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Application of rough graph in relationship mining

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Journal of Systems Engineering and Electronics 2008年第4期19卷 742-747页

作者： He tong xue Peijun Shi Kaiquan School of Mathematics and System Sciences Shandong Univ. Jinan 250100 P. R. China

Based on the definition of class shortest path in weighted rough graph, class shortest path algorithm in weighted rough graph is presented, which extends classical shortest path algorithm. The application in relations... 详细信息

关键词： rough graph weighted rough graph class shortest path dijkstra algorithm relationship mining

Interdecadal Variability of Summer Precipitation in Northwest China and Associated Atmospheric Circulation Changes

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Journal of Meteorological Research 2022年第6期36卷 824-840页

作者： tong xue Yihui DING Chunhui LU Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081 University of Chinese Academy of Sciences Beijing 100049 CMA Climate Studies Key Laboratory China Meteorological Administration(CMA)Beijing 100081 National Climate Centre China Meteorological AdministrationBeijing 100081 CMATraining Centre China Meteorological AdministrationBeijing 100081

Daily precipitation data from 149 rain gauge stations in China and NCEP-NCAR reanalysis data during 1961-2018are used to investigate the interdecadal variability of summer precipitation in Northwest China and related *** results suggest that,on the interdecadal timescale,Northwest China shifts into a rainy period from the year 1987,with an increase in the precipitation amount and intensity;an increase in the probability of moderate rain,heavy rain,torrential rain,and extremely heavy rain;and a decrease in the probability of light *** than 60%of the increase in precipitation can be attributed to rainfall with intensity above the grade of heavy *** associated interdecadal variability of atmospheric circulations over midlatitude Eurasia in summer is examined and it is found that the interdecadal variability is mainly characterized by the Silk Road pattern(SRP),with a cyclonic circulation anomaly and an anticyclonic circulation anomaly over central Asia and Mongolia,respectively;enhanced ascending motion and atmospheric instability in Northwest China;and strengthened easterly winds caused by the Mongolian anticyclonic anomaly along the northern boundary of the Tibetan *** the south side of the Mongolian anticyclone,the water vapor transported from the Pacific and Indian Oceans as well as the South China Sea to Northwest China by easterly winds increases significantly,providing the main water vapor source for the increase in precipitation in Northwest China on the interdecadal *** transition of the Atlantic multidecadal oscillation to a positive phase may be the main cause of the interdecadal transition of the SRP to a positive phase,resulting in the interdecadal increase in summer precipitation in Northwest China.

关键词： Northwest China precipitation interdecadal variability Silk Road pattern Atlantic multidecadal oscillation

Analysis of Metal Forming in Two-Roll Cross Wedge Rolling Process Using Finite Element Method

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Journal of Iron and Steel Research International 2009年第1期16卷 38-43页

作者： WANG Min-ting LI xue-tong DU Feng-shan College of Mechanical and Engineering Yanshan University Qinhuangdao 066004 Hebei China

A simulation model for two-roll cross wedge rolling （CWR） was presented by using three-dimensional rigid-plastic finite element method （FEM）. The whole forming process of CWR, including knifing zone, guiding zone, stretching zone, and sizing zone, was simulated using the model in which dynamic adaptive remeshing technology for tetrahedral solid elements was used to fix element distortion. Based on the simulation results, the distributions of metal flow field, strain field, and damage field, and the geometry of the workpiece＇s end were analyzed. These results could provide theoretical guidance for realizing net shaping and reasonable design of tools.

关键词： cross wedge rolling finite element method plastic forming simulation

Coupling Thermomechanical and Microstructural FE Analysis in Plate Rolling Process

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Journal of Iron and Steel Research International 2008年第4期15卷 42-50页

作者： LI xue-tong WANG Min-ting DU Feng-shan College of Mechanical Engineering Yanshan University Qinhuangdao 066004 Hebei China

Using three-dimensional rigid-viscoplastic finite element method （FEM）, a coupling multivariable numerical simulation model for steel plate rolling has been established based on the physical metallurgy microstructural evolution rule and experiential equations. The effects of reduction, deformation temperature, and rolling speed on the deformation parameters and microstructure in plate rolling were investigated using the model. After a typical rolling process of steel plate 16Mn is simulated, the strain, temperature, and microstructure distributions are presented, as well as the ferrite grain transformation during the period of cooling. By comparing the calculated ferrite grain sizes with measured ones, the model is validated.

