Print ISSN: 1681-6900

Online ISSN: 2412-0758

Volume 32, Issue 4

Volume 32, Issue 4, May 2014, Page 148-1082


Appraisal Criteria-Space in Some Residential Urban Areas for Al-Kut City

Riyad Al-Anbari

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 800-811

In this paper, appraisal for residential environment type in Al-Kut city has been done by regular process for evaluation of 198 random samples from dwelling units have been selected in four districts: Al-Kafa'at (57 samples), Hay Al-Rabee (57 samples), Al-Hoboken (65 samples) and Al-Shown (19 samples) to represent the factual residential environment for all the city. Questionnaire form has been prepared consists of (26) questions for environmental aspects for dwelling units to ensure getting all information (quantity and quality) required for environmental appraisal method approved by (APHA). Another one prepared for outdoor environment that surround the dwelling units areas, consists of (21) questions.
Results had been indicated that residential environment for Al-Kut city suffers from many problems like overcrowding which appears in some dwelling units. All then coming from increasing in number of families and total habitants which cause reducing the require areas for residents and led to reduce the privacy. Also some of the dwelling units had toilet and bathroom located outside its structure, additionally lack to some basic environmental requires. As result the shutdowns of public electricity for a long duration per day generate lack in adaptation, light…..etc. Surrounding environment of some districts has other important factors like neglecting or poor pavement of its streets and sidewalks. In addition to lack in sewage and storm systems, public parking, open areas, public playgrounds and public playfields.

The New Ternary Ceramics of MAX Phases, the Solution of All Obstacles (Theoretical and Experimental Review)

Ahmed M. H. Abdulkadhim Al-Ghaban

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 812-821

In the recent years the new ternary carbides or nitrides materials with the formula of Mn+1AXn where M is a transition metal, A is an element from group IIIA or IVA, X is either Carbon or Nitrogen, and (n=1-3) have been given more attention due to their unusual set of mechanical and physical properties. In this manuscript types, properties and some very new applications of these so called MAX phases in bulk and thin films forms have been reviewed. Some experimental results are also given. This research may shed light on these materials to be candidates for many potential applications.

Assessing the Dynamic Behavior of Asphalt Stabilized Gypseous Soil

Mahmood D. Ahmed

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 822-841

The study presents the test results of stabilizing gypseous soil embankment obtained from Al- Faluja University Campus at Al-Ramady province. The laboratory investigation was divided into three phases, the physical and chemical properties; the optimum liquid asphalt (emulsion) requirements (which are manufactured in Iraq) were determined by using one dimensional unconfined compression strength test. In the first phase , the optimum fluid content was 11% (6% of emulsion with 5% water content). At phase two, the effect of aeration technique was investigated using both direct shear and permeability test. At phase three, a laboratory soil model of dimensions 50x50x30 cm was used as a representative of gypseous soil; pure soil, and asphalt stabilized soil have been compacted in five layers after practicing an aeration technique at maximum dry density (modified compaction) cyclic loading test was carried out on four gypseous soil models, two of them were pure soil under (dry and absorbed condition), and the other two were stabilized with emulsion also under (dry and absorbed condition). The impact of charging the hydraulic conductivity due to asphalt stabilization was investigated and the vertical deformations were determined using LVDT.
For the pure soil in dry condition the vertical settlement at the top surface was (7.45 mm) at (157 load cycles), while for pure soil model under absorbed condition, the water was raised to the surface in three days , so the vertical settlement at the top surface was (12.5 mm) at (29 load cycles), this means that the pure gypseous soil under absorbed condition show reduction in strength by(85%).
When the stabilized soil is in dry condition, the vertical settlement at the top surface was (9.75 mm) at (911 load cycles), while the soil was stabilized and subjected to water absorbed for seven days. The water stopped rising at second layer which is the same inlets level from the bottom, and the vertical settlement was (10.47 mm) at (897 load cycles), so there is no change in strength at failure.

