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MMHCA:Multi-feature representations based on multi-scale hierarchical contextual aggregation for UAV-view geo-localization 被引量:1
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作者 Nanhua CHEN Tai-shan LOU Liangyu ZHAO 《Chinese Journal of Aeronautics》 2025年第6期517-532,共16页
In global navigation satellite system denial environment,cross-view geo-localization based on image retrieval presents an exceedingly critical visual localization solution for Unmanned Aerial Vehicle(UAV)systems.The e... In global navigation satellite system denial environment,cross-view geo-localization based on image retrieval presents an exceedingly critical visual localization solution for Unmanned Aerial Vehicle(UAV)systems.The essence of cross-view geo-localization resides in matching images containing the same geographical targets from disparate platforms,such as UAV-view and satellite-view images.However,images of the same geographical targets may suffer from occlusions and geometric distortions due to variations in the capturing platform,view,and timing.The existing methods predominantly extract features by segmenting feature maps,which overlook the holistic semantic distribution and structural information of objects,resulting in loss of image information.To address these challenges,dilated neighborhood attention Transformer is employed as the feature extraction backbone,and Multi-feature representations based on Multi-scale Hierarchical Contextual Aggregation(MMHCA)is proposed.In the proposed MMHCA method,the multiscale hierarchical contextual aggregation method is utilized to extract contextual information from local to global across various granularity levels,establishing feature associations of contextual information with global and local information in the image.Subsequently,the multi-feature representations method is utilized to obtain rich discriminative feature information,bolstering the robustness of model in scenarios characterized by positional shifts,varying distances,and scale ambiguities.Comprehensive experiments conducted on the extensively utilized University-1652 and SUES-200 benchmarks indicate that the MMHCA method surpasses the existing techniques.showing outstanding results in UAV localization and navigation. 展开更多
关键词 Geo-localization Image retrieval UAV Hierarchical contextual aggregation Multi-feature representations
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The cultures of science quadrant:Scientific representations,practices and conventions in the East and West
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作者 Luke J Buhagiar Stavroula Tsirogianni Gordon Sammut 《Cultures of Science》 2025年第2期140-155,共16页
This paper considers the notions of common sense and interobjectivity to articulate an understanding of how different cultural realities give rise to different construals of scientific phenomena across distinct cultur... This paper considers the notions of common sense and interobjectivity to articulate an understanding of how different cultural realities give rise to different construals of scientific phenomena across distinct cultures. Our main focus in this paper is on the social sciences. We propose a quadrant of different cultural–scientific stances from which the study of social phenomena is possible, based on the emic–etic dimension pertaining to the study of culture from contrasting perspectives. Although the emic–etic distinction is normal y applied in fields within the science of culture, it is proposed here that the distinction is in some ways germane to scientific practice in general, making it amenable for use in a culture of science(CoS) programme. The four perspectives that emerge from the quadrant are illustrated using exemplars. Different aspects of CoS—that is, scientific practice, scientific conventions and representations of science—are then discussed in further detail, including in two tables illustrating points of convergence and divergence between the East and West when it comes to different aspects of CoS. 展开更多
关键词 Science culture EMIC etic interobjectivity common sense culture of science representations CONVENTIONS scientific practice
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Advances in small molecule representations and AI-driven drug research:bridging the gap between theory and application 被引量:1
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作者 Junxi Liu Shan Chang +2 位作者 Qingtian Deng Yulian Ding Yi Pan 《Chinese Journal of Natural Medicines》 2025年第11期1391-1408,共18页
Artificial intelligence(AI)researchers and cheminformatics specialists strive to identify effective drug precursors while optimizing costs and accelerating development processes.Digital molecular representation plays ... Artificial intelligence(AI)researchers and cheminformatics specialists strive to identify effective drug precursors while optimizing costs and accelerating development processes.Digital molecular representation plays a crucial role in achieving this objective by making molecules machine-readable,thereby enhancing the accuracy of molecular prediction tasks and facilitating evidence-based decision making.This study presents a comprehensive review of small molecular representations and AI-driven drug discovery downstream tasks utilizing these representations.The research methodology begins with the compilation of small molecule databases,followed by an analysis of fundamental molecular representations and the models that learn these representations from initial forms,capturing patterns and salient features across extensive chemical spaces.The study then examines various drug discovery downstream tasks,including drug-target interaction(DTI)prediction,drug-target affinity(DTA)prediction,drug property(DP)prediction,and drug generation,all based on learned representations.The analysis concludes by highlighting challenges and opportunities associated with machine learning(ML)methods for molecular representation and improving downstream task performance.Additionally,the representation of small molecules and AI-based downstream tasks demonstrates significant potential in identifying traditional Chinese medicine(TCM)medicinal substances and facilitating TCM target discovery. 展开更多
