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Depth-Guided Vision Transformer With Normalizing Flows for Monocular 3D Object Detection
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作者 Cong Pan Junran Peng Zhaoxiang Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期673-689,共17页
Monocular 3D object detection is challenging due to the lack of accurate depth information.Some methods estimate the pixel-wise depth maps from off-the-shelf depth estimators and then use them as an additional input t... Monocular 3D object detection is challenging due to the lack of accurate depth information.Some methods estimate the pixel-wise depth maps from off-the-shelf depth estimators and then use them as an additional input to augment the RGB images.Depth-based methods attempt to convert estimated depth maps to pseudo-LiDAR and then use LiDAR-based object detectors or focus on the perspective of image and depth fusion learning.However,they demonstrate limited performance and efficiency as a result of depth inaccuracy and complex fusion mode with convolutions.Different from these approaches,our proposed depth-guided vision transformer with a normalizing flows(NF-DVT)network uses normalizing flows to build priors in depth maps to achieve more accurate depth information.Then we develop a novel Swin-Transformer-based backbone with a fusion module to process RGB image patches and depth map patches with two separate branches and fuse them using cross-attention to exchange information with each other.Furthermore,with the help of pixel-wise relative depth values in depth maps,we develop new relative position embeddings in the cross-attention mechanism to capture more accurate sequence ordering of input tokens.Our method is the first Swin-Transformer-based backbone architecture for monocular 3D object detection.The experimental results on the KITTI and the challenging Waymo Open datasets show the effectiveness of our proposed method and superior performance over previous counterparts. 展开更多
关键词 Monocular 3D object detection normalizing flows Swin Transformer
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A Normalizing Flow-Based Bidirectional Mapping Residual Network for Unsupervised Defect Detection
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作者 Lanyao Zhang Shichao Kan +3 位作者 Yigang Cen Xiaoling Chen Linna Zhang Yansen Huang 《Computers, Materials & Continua》 SCIE EI 2024年第2期1631-1648,共18页
Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be improved.Specifically,approaches using normalizing flows can accurately ... Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be improved.Specifically,approaches using normalizing flows can accurately evaluate sample distributions,mapping normal features to the normal distribution and anomalous features outside it.Consequently,this paper proposes a Normalizing Flow-based Bidirectional Mapping Residual Network(NF-BMR).It utilizes pre-trained Convolutional Neural Networks(CNN)and normalizing flows to construct discriminative source and target domain feature spaces.Additionally,to better learn feature information in both domain spaces,we propose the Bidirectional Mapping Residual Network(BMR),which maps sample features to these two spaces for anomaly detection.The two detection spaces effectively complement each other’s deficiencies and provide a comprehensive feature evaluation from two perspectives,which leads to the improvement of detection performance.Comparative experimental results on the MVTec AD and DAGM datasets against the Bidirectional Pre-trained Feature Mapping Network(B-PFM)and other state-of-the-art methods demonstrate that the proposed approach achieves superior performance.On the MVTec AD dataset,NF-BMR achieves an average AUROC of 98.7%for all 15 categories.Especially,it achieves 100%optimal detection performance in five categories.On the DAGM dataset,the average AUROC across ten categories is 98.7%,which is very close to supervised methods. 展开更多
关键词 Anomaly detection normalizing flow source domain feature space target domain feature space bidirectional mapping residual network
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Effect of normalizing cooling process on microstructure and precipitates in low-temperature silicon steel 被引量:7
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作者 李慧 冯运莉 +2 位作者 宋孟 梁精龙 苍大强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期770-776,共7页
Microstructure, precipitate and magnetic characteristic of fmal products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared wi... Microstructure, precipitate and magnetic characteristic of fmal products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared with the hot-rolled plate by optical microscopy (OM), transmission electron microscopy (TEM), and energy dispersive spectrometry (EDS). The results show that, the surface microstructure is uniform, the proportion of recrystallization in matrix increases, and the banding textures are narrowed; the precipitates, whose quantity in normalized plate is more than that in hot-rolled plate greatly, are mainly A1N, MnS, composite precipitates (Cu,Mn)S and so on. Normalizing technology with a temperature of 1120 ℃, holding for 3 min, and a two-stage cooling is a most advantaged method to obtain oriented silicon steel with sharper Goss texture and higher magnetic properties, owing to the uniform surface microstructures and the obvious inhomogeneity of microstructures along the thickness. The normalizing technology with the two-stage cooling is the optimum process, which can generate more fine precipitates dispersed over the matrix, and be beneficial for finished products to get higher magnetic properties. 展开更多
