Print ISSN: 1681-6900

Online ISSN: 2412-0758

Volume 27, Issue 15

Volume 27, Issue 15, November 2009, Page 517-2884


Over Voltage Transient Protection Network Design

Miqdad T. Younis; Nidhal Y. Nasser

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2711-2718

Transient over-voltage caused by lighting, switching large inductive loads,couples on to data communication or instrumentation signal lines and introduce series fault alarm conditions and damage instrumentation electronics. Most of the semi-conductor devices and other sensitive electronic equipment are easily damaged with transients of high amplitude with fast rise time, with threshold energy levels in the range of micro joules to mill joules. Hence, it is very essential to protect the system by hardening the input power supply lines,
input/output data and communication lines utilizing various transient suppression techniques to make the system immune to transients. If an electronic system designer intend to build a protection circuit a custom design will be desirable, as the interface or inter-connection could be more effective for the intended environment.

Performance Analysis of Nonlinearities in WDM Systems

Fikrat Abdul Kareem

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2719-2729

Wavelength division multiplexing (WDM) is a technology that enables the
transmission of several optical signals simultaneously at different carrier wavelengths on a single fiber and the separation of the signals by wavelength at the receiving node. While WDM is very attractive, it has some disadvantages also. One such disadvantage is the appearance of fiber nonlinearities. With the use of multiple channels, several miliwatts are injected into the fiber. Such high powers lead to the
appearance of different nonlinear effects in the fiber, mainly the Stimulated Raman scattering (SRS), Stimulated Brillouin scattering (SBS), Four wave mixing (FWM), and the Cross Phase Modulation (CPM). These nonlinear effects lead to the degradation of system performance.
In this work the performance analysis of nonlinearities in the WDM systems was implemented using Mat lab-(7).

A Correlation Between Dynamic and Static Pile Load Test Results

Kais T. Shlash; Hussein H. Hussein

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2730-2737

Three selected bored piles executed at Basrah area were tested both by
static and dynamic pile test procedures in order to correlate their results when evaluating the piles capacities. The correlation showed that the results are close to each other in terms of load- settlement relations, but on the other hand, end bearing capacity and skin friction values obtained by the dynamics tests are far from the real behavior of piles. The reason may be due to lack of experience of
crew that supervises the dynamic tests. They have to practice more dynamic tests and should build accumulated knowledge about the dynamic method of testing piles. The time is still early for the dynamic tests to replace the classical static test when evaluating piles capacities.

On The Nonlinear Key Generator Design Using Unit-Step and Trace Functions

Raghad Kadhim Salih

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2738-2750

The paper presents a proposed method with an algorithm which has been
written in Matlab language for designing a nonlinear key generator, which is denoted by (US-TR), using unit-step function and trace function from Galois field of order 2N (i.e. GF(2N), (N≥2)) to Galois field of order 2 (GF(2)). The proposed generator produces a binary sequence of period (2N -1)where N is a composite number, with high degree of complexity and good randomness properties. The advantage of the new nonlinear generator is the output sequence which has high
degree of complexity to increase the security of this generator concerning the designed feature that limit the ability of anti-jammer when it uses as a key in cipher systems or in spread spectrum digital communication system. This paper has useful properties of the trace function. Moreover, Illustrative examples are given for determining the output sequence with its complexity of the proposed generator and good results are obtained

Study Of The Chemical Durability And Hazardous Ionic Leaching Of(Soda-Lime) Glas

Sanaa A. A. Hafad; Abd al khalaq F. Hammod; Huda A. Hussain

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2751-2759

Huge amounts of glass materials being applied in medical, pharmaceutical
and chemical aqueous solutions; this requires the study of chemical stability of glass at the exposed surfaces with these solutions where the leaching takes place. The leaching of the glass ions will transport these ions to the solutions stored in the glass containers; leading to changes in the chemical composition in the order of part per million that causes hazardous effect with time. The present work investigates the leaching chemical properties of the soda-lime Iraqi glass containers. The effect of the pH of contact solution and
annealing of glass on leaching rates is studied. Ionic leaching shows lower rate with PH of the solutions at the ‘safe zone’: (6>PH>8.5). Annealing increases the leaching rates and reduces of the chemical durability of glass. Increasing annealing time led to further increase the leaching rate. In addition, the increase in the exposed surface area also increases leaching rates.

