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.
Surfactants with capability to bind to organics might modify reaction network in hydrothermal carbonization (HTC), probably affecting the properties of resulting hydrochar and/or derived activated carbons (AC). This was studied herein by conducting HTC of tangerine peel (TP) at 200 °C in the presence of cetyltrimethylammonium bromide (CTAB) or sodium dodecyl sulfate (SDS) and further activation of hydrochar with ZnCl2 at 550 °C. The results indicated that CTAB may have interacted with intermediates containing oxygen-containing functionalities (i.e. -OH, C=O and C-O-C), potentially suppressing polymerization reactions and reducing hydrochar yield by 24.6% with hydrochar-blank as a base for comparison. In-situ IR measurement confirmed highly aliphatic nature of the hydrochar-CTAB, which facilitated development of porous structures in activation, producing AC of much higher SBET and pore volume (1726.9 m2g-1 and 1.24 cm3g-1) than that from AC-char-Blank (1245.8 m2g-1 and 0.83 cm3g-1). In comparison, SDS presence generated electronegative micelle structures serving as seeds for formation of hydrochar, which increased significantly yields of hydrochar (70.4% versus 40.3%) by wrapping SDS-derivatives inside the hydrochars. The SDS-derivatives could not be activated by ZnCl2, producing AC of lower SBET (1067.7 m2g-1). However, cracking of the SDS-derivatives increased abundance of mesopores by nearly 3 folds.
High entropy alloys (HEAs) have become the focus of research and industrial attention as a new class of advanced engineering materials due to their exceptional properties and performance. Generally, HEAs exhibit superior performance compared to traditional alloys, especially when they form FCC or BCC single-phase solid solutions. However, achieving such systems is beyond simple mixing of elements and is not always straightforward. It strongly depends on element selection, deliberate design of compositions, processing strategies, and thermodynamic control. Given the vast compositional space of HEAs, the use of predictive tools is Inevitable. Phase formation rules, as an empirical approach, have become effective and valuable tools for accelerating the screening of single-phase FCC or BCC alloys and minimizing trial-and-error efforts due to their low cost, time-saving nature, and simplicity. In this regard, the present review elaborated quantitatively and conceptually the thermodynamic parameters such as Gibbs free energy of mixing (ΔGmix), configurational entropy (ΔSmix), enthalpy of mixing (ΔHmix), and the prediction parameter for solid solution formation (Ω), along with Hume-Rothery criteria, including atomic size difference (δ), valence electron concentration (VEC), and electronegativity difference (Δχ). In addition, the processing and manufacturing routes, economic aspects, and applications of HEAs are discussed. This review provides a comprehensive overview of HEA with a practical framework from element selection, design, and fabrication techniques to the relationship between phase, properties, and performance. The present work bridges the gap between HEAs design, manufacturing processes, practical implementation, and application. Additionally, an overview of cost and manufacturing considerations has highlighted future research directions in targeted design, scalable production, and the industrial application of HEAs.
Aquaculture is developing in many countries to meet the rising protein demand associated with a rapidly growing human population. However, intensification of production brings with it challenges such as deteriorating water quality and increasing disease outbreaks. These conditions lead to an increased risk of infectious diseases and led to higher mortality rates, which causes economic losses. Lactococcosis, particularly that caused by the Gram-positive bacterium Lactococcus garvieae, is one of the most common of these problems and can cause significant losses in various fish species. The intensive use of antibiotics for control purposes creates additional risks in terms of antimicrobial resistance, environmental pollution, and food safety. Therefore, natural feed additives have gained importance in recent years. Certain additives that support immune responses and increase disease resistance in fish have become prominent. Among these, phytobiotics, probiotics, prebiotics, and synbiotics are the most well-known and effective. Their widespread availability, lower cost, and environmental safety make these additives considered an alternative approach to aquaculture. Studies show that these additives strengthen both innate and adaptive immune responses, reduce infection severity, and reduce mortality associated with L. garvieae infections. However, there are still gaps in knowledge regarding how these substances regulate mechanisms such as the immune system, inflammatory processes, antioxidant defenses, and interactions with pathogens. This review aims to clarify these mechanisms by bringing together scientific data obtained in recent years. It also discusses how the information obtained can contribute to the development of safer feed additive strategies and the development of new vaccine approaches. This aims to support the establishment of a more sustainable production structure in the aquaculture sector.
The Ti3AlC2 MAX phase exhibits excellent properties such as high electrical conductivity, toughness, and machinability. In this work, Ti3AlC2 MAX phase was synthesized via spark plasma sintering (SPS) with a high purity of 97.9
