Journal of Engineering and Sustainable Development (JEASD)

This study reports the influence of different percentage additives of fly ash on the swell characteristics and engineering properties of laboratory-prepared heavy clays. For this purpose the effect of 0-25% of fly ash on the swelling properties of expansive soils have been studied on samples with various curing time (0, 10-days and 30-days). Moreover, the effects of such addition on other mechanical properties of expansive soil (such as grain size distribution and consistency limits) are taken into consideration.
Fly ash proved its efficiency in improving the swelling characteristics. The results show an increase in swelling reduction with increasing fly ash percent increase and curing time

The Retinex is an image enhancement algorithm that improves the brightness, contrast and sharpness of an image. The core of Retinex computation is clearly specified in recent Matlab implementations. The recent Retinex algorithms use several free parameters to control the enhancement degree. In this paper we introduce a proposed algorithm for image enhancement using Retinex algorithm. The proposed algorithm based on the previous algorithms for Retinex computation, the major difference here is that the main control parameter for enhancement degree (enhancement factor) is computed automatically during processing according to a proposed relation introduced in this paper.
The proposed relation depends on the illumination degree of the areas (blocks) of the scene under processing this is useful for very bad illumination scenes or images. This research also shows that the proposed algorithm is useful for the images with medium illumination.

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The aim of this work is to determine the stress patterns of a prosthetic socket. This allows the socket geometry to be more accurately modeled. The analyzed socket is a medium length lower left leg.
The pressure values between the stump and the socket are taken from published data. While the loading on the socket base is evaluated theoretically. Three types of sockets, PP (5mm), PP (3mm) and a standard laminate (3mm) have used in this work.
The results showed that the stresses produced in the socket frame are low comparing with the yielded stresses of the materials. The PP (5mm) and the laminated socket show deformations below the critical value (i.e. 2mm), while the PP (3mm) gave a deformation of (2.9mm) which is higher than the critical value

This paper presents investigation on the strength and deformation characteristics of reinforced normal and high strength concrete rectangular beams failed in shear and repaired by epoxy injection.Eight simply supported reinforced concrete beams without shear reinforcement are tested, four of which are made with normal-strength concrete (NSC) and four with high-strength concrete (HSC). The span of the simply supported beams is 1.28 m with 100 mm wide by 200 mm deep cross section. All are tested under two-point loads.Method of epoxy injection is used to repair cracks in the failed-in-shear beams. Careful repair process is adopted and proved successful.Main conclusions are: successful repair method is used to increase or at least restore shear capacity of beams; the increase is observed higher in normal-strength beams; repaired diagonal shear cracks do not reopen (generally) after retesting, instead, new nearby diagonal shear cracks are developed and the repaired beams show a lower stiffness and greater ductility than original beams.

urbo codes are suitable for deep-space communications, because of the codes astonishing performance at low values of signal to noise ratio (SNR) and their ability to achieve near Shannon limit of channel capacity.
In this paper the performance of turbo codes in AWGN channel is evaluated under different conditions and circumstances. The deep-space channel is almost exactly modeled as a memoryless additive white Gaussian noise (AWGN) channel that formed the basis for Shannon’s noisy channel coding theorem.
A comparison between the modified BCJR* decoder, which uses modified forward-backward metrics and the Soft Output Viterbi Algorithm (SOVA) decoder, is also presented.
Simulation results for the turbo encoder-decoder system show that care must be taken in choosing different parameters that govern the turbo encoder- decoder scheme, also the enhancement is required for low rate (rate 1/4) turbo encoder that uses symmetrical component encoder.

This paper presents a design procedure for a constant stress low pressure steam turbine blade. Such blades suffer from different types of loadings leading to different types of stresses, like tensile and bending stresses due to centrifugal force and steam flow loading. The centrifugal force is one of the problems that face the designers of blades especially the long ones. One way to tackle this is by using twisted blades and/or using variable cross-section area blades. Six types of blades were studied in this paper. One for constant cross sectional area blade as a reference. The other five are for reducing cross sectional area blades of varying curvature. Reducing the cross sectional area reduces the mass of blade and hence reduces the centrifugal stresses. The performance of the cases was then checked and found to be within satisfactory ranges. The results obtained are then utilized in the design of the constant stress blade. Which was checked with references for three locations (stages) and was found satisfactory?

