Simulation Modelling Practice and Theory最新文献_第2页

Survey of CPU and memory simulators in computer architecture: A comprehensive analysis including compiler integration and emerging technology applications 计算机体系结构中的 CPU 和内存模拟器调查：包括编译器集成和新兴技术应用在内的全面分析

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

Simulation Modelling Practice and Theory

Pub Date : 2024-11-09 DOI: 10.1016/j.simpat.2024.103032

Inseong Hwang , Junghyeok Lee , Huibeom Kang, Gilhyeon Lee, Hyun Kim

In computer architecture studies, simulators are crucial for design verification, reducing research and development time and ensuring the high accuracy of verification results. Several studies have developed and employed a verification environment by designing a custom in-house simulator that verifies the performance improvement of the proposed architecture for each research purpose by integrating multiple simulators or modifying existing ones. Recent advancements in deep neural networks and increased computational complexity have prompted research into emerging technologies, such as GPUs, processing-in-memory (PIM), and neural processing units (NPUs). Recently, custom in-house simulators were developed and actively employed for performance verification. However, constructing proper custom in-house simulators requires a greater grasp of the support functions and characteristics of current architectural simulators, which constitute the backbone of simulator creation. To meet these criteria, a comprehensive comparative analysis was conducted by examining the structures and output metrics supported across various architecture simulators, including representative CPU and memory simulators. Furthermore, it analyzes actual case studies of in-house simulators developed in recent emerging technology research ( i.e., GPUs, NPUs, PIM). Additionally, we examine the characteristics of compilers that support optimization for various recent workloads and simulators by analyzing case studies in which the integration of simulators and compilers has contributed to optimizing the overall simulator operations. Analyzing the overall verification process using these simulators, comparing each component, and confirming actual cases can provide essential insights for selecting and developing simulators suitable for computer architecture research. Consequently, this study contributes to maximizing the accuracy and efficiency of computer architecture research.

在计算机体系结构研究中，模拟器对于设计验证、减少研发时间和确保验证结果的高精度至关重要。有几项研究通过设计定制的内部模拟器，开发并使用了验证环境，通过集成多个模拟器或修改现有模拟器，验证了针对每个研究目的提出的架构的性能改进。深度神经网络的最新进展和计算复杂性的增加促使人们对 GPU、内存处理（PIM）和神经处理单元（NPU）等新兴技术进行研究。最近，人们开发了定制的内部模拟器，并积极用于性能验证。然而，要构建合适的定制内部模拟器，需要进一步掌握当前架构模拟器的支持功能和特点，这些是创建模拟器的基础。为了满足这些标准，我们通过研究各种架构模拟器（包括具有代表性的 CPU 和内存模拟器）所支持的结构和输出指标，进行了全面的比较分析。此外，我们还分析了近期新兴技术研究（如 GPU、NPU、PIM）中开发的内部模拟器的实际案例研究。此外，我们还通过分析模拟器和编译器的集成有助于优化整个模拟器操作的案例研究，考察了支持针对各种最新工作负载和模拟器进行优化的编译器的特性。分析使用这些模拟器的整体验证过程、比较每个组件并确认实际案例，可为选择和开发适合计算机体系结构研究的模拟器提供重要启示。因此，本研究有助于最大限度地提高计算机体系结构研究的准确性和效率。

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引用次数: 0

VM consolidation steps in cloud computing: A perspective review 云计算中的虚拟机整合步骤：透视回顾

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

Simulation Modelling Practice and Theory

Pub Date : 2024-11-09 DOI: 10.1016/j.simpat.2024.103034

Seyyed Meysam Rozehkhani , Farnaz Mahan , Witold Pedrycz

The proliferation of cloud-based applications, data, and services has significantly transformed digital interactions, driven by the widespread use of powerful smart devices and the expansion of cloud ecosystems. These ecosystems rely on data centers composed of Physical Machines (PMs) and Virtual Machines (VMs). The increasing demand for cloud services has led to extensive use of physical servers, resulting in high energy consumption and inefficient resource utilization. Consequently, optimizing resource allocation and reducing power consumption have become pivotal challenges in data center management. A key strategy to address these challenges is Virtual Machine Consolidation (VMC), which optimizes computing resources by consolidating multiple VMs into fewer PMs. This paper comprehensively reviews the three critical phases involved in VMC: PM detection, VM selection, and VM placement. Through an extensive analysis of literature spanning from 2015 to 2024, this review seeks to provide valuable insights into the current landscape of VMC and its potential ramifications on the performance and sustainability of cloud computing. The main flaw in the articles is that the various authors focused on different assessment metrics when the emphasis should have been on the three primary steps in VMC. The importance of this categorization lies in its ability to provide clarity, organization, and a structured framework for comprehending the intricate landscape of VMC. VMC is a multifaceted undertaking encompassing numerous subtasks. Categorization simplifies this complexity by breaking it down into manageable components. Researchers can address each category individually, potentially leading to more focused and effective solutions.