关键词 Small molecular representation Drug-target interaction prediction Drug-target affinity prediction Drug property prediction De novo drug generation Traditional Chinese medicine
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On the representations of string pairs over virtual field
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作者 TAO Kun FU Chang-Jian 《四川大学学报(自然科学版)》 北大核心 2025年第5期1103-1108,共6页
Let F_(1)be the virtual field consisting of one element and(Q,I)a string pair.In this paper,we study the representations of string pairs over the virtual field F_(1).It is proved that an indecomposable F_(1)-represent... Let F_(1)be the virtual field consisting of one element and(Q,I)a string pair.In this paper,we study the representations of string pairs over the virtual field F_(1).It is proved that an indecomposable F_(1)-representation is either a string representation or a band representation by using the coefficient quivers.It is worth noting that for a given band and a positive integer,there exists a unique band representation up to isomorphism. 展开更多
关键词 string pair string representation band representation
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bell hooks: To Resist Misrepresentations of the Outlaw Culture
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作者 黄春燕 《海外英语》 2012年第4X期3-5,共3页
The thesis summarizes bell hooks' stand and viewpoints as expressed in her book Outlaw Culture:Resisting Representations.In this collection,hooks argues that the outlaw culture,a culture of the marginalized groups... The thesis summarizes bell hooks' stand and viewpoints as expressed in her book Outlaw Culture:Resisting Representations.In this collection,hooks argues that the outlaw culture,a culture of the marginalized groups including black people and women,is either distorted or misinterpreted by the mainstream culture which is a white supremacist patriarchal one.Therefore,she calls for a resistance against the mainstream culture's misrepresentations of the outlaw culture. 展开更多
关键词 BELL HOOKS OUTLAW CULTURE RESIST representations t
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Representations of Co-regular Subsets on Euclidean Spaces 被引量:2
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作者 邱玉文 王莉萍 赵希顺 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第2期252-257,共6页
For the computability of co-regular subsets in metric spaces, the properties of the co-regular subsets and several reasonable representations on co-regular sets have been suggested in this paper. As last, the 'weaker... For the computability of co-regular subsets in metric spaces, the properties of the co-regular subsets and several reasonable representations on co-regular sets have been suggested in this paper. As last, the 'weaker or stronger' relations of these representations have been revealed. 展开更多
关键词 type-2 theory of effectivity COMPUTABILITY computable set representations
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Multipartite State Representations in Multi-mode Fock Space and Their Squeezing Transformations 被引量:1
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作者 YUAN Hong-Chun LI Heng-Mei QI Kai-Guo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期31-34,共4页
We present the continuous state vector of the total coordinate of multi-partlcle and the state vector of their total momentum, respectively, which possess completeness relation in multi-mode Fock space by virtue of th... We present the continuous state vector of the total coordinate of multi-partlcle and the state vector of their total momentum, respectively, which possess completeness relation in multi-mode Fock space by virtue of the integration within an order product (IWOP) technique. We also calculate the transition from classical transformation of variables in the states to quantum unitary operator, deduce a new multi-mode squeezing operator, and discuss its squeezing effect. In progress, it indicates that the IWOP technique provides a convenient way to construct new representation in quantum mechanics. 展开更多
关键词 IWOP technique multipartite state representations squeezing operator
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Enhanced LMI Representations for H2 Performance of Polytopic Uncertain Systems: Continuous-time Case 被引量:1
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作者 Ai-Guo Wu Guang-Ren Duan 《International Journal of Automation and computing》 EI 2006年第3期304-308,共5页
Based on two recent results, several new criteria of H2 performance for continuous-time linear systems are established by introducing two slack matrices. When used in robust analysis of systems with polytopic uncertai... Based on two recent results, several new criteria of H2 performance for continuous-time linear systems are established by introducing two slack matrices. When used in robust analysis of systems with polytopic uncertainties, they can reduce conservatism inherent in the earlier quadratic method and the established parameter-dependent Lyapunov function approach. Two numerical examples are included to illustrate the feasibility and advantage of the proposed representations. 展开更多
关键词 LMI representations H2 performance polytopic uncertainty continuous-time systems
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FREUD-BUTZER-HAHN TYPE QUANTITATIVE THEOREMS FOR PROBABILISTIC REPRESENTATIONS OF(C_0)OPERATOR SEMIGROUPS 被引量:1
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作者 Chen Wenzhong (Xiamen University China)Zhou Mi (Xiamen Fisheries College,China) 《Analysis in Theory and Applications》 1993年第3期1-8,共8页
In this paper,we shall exploit the Freud method in the Classical operator approximation theory to im- prove known quantitative estimalions with an emphasis on Calculah' on the generic constants.