The objectives of this investigation are to study the efficiency of different shapes of steel plate embedded in flat plate slabs as shearhead reinforcement. The effects of the shear reinforcement (steel plate) on the cracking load, ultimate load and ductility are examined.
Fourteen test slabs were prepared in this study. The models simulate the region of negative bending moment around an internal column supporting a flat plate roof. Two specimens were cast without punching shear reinforcement and twelve specimens were cast with different shapes of steel plate as punching shear reinforcement. The test loads were applied incrementally till the ultimate carrying capacity was reached. Deformations, crack patterns and ultimate loads were recorded

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Error correction codes have been successfully implemented in wire-line and wireless communication to offer error-free transmission with high spectral efficiency. The drive for increased transmission capacity in fiber-optic links has drawn the attention of coding experts to implement forward error correction (FEC) for optical communication systems in the recent past. Particularly, the ITU-T G.975 recommended Reed-Solomon RS (255, 239) code, is now commonly used in most long-haul optical communication systems. It was shown that the code offers a net coding gain of around 4.3 dB for an output bit-error rate of 10-8 after correction. The Monte-Carlo simulation and theoretical performance analysis for the RS (255,239) code with 6.7% redundancy were presented for a completely random distribution of errors over an additive white Gaussian noise (AWGN) channel with BPSK signaling and hard decision decoding. In addition, net coding gain comparison was done between the ITU-T G.975 standard and that offered by the RS (255, 247) and RS (255, 223) codes with 3.2% and 14.3% redundancy respectively.

The present research studies the effect of changing dry density on expansive soil and the effect of applied load on expansive behavior of soils together with the comparison of the values of swelling pressure with free swelling. The two types of effect have been studied on three samples of a mixture of bentonite and sand. After the identification of the physical characteristics of the sand and bentonite, the sand was used as a basic and natural material to decrease soil swelling. The gained results proved that loads play an important role in reducing the ratio of swelling and it is necessity to obtain the required field density that lead to reducing swelling.

This investigation is concerned with the prediction art of the nucleate boiling heat transfer coefficient obtained from boiling on enhanced surfaces. It is devoted to study the enhancement factor of single enhanced tubes boiling pure liquids at atmospheric pressure which in turn reflects the boiling performance of the heating element during the process. Two surfaces of the integral machined structure; Gewa-T and Low Finned, tubes were considered. A new correlation for the estimation of the heat transfer coefficient in the nucleate region was developed for these tubes. This equation was formulated by a dimensional analysis based on the Buckingham (π) theorem to handle the various variables considered to describe the mutual effect of the surface and liquid on the enhancement factor of a given surface structure. It is obvious that the enhancement factor is a strong function of the fin shape of the enhanced surface structure and boiling liquids physical properties.

Orthogonal frequency division multiplexing (OFDM) or multicarrier transmission has been shown to be an effective technique to combat multipath fading in wireless communications. It has been successfully used for HF radio applications and has been chosen as the standard for digital audio broadcasting and digital terrestrial TV broadcasting in Europe and high-speed wireless local areas networks.
This paper describes the concept behind parallel data transmission and the configuration of an OFDM transmitter and receiver when used four type of rectangular Mary QAM modulation (QAM, 16QAM, 64QAM & 256QAM). Two type of error evaluated (bit error rate BER & packet error rate PER) for two typical channels, AWGN channel & (one or two path) Rayleigh fading channels.

The Non-linear analysis of members having concave configuration shapes is considered using stability functions. The accuracy of results has been verified by using the finite element method by discretizing the beam-column member into different numbers of an equivalent prismatic element.
The change of member lateral stiffness and change of member length are considered by using the stability and bowing functions after deriving them here.
The axial deformation of concave beam-column including the effect of bowing is compared with the same of that without bowing effect to estimate the exact deformation of the beam-column under the same boundary condition and applied load.

In this paper image coding for (Computer Generated Hologram) CGH technique, is investigated ideal analysis is undertaking to build and to constructed hologram by using wavelet theory and the images taking in to construction binary cell oriented holograms. This model is used to test performance for the image of CGH. The success of any transform coding technique depends on how well the biases functions represent the signal features. The discrete wavelet transform (DWT) performs analysis of a signal; this enables an efficient representation of smooth and detailed signal regions. Furthermore, computationally efficient algorithms exit for computing the DWT. For this reasons, recent image standards such as TIF us the wavelet transform. It is well known that orthogonally and symmetry is desirable transform properties in image CGH application. This paper discus analyzes the impact of these wavelet characteristics on image performance; the analysis allows us to the first reasons for the small performance gap between the scalar wavelet and another method.

No-fines hollow concrete blocks using the 10-mm maximum size of aggregate and improved by Styrene Butadiene Rubber (SBR) polymer is manufactured in one of Al-Anbar governorate blocks factory. The concrete mixes, by weight, were (1:5) and (1:6) (cement: aggregate). The polymer was added as percentages of cement weight in 3%, 6%, and 10%. The following tests are used in this study: Compressive strength, density, absorption, and compressive strength after exposure to high temperature. The tests results were compared with the corresponding results of normal blocks which made in the block factory with (1:2:4) (cement: sand: gravel) by weight mix. Results also proved that the addition of polymer leads to improvement of block properties like compressive strength and compressive strength after exposure to high temperatures. The maximum increase in compressive strength according to blocks made by reference mix was (12.69%) in (41) day-test age for blocks with mix proportion by weight equal to (1:5) (cement: agg.) with (6%) (polymer: cement) ratio and for the same blocks, the percentages of increasing equal to (132%) according to blocks factory. This addition also leads to an increase in the density of blocks and a decrease in water absorption. However, for high SBR content (10%), the traditional method of block production is not adequate for no-fines polymer concrete blocks.