With the development of computer architecture and its technologies in recent years, applications like e-commerce, e-government, e-governance and e-finance are widely used, and they act as active research areas. In addition, in order to increase the quality and quantity of the ordinary everyday transactions, it is desired to migrate from the paper-based environment to a digital-based computerized environment. Such migration increases efficiency, saves time, eliminates paperwork, increases safety and reduces the cost in an organization. Digital signatures are playing an essential role in many electronic and automatic based systems and facilitate this migration. The digital signatures are used to provide many services and s
... Show MoreIn this modern Internet era and the transition to IPv6, routing protocols must adjust to assist this transformation. RIPng, EIGRPv6 and OSPFv3 are the dominant IPv6 IGRP (Interior Gateway Routing Protocols). Selecting the best routing protocol among the available is a critical task, which depends upon the network requirement and performance parameters of different real time applications. The primary motivation of this paper is to estimate the performance of these protocols in real time applications. The evaluation is based on a number of criteria including: network convergence duration, Http Page Response Time, DB Query Response Time, IPv6 traffic dropped, video packet delay variation and video packet end to end de
... Show Moreتُعَد اتصالات الموجات المليمترية (mmWave) حلولاً مبتكرة لشبكات الجيل الخامس وما بعدها، نظرًا للتطورات السريعة في عالم الاتصالات. تقدم هذه الورقة شبكة وصول راديوي سحابي غير متجانسة (HC-RAN) تستخدم نطاقات تردد الموجات المليمترية والأقل من 6 جيجاهرتز لتلبية هذه الحاجة. يتم تقديم ارتباطات المستخدمين بوحدات رؤوس الراديو البعيدة (RRHs) للتخفيف من التداخل وتعظيم إنتاجية الشبكة باستخدام خوارزمية (Q-Learning). توفر عمليات النشر
... Show MoreConcrete-filled steel tubes (CFST) are structural members consisting of hollow steel tubes filled with concrete. Both steel and concrete work together to provide several advantages. The concrete increases the steel tube's resistance against local buckling while the steel tube confines the concrete, which increases its compressive strength. The use of CFST beams increased in high buildings due to their great mechanical properties. The researchers were interested in CFST beams because of their great ductility, stiffness, strength, and flexural capacity when compared to hollow steel beams. The properties of CFST beams were enhanced in several ways, for example, by using carbon fiber reinforced polymer (CFRP) wrapping, addin
... Show MorePlastic waste materials are constantly increasing around the world as a result of the growing human consumption of these materials day by day, with no actual solutions to get rid of them without causing harm to the environment or the health of living organisms. Therefore, in this research, two types of plastic waste materials are utilized to enhance soft clay soil: polyethylene terephthalate (PET) and nylon (N), in percentages of (1, 1.5, 2, 2.5)% from dry soil weight, to enhance the clay soft soils properties, which are characterized by their excessive compressibility, low bearing capacity, and low shear strength. This study is carried out by conducting laboratory tests before and after the addition. These tests include
... Show Moreيعتمد تطبيق روبوت التوازن الذاتي ذو العجلتين على مهام العالم الحقيقي بشكل حاسم على قدرته على رفض الاضطرابات بشكل فعال. الهدف هو تصميم وحدتي تحكم نشطتين لرفض الإزعاج (ADRCs) لزاوية الجسم والإزاحة، على التوالي، لنظام روبوت ذاتي التوازن ذو عجلتين، والذي يصعب التحكم فيه بسبب الاقتران القوي، وعدم الخطية، وعدم اليقين في المعلمات. استنادًا إلى ديناميكيات النظام، تم تصميم إطار التحكم ADRC لتقدير وتعويض أخطاء النمذجة و
... Show MoreIn this paper, a proposed method based on real-coded genetic algorithm is presented and applied to solve multiple load flow solution problem. Genetic algorithm is a kind of stochastic search algorithm based on the mechanics of natural selection and natural genetics. They combine the concepts of survival of the fittest with genetic operators such as selection, crossover and mutation abstracted from nature to form a surprisingly robust mechanism that has been successfully applied to solve a variety of search and optimization problems. Elitist method is also used in this research, and blending models are implemented for crossover operator. In the proposed work, five busbars typical test system and 362-bus Iraqi National Grid are used to dem