关键词： hot rolling plate FEM microstructure coupling

Alteration of functional connectivity in patients with Alzheimer’s disease revealed by resting-state functional magnetic resonance imaging

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Neural Regeneration Research 2020年第2期15卷 285-292页

作者： Jie Zhao Yu-Hang Du xue-tong Ding xue-Hu Wang Guo-Zun Men School of Electronic and Information Engineering Hebei UniversityBaodingHebei ProvinceChina Research Center of Machine Vision Engineering & Technology of Hebei Province BaodingHebei ProvinceChina Key Laboratory of Digital Medical Engineering of Hebei Province BaodingHebei ProvinceChina School of Economics Hebei UniversityBaodingHebei ProvinceChina

The main symptom of patients with Alzheimer’s disease is cognitive dysfunction. Alzheimer’s disease is mainly diagnosed based on changes in brain structure. Functional connectivity reflects the synchrony of functional activities between non-adjacent brain regions, and changes in functional connectivity appear earlier than those in brain structure. In this study, we detected resting-state functional connectivity changes in patients with Alzheimer’s disease to provide reference evidence for disease prediction. Functional magnetic resonance imaging data from patients with Alzheimer’s disease were used to show whether particular white and gray matter areas had certain functional connectivity patterns and if these patterns changed with disease severity. In nine white and corresponding gray matter regions, correlations of normal cognition, early mild cognitive impairment, and late mild cognitive impairment with blood oxygen level-dependent signal time series were detected. Average correlation coefficient analysis indicated functional connectivity patterns between white and gray matter in the resting state of patients with Alzheimer’s disease. Functional connectivity pattern variation correlated with disease severity, with some regions having relatively strong or weak correlations. We found that the correlation coefficients of five regions were 0.3–0.5 in patients with normal cognition and 0–0.2 in those developing Alzheimer’s disease. Moreover, in the other four regions, the range increased to 0.45–0.7 with increasing cognitive impairment. In some white and gray matter areas, there were specific connectivity patterns. Changes in regional white and gray matter connectivity patterns may be used to predict Alzheimer’s disease;however, detailed information on specific connectivity patterns is needed. All study data were obtained from the Alzheimer’s Disease Neuroimaging Initiative Library of the Image and Data Archive Database.

关键词： Alzheimer's disease blood oxygen level-dependent signal correlation coefficient functional connectivity pattern functional magnetic resonance imaging gray matter resting state white matter

Head and Tail Shape Control in Vertical-Horizontal Rolling Process by FEM

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Journal of Iron and Steel Research International 2009年第5期16卷 35-42页

作者： ZANG Xin-liang LI xue-tong DU Feng-shan Department of Mechanical Engineering Yanshan University Qinhuangdao 066004 Hebei China

Using 3D rigid-plastic finite element method （FEM）, a numerical simulation model for nonsteady state vertical-horizontal rolling process in roughing trains was built and was validated by comparing the simulated values with experimental ones of width and shape of the stock ends. According to certain 2050 roughing processing technologies, the short shape control （SSC） of the stock ends was investigated using the model. Based on the simulated results, a new SSC model was developed. The analyzed results showed that the new SSC model is effective in improving the shape of the stock ends.

