Engineering and Technology Journal

This study deals with the evaluation of discharge coefficient of semicircle
crested weir extending across the full width of the channel (suppressed).It is stable
over flow pattern, easy to pass floating debris, and has large coefficient of
discharge. Data obtained from laboratory experiments provide information on
head – discharge relationship for three models with different radius of curvature.
Each model has an empirical head- discharge equation. The momentum equation
is applied to derive discharge per unit width. The predicted values of discharge
coefficient for the proposed models based on direct discharge measurement & the
derived discharge equation. The proper application of this study is an equation
show that the discharge coefficient is proportional with upstream head above weir
crest & inversely with the radius of curvature.

Modern wireless communications require wide band width resulting in an
increased demand for Ultra-Wide Bandwidth antennas. This paper proposes a design
for a compact, ultra wide bandwidth antenna with metamaterial. It will be small in size
and utilize the best performance of spaced array with a good correlation between the
antennas. The antennas are designed with metamaterial structures embedded in
substrate. Using the size reduction of double the existing type of antennas, the proposed
model exhibits the best in radiation bandwidth, mutual coupling, radiation pattern,
return losses, cover UWB frequency range very well in (3.1-10.6)GHz and
polarization with a good Isolation of more than 22dB .

Three numerical methods were implemented for solving the eight-order
boundary value problems. These methods are Differential transformation method,
Homotopy perturbation method, and Rung-Kutta of 4th Order method. Two
physical problems from the literature were solved by these methods for comparing
results. Solutions were presented in Tables and figures. The differential
transformation method shows an effective numerical solution to linear boundary
value problems. This considers an important contribution in solving boundary
value problems by the differential transformation method.

This work focuses on studying the effect of cutter width on the surface roughness
and cutter run out during horizontal milling operation, since the contact width in
milling operations depends on the cutter geometry, especially (cutter diameter and
width). So, three types of helical plain cutters with different widths are taken,
(40,63,80mm), used in horizontal milling , when other cutter geometry parameters are
constant. As for workpiece material, it was from (structural steel (1.0402)) according
to (DIN:C22) specifications, with different cutting conditions (spindle speed, feed
rate, and depth of cut) for each cutter, results show that milling cutter, which has
larger width (80mm), gives large surface roughness and cutter runout compared with
other two types. The results show that the surface roughness and cutter runout
decrease with the increase of spindle speed under constant feed rate and depth of cut.
While surface roughness and cutter runout increase with increase of feed rate for
constant spindle speed and depth of cut .Both the results of fixing spindle speed and
feed rate with changing depth of cut show that surface roughness and cutter runout
increase with the increase of depth of cut .In addition, cutter runout has a large effect
on the surface roughness because it causes an increase in surface roughness of
workpiece. Also surface roughness decreases at cutter (80mm width) which causes
larger surface roughness than cutters (63mm and 40mm width),. For certain
machining parameter as the spindle speed increases from (100 to 210 rpm), feed rate
(35 mm/min) and depth of cut (0.1mm), the surface roughness value decreases from
(1.61333 to 1.418333) μm at cutter (80mm width.) .When the cutter (63mm width) is
used, the surface roughness decreases from (1.5222 to 1.3182) μm , and at cutter
(40mm width) the surface roughness decreases from (1.4111 to 1.212) μm. Also in
this study, multiple linear regression model is used within (SPSS) software to predict
the experimental data for each surface roughness and cutter runout for different three
cutters and results show from comparing between predicted and measured values that
(SPSS) software gives high prediction accurate

In this paper, dry sliding wear and corrosion behavior of Cu + 13wt% Al +
3.8 wt% Ni was prepared by powder metallurgy. Dry sliding wear has been
studied based on pin on disk at constant velocity and constant sliding distance
.Corrosion behavior in 5 wt% NaOH solution based up on potentiostatic ( Tafel )
has been presented for base shape memory alloy ( Cu + 13% Al + 3.8 % Ni ) in
two cases austenitic and martensitic phase state . Further more , the effect of Fe
additions as ( 0.4 , 0.8 and 1.2 wt% ) on the sliding wear and corrosion behavior of
base alloy has also been studied .It is clear that Cu Al Ni shape memory alloy in
martensitic state has more wear resistance than in austenitic structure . Also ,
corrosion resistances are better than in martensitic structure because the alloy has
corrosion current density as 336.45 μA/cm2 in martansitic where as the corrosion
current density is 633.62 μA/cm2 in austenitic structure . Further more , when the
iron content increases , wear and corrosion rate increase too