关键词 low temperature grain-oriented silicon steel normalizing cooling process MICROSTRUCTURE PRECIPITATE magnetic property
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Comparison of up ladder type and terraced type normalizing heat treatments of heavy cylinder 被引量:1
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作者 孙建亮 彭艳 +1 位作者 邱丑武 张永振 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第11期2777-2783,共7页
Because of the mixed grain and coarse grain structure, the long heat treatment cycle and large energy conservation in the heavy cylinder heat treatment process, the up ladder type and terraced type normalizing heat tr... Because of the mixed grain and coarse grain structure, the long heat treatment cycle and large energy conservation in the heavy cylinder heat treatment process, the up ladder type and terraced type normalizing heat treatment of heavy cylinder after rolling were put forward. The microstructure and mechanical properties of 2.25Cr1Mo0.25 V steel after the up ladder type normalizing, terraced type normalizing and isothermal type normalizing were studied. Experimental results show that: 1) For the grain refinement, the twice terraced type normalizing is better than the up ladder type and isothermal type normalizing, and the average grain size is 18 μm; 2) The yield strength, tensile strength and-30℃ charpy impact energy after twice terraced type normalizing are 681 MPa, 768 MPa and 181 J, respectively, and the mechanical properties are better than those of the up ladder type and isothermal type normalizing; 3) Compared with the isothermal type normalizing, the holding time of terraced type normalizing can be shortened by 30%, which greatly reduces the energy consumption. 展开更多
关键词 heavy cylinder terraced type normalizing up ladder type normalizing mechanical properties
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Effect of Normalizing and Hardening on Mechanical Properties of Spring 被引量:1
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作者 O. R. Adetunji P. O. Aiyedun +1 位作者 S. O. Ismaila M. J. Alao 《Journal of Minerals and Materials Characterization and Engineering》 2012年第8期832-835,共4页
This study was carried out to investigate the effect of heat treatment (Normalizing and Hardening) on the mechanical properties of springs. The springs were made from mild steel rod having a diameter of 6 mm, a total ... This study was carried out to investigate the effect of heat treatment (Normalizing and Hardening) on the mechanical properties of springs. The springs were made from mild steel rod having a diameter of 6 mm, a total of 15 springs were made. The springs were then subjected to various heat treatment processes which included;normalizing, hardening and tempering. The heat treated springs were then subjected to various test in other to determine their mechanical properties, these included;impact toughness test, hardness test and tension test. The normalized spring had more strength, was harder and was much tougher than both the annealed and as received springs. The water quenched springs were the hardest of all the heat treated springs, were very brittle and had the lowest percentage elongation. Their strength was also lower than that of the normalized and as received springs. The water quenched and tempered springs had better mechanical properties required for spring making, they had the optimum combination of hardness, strength and toughness when compared with the other heat treated springs. 展开更多
关键词 normalizing HARDENING TEMPERING Impact TOUGHNESS Tension SPRING
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New formulas for normalizing photon-added(-subtracted) two-mode squeezed thermal states 被引量:1
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作者 胡利云 范洪义 张智明 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期312-316,共5页
For the first time,we derive the compact forms of normalization factors for photon-added(-subtracted) two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of o... For the first time,we derive the compact forms of normalization factors for photon-added(-subtracted) two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of operators(IWOP) technique.It is found that these two factors are related to the Jacobi polynomials.In addition,some new relationships for Jacobi polynomials are presented. 展开更多
关键词 two-mode squeezed thermal states normalIZATION photon addition and subtraction integration within an ordered product of operators technique
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OpenNAU:An open-source platform for normalizing,analyzing,and visualizing cancer untargeted metabolomics data 被引量:1
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作者 Qingrong Sun Qingqing Xu +3 位作者 Majie Wang Yongcheng Wang Dandan Zhang Maode Lai 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2023年第5期550-562,共13页
