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Engineering and Technology Journal

مجلة الهندسة والتكنولوجيا

ISSN: 16816900 24120758
Publisher: University of Technology
Faculty: Presidency of the university or centers
Language: Arabic and English

This journal is Open Access

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The Journal aims to disseminate knowledge in the fields of Engineering, Technology and Sciences .All the researches will submit to the scientific evaluation procedures of publishing and documentation. The journal under takes only the publishing of the new researches that had not been published previously on other journals or debated in conferences.

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Engineering and Technology Journal
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ENGINEERING AND TECHNOLOGY JOURNAL
Scientific Refereed Journal Issued by University of Technology, IRAQ
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جمهورية العراق –بغداد
الجامعة التكنولوجية- مجلة الهندسة والتكنولوجيا- ص.ب. 35010
Email: etj@uotechnology.edu.iq
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http://uotechnology.edu.iq/tec_magaz/EN/index.htm
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Republic of Iraq, Baghdad
University of Technology, Engineering & Technology Journal.
P.O.Box.35010
Email: etj@uotechnology.edu.iq

Email: uot_magaz@yahoo.com
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Table of content: 2011 volume:29 issue:16

Article
Prepare of Mapping the Distribution of Schools in Kut City Using Geographic Information System (GIS)
أعداد خرائط توزيع المدارس في مدينة الكوت بأستخدام نظم المعلومات الجغرافية (GIS)

Authors: علي كريم شايش
Pages: 650-663
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Abstract

The increased rates of urbanization have resulted in doubling the number of schools in in the city randomly, which resulted in building schools lacking the most appropriate standards required like being fit with the convenient environmental and health conditions or being away from natural and human dangers, because of the great abilities that the geographic information systems gives which help in finding the most appropriate solutions and making the best decisions, especially with regard to processing and analysis of spatial information. Thus, the current research aims at using GIS in assessing the current status of school sites in all stages of primary intermediate and high school, according to a set of natural, human and social standards. As well as the employment of GIS to document the locations of the current distribution of schools in the city to produce digital maps of sites and the pattern of distribution of schools subject to update, then it suggests amending some of the sites according to the degree of suitability criteria in research. To achieve these aims, the research depends on the data available at the directorate of education in wassit, in addition to the field survey to identify the location of schools accurately using GPS and updating the data available. The research finds the existence of concentration in the distribution of schools which is concentrated in some regions, random in others or regular in others. In general, this distribution may not reflect a situation similar to the distribution among all regions in the city.

Keywords

- Schools --- GIS --- Kut City.


Article
Text Files Compression using Combination of two Dictionary methods (Specific dictionary for specific language and LZ77 Approach)
ضغط ملفات النص بدمج طريقتين من طرق القاموس ( قاموس خاص للغة محددة مع LZ77)

Authors: أحمد حسين عليوي
Pages: 664-671
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Abstract

In this paper we suggest combination between two dictionary methods. Specific dictionary (for specific language) and LZ77. The dictionary is used for replacing any word in it by its two Bytes index. A words not exists in the dictionary is written without changing preceded by four bits for length of this word. A modification was made on this approach for reducing the file to minimum size. Because of each word was replaced by two bytes (which are substituted in any appearance for this word in text), LZ77 can be used efficiently. Before this, the file is arranged specially in order to use LZ77 optimally for minimizing the data. This approach is tested on real text files and verifies it’s successful.في هذا البحث اقتراح لدمج طريقتين من طرق القاموس وهما طريقة القاموس المتكامل للغة يستخدم القاموس للتعويض عن كل كلمة موجودة (معرفة) في القاموس العام للغة . LZ محددة و 77 والكلمات الغير موجودة في القاموس تبقى على حالها مع كتابة عدد (Two Bytes) معينة ببايتين من البتات قبلها للاشارة إلى طولها. قمنا بعدة تعديلات على هذه الطريقة للحصول على اقل حجم ممكن للملف. كل كلمة يعوض عنها ببايتين وسوف يعوضان عن تلك الكلمة في أي مكان ترد فيه الكلمات عن الناحية العملية بقت على ) LZ هذه الكلمة ٠ فلذلك تم استخدام الطريقة الثانية 77 ترتيبها). قبل ذلك قمنا بترتيب الملف بطريقة خاصة استخدمناها بحيث نستطيع الاستفادة من طريقة لتقليل البيانات الى آفل حد ممكن. هذه الطريقة جريت على ملفات نصوص حقيقية وأثبتت (LZ77) نجاحها

