier
(specifically learning rate and number of neurons).The result obtained from
integrating neural network with genetic algorithm for classification plant diseases
indicates that the classifier recognizes most of input pattern with accuracy (96%).
Integrating neural network with genetic algorithm for classification plant diseases
implemented using Visual Basic version 6 programming

In this paper, a numerical study of the effect of a hot square cylinder placed on a
cooled elliptical enclosure of a laminar natural convection was carried out. This problem
is solved by using the partial differential equations, which are the stream vorticity
formulation for the flow and heat transfer in curvilinear coordinates. An elliptical
function is used, which makes the coordinate transformation from the physical domain
to the computational domain be set up by an analytical expression. About 48 tests are
performed for different ratios of the geometry such as, a /b =1.5,2.,3 , l /b = 0.25,0.5 ,
and Rayleigh number from 103 to 106, for two position of the major axis of the elliptical
enclosure, horizontal (HEE) and vertical (VEE). The results obtained in the form of
velocity vectors, streamlines, isotherms, and Nusselt number. The results show that, the
increase of the major axis of the enclosure ( a /b ratio) leads to increase the average
Nusselt number and decrease the flow strength for all Rayleigh numbers. Moreover, for
Ra≤104, there are a little difference in the results of ave Nu for all a / b and l / b ratios,
but if Ra increases, the change in the results is clear and large.

Transparent dielectric thin films of MgO have been deposited on glass
substrates at different oxygen pressure between (50-300) mbar using a pulsed laser
deposition technique to ablation of Mg target in the presence of oxygen as reactive
atmosphere. Structural, and optical, properties of these films have been
investigated. The films crystallize in a cubic structure and X-ray diffraction
measurements have shown that the polycrystalline MgO films prepared at oxygen
pressure (200) mbar and substrate temperature (150°C) with (111) and (002)
orientations. The films deposited at oxygen pressure between (150-300) mbar and
substrate temperature (150°C) exhibited highest optical transmittivity (>80%) and
the direct band gap energy was found to be 5.01 eV at oxygen pressure (200) mbar.
The measured of the resistivity of the film prepared at oxygen pressure (200) mbar
and substrate temperature (150°C) was 1.45x107Ω cm.

An experimental work was performed to study the effect of Zn, Cu ions on
the corrosion rate of carbon steel in distilled and tap water solution containing, 25
& 50 ppm concentration of Zn, Cu ions at pH range 4, 6 &8 in distilled water and
at pH8 in tap water at room temperature under both static for 10 weeks and 1, 2,
6 &12 hours with dynamic conditions. The obtained results showed that the
corrosion rate was increased in the presence of 50 ppm of Cu ions in tap water
(2.326 mpy) after 10 weeks, under static conditions, whereas under dynamic
conditions, it was reached (10.511 mpy), the presence of fine suspended solid
particles in the solutions may also cause an increase in corrosion rate due to their
movement over the carbon steel surface .In contrast, the presence Zn ions in
solution as sacrificial anode, therefore, the corrosion rate was 2.24 times less than
that in presence of Cu ions, at the same conditions. In distilled water, the
corrosion rates were decreasing slightly with adding Zinc and copper ions
comparing to absence of metals ions in solution except at pH4 in the presence
50ppm of Cu ions may be accounted due to the increasing in the conductivity of
the solution, under static conditions. At 25ppm of Zn ions lowering in corrosion
rate may be explained that the Zn ions were protected carbon steel surface by
sacrificial. In the absence of Zn, Cu ions were also carried out.

This paper presents a class derived from convolutional code called turbo code. The
performance of turbo code is investigated through examining the effect of different constraint
length, the effect of changing rate, and the effect of interleaver on the performance of turbo
code with presence burst errors.
The performance of turbo code is investigates through computer simulation, by using
MATLAB program.
The simulation encoder is composed of two identical RSC component encoder with parallel
concatenated, separated by interleaver.The turbo code simulation results are shown
graphically for different constraint length, in hard and soft decision. Also the simulation
results are shown for case with interleaver and without interleaver.

The aim of this study is to predict surface roughness of workpiece which
machined by ceramic cutting tool using SPSS program and compare the results
with the experimental values which performed under different cutting
conditions.Cutting speed (60,80, 90,100,110 m/min ) and feed rate ( 0.1, 0.08, 0.3,
mm/rev ) and depth of cut ( 0.25, 0.5 ,0.7mm ) . Experiments were conducted to
predict the surface roughness of workpiece , the estimated result shows that there
is good greement between average experiments values such as Ra ( 1.27,0.92 )
and predicted values of Ra ( 1.2024, 0.8254 ) and Ra (2.15 ) also value ( 2.2774 )
and experimental values of Ra ( 2.51, 1.78 ).

