The research addressed an analytical field investigation of the locality of meander, the factors responsible of the locality of the meander at certain points of the stream other than others, and the role sequence of these factors in the formation process.
The research revealed that the location of forming the meander was associated closely with the scale structural composition of the bank materials from which the first stage of forming the curved stream, for the inhomogeneous or non-identical opposite banks in their scale structural composition saw an activity of differential corrosion, while the homogeneous and identical opposite banks in their scale structural composition saw an identical corrosion activity in its intensity at both banks. The research investigated in field the presence of scale variation of the materials of opposite banks in the location of forming the meander which was not found at the incurved stream banks by taking samples and analyze them in scale. The analysis results showed that the synclinal bank was with high sand ratio which was the reason behind the activity of corrosion process due to its weak cohesion, high permeability, and highroughness creating an environment of frequent turmoil reverse eddy currents. As to its opposite bank which represented the convex bank, the results of the scale analysis showed its soil to be with high content of mud; therefore, it was resistant to the corrosion activity compared to the synclinal bank, being more cohesive and of weak permeability, it was soft, so it did not create a turmoil eddy motional environment of the aquatic currents. While in the incurved stream, the results of the scale analysis showed that the soil of both opposite banks were identical in its volume content; therefore, the activity of the corrosion process was identical at both banks and its high sand ratio resulted in the expansion of the stream and not its fold.
The research revealed that the circularity of the curved stream imposed the presence of the centrifugal force which appeared in the domains of the circular motion, changing the concentration locations of the currents. As it is well-known, the fastest currents in the river are those which locate far away from the bottom and the banks, and are found in the middle of the stream which we really found in the incurved stream, but due to the control of the centrifugal force, we found that the fastest currents were concentrated at the synclinal banks and that the slowest currents were concentrated at the synclinal banks, which explains logically and realistically due to the contrast of the corrosion and sediment activity in the curved river streams and the presence of centrifugal force was responsible of the development of these streams from fold to curve to turn to cut lake.
The research defined the morphology of the curved stream at any stage of the development stages at the presence of three corrosion units that represent the synclinal banks meeting three sedimentary units represent the convex banks, two of which were opposite to each other represent overall the neck of the stream and the stream in its complete shape was represented by the overall of these corners
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Accurate calculation of transient overvoltages and dielectric stresses from fast-front excitations is required to obtain an optimal dielectric design of power components subjected to these conditions, which are commonly due to switching and lightning, as well as utilization of power-electronic devices. Toroidal transformers are generally used at the low voltage level. However, recent investigations and developments have explored their use at the medium voltage level. This paper analyzes the model-based improvement of the insulation design of medium voltage toroidal transformers. Lumped and distributed parameter models are used and compared to predict the transient response and dielectric stress along the transformer winding. The parameters
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This article presents the results of an experimental investigation of using carbon fiber–reinforced polymer sheets to enhance the behavior of reinforced concrete deep beams with large web openings in shear spans. A set of 18 specimens were fabricated and tested up to a failure to evaluate the structural performance in terms of cracking, deformation, and load-carrying capacity. All tested specimens were with 1500-mm length, 500-mm cross-sectional deep, and 150-mm wide. Parameters that studied were opening size, opening location, and the strengthening factor. Two deep beams were implemented as control specimens without opening and without strengthening. Eight deep beams were fabricated with openings but without strengthening, while
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There is an interesting potential for the use of GFRP-pultruded profiles in hybrid GFRP-concrete structural elements, either for new constructions or for the rehabilitation of existing structures. This paper provides experimental and numerical investigations on the flexural performance of reinforced concrete (RC) specimens composite with encased pultruded GFRP I-sections. Five simply supported composite beams were tested in this experimental program to investigate the static flexural behavior of encased GFRP beams with high-strength concrete. Besides, the effect of using shear studs to improve the composite interaction between the GFRP beam and concrete as well as the effect of web stiffeners of GFRP were explored. Encasing the GFRP
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In this study, a three-dimensional finite element analysis using ANSYS 12.1 program had been employed to simulate simply supported reinforced concrete (RC) T-beams with multiple web circular openings subjected to an impact loading. Three design parameters were considered, including size, location and number of the web openings. Twelve models of simply supported RC T-beams were subjected to one point of transient (impact) loading at mid span. Beams were simulated and analysis results were obtained in terms of mid span deflection-time histories and compared with the results of the solid reference one. The maximum mid span deflection is an important index for evaluating damage levels of the RC beams subjected to impact loading. Three experi
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Abstract: A novel design of Mach Zehnder Interferometer (MZI) in terms of using special type of optical fiber that has double clad with graded distribution of the refractive index that can be easily implemented practically was suggested and simulated in this work. The suggested design is compact, rapid, and is simple to be modified and tested. The simulated design contains a MZI of 1546.74 nm of central wavelength that is constructed using special type of double clad optical fiber that has two different numerical apertures. The first aperture will supply single mode propagation via its core, while the second numerical aperture supports a zigzag wave propagation (multimode) in the first clad region. The interferometer’s
... Show MoreHeuristic approaches are traditionally applied to find the optimal size and optimal location of Flexible AC Transmission Systems (FACTS) devices in power systems. Genetic Algorithm (GA) technique has been applied to solve power engineering optimization problems giving better results than classical methods. This paper shows the application of GA for optimal sizing and allocation of a Static Compensator (STATCOM) in a power system. STATCOM devices used to increase transmission systems capacity and enhance voltage stability by regulate the voltages at its terminal by controlling the amount of reactive power injected into or absorbed from the power system. IEEE 5-bus standard system is used as an example to illustrate the te
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