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Abstract Accurate flood forecasting in advance is crucial for planning and implementing watershed flood prevention measures. This study developed the PSO–TCN–Bootstrap flood forecasting model for the Tailan River Basin in Xinjiang by integrating the particle swarm optimisation (PSO) algorithm, temporal convolutional network (TCN), and Bootstrap probability sampling method. Evaluated on 50 historical flood events from 1960 to 2014 using observed rainfall-runoff data, the model showed, under the same lead time conditions, a higher Nash efficiency coefficient, along with lower root mean square and relative peak errors in flood forecasting. These results highlight the PSO–TCN–Bootstrap model’s superior applicability and robustness for the Tailan River Basin. However, when the lead time exceeds 5 h, the model’s relative peak error remains above 20%. Future work will focus on integrating flood generation mechanisms and enhancing machine learning models’ generalisability in flood forecasting. These findings provide a scientific foundation for flood management strategies in the Tailan River Basin.

As electronics become more powerful and compact, laminated microchannel heat sinks (MCHSs) are essential for handling high heat flux. This study aims to optimize the MCHS design for improved heat dissipation and structural strength. An orthogonal experiment was established with the average surface temperature of the heat source as the evaluation metric, and the optimal structure was determined through simulation. Finally, cooling uniformity, fluidity, and performance evaluation criterion (PEC) analyses were carried out on the optimal structure. It was determined that the optimal combination was the triangular cavity microchannel (MCTC), with a microchannel width of 0.5 mm, a microchannel distribution density of 60%, and the presence of surface undulation on the microchannels. The result shows that the optimal structure’s peak inter-layer stress is just 34.8% of its longitudinal tensile strength. Compared to the traditional parallel straight microchannel (MCPS), this structure boasts an 8.6 K decrease in the average surface temperature and a temperature variation along specific paths that is only 9.9% of that in traditional designs. Moreover, the optimal design cuts the velocity loss at the microchannel entrance from 75% to 59%. Thus, this research successfully develops an effective optimization strategy for MCHSs.

The complementary combination of emphasizing target objects in infrared images and rich texture details in visible images can effectively enhance the information entropy of fused images, thereby providing substantial assistance for downstream composite high-level vision tasks, such as nighttime vehicle intelligent driving. However, mainstream fusion algorithms lack specific research on the contradiction between the low information entropy and high pixel intensity of visible images under harsh light nighttime road environments. As a result, fusion algorithms that perform well in normal conditions can only produce low information entropy fusion images similar to the information distribution of visible images under harsh light interference. In response to these problems, we designed an image fusion network resilient to harsh light environment interference, incorporating entropy and information theory principles to enhance robustness and information retention. Specifically, an edge feature extraction module was designed to extract key edge features of salient targets to optimize fusion information entropy. Additionally, a harsh light environment aware (HLEA) module was proposed to avoid the decrease in fusion image quality caused by the contradiction between low information entropy and high pixel intensity based on the information distribution characteristics of harsh light visible images. Finally, an edge-guided hierarchical fusion (EGHF) module was designed to achieve robust feature fusion, minimizing irrelevant noise entropy and maximizing useful information entropy. Extensive experiments demonstrate that, compared to other advanced algorithms, the method proposed fusion results contain more useful information and have significant advantages in high-level vision tasks under harsh nighttime lighting conditions.

The lack of trace element iron has become a key factor restricting vegetable yield and quality improvement. To address the low production efficiency of water–fertilizer coupling in agricultural production, we used a combination of experimental research, theoretical analysis, and mathematical modeling to systematically determine the effects of magneto-electric water irrigation with iron application on spinach growth and physiology, its yield and quality, and soil water transport characteristics. Compared with conventional water irrigation, under magneto-electric water irrigation, the water volume and applied iron concentration average increased the total accumulation of nitrogen, carbon, and iron in the aboveground part of spinach by 3.71%, 10.16%, and 14.14%, respectively, and the aboveground part of spinach had the highest total accumulation of nitrogen and carbon when irrigation water was 3300 m3 ha−1 and iron fertilizer application at 0.15%. Additionally, magneto-electric water irrigation increased spinach aboveground fresh weight and soluble sugar and protein content by an average of 13.34, 18.26, and 11.61%, respectively. Based on a comprehensive quantitative evaluation and analysis of aboveground nutrient accumulation in spinach, aboveground fresh weight, water use efficiency, and soluble sugar and protein content, we determined the optimal irrigation water and iron fertilizer application for spinach growth.

