Engineering and Technology Journal

This research is concerned in showing the importance of material selection in
production design stage, the factors that involved the material selection strategies and
its criteria and the modern approach of materials selection since there are many
techniques of material selection. The proposal work helps in choosing the following
appropriate techniques from many quantitative ones. The following techniques
(Geometrical approach, Algebraic Approach), were included in the work the
developed system solves the selection techniques and introduce the best material from
a database contains the steel family.
The case study was examined from the real world of manufacturing and
satisfactory results were obtained. The developed algorithm is being to build Material
Selection Techniques system called MASTECH which incorporates making decision
on materials selection.
In the research, MASTECH system has been developed to aid both designers
and manufacturing engineers in choosing the most suitable material.

The objective aim of this paper is to develop an algorithm that generate NC tool
path for parametric surfaces based on the accuracy of a desired surface. A designed
surface is represented by sufficient control points , using these control points , the
surface has been represented depending on Bezier technique to generate reliable and
near-optimal tool path as well as cutter location data file for post-processing; the
proposed algorithm include two functions:
· Forward step function that determine the maximum distance between cutter
contact points (CC) with the given surface tolerance.
· Side step function which determine the maximum distance between two
adjacent tool paths with a given scallop height.
The output of these two functions are engaged with the generated interior data of the
desired surface and feed automatically to a vertical CNC machine (Bridge Port) through
the serial port (RS232), then one tool paths has been implemented for manufacturing one
parametric surface, with tolerance of 0.5mm, using vertical CNC milling machines
(Bridge Port) with ball nose end mill cutter ø 14mm.
The proposed algorithm has been implemented for tool path generation of several
parametric surfaces to illustrate its flexibility,

In this study, we have studied the entangled photon source and how the coincident
count rate and visibility could be affected by the optical elements of the system setup. The
profile of the interference dip of the optical elements for Quantum Cryptography (QC)
system is modified by the increase of the second order dispersion parameter (Dp) and lead to
increase of visibility. Non zero chirp parameter (ai) of the pump beam can provide a higher
central peak but on the other hand it reduces the visibility, the peak remains, while the
dispersion in an optical element through which down converted photon propagate leads to
asymmetry in the interference pattern dip , the dip is particularly stretched with larger value
of birefringent material length (20-30)mm. The highest visibility at birefringent material
dispersion (d) equals to zero, and the dip was broader at larger value of (d).

In this work, the porous silicon was prepared by using stain etching in HF-HNO3 at
different etching times. Then Rapid Thermal Oxidation (RTO) processes were used for
surface treatment at different temperature and oxidation time to enhancement sample
properties. Fourier Transforms infrared (FTIR) spectrum exhibit the formation of SiHx
(x=1, 2) and Si-O bonds which indicate the present of porous structure and formation of
oxidation porous layer. The Capacitance – Voltage characteristics reveal that effective
carrier density is 36*1015 cm-3 for sample etching time at 2min, while there was a
change from (37.8*1015 to 45.7*1015) cm-3 for sample oxidation at different oxidation
temperature (373 – 973)K and from (38.2*1015 to 40*1015) cm-3 for sample oxidation at
different oxidation time (0.5 – 3.5)min. Also the porosity was (45.56%) for PS/p-Si
etching at 2min while reduce from (45% to 35.4%) with oxidation temperature, and from
(44.2% to 40.5%) with oxidation time. From photocurrent characterized, that the
photosensitivity for PS/p-Si structure is better where etching time at 2min, and its 0.2545
A/W at 370nm, and it increased after Rapid Thermal Oxidation (RTO) from (0.34 to
0.44) A/W with different oxidation temperature, and changed from (0.35 to 0.34) A/W
with different oxidation time, so that sandwich hetrojunction exhibit good efficiency
photodiode.

In this paper, the problem of designing dynamic multidrug therapies scheduling to
medicate the Human Immunodeficiency Virus (HIV) type 1 infection is described. The
control approach used for this purpose is the “State Dependent Algebraic Riccati
Equation”, (SDARE), which is one of the highly promising and rapidly emerging
methodologies for designing nonlinear feedback controllers. A nonlinear dynamical
model which consists of six states, where the interaction of the (HIV) particles with the
immune system of a human being, and the Highly Active Antiretrovirus Therapy
(HAART) as Control Inputs are described, and employed to design the dynamical
multidrug therapies.
The (SDARE) approach is applied to the (HIV) mathematical model to design a
suboptimal tracking controller to drive the states of the (HIV) model to a stationary state
in which the immune system of the (HIV) patient can be bolstered enough against the
virus in a way to lead to long-term control of the (HIV) by the immune System of (HIV)
patient by itself after discontinuation of therapy.

