Simulation Modelling Practice and Theory最新文献_第10页

Evaluating traffic and safety impacts of diverging diamond interchange replacing roundabouts: A microsimulation study 分道菱形立交取代环形交叉路口对交通和安全影响的微观模拟研究

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: 2025-07-17 DOI: 10.1016/j.simpat.2025.103179

Jingshuo Qiu , Léah Camarcat , Paraskevi Koliou , Yuxiang Feng , Nicolette Formosa , Georgios Zacharopoulos , Paraskevi Michalaki , Panagiotis Angeloudis , Mohammed Quddus

With increasing traffic volumes and worsening congestion, conventional interchanges are facing ever-growing challenges. These issues can potentially be mitigated by implementing suitable alternative designs, such as the Diverging Diamond Interchange (DDI). While simulation studies and real-world implementations have validated the DDI’s superiority over conventional interchanges, existing research primarily focuses on right-hand driving and has not considered roundabout layouts prevalent in the UK. This study employs the simulation of the UK Strategic Road Network (SRN) to address this gap. Four hypothetical scenarios are constructed, transitioning conventional junctions between J23 and J26 on the M1 Motorway of SRN to DDIs. By comparing a series of Key Performance Indicators (KPIs), the study quantitatively assesses the impact of DDI implementation on traffic flow, delay and safety. The simulation results reveal that replacing roundabouts to DDIs in a motorway corridor can lead to a 55% reduction in average delay and a 5.96% increase in average speed. However, upon evaluating traffic safety through the Surrogate Safety Assessment Model, a slight decline in the majority of safety performance measures is observed. This study provides evidence to support the adoption of DDIs in the UK, highlighting the trade-offs between improved traffic flow and potential safety concerns.

随着交通流量的增加和拥堵的加剧，传统的立交面临着越来越大的挑战。这些问题可以通过实施合适的替代设计来缓解，例如分流钻石交换（DDI）。虽然仿真研究和实际应用已经验证了DDI相对于传统立交的优越性，但现有的研究主要集中在右侧驾驶，并没有考虑到英国普遍存在的环形交叉路口布局。本研究采用英国战略道路网络（SRN）的模拟来解决这一差距。构建了四种假设情景，将SRN M1高速公路J23和J26之间的传统路口转换为ddi。本研究通过比较一系列关键绩效指标（kpi），定量评估实施DDI对交通流、延误和安全的影响。仿真结果表明，在高速公路走廊内，将环形交叉路改为ddi，平均延误减少55%，平均速度提高5.96%。然而，在通过替代安全评估模型评估交通安全时，观察到大多数安全绩效指标略有下降。这项研究为支持英国采用ddi提供了证据，强调了改善交通流量和潜在安全问题之间的权衡。

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引用次数: 0

Analysis and optimizations of PMI and rank selection algorithms for 5G NR 5G NR的PMI和rank选择算法分析与优化

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: 2025-06-19 DOI: 10.1016/j.simpat.2025.103162

Gabriel Carvalho, Sandra Lagén

Multiple-Input Multiple-Output (MIMO) is crucial for enhancing spectral efficiency, channel capacity, coverage, and robustness. However, it requires significant computations to determine a precoding matrix for transmitted data streams. In closed-loop MIMO, as adopted in 3GPP 5G NR, these computations occur on the user side. To avoid transmitting large matrices, 3GPP defined codebooks with pre-defined precoding matrices indexed by the Precoding Matrix Indicator (PMI). The User Equipment (UE) selects a PMI and a Rank Indicator (RI) to report to the Next Generation Node Base (gNB) as part of the Channel State Information (CSI) feedback. PMI/RI selection can be done via exhaustive search or more efficient techniques, which are crucial for real UE implementations due to their impact on computational complexity and energy consumption. This paper analyzes various PMI/RI selection techniques using the open-source ns-3 5G-LENA simulator. We have implemented state-of-the-art techniques in the system-level simulator and carried out extensive simulation campaigns. Also, we propose new PMI/RI selection methods by focusing on performance versus computational complexity trade-offs. Our proposed techniques show a superior simulation speedup (3.71x to 1.119x) with minimal throughput degradation (3% to 3.3%) compared to exhaustive search, depending on sub-band downsampling settings. Other state-of-the-art techniques implemented exhibit greater throughput losses (up to 8.3%) for a lower speedup (up to 3.54x) or similar losses with smaller speedups and potential slowdowns.

