Journal of Engineering

1

معامل الفعالية البوزولانية للفلدسبار المحلي

Zainab A. Alkaissi, Duraid A. Al Khafagy

Pages: 633-643 English

Abstract

This study investigates the pozzolanic activity of local fly ash and compares it with imported silica fume. The fly ash was ground to a fineness of 1200 m²/kg using a Blaine air permeability apparatus. The pozzolanic activity was evaluated according to ASTM C311 standards. The results showed that the pozzolanic activity of the local fly ash was 97%, compared to 92% for the silica fume. This indicates the potential of using locally available fly ash as an active pozzolanic material in high-performance concrete and high-strength concrete mix designs.

Keywords

Pozzolanic Activity Local Fly Ash Silica Fume Cementitious Materials Concrete Mix Design Compressive Strength Blaine Fineness ASTM Standards

2

لأصالة والمعاصرة في المسكن الريفي العراقي دراسة في مساكن قضاء عنة الجديدة

إيمان علي العبيدي, عبدالله حسن النعيمي

Pages: 644-665 English

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Abstract

تستعرض هذه الدراسة التفاعل بين الأصالة والمعاصرة في تصميم المساكن الريفية في قضاء عنة الجديد. تهدف الدراسة إلى تحليل تأثير العناصر التقليدية في تشكيل البيئة المبنية واستدامتها، بالإضافة إلى استعراض الأساليب المعمارية التي تجمع بين التقنيات التقليدية والتقنيات الحديثة لتلبية احتياجات السكان المحليين. تم تنفيذ الدراسة من خلال مجموعة من المسوحات الميدانية والمقابلات مع السكان المحليين ومراجعة الأدبيات المعمارية والتخطيطية. توصلت الدراسة إلى أن دمج العناصر التقليدية في التصميم المعاصر يمكن أن يسهم في تعزيز الراحة والاستدامة البيئية للمساكن الريفية، ويسهم في الحفاظ على الهوية الثقافية للمنطقة.

Keywords

الأصالة المعاصرة المسكن الريفي العراق قضاء عنة العمارة التقليدية التصميم المستدام البيوت الريفية

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مقترح بناء نظام اداري لاختيار اسلوب التعاقد المناسب لاسلوب المقاول العام في قطاع التشييد

سعد حمد, محمد علي

Pages: 666-685 English

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Abstract

تهدف هذه الدراسة إلى تقديم مقترح لبناء نظام اداري يساعد في اختيار اسلوب التعاقد المناسب للمقاول العام في قطاع التشييد. يتناول البحث تحليل العوامل التي تؤثر على اختيار اسلوب التعاقد، مثل تكلفة المشروع، الوقت، الجودة، والمخاطر. يتضمن النظام المقترح مجموعة من الإجراءات والخطوات التحليلية التي تساعد في تقييم الخيارات المختلفة واختيار الأفضل منها بناءً على معايير محددة. كما يهدف النظام إلى تحسين إدارة المشاريع وزيادة كفاءتها من خلال توفير أداة تحليلية دقيقة وموثوقة. النتائج تشير إلى أن النظام المقترح يمكن أن يسهم بشكل كبير في تحسين عملية اتخاذ القرار واختيار أسلوب التعاقد المناسب في قطاع التشييد.

Keywords

نظام اداري اسلوب التعاقد المقاول العام قطاع التشييد إدارة المشاريع تكلفة المشروع الوقت الجودة المخاطر

4

أثر الأغلفة الديناميكية على كفاءة الأداء الحراري لأبنية المناطق الحارة الجافة

غادة محمد اسماعيل كمونة

Pages: 686-703 English

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Abstract

يتناول هذا البحث موضوع إيجاد أبنية كفوءة مناخياً تتميز أغلفتها البنائية بديناميكية عالية تمكنها من التفاعل والتكامل مع تغيرات المواسم في المناطق الحارة الجافة. يتضمن البحث تحليل العوامل التي تؤثر على كفاءة الأداء الحراري للأبنية، مثل استخدام الأغلفة البنائية الديناميكية والتصاميم المناخية الطبيعية. يهدف البحث إلى تعزيز الفهم للتصاميم المستدامة التي تتكيف مع التقلبات المناخية وتحسن من كفاءة الأداء الحراري للأبنية في هذه المناطق.

