Engineering and Technology Journal

The control of the group delay and group delay dispersion in the design of
chirped mirror is difficult. To reduce this difficult it is important to adopt what is
so called impedance matching design. This paper presents a design of quart wave
mirror which includes the impedance matching. The design is divided into two
stages. In the first stage a quarter waves stack to provide high reflectivity of
over a bandwidth of the design and within certain limits is considered.
The control on average group delay depends upon wavelengths that are function of
penetration depth. However, the group delay as a function of wavelength shows
periodic variations due to the impedance mismatch between the ambient medium
and the mirror surface and its layers. In the second stage of the design tapered
Bragg stack over a wavelength range (600-1100nm) is adopted as a single chirp

The petroleum refining industry is one of the largest users of distillation
technology. The crude distillation unit is one of the most important refinery operations
fractionating preheated crude oil into respective product fractions like Heavy Naphtha,
Kerosene, Aviation Fuel, Light Gas Oil, Heavy Gas Oil, Reduced Crude Oil, etc. It
uses heat supplied at higher temperature levels, and rejects almost equal amount of
heat in the condenser at lower temperature levels yielding a separation work of
mixtures. Therefore, it becomes important to study the energy and exergy of the crude
oil fractionation tower to analysis the energy efficiency.
The present study deals with a thermodynamics analysis, energy and exergy
efficiencies and the irreversibility rate for of the crude oil fractionation tower (AFT).
The results shows that the total irreversibility losses are 90.7 MW, 95% are
contributed by the AFT, and 5% by the furnace, for a flow rate of 159.2 kg/s of crude
oil processed. The energy efficiencies are 0.597 for the AFT, 1.0 for the furnace as we
are assuming adiabatic heat transfer in the process and 0.704 for the overall system.
The exergy efficiencies are 0.5867 for the AFT, 0.974 for the furnace and 0.638 for
the overall system. From the values of the energy efficiencies, exergy efficiencies, and
the irreversibility rate in spite of the decline of the fractionation unit equipments, it
shows that the operating conditions used (especially the temperature profile and the
pressure profile of the AFT and the flow rates of the different streams) gives the best
results.

The environmental site assessment (ESA) of Al-Duara refinery in Baghdad, Iraq.
The hydrocarbon content of the soil around this site was measured to evaluate the
extent of the organic pollution depending on selected parameters of potential
pollution. Soil samples were collected at various depths from almost all locations
including: production units, storage tanks, the landfill lagoons at the outside boarder
of the refinery and the residence location. For the evaluation of the nature of soil
layers, a monitoring well was drilled in the vicinity of a wide dumping area for heavy
untreatable materials. Some field tests were carried out to evaluate the hydrocarbonin-
soil (Turbidimetric); Laboratory analysis for the soil extracts and types of
hydrocarbon pollutants. The soil texture was evaluated using the standard methods to
assess any future remediation efforts. It appeared that storage tanks location is among
the serious polluting sources via leakage or overflow of the drainage collection
channels. The pollution sometimes extended deep in the soil, 80-100 cm. The
maintenance and rehabilitation operations contribute much pollution by heavy sludge
containing hydrocarbons, mud and inorganic matter. Most of the pollution load is
directed towards the wastewater treatment plant. The dumping location and over more
than 30 years resulted in deep penetration of hydrocarbons so that the location is
considered the most effective source of pollution. Finally, the fall out is a major
means of pollution of remote area within the site by heavy hydrocarbons.
Recommendations for remediation of the most polluted locations in the site were
listed at the end of this study. However, the company is continuously doing actions to
remove polluted soil and replace it with clean soil.

Recently, there has been great interest in the integration of distributed
generation units at the distribution level. This requires new analysis tools for
understanding system performance. Installing Distribution Generation (DG) in
the distribution level has positive impacts on the system voltage profile as well on
the substation’ s capacity. However the extent of such benefits depends greatly of
the DG size and location.
In this work, investigation of adding diesel units regarded as distributed
generators at the distribution voltage levels were done. These investigations dealt
with the impact of the units addition on the Iraqi grid power flow and short circuit
levels . This work is done by using PSS/E program (Power System Simulation for
Engineering), A sample from substations (with fuel and space availability ) of the
Baghdad area were considered for the diesel units addition , in order to find
recommendations for the voltage level to connect these units to it.
The extension in mind was to develop a quick rule of thumb in order to decide
where to add the DG units. This of course with no regard to the unit size as it is
limited by the Short Circuit Level (SCL) and economic considerations. IEEEstandard
systems were considered here with the development of Matlab routines
for the simulation and calculations required.
A novel quick criterion as where to add the distributed generation to minimize
loss was proved. This state’s “add the units at the lowest short circuit level bus,
i.e., at the bus of highest Thevenin impedance”.

