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A novel similarity measure for mining missing links in long-path networks 被引量:1
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作者 Yijun Ran Tianyu Liu +1 位作者 Tao Jia Xiao-Ke Xu 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第6期56-64,共9页
Network information mining is the study of the network topology,which may answer a large number of applicationbased questions towards the structural evolution and the function of a real system.The question can be rela... Network information mining is the study of the network topology,which may answer a large number of applicationbased questions towards the structural evolution and the function of a real system.The question can be related to how the real system evolves or how individuals interact with each other in social networks.Although the evolution of the real system may seem to be found regularly,capturing patterns on the whole process of evolution is not trivial.Link prediction is one of the most important technologies in network information mining,which can help us understand the evolution mechanism of real-life network.Link prediction aims to uncover missing links or quantify the likelihood of the emergence of nonexistent links from known network structures.Currently,widely existing methods of link prediction almost focus on short-path networks that usually have a myriad of close triangular structures.However,these algorithms on highly sparse or longpath networks have poor performance.Here,we propose a new index that is associated with the principles of structural equivalence and shortest path length(SESPL)to estimate the likelihood of link existence in long-path networks.Through a test of 548 real networks,we find that SESPL is more effective and efficient than other similarity-based predictors in long-path networks.Meanwhile,we also exploit the performance of SESPL predictor and of embedding-based approaches via machine learning techniques.The results show that the performance of SESPL can achieve a gain of 44.09%over GraphWave and 7.93%over Node2vec.Finally,according to the matrix of maximal information coefficient(MIC)between all the similarity-based predictors,SESPL is a new independent feature in the space of traditional similarity features. 展开更多
关键词 structural equivalence shortest path length long-path networks missing links
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Semantic-aware graph convolution network on multi-hop paths for link prediction 被引量:1
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作者 彭斐 CHEN Shudong +2 位作者 QI Donglin YU Yong TONG Da 《High Technology Letters》 EI CAS 2023年第3期269-278,共10页
Knowledge graph(KG) link prediction aims to address the problem of missing multiple valid triples in KGs. Existing approaches either struggle to efficiently model the message passing process of multi-hop paths or lack... Knowledge graph(KG) link prediction aims to address the problem of missing multiple valid triples in KGs. Existing approaches either struggle to efficiently model the message passing process of multi-hop paths or lack transparency of model prediction principles. In this paper,a new graph convolutional network path semantic-aware graph convolution network(PSGCN) is