多输入多输出（MIMO）对于提高频谱效率、信道容量、覆盖范围和鲁棒性至关重要。然而，它需要大量的计算来确定传输数据流的预编码矩阵。在3GPP 5G NR采用的闭环MIMO中，这些计算发生在用户端。为了避免传输大矩阵，3GPP定义了带有预定义的预编码矩阵的码本，这些预编码矩阵由预编码矩阵指示器（PMI）索引。用户设备（UE）选择一个PMI和一个Rank Indicator （RI）作为通道状态信息（CSI）反馈的一部分报告给下一代节点基础（gNB）。PMI/RI选择可以通过穷举搜索或更有效的技术来完成，由于它们对计算复杂性和能耗的影响，这对于真正的UE实现至关重要。本文使用开源的ns-3 5G-LENA模拟器分析了各种PMI/RI选择技术。我们在系统级模拟器中实施了最先进的技术，并进行了广泛的模拟活动。此外，我们通过关注性能与计算复杂性的权衡，提出了新的PMI/RI选择方法。与穷举搜索相比，我们提出的技术显示出卓越的模拟加速（3.71倍至1.119倍），吞吐量下降最小（3%至3.3%），具体取决于子带下采样设置。实现的其他最先进的技术在较低的加速（高达3.54倍）下表现出更大的吞吐量损失（高达8.3%），或者在较小的加速和潜在的减速下表现出类似的损失。

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引用次数: 0

Peridynamic modeling of rock cutting under a TBM disc cutter using LS-DYNA 基于LS-DYNA的TBM盘式切割机岩石切削动力学模拟

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

Simulation Modelling Practice and Theory

Pub Date : 2025-09-01 Epub Date: 2025-05-20 DOI: 10.1016/j.simpat.2025.103146

Rashid Hajivand Dastgerdi , Mohammad Salimi , Torsten Wichtmann , Agnieszka Malinowska

Rock cutting force prediction and damage assessment are crucial elements in optimizing tunneling and excavation equipment performance. This study presents a numerical investigation of rock-tool interaction using a Linear Cutting Machine (LCM) test on Colorado Red Granite, implemented through the bond-based Peridynamic framework in LS-DYNA. The numerical model evaluates both normal and rolling forces at three distinct penetration depths (3.2 mm, 5.1 mm, and 6.4 mm). Results demonstrate exceptional correlation with experimental data, achieving accuracy within 0.5–4 % for normal forces and 8–14 % for rolling forces. Furthermore, the model successfully captures the morphology and extent of the induced damage zone during the cutting process. The computational efficiency is particularly noteworthy, with a runtime of only 1 hour and 33 min on a standard engineering workstation. This study establishes the bond-based Peridynamic approach in LS-DYNA as a robust and practical methodology for simulating rock-tool interactions, providing valuable insights for the optimization of cutting tool design in rock excavation applications.

岩石切削力预测和损伤评估是优化隧道开挖设备性能的关键环节。本研究通过LS-DYNA中基于键的periddynamics框架，对Colorado红色花岗岩进行了线性切割机（LCM）试验，对岩石-工具相互作用进行了数值研究。数值模型评估了三种不同穿透深度（3.2 mm、5.1 mm和6.4 mm）下的法向力和轧制力。结果证明了与实验数据的异常相关性，法向力和轧制力的精度分别在0.5 - 4%和8 - 14%之间。此外，该模型成功地捕获了切削过程中诱导损伤区的形态和范围。计算效率特别值得注意，在标准工程工作站上运行时间仅为1小时33分钟。本研究在LS-DYNA中建立了基于键合的周动力学方法，作为模拟岩石-工具相互作用的稳健实用方法，为岩石开挖应用中刀具设计的优化提供了有价值的见解。

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引用次数: 0

Modeling and simulation of L-shaped merging behavior incorporating behavioral characteristic lines 结合行为特征线的l型合并行为建模与仿真

