Journal of Engineering and Sustainable Development (JEASD)

Monopulse technique is the most common used technique in the tracking systems because it has the ability to obtain complete angle-error information on a single pulse. For one target, the antenna boresight of the monopulse tracking system will track the target while for two targets (or more), the antenna boresight will tracks the direction of the center of energy that transmitted or reflected by these targets. This paper introduces the analysis of this phenomena and how to utilize it to deceive angularly the monopulse tracking system. This analysis consists of the direction determination of the center of energy transmitted (or reflected) by the two targets before reaching the resolution angle, then the correction in the direction toward one of these targets after the resolution angle. The optimum separation between the two targets for deception has been calculated. The results of this analysis and calculation show that, there is an acceptable miss distance from the target when the distance between the two targets was selected to be an
optimum distance.

In this work experimental and theoretical model predictions for thermal and hydraulic design of shell and tube heat exchanger are presented. The tests were carried out at hot fluid temperature range between (40) to (60) C° at atmospheric pressure for volumetric flow rates ranged between (800) to (1800) l/hr.
The model presented for this object was suggested to be accomplished by using the step by step technique. In this model, the heat exchanger was divided into longitudinal increments along the heat exchanger for both tube and shell sides. The output of each increment for both sides of process and service fluids including the thermal and hydraulic parameters are considered to be the input of the next increment and so on until the final temperature and load of the heat exchanger together with the hydraulic requirements were reached.
Two methods were applied in the suggested design model, Kern and Bell-Delaware, in
addition to the step by step technique. The prediction of heat exchanger performance of the
present model well agreed with the above mentioned methods.

This study presents experimental and theoretical investigation of shear behavior of hybrid reinforced concrete I-beams cast monolithically, but, the web is made with concrete differing from concretes of compression and tension flanges.A rational way has been used by replacing (or strengthening) a certain part(s) or layer(s) of I-shaped reinforced concrete beams by steel fiber reinforced concrete (SFRC) or high strength concrete (HSC). Three beams were tested in this investigation and only the concrete type of the web was varied. Experimental results showed that the ultimate shear strengths are increased (15 or 25%), while the reserve shear strength (after diagonal cracking) is increased (6 or 10%) for the tested beams containing SFRC or HSC in the web respectively. Crack arrest mechanism of steel fibers, and high compressive strength of concrete improved the tensile response, limited crack propagation, improved reserve strength and altered the failure mode. So, more safety was obtained.ANSYS finite Element models are used to simulate all tested beams.

Investigation of eddy-current problems through a thick sheet is presented based on the development of a complementary formulation for electric and magnetic field intensities. These two types of formulation (systems) can be solved independently and the two solutions complement each other. A comparison is made using a single variational principle, which involves both complementary systems simultaneously. Accurate results are given for estimating the resistance and inductance through which the eddy current can be estimated.

This paper presents a framework in which images can be transmitted over channels
with high packet loss rates with the addition of unequal amounts of forward error
correction (FEC). It develops an algorithm that can optimize the allocation of FEC to the
image data so as to maximize the expected image quality.
By using both the importance of the output of the image coder and an estimate of the
probability of losing packets, it considers distortion-rate tradeoffs in its assignments to
provide graceful degradation when packets are lost.
The algorithm is also modular in that it can use any compression scheme that produces a progressive bit-stream.

In this study, the last part of the preheater system in a cement manufacturing plant which is called pyroclon system is studied. The study covers the amount of tertiary air from cooler and its temperature effect on temperature of calcination also its effect on the amount of fuel that is supplied to pyroclon. Also, the study of the amount of hot gases from rotary kiln and its temperature effect on the temperature of calcination, and on the amount of supplied fuel. The results of the present work explained also the effect of quantity of the raw meal that enter the pyroclon and its temperature effect on the temperature of calcination and the amount of supplied fuel .Heat balance for pyroclon system and mass balance for all preheater systems and its chemical reactions are included. Then a computer program is constructed in order to calculate temperature distribution for gases and particles along pyroclon by considering the amount of the heat lost, which is transferred from the gas to particle and from the particle to the wall, also from the gas to the wall, depending on conduction, convection and radiation in order to find the exit temperatures of gas and particles from pyroclon and to find the range of the pyroclon working for different values of gas velocities and the amount of fuel supplied.

In conventional electronic ballast for a fluorescent lamp, inductor-capacitortransformer tank circuit is used. A Piezoelectric Transformer (PT) can potentially be used to replace such a tank circuit to save space and cost. In the past, ballast design using a PT requires selecting a PT from available samples which are normally not matched to the specific application and therefore resulting in poor performance, also piezoelectric transformer design has been difficult due to the complex interaction between the physical and electrical circuit characteristics. In this research, a design procedure has been developed for designing a PT tailored for 220-V 40-W electronic ballast with high efficiency (90%) and Zero-Voltage-Switching (ZVS) for the semiconductors without the use of any external inductance. In this design a round radial-mode piezoelectric transformer (Transoner) was used and to achieve an optimum solution, a 3-D graphic to circuit requirement is used which allows the engineer to design according to the circuit criteria, the design is programmed by using the MATLAB package.

