Effect of Silicon cavbide addition on properties of compacted Ni- caproduced by powder technology
text
article
2011
eng
This research aimed to product Cu-Al alloys by powder metallurgy method because of it is commercial and technological important. Copper and aluminum powders were tacking then there powders mixed and blended together and classified to four parts, Silicon carbide powder added to three parts and the last remain as its then these powders mixed and then compacted in isostatic cold pressure at 7ton, then this compact samples were sintered in furnace under argon gas at 830°C for one hour, latest these samples grinded and polished to microstructure, density, porosity, microhardness and X-ray diffraction tests.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
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v.
11
no.
2011
497
507
https://etj.uotechnology.edu.iq/article_32050_1a4ef722f790a7695862db902ef00ad1.pdf
dx.doi.org/10.30684/etj.29.11.20
Using Hamming Network to Decoding Binary Cyclic Code
Hind
Abd Al-Razzaq
author
text
article
2011
eng
This work, efforts are concentrated on solving the problem of decoding binary cyclic code, using hamming neural network. Therefore, this work shows the ability of hamming network in solving one of the important problems in coding theory. It presents the results of applying hamming network as a decoding algorithm for cyclic code. The results prove the relative efficiency of hamming network in decoding large linear cyclic codes compared with other decoding algorithms.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2093
2101
https://etj.uotechnology.edu.iq/article_31939_f374dca66363b72220bad4f7505b84e6.pdf
dx.doi.org/10.30684/etj.29.11.1
Finite Element Analysis of Deformation Behavior of Wire Cold Flat Rolling
Abdul
Kareem Flaih Hassan
author
text
article
2011
eng
Flat rolling of wire is an industrial process used to manufacture electrical flat wire, medical catheters, springs and piston segments, among other products. This paper presents a 3D finite element analysis of wire flat rolling. The variations of rolling force due to roll speed changes, Effect of reduction in height on width of contact Area, and Lateral spread of wire has been discussed. It is found that a negligible increase in flow stress and rolling force does occur due to increase in the strain rate at room temperature. Besides, the results showed that the behavior of rolling force variation versus roll speed depends on the rolling reductions. A theoretical relationship has been developed to relate the reduction in height of wire to the width of contact area between the rolls and wire. This relationship depicts that the width of contact area is proportional to square root of reduction in height of wire. Finally the finite element can give a reasonable estimation of the deformation behavior in wire flat rolling, since the theoretical predictions are reasonable agreement with the experimental measurements of other authors.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2102
2113
https://etj.uotechnology.edu.iq/article_31940_8153f833dd68760d70e47efb8d872482.pdf
dx.doi.org/10.30684/etj.29.11.2
A Study of Some Mechanical, Thermal and Physical Properties of Polymer Blend with Iraqi Kaolin Filler
Najat
J. Saleh
author
Samir
Nassaf Mustafa
author
text
article
2011
eng
In the present work, polymer blends were fabricated by mixing two polymers of polypropylene and poly (methyl methacrylate) mixed in different weight percentage and different particle size of Iraqi kaolin. The study of some mechanical, physical and thermal conductivity properties was carried out on all composites. The mechanical tests included (impact, hardness, modulus of elasticity, yield strength, elongation, stress at break and compression), Lee's disc method was used to calculate the coefficient of the thermal conductivity of specimens before and after reinforcement with kaolin powder. The physical properties test included absorption tests, as well as X-ray measurement. The results have shown that after the reinforcement with different weight percent of kaolin powder, most mechanical properties such as hardness , modulus of elasticity and compression increase while impact and elongation decrease with increasing in weight percentage and a decreasing in particle size. The results have shown also that the coefficient of thermal conductivity decreases with increase weight percentage the water gain is decreased with the increase in weight percent and decrease in particle size of the filler. X-ray diffraction pattern of filled samples indicates that addition of kaolin adversely affects the crystallization of PP/PMMA blend.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2114
2131
