University of Technology-IraqEngineering and Technology Journal1681-690029320110201Some Factors Effecting on the Dielectric Strength for (PVC- Kaolin) Composites1031162710610.30684/etj.29.3.18ENJournal Article20110201This research includes the effect of kaolin additions to the polymer matrix (PVC)<br /> and study some factors affecting to dielectric strength.<br /> The kaolin powder was added as percentage by weight (1,2,3 and 4%) to PVC,<br /> and the specimens formed by hot pressing method, with different thickness (0.8-2<br /> mm). Some of the results was showed decrease in the electrical strength with kaolin<br /> additives, especially for large thickness due to presence of lattice water, which has<br /> high dielectric constant but in the same time has high dielectric loss factor, where the<br /> electrical strength decrease when dielectric loss factor increases. Thus the influence of<br /> leakage currents is evident in the large thickness as a result of the electro-thermal<br /> effects.<br /> Electrical strength was decreased when the time rate of raising voltage increases.<br /> The effect of the cycles number of breakdown for composite specimens was studded.<br /> Also the dielectric strength decreased with temperature increases.<br /> Optical microscopy images for breakdown region was shown the<br /> carbonization in the breakdown points as a result of crashing polymers chains.<br /> Also, micro cracks occurring for specimens that has large amount of kaolin and<br /> this cracks extend directly from the breakdown region.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Study of Spectroscopy and Thermodynamic Properties for Germanium Tetrafluoride GeF4 Molecular and Study of Potential Energy Curve for Bond (Ge-F)1171242710810.30684/etj.29.3.19ENJournal Article20110201In This research Complete study Spectroscopic and Thermodynamic<br /> properties for molecule GeF4 . This included calculation of potential energy<br /> curve . from this curve total energy of molecule at equilibrium distance<br /> calculated , for bond (Ge - F) the degenerated of (Ge -F ) bond was (2.99 ev)<br /> instate of that the vibration modes of GeF4 and frequency in IR spectra region<br /> because variable of dipole moment for molecule. Also we calculated<br /> Thermodynamic properties for GeF4 such as Heat of formation , Enthalpy , Heat<br /> of Capacity and Entropy Were (-290.231 kcal/mol , 4198.48kcal/mol , 19.61<br /> kcal /k/mol , 82.25 kcal /k /mol,) respectively all at room temperature and one<br /> atmosphere ( 298 k , 1 atm.) , and we calculated this properties at various<br /> temperature from ( 100 – 3000 ) K . The calculated results are in a good<br /> agreement with experimental resultsUniversity of Technology-IraqEngineering and Technology Journal1681-690029320110201Thinking Skills in Architectural Work A Study of Thinking Skill Levels at Student of Architecture1251522712010.30684/etj.29.3.20ENJournal Article20110201A skill is the learned capacity to carry out pre-determined results often with<br />the minimum outlay of time, energy, or both . Skills can often be divided into<br />domain - general and domain - specific skills . An architect should ideally be a<br />person possessing large variety of skills and capabilities like : good<br />communication, shows strong drawing able to solve problem, capable in abstract<br />thinking and seeing the wider context of things and believes in collaboration. In<br />practice, architects usually are good at technologies, project work, but in the<br />previous studies they seem a lacking of framework knowledge about thinking skills<br />and their levels in architectural education , and that what the research problem<br />concentrates on .To achieve this it is necessary to : formulate conceptual<br />framework about thinking skills which consists of three layers : first, the nature of<br />thinking (kind and its direction), second productive thinking strategies , and third<br />the necessary skills to fulfill the design process which consists of eight skills , and<br />the application focuses on four ; focusing skills, organizing skills, analyzing skills<br />and generating skills which applied on texts written by the students themselves .