Blind Detection Method of MIMO – Space Time Coded Wireless Systems Based on ICA

Wafaa Mohammed R. Shakir AL-Dahan

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 842-854

This paper presents a proposed blind detection method for Multiple Input Multiple Output-Space Time Coded (MIMO-STC) wireless systems based on Independent Component Analysis (ICA). The proposed method used the statistical independence of the sources of signals for blindly detection of STC signals. The original transmitted signals are estimated by gradient the kurtosis-based objective function of the received signals. In contrast to other approaches, the proposed method does not require any modification in transmission side or using the training sequences. Simulation results using MATLAB demonstrate competitive results for the proposed system comparing with conventional Minimum Mean Squared Error (MMSE) detector. Where at (10-7) Bit Error Rate (BER) there is about (4 dB) and (7.5 dB) improvement in Signal to Noise Ratio (SNR) for the proposed system adopting Orthogonal Space-Time Block Coded (OSTBC) scheme with (6) receiving antennae comparing to the same system with (4) and (2) receiving antennae respectively.

Evalution the Load Distribution Factors for Horizontally Curved Composite Concrete-Steel Girder Bridges

Eyad K. Say hood; Nisreen S. Mohammed; Ibtihal Fadhil Ali

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 855-872

In this research paper, a 3-D finite element model was used for the analysis of curved concrete slab on steel girder bridges. A parametric study was carried out to calculate the load distribution factors for horizontally curved steel I-girder bridges based on (AASHTO LRFD) live loads .The bridges are analyzed by three dimensional finite elements using SAP 2000 software (Structural Analysis Program) with shell elements. The parameters considered in this study were: span-to-radius of curvature ratio, span length and the analysis of bridge will be performed for the case of full live load and partial live loads. The full data are given together with AASHTO LRFD calculations up to L/R equal to (0.6).

Time Domain Simulation of Wind Shear and Tower Shadow in Wind Turbines

Farouk O. Hamdoon; Mohammed I. Abu-Tabikh; Mauwafak A. Tawfik

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 873-885

This paper presents an aerodynamic analysis of a three-bladed wind turbine using unsteady Blade Element Momentum (BEM) method. A MATLAB code has been written to perform the analysis in which a simulation model for a wind speed acting on a wind turbine rotor plane was used considering the effect of wind shear and tower shadow. Results obtained from the analysis have proved that tower shadow and wind shear contribute to periodic fluctuations in loads and mechanical power of a wind turbine .The frequency of the periodic fluctuations is n times the blade rotational frequency p, where n is the number of blades. For three- bladed wind turbine, this inherent characteristic is known as 3p effect. Furthermore, as the aerodynamic loads change periodically due to wind shear and tower shadow, this may have a large effect on output power quality and fatigue life of the blade. Hence, the loads analysis in this paper may be applicable to the improving power quality and design analysis of the wind turbine.

Evaluation of Flow Parameters around Tracking Solar Collectors with Different Collector Geometry and Different Operation Conditions

Khalid Hameed Hussein

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 886-907

In the current study, the flow parameters around the tracking solar collectors were evaluated. Different site conditions with different tracking solar collector's geometry are combined and investigated. Site conditions included different wind loading due to different angles of attack and wind velocity. Collector's geometry included dish collector, parabolic trough collector and Heliostat collector. The flow parameters are estimated numerically by using a suitable computational fluid dynamics (CFD) package (ANSYS FLUENT 14) to solve the governing equations and boundary conditions. The verification of numerical results was done by comparing the numerical results with experimental results of the case of parabolic trough solar collector. The results of wind loading on all types of collectors and flow characteristics at different operation conditions are obtained and compared.

