Engineering and Technology Journal

This paper attempts to develop a simple, stronger and safer cryptographic algorithm which would not only be a secure one, but also reduces total time taken for encryption and decryption. The modified algorithm MTEA is a new secret-key block cipher of 64 bit that uses good features of Tiny Encryption Algorithm (TEA) and RC6 algorithms. The proposal algorithm uses the RC6 encryption algorithm as key scheduling to generate subkey. These generated key will be used in META algorithm's round. An effort is made to enhance performance of the resulting algorithm. Proposed MTEA algorithm improved TEA algorithm which is a simple classical Feistel network with 64 rounds and operating on 64 bit blocks of plaintext to produce 64 bit blocks of ciphertext with 128 bit key.

Dual tree complex discrete wavelet transform is implemented for denoising as
an important image processing application. Two wavelet trees are used, one
generating the real part of the wavelet coefficients tree and the other generating the
imaginary part tree.
A general computer program computing two dimensional dual tree complex
wavelet transform is written using MatLab V.7.0. for a general (NxN) two
dimensional signal.
This paper introduces firstly a proposed method of computing one and twodimensional
dual tree complex wavelet transform .The proposed method reduces
heavily processing time for decomposition of image keeping or overcoming the
quality of reconstructed images. Also, the inverse procedures of all the above
transform for multi- dimensional cases verified.
Secondly, many techniques are implemented for denoising of gray scale image.
A new threshold method is proposed and compared with the other thresholding
methods. For hard thresholding, PSNR gives (13.548) value while the PSNR was
increased in the proposed soft thresholding, it gives (14.1734) PSNR value when
the noise variance is (20).
Denoising schemes are tested on Peppers noise image to find its effect on
denoising application. The noisy version has SNR equals to (11.9373 dB), the
denoising image using WT has SNR equals to (17.4661 dB), the denoising image
using SWT has SNR equals to (18.1459 dB), the denoising image using WPT has
SNR equals to (19.3640 dB), the denoising image using Complex Discrete
Wavelet Transform has SNR equals to (21.9138 dB) using hard threshold and has
SNR equals to (22.1393 dB) using soft threshold. Matlab V.7.0 is used for
simulation

A derivation of an analytical expression for the mode-coherence coefficients
of uniform-distributed wave propagating within different homogeneous media – as
in case of hyperbolic Gaussian beams – was presented and a simple method of
superposition of two such beams was proposed. The results obtained from this
work are highly-qualitative applicable in study and analysis of the propagation of
Hermite-Gaussian beams especially in the problems of radiation-matter interaction
and propagation of laser beam employed in modern free-space and fiber optical
communications

The use of polymer blends is an effective method for altering the performance of
polymer materials and is widely employed in engineering plastics, rubber, and fiber
materials. Elastomeric blends are used for many reasons such as lowering the
compound cost, for ease of fabrication and to improve the performance of the
industrial rubber. In this study, 20 different rubber compounds were prepared by using
SMR-20 type of natural rubber and SBR-1502 type of styrene–butadiene rubber in
different levels (0, 25, 50, 75 and 100 pphr) and each recipe reinforced with carbon
black at different ratio (20, 40, 60 and 80) pphr (part per hundred). The physical
properties – such as thermal conductivity, thermal diffusivity, swelling and specific
gravity were studied. The results show that the thermal conductivity and thermal
diffusivity increased with increase of loading level of carbon black and these
properties decreased with the increase of NR to SBR. The swelling property in this
work measured by change in mass method by immersed the samples in oil and water.
The swelling in water more than in oil, change in mass of the NR/SBR blends
increased with immersing time increase and decreased with carbon black increment,
and with the increment of NR percentages to SBR. The specific gravity increased with
increase of carbon black loading for all recipes

