University of Technology-IraqEngineering and Technology Journal1681-6900302020121201Laboratory Study of Protecting Downstream Slope of Rockfill Weirs Using Stepped Gabions4204476636110.30684/etj.30.20.15ENGhania Aed Al-Majeed HayawiBahzad Mohammad Ali NooriJournal Article20121201In the present investigation, the stability of rockfill weirs protected by gabions and subjected to overtopping flow rates under the effect of high flow rates have been studied experimentally. Five weir models with different downstream slopes [1V:2.5H,1V:3H,1V:4H,1V:5H,1V:7.5H]were constructed and tested. Fifty eight experiments were conducted for five cases of stepped gabions laying on the downstream slope[ laying gabions with one layer and no connections (M-1),laying gabions with lateral connections (M-H),laying gabions with longitudinal connections (M-V), laying gabions with two layers(M-2),and laying gabions with three layers(M-3)] using three gravel diameters (11.11,15.9 and 22.25)mm.From<br /> the data analysis, a set of equations were obtained for the estimation of failure unit discharge in terms of equivalent gravel diameter, relative submerged intensity of gabions, gabions layer solidity, and tangent of internal friction angle of gabions, for each case of gabions laying. A simple method was presented for the design of rockfill weirs protected by stepped gabions in terms of maximum failure discharge<br /> with the help of design charts obtained from the present study.<br /> A mathematical model depending on the characteristics of the physical<br /> model was derived for each slope giving failure unit discharge values that agree quite well with the experimental values. Comparing results of the present study with those of other investigations shows that rockfill weirs protected by gabions stand much higher failure unit<br /> discharge than earth weirs protected by gabions.https://etj.uotechnology.edu.iq/article_66361_f306efe0e4f993842c3fad8ddc168d47.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Finding the Weight Loss Rate of Metallic Surfaces Exposed To Corrosion Presence of Vibration (Corrosion - Vibration)4484626620110.30684/etj.30.20.14ENMouhmad Abdultef AhmedJournal Article20121201In this research the structural steel type (A36) samples were prepared by<br /> traditional preparation operations , chemical composition of samples was analyzed<br /> , hardness tested, then testing corrosion was achieved for two major cases, a<br /> general corrosion case when the corrosive medium (sea water) is static for five<br /> days period ,and the second case is the corrosion with presence of mechanical<br /> vibration, which included two branch cases , first case; corrosion of vibrated<br /> samples with the vibrated corrosive medium, and the second case when the<br /> samples are fixed and corrosive medium is vibratory , a total test period is five<br /> hours for each case ,then found weight loss and the corrosion rate of all cases of<br /> corrosion mentioned by a traditional weight loss method , as well as study the<br /> microstructures before and after the corrosion cases and to find an experimental<br /> mathematical formula that illustrate the relationships between corrosion and<br /> corrosion with presence of vibration, note that the used device to study the<br /> mechanical vibration effect was locally designed and manufactured, according to<br /> the modified American Standard (ASTM G32).Observed that the weight loss and<br /> corrosion rate reached the highest value in the second case of corrosion with<br /> presence of mechanical vibration (fixed samples and corrosive medium is<br /> vibratory), followed by the first case of corrosion with presence of mechanical<br /> vibration (vibrated samples with the vibrated corrosive medium), and less the value<br /> of the corrosion rate and weight loss is the state of general corrosion (corrosion in<br /> the static medium). It was noted that the microstructure of the structural steel<br /> became uniformly corroded after general corrosion case (in static corrosive<br /> medium) and corrosion regions were spread or scattered over all parts of the<br /> sample surface on a regular basis, while the microstructure in the two cases of<br /> corrosion with presence of mechanical vibration containing irregular corrosion<br /> cavitations and scattered randomly on the surface, and more deeply especially the<br /> second case (fixed samples and corrosive medium is vibratory). Illustrated from the<br /> results and carves there was relationship between mentioned corrosion cases, it was<br /> an experimental mathematical formula:<br /> Acc.C.R.