https://etj.uotechnology.edu.iq/article_31995_efbcfdd1213644a9b599b5ee2ef9aec0.pdf
dx.doi.org/10.30684/etj.29.11.3
Proposed Hybrid Approach of Stream Cipher base on Selector of Encryption operation and Key Symmetric translate
Alaa
Kadim Farhan
author
text
article
2011
eng
A stream cipher is a method of encrypting text (to produce cipher text) in which a cryptographic key and algorithm are applied to each binary digit in a data stream, one bit at a time. This method is not much used in modern cryptography. The main alternative method is the block cipher in which a key and algorithm are applied to blocks of data rather than individual bits in a stream. One of the weaknesses in the stream cipher is to analyze the text through the use of encryption algorithms standard in encryption operations. In this paper description a hybrid structure of encryption algorithm for stream cipher, this algorithm depends on a specific elements for the selection of encryption process (logical operation (XOR, AND) between the secret key and the plain text through encryption, decryption process. the specific intelligence elements choose from key. The secret key generated from random generator will be encrypted by RSA algorithm and sends with the encrypted text inside the packet
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2132
2142
https://etj.uotechnology.edu.iq/article_31998_a830f874314d2ab59e8eca83ed1e566e.pdf
dx.doi.org/10.30684/etj.29.11.4
Effect of Non-Linear Load Harmonics on Single phase Transformer Losses and Design Active Filter
Zainab
Nadhem Abbas Al-Mousaoy
author
text
article
2011
eng
As a result of the negative effects unshaped on some of the components in power systems such as the transformers, a great concern was shown to treatment this phenomenon so we rise in this search by designing a suitable active filter with two strategies for harmonic repression. To analysis and treatment this case, using a singlephase transformer with full-bridge rectifier, and a resistant load to generate some of total harmonic current and voltage distortions (THDi and THDv). Finally, simulation results with psim software show that the designed active filter with two strategies is very effective in harmonic elimination and power factor correction of the single phase transformer.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2143
2155
https://etj.uotechnology.edu.iq/article_32011_240d970e97617fc220821fe0e3831cf6.pdf
dx.doi.org/10.30684/etj.29.11.5
Geometrically Nonlinear Free Vibration Analysis of Cylindrical Shells Using high Order Shear Deformation Theory-A Finite Element Approach
Nabil
Hassan Hadi
author
Kayser
Aziz Ameen
author
text
article
2011
eng
A nonlinear finite element model for geometrically large amplitude free vibration analysis of laminated composite shallow cylindrical shell panel is presented using high order shear deformation theory (HSDT). The nonlinearity is introduced in the Green – Lagrange sense. The effects of different orthotropic ratios, thickness ratio, curvature ratio and boundary condition are study also frequency ratio (nonlinear frequency to linear frequency) of cylindrical shell are determined as function of shell amplitude ratio.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2156
2174
https://etj.uotechnology.edu.iq/article_32013_c3d4b9fc23b422574d95786f6a2d7168.pdf
dx.doi.org/10.30684/etj.29.11.6
Nonlinear Finite Element Analysis of RPC Beams Failing in Shear
Kaiss
F. Sarsam
author
Ihsan
A.S. Al-Shaarbaf
author
Maha
M. S. Ridha
author
text
article
2011
eng
Reactive powder concrete (RPC) is a new type of ultra-high strength and high ductility concrete first developed in the 1990's in France. It is recognized as a revolutionary material that provides a combination of ductility, durability, and high strength. In this research work the nonlinear f ini t e element investigation on the behavior of RPC beams is presented. This investigation is carried out in order to get a better understanding of their behavior throughout the entire loading history. Also, a numerical parametric study was carried out on the RPC beams to investigate the influence of fibrous concrete compressive strength ( ) cf f ¢ , tensile reinforcement ratio ( ) w r , fiber content ( Vf ) and shear span to effective depth ratio (a/d) on the shear behavior and ultimate load capacity of these beams. The three- dimensional 20-node brick elements are used to model the concrete, while the reinforcing bars are modeled as axial members embedded within the concrete brick elements. The compressive behavior of concrete is simulated by an elastic-plastic work-hardening model followed by a perfectly plastic response, which terminated at the onset of crushing. In tension, a fixed smeared crack model has been used.
