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Augmented Industrial Data-Driven Modeling Under the Curse of Dimensionality

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IEEE/CAA Journal of Automatica Sinica 2023年第6期10卷 1445-1461页

作者： xiaoyu jiang Xiangyin Kong Zhiqiang Ge the State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China the Peng Cheng Laboratory Shenzhen 518000China

The curse of dimensionality refers to the problem o increased sparsity and computational complexity when dealing with high-dimensional *** recent years,the types and vari ables of industrial data have increased significantly,making data driven models more challenging to *** address this prob lem,data augmentation technology has been introduced as an effective tool to solve the sparsity problem of high-dimensiona industrial *** paper systematically explores and discusses the necessity,feasibility,and effectiveness of augmented indus trial data-driven modeling in the context of the curse of dimen sionality and virtual big ***,the process of data augmen tation modeling is analyzed,and the concept of data boosting augmentation is *** data boosting augmentation involves designing the reliability weight and actual-virtual weigh functions,and developing a double weighted partial least squares model to optimize the three stages of data generation,data fusion and *** approach significantly improves the inter pretability,effectiveness,and practicality of data augmentation in the industrial ***,the proposed method is verified using practical examples of fault diagnosis systems and virtua measurement systems in the *** results demonstrate the effectiveness of the proposed approach in improving the accu racy and robustness of data-driven models,making them more suitable for real-world industrial applications.

关键词： Index Terms—Curse of dimensionality data augmentation data-driven modeling industrial processes machine learning

Influence of Dislocation Pile-Up on Main Crack Propagation in Nanocrystals in the Hydrogen Environment

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Acta Mechanica Solida Sinica 2023年第6期36卷 851-859页

作者： Jiding Zhang Yue Sheng Hongda Yang Jinbo Wu xiaoyu jiang Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China

The influence of material micro-defects on the main crack growth under pure shear loading is studied *** mechanism behind the initiation of micro-cracks and crack propagation induced by dislocation accumulation near the grain boundary(GB)ismainly considered,and the influence of dislocation accumulation on the main crack propagation is *** research results reveal that the initiation of micro-cracks near the GB is prior to the propagation of the main *** a hydrogen environment,hydrogen can cause serious embrittlement of the crack tip and promote crack *** energy release rate in the main crack growth direction in the dislocation emission direction is the ***,the main crack will eventually merge with the micro-cracks at the GB along the direction of the slip band,resulting in fracture of the crystal *** research presented in this paper provides some new information for the first stage of crack propagation and contributes to the analysis of the mechanism of crystal metal fracture.

关键词： Crack propagation Dislocation emission Dislocation pile-up Grain boundary Energy release rate

MONTE CARLO SIMULATION OF POLARIZED LIGHT SCATTERING IN TISSUES

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Journal of Innovative Optical Health Sciences 2009年第2期2卷 131-135页

作者： TIANLIANG YUN WEI LI xiaoyu jiang HUI MA Laboratory of Optical Imaging and Sensing Graduate School at Shenzhen Tsinghua University Shenzhen 518055China Key Laboratory for Molecular and Nanosciences of Education Ministry Department of Physics Tsinghua University Beijing 100084China

We investigate the propagation of polarized light in fibrous tissues such as muscle and *** myofibrils and collagen fibers are approximated as long cylinders and the tissue phantom is composed of spherical and cylindrical *** apply Monte Carlo method based on this phantom to simulate and analyze polarization imaging process of *** good agreement between the simulation results and the experimental results validate the assumption of the phantom *** paper also presents how to describe the fiber orientation distribution and tissue anisotropy according to three parameters derived from the polarization imaging.

