Search Results (557)

A case study of designing a waste dump was conducted for the iron mine located in the Bulacan area, Philippines. Iron ore mines generate a relatively high amount of waste, and at the study mine, the constrained waste dumping area of 3 hectares necessitated a higher dump design, leading to potential stability issues. Additionally, the waste dump is projected to be situated on an inclined surface; subsequently, there is a concern about dump stability. Therefore, this study aims to find the optimum waste dump design by assessing its stability, and a geometrical configuration was conducted to optimize the bench parameters. Numerical modeling of the finite difference method (FDM) was used to estimate the distribution of the Factor of Safety by simulating several models. Models with steeper base inclinations (>12°) demonstrate progressive instability, as demonstrated by pre-assessment. The statistical analysis results show that the total model simulations with a 45-degree slope angle have a significantly high probability of failure of 38.2%. Whereas models with 35-degree and 40-degree slope angles have probabilities of failure calculated as 0.3% and 6.5%, respectively. Therefore, results suggest that the general slope angle should be kept at 40 degrees or less. Moreover, the results show that an average of 0.02 points drops in FoS for each 2.5 m of increment in dump height. Regarding geometrical setup, four benches with 7.5 m of berm would be preferable for the waste dump design of the case study. Overall, the effect of an inclined surface as a base was discussed, the effect of a gradual increase in dump height was outlined, and the significance of the dump slope angle on dump design was highlighted. Full article

An enhanced snow geese algorithm (ESGA) is proposed to address the problems of the weakened population diversity and unbalanced search tendencies encountered by the snow geese algorithm (SGA) in the search process. First, an adaptive switching strategy is used to dynamically select the search strategy to balance the exploitation and exploration capabilities. Second, a dominant group guidance strategy is introduced to improve the population quality. Finally, a dominant stochastic difference search strategy is designed to enrich the population diversity and help it escape from the local optimum by co-directing effects in multiple directions. Ablation experiments were performed on the CEC2017 test set to illustrate the improvement mechanism and the degree of compatibility of their improved strategies. The proposed ESGA with a highly cited algorithm and the powerful improved algorithm are compared on the CEC2022 test suite, and the experimental results confirm that the ESGA outperforms the compared algorithms. Finally, the ability of the ESGA to solve complex problems is further highlighted by solving the robot path planning problem. Full article

This research focuses on creating CuO/PANI nanocomposite films by electrodepositing copper oxide nanoparticles into a polyaniline matrix on ITO substrates. The CuO nanoparticle content was adjusted between 7% and 21%. These nanocomposites are promising for various applications, such as optoelectronic devices, gas sensors, electromagnetic interference shielding, and electrochromic devices. We utilized UV-Vis spectroscopy to examine the nanocomposites’ interaction with light, allowing us to ascertain their refractive indices and absorption coefficients. The Scherrer formula facilitated the determination of the average crystallite size, shedding light on the material’s internal structure. Tauc plots indicated a reduction in the energy-band gap from 3.36 eV to 3.12 eV as the concentration of CuO nanoparticles within the PANI matrix increased, accompanied by a rise in electrical conductivity. The incorporation of CuO nanoparticles into the polyaniline matrix appears to enhance the conjugation length of PANI chains, as evidenced by shifts in the quinoid and benzenoid ring vibrations in FTIR spectra. SEM analysis indicates that the nanocomposite films possess a relatively smooth and homogeneous surface. Additionally, FTIR and XRD analyses demonstrate an increasing degree of interaction between CuO nanoparticles and PANI chains with higher CuO concentrations. At lower concentrations, interactions were minimal. In contrast, at higher concentrations, more significant interactions were observed, which facilitated the stretching of polymer chains, improved molecular packing, and facilitated the formation of larger crystalline structures within the PANI matrix. The incorporation of CuO nanoparticles resulted in nanocomposites with electrical conductivities ranging from 1.2 to 17.0 S cm⁻¹, which are favorable for optimum performance in optoelectronic devices. These results confirm that the nanocomposite films combine pronounced crystallinity, markedly enhanced electrical conductivity, and tunable band-gap energies, positioning them as versatile candidates for next-generation optoelectronic devices. Full article

