Print ISSN: 1681-6900

Online ISSN: 2412-0758

Issue 8,

Issue 8


Strength Improvement of Soft Soil Treated Using Stone Columns

Mohammed Y. Fattah; Mohammed A. Al-Neami; Ahmed Shamel Al-Suhaily

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1740-1756

A total number of 12 models tests were carried out on models of soft clays of different values of undrained shear strength varying from 8 to 18 kPa. The tests consist of twelve models of stone columns, single column, two-column group, three-column group, four-column group, five-column group and six-column group, in addition to one model of untreated soil.
The undrained shear strength has been measured using portable vane shear before testing and after failure of model. It was noticed that the undrained shear strength of model stone columns increased by about (5.6 -20) % due to the construction of stone columns. The provision of stone column in soft clay bed caused an increase in the bearing capacity of the foundation bed by (1.76 - 2.91) times for floating stone columns and (2.13 – 3.15) times for end bearing columns.

The Influence of Quenching Media and Aging Time on Microstructure and Mechanical Behavior of 6061 Aluminum Alloy

Naser Korde Zedin

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1757-1770

Aluminum-magnesium-silicon (Al-Mg-Si) alloys are medium strength, excellent formability, good corrosion resistance and widely used in extruded products and automotive body materials. The influence of quenching media with different aging time on microstructure and mechanical properties of 6061 aluminum alloy was investigated. The results show formation of (Mg2Si) and (CuAl2) phaseswhensolution treatmentwas applied (at 520°C for 2h,followed by quenching in water and oil at room temperature then aging (at 175°C for 2, 4and6h)) which resultimprovingof both the strength, hardness and decreases elongation. It can be noted that, the grains of samples which are quenching in water is finer than the structure of samples which are quenching in oil. The values of yield stress and ultimate tensile strength decrease respectively with increasing aging time to 6h as (258MPa) and (264MPa) for water quenching and (199MPa) and (235MPa) for oil quenching. In this piper were measured and discussedthe variation of the yield stress, ultimate tensile strength and elongation with different solution quenching and aging time.

Datum Transformation with the Minimum Curvature Surface Interpolation Approach

Ghydaa A. Abdul-Rehman; Abbas Zedan Khalaf

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1771-1784

This paper investigates main and important problem related to coordinates systems of Iraq. Maps of Iraq referenced to a local geodetic system while the technique oflocation observation and map production use the world geodetic system (WGS84) as a base reference datum. So, it has become necessary to find an algorithm to convert between Iraq local geodetic system (Karbala79) and world geodetic system (WGS84) simply because the (WGS84) is adopted globally and all of GPS and GNSS use that datum to calculate positions.
The idea of this paper came to create a mathematical model that relates between old and new datums by programing new software with matlab that perform the conversion with low coast, accurate and rapid procedure. In this paper modern approach was used to convert between (Karbala79) and (WGS84) it is:-
Minimum curvature surface interpolation via geodetic coordinates approach, this approach was used in USA by National Geodetic Survey (NGS) and it is requires a set of common points of two different datums.Computer software (IRAQCON) were developed with matlab 2013.
Precision of (0.03) meters in ∆E and (0.02) meters in ∆N were obtained from this approach when converted between datums, represent very precise result. Furthermore, field tests were done for this approach in ThiQar city. The tests were accomplished sucsussfly. It can be recommended forconversion system and production large scale maps for Iraq.
This work aims to develop and evaluate the best fit mathematical model of the existing control network system of Iraq to the WGS84 system

A Study of the Effect of (Cutting Speed, Feed Rate and depth of cut) on Surface Roughness in the Milling Machining

Ahmed Basil Abdulwahhab

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1785-1797

The purpose of this research is to investigate the effect of the main factor of the surface roughness in aluminum alloy (Al-2024) as a workpiece and face milling machining by using computer numerical controlled milling machine with 50 millimeter diameters of the tool with triple cutting edges of carbides. The controlled factors were the speed, feed rate and the depth of cut and this factors effect on the surface roughness. The result of the tests showed that the surface roughness was likely to reduce when the cutting speed increase. It is found the surface roughness is increase with increasing both of feed rate and depth of cut. then drawing a charts illustrate the relationship between variables (cutting speed, feed rate and depth of cut) with surface roughness and analysis resulting data by utilizing the SPSS software to predicted surface roughness by using milling machining parameters and graphical analysis of the obtained data, The percentage of accuracy was 96%.