Keywords

أبنية ديناميكية كفاءة الأداء الحراري المناطق الحارة الجافة التصميم المناخي الأغلفة البنائية العمارة الطبيعية الاستدامة

5

VARIABLE VOLTAGE - FREQUENCY CONTROL OF A SINGLE PHASE INDUCTION MOTOR DRIVEN BY SHEPWM INVERTER

Ali Hussein Abdul-Jabbar

Pages: 3572-3582 English

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Abstract

This paper investigates the performance of a single-phase induction motor driven by a SHEPWM (Single Phase High Efficiency Pulse Width Modulation) inverter under variable voltage and frequency control. The study analyzes the steady-state performance of the motor, focusing on torque control and efficiency. The supply voltage-frequency law is selected to ensure correct motor operation over the entire speed range. The results demonstrate that variable voltage-frequency control can effectively manage the motor's speed and torque, making it suitable for applications requiring adjustable speed drives. The paper provides valuable insights into the design and implementation of SHEPWM inverters for single-phase induction motors.

Keywords

Single Phase Induction Motor SHEPWM Inverter Variable Voltage Variable Frequency Steady-State Performance Torque Control Power Electronics Adjustable Speed Drives

6

DOWEL ACTION BETWEEN TWO CONCRETES

Husain M. Husain, Nazar K. Oukaili, Hakim S. Muhammed

Pages: 3583-3605 English

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Abstract

This paper reports eight tests in which in-plane shear forces are applied across the joint between two different concretes forming a composite action. Shear can be transmitted across the joint either by interlocking of the aggregate particles protruding from each face or by shearing of the reinforcement crossing the joint1. Tests are conducted on initially cracked specimens by depending only on dowel action. The results of the tests are compared with theoretical results of the exponential equation presented by Millard and Johnson1. The computer program of Al-Shaarbaf using the nonlinear behavior of concrete is used to perform the analysis with inclusion of the exponential equation for dowel action in the interface layer. The program uses 20-node brick elements with embedded bar elements1. This program is also applied to Hofbeck et al. tests. The comparison shows that the experimental and the analytical results give good agreement where the difference between the two is between (2.5-5)%1. The use of the exponential equation gives good results when the concrete is assumed to be initially cracked as in construction joints.

Keywords

Composite Construction Construction Joints Shear Transfer Dowel Action Nonlinear Behavior of Concrete Finite Element Analysis Reinforced Concrete

7

STABILITY INDEX OF THE TREATED WATER FROM ALKARKH AND AL-RASHEED WATER TREATMENT PLANTS IN BAGHDAD CITY

Awatif Soaded Alsaqqar, Mohammed Abdul-Khalek

Pages: 3606-3619 English

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Abstract

This study evaluates the stability of treated water from the Alkarkh and Al-Rasheed water treatment plants in Baghdad City. The analysis focuses on the corrosivity of the water as it flows through the distribution system. The Ryznar Stability Index (RI) is used to assess the water\'s stability, with values ranging from 6.679 to 9.403. The study found that water from Alkarkh WTP in the north had higher RI values compared to Al-Rasheed WTP in the south, indicating varying levels of corrosivity. Factors such as calcium, alkalinity, total dissolved solids, and pH were analyzed to understand their impact on water stability. The results highlight the importance of monitoring water quality parameters to ensure the longevity of the distribution system and the safety of the water supply.

Keywords

Water Stability Stability Index Ryznar Index Metal Corrosion Water Quality Calcium Alkalinity Total Dissolved Solids pH

8

ALKYLATION OF BENZENE WITH LONG CHAIN OLEFINS OVER SOLID-ACID CATALYST

Abdul Halim A. K. Mohammed, Ali M. Ridha

Pages: 3620-3632

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Abstract

This investigation focuses on the production of linear alkylbenzene (LAB) through the alkylation of benzene with long chain olefins (C10-C13) using various prepared solid acid catalysts. The alkylation process was studied under different reaction temperatures, weight hourly space velocities, and constant pressure and benzene/olefin ratios1. The liquid-phase alkylation was carried out over tungstophosphoric acid supported on SiO2 with varying catalyst loadings (5%, 10%, 20%, and 30%). The catalyst with 30% loading achieved the highest olefin conversion to LAB (94%) at 398K and 5h-11. The reaction kinetics revealed that the alkylation process is second order, with the Thiele modulus indicating a diffusion-free regime and surface reaction as the limiting step. This study provides valuable insights into the design and optimization of solid-acid catalysts for industrial LAB production.

