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Analytical solution for nonlinear interaction of euler beam resting on a tensionless soil

The nonlinear interaction between an elastic Euler beam and a tensionless soil foundation is studied. Exact analytical solutions of the challenging problem are rather complicated. The basic obstacle is imposing compatibility conditions at lift-off points. These points are determined as a part of the solution although being needed to get the solution itself. In the current work, solutions are derived using the approximate Rayleigh-Ritz method. The principal of vanishing variation of potential energy is adopted. The solution is approximated using a set of suitable trial functions. Lift-off

Energy and Water
Mechanical Design

Experimental investigation of the dynamic characteristics of wrapped and wound fiber and metal/fiber reinforced composite pipes

This paper experimentally investigates the effect of the manufacturing method and metal reinforcement option on the natural frequency and damping behavior of five polymer and Fiber Reinforced Polymer (FRP) composite pipes. The five pipes are made of polymer, roll-wrapped woven glass FRP, metal-reinforced roll-wrapped woven glass FRP, filament-wound glass FRP, and metal reinforced filament-wound-up glass FRP. The composite pipes can replace conventional pipes in oil and gas industries and conventional metallic shafts in many applications. Logarithmic decay, logarithmic decrement, and random
Energy and Water
Mechanical Design

Ergonomic analysis of a working posture in steel industry in Egypt using digital human modeling

This study presents solutions for improving a bending awkward posture in steel industry in Egypt using digital Human Modeling (DHM). The information is gathered by interviewing the workers, working postures are recorded via a video camera while the worker is performing his usual work. The postures are analyzed using DHM software. Porter comfort analysis and Rapid Upper Limb Assessment are applied for postures analysis. The analysis shows high levels of discomfort in neck, trunk, leg and forearm. These discomforts could cause permanent injuries over long periods. A modified design is proposed

Healthcare
Mechanical Design

Modeling complex flow induced by water waves propagation over submerged square obstacles

Submerged breakwaters are efficient structures used for shore protection. Many design features of these structures are captured upon modeling wave propagation over submerged square obstacles. The presence of separation vortices and large free surface deformations complicates the problem. A multiphase turbulent numerical model is developed using ANSYS commercial package. Careful domain discretization is done employing suitable mesh clustering to capture high gradients. Various numerical model parameters are provided, including grid size and time step. Special attention is directed towards

Energy and Water
Mechanical Design

Analysis of Tapered Timoshenko and Euler-Bernoulli Beams on an Elastic Foundation with Moving Loads

This research studies the vibration analysis of Euler-Bernoulli and Timoshenko beams utilizing the differential quadrature method (DQM) which has wide applications in the field of basic vibration of different components, for example, pillars, plates, round and hollow shells, and tanks. The free vibration of uniform and nonuniform beams laying on elastic Pasternak foundation will be studied under three sets of boundary conditions, that is, mixing between being simply upheld and fixed while utilizing the DQM. The natural frequencies and deflection values were produced through the examination of
Energy and Water
Software and Communications
Mechanical Design

Tandem Organic Solar Cell Optimization Using Response Surface Methodology

Organic solar cells have many advantages such as their ease of manufacturing, flexibility, and low cost compared to perovskite and silicon solar cells. However, increasing their power conversion efficiency (PCE) is still challenging. In this paper, response surface methodology of design of experiments (DOE) is used to optimize the PCE of a tandem organic solar cell. The cell is based on boron sub-phthalocyanine to reduce the series resistance between the layers. The optimization process is performed by formulating an empirical polynomial regression model relating the PCE to the active layers'

Energy and Water
Mechanical Design

The effect of the geometric and thermal parameters on the thermal stresses during the passive cooling of printed circuit boards

The effect of components' thermal properties in addition to their geometric configuration on the developed thermal stress in a model printed circuit board (PCB) is investigated. This effect is quantified through three parameters, the average normalized temperature gradient, maximum normalized temperature gradient and the uniformity factor. It is found that the effect of the geometric configuration, especially that of the heat-generating component, is more significant than the thermal properties of the components. © 2019 IEEE.

Energy and Water
Mechanical Design

Controller Design and Optimization of Magnetic Levitation System (MAGLEV) using Particle Swarm optimization technique and Linear Quadratic Regulator (LQR)

Magnetic Levitation System is one of practical examples which faces some nonlinearities behavior. Such systems require special types of controller parameters consideration for accurate results. In this paper, the process of tuning is to determine the system poles and getting them away from the instability region using state feedback (SF) controller methodology. The resulted controllable system parameters are estimated using LQR controller. Since the desired goal is to minimize vital parameters in the system behavior like the steady state error, settling time, raising time of the system and

Circuit Theory and Applications
Mechanical Design

Gray Wolf Optimization of Fractional Order Control of 3-Omni Wheels Mobile Robot: Experimental Study

Committing robotics with artificial intelligence becomes mandatory collaboration with distinct environments. Omnidirectional Wheeled (Omni-WD) mobile robots are one of the robots that interact with humans in various circumstances, where it is important to function effectively and accurately. In this paper, the distinction of a 3WD-Omni model and control using machine vision is demonstrated. The use of fractional order (FO) calculus has been stated to increase the degrees of freedom of the controller over the integer ones. Hybridization of FO control and metaheuristics optimization is reported

Artificial Intelligence
Circuit Theory and Applications
Mechanical Design

Fabrication of bio-plastic composite pellets from agricultural waste and food waste

This study aims to produce starch bioplastic pellets from food waste such as potato peels. Measuring the ease of flow of the melt is crucial for producing these pellets. The melt flow index (MFI) is measured in this study to evaluate the consistency of the produced pellets and determine the extent of degradation of the plastic because of molding. This study investigates the effect of adding different fillers to the starch matrix on reducing the MFI value. The fillers used in this work are nano chitosan, nano potato peel, and micro cellulose fillers. The fillers were used with different
Agriculture and Crops
Mechanical Design