Endogenous inhibitors can inhibit seed germination, and GA₃ can promote seed germination. Whether GA₃ can affect the changes in endogenous inhibitors has not been clarified. In order to study the effect of GA₃ on the endogenous inhibitors in sainfoin (Onobrychis viciifolia) seeds, the systematic separation method and gas chromatography–mass pectrometry (GC-MS) method were used to determine the endogenous inhibitors using cabbage (Brassica rapa var. glabra Regel) as a bioassay model to validate the inhibitory activity in sainfoin seeds, and then the optimal concentration of GA₃ was determined to promote seed germination. The results showed that endogenous inhibitors existed in the pod coat, seed coat, and seed embryo of sainfoin seeds, with the methanol and ethyl acetate phases showing the highest degree of inhibition. The organic compounds were mainly organic acids, phenols, lipids, and alkanes. The levels of changes in germination indicators, storage substances, and antioxidant enzymes determined that 600 mg/L GA₃ was the optimum concentration to promote germination of sainfoin seed. It was also found that 600 mg/L GA₃ reduced the relative content of endogenous inhibitors and changed the content of endogenous hormones. In summary, the presence of endogenous inhibitors may be one of the reasons for the low germination rate of sainfoin seeds, with 3-methoxycatechol and 4-nitrosodiphenylamine playing a major role. GA₃ can reduce the relative content and types of endogenous inhibitors to promote the germination of sainfoin seeds. Our experimental results provide the basis for subsequent exploration of the mechanism of specific endogenous inhibitors and the identification of deeper molecular mechanisms. Full article

This study proposes a synergistic treatment method for BOF slag and copper slag via oxidation–magnetic separation, with the dual goals of preparing MgFe₂O₄ magnetic material and stabilizing the non-magnetic slag. The effects of copper slag addition, the oxidation temperature and the oxidation time on the phase transformation and MgFe₂O₄ morphology during the oxidation process are investigated. The results show that copper slag addition can release the simple iron oxides of FeO and Fe₂O₃ from iron-containing phases from BOF slag and copper slag, promoting the synthesis of MgFe₂O₄. Furthermore, the oxidation temperature and oxidation time have a significant influence on the size of the MgFe₂O₄ particles. To obtain the MgFe₂O₄ magnetic material, the optimum oxidation parameters were used, with an oxidation degree of Fe²⁺ of 95.85% and a yield of MgFe₂O₄ of 90.31%. In addition, the main phase of non-magnetic slag was Ca₂SiO₄, and both free CaO and free MgO from BOF slag were eliminated, indicating a potential application in construction materials. This technology maximizes resource utilization and the valorization of metallurgical solid waste. Full article

The study of vibration isolation devices has become an emerging area of research in view of the extensive damage to buildings caused by earthquakes. The ability to effectively isolate seismic vibrations and maintain the stability of a building is thus addressed in this paper, which evaluates the effect of horizontal ground excitation on the response of a structure isolated by a coupled isolation system consisting of a non-linear damper (QZS) and a friction pendulum system (FPS). A single-degree-of-freedom system was used to model structures whose bases are subjected to seismic excitation in order to assess the effectiveness of the QZS–FPS coupling in reducing the structural response. The results obtained revealed significant improvements in structural performance when the QZS–FPS system uses a damper of optimum stiffness. A 30% reduction in displacement was recorded compared with QZS alone for two signals, one harmonic and the other stochastic. The response of the QZS–FPS system with soft stiffness to a harmonic pulse reveals amplitudes reaching around eight times those of the pulse at low frequencies and approaching zero at high frequencies. In comparison, the rigid QZS–FPS coupling has amplitudes 0.9 and 3.5 times higher than those of the harmonic signal. Thus, the resonance amplitudes observed for the QZS–FPS system are lower than those reported in other studies. This analysis highlights the performance differences between the two types of stiffness in the face of harmonic pulses, underlining the importance of the choice of stiffness in vibration management applications. The stochastic results show that on both hard and soft soils, the new QZS–FPS system causes structures to vibrate horizontally with maximum amplitudes of the order of 0.003 m and 0.007 m respectively. So, QZS–FPS coupling can be more effective than all other isolators for horizontal ground excitation. In addition, the study demonstrated that the QZS–FPS combination can offer better control of building vibration in terms of horizontal displacements. Full article

