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Interpreting Randomly Wired Graph Models for Chinese NER
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作者 Jie Chen Jiabao Xu +2 位作者 Xuefeng Xi Zhiming Cui Victor S.Sheng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第1期747-761,共15页
Interpreting deep neural networks is of great importance to understand and verify deep models for natural language processing(NLP)tasks.However,most existing approaches only focus on improving the performance of model... Interpreting deep neural networks is of great importance to understand and verify deep models for natural language processing(NLP)tasks.However,most existing approaches only focus on improving the performance of models but ignore their interpretability.In this work,we propose a Randomly Wired Graph Neural Network(RWGNN)by using graph to model the structure of Neural Network,which could solve two major problems(word-boundary ambiguity and polysemy)of ChineseNER.Besides,we develop a pipeline to explain the RWGNNby using Saliency Map and Adversarial Attacks.Experimental results demonstrate that our approach can identify meaningful and reasonable interpretations for hidden states of RWGNN. 展开更多
关键词 Named entity recognition graph neural network saliency map random graph network INTERPRETATION
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Markov Chains Based on Random Generalized 1-Flipper Operations for Connected Regular Multi-digraphs
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作者 邓爱平 伍陈晨 +1 位作者 王枫杰 胡宇庭 《Journal of Donghua University(English Edition)》 CAS 2023年第1期110-115,共6页
The properties of generalized flip Markov chains on connected regular digraphs are discussed.The 1-Flipper operation on Markov chains for undirected graphs is generalized to that for multi-digraphs.The generalized 1-F... The properties of generalized flip Markov chains on connected regular digraphs are discussed.The 1-Flipper operation on Markov chains for undirected graphs is generalized to that for multi-digraphs.The generalized 1-Flipper operation preserves the regularity and weak connectivity of multi-digraphs.The generalized 1-Flipper operation is proved to be symmetric.Moreover,it is presented that a series of random generalized 1-Flipper operations eventually lead to a uniform probability distribution over all connected d-regular multi-digraphs without loops. 展开更多
关键词 random graph transformation regular multi-digraph Markov chain 1-Flipper triangle reverse
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A novel configuration model for random graphs with given degree sequence 被引量:1
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作者 徐新平 刘峰 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期282-286,共5页
Recently, random graphs in which vertices are characterized by hidden variables controlling the establishment of edges between pairs of vertices have attracted much attention. This paper presents a specific realizatio... Recently, random graphs in which vertices are characterized by hidden variables controlling the establishment of edges between pairs of vertices have attracted much attention. This paper presents a specific realization of a class of random network models in which the connection probability between two vertices (i, j) is a specific function of degrees ki and kj. In the framework of the configuration model of random graphsp we find the analytical expressions for the degree correlation and clustering as a function of the variance of the desired degree distribution. The obtained expressions are checked by means of numerical simulations. Possible applications of our model are discussed. 展开更多
关键词 random graphs configuration model CORRELATIONS
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MINIMUM CONGESTION SPANNING TREES IN BIPARTITE AND RANDOM GRAPHS 被引量:1
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作者 M.I. Ostrovskii 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期634-640,共7页
The first problem considered in this article reads: is it possible to find upper estimates for the spanning tree congestion in bipartite graphs, which are better than those for general graphs? It is proved that ther... The first problem considered in this article reads: is it possible to find upper estimates for the spanning tree congestion in bipartite graphs, which are better than those for general graphs? It is proved that there exists a bipartite version of the known graph with spanning tree congestion of order n3/2, where n is the number of vertices. The second problem is to estimate spanning tree congestion of random graphs. It is proved that the standard model of random graphs cannot be used to find graphs whose spanning tree congestion has order greater than n3/2. 展开更多
关键词 Bipartite graph random graph minimum congestion spanning tree
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THE STATIONARY DISTRIBUTION OF A CONTINUOUS-TIME RANDOM GRAPH PROCESS WITH INTERACTING EDGES 被引量:1
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作者 韩东 《Acta Mathematica Scientia》 SCIE CSCD 1994年第S1期98-102,共5页
In previous papers, the stationary distributions of a class of discrete and continuoustime random graph processes with state space consisting of the simple and directed graphs on Nvenices were studied. In this paper, ... In previous papers, the stationary distributions of a class of discrete and continuoustime random graph processes with state space consisting of the simple and directed graphs on Nvenices were studied. In this paper, the random graph graph process is extended one impotent stepfurther by allowing interaction of edges. Similarly, We obtha the expressions of the stationarydistributions and prove that the process is ergodic under different editions. 展开更多
关键词 random graph prooes Minimum Q-process Stationary distribution Ergodicity.