Keywords

Alkylation Benzene Long Chain Olefins Solid-Acid Catalyst Linear Alkylbenzene (LAB) Tungstophosphoric Acid SiO2 Support Fixed Bed Reactor Reaction Kinetics Thiele Modulus

9

TRANSMISSION OF A MULTIPLEXED EIGHT CHANNELS SUBCARRIER OPTICALLY INTENSITY MODULATED BASED ON MICROCONTROLLER Article Sidebar

Husam A. Mohammed, Hani J. Kbashi

Pages: 3633-3640 English

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Abstract

This paper presents the design and implementation of an optical fiber communication system for transmitting eight time division multiplexed (TDM) analog signals, each with a bandwidth of 500 Hz. The system utilizes the 8051 microcontroller as a parallel-to-serial converter on both the transmitter and receiver sides1. The transmitted signal is subcarrier intensity modulated using the Amplitude Shift Keying (ASK) modulation technique with a carrier frequency of 20 MHz. A laser diode (HFCT-5205) at 1300 nm wavelength was used as the optical carrier generator, and an InGaAs/InP PIN Photodiode (HFCT-S205) with a responsivity of 0.36 A/W was employed at the receiver side1. A single-mode fiber of 42 km length was used as the transmission channel. The system can be utilized in TDM fiber telephone lines operating at higher rates such as T3 (44.7 Mbps) and T3C (91 Mbps)1.

Keywords

Optical Communication System Microcontroller Subcarrier Optical Intensity Modulation Time Division Multiplexing (TDM) Amplitude Shift Keying (ASK) Laser Diode InGaAs/InP PIN Photodiode Single Mode Fiber RS232 Serial Transmission

10

COLOR SATELLITE IMAGES DENOISING USING WAVELETS

Hawrra H. Abbas Al-Rubiae

Pages: 3642-3656 English

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Abstract

This paper presents an adaptive method for denoising color satellite images using the Haar wavelet transform applied to the principle component bands of the satellite image. The first band (PC1), which contains about 90% of the image information, is processed to reduce noise while minimizing processing time and storage size. The results demonstrate that the Haar wavelet transform effectively reduces noise, improving the appearance and quality of the satellite images. This method offers a practical solution for enhancing the clarity and usability of satellite imagery in various applications.

Keywords

Satellite Image Denoising Wavelet Transform Haar Wavelet Principle Component Analysis Image Processing Noise Reduction Digital Image Processing

11

THE USE OF DENTAL RADIOGRAPHIC IMAGE ANALYSIS IN IDENTIFICATION OF DECEASED INDIVIDUALS

Hana\' S. Basheer, Ahmed A.H. Hindy

Pages: 3666-3672 English

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Abstract

This study explores the application of dental radiographic image analysis in the identification of deceased individuals. The aim is to automate the process using image analysis and pattern recognition techniques. Postmortem radiographs, including dental radiographs, are compared with a database of antemortem radiographs to find the closest match based on distinct features. The contours of teeth are used as the primary feature for matching, as they remain more invariant over time compared to other body features. The process involves two stages: radiograph segmentation with pixel classification and contour matching. A probability model is used to describe the distribution of object pixels in the image. The results on a database of over 40 images are promising, indicating the potential of this method for accurate and efficient identification.