Engineering and Technology Journal
University of Technology-Iraq
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v.
11
no.
2011
2175
2188
https://etj.uotechnology.edu.iq/article_32016_fd5d3ef9daec25c136285b02f8e43804.pdf
dx.doi.org/10.30684/etj.29.11.7
Dynamic Analysis of Foundations on Saturated Clay Using an Energy Absorbing Layer
Saad
F. A. Al-Wakel
author
Mohammed
Y. Fattah
author
Hussein
H. Karim
author
text
article
2011
eng
In this study, a method to model the semi-infinite extension (unbounded domain) of the saturated soil is developed. In this method, the unbounded domain is replaced by an absorbing layer of finite thickness with properties that appreciably reduce the wave reflection into bounded domain. In this layer, the soil is represented by the same properties as in the soil close to the foundation (bounded domain) and a model of frequency-dependent damping is implemented. A three-dimensional dynamic analysis of rectangular footing on a saturated soil is carried out. The foundation is subjected to four cycles of harmonic force. The coupled dynamic equations with u-p formulation based on the dynamic consolidation theory are used to simulate the soil skeleton and pore fluid responses. The solid particles of the soil are represented by linear elastic behavior. It was found that a decay in wave can be noticed when the unbounded domain of the saturated soil is represented by the energy absorbing layer. In addition, the maximum displacement of the foundation will be decreased due to using the energy absorbing layer in comparison with the elementary boundaries. The excess pore water pressure that developed during the dynamic loading will be dissipated with time in a fast rate due to using the energy absorbing layer.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2189
2201
https://etj.uotechnology.edu.iq/article_32018_ee1720a841c4563261c205e72d74158b.pdf
dx.doi.org/10.30684/etj.29.11.8
Proposed Algorithm for Extracting Association Rule Depend on Closed Frequent Itemset (EACFI)
Emad
k. Jbbar
author
Yaser
Munther
author
text
article
2011
eng
Association rules are important one of data mining activities. All algorithms of association rule mining consist of finding frequency of itemsets, which satisfy a minimum support threshold, and then compute confidence percentage for each k-itemsets to construct strong association rules’. Some of these association rules are not important because the extracted knowledge from their is found in other. Hence we proposed algorithm to construct only important association rules by depend on closed frequent itemset. An itemset is closed if one of its immediate supersets has the same support as the itemset. Finding these closed frequent itemsets can be of a great help to purge a lot of itemsets that are not needed to find association rules. So that aid to reduce execution time and work space of algorithm and end the algorithm at any level of k-itemset, without construct all K-itemset.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2202
2209
https://etj.uotechnology.edu.iq/article_32021_5bef758636dd3a678ab6afef57e421e7.pdf
dx.doi.org/10.30684/etj.29.11.9
Reducing of Flammability for Polymeric Composite Material by Using Flame Retardants Coating
Ali
Ibrhim Al-Mosawi
author
text
article
2011
eng
The low thermal resistance of polymeric materials to high temperatures consideredthe main limitation to used these materials in such applications required high thermalresistance ,so ,the present research aimed to study the possibility to increasing flameretardancy of advanced polymeric composite materials reinforced by fibers bycoating by a flame retardant layer represent antimony tetroxide (Sb2O4) as a coatinglayer (4mm) thickness to react and prevent spread of flame on surface of compositematerial consist of araldite resin(AY103) reinforced by woven roving carbon - Kevlarfibers (0°-45°) and exposed this coating layer to direct flame generated fromoxyacetylene flame with different exposure distances (10mm,15mm,20mm) andstudy the range of resistance of flame retardant material layer to the flames andthermal resistance and flame retardancy after coating by antimony tetroxide as wellas rising flame resistance increased exposure distances to flame .
