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Basrah Journal for Engineering Science

مجلة البصرة للعلوم الهندسية

ISSN: Print: 18146120; Online: 23118385
Publisher: Basrah University
Faculty: Engineering
Language: English

This journal is Open Access

About

The Basrah Journal for Engineering Science (BJES) is an open access, peer-reviewed bi-annually journal (two issues per year) that aims at the publication of original research papers on the latest developments and techniques in the variety fields of Engineering science and their applications to the real world. The BJES is the Official journal of the Iraqi Ministry of Higher Education and Scientific Research issued by the College of Engineering, University of Basrah, Basrah, Iraq. The Submitted papers should be written in English, and all submissions should be made through the on line EDAS system. Papers may be theoretical (including computational), experimental or both. The contribution should be unpublished before and not consideration for publication elsewhere. BJES maintains a standard double-blind peer review process, which means that the identities of the authors and the reviewers are not known to each other. BJES is an Open Access Journal, which supports the rights of users to read, download, copy, distribute, print, search, or link to the full texts of these articles provided they are properly acknowledged by cited.

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Contact info

Address: Engineering College , University of Basrah ,Basrah, Iraq
P.O.Box: 801
Fax: 0188696
E-mail: bjes_editor@yahoo.com
Mobile No.: 07801419901

Table of content: 2016 volume:16 issue:1

Article
Implementation and Design of Fuzzy Supervisory Controller for Mobile Robot Manipulator

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Abstract

The Mobile Manipulator Robot (MMR) has many applications in different aspects of the life, for example, grasping and transporting, mining, military, manufacturing, construction, and others. The benefits of MMR rise in a dangerous place where the human cannot reach such as disaster areas and dangerous projects sites. In this work, the PID controller is combined with Fuzzy Logic Controller (FLC) to structure the Fuzzy Supervisory Controller (FSC) to overcome the drawbacks of PID controller and to obtain the advantages of FLC. Two approaches are suggested for the navigation of Autonomous Mobile Robot (AMR). These are; goal reaching fuzzy control (GRFC) and the obstacle avoidance fuzzy control (OAFC). The hardware implementation of the AMR is performed using AVR ATmega32 microcontroller, two DC motors, light dependent resistor (LDR) and five Infra Red sensors. While the Laboratory robot arm with some fabrications is used as manipulator's arm with a five degrees-of-freedom. Then a microcontroller is employed to implement the proposed controller for MMR. The designed MMR is tested in real environments and give a good navigation.


Article
Adaptive Control-based synchronization of chaotic systems with uncertain parameters and its application

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Abstract

This paper is concerned with performance on the widely used control technique: adaptive control for synchronization between two identical chaotic systems embedded in the Master and Slave. It is assumed that the parameters of slave system are unknown. The required stability condition is derived to ensure the stability of error dynamics. Adaptive control laws are designed using appropriate parameters estimation law. The system parameters are asymptotically synchronized; thus the slave parameters can be identified. As an application, the proposed scheme is applied to secure communication system. The information signal is transmitted and recovered on the basis of identification parameters also the system is tested under the consideration of the noisy channel. Finally, through Numerical simulation results, the proposed scheme was a success in the communication application.


Article
Effect of Loading Level and Span Length on Critical Buckling Load

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Abstract

An investigation was conducted to study the effect of loading level with respect to shear center and span length on lateral torsional buckling of steel I-section beams using linear and nonlinear finite element analysis available in ANSYS (version 12.0) computer program. The steel beams which have been studied included prismatic beams and linearly web tapered beams with web tapering ratio of (0.5). The maximum height of all beams was 300 mm with span length of 4, 6 and 8 m. The critical buckling loads for prismatic and linearly tapered cantilever and simply supported beams subjected to point load and uniformly distributed load were determined. The results showed that the bottom flange loading gives a buckling loads higher than that of the top flange loading with percentage increases of 148% and 155% for the linear and nonlinear analysis respectively for the prismatic beams. While for the tapered beams, these percentages increases were 61% and 67% respectively

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Article
Nonlinear finite element analysis of simply supported composite beams stiffened with steel channel

Authors: Alyaa H. Khalaf --- Abdalnassre M. Abbas
Pages: 22-27
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Abstract

A composite beam is an accumulation of different materials so as to form a single unit to exploit the prominent quality of these materials according to their position within the cross-section of the composite beam. The present study investigates the structural behavior of six simply supported composite beams, in which a reinforced concrete T-beam is connected together with a steel channel located at the bottom of a T-beam by means of headed stud shear connectors. The used degrees of shear connection are (100%, 75%, 50%, and 38%). Three dimensional nonlinear finite element analysis has been used to conduct the numerical investigation for the general behavior of beams which are subjected to central point load. ANSYS 12.1 program code was used to estimate the ultimate loads, deflections, stresses, strains, end slip. Concrete was modeled by brick element (SOLID65), while the steel channel was modeled as a brick element (SOLID45). Two-node discrete elements (LINK8) are used to represent the steel reinforcement and shear connectors. The perfect bond between the reinforcing rebars and the concrete was assumed. The load on beams was applied monotonically in increments up to failure. The reduction of the degree of shear connection from 100% to 38% causes increasing of strain, mid-span deflection and end slip with an average of 3.95%, 13%, and 111% respectively, while the ultimate load decreases with an average of 7.3%. In order to observe the efficiency of the 3-D model, a comparison was made with available experimental work. Good agreement was obtained throughout this work between the finite element and available test results.

