The University of Bonab was previously a faculty of the University of Tabriz, Iran, and now, since 2011, is an independent University located in Bonab. The institute has ten technical departments — electrical engineering, computer engineering, civil engineering, mechanical engineering, optical engineering, architectural engineering, Textile engineering and so on. About 3000 students study there.University of Bonab offers over 20 B.Sc programs in engineering and more than 100 graduate programs of engineering, science, and high technology. A central lab facility serves the research needs of the university as well. Dormitories distinctly for men and women in two on-campus and off-campus buildings serve students all year round. Contributing to the great diversity of university of Bonab's academic staff are academicians with Ph-D’s obtained all around the world as well as in other top universities in IRAN.
Introduction and Objectives: Functionally graded materials are an advanced class of composites which their microstructure change continuously in a specific direction. The main purpose of this paper is to study the microstructure of the Al-13.8 wt.% Mg2Si eutectic alloy produced by centrifugal and gravity casting methods and comparison the effect of addition of Al-5Zr inoculant on the changes in their casting microstructure. Materials and methods: In this research, with gravity and centrifugal casting of Al-13.8wt.% Mg2Si alloy and adding an appropriate amount of Al-5Zr inoculant, microstructural changes in the radial direction of the casting cylinder were compared with gravity casting samples. The chemical composition and microstructural characteristics of the samples were studied using energy-dispersive X-ray spectroscopy and optical microscopy, respectively. Results: The microstructure of the centrifugally cast Al-5Zr inoculant-free cylinder exhibited columnar Al/Mg2Si eutectic cells along the radial direction, accompanied with an accumulation of primary Mg2Si particles in the inner layer of the cylinder. Upon the addition of Al-5Zr inoculant, the morphology of Mg2Si secondary phases changed from cubic to Chinese script shape. However, the microstructure of the conventional gravity casting sample containing and without zirconium showed Al/Mg2Si eutectic cells without a specific targeted distribution, an accumulation of primary and light Mg2Si particles in the upper layer of the casting cylinder, which is due to the separation of these particles against the upward direction of gravity. Conclusion: The microstructure of the cast cylinder processed by centrifugal casting containing Al-5Zr inoculant showed a targeted distribution of Al/Mg2Si eutectic cells and aggregation and reduction in the size of Mg2Si particles in the inner radial layer of the cast cylinder.
A key challenge in developing fiber–wireless (FiWi) access networks is determining the optimal positions of optical network units (ONUs) to maximize network performance and minimize development costs. This paper introduces backtracking search-based weighted fuzzy C-means (BWFCM), an optimized unsupervised method for ONU placement in FiWi. The proposed method integrates the local refinement strength of weighted fuzzy C-means (WFCM) with the global exploration capability of the power mutation-based backtracking search algorithm (PBSA). It is enhanced by an adaptive weighting mechanism that dynamically balances load imbalance and average communication distance without manual parameter configuration. The objective is to minimize the average Euclidean distance between ONUs and their primary wireless users while ensuring fair load distribution. Extensive simulations on standard test cases demonstrate BWFCM’s superiority over state-of-the-art ONU placement algorithms, including chaotic local search-based Levy flight distribution (CLSLFD), Harris-Hawks optimization (HHO), marine predators algorithm (MPA), and arithmetic optimization combined with fuzzy c-means (AOFCM). BWFCM achieves competitive load balance across all test cases and reduces the total combined cost compared to its counterparts, with the minimum improvement (0.24%) over MPA and the maximum (12.17%) over HHO. Scalability and complexity analyses confirm BWFCM as a tractable, competitive, and parameter-free solution for ONU placement in next-generation broadband access networks.
This study investigated the effect of fiber type on the mechanical behavior of sandwich composite structures with a rubberized cork core. The specimens were fabricated using Kevlar/epoxy and glass/epoxy as face sheets, while a low-density, energy-absorbing rubberized cork was used as the core material in all samples. The manufacturing process was carried out through hand lay-up, followed by pressing and oven curing to ensure proper bonding and final mechanical strength. To evaluate the mechanical performance, the samples underwent standard three-point flexural and low-velocity impact tests. The flexural test results indicated that although both types of composites exhibited suitable elastic behavior in the initial stages, their ultimate flexural strength was relatively low, with failure occurring under moderate loads. In impact tests, Kevlar/epoxy face sheet samples demonstrated higher impact resistance and suffered relatively less damage, whereas glass/epoxy samples showed greater vulnerability and experienced larger deformations. Analysis of force-time, force-displacement, and energy absorption curves revealed that the cellular structure of cork played a crucial role in preventing full penetration and effectively absorbing part of the impact energy.
This study investigates the catastrophic failure of a connecting rod from a 2.4-L four-cylinder engine using an integrated experimental and numerical methodology. The three-dimensional geometry of the connecting rod was developed in CATIA and imported into ANSYS Workbench for static structural and fatigue finite-element analyses under realistic engine operating conditions. The applied loads were calculated based on combined gas pressure and inertia forces, resulting in a peak cyclic load of approximately 23.6 kN. Numerical results revealed a pronounced stress concentration, minimum fatigue life, and maximum damage accumulation at the big-end fillet region. Mechanical testing confirmed that the connecting rod steel exhibits high strength and ductility (UTS ≈ 965 MPa, elongation ≈ 18
This study demonstrates the significance of coupling biomass valorization with accelerated carbonation curing (ACC) as an integrated strategy for low-carbon construction materials. A bio-based ternary binder incorporating wood sawdust with shale ash, steel slag, and a reduced proportion of ordinary Portland cement (OPC) was developed to simultaneously enhance mechanical performance and enable CO2 sequestration. The optimized formulation (25% shale ash, 15% OPC, 10% slag, and 50% sawdust) achieved a compressive strength of 7.2 MPa and an elastic modulus of 6 GPa, exceeding the performance of comparable wood-cement composites while using substantially less clinker. Microstructural analyses (SEM, XRD, FTIR, and XPS) confirmed portlandite depletion and the formation of calcite and low-Ca/Si C-(A)-S-H phases under ACC, resulting in matrix densification. Life cycle assessment (EN 15804 +A2) indicated a 65% reduction in greenhouse gas emissions relative to OPC-based systems, highlighting the combined structural and environmental benefits of the proposed approach.
