Orthogonal Frequency Division Multiplexing (OFDM) is one of recent years multicarrier modulation used in order to combat the Inter Symbol Interference (ISI) introduced by frequency selective mobile radio channel. The circular extension of the data symbol, commonly referred to as cyclic prefix is one of the key elements in an OFDM transmission scheme. This paper study The influence of the cyclic prefix duration on the BER performance of an OFDM-VCPL (Orthogonal frequency division multiplexing - Variable Cyclic Prefix Length) system and the conventional OFDM system with frame 64-QAM modulation is evaluated by means of computer simulation in a multipath fading channel. The adaptation of CP is done with respect to the delay spread estimation

Activated carbon has been used as an adsorbent in this work to remove mercury from aqueous solutions. The aim of the work is to test how best activated carbon can be used as an adsorbent for mercury. Equilibrium isotherms, both, Dubinin-Redushkevich, and Temkin have been test. The batch experiments were conducted at room temperature (30oC) and at the normal pH (7.0±0.1) of the solution. HYBRID fraction error function analysis shows that the best-fit for the adsorption equilibrium data is represented by (D-R) model rather than Temkin model. Its found that the correction factor (R2) for (D-R) is 0.9928 while for Temkin model is 0.942, also the HYBRID fractional error was conducted for the both models and (D-R) model give minimum value of

Because of practical importance of protecting industrial equipments from galvanic corrosion,
the need arises to analyze the effects of variables, such as temperature, velocity, and area fraction of  metals on galvanic corrosion in systems under mass transfer control as in seawater (pH=7). For these reasons the galvanic corrosion of Fe-Zn is analyzed to study the influence of Reynolds number, temperature, and area fraction on the galvanic corrosion rates and galvanic corrosion potential under mass transfer control. It is found that galvanic corrosion rate of more active metal (Zn) is increased with Reynolds number while the corrosion rate of more noble metal (Fe) is slightly increased with Re depending on the galvanic potential tha

A new application of a combined solvent extraction and two-phase biodegradation processes using two-liquid phase partitioning bioreactor (TLPPB) technique was proposed and developed to enhance the cleanup of high concentration of crude oil from aqueous phase using acclimated mixed culture in an anaerobic environment. Silicone oil was used as the organic extractive phase for being a water-immiscible, biocompatible and non-biodegradable. Acclimation, cell growth of mixed cultures, and biodegradation of crude oil in aqueous samples were experimentally studied at 30±2ºC. Anaerobic biodegradation of crude oil was examined at four different initial concentrations of crude oil including 500, 1000, 2000, and 5000 mg/L. Complete removal of crud

Tests were performed on asphalt concrete specimens with (101.6 mm in diameter and 101.6 mm in height), and the results were implemented for calculating permanent deformation and resilient modulus under repeated compressive stress with different levels of stresses (0.068, 0.138 and 0.206) MPa at 40 ºC. Two types of additives namely (carbon black-asphalt) and (SBR-asphalt) were tried as rejuvenators with three percentages of (0.5, 1 and 1.5) % by weight of asphalt cement along with two ratios of AC (1 and 2) % have been implemented as rejuvenator and blended with the reclaimed asphalt concrete. Aged materials were obtained from the site. 100% Reclaimed Asphalt Pavement material from the reclaimed mixture is implemented. A

In order to determine The Identity of Future Cities, the architecture does not provide us with one of the most basic needs (shelter), but also tangible evidence of the past and present as part of the communication, and best is an indicator of the future. Most of the  narratives of the transformations of urban in twenty one century agreed that the city changed from an industrial society, the dominant over the previous century, to a pattern dominated by knowledge,information and communications, especially those that are remote and penetrated into the urban fabric, which produced the perceptions about the nature of identity, urban cities of the future, focusing Alternative research efforts of the city's future on the role of modern communi

A two time step stochastic multi-variables multi-sites hydrological data forecasting model was developed and verified using a case study. The philosophy of this model is to use the cross-variables correlations, cross-sites correlations and the two steps time lag correlations simultaneously, for estimating the parameters of the model which then are modified using the mutation process of the genetic algorithm optimization model. The objective function that to be minimized is the Akiake test value. The case study is of four variables and three sites. The variables are the monthly air temperature, humidity, precipitation, and evaporation; the sites are Sulaimania, Chwarta, and Penjwin, which are located north Iraq. The model performance was

