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IFCEM based recognition method for target with interval-overlapped hybrid attributes

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Journal of Systems Engineering and Electronics 2023年第2期34卷 408-421页

作者： GUAN Xin LI Shuangming SUN Guidong WANG Haibin Naval Aviation University Yantai 264001China Unit 92941 of PLA Huludao 125001China Unit 32801 of PLA Beijing 100082China

When the attributes of unknown targets are not just numerical attributes,but hybrid attributes containing linguistic attributes,the existing recognition methods are not effective.In addition,it is more difficult to identify the unknown targets densely distributed in the feature space,especially when there is interval overlap between attribute measurements of different target classes.To address these problems,a novel method based on intuitionistic fuzzy comprehensive evaluation model(IFCEM)is proposed.For numerical attributes,targets in the database are divided into individual classes and overlapping classes,and for linguistic attributes,continuous interval-valued linguistic term set(CIVLTS)is used to describe target characteristic.A cloud modelbased method and an area-based method are proposed to obtain intuitionistic fuzzy decision information of query target on numerical attributes and linguistic attributes respectively.An improved inverse weighted kernel fuzzy c-means(IWK-FCM)algorithm is proposed for solution of attribute weight vector.The possibility matrix is applied to determine the identity and category of query target.Finally,a case study composed of parameter sensitivity analysis,recognition accuracy analysis.and comparison with other methods,is taken to verify the superiority of the proposed method.

关键词： intuitionistic fuzzy comprehensive evaluation model(IFCEM) interval overlapping cloud model area-based method inverse weighted kernel fuzzy c-means(IWK-FCM)

liquid concentration distribution and planar interface instability at an abruptly changing pulling velocity in directional solidification

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Science China(Technological Sciences) 2007年第1期50卷 118-126页

作者： LI Shuangming FU HengZhi State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

liquid concentration distribution is seriously affected by an abruptly changing pulling velocity under directional solidification. Theoretical and numerical investi-gations indicate that at the pulling velocity jumping from V0 to V, the solidification system does not achieve the pulling velocity V immediately, and it goes through a non-steady-state transition zone. As the pulling velocity abruptly increases (V/V0 > 1), interface liquid concentration firstly increases to the maximum and then de-creases to the steady-state value. The magnitude of interface liquid concentration at the beginning increases with V/V0, the initial pulling velocity V0 and the tem-perature gradient GL in the liquid. At the same time, solute diffusion length reduces with V/V0 and GL. In contrast, the minimum of interface liquid concentration falls with V/V0 at the pulling velocity decreasing abruptly. As the interface liquid con-centration enriched at V/V0 > 1 is more than the value required for the planar inter-face to keep stable, the solid/liquid interface may become unstable. The analytical results are in agreement with the numerical calculation results of Al-2%Cu alloy.

关键词： directional solidification abruptly changing velocity concentration distribution Al-Cu alloy

Seaweed pattern formation in the non-axially directional solidification of 2D-like and 3D Al-3 wt.% Mg single crystal

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Journal of Materials Science & Technology 2023年第16期147卷 1-5页

作者： Yumin Wang Bin Yang shuangming li Xin Cao Zhongli liu Hui Xing College of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005China Inner Mongolia Metal Material Research Institute Yantai 264003China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Shaanxi Key Laboratory of Condensed Matter Structure and PropertiesNorthwestern Polytechnical UniversityXi’an 710129China

1.Introduction Microstructures are at the centre of materials science and engineering and play an essential role in determining the in-service mechanical properties of metallic alloys[1–4].Extensive theoretical and experimental investigations have been undertaken to describe and determine solidification microstructures as a function of solidification conditions.The seaweed pattern is one of the most important classes of microstructural patterns[5–7].The characteristic of this pattern is that its extending tips—unlike the behaviour observed in needle-like dendrites—split repeatedly into two or more parts.