Hand lay- up technique was used to prepare sheets of epoxy composites reinforced
with woven roven (0ο-90ο) glass fiber in weight fraction (50%).The sheets were left to
solidify at room temperature (23± 2οC). The samples immersed in (HCL, KOH, distilled
water, Benzene, and Kerosene) for equal time at constant temperature (23± 2) Cο. The
tensile strength was calculated for the samples before and after immersion in different
chemical solutions.
The result shown that the tensile strength of the samples decreased after immersion in
different solutions, while (Kerosene) solution has maximum effect in decreasing the
tensile strength of the sample, the (Benzene) solution has minimum effect in
decreasing the tensile strength of the sample, and the other solutions (distilled water,
HCL, KOH) located between them in different ratio.
Finally the samples immersed in (HCL) solution has maximum relative mass
(minimum absorption resistance) while the sample immersed in distilled water has
minimum relative mass (maximum absorption resistance).

This article suggest a simple adaptive approach for tracking the
nonmaneuvering and maneuvering target, this tracking approach uses two states per
coordinate model to describe the target motion, the residue that provides from this
filter is forms the sufficient statistic to detect the existence of maneuver by fading
memory detector (FMD) with two-threshold value. When the residue exceeds one on
the threshold value, it is used to vary the maneuver noise spectral density (q) in the
two states Kalman filter model. This approach is consider as an extended and
enhanced for the Castella tracking filter [3] which proposed to track the maneuvering
targets for a low data rate track-while-scan (TWS) operation. However, the
performance of the suggested approach is tested under different flight environments to
compare the effectiveness of it with the performance of the Castella tracking filter.

Laboratory experiments were performed to study nutrient uptake by the
unicellular green microalgae (Chlorella vulgaris ) grown in batch system uses Al-
Asady Factory for Seeds and Animal Feed (Mahmodia/Iraq) industrial wastewater
as culture media .The initial concentration of C.vulgaris was 1*10 6 cells/ml with
48 hrs of incubation in wastewater at different temperatures ranges (20-35)°C
where changes in COD, BOD, total nitrogen and total phosphorus concentration in
the effluent were calculated.
The results show that the removal efficiencies of COD ,BOD ,nitrogen and
phosphorus are 88%, 89%,92% and 89% respectively. The optimum temperature
at which highest removal efficiencies were obtained was 30°C.

Pneumatic circuits are widely used in industrial automation, such as drilling,
sawing, squeezing, gripping, and spraying. Furthermore, they are used in motion
control of materials and parts handling, packing machines, machine tools, foodprocessing
industry and in robotics.
In this paper, a Neural Network based Fuzzy PI controller is designed and
simulated to increase the position accuracy in a pneumatic servo circuit where the
pneumatic circuit consists of a proportional directional control valve connected with a
pneumatic rodless cylinder. In this design, a well-trained Neural Network with a
simplest structure provides the Fuzzy PI controller with suitable input gains depending
on feedback representing changes in position error and changes in external load force.
These gains should keep the positional response within minimum overshoot,
minimum steady state error and compensate the effect of applying external load force.
A comparison between this type of controller with a conventional PID type shows that
the PID controller failed to keep the cylinder position with minimum steady state error
and failed to compensate the effect of applying external load force as compared with
the results when using a Neural Network based Fuzzy PI type controller. This is
because of nonlinearities that exist in the pneumatic circuit. Thus, the position
response using Neural Network based Fuzzy PI controller is better with an average of
improvement in position accuracy of (11 %).

The aim of this research is to design and simulate a fuzzy logic
controller (FLC) to control the cell multiplexing in Asynchronous Transfer
Mode(ATM) networking , which is a high performance cell oriented switching
technology that utilizing of small size packet to carry different types of service for
traffic and to show the effect of using the fuzzified variables (queuing message
length and the number of inputs) on cell flow rate (control action) on the output of
(FLC).The paper presents the previous works, principles of operations, cell
multiplexing, principles of fuzzy logic and internetworking with ATM network, the
design process of system and the output of simulation. The cell flow rate on the
output of fuzzy logic controller (FLC) which has been simulated depends on the
input variables, one of them is the queuing message (message length), and the
second one is the number of inputs. The simulation of fuzzy controller has been
executed by using (MATLAB). In the light of this research, an important
conclusion can be drawn, is that increasing of the fuzzified inputs variables means
that cell queuing will increasing so the (FLC) will achieve size of packet to be
large then the flow bit-rate of cell (control action) will decrease and when the
number of inputs decreases that will let to achieve a high flow bit-rate as
(M.Q=0.5,N=o.5,the control action (cell rate) =0.5 cells/s) and if (M.Q=0.2, N=0.5,
the control action(cell rate=0.77 cells/s).Using parameters such as ( message
length and No. of inputs)as fuzzified variables in controlling cell multiplexing
gives a flexible and a high speed responding to sudden changes in selective
variables and get bit-rate which reduces time delay for different types of
services(text, image, video and audio) which cause to get a high throughput, that is
the maximum throughput under FLC parameters (with message length and No. of
inputs) is (562.7Mbit/s) for text message, (568Mbit/s) for image message,
(563.4Mbit/s) for the video message and (563.4Mbit/s) for audio message

