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Information Geometric Structures for the Thermodynamic Manifold
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作者 张士诚 孙华飞 李春辉 《Journal of Beijing Institute of Technology》 EI CAS 2010年第4期491-494,共4页
In view of information geometry,the state space S of thermodynamic parameters is investigated.First a Riemannian metric for S is defined and then the α-geometric structures of S is given.Some of results obtained by o... In view of information geometry,the state space S of thermodynamic parameters is investigated.First a Riemannian metric for S is defined and then the α-geometric structures of S is given.Some of results obtained by other authors are extended. 展开更多
关键词 thermodynamic manifold information geometry geometric structure
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Fine Structure Constant Model Demonstrates the Electron Elementary Charge of Having an Intrinsic Manifold
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作者 Emmanouil Markoulakis Emmanuel Antonidakis 《Journal of Applied Mathematics and Physics》 2022年第10期2923-2939,共17页
Using our recently published electron’s charge electromagnetic flux manifold fiber model of the electron, described by analytical method and numerical simulations, we show how the fine structure constant is embedded ... Using our recently published electron’s charge electromagnetic flux manifold fiber model of the electron, described by analytical method and numerical simulations, we show how the fine structure constant is embedded as a geometrical proportionality constant in three dimensional space of its charge manifold and how this dictates the first QED term one-loop contribution of its anomalous magnetic moment making for the first time a connection of its intrinsic characteristics with physical geometrical dimensions and therefore demonstrating that the physical electron charge cannot be dimensionless. We show that the fine structure constant (FSC) α, and anomalous magnetic moment α<sub>μ</sub> of the electron is related to the sphericity of its charge distribution which is not perfectly spherical and thus has a shape, and therefore its self-confined charge possesses measurable physical dimensions. We also explain why these are not yet able to be measured by past and current experiments and how possible we could succeed. 展开更多
关键词 Electron Charge manifold Electron Fiber Model Compton Electron Fine structure Constant Anomalous Magnetic Moment Electron Dipole Moment Classical Electrodynamics Electron Geometry
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HAMILTONIAN STRUCTURE FOR RIGID BODY WITH FLEXIBLE ATTACHMENTS IN A CIRCULAR ORBIT 被引量:1
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作者 程耀 黄克累 陆启韶 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1993年第1期72-79,共8页
Hamiltonian structure of a rigid body in a circular orbit is established in this paper. With the reduction technique, the Hamiltonian structure of a rigid body in a circular orbit is derived from Lie-Poisson structure... Hamiltonian structure of a rigid body in a circular orbit is established in this paper. With the reduction technique, the Hamiltonian structure of a rigid body in a circular orbit is derived from Lie-Poisson structure of semidirect product, and Hamiltonian is derived from Jacobi's integral. The above method can be generalized to establish the Hamiltonian structure of a rigid body with a flexible attachment in a circular or- bit. At last, an example of stability analysis is given. 展开更多
