Arabian Journal for Science and Engineering最新文献

Intelligent control systems developed for production facilities significantly contribute to production efficiency and quality. Using intelligent control systems has now become a necessity in iron and steel sintering plants that produce millions of tonnes annually. Automatic control of the sinter machine speed, which directly affects production efficiency and quality, is one of the first issues to be addressed. The complexity of the sintering process, being affected by many variables, and the nonlinearity of these variables make it difficult to control the machine speed. This study demonstrates that we have overcome this challenge using a fuzzy logic controller (FLC), which is optimized with an adaptive neuro-fuzzy inference system (ANFIS). The FLC we have designed operates with the characteristic point of the thermal state, the mixture level, the vacuum average, and the current speed parameters. We achieved an average success rate of 95%. The developed system automatically controls the speed of the sinter machine with high accuracy, independent of the operator. The system we have developed is used continuously at the Iskenderun Iron & Steel Co. sinter plant. The results obtained from the production facility show that the developed system captures the thermal change in the sinter pallet and manages the machine accordingly, increases the sintering efficiency by at least 10%, and ensures process safety. These results revealed that the developed system can be used effectively in the iron and steel industry and the use of the system will increase efficiency.

Benzocaine is known for its antibacterial, anticancer, antitumor, and antifungal properties. Herein, a series of three new Schiff bases is synthesized by reacting benzocaine with salicylaldehyde (E4AS), 2,3-dihydroxybenzaldehyde (E4ADH), and 5-chlorosalicylaldehyde (E4ACl). These benzocaine-based Schiff bases were characterized by a variety of spectroscopic methods, including FTIR, NMR, (¹H and ¹³C), and elemental analysis (CHN). Additionally, the single crystal X-ray diffraction method was used to reveal the molecular structures of the derivatives. Solid-state X-ray crystal structures of E4AS and E4ACl adopted enol tautomeric form, whereas keto-tautomeric form was found in E4ADH. The supramolecular assembly of the compounds was probed by Hirshfeld surface analysis. The void analysis was executed to predict the mechanical response of the compounds. Additionally, UV–Vis spectroscopy and molecular docking practices were used to look into the DNA binding abilities of the benzocaine-based Schiff bases. The geometries of the molecules were fully optimized and studied for their electronic structural properties of respective compounds. The frontier molecular orbitals and molecular electrostatic potentials were studied to predict the properties of molecules. The study provides molecular-level intuitions into the synthesis and prospective uses of these Schiff bases in the arena of general and medicinal chemistry.

This study presents the design and implementation of a PLC microprocessor adhering to the IEC-61131-3 standard, executed on a Cyclone V FPGA using a DE10-NANO development board. Our microprocessor optimizes the central processing unit by streamlining the data path, achieving a remarkable simulated response time of approximately 60 ns, equivalent to three clock cycles at a 50 MHz frequency for Boolean operations. To substantiate our approach, we conducted practical experiments utilizing a FESTO conveyor station, employing relays as actuators, and incorporating optical and inductive sensors. The results underscore the feasibility of our proposed approach and serve as practical validation of its efficacy. This work introduces a promising avenue for the development of cost-effective PLCs employing SoC FPGA variants. Additionally, a thorough comparison of execution times with other early reported architectures. Our microprocessor outperforms even well-established PLCs like the S7-312, with substantial reductions in execution times of 94.54% for floating-point operations, 71.42–93.33% for word operations, and up to 78.57% for bit operations.

