Farag Mahel Mohammed

Additive manufacturing (AM), particularly Fused Deposition Modeling (FDM), has revolutionized polymer-based fabrication through design freedom and material efficiency. This work presents a comprehensive statical optimization of FDM parameters affecting the flexural properties of acrylonitrile/butadiene/styrene (ABS) specimens. The effects of layer thickness (0.15–0.25 mm), infill density (30–70%), printing speed (35–95 mm/s), and build orientation (Flat, On-edge, Vertical) were investigated following ASTM D790 standards. A Taguchi L9 orthogonal array coupled with ANOVA analysis was employed to quantity parameter significance. According to the ANOVA analysis, infill density was identified as the most influential parameter, accounting for 61.3% of the variation in flexural strength (σ_f) and 60.1% in flexural modulus (E_b). The optimal configuration (0.25 mm layer thickness, 70% infill, 65 mm/s speed, horizontal orientation) yielded a flexural strength of 84.9 MPa and modulus of 2.54 GPa. Microstructural observations confirmed that higher infill and moderate speed improved interlayer fusion and reduced void formation. The developed Taguchi–ANOVA framework offers quantitative insights for tailoring process–structure–property relationships in polymer-based additive manufacturing.

The article discusses how Kudryashov's proposed self-phase modulation scheme and nonlinear chromatic dispersion cause the evolution of quiescent optical solitons in magneto-optic waveguides. Provide a comprehensive understanding of the governing model; generalised temporal evolution is considered. The modified sub-ODE approach is employed to facilitate the recovery of such solitons. This leads to a complete range of optical solitons and the necessary conditions that must be met for these solitons to exist, which are also provided.

The hydraulic elevator is both a cost-effective system and results in extremely clean building exterior lines since the usual penthouse-type machine room is eliminated. Without the need for wires, counterweights, or pulleys, this elevator can transfer people between levels. One of the most significant factors to consider when designing people's elevators is that they should not be disturbed when going between levels and that the elevators should stop accurately. As a consequence, innovative technologies such as the electro-hydraulic servo system (EHSS) may be employed with a traditional hydraulic elevator. This technology may employ speed and position input to provide the desired degrees of speed control, riding comfort, and leveling precision. The EHSS is a closed-loop control system that operates as a drive unit, raising and lowering the elevator cabin in response to a variable like position, velocity, or force. This paper examines various types of hydraulic systems for lifting purposes, as well as the application of servo system principles to hydraulic control valves, to credibly provide the traditional hydraulic elevator with a selectable diversity of precise and smooth transport characteristics across floors. This study also looks at how elevators employ telescopic hydraulic cylinders efficiently for lift purposes in the elevator.

The effect of brake pad wear on the electromechanical disc brake system response using MATLAB/Simulink software was investigated in this paper. The analysis of the pad wear involves building thermal model and electromechanical brake model, and calculating the required braking force at a constant and variable coefficient of friction between the pad and disc. A comparison between the electromechanical brake responses without wear and during wear at a constant and variable coefficient of friction was carried out. The results show that the coefficient of friction has a major role in calculating the required braking force, and cumulated wear during breaking. The required braking force starts higher in the case of using a variable coefficient of friction by about 0.06%. The variable coefficient of friction presents higher wear than the constant coefficient of friction by about 30%.