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Developing Environment of Hierarchical and Distributed Real-Time Fire-Control Network 被引量:1
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作者 He Jianhua(Northwestern Polytechnical University, Xi’an 710072, P. R. China)(This project was supported by the Astronautics Foundation.) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第4期1-7,共7页
This paper introduces a hierarchical real-time environment for developing ship-bornefire-control system. Advanced computer networks are used to simulate the system with the requiredengagement scenario, including own-s... This paper introduces a hierarchical real-time environment for developing ship-bornefire-control system. Advanced computer networks are used to simulate the system with the requiredengagement scenario, including own-ship and parameters, and data processing and transmission,mission calculation, graphical supervision and gunnery ballistics outputting. The simulation systemis able to receive instruction from, or send information to the command-control center. Furthermore,the system can also be used to compare various designed schemes and analyze the accuracy andeffectiveness of the system. 展开更多
关键词 Distributed network Fire-control RS-485 communication Software environment
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SFC placement and dynamic resource allocation based on VNF performance-resource function and service requirement in cloud-edge environment
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作者 HAN Yingchao MENG Weixiao FAN Wentao 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期906-921,共16页
With the continuous development of network func-tions virtualization(NFV)and software-defined networking(SDN)technologies and the explosive growth of network traffic,the requirement for computing resources in the netw... With the continuous development of network func-tions virtualization(NFV)and software-defined networking(SDN)technologies and the explosive growth of network traffic,the requirement for computing resources in the network has risen sharply.Due to the high cost of edge computing resources,coordinating the cloud and edge computing resources to improve the utilization efficiency of edge computing resources is still a considerable challenge.In this paper,we focus on optimiz-ing the placement of network services in cloud-edge environ-ments to maximize the efficiency.It is first proved that,in cloud-edge environments,placing one service function chain(SFC)integrally in the cloud or at the edge can improve the utilization efficiency of edge resources.Then a virtual network function(VNF)performance-resource(P-R)function is proposed to repre-sent the relationship between the VNF instance computing per-formance and the allocated computing resource.To select the SFCs that are most suitable to deploy at the edge,a VNF place-ment and resource allocation model is built to configure each VNF with its particular P-R function.Moreover,a heuristic recur-sive algorithm is designed called the recursive algorithm for max edge throughput(RMET)to solve the model.Through simula-tions on two scenarios,it is verified that RMET can improve the utilization efficiency of edge computing resources. 展开更多
关键词 cloud-edge environment virtual network function(VNF)performance-resource(P-R)function edge resource allo-cation