关键词： solidification pattern directional

Application of X-ray absorption spectroscopy in carbon-supported electrocatalysts

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Nano Research 2023年第11期16卷 12438-12452页

作者： Beibei Sheng Yongheng Chu Dengfeng Cao Yujian Xia Chongjing liu shuangming Chen li Song National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230026China

Breakthroughs in energy storage and conversion devices depend heavily on the exploration of low-cost and high-performance materials.Carbon-supported electrocatalysts with dimensional varieties have recently attracted significant attention due to their strong structural flexibility and easy accessibility.Nevertheless,understanding the connection between their electronic,structural properties,and catalytic performance must remain a top priority.Synchrotron radiation(SR)X-ray absorption spectroscopy(XAS)techniques,including hard XAS and soft XAS,are recognized as efficient and comprehensive platforms for probing the surface,interface,and bulk electronic structure of elements of interest in the materials community.In the past decade,the flourishing development of materials science and advanced characterization technologies have led to a deeper understanding at different temporal,longitudinal,and spatial scales.In this review,we briefly describe the concept of XAS techniques and summarize their recent progress in addressing scientific questions on carbon-supported electrocatalysts through the development of advanced instruments and experimental methods.We then discuss the remaining challenges and potential research directions in nextgeneration materials frontiers,and suggest challenges and perspectives for shedding light on the structure–activity relationship.

关键词： synchrotron radiation hard X-ray absorption spectroscopy(XAS) soft XAS carbon-supported electrocatalysts

Effect of abruptly changing withdrawal rate on solidification microstructure in directionally solidified Al-4.5wt%Cu alloy

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China Foundry 2014年第1期11卷 8-13页

作者： Yang Luyan LI Shuangming Zhong Hong Ren Ruohua Fu Hengzhi State Key Laboratory of Solidif ication Processing Northwestern Polytechnical University

Al-4.5wt.%Cu alloy has been directionally solidified at constant and abruptly changing withdrawal rates, respectively. The effects of the withdrawal rate on solidification microstructure, primary dendrite arm spacing(PDAS) and liquid solute distribution in front of the solid-liquid interface were investigated. The experimental results for the PDAS at a constant withdrawal rate agree well with the values calculated by the Hunt, Trivedi and Hunt-Lu models. At an abrupt change in the withdrawal rate, the maximum to minimum ratio of the PDAS at a given solidification parameter, i.e. λ1max/λ1min, is more than 2, and the PDAS values are remarkably history-dependent. Further, the liquid-solute distribution curve based on theoretical calculation shows that the larger the initial withdrawal rate is, the smaller the minimum of liquid solute concentration in front of the solid-liquid interface is after the abrupt change in withdrawal rate.

关键词： directional solidifi cation abrupt change of withdrawal rate primary dendrite arm spacing liquid-solute distribution Al-4.5wt.%Cu alloy

Effect of sample diameter on primary and secondary dendrite arm spacings during directional solidification of Pb-26wt.%Bi hypo-peritectic alloy

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Rare Metals 2011年第4期30卷 424-431页

作者： HU Xiaowu YAN Hong CHEN Wenjing LI Shuangming FU Hengzhi School of Mechanical-Electrical Engineering Nanchang University Nanchang 330031 China Department of Applied Physics Northwestern P olytechnical University Xi＇an 710072 China State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China

The microstructure scales of dendrites, such as primary and secondary dendrite arm spacings, control the segregation profiles and the formation of secondary phases within interdendritic regions, which determine the properties of solidified structures. Investigations on primary and secondary dendrite arm spacings of primary a-phase during directionally solidified Pb-26wt%Bi hypo-peritectic alloy were carried out in this research, and systematic studies were conducted using cylindrical samples with different diameters （Ф = 1.8 and 7.0 mm） in order to analyze the effects of sample diameter on the primary and secondary dendrite arm spacings. In this work, the dependence of dendrite arm spacings on growth velocity was established. In addition, the experimental data concerning the primary and secondary dendrite ann spacings were compared with the main predictive dendritic models from the literatures. A comparison between experimental results for dendrite arm spacings of the 1.8-mm-diameter sample and 7.0-ram-diameter sample was also conducted.

