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Local spatial properties based image interpolation scheme using SVMs 被引量:2
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作者 Ma Liyong Shen Yi Ma Jiachen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期618-623,共6页
Image interpolation plays an important role in image process applications. A novel support vector machines (SVMs) based interpolation scheme is proposed with increasing the local spatial properties in the source ima... Image interpolation plays an important role in image process applications. A novel support vector machines (SVMs) based interpolation scheme is proposed with increasing the local spatial properties in the source image as SVMs input patterns. After the proper neighbor pixels region is selected, trained support vectors are obtained by training SVMs with local spatial properties that include the average of the neighbor pixels gray values and the gray value variations between neighbor pixels in the selected region. The support vector regression machines are employed to estimate the gray values of unknown pixels with the neighbor pixels and local spatial properties information. Some interpolation experiments show that the proposed scheme is superior to the linear, cubic, neural network and other SVMs based interpolation approaches. 展开更多
关键词 image processing interpolation support vector machines local spatial properties support vectorregression.
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Approach for Obtaining Material Mechanical Properties in Local Region of Structure Based on Accurate Analysis of Micro-indentation Test
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作者 He Xue Jinxuan He +1 位作者 Jianlong Zhang Yuxuan Xue 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第6期147-158,共12页
The hot or cold processing would induce the change and the inhomogeneous of the material mechanical properties in the local processing region of the structure,and it is difficult to obtain the specific mechanical prop... The hot or cold processing would induce the change and the inhomogeneous of the material mechanical properties in the local processing region of the structure,and it is difficult to obtain the specific mechanical properties in these regions by using the traditional material tensile test.To accurately get actual material mechanical properties in the local region of structure,a micro-indentation test system incorporated by an electronic universal material test device has been established.An indenter displacement sensor and a group of special micro-indenter assemblies are estab-lished.A numerical indentation inversion analysis method by using ABAQUS software is also proposed in this study.Based on the above test system and analysis platform,an approach to obtaining material mechanical properties in the local region of structures is proposed and established.The ball indentation test is performed and combined with the energy method by using various changed mechanical properties of 316L austenitic stainless steel under differ-ent elongations.The investigated results indicate that the material mechanical properties and the micro-indentation morphological changes have evidently relevance.Compared with the tensile test results,the deviations of material mechanical parameters,such as hardness H,the hardening exponent n,the yield strength σy and others are within 5%obtained through the indentation test and the finite element analysis.It provides an effective and convenient method for obtaining the actual material mechanical properties in the local processing region of the structure. 展开更多
关键词 Structural integrity assessment Micro-indentation test Numerical testing inversion analysis local material mechanical property
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Locally Asymptotic-norming Property and Kadec Property 被引量:1
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作者 王建华 《Northeastern Mathematical Journal》 CSCD 2002年第2期167-174,共8页
In this paper we study the three new asymptotic-norming properties which are called locally asymptotic-norming property k,k=Ⅰ, Ⅱ,Ⅲ, and discuss the relationship between the locally asymptotic-norming property and t... In this paper we study the three new asymptotic-norming properties which are called locally asymptotic-norming property k,k=Ⅰ, Ⅱ,Ⅲ, and discuss the relationship between the locally asymptotic-norming property and the Kadec Property. 展开更多
关键词 asymptotic-norming property Kadec property weak topology locally asymptotic-norming property near convexity
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Almost Fixed Points and Fixed Points of Upper [Lower] Semicontinuous Multimap on Locally G-convex Spaces 被引量:3
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作者 朴勇杰 《Northeastern Mathematical Journal》 CSCD 2005年第4期391-396,共6页
In this paper, we use the well known KKM type theorem for generalized convex spaces due to Park (Elements of the KKM theory for generalized convex spaces, Korean J. Comp. Appl. Math., 7(2000), 1-28) to obtain an a... In this paper, we use the well known KKM type theorem for generalized convex spaces due to Park (Elements of the KKM theory for generalized convex spaces, Korean J. Comp. Appl. Math., 7(2000), 1-28) to obtain an almost fixed point theorem for upper [resp., lower] semicontinuous multimaps in locally G-convex spaces, and then give a fixed point theorem for upper semicontinuous multimap with closed Γ-convex values. 展开更多
关键词 G-convex space upper [lower] semicontinuous locally G-convex space ahnost fixed point property ahnost Γ-convex
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ON SOME PROPERTIES OF LIENARD SYSTEMS
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作者 HAN Mao-an(韩茂安) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第4期454-462,共9页
Some sharp sufficient conditions for generalized Lienard systems to have positive or negative semi-orbits which do not cross the vertical isocline are given. Applications of the main results to some polynomial systems... Some sharp sufficient conditions for generalized Lienard systems to have positive or negative semi-orbits which do not cross the vertical isocline are given. Applications of the main results to some polynomial systems are also presented. 展开更多
关键词 Lienard system local property global property
