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Harnessing data using symbolic regression methods for discovering novel paradigms in physics

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 1-11页

作者： jianyang guo Wan-jian yin College of Energy Soochow Institute for Energy and Materials Innovations(SIEMIS)Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySuzhou 215006China Shanghai Qi Zhi Institute Shanghai 200232China Light Industry Institute of Electrochemical Power Sources Soochow UniversitySuzhou 215006China

In recent years,machine-learning methods have profoundly impacted research in the interdisciplinary fields of ***,most machine-learning models lack interpretability,and physicists doubt the credibility of their conclusions because they cannot be combined with prior physical ***,this review focuses on symbolic regression,which is an interpretable machine-learning ***,the relevant concepts of machine learning are introduced in conjunction with ***,we provide an overview of symbolic regression ***,the recent directions for the application of symbolic regression methods in different subfields of physics are outlined,and an overview of the ways in which the applications of symbolic regression have evolved in the realm of physics is *** major aim of this review is to introduce the basic principles of symbolic regression and explain its applications in the field of physics.

关键词： machine learning genetic programming symbolic regression

Attaining synergetic equilibrium of electrical conductivity and tensile strength in GQDs@GN/Cu composites through multi-scale intragranular and intergranular reinforcements

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Rare Metals 2024年第1期43卷 366-379页

作者： Shuang-yin Zhang Liang Liu Rui Bao jian-Hong Yi Sheng-Da guo Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and TechnologyKunming 650093China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

The configuration and quality of reinforcements, as well as the robustness of interfacial bonding,holding a critical significance in determining the concurrence between electrical conductivity and mechanical strength in metal matrix composites. In this study, citric acid was employed as the precursor for synthesizing multiscale carbon nanomaterials(graphene quantum dots and graphene, abbreviated as GQDs and GN). The GQDs@GN/Cu composites were fabricated through a segmented ball milling process in conjunction with subsequent spark plasma sintering(SPS). The intragranular GQDs and intergranular GQDs@GN had synergistically reinforced Cu composites through Orowan strengthening, load transfer strengthening and refinement strengthening. Furthermore,the robust interface bonding between GQDs@GN and Cu effectively mitigated interfacial impedance stemming from electron-boundary scattering. The yield strength and ultimate tensile strength of the GQDs@GN/Cu composites were recorded as 270 and 314 MPa, respectively, representing an improvement of 92 and 28% over pure Cu, while maintaining electrical conductivity at a level comparable to that of pure Cu. This study advances the understanding of the possibility of realizing a synergistic compatibility between electrical conductivity and mechanical strength in Cu composites.

关键词： Cu matrix composites Interface bonding Mechanical property Graphene quantum dots(GQDs) Electrical conductivity

Fine classification of rice paddy using multitemporal compact polarimetric SAR C band data based on machine learning methods

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Frontiers of Earth Science 2024年第1期18卷 30-43页

作者： Xianyu guo Junjun yin Kun LI jian YANG Huimin ZOU Fukun YANG School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875China

Rice is an important food crop for human *** distinguishing different varieties and sowing methods of rice on a large scale can provide more accurate information for rice growth monitoring,yield estimation,and phenological monitoring,which has significance for the development of modern *** polarimetric(CP)synthetic aperture radar(SAR)provides multichannel information and shows great potential for rice monitoring and ***,the use of machine learning methods to build classification models is a controversial *** this paper,the advantages of CP SAR data,the powerful learning ability of machine learning,and the important factors of the rice growth cycle were taken into account to achieve high-precision and fine classification of rice ***,CP SAR data were simulated by using the seven temporal RADARSAT-2 C-band data ***,20-two CP SAR parameters were extracted from each of the seven temporal CP SAR data *** addition,we fully considered the change degree of CP SAR parameters on a time scale(ΔCP_(DoY)).Six machine learning methods were employed to carry out the fine classification of rice *** results show that the classification methods of machine learning based on multitemporal CP SAR data can obtain better results in the fine classification of rice paddies by considering the parameters ofΔCP_(DoY).The overall accuracy is greater than 95.05%,and the Kappa coefficient is greater than *** them,the random forest(RF)and support vector machine(SVM)achieve the best results,with an overall accuracy reaching 97.32%and 97.37%,respectively,and Kappa coefficient values reaching 0.965 and 0.966,*** the two types of rice paddies,the average accuracy of the transplant hybrid(T-H)rice paddy is greater than 90.64%,and the highest accuracy is 95.95%.The average accuracy of direct-sown japonica(D-J)rice paddy is greater than 92.57%,and the highest accuracy is 96.13%.