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Opportunistic spectrum sharing in software defined wireless network
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作者 Mao Yang Yong Li +2 位作者 Depeng Jin Li Su Lieguang Zeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期934-941,共8页
Over the past few decades, the world has witnessed a rapid growth in mobile and wireless networks(MWNs) which significantly change human life. However, proliferating mobile demands lead to several intractable challe... Over the past few decades, the world has witnessed a rapid growth in mobile and wireless networks(MWNs) which significantly change human life. However, proliferating mobile demands lead to several intractable challenges that MWN has to face. Software-defined network is expected as a promising way for future network and has captured growing attention. Network virtualization is an essential feature in software-defined wireless network(SDWN), and it brings two new entities, physical networks and virtual networks. Accordingly, efficiently assigning spectrum resource to virtual networks is one of the fundamental problems in SDWN. Directly orienting towards the spectrum resource allocation problem, firstly, the fluctuation features of virtual network requirements in SDWN are researched, and the opportunistic spectrum sharing method is introduced to SDWN. Then, the problem is proved as NP-hardness. After that, a dynamic programming and graph theory based spectrum sharing algorithm is proposed.Simulations demonstrate that the opportunistic spectrum sharing method conspicuously improves the system performance up to around 20%–30% in SDWN, and the proposed algorithm achieves more efficient performance. 展开更多
关键词 software-defined network(SDN) wireless virtualiza-tion opportunistic spectrum sharing dynamic programming graph theory
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Research on Application Technology Oriented Rapid Response Manufacturing in the Distributed Network Environment
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作者 JIN Ji-wen, NI Yan-rong, XI Jun-tong, FAN Fei-ya, JIN Ye (CIM Institute, Department of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200030, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期43-44,共2页
A new chance of developing traditional manufacturing industry comes forth with the development of network technology. Application technology oriented rapid response manufacturing in the distributed network environment... A new chance of developing traditional manufacturing industry comes forth with the development of network technology. Application technology oriented rapid response manufacturing in the distributed network environments, that is, how to take advantage of the Intranet and Internet, combine the numerous manufacturing resources spread around the region, the country and even the globe is the key to the agile design, manufacturing and the buildup of comprehensively competitive power, at the same time, is also an important research direction in the field of advanced manufacturing technology. Rapid response manufacturing in the distributed network environment is a newly manufactory pattern that can be used to implement the conception of agile design and manufacturing, but there are some new problems coming with it, which will directly influence the enterprise’s ability of rapid response in the distributed network