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:4

Article
التكامل البيئي- الاجتماعي - الجمالي في تصميم المجمعات السكنية لنمط متعدد الاسر - تقويم التجربة العراقية

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Abstract

The concept of (Environmental- social - aesthetical) integration is considered one of the most important concepts in any architectural design and any building, especially housing complexes The pattern of multi-family because of their importance at the present time due to the worsening housing crisis, and to reach out to the designs approaching a single family housing pattern, and that quite apart from what is happening now in our cities, where the designs of housing complexes have been taken from the formal imitation ,a curriculum, and ready technological solutions an easy way, that drifted it away from its special identity, and led to the neglect of information, data and solutions and expertise accumulated over many years, in the Arab heritage of the traditional residential district, and on this basis the problem of research based on the "lack of inclusive knowledge and the scarcity of specialized studies of (Environmental – social - aesthetical) integration in designing housing complexes The pattern of multi-family ", as most previous studies, specializing in one of these elements and neglected or passed by unnoticed the others and there have not taking into account the fact that the designing process needs the integration of all these elements to get to a design belongs to the environment and fulfill the needs of residents and reflects them. The strategic objective of this research is to demonstrate the importance of the concept of integration of(Environmental – social - aesthetical)aspects in designing housing complexes The pattern of multi-family (through the global experience and local) and branches of this strategic objective, several sub-goals: 1 - Explain the most important items of( environmental, social, aesthetical) values of the traditional residential district and put it in contemporary form. 2 - After knowing the most important active vocabulary for each aspect of the values and put it in contemporary form we will use it as a measurement to evaluate the Iraqi experience . ReSearch took from the traditional residential district a material for study and analysis to reach the main advantages and features of the environment for use in our contemporary designs not by formal imitation, but we must go to a deeper level to the thought associated with this traditional environment and try to simulate the characteristics of thought, which produced such architecture in our quest towards a design style housing complexes to multi-families reflect this heritage and continuing with it and fulfill the needs of residents and ensure the necessary integration among the( environmental- social - aesthetical) aspects, within the developments of our time and harness of techniques and technology, within the framework of thought integral.

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Article
Study the Role of Novolak Composite in Repress of light Charged Particles and Make it Neutral
دراسة دور متراكبات النوفولاك في ولوج الجسيمات المشحونة الخفيفة وجعلها عديمة التأثير

Authors: رولا عبد الخضر عباس
Pages: 177-191
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Abstract

It is well known, that each benefit can be derived for the rights of the use of ionizing radiation or exposure to be held in the light of the damage caused by the human race, which pays to take a negative attitude of all nuclear applications and even peaceful, he can study the results of extensive nuclear testing to minimize the damage to tie with damage resulting from any process of technological or other industry. There are many of the party for control of external exposure to radiation and reduction of the minimum particularly the method of packaging or armor because it actually levels the Secretary to meet the requirement to contain the permissible limits of pollutants. This has been in the study and enter the light charged particles (beta) emitted by the radioactive source (90Y / 90Sr) in the protective barriers are made of different phenolic composite material consisting of advanced developer novolak factors improve the quality and short glass fiber reinforced (fiber Short) time and fiber asbestos (fiber Asbestos) again. The possible use of hybrid composite materials in curbing such ionizing radiation consisting of reinforced material novolak (30% glass fiber + 30% asbestos fiber) in addition to the preparation of polymeric complexes of other Epoxy reinforced glass fiber in order to short the comparison with complexes novolak to achieve a higher extent safety of these packages, please curb beta minutes to become neutral. Note that all materials prepared overlapped supported the strengthening of materials fracture and weight (60%). In general, is on the decline in the intensity of light when the particles penetrate the target in the subject to read the prepared reagent detector in the light of the results obtained can be measured both types of linear attenuation coefficients and mass taking into account the measurement of largest thickness of material processed can be for a few particle a house that you walk into it (XB) and appointment of (XB) measured R(Rang) particle in the prepared composite. And that these measurements are the most appropriate metrics that can be used to estimate the efficiency of materials prepared for beta particles attenuation. I have discerned from the results that Epoxy with braking radiation on the viability of particulate matter under study than it is in the article novolak reference to the low value (XB) in epoxy is accompanied by lower beta particles range also asked in the article novolak The situation is generally low when you consolidate these materials, glass fiber, causing a significant increase in linear attenuation coefficients and mass. Since the most important characteristic of the epoxy material novolak usability of high thermal endurance, which helps to improve the characteristics of protective packaging manufacturer, including and especially composite Reinforced and the role of the most important and greater than in the case of epoxy despite its superiority in the process of attenuation. As evidenced by the results of this study that supported novolak composite Reinforced asbestos fibers causing a decrease in the thickness of the layer braking particles beta significantly and, therefore, the manufacturer of protective packaging machinery, consisting of hybridization novolak article, which includes asbestos, glass fibers with each other at the same time help the emergence of properties unique. And, finally, to increase the focus (HMTA) between (10% - 14%) - the concept of organic chemicals industry - means that the intensity of cross link density, which causes high efficiency of the process of attenuation of these materials.

