Simulation Modelling Practice and Theory最新文献_第8页

Bearing compound fault diagnosis considering the fusion fragment data and multi-head attention mechanism considering the actual variable working conditions 考虑融合碎片数据和考虑实际可变工况的多头关注机制的轴承复合故障诊断

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-06-30 DOI: 10.1016/j.simpat.2025.103174

Wujiu Pan , Yuanbin Chen , Xi Li , Junyi Wang , Jianwen Bao

In this paper, a bearing compound fault diagnosis model considering the actual variable working conditions, which combines segment data and multi head attention mechanism, is proposed to improve the accurate recognition ability of compound fault signals. The design of the overall model architecture, which combines the advantages of the convolution layer and the multi-head attention layer, enables the model to better handle fragmented compound fault signals under multiple conditions in engineering practice. In addition, the application strategies under different working conditions are also discussed to ensure that the model has good robustness in the real environment. Through a series of experiments, the excellent diagnostic performance of the proposed model under different working conditions and noise environment is demonstrated. Compared with other existing models, the results showed that the proposed model not only improves the accuracy of fault diagnosis but also demonstrated excellent industrial field adaptability and stability. This research not only provides a new perspective and methodology for the field of fault diagnosis, but also provides a technical basis for industrial intelligence and digital transformation, which has a broad application prospect and value.

为了提高复合故障信号的准确识别能力，提出了一种考虑实际变工况的轴承复合故障诊断模型，该模型将分段数据与多头关注机制相结合。整体模型架构的设计结合了卷积层和多头关注层的优点，使模型在工程实践中能够更好地处理多种条件下的碎片化复合故障信号。此外，还讨论了不同工况下的应用策略，以确保模型在实际环境中具有良好的鲁棒性。通过一系列的实验，证明了该模型在不同工况和噪声环境下的良好诊断性能。结果表明，该模型不仅提高了故障诊断的准确性，而且具有良好的工业现场适应性和稳定性。该研究不仅为故障诊断领域提供了新的视角和方法论，而且为工业智能化和数字化转型提供了技术基础，具有广阔的应用前景和价值。

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引用次数: 0

CCCR: Combining CNP and RTT for congestion control in datacenter networks CCCR：结合CNP和RTT实现数据中心网络的拥塞控制

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-07-28 DOI: 10.1016/j.simpat.2025.103189

Haopeng Li , Dingyu Yan , Yaping Liu , Shuo Zhang

With the rapid development of cloud computing, AI, and big data, data center networks face challenges in achieving ultra-low latency, high bandwidth, and stability. Many data centers still rely on traditional switches, which lack programmable features for advanced congestion control algorithms. In this environment, existing algorithms like DCQCN and TIMELY face two major challenges: (1) a single congestion signal (such as ECN or RTT) struggles to accurately reflect network conditions, leading to delayed congestion detection; (2) heuristic rate control strategies are prone to causing network fluctuations and slow convergence, making it difficult to meet the demands of high-bandwidth links. To address these issues, we propose CCCR, a congestion control algorithm that combines ECN (via CNP) and RTT signals. CCCR enables rapid, accurate rate reduction using receiver-side feedback and employs a adaptive rate increase based on minimum, average, and target RTT. It also adjusts in-flight data using per-flow BDP estimation. Simulations show that compared to DCQCN, TIMELY, and Swift, CCCR reduces the average flow completion time by 11%, 20%, and 12% respectively in incast scenarios, with better fairness than HPCC, and achieves up to 82% reduction in tail flow completion time for medium flows and up to 74% for long flows. In large-scale simulations, CCCR achieves comparable performance to programmable switch-based HPCC algorithms.

随着云计算、人工智能和大数据的快速发展，数据中心网络在实现超低延迟、高带宽和稳定性方面面临着挑战。许多数据中心仍然依赖于传统的交换机，而这种交换机缺乏用于高级拥塞控制算法的可编程功能。在这种环境下，DCQCN和TIMELY等现有算法面临两大挑战：(1)单个拥塞信号（如ECN或RTT）难以准确反映网络状况，导致拥塞检测延迟；(2)启发式速率控制策略容易引起网络波动，收敛速度慢，难以满足高带宽链路的需求。为了解决这些问题，我们提出了CCCR，一种结合ECN（通过CNP）和RTT信号的拥塞控制算法。CCCR使用接收端反馈实现快速、准确的速率降低，并采用基于最小、平均和目标RTT的自适应速率增加。它还使用每流BDP估计来调整飞行中的数据。仿真结果表明，与DCQCN、TIMELY和Swift相比，CCCR在随机场景下的平均流完成时间分别减少了11%、20%和12%，且比HPCC具有更好的公平性，对于中等流尾流完成时间最多减少82%，对于长流尾流完成时间最多减少74%。在大规模仿真中，CCCR达到了与基于可编程开关的HPCC算法相当的性能。