Alcohol oxidase (AOX) oxidizes alcohols to produce carbonyl compounds and peroxides. Its promoter (P_AOX1) is widely used in methylotrophic yeasts. A promising yeast expression system (Pichia sp. strain SO) was developed for bacterial lipase expression regulated by P_AOX1 of Komagataella phaffii (previously known as Pichia pastoris). However, its unidentified AOX gene and the protein structure have deterred the search for the best inducer. This study was aimed to identify the yeast species and determine the best inducer for P_AOX1 upregulation using in silico AOX protein analysis. Morphological (scanning and transmission electron microscopies) and carbon assimilation analyses confirmed isolate SO as Meyerozyma guilliermondii (previously known as Pichia guilliiermondii). Using Hidden-Markov model and degenerate PCR, the LCAO gene (2091 bp) was discovered in M. guilliermondii strain SO. The enzyme, MgFAO1 shared 14% similarity to K. phaffii AOX1 protein (KpAOX1). Molecular docking of MgFAO1 three-dimensional structure predicted using AlphaFold2 showed its preference toward long-chain 1-dodecanol as the substrate unlike KpAOX1 (short-chain methanol). While the alcohol-binding pocket in MgFAO1 was more hydrophobic compared to KpAOX1, 1-dodecanol could be a better inducer for protein expression in M. guilliermondii strain SO. Thus, in silico pipeline employed in this study can help identify homologous proteins in other expression hosts and their preferred substrates for promoter upregulation. However, the computational analyses were merely predictions and further wet-lab validation is required. Yet, this strategy allows cost-efficient screening of potential inducers for microbe-based protein production in the industries, reducing the production cost and offering cheaper options for consumers.

By improving the understanding of fluid behaviour and allowing the development of cutting-edge technologies that enhance fluid-related processes in various sectors, advances in fluid dynamics serve a crucial role in both science and engineering. Sequel to the broad applicability of fluid dynamics leading to more efficient, sustainable, and innovative solutions for real-world challenges associated with the motion of liquids and gases, reviews of the recent advancements are far-fetched. The scope of the review was structured to focus on recent published facts on lift generation and drag reduction of aeroplanes, Computational Fluid Dynamics, turbulence modelling, and multiphase flow. Research synthesis which focuses on summarizing the state of the art of research facts on fluid dynamics was adopted. It is worth concluding that fluid dynamics principles stand as a cornerstone, unequivocally driving the relentless advancement of aerospace and automotive engineering, crucially contributing to the development of drag reduction techniques, precision control of lift generation, streamlined shapes for drag minimization, innovative wing profiles for enhanced lift, and effective boundary layer control for drag reduction. Recent advancements in Computational Fluid dynamics have revolutionized engineering simulations, providing unparalleled accuracy and efficiency in modelling complex fluid flow phenomena, from aerodynamics to hydrodynamics, thereby significantly accelerating the design and optimization processes across various industries. Studying of multiple fluid phases moving through a system simultaneously causes complicated interactions, phase transition events, and a variety of flow patterns, making it a complex but essential research topic. Experts face challenges validating Computational Fluid Dynamics results due to insufficient experimental data.

Natural fibre-reinforced hybrid polymer composites have gained significant attention worldwide in mechanical, aerospace, and automotive applications. Advanced machining techniques, such as abrasive water jet machining, have emerged as a solution to various challenges in this field, offering benefits such as the ability to shape complex geometries, achieve superior performance, improve surface characteristics, and attain high levels of accuracy. The research proposes a new approach for producing biodegradable hybrid composites composed of polylactic acid, bamboo particles, and montmorillonite clay using an innovative solvent-free stir-casting technique optimised for maximum efficiency. To systematically analyse the surface roughness, kerf angle, and material removal rate, a Box–Behnken design of experiments was employed, with the traverse rate, abrasive feed rate, and stand-off distance considered design variables. Analysis of variance was used to determine the significance of the differences between means of variables, while response surface methodology was utilised to establish the explicit relationship between the design variables and the response of the composite machining. The particle swarm optimisation algorithm was also employed to determine the optimal values of the design parameters for machining composites. The results showed that the traverse rate was the most influential factor, followed by the abrasive feed rate. In contrast, the stand-off distance had a relatively lower level of influence. The optimal process parameters were identified, resulting in a minimum surface roughness of 5.56 μm, a kerf taper of 0.0044 radians, and a material removal rate of 1175 g/min.

