Search Results (188)

As a core component of automated logistics systems, delivery robots hold significant application value in the field of unmanned delivery. This research addresses the robot path planning problem, aiming to enhance delivery efficiency and reduce operational costs through systematic improvements to the RIME optimization algorithm. Through in-depth analysis, we identified several major drawbacks in the standard RIME algorithm for path planning: insufficient global exploration capability in the initial stages, a lack of diversity in the hard RIME search mechanism, and oscillatory phenomena in soft RIME step size adjustment. These issues often lead to undesirable phenomena in path planning, such as local optima traps, path redundancy, or unsmooth trajectories. To address these limitations, this study proposes the Multi-Strategy Controlled Rime Algorithm (MSRIME), whose innovation primarily manifests in three aspects: first, it constructs a multi-strategy collaborative optimization framework, utilizing an infinite folding Fuch chaotic map for intelligent population initialization to significantly enhance the diversity of solutions; second, it designs a cooperative mechanism between a controlled elite strategy and an adaptive search strategy that, through a dynamic control factor, autonomously adjusts the strategy activation probability and adaptation rate, expanding the search space while ensuring algorithmic convergence efficiency; and finally, it introduces a cosine annealing strategy to improve the step size adjustment mechanism, reducing parameter sensitivity and effectively preventing path distortions caused by abrupt step size changes. During the algorithm validation phase, comparative tests were conducted between two groups of algorithms, demonstrating their significant advantages in optimization capability, convergence speed, and stability. Further experimental analysis confirmed that the algorithm’s multi-strategy framework effectively suppresses the impact of coordinate and dimensional differences on path quality during iteration, making it more suitable for delivery robot path planning scenarios. Ultimately, path planning experimental results across various Building Coverage Rate (BCR) maps and diverse application scenarios show that MSRIME exhibits superior performance in key indicators such as path length, running time, and smoothness, providing novel technical insights and practical solutions for the interdisciplinary research between intelligent logistics and computer science. Full article

In photoelectrochemical (PEC) biosensing, efficient electron-hole separation is crucial to obtain preferred photocurrent response and analytical performance; thus, constructing developed heterointerfaces with high carrier transfer efficiency is an effective method for sensitive evaluation of analytes. Herein, a 1D ZnIn₂S₄ nanosheet-decorated 2D In₂O₃ tube was developed to integrate with a prostate antigen (PSA)-sensitive aptamer for sensitive PSA antigen detection. 1D In₂O₃ tubes were first prepared by two-step hydrothermal and annealing methods, followed by the in-situ growth of ZnIn₂S₄ nanosheets. Morphology, optical properties, structure, and PEC performance of prepared In₂O₃-ZnIn₂S₄ were characterized by scanning electron microscopy, transmission electron microscopy, ultraviolet–visible spectrophotometry, X-ray diffraction, X-ray photoelectron spectroscopy, and an electrochemical workstation. Benefiting from the photoelectric effect and specific 1D/2D hierarchical structure, In₂O₃-ZnIn₂S₄ displayed enhanced optical absorption and photocarrier separation, thus a superior photoelectrochemical response. Proposed bioassay protocol possessed a linear range from 0.001 to 50 ng/mL and a detection limit at 0.00037 ng/mL. In addition, this biosensor exhibited satisfactory anti-interface ability and stability, which also could be extended to other quantitative platforms for detecting other proteins. Full article

