Journal of Engineering and Sustainable Development (JEASD)

In this study, a theoretical analysis is presented for estimating the in-plane large displacement elastic stability behavior of steel frames having prismatic and non-prismatic members (Tapered and non-linearly tapered) with end gusseted plates subjected to increasing static loads. The analysis adopts the beam-column approach and models the structural members as beam-column elements. The formulation of the beam-column element is based on Eulerian approach allowing for the influence of the axial force on bending stiffness. Also, changes in member chord length due to axial deformation and flexural bowing are taken into account. The effect of gusseted plate is taken and the modified stability and bowing functions are derived for gusset plate with prismatic and non-prismatic members (Tapered and Non-linearly tapered).The post-buckling analysis is studied, and the incremental load control with different load increment strategies and the modified Newton-Raphson method with different iterative strategies are used to obtain the complete load-displacement curve.

In this research parallel concatenated convolutional coding with iterative decoding is examined for data transmission over the downlink of a WCDMA system employing BPSK modulation and coherent Rake receiver. Performance of parallel concatenated convolutional coding is studied in a frequency selective Rayleigh fading channel, new type of external interleaver which is called Dithered Golden Section Interleaver (DGSI) is used. The effect of correlated fading on the performance of the proposed system is investigated by considering external block interleaver delays of 10 ms at mobile speeds 5 km/h. Simulation results show that the employing of this type of interleaver is outperforming at high signal to noise ratios the classical random interleaver.

A significant amount of engineering judgment is required in the decision of whether to accept the deviation in the quality of asphalt concrete from job mix formula or specification requirements and the remedy to be taken regarding the measures and penalty to be decided. Such measurements and decisions are difficult to confine. In this paper, attention is directed toward the quality of asphalt concrete mix constituents (aggregate gradation, asphalt content & voids) and their physical properties (Marshall Stability & flow).
The acceptable quality of the constituents depends on general requirements of the material. The development of an advisory expert system in the domain of flexible pavement quality is presented. The developed system is called ACQAES (Asphalt Concrete Quality Advisory Expert System).

In this paper, the performance of frequency hopping spread spectrum systems employing noncoherent reception and transmission diversity is analyzed for frequency selective Rayleigh fading (FSRF) channel.
Two different types of frequency diversity systems, fast frequency hopping (FFH) system and a multicarrier frequency hopping (MCFH) system are investigated. In order to combine received signal from transmit diversity channel, the optimum diversity-combining rule based on the maximum-likelihood criterion is described.
MCFH systems are found to outperform FFH systems when the channel delay spread ratio is severe at the same diversity order at low error rate. The optimum normalized frequency deviation for MCFH systems is found to increase with delay-spread ratio.

This study presents the benefit gained from using steel fiber reinforcement on concrete mixture. The effect of fire on compressive strength is investigated. Two different tests, one of them is the non destructive test which is the ultrasonic pulse velocity (UPV) test and the other is the destructive compression test, are carried out using (10cm) cubs.
Forty-eight cubes (half of them are with steel fiber reinforcement of fiber/concrete ratio of (0.01) by volume and the remaining cubes are without fiber reinforcement) are heated to temperature levels of (100,200,300,400,500,600 and 700°C). Then after specimens are air cooled and (UPV) test is done, the specimens are destructively tested.
The results indicated that the addition of steel fiber increases the compressive strength at all tested heating levels with a maximum percentage increase of (56.9%) at temperature level (500°C) in spite of that they have the same behavior but the residual compressive strength decreases with the addition of steel fiber for the tested heating levels lower than (400°C) and increases for the heating levels above this degree.