Keywords


Article
Studying the Sensitivity of Bacteria Isolated From Respiratory Tract Infections To Peanut and Various Antibiotics
دراسة حساسية البكتريا المعزولة من الإصابات النفسية للفول السوداني ومختلف المضادات الحيوية

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Abstract

The sensitivity of bacteria isolated from respiratory tract infections for various antibiotics and peanut was studied. These bacteria included 5 gram- negative species: Klebsiella pneumoniae (1 isolate), K. oxytoca (1 isolate), Pseudomonas aeruginosa (6 isolates), Escherichia coli (2 isolates) and Neisseria meningitidis (1 isolate), while gram- positive bacteria included: Staphylococcus aureus (6 isolates), Streptococcus pneumoniae (6 isolates), Micrococcus antarcticus, coagulasenegative Staphylococci (CNS) and Corynebacterium spp., one isolate of each. We tested the sensitivity of bacteria to 16 antibiotics as follows: Tobramycin (10 ìg), Ceftazidime (30 ìg), Vancomycin (30 ìg), Ampicillin (10 ìg), Cefaclor (30 ìg), Ofloxacin (5 ìg), Cloxacillin (1 ìg), Cefalothin (30 ìg), Erythromycine (15 ìg), Clindamycin (2 ìg), Oxytetracycline (30 ìg), Enrofloxacin (5 ìg), Neomycin (30 ìg), Amoxicillin/Clavulanic acid (30 ìg),Ampicillin/ Cloxacillin (30 ìg) and Cefotaxime (30 ìg). Also the sensitivity of bacteria to ethanolic extracts of peanut (Arachis hypogaea) was tested. We found that S. aureus was resistant to most antibiotics (13 antibiotics), and was sensitive to vancomycin, ofloxacin and enrofloxacin. As well as S. pneumoniae which was sensitive to the same antibiotics above in addition to ampicillin/ cloxacillin, while was resistant to 12 antibiotics. K. oxytoca was more resistant than K. pneumoniae and both were sensitive to enrofloxacin. Both E. coli and P. aeruginosa were resistant to 13 antibiotics and both were more sensitive to tobramycin and ofloxacin . N. meningitidis resisted 9 antibiotics , where as all of CNS , M. antarcticus and Corynebacterium spp. were sensitive to most antibiotics. When we studied the sensitivity of bacteria to ethanolic extracts of Arachis hypogaea ,four isolate of S. aureus were sensitive with zones of inhibition 7- 11 mm and two isolates were negative. The growth of two isolates of S. pneumoniae was inhibited with inhibition zones of 8 and 10 mm, while 4 isolates were not inhibited. The herb extract recorded zone of inhibition of 8 mm in only one isolate of P. aeruginosa.

Keywords


Article
Study of Some Structural, Optical Properties of ZnS Thin Films Deposited by Chemical Spray Pyrolysis Method Study of Some
دراسة بعض الخواص التركيبية والبصرية الأغشية كبريتيد الزنك المحضر بطريقة الرش الكيميائي الحراري

Authors: بان خالد محمد
Pages: 682-691
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Abstract

In this research we prepared ZnS thin films by Spray pyrolysis method with thickness(300nm) on a glass substrates and study its structural and optical properties . The result of (X-Ray ) diffraction showed that the films have a polycrystalline structure , The Absorption and The transmission as a function of Photon Energy for ZnS films had been studied , The investigated of energy gap of the direct allowed transitions of ZnS film showed a value of (3.53eV). The optical Absorption coefficient , extinction coefficient , and have been also study Refractive Index, as a function of Photon Energy.

Keywords


Article
Particle Swarm Optimization and Genetic Algorithm for Tuning PID Controller of Synchronous Generator AVR System

Authors: Fadhil A. Hassan --- Lina J. Rashad
Pages: 3256-3270
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Abstract

Proportional Integral Derivative (PID) controllers are widely used in many fields because they are simple and effective. Tuning of the PID controller parameters is not easy and does not give the optimal required response, especially with non-liner system. In the last two decades many intelligent optimization techniques were took attention of researchers like:Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) techniques. This paper represented the non-linear mathematical model and simulation of the synchronous generator with closed loop PID controller of AVR system. The traditional PID tuning technique is proposed as a point of comparison. Two of intelligent optimization techniques: PSO and GA are proposed in this paper to tune the PID controller parameters. The obtained results of the closed loop PSO-PID and GA-PID controller response to the unit step input signal shows excellent performance with respect to the traditional trial and error tuning of the PID controller.


