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In this paper, a multi-strategy fusion enhanced Honey Badger algorithm (EHBA) is proposed to address the problem of easy convergence to local optima and difficulty in achieving fast convergence in the Honey Badger algorithm (HBA). The adoption of a dynamic opposite learning strategy broadens the search area of the population, enhances global search ability, and improves population diversity. In the honey harvesting stage of the honey badger (development), differential mutation strategies are combined, selectively introducing local quantum search strategies that enhance local search capabilities and improve population optimization accuracy, or introducing dynamic Laplacian crossover operators that can improve convergence speed, while reducing the odds of the HBA sinking into local optima. Through comparative experiments with other algorithms on the CEC2017, CEC2020, and CEC2022 test sets, and three engineering examples, EHBA has been verified to have good solving performance. From the comparative analysis of convergence graphs, box plots, and algorithm performance tests, it can be seen that compared with the other eight algorithms, EHBA has better results, significantly improving its optimization ability and convergence speed, and has good application prospects in the field of optimization problems. [ABSTRACT FROM AUTHOR]

Subwavelength‐structured metasurfaces working in visible and near‐infrared bands present a high challenge in large‐scale device fabrication. In this study, a scalable, high‐efficient, and low‐cost laser‐induced nanopatterning technique is exploited to fabricate a kind of short‐range disordered metagratings, which enables broadband polarization‐independent absorption in the visible to near‐infrared wavelength. The short‐range disorder of the laser‐induced nanogratings originates from the laser‐induced thermal effect and can be spontaneously organized during laser nanopatterning. The unique disorder can break the unidirectional characteristics of the nanogratings, which empowers the metagratings to excite coupled resonance modes. This helps to achieve near‐perfect absorption in the visible to near‐infrared band (400–1100 nm) with an excellent angular tolerance (up to 60°) and average absorptivities of 96.3% and 93.5% under the TM and TE modes, respectively. These low‐cost metagratings can potentially inspire wide applications in the fields of solar cells, sensing, and thermal emitters. [ABSTRACT FROM AUTHOR]

Hierarchical metal grids are proven to be a promising solution for achieving high‐performance flexible transparent electrodes (FTEs) due to their significantly enhanced conductivity without noticeably sacrificing transparency. This work develops a one‐step mask‐free line‐shaped laser lithography by separated pulse laser ablation to efficiently fabricate large‐area FTEs composed of hierarchical metal grids, namely microscale grids interconnected with aligned nanowire arrays. The linewidth of aligned wires is highly controllable from the nanometer scale far beyond the diffraction limit (<λ/10) to the micrometer scale. This work experimentally studies the overall performance of FTEs to provide a guideline for selecting the layout and feature sizes of hierarchical metal grids. Hierarchical metal grids with 50 nm nanowires aligned inside the microscale grids show outstanding optoelectronic properties and mechanical stability, with sheet resistance of 4.6 Ω sq−1, transmittance of 82.9%, and a tiny increase in sheet resistance less than 4% after 1000 cycles of bending tests. These results prove that the line‐shaped laser lithography technique is a facile, low‐cost, and high‐throughput fabrication method for high‐performance FTEs. [ABSTRACT FROM AUTHOR]

Laser‐induced periodic surface structures (LIPSS) have become an important avenue towards surface nanopatterning and certain device applications due to their subwavelength feature size and versatility with different materials. However, the uncontrollable non‐uniformity in achievable nanostructures presents a limit towards its practical application. Here, a robust approach is proposed to obtain controllable nanostructures with long‐range order based on a new insight into one of the electromagnetic origins of nonuniformity of LIPSS, namely a half‐periodic mismatched optical enhancement (h‐MOE) effect. The h‐MOE effect originates from the interference enhancement of surface plasmon polaritons (SPPs) located between tips of every two adjacent ripples in laser scanning process. It is found that LIPSS can be self‐aligned and highly controllable if the h‐MOE effect is elaborately modulated through designed laser scanning strategies especially sequential scanning paths. The new laser nanopatterning approach based on h‐MOE demonstrates controllable patterning ability to theoretically infinitely large‐area super‐straight gratings, orientation‐controllable gratings, and half‐periodic mismatched nanohole arrays. [ABSTRACT FROM AUTHOR]