Keywords

Dental Radiographic Image Analysis Forensic Dentistry Human Identification Postmortem Radiographs Antemortem Radiographs Image Segmentation Pattern Recognition Contour Matching

12

MODELING THE DISTRIBUTION OF (BOD) AND (TDS) IN PART OF TIGRIS RIVER WITHIN BAGHDAD

Ibtihaj A. Abdul Razzak, Abbas H. Sulaymon, R. Al-Zoubaidy

Pages: 3673-3691 English

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Abstract

This study develops a multi-cell serial model to simulate the distribution of pollutants, specifically Biochemical Oxygen Demand (BOD) and Total Dissolved Solids (TDS), in a 9 km stretch of the Tigris River within Baghdad. The study area includes four sewage pumping stations that discharge untreated wastewater into the river1. The river is divided into eleven cells of varying volumes, and the model is operated using field data collected from twelve stations along the river and four sewage pumping stations. The model predicts pollutant concentrations, which were verified against laboratory test results1. The findings indicate increased pollutant concentrations at discharge points, with BOD reaching up to 170 ppm and TDS up to 1100 ppm at certain points. The study suggests reducing the discharge rate of sewage pumping stations to maintain pollutant concentrations within acceptable limits, especially during low river flow periods1.

Keywords

Biochemical Oxygen Demand (BOD) Total Dissolved Solids (TDS) Water Quality Modeling Tigris River Pollution Control Sewage Discharge Differential Equations Field Data Collection

13

NUMERICAL ANALYSIS OF CONTROLLED MODULUS COLUMN FOUNDATION SYSTEM SUPPORTED EMBANKMENTS

Zainab Ahmed Alkaissi

Pages: 3691-3709 English

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Abstract

This research presents a numerical analysis of a deep foundation system known as Controlled Modulus Columns (CMC) for supporting embankments. The study employs the finite element method to model the elasto-plastic behavior of the embankment soil foundation. The model was verified against field data, showing that the effect of CMC can be negligible when soil strength, in terms of its internal friction angle, is high. However, with lower internal friction angles, CMCs can reduce surface deformation by approximately 12%. The study also found that surface deformation decreases with column diameter until it reaches a constant value at 0.5 meters. The maximum deformation was observed at the middle of the embankment, and considering CMCs in the soil embankment foundation reduced deformation by about 17%. These findings highlight the potential of CMCs in improving the stability and performance of embankments on soft soils.

Keywords

Controlled Modulus Column (CMC) Embankment Finite Element Method Elasto-Plastic Model Surface Deformation Internal Friction Angle Soil Strength Field Data Verification

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DEVELOPING A COMPUTER PROGRAM FOR MODELING THE STADIA MEASUREMENTS FOR TACHEOMETRY WORKS

Asma Th. Ibraheem, Afrah M. Daham

Pages: 3710-3730 English

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Abstract

This paper presents the principles of stadia measurement and a computer program called MSM (Modeling the Stadia Measurements) for tacheometry works. The program is formulated and written using Visual Basic language, Version 6, which is object-oriented and provides comprehensive tools to simplify programming tasks and design user interfaces. The MSM program is used to measure the lengths of traverse sides, check the accuracy of taped distances, uncover gross errors, and determine elevation differences between points. The program is particularly useful in the compilation of planimetric and topographic maps by field methods alone. The principles of stadia measurement using a transit, theodolite, or total station are discussed, and the program's application in surveying is demonstrated.

Keywords

Stadia Measurements Tacheometry Surveying Computer Programming Visual Basic User Interface Design Horizontal Distances Elevation Differences

15

PERFORMANCE EVALUATION OF THERMAL STORAGE POROUS WALL WITH VENTS USING PASSIVE SOLAR ENERGY

Saad M. Saleh, Hussein K. Saleem

Pages: 3730-3742 English

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Abstract

This study evaluates the performance of a thermal storage porous wall with vents for passive solar heating systems under Baghdad climatic conditions. The porous wall, made of gravel material, is compared with a conventional concrete wall using various control strategies. The analysis is conducted over a three-month heating season (December 1999 to February 2000) using computer simulations with MATLAB (Version 6.5). A mathematical model incorporating the governing differential equations of heat transfer through the wall and glazing under unsteady heat flow is developed using the control volume technique. The study investigates the effects of different wall thicknesses, porosities, insulation, glazing layers, and vents on the temperature distribution within the wall. The results demonstrate the effectiveness of the porous wall with vents in improving thermal performance and reducing energy consumption for heating.