= Vib-C.R2 – ( Vib-C.R1 +Static C.R.)https://etj.uotechnology.edu.iq/article_66201_dfc9bdfdf3446b76801c506b454bc377.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Experimental and Theoretical Study of Heat Liberation of Reciprocating Air Compressor347434906617610.30684/etj.30.20.1ENHaqi Ismael QattaJournal Article20121201In this paper an approach is presented to estimate the temperature , heat<br /> transfer rate and heat liberation of a reciprocating air compressor . The<br /> experimental work was performed by using double cylinder compressor<br /> working by three stages to reach the final pressure. In the experimental work,<br /> recording the final pressure for three stages ,and recording the temperature<br /> at suction valve, delivery valve and the cylinder wall . In the theoretical part<br /> a computer program used to solve model of single zone and depending on<br /> step by step , and calculating the amount of heat liberation by analysis<br /> pressure diagram ,the program depend upon the first law of thermodynamic<br /> and gases .<br /> The result that shown the maximum temperature inside compression<br /> space from TDC , also the rate of heat liberation increased with increase of<br /> compressor speed.https://etj.uotechnology.edu.iq/article_66176_a0d6914852c212b987163abeb996dcc0.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Theoretical Prediction of Cavitation in Radial Inflow Turbines at Design and off-Design Conditions349135056617710.30684/etj.30.20.2ENJafar M. HassanMohammed I. MohsinJournal Article20121201A theoretical method for the prediction of cavitation in hydraulic radial turbines is<br /> developed in this work. The method combines a steady, quasi-three dimensional<br /> analyses which are based on the streamline curvature technique with an approach for<br /> the prediction of cavitation based on the definition of "available" and "required"<br /> cavitation coefficients. A radial inflow turbine is selected as a test case to investigate<br /> the capability of the present method as a cavitation prediction tool at design and offdesign<br /> conditions. The effects of various operating conditions on the cavitation<br /> inception are examined at constant values of total head and turbine suction head. It has<br /> been found that cavitation is formed near the outlet when the turbine operated at the<br /> design speed. While at off-design speeds and flow rates, cavitation covers longer<br /> distances along suction and pressure surfaces.https://etj.uotechnology.edu.iq/article_66177_040b47ad7336f1327415e666ceae1002.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Numerical and Experimental Investigation of Plate Buckling under In-plane Loading350635236617810.30684/etj.30.20.3ENNaseer Hamed FarhoodJournal Article20121201The objective of this work is to predict the plate elastic buckling includes<br /> critical buckling load and corresponding buckling mode for stiffened and unstiffened<br /> plate under in-plane loading. The numerical study has been achieved by<br /> employing the FEM (ANSYS package ver.11) using a shell element of eight nodes<br /> with five DOF at each node as a discretization element such that the equation of<br /> elastic stability with isotropic material properties has been taken into consideration<br /> studies.<br /> The study of aluminum alloy 6063-O plates subjected to in-plane loading showing<br /> the effect of stiffened plates, stepped thickness, and changing of applied loading. It<br /> has been found that buckling strength increases when plate width (b) increase for<br /> stiffened and unstiffened plate, also critical buckling load has high values for<br /> biaxial load than uniaxial for plates with the same specification. Also, an<br /> experimental test has been performed on different cases which exhibit a good<br /> verification of results.https://etj.uotechnology.edu.iq/article_66178_9a8876d89a88688ddefe93e8cec1d1ba.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201The Use of Okra as a Coagulant and Coagulant Aids in the Removal of Heavy Metals of Solid Waste Leachates352435356617910.30684/etj.30.20.4ENAdnan A. Al-SamawiAko R. HamaJournal Article20121201Coagulation-Flocculation processes play an important role in the treatment of water<br />and wastewater. Aluminum sulfate (alum) and polyelectrolyte (polymer) are the<br />common chemical coagulants which are used in this process. The produced leachate in<br />waste disposal places is considered to be one of the highly contaminated resources<br />from the physical, chemical, and biological point of view.<br />In Sulaimaniah, Tanjaro was found to be one of those solid waste landfill areas.