manufacturing pattern and lead to the failure of the league and the lost of the given orders. In this paper, we establish some approaches to solve these problems in product development process. The paper then presents the research on key application technologies and solutions includes: network safety strategy which guarantees data transferring among the leaguer members, production data management based on Web/DOT (Distributed Object Technology) and XML criteria which guarantees data exchange in structure-variance characteristic environments, the network platform which provides the conversion service of different types of CAD files each other. All of these solutions are aim for technology problems existing in the distributed network environments and among the league members. Finally, the paper takes one project, that is, the establishment of the online application service system for Shanghai Advance Manufacturing Technology Research Center as a good instance. 展开更多
关键词 distributed network environment rapid response manufacturing data exchange
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Detection of geohazards caused by human disturbance activities based on convolutional neural networks
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作者 ZHANG Heng ZHANG Diandian +1 位作者 YUAN Da LIU Tao 《水利水电技术(中英文)》 北大核心 2025年第S1期731-738,共8页
Human disturbance activities is one of the main reasons for inducing geohazards.Ecological impact assessment metrics of roads are inconsistent criteria and multiple.From the perspective of visual observation,the envir... Human disturbance activities is one of the main reasons for inducing geohazards.Ecological impact assessment metrics of roads are inconsistent criteria and multiple.From the perspective of visual observation,the environment damage can be shown through detecting the uncovered area of vegetation in the images along road.To realize this,an end-to-end environment damage detection model based on convolutional neural network is proposed.A 50-layer residual network is used to extract feature map.The initial parameters are optimized by transfer learning.An example is shown by this method.The dataset including cliff and landslide damage are collected by us along road in Shennongjia national forest park.Results show 0.4703 average precision(AP)rating for cliff damage and 0.4809 average precision(AP)rating for landslide damage.Compared with YOLOv3,our model shows a better accuracy in cliff and landslide detection although a certain amount of speed is sacrificed. 展开更多
关键词 convolutional neural network DETECTION environment damage CLIFF LANDSLIDE
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Quality Assessment by Evaluation of Network-based Teaching Environments
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作者 Wolfram Laaser 《开放教育研究》 CSSCI 2005年第2期59-64,共6页
This paper introduced the objectives, instruments and methods for the evaluation firstly, Then the paper exemplified the criteria to evaluate the learntng management system and online courses. At the end, the author c... This paper introduced the objectives, instruments and methods for the evaluation firstly, Then the paper exemplified the criteria to evaluate the learntng management system and online courses. At the end, the author came the conclusion that the results of evaluation should be implemented continuously to implore the systems services and submitted to the scientific community to check their rigidity and validity. 展开更多