Sub-Cooling Auxiliary System for Performance Enhancement of Main Refrigeration System

Mustafa W. Hamadalla; Fawziea M. Hussien; Ahmed J. Hamad

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1798-1812

In presentwork, a sub-coolingauxiliary system is integrated with vapour compression refrigeration system to predict the performance characteristics and energy saving of the system. An experimental investigation was performed to determine the performance parameters at various operating conditions using two types of refrigerants, R-134a and zeotropic mixed refrigerant R-404A.Investigating the results hasshowed that, the enhancement in performance of the refrigeration system with sub-cooling circuit compared with that for system without sub-cooling for R-134a was about 5% increase in RE, 14% optimization in COPand 2.8% energy saving for different thermal loads applied on the evaporator.While for R-404A, the increase in RE was 4%, the optimization in COP was about 13% and 3.7%energy saving. There is a significant improvement in the performance of the system with R-404A compared with that forR-134a at the same operating conditions.

Behavior of Reinforced Lightweight Concrete Two Way Slabs Strengthened With CFRP Sheets

Mazen D.Abdulah

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1813-1829

The principal objective of this paper is to investigation experimental and theoretical of flexural behavior of reinforced light weightconcrete two-way slabs strengthened or repaired with externally bonded carbon fiber reinforced polymer (CFRP) sheets. The experimental work includes testing of eight reinforced concrete slab specimens with dimensions (1050mmx1050mmx600mm), five of these slabs were strengthened, three slabs were repaired with carbon fiber reinforced polymer (CFRP) strips and one specimen was tested without strengthening acts as reference slab (control) for comparing the performance of CFRP strengthened or repaired slabs. The experimental variables considered in the test program include the quantity and shape of CFRP sheets. All the reinforced concrete slab specimens were designed of the same dimensions and reinforced identically to fail in flexure. All slabs had been tested in simply supported conditions subjected to central concentrated load.The experimental results show that the ultimate loads are increased by about (7-45%) for the slabs strengthened with bonded CFRP sheets with respect to the unstrengthened reinforced concrete slab (control slab). Three-dimensional nonlinear finite element analysis has been used to conduct the numerical investigation of the general behavior of strengthened slabs. ANSYS (Version 13.0) computer software was used in this work.Eight-node brick elements (SOLID65) are used to represent the concrete and three dimensional shell elements (SHELL 41) are used to represent the CFRP strips in the finite element analysis model. Perfect bond between the concrete surface and the bonded CFRP sheets is assumed.

Adaptive Polynomial Fitting for Image Compression Based on Variance of Block Pixels

Riyadh Jabbar S. Al-Bahadili

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1830-1844

This paper presents a proposed method to compress images using two polynomials with different models based on the value of block pixels variance. These two polynomials are chosen from different set of models, which give low number of coefficients and preserve the quality of image as much as possible. This procedure of adaptive fitting ensures that the number of coefficients for each block is as the minimum as possible depending on the value of block variance. After applying multi-level of scalar quantization and Huffman encoding to polynomials coefficients for each block of image and testing different variance thresholds; mean square error (MSE), peak signal to noise ratio (PSNR), processing time, and compression ratio (CR) are evaluated for two types of images (color and gray scales) and for different block sizes (4x4 and 8x8 pixels). Computer results showed that the proposed method gives an acceptable compression ratio and image quality compared with non-adaptive fitting. For 4x4-block size, there is an improvement in PSNR (25.19 dB) compared with nonlinear polynomial case (25.08 dB). In addition, CR (7.45) is better than both cases (7.11 for linear and 5.56 for nonlinear polynomial case). The results showed that the suggested method of adaptive polynomial fitting is more suitable for gray scale images (including handwriting images).