关键词 Hamiltonian structure Poisson manifold rigid-elastic coupled system semidirect product circular orbit
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Recent developments in the structural design and optimization of ITER neutral beam manifold
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作者 曹诚志 潘宇东 +3 位作者 夏志伟 李波 江涛 李伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第2期180-185,共6页
This paper describes a new design of the neutral beam manifold based on a more optimized support system.A proposed alternative scheme has presented to replace the former complex manifold supports and internal pipe sup... This paper describes a new design of the neutral beam manifold based on a more optimized support system.A proposed alternative scheme has presented to replace the former complex manifold supports and internal pipe supports in the final design phase.Both the structural reliability and feasibility were confirmed with detailed analyses.Comparative analyses between two typical types of manifold support scheme were performed.All relevant results of mechanical analyses for typical operation scenarios and fault conditions are presented.Future optimization activities are described,which will give useful information for a refined setting of components in the next phase. 展开更多
关键词 ITER neutral beam manifold optimized design on supports structural seismic analysis
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Spontaneous Emergence of Physical Structures and Observable Formations: Fluctuations, Waves, Turbulent Pulsations and So on
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作者 L. I. Petrova 《Journal of Applied Mathematics and Physics》 2016年第5期863-870,共8页
As it is known, the closed inexact exterior form and associated closed dual form make up a differential-geometrical structure. Such a differential-geometrical structure describes a physical structure, namely, a pseudo... As it is known, the closed inexact exterior form and associated closed dual form make up a differential-geometrical structure. Such a differential-geometrical structure describes a physical structure, namely, a pseudostructure on which conservation laws are fulfilled (A closed dual form describes a pseudostructure. And a closed exterior form, as it is known, describes a conservative quantity, since the differential of closed form is equal to zero). It has been shown that closed inexact exterior forms, which describe physical structures, are obtained from the equations of mathematical physics. This process proceeds spontaneously under realization of any degrees of freedom of the material medium described. Such a process describes an emergence of physical structures and this is accompanied by an appearance of observed formations such as fluctuations, waves, turbulent pulsations and so on. 展开更多
关键词 Skew-Symmetric Form Nonidentical Relation Degenerate Transformation the Transition from the Nonintegrable manifolds to the Integrable structures
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基于包络学习和分级结构一致性机制的不平衡集成算法
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作者 李帆 张小恒 +1 位作者 李勇明 王品 《电子学报》 EI CAS CSCD 北大核心 2024年第3期751-761,共11页
