Engineering and Technology Journal

This study was conducted to determine the land cover changes between year 1976
and year 2011 in Karbala Governorate by using an integrated approach of remote
sensing data and GIS applications for investigation of the spatial and temporal
changes. A part of Karbala Governorate, whose Area is 768 km2 was selected as study
area.
Four cloud free Landsat MSS, TM, ETM+, and SPOT scenes covering the study
area were selected for analysis. Images were acquired in years 1976, 1990, 2001, and
2011 respectively. All images which mentioned above are rectified and registered in
Universal Transverse Mercator (UTM) projection zone 38 N and supervised image
classification system has been observed to classify the images in different land cover
categories. Six land cover classes have been identified and used to determine the
change in land cover in study area and these classes are: Agricultural land, Water
bodies, Urban Area, Sand dunes, Bare soil, and Waterlogged Area. According to the
results obtained from statistics of classification, it was observed that most changes
occurred in heterogeneous agricultural areas. It is thought that the main reasons of this
change are increasing population pressure, increasing sand dunes, appearance and
increasing waterlogged area and changing economic activities. Those reasons have
been led to the decrease of the agricultural areas in study area during period from year
2001 to 2011.

This research serves as basis to investigate the total energy losses in DC-DC
converter circuit. The circuit used for the investigation was the inductive load
chopper circuit .Two diodes were used one is the Silicon PiN diode (8A/600V) the
other is Silicon Carbide Schottky diode (6A/600V).The waveforms of current and
voltage diode under test ( DUT) and IGBT are measured respectively and
compared them with the simulation results. The gate resistance G R was also
changed to further investigate the effect of di/dt of the DUT current during turnon
of the switch on the total energy losses in the system.

In modern power system utilities, increased power demand often lead to the
situation where the system no longer remains in secure operating region. Flexible AC
Transmission Systems (FACTS) controllers can play an important roll in power
system security enhancement. The goal of FACTS devices study is to measure their
impact on the state of the electrical networks into which they are introduced. Their
principal function is to improve the static and dynamic properties of the electrical
networks and that by increasing the margins of static and dynamic stability. In this
paper the modeling of Static Synchronous Compensator (STATCOM) within
Newton-Raphson power flow equations has been presented, discussed, implemented
and the transient stability of a power system was tested when three phase fault is
applied at a certain branch of the power system. Case studies are carried out on a 5-
bus and a 30-bus test systems to demonstrate the effectiveness of the proposed model.

Iraqi Marshlands which are located within the southern part of Iraq were dried
after 1991. The dried marshes were re-flooded after year 2003. Because of the
shortage of water that feeds the marshes during the last years, these marshes began
to dry again. Therefore, finding new feeding sources became very necessary matter.
The Main Outfall Drain, MOD, is suggested to be one of these sources to feed Al
Hammar Marsh during the dry water years. Ad Dalmaj Lake which is located
upstream of Al Hammar Marsh is mainly feeding by the MOD water and then the
outfall of this lake is discharge again into the MOD. Therefore, the hydrological
operation of this lake and then the quantity and quality of the outflow water from
this lake into the MOD affected the water quality of Al Hammar Marsh when using
the MOD water to feed the marsh.
A hydrological and water quality routing model was prepared based on mass
conservation low, mass balance model, and two scenarios were applied for Ad
Dalmaj Lake feeding, constant inflow with variable outflow and constant outflow
with variable inflow, based on the incoming and outgoing discharges. Each
scenario includes six cases of lake maximum inundation area; 100%, 90%, 80%,
70%, 60% and minimum inundation. For each case the inundation area varied with
respect to the ET0 variation from minimum area during the month of maximum ET0
to maximum area, of this case, during the month of minimum ET0. TDS
concentration was used as a measure of the salinity of the water because it fairly
indicates the level of salinity problem. The variation of inflow and outflows
discharges, water level, lake and marsh area, storage volume, and the water salinity
within the lake and marsh were
Results of applying these models with these flow scenarios and inundation
cases show that the water salinity within Ad Dalmaj Lake and Al Hammar Marsh
was out of the acceptable range of international standards for most of the studied
cases. While for other cases it was unpalatable for drinking, several restrictions
must be imposed when used for irrigation to prevent salts effects on crops, soil, and
ground water, and not acceptable for livestock and unfit for poultry in most of the

This study deals with assessing the effect of stress level on bearing capacity
factor , distribution of shear stresses at soil-pile interface along pile shaft, and
presence of critical depth concept for bored piles axially loaded in compression and
embedded in dense sand. These investigations are made using finite element method
with the employment of a wide range of stresses by using piles with dimensions
starting from laboratory dimensions and goes towards field dimensions with
embedment ratio range from (15-40). The soil and the interface behavior is
modeled using Duncan-Chang hyperbolic soil model with empirical equations
account for reduction of angle of internal friction ø with increasing in stress level.
Bored pile is modeled as a linear elastic material. The results showed a dramatic
decrease in bearing capacity factor as length of pile increase. It was also found
that the embedment ratio has a significant effect in increasing bearing capacity
factor , and the distribution of shear stresses at soil-pile interface is not linear and
does not tend to take a constant value beyond a certain depth of pile nor decreases
after a certain depth along pile shaft. The fallacy of critical depth also noticed and
discussed in this paper