The problem of poor water and fertilizer retention in sandy soils can lead to physiological growth restriction and yield and quality decline in apples. Sodium carboxymethyl cellulose (CMC) formula can improve the soil structure and increase the water- and fertilizer-holding capacity of the soil, and Biogenic Stimulant (BS) can improve the drought stress resistance of crops and promote the physiological growth of crops. Considering that CMC and BS may improve the physiological characteristics of sandy soil apples, in this study, CMC was coupled with BS in sandy apples, and the effects on the physiological characteristics, yield, and quality of apples were systematically investigated. The results showed that CMC and BS could increase leaf N, P, and K content, with the greatest increases seen in the Y2C2 treatment (9.28, 0.61, and 0.56 g kg−1, respectively) compared with the CK treatment. The SPAD values of leaves following the coupled CMC and BS treatment compared to the CK treatment were elevated in the range of 4.47–24.29% at the flowering and fruiting stage, 2.84–26.50% at fruit expansion stage, and 6.64–19.41% at maturation stage. In the light response data of different treatments, the maximum net photosynthetic rate occurred in the Y2C2 treatment, and the net photosynthetic rate, transpiration rate, and stomatal conductance were all the highest in the Y2C2 treatment during the fruit expansion stage, with the net photosynthetic rate being higher than that of the CK treatment by 5.09 µmol m−2 s−1. The combination treatments of CMC and BS increased apple yield by 10.69 to 27.62% as compared to the CK treatment, and also increased soluble reducing sugar, soluble solids, and VC and reduced the titratable acid content. There was no correlation between the SPAD value during fruit expansion (p > 0.05) and the other physiological indexes (p < 0.05). Through the established functional relationship between the application rate of CMC and BS and apple yield, the recommended BS application rate of 27 kg ha−1 and CMC application rate of 20.625 kg ha−1 could yield up to 43,357.8 kg ha−1.

The power detection of the distribution network is essential for reliable and secure distribution. In this paper, a flexible dual-threshold SVDD fault warning algorithm with fault samples is proposed to deal with problems concerning complex network topology, accessible data, and missing fault data in the power grid. For the problems of complicated network topology and a wide variety of signal types, we propose to combine wavelet packet energy features with Spearman to extract electric signal features, and finally achieve accurate feature extraction of multiple signal types. In the case of the problems of untimely judgement and low accuracy of the original SVDD, a relaxed SVDD fault warning algorithm with fault samples is correspondingly proposed. We turn the original SVDD boundary into a double-layer boundary, and divides the hypersphere space into three regions to increase the sensitivity to the fault samples and lessen the risk of missed detection. Besides, an adaptive update strategy is developed, which reduces the computational effort of the model and is proven more applicable to the distribution. Finally, the method is applied to numerical examples and fault detection experiments, and the experimental results in turn verified its effectiveness and superiority.

An interesting phenomenon that yielding was observed in the Ti matrix composites with above 4.10vol%TiCp. To clarify the underlying nature, in-situ tensile test was performed, and results indicated that this was caused by cracking at the interface between the aggregated TiCp and Ti matrix, which is quite different from the well-accepted viewpoint. Furthermore, fracture of stronger TiCp prior to weaker TiBw was also found during in-situ tensile test, and a fracture criterion was proposed from the viewpoint of load transfer.

Three kinds of Cu-Ni-Al alloys, whose chemical compositions are located in the Cu-rich corner of the isothermal section of the Cu-Ni-Al ternary phase diagram, were prepared by melting and casting firstly, and then solution and aging treatments were carried out. The microstructure was characterized and the competitive formation process of Ni-Al intermetallics were discussed. The results show that there are little amounts of NiAl phase at the grain boundary and needle- or particle-like Ni3Al phase inside the Cu matrix in all the as-cast alloys, although they are in the single-phase area. Solution and aging treatments mainly result in the disappearance and precipitation of Ni3Al phase, but the precipitations during aging are much smaller than those in the as-cast alloys. Thermodynamics and kinetics calculation indicate that the NiAl intermetallic wins out in the solidification process because of its lower change in Gibbs free energy, while Ni3Al phase is first to precipitate during aging due to its lower formation enthalpy and required Al concentration. The most important contribution of this work is that it proves that intermetallics can precipitate from the so-called single-phase zone in the Cu-rich corner of the Cu-Ni-Al phase diagram, which is the necessary prerequisite for the realization of high strength and high electrical conductivity.