集成方法是不平衡学习方法的重要分支,然而,现有不平衡集成方法均作用于原样本而没考虑样本的结构信息,因此其效能仍然有限.样本的结构信息包括局部和全局结构信息.为了解决上述问题,本文提出了一种基于深度样本包络网络(Deep Instance ... 集成方法是不平衡学习方法的重要分支,然而,现有不平衡集成方法均作用于原样本而没考虑样本的结构信息,因此其效能仍然有限.样本的结构信息包括局部和全局结构信息.为了解决上述问题,本文提出了一种基于深度样本包络网络(Deep Instance Envelope Network,DIEN)和分级结构一致性机制(Hierarchical Structure Consistency Mechanism,HSCM)的不平衡集成学习算法.该算法在考虑局部流形和全局结构信息的情况下,通过多层样本聚类,生成高质量的多层包络样本,从而实现类平衡化.首先,算法基于样本近邻拼接和模糊C均值聚类算法,设计DIEN来挖掘样本的结构信息,得到深度包络样本.然后,设计局部流形结构度量和全局结构分布度量来构建HSCM用于增强层间样本的分布一致性.接着,将DIEN和HSCM结合起来,构建出优化后的深度样本包络网络——DH(DIEN with HSCM).之后,将基分类器应用于包络样本.最后,设计bagging集成学习机制来融合基分类器的预测结果.文末组织了多组实验,采用了十多个公共数据集和有代表性的相关算法进行验证比较.实验结果表明,本文算法在AUC(Area Under Curve),F-measure等四个性能指标上显著最优. 展开更多
关键词 不平衡学习 包络学习 分级结构一致性机制 局部流形结构度量 全局结构分布度量
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基于内嵌式微通道芯片散热结构设计研究综述
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作者 熊园园 刘沛 +2 位作者 付予 焦斌斌 芮二明 《集成电路与嵌入式系统》 2024年第7期12-18,共7页
电子芯片/系统的尺寸微型化、功能复合化导致了其功率密度的增大,伴随着发热也越来越严重,如何应对电子芯片/系统逐渐增加的热流密度,成为散热设计中面临的巨大挑战,也是当前研究的热点。本文详细论述了传统散热技术的优缺点,对国内外... 电子芯片/系统的尺寸微型化、功能复合化导致了其功率密度的增大,伴随着发热也越来越严重,如何应对电子芯片/系统逐渐增加的热流密度,成为散热设计中面临的巨大挑战,也是当前研究的热点。本文详细论述了传统散热技术的优缺点,对国内外正在开展的内嵌式微通道散热结构进行了系统分析,并着重对基于内嵌式微通道芯片散热技术原理、散热性能和创新性解决方案进行了归纳总结。在分析当前国内外解决方案的基础上,总结了基于内嵌式微通道的芯片散热设计经验和结论,以及面临的挑战,基于此给出了芯片散热设计研究现状和发展方向。 展开更多
关键词 芯片散热 内嵌式微通道 热流密度 散热结构 分层复杂歧管
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浅水受限区水下油气田开发方案
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作者 孟凡然 张重德 +3 位作者 曹永 张文龙 王刚 贾鹏 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第4期779-785,共7页
针对国内浅水油气资源开发环境影响及空间受限等问题,本文提出了国产浅水水下生产系统的总体设计方案。通过对浅水水下生产系统关键设备结构进行分析,提出了一种满足受限区海域开发要求的环境友好型设计思路。结果表明:通过系统和总体... 针对国内浅水油气资源开发环境影响及空间受限等问题,本文提出了国产浅水水下生产系统的总体设计方案。通过对浅水水下生产系统关键设备结构进行分析,提出了一种满足受限区海域开发要求的环境友好型设计思路。结果表明:通过系统和总体布置的设计,国产浅水水下生产系统与深水相比在单体重量、作业方式、维护检修方面更加经济。 展开更多
关键词 浅水采油树 浅水水下控制模块 水下防护结构 浅水水下生产系统 水下管汇 湿插拔水下电连接器 水下湿插拔液压连接器 节流阀
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基于流固耦合的水下发球管汇力学及振动特性分析
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作者 鞠朋朋 柳英明 +1 位作者 张欢 李林 《科学技术与工程》 北大核心 2024年第4期1471-1479,共9页
水下发球系统具有可利用生产流体发球、不停井发球的优势,在现阶段与未来海洋油气开发具有广阔的应用前景。水下发球管汇结构复杂,存在多处弯管、变径三通,生产流体压力高,而发球工艺操作引起的管汇结构变形与振动情况尚不清晰。采用数... 水下发球系统具有可利用生产流体发球、不停井发球的优势,在现阶段与未来海洋油气开发具有广阔的应用前景。水下发球管汇结构复杂,存在多处弯管、变径三通,生产流体压力高,而发球工艺操作引起的管汇结构变形与振动情况尚不清晰。采用数值模拟的方法,计算了某水下发球管汇在发球工况中,流固耦合条件下管汇结构的位移、应力分布及振动情况。发现阀门的开关瞬间是压力变化幅度最大的特征时刻,也是引起管道位移、振动情况最严重的特征时刻;明确了管道结构风险位点为管汇结构末端,最大位移约为5.69 mm,主要由X方向贡献,最大等效应力为233.13 MPa,主要集中分布在T型管、弯管内侧处;提出了针对性的优化支撑方案,管汇结构最大位移降低至3.53 mm,低阶模态频率增幅约为1.74%~20.54%,说明管汇结构的安全性得到了提高。研究成果可为水下发球管汇的设计、运行提供理论依据。 展开更多
关键词 数值模拟 流固耦合 水下发球管汇 力学特性 振动特性
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鉴别流形敏感的跨模态轴承故障诊断方法
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作者 朱彦敏 苏树智 《重庆工商大学学报(自然科学版)》 2024年第3期113-118,共6页
目的在实际应用中采集的原始多模态故障数据通常是包含大量噪声和冗余信息的非线性数据,如何从不同故障模态中提取有效的非线性故障特征仍是一个挑战性的问题。方法提出了一种鉴别流形敏感的跨模态故障诊断方法,在该方法中首先借助相关... 目的在实际应用中采集的原始多模态故障数据通常是包含大量噪声和冗余信息的非线性数据,如何从不同故障模态中提取有效的非线性故障特征仍是一个挑战性的问题。方法提出了一种鉴别流形敏感的跨模态故障诊断方法,在该方法中首先借助相关分析理论在跨模态故障空间中构建了不同模态间的相关系数,并通过理论推导获得了相关系数的等价优化模型,然后利用局部近邻图构建了鉴别流形敏感散布,进而通过最大化不同模态间的相关性和最小化鉴别流形敏感散布,形成了鉴别流形敏感的跨模态故障诊断模型,并且在理论上推导出了该优化模型的解析解,从而能够从不同模态的故障数据中学习强鉴别力的非线性故障特征。结果在德国帕德博恩轴承数据集和多模态轴承故障数据集上设计了针对性实验,实验结果显示在少量故障样本用于训练时即可获得良好的诊断准确性。结论提出的方法是一种有效的跨模态故障诊断方法。 展开更多
关键词 故障诊断 跨模态故障特征抽取 鉴别流形结构
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4MZ-4自走箱式采棉机风送歧管流体分析及结构优化
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作者 张泽朋 林兆焯 +2 位作者 巩鹏 王萧 黄开鹏 《新疆农机化》 2024年第2期35-37,47,共4页
针对最新研制的4MZ-4自走箱式采棉机,为分析其风送系统流动特性,并使风量在四个输送管路中分配均匀,利用Hypermesh、Fluent软件对四行机离心风机及一分四歧管进行了流体域建模及数值分析,分析得到离心风机出口流量数据,以风机出口流量... 针对最新研制的4MZ-4自走箱式采棉机,为分析其风送系统流动特性,并使风量在四个输送管路中分配均匀,利用Hypermesh、Fluent软件对四行机离心风机及一分四歧管进行了流体域建模及数值分析,分析得到离心风机出口流量数据,以风机出口流量作为歧管入口边界条件计算歧管各出口流量及流量配比,并根据歧管内空气流动状态对歧管结构进行优化,优化后歧管的风量配比均匀性得到显著改善。 展开更多