Quality has been emerged in the 1980s as the top strategic issue in industry.
Statistical process control (SPC) is an important element of total quality management
(TQM).Though SPC techniques were originally developed for manufacturing, they have
been successfully applied to certain administrative and service functions. The objective
of this research is to demonstrate the applicability of SPC techniques for quality control
and improvement in engineering organizations involved in construction (implementing
projects). One of the most important processes to be controlled in construction projects
(cost estimation process) has been focused on. The technique of controlling such a
process has been defined depending on reviewing the subject in the previous studies.
Adopting individual measurement charts is reached as the technique used to control this
process statistically. Practical data, represented as a list of projects implemented in 2002
by the State Company for Transportation Projects together with their estimated and
actual costs, have been obtained and considered for this purpose (through applying
individual measurement charts as a suitable technique for controlling processes
statistically) showing the applicability of SPC techniques in engineering construction
organizations which undertake projects along long period of time.

In the present work, specimens of polymeric composites were prepared from LDPE
with different wt% of TiO2 and Fe2O3 using a single screw extruder which operated at a
temperature of (150-170) Co. Results obtained reveal that after the addition of 7% of TiO2 to
LDPE, some of mechanical properties improved for example tensile strength increased from
(18.50 )MPa to (28.12) MPa tensile at break increased from (14.96) MPa to (26.02) MPa,
modulus of elasticity increased from (63) MPa to (193.98) MPa, hardness increased from
(48 ) to(75),while impact strength decreased from (0.18 ) to (0.02). After the exposure to
UV light all mechanical properties declined but pigment LDPE still has higher mechanical
properties unpigmented LDPE. Empirical equations were reached which could be used to
calculate one of the mechanical properties in terms of exposure time, weight percent of
pigment content and other mechanical properties.

In this paper, an algorithm for reconstruction of a completely lost blocks
using the discrete wavelet and multiwavelet transforms are tested under noisey
environment.
The algorithms examined in this paper do not require a DC estimation method.
While most of the previuosly reconstruction methods assume that the DC value is
available or a DC estimation is required.
The reconstruction is achieved using the Boundary Interpolation (BI) which is
based on wavelet transform. The algorithm’s performance is further improved
through the modification of the Boundary Interpolation algorithm.
Another algorithm is studied in this paper which is based on the multiwavelet
transform.
The effect of adding a Gaussian noise to the image on the performance of
reconstruction of the algorithms mentioned in this paper is studied.

The morphological properties of the freshly and oxidized porous silicon at
oxidation time (60, 90) sec were studied. A blue emission from PSi can be seen with
eyes after thermal oxidation because the increasing of energy gab due to decreased
silicon column (nano particles).Pore size and shape of n-type wafers are estimate and
correlated with optical properties before and after rapid thermal oxidation (RTO).

The flow field between two blades was analyzed numerically by solving the
steady, two dimensional and incompressible (time-mass averaged Navier- Stokes
equations). The (κ-ε) turbulent model was used to simulate the condition of the
momentum equation and to obtain the eddy viscosity. The SIMPLE algorithm is
used to satisfy velocity-pressure coupling method and to satisfy the conservation
of mass. A computer code was constructed in this work using FORTRAN 90
language to simulate the flow. The numerical results were compared with
experimental results of other researcher for flow through the cascade of axial
compressor, and were found to be in a good agreement. Three different airfoils
common, used for axial flow compressors blades, were investigated in the present
study. The study shows that stall happens. At incidence angles (-80 to 70) for
NACA 65(12)10 and (-90 to 30) for NACA 65(18)10 and (-70 to 90) for NACA
65(8)10. The result also show that stall happens when the total pressure loss is
greater than 0.06 for NACA 65(8)10 when stagger angle is greater than 450 stall
happens for total pressure loss less 0.06 as the outlet flow angle decreases.
However, the quasi-three dimensional, steady, incompressible, turbulent, adiabatic
and single-phase fluid flow inside the blade-to-blade passage of an axial flow
compressor stator was also studied and the study shows that Stall was seen to take
place at blade tips during starting.