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2210
2215
https://etj.uotechnology.edu.iq/article_32022_25462a41914143489fd2961b1378be92.pdf
dx.doi.org/10.30684/etj.29.11.10
An Investigation of Natural Convection Heat Transfer in a Square Enclosure Filled with Nanofluid
Ayad
M. Salman
author
text
article
2011
eng
In this research, numerical solution of natural convection heat transfer of nanofluids in two-dimensional square enclosures is obtained for different values of Rayleigh numbers and volume fraction of nanofluids. Numerical simulation has then been undertaken for the mixture of Cu-water as nanofluid. The stream–vorticity form of the Navier–Stokes equations and energy equation are used in this study. The present model is utilized to obtain results in the range of Rayleigh number 103–105 and volume fractions of nanofluids (0.025-0.1). The enclosure which represent twodimensional square enclosure with heated left side wall, while the right side was cold, the top and bottom walls were adiabatic. The governing equations are solved with finite-difference technique by central difference scheme. A computer program in (FORTRAN 90) was used to carry out the numerical solution. The results are a remarkable increase in the average Nusselt number with an increase in the volume fraction. An increase in the Rayleigh number results an increase in the average Nusselt number for a certain nanoparticle. In order to validate the numerical model, the results of two previous works for square enclosure filled by water based Al2O3 nano-particles as nanofluids. The first work was variation of average Nusselt number and volume fraction for Ra number Ra=103. There are excellent agreement in results and the maximum difference between theses results reach 4.2%. A relation between average Nusselt number and Ra number also compared for other previous work. There are agreement in results and found the maximum difference between results reach to 6.5% approximately at Ra=105 which validate the present computational model.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2216
2233
https://etj.uotechnology.edu.iq/article_32025_3e58d24699f7b982302c1e369b74bfd1.pdf
dx.doi.org/10.30684/etj.29.11.11
Development of an Adaptive File Transfer Protocol (AFTP )
Alaa
Noori Mazher
author
Alyaa
Hussain Ali
author
Taif
Sami Hassan
author
text
article
2011
eng
File is one of the main storing units of information. There is a great need to transfer file through computer network especially the internet. The model that is used in Internet is the TCP-IP. The TCP-IP model consists of four layers. The lowest layer is the host network layer, the second layer is the internet layer (IP handling); while the third layer is transport layer which contains TCP and UDP. The last layer is the application layer. This paper is concerned on the User Datagram Protocol (UDP). The UDP is mainly used to transfer messages. It is asynchronous, connectionless and unreliable protocol. The UDP is not suited for transferring files because of the error or loose that could prevent us from reconstruct the original file. In order to overcome this problem new field and configuration is applied in the application layer for guarantee file sending and receiving. This field is the Cyclic Redundant Check (CRC) which is computed for each block of data and all these checks were sent over another port. At the end of receiving data the receiver checks the check matrix in order to determine the error and requesting that block from the sender. The proposed protocol is implemented using the Winsock and Visual Basic programming language
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2234
2243
https://etj.uotechnology.edu.iq/article_32026_1c777db53bd4fbbc99de66049567cc90.pdf
dx.doi.org/10.30684/etj.29.11.12
Development of Algorithms to Represent Intermediate Layers for Machining Sculptured Surfaces
Tahseen
A. Jawad
author
Tahseen
F. Abbas
author
text
article
2011
eng