关键词： Monte Carlo polarized light anisotropy cylindrical scatterer

A green route to synthesize low-cost and high-performance hard carbon as promising sodium-ion battery anodes from sorghum stalk waste

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Green Energy & Environment 2017年第3期2卷 310-315页

作者： Xiaoming Zhu xiaoyu jiang Xiaoling Liu Lifen Xiao Yuliang Cao Hubei Collaboration Innovation Center of Non-power Nuclear Technology School of Nuclear Technology & Chemistry and Biology Hubei University of Science and Technology Hubei Key Lab.of Electrochemical Power Sources College of Chemistry and Molecular Sciences Wuhan University College of Chemistry Central China Normal University

Sodium-ion batteries(SIBs) have been considered to be potential candidates for next-generation low-cost energy storage systems due to the low-cost and abundance of Na resources. However, it is a big challenge to find suitable anode materials with low-cost and good performance for the application of SIBs. Hard carbon could be a promising anode material due to high capacity and expectable low-cost if originating from biomass. Herein, we report a hard carbon material derived from abundant and abandoned biomass of sorghum stalk through a simple carbonization method. The effects of carbonization temperature on microstructure and electrochemical performance are investigated. The hard carbon carbonized at 1300 ℃ delivers the best rate capability(172 mAh g^(-1) at 200 mA g^(-1)) and good cycling performance(245 mAh g^(-1) after 50 cycles at 20 mA g^(-1),96% capacity retention). This contribution provides a green route for transforming sorghum stalk waste into "treasure"of promising low-cost anode material for SIBs.

关键词： Sorghum stalk Hard carbon Anode Sodium-ion battery Carbonization

Stock index adjustments, analyst coverage and institutional holdings: Evidence from China

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China Journal of Accounting Research 2017年第3期10卷 281-293页

作者： Song Zhu xiaoyu jiang Xiaoli Ke xiaoyu Bai Business School Beijing Normal University Bank of China

Using 231 pairs of matched firms from 2009 to 2012 in Chinese stock market,we find that the stock index adjustment significantly affects the analyst coverage, which in addition to the stock index leads to more analyst coverage, while deletion from the stock index has no significant effect, indicating that stock index adjustment can significantly change the information environments of firms that are added to the index. An index adjustment also affects institutional holdings in consideration of new information(e.g., changes in fundamentals and information environments). Changes in institutional holdings are partially due to changes in analyst coverage, and both index funds and other types can change their portfolios in response to changes in the target firms' informativeness.

关键词： Stock index adjustment Analyst coverage Institutional holding

Video-based Person Re-identification Based on Distributed Cloud Computing

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Journal of Artificial Intelligence and Technology 2021年第2期1卷 110-120页

作者： Chengyan Zhong xiaoyu jiang Guanqiu Qi College of Automation Chongqing University of Posts and TelecommunicationsChongqing 400065China College of Intelligence Science and Technology Chongqing University of Posts and TelecommunicationsChongqing 400065China Computer Information Systems Department State University of New York at Buffalo StateBuffaloNY 14222USA

Person re-identification has been a hot research issues in the field of computer *** recent years,with the maturity of the theory,a large number of excellent methods have been ***,large-scale data sets and huge networks make training a time-consuming *** the same time,the parameters and their values generated during the training process also take up a lot of computer ***,we apply distributed cloud computing method to perform person re-identification *** distributed data storage method,pedestrian data sets and parameters are stored in cloud *** speed up operational efficiency and increase fault tolerance,we add data redundancy mechanism to copy and store data blocks to different nodes,and we propose a hash loop optimization algorithm to optimize the data distribution ***,we assign different layers of the re-identification network to different nodes to complete the training in the way of model *** comparing and analyzing the accuracy and operation speed of the distributed model on the video-based dataset MARS,the results show that our distributed model has a faster training speed.

关键词： person re-identification distributed cloud computing data redundancy mechanism

Rail fatigue crack propagation in high-speed wheel/rail rolling contact

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Journal of Modern Transportation 2017年第3期25卷 178-184页

作者： xiaoyu jiang Xiaotao Li Xu Li Shihao Cao School of Mechanics and Engineering Southwest Jiaotong University School of Civil Engineering Southwest Jiaotong University

To study the wheel/rail rolling contact fatigue of high-speed trains, we obtain the distribution of contact forces between wheel and rail by introducing the strain-rate effect. Based on the finite element simulation, a two-dimensional finite element model is established, and the process of a wheel rolling over a crack is analyzed to predict the crack propagation direction. The statistics of possible crack prop- agation angles are calculated by the maximum circumfer- ential stress criterion. The crack path is then obtained by using the average crack propagation angle as the crack propagation direction according to Weibull distribution. Results show that the rail crack mode of low-speed trains is different from that of high-speed trains. The rail crack propagation experiences a migration from opening mode to sliding mode under the low-speed trains; however, the rail crack mainly propagates in the opening mode under high- speed trains. Furthermore, the crack propagation rate for high-speed trains is faster than that for low-speed trains. The simulated crack paths are consistent with the experimental ones, which proves that it is reasonable to use the average value of possible crack propagation directions as the actual crack propagation direction.