The objective of this study was to determine the catalase activity (CAT),
ceruloplasmin activity (CP), glutathione level (GSH) in the plasma of (44) normal
donars (22 male, 22 female,) and (66) patients with bladder cancer (22 smoker male, 22
non smoker male, 22 female). Data analysis showed a significant decrease in the mean
values of CAT (89.577 ± 17.140 of a smoker male, 92.102 ± 18.898 of non-smoker
male, 90.225± 12.997 of a female) as compared to normal individuals (155.541 U/mg
Hb of a male, 150.797 U/mg Hb of a female) respectively, and GSH (0.109 ± 0.056 of a
smoker male, 0.110 ± 0.051 of non-smoker male, 0.084 ± 0.028 of a female) as
compared to normal individuals (0.838 μmol/L of a male, 0.809 μmol/L of a female)
respectively. A significant increase in the mean value of CP in plasma of patients with
bladder cancer (56.477 ± 2.671 of a smoker male,55.602 ± 3.042 of non-smoker, 52.101
± 3.212 of a female) was recorded as compared to normal individuals (43.908 IU of a
male, 41.110 IU of a female) respectively, There is also a negative relationship between
CAT & Cp and GSH & Cp levels (r = - 0.089, and r = - 0.104) respectively, while there
is a positive relationship between CAT and GSH (r = 0.081) in-patients with bladder
cancer.

In order to initiate a database on materials properties of typical lamination
used in above knee prosthetic limb socket fourteen group of different lamination
materials layers are manufactured using perlon and fiber glass and acrylic resin
.The effect of increasing and decreasing of perlon and fiber glass layers on
mechanical and physical properties are examined subjected the eighty two
manufacturing sample of the different fourteen group of lamination to tensile and
flexural test .
Results show that the lamination which was layup from three layers of perlon plus
two layers of fiber glass plus three layers of perlon gives the optimum mechanical
properties . Comparing this lamination with the standard lamination used in
Baghdad center of five layers of perlon plus two layers of fiber glass plus five
layers of perlon it can be seen that ,in spite of the big reduction in perlon layers
form ten to six layers the yield stress increased with 14.75% while ultimate
strength remains at the same value and bending stress decreased with 1.3% only . It
is recommend to use this type of lamination for the layup the above knee socket
because it meets the requirement of good socket design for acceptable mechanical
properties and its minimizing the cost of socket lamination to suitable cost value.
Also it was found that increasing the fiber glass layers from zero to two layers
with fixing perlon layers leaded to increased in( E y ult s ,s , , flex flex s ,E ) with
(40%,30.4%,110.5% 36.4%and 20.4%) respectively. At the same time the results
show that the lamination group of sandwich lay up during which the layers of
perlon distributed equally (homogeneously) on each side of the central fiber glass
layers improved the mechanical properties set ( E y ult s ,s , , flex flex s ,E ) with ((21-
59)%,(12.4-66.4)%,(46.6-150)%,(5.2-60.2)%,(27.5-44.8)%) respectively compared
with the others group of unequally distributed lamination .

This work presents the study of ozone mass transfer in water in bubble column with
0.5cm inside diameter and 2 m height. The volumetric mass transfer, rate constant of
ozone decomposition and mass transfer efficiency were studied with different gas flow
rates (50,100, 150, 200, 250) L/min.
The volumetric mass transfer as well as rate of decomposition of ozone was found to
increase with increasing gas flow rate. They were ranged between 0.21-0.41min-1 and
0.018-0.036min-1 respectively.
Mass transfer efficiency was increased from 77 to 98% with increasing gas flow rate.
A mathematical model was numerically solved to describe the liquid ozone
concentration with time. The model and experimental results agreed well.

In this work, the effect of electric field at low pressure (10-2m bar) on laser drilling
process has been studied for Stainless-Steel type (304) and brasses.
Nd: YAG pulsed laser (1.06μm) of (300μs) pulse duration at various energy ranges
between 0.5and 3J was used. The results indicated that the obtained maximum aspect
ratio for St. St. equals to (49%) at maximum used Energy. However the obtained
maximum aspect ratio for brass is (36.6%).

