Print ISSN: 1813-0526

Online ISSN: 2220-1270

Keywords : Keyword

Architectural Design of Random Number Generators and Their Hardware Implementations

Dr. Basil Shukr Mahmood; Sarmad Fakhrulddin Ismael

Al-Rafidain Engineering Journal (AREJ), 2014, Volume 22, Issue 2, Pages 50-59
DOI: 10.33899/rengj.2014.87322

Architectural Design of Random Number Generators
and Their Hardware Implementations
Sarmad Fakhrulddin Ismael Dr. Basil Shukr Mahmood
University of Mosul/computer University of Ninevah
Engineering Department
The architectural design of the random number generators for uniform
distribution, normal distribution, exponential distribution and Rayleigh distribution
using Box-Muller and inverse transformation method has been hardware implemented
on FPGA. Any of the random number generators can generate one sample every clock
cycle. The generators have been implemented on Xilinx Spartan 3E XC3S500E FPGA.
The designed generators work properly up to maximum frequency of 418.41MHz .The
outcome results of the generators have been tested by the chi-square test at a 5% level of
significance which provided the correct required distributions.
Keyword: Box-mulle, Chi-square, Inverse transformation, FPGA.
تصميم معمارية لتوليد الارقام العشوائية و ت ن ف ي ذ ه ا م اد ي ا
سرمد فخر الدين إسماعيل د. باسل شكر محمود
قسم هندسة الحاسوب/ جامعة الموصل كلية هندسة ألألكترونيات
المعمارية المصممة لتوليد الارقام العشوائية بتوزيع منتظم وتوزيع طبيعي وتوزيع اسي وتوزيع
.FPGA وطريقة التحويل العكسي تم بناءها ماديا باستخدام ال )Box-muller( )رايلي ( باستخدام طريقة ال
Xilinx اي واحد من مولدات الارقام العشوائية ممكن ان تولد رقم واحد في كل دورة. المولدات تم بناءها على
418.41MHz المولدات المصممة مناسبة للعمل بتردد مقداره .Spartan 3E XC3S500E FPGA
النتائج التي تم الحصول عليها من المولدات تم اختبارها بواسطة فحص مربع كاي بمستوى اهمية مقدارها
%5 والتي حققت التوزيع المطلوب.

The Effect of HARQ Procedure on the Performance of LTE System

Firas S. Al-Sharbaty; Safwan H. Fasola

Al-Rafidain Engineering Journal (AREJ), 2014, Volume 22, Issue 1, Pages 123-122
DOI: 10.33899/rengj.2014.86989

In this paper, the parameters of the LTE system in DL are investigated. These
parameters include the effect of the Hybrid Adaptive Repeat and Request henceforth
(HARQ) on the Signal to Noise Ratio (SNR), Block Error Rate (BLER), and throughput.
The paper deals with three cases of Channel Quality Indicator (CQI): 3,7 and 15.The
results showed that the HARQ procedure can improve the BLER and the throughput
when the retransmission between the evolved base station (eNodeB) and a User
Equipment (UE) increased

The Impact of Spatial Configuration Properties of The Courtyard on Special System Intelligibility of Islamic palaces

D. Hafsa Ramzi Alomri; Raeed S. Ahmed Alnumman

Al-Rafidain Engineering Journal (AREJ), 2014, Volume 22, Issue 1, Pages 40-55
DOI: 10.33899/rengj.2014.87027

The architectural cultural heritage of any nation is one of the most important basic components
that reflect the authenticity and depth civilization of that nations. Architecture as a mirror that
reflects all aspects of life (social, economic, technical, environmental, political) of the nation in
any age of the ages. many studies focused on research in the local historical properties of the
nation to define the architectural privacy (planning, design) to those of the nation. Many of the
studies that analysis of Islamic buildings in Arab city are indicated that courtyard is one of the
most important elements in both religious, civil architecture and often is used in the hot regions
despite differing effects of social, cultural and religious aspects indicator a success architect
solution for the different functional needs. The idea of courtyard is dominated the design ideas
in a different buildings where it was restrict the design process as it a restriction to the
different functional needs and reflected to the traditional architectural composition. Islamic
palaces buildings are represented various aspects of life, there are a reflection of social and
economic life and political across of different time periods that have passed the nation , and the
nature of the climatic conditions .
From the previous studies that focused on the courtyard in architectural environment specially
in Islamic palaces buildings appears that of the Intelligibility of the Special System of these
buildings is insufficiency and unclearness in this studies. this paper has taken this as a
research case , and will aims to be determined by Analysis a select group of various and different
functional type of Islamic palaces

Vegetation Loss Detection of Nineveh Province Using Remote Sensing Images Based on Ant Colony Algorithm

Younis M. Abbosh; Turkan Ahmed Khaleel; Joanne H. Al-Khalidy

Al-Rafidain Engineering Journal (AREJ), 2013, Volume 21, Issue 6, Pages 60-71
DOI: 10.33899/rengj.2013.82386

