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关键词： 装配式建筑   叠合楼板   现浇混凝土板层   施工技术  

摘要： 近年来,在叠合板现浇钢筋混凝土板层施工中,施工人员也逐渐认识到叠合板现浇板施工技术的重要性。但是,在施工过程中,受各种因素的影响,往往会出现质量问题,影响建筑工程的质量安全。因此,本文首先分析叠合楼板现浇层施工要点,包括预制楼板安装、现浇板层模板支搭、现浇板层位置的校正等,再结合具体案例,验证叠合板现浇钢筋混凝土板层施工的质量可靠性,得出叠合楼板现浇钢筋混凝土板层施工满足相关质量要求,可以为同类工程建设提供参考。

关键词： MATLAB  

摘要： Multi-leaf journal foil bearing (MLJFB) structures are complex, making performance prediction challenging, and the accurate prediction of gas film thickness and pressure distributions is crucial. In this study, comsol finite-element software was used to establish an initial foil assembly and structural deformation simulation model for an MLJFB with bump foils. Using matlab, a compressible gas lubrication model was established and solved using the finite volume method. Real-time data transfer between comsol and matlab enabled a fully coupled fluid-structure interaction simulation. This model meticulously accounts for the pre-tension force in the multi-leaf bearing assembly, contact friction between adjacent foils, and the interaction between the top foil and gas film pressure. The effects of journal movement distance, direction, and top foil overlapping ratio on the bearing capacity as well as the effects of different external load directions on the journal equilibrium position were analyzed based on this model. The results indicate that increasing the top foil overlapping ratio enhances the bearing capacity of the MLJFB. Furthermore, compared to the direction of the top foil overlap position, external loads applied in the direction of the top foil midpoint are more beneficial for bearing operational stability. Copyright © 2024 by ASME.

关键词： 钢框架   消能减震结构   花篮柱   支座设计   焊接工艺  

摘要： 为了解决特殊花篮柱支座在实际施工中面临设计复杂性较高、力学计算模型尚不完善、复杂构件加工难等问题的挑战,本文以济南某智慧产业园基础设施项目花篮柱支座加工为例,通过介绍花篮柱支座的结构设计思路、焊接工艺、制作顺序及焊接参数,提出了分段预拼装的工艺措施。研究结果表明,花篮柱支座在制作过程中采用统一焊接参数(电流240~250 A,电压30~36 V)和分段预拼装工艺,可有效保证复杂构件的制作质量与安装精度,对类似项目具有指导意见。

关键词： 市政道路工程   路基   施工技术   要点  

摘要： 本论文旨在研究市政道路工程中路基施工技术的应用要点,以提高路基的施工质量和整体性能。文章首先分析了路基施工技术的基本要求,包括强度和结构承载力,强调以上硬项要素对道路安全和耐久性的重要性。详细探讨了路基施工的关键技术要点,如施工前的准备工作、基底处理、路基压实施工以及二灰碎石基层施工等,强调每个环节对施工质量的影响。此外,文章重点关注施工过程中的质量控制措施,包括材料质量控制、路基排水施工控制和边坡施工质量控制,以确保路基的稳定性和安全性。通过对以上施工技术要点的深入分析,本文为市政道路工程的高效施工提供有价值的理论参考,旨在提升道路工程的整体建设水平和服务寿命。

关键词： UCNPs   Fe3+   NaYF4   LFPs   MATLAB  

摘要： Traditional methods for latent fingerprint (LFP) detection often suffer from insufficient contrast and background interference, limiting their effectiveness in forensic applications, particularly in complex environments. This study introduces an innovative approach that combines Fe3+-doped NaYF4:Yb, Er upconversion nanoparticles (UCNPs) with digital image processing technology. By optimizing the Fe3+ doping concentration (15 % mmol) and synthesis temperature (220 degrees C), the red emission intensity at 655 nm was enhanced by 13.96 times compared to undoped samples. The amplified red emission originates from energy transfer of |2F7/2, 4T1g > (Yb3+-Fe3+ dimer) to 4F9/2 (Er3+) states, coupled with crystalline field symmetry distortion induced by Fe3+ codoping. Dynamic studies of 4S3/2 and 4F9/2 states under 980 nm pulsed laser excitation, alongside diffuse reflectance analysis, corroborate the proposed upconversion mechanism. Additionally, The optimized UCNPs demonstrated high biocompatibility and stability, achieving LFP visualization with contrast ratios up to 85.03 % and structural similarity scores exceeding 91.58 % via MATLAB-based digital image processing, a significant improvement over conventional methods. This work establishes a robust, non-toxic LFP detection system with potential applications in forensic science.

关键词： MATLAB  

摘要： A revised version of the Matlab implementations of the expansions for the Fermi-Dirac integral and its derivatives is presented. In the new version, our functions for computing the Kummer functions M(a, b, x) and U(a, b, x) are incorporated into the software. The algorithms for computing the Kummer functions are described in [1,2]. In this way, the implementations of the expansions for the Fermi-Dirac integral can be used in earlier Matlab versions and can be easily adapted to GNU Octave. The efficiency of the computations is also greatly improved. New version program summary Program Title: FermiDiracExpans CPC Library link to program files: https://***/10.17632/sk34wtcxhh.2 Licensing provisions: GPLv3 Programming language: Matlab Journal reference of previous version: Comput. Phys. Commun. 283 (2023) 108563 Does the new version supersede the previous version?: Yes Reasons for the new version: With the new version, the implementations of the expansions for the Fermi-Dirac integral can be used in earlier Matlab versions and can be easily adapted to GNU Octave. The efficiency of the computations is also greatly improved. Summary of revisions: The built-in Matlab functions kummerU and hypergeom are replaced by our functions Uabx and Mabx, respectively. These functions improve both the accuracy and efficiency of the built-in Matlab functions for computing the Kummer functions. A few relations satisfied by the Kummer functions are used to adapt the expressions in the expansions involving Kummer functions with negative parameters into expressions with real positive parameters and arguments, as used in our algorithms for Kummer functions. Nature of problem: The evaluation of the relativistic Fermi-Dirac function and its partial derivatives is needed in different problems in applied and theoretical physics, such as stellar astrophysics, plasma physics or electronics. Solution method: Convergent and asymptotic expansions are provided to approximate the relativistic Fermi