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THE REGULARITY OF RANDOM GRAPH DIRECTED SELF-SIMILAR SETS 被引量:2
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作者 ZhangXiaoqun LiuYanyan 《Acta Mathematica Scientia》 SCIE CSCD 2004年第3期485-492,共8页
A set in Rd is called regular if its Hausdorff dimension coincides with its upper box counting dimension. It is proved that a random graph-directed self-similar set is regular a.e..
关键词 random graph-directed self-similar set Hausdorff dimension box-counting dimension REGULAR
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Continuous-Time Classical and Quantum Random Walk on Direct Product of Cayley Graphs
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作者 S. Salimi M.A. Jafarizadeh 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第6期1003-1009,共7页
In this paper we define direct product of graphs and give a recipe for obtaining probability of observing particle on vertices in the continuous-time classical and quantum random walk. In the recipe, the probability o... In this paper we define direct product of graphs and give a recipe for obtaining probability of observing particle on vertices in the continuous-time classical and quantum random walk. In the recipe, the probability of observing particle on direct product of graph is obtained by multiplication of probability on the corresponding to sub-graphs, where this method is useful to determining probability of walk on compficated graphs. Using this method, we calculate the probability of Continuous-time classical and quantum random walks on many of finite direct product Cayley graphs (complete cycle, complete Kn, charter and n-cube). Also, we inquire that the classical state the stationary uniform distribution is reached as t→∞ but for quantum state is not always satisfied. 展开更多
关键词 continuous-time random walk classical random walk quantum random walk direct product of graphs Cayley graphs
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Improved Approximation of Layout Problems on Random Graphs
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作者 Kevin K. H. Cheung Patrick Girardet 《Open Journal of Discrete Mathematics》 2020年第1期13-30,共18页
Inspired by previous work of Diaz, Petit, Serna, and Trevisan (Approximating layout problems on random graphs, Discrete Mathematics, 235, 2001, 245-253), we show that several well-known graph layout problems are appro... Inspired by previous work of Diaz, Petit, Serna, and Trevisan (Approximating layout problems on random graphs, Discrete Mathematics, 235, 2001, 245-253), we show that several well-known graph layout problems are approximable to within a factor arbitrarily close to 1 of the optimal with high probability for random graphs drawn from an Erd&#246;s-Renyi distribution with appropriate sparsity conditions using only elementary probabilistic analysis. Moreover, we show that the same results hold for the analogous problems on directed acyclic graphs. 展开更多
