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关键词： GIS   CAD建模   cosRMC建模   pythonOCC   城市场景  

摘要： 基于GIS-CAD-MC集成建模方法,开发了用于快速生成大规模城市建筑蒙特卡罗模型的程序GIS2MC,用于提高城市建筑辐射场计算过程的建模效率。采用通用格式的地理信息系统(Geographic Information System, GIS)数据作为数据输入,使用GeoPandas包解析数据,通过Python内置库以及pythonOCC几何核心,生成城市建筑模块的CAD模型和cosRMC模型。通过选取国内外城市的GIS数据进行验证与测试,结果表明GIS2MC单次运行可生成万个城市建筑轮廓的CAD模型与蒙特卡罗(Monte Carlo,MC)模型,生成MC模型未出现几何模型错误或建筑体积丢失。此外,GIS2MC实现了基于GIS数据的建模区域选择、建筑轮廓预处理以及cosRMC模型材料和内部结构自动配置的辅助功能。

关键词： Distributed CAD system   Simulation efficiency   Simulation framework   Thermal performance  

摘要： This study develops a distributed Computer-Aided Design (CAD) system for scalable thermal performance simulation in clothing engineering, overcoming key limitations of conventional single-server architectures. The proposed framework incorporates three core innovations: (1) a multiphysics coupling engine that models the human–clothing–environment system as a thermal system, integrating Stolwijk’s 25-node human thermoregulation model with dynamic fabric transfer equations via finite-volume discretization; (2) a distributed architecture that improves processing efficiency under multi-user concurrent scenarios; and (3) a five-stage scenario definition workflow supporting parametric modeling of activity-dependent metabolic rates, multi-layer garment configurations (across up to six segments), and environmental boundary conditions. Six simulation cases were tested–running at 8, 10, and 12 km/h under 20°C and 60 % relative humidity for 30 minutes each–demonstrating that the distributed CAD system significantly reduces simulation and user waiting times compared to a legacy Browser/Server system. It also enables visualization of human skin temperature and fabric properties on the trunk during simulated running. This distributed approach facilitates faster, large-scale simulations for designing sportswear and protective clothing, thereby reducing reliance on costly physical prototypes and accelerating the development of more comfortable and functional apparel.

关键词： CAD/CAM restorative materials   Coffee staining   Color stability   Surface roughness   Toothbrushing abrasion  

摘要： This laboratory study aimed to investigate the effects of toothbrushing with different toothpaste formulations on the color stability and surface roughness of CAD/CAM restorative materials following coffee-staining thermocycling. A total of 160 specimens were prepared from four restorative materials: IPS *** CAD, CEREC Tessera, Shofu Block HC, and VITA Enamic (n = 40 each). Following initial measurements, specimens underwent thermocycling in a coffee solution (5000 cycles) to simulate staining. Each group was subsequently divided and brushed with either a whitening toothpaste containing hydrated silica and hydrogen peroxide or a non-whitening toothpaste containing hydrated silica only. A total of 10,000 brushing cycles were performed under standardized conditions. Color stability was assessed using ΔE₀₀ values, and surface roughness was quantified using the Ra parameter at baseline, after thermocycling, and after brushing. Data were analyzed using Kruskal–Wallis and Mann–Whitney U tests with the significance threshold set at p < 0.05. SEM analysis was conducted on one randomly selected specimen per group (x1000). Statistically significant differences in color stability, as assessed by ΔE₀₀ values, were observed among the tested materials (p < 0.001). Resin-based groups, particularly Shofu Block HC, exhibited the greatest reduction in color stability after coffee thermocycling and subsequent brushing (ΔE₀₀ = 1.069, p < 0.001), whereas glass-ceramics (IPS *** CAD and CEREC Tessera) demonstrated superior color stability (ΔE₀₀ ≤ 0.520). Surface roughness increased significantly in resin-containing materials (VITA Enamic ΔRa = 0.036; Shofu Block HC ΔRa = 0.020) compared with glass-ceramics (p < 0.001). No significant differences were detected between whitening and non-whitening toothpastes for either parameter across all groups (p > 0.05). Ra changes were also concluded by SEM. The performance of restorative materials under staining and mechanical agin

关键词： Mesembryanthemum crystallinum   Antioxidants enzymes   Chlorophyll a fluorescence   PEPC   Plant pigments   RuBisCO  

摘要： Facultative CAM plants possess a unique ability to reversibly initiate and suppress β-carboxylation, a metabolic pathway characterised by nocturnal stomatal opening and high water-use efficiency. In the present study, we focused on determining how continuous light modifies the interaction of the Mesembryanthemum crystallinum, a model CAM facultative species, with salinity stress – an ever-growing global-scale plant diversity and productivity threat. Expression of stress-dependent PEPC form and RbcL, chlorophyll a fluorescence, pigment composition and antioxidant enzyme activity were analysed. Expression of both mentioned genes was predictably influenced by salinity stress, with stress-dependent PEPC amount increase accompanied by a concurrent RbcL decline. However, exposing plants already affected by salinity stress to continuous light resulted in a limited RbcL decline – a side-effect exclusively induced by salinity stress. Moreover, a limited expression of salinity-dependent PEPC was concomitantly observed; in M. crystallinum leaves, the content of cryptoxanthin, β-carotene, α-carotene, zeaxanthin, violaxanthin, antheraxanthin and neoxanthin has increased, especially in the case of salinity with continuous light treatments. The total SODs activity was increased in plants exposed to salinity combined with continuous light. This study unravels novel evidence that continuous light treatment may alleviate the detrimental effects of high salinity in facultative CAM plants; these conclusions, however, may potentially be extrapolated to other plant groups, including glycophytes.