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QUASI_EQUILIBRIUM PROBLEMS IN NONCOMPACT GENERALIZED CONVEX SPACES 被引量:3
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第6期637-644,共8页
By applying a new fixed point theorem due to the author, some new equilibrium existence theorems of quasi-equilibrium problems are proved in noncompact generalized convex spaces. These theorems improve and generalize ... By applying a new fixed point theorem due to the author, some new equilibrium existence theorems of quasi-equilibrium problems are proved in noncompact generalized convex spaces. These theorems improve and generalize a number of important known results in recent literature. 展开更多
关键词 fixed point quasi-equilibrium problem compactly local intersection property generalized convex space
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Unveiling the Residual Stresses,Local Micromechanical Properties and Crystallographic Texture in a Ti-6Al-4V Weld Joint 被引量:3
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作者 B.Mehdi R.Badji +5 位作者 V.Ji B.Alili D.Bradai W.Bedjaoui F.Deschaux-Beaume F.Brisset 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2021年第7期997-1006,共10页
In this work,the micromechanical properties,crystallographic texture,welding residual stresses and their evolution after plastic strain were investigated in a Ti-6Al-4V alloy tungsten inert gas weld joint.It was found... In this work,the micromechanical properties,crystallographic texture,welding residual stresses and their evolution after plastic strain were investigated in a Ti-6Al-4V alloy tungsten inert gas weld joint.It was found that the welding process affected the Young modulus and microhardness values in bothαandβphases in the different regions of the weld joint.The highest microhardness and Young modulus values of a phase were recorded in the heat-affected zone,whereas the highest values of these characteristics for theβphase were found in the fusion zone(FZ).The change in the micro mechanical properties was accompanied by a change in the crystallographic texture components of the dominant a phase from(0001)<10-10>and(11-20)<10-10>components in the base material to(10-10)<11-20>and(11-20)<3-302>components in the FZ.The introduction of tensile testing resulted in a continuous stress relaxation and improved the weld joint performances. 展开更多
关键词 Ti-6Al-4 V Tungsten inert gas(TIG)weld Residual stress local mechanical properties Crystallographic texture
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Local melting mechanism and its effects on mechanical properties of friction spot welded joint for Al-Zn-Mg-Cu alloy 被引量:4
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作者 Yunqiang Zhao Chungui Wang +2 位作者 Jizhong Li Jinhong Tan Chunlin Dong 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2018年第1期185-191,共7页
Local melting and the eutectic film and liquation crack formation mechanisms during friction spot weld- ing (FSpW) of Al-Zn-Mg-Cu alloy were studied by both experiment and finite element simulation. Their effects on... Local melting and the eutectic film and liquation crack formation mechanisms during friction spot weld- ing (FSpW) of Al-Zn-Mg-Cu alloy were studied by both experiment and finite element simulation. Their effects on mechanical properties of the joint were examined. When the welding heat input was high, the peak temperature in the stir zone was higher than the incipient melting temperature of the Al-Zn-Mg-Cu alloy. This resulted in local melting along the grain boundaries in this zone. In the retreating stage of the welding process, the formed liquid phase was driven by the flowing plastic material and redistributed as a "U-shaped" line in the stir zone. In the following cooling stage, this liquid phase transformed into eutectic films and liquation cracks. As a result, a new characteristic of"U" line that consisted of eutectic films and liquation cracks is formed in the FSpWjoin. This "U" line was located in the high stress region when the FSpW joint was loaded, thus it was adverse to the mechanical properties of the FSpW joint. During tensile shear tests, the "U" line became a preferred crack propagation path, resulting in the occurrence of brittle fracture. 展开更多
关键词 Friction spot welding Numerical simulation local melting Liquation crack Mechanical property
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Reliable iris localization using integral projection function and 2D-shape properties
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作者 Farmanullah Jan Imran Usman Shahrukh Agha 《Chinese Optics Letters》 SCIE EI CAS CSCD 2012年第11期50-55,共6页
Iris recognition technology recognizes a human based on his/her iris pattern. However, the accuracy of the iris recognition technology depends on accurate iris localization. Localizing a pupil region in the presence o... Iris recognition technology recognizes a human based on his/her iris pattern. However, the accuracy of the iris recognition technology depends on accurate iris localization. Localizing a pupil region in the presence of other low-intensity regions, such as hairs, eyebrows, and eyelashes, is a challenging task. This study proposes an iris localization technique that includes a localizing pupillary boundary in a sub-image by using an integral projection function and two-dimensional shape properties (e.g., area, geometry, and circularity). The limbic boundary is localized using gradients and an error distance transform, and the boundary is regularized with active contours. Experimental results obtained from public databases show the superiority of the Drooosed techniaue over contemporary methods. 展开更多
关键词 Reliable iris localization using integral projection function and 2D-shape properties ROI
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Non-Hermitian topological Anderson insulators 被引量:4
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作者 Dan-Wei Zhang Ling-Zhi Tang +2 位作者 Li-Jun Lang Hui Yan Shi-Liang Zhu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2020年第6期2-12,共11页