关键词 采棉机 风送歧管 流体分析 结构优化
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Two theorems on cosymplectic hypersurfaces of six-dimensional Hermitian submanifolds of Cayley algebra 被引量:1
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作者 Mihail Banaru (Smolensk University of Humanities, Smolensk 214014, Russia) 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第1期38-40,共3页
Proves that cosymplectic hypersurfaces of six dimensional Hermitian submanifolds of the octave algebra are ruled manifolds and establishes a necessary and sufficient condition for a cosymplectic hypersurface of Hermit... Proves that cosymplectic hypersurfaces of six dimensional Hermitian submanifolds of the octave algebra are ruled manifolds and establishes a necessary and sufficient condition for a cosymplectic hypersurface of Hermitian M 6 O  to be a minimal submanifold of M 6. 展开更多
关键词 Hermitian manifold almost contact metric structure ruled manifold minimal submanifold cosymplectic structure
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Embeddings of Almost Hermitian Manifold in Almost Hyper Hermitian Manifold and Complex (Hypercomplex) Numbers in Riemannian Geometry 被引量:1
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作者 Alexander A Ermolitski 《Applied Mathematics》 2014年第16期2464-2475,共12页
Tubular neighborhoods play an important role in differential topology. We have applied these constructions to geometry of almost Hermitian manifolds. At first, we consider deformations of tensor structures on a normal... Tubular neighborhoods play an important role in differential topology. We have applied these constructions to geometry of almost Hermitian manifolds. At first, we consider deformations of tensor structures on a normal tubular neighborhood of a submanifold in a Riemannian manifold. Further, an almost hyper Hermitian structure has been constructed on the tangent bundle TM with help of the Riemannian connection of an almost Hermitian structure on a manifold M then, we consider an embedding of the almost Hermitian manifold M in the corresponding normal tubular neighborhood of the null section in the tangent bundle TM equipped with the deformed almost hyper Hermitian structure of the special form. As a result, we have obtained that any Riemannian manifold M of dimension n can be embedded as a totally geodesic submanifold in a Kaehlerian manifold of dimension 2n (Theorem 6) and in a hyper Kaehlerian manifold of dimension 4n (Theorem 7). Such embeddings are “good” from the point of view of Riemannian geometry. They allow solving problems of Riemannian geometry by methods of Kaehlerian geometry (see Section 5 as an example). We can find similar situation in mathematical analysis (real and complex). 展开更多
关键词 RIEMANNIAN manifolds ALMOST HERMITIAN and ALMOST HYPER HERMITIAN structures TANGENT Bundle
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The U-Kenmotsu Hypersurfaces Axiom and Six-Dimensional Hermitian Submanifolds of Cayley Algebra
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作者 Mihail BANARU 《四川理工学院学报(自然科学版)》 CAS 2013年第3期1-5,共5页
Six-dimensional Hermitian submanifolds of Cayley algebra are considered.It is proved that if such a submanifold of the octave algebta complies with the U-Kenmotsu hypersurfaces axiom,then it is Khlerian.
