Engineering and Technology Journal

The present study investigated the possibility of enhancing collapsible gypseous
soil of Al-Qarma site (with relatively high gypsum content around 50%), which is
located in Al-Anbar Governorate, using kaolinite and bentonite as additives. The
essential idea is concentrated in mixing these additives with natural soil using
different percentages (5, 10, 15 and 20% by soil dry weight) to investigate soil
shear strength enhancement. The effect of such additives on soil shear strength
parameters, cohesion (C) and angle of internal friction (Φ), and their behavior were
studied using direct shear test. The results showed that shear strength parameters of
soil sometimes increased and then decreased with increasing additives. Generally,
higher shear strength parameters have been obtained from bentonite mixed soil
than that of kaolinite mixed soil for the same percentages of additives. It was
concluded that bentonite was much more effective in increasing C and reducing Φ
than kaolinite. While, kaolinite was much more effective in reducing C than
bentonite. It was also concluded that gypseous soil shear strength is improved
using such additives (with only 5% kaolinite or with only 20% bentonite) which
provide cohesion strength to the soil mass and also acts as a binder agent material

One of the major issues in the dynamic analysis of soil-structure interaction
problems is to model the far field medium. The dynamic analysis of soil-structure
interaction problems can be carried out by using a numerical solution procedure
such as finite element method. For domains of infinite extension of the soil, using
of the standard finite elements method leads to spurious reflections for waves on
the artificial boundaries which can seriously affect the results.
This research presents a method based on the mathematical representation of
wave propagation to analyze the problems in dynamic soil-structure interaction. In
this method, the infinite medium (unbounded domain) of the soil is represented by
viscous elements to simulate the radiation damping in the soil. In addition, the
material damping of soil is represented by Rayleigh damping and implemented in
the bounded domain.
The results obtained from this study indicated that, dissipation in the energy of
wave occur due to representing of the infinite medium of the soil by viscous
elements and Rayleigh damping. By comparing the results with those obtained
from the boundary elements method to simulate the infinite extension of the soil
which is proposed by Estorff and Kausel (1989), a good agreement is achieved. In
addition, the dynamic response at any depth under the foundation can be estimated
by using the present method

The study investigates the effects of salt concentration on some mechanical
properties of thermoset polyester resin without reinforce and polyester resin
reinforced with random fiber glass mat. The volume fraction of the composite
material varies in (15%, 25%, 35% and 45%). The two types of material were
immersed for (40) days in different salt concentrations ratio (15%, 35% and 55%).
The environment consists of salt 99.9% and 0.008% magnesium carbonate and
potassium iodide. The study depends on the experimental results of impact test and
tensile test to describe the mechanical properties of polyester resin and composite
material. It is found that the fracture toughness of composite material increases at
approximate ratio of (2.9%) while the polyester resin increases at approximate of
(2.25%) due to increasing the salt concentration in water with ratio (40%), so that
the fracture toughness increases with approximate ratio (3%) due to increase in the
volume fraction ratio from (15%) to (45%). The elastic modulus of composite
material increases with ratio of (14.9%) and (90.29%) for polyester due to increase
in the salt concentration ratio in the water at approximate ratio of (40%).
The elastic modulus increases at ratio of (13.73%) , the yield stress of polyester
increase at ratio (50.32%) and yield stress of composite material increases at ratio
(55%) as a results of increase in the volume fraction ratio from (15%) to (45%).

This paper compares between responses of Fuzzy Logic Controller (FLC) based
exciter and auto-tuning FLC based exciter. Both of the exciters are simulated
separately with synchronous generator connected to infinite bus through a short
transmission line. The systems where subjected to three phase fault at the infinite
bus, maximum Integral of Square Error (ISE) of generator terminal voltage
response and critical clearing time were taken as performance indices of the
exciters. The systems then studied under normal operating condition to justify the
need of auto-tuning

This Study is aimed to present a simplified approach enable to construction of a
new design charts for hollow section reinforced concrete columns subjected to an
axial compressive load and uniaxial bending. These design charts can be used
directly in the analysis and design of hollow section columns. These charts can be
used in design to determine the required amount of steel reinforcing in addition to
the required column dimensions, while in the analysis by using these charts; the
column load capacity can be estimated.
Two design examples are given to explain the use of the new design charts. It
has been shown by these examples that the new proposed charts are very simple to
use in structural design applications.