关键词 Th FREUD-BUTZER-HAHN TYPE QUANTITATIVE THEOREMS FOR PROBABILISTIC representations OF C0)OPERATOR SEMIGROUPS
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Finite dimensional irreducible representations of Lie superalgebra D(2,1;α)
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作者 陈曦 杨文力 +1 位作者 丁祥茂 张耀中 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第2期14-28,共15页
This paper focuses on the finite dimensional irreducible representations of Lie superalgebra D(2,1;α).We explicitly construct the finite dimensional representations of the superalgebra D(2,1;α)by using the shift ope... This paper focuses on the finite dimensional irreducible representations of Lie superalgebra D(2,1;α).We explicitly construct the finite dimensional representations of the superalgebra D(2,1;α)by using the shift operator and differential operator representations.Unlike ordinary Lie algebra representation,there are typical and atypical representations for most superalgebras.Therefore,its typical and atypical representation conditions are also given.Our results are expected to be useful for the construction of primary fields of the corresponding current superalgebra of D(2,1;α). 展开更多
关键词 SUPERALGEBRA representations shift operator conformal field theory
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QUASI-PERMUTATION REPRESENTATIONS OF ALTERNATING AND SYMMETRIC GROUPS
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作者 Houshang Behravesh Mohammad Hossein Jafari 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期297-300,共4页
The quantities c(G), q(G) and p(G) for finite groups were defined by H. Behravesh. In this article, these quantities for the alternating group An and the symmetric group Sn are calculated. It is shown that c(G... The quantities c(G), q(G) and p(G) for finite groups were defined by H. Behravesh. In this article, these quantities for the alternating group An and the symmetric group Sn are calculated. It is shown that c(G) = q(G) = p(G) = n,when G = An or Sn. 展开更多
关键词 Quasi-permutation representations alternating groups symmetric groups character theory
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STRONG REPRESENTATIONS OF THE SURVIVAL FUNCTION ESTIMATOR ON INCREASING SETS FOR TRUNCATED AND CENSORED DATA
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作者 孙六全 郑忠国 《Acta Mathematica Scientia》 SCIE CSCD 1999年第3期251-260,共10页
In this paper, based on random left truncated and right censored data, the authors derive strong representations of the cumulative hazard function estimator and the product-limit estimator of the survival function. wh... In this paper, based on random left truncated and right censored data, the authors derive strong representations of the cumulative hazard function estimator and the product-limit estimator of the survival function. which are valid up to a given order statistic of the observations. A precise bound for the errors is obtained which only depends on the index of the last order statistic to be included. 展开更多
关键词 truncated and censored data cumulative hazard function product-limit estimator strong representations
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Graphical representations and worm algorithms for the O(N) spin model
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作者 Longxiang Liu Lei Zhang +1 位作者 Xiaojun Tan Youjin Deng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第11期152-161,共10页
We present a family of graphical representations for the O(N)spin model,where N≥1 represents the spin dimension,and N=1,2,3 corresponds to the Ising,XY and Heisenberg models,respectively.With an integer parameter 0≤... We present a family of graphical representations for the O(N)spin model,where N≥1 represents the spin dimension,and N=1,2,3 corresponds to the Ising,XY and Heisenberg models,respectively.With an integer parameter 0≤ℓ≤N/2,each configuration is the coupling of ℓ copies of subgraphs consisting of directed flows and N−2ℓ copies of subgraphs constructed by undirected loops,which we call the XY and Ising subgraphs,respectively.On each lattice site,the XY subgraphs satisfy the Kirchhoff flow-conservation law and the Ising subgraphs obey the Eulerian bond condition.Then,we formulate worm-type algorithms and simulate the O(N)model on the simple-cubic lattice for N from 2 to 6 at all possibleℓ.It is observed that the worm algorithm has much higher efficiency than the Metropolis method,and,for a given N,the efficiency is an increasing function ofℓ.Besides Monte Carlo simulations,we expect that these graphical representations would provide a convenient basis for the study of the O(N)spin model by other state-of-the-art methods like the tensor network renormalization. 展开更多
关键词 Markov-chain Monte Carlo algorithms continuous spin models graphical representations
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Canonical and Boundary Representations on Rank One Para-Hermitian Spaces