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Article
اختيار مواقع لإنشاء سدود صغيرة في منخفض الكعرة باستخدام تقنيات التحسس النائي والتحليل المكاني

Authors: Dalal J. Ali --- Hussain Z. Ali
Pages: 192-211
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Abstract

Feature extraction from the surface topography is the creation of a bitmap representing the earth's surface elevations based on Digital Elevation Model, which is the base of the analyzing of topographical surfaces. The digital elevation models are mainly derived by stereo pair images (a pair of images) available from the Photogrammetry data and remote sensing, or from topographical maps, and we use a digital elevation model derived from topographical maps, and we derived a number of important properties from digital elevations model such as gradient direction and the Earth's shadow using a ArcGIS ver. 9.3 , which represent the input data to extract the hydrological characteristics such as determining the flow direction , also calculating the flow accumulation , producing the output map Stream to determine the valleys in the region and the production of Basin map to determine the basin of nutrition , the locations of the small dams can be selected using Arc GIS ver. 9.3 and its extension Arc Hydro.


Article
Natural Convection Heat Transfer In an Inclined Circular Cylinder

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Abstract

Experiments were carried out to investigate natural convection heat transfer in an inclined uniformly heated circular cylinder . The effects of surface heat flux and angle of inclination on the temperature and local Nusselt number variations along the cylinder surface are discussed . The investigation covers heat flux range from 92 W/m² to 487 W/m², and angles of inclination 0° ( horizontal) , 30° , 60° and 90° (vertical) . Results show an increase in the natural convection as heat flux increases and as angle of inclination moves from vertical to horizontal position. An empirical equation of average Nusselt number as a function of Rayliegh number was deduced for each angle of inclination.


Article
Experimental Investigation of Laminar Natural Convection Heat Transfer in a Rectangular Enclosure with and without Inside Partitions

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Abstract

Experimental study has been conducted for laminar natural convection heat transfer of air flow through a rectangular enclosure fitted with vertical partition. The partition was oriented parallel to the two vertical isothermal walls with different temperatures, while all the other surfaces of the enclosure were insulated. In this study a test rig has been designed and constructed to allow studying the effect of Rayleigh number, aperture height ratio, partition thickness, the position of aperture according to the side walls and according to the height, the position of the partition according to the hot wall, and partition inclination. The experiments were carried out with air as the working fluid for Rayleigh number range (5*10^7 – 1.3*10^8) and aspect ratio of (0.5). 22 different configurations of partition were used in this study these are: a) Undivided enclosure (no – partition). b) (21) Cork partitions of different shapes. Empirical correlations for average Nusselt number are obtained for the different cases tested. The results show that heat transfer is independent on the partition position according to the cold wall and according to the upper or lower walls, while it shows that heat transfer is sensitive to: 1. Rayleigh number (Ra), which increase with increasing Ra. 2. Aperture height ratio (Ap=hp/H), which is found that when Ap= 5/6 (case 2,3), the reduction in heat transfer is 10.3%, while when Ap=1/2 (case 4,5), the reduction is 17.2% compared with the non partitioned enclosure. 3. Aperture position according to the height, which is found that when the aperture at the centre of the partition (case 13), the reduction in heat transfer is 16.7%, while when the aperture displaced to the upper surface (case 14), the reduction is 19% compared with the non partitioned enclosure. 4. Partition thickness (t), which is found that when t = 10 mm (case 4,5) the reduction in heat transfer is 17.2%, while when t = 150 mm (case 16) the reduction is 20.5% compared with the non partitioned enclosure. 5. Partition inclination (δ), which is found that the rate of heat transfer reduced with increasing as shown: a. For δ= 30° toward the cold wall (case 22), the reduction in heat transfer is 18.2%. b. For δ= 45° toward the cold wall (case 18), the reduction in heat transfer was 21.9%. c. For δ= 60° toward the cold wall (case 20), the reduction in heat transfer is 30.2%. d. For δ= 30° toward the hot wall (case 21), the reduction in heat transfer is 31.3%. e. For δ= 45° toward the hot wall (case 17), the reduction in heat transfer is 40.7%. f. For δ= 60° toward the hot wall (case 19), the reduction in heat transfer is 42.1%


