Table of content

Journal of Engineering

مجلة الهندسة

ISSN: 17264073
Publisher: Baghdad University
Faculty: Engineering
Language: Arabic and English

This journal is Open Access

About

The Journal Engineering was issued in 1986. It was Stopped from 1990 – 1997 because of the economic blockade. It restarted publication after the fourth scientific engineering conference for it published the papers that were accepted in the conference.
It is a scientific engineering journal refereed by specialized and qualified professors in most of the engineering fields and those Specialists in the issued by the college of Engineering university of Baghdad .It was serenely publibued , but from 2011 it has issued of monthly for the numerous papers submitted to the journal to publish their papers in this scientific journal in addition to some of the Arabs professors because the journal is considered one of the valued journals in the Arabic homelan .
Many professions were the head editor of the journal from its first issue. The first one was prof.dr. Laith Ismail Namiq then prof.dr. Mohammed A.Alawis ,prof.dr.Ali A Al – kilidar prof.dr. Abdul-Ilah Younis and currently Prof.dr.Qais S. Ismail.

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Iraq
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Email: joengbag@uobaghdad.edu.iq

Table of content: 2011 volume:17 issue:6

Article
"Modern Technological Approaches and Contemporary Airports Terminals’ Design
التوجهات التكنولوجية الحديثة وتصميم محطات المطارات المعاصرة

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Abstract

It is not hidden the role of technology in modern and contemporary airport terminals design, the second half of the twentieth century have a large number for airports in which technology represent a metaphor for contemporary culture that modified the mechanism of thinking, designing and production. This research aims to determine and its applications’ ways in contemporary airport terminals design . Then the design of airport terminals _which considered one of the most important building type_ is not only related to the ideas of functions performance or buildings shapes as separated processes to produce this challenging building type, which is charged by functional encumbrances and is a symbolic building . There is inclusive overlapping between design issues of contemporary airport terminals, and the new technology. which distinguished the new approaches of contemporary airport architecture, and has led to formulate a research problem considered about the gab of knowledge in distinguishing the role of the new technological approaches for contemporary airport terminals, and its nature and its effect on design process, the hypothesis formulated from this problem is:" the compatibility of contemporary technology fundamentals and contemporary airport terminals design issues and the integration of its main systems, that produces new approaches affected by the use of the technological dimension as a method of thinking and producing and as a tool for expression

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Article
الحلول المنشئية وجماليات الجسور المعاصرة

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In recent years, bridges became one of the most difficult achievements and most accurate in terms of design, it’s used to pass over, or to enjoy the surrounding scenery, some got its importance for its history and some for the changes it made to certain area, in addition to the high technology used in others in which it became a symbol to the development and technology of that specific area. The structural systems helped to achieve connection and allowed them to extend to unbelievable distances. This role played by Bridges grew attention to these structures and made them Special to its designers and users not only for its structural engineering but for its architecture too. As a result of this distinction it became necessary to study their Aesthetic impacts on its surrounding in general and on the receiver in particular. Therefore, studies on the bridges aesthetics and its artificial considerations have increased, as it became a need as well as a symbol within open spaces. The designer would deal with a several optical elements during the designing process, which would be chosen with high accuracy to create a piece of art that fits the expandable vital role, in addition to applying the functional limitations of the design. The research approaches the definition of Aesthetics in bridges and demonstrates the world wide applied concepts related to the subject to define some Hypothesis testing vocabulary, the research also concluded a general rule that (Aesthetics cannot be separated from structure in bridge design because Aesthetics in all applied concepts is (a concept of form, architectural and artificial structure


Article
The signified and signifier between the object and its shadow and the possibility of their separation in the urban scene
الدال والمدلول بين الشكل وظله وإمكانية الفصل بينهما في المشهد الحضري

Authors: Ammar Salim Dawood
Pages: 277-296
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Abstract