Durability of some Weak Rocks Selected from Nineveh

Mohammed K. Faris; Amina. A. Khalil; Suhail I. A. Khattab

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 908-921

Some rocks are naturally weak, or it becomes weak due to weathering. Durability of weak rocks is one of the most important engineering properties to be evaluated. This study aims to determine the decrease of strength over time due to weathering processes for some weak rocks selected from four different locations within Nineveh. Rock samples were prepared for all types of selected rocks according to American Society for Testing Materials (ASTM) and International Society for Rock Mechanic (ISRM). Physical and mechanical properties of the samples were studied (dry density, absorption, Uniaxial compression test, Brazilian test, Point load test, and Slake–Durability test) in both dry and wet conditions. Slake - durability test used to determine the decrease in strength and weight loss% for studying rock samples using distilled water for all selected rock samples. Baghdad street and Talafare rocks samples were subject to a solution containing solute hydrochloric acid with 5%, and 10%, concentrations.
Results show that rock samples taken from Hay-AL-Quds and Hay-AL-Arab can be classified as very weak to weak with low durability, and weak with medium-high durability for samples selected from Baghdad street and Talafar. Results also indicate that there is a reduction in strength of treated rocks due to an increase in the level of weathering of rock. Higher values of reduction pointed out for samples treated with solute hydrochloric acid compared with the case when using distilled water with less effect in 5% concentration than that 10% concentration.

Study the Effect of Surface and Internal Heat Treatment on Mechanical Properties of C40 Steel Alloy

lamyaa kalel; Ahlam Abd Alamer Al khafaji; Sabah N. Mahmood

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 922-931

The research aims to study the effect of quenching, tempering and laser surface treatment on the mechanical properties of C40 steel. The steel specimens were heated to a temperature of 860°C, soaked for 60 minutes and quenched in oil and then tempered at different temperatures (100,200,300,400,500,600,700) °C.
Laser hardening were carried out by using Nd: YAG laser with different pulses up to 5 pulses, the applied laser energy was 500 mJ.
The mechanical tests such as: impact test and microhardness, were carried out for the specimens before and after heat treatment. Microstructure evaluation was carried out using computerized optical microscope. The results showed an improvement in the internal and surface properties of the metal.

Effect of Alloying Elements (Mo and Al) on Biomaterials Ti-Ta Shape Memory Alloys

Fatima J. Al-Hassani; Emad S. Al-Hassani; Sahib M. Al-Saffar

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 932-951

Titanium-Tantalum shape memory materials have widespread potential in biomedical applications In this research the alloy of (Ti-Ta) has been prepared by powder metallurgy technique use fixed percentage of Ta (30 at%), then the alloying elements (Mo and Al) has been added in different compositions (1 at%, 2 at% and 3%) to the master alloy (70% Ti -30% Ta) in order to improve corrosion resistance and mechanical properties . examination were done by using XRD, SEM technique, DSC, Vickers hardness, the porosity percentage and corrosion rate in different solutions (artificial saliva, Ringer solution and blood plasma).The XRD and microstructure results show that all samples with and without additives consist of two phases (β-phase) and (α-phase) at room temperature and the addition of Mo and Al in these percentages does not have effect on present phases. he transformation temperature decreases with the increasing in Mo percentage while this temperature increase with the increasing in Al percentage. The addition of Mo and Al leads to lower the hardness except 3% Mo this sample has highest value than the master sample. The porosity percentage decrease gradually with the increasing in the both Mo and Al percentage due to the better inter diffusion caused by these additives. From the corrosion results in 3% Mo the alloys have less corrosion rate than the master or other percentage (1 at% and 2 at %) In all solutions (artificial saliva, simulated body fluid( Ringer solution) and blood plasma) but the Al has a good corrosion rate in (artificial saliva and blood plasma).

Improvement of Iraqi Red Kaolin as a Refractory Material

Amel S. Merzah; Younis Muhsin; Yasamin k. Mahmood

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 952-959

In this work refractory material was prepared from Iraqi red kaolin with the addition of different proportions of silica and alumina (10, 15, 20 %) for each one and the red kaolin 70%. The powders were mixed in a ball mill, sieved, formed, dried at 110 oC for 8 hrs and then fired at different temperatures 800, 900, 1000 and 1100oC for 2 hrs. The physical properties(linear and volumetric shrinkage ,apparent density and porosity) were calculated from the measured data .It was found that the higher the firing temperature the better the properties of the prepared samples for a given mixture ,the best properties obtained in this work was 70%red kaolin,10%silica and 20%alumina).

