In this article the C n graphs are introduced, by which a characterization of the embeddability of a graph on either an orientable surface or a non orientable surface is provided.
Purpose:To contribute to the study of networks and graphs.Design/methodology/approach:We apply standard mathematical thinking.Findings:We show that the distance distribution in an undirected network Lorenz majorizes t...Purpose:To contribute to the study of networks and graphs.Design/methodology/approach:We apply standard mathematical thinking.Findings:We show that the distance distribution in an undirected network Lorenz majorizes the one of a chain.As a consequence,the average and median distances in any such network are smaller than or equal to those of a chain.Research limitations:We restricted our investigations to undirected,unweighted networks.Practical implications:We are convinced that these results are useful in the study of small worlds and the so-called six degrees of separation property.Originality/value:To the best of our knowledge our research contains new network results,especially those related to frequencies of distances.展开更多
The reconstruction of high-resolution sea-level variation curves in deep time based on the standard car-bonate microfacies knowledge graph(SMFKG)is of great scientific significance for exploring the Earth system evolu...The reconstruction of high-resolution sea-level variation curves in deep time based on the standard car-bonate microfacies knowledge graph(SMFKG)is of great scientific significance for exploring the Earth system evolution and predicting future sea-level and climate changes.In this study,the concepts,attri-butes,and relationships among standard carbonate microfacies(SMF)are comprehensively analyzed;an ontology layer is established and its data layer is constructed using thin-section descriptions;and finally,the SMFKG is established.Additionally,based on the knowledge graph,an application for automatically identifying SMF using identification markers and reconstructing the high-resolution relative sea-level variation curve using the SMF and facies zones is compiled.Then,all thin sections of the late Ediacaran Dengying Formation in the western margin of the Yangtze Platform are observed and described in detail,the SMF and facies zones are identified automatically,and the relative sea-level curve is recon-structed automatically using the SMFKG.The reconstruction results show that the Yangtze Platform experienced four sea-level rise and fall cycles in the late Ediacaran,of which two intense regressions led to subaerial-exposed unconformities in the interior and top of the Dengying Formation,which is highly consistent with previous research results.This shows that the high-resolution relative sea-level variation curve in deep time can be reconstructed efficiently and intelligently using the SMFKG.Additionally,in the near future,the combination of an automatic digital slide-scanning system,machine-learning techniques,and the SMFKG can achieve one-stop fully automatic SMF recognition and reconstruction of high-resolution relative sea-level variation curves in deep time,which has a high application value.展开更多
大部分检测方法针对平稳信号设计,使用单一统计模型分析检测性能,面对语音信号及复杂环境噪声时,效果常因模型失配而变差。为探索具有较高鲁棒性的语音信号检测方法,将语音信号与不同环境噪声混合并将其映射为图,设计基于图结构的语音...大部分检测方法针对平稳信号设计,使用单一统计模型分析检测性能,面对语音信号及复杂环境噪声时,效果常因模型失配而变差。为探索具有较高鲁棒性的语音信号检测方法,将语音信号与不同环境噪声混合并将其映射为图,设计基于图结构的语音信号检测方法。通过实验比较该方法与传统M2M4方法的性能。对比受试者工作特征(ReceiverOperating Characteristic,ROC)曲线和曲线下面积(Area Under Curve,AUC)值,图检测方法均优于M2M4方法的检测性能。在不同实验条件下,基于图检测方法的信号检测具有更优的检测性能。展开更多
文摘In this article the C n graphs are introduced, by which a characterization of the embeddability of a graph on either an orientable surface or a non orientable surface is provided.
文摘Purpose:To contribute to the study of networks and graphs.Design/methodology/approach:We apply standard mathematical thinking.Findings:We show that the distance distribution in an undirected network Lorenz majorizes the one of a chain.As a consequence,the average and median distances in any such network are smaller than or equal to those of a chain.Research limitations:We restricted our investigations to undirected,unweighted networks.Practical implications:We are convinced that these results are useful in the study of small worlds and the so-called six degrees of separation property.Originality/value:To the best of our knowledge our research contains new network results,especially those related to frequencies of distances.
基金supported by the IUGS Deep-time Digital Earth(DDE)Big Science Program,National Natural Science Foundation of China(No.42050104,No.42102138 and No.U19B6003)the Open Fund(DGERA20221103)of Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural ResourcesChengdu University of Technology,China and the Open Fund(PLC20210202)of the State Key Labora-tory of Oil and Gas Reservoir Geology and Exploitation(Chengdu University of Technology,China).
文摘The reconstruction of high-resolution sea-level variation curves in deep time based on the standard car-bonate microfacies knowledge graph(SMFKG)is of great scientific significance for exploring the Earth system evolution and predicting future sea-level and climate changes.In this study,the concepts,attri-butes,and relationships among standard carbonate microfacies(SMF)are comprehensively analyzed;an ontology layer is established and its data layer is constructed using thin-section descriptions;and finally,the SMFKG is established.Additionally,based on the knowledge graph,an application for automatically identifying SMF using identification markers and reconstructing the high-resolution relative sea-level variation curve using the SMF and facies zones is compiled.Then,all thin sections of the late Ediacaran Dengying Formation in the western margin of the Yangtze Platform are observed and described in detail,the SMF and facies zones are identified automatically,and the relative sea-level curve is recon-structed automatically using the SMFKG.The reconstruction results show that the Yangtze Platform experienced four sea-level rise and fall cycles in the late Ediacaran,of which two intense regressions led to subaerial-exposed unconformities in the interior and top of the Dengying Formation,which is highly consistent with previous research results.This shows that the high-resolution relative sea-level variation curve in deep time can be reconstructed efficiently and intelligently using the SMFKG.Additionally,in the near future,the combination of an automatic digital slide-scanning system,machine-learning techniques,and the SMFKG can achieve one-stop fully automatic SMF recognition and reconstruction of high-resolution relative sea-level variation curves in deep time,which has a high application value.
文摘大部分检测方法针对平稳信号设计,使用单一统计模型分析检测性能,面对语音信号及复杂环境噪声时,效果常因模型失配而变差。为探索具有较高鲁棒性的语音信号检测方法,将语音信号与不同环境噪声混合并将其映射为图,设计基于图结构的语音信号检测方法。通过实验比较该方法与传统M2M4方法的性能。对比受试者工作特征(ReceiverOperating Characteristic,ROC)曲线和曲线下面积(Area Under Curve,AUC)值,图检测方法均优于M2M4方法的检测性能。在不同实验条件下,基于图检测方法的信号检测具有更优的检测性能。