关键词 graph ARRANGEMENTS random graphS APPROXIMATION Algorithms Undirected graphS Directed ACYCLIC graphS
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Average flooding distance for MANETs in random graph models with spatial reuse
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作者 胡细 王汉兴 赵飞 《Journal of Shanghai University(English Edition)》 CAS 2007年第4期336-339,共4页
The flooding distance is an important parameter in the design and evaluation of a routing protocol, which is related not only to the delay time in the route discovery, but also to the stability and reliability of the ... The flooding distance is an important parameter in the design and evaluation of a routing protocol, which is related not only to the delay time in the route discovery, but also to the stability and reliability of the route. In this paper, the average flooding distance (AFD) for a mobile ad hoc network (MANET) in a random graph model was given based on the dynamic source routing (DSR) protocol. The influence of spatial reuse on the AFD was also studied. Compared with that in the model without the spatial reuse, the AFD in the model with the spatial reuse has much smaller value, when the connetivity probability between nodes in the network is small and when the number of reused times is large. This means that the route discovery with the spatial reuse is much more effective. 展开更多
关键词 mobile ad hoc network (MANET) dynamic source routing (DSR) random graph
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Influence of Inhomogeneity on Critical Behavior of Earthquake Model on Random Graph
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作者 ZHANG Duan-Ming SUN Fan YU Bo-Ming PAN Gui-Jun YIN Yah-Ping LI Rui SU Xiang-Ying 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期261-264,共4页
We consider the earthquake model on a random graph. A detailed analysis of the probability distribution of the size of the avalanches will be given. The model with different inhomogeneities is studied in order to comp... We consider the earthquake model on a random graph. A detailed analysis of the probability distribution of the size of the avalanches will be given. The model with different inhomogeneities is studied in order to compare the critical behavior of different systems. The results indicate that with the increase of the inhomogeneities, the avalanche exponents reduce, i.e., the different numbers of defects cause different critical behaviors of the system. This is virtually ascribed to the dynamical perturbation. 展开更多
关键词 self-organized criticality earthquake model critical behavior power-law finite size scaling random network
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On Origin of Power-Law Distributions in Self-Organized Criticality from Random Walk Treatment