<br />This paper shows that the significant skill was focusing skills, where the students attending to selected piece of information and ignoring others by well defining<br />problem .University of Technology-IraqEngineering and Technology Journal1681-690029320110201Transient Thermal Stress Prediction Due To Flow of Coolant Through Hot Pipe4234332617610.30684/etj.29.3.1ENAnes F. SaadJalal M. JalilJournal Article20110201Transient thermal stresses in pipe wall due to coolant turbulent flow<br /> through pipe are investigated in this study with transient isothermal hot boundary<br /> in the external pipe radius. Three Different values of Reynolds are tested (3000,<br /> 5000 and 8000). Finite volume method was used to calculate the velocities and<br /> temperatures fields in the working fluid (air). Thermal resistance method was used<br /> to calculate the transient temperature distribution in the pipe wall and then the<br /> transient thermal stresses were calculated. Minimum thermal stress was located<br /> nearly in the mid plane of the pipe.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Three-Dimensional Flow Model for The Downstream of Kuffa Barrage4344412617710.30684/etj.29.3.2ENMajid H. HobiSaleh I. KhassafMuhannad J. M. Al-KizwiniJournal Article20110201The three-dimensional numerical computational fluid dynamics “CFD”<br />computer program "SSIIM" was used to predict the flow field downstream the<br />Kuffa Barrage. It solved the Reynolds-Averaged Navier–Stokes equations in three<br />dimensions to compute the water flow and used the finite-volume method as the<br />discretization scheme. The model was based on a three dimensional, nonorthogonal,<br />structured grid with a non-staggered variable placement. The<br />comparison between filed measurements and numerical results were considered to<br />make the correct decision in this model. The results showed that the maximum<br />velocities were inclined from the river center. The determination coefficients for<br />distribution of velocities ranged from 0.94 to 0.96.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Applicable Studies of the Slow Electrons Motion in Air with Application in the Ionosphere4424612617810.30684/etj.29.3.3ENS. S. DawoodF. G. HamudyM. I. IsmaeelI. G. FaiadhJournal Article20110201In this study, the motions of slow electrons in air and nitrogen with it's<br /> mixtures are studies by details. We solved numerically Boltzmann transport<br /> equation to calculate the parameters E, Vd<br /> and D/m have been possible to deduce<br /> expression empirical formula from which may be derived the drift velocity,<br /> collisional frequencies, electronic temperature and mean energy loss per collision.<br /> These results applied to the ionosphere allow electronic collisional frequencies to<br /> be ready found in the ionosphere below 94 km, from the pressure of the air. The<br /> collision cross-sections of the molecules of air and nitrogen when the electronics<br /> temperature is less than about 2600°K.<br /> The addition results are presented for electrons drifting through air in a steady<br /> state of motion under the action of the electric field, such as, KT, U, Q, Q0, ω,<br /> ω/P,h, hKT , and W/D for both Maxwell and Druyvesteyn distribution laws. This<br /> parameters are graphically as a functions for their variables.<br /> The results appeared excellent agreements with the experiments and<br /> theoretical data.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Edge Detection Based on Standard Deviation Value and Back Propagation Algorithm of Artificial Neural Network4624692618110.30684/etj.29.3.4ENAmmar Sabr MajedMohammed Hussien MiryAli Hussien MiryJournal Article20110201This paper presents a proposed neural network based edge detection<br /> algorithm. we have used artificial neural network system to decide about whether<br /> each pixel is edge or not. First standard deviation values are computed for mask<br /> (3*3), Then after training a neural network system to recognize structural patterns<br /> (these pattern represents edges), it decides on each pixel if its edge or not. Finally<br /> we have test the proposed method on different images. Experimental results show<br /> the ability and high performance of proposed algorithm.University of Technology-IraqEngineering and Technology Journal1681-690029320110201A Study Of Some Hydrological Aspects For Spillway Design of A Small Dam In The North of Iraq4704762618210.30684/etj.29.3.5ENSahar A. MohammadJournal Article20110201This research is to evaluation and analyzing the main aspects of spillway design<br /> for Chaq-Chaq dam in north of Iraq in Suleimaniya governorate, with help of the<br /> hydraulic, hydrologic and climate data collecting. Four different distribution models<br /> are used in order to conduct the analysis required to find the different return periods<br /> of flood, based on the expected daily rainfall depth, also the result was compared<br /> with the study of Sogreah consulting company .Analysis of data shows that the<br /> length of the spillway of Chaq-Chaq dam should be increased by about 206% to<br /> accommodate the maximum flood discharge according to Extreme Value type I<br /> distribution with return period of 1000 year.