People used to see shadow as an accidental result of light and object and as a sign of the object's existence .For example, when we see shadow we know an object exists. What happens if shadow is created without the object's existence?. Dismantling the relation between the object and its shadow, in addition to the possibility of making the shadow as an independent design factor, constitute the research's problem. The background relationship between the object and its shadow is presented according to the "signified – signifier" duality which has been extensively theorized by semanticists ,as it is made clear in Baflov's theory about the "conditional reflex" .This theory highlights the possibility that the "signified" has the same effect on the recipient as the " signifier". The research then focuses on the "shadow";its concept and characteristics ,and it specifies the main mechanisms by which the shadow could replace the original object .These mechanisms are employed to form what the research calls" shadow drawing elements";defined as design elements aiming at drawing shadows to provide formal richness by alternative means which would add beauty and interest to the urban scene in particular and the artistic work in general.

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Article
Architectural Space in Hera Kingdom and Sasanyain Empire
الفضاء المعماري في مملكة الحيرة والحكم الساساني أنذاك

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The research problem can be identified in the limitedness of the studies that allocate the comprehensive historic continuity of the Mesopotamian architecture during the Hera and sasanyain eras and at the architectural space level on the consideration that it is the heart of architecture in all its compositional and detailed items. Thus, the research aims at clarifying if there were any continuity in the Mesopotamian architecture during the Hera and sasanyain eras, and consequently, clarifying the levels of this continuity if it were on the whole or part level in architecture, then, identifying the changes that it has been through in order to know how to achieve continuity of contemporary architecture along its historical course. In order to verify this hypothesis, the architectural space has been studied. This study has managed to specify the items of the spatial continuity in the Mesopotamian architecture at the level: 1- The spatial formation 2- the spatial relations 3- the architectural elements 4- the detailed treatments Moreover, the research has reached the general conclusions and it recommends a number of recommendations at the applicable, academic and epistemological level


Article
The Heat Transferred Reduction From Building Roof Which Exposed to Environmental by using Grasses and Water (Experimental Study)
تقليل كمية الحرارة المنتقلة من سقف المبنى المعرض للبيئة باستخدام تقنية المسطحات الخضراء أو المائية (دراسة تجريبية)

Authors: Atif Ali Hasan عاطف علي حسن
Pages: 311-324
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Abstract

The object of this paper, is to study the thermal behavior of building roofs which covered by grass (used 50 mm sand as a base for American grasses and watered weeds by 0.0004 L/sec.m2 for growth) or sprinkle the water (0.0004 L/sec.m2) on that roofs, therefore , a room of dimensions (4.5 x 4.5 x 3) m was build in 3rd floor in building at Baghdad city (33.2°N) with thermal insulation of 200 mm thickness for other room sides and using Air – conditioner 1.0 ton of refrigeration to afford the standard thermal comfort, and measured the roof surfaces temperature from 5:00 Am to 10:30 Pm (18 hr/Day) during May to September month, it was found that, the grasses in roofs building was saved 53% from electrical energy for cooling purpose, while sprinkle the water on roofs saved 38 % only


Article
THE STATIC ANALYSIS OF COMPOSITE AIRCRAFT WING-BOX STRUCTURE

Authors: Azhar K. Farhood --- Ahmed A. Ali
Pages: 1378-1390
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Abstract

In this paper, the static analysis for finding the best location of boxes inside the composite wing-box structure has been performed. A software ANSYS (ver.11) was used to analyses the Aluminum wing to find the maximum stresses reached in. These results are used as a base for the composite wingbox to find the numbers of layers and location of the box beam and its dimensions so that the composite wingbox may carry the same loading conditions in the Aluminum wing. Analysis showed that a composite wingbox having two boxes is better than the single or triple boxes wing based on stress to weight ratio. Mass saving of (40%) had been achieved when composite wing-box is used instead of Aluminum wing.


Article
An Experimental Investigation on Fatigue Properties of AA3003-H14 Aluminum alloy Friction Stir Welds

Authors: Asmaa M. Abdullah --- Dr.Ayad M. Takhakh
Pages: 1391-1400
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Abstract

AA3003-H14 aluminum alloy plates were welded by friction stir welding and TIG welding. Fatigue properties of the welded joints were evaluated based on the superior tensile properties for FSW at 1500 rpm rotational speed and 80 mm/min welding speed. However, there is not much information available on effect of welding parameters with evolution of fatigue life of friction stir welds. The present study experimentally analyzed fatigue properties for base, FSW, and TIG welds of AA 3003-H14 aluminum alloy. Fatigue properties of FSW joints were slightly lower than the base metal and higher than TIG welding.