Article
Investigation of Twisted Tape Turbulator for Fire Tube Boiler

Authors: Rashid K. Insayif --- Karima E. Amori
Pages: 694-713
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The present work presents a new experimental study of the enhancement of turbulent convection heat transfer inside tubes for combined thermal and hydrodynamic entry length of one popular “turbulator” (twisted tape with width slightly less than internal tube diameter) inserted for fire tube boilers. Cylindrical combustion chamber was used to burn (1.6 to 7kg/h) fuel oil #2 to deliver hot gases with ranges of Reynolds number (10500 to 21700), and (11400 to 24150) for both empty and inserted tube respectively.A uniform wall temperature technique was used by keeping approximately constant water temperature difference (25ºC) between inlet and exit cooling water in parallel flow shell and tube heat exchanger. The test tube consisted of smooth carbon steel tube of (2400mm) long and (52mm) internal diameter. This test tube instrumented to derive local heat transfer coefficient and local flue gasses static pressure.The experimental results show that for the same fuel consumption, twisted tape insert with (H/D = 11.15) enhanced the mean Nusselt number in (75.2%), (68.8%), (49.8%), (40.3%), and (16.7%) for fuel consumption (7kg/h), (6.16kg/h), (4.5kg/h), (3.24kg/h), and (1.6kg/h) respectively.A set of empirical correlations that permit the evaluation of the mean Nusselt number (for developing and fully developed region), and average Nusselt number (for developed region) for empty and inserted tube are generated for engineering applications.


Article
Numerical Investigation of Laminar Mixed Convection in Trombe Wall Channel

Authors: Yasser A. Abd --- Saad M. Saleh
Pages: 714-728
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The two dimensional steady, combined forced and natural convection in vertical channel is investigated for laminar regime. To simulate the Trombe wall channel geometry properly, horizontal inlet and exit segments have been added to the vertical channel. The vertical walls of the channel are maintained at constant but different temperature while horizontal walls are insulated. A finite difference method using up-wind differencing for the nonlinear convective terms, and central differencing for the second order derivatives, is employed to solve the governing differential equations for the mass, momentum, and energy balances. The solution is obtained for stream function, vorticity and temperature as dependent variables by iterative technique known as successive substitution with overrelaxation. The flow and temperature patterns in the channel are obtained for Reynolds numbers and Grashof number ranging from 25 to 100 and (100 to 1,000,00,) respectively. A computer program ( Fortran 90 ) is built to calculate the fraction factor and the total average Nusselt number (Nu) also the average heat transfer Q in steady state and for Aspect ratio Ar (10) and Grashof number GR (10^2 - 10^5 ), the fluid Prandtl number is fixed at (Pr=0.733) and Reynolds number Re (25-100). The results show reasonable representation to the relation between Nusselt number and friction factor with other parameters (Ar, GR and Re). Nu is increased with increasing Re and GR but it decreases with Ar increase and (Q) is increased with increasing Re ,GR and Ar. At the same time, the product friction factor(fRe) increased with (GR) and (Ar)increased and (Re )decrease. Comparison of the result with the previous work shows a good agreement.


Article
Effect of the Sand Mould Additives on Some Mechanical Properties of Carbon Steel Ck45 Casts

Authors: Khairia Salman Hassan --- Hani Aziz Ameen
Pages: 729-739
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Abstract

The research targets study of influence of additives on sand mold’s properties and, consequently, on that of carbon steel CK45 casts produced by three molds. Three materials were selected for addition to sand mix at weight percentages. These are sodium carbonates, glycerin and oat flour. Sand molds of studied properties were produced to get casts from such molds. The required tests were made to find the best additives with respect to properties of cast. ANSYS software is used to demonstrate the stresses distribution of each produced materials. It is shown that the mechanical properties of casts produced is improved highly with sodium carbonates and is less with oat flour and it is seem a few with glycerin additives. It can be concluded that the sodium carbonates let to get the cast produced with highly mechanical properties.


Article
Preservation of Required Chlorine Concentration in Baghdad Water Supply Networks using on-Site Chlorine Injection

Authors: Riadh Fadhil Al-Azzawe --- Rafa H. Al-Suhaili
Pages: 740-762
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Abstract

The chlorine concentration variation in Baghdad water networks was studied. The chlorine data were collected from Mayoralty of Baghdad and Ministry of Environment (MOE) for the networks for both sides of the city Karkh and Rasafa for (2008-2009). The study of these data indicates that there are no systematic testing program .Classified GIS maps showed that the areas far from the treatment plants have almost always low chlorine concentration .This indicates that the problem of the low chlorine concentration in the far areas is due to cracks of pipe along the conveyance path ,as expected. The area's most frequently have low concentration are Al-sadir,Al-Kadhimya, and Al-Amiria . It was found also that the chlorine concentrations were lowest in summer months than those in winter months.The Amiria area district (636) was selected as a case study to test the ability of using the quantitative- qualitative model in the EPANET software, to find the required onsite chlorine injection point number, locations and dose, so as to raise the chlorine concentration to the acceptable limits in the other nodes of the network. The bulk decay coefficient was found to be (-2.212)1/day and the wall coefficients were found to be between (-0.001)to(-0.9)1/day The main conclusion of this study is that the onsite injection can improve the chlorine concentration in Baghdad water supply networks. The EPANET model can be used effectively to obtain the required injection program for this purpose.

