Journal of Engineering and Sustainable Development (JEASD)

The contourlet transform, one of the recent geometrical transform offers the two important features of anisotropy scaling law and directionality, but non-ideal filters are used which results in two important problems, first is the pseudo-Gibbs phenomena around singularities produced by the Laplacian pyramid stage. Sharp frequency localized contourlet transform (SFLCT) is a new construction contourlet which succeeded in solving this problem by replacing the Laplacian pyramid with a new multiscale decomposition defined in the frequency domain. But the shift variant, the second problem was not solved by this work due to the downsampling of Laplacian pyramid and DFB stages. In this work, a high-performance quincunx filter banks are used in the DFB stage of SFLCT and noble identity is employed to solve the problem introduced by the downsampler and upsampler. The simulations illustrate significant improvements under the proposed transform when compared with other transform variations.

In this paper, a face recognition system for personal identification using Discret Wavelet Transform(DWT), Principle component Analysis (PCA) and Back-propagation Neural Network is proposed. The system consists of three steps. In first step pre-processing (de-noising and face detection based on skin color in RGB color space) are applied on the input image. The DWT is used to generate the feature images from individual wavelet sub bands. Only the low frequency band constructed from Wavelet Coefficients are used as a feature vector for the further process. The Principal Component Analysis (PCA) is used to reduce the dimensionality of the feature vector. Reduced feature vector are used for further classification using neural network Classifier. The proposed approaches are tested on a number of face images. Experimental results demonstrate the higher degree performance of this algorithm.

The process of extracting interesting and unknown information from large database is called as association rule technology. The typical approach for solving association rule problem is Apriori Algorithm developed by Agrawal et al.[1993]. Most of the related existed works are improvements to this algorithm. The limitations of these algorithms are: (1) they required high storage space for saving the huge data resulting the generation of the frequent itemset, (2) they required encoding scheme where separate symbols are used for each possible value of an attribute of the itemset.In the present work, another trend of solution is proposed. First, we use Genetic Algorithm (GA) to define the maximal frequent itemset, so no huge storage requirement is needed. Also, we force the (GA) to work directly on database, so no encoding scheme is required. The calculations are based on our suggestion to use the variable length individual in the population.

This paper uses the Divide-and-Conquer DFT/IDFT computation approach instead of direct computation approach in OFDM system introducing a proposed system called Quadrature OFDM (Q-OFDM). The use of this approach introduces a multi sub-channels each have a set of subcarriers orthogonal with each other in two orthogonal coordinates. This arrangement leads to decrease the probability that all subcarriers in a sub-channel see deep fading. Furthermore, this approach reduces the computational complexity and reducing peak-to-average power ratio problem which are common problems in common OFDM systems especially when large number of carriers is used. The performance of the Q-OFDM system has been tested and compared with conventional OFDM system in AWGN, flat fading and selective fading channels. The results show that the performance of Q-OFDM is superior that conventional OFDM especially for high values of SNR. A maximum gain of 5 dB gain in SNR has been obtained in both AWGN and flat fading channels in Q-OFDM system over the conventional one. While 3 dB maximum gain has been obtained for the case of selective fading channel.

Power amplifiers (PA) are typically the most power-consuming building blocks of RF transceivers. Therefore, the design of a high-efficiency radio frequency power amplifier is the most obvious solution to overcoming the battery lifetime limitation in the portable communication systems. In order to obtain the maximum output power, the reference impedance (usually 50 Ohm) must be transformed to the optimum input and output impedance of the selected transistor. Matching networks are therefore necessary at the input and at the output of a power amplifier circuit. In this research we designed a class C power amplifier operates in frequency range (200MHz -500MHz) with input power 0.63watt and output power 10watt. At high radio frequencies, the spurious elements (like wire inductances, interlayer capacitances, and conductor resistances) have a significant yet unpredictable impact on the matching network. In our design the matching network for input and output is implementing for frequency range (300MHz-350MHz) because of the wide band frequency range for transistor used.

The number of wireless telephone subscribers has increased at an extraordinary rate as the mobile phone has become an important part of everyday life. The rapid adoption of handheld mobile phones, leads to a growing number of mobile base stations and a growing concern for their possible adverse effects on human health. This paper aims to assess the effects (if any) for the, low-level non-ionizing RF energy of cellular systems have on human health and to determine the safety limits needed to protect human health. The power density and the safety distance will be calculated at different environments for Global System of Mobile Communications (GSM) cellular system, and it will be compared with the standard applied limits. The founded that theoretical calculation of the power densities are much lower than the exposure limit that have been recommended by the international health organizations.