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Experimental Investigations Heat Transfer and Pressure Drop Characteristics of Flow Through Circular Tube Fitted With Drilled Cut-Conical Rings4774872618310.30684/etj.29.3.6ENAmeer A. JadoaaJournal Article20110201The heat transfer rate and pressure drop characteristics of turbulent flow of air<br /> through uniformly heated circular tube fitted with drilled cut conical rings with<br /> three space ratios (X=5.4, 6.4, and 8.4) have been studied experimentally. The flow<br /> characteristics are governed by space ratio (the ratio of the distance between drilled<br /> conical ring and the inner diameter of tube), Reynolds number, and drilled conical<br /> ring diameter to inner diameter of tube. The goal of the present work is to<br /> investigate the effect of drilling of the cut conical ring turbulators (with constant<br /> ring to tube diameter ratio) and space ratio on heat transfer, friction factor, and<br /> enhancement efficiency under ranging of Reynolds number from 5000 to 23500.In<br /> addition, correlation for Nusselt number, friction factor and performance<br /> evaluation criteria to assess the real benefits in using the drilled-conical ring<br /> turbulator of the enhanced tube are determined. The results show that the process<br /> of drilling of the conical ring inside tube gives high rates of heat transfer more than<br /> that in the conical ring without drilling.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Poisson's Ratio as a Function of Time in Composite Material of Viscoelastic Behavior by Depending on Creep Test4884982618410.30684/etj.29.3.7ENAzhar Sabah AmeedJournal Article20110201In viscoelastic behavior of composite material, such as those made of thermo-set<br /> polyester and one layer random fiber glass, the Poisson’s ratio is described in new<br /> function of time and stress. The relaxation stress is obtained experimentally to describe<br /> the non-linear viscoelastic behavior in composite material. The results show that,<br /> Poisson’s ratio increases with an approximate rate of 16% as a result of the increasing<br /> stress from 6.877 MPa to 8.239 MPa and decreases with increasing the time at constant<br /> temperature 30 Co.<br /> The investigation demonstrated that such time dependence is not a necessary<br /> consequence of the theory of viscoelasticity to describe viscoelasticity behavior.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Design and Implementation Web Site for UOT Using Mobile Devices4995122618510.30684/etj.29.3.8ENZahraa Abid AL-HuseenAimen KazimMohammad NatiqAlaa KadhimJournal Article20110201A mobile phone allows its user to make and receive telephone calls to and<br /> from the public telephone network which includes other mobiles and fixed-line phones<br /> across the world. In addition to being a telephone modern mobile phones also support<br /> many additional services, and accessories. such as SMS (or text) messages, e-mail,<br /> Web access, gaming, Bluetooth and infrared short range wireless communication,<br /> camera.<br /> The Mobile Web refers to the use of Internet-connected applications, or browser-based<br /> access to the Internet from a mobile device - such as a Smartphone or tablet PC -<br /> connected to a wireless network. In this paper, we design and build an web application<br /> on the mobile devices and access to the web services to display the university of<br /> technology website.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Effective Web Page Crawler5135302618610.30684/etj.29.3.9ENHilal Hadi SalehIsraa TahseenAliComputer Sciences Department, University of Technology/BaghdadJournal Article20110201The World Wide Web (WWW) has grown from a few thousand pages in<br /> 1993 to more than eight billion pages at present. Due to this explosion in size,<br /> web search engines are becoming increasingly important as the primary means<br /> of locating relevant information.<br /> This research aims to build a crawler that crawls the most important web<br /> pages, a crawling system has been built which consists of three main<br /> techniques. The first is Best-First Technique which is used to select the most<br /> important page. The second is Distributed Crawling Technique which based on<br /> UbiCrawler. It is used to distribute the URLs of the selected web pages to<br /> several machines. And the third is Duplicated Pages Detecting Technique by<br /> using a proposed document fingerprint algorithm.