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

Simulation Modelling Practice and Theory

Pub Date : 2025-09-01 Epub Date: 2025-05-30 DOI: 10.1016/j.simpat.2025.103150

Wenhang Li , Yi Li , Ping Yu , Jianhua Gong , Haonan Ma

Merging behavior is a common phenomenon in real-life environments that may lead to congestion and even stampedes. In this study, we examined merging behavior in l-shaped corridors and identified phenomena such as behavioral characteristic lines and turning urgency. These findings were incorporated to develop a model for l-shaped merging behavior. Comparisons between real and simulated behaviors show that the model successfully replicates both the spatial and temporal characteristics of the turning and merging processes, validating its applicability. Further analysis of various pedestrian and spatial factors affecting l-shaped merging behavior and traffic efficiency via the model reveals that (1) moderate yielding by pedestrians in the main corridor increases traffic efficiency, while no yielding or excessive yielding reduces efficiency; (2) increasing the desired velocity increases efficiency; however, the benefits diminish beyond velocities of 2.0 m/s; (3) interpersonal distances in both corridors influence the overall traffic efficiency, and maintaining pedestrian spacing at or below 2.0 m is recommended; and (4) larger turning areas increase merging efficiency, indicating that small-scale optimization of key local spaces can significantly increase efficiency. These insights are valuable for managing pedestrian behavior and designing l-shaped corridors.

合并行为是现实生活中常见的现象，可能导致拥堵甚至踩踏。在本研究中，我们研究了l形走廊的合并行为，并发现了行为特征线和转弯紧迫性等现象。这些发现被纳入到l型合并行为的模型中。仿真结果表明，该模型成功地复制了转弯和合并过程的时空特征，验证了该模型的适用性。通过该模型进一步分析了影响l型归并行为和交通效率的各种行人因素和空间因素，结果表明：(1)主干道行人适度让让提高了交通效率，行人不让让或过度让让降低了交通效率；(2)期望速度越大，效率越高；然而，当速度超过2.0 m/s时，这种优势就会减弱；(3)两个廊道的人际距离影响整体交通效率，建议保持行人间距在2.0 m以下；(4)转弯面积越大，合并效率越高，说明局部关键空间的小规模优化可以显著提高合并效率。这些见解对于管理行人行为和设计l形走廊很有价值。

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引用次数: 0

An Intelligent Pedestrian Model with perception distance and speed to better reproduce traffic dynamics in the single-file movement 具有感知距离和速度的智能行人模型，以更好地再现单队列运动中的交通动态

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

Simulation Modelling Practice and Theory

Pub Date : 2025-09-01 Epub Date: 2025-05-22 DOI: 10.1016/j.simpat.2025.103145

Ning Guo , Changqing Zhang , Xiang Ling , Jiajia Chen , Chaoyun Wu , Qingyi Hao , Kongjin Zhu

In the pedestrian traffic flow, individuals should continuously adjust the movement speed and direction based on the distance to and speed of the surrounding ones. However, during the interaction process, the pedestrian can hardly obtain the real distance and speed instantly, and he/she has to instead rely on perceptual estimates. Current pedestrian flow models typically overlook this crucial relationship between the real and perceived variables. In this paper, we propose an Intelligent Pedestrian model (IPM) incorporating perception headway and speed in the single-file movement scenarios. Experiments to estimate distance and speed are conducted respectively to establish quantitative functions for perception. Individuals tend to overestimate these two variables on average, with perception deviations exhibiting significant variability. Furthermore, it can effectively capture the headway fluctuation characteristics in the stop-and-go flow. Sensitivity analysis reveals that systematic overestimation or underestimation influences the average speed in the flow, while perception heterogeneity predominantly affects the headway fluctuation patterns.

在行人交通流中，个体应根据与周围人群的距离和速度，不断调整移动速度和方向。然而，在交互过程中，行人很难即时获得真实的距离和速度，只能依靠感知估计。目前的行人流量模型通常忽略了真实变量和感知变量之间的重要关系。在本文中，我们提出了一种包含感知车头时距和速度的智能行人模型（IPM）。分别对距离和速度进行估计实验，建立感知的定量函数。平均而言，个体倾向于高估这两个变量，感知偏差表现出显著的可变性。此外，该方法还能有效捕捉车辆走走停停时的车头时距波动特征。敏感性分析表明，系统的估计过高或过低会影响平均速度，而感知异质性主要影响车头时距波动模式。

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引用次数: 0

A credibility evaluation method for digital twin based on improved evidence theory 基于改进证据理论的数字孪生可信度评估方法