Keywords

Thermal Storage Porous Wall Vents Passive Solar Energy Heat Transfer Computer Simulation MATLAB Control Strategies Baghdad Climate

16

GENERATION AND SIMULATION OF MESHING FOR INVOLUTE HELICAL GEARS

Mohammad Qasim Abdullah, Ali Ismael

Pages: 3743-3755 English

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Abstract

This paper presents a new method for the generation and simulation of meshing for involute helical gears. The proposed approaches are based on the imaginary application of two rack-cutters, one for pinion and the other for gear generation. The simulation of meshing for both aligned and misaligned helical gears provides insights into the shift of bearing contact on pinion and gear tooth surfaces and the function of transmission errors. The results demonstrate the effectiveness of the proposed method in accurately predicting the real contact path and transmission errors, making it a valuable tool for gear design and analysis.

Keywords

Helical Gear Gear Generation Meshing Simulation Bearing Contact Transmission Errors Rack-Cutters Gear Misalignment

17

EXPERIMENTAL PERSPECTIVE ASSESSMENTS FOR A PROPER REFRIGERANT ALTERNATIVE TO R-22 IN A WINDOW-TYPE AIR CONDITIONING UNIT

Ali Hussain Tarrad, Ameera Yaseen Salim

Pages: 3756-3775 English

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Abstract

This research focuses on finding an environmentally friendly refrigerant alternative to R-22 for use in window-type air conditioning units. The study evaluates the performance of R-407C as a potential substitute, considering its thermal properties and acceptable pressure and temperature ranges. Tests were conducted to compare the cooling capacity, power consumption, and coefficient of performance (COP) of the air conditioning unit using R-22 and R-407C. The results indicate that while R-407C has a higher pressure ratio and consumes more power, it offers a viable alternative with reduced environmental impact. The study highlights the importance of optimizing refrigerant mass flow rate, pressure, and temperature ranges to ensure efficient operation with the alternative refrigerant.

Keywords

Refrigerant Alternatives R-22 Window-Type Air Conditioning R-407C Cooling Capacity Power Consumption Coefficient of Performance (COP) Environmental Impact

18

ANALYSIS OF APPROXIMATED CURVED CRACKS IN HOMOGENEOUS AND GRADED MATERIALS

Hayder Fanoos Neamah

Pages: 3777-3792 English

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Abstract

This paper investigates the behavior of curved cracks in both homogeneous and graded materials. The study is divided into two stages: In the first stage, the influence of crack shape on crack-tip stresses, critical loads, and propagation direction is analyzed using a simple analytical model for homogeneous materials. This model is verified through finite element simulations using ANSYS. The results show that accurate predictions of mechanical energy release rate and crack deflection angle can be obtained from a smaller number of crack shape parameters. In the second stage, the concept is extended to curved cracks in functionally graded materials (FGMs). The study compares three approximations of crack shapes to the actual crack in isotropic and graded materials. The results indicate that piecewise linear crack shapes provide a significantly better approximation than straight crack shapes. The findings suggest that analytical solutions for piecewise linear cracks in graded materials would be very useful and should be a focus of future research.

Keywords

Curved Cracks Homogeneous Materials Graded Materials Fracture Mechanics Finite Element Analysis (FEA) Stress Intensity Factors (SIF) Crack Propagation ANSYS

19

PARAMETRIC STUDY OF LAMINAR NATURAL CONVECTION IN GLAZING ENCLOSURE

Karima E. Amori, Ahmed Mohammed Toima

Pages: 3793-3811 English

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Abstract

This study investigates the steady two-dimensional laminar natural convection heat transfer in a glazed rectangular enclosure under various conditions. The analysis considers different tilt angles ranging from 0° to 90°, Rayleigh numbers from 10^3 to 10^6, aspect ratios of 4, 5, and 8, and a Prandtl number of 0.7. The governing equations (continuity, Navier-Stokes, and energy equations) are solved using the finite volume method with the SIMPLE algorithm and a hybrid scheme to compute velocity vectors, temperature, pressure, and Nusselt number (local and average). Results indicate an increase in heat transfer rate with increasing Rayleigh number, with conduction being the dominant mode at low Rayleigh numbers. The tilt angle significantly affects heat transfer for Rayleigh numbers larger than 10^4. The findings are validated against previously published data, demonstrating the effectiveness and flexibility of the developed numerical procedure.