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引用次数: 0

Numerical study of presplit blasting in rock masses with a closed and filled joint using coupled finite-discrete element method 采用有限-离散元耦合方法对封闭充填岩体预裂爆破进行数值研究

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-08-22 DOI: 10.1016/j.simpat.2025.103199

Mansour Sharafisafa , Zeinab Aliabadian , Luming Shen

The optimized performance of rock blasting heavily relies on the presence of discontinuities. These geological features play an important role in wave and fracture propagation in rocks and can be considered a barrier against the blast wave and fracture propagation. Blasting has many applications, but one of the important aspects is presplitting blasting, in which light blasts are operated to create a continuous plane prior to the main blasting. The goal of this particular blast operation is mainly to inhibit damage to the reserved rock. In the presplit blastingin underground rocks, the magnitude of the ground in-situ stresses plays a vital role and dominates the performance of the presplitting, which can lead to an unsuccessful detonation if mismeasured. There is much evidence that, in many cases, the joints are not closed but instead are filled with a different material. Thus, in this study, the performance of presplit blasting in a rock domain with a closed or filled joint is analysed using the combined finite-discrete element method (FDEM) with a gas in fracture logic. First, the applicability of the method is verified against some experiments. Once verified, 2D FDEM models are analysed to evaluate the influence of an inclined closed or filled flaw on blast-induced fracture development. The FDEM results confirm the strong impact of joint inclination angle on the fragmentation degree. Furthermore, it is shown that the performance of the presplit blasting is remarkably dependent on the magnitude of ground in-situ stresses. The results also show that the filling material and its orientation angle with respect to the maximum principal stress have an imposing effect on the success of the presplitting blasting. Also, it is revealed that in the presplit blasting with filled joint, the failure of the filling is a mode failure, while the connecting fractures are of tensile mode.

岩体爆破的优化性能在很大程度上依赖于不连续面的存在。这些地质特征对岩石中的波和裂缝传播起着重要作用，可以被认为是阻止爆炸波和裂缝传播的屏障。爆破有许多应用，其中一个重要的方面是预裂爆破，在主爆破之前进行轻爆以形成一个连续的平面。这种特殊爆破作业的目的主要是抑制对储备岩石的破坏。在地下岩石预裂爆破中，地应力的大小起着至关重要的作用，它决定着预裂爆破的性能，如果测量不当可能导致爆轰不成功。有很多证据表明，在许多情况下，关节并没有闭合，而是被不同的材料填充。因此，在本研究中，采用结合裂隙内气体逻辑的有限-离散单元法（FDEM）对具有闭合或充填节理的岩石域中的预裂爆破性能进行了分析。首先，通过实验验证了该方法的适用性。验证后，分析二维FDEM模型，以评估倾斜闭合或填充缺陷对爆致裂缝发育的影响。FDEM结果证实节理倾角对破碎程度的影响较大。此外，研究表明，预裂爆破的效果与地应力的大小有显著的关系。结果还表明，充填材料及其相对于最大主应力的取向角对预裂爆破的成功与否有重要影响。结果表明，在填缝预裂爆破中，填缝破坏为模态破坏，连接裂缝为拉伸破坏。

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引用次数: 0

Failure mechanisms of block-flexural toppling: An extensive numerical study 块体弯曲倾倒破坏机制：广泛的数值研究

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-08-20 DOI: 10.1016/j.simpat.2025.103198

Mohammad Seyfaddini , Mojtaba Bahaaddini , Saeed Karimi Nasab , Mohammad Hossein Khosravi , Hossein Masoumi

