Journal of Engineering and Sustainable Development (JEASD)

The deflection of a member can be determined more accurately from the values of the mean curvatures of a number of sections using simple geometrical deflection-curvature relations taking into account the effect of tension stiffening. Thus, the "The Proposed Mean Curvature" idealization is derived in this work exclusively for prestressed concrete members taking into consideration the effect of cracking of these members. It shows better agreement with experimental data than the conventional models, which are established essentially for normal strength concrete and do not fit higher-strength concrete. The computer program "PPCD" is developed in this work following the proposed model. Immediate and time dependent deflections of prestressed concrete beams can be computed. Concrete compressive strength, tension-stiffening effect, and time-dependent factors are included in this program. This program has been verified once to typical studied example with varying concrete compressive strengths and furthermore to an experimental data.
The results indicate that the accuracy of The Proposed Model in deflection predicting is acceptable for partially prestressed concrete members of any concrete compressive strength.

This paper describes an optimum design of continuous microstrip tapers using genetic algorithms (GA’s).
This approach has a few advantages: giving a clearer and simpler representation of the problem. In this method genetic algorithms deal with the reduction of the reflection coefficient pattern for a certain range of frequencies. Three different continuous transmission line tapers are compared here, linear, exponential, and Chebyshev with the genetic algorithms.
Genetic algorithms can obtain very small reflection coefficient within the range of frequency, but on the other hand the characteristics impedance form obtained is difficult in practical.

There has been an increase in the use of articulated tracked vehicles during the past two decades. This is because of the limitations imposed on steering single tracked vehicles. In this work, which is regarded as the first part of dynamic analysis of steering articulated tracked vehicles, the effect of centrifugal acceleration has been taken into account, at low and also at high speed. The object is to compare steering analysis between single tracked vehicles and the wagon type of articulated tracked vehicles in the influence of centrifugal force.

This paper deals with secret-key steganography approach of data hiding, it takes advantage of images with dark background or boundaries. The main goal is to hide a text in an image without drawing suspicion about the hidden information. The developed algorithm compares between the ASCII code of the text character and the value of the image pixel, if they are equal, the pixel position (else Character ASCII code) will be stored in the image border after encrypting it. This developed algorithm has been applied on (grayscale, 256-color, and true color) images, good results were obtained with true color and gray scale images . The 256-color images may draw suspicion about the hidden information. Binary and multispectral images cannot be used in this algorithm.

oday's project construction management faces many challenges due to the increased complexity and variety of projects. The need for continuous control of time, cost and performance of project to satisfy clients needs, gives rise to search for new concepts in projects construction management. Construction management makes time cost trade-off decisions every day in planning and managing their work. This paper describes the typical pragmatic approach that managers take in making time-cost trade-off. It then describes computerized crashing technique to be used easily by the construction management.
The objective of describing time-cost trade-off the critical path method analysis is to establish a minimum time requirement for projects, making use of durations of each activity at minimum cost.

A cavity model well suited for computer aided design is presented and developed to
study the rectangular microstrip antenna. The patch is described by geometrical and
electrical parameters. The resonant frequency, resonant resistance, bandwidth, efficiency
and other electrical parameters of RMSA have been presented as a function of varying
the patch dimension and substrate parameters. The accuracy and usefulness of the
method are investigated through comparison with experimental results as well as other
previous theoretical methods.

The aim of the present work is to develop the computer program to simulate the steady
two-dimensional laminar and turbulent flows. The finite volume method is used to solve the
flow governing equations numerically. The Navier-Stokes equations are solved for the
velocity flow field. Since all the variables are stored at the center of each control volume.
The correct velocity field is then used to solve k-epsilon equations. The eddy viscosity, that
represents the influence of turbulence on the mean flow field, can be calculated from those
values of k and epsilon obtained. The boundary layer on a flat plate is employed as a test
case because it is one of the standard famous problems for the validation of CFD program
and a Reynolds number is chosen at 1400 as a case study. It is found that the computed
results are in good agreement with the available published data. Moreover, the governing
equations are solved by using body-fitted coordinates system so that this computer program
can be developed further for the simulation of laminar and turbulent flows over any object
of complex geometry in the future.

In this paper, parallel Concatenated Convolutional Codes (PCCCs) is modeled as a special case of Serial Concatenated Convolutional Code (SCCCs). Consequently, resulting in Adaptive (parallel/serial) concatenated convolutional code in which the same encoder
and decoder can be used for both types of concatenated convolutional codes. To achieve this goal some interleaver restrictions are made to modify the classical structure of Semi-Random interleaver. The decoding stage is based on classical SCCC iterative decoder,
with added interleaver restrictions. The core of decoder structure is a soft-input soft-output (SISO) a posteriori probability (APP) module. Log-Map is used as (APP) for its superior performance. This work also presents some classical structured interleavers such as Block and Circular interleavers, adding to them the presented restrictions for sake of comparison. The resulted performance curves from computer simulation shows that degradation signal per bit energy to noise ratio (Eb/No) for the proposed decoder as compared to the classical PCCC is no more than 0.45 dB at less than 10-5 bit error rates (BER),over Fading channel in worst case.

The Karkh water project has been constructed and put in operation in 1986, in order to supply drinking water to the Karkh district on the right side of Baghdad. Due to deficit in water in the Rusafa side the Baghdad Water Supply Administration (BWSA) has suggested a reasonable solution in which about (455000 m3/day) of water was to be transferred from Karkh to Rusafa water services. The transfer process, controlled by throttling two valves on the North reservoir in the Karkh service system. The throttling process, however, worked randomly creating many hydraulically problems. Therefore, it becomes very essential to suggest a proper solution so that a fair distribution could be achieved. Two solutions have been employed the first is by operating partial throttling of the terminal discharge valve at north reservoir (TDV). The second solution, which is the safest, is to use boosting pumps to transfer 455 MLD to Al-Rusafa side so as to reserve the right amount of water to all reservoirs. In finding the best locations of boosting pumps the technique of contour line has been used, the optimal locations and the characteristic curves of the pumps have been discussed....