Keywords

Water --- Supply --- Network --- EPANET --- Geographical --- Information --- System --- Sectoral --- Chlorine --- Injection


Article
Numerical Investigation of Static and Dynamic Stresses in Spur Gear Made of Composite Material

Authors: THAR M. BADRI --- MOHAMMAD Q. ABDULLAH
Pages: 763-782
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In this current work, Purpose; to clearly the fundamental idea for constructing a design and investigation of spur gear made of composite material its comes from the combination of (high speeds, low noise, oil-les running, light weight, high strength, and more load capability) encountered in modern engineering applications of the gear drives, when the usual metallic gear cannot too overwhelming these combinations. An analyzing of stresses and deformation under static and dynamic loading for spur gear tooth by finite element method with isoparametric eight-nodded in total of 200 brick element with 340 nods in three degree of freedom per node was selected for this analysis. This is responsible for the catastropic failure studying of spur gear made of composite material. Also obtain the natural frequencies and the mode shape of the composite tooth under (concentrated and or moving on surface profile) load of one half sinusoidal type impulse for two types of composite materials (Glasses/Epoxy & Graphite/Epoxy) and they are compared with the mild steel gear values. The appearances that improve the successfully of composite gear in the weight, stiffness, load capability, and dynamic behavior respect to the mild steel, which is found that composite materials may also be thought of as a material for power transmission gearing, from a stress point of view.


Article
Rheological Properties of Iraqi Asphalt Binders Measured Using Superpave System and Shell Software

Authors: Namir G. Ahmed --- Hamed M. Hamdou --- Alaa H. Abed
Pages: 783-799
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The performance grading system (superpave) has provided means to incorporate binder characteristics with pavement failure types. It’s a comprehensive system that relates climate, traffic conditions and aging with critical pavement distress. The objective of this paper is to develop an improved asphalt binder grading system for Iraq based on the principal of superpave. The country was divided into different zones according to the highest and lowest temperature ranges and traffic loading. The Performance graded binder proposed for each zone was compared with some States of USA that have same hot weather of Iraq by using Long Term Pavement Performance (LTPP v3.1) software. Iraqi asphalt samples were tested using the Superpave technology in Wisconsin University and the results were compared with those estimated using Shell pavement design software packages (BANDS 2) at different loading time and frequency. In general, the performance grade of binders produced from the three refineries in Iraq (Daurah, Basrah and Baiji) is PG 64-16. The m- value (slope of log creep stiffness versus log frequency curve at specified temperature) determined by DSR (Dynamic Shear Rheometer) and Shell software was compared.


Article
Dye Removal from Textile Wastewater by Coagulation Using Alum and PAC
ازالـة الالوان من الماء المطروح في الصناعـات النسيجيـة بالتخثيـر بواسطـة الشـب ومتعدد كلوريد الالمنيـوم

Authors: Nada N. Abdul-Razzaq
Pages: 800-806
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Removal of solar brown and direct black dyes by coagulation with two aluminum based coagulants was conducted. The main objective is to examine the efficiency of these coagulants in the treatment of dye polluted water discharged from Al-Kadhymia Textile Company (Baghdad-Iraq). The performance of these coagulants was investigated through jar test by comparing dye percent removal at different wastewater pH, coagulant dose, and initial dye concentration. Results show that alum works better than PAC under acidic media (5-6) and PAC works better under basic media (7-8) in the removal of both solar brown and direct black dyes. Higher doses of PAC were required to achieve the maximum removal efficiency under optimum pH conditions for both dyes. It was observed that under optimum conditions of pH and dose values, PAC was significantly higher dye removal efficiency than alum for all dyes initial concentrations.