Objective:As an important part of metabolomics analysis,untargeted metabolomics has become a powerful tool in the study of tumor mechanisms and the discovery of metabolic markers with high-throughput spectrometric dat... Objective:As an important part of metabolomics analysis,untargeted metabolomics has become a powerful tool in the study of tumor mechanisms and the discovery of metabolic markers with high-throughput spectrometric data which also poses great challenges to data analysis,from the extraction of raw data to the identification of differential metabolites.To date,a large number of analytical tools and processes have been developed and constructed to serve untargeted metabolomics research.The different selection of analytical tools and parameter settings lead to varied results of untargeted metabolomics data.Our goal is to establish an easily operated platform and obtain a repeatable analysis result.Methods:We used the R language basic environment to construct the preprocessing system of the original data and the LAMP(Linux+Apache+MySQL+PHP)architecture to build a cloud mass spectrum data analysis system.Results:An open-source analysis software for untargeted metabolomics data(openNAU)was constructed.It includes the extraction of raw mass data and quality control for the identification of differential metabolic ion peaks.A reference metabolomics database based on public databases was also constructed.Conclusions:A complete analysis system platform for untargeted metabolomics was established.This platform provides a complete template interface for the addition and updating of the analysis process,so we can finish complex analyses of untargeted metabolomics with simple human-computer interactions.The source code can be downloaded from https://github.com/zjuRong/openNAU. 展开更多
关键词 Untargeted metabolomics LAMP architecture shiny normalIZATION reference metabolomics
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Normalizing Book Citations in Google Scholar: A Hybrid Cited-side Citing-side Method
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作者 John Mingers Eren Kaymaz 《Journal of Data and Information Science》 CSCD 2019年第2期19-35,共17页
Purpose: To design and test a method for normalizing book citations in Google Scholar.Design/methodology/approach: A hybrid citing-side, cited-side normalization method was developed and this was tested on a sample of... Purpose: To design and test a method for normalizing book citations in Google Scholar.Design/methodology/approach: A hybrid citing-side, cited-side normalization method was developed and this was tested on a sample of 285 research monographs. The results were analyzed and conclusions drawn.Findings: The method was technically feasible but required extensive manual intervention because of the poor quality of the Google Scholar data. Research limitations: The sample of books was limited and also all were from one discipline —business and management. Also, the method has only been tested on Google Scholar, it would be useful to test it on Web of Science or Scopus.Practical limitations: Google Scholar is a poor source of data although it does cover a much wider range citation sources that other databases. Originality/value: This is the first method that has been developed specifically for normalizing books which have so far not been able to be normalized. 展开更多
关键词 Google SCHOLAR BOOK CITATIONS normalIZATION Research evaluation
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Robust adaptive output stabilization using dynamic normalizing signal
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作者 Haixia SU Xuejun XIE Haikuan LIU 《控制理论与应用(英文版)》 EI 2007年第1期89-93,共5页
For a class of nonlinear systems with dynamic uncertainties, robust adaptive stabilization problem is considered in this paper. Firstly, by introducing an observer, an augmented system is obtained. Based on the system... For a class of nonlinear systems with dynamic uncertainties, robust adaptive stabilization problem is considered in this paper. Firstly, by introducing an observer, an augmented system is obtained. Based on the system, we construct an exp-ISpS Lyapunov function for the unmodeled dynamics, prove that the unmodeled dynamics is exp-ISpS, and then obtain a dynamic normalizing signal to counteract the dynamic disturbances. By the backstepping technique, an adaptive controller is given, it is proved that all the signals in the adaptive control system are globally uniformly ultimately bounded, and the output can be regulated to the origin with any prescribed accuracy. A simulation example further demonstrates the efficiency of the control scheme. 展开更多
关键词 Unmodeled dynamics Exp-ISpS Dynamic normalizing signal BACKSTEPPING Adaptive control
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Cyclic shear behavior of en-echelon joints under constant normal stiffness conditions 被引量:1
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作者 Bin Wang Yujing Jiang +3 位作者 Qiangyong Zhang Hongbin Chen Richeng Liu Yuanchao Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3419-3436,共18页