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Structural and Optical Properties of Lead Iodide Thin Films Prepared By Vacuum Evaporation Method5315432618710.30684/etj.29.3.10ENKhalid M. ThajeelModaffer A.MohammadAli M .MousaShatha Sh. JamilJournal Article20110201Structural and optical properties were studied as a function of films thickness for<br /> thermally evaporation PbI2 films. X-ray diffraction analysis confirmed that PbI2<br /> films are polycrystalline having hexagonal structure. The optical absorption data<br /> indicate an allowed direct transmission with optical energy gap varies continuously<br /> from ( 2.15eV to 2.33eV) . The energy gap shows thickness dependence, which<br /> can be explained qualitatively by a thickness dependence of grain size through the<br /> decrease of the grain boundary barrier height with grain size. The low fluctuation<br /> in energy gap indicates that the grain size is quite small, which is finding in<br /> agreement with AFM results.University of Technology-IraqEngineering and Technology Journal1681-690029320110201On Left s -Centralizers Of Jordan Ideals And Generalized Jordan Left (s ,t ) -Derivations Of Prime Rings5445532618810.30684/etj.29.3.11ENAbdulrahman H. MajeedAnwar Khaleel FarajJournal Article20110201In this paper we generalize the result of S. Ali and C. Heatinger on left s -<br /> centralizer of semiprime ring to Jordan ideal, we proved that if R is a 2-torsion free<br /> prime ring, U is a Jordan ideal of R and G is an additive mapping from R into<br /> itself satisfying the conditionG(ur + ru) = G(u)s (r) + G(r)s (u) , for all<br /> uÎU, r ÎR . Then G(ur) = G(u)s (r) , for all uÎU, r ÎR . Also, we extend the<br /> result of S. M. A. Zaidi, M. Ashraf and S. Ali on left (s ,s )-derivation of prime ring<br /> to Jordan ideal by introducing the concept of generalized Jordan left (s ,t )-<br /> derivation.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Detection of Water-Table by Using Ground Penetration Radar (GPR)5545662618910.30684/etj.29.3.12ENAhmed Fouad NashaitMundher Ali SegerJournal Article20110201Ground penetrating radar, GPR, is a high resolution geophysical method,<br /> which is based on the propagation of high frequency electromagnetic waves. The<br /> GPR method images structures in the ground that are related to changes in<br /> dielectric properties. In sediments, water content primarily causes the changes in<br /> dielectric properties. Therefore GPR can be used to estimate underground watertable.<br /> In this study a GPR system has been used successfully to produce a<br /> continuous profile of the water table on the (Said Abdullah bin Al-Hassan Shrine)<br /> as a study area, which is located in Al-Yousifyah region to the south of Baghdad.<br /> Geotechnical field test to underground water determination by the drilling method<br /> commonly used to comparing the results between geotechnical field test and GPR<br /> test. Thus, GPR has proven to be an effective detection method for underground<br /> water level, and can serve as reference for future applications.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Residual Stress effect on Fatigue Behavior of 2024- Aluminum alloy5675782619010.30684/etj.29.3.13ENRiyadh A. Al-TaieFarag Mahel MohammedAhmed N.Al-khazrajiJournal Article20110201In the present work the effect of residual stress on the fatigue behavior of<br /> 2024 Aluminum alloy was studied experimentally and numerically using<br /> finite element method with aid of ANSYS-11 software. All the test<br /> specimens treated by annealing before any process to remove the internal<br /> stresses due to cold work. Residual stresses were imparted to the fatigue tests<br /> specimens by heat treatment, pre-strain and welding. X-Ray diffraction was<br /> used to measure the residual stress.<br /> The heat treatment; done on the test specimens with different temperature of<br /> (420, 450, 480, and 510) oC. After heat treatment; alloy mechanical properties<br /> were improved. For the heat treated specimens as the temperature increased<br /> the compressive residual stress increased to (27.06, 41.43, 72.8 and 85.6)<br /> MPa. That leads to increase the endurance fatigue limit by (32.93%, 40.48%,<br /> 50.68% and 61.03%) respectively than other alloy as received. While in pre<br /> strain groups; the test specimens loaded to (265, 290, 315 and 340) MPa by a<br /> tension test machine. As the applied load series were increased the<br /> compressive residual stress increased to (16.51, 25.62, 51.54 and 62.44) MPa<br /> which improve the endurance fatigue limit by (7.68%, 16.19%, 24.98%, and<br /> 46.45%), respectively. An electrical arc and metal inert gas were used in<br /> welding series to weld the test specimens, that present a tensile residual stress<br /> of (76.93 and 72.66) MPa, which reduces the endurance fatigue limit by<br /> (23.45% and 16.08%), respectively. The numerical results present fatigue<br /> behavior, deflection and stress at any load, and show a reasonable agreement<br /> results with an experimental one.