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Incomplete multi-view clustering via local and global co-regularization

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Science China(Information Sciences) 2022年第5期65卷 96-111页

作者： Jiye liang Xiaolin LIU liang bai Fuyuan CAO Dianhui WANG Key Laboratory of Computational Intelligence and Chinese Information Processing of Ministry of Education School of Computer and Information Technology Shanxi University Artificial Intelligence Research Institute China University of Mining and Technology Department of Computer Science and Computer Engineering La Trobe University

The incompleteness of multi-view data is a phenomenon associated with real-world data mining applications, which brings a huge challenge for multi-view clustering. Although various types of clustering methods, which try to obtain a complete and consensus clustering result from a latent subspace, have been developed to overcome this problem, most methods excessively rely on views-public instances to bridge the connection with view-private instances. When lacking sufficient views-public instances, existing methods fail to transmit the information among incomplete views effectively. To overcome this limitation, we propose an incomplete multi-view clustering algorithm via local and global co-regularization(IMVC-LG). In this algorithm, we define a new objective function that is composed of two terms: local clustering from each view and global clustering from multiple views, which constrain each other to exploit the local clustering information from different incomplete views and determine a global consensus clustering result, ***, an iterative optimization method is proposed to minimize the objective function. Finally, we compare the proposed algorithm with other state-of-the-art incomplete multi-view clustering methods on several benchmark datasets to illustrate its effectiveness.

关键词： incompleteness multi-view clustering local clustering global clustering co-regularization

Multiscale simulation of nanometric cutting of single crystal copper——effect of different cutting speeds

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Acta Metallurgica Sinica(English Letters) 2009年第6期22卷 440-446页

作者： Hongmin PEN Qingshun bai Yingchun liang Mingjun CHEN School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

A multiscale simulation has been performed to determine the effect of the cutting speed on the deformation mechanism and cutting forces in nanometric cutting of single crystal copper. The multiscale simulation model, which links the finite element method and the molecular dynamics method, captures the atomistic mechanisms during nanometric cutting from the free surface without the computational cost of full atomistic simulations. Simulation results show the material deformation mechanism of single crystal copper greatly changes when the cutting speed exceeds the material static propagation speed of plastic wave. At such a high cutting speed, the average magnitudes of tangential and normal forces increase rapidly. In addition, the variation of strain energy of work material atoms in different cutting speeds is investigated.

关键词： Multiscale simulation Nanometric cutting Single crystal copper Propagation speed of plastic wave

Effects of heat treatment on the microstructure and mechanical properties of ZA84 magnesium alloy

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Journal of University of Science and Technology Beijing 2008年第6期15卷 747-752页

作者： Mingbo Yang liang bai Fusheng Pan Hongjun Hu School of Materials Science and Engineering Chongqing Institute of Technology Chongqing 400050 China School of Materials Science and Engineering Chongqing University Chongqing 400030 China

The effects of heat treatment on the microstructure and mechanical properties of ZA84 （Mg-8Zn-4Al-0.25Mn） alloy were investigated. The results indicate that the as-cast microstructure of the alloy is mainly composed of α-Mg matrix and two different morphologies of precipitates （continuous and quasi-continuous Mg32（Al,Zn）49 phases and isolated Mg5Al2Zn2 phases）. After solid solution treatment at 345℃, the Mg32（Al,Zn）49 phases change from continuous and quasi-continuous net to disconnected acute angle shape, and parts of second phases sphericize. The optimum heat treatment condition for the alloy is solution treatment at 345℃ for 48 h and water quenching, then aging treatment at 200℃ for 12 h and atmosphere cooling. Under the optimum condition, the ulti- mate tensile strength and yield strength of the alloy can be imoroved, but the elongation is not effected much bv heat treatment.