<br />Okra is used for the treatment of raw leachate samples that obtained directly from<br />Sulaimaniah – Iraq solid waste sanitary landfill area. Fresh solid waste samples of the<br />leachates were taken and tested for their heavy metals concentrations contents. It was<br />found that the leachate contains a high amount of heavy metals of cadmium,<br />chromium, copper, nickel, and zinc. By using conventional coagulants of alum,<br />polymer and natural indigenous okra (as a primary coagulant or in combination with<br />the other two primary coagulants) and by the jar testing, the best concentrations and pH<br />values of the coagulants were determined. Analyzing the results, it was found that the<br />optimal pH values were 6.65, 9.00 and 7.00 for alum, polymer and okra, respectively.<br />In addition, the best dose of alum was1400 mg/L in which a removal of heavy metals<br />yielded 45-80 %, while the best dose of polymer was 500 mg/L in which a removal of<br />70-95% was achieved. For okra, the best dose was 500 mg/L in which a removal of<br />heavy metals yielded 20-100%. It was found that okra has an efficient coagulation<br />power with respect to alum and polymer in removing heavy metals elements in solid<br />waste leachates.https://etj.uotechnology.edu.iq/article_66179_d3e8dda1cf6e67d864dd0e40eb7ca848.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Experimental Studies On Shear Connection Between Steel and Steel Fibered Concrete Using Studs353635526618010.30684/etj.30.20.5ENKhudhayer Najim. Abd-AllahJournal Article20121201This paper aims mainly to study the effects of using steel fiber in reinforced<br /> concrete parts of composite structural elements, which consist of two main parts, the<br /> steel and concrete sections. Then to explain the effects of using the hooked ended steel<br /> fibers on the load-slip relationship between concrete and steel parts of composite<br /> structural elements.<br /> The standard push-out test is a convenient and the only available method to define<br /> this load-slip relation. There are five series of tests made on push – out test specimens<br /> prepared for this purpose. These tests are containing various percentages of steel<br /> fibers ( 0.0%, 0.5%, 1.0%, 1.5% and 2.0% ) by volume of concrete. The hooked ended<br /> steel fiber with aspect ratio 100 were used in reinforced concrete parts of composite<br /> structural elements, which consist of two main parts (the steel section and the concrete<br /> section).<br /> From the obtained results, an empirical non-linear equation was developed, to<br /> calculate the shear stiffness for connectors at any amount of slip. This will give<br /> information on the ultimate shear capacity of the shear connector, which were used in<br /> the composite structures and the corresponding load-slip relationship.https://etj.uotechnology.edu.iq/article_66180_181e22512fb22caded5bf7c8759b4137.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Text Hiding Using Artificial Neural Networks355335646618110.30684/etj.30.20.6ENHaider Tarish HaiderFaiq Sabar BajiAhmad Saeed MohammadJournal Article20121201The growth of information technology and data transfer led to increase the data<br /> attacks, so that information security becomes an important issue to keep the data<br /> saved during information exchanges in computer networks. Steganography<br /> techniques used to protect the information from being detected. The art of<br /> steganography will hide secret information into cover data, which will be sending<br /> without any change so the attack does not recognize any change into cover image.<br /> This paper use the Steganography and artificial neural networks to presents an<br /> information hiding procedure for hiding text in cover image, the secret text will be<br /> converted to binary code, also the cover image will be converted to the binary data<br /> in form of vectors. The supervised learning of neural networks will use binary<br /> patterns of hidden text as set of input values, and the corresponding cover image<br /> data as target that used as teacher signal to neural network. The generated weights<br /> from neural network and the coordinate of data block of cover image have been<br /> saved and then used to extract hidden text data.https://etj.uotechnology.edu.iq/article_66181_5a8f5091bac9a6957d48fd2b053722ca.