Experimental investigations have been carried out to study the performance of
trickle bed reactor. The effect of key parameters that play predominate role in the
performance of trickle bed reactor was studied. A laboratory unit was constructed
for this purpose where a versatile reactor setup required " high pressure stainless
steel reactor of 0.05m i.d × 1.25m height", in which the hydrodynamic
experiments carried out under different operating condition namely, superficial gas
velocity and liquid velocity , reactor pressure, bed temperature .Air–water system
was used for hydrodynamic experiments pressure drop, dynamic liquid holdup, and
axial dispersion coefficients were estimated. The results also show that the
dynamic liquid holdup increases with increasing liquid velocity and decreases
with increasing superficial gas velocity and bed temperature. Axial dispersion
tends to increase with increasing superficial gas and liquid velocities while it
decreases with increasing bed temperature.

Micro -EDM is one of an important method in machining holes which is used in wide
applications to fabricate medical devices and small dies. This work study the process of
producing micro holes for copper alloy workpieces using, stainless steel electrode
and dielectric solution (tap water), using DC current and low voltage (70V) to cut
(0.7mm) thickness of copper (Cu) alloy workpieces in order to obtain the micro holes.
This work included an experimental work for electrical discharge machining
(EDM) to produce micro holes with different diameters (400, 300, 210, 200, 120,
100, 85, 75, 70) μm.
The objective of this work is to obtain an optimal setting of EDM parameters to
produce micro holes in copper alloy to achieve the optimal values of required holes
diameters.
A regression model has been developed to represent this process. An approach
has been made to optimize the process parameters (current, gap distance, machining
time) using ANOVA analysis. This analysis was performed to obtain the most
significant factors influencing the production of micro holes.

This research involves study corrosion of low carbon steel under static and flow
conditions at 200L/h in the absence and presence of CO2 at two rates 9 and 30 ml/min
at four temperatures by electrochemical method using potentiostat. Numerical model
was achieved to compare between the experimental and theoretical results to estimate
corrosion rate. The results show that the presence of CO2 under static conditions
shifts the Ecorr toward noble direction, while under flow condition the presence of CO2
shift Ecorr toward active or noble direction at two rates of gas. The data of corrosion
rate in mm/y indicate that the presence of CO2 with two flow rate increased the rate
compared with the case of absence of CO2 under static conditions except one case,
while under flow conditions, the presence of 9 ml/min. CO2 increases the corrosion
rate, while the presence of 30 ml/min. CO2 decreases the rate because of formation
FeCO3 scale except at 298K. A Mathematical model was done which show the
volumetric flow rate of CO2 and finally the corrosion rate of CO2 correlated with
dimensionless groups and independent parameters.

In the present study, traditional and hybrid composites were prepared by Hand lay-up
molding and investigated. The composites constituents were unsaturated polyester resin
as the matrix, 3% and 6% volume fractions of carbon fibers as reinforcement and 3% of
Al2O3, Al, Cement and local Gypsum (calcium sulfate anhydrate CaSO4) as filler
particles. The investigated physical properties were density, porosity while the
mechanical properties were tensile properties, bending modulus of elasticity. The
experimental results showed that increased volume fraction of carbon fibers to (6%) led
to increase in physical properties (density, porosity. As for the mechanical properties,
carbon fiber composites and (3% carbon fibers/Al2O3)-contained hybrid composites gave
the higher tensile and fracture strength, carbon fiber then gypsum composites gave the
higher bending modulus.

In this research the mechanical properties of PMMA polymer reinforced by
ceramic particles (silica) has been investigated. Many tests are performed on these
composites. The effects of the particles size and volume fraction on the mechanical
properties which include: ultimate tensile strength, elongation percentage, modulus
of elasticity, bending modulus, flexural strength, max. shear stress, impact strength
and fracture toughness were studied.
Statistical and mathematical analyses were used to the processing of the
experimental data. Mathematical models were done which show the mechanical
properties of composite materials as a function of particles size and volume
fraction.
The results had revealed that the values of modulus of elasticity, elongation
percentage, tensile strength, bending modulus and max. shear stress increase with
the addition of SiO2 particles and with the increase of the volume fraction of them
and its reach the maximum value at (12% vol.) and (25 m) particles size. The
values of fracture toughness and impact energy decrease with increase of volume
fraction. Silica particles with small particles size improved these properties more
than that of large particles size.