In the current work, two novel tandem-based tuned mass damper configurations are introduced. These configurations extend the recently proposed tuned tandem mass damper inerter (TTMDI) by replacing the linking dashpot with an inerter (i.e., the inerter-connected TTMDI (ICTTMDI)), and an integrated tuned tandem mass damper inerter (I-TTMDI) by integrating recently proposed tuned tandem mass damper (TTMD) configurations. The control efficiency of the optimally designed dampers for a single-degree-of-freedom (SDOF) system was evaluated in a uniform framework to reveal and compare the performances of the ICTTMDI and I-TTMDI with those of other recently proposed tandem-based configurations. The optimum design of all the studied configurations was determined by the particle swarm optimization (PSO) algorithm. The evaluation of the performances included the effectiveness in the frequency domain and that of the norm and maximum reduction in the displacement and absolute acceleration in the time domain under 21 earthquake records with different characteristics. Additionally, the strokes of the dampers, the structure energies, and the power spectral densities (PSDs) of the responses were investigated. The optimum design of the I-TTMDI revealed the best configuration by determining the optimum distributions of the mass and inertance between the tandem mass and inerter links, respectively. The proposed configuration not only demonstrated improved response reduction across the displacement and acceleration measures but also maintained remarkable robustness under 21 earthquake records (far-fault, near-fault forward-directivity, and fling-step records). Furthermore, the advantages of the side inerter distribution were particularly effective at widening the operating frequency band, breaking through the traditional limitations of TMD-based devices. The consistent performances of the newly proposed configurations prove that they can be used to advance the development of more reliable structural control systems. Full article

Selecting appropriate locations of emergency centers is an important issue in avoiding probable damages by natural disasters. Emergency rescue sites are constructed to provide emergency supplies swiftly for people in affected areas. Factors of transportation fluency and road damage degrees should be considered, which largely affect rescue efficiency. In order to find appropriate sites accurately, we proposed a redesigned method Variable Butterfly Optimization Algorithm (VBOA), based on the Butterfly Optimization Algorithm, by adding the Variation Operator mechanism to avoid the limitations of local optimum problems present in other optimization algorithms. The Variation Operator effectively combines both global and local search strategies to improve the performance of global searching, and it accelerates the convergence speed of the algorithm. We conducted our experiment on selected candidate sites with multiple optimization methods; the experiment results demonstrate that our proposed method maintains the balance between conditions of coverage area and expenditure. Our proposed method relieved the reliance of local optimum results and achieved better convergence accuracy in our selected samples in comparison with other methods both in initial and later siting phases. Full article

A significant portion of energy consumption in buildings is allocated to heating, with substantial losses resulting from inadequate insulation, poor sealing, and thermal bridging. While proper insulation plays a crucial role in mitigating these losses, determining its optimal thickness is essential to reduce energy consumption and increase energy efficiency. This study employs life cycle cost analysis and average heating degree day values to calculate the optimum insulation thickness for 81 provinces in Türkiye. The findings highlight the absence of a one-fits-all insulation solution, emphasizing the need for customized approaches tailored to specific conditions that consider specific factors, such as environmental conditions, heating sources, costs, economic parameters and the materials used. Proper insulation application is projected to reduce carbon emissions by 90% and lower annual heating costs by approximately 65%. These energy efficiency improvements are particularly significant for both households and businesses, enhancing profitability and competitiveness. Collaborative efforts to promote proper insulation solutions are anticipated to reallocate financial resources toward innovation and contribute to long-term business sustainability. This study provides an important framework for guiding the adoption of proper insulation practices in building design and construction. Full article

Fatigue-induced crack initiation and propagation are a major concern in pearlitic railway rails and wheels. Rails and wheels undergo significant plastic deformation on their near-surface layers during service, leading to the initiation and propagation of cracks within the deformed region. Existing models typically use finite element models (FEMs) to describe these kinds of fatigue phenomena. However, they fail to establish a strong connection between the microstructure of the undeformed and the deformed materials and their corresponding fatigue properties. Therefore, a model based on the soft-contact discrete element method (DEM) was developed that considers microstructural details such as prior austenite grains (PAGs), pearlite blocks, pearlite colonies, and lamellar orientation of the ferrite–cementite structure of the pearlite. The Voronoi Tessellation method was used to generate a hierarchical mesh to represent these microstructural details, considering the distribution of microstructural details. Crack propagation is simulated by applying damage laws on the microstructural interface level that degrade the stiffness of the fibers connecting the mesh elements. The model’s crack growth predictions are compared with experimental results from the literature to validate its accuracy for different deformation degrees. The developed model can be used in the designing and material selection phase in the railway industry to help select the material with optimum microstructural features. Also, it can be used for the selection of the optimum heat treatment process considering materials resistance to the fatigue crack growth. Full article