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作者 CAO Xiao-Feng DENG Zong-Wei YANG Chun-Bin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期249-251,共3页
The origin of power-law distributions in self-organized criticality is investigated by treating the variation of the number of active sites in the system as a stochastic process. An avalanche is then regarded as a fir... The origin of power-law distributions in self-organized criticality is investigated by treating the variation of the number of active sites in the system as a stochastic process. An avalanche is then regarded as a first-return random walk process in a one-dimensional lattice. We assume that the variation of the number of active sites has three possibilities in each update: to increase by 1 with probability f1, to decrease by 1 with probability f2, or remain unchanged with probability 1 - f1 - f2. This mimics the dynamics in the system. Power-law distributions of the lifetime are found when the random walk is unbiased with equal probability to move in opposite directions. This shows that power-law distributions in self-organized criticality may be caused by the balance of competitive interactions. 展开更多
关键词 power-law distribution sell'organized criticality random walk
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Heavy-Tailed Distributions Generated by Randomly Sampled Gaussian, Exponential and Power-Law Functions
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作者 Frederic von Wegner 《Applied Mathematics》 2014年第13期2050-2056,共7页
A simple stochastic mechanism that produces exact and approximate power-law distributions is presented. The model considers radially symmetric Gaussian, exponential and power-law functions inn= 1, 2, 3 dimensions. Ran... A simple stochastic mechanism that produces exact and approximate power-law distributions is presented. The model considers radially symmetric Gaussian, exponential and power-law functions inn= 1, 2, 3 dimensions. Randomly sampling these functions with a radially uniform sampling scheme produces heavy-tailed distributions. For two-dimensional Gaussians and one-dimensional exponential functions, exact power-laws with exponent –1 are obtained. In other cases, densities with an approximate power-law behaviour close to the origin arise. These densities are analyzed using Padé approximants in order to show the approximate power-law behaviour. If the sampled function itself follows a power-law with exponent –α, random sampling leads to densities that also follow an exact power-law, with exponent -n/a – 1. The presented mechanism shows that power-laws can arise in generic situations different from previously considered specialized systems such as multi-particle systems close to phase transitions, dynamical systems at bifurcation points or systems displaying self-organized criticality. Thus, the presented mechanism may serve as an alternative hypothesis in system identification problems. 展开更多