Article
Experimental Observations on the Behavior of a Piled Raft Foundation
مشاهدات عملية على تصرف الأساس الحصيري المستند الى ركائز

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The piled raft is a geotechnical composite construction consisting of three elements: piles, raft and soil. In the design of piled rafts, the load shared between the piles and the raft, and the piles are used up to a load level that can be of the same order of magnitude as the bearing capacity of a comparable single pile or even greater. Therefore, the piled raft foundation allows reduction of settlements in a very economic way as compared to traditional foundation concepts. This paper presents experimental study to investigate the behavior of piled raft system in sandy soil. A small scale “prototype” model was tested in a sand box with load applied to the system through a compression machine. The settlement was measured at the center of the raft, strain gages were used to measure the strains and calculate the total load carried by piles. Four configurations of piles (2x1, 3x1, 2x2 and 3x2) were tested in the laboratory, in addition to rafts with different sizes. The effects of pile length, pile diameter, and raft thickness on the load carrying capacity of the piled raft system are included in the load-settlement presentation. It was found that the percentage of the load carried by piles to the total applied load of the groups (2x1, 3x1, 2x2, 3x2) with raft thickness of 5 mm, pile diameter of 9 mm, and pile length of 200 mm was 28% , 38% , 56% , 79% , respectively. The percent of the load carried by piles increases with the increase of number of piles.

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Article
Reliability Analysis of the Seismic Stability of Embankments Reinforced with Stone Columns
الاعتمادية في تحليل الاستقرارية تحت تاثير الهزات الارضية للسداد الترابية المسلحة بالاعمدة الحجرية

Authors: Ahmed S. Jawad
Pages: 829-845
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Geotechnical engineers have always been concerned with the stabilization of slopes. For this purpose, various methods such as retaining walls, piles, and geosynthetics may be used to increase the safety factor of slopes prone to failure. The application of stone columns may also be another potential alternative for slope stabilization. Such columns have normally been used for cohesive soil improvement. Most slope analysis and design is based on deterministic approach i.e a set of single valued design parameter are adopted and a set of single valued factor of safety (FOS) is determined. Usually the FOS is selected in view of the understanding and knowledge of the material parameters, the problem geometry, the method of analysis and the consequences of failure. This results in different FOS obtained by different designers. This inherent variability characteristic dictates that slope stability problem is a probabilistic problem rather than deterministic problem. Furthermore, the FOS approach cannot quantify the probability of failure or level of risk associated with a particular design situation. The objective of this study is to integrate probabilistic approach as a rational means to incorporate uncertainty in the slope stability analysis. The study was made through a hypothetical problem which includes a sensitivity analysis. The methodology is based on Monte Carlo simulation integrated in commercially available computer program SLOPE/W. The output of the analysis is presented as the probability of failure as a measure of the likelihood of the slope failure. Results of this study have verified that the probability of failure is a better measure of slope stability as compared to the factor of safety because it provides a range of value rather than a single value.


Article
Effect of Steel Fibers Addition on the Behavior of High Strength Concrete Circular Short Columns
تأثير إضافة ألياف الفولاذ على سلوك الأعمدة الخرسانية الدائرية عالية المقاومة و القصيرة

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This paper presents the effects of the addition of steel fibers on the behavior of concentrically loaded reinforced concrete circular short columns. An experimental investigation into the behavior of 24 short reinforced concrete columns with and without steel fibers was carried out. The columns had a circular section (200 mm diameter and 900 mm long). Test variables include concrete strength, spacing of spiral reinforcement, and inclusion of steel fibers. The axial stress and axial strains were obtained and used to evaluate the effects of the presence of steel fibers. It was found that the addition of steel fibers slightly improves the load carrying capacity of the tested columns whereas it significantly enhances the ductility of these specimens. Test results also indicated that for the same confinement parameter psfsy/f'c , specimens with steel fibers has higher strength enhancement compared to specimens without steel fibers. For confinement parameter of 0.1 the strength enhancement equal 1.7 for specimens with fibers while it is 1.4 for nonfibrous specimens. An empirical expression is proposed and used to predict the confined strength of columns. It was shown that the proposed formula predicts the load carrying capacity of the tested columns reasonably.


Article
Design Of A Continuous Sliding Mode Controller For The Electronic Throttle Valve System

Authors: Shibly Ahmed AL-Samarraie
Pages: 859-871
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Lowering the emission, fuel economy and torque management are the essential requirements in the recent development in the automobile industry. The main engine control input that satisfies the above requirements is the throttling angle which adjusts the air mass flow rate to the engine port. Due to the uncertainty and the presence of the nonlinear components in its dynamical model, the sliding mode control theory is utilized in this work for the throttle valve angle control system to design a robust controller for this system in the presence of a nonlinear spring and Coulomb friction. A continuous sliding mode control law which consists of a saturation function, instead of a signum function, and the integral of another saturation function is used in this work. This choice for the control structure will prevent the chattering to occurs but with a certain steady state error. On the other hand, the addition of the integral term will effectively reduce the steady state error according to the choice of its parameters. The simulations result for typical references of the opening throttle angle demonstrate the effectiveness of the proposed controller, especially after the addition of a nonlinear integral term.


