Print ISSN: 1681-6900

Online ISSN: 2412-0758

Volume 28, Issue 12

Volume 28, Issue 12, June 2010, Page 571-2496


Numerical and Experimental Analyses for Effect of Welding Currents on Cooling Rates in (M MAW) Process

Abbas Sh. Alwan; Jalal M. Jalil; Muna K. Abbass

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2276-2293

In this study, Manual Metal Arc Welding (MMAW) is carried out for low
carbon steel (AISI 1015) with using electrode (E7018). Direct current straight
polarity (DCSP) with the joint geometry of single -V- butt joint and weld one pass
are used for plate of thickness 8mm. experimentally, obtained temperature
distribution in fusion zone which is measured by insert the thermocouple in weld
metal. Cooling rates are determined for the fusion zone at different welding
currents (100, 120 and 140) Amp with constant welding speed at 3.2mm/s.
Numerical analysis by using the Control Volume Method (CVM), applied to threedimensional
heat transfer model to determine the cooling rate in fusion zone.
Cooling rates models are helping in prediction the microstructure (phases, grain
size and volume fraction) and microhardness distribution in weld metal and heat
affected zone. The comparison of cooling curves between numerical and
experimental work have a good agreement, so that deviation was in range ( 6℅ -
21℅) which is confirming the capability and reliability of the proposed numerical
heat transfer model in manual metal arc welding. The best result for cooling rates
when applying mathematical model is at welding current 140Amp.

Modeling and Simulation of Flue Gas Desulfurization Using Slurry of Fine Activated Carbon Particles

Asmaa I. Eliass; Neran K. Ibrahim

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2294-2307

The main objective of the present work is to investigate the
feasibility of using a slurry of fine activated carbon particles,
dp<1mm, in a fixed bed reactor for the removal of sulfur dioxide
from simulated flue gas (air, SO2) stream. A mathematical model
governing the desulfurization process was proposed. The partial
differential equations which describe the adsorption of SO2 from a
moving gas stream to the sorbent bed were solved using a finite
difference method. The kinetic parameters of the mathematical
model were obtained from a series of experimental desulfurization
runs carried out at isothermal conditions and different operating
conditions; bed temperature (333K-373K), initial SO2 concentration
(500ppm-2000ppm) and static bed height (10cm-24cm). The results
showed that the use of fine activated carbon particles improved the
removal efficiency to about 97%. The verification of the simulation
and experimental results showed that the proposed model gave a
good description of the desulfurization process with 95% confidence
level

Nonlinear Behavior of Steel-Concrete Composite Beams Curved in Plane with CFRP Strips Bonding

Ahmed F. Kadhum

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2308-2324

This paper deals with the behavior of structural steel-concrete composite beams
curved in plane. The analytical investigation included the use of three dimensional
nonlinear finite elements to model the performance of the composite beams
strengthened with CFRP strips by using (ANSYS 11.0) computer program. The
numerical results showed very good agreement with the experimental results reach
to 100% before the strengthening, while the increase in strength after the curved
strengthened with CFRP strips 32% for the curve beam with L/R equal to 0.05 and
48% for the curve beam with L/R equal to 0.10 and 53% for the curve beam with
L/R equal to 0.25.

Experimental Investigation of The Steady Motion of Spherical- Cap Bubble

Hussein Ali Hussab; Mohsin Abbas Mashay

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2325-2336

The aim of the present work is to study the hydrodynamics of sphericalcap
bubble, rise bubble velocity, shape of bubble, and drag coefficient. The
experimental work of two-phase ,air-water system was carried out using a Perspex
column of 14.5 cm diameter and 180 cm height. A known volume of air was
supplied to the cup from a syringe. The single gas bubble rose through the
entrance region by turning the cup instantaneously. The rise bubble velocity was
measured by visual observation. In order to measure the terminal velocity an
electronic timer (Stop-Watch) was used. The drag coefficient of air spherica–l cap
bubble rising in water was measured and found to be a value between (2.8-3.8) for
all Reynolds number. The experimental results are compared with the theoretical
results of some investigators.

Proposed 256 bits RC5 Encryption Algorithm Using Type-3 Feistel Network

Yossra H. Ali

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2337-2352

Proposed 256 bits RC5 is an improvement to RC5, designed to meet
the requirements of increased security and better performance. Proposed
256 bits RC5 algorithm makes use of data dependent rotations. One new
feature of proposed 256 bits RC5 algorithm is modified its design to use
four 64-bit registers rather than two 32-bit registers. The proposal 256 bits
RC5 algorithm using Type-3 Feistel network which is iterated simple
function 20 times. An Avalanche Effect of RC5 is about 31.372 if we
change the same amount of information in key for 256 bits RC5 then the
Avalanche Effect is about 142.909. The proposed algorithm is resistant to
matching and a dictionary attack which is increased the security of the
previous RC5 algorithm by using block size of 256 bits instead of 64 bits.

