Print ISSN: 1681-6900

Online ISSN: 2412-0758

Volume 30, Issue 5

Volume 30, Issue 5, March 2012, Page 697-919


Reliance on Ground Coordinate Measurements Produced by DGPS Post-Processing

Abdul Razzak.T.Ziboon; Lubna.AL-Shammari

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 697-709

Some users of the GPS take the coordinates and the distances between points as they are in the field and try to joint work with the total station, but they found a difference between the coordinates and the distances. The reason is that these measurements are three-dimensional Coordinates: where they are represented on the model of the Earth,
while the total station based on the theory of plan survey are two-dimensional coordinates. And other causes the distortion resulting from the projection itself. From the scientific point of view, all the solutions applied for this problem are not accurately enough, but serve their purpose. Where as in this research we are trying to cancel the differences in the coordinates and the distances between the GPS and the total station measurements. Where work on a project using both techniques (GPS, and Total station) .The coordinates of the project are measured on the site by considering the total length of the project (35km) and ten control points as base line points had been distributed along the route including the X and Y coordinates corresponding to the zone 38N. It was found that the DGPS Software (Topcon Tools v7) or other data collection software can be used to convert the coordinates from grid coordinates to ground coordinates and then these coordinates can be used with the total station in the field for small distances. But for large distances the ground coordinates that obtained from Total station instrument must be used to avoid accumulative error. And must also take into account when choosing sites of the control network in the field where it should be direct view between the control network points to get rid of random errors resulting from the use total station
this in turn leads to obtain high accuracy results for the ground coordinates.

Real-time Partial Encryption of Oigital Video using Symmetric Dynamic Dual Keys Algorithm (SDD)

Basima Z.Yaco; AbdulMonem S. Rahma

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 710-728

In recent years, as digital video technologies have been broadly used in TV,communication and multimedia. Security and privacy issues of the transmitted data have become an important concern in multimedia technology. Digital video stream is quite different from traditional textual data because interframe dependencies exist in digital video. Special digital video encryption algorithms are required because of their special characteristics, such as coding structure, large
amount of data and real-time constraints. This paper presents a real-time partial encryption to digital video technique based on
Symmetric Dynamic Dual (SDD) keys algorithm which is fast enough to meet the realtime requirements with high level of security.
This approach uses dual key for encryption with variable (dynamic) block bits size,each block bits size (3 or 4 bits ) are interpreted as an element of a finite field.. The first key is called control key determines the length of bits block (3 or 4 bits block) size to
encrypt, and the second key is used for encryption by using a equation:
Y = X. A+ BWhereX is bits block, AandB are the encryption keys.
The mathematical operations addition and multiplication in this equation are based on
mathematical theory of Galois field GF(2 ).
In this technique the I-frame (Intra-frame ) of the digital video scene is extracted
and decomposed the color picture into its three color channels:luma channel (Y) and
two chrominance channels Cb and Cr,with note that the frames of digital video is in
YCbCr color system, the SDD algorithm is applied to the Y channel.
The encryption algorithm achieves best timing results, and it provides high level of
security by its great resistant against brute force attacks, because it uses dual key and
dynamic block cipher, hence it will be very difficult to guess the key. To decrypt the
ciphertext with 128 bits, the attacker needs 8.86569157e+188 of possibilities of keys as
minimum and 7.91569097e+253 as maximum.

Linear Damage Rule Life Prediction for Stress Controlled Fatigue-Creep Interaction of Aluminum Alloys

Salah F. Abd-El-Jabbar; Shakir Sakran Hassan; Hussain J. Al-Alkawi

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 729-743

The fatigue-creep interaction performance of 5086 and 6061-T651 aluminum
alloys were investigated for specimens tested under control stress rotating bending at a stress ratio R=-1 and 250°C temperature. The fatigue endurance limit for both alloys reduced at 250°C.
The fatigue and creep damage was evaluated based on the linear damage rule, where the fatigue damage was determined as the number of cycles to failure and the creep damage was evaluated based on the time applied experimentally for low to high and high to low amplitude stress. The cumulative fatigue-creep interaction damage was found to around 0.5 i.e DF +Dc =0.5 Fatigue – creep interaction lives predicted by the linear damage rule were compared to the actual lives. The results show that the linear damage rule gave an overestimated predictions.

