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Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma School of Computer Science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-20M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,university of Science and technology beijing,beijing 100083,{4.

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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei university of Science and technology beijing,beijing,{4.

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 4.°plane due to the general corrosion in aqueous solution with high NH_4.H concentra- tion,while stress corroded in aqueous solution with low NH_4.H concentration, numerous cracks with spacings of 10—150μm were found on the 4.°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

Application of mesoscale modeling optimization to development of advanced materials

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Progress in Natural Science:Materials International 2004年第8期14卷 8-15页

作者： SONG Xiaoyan(School of Materials Science and Engineering, beijing university of technology, beijing 100022,{4.) beijing Univ Technol Sch Mat Sci & Engn Beijing 100022 Peoples R China

The rapid development of computer modeling in recent years offers opportunities for materials preparation in a more economic and efficient way. In the present paper, a practicable route for research and development of advanced materials by applying the visual and quantitative modeling technique on the mesoscale is introduced. A 3D simulation model is developed to describe the microstructure evolution during the whole process of deformation, recrystallization and grain growth in a material containing particles. In the light of simulation optimization, the long-term stabilized fine grain structures ideal for high-temperature applications are designed and produced. In addition, the feasibility, reliability and prospects of material development based on mesoscale modeling are discussed.

关键词： mesoscale computer simulation Monte Carlo technique deformation recrystallization grain growth.

Effects of Surface-Active Elements Sulfur on Flow Patterns of Welding Pool

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Journal of Materials Science & technology 2005年第3期21卷 408-414页

作者： Yuzhen ZHAO, Yongping LEI and Yaowu SHI School of Materials Science and Engineering, beijing university of technology, beijing 100022,{4. School of Materials Science and Engineering Beijing University of Technology Beijing 100022 China

A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc (GTA) welding pool with different sulfur concentrations. It has been shown that, the weld penetration increases sharply with increasing sulfur content. When sulfur content increases beyond 80 × 10-6, the increase in sulfur content does not have an appreciable difference on the welding pool size and shape, and the depth/width remains constant. Sulfur changes the temperature dependence of surface tension coefficient from a negative value to a positive value and causes significant changes on flow patterns. The increase in soluble sulfur content and the decrease at free surface temperature can extend the region of positive surface tension coefficient. As sulfur content exceeds 125×10-6, the sign of surface tension coefficient is positive. Depending upon the sulfur concentrations, three, one or two vortexes that have different positions, strength and directions may be found in the welding pool. The contrary vortexes can efficiently transfer the thermal energy from the arc, creating a deep welding pool. An optimum range of sulfur content is 20-150×10-6.

关键词： Surface-active elements Sulfur Plow patterns Depth/width

The Dissymmetry of Friction Stir Welding Joints and Va-riable Polarity Plasma Arc Welding Joints Study

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稀有金属材料与工程 2011年第S4期40卷 84-89页

作者： Chen Shujun,Wang Long,Yu Yang beijing university of technology Mechanical Engineering,beijing{4.,china beijing Univ Technol Mech Engn Beijing 100022 Peoples R China

2219 aluminum alloys welding joints were prepared by Friction stir welding (FSW) and Variable polarity plasma arc welding (VPPAW).The microstructure of joints was characterized by means of OM,SEM,and *** measurements was performed to differentiate the joint zones and to evaluate the symmetry level of the joints with the help of nano-indentation *** dissymmetry of microstructure and mechanical properties was found both in FSW joint and VPPAW *** dissymmetry in FSW joint can not be suppressed due to the nature of the mixing head,but the symmetry and satisfactory welding joint can be obtained by changing the working pattern of VPPAW.

关键词： FSW VPPAW nano-indentation experiment "Half-leaf" zone dissymmetry

Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4.5 1 College of Computer Science and technology,beijing university of technology,beijing 100022,china 2 State Key Laboratory of Information Security (Graduate university of the Chinese Academy of Sciences),beijing 10004.,china 3 School of Science,beijing university of Posts and Telecommunications,beijing 100876,china 4.Institute of Electronic technology,Information Engineering university,Zhengzhou 4.0004.china 5 Trusted Computing Laboratory,beijing university of technology,beijing 100022,china College of Computer Science technology Beijing University of Technology Beijing 100022 China State Key Laboratory of Information Security [Graduate university of the Chinese Academy of Sciences] Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

An efficient quantum secret sharing protocol with orthogonal product states

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2, WEN QiaoYan3 & ZHU FuChen4.1 School of Computer, beijing university of technology, beijing 100022,{4. 2 State Key Laboratory of Information Security, Graduate university of Chinese Academy of Sciences, beijing 100022,{4. 3 School of Science, beijing university of Posts and Telecommunications, beijing 100876,{4. 4.National Key Laboratory for Modern Communications, Chengdu 61004.,{4. 1. School of Computer Beijing University of Technology Beijing 100022 China 2. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100022 China 3. School of Science Beijing University of Posts and Telecommunications Beijing 100876 China 4. National Key Laboratory for Modern Communications Chengdu 610041 China

An efficient quantum secret sharing protocol with orthogonal product states in the 33 Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

Applicability of mass action law to sulphur distribution between slag melts and liquid iron

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Journal of university of Science and technology beijing 2002年第2期9卷 90-98页

作者： Jian Zhang Metallurgy School, university of Science and technology beijing, beijing 100083,{4. Metall. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

According to the mass action law and the coexistence theory of slagstructure, the calculating models of mass action concentration for CaO-MgO-FeO-Fe_2O_3-SiO_2,CaO-MgO-MnO-FeO-Fe_2O_3-P_2O_5-SiO_2 and CaO-MgO-MnO-FeO-Fe_2O_3-Al_2O_3-P_2O_5-SiO_2 slag melts areformulated and sulphur distribution between the slag melts and liquid iron is treated. It is foundthat CaO, MnO and FeO promote desulphurization, while MgO is detrimental to desulphurization. Inaddition, the sulphur distribution coefficients between the slag melts and liquid iron andpresented.

关键词： mass action law coexistence theory of slag structure activity massaction concentration

Carbon Solubility and Mass Action Concentrations of Fe-Cr-C Melts

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 86-91页

作者： Jtan Zhang(Metallurgy School, university of Science and technology beijing, beijing 100083,{4.) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

An empirical equation of carbon solubility in Fe-Cr-C melts is regressed based on the experimental data from references. Acalculating model of mass action concentrations for these melts is formulated on the basis of the coexistence theory of metaIlic melts in-volving compound formation, the phase diagram of Cr-C system as well as thermodynamic data of Fe-Cr-C melts. According to the mod-el, the standard Gibbs free energies of formation of CrC and Cr3C2 are obtained. Satisfactory agreement between the calculated and me-asured values shows that the model can reflect the structural characteristics of Fe-Cr-C melts.

关键词： activity, coexistence theory mass action concentration saturated state