proposed to achieve modeling the semantic information of multi-hop paths. PSGCN first uses a random walk strategy to obtain all-hop paths in KGs,then captures the semantics of the paths by Word2Sec and long shortterm memory(LSTM) models,and finally converts them into a potential representation for the graph convolution network(GCN) messaging process. PSGCN combines path-based inference methods and graph neural networks to achieve better interpretability and scalability. In addition,to ensure the robustness of the model,the value of the path thresholdKis experimented on the FB15K-237 and WN18RR datasets,and the final results prove the effectiveness of the model. 展开更多
关键词 knowledge graph(KG) link prediction graph convolution network(GCN) knowledge graph completion(KGC) multi-hop paths semantic information
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Using Link Analysis Technique with a Modified Shortest-Path Algorithm to Fight Money Laundering
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作者 CHEN Yunkai MAI Quanwe LU Zhengding 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1352-1356,共5页
Effective link analysis techniques are needed to help law enforcement and intelligence agencies fight money laundering. This paper presents a link analysis technique that uses a modified shortest-path algorithms to id... Effective link analysis techniques are needed to help law enforcement and intelligence agencies fight money laundering. This paper presents a link analysis technique that uses a modified shortest-path algorithms to identify the strongest association paths between entities in a money laundering network. Based on two-tree Dijkstra and Priority'First-Search (PFS) algorithm, a modified algorithm is presented. To apply the algorithm, a network representation transformation is made first. 展开更多
关键词 link analysis shortest-path algorithm fight money laundering
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Interactive Heuristic D* Path Planning Solution Based on PSO for Two-Link Robotic Arm in Dynamic Environment
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作者 Firas A. Raheem Umniah I. Hameed 《World Journal of Engineering and Technology》 2019年第1期80-99,共20页
This paper is devoted to find an intelligent and safe path for two-link robotic arm in dynamic environment. This paper focuses on computational part of motion planning in completely changing dynamic environment at eve... This paper is devoted to find an intelligent and safe path for two-link robotic arm in dynamic environment. This paper focuses on computational part of motion planning in completely changing dynamic environment at every motion sample domains,?since the local minima and sharp edges are the most common problems in all path planning algorithms. In addition, finding a path solution in a dynamic environment represents a challenge for the robotics researchers,?so in this paper, a proposed mixing approach was suggested to overcome all these obstructions. The proposed approach methodology?for obtaining robot interactive path planning solution in known dynamic environment utilizes?the use of modified heuristic D-star (D*) algorithm based on the full free Cartesian space analysis at each motion sample with the Particle Swarm Optimization (PSO) technique.?Also, a modification on the?D* algorithm has been done to match the dynamic environment requirements by adding stop and return backward cases which is not included in the original D* algorithm theory. The resultant interactive path solution was computed by taking into consideration the time and position changes of the moving obstacles. Furthermore, to insure the enhancement of the?final path length optimality, the PSO technique was used.?The simulation results are given to show the effectiveness of the proposed method. 展开更多
关键词 D* Algorithm Particle SWARM Optimization (PSO) path Planning TWO-link Arm KNOWN Dynamic Environment
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Link prediction based on a semi-local similarity index 被引量:13
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作者 白萌 胡柯 唐翌 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期498-504,共7页
Missing link prediction provides significant instruction for both analysis of network structure and mining of unknown links in incomplete networks. Recently, many algorithms have been proposed based on various node-si... Missing link prediction provides significant instruction for both analysis of network structure and mining of unknown links in incomplete networks. Recently, many algorithms have been proposed based on various node-similarity measures. Among these measures, the common neighbour index, the resource allocation index, and the local path index, stemming from different source, have been proved to have relatively high accuracy and low computational effort. In this paper, we propose a similarity index by combining the resource allocation index and the local path index. Simulation results on six unweighted networks show that the accuracy of the proposed index is higher than that of the local path one. Based on the same idea of the present index, we develop its corresponding weighted version and test it on several weighted networks. It is found that, except for the USAir network, the weighted variant also performs better than both the weighted resource allocation index and the weighted local path index. Due to the improved accuracy and the still low computational complexity, the indices may be useful for link prediction. 展开更多
关键词 link prediction resource allocation local path
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Link Budget Design for RF Line-of-Sight via Theoretical Propagation Prediction 被引量:1
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作者 Anwar H. Ibrahim Mohammed F. Alsharekh +2 位作者 Mohammed S. Almanee Abdulrahman S. Al-Turki Muhammed Islam 《International Journal of Communications, Network and System Sciences》 2019年第1期11-17,共7页
Line-of-sight (LOS) link planning condition has been observed to have effects on the atmospheric factor which cause crucial signal loss. The main objective of the planning was to improve a set of a link using point to... Line-of-sight (LOS) link planning condition has been observed to have effects on the atmospheric factor which cause crucial signal loss. The main objective of the planning was to improve a set of a link using point to point condition to assist the performance in emerging its strategy for handling the fixed WLAN service. The purpose of this paper is to provide a quick description of various propagation loss mechanisms on Link Budget Tool (LBT). LBT is customized to create point to point link for local area network (LAN) through radio frequency range operating between 2.400 GHz and 5.800 GHz. This software is able to define the effect of signal loss and expected performances according to the distances between link propagation conditions based on a number of system parameters. 展开更多