... Show MoreThe main objective of this work is to propose a new routing protocol for wireless sensor network employed to serve IoT systems. The routing protocol has to adapt with different requirements in order to enhance the performance of IoT applications. The link quality, node depth and energy are used as metrics to make routing decisions. Comparison with other protocols is essential to show the improvements achieved by this work, thus protocols designed to serve the same purpose such as AODV, REL and LABILE are chosen to compare the proposed routing protocol with. To add integrative and holistic, some of important features are added and tested such as actuating and mobility. These features are greatly required by some of IoT applications and im
... Show MoreAsSanna'f Marsh is one of the southern Iraqi Marshes. It is considered as a seasonal marsh. During rainy season, the marsh feeders start to fill the nearly empty region of the marsh and the water levels start to increase gradually. After the water level reaches a specific value, it starts to flow toward Al Huwayza Marsh. Studies on the hydrological properties of AsSanna'f Marsh are rare and there is a lack of hydrological data of AsSanna’f Marsh feeders. Generally, this paper was prepared to predict missing hydrological data, a procedure was developed and applied for this purpose, and to be used with the available hydrological and topographical data for modeling and analysis the hydrological properties of AsSanna’f Marsh. The topogra
... Show MoreUp to date, in many foundation design problems (especially for piles foundation), the shear strength (skin friction) between soil and construction materials of the foundation was usually estimated or correlated without any direct methods for measurement.
The modern trend is to establish skin friction coefficients through laboratory experiments in which the factors influencing the results may be controlled quantitatively.
In this study strain controlled Direct Shear Tests were performed using shear to simulate the shear behavior area between concrete (foundation materials) and undisturbed over consolidated silty clay, to determine the shear strength of soil – foundation interface, considering the following variables : (1) Concrete
The aim of this paper is to integrate mobile phones into LANs by connecting the two parties and providing the mobile with a transparent access to the services and resources hosted by the LAN. Quick assessment of the typical related approaches for accessing LAN (like WLAN and Bluetooth BNEP) shows that they are inappropriate for mobile phones. The paper further inspects the LAN access approach based on Bluetooth PAN Profile and marking up its potential drawbacks. A modified approach is proposed and implemented by altering the access nature or model from peer-to-peer communication to a client/server service providing, and switching from BNEP to RFCOMM protocol.
Experimental research was carried out to investigate the performance of CFRP wrapping jackets used for retrofitting twelve square reinforced concrete (CR) column specimens damaged by exposure to fire flame, at different temperatures of 300, 500 and 700ºC, except for two specimens that were not burned. The specimens were then loaded axially till failure after gradual or sudden cooling. The specimens were divided into two groups containing two main reinforcement ratios, ρ= 0.0314 and ρ= 0.0542. This was followed by the retrofitting procedure that included wrapping all the specimens with two layers of CFRP fabric sheets. The test results of the retrofitted specimens showed that the fire damaged RC
... Show MoreThe research focuses on examining the level of harmony in the formal characteristics among the elements of the traditional Baghdad alley, from individual components to the entire area. Numerous studies have highlighted the unity and cohesion in the urban structures of traditional Arab urban environments, including Baghdad alleys, despite the diversity of the urban landscape. The study's theoretical aspect focuses on the visual features of the traditional urban environment, emphasizing the concept of diversity within unity. This is explored through specialized studies in the field. The applied part of the study involves using fractal geometry tools, specifically the box-counting method, to measure the degree of harmony an
... Show MoreThe degradation performance of aqueous solution of pesticide Alachlor has been studied at solar pilot scale plant in two photocatalytic systems: homogeneous photocatalysis by photo-Fenton and heterogeneous photocatalysis with titanium dioxide. The pilot scale system included of compound parabolic collectors specially designed for solar photocatalytic applications, and installed at University of Baghdad, Department of Environmental Engineering back yard. The influence of different concentrations, H2O2 (200-2400 mg/l), Fe+2(5- 30 mg/l) and TiO2 (100-500 mg/l) and their relationship with the degradation efficiency were studied.