This study includes enameling and study corrosion behavior of low carbon steel
(carbon continent =0.11%) in different types of corrosive media like the H2SO4, HCL
and NaOH both acidic solution (H2SO4, HCL) has PH= 2 with resistance acid solution
enameling and alkaline solution (NaOH) have PH= 12 with resistance alkaline
solution enameling. enameling process includes preparing and applying of frit by
ground coat method.
The corrosion rate calculated using weight loss method at temperature range (30, 40,
60, 90)oC for acidic and (30, 40, 50, 60) oC for alkaline solution. The results indicate
that corrosion rate increase with time and temperature for both H2SO4 and HCL
solution, while corrosion rate for NaOH solution decreases with time due to the
formation of unsolvable compounds on sample surface. These compounds may caused
insulation laminar reduced corrosion rate, while corrosion rate increases with
temperature because distortion of this layer

Shuttle Radar Topographic Mission (SRTM) has created datasets of global
elevations that is freely available for modeling and environmental applications. The
global availability (almost 80% of the Earth surface) of SRTM data provides
baseline information for geospatial applications such as mapping, hydrology,
navigation, GIS applications, and reconnaissance. Assessment of the accuracy of
SRTM requires regional studies involving points with known elevations at higher
level of precision than the SRTM, usually measured with Global Positioning
System (GPS).
This study based on datasets collected with a differential GPS system in different
locations in Iraq. These measurements were corrected with differential methods to
reach to sub – centimeter accuracy. Statistical analysis included estimation of
absolute errors by Root Mean Square Error (RMSE), Standard Deviation (SD).
RMSE was found as (5.15m) for Iraq and the SD was (3.93). This is higher than
the standard SRTM-DEM accuracy which is (16m)

Robust adaptive tracking control algorithm is proposed in this paper for single
link robot arm position control. A model reference adaptive control algorithm is
applied to control the angular position of the robot arm by tuning the parameters
of the controller. Each parameter of the adaptive controller tuned separately then
the controller will reflect the parameters to follow the reference model. The
control algorithm was thoroughly tested using the dynamic system modeling
package Matlab\Simulink. Comparing with adaptive neural network controller,
this technique can provide better angular position control for variable load
applications

The electromagnetic interference caused by power transmission lines to oil and gas buried pipelines is under investigation for many years. Especially during fault conditions, large currents and voltages are induced on the pipelines that may pose danger to working personnel or may accelerate the corrosion of the pipeline’s metal. In this research, the Joule effect of eddy currents induced in the oil buried pipelines due to the magnetic fields produced by nearby 400kV transmission lines in the South of Iraq have been computed. A computational model based on 2D finite element approach to calculate the heat generation rate. The influence of different earth resistivities for homogeneous earth model during steady state and fault conditions is analyzed. A mitigation system using mitigation wires has been simulated to reduce induced eddy current heating effects to the safety limit

This work presents a comparison of the flow region in baffled and unbaffled
bubble columns with Newtonian and non-Newtonian liquids. The experiments
were carried out in column of 15 cm inside diameter and 2m height with aspect
ratio (L/D=4.5), using perforated plate gas sparger, 54 holes of 1mm diameter,
and with free area of holes to cross sectional diameter of vessel 0.24. The two
phase system consists of air and non Newtonian liquid of polyacrylamide
(PAA).
The gas holdup was measured and the transition point from homogenous to
heterogeneous region was calculated under different concentrations of PAA (0,
0.01, 0.05, and 0.1)wt% in baffled and unbaffled columns. The results show that
the measured values of gas holdup are increased in the presences of baffles in
homogenous region, while, they decrease in heterogeneous region.
The transition points of gas holdup and superficial gas velocity were estimated
from drift flux plot. It was concluded that they were decreased with increasing
viscosity and increased in the presence of baffles.

In this study, a general linear one-dimensional finite element beam model is
developed for the analysis of the three layer composite steel- concrete- steel beams
which are a special case of the multi-layer
Connectors, concrete layer thickness, plate thickness, type of loading and
concrete compressive strength composite beams. The model is based on partial
interaction theory of composite beams where the flexibility of shear connectors is
allowed. A program is constructed using VISUAL BASIC language to analyze
this type of beams.
Numerical applications are presented to demonstrate the validity and
applicability of the present method. A parametric study is carried out to
demonstrate the effect of some parameters including the variation of shear
stiffness of shear on the behaviour of three-layer composite beams. The results of
the proposed programmed model shows a good agreement with those obtained by
finite elements method using ANSYS program (Release 11, 2007. The models
used in ANSYS program are shell element, brick element and combine element to
simulate the behaviour of steel plates, concrete part and shear connectors
respectively.

The design issues for a current injection vertical cavity surface-emitting lasers
(VCSEL) operating at 1550 nm is presented using photonic crystal (PC) technology.
The design is based on PC slab containing multihole rings with a single defect is
introduced at the center which acts as a waveguiding core

There are numerous search methods in A.I used to find the solution path to a
subjected problem, but many of them return one solution path with no consider it is
the optimal or not.
The aim of this work is to find a direct path from the start state to the goal state
such that it is the shortest path with minimum cost (the optimal solution path).
We develop the backtracking algorithm in order to find the optimal solution
path, such that all possible paths of the problem that expected to contain the optimal
solution path can be checked, also we use a heuristic function depends on the actual
cost of transition from one state to another. And in order to reduce the search time
we discard any path that it is not useful in finding the optimal solution path.
The proposed algorithm was implemented using visual prolog 5.1 and tested on
tree diagram and the result was good in finding the optimal solution path (with
efficient search time equivalent to O(bd/2) and space complexity O(bd) in worst
cases).

