Journal of Techniques

This study has been performed at the Daquq region to indicate the suitability of the ground water which is important source for civil uses. The samples taken from (19) wells at different locations and tested at laboratories of north gas company at Sept.-2008.The tests included (electrical conductivity ,total dissolved solids ,PH-value ,concentration of some anions) were all conducted four each sample . The results revealed that surveyed ground water were free from pollution and almost suitable for domestic use. Some investigated parameters appeared to be near the recommended limits set by Iraqi standards, while others exceed the recommended values that the chemical treatments are necessary.

In this research a formula for computing the theoretical extrusion for solid phase of polymers has been concluded. The Formula was adapted from the Ward equation
( by the use of lower bound theory ) by adding the redundant Work effects ( WR ) and strain rate in the flow stress effects (σf) to the formula .
The theoretical results of the pressure (p) for the new formula was testing and compared with the theoretical results of the Ward equation and with the practical experimental results . The comparison parameters were the effect of reduction ratios ( R%) ( 7.01 , 21.55 , 43.7 , 58.7 , 71. 3 ) % and semi – die angle
( α°) ( 7.5° , 15° , 20° , 25° , 30°) on the extrusion pressure at the strain rate equal to
( 33x10-4/sec ). Practical Experiments have been done in two kinds the high density polyetheiline and low density polyetheline through nine cone dies on pressure instrument by use Grease oil
The results of the modified formula showed that the results in the reduction ratios and the semi – die angle gave an approaching (96, 92.9) % compared with the practical experimental results respectively.
The new formula gave a better agreement Compared Ward equation which gave approaching ( 92 , 84.4 ) % respectively from practical experimental Results .

In this proposal research , some aspects and important properties in manufacturing of advanced composite materials reinforced by fibers will be studied ,these aspects show as introduction to some important properties of polymeric composite materials reinforced by fibers related with its composition and some mechanical properties (Tension ,Impact, Compression, Flexural, Hardness, etc) .The objective of this research is to study the effect of using different reinforcement percentage of fibers on mechanical properties for composite material consist of vinyl ester resin reinforced by glass fibers(°0) (E) type with (2.6 g/cm3) density which included impact , tensile, compression , flexural strength , and hardness where we extracted the mechanical properties for vinyl ester resin before reinforced by fibers, then we reinforced the resin by different weight percentage from glass Fibers(20%,40%,60%) and studied its effect on the above mechanical properties .

The corrosion resistance of gray cast iron 3 %C and plain carbon steels (with different carbon contents such as low carbon steel 0.2%C , medium carbon steel 0.45%C , and high carbon steel 0.65%C ) have been studied in soil contain sulfur for 960 hours exposure time . The weight loss technique is used as a function of the corrosion resistance.
The results show, that the corrosion rate in a wet soil is larger than that in a dry soil, and the corrosion resistance decreases with the increase of carbon content in the carbon steels. The corrosion rate of gray cast iron resembles to the corrosion rate of 0.2% and 0.45% carbon steels in the same corrosion media.

The main aim of this research is to study the effect of (2.5 ،5.0 ،7.5،10.0) % by cement weight of Styrene Butadine Rubber (SBR) emulsion used for concrete mixes، its depend cement weight ratio to the total aggregates weight of ( 0.305، 0.222 ،0.167 ( and w/c ratio by ( 0.42 ،0.44 ،0.52 ) respectively ،and it is shown their effect on some mechanical properties (compressive strength ،splitting tensile strength،flexural strength) and total absorption .
The test results showed clear improvement in some mechanical properties by using 10% (SBR) modified concrete at the test duration of (180) day for three groups its ratio of (26.7 ، 18.8 ,11.0) % (34 ,23 ,17 ) % and (20, 18, 14 ) % for each compressive strength ,splitting tensile strength and flexural strength compared with the three referential Mixture for the same duration respectively and clear drop in total absorption its ratio of (53 ,44،30) % for the three concrete mixtures of (0.305 ،0.222 ،0.167 ) respectively at the duration of (90) days compared with the three referential mixtures with the same test duration .