Approximate Solution For Linear Fredhlom Integro-Differential Equation By Using Bernstein Polynomials Method

Waleeda S. Ali

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2353-2360

In this paper, Bernstein polynomials method is used to find an
approximate solution for Fredholm integro-Differential equation of the second
kind. These polynomials are incredibly useful mathematical tools, because they
are simply defined, can be calculated quickly on computer systems and represent a
tremendous variety of functions. They can be differentiated and integrated easily.

Reliability Based Design of Pile Raft Foundation

Tania M. Al-Ani; Namir K.S. Al-Saoudi

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2361-2378

The Combined Piled Raft Foundation (CPRF) is a modern concept in
which the total load coming from the superstructure is partly shared by the raft
through contact with soil and the remaining load is shared by piles through skin
friction and/or base capacities. A CPRF system is economical compared to the
traditional “piled foundation” design where the pile cap is assumed to be sustained
by piles only.
A “case study” (Basrah elevated water tank project) is studied thoroughly
in this work. The 1365 m3 elevated water tank located at 3 nearby sites was
originally designed as a piled foundation with 25 bored piles for each site (0.7m
diameter and 24m length). Theoretical analysis reveals that the piles have an
allowable capacity of 2245 kN. On the other hand static pile tests were preformed
on 17 piles out of 75 piles and it appeared that the allowable capacity
demonstrated erratic values below the expected pile capacity.
A re-analysis of the pile raft is performed establishing the CPRF concepts.
The case study was modeled by STAAD Pro computer package to determine the
loads on both piles and soil with the corresponding settlement values.
The reliability aspects of behavior of both “piled foundation” and CPRF
are investigated. In this approach the influence of autocorrelation for the stiffness
modulus (of both piles and soil) and raft thickness are considered.
The safety of both systems is obtained in terms of traditional factor of
safety (FS) and reliability index (b). The results showed that the “piled
foundation” system is “unsafe” for 3 criteria for both FS and b. On the other hand,
the CPRF is “safe” for the 4 criteria for FS concept while it is “unsafe” for 3
criteria for b.

Design and Simulation of N-Way In-phase Equal power Wilkinson Power Divider

Abdul Kareem K. Abdul Raheem

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2379-2391

In this paper, three designs of Wilkinson Power Divider (WPD) at 9.0 GHz
center frequency are proposed. The first design is 2-way in-phase equal power
outputs implemented on the Roger RT-duroid 6006, PTFE ceramic, relative
permittivity = 10.2 r e and thickness of substrate material h = 0.365mm. The
second design is 4-way and the third design is 8-way in-phase equal power dividers
are implemented on the same substrate. The third design is a new shape of 8-way
WPD consists of feeder connected with four WPD via cut cortex rhombus to
achieve matching with inputs. All designs are simulated by using CAD
(Microwave Office 2000). The simulation results demonstrate that the power
divider works well at assigned operating frequency with compact size. Low
insertion and high isolation are achieved.

Artificial Neural Control of 3-Phase Induction Motor Slip Regulation Using SPWM Voltage Source Inverter

Lina J. Rashad; Fadhil A. Hassan

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2392-2404

Variable-Voltage Variable-Frequency control represents the most
successful used method in speed control of 3-phase induction motor, which is
implemented by using PWM techniques. This paper proposes modeling and
simulation of sinusoidal PWM voltage source inverter as a VVVF A.C drive. The
dynamic model, simulation of 3-phase induction motor, and open loop speed
control system is proposed too. The PI closed loop controller of rotor slip
regulation is illustrated as a traditional speed control method, which gives stable
operation behavior of motor speed in the constant torque region with settling time
=0.5 sec and maximum overshot =20%, but unstable operation in the field
weakening regions with steady state error =15%. The Artificial Neural Network
(ANN) is going to be the modern type of speed controller. This paper proposes
NARMA-L2 (Nonlinear Autoregressive-Moving Average) neural network as an
improved Artificial Neural Network technique, and trained as a close loop slip
regulation controller, which gives an ideal performance with settling and rise time
= 0.18 sec, maximum overshot and steady state error less than 1% in different
speed range and constant air gap flux, including the field weakening regions.