Nineveh province in Iraq has experienced a process of land cover conversion and vegetation loss especially in last decades. It is important to get accurate information on vegetation loss and changes in areas that are used for agriculture.Among the most effective methods to study and get information about this phenomenon is remote sensing technology.
Since classical approaches lack of accuracy, artificial intelligence has been introduced to strengthen feature detection which leads to better classification.This paper uses ant colony algorithm to study and classifypart of Nineveh province land into sixclasses. These are Agriculture land/flood plane, Water, Outcrop, Origin of early sand sheet, Desertable area, and Sand dunes.The variation in these six classes from 1987 to 2009 is shown. Results show that agriculture region and flood plain decreased from around 31% in 1987 to 11.2% of total area in 2009 while origin of early sand sheet and desertable area increased from 42.7% to around 49%. Beside that sand dune appears in 2009 to form about 26.47% of total area under study.

Keyword-Remote Sensing, Classification, Ant colony algorithm, Vegetation Loss.

Performance of using crushed glass and sand as a filtration media in purification drinking water

AbeerHashim Hassan

Al-Rafidain Engineering Journal (AREJ), 2013, Volume 21, Issue 6, Pages 100-113
DOI: 10.33899/rengj.2013.82369

This research includes performance of using crushed glass as a filtration mediawith sand depending on the variation in turbidity levels in the raw water
(5, 10, 25, 50, 75, 100 and 200) turbidity unit, type of the filter , type of filtration and the depth of the filter (25, 35 and 55 cm.) within filtration rate (8) m/hr. A total of (9) different configuration filters with different types and different depths of the filtration media, (6) of them are single-media and (3) are dual media which ranged between (25 and 55) cm and the number of the samples was (196) of the water resulting from the filters. The results showed that the glass media has the capability to remove turbidity and provide quality effluents conform to international and Iraqi specifications (less than 5 NTU).Effluent turbidity well below (1 NTU) is also achieved. In addition to that, the best results were obtained of removing turbidity when using the crushed glass as a filtration media in the dual filters as upper layer and with a removal percentage that reached (98.4%). For the single filters, the study showed the superiority of the glass filter over the sand filter in terms of turbidity removal at the preliminary levels in raw water in which turbidity is less than (25 NTU). While the sand filter was superior over the glass one in turbidity levels which exceed (25 NTU).
Keyword: filtration media, crushed glass, filtration rate, direct filtration, single& dual filters

Analysis of Hydraulic Characteristics of Cutthroat Flume-eng

Hana A. Hayawi; Amal A. Yahya; Dr. Ghania A. Hayawi

Al-Rafidain Engineering Journal (AREJ), 2013, Volume 21, Issue 4, Pages 131-141
DOI: 10.33899/rengj.2013.77387

The aim of this research is to calculate experimentally the coefficient of discharge for cutthroat flume. Nine models were contracted with different angles (α=30°, 45°, 60°), for each angle, Three ratios of width of cutthroat to width of channel Bc/B were used (Bc/B%=20, 33.3, 50); the slopes of the channel were changed five times (S=0.0, 0.001, 0.002, 0.003, 0.004) for each ratio. The results show that the coefficient of discharge Cd increases as the slope S increases, and as the ratio Bc/B, is the ratio of head of water through cutthroat to width of cutthroat hc/Bc, critical depth through cutthroat to width of cutthroat yc/Bc increases, and for a constant ratio Bc//B, Cd increases as α increase. An empirical model was predicted to calculate the Cd in terms of the perimeters ( S, hc/Bc, yc/Bc, Bc/B,, and α), finally the water surface profiles were drawn and there were in a continuous trend.
Keyword: discharge coefficient, cutthroat flume

Effect of high temperature on Bond Strength in entrained air Reinforced Concrete(Arbic)

Dr. Abdul Hakeem Hamed Ahmed; Yaman Huthaifa Shaker

Al-Rafidain Engineering Journal (AREJ), 2013, Volume 21, Issue 1, Pages 57-67
DOI: 10.33899/rengj.2013.67345

This research aims to study the effect of temperature on bond strength in air entrained concrete and to find the effect of adding entrained air on the properties of the fresh and hardened Concrete under the influence of high temperatures of different levels (20, 200, 400, 600 ºC). These properties are compared with those for normal concrete . In case of concrete structures exposed to an unexpected fire, changes are found in the properties of the concrete constituents, These changes are evaluated to assess the performance of these concrete structures and determine whether structures are safe or not .The research work includes an experimental study of the mechanical properties of the hardened concrete , and the effect of high temperature and entrained air admixture on concrete behavior including, compressive strength, splitting tensile strength, stress – strain relationship (modulus of elasticity) and bond strength between reinforcement and concrete. The work includes four different percentage of air entrained admixture (Sika_Aer) (0, 0.5, 1.0, 1.5 %) by weight of cement. The effect of these variables on the bond stress between concrete and reinforcement as a result of tensile forces using pullout test are investigated. The Results show that the failure for reinforced concrete bond strength depends on diameter of the steel bar used (Ø10 , Ø 12 and Ø 16 mm) , heating temperature for specimens after (28) days of water curing and also depends on the amount of admixture in concrete (Sika-Aer).