Toppling failure is a common instability in natural rock slopes. The common approaches for investigating toppling failure mechanisms are physical and analytical methods, which encounter special difficulties for the test set-up and limitation in the number of physical experiments as well as complicated governing equations in analytical models. Recent advances in numerical modeling, particularly the discrete element method (DEM), have opened new avenues for understanding the complex mechanisms behind toppling failure. In this work, the ability of numerical method in reproducing toppling mechanism was first investigated through an extensive comparative analysis with physical and analytical methods. Hence, the validated numerical models were employed to statistically examine the individual and interactive effects of different parameters on the block-flexural toppling failure mechanism using the response surface methodology (RSM). To explore the statistical significance of effective parameters, the central composite design (CCD) was employed. The analysis revealed that aspect ratio constitutes the most influential parameter governing block-flexural toppling failure, while block unit weight found to be the least significant factor. Also, it was found out that the block unit weight and the block aspect ratio can cause a decrease in the failure initiation angle. It was concluded that an increase in the joint friction angle and block tensile strength can increase the stability of slope where the joint friction angle can change the shape and location of failure surface. Finally, evaluation of interaction effects showed that the impact of block tensile strength on block-flexural failure increases with an increase in block slenderness.

倾倒破坏是天然岩质边坡中常见的失稳形式。研究倾倒破坏机制的常用方法是物理方法和分析方法，但由于物理实验数量的限制以及分析模型中控制方程的复杂性，这些方法在试验设置上遇到了特殊的困难。数值模拟的最新进展，特别是离散元法（DEM），为理解倾覆破坏背后的复杂机制开辟了新的途径。在这项工作中，通过与物理方法和分析方法的广泛对比分析，首次研究了数值方法在再现倾倒机理方面的能力。在此基础上，采用响应面法（RSM）统计分析了不同参数对块体弯曲倾倒破坏机制的个体效应和交互效应。为探讨有效参数的统计学意义，采用中心组合设计（CCD）。分析表明，长径比是影响块体弯曲倾倒破坏的最重要参数，而块体单元重量是影响最小的因素。同时，还发现砌块单元重量和砌块长径比都能减小破坏起裂角。结果表明，节理摩擦角的增大和块体抗拉强度的增大均能提高边坡的稳定性，其中节理摩擦角会改变破坏面的形状和位置。最后，相互作用效应的评价表明，块体抗拉强度对块体弯曲破坏的影响随着块体长细比的增加而增加。

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引用次数: 0

RCPFH: Reliable controller placement in software-defined networks using fuzzy systems and a modified walrus optimization algorithm RCPFH：在软件定义网络中使用模糊系统和改进的海象优化算法的可靠控制器布局

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-06-17 DOI: 10.1016/j.simpat.2025.103171

Maryam Shamsoddini, Ali Ghaffari, Masoud Kargar, Nahideh Derakhshanfard

Software-Defined Networking (SDN) is a novel network architecture that separates the control plane from the data plane, enabling centralized and programmable management of network resources. One of the key challenges in SDN is determining the optimal number and locations of controllers, called the Controller Placement Problem (CPP), to ensure balanced load distribution, minimal latency, and high network reliability. This paper introduces a novel three-phase approach called Reliable Controller Placement using Fuzzy Logic and Metaheuristic Algorithms (RCPFH), which efficiently optimizes controller placement in SDN environments. In the first phase, the approach employs a fuzzy logic system guided by Levy Flight parameters to estimate the optimal number of controllers by evaluating critical factors such as energy consumption, congestion levels, and load variance across the network. The second phase utilizes a Modified Walrus Optimization Algorithm to identify the most suitable controller positions, considering path reliability, processing capacity, and propagation delay. Finally, in the third phase, backup controllers are selected to enhance system reliability in the event of controller failure. The proposed RCPFH framework is evaluated using four real-world network topologies from the ZOO Topology dataset. Comparative experiments with state-of-the-art approaches demonstrate significant performance improvements: up to a 38 % reduction in energy consumption, an 11 % decrease in load variance, a 36 % increase in network availability, a 17 % reduction in average latency, and a 15 % decrease in link failure rate. These results validate the effectiveness of RCPFH in optimizing SDN performance while maintaining robustness and operational efficiency.