In this paper, wireless network is planned; the network is predicated on the IEEE 802.16e standardization by WIMAX. The targets of this paper are coverage maximizing, service and low operational fees. WIMAX is planning through three approaches. In approach one; the WIMAX network coverage is major for extension of cell coverage, the best sites (with Band Width (BW) of 5MHz, 20MHZ per sector and four sectors per each cell). In approach two, Interference analysis in CNIR mode. In approach three of the planning, Quality of Services (QoS) is tested and evaluated. ATDI ICS software (Interference Cancellation System) using to perform styling. it shows results in planning area covered 90.49% of the Baghdad City and used 1000 mob

In this work, strains and dynamic crack growth were studied and analyzed in thin flat plate with a surface crack at the center, subjected to cycling low velocity impact loading for two types of aluminum plates (2024, 6061). Experimental and numerical methods were implemented to achieve this research. Numerical analysis using program (ANSYS11-APDL) based on finite element method used to analysis the strains with respect to time at crack tip and then find the velocity of the crack growth under cycling impact loading. In the experimental work, a rig was designed and manufactured to applying the cycling impact loading on the cracked specimens. The grid points was screened in front of the crack tip to measure the elastic-plas

This paper describes an experimental study on the performance of sulfamic acid and citric acid in scale removal of Dura refinery heat exchange piping systems. Experiments were carried out using sulfamic acid and citric acid inhibited by hexamine as cleaning solutions at different time, temperature and concentrations. A dynamic flow system was designed for this state. A scaled copper alloy pipes from the main hot water lines (heat exchanger) was used. Hexamine was used as corrosion inhibitor.The research involved a study of effect of the time ,temperature and acid concentration of each acid on the scale removal, and a comparison of the performance of the two used acids were investigated.

A new model for the non-linear propeller-pendulum system is derived in this study. The model takes into consideration the effects of external disturbances and the properties of the pendulum elements. Two systems with PID controllers are simulated. In the first system, Simulink is used to implement the system and tune the PID parameters. In the second system, a MATLAB script is used to simulate the system and tune the PID parameters. The scrip uses the Runge-Kutta method for solving the system’s equation and uses particle swarm optimization (PSO) to tune the parameters. Further, both systems were investigated under two disturbance conditions. The performance of these systems is evaluated based on comparing the settling

This paper delineates the parallelisation of a computer vision system. It presents the system proposal and the relevant design phases of a laboratory based model. This model involves special purpose hardware implementing the early stages of processing with very high data rate. It Incorporates facilities enabling the user to capture, retain, retrieve, compare, and analyse video images. The output of this hardware is to be processed by a software running in a parallel processor. The latter is a VMEbus-based multiprocessing machine accommodating the system hardware and ensures for better flexibility. It also participates in a reasonable distribution of the systern processing power. The kernel philosophy here depends on the concept of modula

This search has introduced the techniques of multi-wavelet transform and neural network for recognition 3-D object from 2-D image using patches. The proposed techniques were tested on database of different patches features and the high energy subband of discrete multi-wavelet transform DMWT (gp) of the patches. The test set has two groups, group (1) which contains images, their (gp) patches and patches features of the same images as a part of that in the data set beside other images, (gp) patches and features, and group (2) which contains the (gp) patches and patches features the same as a part of that in the database but after modification such as rotation, scaling and translation. Recognition by back propagation (BP) neural network as

The important way to obtain lightweight concrete with compressive strength, density, and thermal insulation properties that differ from normal concrete was by adding materials with cementitious properties to the concrete mix instead of cement or using lightweight aggregate. In most cases, the compressive strength of the lightweight concrete produced was less than that of normal concrete. The aim of this research was to conduct three main objectives. The first objective is to produce lightweight concrete with good compressive strength compared to the same type of concrete by adding chemical additives (Super-Plasticizer S.P and Carbon Powder C.P) to the lightweight concrete mix. The second objective is to recycle the resid