Keyword: Concrete, Bond Strength, Entrained air, High temperature

Design and Fabrication of Thin Film a-Si/Al2O3 Infrared Filter

Dr. Khalid Khaleel Mohammad; Mr. Saad Gazai

Al-Rafidain Engineering Journal (AREJ), 2012, Volume 20, Issue 4, Pages 60-68
DOI: 10.33899/rengj.2012.54156

Long-wavelength infrared filter operated at various temperature are critical for imaging applications. In this paper anew type of infrared filter is investigated, this infrared filter uses a crystalline silicon substrate coated with multi layers of aluminum oxide (AL2O3) and amorphous silicon (a-Si) to produce the multi layers thin film infrared filter a-Si/AL2O3 operating in the range (8-14)um. Amorphous silicon is used in this paper due to its high refractive index, while AL2O3 due to its low refractive index material. The a-Si/ AL2O3 thin film structure were designed using the Thin Film Design software (TF Calc 3.5.6 version). The simulated results obtained shows that the transmittance of the a-Si/ AL2O3 infrared filter with 19 layers is about 90% for (8-12.5) µm wavelength, while it is about 95% for 47 layers for (8.25-13.25) µm wavelength. The investigated filter was fabricated using vacuum evaporation process and the results obtained were comparable with the simulated one. The fabricated a-Si/ AL2O3 filter is compared with the Ge/ZnS infrared filter and it is found that the results is comparable but the cost of the fabricated filter is small compared to the Ge/ZnS filter.

Keyword: Infrared Filter, Silicon, Aluminum Oxide.

Design of Delta-Sigma ΣΔ based Fractional N PLL Frequency Synthesizer for GSM Mobile Systems

Saad Wasmi Osman Luhaib; Dr. Khalid Khaleel Mohammed

Al-Rafidain Engineering Journal (AREJ), 2012, Volume 20, Issue 3, Pages 26-34
DOI: 10.33899/rengj.2012.50474


This paper presents the design of Delta-Sigma ΣΔ based fractional N PLL frequency synthesizer for GSM mobile systems. The loop filter is one of main element in fractional-N ΣΔ synthesizer because it shapes the noise spectrum of quantization error and reduce the spurious level in the pass band of PLL. The effect of loop filter order is studied and it is shown that by increasing the order of the loop filter, the phase noise performance will be improved, although this requires careful design consideration, as the PLL is prone instability. It's shown that the 3rd order loop filter and 3rd order ΣΔ modulator gives the best performance with reducing phase noise (13dBc/Hz ) and spurious noise (44dBc) of the output signal.
Keyword: PLL, Frequency Synthesizer, ΣΔ Modulator, Fractional-N, GSM mobile systems.

Numerical Investigation of Natural Convection Heat Transfer in Porous Medium Saturated With Carbon Dioxide in Supercritical State

Dr. Amir S. Dawood; Younis M. Najim; Mohanad K. Radhi

Al-Rafidain Engineering Journal (AREJ), 2012, Volume 20, Issue 2, Pages 86-97
DOI: 10.33899/rengj.2012.47286

Natural convection in a porous medium saturated with supercritical carbon dioxide (CO2) whichis bounded by square cavity is studied numerically by solving the governing Darcy equation using finite-differences method.The side walls of cavity were assumed to be isotherm with fixed temperature difference of 0.0152K, while the upper and lower sides are assumed to be thermally insulated, the aspect ratio is chosen to be one, with cavity height of 0.01 m, the Darcy number adopted is , usually these values lead to very small modified Rayleigh number. Despite all of this, the state of supercritical takes the fluid (CO2) to a huge changes in its properties ( ) which allow to transfer a relatively large amount of heat between the hot and cold sides of the cavity with a very small temperature difference with maximum Nusselt number over 13 . The results of this study show clearly these concepts. The state of carbon dioxide in supercritical region is specified by reduced pressure and reduced temperature , the reduced temperature and pressure have been varied as .
Keyword: Natural convection, porous media, supercritical carbon dioxide

The effects of Reduced Temperature and Pressure on Natural Convection in Rectangular Cavity Filled with a Supercritical Water: a Benchmark Numerical Solution

Younis M. Najim

Al-Rafidain Engineering Journal (AREJ), 2011, Volume 19, Issue 3, Pages 55-68
DOI: 10.33899/rengj.2011.27022

In this paper, natural convection heat transfer of supercritical water in rectangular enclosure has been investigated in various values of reduced temperature (0.955 1.205) and pressure (1.2 2.0). The right and left sides of enclosure considered to be isotherm with a temperature difference of , while the lower and upper sides of the enclosure was thermally insulated. The width of enclosure is 0.004m. Calculations were performed for Rayleigh number ( ), Prandtl number ( ). The values of Ra and Pr are governed by the fluid temperature and pressure which are controlled by reduced temperature( ) and reduced pressure ( ). Streamlines, isotherms and mean Nusselt numbers are presented. It is found that the temperature distribution and flow field are affected by the reduced temperature and pressure. The results also show that the maximum Nusselt number could be obtained at the same specification of geometry and temperature difference increases as the pressure reach the critical pressure.
Keyword: Natural convection, supercritical Water, reduced temperature and pressure