Hierarchical micro/nanostructures have garnered considerable attention for their capabilities in light modulation, but the flexible fabrication of designed optical functional structures at both micro and nano scales remains challenging. Here, a polarization‐modulated patterned laser ablation method complemented by flowing liquid is proposed to fabricate hierarchical microgrooves featuring tunable cross‐sections and engraved surface nanostructures with controllable periods and orientations. The liquid‐assisted ablation counters the shielding effect of ablation debris through laser‐induced microjets, ensuring accurate control of the microgroove's shape by modulating the laser pattern in the focal plane. Simultaneously, the absence of debris also permits the consistent formation of laser‐induced periodic surface structures (LIPSS) across the microgrooves. The LIPSS's period and orientation can be finely adjusted by manipulating the pulse energy and polarization within the patterned laser spot, facilitating the adaptable creation of hierarchical micro/nanostructures for optical application needs. As a demonstration, blazed gratings featuring orientation‐customized LIPSS are fabricated, which exhibit polarization‐dependent diffraction efficiency. The laser fabrication technique offers a highly versatile solution for sculpturing shape‐controllable hierarchical gratings on hard‐to‐machine materials, paving the way for the swift production of customized optical elements. [ABSTRACT FROM AUTHOR]

• Efficiently fabricating hierarchical nanotextured microgrooves through hybrid laser processing. • Producing uniform 1D nanogratings and 2D nanoholes on V-shaped microgrooves. • Laser interference and laser-SPPs interference contribute to the formation of those nanostructures. • Those nanostructures can engrave into many microgrooves within one scanning process. Functional surfaces with hierarchical micro-/nanostructures play a vital role in improving performances in emerging fields over the past decades. In this work, we propose a hybrid manufacturing method for efficiently fabricating hierarchical nanotextured microgrooves by combining fly cutting and femtosecond laser nanopatterning. Nanostructures, including nanogratings and nanoholes, can be uniformly generated in a V-shaped groove by controlling laser polarization. We experimentally study the influence of the laser parameters (laser fluence and effective pulse number) to investigate the morphological evolution of nanostructures in the V-shaped groove under laser irradiation. By theoretical calculations and analyses, we find that the interference between the incident and reflected laser is helpful for ablating the nanogratings. In addition, this interference can also couple with the laser-SPPs (surface plasmon polaritons) interference and form nanoholes. The results enrich the diversity of achievable laser-induced periodic surface structures on complex surfaces and provide a new way to efficiently fabricate large-area hierarchical micro-/nanostructures at low cost. [ABSTRACT FROM AUTHOR]

Large‐scale nanopatterning at low cost and high throughput is crucial to the practical applications of metasurfaces. Phase‐change materials equipped in these metasurfaces as modulation layers or resonators are generally applied to achieve a tunable function and have attracted significant attention. Here, an efficient method is developed by combining ultrafast laser localized modification/ablation and subsequent etching to fabricate nanostructures on a phase‐change material, Ge2Sb2Te5 (GST), over a wafer‐sized area. The localized laser treatments under gradually increased laser fluences contribute to the variety of achievable nanostructures including disk and ring structures, whose feature sizes and periods can be tuned by adjusting laser parameters and subsequent etching conditions. A mid‐infrared metasurface absorber is designed and fabricated by using the GST ring units as resonators. Notably, varying the geometrical features of rings allows generating dual‐band and tri‐band absorption peaks in the mid‐infrared spectral range, whose peak absorptivity can reach ≈92%. By converting GST from amorphous to crystalline state, a broad absorption spectral redshift of 700 nm is achieved. The large‐area high‐throughput fabrication together with high‐absorption design demonstrates their potential in mass production of phase‐change metasurface‐based absorbers. [ABSTRACT FROM AUTHOR]

Metallic nanowires have exhibited paramount importance in achieving functional electrical, electrochemical, and optical performances due to their unique physicochemical properties. Efficient fabrication of the nanowires with controllable geometry and line width is highly required in related applications. Here a new far‐field laser parallel direct writing approach for fabricating nanowire array far beyond the diffraction limit by a modulated vector beam with dual‐peak intensity distribution is reported. Such a modulated beam can perform selective laser ablation to fabricate nanowires, whose line width can be largely reduced by tuning the dual‐peak orientation relative to the laser scanning direction. As a demonstration, a 157 nm‐wide (less than λ/3) gold nanowire, reaching ≈1/20 of the diffraction limit, has been fabricated in far field by using a low numerical aperture microscope objective (NA = 0.1). The nanowire fabrication efficiency is also largely improved by applying multifocal modulated vector beams for parallel processing. [ABSTRACT FROM AUTHOR]