关键词 path Loss (PL) Line of SIGHT (LOS) Microwave link BUDGET (MLB) link Planning (LP)
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Semantic Path Attention Network Based on Heterogeneous Graphs for Natural Language to SQL Task 被引量:1
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作者 周浩冉 宋晖 龚蒙蒙 《Journal of Donghua University(English Edition)》 CAS 2023年第5期531-538,共8页
The natural language to SQL(NL2SQL)task is an emerging research area that aims to transform a natural language with a given database into an SQL query.The earlier approaches were to process the input into a heterogene... The natural language to SQL(NL2SQL)task is an emerging research area that aims to transform a natural language with a given database into an SQL query.The earlier approaches were to process the input into a heterogeneous graph.However,previous models failed to distinguish the types of multi-hop connections of the heterogeneous graph,which tended to ignore crucial semantic path information.To this end,a two-layer attention network is presented to focus on essential neighbor nodes and mine enlightening semantic paths for feature encoding.The weighted edge is introduced for schema linking to connect the nodes with semantic similarity.In the decoding phase,a rule-based pruning strategy is offered to refine the generated SQL queries.From the experimental results,the approach is shown to learn a good encoding representation and decode the representation to generate results with practical meaning. 展开更多
关键词 semantic path two-layer attention network semantic linking
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New SRLG-diverse path selection algorithm in survivable GMPLS networks
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作者 Wang Yan Zheng Junhui Zeng Jiazhi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期412-419,共8页
In conventional shared risk link group (SRLG)-diverse path selection (CSPS) algorithm in survivable GMPLS networks, SRLG is taken into account when selecting the backup paths, while the primary path selection meth... In conventional shared risk link group (SRLG)-diverse path selection (CSPS) algorithm in survivable GMPLS networks, SRLG is taken into account when selecting the backup paths, while the primary path selection method is the sarne as the algorithms without SRLG constraint. A problem of CSPS algorithm is that, after a primary path is selected, the success probability to select an SRLG-diverse backup path for it is low. If SRLG is taken into account when computing the primary path, then the probability to successfully select an SRLG-diverse backup path will be much increased. Based on this idea, an active SRLG-diverse path selection (ASPS) algorithm is proposed. To actively avoid selecting those SRLG links, when computing the primary path, a link that share risk with more links is assigned a larger link cost. To improve the resource utilization ratio, it is permitted that the bandwidth resources are shared among backup paths. What is more, differentiated reliability (DiR) requirements of different customers are considered in ASPS algorithm. The simulation results show that, compared with CSPS algorithm, ASPS algorithm not only increases successful protection probability but also improves resource utilization ratio. 展开更多