This work presents the development of a secure communication system that support protocols with built-in security capabilities, which are authentication and integrity capabilities. These capabilities can be achieved by applying a new proposed authentication protocol within the standard protocols.
The proposed authentication protocol is based on two different authentication
services, which are Two-Way Challenge-Response authentication service, and One-Time
Password authentication service. These two services are based on two of the most secure
hashing functions, which are Message Digest version 5 (MD5), and Secure Hashing
Algorithm (SHA-1).
The proposed communication system will be more secure than systems that depend only on cryptography algorithms, since the attacker should analyze and break two different security service algorithms

All tunnels require ventilation to maintain acceptable levels of contaminants produced by vehicle engines during normal traffic operation (normal ventilation), and to remove and control smoke and hot gases during a fire emergency (emergency ventilation) ref. (7).
To protect passengers, personal and equipment in a tunnel fire, it is important to understand and predict the temperature distribution through the tunnel during the tunnel fire. In this paper, a computer program (Tunnel) has been built to investigate the temperature profile along the tunnel for passenger car and three passenger cars with and without ventilation by using (explicit F.D) method .
In this paper, also we will study the effect of the system ventilation on the temperature profile and estimate the required time to return temperature to ambient value for passenger car and three passenger cars

In this paper, (15, 11) and (255, 239) Reed-Solomon codes have been designed and Implemented using ALTERA Field Programmable Gate Array (FPGA) device. The design is carried out by writing VHDL modules for different encoder and decoder components. The waveforms are tested using the package MODEL-SIM 5.4a. While synthesis reports and board programming file are obtained using the package QUARTUS II. ALTERA-FLEX10K10 FPGA board is used as a target device for the designed Reed-Solomon encoder/decoder. Simulation waveforms show that (15, 11) and (255,239) Reed-Solomon decoders could correct up to 2 and 8 erroneous symbols respectively

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

Digital PID controllers are widely used in industrial applications. They are used in autopilots, ship steering, and speed control of machines…etc. A digital computer with an interfacing device is used to implement such types of controllers.In this paper, the design of digital controller using FPGA is described. The design provides a minimization in the hardware design and reduction in the cost as compared with the digital control implemented using digital computers.The structure of the controller can be selected using 2 bit input binary value. The type of the structures is P, PI, PD or PID. The parameters of the controller are tuned from the outside of the FPGA controller. In order to test the design, a discrete linear 1st order model is implemented inside the FPGA. Also, the closed loop system was simulated using MATLAB/SIMULINK program. A comparison between the simulated and designed systems shows that the results are very acceptable and close to each other.

A study is made of the influence of thermal anisotropy on the transient temperatures distribution after a short time. Such problem simulate the general behavior of the composite long metal bar of rectangular cross-section where it is initially at a temperature To and it is then suddenly quenched in a large volume of fluid at temperature Tf , thermal conductivity is assumed orthotropic, having different x, and y direction properties. The heat dissipation during solidification process related to the transient temperature distribution, thus the directional metal conductivity ply an important role in the volumetric strains due to orthotropic thermal expansion and chemical shrinkage, as well as the dramatic changes of saluted metal. The presented study results show the anisotropic conductivity need for realable simulation procedure.

Ultimate capacity of composite concrete-steel deck (a composite slab) is the topic of this study. A composite slab consists of two or more structural components of different materials. The main aim of using a composite slab is to make full use of the beneficial properties of different materials. The upper and lower components in a composite slab are usually connected together by shear connectors. The present study is concerned with the ultimate capacity of composite concrete-steel deck-one way slabs (composite slabs), the ultimate capacity of composite slabs with longitudinal bars and ultimate capacity of composite slabs with shear reinforcement. The study also includes the effect of using different spans of steel decks.The tested slabs are loaded to failure by means of two-point load tests. It is found that a composite slab with longitudinal bars (RLB) gives high Ultimate load capacity. The mean ratios of ultimate load capacity for the composite slabs with longitudinal bars (RLB) to reference slabs (RS) are (1.78) and (1.98) of slabs which have length equal to (1600mm) and (1300mm), respectively.

Previous research indicated that; the addition of water-proof additives to a concrete mix will increase the hardened concrete water tightness, but it will reduce its strength. Normally, reinforced concrete footings are subjected to wetting and drying cycles due to the rise and fall of underground water levels. These cycles considerably reduce concrete durability, and also reduce the effective service life of reinforcement, due to its corrosion. In this research, experiments have been done to monitor the effect of adding different percentages of water-proof additive (2, 4, and 6) % by the weight of cement used in the concrete mix. Results have shown the reduction percentages of permeability, compression, splitting, and flexural strengths in the hardened concrete. Finally, the optimum percentage of the water-proof additive is reached, and a reduced percentage of concrete strength is suggested to be used during reinforced concrete footing design.