Article
SIMULATION OF FLIGHT THROUGH GUST

Authors: Kareem Jawad Kadhum
Pages: 1401-1416
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Abstract

A flight simulation programme has been developed on a personal computer using Microsoft FORTRAN to simulate flight trajectories of a light aircraft by using Six-Degree-of-Freedom equation of motion. The simulation has been made realistic through pre-programmed the input to the control surfaces, atmospheric gust during the flight mode. The programme plays an important role in the evaluation and validation of the aircraft design process. A light aircraft (Cessna 182T) has been tested through free flight, gliding flight, flight with gust. The results show good trend and show that the programme could be dependent as a realistic flight test programme


Article
ORGANIZATION OF MEMORY CHIPS IN MEMORY SYSTEMS THAT HAVE WORD SIZE WIDER THAN 8-BIT

Authors: Omar W. Abdul-Wahab
Pages: 1417-1425
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This paper presents a method to organize memory chips when they are used to build memory systems that have word size wider than 8-bit. Most memory chips have 8-bit word size. When the memory system has to be built from several memory chips of various sizes, this method gives all possible organizations of these chips in the memory system. This paper also suggests a precise definition of the term “memory bank” that is usually used in memory systems. Finally, an illustrative design problem was taken to illustrate the presented method practically


Article
ESTIMATION THE 7 AND 28- DAY NORMAL COMPRESSIVE STRENGTH BY ACCELERATED TEST METHODS IN CONCRETE
تخمين مقاومة الانضغاط الاعتيادية بعمر 7 و 28 يوم بأستخدام طرق الفحص المعجلة في الخرسانة

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Curing of concrete is the maintenance of a satisfactory moisture content and temperature for a period of time immediately following placing so the desired properties are developed. Accelerated curing is advantages where early strength gain in concrete is important. The expose of concrete specimens to the accelerated curing conditions which permit the specimens to develop a significant portion of their ultimate strength within a period of time (1-2 days), depends on the method of the curing cycle. Three accelerated curing test methods are adopted in this study. These are warm water, autogenous and proposed test methods. The results of this study has shown good correlation between the accelerated strength especially for the proposal curing test method and normal strength using normal curing method at ages 7 and 28 day for the five different chemical composition of cement with different water to cement ratios equal to 0.45, 0.55, 0.65 and 0.75. Linear and nonlinear regression analysis show high correlation for the different types of the accelerated curing methods with coefficient of correlation (R2) more than 0.9


Article
MECHANISTIC EVALUATION OF LIME-MODIFIED ASPHALT CONCRETE MIXTURES

Authors: Amjad H. Albayati
Pages: 1444-1460
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Frequently, Load associated mode of failure (rutting and fatigue) as well as, occasionally, moisture damage in some sections poorly drained are the main failure types found in some of the newly constructed road within Baghdad as well as other cities in Iraq. The use of hydrated lime in pavement construction could be one of the possible steps taken in the direction of improving pavement performance and meeting the required standards.
In this study, the mechanistic properties of asphalt concrete mixes modified with hydrated lime as a partial replacement of limestone dust mineral filler were evaluated. Seven replacement rates were used; 0, 0.5, 1, 1.5, 2, 2.5 and 3 percent by weight of aggregate. Asphalt concrete mixes were prepared at their optimum asphalt content and then tested to evaluate their engineering properties which include moisture damage, resilient modulus, permanent deformation and fatigue characteristics. These properties have been evaluated using indirect tensile strength, uniaxial repeated loading and repeated flexural beam tests. Mixes modified with hydrated lime were found to have improved fatigue and permanent deformation characteristics, also showed lower moisture susceptibility and high resilient modulus. The use of 2 percent hydrated lime as a partial replacement of mineral filler has added to local knowledge the ability to produce more durable asphalt concrete mixtures with better serviceability.