关键词 教学环境 教学质量 教学评估 远程开放教育
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Multi-agent-based Approach for Determination of Time-quota in Integrated Environment
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作者 LI Shu-juan, LI Yan, ZHENG Jian-ming, XIAO Ji-ming, HONG Wei (The Mechanical and Instrument Engineering School, Xi’an University of Technology, Xi’an 710048, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期156-157,共2页
Time-quota is one of important factors in producti on system. It is affected by various factors. time-quota is studied in CAPP and p roduction schedule integration environment in this paper. An agent-based time- quota... Time-quota is one of important factors in producti on system. It is affected by various factors. time-quota is studied in CAPP and p roduction schedule integration environment in this paper. An agent-based time- quota method is put forward and the structure model is established by means of i ntelligent agent in integrated environment. The method can map the influencing t ime-quota factors into part agent related to process state and machine method a gent, resorting to the function of agent rule-based reasoning, the agents can t ransform these factors into data mode that artificial neural network (ANN) can a ccept and recognize. As a tool, ANN agent can calculate time-quota quickly. A b lackboard method is used as the means of communication and collaborative control between agents. The experiments show that precise process time-quota can be obtained rapidly with proper samples selected, continuous self-study and self -organization in system, and multi-agent approach is an effective method for d etermination of time-quota. 展开更多
关键词 MULTI-AGENT artificial neural network (ANN) ti me-quota integrated environment
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Machining process model based on virtual reality environment
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作者 王太勇 汪文津 +2 位作者 汪文颖 范胜波 罗珺 《Journal of Central South University》 SCIE EI CAS 2005年第S2期34-40,共7页
Virtual manufacturing is fast becoming an affordable technology with wide-ranging applications in modern manufacturing. Its advantages over existing technology are primarily that users can visualize, feel involvement ... Virtual manufacturing is fast becoming an affordable technology with wide-ranging applications in modern manufacturing. Its advantages over existing technology are primarily that users can visualize, feel involvement and interact with virtual representations of real world activities in real time. In this paper, a virtual cutting system is built which can simulate turning process, estimate tool wear and cutting force using artificial neural network etc. Using the simulated machining environment in virtual reality (VR), the user can practise and preview the operations for possible problems that might occur during implementation. This approach enables designers to evaluate and design feasible machining processes in a consistent manner as early as possible during the development process. 展开更多
关键词 virtual manufacturing environment NC graphics verification artificial neural network tool wear estimation model cutting force prediction model
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SUNDER:Self-organized grouping and entrapping method for swarms in multitarget environments