Using reduced-dimensional halide perovskites is emerging as a promising strategy for enhancing the stability of optoelectronic devices such as solar cells, even if their performances remain a step below those of the 3D halide perovskites. Two-dimensional Ruddlesden–Popper (2D-RP) structures are characterized by the n parameter that represents the number of PbI₆ layers in the spacer-separated perovskite slabs. The present study focuses on formamidinium (FA)-based 2D-RP type perovskites denoted as PMA₂FA_n−1Pb_nI_3n+1 (PMA = Phenylmethylammonium or benzylammonium). We investigate the effect of n on the one step growth mechanism and the film morphology, microstructure, phase purity, and optoelectronic properties. Our findings demonstrate that the average n is not only determined by the initial spacer content in the precursor solution but also by the thermal annealing process that leads to a partial spacer loss. Depending on n, perovskite solar cells achieving a power conversion efficiency up to 21%, coupled with enhanced film stability compared to 3D perovskites have been prepared. By using MACl additive and an excess of PbI₂ in the perovskite precursor solution, we have been able to achieve high efficiency and to stabilize the n = 5 perovskite solar cells. This research represents a significant stride in comprehending the formation of FA-based layered perovskites through one-step sequential deposition, enabling control over their phase distribution, composition, and orientation. Full article

Hot stamping is a promising method to manufacture ultra-high-strength automotive steel components with high dimension accuracy. In this work, two actual industrial production flows (with and without Al-Si hot dipping) were investigated to reveal their microstructural evolution and hydrogen content at different production steps. Meanwhile, the variations in composition and phase structures of the Al-Si coating layer were studied in terms of energy-dispersive spectrometry and electron backscattering diffraction techniques. The results showed that the microstructure at the steel substrate changed from the pancake-shaped pearlite and ferrite, degenerated pearlite and annealed ferrite, lath martensite, and then tempered martensite with the progress of the production steps, which was not affected by the Al-Si hot dipping. The final coating layer exhibited a multi-sublayer structure with the alternative distribution of FeAl and Fe₂Al₅, which contained many microcracks on the brittle phase Fe₂Al₅. The Al-Si-coated specimens always had higher hydrogen content than the bare steel specimens because of the hydrogen generation at the hot stamping stage and hydrogen absorption during the hot-dip aluminizing stage. Full article

Radial basis function (RBF) networks are an established parametric machine learning tool which has been extensively utilized in data classification and data fitting problems. These specific machine learning tools have been applied in various scientific areas, such as problems in physics, chemistry, and medicine, with excellent results. A two-step technique is usually used to adjust the parameters of these models, which is in most cases extremely effective. However, it does not effectively explore the value space of the network parameters and often results in parameter stability problems. In this paper, the use of a bounding technique that explores the value space of the parameters of these networks using intervals generated by a procedure based on the Simulated Annealing method is recommended. After finding a promising range of values for the network parameters, a genetic algorithm is applied within this range of values to more effectively adjust its parameters. The new method was applied on a wide range of classification and regression datasets from the relevant literature and the results are reported in the current manuscript. Full article

A simple two-step approach was proposed to obtain hBN thin films with high crystalline quality, meaning that the films were initially prepared by using an RF magnetron sputtering technique and subsequently followed by a post-annealing process at a high temperature. In the case of introducing Al₂O₃ nanoparticles, the effects of annealing temperature from 1000 °C to 1300 °C and annealing time from 0.5 h to 1.5 h on the recrystallization process of the grown hBN films were systematically studied by using XRD and SEM technologies. The introduction of Al₂O₃ impurities during the annealing process successfully reduced the transition temperature of hexagonal phase BN by more than 300 °C. The crystalline quality of hBN films grown by RF magnetron sputtering could be effectively enhanced under annealing at 1100 °C for 1 h. The DUV detectors were prepared using the hBN films before and after annealing, and showed a notable improvement in detector performance by using annealed films. It has significant application value in further enhancing the performance of DUV photodetectors based on high-quality hBN films. Full article