关键词 generaliged multiprotocol label switching shared risk link group path selection SURVIVABILITY
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基于专利引文网络的类器官领域技术主路径分析 被引量:2
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作者 张婷 陈娟 +2 位作者 卢岩 徐东紫 欧阳昭连 《中国新药杂志》 北大核心 2025年第7期684-692,共9页
目的:基于专利引文网络探索类器官领域的技术发展主路径。方法:本研究通过构建类器官领域的专利引文网络,采用搜索路径连接数算法(search path link count,SPLC)计算遍历权重,对类器官领域开展主路径分析,探索该领域的技术发展轨迹。结... 目的:基于专利引文网络探索类器官领域的技术发展主路径。方法:本研究通过构建类器官领域的专利引文网络,采用搜索路径连接数算法(search path link count,SPLC)计算遍历权重,对类器官领域开展主路径分析,探索该领域的技术发展轨迹。结果:类器官领域共有专利申请2 250项,包含专利引文12 722件;专利申请数量逐年增长,技术开发聚焦于疾病模型、药物筛选、细胞培养及器官芯片等方向。主路径分析显示,全局主路径上专利数量最多,有12件,包含1条技术路线,全局关键路径主路径与全局主路径一致;局部前向主路径上有10件专利,包含1条技术路线;这2条技术路线反映出中国类器官领域的技术发展轨迹,中国技术创新聚焦于基于肿瘤类器官技术的疾病机制研究、基于肺癌类器官模型的疾病机制研究、肺癌类器官模型的开发与优化。局部后向主路径上有9件专利,包含2条技术路线,局部关键路径主路径与局部后向主路径一致;这2条技术路线反映出美国类器官领域的技术发展轨迹,技术创新聚焦于胃肠道类器官培养与疾病模型研究、干细胞驱动的器官功能修复技术、细胞移植与器官再生。结论:本研究通过类器官领域的专利主路径分析,识别技术发展轨迹,从情报学角度为类器官研发提供信息支撑。 展开更多
关键词 类器官 专利引文网络 主路径分析 搜索路径连接数算法
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Research on the Weak Links and Solutions in the Education of College Student Party Members
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作者 JIA Yuhua 《外文科技期刊数据库(文摘版)教育科学》 2021年第8期086-089,共6页
The education and management of party members is the basic and regular work of the party building, which is crucial to improving the quality of the party members and maintaining the advanced nature and purity of the p... The education and management of party members is the basic and regular work of the party building, which is crucial to improving the quality of the party members and maintaining the advanced nature and purity of the party members. College student Party members are an important part of Party members, and it is of great significance to do a good job in educating college student Party members. Based on the exploration of the weak links in the education process of college student party members, this paper puts forward targeted solutions to improve the pertinence and effectiveness of college student party members education. 展开更多
关键词 colleges and universities party member education weak links the path
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脑机接口领域的专利主路径分析
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作者 张婷 徐东紫 +5 位作者 陈娟 卢岩 严舒 潘黎姿 王建波 欧阳昭连 《中国医疗设备》 2025年第3期8-15,21,共9页
目的通过对脑机接口领域的专利引文网络分析探讨技术发展主路径。方法构建脑机接口领域的专利引文网络,采用搜索路径连接数计算遍历权重,采用全局搜索与局部搜索2种路径搜索方式对该领域的全局主路径、全局关键路径主路径、局部前向主... 目的通过对脑机接口领域的专利引文网络分析探讨技术发展主路径。方法构建脑机接口领域的专利引文网络,采用搜索路径连接数计算遍历权重,采用全局搜索与局部搜索2种路径搜索方式对该领域的全局主路径、全局关键路径主路径、局部前向主路径、局部后向主路径及局部关键路径主路径进行分析,探索该领域的技术发展轨迹。结果脑机接口领域共有专利申请15519项,包含专利引文140691件,专利申请数量逐年增长。技术开发聚焦于神经刺激与调控技术、神经信号采集与处理技术、脑机接口硬件技术等方向。主路径分析显示,技术主题以电刺激为核心,强调精准的神经调控与个性化治疗。全局主路径上专利数量最多(16件),包含2条技术路线,全局关键路径主路径与全局主路径一致;局部前向主路径上有14件专利,包含1条技术路线,局部关键路径主路径与局部前向主路径一致;局部后向主路径上有10件专利,包含1条技术路线。结论本研究通过脑机接口领域的专利主路径分析,识别技术发展轨迹,从情报学角度为脑机接口领域研发提供信息支撑。 展开更多