The research topic of reducing energy consumption to approach the limits of thermal comfort inside the buildings and call to make buildings more suitable for local climate in the hot dry regions, and we have paid for that is what we found happening in some of the construction methods used in some areas of Iraq, including the city of Mosul, Sulaymaniyah and Dohuk, Erbil and Kirkuk, which many the use of the concrete block and solid in construction work, and to provide information which would reveal the impact of the use of building materials and design practices to improve the thermal performance of the approach of thermal comfort. To achieve the aim of the research has been the use of the scale (Mahoney) Amended and of climatic data for the city of Mosul, to gain access to indicators and general recommendations and detailed, and build a virtual model and the extrapolation of these indicators through an analytical study of (32) and the situation is different in two phases, thermal performance and to identify and compare the performance of default under the model indicators:
1- Changing of construction constituents.
2- Changing of plan direction.
3- Adopting the compact plan.
4- Reducing the rate of openings to 15% of the area of the wall.
The research has shown that there is positive improvement in reducing energy load in case of changing the index of construction constituents from nearly 13% to 63%. and in the case of combined indications it would reach to nearly 66% and to higher costs of insulation and wrapping which might reach to 86%, which showed that the rejection method using solid blocks will change a lot of the need to adapt to the artificial energy buildings and the shortcut from the energy consumption

The suggested programming package which is designed in Visual Basic-6.0 language enables the user to simulate the electrical theorems through three levels of electrical circuits with different level of complexity of network size and solution requirements. In addition of the user can analyze the circuit from several chosen points of load resistance limited on the circuit or network to be analysis.
The research depends upon Alessi and stephen model as one of instructional design models used to the simulation .The research is evaluated by taking opinions of the experts in instructional technology, electrical power engineering, computer fields and others included a sample of the targeted group which represent the first stage students of Electrical Department in Technical Institute of Nasseriya.The most important conclusions can be summarized as follows:- 1- Simulation is an active approach to simplify electrical engineering subjects because the simulation approach helps the user to imagine the electrical circuit behavior which is not seen without it .
2- The simulation activities are enough to achievement the specified behavior.
3- Simulation programs decreases the work and time which are spent by student on training compared with classical training methods

The effects of different variables on the metal plates (plates for house's numbers) are studied using designed and manufacturing the die using CAD/CAM system. The study was done in two stages: The first stage is for computer works, in which the die is designed and drawn by AutoCAD program for two dimensional drawing. Then the preparation is done to achieve the process by SURFCAM program, in which had both drawing and operation. In this study the operation only is used for generating the numerical control codes automatically for die and plates with very small periods time in which for classical way needed more time and may be have several mistakes and generation the code for single type only but in the present study it can be generated any types of codes for dies of simplicity and/or complicated shapes and for any type of machines without to new inputs.
After the generation of the codes, the die is prepared for final work on the milling machine (CNC) (Computerized Numerical Control).
The second stage, which consists of several steps, parts of die are prepared for programmed milling machine and the die had been operated on by the special press in order to do the embossing process to form the metal plates. Several parameters can be changed (thickness of plate, type of process, and the heat treatment) as an application for die's work. The last step is analyzed for effective stresses on the plates by ANSYS program.
Three plates from Aluminum are used with different thickness (P1=0.5 mm, P2=0.7mm, P3=0.8mm) with dimensions (10x15.5 cm) and the pressure force is applied to get the embossing process with amount (30, 40, 50) bar and the results obtained indicate that the plate with thin thickness (P1) have difficult formation compared with the other samples (P2, P3) in which several cracks are formed, the plates are unaccepted to be used to produce the numbers of houses and vice versa the plate P2 which have the best ability and the plate P3 with high thickness have little cracks in which made him the best one in the product of these plates. When the applied pressure is increased the number of cracks increased too, and the best pressure was 30 bar. The experimental results are agreed with the theoretical results that get from ANSYS for stress analysis for three plates.