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Smith Predictor with Simple Control Scheme for Higher Order Systems5795942619110.30684/etj.29.3.14ENQussay S.TawfeeqNasir A.Al-awadCollege Engineering, University of Almustansyria/ BaghdadEkhlas H. KaramJournal Article20110201A simple control scheme with smith predictor connection is proposed in<br /> this paper for time delay higher order systems. The control scheme is<br /> simply integral (I) controller with Proportional Derivative(PD)-Sliding<br /> mode controller(SMC). The initial values for the P,I, and D parameters are<br /> taken from the reduced model of the higher order system. Additional<br /> feedback sliding mode control (FSMC) is also used to reduce the effect of<br /> uncertainty in the prediction time delay values. A number of examples are<br /> tested and compared with other control methods like robust PID controller<br /> with smith predictor and Direct synthesis method with smith predictor to<br /> illustrate the efficient performance for the proposed control scheme.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Removal of Heavy Metals Using Chemicals Precipitation5956122619210.30684/etj.29.3.15ENBalasim A. AbiDMahmood M. BrbootINajah M. Al-ShuwaikIJournal Article20110201The single component and multi-component hydroxide precipitation and<br /> adsorption were studied for different heavy metals namely Iron (III), Chromium<br /> (III), Copper (II), Lead (II), Nickel (II), and Cadmium (II) from aqueous solutions.<br /> By using the jar tester Magnesia (MgO) was used as a precipitator at different<br /> doses and compared with other chemicals like lime (CaO) and caustic soda<br /> (NaOH). The treatment involves the addition of either magnesia or lime-water<br /> suspensions (combined with cationic polyelectrolyte, CPE) in various doses, 1.0 –<br /> 5.0 g/l for the metal samples to study the effect of varying doses on the treatment<br /> efficiency. The results show that the percent removal of metal ions increases to<br /> about 99 % with increasing the MgO dose to some limits. The optimum values of<br /> MgO doses were found to be 1.5-3.0 g/l. The pH value ranges are 9.5 to 10 with<br /> MgO precipitant and pH of 11.5 to 12 with CaO precipitant. In the jar experiment<br /> the rotation speed, N, 180-200 rpm, (G of 460-480 s-1) of mixing for two minutes<br /> was the most favorable speed of rapid mixing and the slow mixing speed of 15-30<br /> rpm, G of (14-35 s-1), for twenty minutes gave the best results.At the best operating<br /> conditions of the pilot plant, the removal efficiency of metal ions was more than<br /> 97% at doses of MgO (1.0-4.0 g/l).University of Technology-IraqEngineering and Technology Journal1681-690029320110201Solutions of Dynamic Fractional Order Differential Algebraic Equations System6136242619310.30684/etj.29.3.16ENAlauldin Noori AhmedJournal Article20110201In this paper, we are presented the existence and uniqueness theorem, and two<br /> proposed methods, based on the theory of Gunwald-Letnikov fractional order<br /> derivative. In the first method, the variational approach is implemented, while in<br /> the second method, the fractional difference approach is implemented. Dynamic<br /> test example is presented to each proposed method, to demonstrate their<br /> computational algorithm.University of Technology-IraqEngineering and Technology Journal1681-690029320110201Improving a Model for Speed / Density Relationship on Arterial Roads in Baghdad City6256382619410.30684/etj.29.3.17ENAbeer Khudher JameelJournal Article20110201This paper was undertaken to investigate the relationships between speed<br /> and density on urban arterial roads of Baghdad City. This research work was based<br /> on the traffic survey data (PC volume and average speed) collected in Palestine<br /> Street in 3 sections at two directions through 12 hours within 3 weekdays. The<br /> density is computed using fundamental formula of traffic flow. Eight theoretical<br /> Speed-Density models (5 are single Regime Models and 3 are Multi-Regime<br /> models) are validated by the field data by two statistical test methods (CHISQ test<br /> and Paired T-test). The results show that no one of the theoretical models is good<br /> in fit with the real data. Then a Multi-Regime Model is improved under two ranges<br /> of density (70) at south approach and (60) at north appraoch .<br /> This model is tested using regression analysis, CHISQ test, and Paired T-test. This<br /> analysis shows that the model has good fit with the field data.