For better clarifying the influence of processing factors on the forming quality of the direct powder rolling (DPR) process, finite element simulation based on the modified Drucker–Prager/Cap (DPC) model was established and the key physical parameters of the powder were confirmed by experimental measurements. Subsequently, the effect of the main factors in the DPR process, viz., powder gradation, rolling speed and rolling gap, on the density and morphology of a green sheet were discussed by using an orthogonal experiment design followed by experimental verification. The influence of DPR parameters on the density of the green sheet is examined by a range analysis, which can reflect the sensitivity of influencing factors to the forming quality of the green sheet. The larger the range value is, the more sensitive the influencing factor is. This suggests that the quality of the green sheet is mainly influenced by particle gradation. The results show that the density of the resulting DPR green sheet with optimal parameters is mainly 7.5~8.0 g/cm3, reaches 80% of the theoretical density, and the mechanical strength can also afford the transferring process of the green sheet for the next sintering craft. The methods for modeling, obtaining physical parameters and the numerical simulation results can be used to guide rapid formation of the metal sheet by using direct powder rolling craft.

Severe plastic deformation (SPD) was carried out on AZ80 alloy by high-pass multi-directional forging (MDF). Results showed that AZ80 alloy was effectively refined through MDF, and average grain size was refined to 0.73 µm after 24 passes of forging. Its tensile strength, yield strength and elongation reached 333.8 MPa, 233.7 MPa and 17.8%, respectively, which were 1.22 times, 1.35 times and 2.54 times of those before the forging. When the MDF was less than 6 passes, the coarse grains were mechanically divided and refined, and a small amount of recrystallized grains appeared in the deformation band and its cross zone. When the MDF was more than 6 passes, grain division, recrystallization nucleation and grain growth occurred simultaneously, the microstructure refinement was slowed, and the uniformity was improved continuously. The heating between forging passes mainly caused restoration in the early forging, and the static recrystallization refinement in the middle of forging. In the later stage of forging, the grain growth caused by static recrystallization and the grain refinement caused by the deformation canceled out, and the microstructure no longer continued to refine with the increase of the forging pass. Keywords: High-pass multi-directional forging, AZ80 magnesium alloy, Ultrafine grain, Severe plastic deformation

Cu-Ni-Si alloys have been widely used in electronics and electrical industries.The preparation method of alloy was not limited to smelting, powder metallurgy method has also attracted the attention of many researchers. In this study, Cu-Ni-Si alloys were prepared using hot-pressed sintering and elemental copper powders, in which nickel and silicon powders were used as raw materials. The results show that, when the Cu-Ni-Si alloys were prepared using hot-pressed sintering, there were no Ni-Si intermetallic compounds except the δ -Ni _2 Si phase in the microstructure of alloys. After the ageing treatment, when the mass ratios of Ni/Si were 2:1 and 3:1, the precipitation of δ -Ni _2 Si phase was significantly less. However, when the mass ratios of Ni/Si were 4:1 and 5:1, the precipitation of δ -Ni _2 Si phase particles increased significantly. The results from electrical conductivity and Vickers hardness show that, after the ageing treatment, both the electrical conductivity and Vickers hardness of the alloys greatly improved.