The optical design of miniaturized high resolution micro lens arrays systems
MLAs, for scanning and image formation, is achieved. The types of scanner systems
that have been handled are microlens array MLA scanner system with f-number F#
2.54, for two scanning angles. The one with higher scanning angle predicts the
influence of increasing aberrations on the output. The imaging capabilities of single
and multiple array systems are presented. Their performance characteristics are
studied and analyzed to fit medical applications, the most important are compactness
and resolution. The overall size of the designed systems is a fraction of a centimeter
and the resolution is in a few micrometers regime. However, it is found that
optimizations are needed to enhance the quality of images, specifically for larger
scanning angles

Recently, many attempts were made to use metal fiber reinforcements to
improve some soil properties. In this research, the effects of fibers on the
compaction and mechanical properties of cement and lime stabilized soils (silty
and clayey soils respectively) were studied. Variables such as stabilizer (cement
and lime) content, amount and type of metal fibers were studied. Results indicated
that the addition of fibers lead to increase in the maximum dry unit weight. On the
other hand, a maximum values of unconfined and tensile strength were obtained
with the addition of 0.5 % short fiber (FS) and 1.5 % long fiber (FL) respectively.
During the flexural test a brittle manner failure was observed for the unreinforced
samples and samples prepared with little amount of fibers 0.5%. Finally, the
addition of fibers increases the fracture energy of cement stabilized silty soil and
lime stabilized clayey soil

In this research mechanical properties of high performance carbon fiber concrete
are studied. The experimental work includes, producing high performance concrete
using superplasticizer and condensed silica fume reinforced with different volume
fractions (0%, 0.2%, 0.3%, 0.4% and 0.5%) of carbon fibers. The effect of chopped
carbon fibers on the mechanical properties (compressive strength, splitting tensile and
flexural strengths, and modulus of elasticity) of high performance concrete was also
studied. Generally, the results show that the addition of carbon fibers improves the
mechanical properties of high performance concrete. Also the results show that Using
condensed silica fume as addition by weight of cement increases the compressive
strength more than that as replacement by weight of cement. The percentages increase
in compressive strength of concrete containing 15% silica fume as replacement and as
addition by weight of cement are about 14% and 26% respectively. The addition of
carbon fibers causes a slight increase in compressive strength and modulus of
elasticity of high performance concrete when the fiber volume fraction increases,
while the splitting tensile and flexural strengths shows a significant increase relative
to the reference high performance concrete (without fiber). The percentage increase in
splitting tensile and flexural strengths for high performance concrete with fiber
volume fraction 0.5% at 28 days is about 45% and 46% respectively.

Based on compressive stress – compressive strain curves of Reactive Powder
Concrete (RPC) which have been established recently in a Ph.D thesis(1), an
equivalent bi-linear compressive stress block for RPC sections under pure
bending moment is proposed and used to derive an equation for calculating the
nominal ultimate bending moment capacity (Mn) of rectangular singly reinforced
RPC sections. The accuracy of the derived equation of Mn is examined by
comparison with the results of existing experimental tests

In this paper, a new pitch extraction method is established to be employed in
improving the performance of the eigenvoices problem. This required indexing the
pitch of the voice in a document matrix and then mapping the voice documents into
preserved semantic features. The proposed voice recognition system was built to be
operated in two phases; enrollment and recognition. Closed dataset of different
voices belong to different sexes and ages of speakers were enrolled in the first
phase. The results of the recognition phase were promising of about 81% for both
sexes. This ensures the successful recognition task and the efficiency of the
proposed system.

The transonic flow past unswept and swept wings has been studied. For this
purpose the transonic potential flow equation is solved for inviscid compressible flow.
The shock waves are replaced by discontinuities across which the entropy is
conserved. The velocity field and pressure coefficients are estimated as function of
free stream Mach number. The results show the effect of free stream Mach number on
shock waves location and the velocity field around the wing section. The Euler
solution and potential flow solutions are identical at subsonic flow; however, at
supersonic flow the potential theory can no longer predict the flow field correctly. The
results show the important effect of sweep angle on the value of the critical Mach
number for wings. By using Visual foil plus the pressure distribution and lift
coefficient and Mach contours for flow Past a NACA 0012 airfoil can be predicted