在功能强大的智能设备的广泛使用和云生态系统的扩展推动下，基于云的应用程序、数据和服务的激增极大地改变了数字互动。这些生态系统依赖于由物理机（PM）和虚拟机（VM）组成的数据中心。对云服务日益增长的需求导致物理服务器的广泛使用，造成高能耗和资源利用效率低下。因此，优化资源分配和降低功耗已成为数据中心管理的关键挑战。应对这些挑战的一个关键策略是虚拟机整合（VMC），它通过将多个虚拟机整合到更少的 PM 中来优化计算资源。本文全面回顾了 VMC 所涉及的三个关键阶段：PM 检测、虚拟机选择和虚拟机放置。通过对 2015 年至 2024 年期间的文献进行广泛分析，本综述力图为 VMC 的现状及其对云计算性能和可持续性的潜在影响提供有价值的见解。这些文章的主要缺陷在于，不同作者关注的是不同的评估指标，而重点本应放在 VMC 的三个主要步骤上。这种分类的重要性在于它能够提供清晰度、组织性和结构化框架，以便理解 VMC 的复杂情况。虚拟多媒体中心是一项多方面的工作，包含众多子任务。通过将其分解为易于管理的组成部分，分类简化了这种复杂性。研究人员可以逐一解决每个类别的问题，从而找到重点更突出、更有效的解决方案。

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引用次数: 0

Model checking spatial reachability specifications of public transport networks 公共交通网络空间可达性规范的模型检查

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

Simulation Modelling Practice and Theory

Pub Date : 2024-11-07 DOI: 10.1016/j.simpat.2024.103033

Jun Niu , Jia Wang

Well-designed spatial configurations of public transport stops and routes in big cities contribute to enhancing daily travel services for citizens, effectively mitigating traffic congestion, and addressing other pertinent challenges. When examining spatial layouts of public transport networks (PTNs), various reachability demands between stops or urban Points of Interest (POIs) are crucial issues should be firstly taken into account. Existing methods to investigate spatial reachability properties of PTNs generally need to construct some evaluation functions, or survey reachability metrics through some network analysis techniques. These methods are often impractical, as the functional relations always cannot be accurately defined, or some global network metrics cannot provide explicit evidences for PTN layout planning or optimization.

In this paper, we introduce spatial model checking techniques to the formal verification of the reachability specifications of PTN to guarantee the rationality of PTN layout. First, we extend closure space structure by incorporating attribute labeling functions and logical propositions for public transport stops and routes to develop a formal spatial verification model for PTN spatial layout. Second, we propose several novel reachability operators based on the logical operators of the Spatial Logic for Closure Space (SLCS) to facilitate the logical characterization of reachability specifications. Third, we perform the verification of the transformed reachability formulas by the spatial model checker topochecker. Examples demonstrate the effectiveness of our approach and indicate that it can perform automatic, descriptive and comprehensible verification of the reachability properties PTN layouts.

设计合理的大城市公共交通站点和线路空间布局有助于提高市民的日常出行服务，有效缓解交通拥堵，并应对其他相关挑战。在研究公共交通网络（PTN）的空间布局时，应首先考虑站点或城市兴趣点（POI）之间的各种可达性需求。现有研究公共交通网络空间可达性属性的方法一般需要构建一些评价函数，或通过一些网络分析技术来调查可达性指标。本文将空间模型检查技术引入到 PTN可达性规范的形式验证中，以保证 PTN 布局的合理性。首先，我们扩展了闭包空间结构，加入了公共交通站点和线路的属性标注函数和逻辑命题，从而建立了公共交通网络空间布局的形式化空间验证模型。其次，我们在闭合空间空间逻辑（SLCS）逻辑算子的基础上提出了几种新型可达性算子，以促进可达性规范的逻辑表征。第三，我们通过空间模型检查器 topochecker 对转换后的可达性公式进行验证。示例证明了我们方法的有效性，并表明它可以自动、描述性和可理解地验证 PTN 布局的可达性属性。