The objective aim of this research is to develop an algorithm for design and manufacture sculptured surfaces that are common in a wide variety of products such as dies, automobile, and aircrafts components. In the design stage Bezier technique has been used to represent the desire surface. In rough-machining stage, the number of intermediate layers depend on the geometry of the desired surface and on the maximum allowable depth of cut, an algorithm has been proposed to represent these layers, whereas another efficient algorithm has been proposed to represent the semifinished layer depends on the tangents and normal vectors along all the points of the desired surface to create the offset surface. The desired surface generated points using Bezier technique are used as cutter location points for the finish machining tool path. Flat end mill (φ 12mm) has been used for the intermediate stages machining (roughing), while (φ 12mm) ball end mill have been used for both semi-finish and finish machining. The developed algorithm have been tested by several designed sculptured surfaces, its proved good flexibility and efficiently in all of its stages, the results have been implemented for machining one of these surfaces [fifteen intermediate layers, semi-finished layer, and finished] using 3-axis vertical CNC machine. The proposed rough machining algorithm reduces the machining time as compared with contour tool path by 15% for case study two and reduces the NC file size 52% for case study three.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2244
2258
https://etj.uotechnology.edu.iq/article_32027_e0210c1a7e148c0d9b39c9859e1f9db1.pdf
dx.doi.org/10.30684/etj.29.11.13
Design of a Nonlinear Robust Controller for Vibration Control of a Vehicle Suspension System
YasirKhudhair
Abbas
author
Muhsin
N.Hamza
author
Shibly
Ahmed Al-Samarraie
author
text
article
2011
eng
The suspension system is the main tool to achieve ride comfort and drive safety for a vehicle. Passive suspension systems have been designed to obtain a good compromise between these objectives, but intrinsic limitations prevent them from obtaining the best performances for both goals. In present work, a robust controller for the active suspension system has been designed to get the best performance of the suspension system. The nonlinear robust controller is designed based on adding an integrator to a two-degree-of-freedom quarter-car model. The control action will decouple the upper sprung mass subsystem from the lower (unsprung mass) subsystem after a certain small period of time. As a result, by adjusting the control law parameters, the dynamical response for the sprung mass subsystem is freely specified (the damping ratio and the natural frequency for the sprung system after decoupling). The simulation results, which are carried out by using Matlab/Simulink, proved the effectiveness of the proposed control law. The results confirmed that the sprung mass system is decoupled from the lower unsprung system and unaffected by the change in sprung mass and the road excitation disturbance. Additionally, the time history of the sprung mass response is according to a mass spring system response with the desired damping ratio and the natural frequency.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2259
2273
https://etj.uotechnology.edu.iq/article_32032_ea9fec72adfbe58c6c684b27205a802c.pdf
dx.doi.org/10.30684/etj.29.11.14
Optimizing the Conditions for the PVC Playing- Balls Fabrication
Suhair
Mohammad Yaseen
author
Ali
Najem Abdullah
author
text
article
2011
eng
Although PVC polymer is one of the cheapest plastics that are widely used in industry. The conditions of PVC processing industries are still industrially and commercially confidential and uncovering it is still industrially and commercially confidential and uncovering it is not easy. This work aims to make processing conditions available to whom interest. This has been achieved by studying the parameters associated with production process and determine the optimum conditions which are necessary to get best quality and more economical product. These parameters are included: 1- Mixing equal quantities of both rigid and flexible PVC will give requiredhardness for product with degree of polymerization 600-700. 2- Addition of 3% stabilizer (tribasic lead sulfate) works on raising temp. Of process to 250 centigrade without polymer burning or dissociation. 3- Addition of 55% plasticizer (dioctyl phthalate) to polymer (melting point of polymer Tm = 90-100 centigrade and glass transition temp. Tg = 170 Co) decreases Tg below room temp. 20-25Co .As a result of this work, product has enough strength and good flexibility to charge with required volume of air. 4- Coloring of product by 2% Titanium oxide to give bright white color. Oven temp. Is 150-180 Co.
Engineering and Technology Journal
University of Technology-Iraq
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29
v.
11
no.