A two-step annealing treatment was applied on a fully transparent amorphous InGaZnO4 (a-IGZO) top-gate thin-film transistor (TG-TFT) to improve the device performance. The electrical properties and stabilities of a-IGZO TG TFTs were significantly improved as the first-annealing temperature increased from 150 °C to 350 °C with a 300 °C second-annealing treatment. The a-IGZO TG-TFT with the 300 °C first-annealing treatment demonstrated the overall best performance, which has a mobility of 13.05 cm²/(V·s), a threshold voltage (V_th) of 0.33 V, a subthreshold swing of 130 mV/dec, and a I_on/I_off of 1.73 × 10⁸. The V_th deviation (ΔV_th) was −0.032 V and −0.044 V, respectively, after a 7200 s positive and negative bias stress under the gate bias voltage V_G = ±3 V and V_D = 0.1 V. The Photoluminescence spectra results revealed that the distribution and the density of defects in a-IGZO films were changed after the first-annealing treatment, whereas the X-ray photoelectron spectroscopy results displayed that contents of the oxygen vacancy and Ga-O bond varied in annealed a-IGZO films. In addition, a-IGZO TG-TFTs had achieved a transmittance of over 90%. Research on the effects of the first-annealing treatment will contribute to the fabrication of highly stable top-gate TFTs in the fields of transparent flexible electronics. Full article

Probabilistic models in physics often require the evaluation of normalized Boltzmann factors, which in turn implies the computation of the partition function Z. Obtaining the exact value of Z, though, becomes a forbiddingly expensive task as the system size increases. A possible way to tackle this problem is to use the Annealed Importance Sampling (AIS) algorithm, which provides a tool to stochastically estimate the partition function of the system. The nature of AIS allows for an efficient and parallel implementation in Restricted Boltzmann Machines (RBMs). In this work, we evaluate the partition function of magnetic spin and spin-like systems mapped into RBMs using AIS. So far, the standard application of the AIS algorithm starts from the uniform probability distribution and uses a large number of Monte Carlo steps to obtain reliable estimations of Z following an annealing process. We show that both the quality of the estimation and the cost of the computation can be significantly improved by using a properly selected mean-field starting probability distribution. We perform a systematic analysis of AIS in both small- and large-sized problems, and compare the results to exact values in problems where these are known. As a result, we propose two successful strategies that work well in all the problems analyzed. We conclude that these are good starting points to estimate the partition function with AIS with a relatively low computational cost. The procedures presented are not linked to any learning process, and therefore do not require a priori knowledge of a training dataset. Full article

Non-noble metal electrocatalysts for the hydrogen oxidation reaction (HOR) that are both highly active and low-cost are essential for the widespread use of fuel cells. Herein, a simple two-step method for creating an in-plane heterostructure of Ni₃N/MoSe₂ loaded on N-doped reduced graphene oxide (Ni₃N/MoSe₂@N-rGO) as an effective electrocatalyst for the HOR is described. The process involves hydrothermal treatment of the Ni and Mo precursors with N-doped reduced graphene oxide, followed by the annealing with urea. The Ni₃N/MoSe₂@N-rGO catalyst exhibits high activities for the HOR, with current densities of 2.15 and 3.06 mA cm⁻² at 0.5 V vs. the reversible hydrogen electrode (RHE) in H₂-saturated 0.1 M KOH and 0.1 M HClO₄ electrolytes, respectively, which is comparable to a commercial 20% Pt/C catalyst under similar experimental conditions. Furthermore, the catalyst demonstrates excellent durability, maintaining its performance during accelerated degradation tests for 5000 cycles. This work offers a practical framework for the designing and preparing of non-precious metal electrocatalysts for the HOR in fuel cells. Full article

In this study, seeded zinc oxide (Z-ZnO) thin films were fabricated by a two-step electrochemical deposition process. Different annealing temperatures (300, 400, 500, and 600 °C) were investigated to determine the most effective temperature for the photocatalytic activity. Comprehensive analyses were conducted using X-Ray Diffraction (XRD), scanning electron microscopy (SEM), and UV–visible spectrophotometry. The XRD results confirmed the formation of a wurtzite hexagonal structure, with the highest crystallinity observed at 400 °C. The lowest band gap value, 3.29 eV, was also recorded for Z-ZnO thin film annealed at 400 °C. SEM images revealed that the thin film treated at 400 °C exhibited a well-defined and uniform structure, contributing to its enhanced properties. The photocatalytic efficiency of ZnO (without seeding layer) and Z-ZnO thin films annealed at 400 °C was evaluated through the degradation of tetracycline hydrochloride (TCH) to prove the effect of the presence of a primary seeding layer on ZnO 400 °C thin film efficiency. The degradation efficiency of ZnO thin film without seeding layer was 69.8%. By applying a seeding layer in Z-ZnO 400 °C thin film, the degradation efficiency has been increased to 75.8%. On the other hand, Z-ZnO 400 °C thin film achieved a high degradation efficiency of 82.6% over 300 min in the photoelectrocatalytic system. The obtained Z-ZnO thin films annealed at 400 °C are highly effective photocatalysts and photoelectrocatalysts, offering a significant potential for the degradation of pharmaceuticals and other pollutants in water. Full article