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引用次数: 0

End-to-end latency upper bounds and service chain deployment algorithm based on industrial internet network 基于工业互联网络的端到端延迟上限和服务链部署算法

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

Simulation Modelling Practice and Theory

Pub Date : 2024-11-06 DOI: 10.1016/j.simpat.2024.103031

Min Wang , Ziyi Gao , Haoyuan Wang , Sibo Qiao , Jinhai Wang

The diverse service requests in industrial Internet networks require flexible and efficient service chain deployment to ensure the quality of service (QoS). However, current deployment algorithms for service chains are primarily designed to guarantee only low end-to-end latency; they often overlook the amount of service chains that can be accommodated by the network and could lead to severe network load imbalances, significantly reducing service efficiency and causing serious network congestion issues. To address the above issues, we develop a mathematical model of the network topology and service request chains by integrating Network Function Virtualization (NFV) and Software Defined Networking (SDN). Utilizing network calculus theory, we derive the upper bound of end-to-end delay for service chain routing and analyzed the relationship between the upper bound of service chain routing delay and the resource allocation of Virtual Network Function (VNF) nodes. Based on the aforementioned model, we propose a novel service chain deployment algorithm named the Delay-Aware Load-Balanced Routing Algorithm (DLBRA). DLBRA comprehensively considers network traffic load balancing and end-to-end latency of service chains, rationally allocating VNF node resources to complete the determined service chain routing deployment. Experimental results indicate that, compared to the shortest path and load balancing algorithms, DLBRA not only ensures that the end-to-end delay of the service chain meets its QoS requirements, but also effectively reduces network load imbalance, significantly increasing the number of service chain requests that the network can accommodate. Additionally, DLBRA provides tailored deployment guidance for different types of service chains, such as latency-sensitive and data-intensive service chains, ensuring optimal utilization of network resources. This algorithm enhances the efficiency of service chain deployment in industrial internet scenarios and possesses broad application potential in other network environments where delay optimization and load balancing are critical, such as intelligent transportation, cloud computing, and 5G networks.

工业互联网络中的服务请求多种多样，需要灵活高效的服务链部署来确保服务质量（QoS）。然而，目前的服务链部署算法主要是为了保证较低的端到端延迟，往往忽略了网络可容纳的服务链数量，可能导致严重的网络负载失衡，大大降低服务效率，造成严重的网络拥塞问题。针对上述问题，我们结合网络功能虚拟化（NFV）和软件定义网络（SDN），建立了网络拓扑和服务请求链的数学模型。利用网络微积分理论，我们推导出了服务链路由的端到端延迟上限，并分析了服务链路由延迟上限与虚拟网络功能（VNF）节点资源分配之间的关系。基于上述模型，我们提出了一种新的服务链部署算法，名为 "延迟感知负载均衡路由算法（Delay-Aware Load-Balanced Routing Algorithm，DLBRA）"。DLBRA综合考虑了网络流量负载均衡和服务链的端到端时延，合理分配VNF节点资源，完成确定的服务链路由部署。实验结果表明，与最短路径算法和负载均衡算法相比，DLBRA 不仅能确保服务链的端到端延迟满足其 QoS 要求，还能有效降低网络负载不平衡，显著增加网络可容纳的服务链请求数量。此外，DLBRA 还能为不同类型的服务链（如延迟敏感型和数据密集型服务链）提供量身定制的部署指导，确保网络资源得到最佳利用。该算法提高了工业互联网场景中服务链的部署效率，并在智能交通、云计算和 5G 网络等对延迟优化和负载平衡要求较高的其他网络环境中具有广泛的应用潜力。

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引用次数: 0

Do the sparser access points have less impact on arterial traffic? A microscopic simulation-based study 出入口越少对干道交通的影响越小吗？基于微观模拟的研究

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

Simulation Modelling Practice and Theory

Pub Date : 2024-11-06 DOI: 10.1016/j.simpat.2024.103036

Jing Zhao , Yulan Xia , Chaojun Wang , Jairus Odawa

A dynamic microscopic traffic flow simulation within a ring arterial context was developed to investigate the effects of access point spacing on urban arterial flow under a right-in-right-out access management system. The microscopic traffic flow model, centered on car-following and lane-changing behaviors, was established based on vehicle interactions. The car-following aspect encompasses free driving, car-following behavior, and deceleration and braking states while lane-changing considerations include decision-making and acceptable gap assessment. Experimental scenarios account for arterial traffic density, access traffic demand intensity, average access point spacing, and variation coefficient of access point spacing. The traffic flow and speeds within the ring arterial were evaluated across 5040 operational conditions (equating to 5880 simulation hours). The traffic flow trends and speed variations with density across different access spacing scenarios were analyzed. We made an intriguing discovery: the impact on arterial traffic flow increases with larger average access point spacing, challenging conventional traffic planning recommendations that advocate for greater spacing. Additionally, access traffic minimally affects the overall arterial flow when arterial traffic volume is low. By highlighting these critical insights, this study introduces novel considerations for designing and managing access points.