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作者 Anatoli A. Artemov 《Applied Mathematics》 2013年第11期35-40,共6页
This work studies the canonical representations (Berezin representations) for para-Hermitian symmetric spaces of rank one. These spaces are exhausted up to the covering by spaces?G/H?with G = SL(n,R),H = GL(n-1,R)?. F... This work studies the canonical representations (Berezin representations) for para-Hermitian symmetric spaces of rank one. These spaces are exhausted up to the covering by spaces?G/H?with G = SL(n,R),H = GL(n-1,R)?. For Hermitian symmetric spaces G/K, canonical representations were introduced by Berezin and Vershik-Gelfand-Graev. They are unitary with respect to some invariant non-local inner product (the Berezin form). We consider canonical representations in a wider sense: we give up the condition of unitarity and let these representations act on spaces of distributions. For our spaces G/H, the canonical representations turn out to be tensor products of representations of maximal degenerate series and contragredient representations. We decompose the canonical representations into irreducible constituents and decompose boundary representations. 展开更多
关键词 Para-Hermitian Symmetric SPACES Overgroups CANONICAL representations Boundary representations POISSON and Fourier Transforms
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Shell-model representations of the microscopic version of the Bohr-Mottelson collective model
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作者 H G Ganev 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第8期79-90,共12页
The structure of the irreducible collective spaces of the group Sp(12,R),which many-particle nuclear states are classified according to the chain Sp(12,R)⊃U(6)⊃SO(6)⊃SU_(pn)(3)⊗SO(2)⊃SO(3)of the proton-neutron symplec... The structure of the irreducible collective spaces of the group Sp(12,R),which many-particle nuclear states are classified according to the chain Sp(12,R)⊃U(6)⊃SO(6)⊃SU_(pn)(3)⊗SO(2)⊃SO(3)of the proton-neutron symplectic model(PNSM),is considered in detail.This chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr-Mottelson collective model.The construction of the relevant shell-model representations of the Sp(12,R)group along this chain is considered for three nuclei with varying collective properties and from different mass regions.It is shown that the SU_(pn)(3)basis states of the Sp(12,R)representations belonging to the SO(6)irreps with seniorityυ≥υ0,withυ0 denoting the maximal seniority SO(6)irrep contained in the Sp(12,R)bandhead,are always Pauli allowed,but organized in a different way into different SO(6)shells.This is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm operation.Although the SU_(pn)(3)multiplets withinυ<υ0 are not all Pauli forbidden,it is safe to discard them.The results obtained in the present work are important for the practical application of the microscopic version of the Bohr-Mottelson collective model. 展开更多
关键词 microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model Sp(12 R)dynamical algebra shell-model representations
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Transition Dipole, Charge Transfer, and Electron-hole Coherence in Two-photon Absorption: Visualizations with Two Dimensional Site and Three Dimensional Cube Representations
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作者 Yuan-zuo Li Wen-qin Zhang +2 位作者 Xiao-hong Zhao Feng-cai Ma Mao-du Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第5期529-534,I0002,共7页
The developed visualization methods of two dimensional (2D) site and three dimensional (3D) cube representations have been performed to show the orientation of transition dipole, charge transfer, and electron-hole... The developed visualization methods of two dimensional (2D) site and three dimensional (3D) cube representations have been performed to show the orientation of transition dipole, charge transfer, and electron-hole coherence in two-photon absorption (TPA). The 3D cube representations of transition density can reveal visually the orientation and strength of transition dipole moment, and charge different density show the orientation of charge transfer in TPA. The 2D site representation can reveal visually the electron-hole coherence in TPA. The combination of 2D site and 3D cube representations provide clearly inspect into the charge transfer process and the contribution of excited molecular segments for TPA. 展开更多
关键词 2D site and 3D cube representations Charge transfer Transition dipole Two-photon absorption
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Narrative Representations in Adolescents With Learning Difficulties
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作者 Malacrida Marta Provantini Katia Mittino Filippo 《Psychology Research》 2019年第5期203-215,共13页