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

Simulation Modelling Practice and Theory

Pub Date : 2025-09-01 Epub Date: 2025-05-26 DOI: 10.1016/j.simpat.2025.103152

Jianfeng Shi , Qian Zhou , Chengsheng Pan

With the rapid development of digital twin technology, the evaluation of its credibility has become a critical issue that needs to be addressed. Existing evaluation methods struggle to effectively cope with the complex and highly dynamic characteristics of digital twins. Therefore, an improved credibility evaluation method based on evidence theory is proposed to enhance the accuracy and reliability of the evaluation results. Firstly, to address the challenge of inconsistent data types across different evaluation metrics in twin models, a cloud model is utilized to generate a unified basic probability assignment, providing a consistent data foundation for the credibility evaluation method. Secondly, to overcome the limitations of traditional evidence theory in handling evidence conflict and uncertainty, an improved evidence theory-based credibility evaluation method is proposed. This method can address conflict resolution and uncertainty expression by incorporating evidence sufficiency and indicator importance. Finally, by effectively integrating multi-source heterogeneous data, this evaluation method enables an accurate evaluation of the credibility of digital twin. Experimental results demonstrate that the proposed method outperforms traditional approaches in handling evidence conflict, providing a more precise evaluation of digital twin credibility, and offering a more reliable basis and evaluation standard for digital twin system design.

随着数字孪生技术的快速发展，其可信性评价成为一个亟待解决的关键问题。现有的评估方法难以有效地应对数字孪生的复杂和高度动态特征。为此，提出了一种改进的基于证据理论的可信度评估方法，以提高评估结果的准确性和可靠性。首先，针对双模型中不同评价指标数据类型不一致的问题，利用云模型生成统一的基本概率赋值，为可信度评价方法提供一致的数据基础；其次，为了克服传统证据理论在处理证据冲突和不确定性方面的局限性，提出了一种改进的基于证据理论的可信度评估方法。该方法通过结合证据充分性和指标重要性来解决冲突解决和不确定性表达。最后，通过对多源异构数据的有效整合，实现了对数字孪生可信度的准确评估。实验结果表明，该方法在处理证据冲突方面优于传统方法，能够更精确地评估数字孪生的可信度，为数字孪生系统设计提供了更可靠的依据和评估标准。

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引用次数: 0

Optimizing IoMT network performance using gateway placement 使用网关布局优化IoMT网络性能

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

Simulation Modelling Practice and Theory

Pub Date : 2025-09-01 Epub Date: 2025-06-07 DOI: 10.1016/j.simpat.2025.103164

R. Mahalakshmi, N. Lalithamani

Gateway Device placement for processing patient data, plays a pivotal role in providing accurate and critical care for patient monitoring and assistance in a connected healthcare system. Long Range Wide Area Network (LoRaWAN) is a wide area network protocol used in providing low-power, seamless communication between the patient health sensors, monitors and the health assistance services in a healthcare network using gateway devices. Objective of the research work is to achieve optimization in the gateway by an adaptive device placement strategy using LoRaWAN thereby improving the network performance. The strategy is a multi-objective optimization, which includes Coverage Maximization, connectivity Optimization, and Energy Minimization for improving the network performance. The gateway placement strategy is verified with the simulation results obtained from Omnet++ Framework for LoRa (FLoRa). The network performance improvement is verified with key metric results observed based on the gateway placement strategy, resulted in Average Energy Consumption being 4.44 mJ, Packet Delivery Ratio (PDR) at 69 %, and Throughput reaching to 481 bps.

用于处理患者数据的网关设备在为连接的医疗保健系统中的患者监测和协助提供准确和关键的护理方面发挥着关键作用。远程广域网（LoRaWAN）是一种广域网协议，用于在使用网关设备的医疗保健网络中的患者健康传感器、监视器和健康辅助服务之间提供低功耗、无缝通信。研究工作的目的是通过采用LoRaWAN的自适应设备放置策略来实现网关的优化，从而提高网络性能。该策略是一个多目标优化，包括覆盖最大化、连通性优化和能量最小化，以提高网络性能。利用omnet++框架对LoRa （FLoRa）的仿真结果验证了网关放置策略。通过基于网关放置策略观察到的关键指标结果验证了网络性能的改进，导致平均能耗为4.44 mJ，分组传递率（PDR）为69%，吞吐量达到481 bps。

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引用次数: 0

A multi-objective deep reinforcement learning algorithm for spatio-temporal latency optimization in mobile IoT-enabled edge computing networks 移动物联网边缘计算网络时空延迟优化的多目标深度强化学习算法