The Dynamic Coefficients and Elastic Deformation with Thermal Effect For Cylindrical Pivot Tilting 5-Pad Bearing

Muhannad Z. Khelifa

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2760-2774

The paper describes the results of theoretical study of the tilting pad bearing consist of five pads each pad can be titling 0.2o about a cylindrical pivot at high speed of rotating journal. The total oil film thickness includes elastic deformation with thermal effect had been estimated. By using finite element method to solve the Reynolds equation for dynamic load, from this solution generated pressure,
components of oil film forces and moments are expressed as functions of journal coordinates, dynamic coefficients (stiffness and damping coefficients) these coefficients of oil film can be determined by differentiation of the oil film force finally elastic deformation of pad surface was obtained. This paper also includes the study of many
parameters such as pivot offset, preload factor, direction of load (load on pad and load between load) and dynamic coefficients were presented as functions of Sommerfeld number. Results show that good bearing performance when the pad preload factor is increase and pivot offset decreases.

PI Controller for The Heating Process in The Real Time System Based on LAB VIEW 8.2 Packages

Ahmed Sabah Abdul Ameer Al-Araji

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2775-2791

This paper experimentally investigates the control of the heating process in a water tank. A trial and error method is used to find the best system response depend on the tuning parameters of the PI controller based on a Matlab simulation package in order to replace these parameters in the real time digital PI controller system based
LabVIEW package. The PI control action in the real time system technique shows more oscillation in comparison to that the PI simulation control action. Simulation and real time results for heating process experiment has successful for maintaining water tank temperature.

The corrosion of (Fe,Zn,Cu) Metals in 3.5%Nacl solution under Different Flow Conditions

Qasim M. Abbas; Shatha A. Sameh; Jamal M. Ali

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2792-2805

As the practical importance of protection of industrial equipments from
corrosion the need arises to study the corrosion of different metals as Carbon steel, Zinc and Copper measured their corrosion current and potentials have been investigated in 3.5% NaCl solution at 40ºC for different flow conditions (Re = 5000, 10000 and 15000), by using commercial metal pipe as test specimens cylindrical. Potentiodynamic polarization studies have been performed for single metals. It was found experimentally that the corrosion of metals (Fe, Zn, Cu) is under
diffusion control since the corrosion current density (iL) increases and corrosion potential (Ecorr.) shifts to less negative with increasing velocity, the limiting diffusion current density is independent of the nature of the cathode material, but it depends on
the Reynolds number. The corrosion current density of metals (Fe, Zn, Cu), shows a good agreements with other works, and reasonable agreement with Culburn –Chilton and Paulson correlations are also observed at different Re.No.

Effect of Using Header Compression Method in TCP/IP Protocol Over HDLC in SCADA System

Sarcot N. Abdullah; Bassim Abdulbaki Jumaa; Omar A. Mohamad

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2806-2813

Most of the header information remains constant over the life-time of the connection. For TCP connection many fields are constant and others change with small values. To initiate compression of the headers of a packet stream, a full header is transmitted over the link. The compressor and decompressor store most fields of this full header as reference. The reference consists of the fields of the headers whose values are constant and thus need not be sent over the link at all, or change little between consecutive headers so that it uses fewer bits to send the difference from the previous value compared to sending the absolute value. To improve interactive response time and to decrease the header overhead on the system we used the method of Compressing Protocol Headers (TCP/IP). Also it is used to compress the HDLC header. The simulated communication protocols have been tested between two PCs and the time delay, throughput and utilization have been measured.

Speed Control of Hydraulic Motor System with Swashplate DC-Controlled Pump

Majid A. Oleiwi; Amjed J. Humaidi

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2814-2834

In a previous study, speed-controlled hydraulic motor system has
employed a DC motor for changing the swashplate angle of a variable
displacement piston pump. However, the speed control has been performed by a flow modulation valve which is permitted to bypassing the flow of the hydraulic motor when the speed exceeds the set value. In the present work, another speed control configuration has been proposed with the pump and hydraulic motor are permitted to perform reversal actions. The conventional proportional, integral and derivative (PID) controller has been introduced to manipulate the speed error such
that it could achieve the required performance. The specification required by the PID controller is to reach the command speed as fast as possible with minimum peak overshoot. Also, the effectiveness of the suggested controller against changing of system parameters is considered. The modeling of the speed control system components is detailedly presented, including the dynamic of swashplate,
and one can easily see that the system is of a nonlinear nature. The state space representation of the complete system has been developed and the program codes are listed inside an m-file, which is instantaneously called by an s-function within SIMULINK library.