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Optical Properties of Tin Oxide Nanostructure Thin Films Prepared by Simple and Classical Method356535726618210.30684/etj.30.20.7ENRana Osamah MahdiJournal Article20121201In the present work, preparation of transparent conductive SnO2 thin films by<br /> classical-oxidation technique of thermal evaporated tin metal films, on glass substrates<br /> was carried out. The optical properties showed high transmission at visible and NIR<br /> regions. The energy band gap was found to be (3.82eV). The structure properties<br /> showed that the tin oxide peak appears at (2q =30.24) and (2ϴ=63.39°) . The atomic<br /> force microscopy (AFM) results showed a nano-structured for the thin film with<br /> particle size ranging (15-140)nm and its root mean square (RMS) value was found to<br /> be (5.72 nm ).https://etj.uotechnology.edu.iq/article_66182_c6005f22f7d82f1536e3e369bfcb127b.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Study the Effect of Volume Fraction of Mica With Different Particle Size on the Mechanical and Electrical Properties for Unsaturated Polyester Composites357335806618310.30684/etj.30.20.8ENRafah A.NasifJournal Article20121201This study was carried out to investigate the effect of adding mica (5, 10, 15, 20, 25<br /> % vf) with variable particle size (35, 57, 70μm) on the mechanical and electrical<br /> properties of the unsaturated polyester composites. Some mechanical tests were carried<br /> out like (impact strength, flexural strength) and dielectric strength. Flexural strength<br /> and dielectric strength were found to increase with filler concentrations whereas impact<br /> strength was found to decrease at higher concentrations for all particle size.https://etj.uotechnology.edu.iq/article_66183_e40fbc408f1baa657ad371f0a38bd084.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Influence of Shape Design of MEMS (Micro-Cantilever Based Sensor) on High-Sensitivity358135956618410.30684/etj.30.20.9ENIbtissam Mahdi ShihabJournal Article20121201In this paper, a novel analysis was carried out on the biosensor microcantilevers<br /> in order to increase the sensitivity of a micro- cantilever based<br /> biosensor piezoresistive. Holes were made and compared with the basic<br /> rectangular (R), triangular (T), and step(S) profile cantilever. Effect of changing<br /> the micro-cantilevers profile and its cross-section shape was investigated. A finite<br /> element ANSYS was used to analyze these models. The micro-cantilevers are<br /> made of silicon with elastic modulus 130Gpa and poisson’s ratio 0.28. Several<br /> cases were studied by making one, two and three holes in each biosensor<br /> piezoresistive micro-cantilevers (rectangular (R), triangular (T), and step(S) profile<br /> cantilever). Results showed that triangular micro-cantilever with two holes (T22)<br /> has the better sensitivity, also showed T12 respectively 61.7% and 65% higher<br /> sensitivity than R12, S12.https://etj.uotechnology.edu.iq/article_66184_878addb7f51afd6ec012520cad0ff45a.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Comparative Study of Cellular Immune Response in Cutaneous Blastomycosis359636026618510.30684/etj.30.20.10ENHaider FaisalHiba T. HussainAzhar A. F. Al-attrraqhchiJournal Article20121201Background: The immune response against Blastomyces dermatiditis is less<br /> clear than that of Histoplasma spp. or Coccidioides spp. This study was done to<br /> evaluate the cellular immune host response in patients with ulcerative and<br /> verrucous skin lesions.<br /> Methods: This study was conducted on 50 patient attended Al-Kadhymiah<br /> Teaching Hospital/Dermatology Dep. in Baghdad (2009-2010). After processing of<br /> skin samples, all cases were studied for various lymphocyte subtypes by using<br /> direct dual immunofluorescence staining method. Independent sample t-test was<br /> used to make a comparison between groups and p-value significant.<br /> Results: Histopathological examination showed 4 biopsies of skin lesions were<br /> Blastomyces dermatitidis positive and 46 biopsies were negative, two cases were<br /> ulcerative and two were verrocous . According to this classification, the total cell<br /> counts, CD3+ cells was found statistically different (p=0.034). Plasma cell (CD19),<br /> T-helper (CD4) and T-cytotoxic (CD8) also were significant when p values were<br /> (p=0.046), (p=0.020) and (p=0.018) respectively. According to the type of lesion<br /> whether it is ulcerative or verrocous, CD3+, CD4+, CD8+ and CD19+ counts for<br /> each type were significant when, P value were (p≤0.001, p=0.003, p=0.026 and<br /> 0.050) respectively. However, there were no significant difference was seen for<br /> these cells (p>0.05) among negative lesions.https://etj.uotechnology.edu.iq/article_66185_dc8c5c15f0860c645d157b857754ee4d.