In this paper possible improvements in the performance of adaptive Linear Equalizer (LE) and Decision Feed Back Equalizer (DFE) are reported. A modified Least Mean Square (LMS) algorithm incorporating a recursively adjusted adaptation step size based on rough estimate of the performance surface gradient square is proposed. The first
proposed algorithm was called Adjusted Step Size LMS (ASSLMS) which used single adjusted step size for all weight coefficients. The second proposed algorithm was called Distributed Step Size LMS algorithm (DSSLMS). This algorithm (i.e. DSSLMS) will distribute the resultant variable step size in an exponential form among all weights of the
adaptive filter such that each weight coefficient has its own

Twisted tape insertion in the smooth plain tube is one of the types of passive methods that are used to enhance heat transfer. Swirl fluid flow inside the tube and related heat transfer characteristics are very complex. ANSYS FLUENT (V 16.1) and ASPEN industrial program are used in analyzing this technique for enhancement heat transfer. A circular plain tube has length L=8534mm and 17 mm inner diameter with a twisted tape of twist ratio of y = (H/D) = (150/17) =8.8 along the plain tube were considered for this study. Eight Reynolds numbers (Re) of 784, 1000, 2000, 3000, 4000, 5000, 6000 and 7000 are used to analyze the response of thermal performance. Crude oil API 28 exit temperature, film heat transfer coefficient, Nus

Treatment of a high strength acidic industrial wastewater was attempted by activated carbon
adsorption to evaluate the feasibility of yielding effluents of reusable qualities. The experimental
methods which were employed in this investigation included batch and column studies. The
former was used to evaluate the rate and equilibrium of carbon adsorption, while the latter was
used to determine treatment efficiencies and performance characteristics. Fixed bed and expanded
bed adsorbers were constructed in the column studies. In this study, the adsorption behavior of acetic acid onto activated carbon was examined as a function of the concentration of the adsorbate, contact time and adsorbent dosage. The adsorption data was mo

The heat and mass transfer coefficients of the indirect contact closed circuit cooling tower, ICCCCT, were investigated experimentally. Different experiments were conducted involving the controlling parameters such as air velocity, spray water to air mass flow rate ratio, spray water flow rate, ambient air wet bulb temperature and the provided heat load to investigate their effects on the performance of the ICCCCT. Also the effect of using packing on the performance of the ICCCCT was investigated. It was noticed that these parameters affect the tower performance and the use of packing materials is a good approach to enhance the performance for different operational conditions. Correlations for mass and heat transfer coefficients are pres

Recently, Social Sustainability has gained significant value as it was considered by the late studies as a principal dimension along with the environmental and economic sustainability. And because of, on the other hand, the significant social role of the school for forming the student’s personality, this research is an appeal for rehabilitating and promoting Iraqi Schools according the issue of social sustainability.As there is no evaluation for the Iraqi Schools, the research is dedicated to this problem, aiming to carry out the stated evaluation and define the design treatments needed for the rehabilitation process. To achieve this goal, a theoretical background for the concept of social sustainability, its criteria, the school and i

In this research, the removal of cadmium (Cd) from simulated wastewater was investigated by using a fixed bed bio-electrochemical reactor. The effects of the main controlling factors on the performance of the removal process such as applied cell voltage, initial Cd concentration, pH of the catholyte, and the mesh number of the cathode were investigated. The results showed that the applied cell voltage had the main impact on the removal efficiency of cadmium where increasing the applied voltage led to higher removal efficiency. Meanwhile increasing the applied voltage was found to be given lower current efficiency and higher energy consumption.  No significant effect of initial Cd concentration on the removal efficie

A numerical investigation of the non-cavitating and cavitating performance of a three-blade pump inducer under nominal and off-design operating conditions is presented. Three different simulated hydrofoils; a flat plate, “NACA0004", and "Clark-Y-6%" has been selected to represent the profile of the inducer blade. A 2D, steady, incompressible, turbulent, and isothermal flow field between the inducer blades is simulated using the FVM. The "Interface Tracking" model is selected to predict the cavity profile of the attached cavitation and the cavitating performance drop. For each blade profile, the influence of solidity in the range of (1.8 to 3.0) and blade angle in the range of (20° to 35°) on the inducer performance is studied. Compar