Article
Simulation Study of Wired/Wireless Fieldbus Systems Using Store and Forward Mode

Authors: Sufyan T. Faraj Al-Janabi --- Ali Shuaib
Pages: 3271-3290
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Abstract

Fieldbus is a specific class of LAN technology, through which the communication process in industrial applications is integrated. The extent of using the wireless communications in most applications, leading to design hybrid wired/wireless fieldbus systems is based on standard PROFIBUS protocol. Because of the difference in physical media such as bit rate and/or frame format between wired domain and wireless domain, there is a need to use a method to overcome traffic congestion that may occur in the intermediate systems as a result of the heterogeneity in the physical media. Within this work the intermediate systems (repeaters) are suggested to work as store-and-forward mode. The main objectives of this work is to develop simulation tools for the hybrid wired/wireless PROFIBUS architectures in order to perform behavioral study of such network protocols. The use of our developed simulation tools has indeed enabled us to test different network configurations and different parameters settings more easily, cheaper, and faster than in a real application.


Article
A Proposed Secure Protocol for E-Mail System Based on Authentication and Hash Function

Authors: Muna Mohammed Al-Nayar
Pages: 3291-3301
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Abstract

Internet has opened new channel of communication enabling an e-mail to be sent to a relative thousands of kilometers away. This medium of communication opens doors for virtually free mass e-mailing, reaching out to hundreds of thousands users around the globe within seconds, so e-mail becomes the most popular form of communication today. E-mail systems have suffered from increasing attacking problem that threatens the validity and integrity of communication. Many different approaches for fighting this attack have been proposed, ranging from various sender authentication protocols to encrypt the message itself. This paper demonstrates a promising protocol. The proposed protocol ensures the authentication and integrity of the data and avoids the problem of key distribution or breaking by using multiple random keys generated automatically during communication session.


Article
The Effect of Waste Ceramic Materials ( Iraqi Stones Dust Powders ) on The Mechanical Properties of Epoxy Resin

Authors: Fadhil A.Chyad
Pages: 3302-3312
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Abstract

Using waste materials, which have a high pollution on the environment, as an improvement to the properties of a weaken material such epoxy resin become a good achievement. Iraqi stones dust powders have been used to improve the mechanical properties of epoxy resin. Impact strength and fracture toughness from impact test, Young`s modulus from tensile test, Shore hardness, fracture toughness and thermal conductivity have been investigated. The percentages of the ceramic powders have affected all the above properties and increased the values of them about twice. The highest values were at 12% and then decreased. Also the particle size of this powders has affected these properties, where the lowest particle size (25ìm) has the best values.


Article
Determination of Some Mechanical Properties of Unsaturated Polyester Reinforced with Glass Fiber and Plam Fiber

Authors: Wafaa AbedAlkazem Zkaer
Pages: 3313-3319
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Abstract

In this work a composite materials is prepared containing matrix of polymer (unsaturated polyester) reinforced with different reinforcing materials (glass fiber + plate fiber) in different values of volume fraction %. All samples for to mechanical tests were prepared by hand layup process. The mechanical tests can be classified into: bending, tensile strength, tensile strength at break, elongation at break and hardness. The study of mechanical test shows that the mechanical properties increase with the increase in volume fraction.


Article
Effect of MnO-4 Anion Inhibition on Corrosion of (70%Cu-30%Zn) Brass in Salt and Basic Solutions

Authors: Mervit M. Al-Jnabi
Pages: 3320-3330
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Abstract

This research involves study effect of MnO-4 anion addition as inhibitor on the polarization behavior of (70%Cu-30%Zn) alloy in salt and basic medium ( 0.6 M NaCl & 0.6 M NaOH) by potentiostatic method where Tafel slopes and corrosion rate (Rmpy) and inhibition efficiency (El%) for each salt and basic environments were measured . Result of the tests shows that the values of Tafel slopes and corrosion rate decreases with adding the MnO-4 anion in two solutions, the Inhibition efficiency of 70%Cu-Zn30% alloy in NaOH solution more than that observed in NaCl solution. which means that the basic media is more corrosive Cu-Zn alloy even after the addition of inhibitor.