关键词： compact polarimetric(CP)SAR rice paddy machine learning fine classification multitemporal

cKBET:assessing goodness of batch effect correction for single-cell RNA-seq

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Frontiers of Computer Science 2024年第1期18卷 215-228页

作者： Yameng ZHAO yin guo Limin LI School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China

Single-cell RNA sequencing reveals the gene structure and gene expression status of a single cell,which can reflect the heterogeneity between ***,batch effects caused by non-biological factors may hinder data integration and downstream *** the batch effect can be evaluated by visualizing the data,which actually is subjective and *** this work,we propose a quantitative method cKBET,which considers the batch and cell type information *** cKBET method accesses batch effects by comparing the global and local fraction of cells of different batches in different cell *** verify the performance of our cKBET method on simulated and real biological data *** experimental results show that our cKBET method is superior to existing methods in most *** general,our cKBET method can detect batch effect with either balanced or unbalanced cell types,and thus evaluate batch correction methods.

关键词： single-cell RNA-seq dataset b batch effect assessment cKBET method

Thermodynamic analysis of Na−S−Fe−H_(2)O system for Bayer process

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Transactions of Nonferrous Metals Society of China 2022年第6期32卷 2046-2060页

作者： Xue-jiao ZHOU Fei TAN Yong-li CHEN jian-guo yin Wen-tang XIA Qing-yun HUANG Xu-dong GAO School of Metallurgical and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China

Thermodynamic diagrams of Na−S−Fe−H_(2)O system were constructed to analyze the behavior of sulfur and iron in the Bayer *** digestion,iron mainly exists as Fe_(3)O_(4) and Fe_(2)O_(3) in red mud,and partial iron transfers into solution as Fe(OH)_(3)^(−),HFeO_(2)^(−),Fe(OH)_(4)^(−)and Fe(OH)_(4)^(2−).The dominant species of sulfur is S^(2−),followed by SO_(4)^(2−),and then SO_(3)^(2−)and S_(2)O_(3)^(2−).The thermodynamic analysis is consistent with the iron and sulfur species distribution in the solution obtained by *** the temperature decreases,sulfur and iron can combine and *** low potential and reducing temperature are beneficial to removing them from the *** patterns show that NaFeS_(2)·2H_(2)O,FeS and FeS_(2) widely appear in red mud and precipitates of pyrite and high-sulfur bauxite digestion *** analysis can be utilized to guide the simultaneous removal of sulfur and iron in the Bayer process.

关键词： high-sulfur bauxite Na−S−Fe−H_(2)O system thermodynamic analysis simultaneous removal sulfur iron Bayer process

A Compact UHF Antenna Based on Hilbert Fractal Elements and a Serpentine Arrangement for Detecting Partial Discharg

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Energy Engineering 2024年第5期121卷 1127-1141页

作者： Xiang Lin jian Fang Ming Zhang Kuang yin Yan Tian yingfei guo Qianggang Wang Guangzhou Power Supply Bureau of Guangdong Power Grid Co. Ltd.China Southern Power GridGuangzhou510620China State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqing400044China

Efforts to protect electric power systems from faults have commonly relied on the use of ultra-high frequency(UHF)antennas for detecting partial discharge(PD)as a common precursor to ***,the effectiveness of existing UHF antennas suffers from a number of challenges such as limited bandwidth,relatively large physical size,and low detection *** present study addresses these issues by proposing a compact microstrip patch antenna with fixed dimensions of 100 mm×100 mm×1.6 *** results of computations yield an optimized antenna design consisting of 2nd-order Hilbert fractal units positioned within a four-layer serpentine arrangement with a fractal unit connection distance of 3.0 ***,the optimized antenna design achieves a detection bandwidth for which the voltage standing wave ratio is less than 2 that is approximately 97.3%of the UHF frequency range(0.3–3 GHz).Finally,a prototype antenna is fabricated using standard printed circuit board technology,and the results of experiments demonstrate that the proposed antenna is capable of detecting PD signals at a distance of 8 m from the discharge source.

关键词： Power system fault partial discharge UHF antenna fractal antenna micro-strip antenna

Influence of Electroshocking Treatment on Microstructure and Mechanical Properties of Ti-6.5Al-3.5Mo-1.5Zr-0.3Si Thin-Wall Specimen Manufactured by Laser Melting Deposition

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 145-158页

作者： Yan Wen Xuan Sun jian Zhou Bingliang Liu Haojie guo Yuxin Li Fei yin Liqiang Wang Lechun Xie Lin Hua Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan430070China Hubei Longzhong Laboratory Xiangyang441000China Shanghai Aircraft Manufacturing Co. Ltd.Commercial Aircraft Corporation of ChinaLtd.Shanghai201324China State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China

In order to improve the properties of titanium alloys manufactured by laser melting deposition(LMD),the electroshocking treatment(EST)was proposed in this *** effects of EST on microstructure and mechanical properties of LMD Ti-6.5Al-3.5Mo-1.5Zr-0.3Si were *** results showed that the width of the heat affected band decreased and disappeared under the thermal and athermal effects of EST,resulting in the uniform *** the microstructure,theαlaths became coarser gradually,and the quantity ofα/βinterface was *** reduction of the quantity ofα/βinterface leads to make less resistant to dislocation,resulting in the reduction in hardness and *** discontinuous grain boundaryαphase and nucleationαcolony near grain boundary inhibited the crack propagation and improved the ***,EST can manipulate the microstructure and improve the mechanical properties of LMD titanium alloys.