Information hiding is a means to conical and transmitting information using
apparently innocent carrier without depiction any suspicions. This paper presents a
new means for information hiding based images by using Hybrid of Parametric
Spline and DFT. A set of control points, which represents secret key, are selects
randomly from the carrier , and a curve pass by the selected control points is
implement using B-Spline. A hiding process for the secret message bits tacks
place on the spectral real part of the intensity pixels where the B-Spline curve
passes by using LSB technique, followed by the IDFT. The paper also presents the
information hiding features, and techniques for images, and Interpolation
techniques. The Objective fidelity criteria are depicts the improvements in
algorithm with an application example.

An approach for automatic 3D object re-construction using its shadow is
presented. The approach investigates the use of information inherited by the
generated object shadows to re-construct the object geometry. An algorithm is
developed that make use of object height information for the directions associated
with the incident light and the generated object shadows, hence, acquired height
features represents the object features that have actually obstructed the incident
light. The technique is tested using objects of different shapes. Close to real
measurements are gained and the overall accuracy of the system is found to be
within 0.75 mm using the adopted imaging hardware and setup. Obtained results
confirmed the validity of the proposed approach.

The work focuses on the preparation of hybrid polymer matrix composite
materials prepared from the unsaturated polyester resin as matrix reinforced by woven
glass fiber kind ( E-glass ) and graphite particles as first group of samples and the second
group of samples reinforced with woven Kevlar fiber kind (49) instead of glass fiber.
This work includes studying the effect of selected volume fractions ( 0% , 5% , 10% ,
15% , 20% ) of graphite particles with mixture of different particle Size of ( 25 μm – 106
μm ) on the properties of the prepared composite materials, Number of mechanical tests
were done,they include (Tensile, Compression, Impact, Flexural Strength, Shear Stress
and Hardness), which done at room temperature Result of the work shows that the
values of (Tensile stress, Tensile elastic modulus, Fracture Toughness, Hardness)
increase with the increase of graphite particle volume fraction for both groups samples.
As well as the values of the (Compression elastic modulus, Flexural strength, Shear
stress) increase with the increase of low values of graphite particles volume fraction for
both groups of samples. Where as the values of Impact strength of the prepared
composite material decreased with the increases of volume fraction of graphite particles
for both group samples. As well the result shows that the values (Tensile stress, Tensile
elastic modulus, impact strength, Fracture toughness) for hybrid composite materials
reinforced by Kevlar fiber are higher than values reinforced by glass fiber instead of
Kevlar fiber, While the values of (Compression stress, Flexural Strength, Shear stress,
Hardness) for hybrid composite materials reinforced by glass fiber are higher than values
reinforced by Kevlar fiber instead of glass fiber.

The Plain-Carbon steel are considered as one of the most common
metallic materials used in engineering and industrial applications due to its ability
in altering the micro-structures and mechanical properties as the result of carbon
content. These alterations have direct effect on the corrosion rate of steel by
building up galvanic corrosion cells between its microscopic phases. The effect of
carbon content on the corrosion resistance of Hypo-eutectoid plain carbon steels
having different carbon contents such as 0.05%C , 0.2%C , 0.35%C , 0.5%C , and
0.65%C have been studied using three testing durations which are 4 weeks, 6
weeks, and 8 weeks and different corrosion environments such as atmosphere,
fresh water, and salt water. The aim of the present work is to obtain the effect of
carbon content on the corrosion resistance of steels in different corrosion medium
by using the weight loss technique as a function of the corrosion resistance. The
results, which have been obtained during this work show that a correlation can be
made between corrosion rates and steels carbon content, and the corrosion
resistance decreases with the increase in carbon content.

This study is concerned with the effect of polymer quenching on some
properties of an alloyed tool steel (X155). Three different operations of heat treatment
have been done including quenching, quenching with tempering and quenching with
freezing. A comparison has been done between the effect of polymeric quenchant i.e.
water solution of poly vinyl alcohol (PVA) and the conventional quenchants
represented by distilled water, engine oil and food oil in having better properties. Tests
have been done to the original and heat treated specimens which were Brinell hardness
test, wear rate test and thermal conductivity test. Results had revealed that the heat
treatments generally enhance the properties especially the treatment of quenching with
freezing and in most cases the polymeric quenchants gave better results than the
conventional quenchants. Also a simulation to the results of the experimental work has
been done by using the Visual Basic language, and the results gave us an indication to
the behaviour of specimens’ properties at different concentrations of polymeric
quenchants over the range used in the experimental work, beside the great possibilities
of the program in display the experiments which help in training engineers in heat
treatment and testing fields.