Article
A Particle Swarm Optimization (PSO) Based Optimum of Tuning PID Controller for a Separately Excited DC Motor (SEDM)

Authors: Alia J. Mohammed
Pages: 3331-3344
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Abstract

The PID algorithm is the most popular feedback controller used within the process industries. It is robust easily understood algorithm that can provide excellent control performance despite the varied dynamic characteristics of process plant. But the tuning of the PID controller parameters is not easy and does not give the optimal required response, especially with non-liner systems. In the last years emerged several new intelligent optimization techniques like, Particle Swarm Optimization (PSO) techniques. This paper deals the non-liner mathematical model and simulation for speed control of separately excited D.C. motor with closed loop PID controller. The conventional PID tuning technique is represented as a point of comparison. The intelligent optimization technique: PSO is proposed to tune the PID controller parameters. The obtained results of the closed loop PSO-PID Controller response shows the excellent response with comparing to the conventional PID, a good results gives in PSO-PID Controller. The simulation results presented in this paper show the effectiveness of the proposed method, which has got a wide number of advantages.


Article
Effect of Fly and Dust Ash Additions on Hardness and Wear Resistance of Composite Metal Matrix (Al-Si-Mg)

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Abstract

The current paper deals with the preparation of bars with a length of about 13 cm and 2.5 cm diameter from MMC materials. These composites consists of cast (Al-Si-Mg) as a matrix that reinforced with fly ash (0.454 ìm) or fly dust (0.620 ìm) in relative weights (2, 4, 6, and 8%) respectively. Both of composite materials samples were manufactured by casting method (Vortex method). Vortex method has been used successfully to obtain a homogeneous distribution of reinforcement particles. Samples were classified into two categories according to the type of reinforcement particles. The results showed that the wear rate of the samples depends heavily on the working conditions. Which increases with increased load and download time.The results also showed superiority aluminum alloy reinforced fly ash compared with the aluminum alloy reinforced with dust flying. Furthermore, a significant increase in the hardness and wear resistance for all samples prepared with increasing added particles for the purpose of reinforcement.


Article
Dielectric and Thermal Properties of Carrot Fibers –Epoxy Composites

Authors: Wafaa A. Hussain
Pages: 3359-3367
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Abstract

Epoxy composites were prepared with two sizes of carrot fibers in different weight percent (10%, 20%, 30% and 40%) by hand lay-up technique. The dielectric constant and dissipation factor (tanä) of pure epoxy resin and composites were measured in a frequency range of 50 Hz to 5 MHz with increase fibers content, dielectric strength (breakdown voltage) and thermal conductivity were evaluated as a function of fiber content. The dielectric constant and dissipation factor values were found to be higher for fiber reinforced system than the pure epoxy. The dielectric strength values decreases and the values of thermal conductivity increases with fibers content.


Article
Effect of Freezing-Thawing Cycles on the Physical and Mechanical Properties of Some Sedimentary Rocks Located Near Mosul City

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This study is aimed to investigate the surfacial deterioration of some common sedimentary rocks near Mosul city as a result of freezing-thawing cycles on physical and mechanical properties of two types of Limestone denoted as (L1 and L2), Sandstone (S) and Mosul Marble (M). Physical and mechanical tests include; uniaxial, triaxial compression tests, point load test and the indirect tensile strength (Brazilian test) have been performed on both the fresh specimens and the specimens subjected to a number of freezing-thawing cycles (5, 10, 15 and 20). Test results showed that the freezing and thawing is a process of physical deterioration, a significant reduction in different percentages in uniaxial and triaxial compressive and tensile strength was observed in all the rocks tested. A little variation was observed in the slaking durability indices (IS-D) of (L1, L2 and M) rocks among three conducted cycles at fresh state, while (S) rock showed high percent loss of about 45.81% in its durability. On the other hand, the water absorption percent of the tested rocks showed a clear increase with the increase of number of freezing-thawing cycles.


Article
Generate Animated CAPTCHA Based on Visual Cryptography Concept

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Abstract

CAPTCHA is a standard security technology. To date, the most commonly used are various types of visual CAPTCHAs, in which a challenge often appears as an image of distorted text that the user must decipher. The proposed scheme is used visual cryptography encryption protocol to encrypt CAPTCHA image in perfectly secure way, such that only the human visual system can easily decrypt the CAPTCHA image with animated arrangement. Numbers of blurring image process are implemented on the CAPTCHA images, to make this test difficult for current computer systems. The new animated CAPTCHA is more secure than the current versions and easier for humans to pass.