关键词： ZA84 magnesium alloy heat treatment microstructure mechanical properties precipitates

A Fair Blind Signature Scheme to Revoke Malicious Vehicles in VANETs

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Computers, Materials & Continua 2019年第1期58卷 249-262页

作者： Xiaoliang Wang Jianming Jiang Shujing Zhao liang bai School of Computer and Communication Engineering Hunan University of Science and TechnologyXiangtan411201HunanChina School of Computer Science University of NewcastleNewcastle2308New South WalesAustralia

With the rapid development of IoT(Internet of Things),VANETs(Vehicular Ad-Hoc Networks)have become an attractive ad-hoc network that brings convenience into people’s *** can be informed of the position,direction,speed and other real-time information of nearby vehicles to avoid traffic jams and ***,VANET environments could be dangerous in the absence of security *** of the openness and self-organization of VANETs,there are plenty of malicious *** guarantee vehicle security,the research aims to provide an effective VANET security mechanism that can track malicious vehicles as ***,this work focuses on malicious vehicles and proposes an anonymous authentication scheme in VANETs based on the fair blind signature to protect vehicle security.

关键词： VANETs fair blind signature trusted third-party anonymous authentication

Activation pressure studies with an iron-based catalyst for slurry Fischer-Tropsch synthesis

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Journal of Natural Gas Chemistry 2009年第4期18卷 429-435页

作者： Qinglan Hao liang bai Hongwei Xiang Yongwang Li College of Material Science ＆ Chemical Engineering Tianjin University of Science ＆ Technology Tianjin 300457 China State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China

Fischer-Tropsch synthesis （FTS） was carried out with an industrial iron-based catalyst （100Fe/5Cu/6K/16SiO2, by weight） under the baseline conditions in a stirred tank slurry reactor （STSR）. The effects of activation pressure on the catalyst activity and selectivity were investigated. It was found that iron phase compositions, textural properties, and FTS performances of the catalysts were strongly dependent on activation pressure. The high activation pressure retards the carburization. MФssbauer effect spectroscopy （MES） results indicated that the contents of the iron carbides clearly decrease with the increase of activation pressure, especially for the activation pressure increasing from 1.0 MPa to 1.5 MPa, and the reverse trend is observed for superparamagnetic Fe^3＋（spm）. The higher content of Fe^3＋（spm） results in the higher amount of CO2 in tail gas when the catalyst is reduced at higher pressure. The catalyst activity decreases with the increase of activation pressure. The high quantity of iron carbides is necessary to obtain high FTS activity. However, the activity of the catalyst activated in syngas can not be predicted solely from the fraction of the carbides. It is concluded that activation with syngas at the lower pressure would be the most desirable for the better activity and stability on the iron-based catalyst.

关键词： wFischer-Tropsch synthesis spray-dried iron catalyst activation pressure slurry reactor MCssbauer effect spectroscopy

Effects of Sr on the microstructure,tensile and creep properties of AZ61-0.7Si magnesium alloy

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 89-95页

作者： Ming-bo Yang Jia Shen liang bai Fu-sheng Pan Materials Science and Engineering College Chongqing Institute of Technology Chongqing 400050 China Materials Science and Engineering College Chongqing University Chongqing 400030 China

The modification and refinement of Mg2Si phase is thought to be one of the key aspects to improve the mechanical properties of Si-containing magnesium alloys. In this article, the effects of Sr on the microstructure, tensile and creep properties of AZ61-0.7Si magnesium alloy were investigated. The results indicate that adding small amounts of Sr to AZ61-0.7Si alloy can modify and refine Chinese script shaped Mg2Si phases in the alloy. After adding 0.03wt%-0.09wt% Sr to AZ61-0.7Si alloy, the Mg2Si phases in the alloy change from the coarse Chinese script shape to fine granule and/or irregular polygonal shapes. The modification and refinement mechanisms of Mg2Si phases in Sr-containing AZ61-0.7Si alloys are possibly related to the reduction of growth rate and the enhancement of nucleation ratio for Mg2Si particles during the solidification process. Owing to the modification and refinement of Mg2Si phases, the tensile and creep properties of Sr-containing AZ61-0.7Si alloys are greatly improved.