Singularity Analysis of Parallel Robot with Six Degrees-Of-Freedom of Six Legs

Hassan M. Alwan; Hayder Sabah Ahmed

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 960-972

This paper suggests a mathematical solution to parallel manipulator with six degrees of freedom and follows the movement on a specific track to evaluate the singularity position. Mathematical equation was derived based on the fundamental principles of the coordinate and orientation vectors of the moving platform center.
According to this equation, each leg length was calculated. It means that the independent coordinates (linkage length) was calculated with respect to the dependent coordinates (coordinate and orientation of the moving platform center) by using (MathCad 14) software.
By solving the forward kinematics, the coordinate and orientation of the moving platform center were evaluated when this center was moving in a specific track. The center of moving platform moved between two points.
When the robot moved using animated program turns the moving platform to imaginary at (position 4), when lose control of the robot and this is a big problem occurs in special cases when the movement of the robot is called singularity.

Design of a Nonlinear PID Neural Trajectory Tracking Controller for Mobile Robot based on Optimization Algorithm

Khulood E. Dagher; Ahmed Al-Araji

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 973-985

This paper presents a trajectory tracking control algorithm for a non-holonomic wheeled mobile robot using optimization technique based nonlinear PID neural controller in order to follow a pre-defined a continuous path. As simple and fast tuning algorithms, particle swarm optimization algorithm is used to tune the nonlinear PID neural controller's parameters to find best velocity control actions for the mobile robot. Simulation results show the effectiveness of the proposed nonlinear PID control algorithm; this is demonstrated by the minimized tracking error and the smoothness of the velocity control signal obtained, especially with regards to the external disturbance attenuation problem.

Best Path Planning Algorithm for Mobile Robot Based on Modified Genetic Algorithm

Nadia Adnan Shiltagh; Kais Said Ismail; Zeyad Qasim Habeeb

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 986-1006

In this paper a best path planning for mobile robot based on modified Genetic algorithm is introduced. The proposed algorithm read the map of the environment which expressed by grid model and then attempts to create an optimal or near optimal collision free path. No mutation operator is used in the proposed algorithm and modified generations of population size with modified selection operator are used. The proposed approach is implemented in five different environments. Four of these environments are implemented in different range of space. The fifth environment is very large size. The simulation results show that the proposed method can give good results in terms of minimizing distance and executions time in comparison with the other Genetic algorithms and with other kinds of soft computing (Neural Networks and Fuzzy) when they applying with different environments and cutter environments.

Behavior of Plate on Elastic Foundation under Impact Load

Mohammed Y. Fattah; Mohammed J. Hamood; Sura A. Abbas

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 1007-1027

In this study, nonlinear three-dimensional finite element analysis has been used to conduct a numerical investigation of the effect of applied impact load on the foundation based on sandy soil using the finite element method by ANSYS (Version 11) computer program. The 8-node brick elements are used to represent the concrete of foundation and the soil under the foundation which are denoted by Solid 65 for concrete and Solid 45 for the soil and the interface is modeled by using three-dimensional surface-to-surface (Target 170 and Contact 174) contact elements connected with concrete and soil. As a case study, a concrete foundation with dimensions (3×3×0.3) m placed on the soil 15 m deep and 9 m away from the edge of foundation is subjected to impact load. A parametric study is carried out to investigate the effect of several parameters including: foundation dimensions (geometry) and amplitude of impact load.
It was concluded that as the foundation thickness increases, the time for maximum displacement to take place increases due to geometrical damping induced by the foundation. When the length of foundation increases, the oscillation of vertical displacement decreases, which means that the foundation becomes more stable.

Single Sand Column Stabilized by Lime Embedded in Soft Soil

Ahmed S.A. Al-Gharbawi; Hasan H. Joni; Namir K.S. Al-Saoudi

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 1028-1037

The behavior of isolated sand columns stabilized with lime and embedded in bed of soft soil of untrained shear strength cu between 16 – 19 kPa, is investigated. Holes in the form of columns 50 mm in diameter and 300 mm in length were excavated in a bed of soil and backfilled with sand mixed with various percentages of lime and cured for 7 days. A rigid circular footing 64.6 mm in diameter was placed on each column and loaded axially up to failure. The analysis of the model test results showed encouraging improvements of the load carrying capacity of the columns and significant reduction in the settlement over the conventional stone columns.