Non-Hermitian systems can exhibit exotic topological and localization properties.Here we elucidate the non-Hermitian effects on disordered topological systems using a nonreciprocal disordered Su-Schrieffer-Heeger mode... Non-Hermitian systems can exhibit exotic topological and localization properties.Here we elucidate the non-Hermitian effects on disordered topological systems using a nonreciprocal disordered Su-Schrieffer-Heeger model.We show that the non-Hermiticity can enhance the topological phase against disorders by increasing bulk gaps.Moreover,we uncover a topological phase which emerges under both moderate non-Hermiticity and disorders,and is characterized by localized insulating bulk states with a disorder-averaged winding number and zero-energy edge modes.Such topological phases induced by the combination of non-Hermiticity and disorders are dubbed non-Hermitian topological Anderson insulators.We reveal that the system has unique non-monotonous localization behavior and the topological transition is accompanied by an Anderson transition.These properties are general in other non-Hermitian models. 展开更多
关键词 topological insulators non-Hermitian systems localization properties
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Coincidence Theorems with Applications to Minimax Inequalities,Section Theorem,Best Approximation and Multiobjective Games in Topological Spaces 被引量:2
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作者 Lei DENG Ming Ge YANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第6期1809-1818,共10页
Some new coincidence theorems involving admissible set-valued mappings are proved in general noncompact topological spaces. As applications, some new minimax inequalities, section theorem, best approximation theorem, ... Some new coincidence theorems involving admissible set-valued mappings are proved in general noncompact topological spaces. As applications, some new minimax inequalities, section theorem, best approximation theorem, existence theorems of weighted Nash equilibria and Pareto equilibria for multiobjective games are given in general topological spaces. 展开更多
关键词 admissible set-valued mapping generalized R-KKM mapping transfer compactly openvalued compactly local intersection property multiobjective game
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A Characterization for a Complete Random Normed Module to Be Mean Ergodic 被引量:1
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作者 Xia ZHANG Ming LIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2017年第7期899-910,共12页
In this paper, we first study the mean ergodicity of random linear operators using some techniques of measure theory and L;-convex analysis. Then, based on this, we give a characterization for a complete random normed... In this paper, we first study the mean ergodicity of random linear operators using some techniques of measure theory and L;-convex analysis. Then, based on this, we give a characterization for a complete random normed module to be mean ergodic. 展开更多
关键词 Random normed module mean ergodic random linear operator the local property
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On Tamed Almost Complex Four‑Manifolds 被引量:1
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作者 Qiang Tan Hongyu Wang +1 位作者 Jiuru Zhou Peng Zhu 《Peking Mathematical Journal》 2022年第1期37-152,共116页
This paper proves that on any tamed closed almost complex four-manifold(M,J)whose dimension of J-anti-invariant cohomology is equal to the self-dual second Betti number minus one,there exists a new symplectic form com... This paper proves that on any tamed closed almost complex four-manifold(M,J)whose dimension of J-anti-invariant cohomology is equal to the self-dual second Betti number minus one,there exists a new symplectic form compatible with the given almost complex structure J.In particular,if the self-dual second Betti number is one,we give an affirmative answer to a question of Donaldson for tamed closed almost complex four-manifolds.Our approach is along the lines used by Buchdahl to give a unified proof of the Kodaira conjecture. 展开更多
关键词 ω-Tame(compatible)almost complex structure J-Anti-invariant cohomology Positive(1 1)current local symplectic property J-Holomorphic curve
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Exact mobility edges and topological phase transition in two-dimensional non-Hermitian quasicrystals
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作者 Zhi-Hao Xu Xu Xia Shu Chen 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2022年第2期82-90,共9页
The emergence of the mobility edge(ME)has been recognized as an important characteristic of Anderson localization.The difficulty in understanding the physics of the MEs in three-dimensional(3 D)systems from a microsco... The emergence of the mobility edge(ME)has been recognized as an important characteristic of Anderson localization.The difficulty in understanding the physics of the MEs in three-dimensional(3 D)systems from a microscopic image encourages the development of models in lower-dimensional systems that have exact MEs.While most of the previous studies are concerned with one-dimensional(1 D)quasiperiodic systems,the analytic results that allow for an accurate understanding of two-dimensional(2 D)cases are rare.In this work,we disclose an exactly solvable 2 D quasicrystal model with parity-time(PT)symmetry displaying exact MEs.In the thermodynamic limit,we unveil that the extended-localized transition point,observed at the PT symmetry breaking point,is topologically characterized by a hidden winding number defined in the dual space.The coupling waveguide platform can be used to realize the 2 D non-Hermitian quasicrystal model,and the excitation dynamics can be used to detect the localization features. 展开更多
关键词 QUASICRYSTALS mobility edges non-Hermitian systems localization properties
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A NOTE ON BEURLING-DENY FORMULAE IN INFINITE DIMENSIONAL SPACES 被引量:1
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作者 董昭 马志明 孙玮 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1997年第4期353-361,共6页
The uniqueness of the Beurling-Deny first formula in quasi-regular Dirichlet spaces is verified in terms of the strictly strong local property. An extension of the Beurling-Deny second formula is obtained in infinite... The uniqueness of the Beurling-Deny first formula in quasi-regular Dirichlet spaces is verified in terms of the strictly strong local property. An extension of the Beurling-Deny second formula is obtained in infinite dimensional spaces. 展开更多
关键词 Quasi-regular Dirichlet form Beurling-Deny formulae strictly strong local property
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