关键词 Heavy-Tailed DISTRIBUTIONS random Sampling GAUSSIAN EXPONENTIAL power-law
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双边投资协定网络的演化机制——基于多维邻近性视角 被引量:1
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作者 王群勇 苗培 李月 《河北经贸大学学报》 CSSCI 北大核心 2024年第3期84-97,共14页
利用社会网络分析方法考察了双边投资协定(BITs)网络的历史演化特征与驱动机制。研究发现,BITs网络大致经历了初步形成、迅猛发展和结构调整三个阶段,呈现出一个较完整的S型增长,网络核心—半核心—边缘结构实现了由“金字塔”向“橄榄... 利用社会网络分析方法考察了双边投资协定(BITs)网络的历史演化特征与驱动机制。研究发现,BITs网络大致经历了初步形成、迅猛发展和结构调整三个阶段,呈现出一个较完整的S型增长,网络核心—半核心—边缘结构实现了由“金字塔”向“橄榄球”的转变。以多维邻近性为视角,运用时间指数随机图模型对BITs网络形成的影响因素进行分析,结果显示,多维邻近性是驱动BITs网络形成的重要力量,经济和制度邻近性对BITs关系的形成有负向影响,贸易水平、地理和社会邻近性对BITs关系的形成有正向影响。然而,2008年金融危机改变了BITs网络的结构特征,金融危机后BITs网络呈现分散化、多边化发展趋势,某些邻近性变量影响不再显著,社会环境类因素成为影响BITs网络的关键因素。 展开更多
关键词 双边投资协定 社会网络 时间指数随机图模型 多维邻近性
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基于指数随机图模型的发明者合作网络形成机制研究 被引量:1
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作者 林润辉 季泽 《科技进步与对策》 CSSCI 北大核心 2024年第13期131-140,共10页
聚焦探讨不同因素是否以及如何影响发明者合作网络形成,基于2004—2021年华为在中国申请的专利数据,构建发明者合作网络,运用指数随机图模型探讨行动者属性和内生结构效应对发明者合作网络形成的影响机理。结果表明:发明者合作网络是稀... 聚焦探讨不同因素是否以及如何影响发明者合作网络形成,基于2004—2021年华为在中国申请的专利数据,构建发明者合作网络,运用指数随机图模型探讨行动者属性和内生结构效应对发明者合作网络形成的影响机理。结果表明:发明者合作网络是稀疏网络,呈现星形结构和闭合三角形结构共存的网络结构模式;发明者协同创新能力抑制新合作关系的形成,但发明者合作伙伴多样性和合作深度均促进新合作关系的形成,且具有相同水平合作伙伴多样性或合作深度的发明者之间更容易建立合作关系;发明者倾向于与处于中心位置的发明者建立合作关系以及与具有共同合作伙伴的直接合作伙伴建立新合作关系。 展开更多
关键词 发明者合作网络 指数随机图模型 内生结构效应 网络形成机制
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中国省域交通碳排放空间关联格局的驱动特征
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作者 杨青 郭露 +1 位作者 刘星星 赵坤强 《中国环境科学》 EI CAS CSCD 北大核心 2024年第2期1171-1184,共14页
利用我国2003~2020年省级交通碳排放数据,基于模体结构分析和指数随机图模型对中国交通碳排放空间关联网络的宏观格局、微观连通和驱动特征进行研究.结果表明,中国交通碳排放空间关联网络呈现周期波动特征,等级均衡化发展和核心虹吸的... 利用我国2003~2020年省级交通碳排放数据,基于模体结构分析和指数随机图模型对中国交通碳排放空间关联网络的宏观格局、微观连通和驱动特征进行研究.结果表明,中国交通碳排放空间关联网络呈现周期波动特征,等级均衡化发展和核心虹吸的空间分布,演化出少核心—多半核心—边缘新格局,碳转移路径表现出明显的空间惰性与时间惯性以及区域集中性;经纪属性在推动跨区域交通协同减排的经济活动中发挥重要作用;内生网络的互惠性、连通性、集聚性对交通碳排放网络形成具有重要驱动作用,行为者属性中发出、接收、抑制、互惠的驱动关系明显,外部网络的影响具有明显的地理邻近效应,呈现出地理距离衰减规律特征.由此提出短期重大项目驱动,推动绿色交通转型联动;中期提升协同水平,加强跨区域交通碳减排协调机制;长期顶层零碳设计,工业化-产业化-市场化全面协同等政策建议. 展开更多
关键词 交通碳排放 模体结构分析 指数随机图模型 驱动要素
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基于多查询的社交网络关键节点挖掘算法
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作者 辛国栋 朱滕威 +3 位作者 黄俊恒 魏家扬 刘润萱 王巍 《网络与信息安全学报》 2024年第1期79-90,共12页
关键节点挖掘是复杂网络领域的研究重点和热点。针对社交网络中关键嫌疑人挖掘问题,提出基于多查询的社交网络关键节点挖掘算法。该算法将已知嫌疑人作为查询节点,提取其所在的局部拓扑结构,并计算局部拓扑结构中非查询节点的关键程度,... 关键节点挖掘是复杂网络领域的研究重点和热点。针对社交网络中关键嫌疑人挖掘问题,提出基于多查询的社交网络关键节点挖掘算法。该算法将已知嫌疑人作为查询节点,提取其所在的局部拓扑结构,并计算局部拓扑结构中非查询节点的关键程度,从中选择关键程度较高的节点进行推荐。针对现有方法中关键节点计算复杂度高、已知查询节点信息难以有效利用的问题,提出一个两阶段的基于多查询的社交网络关键节点挖掘算法,整合多查询节点的局部拓扑信息和全局节点聚合特征信息,将计算范围从全局缩减到局部,进而对相关节点的关键程度进行量化。具体而言,利用带重启策略的随机游走算法获得多个查询节点的局部拓扑结构;为了得到节点的嵌入向量,基于graphsage模型构建一种无监督的图神经网络模型,该模型结合节点的自身特征和邻居聚合特征来生成嵌入向量,从而为算法框架的相似度计算提供信息输入。基于与查询节点特征的相似性,衡量局部拓扑中节点的关键程度。实验结果显示,所提算法在时间效率和结果有效性方面均优于传统关键节点挖掘算法。 展开更多