The effect of furnishing street space are formal apart of the important elements in the construction environment which characters almost it being small in size and scale compared with the urban environment , but it exists with huge numbers , so it has functional and visual importance that effect the environment . The previous literatures didn’t focus on furnishing street space elements value and the consistency of these elements gives beauty to the construction environment . This research aims to build a clear vision about the effect of furnishing street space elements on harmony and consistency of construction environment . The research assumes that achievement of harmony and consistency of construction environment depended in high degree on furnishing street space elements . The researchers concluded that furnishing street space elements by two type the industrial and the natural are considered to be integrated with the urban space and in reaction between its formal provided the rest for the street space users and formal a wholly system has big significance to achieve the harmony and the consistency in the construction environment and that didn’t studied previously

This study is carried out in an important agricultural region which put under dry farming system for long time. The region characterized by wavy and undulating topography. The results shows that the total phosphorus content is relatively high. This is attributed to parent materials and to low activity of weathering processes, which indicates the low degree of soil development. It’s content exhibits decreasing with depth because the affect of organic matter.
Such distribution indicate slow vertical movement and little effect of topography except pedon (42) which shows higher content of total phosphorus because the addition processes of the phosphorus from the surrounding area, and the effect of the organic matter. Organic phosphorus Shows the same trend of variation and show better affect of topography on distribution than other forms, which marked the depth of percolating water. Mineralogical phosphorus exhibit the same behavior with low rate.

The aim of this research is to study the influence of inlet mixture temperature on the spark ignition engine performance and exhaust emissions.
For theoretical study we prepare computer program to calculate the performance variable and exhaust composition using Thermodynamic Model.
As for practical study we used spark ignition engine type (TD-110) single cylinder, four stroke, work gasoline fuel. The inlet mixture temperature increased and decreased by increasing and decreasing inlet air temperature using an air conditioning instrument type (T110D) made by Italian Didacta factory . we insert intake air manifold into the outlet unit of air conditioning instrument in order to achieve six inlet mixture temperature (10,20,40,50,60,70) . The mean results of investigation in comparison to the operating (20 were as follow:-

1. We observed through comparison between theoretical and practical results, that there is an error about (22%).
2. Increasing inlet mixture temperature from (20-50) improve in fuel consumption and thermal efficiency about (16%, 14%) consecutively.
3. Regarding the exhaust emissions the results show that the concentration of (CO,HC& ) decrease about (1.5%,17%,%12.5) consecutively with increasing inlet mixture temperature from (20-50) .

The paper studies the use of frame resizing by zooming as a compression technique to achieve Constant Bit Rate (CBR) live video transmission. Most video compression techniques provide a relatively constant level of decoded video quality, but, at the expense of Variable Bit Rate (VBR) outputs. This will result in an inefficient usage of the available bandwidth, and the decoder has to buffer a suitable amount of data before it can play the received stream. This results in a variable overhead delay depending on the variation in the bit rate. Conversely, a CBR technique can efficiently occupy the available bandwidth with constant overhead delay and buffer size, but, at the expense of variable decoded video quality.
The Peak Signal to Noise Ratio (PSNR) is used in the computer simulation tests to measure video quality. The tests show that variation of video quality in a CBR system employing frame resizing is still acceptable (PSNRav>25 dB) for resizing factors greater than 40%. Moreover, the tests show that the resizing technique, when compared to conventional video compression techniques, is more immune to additive Gaussian noise, since it involves an interpolation process which averages out part of the added noise

In wireless communication system it can achieve increases in the reliability of data reception without bandwidth expansion by using antenna diversity. Space-Time Block Codes (STBC) can achieve the full diversity gain with very simple decoding but cannot get perfect performance for coding gain. Trellis-Coded Modulation (TCM) is a kind of channel coding with improving the coding gain. Therefore, concatenation of STBC and TCM is a combined channel coding to achieve both diversity gain and coding gain advantages. In this paper the performance of TCM is evaluated alone and so for STBC with two transmit and one received antennas, as well as concatenated STBC with TCM over frequency flat fading channel. The simulation results illustrates that concatenation system is robust for various level of Signal to Noise Ratio (SNR) in multipath fading channel. Simulink implementation has been done for such system