2011
2274
2281
https://etj.uotechnology.edu.iq/article_32033_c11b907352ff16f3d5598c178c65b631.pdf
dx.doi.org/10.30684/etj.29.11.15
33% RZ-DPSK 10 Gb/s WDM Transmission
Rasha
Hassan Abbas
author
Ali
Y. Fattah
author
text
article
2011
eng
200 GHz-spaced 16-channel 40Gbit/s WDM signal transmission is proposed in Cband using 33% return-to-zero differential-phase-shift-keying (RZ-DPSK) format over a 5 spans of dispersion shifted-Anomalous fiber link. A parametric run on each span fiber length is performed (from 25 km up to 100 km). The performance of 16 40 Gb/s 33% RZ-DPSK WDM channels is analyzed using the “Optical Simulation “ software. While, the nonlinearity results related to optical fiber system have been simulated. Results that are given in this work are obtained using MATLAB R2009b (version 7.9.0.529).
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2282
2297
https://etj.uotechnology.edu.iq/article_32036_4b760086d4b2241abef58d0cd8f78b1f.pdf
dx.doi.org/10.30684/etj.29.11.16
Numerical Simulation for Laminar Natural Convection with in a Vertical Heated Channel
Hussein
Majeed Salih
author
text
article
2011
eng
A numerical investigation has been performed to estimate the induced flow rate for a laminar natural convection flow of air in a vertical channel with isothermal walls conditions (one hot and another is cold). The two-dimensional governing equations have been solved using finite volume method. The coupling between the continuity and momentum equations is solved by using the SIMPLE algorithm. After the validity of the present code by comparing results with these of previous study for the similar conditions, solutions have been obtained for Prandtl number of 0.7, aspect ratio of (4 to 20) and wall temperature difference of (10 to 30). The effects of the changes in these parameters on the induced flow rate, Grashof number and flow patterns within the channel have been predicted. A mathematical form of flow rate correlation is presented for these cases.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2298
2311
https://etj.uotechnology.edu.iq/article_32038_dbab89eb7b1f784c96affc06ba082905.pdf
dx.doi.org/10.30684/etj.29.11.17
Removing 0.5 Hz Baseline Wander From ECG Signal Using Multistage Adaptive Filter
H.
H. Abbas
author
text
article
2011
eng
This paper deals with the implementation of software system to remove 0.5 Hz baseline wander noise from the ECG signal using multistage adaptive filter. At start, a single stage adaptive filter has been implemented and the performance of the implemented system has been checked for changing the values of noise levels, the convergence factor of the adaptive algorithm, and the length of the adaptive filter. From testing results it is clear that the performance of the implemented system changes by the above factors values. Then an adaptive filter with the best values for the above factors has been used as a prototype to build multistage filter. The resulted multistage adaptive filter has been tested to prove its capability to remove 0.5 Hz baseline wander noise as compared with single stage adaptive filter. From testing results, it is clear that multistage filter gives better results than single stage filter.
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2312
2328
https://etj.uotechnology.edu.iq/article_32040_e97556d8c1cec4ef364a056dc79e1601.pdf
dx.doi.org/10.30684/etj.29.11.18
Theoretical and Experimental Study of Pressure Prediction in Crevices Region between Piston Rings for Diesel Engine
Hayder
Q. Alwan
author
text
article
2011
eng
An engine of Zeetor type Z – 6901 of three compression rings is employed in this investigation to accomplish the experimental work. The indicator diagram i.e. P=ƒ(α) is recorded at different engine speeds. The present work elucidates the measurement and indication of gas pressure within the combustion chamber as a function of crank angle. The study contains the prediction of pressure in inter-ring volume pressure behind piston ring during engine operation. For verification of a mathematical model a static test rig apparatus is designed in order to measure the inter-ring volume pressure within the range of compression pressure i.e. 1bar to 33.8bar. The comparison between mathematical and experimental results show good agreement
Engineering and Technology Journal
University of Technology-Iraq
1681-6900
29
v.
11
no.
2011
2329
2345
https://etj.uotechnology.edu.iq/article_32044_efe1b057fe651759273990d8471847a1.pdf
dx.doi.org/10.30684/etj.29.11.19