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

Simulation Modelling Practice and Theory

Pub Date : 2025-09-01 Epub Date: 2025-05-27 DOI: 10.1016/j.simpat.2025.103161

Parisa Khoshvaght , Amir Haider , Amir Masoud Rahmani , Farhad Soleimanian Gharehchopogh , Ferzat Anka , Jan Lansky , Mehdi Hosseinzadeh

The rapid increase in Mobile Internet of Things (IoT) devices requires novel computational frameworks. These frameworks must meet strict latency and energy efficiency requirements in Edge and Mobile Edge Computing (MEC) systems. Spatio-temporal dynamics, which include the position of edge servers and the timing of task schedules, pose a complex optimization problem. These challenges are further exacerbated by the heterogeneity of IoT workloads and the constraints imposed by device mobility. The balance between computational overhead and communication challenges is also a problem. To solve these issues, advanced methods are needed for resource management and dynamic task scheduling in mobile IoT and edge computing environments. In this paper, we propose a Deep Reinforcement Learning (DRL) multi-objective algorithm, called a Double Deep Q-Learning (DDQN) framework enhanced with Spatio-temporal mobility prediction, latency-aware task offloading, and energy-constrained IoT device trajectory optimization for federated edge computing networks. DDQN was chosen for its optimize stability and reduced overestimation in Q-values. The framework employs a reward-driven optimization model that dynamically prioritizes latency-sensitive tasks, minimizes task migration overhead, and balances energy efficiency across devices and edge servers. It integrates dynamic resource allocation algorithms to address random task arrival patterns and real-time computational demands. Simulations demonstrate up to a 35 % reduction in end-to-end latency, a 28 % improvement in energy efficiency, and a 20 % decrease in the deadline-miss ratio compared to benchmark algorithms.

移动物联网（IoT）设备的快速增长需要新的计算框架。这些框架必须满足边缘和移动边缘计算（MEC）系统中严格的延迟和能效要求。包括边缘服务器位置和任务调度时间在内的时空动态构成了一个复杂的优化问题。物联网工作负载的异质性和设备移动性所带来的限制进一步加剧了这些挑战。计算开销和通信挑战之间的平衡也是一个问题。为了解决这些问题，需要在移动物联网和边缘计算环境中采用先进的资源管理和动态任务调度方法。在本文中，我们提出了一种深度强化学习（DRL）多目标算法，称为双深度q -学习（DDQN）框架，该框架增强了用于联邦边缘计算网络的时空移动预测、延迟感知任务卸载和能量约束物联网设备轨迹优化。选择DDQN是因为它具有最优的稳定性和较低的q值高估。该框架采用奖励驱动的优化模型，该模型动态地对延迟敏感的任务进行优先级排序，最大限度地减少任务迁移开销，并在设备和边缘服务器之间平衡能源效率。它集成了动态资源分配算法，以解决随机任务到达模式和实时计算需求。仿真表明，与基准算法相比，端到端延迟减少了35%，能源效率提高了28%，截止日期遗漏率降低了20%。

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引用次数: 0

An improved CA model for evacuation simulation in super high-rise buildings: Considering evacuees’ rest on refuge floors and preference for taking evacuation elevators 超高层建筑疏散仿真的改进CA模型：考虑疏散人员在避难层休息和乘坐疏散电梯的偏好

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

Simulation Modelling Practice and Theory

Pub Date : 2025-09-01 Epub Date: 2025-05-21 DOI: 10.1016/j.simpat.2025.103148

Jianfei Huang , Xinnan Liu , Yingbo Ji , Feifan Song , Tengteng Jiang , Tiantian Du , Xin Fan

Most of the previous studies on emergency evacuation simulation in super high-rise buildings have overlooked the role of refuge floors, which are vital for recovery of fatigued evacuees. Additionally, advancements in elevator safety have made evacuation elevators a feasible option as supplementary evacuation facilities to staircases in super high-rise buildings. While some evacuees prefer to take evacuation elevators during emergencies, others still tend to use staircases only. This study proposes an improved cellular automata (CA) model that accounts for the effects of evacuees’ rest on refuge floors and preference for taking evacuation elevators. To build the foundation for setting model parameters of speed recovery after resting on refuge floors, two evacuation experiments are conducted in a super high-rise office building. The improved CA model is developed by incorporating space configurations, updating rules of evacuees and evacuation elevators. Effects of thresholds for taking rest on refuge floors, rest time on refuge floors, ratio of evacuees with different evacuation facility preferences, as well as gender ratio of evacuees on the evacuation efficiency are simulated by the improved CA model. The findings demonstrate that the proposed model can effectively simulate complex evacuation scenarios, including the effects of speed recovery after fatigued evacuees rest on refuge floors and evacuees’ preference for taking evacuation elevators. This study offers valuable insights for optimizing evacuation plans in super high-rise buildings.