关键词： lead bismuth alloys dendrite arm spacing directional solidification dendrites

A GMDA clustering algorithm based on evidential reasoning architecture

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Chinese Journal of Aeronautics 2024年第1期37卷 300-311页

作者： Haibin WANG Xin GUAN Xiao YI shuangming li Guidong SUN Naval Aviation University Yantai 264001China Unit 92941 of PLA Huludao 125001China Institute of Systems Engineering Beijing 100082China

The traditional clustering algorithm is difficult to deal with the identification and division of uncertain objects distributed in the overlapping region,and aimed at solving this problem,the Evidential Clustering based on General Mixture Decomposition Algorithm(GMDA-EC)is proposed.First,the belief classification of target cluster is carried out,and the sample category of target distribution overlapping region is extended.Then,on the basis of General Mixture Decomposition Algorithm(GMDA)clustering,the fusion model of evidence credibility and evidence relative entropy is constructed to generate the basic probability assignment of the target and achieve the belief division of the target.Finally,the performance of the algorithm is verified by the synthetic dataset and the measured dataset.The experimental results show that the algorithm can reflect the uncertainty of target clustering results more comprehensively than the traditional probabilistic partition clustering algorithm.

关键词： Evidential clustering Credal partition Evidential reasoning Mixed decomposition Gaussian mixture model

Amorphous nickel-iron oxides/carbon nanohybrids for an efficient and durable oxygen evolution reaction

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Nano Research 2017年第11期10卷 3629-3637页

作者： Bo li shuangming Chen Jie Tian Ming Gong Hangxun Xu li Song CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 China National Synchrotron Radiation Laboratory CAS Center for Excellence in Nanoscience University of Science and Technology of ChinaHefei 230029 China Engineering and Materials Science Experiment Center University of Science and Technology of China Hefei 230027 China

Highly efficient and durable water oxidation electrocatalysts are critically important in a wide range of clean energy technologies,including water electrolyzers and rechargeable metal-air batteries.Here,we report a novel sonochemical approach to synthesize amorphous nickel-iron oxides/carbon nanohybrids with tunable compositions for the oxygen evolution reaction （OER）.The sonochemically synthesized amorphous electrocatalysts with optimal composition exhibit a low overpotential of 290 mV at 10 mA＆#183;cm-2 and a Tafel slope of 31 mV＆#183;decade-1 in a 0.1 M KOH electrolyte,outperforming the benchmark RuO2 catalyst.Meanwhile,these nanohybrids are also highly stable and remain amorphous even after prolonged cycling.In addition to amorphism,sonochemistry endows as-prepared nickel-iron oxides/carbon nanohybrids with a simultaneously formed carbon scaffold and internal Ni（0）,which can enhance the stability and activity for the OER.This work demonstrates that sonochemistry is a unique method for synthesizing amorphous metal oxides toward an efficient and durable OER.

关键词： amorphous meal oxides electrocatalysis,oxygen evolution reaction,sonochemistry,X-ray absorption near edge structure

Peritectic phase growth in directionally solidified Cu-70% Sn alloy

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Science China(Physics,Mechanics & Astronomy) 2007年第4期50卷 451-459页

作者： LüHaiYan LI Shuangming liU lin FU HengZhi State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The growth mechanism of the peritectic η phase involving the peritectic reaction and peritectic transformation in Cu-70%Sn alloy was investigated under directional solidification.The results show that a major growth mechanism in thickening of the peritectic η-layer is not the peritectic reaction but the peritectic transformation.The transformation temperature and isothermal time play crucial roles in determining the volume fraction and the thickness of the peritectic η phase.With the increase of the temperature and isothermal time,the volume fraction of the peritectic η phase increases.The regressed data show that the relationship between the thickness of η phase(x)and the transformation temperature(T)meets the following equation ln x=6.51673 1T.Additionally,there exists a relationship between the thickness of the η phase(x)and the isothermal time(t)at the 9 mm solidification distance be-low the peritectic reaction interface,x =0.72t1/2,which is consistent with the theo-retical model.

关键词： Cu-70%Sn peritectic alloy peritectic reaction peritectic transformation directional solidification