The scarcity of in situ observation stations and the unreliability of long-term satellite data necessitate the use of reanalysis datasets to study elevation-dependent climate change (EDCC) in the third pole (TP) region. We analyzed elevation-dependent temperature and precipitation patterns over TP using the ECMWF Atmospheric Reanalysis Fifth Generation (ERA5), a global reanalysis product with coarse resolution, along with three high-resolution regional reanalysis datasets that cover our study domain: Indian Monsoon Data Assimilation and Analysis (IMDAA), High Asia Refined Analysis—Version 2 (HAR-v2), and Tibetan Plateau Regional Reanalysis (TPRR). Comparing the performance of the four reanalysis datasets in capturing EDCC over TP is crucial, as these datasets provide spatially and temporally consistent data at an optimum resolution that greatly aids EDCC research. Our study results reveal the following: (1) A positive elevation-dependent warming trend is observed across all four datasets in winter and autumn, with varying magnitudes of warming across the datasets. (2) All four datasets exhibit positive elevation-dependent wetting trends in all seasons, except autumn. These are primarily driven by pronounced drying trends at lower elevations and relatively minimal changes in precipitation trends at higher elevations. (3) ERA5 and IMDAA exhibit similar results in capturing elevation-dependent climate change, whereas the TPRR dataset reveals more extreme and unique features in temperature trends compared to the other three datasets. HAR-v2 shows smaller variations in temperature and precipitation trends across different elevations and seasons, in contrast to the other three datasets. While all reanalysis datasets indicate EDCC in the TP, their varying degrees of seasonal and spatial differences underscore the need for a careful evaluation before using them as reference data. Comparison of reanalysis datasets with available observational records, such as in situ measurements and satellite data, over overlapping spatial and temporal domains is essential to assess their quality. This evaluation can help identify the most suitable reanalysis dataset, or combination of datasets, to serve as reliable a reference even in regions or periods without observational data. Full article

Laying hens’ metabolism goes through a cyclic process to produce eggs, which requires higher dietary protein and energy in the morning (AM) and higher calcium (Ca) in the afternoon/evening (PM) than the rest of the day. Therefore, poultry scientists are trying to adopt a new feeding strategy called AM/PM or split feeding to precisely meet hen’s requirements more effectively than conventional methods. A 10-week cage layer trial was carried out via a Box–Behnken response surface design to identify the optimal amount of protein, energy, and calcium of the AM/PM diets. There were 13 test treatments with three levels of crude protein (19.6%/18.4%, 20.3%/17.7%, 21%/17%), calcium (3.3%/4.9%, 2.5%/5.7%, 1.6%/6.6%), and apparent metabolizable energy (AME) (12 MJ/kg/11.2 MJ/kg, 12.4 MJ/kg/10.8 MJ/kg, 12.8 MJ/kg/10.4 MJ/kg) for AM/PM diets respectively and a control treatment with industry baseline (CP-19%, Ca-4.1% and ME 11.6 MJ/kg). These are the calculated values of nutrients on a dry matter basis. A total of 364 hens were randomly distributed into 2 dietary treatments where each treatment had 13 replicates (2 hens per replicate cage, 26 hens per treatment). AM and PM diets were swapped out at approximately 8 am and 4 pm each day. Egg production and hen performance were measured daily and weekly, respectively, with egg quality, serum Ca, and nutrient digestibility measured at week 10. AM:PM intake and feed cost were calculated for each treatment. The optimal FCR, feed cost, and AM:PM intake were used to determine Ca, CP, and AME levels. The result showed that 6 out of 13 of our test treatments gave improved FCR compared to the control treatment (p = 0.017). Dietary treatments did not affect overall hen weight and serum Ca and egg quality at week 10, except for the lower yolk color score in the control treatment (p = 0.002). Hens in the experimental treatment, with calcium levels of 1.6% and 6.6%, crude protein (CP) levels of 19.6% and 18.4%, and AME content of 12.4 MJ/kg and 10.8 MJ/kg in the AM and PM diet, respectively, showed the highest apparent protein digestibility (56.6%) compared to the control group (p < 0.05). Similarly, hens receiving a treatment containing calcium at 3.3% and 4.9%, CP at 21% and 17%, and AME at 12.4 MJ/kg and 10.8 MJ/kg in the AM and PM diet, respectively, achieved the highest calcium digestibility (62.13%), while the control treatment yielded the lowest calcium digestibility (p < 0.05). After analyzing the data using the Box–Behnken response surface methodology, we found that (21/17)% CP, (3.3/4.9)% Ca, and (12/11.12) MJ/kg energy in the AM/PM diet gave the optimum performance in terms of lower feed cost and better feed efficiency. The data of AM:PM intake demonstrate that selective feeding occurs in between treatments (p < 0.001) and the degree of selection depends on the difference between the level of nutrients in AM and PM diet. This study revealed that when optimized, AM/PM feeding improves feed efficiency and egg quality of laying hens. Full article