Design characteristics that affect usage efficiency of reading spaces in University Libraries

Niam Behnam Manona

Al-Rafidain Engineering Journal (AREJ), 2011, Volume 19, Issue 1, Pages 93-109
DOI: 10.33899/rengj.2011.27839


Post occupated buildings have formed a subject examined by several architectural studies and arose in their concluion the importance of suitable designing concepts that promote the efficiency of its use arose these ideas into light was greatly envisaged in the university libraries’ buildings in general and their reading spaces in particular, which dominate real interaction among their designing characteristics and users’ preferences.The research discusses the significance of what have been mentioned above and the reality of knowledge related to it in the architectural reality to extract the special problem related to the designing factors that are invested by designers in reading spaces which have an influence on increasing their use efficiency.
Evaluation of several previous studies has led to identifying knowledge deficiency and thus the research problem was represented by unclear theoretical knowledge which determines and describes the set of the affecting designing factors in the usage efficiency and determining its aim by revealing it. As to its methodology; it was represented by building up a theoretical framework included two major aspects one of which discusses the designing factors regarding the reading space; whereas the second includes the variables regarding the usage efficiency. Then the theoretical framework was applied in the field aspect on selected models from the libraries of the university of Mosul and determining the research population among users.
Conclusions have shown an evident variation between the effect of the designing factors on the use efficiency such that enable the designer investing, activating and determining the priorities of future designing treatments.
Keyword: Usage efficiency of building .

Enhanced Performance of FH Detection System Using Adaptive Threshold Level

Ammar Abdul-Hamed Khader

Al-Rafidain Engineering Journal (AREJ), 2010, Volume 18, Issue 5, Pages 107-122
DOI: 10.33899/rengj.2010.32906

This work investigates the evaluation performance of detection system for Frequency Hopping (FH) signals based on Fast Fourier Transform (FFT) with proposed decision circuit based on Adaptive Threshold Level (ATL), where the threshold level changes its value automatically without manual intervention depending on the estimated values of (SNR) in the channel, the level will be high when the noise is high and vice versus. A comparison in evaluation performance were made with a conventional mode where the decision circuit based on Manually Change Threshold Level (MCTL) done by the detector according to its observation on sensing the Signal to Noise Ratio (SNR). The results shows that the proposed mode (adaptive) is give best results for probability of detection PD and probability of false alarm PF comparing with the (Manually Change). Also the results of (adaptive) are compared with that theoretical computation and gives a very small error for high noise while vanish for low noise.
Keyword: Frequency Hopping, Adaptive Threshold Level, Manually Change Threshold Level

The Effect of Grain Boundary on the electrical and photoelectrical characteristics of Au/p-Si Schottky Diode

Dr. Khalid Khaleel Mohamed

Al-Rafidain Engineering Journal (AREJ), 2010, Volume 18, Issue 3, Pages 10-18
DOI: 10.33899/rengj.2010.28455

This paper is intended to study the influence of the grain boundaries on the electronic and optoelectronic behavior of Au/P-Si Schottky diode. These diodes were fabricated by evaporation of gold layers onto polycrystalline silicon wafers using vacuum evaporation technique. The current-voltage characteristics at different grains boundary and temperatures, spectral response were investigated. It is found that the Schottky barrier height for Au/P-Si diode obtained form I-V and spectral response characteristics are depends mainly on the surface grain boundary density and state density.
Keyword: Grain Boundary, Au/p-Si, Schottky Diode.

Improved Performance of ZnO/n-Si Solar Cells

Dr. Khalid Khaleel Mohamed

Al-Rafidain Engineering Journal (AREJ), 2010, Volume 18, Issue 3, Pages 19-28
DOI: 10.33899/rengj.2010.28456

This research is intended to improve the performance of ZnO/n-Si solar cells. The structures were fabricated using thermal evaporation techniques. The indium dopant at suitable heat treatment is used to enhance the electrical characteristics of ZnO layer resulting in reducing atmospheric condition to change the stiochiometry of ZnO layer. The electric properties of the fabricated samples are dependent on many parameters such as annealing temperature, ZnO layer thickness, Indium layer thickness and temperature. The indium layer were deposited at different thickness (10-30) nm during the fabrication of the ZnO/n-Si solar cells. The resultant samples has been studied and the results obtained show an improvement in the efficiency of 0.4% compared with the standard ZnO/n-Si solar cell.

