Engineering and Technology Journal

Several approaches and techniques have been proposed to make
communication via the internet secure; one of these approaches is steganography.
Steganography is the art and science of hiding communication, a steganographic
system thus embeds hidden content in unremarkable cover media so as not to
arouse an eavesdropper’s suspicion. In this research the proposed method is a
public key steganography technique and it embeds a secret message in digital
image with multi level of security. The proposed method uses Discrete Cosine
Transform (DCT) to embed a secret message in Bit Mapped Image Format for
Microsoft Windows (BMP) image with high invisibility and high correlation
between cover-image and stego-image acceptable hiding data rate.

The operation of Modern Guidance System may be separated into two
cascaded functions
1. Filtering of the noisy measurements obtained from the sensors and 2. Utilization of
the estimated parameters to control the required acceleration.
Guidance system is enhanced by using 3rd order Kalman filter to estimate the
separation distance and its derivatives that needed in optimal controller. Slant range
and closing velocity is estimated using 2nd order Kalman filter and they also needed in
estimation of time to go.
The optimal guidance system is better than the proportional navigation, biased
proportional navigation, and the augmented proportional navigation system since it
required simple achieved acceleration.
Fading memory filter may be used to enhance the navigation system instead
of Kalman filter. It is simple in structure and need minimum time but less accuracy
than the Kalman filter

The trend in hydraulic power applications is to improve efficiency and
performance of hydraulic systems parts. This paper examines the performances of
direct operated proportional pressure relief valve type (DBETR-1X/25). There are
limitations to the closed loop performance of the valve when it is included in a
valve-controlled electro hydraulic system.
Proportional pressure relief valves are one of fundamental important elements
for modern hydraulic control systems, which used in protecting all circuit parts
from damage. These valves decreases costs and can be employed to obtain many
difference pressures by using only one proportional pressure relief valve, which
plays a vital role in automation process. Practical results obtained from this work
were satisfactory and acceptable. The experimental and theoretical resulls are
compared with data sheet from manufacture companies. A small dissimilarity has
been found, but it can not be negligible. The results are very important to the
designers and engineers, who are working in hydraulic proportional systems field,
in helping them to calculate losses accuracy and design applicable circuits to arrive
actual ideal performance for hydraulic proportional systems and not to absolutely
rely on the company ideal results.
The model is simulated using MATLAB\ SIMULINK model (R2008a) and
the theoretical results are compared to those obtained practically

The main goal of this paper lies briefly in submitting and modifying some
numerical methods for solving system of linear Fractional order Integro- Differential
Equations of Fredholm type (L.FFIDE's). in this method four kinds of shifted
Chybeshev polynomials (T*,U*,V*and W*) are used as a bases of independed
polynomials approximation fn(x) .The general fractional derivatives of these
polynomials are formulated (Da Tn* , Da U n* , Da Vn*andD aWn* ) in the
framework of the Riemann-liouville definition .Some numerical examples are
solving to show that the different between these polynomials , furthermore
Algorithms and programs by using MATLAB program are given

The aim of this paper is to present a new framework for studying capacities and
twofold integral from a point of view of two-valued logic. In this framework, we
propose equivalent definitions of capacities and twofold integral that may be more
easily interpretable. First, we define a logical capacity, then, we propose definition of
logical twofold integral with respect to logical capacities based on the two-valued
logic.

The effect of process variables on the recovery of hardness from water by
acation exchanger was studied. At steady state the process could be represented by
second order nonlinear emperical model. Although this model was less accurate than
the dynamic model,the results show agreement when compared with the experimental
data. The steady state optimization model was used to limit the operating conditions of
the system. The static feed forward control could be used with the aid of on – line
digital computer.

The basic motivation of this paper is to apply the Horner‘s method to perform
the steps in Newton and improved Newton methods for approximating the Solution
of Barker‘s equation in parabolic motion.
A simple starting value for the iterative solutions is suggested. Some Numerical
applications are presented and show that only little iteration is required to obtain
approximate solutions which are found to be accurate and efficient.

