AL-Rafidain Engineering Journal (AREJ)

Fuzzy logic controllers have been emerged as one of the most active and useful research areas in the field of fuzzy control theory. That is fuzzy logic controllers haven successfully applied for controlling various physical processes. This paper shows how fuzzy logic is used for position control application. Three types of Fuzzy Controllers are implemented and their position control response is measured. Two of them are FPI, FPD with two inputs (e ,∆e). The third controller is build via connecting the first two in parallel. Two dimensional rule bases, with seven memberships for both inputs and output, are used to perform the control action. Computer simulation is guided to illustrate the performance and show the result for the three types.

This study was conducted in two parts, A theoretical work consisted of-a full- design of the bottom of a moldboard plow, having, a cylindroidal type, using the usual philosophy of the design, then a Ruck-shape was added to the upper free- border,. Complete-stresses analysis of the model was conducted, in order to obtain the Von-Mises max stress and Tangential stresses using the finite element-Technique. The model was manufactured according to the specified, precession and dimension. The aim of the work was to evaluate the performance of the two types of mold board plows (designed and usual - 113), for comparison with three depths (15-20,20-25,25-30 cm) and with three forward speeds (3.484,6.353,9.818 km/hr), In the following the most important mathematical results: Designation indicators The designed moldboard plow recorded Von Mises stress and tangential stress on the bottom least than from the usual moldboard plow according to the finite element analysis.

In this research, a hardware digital circuit was designed for a programmable rotational stepper motor using VHDL as a design tool and the FPGA as a target technology. The design is implemented on a Spartan 3 starter kit (supported with XC3S200 field programmable gate array). The 50 MHz provided by the starter kit is divided to obtain the necessary delay time between the motor phases that ranges between 2-10 m seconds. Through output selections, the direction of rotation of the stepper motor besides the magnitude of the angle of movement and the rotation speed can be controlled. The advantage of using reconfigurable hardware (FPGA) instead of a discrete digital component is that the designer can make modifications to the design easily and quickly, and the total design represents an embedded system (which works without computer). The total programmable hardware design that make control on the stepper motor movement, occupy an area that did not exceed 12% of the chip resources

Wear is one of the problems that occur in the moving parts either by rolling or sliding. This work includes experimental study on the wear of low carbon steel. Three surface treatments were chosen these are cyaniding, solid carburizing and hard chrome plating. The wear test was made under dry contact condition for the treated and the untreated surfaces. A constant load and speed were used for two types of motion: sliding-rolling and pure rolling. An Amsler machine was used. The high carbon steel was chosen for making the upper specimen and the low carbon steel was chosen for making the lower specimen. The high carbon steel was hardened while the other was surface treated (carburizing, cyaniding). The hard chrome plating was also used to increase the surface hardness. It was noticed that increasing of surface hardness reduced the wear amount produced, and the cyaniding gave the highest resistance to wear whereas the hard chrome plating gave the lowest one, and the wear under pure rolling condition was small .It was found that the wear rate of treated surfaces is high in the first stage of the test then the rate decreases until it reaches a steady state and for both motions.

Token ring LAN’s have been used for many years and occupied an important part of the computer network world. It has the advantage of stabilized performance over variable load conditions. In this paper, a new method is introduced to enhance the characteristics of the LAN. The idea behind the new method is to give the stations on the ring more opportunity to transmit by splitting the main ring into mutiple subrings each one of them use the same protocol of the ordinary token ring LAN and managed by supervisor stations. Discrete event simulation is used to examine the effect of adopting the new method on the performance of the ordinary LAN(for simplicity of simulation, two subrings is considered in this research). The results obtained from the simulation program show the benefit obtained from the new method

In order to study and investigate the power quality problems, this research presents the methods of wavelet transform and fourier transform with comparison between them, and consitrate on multiresolution analysis wavelet transforn to analyse the waveform of electric power quality after inter, and monitor it on the display of personal computer to detect and localize power quality disturbances. Standard Deviation is taken as a criteria to classify this disturbances.This method provides more easy and accurate idea about power quality and its disturbances

Abstract The paper deals with study of affecting parameters on the communication performance and the coverage range of the cell, and thereafter on the efficient coverage of the intended area. The coverage starts within the basic unit (the cell), by estimating the affecting parameters on the signal power level in the uplink and downlink at the worst practical circumstances (the mobile station at the cell boundary, or in a high fading region), taking into consideration the factors causing fading and other losses is the signal power.

Abstract The Islamic house conceders the basic building unit of the society and the basic formation of the city fabric. Islam has tended to stabilize the morals and spirituals constructive of the house, according to the words of the Prophet (the Muslim home blessings and peace be upon him). problem of the search Lies in the presence of a gap between the ordinances and the rules of Islamic house, and the contemporary housing which noticeably rose the proportion of non-approval housing with the Shari in the most cities of Islam, including both (the glamorous housing and destitute housing which lost its simplest means of a dignity life), one of the reasons for this disparity is the absence of a clear perception of society and the designer about the criteria of the Islamic house. research aims to clarify concepts and morals which came in the Holy Qumran and the Sunni of the Prophet, then offering derived provisions showing its impact on the contemporary design standards .Ends by offering new standards and dwelling concepts derived from the Islamic religion, hoping that God tolerates and leads for later research in the areas of design and implementation. To promote Central Islamic housing (not forsake nor excessive).