To reveal the mechanism of shear failure of en-echelon joints under cyclic loading,such as during earthquakes,we conducted a series of cyclic shear tests of en-echelon joints under constant normal stiffness(CNS)condit... To reveal the mechanism of shear failure of en-echelon joints under cyclic loading,such as during earthquakes,we conducted a series of cyclic shear tests of en-echelon joints under constant normal stiffness(CNS)conditions.We analyzed the evolution of shear stress,normal stress,stress path,dilatancy characteristics,and friction coefficient and revealed the failure mechanisms of en-echelon joints at different angles.The results show that the cyclic shear behavior of the en-echelon joints is closely related to the joint angle,with the shear strength at a positive angle exceeding that at a negative angle during shear cycles.As the number of cycles increases,the shear strength decreases rapidly,and the difference between the varying angles gradually decreases.Dilation occurs in the early shear cycles(1 and 2),while contraction is the main feature in later cycles(310).The friction coefficient decreases with the number of cycles and exhibits a more significant sensitivity to joint angles than shear cycles.The joint angle determines the asperities on the rupture surfaces and the block size,and thus determines the subsequent shear failure mode(block crushing and asperity degradation).At positive angles,block size is more greater and asperities on the rupture surface are smaller than at nonpositive angles.Therefore,the cyclic shear behavior is controlled by block crushing at positive angles and asperity degradation at negative angles. 展开更多
关键词 En-echelon joint Cyclic shear tests Shear stress normal displacement Constant normal stiffness(CNS)
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Performance Study of an FFH/BFSK Self-Normalizing Receiver with Multitone Jamming's Frequency Offsets
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作者 Chao Wei Yu-Fan Cheng 《Journal of Electronic Science and Technology》 CAS 2010年第2期97-102,共6页
This study investigates how frequency offsets of multitone jamming affect the fast frequencyhopped binary frequency shift keying (FFH/BFSK) self-normalizing (SNZ) receiver under additive white Gaussian noise (AWG... This study investigates how frequency offsets of multitone jamming affect the fast frequencyhopped binary frequency shift keying (FFH/BFSK) self-normalizing (SNZ) receiver under additive white Gaussian noise (AWGN). The average bit-error-rate (BER) expressions of the FFH/BFSK SNZ receiver and the average BER expressions of an FFH/BFSK spread-spectrum (SS) communication system with frequency offsets of multitone jamming for the sake of understanding the simulation results better. Simulation results show that BER performance of the FFH/BFSK SNZ receiver with diversity under the worst case multitone jamming (MTJ) and AWGN suffers from multitone jamming's frequency offsets when the jamming power is moderate, which is validated by several simulations with different frequency offsets configured in multitone jamming. Therefore, an FFH/BFSK SNZ receiver under multitone jamming can be combated with the help of frequency offsets of multitone jamming. 展开更多
关键词 Index Terror. Combatting fast frequency hopping multitone jamming offsets of frequency self- normalizing receiver.
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Unveiling the silent link:Normal-tension glaucoma's enigmatic bond with cardiac blood flow 被引量:1
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作者 Prasanna Venkatesh Ramesh Arvind Kumar Morya +5 位作者 Ajanya K Aradhya Pavithra Pannerselvam Sai Thaejesvi Gopalakrishnan Shruthy Vaishali Ramesh Aji Kunnath Devadas Navaneeth Krishna 《World Journal of Cardiology》 2024年第1期10-15,共6页
This comprehensive review embarks on a captivating journey into the complex relationship between cardiology and normal-tension glaucoma(NTG),a condition that continues to baffle clinicians and researchers alike.NTG,ch... This comprehensive review embarks on a captivating journey into the complex relationship between cardiology and normal-tension glaucoma(NTG),a condition that continues to baffle clinicians and researchers alike.NTG,characterized by optic nerve damage and visual field loss despite normal intraocular pressure,has long puzzled clinicians.One emerging perspective suggests that alterations in ocular blood flow,particularly within the optic nerve head,may play a pivotal role in its pathogenesis.While NTG shares commonalities with its high-tension counterpart,its unique pathogenesis and potential ties to cardiovascular health make it a fascinating subject of exploration.It navigates through the complex web of vascular dysregulation,blood pressure and perfusion pressure,neurovascular coupling,and oxidative stress,seeking to uncover the hidden threads that tie the heart and eyes together in NTG.This review explores into the intricate mechanisms connecting cardiovascular factors to NTG,shedding light on how cardiac dynamics can influence ocular health,particularly in cases where intraocular pressure remains within the normal range.NTG's enigmatic nature,often characterized by seemingly contradictory risk factors and clinical profiles,underscores the need for a holistic approach to patient care.Drawing parallels to cardiac health,we examine into the shared vascular terrain connecting the heart and the eyes.Cardiovascular factors,including systemic blood flow,endothelial dysfunction,and microcirculatory anomalies,may exert a profound influence on ocular perfusion,impacting the delicate balance within the optic nerve head.By elucidating the subtle clues and potential associations between cardiology and NTG,this review invites clinicians to consider a broader perspective in their evaluation and management of this elusive condition.As the understanding of these connections evolves,so too may the prospects for early diagnosis and tailored interventions,ultimately enhancing the quality of life for those living with NTG. 展开更多