Article
MODELING HOUSEHOLD TRIP GENERATION FOR SELECTED ZONES AT AL-KARKH SIDE OF BAGHDAD CITY

Authors: Su’ad Saba’ Al-Hassani --- Saad Issa Sarsam
Pages: 1461-1472
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Trip generation is the first phase in the travel forecasting process. It involves the estimation of the total number of trips entering or leaving a parcel of land per time period (usually on a daily basis); as a function of the socioeconomic, locational, and land-use characteristics of the parcel. The objective of this study is to develop statistical models to predict trips production volumes for a proper target year. Non-motorized trips are considered in the modeling process. Traditional method to forecast the trip generation volume according to trip rate, based on family type is proposed in this study. Families are classified by three characteristics of population social class, income, and number of vehicle ownership. The study area is divided into 10 sectors. Each sector is subdivided into number of zones so; the total number of zones is 45 zones based on the administrative divisions. The trip rate for the family is determined by sampling. A questionnaire is designed and interviews are implemented for data collection from selected zones at Al-Karkh side of Baghdad city. Two techniques have been used, full interview and home questionnaire. The questionnaire forms are distributed in many institutes, intermediate, secondary and, commercial schools. The developed models are total person trips /household, work trips /household, education trips/household, shopping and social/recreational trips/household and, person trips/person. These models are developed by using stepwise regression technique after the collected data being fed to SPSS software. Results show that total persons trips/household are related to family size and structure variables such as number of person more than 6 year age, number of male, total number of workers, total number of students in the household, number of private vehicles. This model has coefficient of determination equal to 0.669 for the whole study area. Also the results show that the home-based work trips are related to number of worker in the household, number of male workers in the household, number of female workers in the household and number of persons of (25-60) year age; this model has coefficient of determination equal to 0.82 for the whole study area. Home-based education trips are strongly related to number of students in the household and this model has coefficient of determination equal to 0.90 for the whole study area.


Article
BEARING CAPACITY OF SHALLOW FOOTING ON SOFT CLAY IMPROVED BY COMPACTED FLY ASH

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Low bearing capacity of weak soil under shallow footings represents one of construction problems. Kaolin with water content converges to liquid limit used to represent the weak soil under shallow footing prototype. On the other hand, fly ash, which can be defined as undesirable industrial waste material, was used to improve the bearing capacity of the soft soil considered in this research. The soft soil was prepared in steel box (36×36×25) cm and shallow square footing prototype (6×6) cm were used .Group of physical and chemical tests were conducted on kaolin and fly ash. The soft soil was improved by a bed of compacted fly ash placed under the footing with dimensions equal to that of footing but with different depth ratios. The results show that there is a noticeable improvement in the behavior of footing when improved by compacted fly ash. The improvement showed a decrease in settlement and increase in bearing capacity. The improvement ratio in bearing capacity was calculated by comparing the ultimate bearing capacity value when testing the kaolin alone with its value of kaolin improved with compacted fly ash at the same value of eccentricity. It is important to note that eccentricity values were chosen according to the rule of middle third of footing base(i.e.,e≤B/6). The improvement ratio was about (130%) in average value, that represent a good ratio of improvement


Article
REMOVAL OF COPPER ION FROM WASTEWATER BY FLOTATION

Authors: Farah I. Abed --- Ahmed A. Mohammed
Pages: 1483-1491
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Several industrial wastewater streams may contain heavy metal ions, which must be effectively removal before the discharge or reuse of treated waters could take place. In this paper, the removal of copper( II) by foam flotation from dilute aqueous solutions was investigated at laboratory scale. The effects of various parameters such as pH, collector and frother concentrations, initial copper concentration, air flow rate, hole diameter of the gas distributor, and NaCl addition were tested in a bubble column of 6 cm inside diameter and 120 cm height. Sodium dodecylsulfate (SDS) and Hexadecyl trimethyl ammonium bromide (HTAB) were used as anionic and cationic surfactant, respectively. Ethanol was used as frothers and the optimal removal conditions have been established. Successful removals about (98%) and (76%) could be achieved for copper ions with SDS and HTAB, respectively. Copper removal reached about 80% under the optimum conditions at low pH; at high pH it became as high as 98% probably due to the contribution from the flotation of precipitated copper. It was found that the presence of NaCl in the solution reduced the recoveries. Adding ethanol at 1% concentration increased the removal efficiency. From the results the rate of flotation was found to be first order