The multiconfiguration Dirac–Fock MCDF wavefunctions has been employed to
calculate the energy contributions of the Breit interaction and radiative quantum
electrodynamics QED corrections to the ground state energy level for the carbon
isoelectronic sequence and for elements 1 £ Z £ 104 in the periodic table. These
corrections are treated pertubatively

In this work, the effect of variation of several variables on linear free and
transient vibration response of combined cylindrical-conical shell is presented.
The shell is made of polyester resin reinforced by a continuous type E-glass. The
problem is solved experimentally and numerically for both orthotropic and
isotropic shell structures. Clamped – free boundary conditions is used for the
analyzed structure. The experimental program is conducted using digital
oscilloscope with built-in FFT analyzer with aid of hammer transducer. Software
named SIGVIEW was used to calculate the natural frequencies experimentally for
each specimen. The numerical investigation is adopted using ANSYS Finite
Element software to verify the experimental results which show how the natural
frequencies and mode shapes are affected by changing these variables. The results
show that this investigation will assist the study for the advanced development of
the cross-ply laminated composite coupled shell structures

In this paper the proposed method based on two encrypted algorithms (Public
key, and Block cipher) at the same time, it allowed a sender to encrypt the multicast
packet and forward it into the packet network on the optimal distribution tree. The
packet may be replicated at the optimal locations in the network and delivered to all
the receivers. The receivers are capable of decrypting the packet and forwarding the
packet in the secure network environment. The sender must encrypt packets using a
shared key that all the legitimate receivers use to decrypt thepackets. The security of
the system is based on the ability to control the distribution of the keys only to those
legitimate receivers

This paper investigates the household behavior of Al-Kut City residents
towards solid waste management. The paper is the outcome of a house to house
survey of 560 households per week; the sampling program was based on Random
Uniform Sampling for seven months period (January to July 2009), covering different
parts of the city. Samples were collected and analyzed periodically.
Solid waste generation and composition in Al-Kut City (like other countries)
is typically affected by population growth, urbanization, and improved economic
conditions.
The daily per capita waste generation in Al-Kut is 0.53 kg which is lower in
the low- economic level zone in the city than in other zones. Among the total waste
generated in Al-Kut City, 70.38% is food waste, 4.19% plastic waste, 2.44% metal
waste, 2.32% glass waste, 3.36% paper waste, 6.75% textile waste, while the
remaining percentages represents miscellaneous combustible and non combustible
materials. Quantity and composition were measured in order to be used in a new
MSW management plan.

The two-point boundary value problems for the 4th order ordinary
differential equations with a positive coefficient multiplying at least one of
derivative terms are solved with two numerical methods. These numerical
methods are the (Rung- Kutta of 4th Order) and (Rung –Kutta Butcher of 6th
Order). The 4th order ordinary differential Equations problem had been
transformed to pair of second Order differential equations, which were solved
together by the suggested methods. An initial value of the dependent variable
had been predicted and corrected to some error. The two studied methods were
tested on a physical model problem from the literature for comparing results.
Solutions were presented in Tables and figures. good agreements were appeared
in applying the studied methods

Limited water resources formed a great challenge for the specialists in
water resources engineering. This challenge is represented by “ design and manage
the projects” connected with water resources in such a way that insure providing
suitable quantity and quality of water.
In this research, the discrete differential dynamic programming approach
is used to find the optimal monthly operation of Haditha Dam by adopting an
objective function to minimize the release and storage penalty. The historical
inflow data of 240 months, from Oct. 1987 to Sep. 2007, formed the input data
to the optimization model to find the (upper and lower) rule curves.
Preserved the logical state of reserve storage, i.e., save minimum
operation storage just before the expected start of the effective flood and maximum
operation storage at the end of the flood season.
The optimum operation policy showed that Haditha reservoir can contain
the probable maximum flood of Euphrates flood during the considered operation
period, 240 months, and the water level in the reservoir above the operation level
of the reservoir during the same period, while this policy gave deficit in satisfying
the demands downstream Haditha Dam The deficiency was noticed during ( 152 )
months.

Recently noise become the most environmental pollutants in almost of
society establishments specially in schools .This research was done to evaluate
noise level in some primary schools in Baghdad and to study the sources of this
noise as well as the factors which effect on its level .Results show that noise levels
in all of these schools were higher than international limits due to unsuitable
location for these schools, missing for acoustical treatment in their classrooms and
number of pupils with unsuitable area of classrooms, in addition this research
related noise level to the experience of teachers and found that lower levels were
measured in classes with an experienced teacher and the higher level when trainee
teacher was taking the class