Digital Video Automatic Segmentation Algorithms Using Edge Detection

Faten Hassan AL; Kathy

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2405-2412

With the increasing use of digital techniques in cinema, television and
photography, there is a growing need for software capable of efficiently editing
and compositing high quality digital images. This research captures video scenes
after extracting frames from video file .Video scene change detection is a
fundamental operation used in many multimedia applications and it must be
performed prior to all other processes.
One goal of the work presented in this research is to develop technique for
video scenes detection, by detecting the appearance of intensity edges in a frame
that is at a fixed distance away from the intensity edges in the previous frame. The
results of testing the program against abase line of different types of digital videos
are represented graphically and analyzed to investigate how well the program can
detect different filming techniques.

Studying The Electrical Properties Of Piezoelectric Material (PZT) Prepared By Organic Acid Precursor Method

Abdul karim Ziedan Khalf Al- Jebory; Sabah M. Ali Ridha

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2413-2424

The compound of piezoelectric nanopowders with a general system PbZxrTi1-xO3
(PZT) at different concentrations (x =0.3, 0.5 and 0.7) were prepared by using
organic acid precursor method. Disc shaped samples of each concentrations were
sintered for two hours at temperatures in the range of (700-1100ºC). The perovskite
structure was determined by X-ray diffraction spectroscopy, and the dielectric
properties were investigated for all samples. The dielectric studies of the
compounds as function of temperature in the range (room temperature to 450ºC) at
frequency 1 KHz shows that the compounds undergo a phase transition of diffuse
type from tetragonal phase to cubic phase. Maximum values of electrical properties
such as (Dielectric constant 1200, loss factor 1.05) were found for PZ0.5 T0.5
compounds, and these properties decrease with increasing of (Zr or Ti) additives.
The effect of frequency in range (103-105 Hz) on electrical properties is low with
stability in dielectric constant and dielectric loss.

Central Fault Tolerance For Dual Database Server Real Time System

Asia Ali Salman; a Abdu-Aljabar; Rana Dhia

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2425-2441

The aim of this article is to find an efficient method to detect fault in dual
database server which is working on critical environment real time system (such as
power and water distributed environment).
In traditional dual database server the fault tolerance is embedded in each
server. So when there is any defectiveness, each server try to uncover the error in
separate way. This led to increase the load on each server and job lateness.
This paper proposes a central fault tolerant method for dual database server
through a centralized control, so that the fault will be more controlled and
manipulated and the load will be less in each server since problems detection and
correction will not depend on dual server but it will be centralized.It showed
practically how the dual server worked under fault conditions and critical
environment such as distributed real time systems.

Mechanical Properties of High-Strength Fiber Reinforced Concrete

Zaid Muhammad Kani Al-Azzawi; Kaiss Sarsam

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2442-2453

Experimental results of this work in addition to a wide range of data from previous work
were analyzed to study the mechanical properties and strength of high-strength concrete with and
without fibers. Different types of steel fibers (straight, hooked, duoform, crimped) with a volume
fraction ranging from 0 to 2 percent were studied. The concrete compressive strength ranged from 41
to 115 MPa. The influence of fiber on the compressive strength, axial strain, modulus of elasticity,
Poisson's ratio, modulus of rupture, and splitting tensile strength, were studied. In addition to that,
size effect of control specimens on high-strength fiber reinforced concrete materials, was observed.
The main conclusion indicates that high-strength concrete (HSC) properties, especially with fibers
are significantly different from normal-strength concrete (NSC).

Design of Compact Hilbert Microstrip Bandpass Filter For Modern Wireless Communication Systems

Jawad K. Ali; Yaqeen Sabah Mezaal

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2454-2468

This paper presents a new microwave narrow-band bandpass filter with a
miniaturized size for use in modern wireless communication systems. The
proposed filter design topology is based on a single-mode microstrip resonator
constructed in the form of Hilbert fractal geometries from 2nd to 4th iteration levels.
The space-filling property the proposed filter topologies possess, has found to
produce reduced size structures corresponding to the successive iteration levels.
Many filters have been designed for the Industrial Scientific Medical band (ISM
band) applications at a design frequency of 2.4 GHz using a substrate with a
dielectric constant of 10.8 and thickness of 1.27mm. The performance of each of
the resulting bandpass filter structures has been analyzed using a method of
moments (MoM) based software package, Microwave Office 2007, from
Advanced Wave Research Inc. Results show that these filters possess good
transmission and return loss characteristics, besides the miniaturized sizes gained;
making them the design specifications of most of wireless communication systems.