Keywords

Laminar Natural Convection Glazing Enclosure Rayleigh Number Prandtl Number Aspect Ratio Heat Transfer Finite Volume Method SIMPLE Algorithm Nusselt Number

20

SPLIT ASSIGNMENT WITH TRANSPORTATION MODEL FOR JOB-SHOP LOADING (CASE STUDY)

Khallel Ibrahim Mahmoud

Pages: 3812-3825 English

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Abstract

This paper analyzes the assignment problem in an industrial setting where the constraint of allocating only one job to each machine is relaxed, allowing jobs to be split and processed by multiple machines. The study demonstrates the application of a transportation model to solve this problem, optimizing job assignments and machine utilization1. A real-life case study is presented to illustrate the methodology, with the optimal solution obtained using POM software. The findings highlight the benefits of job splitting and transportation modeling in improving production efficiency and reducing job lateness.

Keywords

Assignment Problem Job Splitting Transportation Model Machine Utilization Job Lateness POM Software Real Life Case Study

21

THE EFFECT OF TEMPERATURE AND ACID CONCENTRATION ON POLARIZATION RESISTANCE FOR A CORROSION REACTION UNDER ACTIVATION CONTROL

Aparel Sarguis Yaro

Pages: 3831-3839 English

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Abstract

This study investigates the effect of temperature and acid concentration on the polarization resistance (Rp) of carbon steel in hydrochloric acid (HCl) solutions under activation control. Experiments were conducted at temperatures of 30°C, 40°C, 50°C, and 60°C in 1N, 3N, and 5N HCl solutions, both with and without the presence of phenylthiourea (PHTU) as a corrosion inhibitor. The polarization resistance was measured using the BETACRUNCH program developed by Green and Gandi. The results indicate that for a given acid concentration, the polarization resistance decreases with increasing temperature and decreasing inhibitor concentration. Additionally, for a given temperature, the polarization resistance decreases with increasing acid concentration, regardless of the presence of the inhibitor. These findings highlight the importance of temperature and acid concentration in controlling the corrosion behavior of carbon steel.

Keywords

Polarization Resistance Corrosion Reaction Activation Control Temperature Acid Concentration Carbon Steel Phenylthiourea (PHTU) BETACRUNCH Program Physical Adsorption Chemical Adsorption

22

SITE ASSESSMENT GUIDANCE A CASE STUDY (OUIREEJ SCRAP YARD)

Jathwa A. Ibraheem

Pages: 3840-3854 English

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Abstract

This paper presents a comprehensive site assessment of the Ouireej Scrap Yard in Iraq, focusing on environmental contamination and risk assessment. The study involves laboratory analysis of shallow soil and rainwater ponds, detecting contaminants such as PCBs, mineral oils, and heavy metals (copper, lead, antimony, and zinc). Although the detected levels of contaminants were relatively low, PCB contamination was found to be widespread. The paper discusses practical short to medium-term improvements, including controlling access to sites, land use zoning, licensing, and export controls. The findings emphasize the need for environmental practices to mitigate contamination risks, despite the challenges in wholesale reform of the scrap metal industry.

Keywords

Site Assessment Scrap Yard Environmental Contamination Risk Assessment PCBs (Polychlorinated Biphenyls) Heavy Metals Mineral Oils Land Use Zoning Licensing and Export Controls

23

RADAR PARAMETER GENERATION TO IDENTIFY THE TARGET

Waleed Mahmoud, A. K. Sharief, F. D. Umara

Pages: 3855-3867 English

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Abstract

This paper addresses the challenge of identifying and separating radar pulses from multiple sources received on a single communication channel. The study introduces a graphical user interface (GUI) to generate radar pulses, enabling the identification of pulses based on their unique characteristics. The proposed method enhances the reliability of radar systems in tracking and identifying targets, which is crucial for defense systems and electronic warfare applications. The paper outlines the principles of target tracking and electronic warfare systems, as well as the receiving system and radar signal description.

Keywords

Radar Parameter Generation Target Identification Electronic Warfare Radar Pulse Graphical User Interface (GUI) Signal Processing

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