The COD removal efficienc
... Show MoreOver the past few decades, the surveying fieldworks were usually carried out based on classical positioning methods for establishing horizontal and vertical geodetic networks. However, these conventional positioning techniques have many drawbacks such as time-consuming, too costly, and require massive effort. Thus, the Global Navigation Satellite System (GNSS) has been invented to fulfill the quickness, increase the accuracy, and overcome all the difficulties inherent in almost every surveying fieldwork. This research assesses the accuracy of local geodetic networks using different Global Navigation Satellite System (GNSS) techniques, such as Static, Precise Point Positioning, Post Processing Kinematic, Session method, a
... Show MoreThis paper presents a new design of a nonlinear multi-input multi-output PID neural controller of the active brake steering force and the active front steering angle for a 2-DOF vehicle model based on modified Elman recurrent neural. The goal of this work is to achieve the stability and to improve the vehicle dynamic’s performance through achieving the desired yaw rate and reducing the lateral velocity of the vehicle in a minimum time period for preventing the vehicle from slipping out the road curvature by using two active control actions: the front steering angle and the brake steering force. Bacterial forging optimization algorithm is used to adjust the parameters weights of the proposed controller. Simulation resul
... Show MoreAeroelastic flutter in aircraft mechanisms is unavoidable, essentially in the wing and control surface. In this work a three degree-of-freedom aeroelastic wing section with trailing edge flap is modeled numerically and theoretically. FLUENT code based on the steady finite volume is used for the prediction of the steady aerodynamic characteristics (lift, drag, pitching moment, velocity, and pressure distribution) as well as the Duhamel formulation is used to model the aerodynamic loads theoretically. The system response (pitch, flap pitch and plunge) was determined by integration the governing equations using MATLAB with a standard Runge–Kutta algorithm in conjunction with Henon’s method. The results are compared with
... Show MoreBitumen aging contributes to main pavement distress due to the changes in rheological, chemical, and physical characteristics of bitumen. Mainly, aging process can be divided into two categories, the first category namely short-term aging takes place during the heating up of bitumen and aggregate, mixing, transportation, laying down, and compaction. While the second category of aging takes place during the service life of pavement which is denoted as long-term aging. Consequently, researchers’ focus is to simulate bitumen aging in the lab by developing lab-accelerated methods to simulate the process of bitumen aging and studying the rate of change before and after aging. This article reviews these methods and compares
... Show MoreNumerical analysis of the cooling process of hot water discharge from a steam power plant into a river has been carried out in the present study. A mathematical model describing the flow field and temperature distribution induced in the river as a result of the cooling process is made based upon the assumptions of steady state, two-dimensional, turbulent flow, in the horizontal plane. The governing equations are the continuity, the momentum, the (К-ε) turbulence model and the energy equation. A proper initial and boundary condition are specified to be used in the solution of the governing equations. A numerical solution of the governing equations is made by using the control volume approach, with non-staggered grid technique and modifi
... Show MoreScrap metal export is currently one of the few thriving industries in Iraq. Looters and legitimate operators are together effectively demolishing many of the old industrial facilities in order to retrieve the metal contained in buildings, processes and storage equipments and vehicles. The mixing of civilian and military scrapping operations such as that occurring at Ouireej is exacerbating the problem. The situation is particularly difficult for Iraq, given the rapid growth of the scrap industry and the lack of security. In view of the current difficulties, the focus was on practical short to medium term improvements such as controlling access to sites, land use zoning, licensing and export controls. The wholesale reform of the scrap met
... Show MoreRegression analysis models are adopted by using SPSS program to predict the 28-day compressive strength as dependent variable and the accelerated compressive strength as independent variable. Three accelerated curing method was adopted, warm water (35ºC) and autogenous according to ASTM C C684-99 and the British method (55ºC) according to BS1881: Part 112:1983. The experimental concrete mix design was according to ACI 211.1. Twenty eight concrete mixes with slump rang (25-50) mm and (75-100)mm for rounded and crushed coarse aggregate with cement content (585, 512, 455, 410, 372 and 341)Kg/m3.