Performance Evaluation of Spatial Multiplexing MIMO Systems with Various Detection Schemes

Mahmood. Farhan Mosleh

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 744-754

Spatial Multiplexing (SM) over multiple-input multiple output (MIMO) channels significantly improves the data rates over wireless channels. The challenge is to design low complexity and high performance algorithms that capable of accurately detecting the transmitted signals. In this paper, the general model of MIMO communication
system was introduced in addition to several MIMO Spatial Multiplexing (SM) detection techniques. The Bit Error Rate (BER) performance and computational complexity of Minimum Mean Square Error (MMSE), Zero Forcing (ZF), and Maximum Likelihood (ML) detection schemes have been analyzed and compared to each other using Matlab R2009b. Results of simulation illustrates that their performances of MMSE and ZF detectors are close together and need more than 14 dB of Signal to Noise Ratio (SNR) to achieve 10-4 BER. On the other hand ML detector shows better results than MMSE and ZF detectors but the complexity and the delay are
large. Been proposed to install the number of transmitter antennas fixed on 2 and change receiving antennas 2, 3, and 4. Results showed that the present proposal came close to the results of the previous model, but less complexity

Biomechanical Analysis of Human Stair Climbing (Ascending and Descending)

Sadiq Jafer Abbass

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 755-774

Because stair climbing is a common activity of daily living, the ability to do it efficiently is important to an individual's quality of life. More demanding than level walking, stair ambulation is performed with ease by healthy individuals; however, it is more difficult to perform for those with decrements in motor function, balance
problems, or reduced lower-limb function. The difficulty with stair climbing is attributable to increased muscular demands, which are reflected in larger forces, angles, powers, moments, and ranges of motion, and these increased demands occur consistently at the knee joint. Kinematic system is used in stair climbing to record the position and orientation of the body segments, the angles of the joints and the corresponding linear and angular velocities and acceleration. The purpose of the study is to show an ideal kinematics appearance of human gait cycle for stair climbing in order to get measurement values
that can be depended on in the hospitals of rehabilitation, the centers of physical therapy and the clinical of medical sports as a reference data for kinematic joint parameter. In this study, 5 subjects were selected from the society, then a video recording was made for them by using a single digital video camera recorder fitted on a stand of three legs in a sagittal plane while subjects climbing a stair one by one for
different stair heights. Motion analysis was used to study the knee and hip joint kinematics. As a result, it was observed that the range of motion at the hip joint is between (10°-70°) at ascending and the range is between (20°-50°) at descending. The range of motion at the knee joint is between (20°-90°) at ascending and the range is
between (10°-100°) at descending. The range of motion at the ankle joint is between (-25°-20°) at ascending and the range is between (-25°-15°) at descending. Also it was found that the angular velocity at the hip joint is between (-10-10) deg/s for ascending and (-15-25) deg/s for descending. The angular velocity at the knee joint is
between (-40-30) deg/s for ascending and (-30-50) deg/s for descending. The angular velocity at the ankle joint is between (-30-20) deg/s for ascending and (-15-15) deg/s for descending. In this study, biomechanical characteristics of lower limb joint upon
various stair height were presented and these data can be applied to biomedical research field that include wearable walking assistant robot.

Study the Effect of Anisotropy on the Magnitude of Fracture Zone of Sheared Edge from the Sheet Metal

Abdullah H. Singal

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 775-784

The quality of product is related to the shape of blanked edge. The blanking process is referring to a shearing or punching process. In this work an experimental investigation to the blanking process was carried out using cutting die with three groups of specimens at different direction (0¢ª, 45¢ª, 90¢ª) with respect to the sheet
rolling direction. The aim of this work is to study the effect of anisotropy on the characteristic features of sheared edge of aluminum sheet (Al-1100) with (2mm) thickness. The results of the experimental investigation show the effect of anisotropy on the magnitude of fracture zone for the sheared edges and on the shearing forcepunch
displacements curves. The rolling direction at 0¢ª is the best shape which it has the less fracture zone (50%) and the less shearing force and that led to better dimensions with respect to other directions at 90¢ª and at 45¢ª.