摘要： The methods to calculate the winding inductance of electrical devices without a ferromagnetic core have been discussed. The methods for calculating the self- and mutual inductances of windings are suggested based on the analytical calculations of the magnetic field and taking into account the design features of the windings. These suggestions are implemented in the MATLAB environment and can be integrated into electrical CAD systems as an additional calculation module, allowing for the selection of a reasonable calculation method for a specific winding design. The results of testing the developed methods are presented, and the results obtained using each method are compared with those calculated using the field models. The results of this work can be used to develop digital twins of designed devices for preliminary characterization of their key parameters in different operating modes.

关键词： 高光谱成像   机器学习   废旧纺织品   聚酯纤维   氨纶   神经网络  

摘要： 针对复杂废旧纺织品中聚酯纤维和氨纶纤维含量检测精度低、模型易过拟合及泛化能力不足等问题,本文提出了一种基于近红外高光谱成像与优化机器学习算法的快速无损检测方法,用于实现废旧纺织品的自动化识别与分选。采用工作波段为1 000~1 700 nm的推扫式高光谱成像系统采集不同混纺比例样本的光谱数据,并通过黑白板校正、Savitzky-Golay滤波及标准正态变换对数据进行预处理,以降低噪声和散射干扰。针对聚酯纤维含量预测,利用主成分分析提取光谱特征,并构建基于蛇优化算法优化的多层感知机模型(MLP-SO);针对氨纶纤维检测,通过相关性分析筛选敏感波段,结合核主成分分析特征建立随机森林(RF)模型。结果表明,MLP-SO模型在聚酯含量预测中取得决定系数(R2)为0.963、均方根误差(RMSE)为3.546的性能,显著优于传统机器学习模型;RF模型在氨纶含量预测中获得R2为0.901 78、RMSE为1.48,明显优于偏最小二乘回归模型。相关性分析显示1 000~1 100 nm和1 400~1 500 nm为氨纶含量敏感波段,特征可视化结果验证了不同氨纶浓度样本的良好可分性。研究结果表明,高光谱成像结合优化算法可实现复杂废旧纺织品中聚酯与氨纶纤维的快速、无损和定量检测,为纺织品资源回收与绿色循环利用中的高效自动化分选提供了可靠技术支撑。

关键词： 图元识别   计算机视觉   目标检测   计算机辅助设计  

摘要： 图元识别是建筑图纸智能化分析与合规性评审中的关键步骤。尽管DETR(Detection Transformer)框架在通用目标检测领域展现出强大潜力,但其在建筑CAD图元识别这种特定任务中仍面临一些问题。具体而言,DETR在进行CAD图元识别时主要受限于两方面:其一,其特征提取机制对图元尺度变化的适应性不足,难以同时有效表征微小结构细节与大跨度结构信息,导致对小尺度图元漏检或对大尺度图元识别模糊;其二,由于图元有效信息在图像上分布稀疏,其注意力机制难以高效聚焦于关键区域,易受大量无效背景干扰。针对上述问题,本文在DETR框架的基础上进行三方面的改进:采用基于Swin Transformer的多尺度特征提取模块,增强模型对不同尺寸图元的鲁棒表征能力;引入空间稀疏采样注意力机制,优化特征图中有效信息的采样效率,提升关键区域的感知性能;结合对比去噪训练策略,强化模型对稀疏有效特征的定位能力。在实际建筑数据集上的实验表明,本文方法取得了0.675的mAP[0.5-0.95],显著优于现有主流目标检测模型,验证了所提方法在建筑图元识别任务上的有效性与工程实用价值。

关键词： automotive engineering   multidisciplinary   simultaneous design process   unified   modular and agile design process   multidisciplinary design analysis   Collaborative Vehicle Configuration Schema   central data model  

摘要： One of the pressing challenges facing the German automotive sector nowadays is the time-consuming development process of road vehicles, particularly in comparison to other automotive manufacturers. Traditional approaches, i.e., the sequential design process of road vehicles can lead to tedious data exchange and delayed decision-making. The automation of the development process to reduce development time, while taking into consideration the collaboration between the involved multidisciplinary engineering teams and their tools, can be crucial for the German automotive industry to regain its competitive edge. To address this objective, this paper presents an approach that makes use of the Collaborative Vehicle Configuration Schema (CVeCS) and multidisciplinary design analysis and optimization (MDA(O)) techniques. To be more specific, a unified design process is presented that encompasses the conceptual design phase as well as the initial stages of the subsequent detailed development. The potential of this approach to enhance competitiveness of the German automotive sector is demonstrated based on the MDA(O) workflow of the plug-in hybrid electric vehicle named Interurban Vehicle (IUV). The IUV is a research road vehicle designed at the German Aerospace Center. In general, within the context of this paper, the first steps towards automating the entire development process are taken. Overall, this paper concludes that this approach enables a shift from a sequential development process to a simultaneous one providing a unified, modular and agile design process that contributes to enhancing the decision-making process and facilitating interdisciplinary analyses.