The experimental results showed that the acc
... Show MoreThe rotor dynamics generally deals with vibration of rotating structures. For designing rotors of a high speeds, basically its important to take into account the rotor dynamics characteristics. The modeling features for rotor and bearings support flexibility are described in this paper, by taking these characteristics of rotor dynamics features into standard Finite Element Approach (FEA) model. Transient and harmonic analysis procedures have been found by ANSYS, the idea has been presented to deal with critical speed calculation. This papers shows how elements BEAM188 and COMBI214 are used to represent the shaft and bearings, the dynamic stiffness and damping coefficients of journal bearings as a matrices have been found
... Show MoreThe constructed building in the urban area is subject to wind characteristics due to the influence of surrounding buildings. The residential complexes currently being built in Iraq represent a case study for the subject of this research. Therefore, the objective of this study is to identify the interference effect because of adjacent buildings effects on the mid-rise building. The speed and pressure of the wind have been numerically simulated as well as wind load has been simulated by using a virtual wind tunnel which is available in Autodesk Robot Structural Analysis, RSA, software. Two identical adjacent buildings have been simulated and many coefficients were included in this study such as the spacing, directionality,
... Show MoreRoof in the Iraqi houses normally flattening by a concrete panel. This concrete panel has poor thermal properties. The usage of materials with low thermal conductivity and high specific heat gives a good improvements to the thermal properties of the concrete panel, thus, the indoor room temperature improves. A Mathcad program based on a mathematical model employing complex Fourier series built for a single room building. The model input data are the ambient temperature, solar radiation, and sol-air temperature, which have been treated as a periodic function of time. While, the room construction is constant due to their materials made of it, except the roof properties are taken as a variable generated practically from the
... Show MoreImage quality and geometric accuracy of SPOT data are essential elements in cartographi: applications. The evaluation of geometric accuracy of SPOT data is carried out by analysis and quantification of the errors in geometric correction. For this purpose, many programs are designed to correct the image geometrically (polynomial transformation) and to calculate the root mea 1 square error (RMSE) by the standard method.
The standard method of calculating the RMSE is shown to be capable of providing accurate estimates of geometric error when a modest number of control points is available (between 10-15 points). This method also provides an indication of the effects of choosing differer t polynomial orders.
Semi-analytical solution for the resistance of the flow and convective heat and mass transfer over the surface of ellipsoidal bubble and a drop were obtained. The fluid flow solution utilized the viscous dissipation and the heat transfer solution was based on the integral method. New relations for the drag force and the convective heat and mass transfer coefficients were derived and compared with the available theoretical solutions and experimental correlations. The range of Reynoks number was from I to 100 and Weber number from 0 to 3.23.
In this paper, a method is proposed to increase the compression ratio for the color images by
dividing the image into non-overlapping blocks and applying different compression ratio for these
blocks depending on the importance information of the block. In the region that contain important
information the compression ratio is reduced to prevent loss of the information, while in the
smoothness region which has not important information, high compression ratio is used .The
proposed method shows better results when compared with classical methods(wavelet and DCT).
An improved Metal Solar Wall (MSW) with integrated thermal energy storage is presented in this research. The proposed MSW makes use of two, combined, enhanced heat transfer methods. One of the methods is characterized by filling the tested ducts with a commercially available copper Wired Inserts (WI), while the other one uses dimpled or sinusoidal shaped duct walls instead of plane walls. Ducts having square or semi-circular cross sectional areas are tested in this work.
A developed numerical model for simulating the transported thermal energy in MSW is solved by finite difference method. The model is described by system of three governing energy equations. An experimental test rig has been built and six new duct configurations have b
A numerical investigation has been performed to study the effect of eccentricity on unsteady state, laminar aiding mixed convection in a horizontal concentric and eccentric cylindrical annulus. The outer cylinder was kept at a constant temperature
while the inner cylinder was heated with constant heat flux. The study involved numerical solution of transient momentum (Navier-Stokes) and energy equation using finite difference method (FDM), where the body fitted coordinate system (BFC) was
used to generate the grid mesh for computational plane. The governing equations were transformed to the vorticity-stream function formula as for momentum equations and to the temperature and stream function for energy equation.
A computer progra
In recent decades, tremendous success has been achieved in the advancement of chemical admixtures for Portland cement concrete. Most efforts have concentrated on improving the properties of concrete and studying the factors that influence on these properties. Since the compressive strength is considered a valuable property and is invariably a vital element of the structural design, especially high early strength development which can be provide more benefits in concrete production, such as reducing construction time and labor and saving the formwork and energy. As a matter of fact, it is influenced as a most properties of concrete by several factors including water-cement ratio, cement type and curing methods employed.
Because of acce