The Influence of Current & Pulse off Time on Material Removal Rate and Electrode Wear Ratio of Steel 304 in EDM

Shukry Hammed Aghdeab; Vian Nihad Najm

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1845-1856

EDM (Electric Discharge Machining)machine was used for machining of conducting cutting materials such as steel 304in dielectric solution (diesel fuel) by supplied byDC current values (10, 20, 30, 42 and 50A). Voltage of (140V) was used to cut (1) mm thickness.
The experimental results reveal that the material removal rate enhanced by increasing the current values also show that the Electrode wear ratio rises with increase in the current values. It is also concluded that the material removal rate reduces with increasing the pulse off time values and the electrode wear ratio.

Studying Strength and Stiffness Characteristics of Sand Stabilized with Cement and Lime Additives

Zeena W.S. Abbawi; Kawther.Y.H.AL-Soudany

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1857-1875

The present work investigates the strength characteristics of sand stabilized with two additives (cement and lime) each alone at different percentages ranging between 1-10%. Sand mixed with different additive contents are statically compacted in perforated tubes, 38 mm in diameter and 200mm in length, the perforated holes are 2mm in diameter along the tube. Compaction is carefully controlled by compressing the sand to the required density by two plungers at top and bottom, two ends of the samples are waxed and soaked for 7 and 28 days in water. Unconfined compression test were performed, the strength and stiffness were determined for all the samples.
Results referred to an increase in strength and stiffness of stabilized sand with increasing additives content, cement treatment improved strength significantly rather than lime and soaking time plays an important role in increasing compressive strength of sand treated with cement and lime. Also results showed that the type of failure behavior varied greatly from plastic to brittle. An empirical equation was derived for the unconfined compression strength depending on type of additive and soaking time.

Weight Sensors Based Human Walking Step Recognition System: Implementation and Statistical Evaluation

Sahar Salman Mahmood

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1876-1889

It is well known that with the growing of the humanity and all the development in technologies, there is an increasing in need for recognition systems. These systems can recognize people from distinct characteristics in which these are unique for each one individually. The researchers went to the finger print and eye recognition methods to be adopted as the dominated approaches, yet, these methods suffers from numerous health risks due to diseases transferring. Therefore, the walking step recognition method has been adopted recently. This is because each person has different walking style from others.
This paper proposed a human walking step recognition system that adopts group of weight sensors distributed amongst carpet. The reading data from sensors has been transmitted to the information center for processing. The data is transmitted through out a wired sensor network that includes sensor nodes and sink node. The latest node is used to collect the reading data from the sensor nodes. At the information center, the received data is processed using the proposed recognition algorithm. This algorithm gives two decisions; either matching with full information about the intruder or no matching. On the other hand, the proposed system has been designed and implemented using MATLAB simulator. Throughout this simulator, a database matrix is generated randomly to cover all the probability of walking step patterns available for humans. This matrix consists of three dimensions; one for users, second for sensor readings (walking patterns), and third for tries. Each user records numerous walking patterns by passing over the designed carpet several times at different modes just to cover the slightly changes in walking style in terms of modes. It is important to note, that the carpet include the sensors in between of two layers.
The simulation results show the successful performance of the proposed system with high efficiency and recognition accuracy. In addition, statistical analysis has been obtained using sampling theorem by adopting sample of 100 employees at University of Technology. Thisis done by distributing a questioner form over the employees to evaluate the acceptation of the proposed system by people in terms of health issues and ease of use. The outcome results show high ratio of accepted people in comparison with rejected.