Keyword: ZnO/n-Si, Indium, Thermal Evaporation

Effect of Liquids type on some Engineering Properties of Limestone Rock from Eski-Mosul

Thamer M. Nuri; Ahmed M. Nejm Al-Deen

Al-Rafidain Engineering Journal (AREJ), 2010, Volume 18, Issue 3, Pages 1-12
DOI: 10.33899/rengj.2010.28435

This research studied the effect of liquids on the Engineering properties of the Limestone rocks. The liquids used were: crude oil from Ain Zala, crude oil from Kirkuk, natural ground Water.
The Limestone used was brought from Eski Mosul situated at 45 Km north west of Mosul. Both the compressive and tensile tests were conducted on the Limestone rock specimens in the dry and saturated case using;Uniaxial, Triaxial Compression and Bending tests.
The tests showed that saturation with any one of the liquids lead to a decrease of both compressive and tensile strength. The greatest decrease occurred when ground water was used to saturate the specimens, and it was also noted that the effect of saturation gave greater percentage of decrease on the compressive than the tensile strength.
The study also showed that liquids lead to decrease in cohesion ( c ) and the Friction angle (Φ) obtained from triaxial test. The liquids used for saturation didn't have clear effect on the type and mode of failure on all specimens tested .
Keyword: σc:Compressive strength σt: Tensile strength

Design and Simulation of an Optical Gigabit Ethernet Network

Omar Ahmed Yousif; Salah A. Jaro Alabady

Al-Rafidain Engineering Journal (AREJ), 2010, Volume 18, Issue 3, Pages 46-61
DOI: 10.33899/rengj.2010.28461


This paper deals with the design and simulation of an optical gigabit Ethernet using OPTSIM 3.6 packet software. The main aim of the proposed design is to build a MAN optical network using one-gigabit Ethernet technique, and what are the necessary requirements to build these networks. As a case study, all states center are connected as Star – Bus topology using layer2 and layer3 optical switches. In addition, in this paper one-gigabit optical transmitter and receiver are designed to work as a node in the network topology. Further more, the benefits of using L- Band wavelength for transmission take in consider the linear and non-linear effects on fiber optic is presented.

Effect of Personal Aptitude on Creative Fluency in Architectural Design The Students and Graduates of the Department of Architecture in Mosul

Farhan Awad Jasim

Al-Rafidain Engineering Journal (AREJ), 2010, Volume 18, Issue 2, Pages 73-99
DOI: 10.33899/rengj.2010.28188

The research handles creation as a personal ability focusing on the study of creative fluency as the most important ability in creation and in the creative architectural practice. Fluency which originally consists of many types depends only on velocity and easiness of creating ideas and alternatives without considering their originality. The problem of the research is represented in questioning the effect of the personal aptitude on the range of the creative fluency. The case study of problem was examined on the students and graduates of the Department of Architecture in Mosul University. The aim of the research is trying to find out the nature of this effect. Hence, finding the way of future predication of the extent of the ability of creative fluency of the applicants to study architecture in the Iraqi academic establishments. The research adopts and design an experiment to clarify the possibility of the existence of a quantitative index of the creative fluency depending on testing of completing architectural forms. The research finds out that architects of motional personality are more fluency of those of rational personality. It also finds out that increasing the skill of freehand drawing and the experience as well as motivation will greatly contribute in increasing their creative fluency.

Keyword: Creation, Fluency, Personal Aptitude, Measure of personality, Exam of creation.

The Use Of Used Engine Oil As Anadmixture In Concrete With High Temperature

I.H. AL-Zubady; Dr. A.H. Ahmed

Al-Rafidain Engineering Journal (AREJ), 2009, Volume 17, Issue 6, Pages 1-13
DOI: 10.33899/rengj.2009.43617

The aim of this research is to study the effect of (Used Engine Oil) (UEO) on the properties of fresh and hardened concrete and its effect on the properties of the hardened concrete under high temperature, the (UEO) used as a plasticizer material, adding an air-entrained to the fresh concrete, thus improving workability of the fresh concrete. The (UEO) is used as percentage of cement weight (0.1,0.15, 0.2%) ,the 28 day concrete is exposed to different levels of high temperature (200,400,600°C) for 1.0 hr, the concrete samples were tested after
24 hr of cooling, two methods were used to add the (UEO), First Method: adding the (UEO) during the mixing process (mixing the dry materials and water after that the used engine oil was added), The Second Method: An emulsion mixture consisting of oil and water was prepared for the different percentages of additions this emulsion was used after mixing the dry materials, the mixing time was 4 minutes. Results showed that the effect of using the (UEO) is similar to that of air-entraining chemical to fresh concrete, its effect appears on the (initial & final setting time, slump and air content) and also affects the properties of hardened concrete.
Keyword: used engine oil, concrete, high temperature, air-entrained.

Flexural Behavior Of R/C Beams With Externally Bonded Gfrp Sheets

Bayar J. Al-Sulayfani; Ashtar S. Al-Luhybi

Al-Rafidain Engineering Journal (AREJ), 2009, Volume 17, Issue 6, Pages 11-27
DOI: 10.33899/rengj.2009.43586

During the latest decades there has been a significant increase in using FRP (Fiber Reinforced Polymers) as a main material for external reinforcement in the construction industry.Externally bonded FRP sheets have been used to increase moment capacity of flexural members and to improve confinement in compression members. This paper summarizes the result of experimental and analytical studies on the flexural strengthening of reinforced concrete beams by external bonding of glass fiber reinforced polymer sheets to the tension face of the beam. Four beams, three with different thickness of GFRP sheets and one without GFRP sheets were tested using third-point loading over a span of 900mm.The tests were carried out under load control. The results indicate that the flexural strength of the beams increased significantly as the thickness of the sheet increased. Analytical study using a computer program based on strain compatibility is presented to predict the ultimate strength and load-deflection behavior of the beams. When the experimental results were compared with theoretical ones, good acceptable agreement was obtained which make it possible to consider and recommended this model in the design.