In this study, the removal of Ni (II) and Cd (II) ions from aqueous solutions using
the adsorption process onto synthetic Zeolite has been investigated as a function of
initial metal concentration, contact time, pH and temperature. In order to find out the
effect of temperature on adsorption, the experiments were conducted at 20, 30, 40, 50
°C and 15, 30, 50 °C for Ni (II) and Cd (II) respectively. Kinetics data show that at
higher temperatures, the rate of adsorption on the synthetic Zeolite is much higher
compared to that on the lower temperatures. The optimum pH for Ni (II) and Cd (II)
removal is found out to be 5.5 and 6 respectively. The batch method has been
employed using initial metal concentrations in solution ranging from 25 to 100 mg/l
for Ni (II) and from 10 to 25 for Cd (II) at optimum pH. An Atomic Absorption
Spectrophotometer was used for measuring the heavy metal concentrations before and
after adsorption. Langmuir, Freundlich, models were applied to adsorption equilibrium
data to find the best amongst these models. This study has demonstrated that Zeolite
was capable to remove 90% of nickel and cadmium from solution of different
concentrations. This implies that Zeolite is an important in the removal process. These
capabilities of Zeolite could lead to development of a viable and cost effective
technology for removal of these pollutants from wastewater for countries like Iraq

An experimental study on the effect of filter types, relative humidity and using two stage
filters on the weight efficiency and pressure drop across the filter was carried out, to
complete the study a test rig is designed and built, the rig consist of three sections air duct,
of 30 cm ×30 cm cross sectional area, with overall length of 220 cm. Six types of air filters
are used in a single stage filters; namely spongy, polyester, synthetic one and two layer
aluminum filters. A molten Aluminum powder dust (Type Aluxite No. 25, 98% less than
35 microns and 2% less than 10 microns) is used. In two stage filters study the bag filter is
used as a secondary filter while the primary can be any type of the five filters mentioned
above. The study shows that the spongy filters gives a maximum efficiency when is used as
a single stage filter as compared with the other filters type. Increasing of working
environment relative humidity improves the weight efficiency for both single and two stage
filters. Two stage filters can improved the filtration process, it is found that the combination
of spongy filter and bag filters give a maximum of weight efficiency of about 92% when
the relative humidity equals to 90% . Space distance between two stage filters affect the
weight efficiency, it is found that the best distance between the spongy filter and bag filter
is between 15 to 20 cm.

Knee ankle foot orthoses (KAFOs) are prescribed to paraplegic patients with
low level spinal cord injury and with good control of the trunk muscles. Three
types of KAFOs were used in this work (plastic-metal, metal-metal and composite
materials), the composite materials were depended on the number of perlon layers
(13 layers & 9 layers) with one layer of carbon-fiber and (6 layers) without carbonfiber.
The mechanical properties of most of the KAFOs’ materials were tested by
tensile test and fatigue machines.
The data of gait cycle (Ground Reaction Force (GRF), and pressure distribution)
were collected from one patient with poliomyelitis (wearing brace type KAFO) and
one normal subject. In this paper, the FEM (ANSYS) was used to compute the
safety factor of fatigue for all types of KAFOs’ models and the equivalent stress
(Von-Mises). The interface pressure between the patient’s leg and the brace was
tested by using a piezoelectric sensor.
The results obtained from ANSYS gave the profile of safety factor of fatigue,
for metal-metal KAFO (3.69), plastic-metal model (0.88). While, the (13) layers
for composite material was about (1.4), but (1.07) & (0.41) for (9) layers and (6)
layers, respectively. The value of safety factor increased with the composite
material for the suggested design.

Failure of plain concrete in tension is characterized by softening, which is
accompanied by the development of regions of highly localized strains. The main
objective of this research is to study the fracture energy (the value of tensile strain)
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in the concrete and its effects on the load for plain concrete beams. Beams
were tested by Bosco and analysis by the use of computer program ANSYS. The
three dimensional brick element was used to represent the concrete element.
The results confirmed that the plain concrete beams do not fail when the first
crack is obtain, but depends on the value of the tensile strain ????????????
(fracture
energy), where the increase in the value of the tensile strain due to increases in the
load applied on the beam

The water quality index (WQI) is a very effective method that allows to
compare the quality of various water samples based on the indicator values of each
sample. In this study, water quality index for Basrah water supply was determined
by choosing nineteen water treatment plant (WTP) in Basrah city. Twelve chemical
and physical parameters of each WTP were analyzed for one year during 2011.
The results show that the WQI values of water supply in Basrah city are ranged
from 83 to 275. About 10% of water supply can be classified as a good water, 74%
can be classified as a poor water and the remaining 16% are very poor water. The
prime cause of deterioration in Basrah water quality is the poor quality of the raw
source water represented by Shatt al-Arab river, due to the large amount of
contaminants are discharged in it. In addition, it is affected by the tide
phenomenon of Arab Gulf which causes increase of salts concentrations. Also, the
WTPs in Basrah city are conventional type that do not deal with soluble elements.
These plants need upgrading by adding filter membranes or ion exchange units, to
produce safe water for human consumption.