This paper is an attempt to design and implement MAC (multiply-accumulate) units for pipeline DSP architectures on FPGAs. An application has been chosen to evaluate the results of the architecture. Results show that these units are applicable and can be used by the developers especially by the lifting based discrete wavelet transform.

Abstract In this paper, an experimental flume study was carried out on riprap gradation effects on local scour around bridge piers under clear water condition . Experiments were performed on circular and semi-circular piers having diameters and widths of (57, 90, 140) mm, respectively. Five mixtures of riprap were used having different gradations and the same mean grain size of (2.83) mm. The approach depth was maintained constant for all discharges which ranged between (16) l/s to (24) l/s . Experimental results indicated the importance of riprap gradation around bridge piers and that it is an important factor on its stability. Furthermore a formula for determining Froude number (Fro) at the threshold of riprap failure in terms of the variance of riprap, , the ratio between pier width to the average flow depth (b/y), and pier shape factor (k), with (R2= 0.82) was obtained.

Abstract It is important to study Syme socket structure with respect to its strength. Due to the end stump deformity of the Syme’s amputee, socket must has an opening (cutout) provided either posteriorilly or medially depending on the experience of the technicians. This work is carried out numerically and experimentally to find out which side of socket, the opening should be provided, and to know the best shape should the opening have; rectangular or circular shape. Numerical solutions have proved that the posterior opening is more desirable than the medial side opening, While rectangular shape of opening is better than the circular one. In order to verify the obtained results, two similar models are constructed having different location of opening. The two sockets tested experimentally using strain gage technique

Abstract A solution method is developed to obtain three-dimensional velocity and pressure distribution within a centrifugal pump impeller. The method is based on solving fully elliptic partial differential equations for the conservation of mass and momentum by finite difference method to convert them into algebraic equations. The effect of turbulence introduced using a certain algebraic model based on modified Prandtl’s mixing length theorem. The conical coordinate system is used in order to fit an arbitrary hub-to-shroud shape. The set of algebraic equations is solved simultaneously by “SIMPLE” algorithm to obtain velocity and pressure distribution within the impeller passage. The results are compared with previous experimental results of other researcher under the same operating circumstances and acceptable agreement has been found.

In this paper, a single plane balancing method based on vibration amplitude readings only, has been adopted. This method is discussed in detail, including an analytical basis and a practical implementation procedure. Four runs of trial mass are required to determine the vibration amplitudes when a calibration mass of fixed value is placed in four different positions, each position being advanced ( ) from its previous position. An experimental test rig is built and prepared to obtain the vibration measurements necessary to be fed as an input data to a written computer program, which calculates the magnitude and location of the weight required to balance the test rig rotor the. For the present study, the adopted method was successful and permitting safe operation for the rotor disc through its running speed.

This research aims to study the effect of utilization of industrial waste/lime (by-product of sugar factory) on some engineering properties of clayey soil selected from Mosul city. These characteristics are unconfined compressive strength, permeability, soil-water characteristic curve and Durability. The tests were performed at different percentages of lime (2, 4 and 6) % and industrial waste/lime (2, 4, 6 and 8) % by dry weight of soil. Results showed a decrease in the plasticity, swelling pressure and swelling potential of treated soil. The soil became non plastic at optimum lime, waste lime contents of (4, 6) % respectively. Unconfined compressive strength (UCS) increased with increasing of curing time and stabilizer contents and reached a maximum value at optimum stabilizer contents. The (UCS) of soil stabilized with industrial waste lime was more than that stabilized by lime at different curing times. Durability tests (immersion and slaking) showed that the treated soil with lime was more durable than that treated with waste lime. The Permeability of treated soil was found to be more than that of natural soil. On the other hand, the permeability of soil treated with waste lime was more than that of treated by lime at different curing time and it reached a maximum values at (4, 2)% for the soil treated with waste lime and lime respectively. The soil-water characteristic curve showed that the soil ability to hold water increased with increasing lime and industrial waste contents.

Abstract The present study investigates the potential of Radial Basis Function (RBF) neural networks for the prediction of reference evapotraspiration (ETo). The study utilizes daily climatic data of temperature, relative humidity, sunshine hours, wind speed, and rainfall for five years collected from Mosul meteorological station, north of Iraq. Thirteen RBF networks each using varied input combination of climatic variables have been trained and tested. The network output is compared with estimated daily Penman-Monteith ETo values. To evaluate the performance of RBF networks, the same networks in the studied cases were re-trained using the well-known feedforward-backpropagation (FF-BP) networks. In addition, the effect of including a time index within the inputs of considered networks is investigated. The study shows that the RBF network is seen to emulate the FF-BP in its performance and can be effectively used for ETo prediction. Besides, it is much easier to built and much faster to train. It is noticed that the networks’ output are very highly correlated to estimated ETo, especially when concerning all the climatic parameters. The study results reveal that adding a time index to the inputs highly improves the ETo prediction of the studied cases.