Protect Digital Elevation Model (DTM) from Aerial Photographs by Using (ERDAS IMAGINE)

Yousif Husain Khalf AL-kinani

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1890-1900

The Digital Terrain Model (DTM) is considered a common tool in producing topographic maps, orthophotos and civil engineering projects besides other different engineering applications. As a result, many software packages were developed and used to produce (DTM ) from different sources like filed surveys, scanned topographic maps and stereo photos exposed from air or space .
This research is devoted to evaluate the most suitable and accurate in producing digital elevation model from two different sources' the first source is ground surveys for the area north of Iraq (Iraqi Iran borders ) by using Global Position System (GPS) the second source is the aerial photos. Thebasic topic is producing Digital Elevation Modal (DEM), and orthorectify images, and hownew technique and software in aerial photogrammetrycanbe useful to produce topographic maps and also, getting idea with detail about what these software need to run aerial triangulation.
The (DTM) has been produced from strip of aerial photos in the North of Iraq (Iraqi Iran borders). Also, theorthometric corrections for these photos have been done so that we can use these images to produce topographic map. The type of the used camera was (Ziess rc10_1975) and the date for these images is 1975, the scale of these photos is 1/30000, and the averageof flying height is 4500m above mean sea level.
The software we used in this research was ERDAS Imagine LPS (Lieca photogrammetric system).

Desulfurization and Kinetic Study of Diesel Fuel by Batch Adsorption on Activated Carbon

Neran K. Ibrahim

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1901-1916

The present research studied a batch adsorption desulfurization process for diesel fuel containing 580ppm sulfur, based on physical adsorption of refractory sulfur compounds on activated carbon (AC). The effects of time, temperature, diesel to AC ratio, AC particle size, mixing velocity, and initial sulfur concentration in commercial diesel fuel on the desulfurization efficiency were studied. The residual sulfur concentration in diesel fuel was decreased from 580 to 247ppm, corresponding to a desulfurization efficiency of 57%, at best conditions of 2.5 hours contact time, 50°C, 2ml diesel/gm AC, 0.8 mm AC particle size, and 1000rpm mixing velocity.Different kinetic models were applied to fit the experimental data. The results showed that the pseudo-second order model has succeeded in predicting the equilibrium sorption capacitywithcorrelation coefficient, R2=0.995. The experimental adsorption isotherms were correlated by Langmuir and Freundlich models. The results indicated that Freundlich isotherm exhibits the best fits for the adsorptive desulfurization of diesel fuel (R2= 0.989) as compared with the Langmuir model (R^2=0.947). The adsorption intensity as estimated from the Freundlich isotherm is larger than one which is indicative of physical adsorption.

Nonlinear Thermoviscoelastic Behavior of Composite Thin Plates

Raed Naeem Hwyyin

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1917-1939

The nonlinear thermoviscoelastic behavior of composite thin plate from polyester reinforced with random fiber glass was investigated. The hereditary elasticity (viscoelastic) behavior described in new mathematical model predicted from experimental data from creep and relaxation tests to predict the creep compliance and relaxation modulus equations then apply that mathematical model in numerical and analytical analysis to describe the nonlinear viscoelastic behavior of thin composite plates at different loading and temperatures. The creep specimens and composite thin plate have the same volume fraction.
A very good agreement has been found between experimental, theoretical and FEM method. It is found that the deflection increases with approximate rate (50 %) at time (15 min.) and the shear stress (xy) increases with approximate rate (58%) at time (30 min.), as a result of increasing the distributed load (q=1.934e-3 N/mm2 to q=3.4488e-3 N/mm2) at temperature (30 Co) of relative dimension (a/b=0.5) and rectangular simply support plate. The increasing temperature from (30 Co- 60 Co) increases the deflection with approximate rate (34.6%).