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作者 Yutong Yuan Zhun Fan +5 位作者 Xiaomin Zhu Li Ma Ji Ouyang Weidong Bao Ji Wang Zhaojun Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第8期68-83,共16页
For swarm robots moving in a harsh or uncharted outdoor environment without GPS guidance and global communication,algorithms that rely on global-based information are infeasible.Typically,traditional gene regulatory n... For swarm robots moving in a harsh or uncharted outdoor environment without GPS guidance and global communication,algorithms that rely on global-based information are infeasible.Typically,traditional gene regulatory networks(GRNs)that achieve superior performance in forming trapping pattern towards targets require accurate global positional information to guide swarm robots.This article presents a gene regulatory network with Self-organized grouping and entrapping method for swarms(SUNDER-GRN)to achieve adequate trapping performance with a large-scale swarm in a confined multitarget environment with access to only local information.A hierarchical self-organized grouping method(HSG)is proposed to structure subswarms in a distributed way.In addition,a modified distributed controller,with a relative coordinate system that is established to relieve the need for global information,is leveraged to facilitate subswarms entrapment toward different targets,thus improving the global multi-target entrapping performance.The results demonstrate the superiority of SUNDERGRN in the performance of structuring subswarms and entrapping 10 targets with 200 robots in an environment confined by obstacles and with only local information accessible. 展开更多
关键词 Swarm robots Local information Gene regulatory network Swarm grouping Trapping pattern Confined multitarget environment
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考虑多重异质性的区域环境合作治理小世界网络演化博弈研究 被引量:1
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作者 范如国 吴婷 《管理工程学报》 北大核心 2025年第1期140-154,共15页
由于环境污染具有负外部性,跨区域的环境问题不断涌现,因此,地方政府之间的合作治理是化解区域环境问题的重要路径,也是未来中国区域环境治理的发展方向。本文基于复杂网络理论、演化博弈理论,考虑地方政府间的偏好异质性和收入异质性,... 由于环境污染具有负外部性,跨区域的环境问题不断涌现,因此,地方政府之间的合作治理是化解区域环境问题的重要路径,也是未来中国区域环境治理的发展方向。本文基于复杂网络理论、演化博弈理论,考虑地方政府间的偏好异质性和收入异质性,引入权重来刻画不同地区在合作中的贡献度的差异,并纳入收益分配机制、违约金机制,构建了加权NW小世界网络上地方政府间合作治理的演化博弈模型;通过数值仿真,分析了合作收益和成本、违约金、异质性三方面对网络合作水平的影响。研究结果表明:合作收益增加与合作成本降低均能促进地方政府合作治理网络向着帕累托最优方向演化,且当合作收益和合作成本到达一定水平时,经济发展水平低的地区对合作收益和合作成本的变化更为敏感。适当的违约金可以促进地方政府合作行为的演化,但违约金只是起到保障和制约的作用,仅提高违约金难以促进合作策略全扩散。节点异质性对于提高地方政府区域合作治理水平是一把双刃剑。 展开更多
关键词 复杂网络 演化博弈 区域环境 合作治理 异质性
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山火作用下架空输电导线智能监测技术研究综述 被引量:2
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作者 王炯 缪煦扬 +3 位作者 朱太云 张佳庆 孙韬 何青 《智慧电力》 北大核心 2025年第5期48-54,共7页
山火等灾害严重威胁着架空输电导线的安全。通过在线监测技术实时获取架空输电导线的状态参数,及时采取有效预防措施,以确保架空输电导线安全、保障电力供应。分析了山火灾害下架空输电导线的监测特点和要求,对测点的分布式布置和监测... 山火等灾害严重威胁着架空输电导线的安全。通过在线监测技术实时获取架空输电导线的状态参数,及时采取有效预防措施,以确保架空输电导线安全、保障电力供应。分析了山火灾害下架空输电导线的监测特点和要求,对测点的分布式布置和监测数据的无线传输等技术的研究进展进行了综述。为了对架空输电导线在山火灾害下的危险点进行有效监测,分析对比了不同监测技术在架空输电导线测点部署中的优缺点,提出合理布置测点、选择先进的通信方式、构建稳定高效的网络结构等优化措施,以确保监测数据的快速安全传输。面对山火等灾害的挑战,未来对架空输电导线监测技术的研究应着眼于提高监测系统的有效性及其智能化水平和快速数据分析处理能力。 展开更多
关键词 架空输电导线 环境资源 山火灾害 危险点 监测 无线传输 传感器网络
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中国省际营商环境空间网络结构分析:基于自由贸易试验区视角 被引量:3
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作者 苏振东 宫硕 李卓平 《大连理工大学学报(社会科学版)》 北大核心 2025年第1期26-36,共11页