关键词 almost contact metric structure Kenmotsu structure Khlerian manifold almost Hermitian manifold
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ON THE INVARIANT SUBMANIFOLDS OF RIEMANNIAN PRODUCT MANIFOLD
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作者 M.Atceken S.Keles 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期549-558,共10页
In this paper, the vertical and horizontal distributions of an invariant sub-manifold of a Riemannian product manifold are discussed. An invariant real space form in a Riemannian product manifold is researched. Finall... In this paper, the vertical and horizontal distributions of an invariant sub-manifold of a Riemannian product manifold are discussed. An invariant real space form in a Riemannian product manifold is researched. Finally, necessary and sufficient conditions are given on an invariant submanifold of a Riemannian product manifold to be a locally symmetric and real space form. 展开更多
关键词 Riemannian product manifold mixed geodesic submanifold real space form and almost Riemannian product structure
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Semi-Supervised Dimensionality Reduction of Hyperspectral Image Based on Sparse Multi-Manifold Learning
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作者 Hong Huang Fulin Luo +1 位作者 Zezhong Ma Hailiang Feng 《Journal of Computer and Communications》 2015年第11期33-39,共7页
In this paper, we proposed a new semi-supervised multi-manifold learning method, called semi- supervised sparse multi-manifold embedding (S3MME), for dimensionality reduction of hyperspectral image data. S3MME exploit... In this paper, we proposed a new semi-supervised multi-manifold learning method, called semi- supervised sparse multi-manifold embedding (S3MME), for dimensionality reduction of hyperspectral image data. S3MME exploits both the labeled and unlabeled data to adaptively find neighbors of each sample from the same manifold by using an optimization program based on sparse representation, and naturally gives relative importance to the labeled ones through a graph-based methodology. Then it tries to extract discriminative features on each manifold such that the data points in the same manifold become closer. The effectiveness of the proposed multi-manifold learning algorithm is demonstrated and compared through experiments on a real hyperspectral images. 展开更多
关键词 HYPERSPECTRAL IMAGE Classification Dimensionality Reduction Multiple manifoldS structure SPARSE REPRESENTATION SEMI-SUPERVISED Learning
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Smoother manifold for graph meta-learning
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作者 赵文仓 WANG Chunxin XU Changkai 《High Technology Letters》 EI CAS 2022年第1期48-55,共8页