This work aims to find forming limit diagram and mechanical properties
experimentally to measure formability by hydraulic bulge test and tensile test, and
determination the values of the bursting pressure and final thickness in the final
stage at bursting experimentally and numerically by using program (ANSYS 11) to
perform numerical simulation for copper and aluminum alloy (6060) tubes before
and after heat treatment by hydraulic bulge test.
In this work, used two types of tubes with dimensions for copper of
(L0=150mm, d0 = 41.275mm, t0 = 1.06mm) and for aluminum alloy (6060) are
(L0=150mm, d0 = 60mm, t0 = 2 mm). Applied heat treatment (annealing) of copper
and aluminum tubes at temperature (450°C, 400°C).the holding time in the furnace
was 1 hour and then cooled in the furnace. Has been printed square grid by screen
method with dimensions (5x5 mm) for copper and aluminum tubes before and after
heat treatment and with dimensions (2.5x2.5 mm) for tensile samples of copper and
aluminum before and after heat treatment. Strain Measurement accomplished by
using image processing technology using MATLAB by measuring the dimensions
of the grid printed before and after the deformation and then measure the true strain
on tensile samples and tubes used in the tensile test and hydraulic bulge test before
and after heat treatment.
The results show that, the values of the bursting pressure and final thickness in
the final stage at bursting for copper tube before and after treatment is (29MPa,
27MPa(،) 0.892mm, 0.621 mm) and for aluminum tube before and after treatment
is (19MPa, 16MPa),( 1.789mm, 1.4872 mm). Increasing formability and
decreasing bursting pressure of tubes after heat treatment of increasing the strain
hardening exponent (n) of tubes.

The swelling /shrinkage are complex phenomenon in the steam power plants.
One of the important reasons is the chemical effects, which causes a bubble
formation and hence serious foaming carryover problems in the boiler. The present
work is devoted to study and measure the chemical effects of the swelling and
shrinkage phenomena due to the disturbance of the variables in the drum boiler of
steam generation unit. The problem was studied and analyzed to find a suitable
solution to reduce the foaming carryover, and hence to control the swelling and
shrinkage phenomena. The theoretical part is describing the mathematical model
for the boiler variables. The drum pressure and drum level at different load
demands of boiler were measured experimentally. The feed water was treated
carefully in order to study the reduction of foam produced from a small amount of
lubricant oil in the boiler water. The foam was treated using silicon antifoam [SN
6010]. The experimental results proved that the silicon antifoam is efficient to
remove the foam completely and then reduce the disturbance in the pressure by
18.6% and the reduction in swelling and shrinkage was by 29.4%, and 16%
respectively.

The structural behavior of three steel plate girders under shear is studied. The first
one is the reference plate girder (G) which is prepared without web openings, and the
second one (GO) is fabricated to contain circular opening at the center of each web panel,
the diameter of the opening is 60% of the web depth, while the third plate girder (GOR)
is with reinforced strip welded around the circular web openings. The aspect ratio of the
panels is one and they all have the same dimensions. The experimental results obtained
from second and third plate girders have been compared with those obtained from the
reference plate girder. The comparison indicates that the reduction in the ultimate shear
load for plate girder with web opening is 51% and for the plate girder with reinforced
web opening is 35%. Also through the experimental results, new formulas are presented
to predict the ultimate shear load of perforated steel girders with large openings.
A nonlinear finite element analysis is carried out for the tested plate girders using the
package software program (ANSYS V.11). The analytical results contain the ultimate
shear capacity and Von Mises stress distribution. The results of finite element models are
compared with results of experimental tests. The difference in ultimate shear load was
10%, 9% and 1.5% for plate girders GO, GOR and G, respectively. Also a parametric
study with varying size of the reinforcement around the web openings is performed by
using the ANSYS program, and it is found that the thickness of the reinforcement strip
has higher effect than its width on the ultimate shear capacity of perforated plate girder.

Many previous studies dealt with the concept of transparency in architecture has
emerged importance of the formal and moralaspects in achieving the concept of
transparency, also focused on each concept detailed, varied in adopting the concept
as afeature design lead and certain functions and on this basis was established trend
has pursued research to study the concept of transparency in contemporary
architectural production. The research problemrepresented by (there is a lack of
knowledge about the concept of transparency as articulationfeature in
contemporary architecturaloutput), the objective of this research isrepresented by
clarify the most important characteristics of the transparencyconcept as
articulationfeature in contemporary architectureoutput. The research adopted a
method to achieve the objective and reached to the conclusions and
recommendations.

This research involve with creating a program in basic language after modulating
the equations which describes the coordinates of any point lays on the involute
curvature. With the aid of a subroutine program, the main program transmits the
resultant data to a "dxf" file in order to be useful in using with any package under
AutoCAD. After that it's easy to get a precise drawing for the involute of the gear
under concern. The resulting drawing can be used to produce the deferent types of
gears tools