Article
Improvement of Soil by Waste Tires Addition

Authors: Falak O.Abas --- Mohammed .O.Abass --- Raghad.O.Abass --- Shymaa K.G.
Pages: 3417-3428
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Abstract

Low able fill material is a self – leveling– compacting one; these types of material rapidly gain acceptance and application in construction utility earthworks. The use of scrap tires as a reinforcement element is an attractive solution that combines the advantage of improving soil mechanical behavior with environmental concerns. The present work describes an experimental study on replacing sand aggregate grain size with wastes rubber and plastics at different mixing ratio (6, 18, 30) % wt. respectively to support technical feasibility of muddy soil by using wastes materials then compared with commercial additives (carbon fiber) afterward check their hydrodynamical properties (E.L, P.L, hydrometer, compaction, and sp.gr) of prepared compacting improved soil mixtures. Experimental results indicate that crumb rubber have successfully used to produce a light weight flow able fill ( 1.2 to 1.6 g/ cm3 ) than other additive waste plastic and carbon fiber based on the characteristic properties (E.L, P.L, hydrometer, compaction ) as follows: Have 65% for rubber samples than other additives of 45% and 55% molecules respectively for hydrometer test, 2 Gs for rubber than 1Gs for other additives; and 560 g/cm3 compaction for rubber additive than 520 g/cm3 for other additives carbon fiber and waste plastic.


Article
Message Coding and Compression with Artificial Neural Networks

Authors: Hasan M. Azzawi --- Hassan A. Nasir --- Ali K. Naher
Pages: 3429-3437
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Abstract

The need to overcome data preprocessing inherent in much of the classical data coding techniques commonly available led to the search for a free, easy-to-use, but flexible and powerful method. Artificial Neural networks have been attracting more and more researchers since the past decades. The distinct properties, such as learning ability, nonlinearity, fault tolerance, generalization etc., make it suitable for information protection, such as data encryption, data authentication, data detection, etc. In this paper a simple and low-cost coding method based on neural networks is proposed to be used to patterns compression. The goal of the developers is to build a tool able to store and send a coded and compressed message. The formed two-dimensional patterns are coded and compressed using the multilayer neural network with Back-propagation training algorithm. Hidden layer outputs of a trained network are sent as two-dimensional data, which represents the encoded vectors. To reconstruct the original patterns, this requires the output weights matrix and the output nodes functions which are unknown and not available in the encoded sent vectors. A compression rate of about 6:1 has been achieved.

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Article
Using Fractal Model in Documents' Security

Authors: Ali .A. Saeid
Pages: 3438-3450
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The research aims to build graphical models of complex formation and morphology which can be used to secure paper documents from attempts of fraud, especially those trying to expose them to scanning. Therefore, the scanned version will differ in features from the original one, particularly the part that contains the seal (the decorative form). The forms were generated by using a model of Koch's star; keeping in mind that points of the lines of the new form will be generated by using Brsenham's theory in order to generate the straight line.

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Article
A Study for the Influence of Change in Ratio of Cross Sectional Area to Constant Perimeter of Thermosyphon's Condenser

Authors: Ali D.Salman --- Israa S.Ahmed --- Waleed Y.Shehab
Pages: 3451-3467
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This experimental study investigated the change in cross-sectional area (csa) of thermosyphon's condenser to it's a constant perimeter (RAP) and effect of that at the thermal performance. Geometries shapes deform from circular to elliptical and flat to make a change in csa at a same perimeter of all geometries shapes where a different value of RAP are got. At each RAP a different rate of heat input in evaporator and different filling ratio of working fluid (distill water) are applied. Threshold angle (working angle) where the condensate of distilled water vapor begin to return to evaporator, this angle are examined with the horizontal level for three geometries shapes (three RAP). The results indicated that the flat two phase closed thermosyphon( FTPCT)(low RAP value) and elliptical two phase closed thermosyphon (ETPCT) had a higher and more stable heat transfer coefficient h (condenser air side) with the high and mid filling ratio from than of the circular two phase closed thermosyphon( CTPCT). That refer to more useful length of condenser to absorb heat from evaporator and prevent it from causing a rise in temperature. The high filling ratio with low rate of heat level in evaporator lead to unuseful area in thermosyphon's condenser and lowering its pressure, while low filling ratio with high rate of heat caused a chaotic flow inside TPCT and rising the evaporator and condenser temperatures.

Table of content: volume:29 issue:16