关键词 normal tension glaucoma Vascular dysregulation Ocular blood flow Blood pressure Perfusion pressure Oxidative stress
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Normalizing Relationships
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《ChinAfrica》 2016年第4期2-2,共1页
AS diplomatic relations were restored between China and the Islamic Republic of the Gambia in March,China’s Foreign Minister Wang Yi called it a“historic moment”for the two countries.Wang met with his Gambian count... AS diplomatic relations were restored between China and the Islamic Republic of the Gambia in March,China’s Foreign Minister Wang Yi called it a“historic moment”for the two countries.Wang met with his Gambian counterpart Neneh Mac Douall-Gaye in Beijing to sign a joint communique on March 17. 展开更多
关键词 MAC normalizing Relationships
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Extraction of Acoustic Normal Mode Depth Functions Using Range-Difference Method with Vertical Linear Array Data
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作者 GAO Siyu LI Weilu +2 位作者 ZHANG Yinquan LI Xiaolei WANG Ning 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期871-882,共12页
Data-derived normal mode extraction is an effective method for extracting normal mode depth functions in the absence of marine environmental data.However,when the corresponding singular vectors become nonunique when t... Data-derived normal mode extraction is an effective method for extracting normal mode depth functions in the absence of marine environmental data.However,when the corresponding singular vectors become nonunique when two or more singular values obtained from the cross-spectral density matrix diagonalization are nearly equal,this results in unsatisfactory extraction outcomes for the normal mode depth functions.To address this issue,we introduced in this paper a range-difference singular value decomposition method for the extraction of normal mode depth functions.We performed the mode extraction by conducting singular value decomposition on the individual frequency components of the signal's cross-spectral density matrix.This was achieved by using pressure and its range-difference matrices constructed from vertical line array data.The proposed method was validated using simulated data.In addition,modes were successfully extracted from ambient noise. 展开更多
关键词 range difference depth function extraction normal mode
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NORMALIZED SOLUTIONS FOR THE GENERAL KIRCHHOFF TYPE EQUATIONS
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作者 Wenmin LIU Xuexiu ZHONG Jinfang ZHOU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1886-1902,共17页
In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈R×H^(1)(R^(N))to the general Kirchhoff problem-M■,satisfying the normalization constrain... In the present paper,we prove the existence,non-existence and multiplicity of positive normalized solutions(λ_(c),u_(c))∈R×H^(1)(R^(N))to the general Kirchhoff problem-M■,satisfying the normalization constraint f_(R)^N u^2dx=c,where M∈C([0,∞))is a given function satisfying some suitable assumptions.Our argument is not by the classical variational method,but by a global branch approach developed by Jeanjean et al.[J Math Pures Appl,2024,183:44–75]and a direct correspondence,so we can handle in a unified way the nonlinearities g(s),which are either mass subcritical,mass critical or mass supercritical. 展开更多
关键词 normalized solution Kirchhoff type equations general nonlinearities asymptotic behavior
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Schur Forms and Normal-Nilpotent Decompositions
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作者 LI Zhen 《应用数学和力学》 CSCD 北大核心 2024年第9期1200-1211,共12页
Real and complex Schur forms have been receiving increasing attention from the fluid mechanics community recently,especially related to vortices and turbulence.Several decompositions of the velocity gradient tensor,su... Real and complex Schur forms have been receiving increasing attention from the fluid mechanics community recently,especially related to vortices and turbulence.Several decompositions of the velocity gradient tensor,such as the triple decomposition of motion(TDM)and normal-nilpotent decomposition(NND),have been proposed to analyze the local motions of fluid elements.However,due to the existence of different types and non-uniqueness of Schur forms,as well as various possible definitions of NNDs,confusion has spread widely and is harming the research.This work aims to clean up this confusion.To this end,the complex and real Schur forms are derived constructively from the very basics,with special consideration for their non-uniqueness.Conditions of uniqueness are proposed.After a general discussion of normality and nilpotency,a complex NND and several real NNDs as well as normal-nonnormal decompositions are constructed,with a brief comparison of complex and real decompositions.Based on that,several confusing points are clarified,such as the distinction between NND and TDM,and the intrinsic gap between complex and real NNDs.Besides,the author proposes to extend the real block Schur form and its corresponding NNDs for the complex eigenvalue case to the real eigenvalue case.But their justification is left to further investigations. 展开更多