Thermal and Electrical Properties of Silica-Mullite-Grqphite Composite Fired at Low Temperature

Mohsin E. Aldokheily

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2835-2843

Silica - mullite powder sieved through 100 mesh, mixed with graphite at
certain proportions and placed in a steel mould, then subjected to ≈ 40Mpa .After air- drying for 24 hours the specimen buried in carbon and fired at 1150 ◦C overnight. DC resistance was measured by the method of two probes. The percolation threshold was not sharp , instead it starts from 10.5% graphite ratio up to 21% were it resembles the conductivity of graphite alone . Resistance and reactance analysis were carried out at three frequencies (0.55, 1.5, 5.0) kHz. The specimen was subjected to heating/cooling cycle and the change in DC resistance value (TCR) was found to be less than 1%for each 100◦C rise in temperature

Formation and Characteristics Study of Nanostractured Solar Cell

Yasmeen Z. Dawood; Bassam G. Rasheed; Ali H. Al-Hamdani

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2844-2852

Electrochemical and photoelectrochemical etching technique have been
employed to produce nanostructured solar cell. Various preparation conditions were examined. The I-V characteristics measurements were adopted to study effects of these parameters on the solar cell efficiency. We found that when shorter laser wavelength used to illuminate the porous layer during the etching process, the conversion efficiency of the solar cell increases . While doping the porous layer with phosphorous increases the nanostructured solar cell efficiency
by 30 %

Removal of Phenol Pollutants by Modification Molecular Sieves 13X

Laith S. Sabri; Jabir Shanshool

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2853-2862

Molecular sieves type 13X was modified by treatment with saturated solution of urea or thiourea and adding of sodium silicate as binder to give homogeneous admixture in approximate weight percent, 20% urea or thiourea, 30% binder, and 50% MS13X. The samples were dried and shaped in cylindrical particles of about 5mm diameter and 4-8mm length. The FTIR studies show some interaction between the added urea and thiourea with the original substrates. These are mainly hydrogen band type interactions through –NH2 moiety with –OH group of framework oxygen in
the substrate or with adsorbed water. The urea displayed more significant interaction with MS13X than thiourea. Molecular sieve 13X and its admixtures with urea and thiourea showed good ability to remove phenol from water. The urea modified sample, which has the largest surface area, was the best adsorbent for phenol followed by thiourea treated sample. Excellent degree of phenol removal, greater than
98% was achieved by using 0.2 l/h flow rate of 10ppm phenolic solution and 56cm bed length at 300C. The increasing of inlet phenol concentration in water affected largely the driving force and the rate of adsorption, resulted also in higher capacities. While the percentage removal of phenol was decreased by fixed other operating conditions

Evaluation of Horizontal Flow Roughing Filtration Performance

Zainab S. Habeeb; Sataa A. Al-Bayati

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2863-2878

The HRF was studied by using pilot plant. This pilot plant was designed
and applied in Al – Wehda Water Treatment Plant which treats the raw water of Tigris River in Al – Karradah in Baghdad city. Design characteristics of the pilot HRF are 5.5m length × 1m width × 1m depth , the HRF length consists of inlet ( 0.5 m ) , outlet ( 0.5 m ) and three compartments ( 2m , 1.5m and 1m ) filled with three different size of gravel ( 15mm , 10mm and 5mm ) respectively . The HRF was continuously operated (24 h in a day) during the period from 15/
May / 2007 to 15/ July / 2007. Operated done in two stages. In the first stage, raw water (free from any addition) was used, with three different flow rate 1.3, 1.1 and 0.9 m3/h. While in the second stage, coagulated water (raw water + alum) was used, with flow rate 1.3 m3/h. To assess the performance of HRF, the required tests were carried out. These tests are Turbidity, S.S, Temperature, pH and Bacteriological tests. The results of tests were analyzed statistically. The mean of
removal efficiency of turbidity for first stage with discharges 1.3 , 1.1 and 0.9 m3/h is 92% , 94% and 95% respectively , and for second stage is 97% . These results indicate the high performance of HRF in turbidity removal.

Design, Construction and Testing A Laser Power Comparator

Jassim Kadim Hmood; Haidar Ali Nasser; Mohamed Saleh Ahmed

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 2878-2884

A laser power comparator prototype that can be utilized in laboratories has been designed constructed and tested. The system consists of three main electronic circuits: the laser comparator electronic circuit, sign detector and phase inverting circuit, and an analog-to-digital readout display circuit. The comparator has two detectors each receives a particular input signal. Two input signals will be compared and the output will be displayed on a digital readout (or on an oscilloscope). Power difference up to 0.1mW is achieved.