This paper proposes the excitation system control of three phase
synchronous generator for improving the step response using an adaptive fuzzy
controller. The dynamic model and simulation of 3-phase synchronous generator
are proposed. The open loop voltage control responses under no-load and full-load
conditions are proposed too. The PI closed loop controller of excitation system is
illustrated as a conventional control method, which gives an acceptable operation
behavior of synchronous generator terminal voltage. An adaptive fuzzy inference
system is proposed in this paper as a close loop controller, which gives an ideal
performance in both of no-load and full-load conditions as compared with PI
controller to control the 3-phase synchronous generator excitation system.
Simulation results show the effectiveness of the proposed fuzzy controller schem. e
Which gives in fuzzy controller; rise time= 0.3 sec., overshot= 0%, settling time=
0.3 sec., and steady state error= 0%. Whereas, in PI controller; rise time= 0.55
sec., overshot= 20%, settling time= 2.8 sec., and steady state error= 0%.

Zinc oxide (ZnO) thin film have been prepared by Spray Pyrolysis technique using
zinc acetate dehydrate dissolved in methanol, ethanol and deionized water. A number of
techniques including X-ray diffraction (XRD), optical transmission microscope (OTM),
Fourier transform infrared (FTIR) spectroscopy, UV-visible were used to characterize and
study the obtained ZnO thin films. The evolution of preferred crystalline orientation in the
ZnO films was systematically investigated and the (002) reflection was the preferred
orientation. The optical measurement reveal that films have a maximum transmittance of
about 90% and a direct band gap of 3.2 eV.

A simplified lumped model that makes direct correlation between Rosen's
piezoelectric transformer (PT) dimensions and material properties via equivalent
circuit parameters was studied. The model calculation of the resonance
characteristics and voltage gain was associated with changes in operating
temperatures from 50°C to 70°C. It is found that for different load resistors, the
resonance frequencies are shifted by less than 1.6% their normal values upon
raising the operation temperature to 70°C, whereas the sensitivity of voltage gain
is better at higher load resistors.
Each of the elastic compliances SE
11, SE
33 and SD
33 of the PT material due to their
temperature dependency cause the resonance frequency to shift below and above
the normal value by less than 1% for very slight change in voltage gain in each
case. The overall balance between mechanical parameters may play role in the
optimum stability of the voltage gain.

Within the last decade, there has been a vast increase in the accumulation
and communication of digital computer data in both the private and public sectors.
Much of this information has a significant value, either directly or indirectly, which
requires protection. One of the most important protection methods is inventing and
developing different encryption algorithms. The algorithms uniquely define the
mathematical steps required to transform data into a cryptographic cipher and also
to transform the cipher back to the original form.
This paper introduces a new method to enhance the performance of the
Data Encryption Standard (DES) algorithm. This is done by replacing the
predefined XOR operation applied during the 16 round of the standard algorithm
by a new operation depends on using two keys, each key consists of a combination
of 4 states (0, 1, 2, 3) instead of the ordinary 2 state key (0, 1). This replacement
adds a new level of protection strength and more robustness to breaking methods

Permanent Magnet Brushless DC (PMBLDC) motors are one of the electrical
drives that are rapidly gaining popularity, due to their high efficiency, good dynamic
response, high mechanical power density, simplicity, cost effectiveness and low
maintenance.
In this paper, the state-space technique is presented and used for analyzing the
dynamic performance of PMBLDC motor. The method is based on the formulation of
state equations from the mathematical model of the motor and conversion of them into
a set of linear algebraic equations by the use of trapezoidal rule of integration. The
simulation of the motor has been done using the software package Matlab

The main purpose of this paper lies briefly in submitting least square
method for solving linear delay Volterra integro differential equation of the
second kind containing three types (Retarded,Neutral and mixed)with the aid
Bernstein polynomials as basis functions to compute the approximated
solutions of delay volterra intgro differential equations .Three examples are
given for determining the results of this method.

A preparation of poly (vinyl alcohol) (PVA)/alumina (Al 2O3) gel
composite was investigated.
This type of composite gel was carried out with two stages firstly the
hydrolysis of polyvinyl alcohol in a hot water at 200ºC for 2 hours and different
mixing ratio of (PVA/H2O) solution at (10,20,30,40,50) wt% has been
investigated to check its operating conditions .Secondly different ratios of alumina
refractory were used (5,10,15,20,25) wt% of (AL2O3 /PVA) at 350ºC for 4 hours
to give a completes composite gel of ( PVA/Al2O3) in a polymerization stage.
The final composite gel of (Al2O3/PVA) is molded in a different shapes
and size due to suitable characteristics tests in order to check chemical, thermal,
and mechanical properties afterward curing these specimens at 120ºCfor 2 hours
to complete the compatibility of composite gel.
The results tests proved that: All final composite gel specimen is more
efficient than other base polyvinyl alcohol (PVA) of high mechanical and thermal
properties than base one with less internal stresses, also the resistance for chemical
solutions in (100%H2O, 10%H2SO4) is increased at sever conditions at 50ºC for
5 days especially for optimum mixing ratio specimen No.3 with preference for
optimum sample No.3 of (30%PVA Sol./15% Al2O3) g/g.