Low density parity check (LDPC) codes are one of the best error correcting
codes in today’s coding world and are known to approach the Shannon limit. As
with all other channel coding schemes, LDPC codes add redundancy to the
uncoded input data to make it more immune to channel impairments. In this paper,
the impact of low-Density Parity-Check code (LDPC) on the performance of
system under Binary Phase Shift keying (BPSK) over an Additive White Gaussian
Noise (AWGN) and other fading (Raleigh and Rician) channels is investigated.
Obtained results show that LDPC can improve transceiver system for various
channel types. At Bit Error Rate (BER) of 10-4 such code with code rate of ½
reduces the Signal to Noise Ratio (SNR) by range of 6.5 to 9 dB for fading
channels in contrast to uncoded system. By studying modern research it has been
found that turbo code can achieved same manner but LDPC decoder faster than
turbo decoder and can be implemented in parallel.

Owed to wide use of pulsed lasers in a medical field, a deep understanding of
their effects on the temperature increase in tissue and the subsequent tissue thermal
damage in a coagulation process may be a matter of importance. The influence of
laser beam profile, repetition rate and pulse width on temperature distribution and the
subsequent thermal damage in tissue are studied using finite element method, which
solves the axis-symmetry bio-heat equation in tissue subjected to far IR pulse laser
irradiation. Some conclusions are obtained: as energy/pulseP remains constant,
Gaussian laser beam profile rather than a top-hat beam will increase the in-depth
tissue thermal damage at and near the center of the spot region, increasing in
repetition rate will increase the temperature distribution and subsequent damage zone.
As pulse width decrease, high temperature may be reached leading to cause a
quantitatively and qualitatively damage which can be recognize as an increase in the
size of the damage zone and a higher value of thermal dose. An increase in pulse
width will reduce the rate at which energy deposed in the tissue which result in low
extent of temperature increase which result in reduction of the damage zone
quantitatively and qualitatively.

A virus is a self-replicating program that spreads by inserting copies of itself
into other executable code or documents. a macro virus is a virus that is written in a
macro language, a language built into a software application such as a Word
processor, and causes a sequence of actions to be performed automatically when
the application is started or something else triggers it.
The aim of this paper is to upgrade heuristic antiviruses, especially, which
dealt with macro viruses by finding new features no taken into account to detect
such viruses. This is done by building undetected computer macro virus.
This paper explains a construction of a macro virus that works under all versions of
Microsoft Word (compatible virus) and infects data Documents that belong to MSWord
(Most well known and widely-used program in the world). Also, the
proposed virus is undetected by most current commercial antivirus programs
especially which used heuristic techniques and other techniques to detect unknown
viruses. Thus, it can reveal some related antivirus vulnerabilities.

The main purpose of this work is to find the primary decomposition of factor
group K (The factor group of all z-valued class functions
module the group of Z-valued generalized characters for elementary abelian group
G),where G is a finite abelian group of type , p=3.
This work depends on finding the rational valued character matrix
from the character table of and finding the invariant factors of this matrix.
We have used the MATLAB program to calculate some results of this work

The paper is focused on the application of the response surface method (RSM)
in structural optimization. Applications of the response surface method in the
design of composite laminated plate have been discussed. The response surface
method consists of two stages. In the first stage, the random variables is selected in
order to perform a deterministic computer simulation (finite element solution) in
the sample points. In the second stage, the approximation of the function (which
represent the buckling load) is performed in order to obtain response surfaces
using PDS module included in the ANSYS Program. This response surface is
incorporated into a genetic algorithm (GAs) for optimization of random input
variables to obtain maximum buckling load for composite laminated plate
subjected to both mechanical and thermal loading. GAs are stochastic optimization
algorithms based on natural selection and genetics. In contrast to traditional
gradient-based methods, GAs work on populations of solutions which evolve
typically over hundreds of generations. Four and five different variable
formulations are examined. It was found that for SSSS boundary condition and two
layer laminate the optimum values of buckling load for all thermal loading occur at
q1=33o, q2=59o, t1=1.23 mm and t2= 1.25 mm, also it can observe that the
significant random variable are t1 and t3 (in the case of five independent variables)
since the value of buckling load effected with t1 and t3 more than for t2.