Keyword: Analytical Study, Flexural Behavior, GFRPSheets, Strengthening.

Spatial Configuration properties of Islamic Palaces

Raeed S. A. Al-numman

Al-Rafidain Engineering Journal (AREJ), 2009, Volume 17, Issue 5, Pages 91-108
DOI: 10.33899/rengj.2009.43401

In recent years, trends focusing on exploration the architectural identity through the study of the domestic architecture properties, have emerged in order to find an appropriate architecture therefore many studies have recently talked this topic including Arabic – Islamic societies . some of them have focused on studying the compositional relation of architectural products . others have focused on studying limited properties and phenomena and others , including this paper , have focused on studying the properties of specific buildings (Islamic palaces) for limited design aspects (architectural palaces) in the Islamic architecture .
The literature review of the concept of Special Configuration in Islamic building shows the absence of the clear and specific limitation of the properties of the special Configuration of the Islamic buildings . the paper has taken this problem to be the problem of the research . The aim of the research is to give a clear and specific limitation of the properties of the Special Configuration of the Islamic palaces by comparing them with their counterpart in the palaces of Mesopotamia and the adjacent regions . Space Syntax analysis has been applied to assess the characteristic of the building type .
The conclusion solved that there is clear idiosyncrasy of the Special Configuration of Islamic palaces due to the effect of Islamic belief . Some of these palaces have similar properties of these of Mesopotamia because of social values , others because of the environmental effect .
Keyword : Islamic architecture , palaces , spatial configuration

The Utilization Of Concrete Maturity To Predict Its Compressive Strength Under Variable Conditions

I.H. AL-Zubady

Al-Rafidain Engineering Journal (AREJ), 2009, Volume 17, Issue 3, Pages 1-15
DOI: 10.33899/rengj.2009.42933

The aim of this research is to study the maturity of concrete for predicting in-situ compressive strength for any concrete mixture in any structural work based on the laboratory testing results of several concrete specimens, then finding a relationship between compressive strength-maturity mathematical models that can be used for predicting the compressive strength. Three type of mixes were used; first mix contains ordinary Portland cement (O.P.C), second mix contains sulphate resisting Portland cement (S.R.P.C), third mix contains ordinary Portland cement with an admixture (caco3) of (15%) replacement of cement weight.
Compressive strength tests at different ages) 3,7,14,28( days and different temperatures(27±2°C) (80.6±2°F)&)34±2°C) (93.20±2°F) and curing conditions of (moist and air cured). The maturity was found for concrete samples using the Plowman technique with the datum temperature at (-11.6°C) (11°F(,the actual compressive strength values found from laboratory testing were compared with the predicted compressive strength values from Plowman equation to estimate the margin of the errors involved, the error was found to be reasonable especially for the moist cured samples.

Design of Antiwindup AVR for Synchronous Generator Using Matlab Simulation

Abdelelah Kh. Mahmmod

Al-Rafidain Engineering Journal (AREJ), 2009, Volume 17, Issue 3, Pages 90-98
DOI: 10.33899/rengj.2009.42922

Automatic voltage regulator AVR is designed for synchronous generator utilizing anti windup PI controller, to keep the terminal voltage of the generator to the rated value. The simulation of the synchronous generator is done using Matlab instructions which based on d-q axes models and the designed AVR as anti wind up PI controller. The results shows when an inductive load is applied to the generator the terminal voltage drops , the AVR is automatically increasing the excitation to get rid of this the disturbance as fast as possible.

Keyword: Anti windup PI, AVR, Synchronous generator.

Digital Hardware Implementation of Artificial Neurons Models Using FPGA

ad Ahmed Al-Kazzaz; Rafid Ahmed Khalil

Al-Rafidain Engineering Journal (AREJ), 2009, Volume 17, Issue 2, Pages 12-24
DOI: 10.33899/rengj.2009.38764


This paper present the digital implementation of multiply-accumulate (MAC) circuit of artificial neuron using FPGA (Field Programmable Gate Array) including three types of nonlinear activation functions: hardlims, satlins and tansig. A VHDL hardware description Language codes are used to implement the neuron using XC3S500E-FG320 Xilinx FPGA device. The simulation results obtained with Xilinx Foundation 8.2i software are presented. The results are analyzed in terms of usage percentage of chip resources and maximum working frequency.