Meta-learning provides a framework for the possibility of mimicking artificial intelligence.How-ever,data distribution of the training set fails to be consistent with the one of the testing set as the limited domain d... Meta-learning provides a framework for the possibility of mimicking artificial intelligence.How-ever,data distribution of the training set fails to be consistent with the one of the testing set as the limited domain differences among them.These factors often result in poor generalization in existing meta-learning models.In this work,a novel smoother manifold for graph meta-learning(SGML)is proposed,which derives the similarity parameters of node features from the relationship between nodes and edges in the graph structure,and then utilizes the similarity parameters to yield smoother manifold through embedded propagation module.Smoother manifold can naturally filter out noise from the most important components when generalizing the local mapping relationship to the global.Besides suiting for generalizing on unseen low data issues,the framework is capable to easily perform transductive inference.Experimental results on MiniImageNet and TieredImageNet consistently show that applying SGML to supervised and semi-supervised classification can improve the performance in reducing the noise of domain shift representation. 展开更多
关键词 META-LEARNING smoother manifold similarity parameter graph structure
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瞬态流固耦合作用下天然气发电内燃机排气歧管结构优化设计 被引量:2
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作者 杨汉乾 马金浩 +2 位作者 胡志坚 易仲威 付建勤 《重庆理工大学学报(自然科学)》 CAS 北大核心 2023年第4期286-293,共8页
天然气发动机用于发电用途后,工作时间长,排气温度高。车用柴油机改制成燃气发电内燃机后,为了进一步改善燃油经济性和提高排气歧管的可靠性,通过一、三维仿真建模对排气歧管结构进行优化。研究认为原机排气歧管为了兼顾低转速的性能,... 天然气发动机用于发电用途后,工作时间长,排气温度高。车用柴油机改制成燃气发电内燃机后,为了进一步改善燃油经济性和提高排气歧管的可靠性,通过一、三维仿真建模对排气歧管结构进行优化。研究认为原机排气歧管为了兼顾低转速的性能,管径设计较小,在1500 r/min时排气背压较大,不适宜应用在改制后的燃气发电内燃机。本研究经过一维数值计算,通过优化管径可以降低线工况下的燃气消耗,并且提高了工作功率。其次通过逆向建模方法和Fluent UDF模块建立流固耦合瞬态仿真模型,耦合计算了5个工作循环中的3个时间点,并且提出了2种排气歧管的结构优化方法,进行了排温瞬变过程中的热负荷分析和对比。结果表明增加加强筋结构的方案在节省材料的基础上可进一步减少热变形量,有利于提高排气歧管的寿命,满足燃气发电内燃机的设计要求。建模和优化方法可为燃气发电内燃机排气管的设计提供参考。 展开更多
关键词 天然气发动机 排气歧管 流固耦合 结构优化 热负荷分析
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基于局部敏感判别宽度学习的高光谱图像分类 被引量:1
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作者 曹鹤玲 宋昌隆 楚永贺 《计算机应用研究》 CSCD 北大核心 2023年第4期1239-1245,1262,共8页
宽度学习系统(BLS)以其良好的学习性能与泛化能力,在高光谱图像(HSI)分类中得到了广泛应用。然而宽度学习系统仅关注各类样本的可分性,忽略了样本之间的相对关系以及所蕴涵的判别信息,在一定程度上限制了宽度学习系统在高光谱图像分类... 宽度学习系统(BLS)以其良好的学习性能与泛化能力,在高光谱图像(HSI)分类中得到了广泛应用。然而宽度学习系统仅关注各类样本的可分性,忽略了样本之间的相对关系以及所蕴涵的判别信息,在一定程度上限制了宽度学习系统在高光谱图像分类任务中的性能。为此,提出一种局部敏感判别的宽度学习系统(LSDBLS)方法。该方法通过引入局部敏感判别分析考虑标记样本的判别信息与数据样本的局部流形结构,通过标记样本构建类内图和类间图来表征数据样本之间的相对关系。在此基础上,将类内图和类间图引入到宽度学习系统的目标函数中,通过最小化类内图以及最大化类间图,使得同类样本尽可能地聚集,不同类的样本尽可能地远离,增强LSDBLS对数据特征的判别能力。通过在三个HSI数据集上的实验结果表明,LSDBLS取得了良好的效果。 展开更多
关键词 宽度学习系统 高光谱图像 类间流形结构 类内流形结构
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联合模态语义相似度修正的无监督跨模态哈希
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作者 陈志奎 蒋昆仑 +2 位作者 钟芳明 原旭 张尧臣 《小型微型计算机系统》 CSCD 北大核心 2023年第10期2204-2211,共8页
基于哈希编码的无监督跨模态检索方法以其存储代价低、检索速度快、无需人工标注信息的优点受到了广泛的关注.最近的方法通过融合各模态的相似度信息构建联合模态相似度矩阵,用以指导哈希编码网络的学习.然而,这些方法未考虑数据特征空... 基于哈希编码的无监督跨模态检索方法以其存储代价低、检索速度快、无需人工标注信息的优点受到了广泛的关注.最近的方法通过融合各模态的相似度信息构建联合模态相似度矩阵,用以指导哈希编码网络的学习.然而,这些方法未考虑数据特征空间的流形结构差异对相似度的影响而引入了噪声降低了模型的检索性能.本文提出了一种基于联合模态语义相似度修正的无监督跨模态哈希方法(JSSR),引入特征空间中的流形结构信息修正相似度矩阵中的噪声信息,同时增强语义相关样本的亲和力,使得生成的哈希码更具判别性和区分度.在典型的公开数据集NUS-WIDE和MIR Flickr上的实验结果表明,JSSR在跨模态检索精度上超越了现有的方法. 展开更多
关键词 跨模态检索 无监督学习 哈希学习 流形结构
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