A numerical investigation was conducted to study the effect of simulated ice accreted on airfoil
aerodynamics performance. The simulated ice shapes were tested on NACA 0012 airfoil wing at
different Mach numbers. The study includes the one of the famous types of ice accreted on the
airfoils called the rime ice.
The calculation of ice droplet trajectories was performed by solving the trajectories governing equations of the droplet using FVM. A numerical model based on staggered FVM is built up to solve the governing equations of a body fitted grid, trajectories equation, continuity equation and momentum equation using FORTRAN 97. The turbulence model of (k-ε) has been adopted in the programming to evaluate the turbulence effe

يتناول البحث موضوع إيجاد أبنية كفوءة مناخياً تتميز أغلفتها البنائية بديناميكية عالية تمكنها من التفاعل والتكامل بتغير المواسم في منطقتنا الحارة - الجافة، إذ أن إستيراد الأفكار المعمارية وظهور التقنيات الجديدة أفرز توجهاً فكرياً وعمرانياً يتعارض وأدنى خصائص هذه المنطقة بيئياً وعمرانياً، ومن ثم نشوء عمارة غير منتمية للواقع البيئي المحيط بها فوقفت على مفترق طرق بين عدم مراعاة البيئة ومجاراة الفكر الغربي و

Dental records recently used in forensic medicine to help in human identification, based mainly on radiograph images. The aim of our study is to automate this process, using image analysis and pattern recognition techniques. Postmortem radiographs, including dental radiographs, with a database of ante mortem radiographs searching, in order to get the closest match with respect to some distinct features. Contours of teeth are used as the feature for matching, since they remain more invariant over time compared to some other features of the body. The work ineludes two stages: radiograph segmentation, with pixel classification, and contour matching Probability model is used to describe the distribution of object pixels in the image. Results

The performance of thermal storage porous wall with vents (gravel material) is analyzed for
passive solar heating system under Baghdad climatic conditions by comparing it with conventional
wall (Concrete wall) for a variety of control strategies. The variation has been calculated during a
period of heating season for three months from December (1999) to February (2000) by using
computer simulation with MATLAB language (Ver.6.5). A mathematical model containing the
governing differential equations of heat transfer through the wall and glazing under unsteady heat flow
was performed by using “control volume” technique to obtain the temperature distribution within the
wall. The study was carried out for a south facin

This work includes a numerical investigation of steady two dimensional laminar natural
convection heat transfer in glazed rectangular enclosure at different tilt angles ranged from (0o
to 90o) for Rayleigh number (103-106), aspect ratios(4,5, and 8),and Prandtl number (0.7). The
study considers the effect of different boundary conditions on the heat transfer within the
enclosure. The continuity equation, Navier-Stokes equations and the energy equation are
solved by developing a numerical model based on finite volume method using SIMPLE
algorithm with hybrid scheme to compute the velocity vectors, temperature, pressure, and
Nusselt No. (local and average). Results show an increase in heat transfer rate with increasing

In this paper existing group technology techniques are reviewed and an alternative method using probabilistic approach to machine-components grouping in cellular manufacturing systems is introduced where it is based on production flow analysis, which uses routing information. A common feature of this approach is that it sequentially rearranges row and columns of the machine part incidence matrix according to predefined index and block diagonal is generated. The steps of this method are to assign the 1's in each row and column a probability weight, which alternately rearranged in descending order until a block diagonal matrix is created. It does not need to decide in advance, the number of required cells. It also overcomes the limitation

Friction stir spot welding (FSSW) is a promising solid state joining process and is widely being
considered for automotive industry. In this work mechanical properties of friction stir spot welded joints were investigated for ISO(426/1CuZn10) copper alloy. The effect of main welding parameters were studied including, welding tool rotational speed, preheat time (15, 30)s , plunging time (10,30)s , dwell time 10 s ,plunging depth (0.7,0.8) mm. Group of matrices of welding parameters were used to study the effect of each parameter on properties of welded joints. Series of (FSSW) experiments were conducted using manual drilling machine. Effect of welding parameters on mechanical properties of welded joints were investigated using tensile

In this paper, three types of epoxy-based coatings (Polyamide, pure Polyamine, and Polyamine reinforced by glass-flake) used as a lining for potable water tanks were studied using experimental and finite element methods. Tensile, impact, and fatigue tests were conducted on uncoated and coated AISI 316 stainless steel. The test results show that the applied epoxy based coating improves the mechanical properties, increases of fatigue crack resistance, and enhance the dynamic fracture toughness. The fatigue crack propagation is influenced by the compositions of epoxy coating, and the glass-flake improves the coating resistance to fatigue crack propagation compared to other types.