优化营商环境是深化改革、发展更高水平开放型经济的重要保障。使用熵权法构建2004~2018年中国省际营商环境评价指标,通过改进的引力模型和社会网络分析方法对我国省际营商环境空间网络关联结构进行分析,最后利用QAP方法深入定量考察影... 优化营商环境是深化改革、发展更高水平开放型经济的重要保障。使用熵权法构建2004~2018年中国省际营商环境评价指标,通过改进的引力模型和社会网络分析方法对我国省际营商环境空间网络关联结构进行分析,最后利用QAP方法深入定量考察影响我国省际营商环境空间关联网络结构的成因。研究发现:我国省际营商环境空间关联网络呈现倒“U”型的空间分布,并以上海、江苏、北京、浙江、福建为核心地区构成交错复杂的空间网络;自由贸易试验区(简称自贸区)建设对我国省际营商环境空间关联网络结构产生显著的正向影响,尤以对南部地区以及内陆地区的影响更为明显;自贸区设立通过提升软环境、社会服务、市场环境、基础设施的空间关联程度,促进省际营商环境空间关联网络结构的优化。 展开更多
关键词 自贸区 营商环境 社会网络分析方法 QAP回归
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基于MR-VOD的神农架林区野生动物视频检测 被引量:1
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作者 眭海刚 魏天怡 +2 位作者 胡烈云 杨敬元 马国飞 《野生动物学报》 北大核心 2025年第1期1-13,共13页
红外相机视频是野生动物调查的主流研究方法之一,但在林区受设备角度、复杂环境与野生动物活动的随机性影响,极易出现检测中光流捕捉错误或简单语义难以识别的情况。针对此类问题,提出一种基于多帧关系网络特征增强的视频目标检测方法(m... 红外相机视频是野生动物调查的主流研究方法之一,但在林区受设备角度、复杂环境与野生动物活动的随机性影响,极易出现检测中光流捕捉错误或简单语义难以识别的情况。针对此类问题,提出一种基于多帧关系网络特征增强的视频目标检测方法(multi-relation video object detection,MR-VOD)。该算法在图像关系网络的基础上,综合考虑上下帧目标之间的关系,通过多阶段推理,实现对野生动物目标的准确检测。同时,以神农架林区野生动物红外相机视频为基础,构建相关野生动物视频目标检测数据样本集作为实验区。试验证明,改进后的算法检测性能有所提升,平均准确率达81.96%,比Faster R-CNN提高9.32个百分点,在川金丝猴(Rhinopithecus roxellana)的检测上提升30.79个百分点,并在多种复杂场景下测试表现良好,有效减少了错检漏检的情况。该算法的实现将为神农架野生动物智能监测云平台提供检测基础,同时为后续开展的野生动物保护、种群评估提供必要的技术支撑。 展开更多
关键词 关系网络 视频目标检测 野生动物 复杂环境 特征增强
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地方政府协作治理的网络结构及行动路径研究--以新安江流域为例 被引量:1
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作者 崔晶 裘文韬 《内蒙古社会科学》 北大核心 2025年第1期57-64,F0003,共9页
区域协作治理能够跨越传统行政界线提供区域公共产品、应对区域公共问题,是推进美丽中国建设、健全生态环境治理体系的重要机制。作为全国首个跨省流域生态补偿机制试点地区,新安江流域成为研究地方政府协作治理的一个典型样本。在对新... 区域协作治理能够跨越传统行政界线提供区域公共产品、应对区域公共问题,是推进美丽中国建设、健全生态环境治理体系的重要机制。作为全国首个跨省流域生态补偿机制试点地区,新安江流域成为研究地方政府协作治理的一个典型样本。在对新安江流域协作治理的发展历程进行梳理、对流域协作治理网络结构和行动路径展开机理分析的过程中发现,纵向干预是促成流域协作治理的首要推动力,但在纵向干预退出后,地方政府间的横向协作就会成为协作治理得以持续并完善的主要原因。在这一过程中,新安江流域协作治理的网络结构从领导网络组织(NLO)演变为受控型网络行政组织(RNAO),流域协作治理效果得到同步提升。与此同时,协作治理效果又反作用于政府间的互动和网络结构调整,协作治理行为与效果之间形成双向互动,流域协作治理的适应性、稳定性和持续性得到有效增强。鉴于此,有必要进一步推动流域协作治理,适时进行纵向干预、加强横向协作、促进多元主体参与。 展开更多
关键词 流域生态环境治理 地方政府协作 网络治理 新安江流域
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建成环境影响下的城市轨道交通客流多步短时预测 被引量:3
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作者 李之红 郄堃 +2 位作者 王健宇 许晗 陈金政 《交通运输系统工程与信息》 北大核心 2025年第1期160-172,共13页
为挖掘客流的复杂时空耦合关系,解析建成环境影响下的轨道交通客流出行规律,本文提出一种考虑城市建成环境的时空双层超图神经网络模型(Spatial Temporal-Double Hypergraph Neural Network,STDHGNN)。模型分为双层超图神经网络和时间... 为挖掘客流的复杂时空耦合关系,解析建成环境影响下的轨道交通客流出行规律,本文提出一种考虑城市建成环境的时空双层超图神经网络模型(Spatial Temporal-Double Hypergraph Neural Network,STDHGNN)。模型分为双层超图神经网络和时间序列模块,双层超图神经网络模块用于挖掘轨道交通线路站点间的高阶连通关系和相邻同类建成区域站点的集群关系,时间序列模块用于表征历史客流数据的时间依赖关系。同时,以建成环境和线路作为变量构造新的损失函数,旨在剖析建成环境的影响,提高模型的预测性能。最后,以武汉轨道交通数据为例开展实证研究。研究结果显示:考虑建成环境和轨道站点高阶连通关系对客流预测精度的提升效果显著,本模型均方根误差(RMSE)和平均绝对误差(MAE)值分别为52.04和29.32,比基线模型降低了22%以上,性能显著优于基线模型;通过消融实验验证了融合轨道高阶联通关系和建成环境对模型性能的贡献,其中,单步预测任务中,考虑这两种因素使模型性能分别提升了6%和9%,多步预测任务中,分别提升了4%和12%;构造的融合建成环境因素的可解释损失函数,提高了模型的预测性能,同时,使模型具备更好的科学性和可解释性。研究成果为城市轨道交通的客流管理和列车调度提供了技术支持。 展开更多
关键词 智能交通 客流多步预测 超图时空网络 城市轨道交通 建成环境影响 可解释损失函数
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基于特征相似性的机会网络链路预测
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作者 刘琳岚 唐家威 朱文俊 《工程科学与技术》 北大核心 2025年第2期12-21,共10页