Optimization is a crucial challenge across various domains, including finance, resource allocation, and mobility. Quantum computing has the potential to redefine the way we handle complex problems by reducing computational complexity and enhancing solution quality. Optimization, particularly of objective functions, stands to benefit significantly from quantum solvers, which leverage principles of quantum mechanics like superposition, entanglement, and tunneling. The Ising and Quadratic Unconstrained Binary Optimization (QUBO) models are the most suitable formulations for these solvers, involving binary variables and constraints treated as penalties within the overall objective function. To harness quantum approaches for optimization, two primary strategies are employed: exploiting quantum annealers—special-purpose optimization devices—and designing algorithms based on quantum circuits. This review provides a comprehensive overview of quantum optimization methods, examining their advantages, challenges, and limitations. It demonstrates their application to real-world scenarios and outlines the steps to convert generic optimization problems into quantum-compliant models. Lastly, it discusses available tools and frameworks that facilitate the exploration of quantum solutions for optimization tasks. Full article

Platinum (Pt)-based heterogeneous catalysts show excellent performance for the electrocatalytic hydrogen evolution reaction (HER); however, the high cost and earth paucity of Pt means that efforts are being directed to reducing Pt usage, whilst maximizing catalytic efficiency. In this work, a two-step laser annealing process was employed to synthesize Pt single-atom catalysts (SACs) on a MOF-derived carbon substrate. The laser irradiation of a metal–organic framework (MOF) film (ZIF67@ZIF8 composite) by rapid scanning of a ns pulsed infrared (IR; 1064 nm) laser across the freeze-dried MOF resulted in a metal-loaded graphitized film. This was followed by loading this film with chloroplatinic acid (H₂PtCl₆), followed by further irradiation with an ultraviolet (UV; 355 nm) laser, resulting in pyrolysis of H₂PtCl₆ to form the SAC, along with a further reduction of the MOF to form a Pt-decorated laser-induced annealed MOF (Pt-LIA-ZIF8@ZIF67). The Pt-LIA-ZIF8@ZIF67 catalyst with a Pt loading of 0.86 wt. % exhibited exceptionally high activity for the HER in acidic conditions. The atomically dispersed Pt on the carbon substrate exhibited a small overpotential of 68.8 mV at 10 mA cm⁻² for the hydrogen evolution reaction with a mass activity 20.52 times that of a commercial Pt/C catalyst at an overpotential of 50 mV vs. RHE. Finally, we note that the synthesis method is simple, fast, and versatile, and potentially scalable for the mass production of SACs for electrocatalytic applications. Full article