The meaning of the Particle Swarm Optimization (PSO) refers to a relatively
new family of algorithms that may be used to find optimal (or near optimal)
solutions to numerical and qualitative problems.
The genetic algorithm (GA) is an adaptive search method that has the ability for a
smart search to find the best solution and to reduce the number of trials and time
required for obtaining the optimal solution.
The aim of this paper is to use the PSO to solve some kinds of two variables function
which submits to optimize function filed. We investigate a comparison study between
PSO and GA to this kind of problems. The experimental results reported will shed
more light into which algorithm is best in solving optimization problems.
The work shows the iteration results obtained with implementation in Delphi
version 6.0 visual programming language exploiting the object oriented tools of
this language.

The aim of this paper is to study the effect of Nitro carburizing on adhesive
wear resistance of carbon steel (1020 AISI). Four groups of specimens were
manufactured (A, B, C, D) with dimensions (D20*10 mm) according to ASTM
standard . Liquid nitriding at 550 °C for one hour was applied for group B, liquid
carburizing at 950°C for one hour was applied for group C, and double process of
nitriding the carburizing in the same conditions as mentioned before was applied
for group D. The hardness test, the adhesive wear resistance at different conditions
(time, sliding velocity and load) and photo microstructure was checked by optical
microscope, then phases was examined by the X-ray diffraction technique for all
the specimens. It is found that the adhesive wear resistance was improved by all
surface heat treatment. Nitriding and carburizing but Nitro carburizing it found that
best improvement.

This research is a numerical study to determine the impact of changing the
shape of absorber plate on the temperature distribution of the solar storage
collector used to heat and store water at the same time. Absorber plate in a
parabolic shape was used with different cases and study of the shape that gives the
best distribution of temperature, by using a computer program based on (C.F.D)
(computer fluid dynamic) to study the equations governing the flow of fluid freely
within the storage collector as a result of solar irradiance falling upon. these
equations is the equation of continuity , equations momentum in tow directions and
the energy equation, solved these equations using the method (vortex - stream
function) for a full breakdown of the temperature and flow within the storage
collector . The results showed the possibility of improving thermal gradient for this
type of storage collector through the use of absorber plate Followed by a parabolic
equation and it gives maximum and minimum temperature (55 , 24 °C)
respectively, offset by (41 , 19 °C) of the flat plate storage solar collector ,it
inclined at an angle (◦ 45) on the horizon

The floor tiles (mozaek) used largely to finish floor. These are different from
kind to kind according to the size of the rock that used in the surface layer with its
dimension and external form.
The size of the rock in the surface layer affect on the cost and floor tiles
specifications; it has been noticed in the results of lab- test for the samples
according to Iraqi specification no. (1042) year (1984).The changes in the size of
the rock in floor tiles make changes in the lab- test results especially in the
modulus of rupture test which is the most important to indicator to know the floor
tiles goodness the modulus of rupture decreases with the increasing of the marble
rock size which is used in the surface layer . Absorbent and the total absorbent test
noticed the test results change according to size marble rock changes.there are
increase with the increasing of marble rock size. also the cost related to marble
rock size as the rock consider the essential material which controlling the floor tiles
cost, because there is a big contrast in marble rock price in different size.so the
increase in the cost was 35%btween smallest and largest size.

An optical window for mid infrared region (8-12)mm has been fabricated by
depositing Yttrium oxide (Y2O3) on zinc selenide (ZnSe) substrate.
The effect of accelerating voltages has been studied in order to control the
quality of the thin film.
It has been found that the best transmission of (Y2O3) thin film on ZnSe
substrate is about 98% when an accelerating voltage of 5kv has been applied, for
thin film thickness of quarter of design wavelength (10mm).