The purpose of this study is to investigate the kinematics in humans during stair
climbing and the influence of stair slope variation on gait cycle .The analysis of
biomechanical aspect involved in stair ascent and descent can add to our
understanding of the diverse and complicated processes involved in human
locomotion and also be useful in the design of private and public environments
where stairs are employed. Another application is in the field of gait rehabilitation.
A comprehensive movement analysis of stair climbing can support the evaluation of
joint replacement or prostheses development. A staircase was developed and
designed that allowed the collection of kinematic data for multiple steps at different
staircase inclinations. All components are characterized by a robust design which
minimizes vibrations. Subjects ascended and descended a four-step staircase at three
different inclinations (24°, 30°, and 42°). Kinematics was analyzed by a camerabased
optoelectronic system. The data were further processed using kinovea and
origin pro.8.5 softwares. Hip, knee and ankle kinematics in sagittal plane during
stair ascent and descent were reported. Temporal gait cycle parameters were
significantly affected by staircase inclination but Joint angles showed a relatively
low but significant dependency on the inclination. This study presents a normative
database, which could be used as reference data for assessment of stair locomotion.

The exchange of the data between the drawing programs like this one used in this
research, AutoCAD, and the other application programs is very important to develop the
applications in CAD systems. The present paper aims to make a logic sequence for the
entities that are drawn randomly to prepare them to further CAD or CAM manipulations.
The methodology in this work is using the DXF (Data Exchange File) which represents a
CAD file format in which the drawing is saved by using AutoCAD package. All the
required manipulations, begging from extraction the data of the drawing entities to
accomplishment the sequencing, have been done by building a suitable visual basic
program. Also, the AutoCAD package has been used as a checking tool for the results
after applying the proposed program, by opening the new DXF file format to AutoCAD
environment. The results show that the use of the concept of exchanging the data in CAD
environment is a good way to apply the methodology of the research.

This research presents the theoretical model, simulation and experimental
verification to predict the magnitude of scallop height using 3 and 5-axis milling
machine, where the effect of geometrical shape of the workpiece relative to the effect
of geometrical shape of the tools had been studied, taking into consideration three
different types of milling tools (Ball, Flat and Torus) corresponding to the type of
machines that had been used to calculate the scallop height (h) in each point. Also, four
different types of surfaces shape (Horizontal, Concave, Inclined and Convex) surface
had been utilized to study the effect of these shapes on the value of scallop height.
Besides, the effect of cutting direction in each plane had been studied in both types of
milling operation (three and five axis milling machine). Finally, the value of stepover
had been changed so as to acquaint the effect of this parameter on the magnitude of
scallop height on both types of milling operation.
It was established that the scallop height is most influenced by the step over, cutting
direction, geometrical shape of the cutter and inclination angle of the plane. The results
also show that in 5-axis machining by utilizing different cutters, the angle of
inclination of the tool axis was most affects the value of scallop height. It was also
concluded that Torus cutter is better than other two cutters (Ball and Flat end mill
cutters).

The use of three dimensional computer graphics and visualization techniques is
becoming more and more popular, because these techniques visualize more
realistic object models than graphic based object models. However, in most
application of 3D modeling and visualization, large and complex 3D models data
are required. The basic data source of 3D modeling of regular or irregular surfaced
objects are known (or calculated) point coordinates. Obtaining 3D model of the
irregular surfaced objects need plenty of points to represent the surface exactly.
These points can be easily obtained both traditionnal methods and from the
measurement of the photographs. the production of 3D object in cloud points
dependind on the sampling rate and taking many captures. In this case, an object of
face-shaped clay was used and a 3D object is performed with (5563) 3D points
with sampling rate (1 mm). The smaller sampling rate results in longer processing
and more points. This case could be beneficial in documentation of cultural and
historical heritage in a digital library in observing the variation with time

Iraqi marshes are one of the most important biodiversity in the world. They had
many problems: bad environmental conditions, as well as decreasing of the amount
of water that reaches marshes after restoration, in addition to the increase in the
source of pollution around the marshes as a result of villages, hospitals, factories
….etc. All these reasons cause dispersion of pollutants in the marshes. This
research study the source of pollution such as ( industrial, agricultural, medical,
political and waste water) in Nassiriya marshes and project them on the digital
maps to generate a final map represents all the sources of pollutants in this region.
The research shows the environmental and medical effects of this pollutants and
comprising them with the Iraqi environmental legislations.