软件定义网络（SDN）是一种新颖的网络架构，它将控制平面和数据平面分离开来，实现对网络资源的集中和可编程管理。SDN的关键挑战之一是确定控制器的最佳数量和位置，称为控制器放置问题（CPP），以确保均衡的负载分配，最小的延迟和高网络可靠性。本文介绍了一种使用模糊逻辑和元启发式算法（RCPFH）的新型三相方法，称为可靠控制器放置，该方法有效地优化了SDN环境中的控制器放置。在第一阶段，该方法采用以Levy Flight参数为指导的模糊逻辑系统，通过评估整个网络的能耗、拥塞水平和负载变化等关键因素来估计控制器的最优数量。第二阶段采用改进的海象优化算法，考虑路径可靠性、处理能力和传播延迟，确定最合适的控制器位置。最后，在第三阶段，选择备用控制器，以提高系统在控制器失效时的可靠性。使用来自ZOO Topology数据集的四种真实网络拓扑来评估所提出的RCPFH框架。与最先进的方法进行的比较实验显示了显著的性能改进：能耗减少38%，负载变化减少11%，网络可用性增加36%，平均延迟减少17%，链路故障率减少15%。这些结果验证了RCPFH在优化SDN性能的同时保持鲁棒性和运行效率的有效性。

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引用次数: 0

Efficient prior specification in procedural 3D modelling 有效的事先规范程序三维建模

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-06-21 DOI: 10.1016/j.simpat.2025.103165

Ioannis Kleitsiotis , George Tsirogiannis , Spiridon Likothanassis

Procedural modelling programs can be used to generate 3D scenes of infinite variety, alleviating the need for manual repetitive tasks in 3D modelling. We utilize a probabilistic programming interpretation of controlled procedural modelling programs, and address the issue of prior misspecification, which can hinder the accurate representation of 3D models. We are interested in cases where prior knowledge is available as probabilistic tail bounds on global, high-level features of the 3D scene. In general, specifying the prior parameters satisfying the aforementioned high-level prior knowledge requires a parameter space search. However, programs with a large number of random variables, 3D scenes described by multiple procedural modelling programs and the need for repeated prior predictive checks might necessitate a prolonged prior parameter search. We reduce the time complexity of prior parameter search, and thus improve the process of modelling 3D scenes, by replacing computationally expensive computations of tail bounds constraints with the lower bounds provided by Selberg’s inequality. We present the theoretical underpinnings of our method and a detailed feasibility problem formulation that can be solved numerically. We compare our method to related approaches in the literature, and finally, we demonstrate its application in the procedural generation of 3D scenes in the agricultural domain.

程序化建模程序可用于生成无限种类的3D场景，减轻了3D建模中手动重复任务的需要。我们利用控制程序建模程序的概率编程解释，并解决了先前错误说明的问题，这可能会阻碍3D模型的准确表示。我们感兴趣的是先验知识作为3D场景全局高级特征的概率尾界可用的情况。一般来说，指定满足上述高级先验知识的先验参数需要进行参数空间搜索。然而，具有大量随机变量的程序，由多个程序建模程序描述的3D场景以及需要重复的先验预测检查可能需要长时间的先验参数搜索。我们降低了先验参数搜索的时间复杂度，从而改进了三维场景建模的过程，方法是用Selberg不等式提供的下界取代计算代价高昂的尾界约束计算。我们提出了我们的方法的理论基础和一个详细的可行性问题的表述，可以解决数值。我们将我们的方法与文献中的相关方法进行了比较，最后，我们展示了它在农业领域3D场景程序生成中的应用。

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引用次数: 0

An advanced 3D continuum finite element model for field-scale in-situ stress simulation of rock media 用于岩石介质现场地应力模拟的先进三维连续体有限元模型

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-07-14 DOI: 10.1016/j.simpat.2025.103183

Atefeh Dargahizarandi , Hossein Masoumi , Abolfazl Hashemi , Biswachetan Saha , Hamid Roshan

Accurate field-scale three-dimensional (3D) stress inversion using numerical simulation is crucial for obtaining in-situ stresses required for the safety and efficiency of underground minerals and energy resources extraction. However, existing commercial packages fall short in dealing with large-scale 3D stress inversion simulations and handling complex geological models containing faults and fractures. This work lays the foundation for the development of an optimised continuum Finite Element (FE) code (3DiStress) to simulate the 3D stress state in elastic media, capable of handling complex geological models. Such a computational framework employs advanced algorithms and state-of-the-art techniques, including the implementation of fault modelling through the effective medium theory, efficient large-scale model handling via vectorisation and sparse matrix storage, Superconvergent Patch Recovery (SPR) to calculate the stresses precisely, and iterative boundary conditions adjustment using Genetic Algorithm (GA) for stress inversion. For large-scale simulations, an effective solver, renowned for its robust handling of large sparse systems (Pardiso), is implemented to solve the resultant system of equations with high efficiency in parallel on a workstation and supercomputers. Furthermore, an iterative boundary condition adjustment is performed using GA, to calibrate the model against on-site stress measurements, thereby optimising the stress distribution. The principal advantages of this computational tool include its capability to accurately simulate complex faulted elastic media, flexible boundary condition optimisation, and the ability to easily adapt and integrate various algorithms, making it an asset for advanced geomechanical engineering applications.