Article
PERFORMANCE CHARACTERISTICS OF METHANOL-DIESEL BLENDS IN CI ENGINES
مواصفات أداء خلائط ديزل- ميثانول في محركات الاشتعال بالانضغاط

Authors: Khalil Ibrahim Abaas
Pages: 1492-1501
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Owing to the energy crisis and pollution problems of today, investigations have concentrated on decreasing fuel consumption and on lowering the concentration of toxic components in combustion products by using non-petroleum, renewable, sustainable and non-polluting fuels. While conventional energy sources such as natural gas, oil and coal are non-renewable, alcohol can be coupled to renewable and sustainable energy sources. In this study, the combustion characteristics of diesel fuel and methanol blends were compared. The tests were performed at steady state conditions in a four-cylinder DI diesel engine at full load at 1500-rpm engine speed. The experimental results showed that diesel methanol blends provided 12.7% increase in brake-specific fuel consumption due to its lower heating value. The results indicated that methanol may be blended with diesel fuel to be used without any modification on the engine


Article
OPEN CIRCUIT HEAT EXCHANGER DYNAMICS DURING FLOW REDUCTION TRANSIENT IN THEIR SECONDARY LOOPS

Authors: Akram. W. Ezzat
Pages: 1502-1516
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An experimental and theoretical analysis was conducted for simulation of open circuit cross flow heat exchanger dynamics during flow reduction transient in their secondary loops. Finite difference mathematical model was prepared to cover the heat transfer mechanism between the hot water in the primary circuit and the cold water in the secondary circuit during transient course. This model takes under consideration the effect of water heat up in the secondary circuit due to step reduction of its flow on the physical and thermal properties linked to the parameters that are used for calculation of heat transfer coefficients on both sides of their tubes. Computer program was prepared for calculation purposes which cover all the variables that affect such type of transient mechanisms. The effect of the power density in the primary circuit and the water flow reduction percentage on the average temperature build up of the water in the primary circuit was investigated. The elapsed time required for the primary circuit average temperature to reach a steady state value was also calculated. These calculations were supported with experimental measurements conducted on a standard cross flow heat exchanger apparatus. The experimental results were compared with the theoretical results for certain power density value at different flow reduction percentages which show a reliable agreement. This relative agreement was necessary to consider the mathematical model with certain assurance for calculating transient parameters for higher power densities that are out of apparatus ranges. The results proved that water average temperature build up in the primary circuit has sharp tendency when the percentage of flow reduction in the secondary circuit reach 25% of its nominal values


Article
EFFECT OF TOOL SHOULDER DIAMETER ON THE MECHANICAL PROPERTIES OF 1200 ALUMINUM FRICTION STIR SPOT WELDING

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A friction stir spot welding (FSSW) process is an emerging solid state joining process in which the material that is being welded does not melt. In this investigation an attempt has been made to understand the effect of tool shoulder diameter on the mechanical properties of the joint. For this purpose four welding tools diameter (10, 13, 16 and 19) mm at constant preheating time and plunging time were used to carry out welding process. Effect of tool diameter on mechanical properties of welded joints was investigated using shear stress test and Microhardness of joint which welded was studied. Based on the stir welding experiments conducted in this study the results show that aluminum alloy (1200) can be welded using (FSSW) process with maximum welding efficiency (80%) shear strength using tool diameter(19mm) with rotation speed (900rpm).