In this study, the problem of steady laminar natural convection heat transfer and fluid flow inside U-shaped enclosure has been analyzed numerically. The U-shaped enclosure was differentially heated. The problem was investigated for multiple Rayleigh numbers ( ) and aspect ratios ( ). The mathematical model of the considered problem is formulated in terms of fully elliptic Navier-Stockes and energy equations. A numerical solution based finite volume approach is obtained. A documented results are introduced in terms of contours maps of streamlines and temperatures. Also the results are presented in terms of local and average Nusselt numbers. The results show that the aspect ratio has a significant effect on the induced multi cellular flow for high Rayleigh numbers. Also the results show that the rate of heat transfer is increased with the increase of Rayleigh number and decrease with increasing of the aspect ratio(A

For some applications it is usually recommended to have high heat resistant elastomer materials. Compounds with blend of EPDM (Ethylene-Propylene Rubber) and VMQ (Dimethyl polysiloxane Rubber) or silicone rubber of medium and high VA (Vinyl Acetate is 45% and 70% in VMQ) along with ingredients are used in this paper to fulfill high heat resistant compound. Synthetic fabric was used as reinforcing agent with the rubber compounds. The physico-mechanical properties, rheometric characteristics, abrasion resistance and adhesion property with different textile members were studied for this selective blend. Ageing study was carried out on a vulcanized samples. Overall properties of EPDM/VMQ blends based on VMQ with high AV content are found to be better compared to blends based on VMQ with medium VA content.

Recently there has been a great deal of interest in the application of spread spectrum systems. However, the performance of the robust spread spectrum system detector depends on the selection of the spreading signal. This paper is intended to provide the basic concepts of a proposed spread spectrum system based on two features. The first one implies the use of the spread spectrum based on Rossler chaotic sequence to minimize interference caused by other systems to secure the information transmission. The second concept clarifies the use of a chirp signal to achieve high data transmission rate within a limited bandwidth. Furthermore, performance of the proposed system is simulated in the presence of AWGN as well as frequency offset is applied to notice and limit its effect. Bit error rate (BER) is computed to evaluate the system confidentiality

The paper presents the experimental study of mobilizing friction between soil and concrete. The series of laboratory tests have been carried out on coarse and fine-grained soils. Using statistical approach, the best fitting relationships describing the mobilized friction dependence on displacement have been determined for different soil types. It was found that the behaviour of sand soil unlikes that of clayey soil, so for each type of the soil behaved differently regarding the mobilized friction and displacement. In addition to that, the critical horizontal displacement, at which the whole friction is mobilized, is larger for fine sand than coarse one. The critical horizontal displacement for the normally consolidated clay exceeds more than twice the value for sand. The overconsolidation ratio for clay soil increases the mobilized shear resistance and reduces the displacement

The Genetic Algorithms can be considered as modern active way for finding optimum solution for many engineering problems as electronics , power , communication engineering. This optimum location has been detected with a low number of iteration . this optimazation can be used for many civilian applications such as location of electrical power station , location of communication center or other to reduce the price/ km for transmission line . this optimization problem has been run with a special genetic algorithm called ( Gas play ground ) with suitable genetic input file.

An effective image coding technique which involves transforming the image into another domain with Ridgelet function and then quantizing the coefficients with modified threshold. Ridgelet functions are effective in representing functions that have discontinuities along straight lines. Normal Wavelet transforms fail to represent such functions effectively. This paper shows the application of wavelet analysis to image compression. All of the four steps in compression namally transform, quantization, and coding. achieved quantization part deals with the translation of large set of data into a smaller set. On the other hand, coding deal with the representation of these transformed and quantizaed data into bits. Acomplete implementation, with remarkable results, are presented. The results obtained from the combination of ridgelet gave much better performance than that obtained from the Wavelet ,and multiwavelet Transform with ridgelet transforms.

This paper introduce the construction of multi-band phase shifter based on steps sweeping phase-locked loop .The desired phase shift can be selected to have any value between In addition multi-phase shift output can be also obtained simultaneously. The phase shifter can be operated over a wide range of input frequencies.The maximum error of the phase shift is which is controlled by the division factor .