There are several heuristic search techniques, Tabu Search (TS) is one of them.
TS based on generating the neighbor states but it has several problems in its work.
This paper presents a new version of TS based on backtracking techniques (called
BTS) to reduce the effect of these problems. Two case studies have been solved using
BTS, 4-Color Map and Traveling Salesman Problem. The proposed algorithm gives
good results compare with the original, the iteration numbers are less and the local
minimum or non-optimal solutions are less

This study is concerned with the effect of heat treatment (precipitation
hardening) on notch sensitivity factor for aluminum alloy (7075). Tests were
conducted on four configurations of specimens, three of them which had external
circumferential notches with notch radii of 0.5 mm, 0.7 mm, and 1 mm. The
fourth configuration is un-notched specimens. The alloy samples which were used
in fatigue test were subjected to cold working before heat treatment. Dimensions
and roughness of the specimens were measured. The fatigue tests were performed
for different types of specimens. The (S-N) equation was derived for each group to
estimate the fatigue life under any applied stress amplitude. In addition, the
strength reduction factor (kf )and notch sensitivity factor (q) were calculated.
The results showed that the fatigue strength reduction factor were
increased after heat treatment and with decreasing notch radius. Also the notch
sensitivity factor increased with increasing notch radius and after heat treatment.
The enhancement percentage in notch sensitivity factor after the heat treatment for
1 mm radius notch was (22.616%).

Local and Global uniqueness theorem of solutions of the differential equation
have been obtained, which are applications of Bihari's and Gronwall's inequalities

This work investigates the effect of different media (0.1N of NaOH, H2SO4
and NaCl solution) on the polarization behavior of Al-Zn-Mg alloy and calculates
some of the corrosion parameters such as corrosion potential (Ecorr) and current
density (icorr), cathodic and anodic Tafel slopes (bc & ba), and the polarization
resistance (Rp) .
The results of the polarization resistance indicates that Al-Zn-Mg alloy have
resistance in slat solution higher than that observed in acidic and basic solution
respectively .
Also some of the mechanical properties like the hardness and wear were
measured. The results for hardness showed that the untreated alloy in the
experimental solutions had higher hardness than those which are treated in salt,
acidic , and basic solutions respectively .
While the results for the rate of wear at different sliding speeds showed that the
rate of wear for the samples that treated in basic solution higher than those for
samples which are treated in the acidic and salt solutions . Also the same results
were get when measure the rate of wear with different applying loads.

Stream cipher designers offer new algorithms by employing the
characteristics of the basic structure to get algorithms that have advanced features
from security and speed stand point of view. Taking into consideration the benefit
from the scientific and technical development at the publish time of their
algorithms versions. This research proposes the design of a new efficient and
secure stream cipher, named (Kangaroo) which was designed to be more secure
than conventional stream cipher systems that use XOR for mixing. The proposed
algorithm encompasses two major components. The first part involves the Pseudo
Random Number Generator (PRNG) using Rabbit algorithm. And the second part
involves a nonlinear invertible round function (combiner) to perform the
encryption and decryption processes. This will lead to strengthen the weak XOR
combiner. The proposed cipher is not a random number generator alone. Instead it
is self-synchronizing stream cipher such that - the cipher text influences its internal
functioning. The proposed algorithm uses 16-bytes secret key to encrypt the
plaintext which is multiple of 16-bytes up to (264 bytes) length. Also the
performance and memory requirements of the proposed system are evaluated. Such
that the setup stage requires 1987 operations and the encryption/decryption
processes require 4 operations per byte. And the memory requirement is 344 bytes.
The implementation was done on a (Pentium IV, 1.79 GHz, 224 MB of RAM) PC,
Windows XP, using (Java Builder 7).

In this paper, the theoretical 8-channel Dense Wave Division Multiplexing
(DWDM) telecommunication system is demonstrated. Laser Diode (LD) source
was used for each channel, with external modulator, therefore making the system
work at high bit rate. The analytical part was done using a software simulator. All
the proposed system components were simulated using Optisystem software offered
by Optiwave for testing a DWDM communication system. The 8-channel DWDM
spectrum, attenuation, dispersion, and receiver performance was determined.