Poly(lactic acid) (PLA) was injected into test sheets and then dipped in a suspension of xylene and trimethylol propyl silane (95/5) containing titanium dioxide (TiO₂) nanoparticles (NPs) at 65 and 85 °C for 3, 7, 10 and 15 s. TiO₂ NPs aggregates coated the sheet surfaces after dipping. The camera photos and the static water contact angle (WCA) showed that the dip-coating transformed all the hydrophilic surfaces into hydrophobicity, and especially that the sheet with retention of 85 °C and 7 s exhibited superhydrophobicity, while the water droplets on the 65 °C sheets were in pinning state. The water droplets rolled off the superhydrophobic surface at tilt angles below 3°, showing self-cleaning. The retention period of 7 s was suitable, as it achieved the highest surface hydrophobicity regardless the retention temperature. The images of scanning electron microscope (SEM) and optical microscopes demonstrated the deposition of TiO₂ NPs aggregates on the sheet surface and the formation of the porous structure on the surface. The combination of the aggregates with nanoscale protrusions and the pores with nanoscale pore walls constituted a hierarchical structure. The retention temperature of 65 °C made the pores shallow and wide, and the TiO₂ concentration of 2% instead of 1% caused the excessive TiO₂ NPs aggregates to cover the PLA substrate, reducing the WCA. The wetting models of water droplets on the surfaces of the 65 and 85 °C sticks were classified as Wenzel and Cassie states, respectively.

Producing vertical edged parts in sheet metal forming methods can cause tears on the sheet. The incremental forming method can allow sheet forming without tears. Forming can be done multi-stage to prevent this tear. Incremental forming method can be used in prototype production. The most important advantages of incremental forming method are that it is fast and inexpensive. In this study, we applied multi-stage forming to the two-point incremental forming-rolling blank holder method. Thus, we have developed a new way: the multi-stage, two-point incremental forming-rolling blank holder method. Parts with vertical edges are produced, and the wall thickness distribution is examined. The work material is a DC04 sheet with a thickness of 0.98 mm. The workpiece is axially symmetrical with a wall angle of 90°. The effect of four different parameters were researched: increment, feed rate, clamping pressure, and angle increment. Three different levels were determined for each parameter. The wall thickness distribution of the parts obtained from the experiments was measured.

Small wind turbines (SWTs) can generate sufficient electricity to meet the energy needs of developing countries. However, due to the airflow characteristics at low Reynolds numbers and associated issues, specific airfoil designs are crucial to define the blade geometry. In this study, the lift coefficient (CL), stall angle of attack (AoA), and lift-to-drag coefficient ratio (CL⁄CD) of S1048, S3021, and S5010 airfoils and then optimized shapes with various thickness-to-camber ratio percentages (t/c%) were analyzed using XFOIL software to optimize their suitability for SWT applications. The aerodynamic efficiency of the optimized airfoils in terms of CL, drag coefficient (CD), CL/CD, and stall AoA was evaluated across Reynolds numbers ranging from 50,000 to 500,000. The findings revealed that these modified airfoils exhibited peak CL⁄CD values surpassing those of their baseline airfoils for the Reynolds number range of 50,000–500,000. The magnitudes of these improvements varied for each airfoil and at different Reynolds numbers. Additionally, the geometric modifications in terms of t/c% applied to the S1048, S3021, and S5010 airfoils resulted in enhanced maximum CL and stall AoA across all analyzed Reynolds numbers.

The increasing demand for electrical energy, the limitation of fossil fuel resources, and the aggravation of environmental pollution have made it inevitable to use clean energy sources, such as wind energy. In the meantime, the doubly fed induction generators are commonly used due to their capability of controlling the reactive power with no need for capacitor banks. Furthermore, increasing the capacity of wind farms has made the high-voltage direct current (HVDC) transmission network in the form of multiple terminals a preferred option for transferring the power of these sources over long distances. In this situation, the interaction of transmission system controllers with other controllers and devices has become a primary concern of the network. Research has shown that power systems that undergo stress exhibit complex dynamic behaviors that increase the possibility of interaction between system components and can endanger the stability of the power system. The present study attempted to investigate the problem of interaction in multi-terminal HVDC transmission systems, and the problem of torsional interaction in wind farms connected to these transmission systems. The linear modal analysis was used to investigate the interaction, and the analytical results were validated using MATLAB/Simulink time-domain simulation. In addition, due to the change of system parameters over time, this paper comprehensively investigated the system damping over different system parameters, and a structured scheme was employed to obtain an optimal range of control coefficients, ensuring the stable operation of the system.