Article
Exhaust Analysis and Performance of a Single Cylinder Diesel Engine Run on Dual Fuels Mode
تحليل أداء وملوثات محرك ديزل أحادي الاسطوانة يعمل بنظام وقود ثنائي

Authors: Miqdam Tariq Chaichan
Pages: 873-885
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Generally fossil based fuels are used in internal combustion engines as an energy source. Excessive use of fossil based fuels diminishes present reserves and increases the air pollution in urban areas. This enhances the importance of the effective use of present reserves and/or to develop new alternative fuels, which are environment friendly. Use of alternative fuel is a way of emission control. The term “Alternative Gaseous Fuels” relates to a wide range of fuels that are in the gaseous state at ambient conditions, whether when used on their own or as components of mixtures with other fuels. In this study, a single cylinder diesel engine was modified to use LPG in dual fuel mode to study the performance, emission, and combustion characteristics. The primary fuel, liquefied petroleum gas (LPG), was mixed with air, compressed, and ignited by a small pilot spray of diesel. Dual fuel engine showed a reduction in oxides of nitrogen in the entire load range. The brake thermal efficiency improved by 3% in dual fuel mode, especially at low load, and also reduced the hydrocarbon, carbon monoxide, and CO2 emissions.


Article
Photo Dynamic Therapy (PDT) with Biological Tissues using Nd:Glass Laser

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A Photo Dynamic Therapy (PDT) is a technique which is used with Laser to treat many of cancer tissues. This paper deals with the relatively new therapeutic technique (PDT) with pulsed Nd:glass Laser which was applied to human soft tissues (Ovary and Kidney tissues), and to the hard tissues (freshly extracted human teeth), with power density of 280 watt/mm2 and exposure time 330 usec. Different dyes (Blue, methylene, eosin, and orange) were applied to the area before irradiation to study the effect of the pigments on the laser interaction with biological tissues. The zone of treatment (Z-necrosis) with aid of MATLAB was determined. The relationship of zone of treatment with exposure time, accumulated damage and fraction of oxidative radicals was obtained.


Article
Dissolution Of Benzene In The Saturated Porous Media

Authors: Hatem Asal Gzar --- Abbas H. Sulaymon
Pages: 898-911
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The aim of the present research is to study the dissolution and transport process of benzene as a light nonaqueous phase liquid (LNAPL) in saturated porous media. Unidirectional flow at water velocities ranged from 0.90 to 3.60 cm/hr was adopted to study this process in a three dimensional saturated sand tank (100 cm×40 cm×35 cm). This tank represents a laboratory-scale aquifer. The aquifer was constructed by packing homogeneous sand in the rectangular tank. The experimental results were used to characterize the dissolution behavior of an entrapped nonaqueous phase benzene source in a three dimensional aquifer model. The time invariant average mass transfer coefficient was determined at each interstitial velocity, the values of this coefficient were ranged from 0.016 to 0.061 cm/hr. It was increased proportionally with velocity toward a limiting value. The results show that the concentration of the LNAPL reduces as the distance increased in x and/or z direction from the source of pollution. In most cases the benzene concentration declines with velocity more than 2.34 cm/hr at downstream of the LNAPL pool.


Article
Forward and Reverse Osmosis Process for Recovery and Re-use of Water from Polluted Water by Phenol
عملية التناضح الامامي والعكسي لاسترجاع واعادة استخدام الماء من المياه الملوثة بالفينول

Authors: Ahmed Faiq Al-Alawy
Pages: 912-928
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The research aims to apply the novel forward osmosis (FO) process to recover pure water from contaminated water. Phenol was used as organic substance in the feed solution, while sodium chloride salt was used as draw solution. Membranes used in the FO process is the cellulose triacetate (CTA) and polyamide (thin film composite (TFC)) membrane. Reverse osmosis process was used to treatment the draw solution, the exterior from the forward osmosis process. In the FO process the active layer of the membrane faces the feed solution and the porous support layer faces the draw solution and this will show the effect of dilutive internal concentration polarization and concentrative external concentration polarization. In the FO process was a run-time for five hours, and the concentration of phenol 100 and 1000 mg/l, and for the NaCl the concentration was 10000 and 30000 mg/l. It was found that recovery percent increases with increasing time, while water flux through membrane decreases with increasing time. Also, it was found that recovery and water flux increases with increasing draw solution concentration, on the contrary, water flux and the percentage of recovery decreases with increasing the concentration of phenol (feed solution). Increase in draw solute (NaCl) concentration has more effect on the water flux in FO process compared with increase in the concentration of phenol. Outlet phenol concentration increases with time, while the outlet salt concentration decreases with increasing the time. The results showed that the cellulose triacetate membrane gave the highest recovery ratio from the thin film composite membrane. The highest recovery was reached in five hours is 51.33%, while using CTA membrane recovery rate increase, by 23% compared with TFC membrane. The value of the resistance to solute diffusion within the membrane porous support layer is 36.83 h/m. Reverse osmosis is perfect method for removal of dissolved salts from water, thus its suitable process for reducing the content of NaCl in draw solution; therefore the sodium chloride rejection percentage was 91.6 – 96 % for polyamide membrane (TFC). Within two hours of work of the reverse osmosis system the recovery percentage of pure water is 58%.