利用数值模拟技术进行准确的场尺度三维应力反演对于获得地下矿产和能源开采安全高效所需的地应力至关重要。然而，现有的商业软件包在处理大规模三维应力反演模拟和处理包含断层和裂缝的复杂地质模型方面存在不足。这项工作为开发优化的连续体有限元（FE）代码（3DiStress）奠定了基础，以模拟弹性介质中的三维应力状态，能够处理复杂的地质模型。这种计算框架采用了先进的算法和技术，包括通过有效介质理论实现断层建模，通过矢量化和稀疏矩阵存储进行高效的大规模模型处理，超收敛补丁恢复（SPR）精确计算应力，以及使用遗传算法（GA）进行应力反演的迭代边界条件调整。对于大规模模拟，实现了一个有效的求解器，以其对大型稀疏系统的鲁棒处理（Pardiso）而闻名，在工作站和超级计算机上并行高效地求解所得方程组。此外，使用遗传算法进行迭代边界条件调整，以根据现场应力测量校准模型，从而优化应力分布。该计算工具的主要优点包括其精确模拟复杂断层弹性介质的能力，灵活的边界条件优化，以及轻松适应和集成各种算法的能力，使其成为先进地质力学工程应用的资产。

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引用次数: 0

Surgical operating theater scheduling: From Discrete-Event Systems point of view 外科手术室调度：从离散事件系统的角度

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-07-28 DOI: 10.1016/j.simpat.2025.103185

Oumaima Boulkhoukh , Ahmed Nait Sidi Moh , Elhoucine Chakir El Alaoui

This paper addresses the decision-making problem of surgical operations scheduling in healthcare systems. The problem involves arranging elective surgeries with assigned intervention dates under the constraint of limited resources such as operating rooms and surgeons. In the present work, we tackle this problem in the point of view of Discrete Event Systems. Our objective is to model and analyze the healthcare systems using two complementary formalisms Timed Colored Petri Nets (TCPN) and (max, ＋) Algebra. To this end, we first develop a TCPN model that represents and studies the behavior of patient care flow. This model allows us to evaluate the performance of the system. Based on the TCPN model, we develop (max, ＋) equations that represent the system behavior using linear mathematical equations. These equations help calculate easily the occurrence dates of surgery activities. Thanks to (max, +) theory we propose a provisional schedule of elective interventions. We show that (max, ＋) powerful lies in its ability to calculate the beginning date and end date of each surgical operation, taking into account limited human and material resources. An illustrative example is presented to demonstrate the effectiveness of the proposed approach.

本文讨论了医疗保健系统中外科手术计划的决策问题。该问题涉及在手术室和外科医生等有限资源的约束下，安排具有指定干预日期的选择性手术。在目前的工作中，我们从离散事件系统的角度来解决这个问题。我们的目标是使用两个互补的形式：定时彩色Petri网（TCPN）和（max, +）代数来建模和分析医疗保健系统。为此，我们首先开发了一个TCPN模型来表示和研究患者护理流程的行为。这个模型使我们能够评估系统的性能。基于TCPN模型，我们开发了使用线性数学方程表示系统行为的（max, +）方程。这些方程有助于计算手术活动的发生日期。由于（max, +）理论，我们提出了一个选择性干预的临时时间表。我们证明（max, +）的强大之处在于它能够计算每次手术的开始日期和结束日期，同时考虑到有限的人力和物力资源。最后通过一个实例验证了该方法的有效性。

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引用次数: 0

Modeling proactive effects of connected autonomous vehicles on urban traffic in adverse weather 在恶劣天气条件下，联网自动驾驶汽车对城市交通的主动影响建模

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-08-07 DOI: 10.1016/j.simpat.2025.103193