关键词： MATLAB  

摘要： Single-molecule localization microscopy (SMLM) achieves nanoscale resolution but remains vulnerable to sample drift, which can compromise data quality. Widely used drift correction methods, based on either fluorescent fiducials or localization events, each have inherent limitations. Here, we present a complete sample stabilization solution combining an imaging system for detecting fiducial markers and NanoDriftGuard, a real-time drift correction software. This open-source software package is available on GitHub (https://***/ZhengyiZ/NanoDriftGuard). This approach can achieve isotropic three-dimensional (3D) stability with a precision of similar to 4 & Aring;. Our MATLAB-based implementation is optimized for rapid execution, allowing real-time drift correction at a rate exceeding 50 Hz. The system requires only a single laser for 3D drift correction and features a compact design that minimizes residual drift to similar to 10 nm/h, ensuring exceptional long-term stability. Finally, we demonstrate the system's performance by imaging nuclear pore complexes using SMLM.

关键词： Boundary element method   Inhomogeneous equations   Thin-bodies   Physics-informed neural networks   Nearly-singular integral  

摘要： The traditional boundary element method (BEM) often faces challenges in efficiently solving inhomogeneous problems, particularly in thin-walled geometries, due to the need for domain discretization and the handling of nearly singular integrals. In this study, we propose an efficient hybrid algorithm that combines the BEM with physics-informed neural networks (PINNs) to solve inhomogeneous potential problems in thin-walled structures. The approach transforms inhomogeneous equations into equivalent homogeneous ones by subtracting a closed-form particular solution, which is derived using the learning capabilities of PINNs. This methodology not only simplifies the problem formulation but also enhances computational efficiency by eliminating the need for domain discretization, making it particularly well-suited for thin-walled geometries. Additionally, the scaled coordinate transformation BEM, a recently developed technique for solving domain integrals, is also employed for comparative analysis. Finally, a nonlinear coordinate transformation is employed to effectively regularize nearly singular integrals, which are critical in BEM for thin structures. The proposed method achieves accurate and reliable results with a small number of boundary elements, even for structures with extremely small thickness-to-length ratios, as low as 10-9. This makes the method highly suitable for modeling thin films and thin-walled structures, particularly in the context of advanced smart materials. The unique contribution of this work lies in the integration of PINNs with BEM to tackle challenges specific to thin-walled inhomogeneous problems, offering a more efficient and accurate solution compared to traditional BEM-based method.

关键词： Geopolymer (GP)   Bamboo fiber   Sustainable   MATLAB   Ansys  

摘要： The current study is integrating bamboo as fibers in clay-based geopolymer (CGP). Bamboo fibers were incorporated 1-3 % with an activator to binder ratio of 0.4 oven-cured at 70,90 and 120 C temperatures. Various molar ratios, ranging from 14 to 18M, were examined to investigate workability, flexural strength, sorptivity, abrasion, and durability tests. The rebound hammer results show compressive strength (CS) of GPC was increased by 10.71% and 9.33 % at 28 and 90 days of testing compared with destructive testing. For durability analysis, geopolymer specimens were subjected to Hydrochloric acid (HCL) with a dilution ratio of 1:*** was observed that there was a mass loss of 27.27 % and a reduction in CS of 20 MPa compared to specimens without HCL. Matlab analysis shows the beam stress distribution maximum deformation at 375 mm, which points to localized stress concentrations followed by a decrease. Ansys analysis of a typical bridge for the size of 200 x 48 and 50 m, the material's ductility and cyclic strength properties demonstrate its ability to deform and endure repeated loading without failure, enhancing the durability and resilience of bridge structures under dynamic conditions. The investigation on bamboo fiber geopolymer concrete contributes to SDGs 9 (Infrastructure), 11 (Sustainable Cities), 13 (Climate Action), and 15 (Life on Land) by promoting robust, eco-friendly, and innovative construction materials.

关键词： Self-organizing maps   Hyperspectral data   Tutorial   MATLAB  

摘要： We present the SOM-RPM Toolbox for MATLAB, which is an interactive command line implementation of the self-organizing map with relational perspective mapping (SOM-RPM) algorithm. SOM-RPM has shown considerable utility for the interpretation of complex hyperspectral data. In essence, it provides a means for interactively exploring similarities between pixels (based on their spectral information) through the so-called similarity map. This manuscript provides an overview of the theoretical underpinnings of SOM-RPM, followed by a detailed description of the SOM-RPM toolbox structure. We supplement these sections with a demonstrative case study using time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging data as the subject of the analysis. This case study emphasizes the interactive nature of the toolbox and the method itself, which allow for exploration of the data based on the SOM-RPM model. It also highlights the analytical potential of the approach. Our primary aim is to make the SOM-RPM method more accessible to the broader scientific community. This manuscript provides sufficient content for a non-expert in machine learning to be able to utilize SOM-RPM for exploratory analysis of their hyperspectral data. The toolbox, and associated documentation, is available through the linked data repository.