This research includes a theoretical analysis according to nonlinear Klein- Gordon equation to study the dynamic state of a specimen of an electric translation line in Iraq while it is in a galloping motion that results from: different wind velocity, material type, different tension force as well as the span between towers. This is in addition to knowing the behavior of the specimen under the effect of both the force that results from wind velocity and the altitudes formulated in the string due to the galloping motion. Reducing the effect of the galloping motion and compare it with the numerical method of a model with multi-degree of freedom by using the ANSYS workbench-12.1 is also taken care of in this work.The theoretical findings of the research have shown that they are very near to those of the numerical method; they have also shown that the material type and the length of the string are very important in determining the altitude of the galloping motion.

AbstractOne of the important steps for civil engineer in the construction sites the estimations of the earthwork and construction materials which may decrease construction costs. Conventional method for volume estimation includes methods of surveying using to acquisition data on site, plotting and calculation of volume. The search consist ground surveyed and land leveling to constructed building by fined the reduced level for all the points and selected the final elevation that leveling the ground .Two method Used to calculate the volumes. First method used points as across-sections to calculate the areas and volumes with (Excel 2003). Second method used points as Grid and calculates the volumes. The method accuracy depended on the shape of the project.

The thermal effect of the turbine blade film cooling and the penetration area of jets issuing at an angle into cross mainstream flow have been investigated numerically and experimentally. Experimental and numerical simulations have been introduced to simulate a discrete circle hole film cooling flow over a symmetrical airfoil representing turbine guide vanes surface. Several cases have been studied in the experimental work by using three-velocity ratio (0.5, 0.9, 1.3), and three different jet issuing angles, longitudinal injection angle (37.50 and 900) both with lateral injection angle (stagger angle = 00 and 450). Airfoil angle of attack has been changed during the experimental program throughout (00, 50, 100, and 150). Experimental investigations gave qualitative information about the penetration area and flow structure of the mixing flow at all cases and the results were used to verify the computation method and to select the best velocity ratios for the flow penetration, flow structure, and the thermal effect of cool jets.

Most structures in Iraq were designed only for gravity loads, these make buildings present a major quandary for the person or agency concerned with reducing earthquake hazards. Objectives of this research are to develop a computer program for the evaluation existing gravity loads buildings to identify any weak columns in the structure that should need retrofit according to value of damage index . Seismic retrofit techniques are previewed and discussed in this research . The results identify the location and severity of the damage member, indicate that the sever damage maybe concentrated in the upper stories and can possibly lead to further collapse. According to these results, a minimum retrofit should be considered to reduce the risk of structural collapse.

Weather forecasts and warnings are the most important services provided by the meteorological profession. Forecasts are used by government and industry to protect life and property and to improve the efficiency of operations, and by individuals to plan a wide range of daily activities. Many searches have been made in weather forecasting using Artificial Neural Network (ANN) output one weather temperature degree, which give a little indicator about the weather temperature. In this paper, two weather temperatures have been forecasted using Artificial Neural Network (ANN). The design of the ANN based on two previous weather temperatures degrees (high and low), as well as, the increasing and decreasing weather temperature degree according to thermal retention. The ANN design has been applied for Baghdad city, the capital of Iraq. The training and testing used meteorological data for three years (2007-2010).

The effects of wavy wall in asymmetric two-dimensional channel on flow and heat transfer have investigated in this paper. The flow and temperature fields are studied numerically with different amplitude to channel length ratio and different number of waves. The laminar flow field is analyzed numerically by solving the steady, two-dimensional incompressible Navier-Stokes and energy equations. The Cartesian velocity components and pressure on a collocated (non-staggered) grid are used as dependent variables in the momentum equations, which discretized by finite volume method, body fitted coordinates are used to represent the complex wavy wall geometry accurately, and grid generation technique based on elliptic partial differential equations is employed. SIMPLE algorithm is used to adjust the velocity field to satisfy the conservation of mass. The range of Reynolds number is (Re = 50 - 500). The results show that at high amplitude to wave length ratio and high Reynolds number the wavy channel is an effective heat transfer device and the heat transfer enhancement increases with increases the number of waves. Good agreement with the published available data is obtained.

This paper presents an Artificial Neural Network ( ANN) based technique for controlling external chopper resistance circuit in the rotor side of wound rotor induction motor(WRIM), for keeping the motor speed constant at the varied torque or keeping the load torque constant at the varied speed , which generates the exact chopper duty cycle for any given operating condition. Also the paper study current and torque harmonics analysis. The controller circuit was simulated and operated on both closed and open loops. Theoretical analysis is carried out for the controller drive system. Theoretically obtained results are compared with those obtained by ANN. All data which are used to train the network by a back propagation algorithm simulated in the MATLAB Neural Network Toolbox. The results obtained are satisfactory and promising. The advantages of this controller have the design simplicity and high accuracy.