Article
Optimization Of Resource Allocation And Leveling Using Genetic Algorithms

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Abstract

Resource allocation and leveling are of the top challenges in project management, due to the complexity of projects. This research aims to develop an optimization model for resource smoothing, so that. The proposed model is formulated using C++ program for resource smoothing. The project management software MS-Projects is adopted hereto perform resource leveling to facilitate achieving the optimal solution. The proposed model utilizes a system that depends on Genetic Algorithms (GAs) procedure built in C++ program to find the optimum solution. This research reach concludes that it is possible to smooth resources using Genetic Algorithms program and compares then with MS-Project when the GA results are better than MS-Project. Three case studies have been applied in this research and the application results come identical with research objectives, to form the conclusion. Then comes the recommendations regarding adopting and using the research results in construction planning and project management. Further suggestions related to the research subject are proposed for future works.

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Article
Damage Detection And Location For In And Out-Of- Plane Curved Beams Using Fuzzy Logic Based On Frequency Difference

Authors: Hayder S. Ashoor --- Nabil H. Hadi
Pages: 948-966
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Abstract

In this study, structures damage identification method based on changes in the dynamic characteristics (frequencies) of the structure are examined, stiffness as well as mass matrices of the curved (in and out-of-plane vibration) beam elements is formulated using Hamilton's principle. Each node of both of them possesses seven degrees of freedom including the warping degree of freedom. The curved beam element had been derived based on the Kang and Yoo’s thin-walled curved beam theory in 1994. A computer program was developing to carry out free vibration analyses of the curved beam as well as straight beam. Comparing with the frequencies for other researchers using the general purpose program MATLAB. Fuzzy logic system (FLS) applied in two stages to calculate the damage extent and location in simply in and out-of- plane curved beam, the damage deduce by reduction in stiffness for three levels (20%, 40%, 60%). At the first stage the output faults of the fuzzy system represented by four levels of damage in curved beam (undamaged, slight, moderate, and severe), and at second stage indicate damage location at element with two defuzzification me-thods (centroid and middle of maximum). The results show that the frequency difference method is efficient to indicate and quantify damage with accuracy about (99.5%) for slight and moderate damage about (100%) for severe damage. Consequently fuzzy logic performs well for detecting, locating and quantifying damage in curved beam.


Article
Implementation of Root Finding Algorithm of Minimum Phase Filter Using VHDL

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Abstract

Root-finding is an oldest classical problem, which is still an important research topic, due to its impact on computational algebra and geometry. In communications systems, when the impulse response of the channel is minimum phase the state of equalization algorithm is reduced and the spectral efficiency will improved. To make the channel impulse response minimum phase the prefilter which is called minimum phase filter is used, the adaptation of the minimum phase filter need root finding algorithm. In this paper, the VHDL implementation of the root finding algorithm introduced by Clark and Hau is introduced. VHDL program is used in the work, to find the roots of two channels and make them minimum phase, the obtained output results are similar in accuracy to the past work results, which is built by using MATLAB program. Using VHDL is necessary in FPGAs for building hardware of the root finding algorithm in lower cost and time. MATLAB program is used only for displaying the input and output discrete signals of tested channels.

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Article
Experimental Study Of Air Flow Rate Effects On Humidification Parameters With Preheating And Dehumidification Process Changing

Authors: Ayad Tareq Mustafa
Pages: 979-992
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Abstract

This research study experimentally the effect of air flow rate on humidification process parameters. Experimental data are obtained from air conditioning study unit T110D. Results obtained from experimental test, calculations and psychometrics software are discussed. The effect of air flow rate on steam humidification process parameters as a part of air-conditioning processes can be explained according to obtained results. Results of the steam humidification processes (1,2) with and without preheating with 5A and 7.5A shows decreasing in dry bulb temperature, humidity ratio, and heat add to moist air with increasing air flow rate, but humidification load, and total energy of moist air increase with increasing air flow rate in the testing tunnel. The steam humidification process (1) with dehumidifying coil shows increase in dry bulb temperature, humidity ratio, humidification load, and heat add to moist air with increasing air flow rate in the testing tunnel, but the total energy decrease as air flow rate increase. These obtained results can be beneficial for controlling comfort air-conditioning processes in buildings.