关键词 脑机接口 主路径分析 专利分析 专利引文网络 搜索路径连接数算法
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红色文化与大学生社会主义核心价值观“菜单化”教育的理论链接与路径选择
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作者 仇桂且 李环宇 《淮阴工学院学报》 2025年第1期79-85,共7页
红色文化是中国共产党带领广大人民群众在长期革命建设实践中创造和培育的先进文化成果。红色文化作为社会主义先进文化与社会主义核心价值观一脉相承,蕴含着丰富的爱国主义情感和奋斗精神,具有显著的历史性、革命性和教育性。在新的历... 红色文化是中国共产党带领广大人民群众在长期革命建设实践中创造和培育的先进文化成果。红色文化作为社会主义先进文化与社会主义核心价值观一脉相承,蕴含着丰富的爱国主义情感和奋斗精神,具有显著的历史性、革命性和教育性。在新的历史时期,深入把握红色文化与社会主义核心价值观之间的理论逻辑,统筹谋划、系统推进大学生社会主义核心价值观教育,通过社会主义核心价值观“菜单化”教育模式的探索,可不断增强社会主义核心价值观对大学生的吸引力、凝聚力和影响力,提升大学生社会主义核心价值观教育的实效性。 展开更多
关键词 社会主义核心价值观 “菜单化”教育 理论链接 路径选择
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融合有向关系与关系路径的层次注意力的知识图谱补全 被引量:1
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作者 翟社平 杨晴 +1 位作者 黄妍 杨锐 《计算机应用》 北大核心 2025年第4期1148-1156,共9页
已有的知识图谱补全(KGC)方法大多未充分挖掘三元组结构中的关系路径,仅考虑了图结构信息;同时现有模型在实体聚合过程中着重考虑邻域信息,对关系的学习相对简单。针对以上问题,提出融合有向关系和关系路径的图注意力模型DRPGAT。首先,... 已有的知识图谱补全(KGC)方法大多未充分挖掘三元组结构中的关系路径,仅考虑了图结构信息;同时现有模型在实体聚合过程中着重考虑邻域信息,对关系的学习相对简单。针对以上问题,提出融合有向关系和关系路径的图注意力模型DRPGAT。首先,将常规三元组转换为有向关系三元组,并引入注意力机制对不同的有向关系赋予不同的权重,从而完成实体信息的聚合,同时,建立关系路径模型,通过将关系位置嵌入路径信息区分不同位置之间的关系,并过滤无关路径得到有用的路径信息;其次,使用注意力机制对路径信息进行深度学习,以实现关系的聚合;最后,将实体与关系送入解码器,训练得到最终的补全结果。在2个真实数据集上进行链接预测实验,以验证所提模型的有效性。实验结果表明,在FB15k-237数据集上,相较于基线模型中的最优结果,DRPGAT的平均排名(MR)降低了13,平均倒数排名(MRR)、Hits@1、Hits@3、Hits@10分别提高1.9、1.2、2.3和1.6个百分点;在WN18RR数据集上,DRPGAT的MR降低了125,MRR、Hits@1、Hits@3、Hits@10分别提高了1.1、0.4、1.2和0.6个百分点,显示了所提模型的有效性。 展开更多
关键词 知识图谱 知识图谱补全 关系路径推理 层次注意力 链接预测
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融合多步关系路径和实体描述信息的知识图谱表示学习模型
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作者 冯勇 徐涵琪 +2 位作者 贾永鑫 徐红艳 王嵘冰 《计算机应用》 北大核心 2025年第S1期19-23,共5页
传统的知识图谱表示学习模型主要聚焦于三元组内部的结构信息,而未能充分利用外部语义增强嵌入表征能力,如没有充分考虑实体间的多步关系路径信息以及不同路径的重要程度,且没有利用实体描述信息增强上下文感知能力。为提升知识图谱的... 传统的知识图谱表示学习模型主要聚焦于三元组内部的结构信息,而未能充分利用外部语义增强嵌入表征能力,如没有充分考虑实体间的多步关系路径信息以及不同路径的重要程度,且没有利用实体描述信息增强上下文感知能力。为提升知识图谱的应用效果,提出融合多步关系路径和实体描述信息的知识图谱表示学习(MPDRL)模型。首先,对两实体间的路径信息进行编码,并使用自注意力机制计算路径权重,从而获得关系路径信息的表示;其次,使用BERT(Bidirectional Encoder Representations from Transformers)模型对实体描述信息进行编码,并利用双向注意力机制计算实体描述信息嵌入与三元组关系嵌入之间的注意力权重,从而增强实体的语义信息;最后,将关系路径信息嵌入、实体描述信息嵌入和三元组结构嵌入融合起来进行训练。为评估模型性能,在公开数据集上针对所提模型和基准模型进行链接预测和三元组分类的实验。结果表明:在链接预测任务中,与融合关系路径与实体描述信息的知识图谱表示学习方法(PDRL)、多跳关系路径模型Att-ConvBiLSTM以及融合实体描述与关系路径信息的知识图谱嵌入模型TPKGE相比,所提模型在FB15k-237数据集上的Hit@10指标分别提高了5.7、2.9、2.5个百分点;在三元组分类任务上,所提模型在FB15k-237和WN18RR数据集上的准确率较最优基准模型PDRL分别提升了2.81和0.90个百分点。 展开更多
关键词 知识表示 关系路径 知识图谱 链接预测 文本描述
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基于链路状态感知的卫星网络多路路由优化策略
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作者 张乐 李雨昂 +2 位作者 阔永红 周雨晨 杨龙 《空军工程大学学报》 北大核心 2025年第4期58-67,共10页
针对低轨卫星网络传输带宽不足以支撑大数据转发、链路需要周期性断开的问题,设计了基于链路状态感知的卫星网络多路路由优化策略,对低轨卫星的动态拓扑结构以及星间链路状态进行了建模,构建了多路径选择的优化问题。为提高优化问题的... 针对低轨卫星网络传输带宽不足以支撑大数据转发、链路需要周期性断开的问题,设计了基于链路状态感知的卫星网络多路路由优化策略,对低轨卫星的动态拓扑结构以及星间链路状态进行了建模,构建了多路径选择的优化问题。为提高优化问题的求解效率,设计了基于状态监控与路径预测的多路径选择算法,算法使用时间片分割拓扑以规避拓扑的动态性,通过监测状态对星间链路进行筛选来降低复杂度,并根据星历信息对链路通断进行预测,避免链路中断造成的大规模丢包,在计算阶段综合考虑传输时延、传输带宽以及传输成功率等实时链路状态,根据负载变化选出最优的多条路径,增大卫星网络的吞吐量,降低传输时延。仿真结果表明,相较于传统的接触图路由算法(CGR)、基于最短路径优先算法(SPF)和等价多路径算法(ECMP),当负载为8 Gbps时,所提方案的传输时延比其他3种算法分别低16.9%、11.4%和7.1%,网络吞吐量比其他3种算法分别高34.4%、26.9%和15.6%,传输成功率分别比其他3种算法分别高15.3%、9.6%和5.6%。 展开更多