机会网络是一种利用节点移动带来相遇机会实现通信的自组织网络,可应用于野生动物追踪、水下营救、偏远地区网络覆盖等场景。相较于普通网络,机会网络具有节点连接稀疏、网络结构复杂及拓扑变化频繁等特点,给机会网络带来挑战。本文提... 机会网络是一种利用节点移动带来相遇机会实现通信的自组织网络,可应用于野生动物追踪、水下营救、偏远地区网络覆盖等场景。相较于普通网络,机会网络具有节点连接稀疏、网络结构复杂及拓扑变化频繁等特点,给机会网络带来挑战。本文提出一种基于特征相似性的机会网络链路预测模型(FS-ET)。首先,采用Graph2vec模型表征网络得到其样本熵和模型训练时长,基于二者选取合适的切片时长,将动态网络进行切片生成离散的网络演化序列。然后,采用基于GraphSAGE的节点嵌入模型提取节点潜在特征,并结合节点的连接时长计算节点对的潜在特征相似性;通过分析节点与多阶邻居的连边关系,根据节点局部连接信息计算节点对的拓扑结构相似性;采用L2范数对潜在特征相似性及拓扑结构相似性进行融合。最后,改进趋势移动平均法对历史信息进行时序特征提取,并提取融合后节点相似性的时序特征,得到未来节点间产生连接的可能性。在ITC、MIT、Infocom05和Infocom06共4个真实机会网络数据集上进行了切片、模型复杂度、泛化性、有效性的实验。结果表明:与长短期记忆网络模型(LSTM)、网络嵌入补充网络域中相似性模型(NESND)、端到端链路预测模型(E-LSTM-D)、非线性链路预测模型(GCN-GAN)、结构嵌入门控循环单元的预测模型(SE-GRU)、一种新的端到端链路预测模型(GC-LSTM)等相比,本文提出的FS-ET模型提升了0.5%~24.8%的AUC和1.07%~22.77%的F1-score,相较于其他基线模型均有一定程度的提升,验证了本文模型具有良好的预测性能。 展开更多
关键词 机会网络 链路预测 节点嵌入 节点潜在特征相似性 节点拓扑结构相似性
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云计算环境下多模态异构网络数据安全存储方法 被引量:1
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作者 李晓静 杨秀杰 《现代电子技术》 北大核心 2025年第6期63-67,共5页
为了快速、准确地存储多模态异构网络数据,提出一种云计算环境下多模态异构网络数据安全存储方法。采用编译套件部署多模态异构网络,利用后端编译模组生成网络的初始化配置,再利用前端编译模组分析与优化网络。针对多模态异构网络,构建... 为了快速、准确地存储多模态异构网络数据,提出一种云计算环境下多模态异构网络数据安全存储方法。采用编译套件部署多模态异构网络,利用后端编译模组生成网络的初始化配置,再利用前端编译模组分析与优化网络。针对多模态异构网络,构建包括客户端、服务器端、云存储服务插件、元数据存储的私有云存储架构。私有云存储架构采用虚拟化加解密方式,运行基于匿名广播加密的数据加密算法,引入拉格朗日插值方法,利用数据对应的会话密钥实现多模态异构网络数据的安全存储。实验结果表明,所提方法能够高效地存储多模态异构网络数据,数据传输的吞吐量高于3 Mb/s,加解密耗时低,存储的完整性高。 展开更多
关键词 云计算环境 多模态 异构网络 数据安全 存储方法 匿名广播加密 云存储架构
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长大隧道对牵引网电气参数及供电性能的影响
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作者 吴命利 曹国涛 +1 位作者 叶晶晶 胡亮 《铁道工程学报》 北大核心 2025年第7期77-82,共6页
研究目的:长大隧道环境的地层结构与平面大地区段差异显著,可能导致牵引网电气参数和供电性能发生变化。因此,亟需探究长大隧道环境下牵引网电气参数及供电性能的变化特性。本文通过实地测试,获得了长大隧道环境下牵引网电气参数值,对... 研究目的:长大隧道环境的地层结构与平面大地区段差异显著,可能导致牵引网电气参数和供电性能发生变化。因此,亟需探究长大隧道环境下牵引网电气参数及供电性能的变化特性。本文通过实地测试,获得了长大隧道环境下牵引网电气参数值,对比分析了理论值和实测值的差异。最后,通过MATLAB/Simulink验证了长大隧道环境对空载容升特性、压损特性、阻抗频率特性的影响。研究结论:(1)基于简化Carson公式和Tylavsky公式的理论计算无法准确计算隧道结构中复杂的回流系统,二者理论计算值均略大于实际测量值;(2)长大隧道内牵引网受吊柱腕臂影响,对地电容显著增大且远大于理论计算值,实际计算时不可忽略;(3)在同种供电方式下,长大隧道环境下牵引网电抗值小于开放路基区段,分布电容值大于开放路基区,导致牵引网电压较高;(4)长大隧道环境影响牵引网分布电容值,导致牵引网谐振频率点左移;(5)本研究对电气化铁路牵引网电气参数理论计算和仿真分析具有指导和借鉴意义。 展开更多
关键词 隧道环境 牵引网 电气参数 供电性能 现场测试
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基于城市规划布局的绿地系统“冷岛网络”建构及应用——以重庆市高新区绿地专项规划为例
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作者 王立 邬铃莉 +2 位作者 王怀 韩贵锋 李平 《西部人居环境学刊》 北大核心 2025年第3期85-93,共9页
绿地“冷岛效应”对于改善城市热环境具有重要意义。为通过优化绿地布局提升绿地系统冷岛效应,文章以高新区绿地系统规划为例,在规划语境下以“规模”为核心变量建立冷岛范围预测模型,结果表明两者呈反正切函数关系;结合复杂网络方法,... 绿地“冷岛效应”对于改善城市热环境具有重要意义。为通过优化绿地布局提升绿地系统冷岛效应,文章以高新区绿地系统规划为例,在规划语境下以“规模”为核心变量建立冷岛范围预测模型,结果表明两者呈反正切函数关系;结合复杂网络方法,探索形成以绿地斑块为“节点”、以斑块间冷岛范围在空间上的重叠关系为“边”的冷岛网络建构路径;从系统、子群、个体三个维度分析高新区冷岛网络特征发现,其冷岛网络整体集聚性差、3大子群的节点连通效率差异显著、系统内除寨山坪节点外缺少高中心度节点;将“冷岛网络”与研究区现状热环境叠加识别出降温“盲区”,并以强化系统整体冷岛效应为导向,提出打造区域结构绿网、织补绿网降温盲区、调控绿地空间形态的绿地系统布局优化策略。研究结果可为城市绿地系统规划以及相关标准制定提供参考依据。 展开更多
关键词 绿地系统 冷岛网络 复杂网络分析 热环境 布局优化策略。
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基于AI的噪声环境下远距离高清音频采集研究 被引量:1
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作者 黄丽娜 《现代电子技术》 北大核心 2025年第4期130-134,共5页
为提升远距离采集音频信号的强度,深度滤除音频信号噪声以提取有用音频部分,提出一种基于AI的噪声环境下远距离高清音频采集方法。构建远距离高清音频采集结构,分别通过模拟增益和数字增益技术进行音频信号增益处理,以提升音频信号强度... 为提升远距离采集音频信号的强度,深度滤除音频信号噪声以提取有用音频部分,提出一种基于AI的噪声环境下远距离高清音频采集方法。构建远距离高清音频采集结构,分别通过模拟增益和数字增益技术进行音频信号增益处理,以提升音频信号强度。依据短时傅里叶变换提取音频增益信号频域特征,输入到长短期记忆网络中,实现音频信号深度噪声去除,得到高清音频频域信息;再通过短时傅里叶逆变换处理该信号,实现音频信号重构,最终达到噪声环境下远距离高清音频采集的目的。实验验证结果表明:依据音频信号增益能够有效提升采集音频信号的强度,并避免信号受距离、噪声影响而逐渐衰减,继而有效滤除音频信号噪声数据,提取其中有用的音频信号,确保音频信号高清度;且最终采集音频信号信噪比均高于18 dB,可懂度均高于97%,有效验证了所提方法的有效性和准确性。 展开更多
关键词 高清音频采集 AI 噪声环境 信号强度 远距离 长短期记忆网络 短时傅里叶变换
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