Article
Correlations of Point Load Index and Pulse Velocity with the Uniaxial Compressive strength for rocks

Authors: Muhammad Abdul Jabbar
Pages: 992-1006
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Abstract

Rock engineers widely use the uniaxial compressive strength (UCS) of rocks in designing surface and underground structures. The procedure for measuring this rock strength has been standardized by both the International Society for Rock Mechanics (ISRM) and American Society for Testing and Materials (ASTM), Akram and Bakar(2007). In this paper, an experimental study was performed to correlate of Point Load Index ( Is(50)) and Pulse Wave Velocity (Vp) to the Unconfined Compressive Strength (UCS) of Rocks. The effect of several parameters was studied. Point load test, Unconfined Compressive Strength (UCS) and Pulse Wave Velocity (Vp) were used for testing several rock samples with different diameters. The predicted empirical correlations based on various test results indicate that the UCS could be obtained directly from measured (Vp), and then the Index Is(50) can be calculated by back substitution.


Article
Preparation of Activated Carbons from Date Stones by Chemical Activation Method Using Fecl3 and Zncl2 as Activating Agents

Authors: Muthanna J. Ahmed
Pages: 1007-1022
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Abstract

Date stones were used as precursor for the preparation of activated carbons by chemical activation with ferric chloride and zinc chloride. The effects of operating conditions represented by the activation time, activation temperature, and impregnation ratio on the yield and adsorption capacity towards methylene blue (MB) of prepared activated carbon by ferric chloride activation (FAC) and zinc chloride activation (ZAC) were studied. For FAC, an optimum conditions of 1.25 h activation time, 700 ˚C activation temperature, and 1.5 impregnation ratio gave 185.15 mg/g MB uptake and 47.08 % yield, while for ZAC, 240.77 mg/g MB uptake and 40.46 % yield were obtained at the optimum conditions of 1.25 h activation time, 500 ˚C activation temperature, and 2 impregnation ratio. The equilibrium data for MB adsorption on prepared activated carbons at optimum conditions were well represented by the Langmuir isotherm model, giving maximum MB uptake of 304.51 and 387.54 mg/g for FAC and ZAC, respectively. Also, the results showed that the surface area and iodine number of activated carbon prepared by activation with ferric chloride at optimum conditions were 780.06 m2/g and 761.40 mg/g, respectively. While 1045.61 m2/g surface area and 1008.86 mg/g iodine number were obtained for ZAC prepared at optimum conditions.


Article
Properties Of Hardened Concrete Using Crushed Clay Brick As Aggregates
خصائص الخرسانة المتصلبة باستخدام مكسر الطابوق الطيني

Authors: Osama M. Ghazi
Pages: 1022-1038
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Abstract

This paper provides the result of an investigation to use of crushed clay brick as aggregates in producing concrete. Eight different crushed clay brick aggregate concretes were used in this investigation. Compressive strength, splitting tensile strength and pulse velocity of crushed clay brick aggregates concrete were determined and compare to natural aggregate concrete. The compressive strength of crushed clay brick aggregates concretes were always lower than the compressive strength of natural aggregates concrete regardless the age of concrete, but the crushed clay brick aggregates concrete showed better performance as the age of concrete increases and average reduction in compressive strength were 33.5% at the age of 7 days but it becomes only 20% at the age of 56 days compared to natural aggregates concrete. The splitting tensile strength of crushed clay brick aggregates concrete were always lower than natural aggregate concrete, the reduction in splitting tensile strength of crushed clay brick aggregates concrete is ranging between 11 and 26% with an average reduction of about 18.5% compared to natural aggregates concrete. The pulse velocity of crushed clay brick aggregates concrete were also lower than natural aggregates concrete, the reduction in pulse velocity of crashed clay brick aggregates concrete is ranging between 6 and 22% with an average reduction of about 14% compared to natural aggregates concrete.


Article
LDPC Coded Multiuser MC-CDMA Performance Overmultipath Rayleigh Fading Channel
منظومة (LDPC-MCCDMA) متعدد المستخدمين

Authors: Aqiel N. Almaamory
Pages: 1039-1046
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Abstract

This work presents the simulation of a Low density Parity Check (LDPC) coding scheme with multiuserMulti-Carrier Code Division Multiple Access (MC-CDMA) system over Additive White Gaussian Noise (AWGN) channel and multipath fading channels. The decoding technique used in the simulation was iterative decoding since it gives maximum efficiency with ten iterations. Modulation schemes that used are Phase Shift Keying (BPSK, QPSK and 16 PSK), along with the Orthogonal Frequency Division Multiplexing (OFDM). A 12 pilot carrier were used in the estimator to compensate channel effect. The channel model used is Long Term Evolution (LTE) channel with Technical Specification TS 25.101v2.10 and 5 MHz bandwidth including the channels of indoor to outdoor/ pedestrian channel and Vehicular channel.

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