Keyword:- Artificial Nouron , FPGA , Neural Network

Performance Improvement of Broad Crested Weirs

Inam A.K. Juma; Bahzad M.A. Noori

Al-Rafidain Engineering Journal (AREJ), 2009, Volume 17, Issue 2, Pages 95-107
DOI: 10.33899/rengj.2009.38864

In order to improve the performance of broad crested weirs, forty weir models were manufactured and tested and two hundred thirty six experiments were conducted in a laboratory horizontal channel of 10m length, 0.3m width and 0.45m depth for a wide range of discharges. The performance of broad crested weir was improved by introducing an upstream face slope, rounding upstream corner and capping the upstream corner with a semi-cylinder in order to reduce the effect of flow separation. Analysis of experimental results showed that introducing an upstream slope face to square edge broad crested weir improved the performance and gave higher values of discharge coefficient. Rounding upstream corner increased the values of discharge coefficient and improved the performance of the weir. Also, capping the upstream corner with semi-cylinder improved the performance of the weir and gave higher values of discharge coefficient. Two empirical equations were obtained to estimate the value of discharge coefficient in terms of effective head to crest height ratio, upstream corner radius to crest height ratio and radius of cap to crest height ratio with high correlation coefficients.
Keyword :-Performance , Broad crested Weirs

FPGA Implementation of a Multilayer Perceptron (MLP) Network

Nour talal gadawe; Rafid Ahmed Khalil

Al-Rafidain Engineering Journal (AREJ), 2009, Volume 17, Issue 1, Pages 1-13
DOI: 10.33899/rengj.2009.38557

In this paper, we suggest a method for designing and implementing of multilayer Perceptron (MLP) neural network based on backpropagation (PB) learning algorithm. The method is described using very high speed integrated circuit hardware description language (VHDL), that used in developing the designs of a very large scale integration (VLSI). Firstly artificial neuron with sigmoid activation function has been designed and implemented which is considered as a basic unit of MLP. The MLP network is trained by BP algorithms, in the Matlab environment in order to obtain the ideal parameters of the network. Then hardware implementation of MLP on FPGAs, of types Spartan 3E and Virtex4 is achieved by using integer format and floating point format respectively . A comparison is done between the two arithmetic formats of MLP implementations on FPGAs.

Keyword: MLP neural networks , floating-point (FLP) arithmetic, FPGA, VHDL.

Multi – Agents Network Based Virtual Manufacturing Using Oracle Net Services

Sama T. Al-Aubaidy; Abdulsatar M. Khudur; Akela M. Al-Atroshi

Al-Rafidain Engineering Journal (AREJ), 2009, Volume 17, Issue 1, Pages 32-47
DOI: 10.33899/rengj.2009.38409

The current research concentrates on special objectives in Innovating and applying a network among the Multi-Agents in the Designed Proposed System , by the use of (Oracle) language to produce a new product by using the available potentialities of the company or by cooperating with partners in the future within the concept of the Virtual Manufacturing. Every Agent (user) has its own roles and privileges. The application results indicate that the VM philosophy has been performed efficiently by the use of the Multi–Agents Network which is managed and attains integration by the server Agent that uses the available interfaces as Oracle language capabilities such as DDE, OLE and run–product.
Also, The application results have confirmed that there is a possibility to add easily a new client : Hardwarely: by Updating the network and connecting a new client by the use of one of the following oracle tools: - Oracle Net 8 Assistance, - SQL * Net Easy Configuration , , Oracle Net 8 Assistance.lOracle Net 8 Easy Configuration . Softwarely: to the designed system by the use of the Enterprise Manager console as a wizard or through the SQL plus worksheet.
Keyword: Virtual Manufacturing, Multi- Agents Network, Oracle Security

Multi Rate Audio Coding Based On Combining Wavelet with DCT Transform

Adnan I. Hussein

Al-Rafidain Engineering Journal (AREJ), 2008, Volume 16, Issue 5, Pages 1-8
DOI: 10.33899/rengj.2008.44849

In this paper an efficient algorithm proposed to encode the audio signals with multirate capability. The algorithm based on combining discrete wavelet with DCT transform for maximum decorrelation. The coefficients of the frame are scaled and encoded using non uniform quantizer. The main features of this algorithm are: low complexity and near transparent audio quality resulted in the range 48 – 64 Kbps for most SQAM signals. The algorithm outperform much better than DWPT with SPIHT algorithm previously.

Keyword : wavelet , DCT , audio , coding , Huffman , and psychoacoustics.

Performance Improvement Of Cellular Systems Using MIMO-OFDM

S. A. Mawjoud; W. M. Abdul-Latef

Al-Rafidain Engineering Journal (AREJ), 2008, Volume 16, Issue 4, Pages 69-79
DOI: 10.33899/rengj.2008.44733

The combination of multiple-input multiple-output (MIMO) system with OFDM techniques is regarded as a promising solution for enhancing the data rates of next-generation wireless communication systems.
SDM is implemented to transmitted different signals simultaneously at the same carrier frequency and to detect the transmitted signals using many techniques such as zero frequency, minimum mean square error with and without decision feedback and maximum likelihood decoding.
Furthermore, orthogonal frequency division multiplexing technique included in the simulation process using the parameters of the IEEE 802.11a standard. The fading channel is modeled by exponentially – decayed Rayleigh fading channel which is based on the indoor WLAN, Least Square (LS) method is used to estimate the channel for each subcarrier.