Hot compression tests of Cu-Ni-Si alloy with high Ni and Si contents were performed at the deformation temperatures of 750–950 °C, and the strain rates of 0.01–10 s−1 on a Gleeble-3800 thermo-mechanical simulator. The critical conditions for dynamic recrystallization (DRX) of Cu-Ni-Si alloy were obtained by processing the collected data and combining with the inflection point of θ-σ curve with the minimum value criterion of −∂θ/∂σ-σ curve. There was a certain correlation between the critical strain (εc) and the peak strain (εp), that was, εc/εp = 0.723, and the functional relationship between εc and Z parameter was εc = 1.05 × 10−3Z0.059. The average recrystallized grain size under various deformation conditions was measured, and the DRX grain growth model of Cu-Ni-Si alloy was established as dDRX = 5650.4ε̇−0.12891exp(−73142/RT). Keywords: Cu-Ni-Si alloy, Dynamic recrystallization, Critical condition, Grain growth model

A Cu–Ni–Si alloy with high Ni and Si contents was prepared by the traditional melting and casting method, and then multiple forging and ageing were conducted to investigate their effect on the microstructure and properties. The results show that reticular Ni _31 Si _12 phases are located on the grain boundaries of the dendritic α -Cu(Ni, Si) solution matrix in the as-cast Cu–Ni–Si alloy because of the high Ni and Si contents, and some rice-like Ni _2 Si phases precipitate in the interior of α -Cu(Ni, Si) grains during cooling. With increasing number of forging passes, the morphology of the α -Cu(Ni, Si) matrix changes from dendrites to elongated dendrites and then equiaxed grains, the Ni _31 Si _12 phase changes from reticular to irregular and then particle-like, while the Ni _2 Si phase gradually disappears. As a result, the hardness increases continuously up to 18 forging passes, while the electrical conductivity first increases and then decreases significantly. The hardness and electrical conductivity achieve the highest values with 18 forging passes and a subsequent ageing treatment at 450 °C for 4 h, and the corresponding microstructure comprises an equiaxed α -Cu(Ni, Si) matrix with microscale Ni _31 Si _12 particles and sub-microscale Ni _2 Si precipitates.

Cu–Ni–Si alloys with 94 wt% Cu content and different Ni/Si mass ratios were prepared by hot pressing sintering, and then solution treatment and ageing treatment were also performed. Microstructure and phase composition along with electrical conductivity and hardness of the alloys under different treating condition was studied, and then the influence of Ni/Si mass ratio was discussed. Results showed that the as-sintered Cu–Ni–Si alloys mainly consisted of α -Cu matrix and some Ni _31 Si _12 particles at the grain boundary as well as δ -Ni _2 Si phases inside the matrix. After solution treatment, most of the Ni–Si compounds decomposed, but δ -Ni _2 Si precipitates from the matrix after ageing treatment. With increasing Ni/Si mass ratio, the electrical conductivity and hardness of the alloys increases firstly and then decreases, while a highest combination of them achieved when the mass ratio of Ni/Si was 4:1. The effect of Ni/Si ratio on the electrical conductivity of Cu–Ni–Si alloys can be mainly ascribed to the residual content of Ni/Si in the Cu matrix after ageing treatment. When the mass ratio of Ni/Si is equal to the atomic ratio of δ -Ni _2 Si phase, most of the Ni and Si atoms would precipitates as δ -Ni _2 Si, and then the electrical conductivity reaches the highest value.

This paper explores the physical properties and pyrolysis characteristics of rice husk combustion in air and in argon. The SEM results show that the outer epidermis of combusted RHIR (rice husk in air) is well organized with features that include papillae shapes and full, straight, high ridges. The inner epidermis of the RHIR has long rectangular furrow tissues. The results also show that the outer epidermis of pyrolyzed RHR (rice husk in argon) has ridges that are not as straight as for the RHIR and the top of the papillae have small holes. The inner surface of the RHR looks a some cracked. XPS analysis shows that the surfaces of RHIR and RHR contain carbon, oxygen, and silicon. The carbon was found to be in the elemental graphite form, the oxygen in the −2 oxidation state, and the silicon in the Si4+ form as SiO2. The DSC graphs have “camel peaks”, showing that an increase in rate of heating leads to an increase in the exothermic peaks. Calculations show that, initially, increased temperature leads to increased activation energy for pyrolysis, but as the temperature continues to increase, the activation energy decreases again. The frequency factor follows the same trend. In analysis of carbon content, rice husk volatile carbon content is the largest, it is about 33.94%, especially 700 °C, the carbon content of volatile minimum is about 0.33%. Keywords: Rice husk, Microstructure, Thermal analysis, Thermal properties, XPS