A Comparison Study of Different Ceramic Filler on Mechanical and Thermal Properties of Glass, Carbon, Kevlar / Polyester Composites

Sarmad I. Ibrahim; Raghad O. Abas; Falak O. Abas

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2469-2479

Fillers play a major role in determination of the properties and behavior of
particles on (glass, carbon, and Kevlar fiber) reinforced polyester composites.
These particles are fabricated using both alumina (Al2O3) and silicon carbide (SiC)
particles as filler materials for such systems. The effect of these two different
ceramic polyester composites are investigated at different additive ratios as (0.2,
0.4, 0.6, 0.8, 1.0) volume fraction.
Comparative analysis shows that the bending distortion, Hardness, and
Impact resistance are affected by the type and content of filler particles, where
both impact and Hardness is increased with increasing volume fraction specially
in case of (0.5) volume fraction for both filler particles and decreased for bending
distortion specially in case of glass fiber/ polyester at (0.5) volume fraction for
both filler particles. Also high electrical properties for all filler/ fiber/ polyester
composites.
It is shown that silicon carbide (SiC), have better filler characteristics
compared to those of alumina (Al2O3) .Hopefully, these results provide a cost
effective solution to composite applications.

Some Numerical Methods For Solving Fractional Parabolic Partial Differential Equations

Akram A. Al-Sabbagh; Ibtisam K.Hanan; Osama H.Mohammed

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2480-2485

The aim of this paper isto approximate the solution offractional
parabolicpartial differential equations using two numerical methods which are
Bellman's method (make use of Lagrange interpolation formula) and the method
of lines. Fractional Parabolic partial differential equations are transformed to a
system of first order ordinary differential equations that are solved using a Runge-
Kutta method. An illustrative example using thesemethodsare also presented and
compared with the exact solution.

Study The Effect of Co Concentration In Nico Thin Films on Some Structure And Mechanical Properties

Alaa A. Abdul-Hamead

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 2486-2496

Electroplating process has been used to prepare Magnetic NiCo alloys thin
film with thickness of 1μm on brass alloy substrate using different Co
concentrations .Surface morphology, XRD, atomic absorption, apparent density,
open porosity, stresses and microhardness of pure and alloys thin film has been
investigated. Results indicated that the pure and alloy of thin films was
polycrstaline with (111) domain orientation changed to (101) with increment Co
deposited percentage, which is spontaneously increase with Co molarity increased
in the deposition solution.Microstructure for thin films change from nodular
structure to pyramidal and dendritic structure with changing Co content in film.
Apparent density for prepared thin films was less than theoretical density about
(8g/cm3), and varying with actual Co deposited content. Open porosity also
reduced in general with increment of Co content. Mechanical properties shows
alteration in internal stress behavior of deposited thin films from compressive
stress to tensile stress at (0.05M) of Co. Microhadness also increased with
increasing in the Co percentage in deposited thin films,to about(467Kg/mm2).

Evaluating Test Image Quality as a Function of illumation

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 571-583

The optical imaging systems, do not give a perfect and ideal image. But
mostly give images with limited resolutions i.e. give images with blur edges. This
blurring attributed to two main reasons. The diffraction of light and Aberrations of
the optical imaging system. The most important information and details in the
image that contained in image edges. The fidelity criteria are evaluate the quality,
depending on the whole image plane or in homogenous image regions. so we dealt
, in our study , with image estimation depending upon calculating the contrast
(mcontrast) of edges regions . Specifying the edges in the image is made by using
soble operator . Also , several different and new methods were proposed to
calculate the contrast . Contrast is one of the most standards of the checking image
quality. In addition the value of the absolute central moment (ACM) and the
standard deviation (s ) one calculated to evaluate the images quality with
different lighting.

A Theoretical Investigation Of Reaction Properties In Highly- Doped N-Gaas At MIR Wavelengths

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 584-593

In this work, a theoretical multi-layer structure was presented to investigate the
nonlinear optical behavior induced by free electrons in a thin layer of highly-doped
n-type GaAs at the MIR wavelengths. The multi-layer structure is considered to
enhance absorption by a semiconductor thin layer. The intensity-dependent
reflection properties were analyzed and the results explained the possibility to
increase the optical sensitivity of the multi-layer structure compared to that in
GaAs bulk.

Computer- Aided Setup Planning of Machine Tools For Different Machining Operations

Engineering and Technology Journal, 2010, Volume 28, Issue 12, Pages 594-603

Most of machining &manufacturing operations done by different
machining machine tools, where the machining parts pass through different
machining operations, starting from raw material to the final product. Machining
parts accuracy depends on machine accuracy, inaccuracy of machine leads to long
operation time &high cost. In this research planning turning operation machine
including cutting tool planning by finding the best setting up size of cutting tool.
The practical application has been done by machining (12) samples in different
size on turning machine &finding best setting up size for the cutting tool from the
surface of the machining part by using dotted diagram& setting up size Equation,
we found best setting up size=41.70 8 mm for different operations of turning
machine. So finding the best setting up size is necessary to decrease the times of
turning machine tool setup (increasing the time between tool re-setup) to decrease
the machining time& cost to minimum as much as possible. Using Q-Basic
language to build computer aided Program to find optimum setting up size.