An Ellipsometric experimental set up of SOPRA ES4G type with a powerful
WVASE software for the theoretical calculus of the Ellipsometry parameters. The
Ellipsometry Technique can determine amplitude and phase information Ψ( and Δ)
dependent on wavelength range 250 nm to 900 nm (1.5 - 5 eV), including original
practical solutions, were developed. Encouraging results of TiO2 were obtained in
applying the simple Ellipsometric method of azimuths to determine the optical
constants for TiO2 with this optoelectronic device

In this work, the peak modal gain and the radiative and Nonradiative
current densities for Single Quantum Well (SQW) GaAs/AlGaAs laser are studied
theoretically with varying the well widths Lz=(200, 150, 100, and 75) Ǻ, at a
bandgap discontinuity ΔEc of 0.1 eV, it was found that the highest value of the
peak modal gain gmax=400 cm-1 is achieved at Lz=75 Ǻ, and the lower value to
achieve transparency Ntr=0.5×1018 cm-3 at Lz=200 Ǻ .
The optimum value for QW width to achieve the lower threshold current
density Jth=481.5 A/cm2 at the same injected carrier density is Lz=100 Ǻ.

The oral administration of the aqueous extract of Teucrium polium to a
mature male mice in daily oral doses of 50 mg/kg body weight (group II) and 100
mg/kg body weight (group III) for eight consecutive weeks were resulted in
significant increase (P<0.05) in the testicular weight in the treated groups in
comparison with control. The aqueous extract affected the spermatogenesis which
demonstrated by an increase in leydig cell, spermatogonia, spermatocytes and
spermatozoa. The hormonal profile was influenced by the aqueous extract. The
testosterone level was significantly increased (P<0.05) in the treated groups, but
no significant differences (P>0.05) in urea and uric acid levels between control
and the treated groups were shown. The kidneys of the group III were affected and
showed degenerative changes and necrosis in nucleolus of cell of tubules and there
is destruction in glumerular by increscent of mesenchymal cells

Removal of heavy metals from wastewater is of primary importance
because they are not only causing contamination of water bodies but are also toxic
to many life forms. One potential application of ion flotation is to treat large
volumes of dilute aqueous waste solutions contaminated by heavy metals ions.
Cupric ions have been removed from dilute aqueous solutions, in acidic conditions,
using MULTI-STAGE LOOP FLOTATION (MSTLFLO) column. The column
consists of three stages of 70 cm long and 10 cm outside diameter. The total height
of the column is 2.25 m. Three draft tubes are used inside the column each of 50
cm long. The results indicated that MSTLFLO is an effective process for the
removal of Cu+2 ions from aqueous solutions. As high as 94% of the cupric ions
were removed at air superficial velocity of 2.3 cm/s (equivalent to air rate of 50
l/min.) and 20ppm frother concentration in the presence of sodium dodecyl sulfate
(SDS) as a collector. An empirical correlation representing the relationship
between the overall removal efficiency, the superficial air velocity and the
concentration of the frother was proposed.

The main purpose of this work is to propose the parameterization techniques for
solving quadratic optimal control (OC) problem with aid of both Chebyshev and
Hermite Polynomials as a basis function to find the approximate solution for OC
problem. Some examples are given as applications of the proposed

The main purpose of this work is to devote B.spline with two variables
as basis functions to find approximate solution of Multi dimensional delay
fredholm integro partial differential equations .Three numerical examples are
given for determining the results of this method

Data collection using traditional methods for detecting and mapping
subsurface features can be need more time consuming and costly. Beside that the
geological research project and Job cost estimating require accurate information
about subsurface condition. Ground Penetrating Radar (GPR) can map and detect
bedrock, buried objects (pipes, cables, etc), water table, soil profile, faults, voids
and sinkholes quickly, easily, accurately, and cost effectively. The accurate
location of buried utilities is imperative for contractors. Hitting a high voltage
power line or water main con be dangerous, disruptive to citizens, as well as
expensive.
The main objective of this research is to introduce utility of using GPR in
locate features such as buried tanks and pipes, locating underground pipes for
efficient pipes system management and for avoiding damage during excavation
have become a relevant issue in metropolitan areas.
Gathering data inside the boundary of the University of Technology with
the area approximately equal to (4320 m2), data processing using RAD
EXPLORAR software with the helping of Geographic Information System (GIS)
and Global Positioning System (GPS) to produce a GIS map have been carried
out. The discussion of the result is included with the basic recommendation

An approach for low cost uniform and octave filter banks for Audio applications
is proposed. The analysis stages of these filterbanks are based on IIR allpass second
order sections with modified response. The modification is performed by forcing
phase non-linearity at the analysis stage to be out of region of interest. By
oversampling, the non-linear segments near the band edges are removed through
subsequent synthesis filtering. Compared to existing literature designs, the new
approach offers a substantial lowering in computational power, and a lower
input/output delay.The simulation and testing of this technique was performed using
MATLAB software package

The object of this research is to study the passivity of surfaces of heat
treated medium carbon steel (CK45) by annealing, spheroidise annealing,
normalising, and water hardening. This research also studies corrosion resistance of
corrosion protected samples by passivity in the industrial atmospheres for two
periods (720 hr. and 1440 hr.).
The results, which have been obtained, show that the corrosion rates in the
unprotected samples are high compared with the corrosion protected samples by
passivity.