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Extractions of Tin Metal from Electronic Circuit Scrap by Wet Techniques360336156618610.30684/etj.30.20.11ENMohammed A. AbbasJournal Article20121201According to the larger accumulation of electronic equipment, then new<br /> environmental techniques (wet extraction process) are studied to treat these<br /> scrap and produced a utilized metal such as tin metals that used in different<br /> industrial processes.<br /> Different experimental are carried out in this studied in order to optimize the<br /> production of Tin metal from scrap circuits (stannous chloride) such as<br /> temperature of reaction (30, 35, 45, 55, 60 c°) concentration of scrap<br /> introduced (5.0, 7.0, 10.0, 13.0, 15% wt.) and residence time through smelting<br /> step as (2.0, 2.5, 3.5, 4.5, 5.0 hrs) respectively.<br /> A characterization and monitoring for production metals occurred by the use of<br /> x-ray scanning electron microscope to scan the internal structure of Tin metal,<br /> also an atomic absorption to determine the concentrations of Tin agglomerates.<br /> The results show that; optimum conditions that produced high percent of<br /> Tin metal from stannous chloride are (53°c temperature of residence, 8.5 wt%<br /> concentration of and 4.7 hrs residence time for reduction step at 2°c/min<br /> rating ratio). Afterward for smelting stage are (388°c curing temperature and 5<br /> hrs residence time).<br /> Also the characteristic results proved that; agglomerate of Tin metal<br /> products appeared at these optimum conditions at x-ray and atomic absorption<br /> as 0.25 wt. % for standard blank metal as Cu and clear agglomerate of Tin<br /> metal in the electron microscope.https://etj.uotechnology.edu.iq/article_66186_58611dac7ad96db20472e85e91bd9966.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Mathematical Modeling of Hybrid Cooling Tower for Steam Power Plant361636366619710.30684/etj.30.20.12ENHashim A.HussainJournal Article20121201An economical and environmental requirements of hybrid cooling tower in<br /> steam power plant are represented by decreasing of outlet water temperature,<br /> reducing of water and energy consumption, and working without mist formation.<br /> The present work is devoted to study and determine the best contact method of dry<br /> and wet tower to build hybrid cooling tower.A three suggested models differs in<br /> contacting method of air and water are studied. Analysis of these models are<br /> dependent on the basic principles of thermodynamics ,mass and heat transfer with<br /> considering of initial and boundary conditions. The best model must be giving<br /> accepted values in economical and environmental requirements. A Computer<br /> program by Matlab is used for solving the governing equations and determining the<br /> suitable mathematical model. The results are indicated that the third model (air in<br /> series and water in parallel) is the best in contacting method which satisfied the<br /> economic and environment requirements .The results are recorded and represented<br /> by graphs.https://etj.uotechnology.edu.iq/article_66197_90e162268aa941ca6752f70059fe440f.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-6900302020121201Study of the Wind-Induced Dynamic Response for a Parabolic- Trough Solar Collector363736526619910.30684/etj.30.20.13ENMauwafak Ali TawfikBahaa Ibrahim KazemHaider Hussein HamadJournal Article20121201In this paper, the dynamic response of parabolic-trough due to wind loading was<br /> conducted in different flow field environment and configurations experimentally<br /> and numerically. First, Experimental modal analysis (EMA) was performed to<br /> evaluate the vibrational characteristics for prototype of parabolic trough that<br /> manufactured for this purpose. Direct pressure sensors array were used to measure<br /> the pressure values over the parabolic trough model surface due to wind load at<br /> different operational attitudes. Then, the dynamic response (displacement) of the<br /> parabolic-trough due to measured wind loads (pressure) was measured<br /> experimentally and numerically. The numerical solution for dynamic response was<br /> performed using the finite element approach. The response of the parabolic-trough<br /> to wind loads was evaluated for different wind velocities and different angles of<br /> attack. A comparison between these results was made to verify the effect of the<br /> angles of attack and wind velocity on the dynamic response. The results showed<br /> that the suggested approach gave good indication for evaluating the wind load<br /> effect on the dynamic response of parabolic trough the solar collector.https://etj.uotechnology.edu.iq/article_66199_444190d27cebe056945da84f82a2303a.pdf