本研究开发了环形干道背景下的动态微观交通流模拟，以研究在右进右出通行管理系统下，出入口间距对城市干道交通流的影响。微观交通流模型以车辆跟车和变道行为为中心，建立在车辆相互作用的基础上。跟车方面包括自由驾驶、跟车行为以及减速和制动状态，而变道考虑因素包括决策和可接受间隙评估。实验方案考虑了干道交通密度、出入口交通需求强度、平均出入口间距以及出入口间距的变化系数。在 5040 种运行条件下（相当于 5880 个模拟小时），对环形干道内的交通流量和车速进行了评估。分析了不同接入点间距情况下的交通流量趋势和速度随密度的变化。我们发现了一个有趣的现象：平均出入口间距越大，对干道交通流量的影响就越大，这对主张加大间距的传统交通规划建议提出了挑战。此外，当干道交通流量较低时，入口交通对整个干道交通流量的影响也很小。通过强调这些重要的见解，本研究为出入口的设计和管理引入了新的考虑因素。

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引用次数: 0

A cellular automata model of a laser reproducing laser passive and active Q-Switching 再现激光器无源和有源 Q 开关的细胞自动机模型

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

Simulation Modelling Practice and Theory

Pub Date : 2024-11-01 DOI: 10.1016/j.simpat.2024.103028

Francisco Jiménez-Morales , José-Luis Guisado-Lizar , José Manuel Guerra

The Q-switching (QS) phenomenon in lasers refers to the production of high intensity pulses by means of a saturable absorber (passive method) or by modifying the reflectivity or losses of the intracavity optics or mirrors (active method). Theoretically, the QS is studied through the laser rate equations which are useful to predict, at least qualitatively and roughly, the fundamental aspects of laser dynamics. However, specific details such as the spatial distribution of the intensity of the laser emission escape the simplicity of the rate equations. In this work we present a two dimensional cellular automata model (CA) to study the QS phenomenology for both the passive and the active method. To simulate the passive method we consider a spatial distribution of cells whose physical properties emulate those of the saturable adsorbers. And for the active method we introduce a periodic modulation of the lifetime of the photons inside the cavity. We have done numerous numerical simulations that show that despite the simplicity of the evolution rules, the AC model is capable of obtaining the main dynamics of operation of the laser by modifying the system parameters such as the pumping probability and the properties of the absorber.

激光器中的 Q 开关（QS）现象是指通过可饱和吸收器（被动方法）或改变腔内光学器件或反射镜的反射率或损耗（主动方法）产生高强度脉冲。从理论上讲，QS 是通过激光速率方程进行研究的，这些方程至少可以定性和粗略地预测激光动力学的基本方面。然而，激光发射强度的空间分布等具体细节却无法摆脱速率方程的简单性。在这项工作中，我们提出了一个二维蜂窝自动机模型（CA），用于研究被动和主动方法的 QS 现象。为了模拟被动方法，我们考虑了细胞的空间分布，其物理特性模拟了可饱和吸附器的物理特性。而在主动方法中，我们引入了对空腔内光子寿命的周期性调制。我们进行了大量的数值模拟，结果表明，尽管演化规则很简单，但交流模型能够通过修改系统参数（如泵浦概率和吸收体的特性）获得激光器的主要运行动态。

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引用次数: 0

Advanced network design for 6G: Leveraging graph theory and slicing for edge stability 先进的6G网络设计：利用图论和切片边缘稳定性

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

Simulation Modelling Practice and Theory

Pub Date : 2024-10-28 DOI: 10.1016/j.simpat.2024.103029

Mantisha Gupta (IEEE Student Member) , Rakesh Kumar Jha (IEEE Senior Member)

The advent of 6 G networks will emphasize AR/VR-based tactile internet and touch-enabled services, requiring solutions to address latency and reliability issues in tactile data perception, particularly in edge networking. This article highlights the critical role of graph theory in improving network design for both symmetric and randomly deployed networks, and it emphasizes the importance of network slicing in managing densely connected edge networks. These networks typically consist of numerous edge devices that enable data transfer to higher layers, enhancing connectivity and ensuring network stability within a confined range. The paper compares the accuracy of conventional networks before and after implementing network slicing, with the goal of increasing reliability by dividing the edge network into segments, thereby reducing computation time. The study proposes a method for optimal node segregation and path determination in edge networks using both uniform and random network slicing. Network performance is assessed using metrics such as computation time and node failure rate. The paper concludes that network slicing is the most effective design approach for touch technology interfaces within 6 G and IoT frameworks.