关键词： Rolling contact fatigue Finite element Crackpropagation Weibull distribution

Strength of Intramolecular Hydrogen Bonds

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物理化学学报 2018年第3期34卷 278-285页

作者： jiang xiaoyu WU Wei MO Yirong College of Ecological Environment and Urban Construction Fujian University of Technology The State Key Laboratory of Physical Chemistry of Solid Surfaces iChEM Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry and College of Chemistry and Chemical Engineering Xiamen University Department of Chemistry Western Michigan University

The concept of resonance-assisted hydrogen bonds(RAHBs)highlights the synergistic interplay between theπ-resonance and hydrogen bonding *** concept has been well-accepted in academia and is widely used in ***,it has been argued that the seemingly enhanced intramolecular hydrogen bonding(IMHB)in unsaturated compounds may simply be a result of the constraints imposed by theσ-skeleton ***,it is crucial to estimate the strength of *** this work,we used two approaches to probe the resonance effect and estimate the strength of the IMHBs in the two exemplary cases of the enol forms of acetylacetone and *** approach is the block-localized wavefunction(BLW)method,which is a variant of the ab initio valence bond(VB)*** this approach,it is possible to derive the geometries and energetics with resonance shut *** other approach is Edmiston’s truncated localized molecular orbital(TLMO)technique,which monitors the energy changes by removing the delocalization tails from localized molecular *** integrated BLW and TLMO studies confirmed that the hydrogen bonding in these two molecules is indeed enhanced byπ-resonance,and that this enhancement is not a result ofσconstraints.

关键词： Resonance-assisted hydrogen bond Bond strength Valence bond Block-localized wavefunction Truncated localized molecular orbital

Plant property regulates soil bacterial community structure under altered precipitation regimes in a semi-arid desert grassland, China

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Journal of Arid Land 2023年第5期15卷 602-619页

作者： ZHANG Lihua GAO Han WANG Junfeng ZHAO Ruifeng WANG Mengmeng HAO Lianyi GUO Yafei jiang xiaoyu ZHONG Lingfei College of Geography and Environment Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Lanzhou 730070China College of Grassland Agriculture Northwest Agriculture and Forestry UniversityYangling 712100China

Variations of precipitation have great impacts on soil carbon cycle and decomposition of soil organic *** bacteria are crucial participants in regulating these ecological processes and vulnerable to altered *** the impacts of altered precipitation on soil bacterial community structure can provide a novel insight into the potential impacts of altered precipitation on soil carbon cycle and carbon storage of ***,soil bacterial community structure under a precipitation manipulation experiment was researched in a semi-arid desert grassland in Chinese Loess *** precipitation levels,i.e.,control,reduced and increased precipitation by 40%and 20%,respectively(referred here as CK,DP40,DP20,IP40,and IP20)were *** results showed that soil bacterial alpha diversity and rare bacteria significantly changed with altered precipitation,but the dominant bacteria and soil bacterial beta diversity did not change,which may be ascribed to the ecological strategy of soil *** linear discriminate analysis(LDA)effect size(LEfSe)method found that major response patterns of soil bacteria to altered precipitation were resource-limited and drought-tolerant *** addition,increasing precipitation greatly promoted inter-species competition,while decreasing precipitation highly facilitated inter-species *** changes in species interaction can promote different distribution ratios of bacterial populations under different precipitation *** structural equation model(SEM)analysis,with changes in precipitation,plant growth characteristics were found to be drivers of soil bacterial community composition,while soil properties were *** conclusion,our results indicated that in desert grassland ecosystem,the sensitive of soil rare bacteria to altered precipitation was stronger than that of dominant taxa,which may be related to the ecological strategy of bacteria,species interaction,and precipitation-induced var

关键词： plant-microbe interactions bacterial community diversity bacterial community composition bacterial interactions precipitation gradients