• Long and short lag-time are integrated for runoff forecasting. • Self-attention mechanism is introduced to model temporal dependencies. • The new model outperforms the classic models in daily runoff forecasting. It is still very challenging to enhance the accuracy and stability of daily runoff forecasts, especially several days ahead, owing to the non-linearity of the forecasted processes. Here, we hypothesize that short lag-time has a significant impact on forecasting results. Thus, we incorporate short previous time steps into long short-term memory (LSTM) and develop the Self-Attentive Long Short-Term Memory (SA-LSTM). In SA-LSTM, the self-attention mechanism is used to model interdependencies within short previous time steps. SA-LSTM is evaluated at eight runoff datasets. The experimental results demonstrate that, compared with state-of-art benchmark models, SA-LSTM achieves the best performance. The RMSEs of SA-LSTM are at least 2.3% smaller than that of the second best model at the seventh day. The NSEs and NSE_In of SA-LSTM are at least 4.6% and 6.4% higher than those of the second best model at the seventh day. Furthermore, SA-LSTM also surpasses the baseline methods for base, mean and peak flows. The superiority of SA-LSTM can be attributed to its exploitation of information in short lag-time. [ABSTRACT FROM AUTHOR]

• Multiscale structures were fabricated by hybrid vector beams for the first time. • Shapes of multiscale patterns can be controlled by designing state of polarization. • Polarization ellipticity at arbitrary azimuth angle of hybrid vector beam is deduced. • LIPSS fabricated by hybrid vector beams are rotational symmetric with 90° rotation angle. • Circular polarized laser induces the formation of nanoparticles. Hybridly polarized beam is a new type of vector beam different from conventional cylindrical vector beam. In our work, we present a simple and effective method to generate hybridly polarized beams by using a cascade of a super structured polarization converter and a quarter-wave plate. The transformation of light field was analyzed by using Jones vector and Jones matrix, and the Stokes parameters of the generated vector beams were measured to verify the states of polarization. Various novel multiscale micro-/nanostructures were fabricated on surfaces of 4H-SiC by using the hybrid vector beams, which are different from that induced by linearly polarized beam or conventional cylindrical vector beam. Experimental results show that the multiscale characteristics can be adjusted with a high degree of freedom by designing states of polarization. This research provides a new idea for preparation of multiscale micro-/nanostructures that may be useful in the fields of nano-/micro-electromechanical systems, thermal photovoltaics, and thermal management. [ABSTRACT FROM AUTHOR]

Micro-engineered glass components play a vital role in various domains, but their full potential remains untapped due to the lack of easily accessible high-precision machining methods for customizable microstructure. Our discovery of a new phenomenon, where laser-modified regions break the rule of inherently isotropic glass etching and regulate a directional anisotropic etching along modified tracks, has led to the development of a laser-guided anisotropic etching (LGAE) method. This method enables crafting precision glass microstructures with sharp features, smooth surfaces, and adjustable shapes and sizes. An ultrafast Bessel beam is utilized to create high aspect-ratio line-shaped modification within the glass. With a higher etching rate than pristine glass, the modified line guides directional anisotropic etching along the modified track, facilitating the formation of a V-shape with an angle altered by the etching ratio. These modified lines can further serve as basic building blocks to interconnect to construct a 3D internal modification region and then guide the glass's overall surface morphology etching evolution, enabling the creation of microstructures featuring designable shapes and adjustable feature sizes. To accurately predict and control the shape of the microstructures, we establish a finite difference etching model that incorporates localized etching rate regulation, validating the robustness and controllability of LGAE. This scalable method has successfully fabricated a 50 μm period micro-pyramid array with high uniformity over a centimeter-scale area, demonstrating its suitability for large-scale manufacturing. The showcased micro-engineered glass components encompass V-groove arrays for fiber alignment, blazed gratings for light modulation, and microchannels with customized trajectories for microfluidic chips. These advancements driven by LGAE can significantly contribute to the progress of glass-based research and industries. [Display omitted] • Line-shaped laser-modified glass exhibits a unique anisotropic wet etching behavior. • Modified line track guides a directional wet etching to create sharp features. • Laser-guided anisotropic etching is developed for precision glass micromachining. • Steady guided etching ensures LGAE's robustness and the shape accuracy. • High-quality microstructures, <10 nm surface roughness, meet optical requirements. [ABSTRACT FROM AUTHOR]