Effect of Ca Addition on the Microstructure and Mechanical Properties of Al-Cu-Mg Alloy

Munthir M.Alkubasy; Noor .S.Tawfeeq

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1940-1954

In this research the effect of pure (Ca) element addition in different percents of (0.3,0.6,0.9%) on the microstructure and mechanical properties of Al-Cu-Mg alloy were studied .The Alloys were produced using sand casting and heat treated using (T6) treatment which involve [solution treatment , quenching , artificial aging ], aging process were carried out at 220º C for different periods of time ranging between (5min to5hr).Also the work involves a study on the effect of (Ca) addition on both grain size as well as the resulting phases before and after heat treatment, samples were examined using optical microscope, Scanning Electron microscope ,X-Ray diffractometer and image-J software to estimate the average grain size.The results of hardness and tensile tests for (0.6% Ca) and 4hr aging show the best response as compared with the other alloys. The hardness and strength values have been changed from (78.29HV),(110.57Mpa) respectively during (30min)at 220ºC for (non-Ca) content alloy to(125.9HV),(164.2Mpa) for (0.6%C) alloy. X-Ray diffraction , results shows the basic phase that forms is Al2CuMg (Sˋˋ, Sˋ phase) which is considered as the main strengthening phase in Al alloys, and it was found that (Ca) addition leads to form (Al4Ca) and (Al2Ca) which delay the alloy response to precipitation hardening by delaying the formation of (S)phase. Also (Ca) addition in the range of (0.3- 0.6%) gives the refining effect as shown from image-J results ,While increasing Ca content up 0.9%wt has resulted in a reduction in the grains refining which leads to a decrease in hardness and tensile strength, From these results the decrease in tensile strength with increasing Ca content over 0.9% seems to be attributed to the reduction in elongation caused by the occurrence of micro porosity due to (Ca) addition.

A New Algorithm for a Steganography System

Atheer Alaa Sabri; Marwa Jaleel Mohsin

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1955-1970

Steganography is the workmanship and study of concealing mystery information to provide a safe communication between two parties.This paper,displays othersteganographic algorithms for implanting encoded secretimagein grayscale and colorimages to give abnormal state security of information for correspondence over unsecured channels.The proposed algorithms first analyze the secret image using 1level -DWT and SLT respectively. It will be then encrypted the low frequency components of the secret image only using AES method and then embedded in the insensitive mid and high sub-bands gotten from the cover image in the wake of applying 2level- DWT and SLT on it, The embedding method used in this paper is LSB, the resulting image called stego-imageform different algorithms are then compared. .By using the proposed algorithms the capacity of the hidden secret data and stego image quality are improved. The embedding image reaches to half the size of cover image at same time PSNR reach to 62 dB and MSE about 0.36. The language used for testing the algorithms is MATLAB 2013a.

Comparative Study of Some Properties of Two Groups’ Binary Polymer Blends Prepared By a Twin-Screw Extruder

Sihama I. Al-Shalchy; Kadhum M. Shabeeb; Rula F. Hasan

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1971-1985

In this paper, the preparation and compare of some mechanical and physical properties of two groups of polymer blends consisting of polyvinyl chloride with polypropylene (PP-PVC) and poly-vinyl chloride with high-density polyethylene (HDPE-PVC). Using a twin-screw extruder, three weight percentages of PP and HDPE (5, 10 and 15%) were used to prepare the polymer blends. Experimental investigation was carried out for analyzing the mechanical properties liketensile strength, flexural strength, compression, impact, and hardnessand physical properties (thermal characteristics and melt flow index) for the polymer blend samples. The results show that the polymer blend (HDPE-PVC) get higher values than polymer blend (PP-PVC) in fracture strength, young´s modulus, elongation, flexural strength, creep resistantand maximum shear stress and thermal characteristics, whereas the polymer blends (PP-PVC) get higher values in impact strength, fracture toughness, hardnessand compression and melt flow index. Besides, the increment in PP or HDPE content weak the properties of the polymer blends and the samples with (5%PP:95%PVC) and (5%HDPE:95%PVC)were the best among the other polymer blends samples.