关键词 卫星网络 动态拓扑 链路状态感知 传输时延 多路路由 传输带宽
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基于结构关系与风险量化的连锁故障扩展关键环节辨识
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作者 罗辰昊 刘星 +3 位作者 姚秀丽 魏震波 罗紫航 范梓远 《电力系统自动化》 北大核心 2025年第18期83-96,共14页
随着电力系统规模持续扩大、结构日趋复杂,其发生连锁故障的风险随之增加。为提升系统风险防控能力、准确识别连锁故障关键环节并揭示各环节间耦合关系及相互作用,文中对连锁故障关键环节定义进行了扩展,引入关键传播关系与关键区域概念... 随着电力系统规模持续扩大、结构日趋复杂,其发生连锁故障的风险随之增加。为提升系统风险防控能力、准确识别连锁故障关键环节并揭示各环节间耦合关系及相互作用,文中对连锁故障关键环节定义进行了扩展,引入关键传播关系与关键区域概念,提出一种基于结构关系与风险量化的扩展关键环节辨识方法。首先,建立配合-过载型连锁故障事故链模型对故障态势与传播路径进行分析;其次,采用一种基于导率优化的局部扩展算法挖掘电网的模糊重叠动态社区结构,实现对电网核心区域与模糊区域的识别;再次,利用事故链集和分区结果构建具有时空特征的风险时空传播图,并采用多维故障影响的量化指标对扩展关键环节进行辨识;最后,在IEEE 39节点系统和IEEE 118节点系统中进行算例仿真。结果表明,所提方法能够有效辨识扩展关键环节,揭示连锁故障不同环节间的耦合关系与级联作用。 展开更多
关键词 关键环节 连锁故障 事故链 故障态势 传播途径 动态社区 风险量化
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考虑反馈补偿的五轴联动数控刀具切削加工平滑插补算法 被引量:1
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作者 彭宗和 户群艳 《现代工业经济和信息化》 2025年第1期100-102,共3页
为了提高切削加工轨迹的平滑性,设计了考虑反馈补偿的五轴联动数控刀具切削加工平滑插补算法。采用平滑插补的方式,根据反馈偏差角补偿值修正刀具切削路径,以确保切削轨迹的平滑性。应用该方法后,刀具的加速度在2.3~2.8 m/s2之间波动,... 为了提高切削加工轨迹的平滑性,设计了考虑反馈补偿的五轴联动数控刀具切削加工平滑插补算法。采用平滑插补的方式,根据反馈偏差角补偿值修正刀具切削路径,以确保切削轨迹的平滑性。应用该方法后,刀具的加速度在2.3~2.8 m/s2之间波动,说明该方法有效降低了切削加速度,使切削加工的轨迹更加平滑。 展开更多
关键词 五轴联动数控机床 刀具切削加工 切削路径 平滑插补 反馈补偿
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空间回转式供弹机械手动力学分析
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作者 王伟伟 解凤娟 +2 位作者 高景洲 徐凯 杨海文 《兵器装备工程学报》 北大核心 2025年第5期230-236,共7页
针对大口径火炮自动供输弹系统中供弹机械手的自动和高可靠运转的需求,设计了一种三连杆串联式空间回转式供弹机械手,基于D-H参数法建立运动学模型并进行了运动路径规划,在构建空间回转式供弹机械手动力学模型的基础上确定了系统动力源... 针对大口径火炮自动供输弹系统中供弹机械手的自动和高可靠运转的需求,设计了一种三连杆串联式空间回转式供弹机械手,基于D-H参数法建立运动学模型并进行了运动路径规划,在构建空间回转式供弹机械手动力学模型的基础上确定了系统动力源。对供弹机械手进行了仿真验证,验证了3倍载荷工况条件下关键部件的强度与刚度,对带弹、空载两类循环过程进行运动学仿真验证了运动可达性,对带弹、空载两类工作循环过程中对各关节的回转力矩变化进行分析验证了系统动力源设计的准确性。结果表明,空间回转式供弹机械手结构设计合理,运动学模型和动力学模型为空间回转式供弹机械手的设计提供了理论依据。 展开更多
关键词 供弹机械手 三连杆串联式 空间回转式 运动路径规划 运动可达性 动力源设计
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基于多源知识图谱的疾病潜在药物发现研究
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作者 陈星羽 侯跃芳 +3 位作者 赖书兰 梅佳月 李梓萌 韩玙蔓 《医学信息学杂志》 2025年第7期40-44,52,共6页
目的/意义构建多源知识图谱,提出基于知识图谱的药物发现方法,为疾病新药研发提供参考依据。方法/过程设计知识图谱架构,优选7种异构数据库,经知识抽取、数据处理与清洗、知识融合构建知识图谱。基于图谱和SemMedDB建立推理规则及关联路... 目的/意义构建多源知识图谱,提出基于知识图谱的药物发现方法,为疾病新药研发提供参考依据。方法/过程设计知识图谱架构,优选7种异构数据库,经知识抽取、数据处理与清洗、知识融合构建知识图谱。基于图谱和SemMedDB建立推理规则及关联路径,改进加权链路预测方法,提出可用于药物发现的综合知识发现方法。结果/结论以阿尔茨海默病为例,构建含67780个实体、282870个三元组的多源异构疾病知识图谱,预测潜在治疗药物184种。 展开更多
关键词 疾病知识图谱 药物发现 知识推理 路径发现 链路预测
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卫星网络拓扑可靠性分析:基于连通度与多径协同传输
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作者 李朕 虞志刚 +2 位作者 章扬 李果 郭涛 《无线电通信技术》 北大核心 2025年第4期713-723,共11页
卫星网络凭借广域覆盖、灵活组网、不受地面环境限制等优势,已成为6G研究的热点方向之一。与传统地面网络不同,卫星的高速运动导致星间的建立与维护面临诸多挑战。日凌现象、电离层闪烁及雨雪天气等复杂环境也会降低星间链路可靠性。与... 卫星网络凭借广域覆盖、灵活组网、不受地面环境限制等优势,已成为6G研究的热点方向之一。与传统地面网络不同,卫星的高速运动导致星间的建立与维护面临诸多挑战。日凌现象、电离层闪烁及雨雪天气等复杂环境也会降低星间链路可靠性。与此同时,以激光为代表的高速星间链路技术目前仍处起步阶段,成熟度仍有待提高。这些因素都可能导致星间链路的故障,进而影响卫星网络的整体性能。因此,亟需探究星间链路故障对卫星网络可靠性的影响。分析了卫星网络规模对网络可靠性的影响,给出不同网络规模下星间链路故障率建议低于的阈值边界。讨论了卫星网络拓扑构型对网络可靠性的影响,给出网络连通性以及平均跳数随拓扑结构的变化关系。研究了多路径传输对网络可靠性的影响,基于门杰引理讨论了连通度随星间链路故障率的变化关系,仿真结果显示多路径并行传输方案能够将信息成功传输概率从76%提升至99%,以期为未来网络拓扑优化与可靠性提升提供有益的参考。 展开更多
关键词 卫星网络 星间链路 连通度 可靠性 多径协同传输
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