6 G网络的出现将强调基于AR/ vr的触觉互联网和触摸服务，需要解决触觉数据感知中的延迟和可靠性问题，特别是在边缘网络中。本文强调了图论在改进对称和随机部署网络的网络设计中的关键作用，并强调了网络切片在管理密集连接的边缘网络中的重要性。这些网络通常由许多边缘设备组成，这些设备可以将数据传输到更高层，增强连接性并确保在有限范围内的网络稳定性。本文比较了传统网络在实施网络切片之前和之后的准确率，目的是通过将边缘网络分段来提高可靠性，从而减少计算时间。研究提出了一种基于均匀和随机网络切片的边缘网络最优节点隔离和路径确定方法。使用计算时间和节点故障率等指标来评估网络性能。本文的结论是，网络切片是在6 G和物联网框架中最有效的触摸技术接口设计方法。

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引用次数: 0

Simulation-based evaluation of advanced threat detection and response in financial industry networks using zero trust and blockchain technology 利用零信任和区块链技术对金融业网络中的高级威胁检测和响应进行基于仿真的评估

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

Simulation Modelling Practice and Theory

Pub Date : 2024-10-24 DOI: 10.1016/j.simpat.2024.103027

Clement Daah, Amna Qureshi, Irfan Awan, Savas Konur

The financial sector is increasingly facing advanced cyber threats, necessitating a shift from traditional security measures to more dynamic frameworks. This study presents a novel integration of Zero Trust architecture with hybrid access control system and blockchain technology to enhance security in financial institutions. Zero Trust enforces continuous authentication and dynamic access controls, while blockchain secures digital identities and transaction logs through its immutable ledger, ensuring data integrity and non-repudiation. The proposed framework, evaluated using OMNeT++ simulations enhanced by Ethereum-Ganache, shows improved detection accuracy, reduced false positives, and increased resistance to insider threats and other attacks. It also strengthens compliance with regulatory requirements through robust audit trails, providing enhanced protection for sensitive financial data.

金融业正日益面临先进的网络威胁，因此有必要从传统的安全措施转向更动态的框架。本研究介绍了零信任架构与混合访问控制系统和区块链技术的新型集成，以增强金融机构的安全性。零信任实施持续身份验证和动态访问控制，而区块链通过其不可变的分类账确保数字身份和交易日志的安全，从而确保数据的完整性和不可抵赖性。利用以太坊-Ganache 增强的 OMNeT++ 仿真对所提出的框架进行了评估，结果表明，该框架提高了检测准确性，减少了误报，并增强了对内部威胁和其他攻击的抵御能力。它还通过强大的审计跟踪功能加强了对监管要求的合规性，为敏感金融数据提供了更强的保护。

引用次数: 0

Simulation-based adaptive optimization for passenger flow control measures at metro stations 地铁站客流控制措施的仿真自适应优化

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

Simulation Modelling Practice and Theory

Pub Date : 2024-10-24 DOI: 10.1016/j.simpat.2024.103021

Yiqi Zhou , Maohua Zhong , Zhongwen Li , Xuan Xu , Fucai Hua , Rongliang Pan

Effective passenger flow control measures are essential for the safe operation of metro stations. Existing in-station control measures include adjusting the operation mode of escalators and setting up temporary fences. However, in practice, metro operators often adopt fixed operation modes during fixed periods, indicating that the current passenger flow control measures at metro stations are overly rigidified. Therefore, developing an adaptive control strategy to constantly balance the wildly fluctuating passenger flow and optimize the operation performance is a key issue in current research. In this study, transportation efficiency and congestion risk are selected as evaluation objectives for passenger transportation risk, and passenger flow feature, station structure, and passenger flow control measures are considered key influential factors. Subsequently, an adaptive optimization method integrating simulation and data interpolation is proposed. The software Legion is used to conduct 150 orthogonal simulations, and prediction models for passenger transportation risk are obtained by performing data interpolation on the simulation results. Finally, taking a certain metro station as a case study, the optimal passenger flow control strategy under any passenger flow composition is obtained by scenario acquisition, risk identification, and adaptive decision-making. The results show that setting up temporary fences can reduce the passenger density near the fare gates, while adjusting the running direction of escalators can reduce overcrowding on the platform. Under varying passenger flow composition, the optimal strategy for the current scenario can be obtained, controlling passenger transportation risk within an acceptable range and providing assistance for metro operators in decision-making.

