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Road traffic accidents occur frequently and have significant impacts on life, property, and society. However, existing researches on road traffic accident risk pay little attention on establishing an effective road network model that accurately describes the transmission characteristics of traffic accident risk. As a result, the accuracy of risk evaluation is limited. To address this issue, we propose a network geographically weighted regression method based on arrival time cost. We conduct experiments using data from roads, traffic violations, traffic accidents, and urban points of interest (POIs) in a city from 2018 to 2020. The experimental results demonstrate that the network geographically weighted regression method, based on arrival time cost, incorporates the propagation nature of traffic accident risk on the road. It significantly reduces evaluation errors and effectively evaluates road traffic accident risk and its influencing factors. The downtown area of the city exhibits high accident risk, primarily concentrated at intersections with heavy traffic flow and certain road points with inadequate transportation facilities. The impact of different types of road traffic violations and urban POIs on the risk of road traffic accidents varies significantly and exhibits strong spatial heterogeneity.(道路交通事故频发，给生命财产造成重大损失，给社会生活带来重大影响。现有针对道路交通事故风险的研究未建立有效的道路网络模型，难以准确描述交通事故风险在道路上的传播特点，评估准确度不高。基于此，提出了一种基于抵达时间成本的网络地理加权回归方法，并利用某县级市2018—2020年的道路、交通违法、交通事故、城市POI等数据开展实验，结果表明，基于抵达时间成本的网络地理加权回归方法融合了交通事故风险在道路上的传播性质，显著降低了评估误差，能够有效评估道路交通事故风险及其影响因素；市中心区域道路交通事故高风险区域主要集中在车流量较大的道路交会处与部分交通设施尚不完备的道路；各类交通违法数量、城市POI对道路交通事故风险的影响程度不同，且具有很强的空间异质性。)

With the advancement of imaging technology, the performance of optical focusing modules becomes crucial for determining imaging quality. Conventional focusing modules frequently face challenges of excessive bulk and weight, complicating the integrated design and limiting application fields. Herein, this study presents a piezo‐actuated optical focusing module (POFM) and the construction strategy to alleviate these issues. A novel radial‐bending resonant‐type piezoelectric actuator (RB‐RPA) is developed to directly drive the POFM. The RB‐RPA, which features a hollow structure (27 × 27 × 7 mm3), utilizes both radial and bending vibration modes of a thin metal plate. It achieves a speed of 122.93 mm s−1, a thrust force of 0.14 N, and a displacement resolution of 0.52 µm. Employing the proposed construction strategy, RB‐RPA is integrated with imaging components to fabricate a POFM prototype. Furthermore, the micrometer‐level displacement resolution of POFM facilitates optical focusing on imaging targets, allowing the acquisition of sharp images within 70 ms. It achieves an image resolution of 119.57 lp mm−1 within a 42 mm segment of the captured image. Finally, a QT‐based interface for the POFM, enables real‐time image capture and sharpness evaluation, thereby enhancing imaging efficiency and integration. This work provides a potential candidate for next‐generation imaging devices. [ABSTRACT FROM AUTHOR]

In this study, we conducted two heat treatment processes, namely double aging (DA) and solid solution followed by double aging (SA), on the Inconel 718 alloy fabricated by selective laser melting (SLM). The aim was to investigate the microstructure evolution and mechanical properties of Inconel 718 under different heat treatment conditions. To achieve this, we employed advanced techniques such as Scanning Electron Microscope (SEM), electron backscattered diffraction (EBSD), energy dispersive spectroscopy (EDS), x-ray diffraction (XRD), Tofwerk time-of-flight secondary ion mass spectrometer (TOF-SIMS), and transmission electron microscopy (TEM). Our experimental findings reveal the presence of cellular high-density dislocation substructures in the as-received (AR) specimens, with a significant accumulation of Laves phase precipitates at grain boundaries and subgrain boundaries. After the DA treatment, the cellular substructure persists, with higher concentrations of γ" and γ' strengthened phases compared to AR specimen. Conversely, the SA specimen undergoes almost complete recrystallization, resulting in the dissolution of brittle Laves phases and a substantial increase in the content of strengthening phase γ" and γ'. As a consequence of the precipitation of the γ" and γ' strengthened phase and the modification of the microstructure, the material exhibits enhanced strength and hardness, albeit at the expense of reduced plasticity. The investigation of the relationship between heat treatment processes and precipitation behavior indicates that the SA heat treatment yields favorable mechanical properties that strike a balance between strength and plasticity. [ABSTRACT FROM AUTHOR]

Multispectral cameras (MSCs) have the capability of detecting and analyzing features invisible to human eyes and are of interest for many applications. However, the traditional MSC suffers from bulkiness since the light filtering and optical focusing mechanisms are independent. Herein, it proposed an integrated strategy that implements two functions through a tunable filtering‐focusing mechanism (TFFM), driven by two degrees of freedom (two‐DOF) piezoelectric tube actuator (PTA). The TFFM can realize light filtering and optical focusing through the rotary and linear motions of PTA. The configuration of PTA is presented, and the working principle is discussed. Then, prototypes of PTA and TFFM are developed, weighing merely 5.5 and 8 g, sizing of Ø7 × 21.4 mm and Ø35 × 7 mm, demonstrating the merits of lightweight and miniaturization. Experiments validate the effectiveness of TFFM, including multispectral images acquired with 0.1 s through rotary motion, focused images obtained with a linear speed of 60.2 mm−1s, and a series of images with different sharpness and wavelengths. The sharpness evaluation algorithms are adopted to determine the sharpest image. The work contributes to reducing the volume of MSC systems with multifunctionalities while keeping the devices simple, providing a practical and effective solution for the integrated design of MSC. [ABSTRACT FROM AUTHOR]

A substrate with microstructure can increase the light extraction efficiency of OLEDs. However, the present preparation methods for micro- and nanostructures are not suited for broad-area manufacturing. In this research, we suggested an electrochemical etching approach to patterning Si substrates and effectively generated a vast area of micro-/nanostructures on the surface of Si. We created OLEDs using this patterned substrate. It was discovered through this study that when the current density is 100 mA/cm2, the brightness increases by 1.67 times and the efficiency increases by 1.43 times, over a planar equivalent. In the future, this electrochemical etching process for patterned silicon substrates might give rise to a new approach to the large-scale manufacture of microstructured silicon substrates. [ABSTRACT FROM AUTHOR]