The hydrodynamic behavior of air-lift type tube reactor (ALT reactor) was investigated in laboratory and pilot scale, established theoretical models were developed for the description of superficial liquid velocity in the recycle tube and of pressure losses in the reaction tube.Using different tube sizes for recycle and reaction tubes, the next parameters were measured under various operation conditions: superficial liquid velocity in recycle tube, pressure drop, real liquid and gas velocity, minimum and maximum gas velocity in reaction tube.The new theoretical models were proved on the base of measured data with a maximum deviation of 10%.

This paper deals with the development of computational model for fingerprint recognition. A person can be recognized and identified by comparing the characteristics of his fingerprint with those of known individuals. Features of the fingerprint under test are compared with a set of enrolled fingerprints already stored in database. If the features match with the database then fingerprint can be recognized and identified.The most popular technique is Minutia Extraction for Fingerprint. The development of computation model for fingerprint recognition by using slantlet transform instead of FFT due to the ability of the slantlet transform to decompose signal (images at various resolutions allows accurate extraction of features from non stationary signal images). The low frequency coefficients which contain the maximum information about the signal, were selected from slantlet decomposition, these coefficient fed to another step in Minutia Extraction and then to Minutia Matching. This new method of fingerprint recognition tasks with lower number of calculations. Hence it raises the algorithmic efficiency and reduces the execution time.

A systematic development of the analysis, design, and testing by simulation of a closed-loop speed control of separately excited dc motor drive system is described in this paper. The motor controlled armature voltage is supplied from a three-phase fully controlled bridge converter. Closed-loop control is analyzed by using transfer function techniques and the necessity of an inner current control loop is demonstrated. Designs of both a proportional and proportional-integral controllers are outlined by using transfer function technique. A soft starting concept is used to reduce the value of starting current. The feed forward loop is used to reduce the effect of load torque disturbances. The speed and current responses are also presented for load and no-load cases.

The effect of solution annealing treatment on the formability of three stainless steel alloys (AISI 321, GOST A917, and SAF 2205) has been studied. Properties obtained from tensile testing (strength, ductility, strain hardening index, and strain rate sensitivity) have been chosen as criteria to detect formability. The values of those criteria were compared with stretching behavior obtained from Olsen test (h-value). Solution annealing treatment, at the range 900-1350oC for 30 min. followed by water quenching, which showed a remarkable effect on formability for the three alloys. Annealing the duplex stainless steels at 950oC and at temperatures higher than 1050oC, was found to decrease the strain hardening index (formability) due to the formation of brittle phases during annealing at 950oC, and also due to increase of ferrite content when annealing at temperatures higher than 1050oC. The rate of cooling (water quenching, air cooling, and furnace cooling) after annealing at 1050oC showed to have an effect on the formability of the three alloys in a way that air cooling and water quenching produced better formability than furnace cooling due to formation of brittle carbides and grain growth during furnace cooling.

This work contains a general study about all epicyclic gear trains .This was accomplished by:-1.Developing simplified equations for the kinematic analysis of all epicyclic gear trains .This will be used for future steady state and dynamic analysis .2.Utilizing the developed equations as a model for solving the kinematics of all epicyclic gear trains .This can be applied in all complex gear trains by developing a new approach which is regarded as an equivalent system using an imaginary method . 3.Using the new equivalent method to understand the kinematics of all complex gear trains which are difficult to analyse . This is achieved by simplifying all complex gear trains into simple epicyclic gear trains by re-drawing the new equivalent system . The basic aim of this paper is to develop a new and simple learning technique in understanding and solving the kinematics of any complex gear mechanism . In addition , this approach might be useful in future design of complex gear mechanism .

The research aims to study the engine performance by using the pressure-crank angle diagramat differentengine speed for different fuel injection period in Direct injection diesel engine type (PETTER PHW). The present work also includes the calculating of the gas temperature of cylinder and other variables to determine the Optimum performance of the engine. Thepresent work also study the effect of several variablesi.e the effect of engine speed , fuel injection period , and the use of several models on the value of the cylinder gas temperature. The study showed at the speed (N = 1600 rpm) the engine performance can be optimized. The Ignition delay period increases with increasing engine speed. The results demonstrated that the Ignition delay period increases with the advance injection fuel angle. When using different models results showed that there are effectiveness on cylinder gas temperature curves between the first model (Single zone), and the other two ( Two zone, Multi zone).