Article
FREE VIBRATION ANALYSIS OF NOTCHED COMPOSITE LAMINATED CANTILEVER BEAMS

Authors: Ahmed N. Ouyed
Pages: 1524-1538
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The present work divided into two parts, first the experimental side which included the measuring of the first natural frequency for the notched and unnotched cantilever composite beams which consisted of four symmetrical layers and made of Kevlar- epoxy reinforced. A numerical study covers the effect of notches on the natural frequencies of the same specimen used in the experimental part. The mathematical model for the beam contains two open edges on the upper surface. The effect of the location of cracks relative to the restricted end, depth of cracks, volume fraction of fibers and orientation of the fiber on the natural frequencies are explored. The results were calculated using the known engineering program (ANSYS), the results obtained has been compared with those calculated analytically by (Sierakowski RL.), which have expressed the closest well also the comparison between the experimental results with that calculated by (ANSYS) has very well. The study shows that the highest difference in frequencies occur when the value of the fiber orientation equal to 0odegree, the effect of location of the cracks decrease when the cracks moving toward the free end and also shows that an increase of the depth of the cracks leads to a decrease in the values of natural frequencies


Article
Effect of Steering Wheel Vibration on drivers Hands in a Two-WheelDrivers Hand tractor

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The paper presents research results of the vibration transmitted from the steering wheel of the tractor with a 2-wheel drive to the driver’s hands. The vibration measurements were carried out on the tractor randomly chosen from the collage of agriculture / university of Baghdad. Before testing the tractor was examined and adjusted following the producer’s recommendations. The vibration levels were measured during the operation tillage at idling and at full load .The field was 31.7 m above level sea. Soil was treated at soil constant moisture (17-20 %) with depth of plowing (17 cm). During operation the weather temperature was measured (15 C) and humidity was ( 27 % ) The vibration level on the steering wheel was measured and analyzed .The frequency-weighted acceleration(RMS) , given in , was calculated. The vibration total value was defined as the root-mean-square of the three component value


Article
DESIGN, CONSTRUCTION AND TESTING OF LOW SPEED WIND TUNNEL WITH ITS MEASUREMENT AND INSPECTION DEVICES

Authors: Maki H. Majeed --- Ihsan Y. Hussain
Pages: 1550-1566
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A low speed open circuit wind tunnel has been designed, manufactured and constructed at the Mechanical Engineering Department at Baghdad University - College of Engineering. The work is one of the pioneer projects adapted by the R & D Office at the Iraqi MOHESR. The present paper describes the first part of the work; that is the design calculations, simulation and construction. It will be followed by a second part that describes testing and calibration of the tunnel. The proposed wind tunnel has a test section with cross sectional area of (0.7 x 0.7 m2) and length of (1.5 m). The maximum speed is about (70 m/s) with empty test section. The contraction ratio is (8.16). Three screens are used to minimize flow disturbances in the test section. The design philosophy is discussed and methods for wind tunnel calculation are outlined. Simulation of wind tunnel using ANSYS shows no separation of flow along wind tunnel. Construction steps are also included in present work


Article
The Effect of Shear on the Properties of Rigid PVC
تأثير قوى القص على خواص مادة متعدد (كلورايد الفاينيل) الصلب

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The rheological and fusion behavior of polyvinyl chloride (PVC) compounds plays a dominant role in the processing operations and in the development of physical properties in the processed material. A comprehensive study was made in this work to evaluate the effect of shear and thermal history on stability, mechanical and rheological properties of rigid PVC compounds. Different samples of Rigid Poly vinyl chloride including dry blend powder, granules, and bottles molded from both were examined. A study was also made on recycled RPVC where 25% of reclaimed material was continuously blended with fresh dry blend and processed for 15 cycles. Results showed that compaction of the PVC material took place in the brabender plastograph at constant temperature and shear stress. Correlations were given to explain results concerning residual stability and rheological behavior. Furthermore, it was seen that elongation and tensile impact are dependent on shear history