关键词 社交网络 随机游走 图神经网络 节点嵌入向量 关键节点
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新发展格局下以城市循环能力增强国内大循环内生动力的模式和机制研究
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作者 周密 王威华 李月 《南开经济研究》 CSSCI 北大核心 2024年第4期148-167,共20页
“增强国内大循环内生动力”是新形势新条件下对构建新发展格局提出的重大要求之一。本文提出“城市节点-城市群块-流关系链-双向循环网”的研究框架,以289个城市的循环能力衡量城市供需的特征性事实,并运用投入产出表和社会网络分析方... “增强国内大循环内生动力”是新形势新条件下对构建新发展格局提出的重大要求之一。本文提出“城市节点-城市群块-流关系链-双向循环网”的研究框架,以289个城市的循环能力衡量城市供需的特征性事实,并运用投入产出表和社会网络分析方法刻画国内大循环网络,探究以城市循环能力增强国内大循环内生动力的模式和作用机制。研究发现,第一,样本期城市循环能力面临着联动性不畅、均衡性不足和协调性不强的三重结构性困境;第二,破解三重结构性困境需要认识城市在国内大循环网络中的中间人角色及其联动模式。联动性不畅是由于联络人不多,均衡性不足是由于协调人角色较少,协调性不强是由于守门人和联络人较少;第三,在上述联动模式的基础上,本文从城市循环能力内生性、网络结构动力双重性和中间人作用异质性等多重角度,采用指数随机图模型实证探究城市循环能力增强国内大循环内生动力的模式与机制。本文对于如何从城市层面增强国内大循环内生动力,助力新发展格局构建具有借鉴意义。 展开更多
关键词 城市循环能力 国内大循环 内生动力 指数随机图模型
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基于深度学习框架的时空联合供水管网漏损检测研究
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作者 蒋白懿 牟天蔚 +3 位作者 李维轲 王康 肖敏 王鑫 《给水排水》 CSCD 北大核心 2024年第6期152-158,共7页
以深度学习框架为基础,提出了一种时空联合供水管网漏损检测模型。该模型首先运用Node2Vec算法求解不同时间段内节点特征;其次,通过模糊C-均值聚类法,利用管网模型节点特征进行分区。最后,以不同时间段的压力敏感度作为输入,漏损位置的... 以深度学习框架为基础,提出了一种时空联合供水管网漏损检测模型。该模型首先运用Node2Vec算法求解不同时间段内节点特征;其次,通过模糊C-均值聚类法,利用管网模型节点特征进行分区。最后,以不同时间段的压力敏感度作为输入,漏损位置的分区号作为标签,通过深度信念神经网络进行训练,并通过训练后的模型对管网漏损位置进行检测。在实例分析中,以A市实际供水管网拓扑结构进行验证,利用MATLAB-Open Water Analytics toolbox联合编程建模,结果表明,各个时间段的检测效果均较优,正确率均达到为80%以上。因此,该模型能够有效地检测管网漏损。 展开更多
关键词 Node2Vec 深度学习 漏损定位 随机游走 图嵌入
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基于知识图谱的SMT产线工艺推荐与优化
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作者 刘潇龙 李鑫 +1 位作者 朱孟达 黄文艳 《机械设计与制造工程》 2024年第6期122-126,共5页
面向复杂电路板组件产品,依赖人工经验设计表面贴装技术(SMT)工艺的传统方法存在准确度与适配度低、设计效率低、实物试错成本高等问题,提出了一种基于知识图谱的SMT产线工艺推荐与优化算法。建立知识图谱系统描述SMT产线工艺参数之间... 面向复杂电路板组件产品,依赖人工经验设计表面贴装技术(SMT)工艺的传统方法存在准确度与适配度低、设计效率低、实物试错成本高等问题,提出了一种基于知识图谱的SMT产线工艺推荐与优化算法。建立知识图谱系统描述SMT产线工艺参数之间的关系,利用随机森林算法计算各个参数重要度,更新参数权重推荐合适参数,并与完全平均加权法对比,验证了其准确性与稳定性。 展开更多
关键词 表面贴装技术 工艺参数 知识图谱 随机森林算法
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中国与OECD国家留学生流动网络的空间格局与影响机制
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作者 杨雨晴 丁子军 戴靓 《地理科学》 CSSCI CSCD 北大核心 2024年第10期1758-1768,共11页
构建和推动高质量人才环流是中国国际人才培养和人才磁石型国家建设的重要途径。本文基于2019年中国与38个经济合作与发展组织(OECD)成员国之间高等学校留学生流动数据,构建有向加权的国际人才流动网络,并运用社会网络分析探讨国际人才... 构建和推动高质量人才环流是中国国际人才培养和人才磁石型国家建设的重要途径。本文基于2019年中国与38个经济合作与发展组织(OECD)成员国之间高等学校留学生流动数据,构建有向加权的国际人才流动网络,并运用社会网络分析探讨国际人才流动的空间格局与影响机制。结果显示:① 39个国家之间留学生交流密切,区域组团明显,形成北美亚太组团、南美欧洲组团、北欧波罗的海组团、捷克斯洛伐克组团。中国和美国是国际人才交流的中心,同时中国、英国、德国、美国、法国也是人才流动的门户与枢纽。②各国家在输出和接收留学生上存在非对称性。中国留学生流出量占总网络的近50%,而OECD各国输出量相对均衡。美国、英国、澳大利亚成为留学生流入量排名前3,中国以7.17%的占比居第四。③国家的开放程度、教育质量、经济水平对留学生流动的影响均存在发送者效应和接收者效应,地理、语言文化、贸易方面的邻近可促进留学生流动。结构依赖是留学生流动的重要驱动力,其中互惠效应、择优依附效应与传递闭合效应最为显著,对于外生动力具有一定的替代性。中国与OECD国家间的人才联系仍有较大的提升空间,需从个体属性、多维邻近性和结构内生性方面进行优化,促进区域内人才更加扁平化多元化交流发展。 展开更多
关键词 人才流动 留学生网络 社会网络分析 指数随机图模型
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