关键词： hot rolling FEM simulation edging shape control

Composition and structure of coatings on Ti-6Al-4V alloy by micro-plasma oxidation in NaAlO2 solution

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 162-165页

作者： YAO Zhong-ping JIANG Zhao-hua SUN xue-tong WU Zheng-dong ZHANG xue-lin Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China

Compound ceramic coatings on Ti-6Al-4V alloy were prepared for different time by pulsed bi-polar micro-plasma oxidation (MPO) in NaAlO2 solution. The phase composition was studied by XRD. And the electrochemical impedance spectra (EIS) of the coatings were measured to study the structure of the coatings, combined with the surface morphology. Using the proper EIS interpreting software, the "equivalent circuit" of the coatings was established, and meanwhile fitting values of equivalent element were obtained. The results show that the coating is composed of Al2 TiO5, α-Al2O3 and rutile TiO2, of which Al2 TiO5 is the main crystalline. Increasing the MPO time, the contents of Al2TiO5, rutile TiO2 and α-Al2O3 in the surface of the coating increase. And the EIS analysis and the surface morphology of the coatings illustrates the double-layer structure of the coatings, and the outer layer is loosen and the inner layer is compact. With the increase of the oxidizing time, the surface coarse degree of the coatings and the porosity of the outer layer of the coating are increased while the compactness of the inner layer of the coating is improved.

关键词： micro-plasma oxidation ceramic coatings electrochemical impedance spectra Ti-6Al-4V alloy

Nanostructure Architectures of Tungsten Carbide for Methanol Electrooxidation Catalyst

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Chinese Journal of Chemistry 2016年第6期34卷 624-630页

作者： Yekun Jiang Meiqin Shi xue tong Youqun Chu Chunan Ma State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology College of Chemical Engineering Zhejiang University of Technology Hangzhou Zhejiang 310032 China

We reported a novel protocol to efficiently synthesize tungsten carbide （WC） nanomaterials with pure crystal structure and certain specific morphology. The key step in this protocol is the preparation of the catalyst precursor W18049 with surface oxygen vacancies. The existence of large quantities of oxygen vacancies gives plenty channels for diffusion and keeps the specific morphology of WC in the carbonization process. Efforts to build WC blocks with well-defined geometrical shapes （e.g., rods, wires, spheres and flakes） have further expanded its possibility to be the support for methanol electrooxidation catalyst. The platinum supported on pure phase WC materials served as an effective CO tolerant electrocatalyst for methanol oxidation. Electrochemical experiments indicated that the improved catalytic activity was related to the special morphologies of WC supports. Its sea urchin like feature leads to substantial interfaces between WC and Pt by preparing more anchor points for Pt loading and also the barriers for the subsequent crystal growth, which enhances the synergistic effect between WC and Pt.

关键词： carbides oxygen vacancy 3-dimensional block electrochemistry

Exploring the Interplay between Local Chain Structure and Stress Distribution in Polymer Networks

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Chinese Journal of Polymer Science 2024年第6期42卷 874-885页

作者： Jin-tong xue Yang Bai Li Peng Xian-Bo Huang Zhao-Yan Sun School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China National-certified Enterprise Technology Center Kingfa Science and Technology Co.Ltd.Guangzhou510663China

The mechanical behavior of polymer networks is intrinsically correlated with the local chain topology and chain *** this study,we delve into this relationship through the lens of coarse-grained molecular dynamics(CG-MD)*** aim is to illuminate the intricate interplay between local topology and stress distribution within polymer monomers,cross-linkers,and various components with distinct cross-link connections,thereby elucidating their collective impact on the mechanical properties of polymer *** mainly focus on how specific local structures contribute to the overall mechanical response of the *** particular,we employ local stress analysis to unravel the mechanics of these *** findings reveal the diverse responses of individual components,such as junctions,strands,cross-linkers between junctions,and dangling chain ends,when subjected to ***,we observe that these components exhibit varying degrees of deformation tolerance,underscoring the significance of their roles in determining the mechanical characteristics of the *** investigations highlight junctions as primary contributors to stress accumulation,and particles with higher local stress showing a stronger correlation between stress and Voronoi ***,our results indicate that both strands and cross-linkers between junctions exhibit heightened stress levels as strand lengths *** study enhances our understanding of the multifaceted factors governing the mechanical attributes of cross-linked polymer systems at the microstructural level.

关键词： Local chain structure Local stress Molecular dynamics simulation