The proposed high frequency inverter circuit is devoted to analyze the behavior of contactless inductive powering transmission system with large air separation. Typical applications are for automatic battery charging station and for power supply of inductively powered electric vehicles and other movable consumers. The paper investigates the influence of geometrical and electrical parameters on power transmission with air-separation of (1000mm) through zero-switching state simulation of the proposed high frequency inverter. Contactless powering transmission systems operate at resonance frequency with a proper choice of the resonance capacitor on the primary and secondary side, the contactless system represents an ohmic load for the primary inverter. Therefore switching events take place at zero current (ZCS) without auxiliary commutation elements, which is an important precondition for reaching higher transmission frequencies. For this application a special inverter was developed. The phase–shifted controlled bridge at the primary side is equipped with Insulated-Gate bipolar transistors and freewheeling silicon carbide schottky diodes. Because of their ultra low reverse recovery charge, the operation behavior is much better as compared with fast silicon diodes.

The work presented in this paper concerned with the design and implementation of the power line frequency monitoring and archiving system based on the personal computer. The frequency measuring board was implemented and the interfacing process with the personal computer via serial port was performed. In order to monitor the frequency readings a graphical user interface program has been implemented together with data archiving program. Experimental results show an accurate and reliable system

The basic purpose of this research is focused to assess the possibility of using a white gravel as a coarse aggregate in the asphaltic mixes which practically in turn reduce the eventual construction costs of the asphaltic roads in many cities at the middle of Iraq through evaluating their physical properties.
Three different local types of aggregates are selected from the middle and northern-west of Iraq and used in this laboratorial analysis; those are White Crushed Gravel (WCG), White Rounded Gravel (WRG) and Black Uncrushed (Rounded) Gravel (BRG).
Strength, extraction and stripping tests are conducted in evaluating the resulted physical properties of the produced asphaltic mixes.
The results of the laboratorial tests indicate that White Crushed Gravel (WCG) which is used as a coarse aggregate in the asphaltic mixes yields maximum Marshal Strength and minimum Marshal Flow of 8.3KN and 2.2mm respectively associated with an asphaltic mixing content of 5% of the total mixing weight, whereas BRG yields minimum Marshal Strength and maximum Marshal Flow of 6.8KN and 2.4mm respectively occurred with asphaltic mixing content of 4%.
White Crushed Gravel (WCG) gives an Index of Retained Strength of 94.7% with 5% asphaltic mixing content whereas Black rounded Gravel (BRG) yields 91.4% Index of Retained Strength occurred with 4% asphaltic mixing content.
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An investigation was carried out study the effect of temperature and pH on corrosion rate using carbon steel rotating cylinder electrode in deaerated 1M NaCl solution at pH 3, 6 & 8 and temperatures 25, 50 & 80 C˚ for one hour. It was found that corrosion behavior of carbon steel was greatly influenced by rotation speed at lower pH whereas at higher pH there was a less effect of rotation speed on the corrosion rate and became constant till reached critical speed .The critical speeds in this study were 4000, 3000 & 2000 rpm at 25, 50 & 80 C˚ respectively . This was attributed to the fact that at pH3 the corrosion rate was activation-controlled. At pH3 the corrosion rate was increased from (16.347mpy)50c̊ at static conditions, till reached critical speed, to (88.926mpy)50c̊ due to the formation of protective hydroxide film on the metal surface which restricts access of H2O to the surface .Also study the effect of temperature on corrosion rate by derived mathematical model for experimental data

A mathematical model for groundwater motion in three dimension hydrogeologic heterogeneous media at Al Hawija Area (4222km2in extent) is developed. The theory of superposition is applied at the media and the results are verified using a theoretical background of Darcey’s Law and Theis Equation for the confined and unconfined aquifers at the area. Under the highlight of the current conceptualization study, the resulted superimposed drawdown variation of theoretical and numerical solutions shows a good identity at the beginning of pumping up to 2500 days and acceptable identity in variation beyond these periods for the unconfined aquifer. Whereas the variation of drawdown with time for both theoretical and numerical solution shows an acceptable coincidence before one year and the two solutions begin to deviate with time beyond that under the effect the existing hydraulic boundaries for the confined aquifer.