Yueting Wang, Zhiqun Hu, Zhaoming Lu, Qinrui An, Xiangming Wen

Adverse weather conditions significantly degrade the environmental perception capabilities of autonomous vehicles (AVs), thereby compromising both traffic safety and operational efficiency. Connected autonomous vehicles (CAVs), leveraging vehicle-to-vehicle (V2V) communication technology, have the potential to mitigate these challenges through cooperative perception mechanisms. Before large-scale deployment of CAVs, it is essential to understand the significant impacts of CAV application on urban traffic characteristics, especially in adverse weather conditions. However, building a realistic simulation for CAV traffic system in adverse weather conditions can be challenging. On the one hand, adverse weather, with chaotic atmosphere behaviors and rapid complex interactions with electromagnetic waves, imposes unpredictable effects on automotive sensors. On the other hand, the dynamic interplay between sensor physics, communication networks, and multi-agent data fusion contributes to uncertainty in CAV driving decisions. To address the challenges, this paper firstly introduces radar theories and builds a physics-based model to realistically simulate weather impacts on sensors at scale. Then, a novel simulation model is proposed for CAV traffic system in rainy conditions, which includes weather-related degraded sensor, unreliable V2V communication, and cooperative perception-based decision making module. Finally, simulations in different levels of rainy conditions are conducted based on a large-scale road network (in the City of Luxembourg) with real traffic data. Results show that CAVs are more effective in improving traffic safety and efficiency under challenging weather conditions. The limits of CAVs in adverse weather are also discussed.

恶劣的天气条件会大大降低自动驾驶汽车的环境感知能力，从而影响交通安全和运营效率。利用车对车（V2V）通信技术的联网自动驾驶汽车（cav）有可能通过合作感知机制缓解这些挑战。在大规模部署自动驾驶汽车之前，有必要了解自动驾驶汽车的应用对城市交通特性的重大影响，特别是在恶劣天气条件下。然而，在恶劣天气条件下建立CAV交通系统的真实模拟可能具有挑战性。一方面，恶劣天气具有混乱的大气行为和与电磁波快速复杂的相互作用，对汽车传感器产生不可预测的影响。另一方面，传感器物理、通信网络和多智能体数据融合之间的动态相互作用增加了自动驾驶汽车驾驶决策的不确定性。为了应对这些挑战，本文首先介绍了雷达理论，并建立了一个基于物理的模型来真实地模拟天气对传感器的影响。在此基础上，提出了一种基于天气相关退化传感器、不可靠V2V通信和基于协同感知的决策模块的雨天CAV交通系统仿真模型。最后，基于大型道路网络（在卢森堡市）和真实交通数据，在不同程度的降雨条件下进行了模拟。结果表明，在恶劣天气条件下，自动驾驶汽车在提高交通安全和效率方面更为有效。本文还讨论了自动驾驶汽车在恶劣天气条件下的局限性。

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引用次数: 0

A graph-based laser path solver algorithm for virtual reality laboratory simulations 一种基于图形的虚拟现实实验室仿真激光路径求解算法

IF 3.5 2区计算机科学 Q2 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Simulation Modelling Practice and Theory

Pub Date : 2025-11-01 Epub Date: 2025-08-09 DOI: 10.1016/j.simpat.2025.103194

Andreas Müller , Stefan Mueller , Tobias Brixner , Sebastian von Mammen

femtoPro is an interactive virtual reality (VR) laser laboratory balancing the contrasting challenges of accuracy and computational efficiency in optics simulations. It can simulate linear and nonlinear optical phenomena in real time, a task that pushes the boundaries of current consumer hardware. This paper details the concept, implementation, and evaluation of a dynamic graph-based solution tailored to the specific requirements and challenges of the simulation. Resource usage is optimized through a selective updating strategy that identifies and preserves laser paths unchanged between simulation frames, eliminating the need for unnecessary recalculations. Benchmarking of real-world scenarios confirms that our approach delivers a smooth user experience, even on mobile VR platforms with limited computing power. The methodologies, solutions and insights outlined in this paper may be applicable to other interactive, dynamic graph-based real-time simulations.

femtoPro是一个交互式虚拟现实（VR）激光实验室，平衡了光学模拟中精度和计算效率的对比挑战。它可以实时模拟线性和非线性光学现象，这一任务突破了当前消费类硬件的极限。本文详细介绍了针对仿真的特定需求和挑战量身定制的基于动态图的解决方案的概念、实现和评估。通过选择性更新策略来优化资源使用，该策略可以识别和保持模拟帧之间的激光路径不变，从而消除不必要的重新计算的需要。现实场景的基准测试证实，我们的方法提供了流畅的用户体验，即使在计算能力有限的移动VR平台上也是如此。本文概述的方法、解决方案和见解可能适用于其他交互式、动态的基于图形的实时仿真。

引用次数: 0