Effect of Holes Arrangement on Effusion Cooling Performance

Muwafag Sh. Alwan; Reyadh Ch. Al-Zachary

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 1038-1052

The present work concentrates on the experimental investigation of effusion cooling performance for different whole pitch ratios. The film cooling effectiveness and local heat transfer coefficient for difference jet holes arrangement have been investigated on a flat plate at three blowing ratios (0.5,1.0 and 1.5) at Reynolds number based upon hole diameter and hot main stream velocity is (6000). The investigations were done by using a single test transient IR the rmography technique. Three models of staggered holes arrangement are investigated. Each model is provided with seven rows of holes. The holes diameter (D) is 4mm, the longitudinal distance (X) are 8D, 10D and 12D respectively, and the span wise distance(S) between two neighboring holes are 7D.The attitude of the holes is fixed at inclination angle (θ= 30º). The experimental investigation shows that the thermal performance decreases as the pitch ratio (X/D) increases for all blowing ratios, and the film cooling effectiveness decreases as the blowing ratio increases for all the three models.

The Performance of Oxidation Pond for Wastewater Treatment in Rural Areas a Case Study “Al-Dewaniyah Province"

Mohammed Ali I.Al-Hashimi; HayderTaleeHussan

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 1053-1070

This research is concerned with study and checks the suitability of waste oxidation ponds (WOP) for treating wastewater in Al-Dewaniyah province by taking a sample of community of 10000 populations.
Experimental work had three cases depending on many considerations such as economical and specification of final effluent. A model of two ponds (facultative and aerobic) in series was used as first case of experimental work. Then third pond with aeration process to aerobic pond were added to the series as second case to improve the effluent. At last, sand filter was used to polish the final effluent from aerobic pond.
The three ponds had the same surface area (5.75m*2m) but with different depths, where it was 2m for anaerobic pond, 1.5m for facultative pond and 0.75m for aerobic pond. From the tests taken for the three cases, the results obtained for the last two cases were much better when compared with first case. In the experimental work a sand filter used for algae removal. Sand filter contributed in improving final effluent by decreasing total suspended solid (TSS) also in increasing removal efficiency of biochemical oxygen demand (BOD) and chemical oxygen demand (COD).At the end, the results of this work could be an invitation to use waste oxidation pond for wastewater treatment in rural areas or even small communities in Iraq but it may need more examinations to get best results.

Studying Abrasive Flow Machining Conditions by Using Taguchi Method

Abbas F. Ibrahim; Saad K.Shather; Wissam K. Hamdan

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 1071-1082

Abrasive Flow Machining (AFM) process can not only promote product’s inner surface quality but also economize the labor cost. However, the issue of inner surface quality includes not only the surface roughness but also the geometric variability before/after the AFM process. Based upon the experimental data of the effects of AFM process parameters, e.g., length of stroke, extrusion pressure, number of cycles, percentage of abrasive concentration, and abrasive grain size, Taguchi experimental design concept, L18 (61×34) mixed orthogonal array, is used to determine the S/N ratio and optimize the AFM process parameters. The statistical model could predict about 91.39%, and 96.4% for surface roughness (Ra), and material removal respectively. Length of stroke was more effect on surface roughness while percentage of abrasive concentration was more effect on material removal.

Studying the Process of Rising the Performance of the Cooling System by Using the Two Liquids R-12 &R-134a

Ayad Kadhim Khlief

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 148-164

In this research, has been studied the possibilities of replacing the refrigerant R-12 by R-134a and compare their thermal performance when working with the following variables (air cooling condenser, water cooling condenser, changing the length of the capillary tube).
The results shows that in the system worked with refrigerant R-12 and air or water cooled condenser the decreasing of the length of the capillary tube from 1.92m to 1.44m will lead to increase the coefficient of performance ,whereas the increasing of the length to 2.4 will lower the coefficient of performance .As For R-134a and air or water cooled condenser the decreasing of the length of the capillary tube from 1.92m to 1.44 will decrease the coefficient of performance. While the increase of the length to 2.4m will lead to increase the coefficient of performance.
That replacing the refrigerant R-12 by R-134a requires changing the compressor and oil used to stability the work of the cooling system. The results also show that replacing the refrigerant with air or water condenser and using the two lengths 2.4m and 1.92 will lead to increase of the coefficient of performance .The length 1.44m is working to decrease the coefficient of performance.