In this paper, isobutane (R-600a) is used as a suitable substitute for (R-134a) when changing the length of capillary tube. And the experimental data on capillary tube are obtained under different conditions such as (subcooling and ambient temperatures) on domestic refrigerator (9ft3 size), this data shows that (R-600a) a suitable substitute for (R134a) .The test presented a model for a steady state, two-phase flow in capillary tube for vapour compression system .The numerical model depends on conservation equations (mass, energy and momentum) as wall as the equation of state for refrigerant. The solution methodology was implemented by using finite difference techniques. The system results indicate that it is possible to change the refri

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 velocit

The purpose of this research presents the research results obtained from a numerical simulation using the ABAQUS/CAE version 2019 finite element software. This study tested the shear behavior of T-beams made of reinforced concrete (RC). The structure is reinforced with a carbon fiber reinforced polymer (CFRP) bar embedded through a section (ETS). The numerical validation approach implicated using numerical analysis on the experimental data collected from twelve reinforced concrete (RC) T-beams divide into two groups each group include reference beam, the field of numerical analysis was expanded to encompass the examination of many aspects, such as the impact of the diameter of CFRP bars. The main objective of this projec

Information about soil consolidation is essential in geotechnical design. Because of the time and expense involved in performing consolidation tests, equations are required to estimate compression index from soil index properties. Although many empirical equations concerning soil properties have been proposed, such equations may not be appropriate for local situations. The aim of this study is to investigate the consolidation and physical properties of the cohesive soil. Artificial Neural Network (ANN) has been adapted in this investigation to predict the compression index and compression ratio using basic index properties. One hundred and ninety five consolidation results for soils tested at different construction sites

The present study develops an artificial neural network (ANN) to model an analysis and a simulation of the correlation between the average corrosion rate carbon steel and the effective parameter Reynolds number (Re), water concentration (Wc) % temperature (T o) with constant of PH 7 . The water, produced fom oil in Kirkuk oil field in Iraq from well no. k184-Depth2200ft., has been used as a corrosive media and specimen area (400 mm2) for the materials that were used as low carbon steel pipe. The pipes are supplied by Doura Refinery . The used flow system is all made of Q.V.F glass, and the circulation of the two –phase (liquid – liquid ) is affected using a Q.V.F pump .The input parameters of the model consists of Reynolds number , w

The issue of noise transmission between residential units in high-rise buildings poses a significant challenge to privacy and auditory comfort, especially amid increasing urban expansion and population density. This study aims to address this problem by evaluating sound insulation strategies in high-rise residential units and assessing their alignment with international standards within local contexts. Six global residential projects were analyzed based on their adoption of advanced acoustic insulation solutions. The methodology involved examining key design elements such as the spatial distribution between quiet and noisy areas, and the use of insulation materials and techniques for walls, floors, ceilings, doors, and w

Grayscale images are extensively used due to their simplicity and cheapness in storage and transmission compared to color one of RGB base. It can also be considered a solution for color-blind people to ensure a better view of things and reading. However, unfortunately, it is still quite overburdened with redundancy(s) in which the data compression exploits them efficiently depending on the type and way of redundancy removal. This work introduces a hybrid compression system to compress grayscale images using the adaptive pixel-based technique (PBT) of optimized modeling base, with incorporated Minimize Matrix Size Algorithm (MMSA) of three digits values (C321) to encode the residual compactly along the need to overhead in

Many problems are facing the installation of piles group in laboratory testing and the errors in results of load and settlement are measured experimentally may be happened due to select inadequate method of installation of piles group. There are three main methods of installation in-flight, pre-jacking and hammering methods. In order to find the correction factor between these methods the laboratory model tests were conducted on small-scale models. The parameters studied were the methods of installation (in-flight, pre-jacking and hammering method), the number of piles and in sandy soil in loose state. The results of experimental work show that the increase in the number of piles value led to increase in load carrying ca

 The permeability determination in the reservoirs that are anisotropic and heterogeneous is a complicated problem due to the limited number of wells that contain core samples and well test data. This paper presents hydraulic flow units and flow zone indicator for predicting permeability of rock mass from core for Nahr-Umr reservoir/ Subba field. The Permeability measurement is better found in the laboratory work on the cored rock that taken from the formation. Nahr-Umr Formation is the main lower cretaceous sandstone reservoir in southern of Iraq. This formation is made up mainly of sandstone. Nahr-Umr formation was deposited on a gradually rising basin floor. The digenesis of Nahr-Umr sediments is very important du