The Mechanical Properties of Aluminum Matrix Composites

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 517-523

This work is production of aluminum matrix composite by powder metallurgy method .The samples have done when aluminum powder was used as a matrix in purity of (9.99%) and silicon carbide(α-SiC) as reinforcement material, the particle sizes were used which (125μm) at weight percentage (7.5% - 10% - 15%) from silicon carbide for each particle size. The purpose is to improve the hardness and wear properties of matrix .It was found that the hardness is increased with increment of the amount of added particles, due to the hardness of silicon carbid particles. From the wear test, it is found that the wear resistance increase with increasing the weight percentage of SiC particles, but the wear rate increase when the applied load increase for all the particles size and additional percentage. Also, it is found that when the sliding velocity increases, the wear rate also increases, but the best results were found in samples reinforced with (SiC) particles

Study the Effect of Ultra Violet Rays (UV) on Some Mechanical Properties of Epoxy Composites

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 524-538

Epoxy resin type (Ep-10) was used as a matrix for composite materials,
with Glass fibers, aluminum powder and silica powder as reinforcement with volume fraction (Vf= 30%). Four types of composites were prepared:-
(1) Epoxy reinforced with glass fiber and aluminum powder.
(2) Epoxy reinforced with glass fiber and silica powder.
(3) Epoxy reinforced with aluminum powder.
(4) Epoxy reinforced with silica powder.
Research subject was implied studying some of mechanical properties for
composite materials that used in the research, in different weathering conditions including Ultraviolet Radiation (UV). Mechanical properties that be studied is: Young’s modulus (E), Impact Strength (I.S.), and Compressive Strength (C.S.). The results showed that the best
mechanical properties were for hybrid composites reinforced with fibers and particles (Ep+G.F.+Al) ,(Ep+G.F.+SiO2), such that, they have higher: Young’s modulus, Impact strength, and compressive strength in all weathering conditions

Survey of Ground and Surface Water Quality in AL-Khadimiya Town

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 539-556

According to the lack of water in AL-Khadimiya town due to the sabotage
justify happened in the infrastructure of town like water distribution system of potable water as a result the residents of the concerned town used the ground water in all life activities as second source.
13 sampling wells have been chosen in that area ,4 sample collected from Tiger river each sample represented different area around AL-Khadimiya and chemical study included for the soil of different depth to examine their water . The experimental works at the laboratory shows the increase in Turbidity value .Hardness of calcium and magnesium, chloride, sulphat &Bacteria account (Coli form) the high values of the pervious testes made water an portable and with
respect to the irrigation of plants, it is accepted with medium salt &Chlorides, the spiel result at the laboratory tests for the Tiger river is not acceptable for drinking not for irrigation is accepted.

The Properties of Produced Concrete by Using Fine Aggregate with Sulphate Content Higher Than Iraqi Specification Limits

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 557-569

The sulphate problem in fine aggregate increases with time in Iraq and the construction companies became face a lot of difficulties to find fine aggregate within the specification with regard to sulphate content. This paper studies the possibility of adjusting fine aggregate content in concrete mixes to facilitate using fine aggregate with sulphate content higher than the Iraqi specification limit (0.5%), but the total sulphate content of the mix will be within the specification (I Q S 45, 1984). One reference mix is used in this study with fine aggregate conformed to the specification for sulphate content ,and three other mixes are used with different fine aggregate content and also different sulphate content .Some tests are conducted for these produced mixes to fined their mechanical properties. This study shows the ability of using fine aggregate with sulphate content up to
(2.33%) to produce mixes with a compressive strength ,splitting tensile strength ,and modulus of rapture not less than (80%),(94%), (84%) respectively as compared with the refrence mixe at age of (180) days .

Effect Chlorophyll Pigment on Specific Gravity And Tensile Properties For Natural Rubber And Protect It From UV Ray

Engineering and Technology Journal, 2009, Volume 27, Issue 15, Pages 570-577

The aim of this research to use extracted natural pigments which extracted plants such as chlorophyll as plasticizer and stabilizer material by simple method. The sample of rubber was prepared with adding different percent from chlorophyll pigment (0-25)pphr to study the effect of this material on properties of natural rubber. When we added chlorophyll pigment, we fined chlorophyll act as plasticizer that
interact between rubber chains and decrease interaction molecular forces that decrease specific gravity (from 0.997 to 0.986), tensile strength (from 13.295 to 8.384)MPa, modulus of elasticity (from 2.745 to 1.312) MPa. This mean is chlorophyll pigment is doing as lubricant material to facility the moving of molecules chain one on anther and act as stabilizer that protect rubber from UV light because it
absorbed UV light and transmit it to no harm heat .Therefore this work exists with a good replacement for synthetics plasticizers and stabilizers materials avoiding their toxicity and their highly cost.