Time-averaged local heat transfer coefficient profiles were studied in a 0.45
m bubble column using air-water system. The effect of the superficial gas velocity and
axial locations (Z/D) on the heat transfer coefficient and its radial (r/R) profiles were
investigated in bubble column. Significant differences were observed between heat
transfer coefficients in the axial directions viz. in the bulk flow region (Z/D=4.8)
higher than in the distributor region (Z/D=0.28) by 14% -22% for increasing the
superficial gas velocity from 0.05-0.45 m/s. The heat transfer coefficients increase
with superficial gas velocities and the values in the center of the column were 9–13%
greater than those near the wall region .The characteristics of bulk flow region are
large variation in radial direction and little in axial direction for the values of heat
transfer coefficients.

The implementation of monitoring, controlling, and archiving system with
data communication based on Bluetooth technology is described. Design and
implementation of a temperature sensing and power line frequency measurement
system is presented. The application has been accomplished using Bluetooth USB
dongle. One of the Bluetooth enabled PC acts as a server. The implementation
process consisting of application architecture design, system requirement,
software design, hardware design, establish Bluetooth connection, and
visualization of measurement data is described in detail. Experimental results
show that the designed system is more reliable and easy to use.

Many applications with real-time demands are composed of mixed sets of
tasks with a variety of requirements. These can be used in the form of standard
timing constraints or flow of data. Therefore you need real time multitasking
operating system to guarantee within a fixed amount of time. Scheduling
Algorithm for real-time multitask operating system is implemented according to
the priority of tasks depending on nature of their jobs and need to resource or time.
The Scheduling algorithm which used here is event driven, not clock driven.
It is necessary in data communication system which is an example of real
time system to record the received messages for documentation and for further use
like for simulation or computation or reply them. The time which saved with each
message is important to be close to the real situation. The system is written in C++
programming language under DOS environment

M.S.Abbas [1] introduced and studied the concept of fully stable Rmodules
and called a ring R is fully stable ( pseudo - stable ) if it is fully
stable ( pseudo - stable ) R-module . And A.M.Abdul-Daim [2] introduced and
studied the concept of fully – stable rings as a generalization of fully stable
rings .
The purpose of this paper is to generalize the concept of fully
pseudo – stable rings to fully – pseudo - stable rings . Some properties and
characterizations of fully – pseudo – stable rings are obtained . A condition is
given such that a fully – pseudo – stable ring is fully – stable

In as much as employ activity of the laser in industrial applications specially in
the drilling & cutting works, it is important to study all variables & factors that affect
efficiency & speed of performance such as that processes. In this paper, the study of
the focusing effect of laser beam on the penetrating & cutting speed was done, through
deriving the mathematical equations, and re-wording it to demonstrating clearly the
role of the focusing system on application speed, and calculate the variations of the
efficiency of these processes.
The results demonstrated that the application speed (penetration, cutting)
affected by the changing in the radius of laser beam, these variables were studied from
one hand by comparing the cutting speed with and without the beam expander, where
in CO2 laser case it raised from (1.56 mm/sec) to (7.78 mm/sec) and from the other
hand by using a number of concentrating lenses in the focusing system to show its
effects on the application speed. Where the focal length of this lenses has a negative
effect on the degradation of the cutting speed while, it has a double negative effect on
the degradation of the penetration speed, where the degradation in penetration and
cutting speed (0.574) and (0.384) respectively with change in collimated lens focal
length about (100 - 200 mm).

Integral equation of the second kind which has, extensively, been solved by
different ways, but not this one that deals with the collocation method using Bernstein
polynomials together with some useful examples to declare the method.

A number of criteria have been considered during this study. These criteria
include preparation and fractionation of brucellins using chromatography. Several
peaks were obtained in each brucellin fractionation.
The third criteria was immunization of 5 groups of guinea pigs .The fourth
criteria was the using of serum of immunized animals in ELISA test against
peaks resulted from fractionation . Peak 1 of Rev1 brucellins show the highest
positive results and considered as the responsible part of immunization against
brucellosis .