Study the stability of slopes is of great importance for the geotechnical engineers. Stability analysis is required for engineering projects, such as natural stabilized slopes, embankments and cuts in road and excavation in soil. There are many methods used to analyze the slope stability problem. Limit equilibrium is most conventional method, which is used to analyze slope stability, which depends essentially on assuming a failure surface. In this research, the finite element method is used to analyze slope stability problems. A finite element program is used to analyze the soil slope stability according to the theory of elasto-plastic failure of visco-plastic method. Mohr-Coulomb theory is used to represent the surface failure. The study concentrates on computing the factor of safety for stability at different values of cohesion (C) and angle of internal friction (φ) of the soil. Comparison between the computer results with the traditional slip circle solution gave good agreements.

The flexural analysis of the composite specimens made from polymer matrix composite that was reinforced with different volume fractions of glass fiber and alumina powder (Al2O3) were studied here experimentally and numerically by using the finite element method. The composite specimens employed in this research made three ratios of volume fraction of glass fiber and five ratios of volume fraction of alumina powder (Al2O3). The results illustrated that the deflection increases in a linear relationship with an increase of the load, while decreases in a nonlinear relationship with an increase in the volume fraction of (glass) and (Al2O3) for both experimental and numerical studies. The maximum value of deflection for the specimen equals 1.85 mm at Vf of (glass) = 10% only and without Vf of (Al2O3). While the minimum value of deflection equals 0.392 mm at Vf of (glass) = 30% and Vf of (Al2O3) = 5% for the same value of load = 10 N and for experimental results.

Fourier analysis and wavelet analysis have often been used in time series analysis. Fourier analysis can be used to detect periodic components that have sinusoidal shape. However, it might be misleading when the periodic components are not sinusoidal. The resulting Fourier analysis is more difficult to interpret compared with classical Fourier analysis. Wavelet analysis is very useful in analyzing and describing time series with gradual frequency changes. Wavelet analysis also has a shortcoming by giving no exact meaning to the concept of frequency because wavelets are not periodic functions. In addition, the two analysis methods above require equally-spaced time series observations.
In this paper, by using a sequence of periodic step functions, a new analysis method, adaptive Fourier analysis, and its theory are developed. These can be applied to time series data where patterns may take general periodic shapes that include sinusoids as special cases. Most importantly, the resulting adaptive Fourier analysis does not require equally-spaced time series observations.

Large amounts of hydrated cement are accumulated on construction site due to improper storage and become a problem which requires getting rid of it. The objective of this investigation is to prepare a good cement from hydrated cement which is useful as a binding material, the effect of hydrated cement content as a partial replacement of cement on compressive strength and volume change of different mixes is studied. The investigation also extends to evaluate the structural performance of clay brick walls built from cement-hydrated cement mortar as a binding material, and to evaluate the effect of type of mortar, eccentricity and number of courses on compressive strength of clay brick prisms and to find the ultimate strength of load bearing clay brick walls and compare the experimental values of the ultimate strength of the wall with predicted values. The experimental results show that using hydrated cement as a partial replacement of cement up to 30% can be made without significant change in compressive strength compared with control mix.

In this work, an analytical model is presented to show the air leakage effect on the heat transfer within a permeable 120 mm thick, fiber glass wall. Both steady-state and steady periodic conditions are considered for the inner and the outer surfaces of the wall. Computer calculations are made to determine the temperature profiles and heat flux variations within the wall taking into consideration the infiltration and exfiltration of air. The effect of air flows on the heat transmission through the wall is studied and the thermal advantages of the circulating air through the building walls are analyzed.
The study is concentrating on the thermal performance of dynamic walls integrated in a whole building, as a function of the infiltration and exfiltration rates and the building thermal load. The results indicate that the dynamic walls can save energy of up to 20 percent of the total building thermal load

Besides the fast development in the technology of the electronics world, there is another development in the concepts and principles of antenna work. This paper presents mathematical expressions for the main features of the cross-field antenna CFA, like electric field E, magnetic field H, and the Poynting vector S. These expressions are basically derived by considering the principle of two point charges in the space throw measuring the potential at far point, leading to the electric field and magnetic field forms of CFA.

The system of treatment depends on studying the properties of material found in the Iraqi environment called Siliceous Rocks. Laboratory analyses showed that materials were free of any harmful substances to consumers. These materials were used with and without alum for treatment raw water has different artificial turbidities ranging between low and high turbidity. Results indicate improvement in turbidity removal by about 35% when using Porcelanite Rocks with aluminum ion for treated samples that have medium and high turbidities (60, 120 NTU). Also, contributions of positive ions were stated in the treated water through different mechanisms, the percent of missing of calcium ions was 50%. There was an increase in pH with the addition of the small amount of Porcellanite Rocks that will shift pH to optimum limits (7-8) for the operation of Aluminum Hydroxide.

This research includes developing a computer program to improve the water quality of the third river-northern section by maintaining the EC and SAR values within the allowable limits for irrigation. This has been suggested to be done by the construction of desalination plants on the drainages along the river, operating with a minimum cost to achieve the desired pollutant limit. The influence of drainage changes and the maximum limit of pollutants at cost is also considered in this program.