Article
EFFECT OF COOLING RATE ON MECHANICAL PROPERTIES OF EUTECTIC AND HYPOEUTECTIC Al-Si ALLOYS

Authors: Zeyad D. Kadhim
Pages: 1576-1583
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In this research the effect of cooling rate and mold type on mechanical properties of the eutectic and hypoeutectic (Al-Si) alloys has been studied. The alloys used in this research work were (Al- 12.6%Si alloy) and (Al- 7%Si alloy).The two alloys have been melted and poured in two types of molds with different cooling rates. One of them was a sand mold and the other was metal mold. Mechanical tests (hardness, tensile test and impact test) were carried out on the specimens. Also the metallographic examination was performed. It has been found that the values of hardness for the alloys(Al-12.6%Si and Al-7%Si) which poured in metal mold is greater than the values of hardness for the same alloy when it poured in a heated metal mold at different temperatures or in sand mold. The strength and impact resistance for the alloys (Al-12.6%Si and Al-7%Si) are greater when these were poured in a metal molds than that when it poured in a sand mold. Furthermore, the higher cooling rates enhance the strength, hardness and impact resistance for the two alloys, while the low cooling rates reduces these mechanical properties. The percentage of elongation and the amounts of formed porosity decreased when the cooling rates increased


Article
Image Reconstruction Using Modified Hybrid Transform

Authors: Ali K. Ibrahee --- Sulaiman Murtadha
Pages: 1584-1590
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In this paper, an algorithm for reconstruction of a completely lost blocks using Modified Hybrid Transform. The algorithms examined in this paper do not require a DC estimation method or interpolation. The reconstruction achieved using matrix manipulation based on Modified Hybrid transform. Also adopted in this paper smart matrix (Detection Matrix) to detect the missing blocks for the purpose of rebuilding it. We further asses the performance of the Modified Hybrid Transform in lost block reconstruction application. Also this paper discusses the effect of using multiwavelet and 3D Radon in lost block reconstruction


Article
OPTIMAL DESIGN OF MODERATE THICK LAMINATED COMPOSITE PLATES UNDER STATIC CONSTRAINTS USING REAL CODING GENETIC ALGORITHM

Authors: Musaddiq A. M. Kadem --- Majid H. Faidh-Allah
Pages: 1591-1599
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The objective of the current research is to find an optimum design of hybrid laminated moderate thick composite plates with static constraint. The stacking sequence and ply angle is required for optimization to achieve minimum deflection for hybrid laminated composite plates consist of glass and carbon long fibers reinforcements that impeded in epoxy matrix with known plates dimension and loading. The analysis of plate is by adopting the first-order shear deformation theory and using Navier's solution with Genetic Algorithm to approach the current objective. A program written with MATLAB to find best stacking sequence and ply angles that give minimum deflection, and the results comparing with ANSYS


Article
NUMERICAL INVESTIGATION OF NATURAL CONVECTION RADIATION AND MAGNETOHYDRODYNAMIC IN VERTICAL POROUS CYLINDRICAL CHANNEL
دراسة عددية للحمل الحر والإشعاع والمغناطيسية الهيدروديناميكية في قناة عمودية مملؤة بوسط مسامي

Authors: Hayder I. Mohammed --- Manal H. AL-Hafidh
Pages: 1600-1613
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A numerical study has been carried out to investigate heat transfer by natural convection and radiation under the effect of magnetohydrodynamic (MHD) for steady state axisymmetric two-dimensional laminar flow in a vertical cylindrical channel filled with saturated porous media. Heat is generated uniformly along the center of the channel with its vertical surface remain with cooled constant wall temperature and insulated horizontal top and bottom surfaces. The governing equations which used are continuity, momentum and energy equations which are transformed to dimensionless equations. The finite difference approach is used to obtain all the computational results using the MATLAB-7 programming. The parameters affected on the system are Rayleigh number ranging within (102 ≤Ra≤104), radiation parameter (0 ≤Rd≤2) and MHD (Mn) (0 ≤Mn≤2). The results obtained are presented graphically in the form of streamline and isotherm contour plots and the results show that heat transfer enhanced by radiation effect but decrease with the increase of magnetohydrodynamic. A correlation has been set up to give the average Nusselt number variation with Ra, Rd and Mn for which the results are found to be in good agreement with previously published researches which give maximum deviation of 3.73% when compared with the results of (Prasad, 1989).