关键词： magnesium alloy Mg2Si phase Sr addition mechanical properties microstructure

POSITIVE SOLUTIONS FOR SOME 1-DIMENSIONAL BOUNDARY VALUE PROBLEMS OF LAPLACE-TYPE

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Applied Mathematics(A Journal of Chinese Universities) 2007年第1期22卷 13-20页

作者： bai Zhanbing liang Xiangqian Li Weiming Institute of Mathematics Shandong University of Science and Technology Qingdao 266510 China

This paper deals with the existence of triple positive solutions for the 1-dimensional equation of Laplace-type （φ（x′（t）））′＋q（t）f（t,x（t）,x′（t））=0,t∈（0,1）,subject to the following boundary condition：a1φ（x（0））-a2φ（x＇（0））=0,a3φ（x（1））＋a4φ（x＇（1））=0,where φ is an odd increasing homogeneous homeomorphism. By using a new fixed point theorem, sufficient conditions are obtained that guarantee the existence of at least three positive solu- tions. The emphasis here is that the nonlinear term f is involved with the first order derivative explicitly.

关键词： triple positive solution equation of Laplace-type boundary value problem fixed point theorem.

A Novel Anonymous Authentication Scheme Based on Edge Computing in Internet of Vehicles

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Computers, Materials & Continua 2021年第6期67卷 3349-3361页

作者： Xiaoliang Wang Xinhui She liang bai Yang Qing Frank Jiang Hunan University of Science and Technology Xiangtan411201China Hunan University Changsha410006China School of Information Technology Deakin UniversityGeelong3220Australia

The vehicular cloud computing is an emerging technology that changes vehicle communication and underlying trafc management ***,cloud computing has disadvantages such as high delay,low privacy and high communication cost,which can not meet the needs of realtime interactive information of Internet of *** security and privacy in Internet of Vehicles is also regarded as one of its most important ***,in order to ensure the user information security and improve the real-time of vehicle information interaction,this paper proposes an anonymous authentication scheme based on edge *** this scheme,the concept of edge computing is introduced into the Internet of vehicles,which makes full use of the redundant computing power and storage capacity of idle edge *** edge vehicle nodes are determined by simple algorithm of dening distance and resources,and the improved RSA encryption algorithm is used to encrypt the user *** improved RSA algorithm encrypts the user information by reencrypting the encryption *** with the traditional RSA algorithm,it can resist more attacks,so it is used to ensure the security of user *** can not only protect the privacy of vehicles,but also avoid anonymous *** results show that the proposed scheme has lower computational complexity and communication overhead than the traditional anonymous scheme.

关键词： Cloud computing anonymous authentication edge computing anonymity abuse

Control over Mechanical Properties and Microstructure of BR1500HS Hot-stamped Parts

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Journal of Iron and Steel Research International 2014年第6期21卷 606-613页

作者： bai-liang ZHUANG Zhong-de SHAN Chao JIANG Xin-ya LI State Key Laboratory of Advanced Forming Technology and Equipment of CAM Jiangsu Institute China Academy of Machinery Science and Technology

The hot stamping processing parameters are of critical importance in transforming ultra-high-strength steel （UHSS） into high-quality parts, which were studied by mechanical properties tests, metallographic observations and calculation analysis method based on hot stamping experiments and numerical simulation technology, the mechanical properties, thickness, dimensional accuracy, and microstructure of the hot formed parts are analyzed to determine the influence of different processing parameters for UHSS parts formed from BR1500HS. The results indicate that the quenching time had the most significant impact on the mechanical properties of the parts, and longer quenching time resulted in better mechanical properties. In addition, the pressing speed had a significant influence on the thick ness of the formed parts, and the part-opening temperature had the most significant effect on the dimensional accura cy of the parts. And to get hot stamped parts with excellent quality, the optimum process conditions should be set as heating temperature of 930 ℃, soaking time of 4 min, stamping force of 7 MPa, pressing speed of 75 mm/s, quench ing time of 15 s, and water-flow rate of 1.1 m/s.

关键词： hot forming processing parameter mechanical property microstructure