The Biometrics recognition systems act as an efficient method with broad
applications in the area of: security access control, personal identification to humancomputer
communication. From other hand, some biometrics have only little variation
over the population, have large intra-variability over time, or/and are not present in all
the population. To fill these gaps, a use of multimodal biometrics is a first choice
solution [1].
This paper describes a multibiometrics method for human recognition based on
new teacher vector identified as spectrum eigenface, and spectrum eigenpalm. The
proposed combination scheme exploits parallel mode capabilities of the fusion feature
vectors in matching level and invokes certain normalization techniques that increase its
robustness to variations in geometry and illumination for face and palmprint. The
correlation distance is used as a similarity measure. A threshold value is used to
prevent the imposter for being recognized. Experimental results demonstrate the
effectiveness of the new method compared to the unimodal biometrics for spectrum
eigenface/eigenpalm.

The present investigation is concerned to study the influence of poly vinyl
acetate (PVAc.) on flow behavior of bentonite dispersions in water, poly vinyl acetate
was added to the bentonite dispersion in different concentration (5, 7.5, 10, 12.5, 15, 17.5
and 20) gm/l. after that, the flow properties of these samples was measured and that
included (viscosity, shear stress, shear rate and Bingham yield value), The results show
thixotropy flow by a hysteresis loop of the flow curves for bentonite dispersion with and
without poly vinyl acetate, but with (PVAc.) give higher fluidity flow.
Also the morphology of bentonite dispersions was analyzed before and after adding
poly vinyl acetate by scanning electron micrograph (SEM), it is show that a weak
association between (PVAc.) and bentonite dispersions.

Eight design charts are presented for reinforced concrete short C-columns subjected to
axial compressive load plus uniaxial bending. For design these charts can be used for
determining the required column dimensions and amount of steel, while for analysis
these charts can be used for estimating the loaded column capacity.
Four examples are given to explain the use of design charts for both design and
analysis, two of which are design examples while the other two are analysis. It has been
shown by these examples that the new proposed charts are very simple to use in
structural applications.

Products made of polyethylene used out doors are subjected to UV-degradation. In
fact, many polymers show changes in physical properties during service lifetime, when
they are exposed to sun light and particularity to UV-light. In the present work, the
physical properties and the morphology of blends of high – density polyethylene
(HDPE)/linear-low-density polyethylene (LLDPE) studied before and after exposure to
UV –light.
HDPE was mixed with different weight percent (0, 15, 30, and 45%) of LLDPE using
the two roll mills; the mixing machine is operated at a temperature of 135 oC.
Weathering test was carried out to find the effect of the environment condition on the
physical properties of the polymeric materials by increasing the exposure times to
(100,200,300) hr. The physical properties and the morphology were specified by
measuring the (absorption properties, and densities), for the former, and
photomicrograph for the latter. The results obtained in this work show that the density of
pure HDPE and HDPE/LLDPE blends increased with the increasing the exposure time,
and that immersing the HDPE and HDPE/LLDPE blends in water can produce a variety
of damage and this damage increased with the increasing of the exposure times also, as
the amount of LLDPE is increased in the HDPE/LLDPE blends the amount of water
absorbed and diffusivity coefficient, increase greatly, and from the optical micrograph
results showed clearly the damage obtained due to exposure to UV light for 300 hr for
pure HDPE and HDPE/LLDPE blends.

This paper presented a numerical methods based on FEM were used to study
the effect of temperature on the dynamic characteristic of composite cylindrical
conical shell with different cone angle and wall thickness. The study taken into
account the effect of temperature on the material properties of the selected
material and the effect of pre stressing on the natural frequency of the shell. A
general conclusions could be obtained from the static analysis ,i.e. for higher
circumferential wave number, the effect of increasing the thickness is to produce
higher natural frequencies. The natural frequency of the system may drops by
about (12 %) as a result of the degeneration of the material properties due to
temperature elevation. The higher circumferential wave number, the more
pronounced is the influence of ply orientation on the resulting natural frequency
changing the ply orientation for 0/90/0 to 75/-75/75 may increase the natural
frequency by about (100 %). Finally the transient dynamic stresses may exceeds
the design stress by a bout (50 %).

An experimental and numerical investigation is carried out for the heat transfer from
a cube faces subjected to impinging jet which centrally strikes the top face of the cube. The
cube is subjected also to a comparatively low velocity cross flow through the duct occupying
the cube. Different factors affecting the cooling characteristics of the cube are studied as
orifice size, jet velocity and orifice to cube top distance. The results show that cross flow
increases heat rates from the cube for small size orifices and low impinging jet velocities.
Orifice sizes equal or bigger than cube size will isolate the cube from cross flow effect
especially at high impinging jet velocities.