Article
A GENERAL VELOCITY PROFILE FOR A LAMINAR BOUNDARY LAYER OVER FLAT PLATE WITH ZERO INCIDENCE

Authors: Qussai J. Abdul-Ghafour
Pages: 1614-1621
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A general velocity profile for a laminar flow over a flat plate with zero incidence is obtained by employing a new boundary condition to the other available boundary conditions. The general velocity profile is mathematically simple and nearest to the exact solution. Also other related values, boundary layer thickness, displacement thickness, momentum thickness and coefficient of friction are nearest to the exact solution compared with other corresponding values for other researchers


Article
THEORETICAL AND EXPERIMENTAL STUDY ON THERMAL PERFORMANCE OF CLOSED WET COOLING TOWER

Authors: Najim A. Jassim
Pages: 1622-1632
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Thermal performance of closed wet cooling tower has been investigated experimentally and theoretically in this work. The theoretical model based on heat and mass transfer equations and heat and mass transfer balance equations which are established for steady state case. A new small indirect cooling tower was used for conducting experiments. The cooling capacity of cooling tower is 1 kW for an inlet water temperature of 38oC, a water mass velocity 2.3 kg/m2.s and an air wet bulb temperature of 26oC. This study investigates the relationship between saturation efficiency, cooling capacity and coefficient of performance of closed wet cooling tower versus different operating parameters such wet-bulb temperature, variable air-spray water flow ratio and cooling water inlet temperature. Results indicate that the capacity and saturation efficiency was found close to the related experimental results. Good agreement was obtained between the theoretical results and experimental measurements for the performance of small cooling tower


Article
SIMULATION MODEL FOR THE ASSESSMENT OF DIRECT AND INDIRECT GEOREFERENCING TECHNIQUES IN ANALYTICAL PHOTOGRAMMETRY

Authors: B. Saleem --- H. Alwan --- L. Khalid
Pages: 1633-1642
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Abstract

This paper compares between the direct and indirect georeferencing techniques in Photogrammetry bases on a simulation model. A flight plan is designed which consists of three strips with nine overlapped images for each strip by a (Canon 500D) digital camera with a resolution of 15 Mega Pixels. The triangulation computations are carried out by using (ERDAS LPS) software, and the direct measurements are taken directly on the simulated model to substitute using GPS/INS in real case. Two computational tests have been implemented to evaluate the positional accuracy for the whole model and the Root Mean Square Error (RMSE) relating to (30) check points show that the indirect georeferencing is more accurate than the direct georeferencing. The computed RMSE of indirect georeferencing technique are (±0.0686 m., ± 0.0402 m.±, 0.3583 m.) in (X, Y, Z) respectively, while by direct georeferencing technique are (±0.1274 m., ± 0.1220 m., ± 0.5132 m.) in (X, Y, Z) respectively. Finally, the aim of this paper can be summarized as investigating the possibilities of using a simulation model to evaluate the applicability of direct and indirect georeferencing and analyzing the accuracy of both techniques


Article
Effect of Kerosene and Gasoline on Some Properties of High Performance Concrete

Authors: Dalia Shakir Atwan --- Nada Mahde Al-Jalawi
Pages: 1643-1657
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Abstract

During the last quarter century, many changes have taken place in the tanks industry and also in the materials that used in its production, while concrete is the most suitable material where concrete tanks has the benefits of strength, long service life and cost effectiveness. So, it is necessary improvement the conventional concrete in order to adapt the severe environment requirements and as a result high performance concrete (HPC) was used. It is not fundamentally different from the concrete used in the past, although it usually contains fly ash, ground granulated blast furnace slag and silica fume, as well as superplasticizer. So, the content of cementitious material is high and the water/cement ratio is low. In this study, the silica fume and superplasticizer were used for obtaining HPC. This paper is an attempt to provide some information about effect kerosene and gasoline on some properties of HPC which can be used as storage tanks for petroleum products. The experimental work in this research including; slump test, weight loss test and compressive strength test were performed. The results of these investigations indicated that the petroleum products have unacceptable effects on the properties of concrete

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