Personal Text Summarization in Mobile Device

Alaa Kadhim

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 785-794

This paper presents a hybrid text summarization for mobile device to summarize a selected text. The system can be proceeds by statistic or heuristic methods. With the statistic and heuristic the summary is found based on combined statistic features and heuristic features like word frequency, position, length of sentences, and similarity
with the document title. The results shows that the time with proposed system is less than without it during the retrieving the text with selected keywords.

Performance Analysis of Framelet Based OFDM System Under Different Channel Conditions

Atheer A. Sabri; Ziad Q. Abdulkareem

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 795-810

In this paper, the Framelet Transform (FT) is proposed as a new modulation technique in the realization of Orthogonal Frequency Division Multiplexing (OFDM). Framelet Transform (FT) is used in the OFDM structure to serve as a modulator instead of conventional Fast Fourier techniques. As a result, the proposed FT-OFDM system improves Bit Error Rate (BER) performance, and keeps bandwidth efficiency and spectrum shape as good as conventional Fast Fourier transform (FFT)-based OFDM. The new structure was tested and compared with conventional FFT- OFDM, Wavelet based OFDM system (DWTOFDM), Multi-Wavelet based OFDM system (DMWT-OFDM), Packet-Wavelet based OFDM system (PWT-OFDM) and the proposed Framelet based OFDM system (FT-OFDM), for Additive White Gaussian Noise (AWGN), flat, and multi-path selective fading channels.

The Performance Enhancement Study of FIR Filters Based on Adjustable Window Function

Najat Sh.Jasim Mohammed

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 811-831

The aims of this study are enhancement the performance of low pass FIR
(Finite Impulse Response) Filters by using adjustable window design method, and reduce the amplitude of side lobes and Gibbs phenomenon problems in these filters,also study the effect of different orders of low pass FIR filters (20th ,70th, 200th ) on its performance when the parameter β in fixed value in the time domain and frequency domain, and investigate the effect of different values of parameter β=0.5,3,6,9 on its performance when the filter order in fixed value in the time
domain and frequency domain.These filters are used in the ECG signal applications to remove high frequency noise. The simulation of design these filters is implementing by using FDA tool (filter design and analysis tool) and wintool (window tool) from matlab (R2010a)
program. The study results have been obtained the lowest value of relative side lobe attenuation= -66.2dB with thin main lobe width = 0.016602 when the filter order and the parameter β are equal to 200th, 9 respectively, we find that Kaiser window function is the optimum window to reduce side lobe amplitude and to reduce the Gibbs phenomenon with control of the main lobe width as compared with other windows such as Hamming, Bartlett, Blackman and Rectangular, and gives much better stop band attenuation than the Parks-McClellan algorithm.

Stability and Convergence of Explicit Difference Method for Solving the 3-Dimensional Two-Sided Fractional Diffusion Equation

Iman Isho Gorial

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 832-848

In this paper, a numerical solution of the 3-dimensional two-sided fractional
diffusion equation has been presented. The algorithm for the numerical solution for
this equation is based on explicit finite difference method. The consistency, conditional
stability, and convergence of the fractional order numerical method are described.
The numerical method has been applied to solve a practical numerical example and
the results have been compared with exact solution. The results were presented in
tables using the MathCAD 12 software package when it is needed. The explicit finite
difference method appeared to be effective and reliable in solving the 3-dimensional
two-sided fractional Diffusion equation

Enhancement of Porous Silicon Formation by Using Ultrasonic Vibrations

Ali H. Al-Hamdani

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 849-854

Anodic electrochemical etching enhanced by ultrasonically is developed to fabricate luminescent porous silicon (PS) material. The samples prepared by the new etching method exhibit superior characteristics to those prepared by conventional direct current etching. By applying ultrasonically enhanced etching, PS microcavities with much higher quality factors can be fabricated. The improved quality induced by
ultrasonic etching can be ascribed to increased rates of escape of hydrogen bubbles and other etched chemical species from the porous silicon pores surface.