Porcine reproductive and respiratory syndrome virus (PRRSV) is the pathogen that causes porcine reproductive and respiratory syndrome (PRRS), leading to abortion of sows and the manifestation of respiratory diseases in piglets. PRRSV strains are categorized into two distinct genotypes: PRRSV–1 and PRRSV–2. PRRSV–2 can be further classified into several lineages, including sub–lineage 1.8 (NADC30–like), sub–lineage 1.5 (NADC34–like), lineage 8 (HP–PRRSV–like), lineage 5 (VR–2332–like), and lineage 3 (QYYZ–like), all of which are prevalent in China. In order to identify PRRSV–1 and PRRSV–2, two primer–probe combinations were designed, targeting the M gene. In order to further differentiate the five lineages of PRRSV–2, another five primer–probe combinations were designed, targeting the Nsp2 gene. A TaqMan–based multiplex RT–qPCR assay was subsequently developed, integrating the aforementioned seven sets into two primer pools. Following the optimization of primer concentration and annealing temperature, a comprehensive evaluation was conducted to assess the assay’s amplification efficiency, specificity, repeatability, and sensitivity. The developed multiplex RT–qPCR method exhibited excellent repeatability, with coefficients of variation (CVs) less than 2.12%. The detection limits for all seven targets were found to be less than 5 copies/μL. Ultimately, the method was utilized for the detection of a total of 1009 clinical samples, with a PRRSV–positive rate of 7.63% (77/1009). Specifically, the reference method was utilized to further confirm the status of the 77 PRRSV–positive samples and another 27 samples suspected of PRRSV infection. The sensitivity of the method was 97.40% (75/77), and the specificity was 96.30% (26/27), resulting in an overall coincidence rate of 97.12% (101/104). All the PRRSV–positive samples were typed as NADC30–like strains, and the accuracy of this typing was further confirmed by Sanger sequencing. In conclusion, A one–step multiplex RT–qPCR method was successfully constructed, evaluated, and applied to detect clinical samples. The assay provides an easy–to–operate, time–saving, and highly efficient way for the quick identification of PRRSV and simultaneous detection of five PRRSV–2 lineages prevalent in China. The method could offer guidance for PRRSV prevention and control measures. Full article

In Caribbean islands, the washing ashore of tons of pelagic Sargassum spp., consisting of two species Sargassum fluitans and Sargassum natans, has been regularly occurring since 2011. As green lubrication is a growing trend in the tribology industry, biochar is a promising alternative. Sargassum biochars, produced from Sargassum pelagic algae, are therefore being studied as solid lubricants. This study aims to explore their potential applications. Biochars from brown algae were pyrolyzed at 400 °C and then annealed at different temperatures (from 600 °C to 1500 °C). The Raman spectra collected on the different biochars showed that there was a structural organization of the biochars as the temperature increased. The tribologic properties of the biochars were studied and compared to a solid lubricant reference (exfoliated graphite). Raman spectroscopy analysis revealed a progressive structural reorganization with increasing temperature, leading to a 58% reduction in the coefficient of friction. The morphology and the structure of the tribofilm are investigated by profilometry, scanning electron microscopy, and Raman microspectrometry. Overall, these results can be considered as a first step for utilizing the biochar derived from brown algae Sargassum sp. as an additive in the lubricant industry, for the purpose of emission reduction. Full article

Ion implantation in diamond crystals is widely used both for producing conducting microstructures in the bulk of the material and for creating isolated photon emitters in quantum optics, photonics, cryptography, and biosensorics. The photoluminescence (PL) spectra of helium ion-implanted diamonds are dominated by two sharp emission lines, HR1 and HR2 (from Helium-Related), at ~536 and 560 nm. Here, we report on PL studies of helium-related optical centers in diamonds. Experiments have been carried out on a (110) plate of natural single-crystal type IIa diamonds. The uniform distribution of radiation defects in a 700 nm-thick layer was obtained by ten cycles of multiple-energy (from 24 to 350 kV) helium ion implantation with a total dose of 5 × 10¹⁶ cm⁻². The diamonds were annealed in steps in a vacuum oven at temperatures from 200 to 1040 °C. It is demonstrated that helium ion implantation in diamonds followed by annealing gives rise to more than a dozen various centers that are observed in the PL spectra in the range of 530–630 nm. The transformations of the PL spectra due to annealing are investigated in detail. The spectral shapes of phonon sidebands are determined for the HR1, HR2, and HR3 bands with ZPLs at ~536, 560, and 577 nm, respectively, and it is shown that these bands are attributed to interstitial-related centers in diamonds. The reported results are important for understanding the structure and properties of helium-related defects in diamonds. Full article