Iraqi paraffin wax (1.0 wt% aromatic content and 4.4 wt% oil content, Basrah origin) was hydro treated over commercial Pt-Re/y-Al203 catalyst in order to study aromatic removal reaction (de-aromatization) kinetics. Reaction temperature varied from 453 to 533 K over a liquid hourly space velocity from 0.5 to 4.2 h. Hydrogen pressure was kept constant throughout all the experiment at 3.6 Mpa with hydrogen to wax ratio about 400 m/m Kinetics analysis showed that the hydro-de-aromatization reaction followed a second order kinetics model. Energy, enthalpy and entropy of activation of hydro-de-aromatization reaction were 17.2 RJ/mole, 13.1 kJ/mole and -16.9 J/mole K, respectively.

In this paper the hardware implementations is investing of 8x8 Discrete Cosine Transform (DCT) and Inverse Discrete Cosine Transform (IDCT) on different Field Programmable Gate Array (FPGA) technologies using the modified Loeffler algorithm. The investigations involved simulations and synthesis of Very High Speed Integrated Circuit Hardware Description Language (VHDL) code utilizing recent FPGA families of Xilinx, Altera, and Lucent. The paper achieving the most demanding real-time requirements of some standardized frame resolutions and rates. Synthesis results for 8-point DCT/IDCT implementations indicate operating frequencies of 50 MIIz, 60 MHz and 22 MHz for the investigated Xilinx, Altera and Lucent FPGA chips, respectively. These fr

The flexural vibration characteristics of rectangular plates with linearly varying thickness is examined. The fourth order differential equation is solved by using Lagrange multiplier method. The thickness of the plate varies linearly along x axis and this variation is taken to be symmetric with respect to the middle surface. Simplicity and quick convergence is the advantage of the method in comparison with other much more laborious numerical metods which require extensive computer facilities A power series is used as an admissible function for the displacement function

This work covers the investigation of the effects of space environments factors on spacecraft structure. The satellite operates on a low earth orbit at circular (500,500) km, and subjected to different torques in space environments.The purpose of this paper is to develop the satellite structure design and test it to obtain the mechanical behaviour of structure. The satellite used so far is spin - stabilized, and rotating about one axis in 3 rpm. A configuration to the structure is suggested to be hexagonal; the dimension of structure is 110cm in diameter and 85cm high. The general static and dynamics tested of the system are verified, and analyzed to find the stress,strain, and vibration on the structure.

An experimental investigation was conducted to study the various parameters affecting the production of oxalic acid by the action of concentrated nitric acid on carbohydrates. Two feedstocks were studied, viz., dates fruit and dates syrup. The study also covered the effect of the amount of nitric acid and catalyst used in addition to employing two acid concentrations (67 wt.% and 98 wt.% acid). The results showed that when using 67 wt.% nitric acid, dates syrup was best suited as a raw material. And the best amount of nitric acid and V₂O, catalyst were in the ratio of 150 mls: 25 mg per 50 g feedstock. When using 98 wt.% nitric acid, no catalyst was required for the reaction and the reaction proceeded violently with the evolu

in the modern field of heavy ion atomic physics, determined through Lorentz transformation [W. Greiner 1997]. At high energies one must investigate the relative wave equations. This means equations, which are invariant under Lorenz transformation. The Lorentz transformation is so important, that it needs, to be derived on a more logical basis. Many textbooks and research papers have derived Lorentz transformation by different postulates [Anderson, J.L. 1967][G. Nadean 1962][H.A. Atwater 1974], which are not treated electro-dynamically this paper exhibits a method of finding the Lorentz transformation by exploiting the Maxwell's famous equations of the electromagnetic field equations

The effect of fiber orientation angle of composite materials on the gear tooth root stresses is analytically investigated in order to select the required orientation of the fibers inside the gear tooth. which leads to improve the gear tooth strength. The effect of geometrical parameters (loaded or unloaded pressure angles, number of teeth, radius of fillet and profile correction) and type of fibers glass, graphite and boron) are also studied. A stress analysis using the finite element method is performed for reinforced gear subject to bending loads. The results indicate that there is an effect of the fiber orientation on the root stresses of the gear tooth, and also, there is a direct proportionality between the improving of the gear str