This research develops from clinical practice. Our aim is to provide a precise description of mental functioning of adolescents with learning difficulties (LDs) in order to improve the knowledge of this kind of proble... This research develops from clinical practice. Our aim is to provide a precise description of mental functioning of adolescents with learning difficulties (LDs) in order to improve the knowledge of this kind of problems and consequently to get better therapeutic approaches. We focus on narrative representations and we study how these adolescents construct and build stories. We assess 40 adolescents through the use of two kind of tests: Thematic Apperception Test (TAT) and Wechsler Intelligence Scale for Children (WISC-III). In addition, we compare this group with another clinical sample of adolescents. In our sample, learning difficulties are not linked to lower cognitive level, but can be understood as a maturational gap. In the narratives of the adolescents with LDs, we find a typical adolescent narrative: In most cases, the protagonist starts from a position of dependence finally reaching a position of greater autonomy. There are significant differences between the males and females in our sample, which suggest a different mode of learning ability and disability for each sex. 展开更多
关键词 adolescents LEARNING DIFFICULTIES NARRATIVE representations
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CANONICAL REPRESENTATIONS AND DEGREE OF FREEDOM FORMULAE OF ORTHOGONAL TENSORS IN N-DIMENSIONAL EUCLIDEAN SPACE
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作者 熊祝华 郑泉水 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第1期93-101,共9页
In this paper, with the help of the eigenvalue properties of orthogonal tensors in n-dimensional Euclidean space and the representations of the orthogonal tensors in 2-dimensional space, the canonical representations ... In this paper, with the help of the eigenvalue properties of orthogonal tensors in n-dimensional Euclidean space and the representations of the orthogonal tensors in 2-dimensional space, the canonical representations of orthogonal tensors in n-dimensional Euclidean space are easily gotten. The paper also gives all the constraint relationships among the principal invariants of arbitrarily given orthogonal tensor by use of Cayley-Hamilton theorem; these results make it possible to solve all the eigenvalues of any orthogonal tensor based on a quite reduced equation of m-th order, where m is the integer part ofn \2. Finally, the formulae of the degree of freedom of orthogonal tensors are given. 展开更多
关键词 CANONICAL representations AND DEGREE OF FREEDOM FORMULAE OF ORTHOGONAL TENSORS IN N-DIMENSIONAL EUCLIDEAN SPACE exp
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Hierarchical Representations Feature Deep Learning for Face Recognition
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作者 Haijun Zhang Yinghui Chen 《Journal of Data Analysis and Information Processing》 2020年第3期195-227,共33页
Most modern face recognition and classification systems mainly rely on hand-crafted image feature descriptors. In this paper, we propose a novel deep learning algorithm combining unsupervised and supervised learning n... Most modern face recognition and classification systems mainly rely on hand-crafted image feature descriptors. In this paper, we propose a novel deep learning algorithm combining unsupervised and supervised learning named deep belief network embedded with Softmax regress (DBNESR) as a natural source for obtaining additional, complementary hierarchical representations, which helps to relieve us from the complicated hand-crafted feature-design step. DBNESR first learns hierarchical representations of feature by greedy layer-wise unsupervised learning in a feed-forward (bottom-up) and back-forward (top-down) manner and then makes more efficient recognition with Softmax regress by supervised learning. As a comparison with the algorithms only based on supervised learning, we again propose and design many kinds of classifiers: BP, HBPNNs, RBF, HRBFNNs, SVM and multiple classification decision fusion classifier (MCDFC)—hybrid HBPNNs-HRBFNNs-SVM classifier. The conducted experiments validate: Firstly, the proposed DBNESR is optimal for face recognition with the highest and most stable recognition rates;second, the algorithm combining unsupervised and supervised learning has better effect than all supervised learning algorithms;third, hybrid neural networks have better effect than single model neural network;fourth, the average recognition rate and variance of these algorithms in order of the largest to the smallest are respectively shown as DBNESR, MCDFC, SVM, HRBFNNs, RBF, HBPNNs, BP and BP, RBF, HBPNNs, HRBFNNs, SVM, MCDFC, DBNESR;at last, it reflects hierarchical representations of feature by DBNESR in terms of its capability of modeling hard artificial intelligent tasks. 展开更多
关键词 Face Recognition UNSUPERVISED Hierarchical representations Hybrid Neural Networks RBM Deep Belief Network Deep Learning
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