Structural, Chemical and Morphological of Porous Silicon Produced by Electrochemical Etching

Amna A. Salman; Fatima I. Sultan; Uday M. Nayef

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 855-867

In this paper, the nanocrystalline porous silicon (PS) films is prepared by electrochemical etching of p-type silicon wafer with different currents density (15 and 30 mA/cm2) and etching times on the formation nano-sized pore array with a dimension of around few hundreds nanometric. The films were characterized by the measurement of XRD, FTIR spectroscopy and atomic force microscopy properties.
We have estimated crystallites size from X-Ray diffraction about nanoscale for porous silicon and Atomic Force microscopy confirms the nanometric size Chemical fictionalization during the electrochemical etching show on surface chemical composition of PS. The etching possesses inhomogeneous microstructures that contain a-Si clusters (Si3–Si–H) dispersed in amorphous silica matrix and (O-SiO,
C-SiO). From the FTIR analyses showed that the Si dangling bonds of the as-prepared PS layer have large amount of Hydrogen to form weak Si–H bonds. The atomic force microscopy investigation shows the rough silicon surface, with increasing etching process (current density and etching time) porous structure nucleates which leads to an increase in the depth and width (diameter) of surface pits. Consequently, the surface roughness also increases.

A Model for The Prediction of Fracture Toughness Using Neural Network

Aseel abdulbaky; Dhafer Al-Fattal; Harry Bhadeshia; Talal Abdul Jabbar

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 868-885

The purpose of this research programme is to develop quantitative models for the prediction of mechanical properties (fracture toughness) using experimental data collected from the literature, together with a powerful computational technique known as neural network. Creating a truly general model requires a combination of available data and metallurgical knowledge. This model is proposed for martensitic and ordinary bainitic steels in addition to the more recent class of non-structural super-bainitic steels. Super-bainitic steels are
attractive for many applications such as armour. The model of fracture toughness, based on chemical composition, heat treatment an
d mechanical properties is proposed. The predictions of fracture toughness are generally acceptable but the uncertainties
are high and more input data need to be collected for super-bainitic steels when available in the future to improve the predictions of this model.

The Effect of Annealing on the Physical Properties of Thermally Evaporated Cadmium Sulphide Thin Films

Shatha Shammon Batros

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 886-896

Pure CdS thin films with different condition have been successfully deposited by thermal evaporation in vacuum on glass slide substrates. The substrates temperature of about 100oC and the vacuum of about 10-6 torr. The film was annealing with different temperature (300 to 500oC) and different time of annealing (10 to 85min). The film structure properties were characterized by x-ray diffraction (XRD). XRD
patterns indicated the presence of single –phase hexagonal CdS with good crystalline, some of the structural characterization such as lattice constant, average grain size and micro strain are calculated from the X-rays pattern. The average roughness was obtained by using AFM scanning microscope, which shows that the average roughness decreased with increase the annealing temperature. Direct band gap
values of (2.35 to 2.15eV) for different annealing temperature (300-500oC) and (2.34 to 2.33eV) for (10min to 85min) annealing time at 200oC annealing temperature respectively, the transmission value of prepared samples are between (50-80%).

Reduction Reactive Power and Collapse Voltage Using Series Capacitors Compensation in Sudden Change Loads of Transmission Lines

Hussein Thani Rishag

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 897-919

The continuous increase of disturbances on the interconnected electric power system resulting in its inability to reliably meet demands. This paper presents an application of a series capacitor compensation in transmission line and shunt reactors. Wherever all inductive loads required two kinds of power to operate with active power (P) and reactive power (Q) in design and operation of alternating current electric power systems. There is an important interrelation between reactive power and voltage of electrical power system
which depends on losses compensation using series capacitors compensation. The reactive power losses in power system distribution can be reduced by connect series capacitors and shunt reactors with transmission lines. From noticing the location of reactive power control in distribution substation we can see the reactive power, series
capacitors and shunt reactors, economical considerations which are effected on selection of using apparatus and equipments in power stations. Certain switching conditions of circuit breakers of electric power systems can result very high transient recovery voltages
comparing with its normal conditions of working. Using Metal-oxide varistor (MOV) and shunt reactors helping on damping high voltages and return systems to its normal state. The paper describes how can we design and implement series capacitors compensation to solve problem working of reactive power and collapse voltage in transmission lines using simulation methods.