有效的客流控制措施对地铁站的安全运营至关重要。现有的站内控制措施包括调整自动扶梯的运行模式和设置临时围栏。然而，在实际操作中，地铁运营商往往会在固定时段采用固定的运行模式，这表明目前地铁站内的客流控制措施过于僵化。因此，开发一种自适应控制策略来不断平衡剧烈波动的客流并优化运营性能是当前研究的一个关键问题。本研究选择运输效率和拥堵风险作为客流运输风险的评价目标，并将客流特征、车站结构和客流控制措施作为关键影响因素。随后，提出了一种集模拟和数据插值于一体的自适应优化方法。利用软件 Legion 进行 150 次正交模拟，通过对模拟结果进行数据插值，得到客运风险预测模型。最后，以某地铁站为例，通过场景获取、风险识别、自适应决策等方法，得到了任意客流构成下的最优客流控制策略。结果表明，设置临时围栏可以降低检票口附近的客流密度，而调整自动扶梯的运行方向则可以减少站台上的拥挤现象。在客流构成变化的情况下，可以得到当前场景下的最优策略，将客运风险控制在可接受的范围内，为地铁运营商的决策提供帮助。

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引用次数: 0

Dual-timescale resource management for multi-type caching placement and multi-user computation offloading in Internet of Vehicle 车联网中用于多类型缓存放置和多用户计算卸载的双时间尺度资源管理

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

Simulation Modelling Practice and Theory

Pub Date : 2024-10-23 DOI: 10.1016/j.simpat.2024.103025

Dun Cao , Bo Peng , Yubin Wang , Fayez Alqahtani , Jinyu Zhang , Jin Wang

In Internet of Vehicle (IoV), edge computing can effectively reduce task processing delays and meet the real-time needs of connected-vehicle applications. However, since the requirements for caching and computing resources vary across heterogeneous vehicle requests, a new challenge is posed on the resource management in the three-tier cloud–edge–end architecture, particularly when multi users offload tasks in the same time. Our work comprehensively considers various scenarios involving the deployment of multiple caching types from multi-users and the distinct time scales of offloading and updating, then builds a joint optimization caching placement, computation offloading and computational resource allocation model, aiming to minimize overall latency. Meanwhile, to better solving the model, we propose the Multi-node Collaborative Caching, Offloading, and Resource Allocation Algorithm (MCCO-RAA). MCCO-RAA utilizes dual time scales to optimize the problem: employing a Bellman optimization idea-based multi-node collaborative greedy caching placement strategy at large time scales, and a computational offloading and resource allocation strategy based on a two-tier iterative Deep Deterministic Policy Gradient (DDPG) and cooperative game at small time scales. Experimental results demonstrate that our proposed scheme achieves a 28% reduction in overall system latency compared to the baseline scheme, with smoother latency variations under different parameters.

在车联网（IoV）中，边缘计算可以有效减少任务处理延迟，满足车联网应用的实时需求。然而，由于异构车辆请求对缓存和计算资源的要求各不相同，这对三层云-边缘-端架构的资源管理提出了新的挑战，尤其是当多用户同时卸载任务时。我们的工作综合考虑了多用户部署多种缓存类型的各种场景，以及卸载和更新的不同时间尺度，然后建立了一个联合优化缓存放置、计算卸载和计算资源分配的模型，旨在最大限度地减少整体延迟。同时，为了更好地求解该模型，我们提出了多节点协同缓存、卸载和资源分配算法（MCCO-RAA）。MCCO-RAA 利用双时间尺度来优化问题：在大时间尺度上采用基于贝尔曼优化思想的多节点协作贪婪缓存放置策略，在小时间尺度上采用基于双层迭代深度确定性策略梯度（DDPG）和合作博弈的计算卸载和资源分配策略。实验结果表明，与基线方案相比，我们提出的方案使系统整体延迟时间减少了 28%，并且在不同参数下延迟时间的变化更加平滑。

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引用次数: 0