Implementation of an Electro-Pneumatic Prototype Elevator Controlled by PLC

Jamal Abdul-Kareem; Hatem Kareem; Athraa Sabeeh

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1986-1998

The current paper presents a new simple and clear and implementation method for prototype Electro-pneumatic prototype elevator system. The controller used for the prototype was implemented in Ladder logic on a PLC. The PLC used for this work is (LSGLOFA-G7M-DR20A) series with (8) input and (12) output. This elevator system can be used for learning the structure of the elevator as well as the control strategy involved in elevator system for educational purposes. The research work can serve in learning enhancement for the undergraduate's students in the Electromechanical Department in the University of Technology

Analysis and Optimization of Resistance Spot Welding Parameter of Dissimilar Metals Mild Steel and Aluminum Using Design of Experiment Method

Sabah Khammass Hussein

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1999-1011

This research aims to study the effect of parameters of the resistance spot welding (RSW) on the shear strength of the spot weld for different metals {AA 6061-T6and AISI 1010}using (0.5 and 0.7 mm) thickness.Three values for each welding parameters (welding current, electrode force, squeeze time and welding time) are to be used. The effect of those parameters have been analyzed by Minitab program by design of experiments (DOE) in order to determine and reduce the number of specimens required to achieve the tests. The design of experiment method which used was Taguchi method
The experimental tests that had been done are shear, Microhardness and microstructure tests.It was found that the maximum shear force in welding of dissimilar metals(AA 6061-T6 with AISI 1010)is (F = 1.14 KN for t = 0.7 mm ).This value has been optimized to reach (F =1.24KN) using DOE. The minimum shear force was(F = 0.25 KN in t = 0.5 mm).
In general, increasing the welding current and sample thickness gave an increase in the shear force, but at the same time the reduction in shear force have occurred during the increasing in electrode force, squeeze time and welding time.From Microhardness tests, the maximum value of hardness is found at the center of nugget zone (NZ) and it reduces slightly until reaching constant values away from NZ.

Improving Energy Saving in Conventional Pneumatic Systems by Using Air Booster Experimentally

Jafar Mehdi Hassan; Majid Ahmed Oleiwi; Amer Abed Mansour; Walaa Mousa Hashim

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 1012-2026

Pneumatic actuators are widely used in industry and many other applications, whereas low energy efficiency has been recognized as a critical drawback compared with corresponding hydraulic and electrical actuators. The paper presents a study to improve the performance and energy efficiency of the traditional pneumatic drive with vertical load 50N, by added air booster type IPR (Input Pressure Reduce) to the.Four supply pressures used 2, 4, 6 and 8 bar, compared with the traditional control of the motion of the asymmetric cylinder in which maximum energy saving obtained at 6 bar16.7%.

Teaching Strategies Consistent with Structures of Knowledge of learning content belong to Syllabus in Architectural Departments

Nawfal Joseph Rizco

Engineering and Technology Journal, 2015, Volume 33, Issue 8, Pages 183-209

Learning Process isn’tbased on learning Content only, but it is based on thelearning content with its structures of Knowledge and the Learning Strategy. And this Process ought to put the student in its core.It is necessary that the teacher should improve his choice in selecting the learning Strategy, and also his choice in selecting the appropriate activity and tools that can achieve certain goals, and so the research interests in studying the Consistency between the nature of learning content which isdetermined by its structuralknowledge (Facts,Concepts,Principles,Generalizations,Skills, Attitudes, Values),and learning Strategies in one of the Engineering Department that combines in its learning Curriculum between Natural and Social Science which combines between two different logics (the intentional logic and the Extensional logic). This combination between these two different fields (Social & Natural Science) posit that the teacher should give a special importance to the reliable Learning Strategy which he or she depends on in the lecture room ,in order to communicate the content of syllabus to students and accomplish the well understanding in a simplest, faster ,and more efficient way. So, the research seeks to study the consistency between the learning strategies and the learning content in its structural knowledge which belongs to the Curriculum syllabus reliable in ArchitecturalDepartments and for all teaching stages. The research concludes the connection between the learning content and its Scientific Field which is more consistent with, and the connection between the learning strategy and the scientific field of learning content .Also, the research gives some recommendations includingespecially the necessity of distinction between the syllabus which belong to natural and social science and that matter reflects its effect on the type of learning strategies that consist with each field.