A study concerns the dispersion of pollutants in Diyala River using one-dimensional Finite ditference technique (implicit method) to solve the simplified dispersion equation. The model starts at Diyala barrage and extended to the confluence of the Tigris Diyala rivers, and for 203-Km length. The simplified dispersion model results were verified by comparison with the analytical solution for different time increments. The calibration of the model was conducted on 31/11/1998 using measured data (discharge, velocity, cross sectional area, total dissolved solids (TDS), chloride CL and sulfate (SO)) concentrations at the same day and the results indicated a good agreement between the computed and measured data. The verification of the model i

Now days: large and small manufacturing companies own several numerically controlled (NC) iathe machines. hey are finding that NC/CNC machines can make dramatic saving possible. Certain aspects of NC/CNC shop operations require a high skilled operator level than conventional method. So that the need to develop a computerized technology to support the adoption of these machines and get the maximum benefits that's offer is highly recommended. The present work aims to develop such system that stand over the most modern available technologies to support this task. The system database is used to organize the factory data. The database hold factory lathe machines delinition at current state tooling and the available tools and materials with th

 procedure is presented to calculate an equivalent diameter for soil grains to be used to calculate the specific surface of the soil. The typical grain size distribution curve is expressed as a normal probability distribution cumulative curve and the frequency corresponding to the equivalent diameter is accordingly found. This frequency is adopted as the percent finer corresponding to the equivalent diameter. A relation is given for the calculation of the specific surface using the equivalent diameter. Grain size distribution curves of many soil samples are collected. A value for the specific surface of each soil is determined summing the surface area of subintervals in the distribution curve. The values of specific surface obtained

Supersonic gas jets in confined liquid metal atomizing nozzle were studied by using the method of characteristics. Nitrogen at operation (stagnation) pressure of (1.65Mpa) was used in the study, with three different values of ambient pressure (1.25, 1.52 and 1.75 bar). For all the three values, the nozzle is over expanded. The Mach number at the nozzle exit for all the investigated cases was (2.64). The pressure and Mach number of the atomizing gas at various lattice points downstream of the nozzle exit were found. Besides, the effect of heat transfer from the liquid metal (aluminum) on the gas flow behavior was also investigated, The results showed that the stagnation temperature rise of nitrogen caused by heat transferred from aluminum

Many studies and researchers have reported significant evidence that some physical properties of water can be changed as it passes through a magnetic field that can improve water use.  This can have a promising potential for applications, especially in the fields of irrigation and drainage. In this research, magnetized water was used to leach salt-affected sandy loam soil. A test rig was designed and constructed to investigate the effects of magnetized water on leaching soil. The rig consists of a magnetization device that can provide variable intensity. Water was supplied from a constant head reservoir to the magnetization device then to the soils that were placed in plastic columns. Five different magnetic intensi

In this paper, ceramic water filters were produced by using ten mixtures of different ratios of red clay and sawdust under different production conditions. The physical properties of these filters were tested. The production conditions include five press pressures ranged from 10 to 50MPa and a firing schedule having three different final temperatures of 1000, 1070, and 1100˚C. The tests results of the physical properties were used to obtain best compatibility between the hydraulic and the mechanical properties of these filters. Results showed that as the press pressure and the firing temperature are increased, the bulk density and the compressive and bending strengths of the produced filters are increased, while, the porosity and absorp

Physical and chemical adsorption analyses were carried out by nitrogen gas using ASTM apparatus at 77 K
and hydrogen gas using volumetric apparatus at room temperature respectively. These analyses were used for
determination the effect of coke deposition and poisoning metal on surface area, pore size distribution and
metal surface area of fresh and spent hydrodesulphurization catalyst Co-Mo\Al2O3 .
Samples of catalyst (fresh and spent) used in this study are taken from AL-Dura refinery.
The results of physical adsorption shows that surface area of spent catalyst reduced to third compare with
fresh catalyst and these catalysts exhibit behavior of type four according to BET classification ,so, the pores
of these sample

There many methods for estimation of permeability. In this Paper, permeability has been estimated by two methods. The conventional and modified methods are used to calculate flow zone indicator (FZI). The hydraulic flow unit (HU) was identified by FZI technique. This technique is effective in predicting the permeability in un-cored intervals/wells. HU is related with FZI and rock quality index (RQI). All available cores from 7 wells (Su -4, Su -5, Su -7, Su -8, Su -9, Su -12, and Su -14) were used to be database for HU classification. The plot of probability cumulative of FZI is used. The plot of core-derived probability FZI for both modified and conventional method which indicates 4 Hu (A, B, C and D) for Nahr Umr forma