In this work a high-speed turbopumps of (22000 rpm) rotational speed, which are oxidizer and fuel turbopumps, are designed. The design requirement for mass flow rate and outlet pressure are (12.5 kg/s) and (113×10 Pa) respectively for the oxidizer turbopump, and (3.5 kg/s) and (95x10 Pa) respectively for the fuel turbopump. The design work of centrifugal pump is divided into impeller and volute design works. The impeller design work is performed by the streamline curvature and quasi-orthogonal technique based on hub-to-shroud mean stream surface between two blades with assistance of experimental design coefficients and relations for first prediction. The volute is designed by using the method of constant angular momentum, where in this

Global Navigation Satellite Systems (GNSS) have become an integral part of wide range of applications. One of these applications of GNSS is implementation of the cellular phone to locate the position of users and this technology has been employed in social media applications. Moreover, GNSS have been effectively employed in transportation, GIS, mobile satellite communications, and etc. On the other hand, the geomatics sciences use the GNSS for many practical and scientific applications such as surveying and mapping and monitoring, etc.

In this study, the GNSS raw data of ISER CORS, which is located in the North of Iraq, are processed and analyzed to build up coordinate time series for the purpose of detection the

Recently, implantable antennas have gained prominence in biomedical research owing to their compact design and efficient performance and extensive potential in biomedical and wireless communication applications. One such application is in the biomedical field, where the designed system must function within human body tissues and interact with an external device. To implement this communication framework, both advanced software and proper hardware design are essential. The antenna that is designed for biomedical applications must fulfill several requirements including energy efficiency, compact size, and multi-band operations. Therefore, designing an antenna with large bandwidth, multiband capability, circular polarizatio

This investigation deals with the effect of weir height, liquid and gas flow rate on tray efficiency.
The tests were carried out on a single pass cross flow tray of air-water system of 0.3 m diameter for clear
liquid height over sieve tray with weir height 3, 4 and 5 cm.
Point efficiency values were found to be in the same range for different weir height, but it
improves slightly with weir height. And the average values of point efficiency were 83 % for 3 cm weir
height, 85 % for 4 cm weir height and 89 % for 5 cm weir height. While, point efficiency of 90 % was obtained for 5 cm weir height and liquid flow rate ranging between 5.8 to 7.32 m3/s. In the range of clear liquid height over hole diameter ( hL/dH) between 2 to 1

Shell foundations are generally found to be economic under conditions of heavy loads and weak soils as small amount of reinforcement is needed due to occurrence of compressive stresses in most parts of the foundation. Depending upon their size, conical shells can serve as footings for columns while inverted domes shells can serve as rafts for tanks supported on a circular row of columns. This paper describes 3-D finite element models, the eight nodes degenerated shell and the twenty nodes brick elements which are used herein. The models which may be adopted in the material nonlinear analysis of reinforced concrete shell foundations are described briefly in this paper. The present study results give good agreement compared with available

This work is concerned with designing two types of controllers, a PID and a Fuzzy PID, to be used
for flying and stabilizing a quadcopter. The designed controllers have been tuned, tested, and
compared using two performance indices which are the Integral Square Error (ISE) and the Integral
Absolute Error (IAE), and also some response characteristics like the rise time, overshoot, settling
time, and the steady state error. To try and test the controllers, a quadcopter mathematical model has
been developed. The model concentrated on the rotational dynamics of the quadcopter, i.e. the roll,
pitch, and yaw variables. The work has been simulated with “MATLAB”. To make testing the
simulated model and the controllers m

The main object of this work is to study the effect of coarse aggregate/cement ratio (A/C) on the property of no fine concrete. In this work, three ratio of A/C were used (6, 9 and 12 by weight).The cement content is maintained constant (125kg/m3) while the w/c ratio ranges from (0.39 to 0.55 by weight). Tests are carried out on hardened concrete to investigate the effect of coarse aggregate/cement ratio on the compressive strength, absorption%, density, porosity%, ultrasonic pulse velocity, acoustic impedance of mixes.
The results showed that increasing the percentage of A/C ratio by weight from 6 to 12 for the used mixes reduces the compressive strength, ultrasonic pulse velocity and acoustic impedance, on the other hand the porosit