Fabricating precision microgrooves with controllable cross‐sections on difficult‐to‐machine materials is significantly valuable but still challenging. Herein, a patterned laser‐induced microjet‐assisted ablation method for cross‐sectional profiles controllable laser micromachining is proposed. During the liquid‐assisted laser ablation process, debris and bubbles that may disturb the laser energy deposition can be instantaneously expelled by a directional laser‐induced microjet. The Gaussian laser spot is spatially modulated into specific geometric shapes, such as triangles, to tune locally deposited laser energy to carve microgrooves with designed cross‐sections. To achieve customized microgrooves efficiently, a reliable geometrical model based on the ablation threshold theory is developed to guide the processing parameter selection, including the laser spot shape, polarization, pulse energy, and scanning strategies. The simulation and experimental results confirm that this method achieves the decoupled control of the groove depth and width in a single‐path laser ablation process. Using this method, the design and manufacturing of microgrooves with controllable cross‐sections on single crystalline silicon carbide are demonstrated. The patterned laser‐induced microjet‐assisted ablation method provides a new route for fabricating precision microgrooves with controllable cross‐sections on difficult‐to‐machine materials. [ABSTRACT FROM AUTHOR]

The surface modification by ultra-fast laser could regulate the mechanical properties of hard and brittle materials. Since silicon carbide (SiC) is too hard to be machined with acceptable removal rate and quality by mechanical abrasives, and femtosecond laser (fs-laser) assisted grinding could be a potential method to improve the machinability of SiC. Under fs-laser modulating, SiC surface could be modified to generate laser-induced periodic surface structures (LIPSS). Understanding the mechanical properties and material removal mechanism of the LIPPS surface is crucial to accomplish a high efficiency and quality machining process. This paper aims to investigate the effects of fs-laser modification on the mechanical properties, removal mechanism, removal efficiency, and microstructure changes of 4H-SiC surface during removal, together with those of the original 4H-SiC surface for comparison. The hardness and elastic recovery ability of the modified layer are determined by nano-indentation test, and the nano-scratch test is adopted to study the materials removal behavior. The removal efficiency and the quality of the modified surface is significantly improved. Phase transformation is observed in the scratching area, which reveals the existence of ductile mode removal. Moreover, the stress distribution and the change of scratching force on the surface of SiC before and after modification are studied by finite element method (FEM). The results show that the stress distribution and transmission when scratched on the modified surface is lower than that of the original surface, and the scratching force under the same scratch conditions is greatly reduced. With the understanding of materials removal behavior from the whole process of deformation, phase transformation, and separation of LIPPS from substrate, then the fs-laser modification of SiC could be evidenced as an effective method to improve the grinding efficiency and quality in mass production of industry. [ABSTRACT FROM AUTHOR]

The electrospinning electric field is the main factor responsible for the jet stretching force. Previous studies showed that nonhomogeneous electric field would affect the jets formed during the multi-needles electrospinning. Therefore, a multitude of methods were explored to optimize the electric field in multi-needles electrospinning, such as adjusting the supplied voltage on each needle, varying the space of the needles and spatial distribution of the needles. In this paper, three categories of needles distribution were explored for a homogeneous electric field and the design of a higher needles density of electrospinning head. The theoretical and experimental results showed that the homogeneous electric field formed with the trapezoidal head at 15mm distance while the others’ head required over 30mm. Hence, the trapezoidal arrangement is a better multi-needles distribution for electrospinning head, and has much more significance for high yield of electrospinning nanofibers. [ABSTRACT FROM AUTHOR]

Glacier hydrology has profound implications for socio-economic development and nature conservation in arid Central Asia. Process-based hydrological models, which are the traditional tools used to simulate glacier melting, have made considerable contributions to advance our understanding of glacio-hydrology. Simultaneously, deep learning (DL) models have achieved excellent performance in many complex tasks and provide high accuracy. However, it is uncertain whether glacio-hydrological studies can benefit from the application of DL models. In this study, to help us assess water resource change for glacier-influenced regions, we used DL models to simulate glacio-hydrological processes in the Urumqi Glacier No. 1 in northwest China. First, we proposed a newly DL model called Exogenous Regularization Network (ERNet), which focuses on the relationship between exogenous (temperature and precipitation) and endogenous (runoff) variables, balancing the roles of different variables in the simulation process. Second, we compared ERNet with a stacked long short-term memory (LSTM) model and a process-based glacio-hydrology model, FLEX G. Experiments showed that compared with the other two models, ERNet not only performed well in runoff and peak flow simulations but also displayed superior transferability. Third, given that the DL model is data-driven, we experimentally compared the importance of air temperature and precipitation to glacial runoff processes. The results show that air temperature plays a dominant role in glacier runoff generation. We believe that the proposed model provides a useful predictive tool and that the results shed light on the future implication in cold region hydrology. • We proposed a new DL model called the Exogenous Regularization Network (ERNet). • ERNet performed well in runoff and peak flow simulation, and transferability test. • We analysed the importance of meteorological inputs for runoff simulation. • We provided some practical advices for the usage of DL models in glacio-hydrology. [ABSTRACT FROM AUTHOR]