The external walls of a building represent the interface between the interior and exterior environments. Insulating external walls represents the most cost-effective means of ensuring indoor comfort. Despite the prevailing assumption that insulation will increase the cost of the building, this study has demonstrated that this is not the case. Notwithstanding the increase in investment costs, the application of insulation to the external walls has been demonstrated to result in a reduction in fuel consumption and operating costs. In accordance with TS 825, there are five distinct degree-day zones, with the requisite heat loads in these zones exhibiting variability. Accordingly, a cost-based methodology is required to ascertain the optimal insulation thicknesses for the various degree-day zones. In this study, the gains to be obtained in the case of using three different insulation materials for five different wall types to be used in the buildings to be built instead of the buildings destroyed in the earthquake in Turkey in 2023 were analyzed. Samples from three degree-day zones affected by earthquakes were assessed for insulation, wall structures, and fuel types. The study assesses optimum insulation thickness, investment cost, annual fuel savings, annual economic benefits, and investment payback period. Full article

Pumpkin seed proteins (PSPs) are a promising resource for obtaining bioactive peptides but their low solubility hinders enzymatic hydrolysis, reducing yield and bioactivity. In addition, enzymatic processes require specific conditions and long processing times; improving the efficiency of this process is essential to expand its industrial applications. In this context, using a high-frequency, low-intensity ultrasound (US) has proven to be an effective strategy for optimizing the hydrolysis of plant protein. This study evaluated the US-assisted (38 W/L, 40 kHz) and conventional hydrolysis of pumpkin seed proteins (PSPs) for 180 min at 25 °C, 40 °C, and at the optimum temperature condition for each enzyme studied (60 °C for Brauzyn^®, 55 °C for Flavourzyme^®, and 50 °C for Neutrase^®), as well as the impact of this process on the macrostructural and functional characteristics of the hydrolysates obtained. The degree of hydrolysis (DH) was significantly higher in US-assisted reactions, reaching increases of up to 57.7% with Neutrase^® at 40 °C. The US also positively influenced the protein solubility of the hydrolysates, especially at pH levels close to the isoelectric point, with improvements of up to 100%, compared to the hydrolysates obtained from the conventional reaction. The antioxidant activity was also enhanced by the US, compared to the conventional reaction, emphasizing the hydrolysates obtained through the action of Flavourzyme^®, which showed increases of 52.4% and 42.6% in the scavenging of DPPH and ABTS radicals, respectively. The analysis of the mean particle size revealed significant reductions with the US (<26.2%). Consequently, the polydispersity index (PDI) demonstrated greater uniformity in the particles obtained from the US-assisted reactions (reductions of up to 20.3%). UV-Vis spectroscopy and intrinsic fluorescence also indicated possible alterations in the tertiary structure of the peptides obtained, mainly in US-assisted reactions. Therefore, US-assisted PSP hydrolysis resulted in better enzymatic performance and produced protein hydrolysates with bioactive potential for food applications. Full article

The implementation of sodium-ion batteries for renewable energy storage requires the development of sustainable electrode materials. Usually, these materials are produced through complex energy-intensive processes that are challenging to scale and involve expensive and/or toxic reagents. In this study, sustainable hard carbon materials, some doped with iron, synthesized from sucrose using a simple, fast, and cost-effective two-step eco-friendly process, are investigated as anodes for sodium-ion batteries. The influence of physicochemical and structural material properties on electrode reversible capacity, cycling stability, and efficiency is analyzed. The SC900 material, which exhibits a certain development of graphite-like structure, though not strictly graphitic, showed the best electrochemical performance, providing discharge capacities exceeding 100 mAh g⁻¹ after 400 cycles with excellent cycling stability and high coulombic efficiency. The capacity of the materials increases as d₀₀₂ decreases, (i.e., as the degree of structural order increases), to the optimum value of ~0.3700 nm. However, a further decrease in d₀₀₂ to values characteristic of quasi-graphitic materials, as a consequence of the catalytic effect of iron, hinders Na⁺-ion storage, which, in addition to the low electrochemical activity of the iron oxides present, leads to much lower capacities. Full article