This investigation includes an experimental study of the changes in compressive strength, splitting tensile strength, modulus of rupture and static modulus of elasticity after exposure to high temperature ranging between 250 to 750°C of plain and steel fiber reinforced concrete (SFRC) in comparison with ordinary temperature (25°C). Hooked and straight steel fibers with aspect ratio of 60 and two different percentages by volume (0.5% and 1%) were used. Each group of specimens was heated to a specified temperature and kept at that temperature for one hour before being gradually cooled to room temperature, and then they were tested. The results show an appreciable decrease in compressive strength, splitting tensile strength, modulus of rupture and elastic modulus after exposure to temperature higher than 350°C of both plain and SFRC. The inclusion of fibers very slightly affects the compressive strength of concrete at temperature below 350°C, while the loss in compressive strength for SFRC is lower relative to plain concrete after exposure to temperature higher than 350°C. The results also show that the loss in splitting tensile strength and modulus of rupture for SFRC is appreciably lower in comparison with that of plain concrete for all heating temperatures up to 750°C. The volume content of fiber slightly affects the compressive strength of concrete; also the type and volume .....

This paper investigates the use of a Field Programmable Gate Array (FPGA Xilinx Virtex-II) to perform hardware implementation for low speed part of JPEG2000 to achieve a real time JPEG2000 system. In this paper multi processes modules written in the VHDL is proposed that can be used to accelerate an existing software implementation of JPEG2000.

There is a simple linear relationship between the static and dynamic elastic module, this lead to hope that using dynamic elastic modulus may remove the problems in measuring the static elastic modulus of concrete. Normal strength concrete (mix (1)) exhibited lower dynamic modulus of elasticity than that of high strength concrete (mix (2)). The reason for that was the difference in the quality of past, due to the difference in the water content of these mixes. Type (HB) the quartz is higher in static modulus of elasticity of concrete for cylinder specimens than types HA (dolomite), HD (dolomite content organic), HF (round gravel), HE (rough gravel) and HC (calcite) by (9%), (19%), (20%), (21%) and (25%) respectively in 91 days. Type (HB) the quartz is higher in dynamic modulus of elasticity of concrete for cylinder specimens than types HA (dolomite), HC (calcite), HD (dolomite content organic), HF (round gravel), and HE (rough gravel) by (4%), (22%), (23%), (23%) and (25%) respectively in 91 days. The ratio of static modulus of elasticity of concrete to the dynamic modulus of elasticity of concrete (Ec/Ed) for the normal strength concrete (mix (1)) is between (36 to 55%). While for high strength concrete (mix (2)) the ratio is between (15 to 27%).

The aim of this paper is to investigate the effect of impulsive noise on the performance of the speech denoising using Discrete Wavelet Transform (DWT). The employed model of impulsive noise consists of Bernoulli distributed impulse arrivals and Gaussian distributed amplitudes of the impulses. In this study DWT algorithm has been applied for the suppression of ambient noise. This method is based on thresholding the wavelet coefficients, that can be done by standard deviation method for each frame by level dependent thresholding using different types of threshold (semisoft, hard soft and super soft) in channel contains impulsive and Gaussian noise together. The results of simulation indicate that using discrete wavelet transform in speech denoising application provides a good quality and semisoft threshold gives the best performance.

In this work, five destructive and nondestructive tests using three different types of specimens were carried out to study the mechanical properties of steel fiber reinforced concrete before and after exposure to elevated temperatures. Forty-five (100 mm) concrete cubes were used to investigate both concrete compressive strength and ultrasonic pulse velocity (UPV), while the flexural strength and dynamic modulus of elasticity (ED) were studied using forty-five (100x100x500 mm) prisms. Also, the splitting tensile strength was studied using (100 mm) diameter and (200 mm) height cylinders. These specimens were heated to four temperature levels of (150, 350, 500 and 700 oC). A single concrete mix with three steel fiber contents (Vf %) of (0.0, 0.5 and 1.0 %) by weight was adopted. The test results of this study show that the use of steel fibers enhance the brittle mode of elevated temperatures affects all concrete properties, however, the amount of strength decrease depends mainly on the type of stresses in each test and on the level of temperature. Another observation is that the presence of steel fibers enhances splitting tensile strength, flexural strength, and ED significantly, while this effect seems to be less significant or even insignificant for compressive strength and UPV.

In this research, the vortices are used in the heat exchange between fluids, relying on previous studies which indicated that the vortex flow causes a sharp increase in the heat transfer rate. This means that the area needed for heat exchange surface is in this case smaller than that of the non-vortex flow. Hence, a heat exchanger is constructed from three smooth concentric cylinders of different size, the inner of which is rotatable, whereas the others are fixed. On the other hand, the inner and the outer cylinders are adiabatic whereas the middle cylinder which corresponds to the fluids heat exchange surface is made of very high thermal conductivity metal as the Aluminum.Water and air are used here as the heat exchange fluids .A Taylor vortex flow is induced in the hot water at (80˚C) occupying the annulus between the inner and the middle cylinders by rotating the inner cylinder to or above a certain speed limit of 65 RPM which corresponds to the critical Taylor number of 1.162E4, as the inner cylinder speed was varied from 0 to 80 RPM. Mean while, a swirl is generated in the cold air (at room temperature) within the annulus between the middle and the outer ......