Effect of chisel plow shanks shape on power Requirements of Tractor

Mahmood Elias Ahmed Al-Taee; Saad Abdul Jabbar Al- Rajaboo

Al-Rafidain Engineering Journal (AREJ), 2008, Volume 16, Issue 4, Pages 17-26
DOI: 10.33899/rengj.2008.44742

This study was carried out at two sites of different soil texture, clay and a clay loam during the season of 2005 – 2006 In Mosul .A plough of three different shank shapes have been used . These shapes were vertical, inclined forward and curved with two plough depths of 8-12 cms and 13-17 cms successively with three speeds 3.70, 7.15 and 9.64 km/hour. In order to study the effect of the shank shape on the power requirements -which include the draft force, rate of fuel consumption, slippage ratio and the power loss due to slippage. The two experimental farms have been designed by the use of (RCBD) with three factors and replications. The main results of this study, The vertical shank outperformed at the first site and the inclined forward outperformed at the second site in recording the lowest requirement with their means, the 8-12 cm depth outperformed at the two sites with their means in recording the lowest power requirement, the (3.70) km/ hour speed recorded the lowest power requirement except fuel consumption at the two sites with their means, The second site (clay loam texture) outperformed records the lowest power requirements.and at the effect of interaction between the sites, shank shape, depth and speed on the studied properties the inclined forward shank at depth of (8-12) cm and at speed of (3.70) km/hour gave the lowest power requirement at the second site except fuel consumption.
Keyword: Tillage – Chisel Plow Shanks –– Power requirement

Effects Of Camber Of Beam On Behavior Of Single Span Portal Frames

Kanaan Sliwo Youkhanna Athuraia

Al-Rafidain Engineering Journal (AREJ), 2008, Volume 16, Issue 4, Pages 30-37
DOI: 10.33899/rengj.2008.44725

An attempt is made to study the effect of camber on the behavior (deflection and failure load) of single span portal frames under concentrated load. Two types of cambering were used, the first by cambering both top and bottom surfaces of the beam and the second by cambering the bottom surface only (the top surface is kept leveled) which is more acceptable from point of view of uniformity of super imposed dead load distribution.
There is a considerable effectiveness of the camber on the failure load compared with straight beams (without camber). Also, there is effectiveness considering )dead+live( load deflections for cambered beams compared with straight beams.
Keyword : Membrane Action, Camber, Concentrated Load, Deflection, Failure.

Properties and Behaviour of Lightweight Concrete Containing Polystyrene Granulars

Salwa Mubark Abdullah; Usama Abdullah Ameer

Al-Rafidain Engineering Journal (AREJ), 2006, Volume 14, Issue 3, Pages 17-26
DOI: 10.33899/rengj.2006.45331

In the current research polystyrene particles are added to the concrete mix to produce six strips of reinforced slabs, in order to study the strips bearing capacity at the age of 56 days then later at 10 years. A selected mix of specific w/c is used; the main properties of the mix were studied from the results of casting cubes and beams. The results indicated that the L.W.C containing the polystyrene particles may be used to manufacture reinforced slab strips, in addition and as a by product to fabricate precast building blocks.

Keyword : Light Concrete, Properties, Polystyrene Granulars

Some Problems Of The Main Canal In North Jazira Irrigation Project &The Curves Which Are Used In It

Huda H. Bader; Mohammed A. AL MALLAH

Al-Rafidain Engineering Journal (AREJ), 2006, Volume 14, Issue 2, Pages 48-57
DOI: 10.33899/rengj.2006.46618

A good alignment of irrigation canal means efficient transport of irrigation water,
least cost of construction and maintenance. In this study we determined some
imported sections of the main canal in north Jazira irrigation project where
sediment & collapse which happened in the banks and the bed of the main canal.
We suggest some methods to stopped or treated them.
Keyword (Alignment Of Canal _ Curve _ North Jazira Irrigation Project)

Changing the Architectural Elements and it’s Effect on Mosul Architecture

Hafid Abid Yahya Al-Hiali; Dr. Abdullah Y. Al-Tayib

Al-Rafidain Engineering Journal (AREJ), 2006, Volume 14, Issue 1, Pages 1-13
DOI: 10.33899/rengj.2006.46285

The research problem has been determined through the necessity of the
architectural elements and determining their relations to one anther with the aim of
studying the shifts that have been taken place in Mosul architecture. The research
methodology encompasses the application of this frame to buildings that date back to
the various stages of architectural change. Consequently, to find out change that have
occurred in Mosul architecture elements and the diachronic relations which testify to
either continuity or change in it. The research also embraces the method of collecting
data on building samples. These include (20) building samples chosen according to
objective criteria. Then, a case study on these samples has been applied using a special
formula. In Consequence, results relating to the research hypothesis have testified,
together with the finding, significant variance between the architectural phases through
the changes that have taken place in the architectural elements.
Keyword: Mosul architecture, architectural stages and change.