关键词： Electroshocking treatment(EST) Laser melting deposition(LMD) Titanium alloy Microstructure Mechanical properties

A Dual-Task Learning Approach for Bearing Anomaly Detection and State Evaluation of Safe Region

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 229-241页

作者： Yuhua yin Zhiliang Liu Bin guo Mingjian Zuo School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Qingdao International Academician Park Research Institute Qingdao 266041China

Predictive maintenance has emerged as an effective tool for curbing maintenance costs,yet prevailing research predominantly concentrates on the abnormal *** the ostensibly stable healthy phase,the reliance on anomaly detection to preempt equipment malfunctions faces the challenge of sudden anomaly *** address this challenge,this paper proposes a dual-task learning approach for bearing anomaly detection and state evaluation of safe *** proposed method transforms the execution of the two tasks into an optimization issue of the hypersphere *** leveraging the monotonicity and distinguishability pertinent to the tasks as the foundation for optimization,it reconstructs the SVDD model to ensure equilibrium in the model’s performance across the two *** experiments verify the proposed method’s effectiveness,which is interpreted from the perspectives of parameter adjustment and enveloping *** the meantime,experimental results also show two deficiencies in anomaly detection accuracy and state evaluation *** theoretical analysis inspires us to focus on feature extraction and data collection to achieve *** proposed method lays the foundation for realizing predictive maintenance in a healthy stage by improving condition awareness in safe regions.

关键词： Bearing condition monitoring Anomaly detection Safe region Support vector data description

Heyingwuzi formulation alleviates diabetic retinopathy by promoting mitophagy via the HIF-1α/BNIP3/NIX axis

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World Journal of Diabetes 2024年第6期15卷 1317-1339页

作者： Jia-Jun Wu Shu-Yan Zhang Lin Mu Zhi-guo Dong yin-jian Zhang Department of Ophthalmology Longhua Hospital Shanghai University of Traditional Chinese MedicineShanghai 200032China Department of Ophthalmology Eye and ENT HospitalFudan UniversityShanghai 200031China

BACKGROUND Diabetic retinopathy(DR)is the primary cause of visual problems in patients with *** Heyingwuzi formulation(HYWZF)is effective against *** To determine the HYWZF prevention mechanisms,especially those underlying *** Human retinal capillary endothelial cells(HRCECs)were treated with high glucose(hg),HYWZF serum,PX-478,or Mdivi-1 in ***,cell counting kit-8,transwell,and tube formation assays were used to evaluate HRCEC proliferation,invasion,and tube formation,*** electron microscopy was used to assess mitochondrial morphology,and Western blotting was used to determine the protein *** cytometry was used to assess cell apoptosis,reactive oxygen species(ROS)production,and mitochondrial membrane ***,C57BL/6 mice were established in vivo using streptozotocin and treated with HYWZF for four *** glucose levels and body weight were monitored *** in retinal characteristics were evaluated using hematoxylin and eosin,tar violet,and periodic acid-Schiff *** levels in retinal tissues were determined via Western blotting,immunohistochemistry,and *** HYWZF inhibited excessive ROS production,apoptosis,tube formation,and invasion in hg-induced HRCECs via mitochondrial autophagy in *** increased the mRNA expression levels of BCL2-interacting protein 3(BNIP3),FUN14 domain-containing 1,BNIP3-like(BNIP3L,also known as NIX),PARKIN,PTEN-induced kinase 1,and hypoxia-inducible factor(HIF)-1α.Moreover,it downregulated the protein levels of vascular endothelial cell growth factor and increased the light chain 3-II/I ***,PX-478 and Mdivi-1 reversed these ***,PX-478 and Mdivi-1 rescued the effects of HYWZF by decreasing oxidative stress and apoptosis and increasing *** intervention improved the symptoms of diabetes,tissue damage,number of acellular capillaries,and oxidative stress in ***,in vivo

关键词： Diabetic retinopathy HIF-1α/BNIP3/NIX axis Mitophagy Heyingwuzi formulation Traditional Chinese medicine