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Article
Simulation of Salinity Intrusion from Arabian Gulf to Shatt Al-Arab River

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Abstract

This study is an attempt to determine the salinity intrusion from Arabian Gulf to Shatt Al-Arab River. One dimensional time-dependent hydrodynamics model coupled with salinity model were applied and solved numerically by using the explicit finite difference method, a computer program was used to simulate the flow and the salinity concentration. “Total tide” software has been used to get an information about tide level in the day of field measurement, field measurement of salinity and tide velocity in Al-Fao Station was taken for a full tidal cycle and compared with the program results shows a good agreement between field measurement and numerical model results. Three sections were taken along the Shatt Al-Arab River to study the effect of salinity intrusion from the sea. It were found that the effect of salinity intrusion from the sea, reach a distance of a few kilometers upstream of Shatt Al-Arab mouth, but not farther than Abadan region. It is found that the salinity increased rapidly in the last of tidal period to a distance approximately equal 50 km downstream of Karun river or 10 km upstream of Al-Fao, and reach gradually to the salinity of the sea


Article
Computerized Testing Machines to Study the Effect of Strain Rate on Mechanical Properties of CFRP

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Abstract

In this paper, a universal testing machine and an impact testing apparatus have been upgraded by using a high accuracy data acquisition and control system interfaced to a personal computer with proper sensors and actuators. The purpose of the upgrade is to increase the accuracy of the measurements and to perform advanced material testing procedures that are not possible with the old configuration. The modernization process not only permits the accurate data acquisition and convenient operation but also the ability to study the effect of strain rate on the tensile properties of materials. Also, an experimental study of the response of CFRP (Carbon Fiber Reinforced Plastic) material to low and intermediate strain rates has been carried out.


Article
Empirical Formula for Estimation the Sediment Load in Shat AL-Gharaf River

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Abstract

In this research, the sediment load in Shat AlGharaf River lies in the south of Iraq, has been studied. Two empirical formulas those have been presented by ; Bagnold and Van Rijn were adopted as a deterministic equations for computing the sediment discharge in selected reaches of the river . The application of these equations requires to do different hydraulic, sediment, and geometric measurements for the selected reaches. Accordingly , thirteen sections along the river within a study area have been adopted. After analyzing the available data, a new the formula for estimating the suspended sediment load in Shat Al-Gharaf was developed, depending on the data for ten sections of this river and by using SPSS program, the determination coefficient of the new formula was (R2=0.94). The validity of the established formula has been verified using some well related (i.e., nearly the same hydraulics and geometrical circumstances) of field data over the world was selected from published literatures [8] these are: Colorado river data of the U.S.B.R.(1958), River data from Leopold (1969) , and India canal data of Chaudry et.al.(1970). As well As those observed in the remaining three sections of present River, the verification shows a good agreement. The results of the adopted two formulas and the new formula were compared with field measurements using Discrepancy Ratio (bais) method. The suggested new formula gave the best results where 50% of data located within a discrepancy a ratio close to one and 30% of data located within an error ±20%, that is referred to suitability adoption this formula as a the deterministic equation to estimate the sediment load in Shat Al-Garaf river within a study reach


Article
Prediction of Groundwater Level in Safwan-Zubair Area Using Artificial Neural Networks

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Abstract

Safwan-Zubair area is regarded as one of the important agricultural areas in Basrah province, South of Iraq. The aim of this study is to predict groundwater level in this area using ANNs model. The data required for building the ANN model are generated using MODFLOW model (V.5.3). MODFLOW model was calibrated based on field measurements of groundwater level in13 monitoring wells during a period of one year (Nov./2013 to Oct/2014). The neural network toolbox available in MATLAB version 7.1 (2010B) was used to develop the ANN models. Three layers feed-forward network with Log-sigmoid transfer function was used. The networks were trained using Levenberg-Marquardt back-propagation algorithm. The ANN modes are divided into two groups, each of four models. The input data of the first group include hydraulic heads, while, the input data of the second group include hydraulic heads and recharge rates. Based on results of this study it was found that; the best ANN model for predicting groundwater levels in the study area is obtained when the input data includes hydraulic heads and recharge rates of two successive months preceding the target month, the best structure of ANN model is of three layers feed-forward network type composes of two hidden layers, each of ten nodes, and the including of recharge rates as input data, beside the hydraulic heads has improved slightly the results.


Article
Independent Control of Two-PMSM Fed by Two SVPWM Inverters with Fault Tolerant Operation

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Abstract

This paper presents an implementation of an independent control of two-mechanically coupled Permanent Magnet Synchronous Motor (PMSM) fed by two Space Vector Pulse Width Modulation (SVPWM) inverters in a separate mode and in the event of failure one leg of one inverter, fault tolerant mode. In a fault tolerant mode, the two motors can operate in an independent control strategy from one inverter with five legs to maintain a constant output coupled torque. The Field Oriented Control (FOC) strategy is used to control the stator current of the two motors through two separate paths. Such application is used in the field of a coupled torque produced by multi-motors such as in subway applications. The whole system is simulated in Matlab /Simulink and the simulated results show a stable and robustness a system which can maintain a constant developed torque with a velocity reaches to the rated under fault tolerant operation.

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Article
Best Arima Models for Forecasting Inflow of Hit Station

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Abstract

Time series analysis for hydrological phenomena has an important role in water resources engineering. In this study, seven models of ARIMA family are tested for forecasting the monthly discharge at Hit station on Euphrates river in Iraq. The statistical analyses were done for models with help of IBM SPSS statistics 21 software, The number of observations used is equal to 480 reading, start from October 1932 and end at September 1972, this period represents the near-natural stream flow of the river before the construction of dams in Syria and Turkey. Statistical tests such as T-test and F-test were used to detect any change in Mean and Variance at 95% significant probability level. Results showed that the best model is (2,0,1)×(0,1,1)12 which gives a minimum error and good agreement between observed and forecast discharge.

Table of content: volume:16 issue:1