以往的超高层建筑应急疏散模拟研究大多忽略了避难层的作用，而避难层对于疲劳疏散人员的恢复至关重要。此外，电梯安全性的进步使得疏散电梯作为超高层建筑楼梯的补充疏散设施成为可行的选择。虽然一些疏散人员在紧急情况下更喜欢乘坐疏散电梯，但其他人仍然倾向于只使用楼梯。本研究提出了一个改进的元胞自动机（CA）模型，该模型考虑了疏散人员在避难楼层休息和乘坐疏散电梯的偏好的影响。为了为避难层休息后速度恢复模型参数的设置奠定基础，在某超高层办公楼进行了两次疏散实验。结合空间配置、疏散人员更新规则和疏散电梯，建立了改进的CA模型。利用改进的CA模型，模拟避难层休息阈值、避难层休息时间、不同避难设施偏好的疏散人员比例以及疏散人员性别比例对疏散效率的影响。研究结果表明，该模型可以有效地模拟复杂的疏散场景，包括疲劳疏散人员在避难层休息后的速度恢复效应和疏散人员对乘坐疏散电梯的偏好。本研究为超高层建筑的疏散方案优化提供了有价值的见解。

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引用次数: 0

Enhanced flame detection in virtual tunnels using DEV-YOLOv8 and digital twin systems 使用DEV-YOLOv8和数字孪生系统增强虚拟隧道中的火焰探测

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

Simulation Modelling Practice and Theory

Pub Date : 2025-09-01 Epub Date: 2025-06-02 DOI: 10.1016/j.simpat.2025.103143

Yongjiang Li , Xingguo Song , Faming Lin , Xu Fang

Highway tunnel fires pose significant safety challenges requiring reliable detection and response strategies. Traditional testing methods face limitations due to insufficient sample diversity and high costs, thus making virtual environments a promising alternative for algorithm development. This study proposes DEV-YOLOv8, an enhanced YOLOv8 model integrated with digital twin technology for flame detection in simulated tunnel environments. The model incorporates three key enhancements: deformable convolutions for adaptive feature extraction, an efficient multi-scale attention mechanism for stable parameter updates, and a cross-stage partial connections module for efficient multi-scale fusion. A Unity-ROS2-based digital twin system enables cost-effective simulation and dataset generation. Experiments demonstrate DEV-YOLOv8’s superiority with 2.2%/1.5%/1.2% improvements in accuracy/recall/[email protected] respectively, while reducing computational cost by 0.8 GFLOPs. The integrated system achieves 98.21% simulation accuracy and 96.19% physical deployment accuracy, with latency differences

<

3.15 ms and RRT delays below 9.91 ms. This work establishes an efficient framework combining deep learning and digital twins for adaptive fire detection in tunnel environments.

公路隧道火灾带来了重大的安全挑战，需要可靠的探测和响应策略。传统的测试方法由于样本多样性不足和成本高而受到限制，因此虚拟环境成为算法开发的一个有希望的替代方案。本研究提出了DEV-YOLOv8，一种集成了数字孪生技术的增强型YOLOv8模型，用于模拟隧道环境中的火焰探测。该模型包含三个关键的改进：用于自适应特征提取的可变形卷积，用于稳定参数更新的高效多尺度注意机制，以及用于高效多尺度融合的跨阶段部分连接模块。基于unity - ros2的数字孪生系统可实现经济高效的模拟和数据集生成。实验证明了DEV-YOLOv8的优势，在准确率/召回率/[email protected]方面分别提高了2.2%/1.5%/1.2%，同时降低了0.8 GFLOPs的计算成本。集成系统的仿真精度为98.21%，物理部署精度为96.19%，时延差异为<；3.15 ms和RRT延迟低于9.91 ms。这项工作建立了一个结合深度学习和数字孪生的有效框架，用于隧道环境中的自适应火灾探测。

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引用次数: 0