关键词 Schur form normal matrix nilpotent matrix tensor decomposition vortex identification
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NORMALITY AND THE NUMBER OF ZEROS
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作者 WANG Guang-sheng WEI Dong-mei XU Yan 《数学杂志》 2024年第5期377-382,共6页
In this paper,we study normal families of meromorphic functions.By using the idea in[11],we obtain some normality criteria for families of meromorphic functions that concern the number of zeros of the differential pol... In this paper,we study normal families of meromorphic functions.By using the idea in[11],we obtain some normality criteria for families of meromorphic functions that concern the number of zeros of the differential polynomial,which extends the related result of Li,and Chen et al..An example is given to show that the hypothesis on the zeros of a(z)is necessary. 展开更多
关键词 Meromorphic function normal family differential polynomial ZERO
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Shear mechanical properties and frictional sliding responses of rough joint surfaces under dynamic normal displacement conditions
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作者 ZHU Qiang YIN Qian +9 位作者 TAO Zhi-gang HE Man-chao ZHENG Bo-wen JING Hong-wen REN Shu-lin ZHANG Qiang MENG Bo BAI Dong-feng WU Sai-sai WU Jiang-yu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2393-2410,共18页
A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating... A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating geological disasters.This study conducted shear experiments on rough rock joints under displacement-controlled dynamic normal loads,investigating the shear behaviors of joints across varying initial normal loads,normal loading frequencies,and normal loading amplitudes.Experimental results showed that the peak/valley shear force values increased with initial normal loads and normal loading frequencies but showed an initial increase followed by a decrease with normal loading amplitudes.Dynamic normal loading can either increase or decrease shear strength,while this study demonstrates that higher frequencies lead to enhanced friction.Increased initial normal loading and normal loading frequency result in a gradual decrease in joint roughness coefficient(JRC)values of joint surfaces after shearing.Positive correlations existed between frictional energy dissipation and peak shear forces,while post-shear joint surface roughness exhibited a negative correlation with peak shear forces through linear regression analysis.This study contributes to a better understanding of the sliding responses and shear mechanical characteristics of rock joints under dynamic disturbances. 展开更多
关键词 dynamic normal displacement shear strength variations phase lag phenomenon STICK-SLIP
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Normalizing Treatment Effects on Carbide Morphology and Mechanical Properties of Low Alloy Wear Resistant Cast Iron 被引量:1
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作者 Deliang Meng Jianhua Liu Ruijun Zhang 《材料科学与工程(中英文版)》 2010年第2期52-55,共4页
关键词 低合金耐磨铸铁 碳化物形态 力学性能 正火处理 光学显微镜 白口铸铁 测试手段 扫描电镜
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A novel mitigation measure for normal fault-induced deformations on pile-raft systems
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作者 Mohammadreza Jahanshahi Nowkandeh Mehdi Ashtiani 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期15-33,共19页
Evidence from recent earthquakes has shown destructive consequences of fault-induced permanent ground movement on structures.Such observations have increased the demand for improvements in the design of structures tha... Evidence from recent earthquakes has shown destructive consequences of fault-induced permanent ground movement on structures.Such observations have increased the demand for improvements in the design of structures that are dramatically vulnerable to surface fault ruptures.In this study a novel connection between the raft and the piles is proposed to mitigate the hazards associated with a normal fault on pile-raft systems by means of 3D finite element(FE)modeling.Before embarking on the parametric study,the strain-softening constitutive law used for numerical modeling of the sand has been validated against centrifuge test results.The exact location of the fix-head and unconnected pile-raft systems relative to the outcropping fault rupture in the free-field is parametrically investigated,revealing different failure mechanisms.The performance of the proposed connection for protecting the pile-raft system against normal fault-induced deformations is assessed by comparing the geotechnical and structural responses of both types of foundation.The results indicate that the pocket connection can relatively reduce the cap rotation and horizontal and vertical displacements of the raft in most scenarios.The proposed connection decreases the bending moment response of the piles to their bending moment capacity,verging on a fault offset of 0.6 m at bedrock. 展开更多
关键词 normal fault rupture failure mechanism pile-raft system pocket connection finite element modeling
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