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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

Magnetic order in Cr_(73.7)(Fe_(0.83)Mn_(0.17))_(26.3)alloy

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Chinese Science Bulletin 1997年第4期42卷 282-285页

作者： XU WeimingCryogenic laboratory, Chinese Academy of Sciences, beijing 100080, china Cryogenic laboratory Chinese Academy of Sciences Beijing China

WITH the temperature decreasing, Cr100-xFex（18≤x≤25） alloys exhibit first a transition from a paramagnetic （PM） state to a ferromagnetic （FM） state and then a second transition from the FM state to a re-entran... 详细信息

关键词： Mossbauer spectrum magnetic order clusters re-entrant spin glass.

Modulated Quasi-plane Tunneling Current

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 44-46页

作者： Peng Feng Wenmin Dai (china Center of Advanced Science & Technology (world laboratory ) P.O. Box 8730, beijing 100080, china)(Applied Science School, University of Science and Technology beijing, beijing 100083, china) china Center of Advanced Science and Technology (world laboratory) P.O. Box 8730 Beijing 100080 China Applied Science School University of Science and Technology Beijing Beijing 100083 China

A new tutmeling junction can be formed by an insulator layer inserting into a quantum well, and in the quantum well, a quasi-plane tunneling current can be formed by applying a tunneling voltage. If a P-N junction is grown on the quantum well, the tunneling current can be modulated by a P-N junction-bias voltage. The modulated quasi-plane tunneling current is not only related to the bias voltage, but also to the depth of the quantum well. It is analyzed that the P-N junction-bias voltage how to affect the tunneling current and a method of measuring the depth of the quantum well is presented.

关键词： quantum well tunneling current semiconductor device

CORRECTION METHODS FOR STEADY INCOMPRESSIBLE FLOWS

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Journal of Computational Mathematics 1999年第4期17卷 419-424页

作者： Jian Li(State Key laboratory of Scientific and Engineering Computing, ICMSEC, Chinese Academy of Sciences, beijing 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京

Correction methods for the steady semi-periodic motion of incompressible fluid are investigated. The idea is similar to the influence matrix to solve the lack of vorticity boundary conditions. For any given boundary condition of the vorticity, the coupled vorticity-stream function formulation is solved. Then solve the governing equations with the correction boundary conditions to improve the solution. These equations are numerically solved by Fourier series truncation and finite difference method. The two numerical techniques are employed to treat the non-linear terms. The first method for small Reynolds number R equals 0-50 has the same results as that in M. Anwar and S.C.R. Dennis' report. The second one for R greater than 50 obtains the reliable results. (Author abstract) 4 Refs.

关键词： incompressible flow vorticity stream function numerical solution

Nondegenerative ML-sequences over ring Z/(2~e)

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Chinese Science Bulletin 1999年第17期44卷 1557-1561页

作者： YANG Junhui and ZHAI QibinInstitute of Software , Chinese Academy of Sciences , beijing 100080, china State Key laboratory of Information Security , beijing 100080, china Chinese Acad Sci Inst Software Beijing 100080 Peoples R China State Key Lab Informat Secur Beijing 100080 Peoples R China

The so-called quasi-period of an ML-sequence has been introduced. It is noted that an ML-sequence may degenerate in the sense that it has the quasi-period shorter than its period, and the problem of constructing the n... 详细信息

关键词： nondegenerate ML-sequence quasi-period.

How random are matrix elements of the nuclear shell model Hamiltonian?

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1477-1481页

作者： SHEN JiaJie1 & ZHAO YuMing1,2,3,4 1 Department of Physics,Shanghai Jiao Tong University,Shanghai 200240,china 2 Center of Theoretical Nuclear Physics,National laboratory of Heavy Ion Accelerator,Lanzhou 730000,china 3 Nishina Center,Institute of Physical Chemical Research(RIKEN),Hirosawa 2-1,Wako-shi,Saitama 351-0198,Japan 4.ccast,world laboratory,beijing 100080,china Department of Physics Shanghai Jiao Tong University Shanghai 200240 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China Nishina Center Institute of Physical Chemical Research (RIKEN) Hirosawa 2-1 Wako-shi Saitama 351-0198 Japan world laboratory CCAST Beijing 100080 China

In this paper we study the general behavior of matrix elements of the nuclear shell model *** find that nonzero off-diagonal elements exhibit a regular pattern,if one sorts the diagonal matrix elements from smaller to larger *** correlation between eigenvalues and diagonal matrix elements for the shell model Hamiltonian is more remarkable than that for random matrices with the same distribution unless the dimension is small.

关键词： nuclear shell model geometry property linear correlation randomize

NONCONFORMING FINITE ELEMENT APPROXIMATIONS TO THE UNILATERAL PROBLEM

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Journal of Computational Mathematics 1999年第1期17卷 15-24页

作者： Lie-heng Wang(State Key laboratory of Scientific and Engeneering Computing, ICMSEC,Chinese Academy of Sciences, beijing 100080, china) Chinese Acad Sci State Key Lab Sci & Engn Comp ICMSEC Beijing 100080 Peoples R China

The nonconforming finite element (two Crouzeix-Raviart linear elements and Wilson element) approximations to the unilateral problem are considered. The error bounds for these elements are obtained in the appropriate a... 详细信息

关键词： unilateral problem nonconforming finite element

Asymptotic behavior of the divergence on loop spaces over a compact Riemannian manifold

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Chinese Science Bulletin 1998年第4期43卷 272-274页

作者： LI Xiangdong Probability laboratory, Institute of Applied Mathematics, Chinese Academy of Sciences, beijing 100080, china Probability laboratory Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

The asymptotic behavior of the divergence on loop space is studied over a compact Riemannian manifold via quasi_sure analysis. A Sobolev estimate plays a crucial role.

关键词： divergence exponential integrability Sobolev estimate.

The gravity wave instability induced by photochemistry in summer polar mesopause region

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Chinese Science Bulletin 2000年第3期45卷 267-272页

作者： Center for Space Science and Applied Research, Chinese Academy of Sciences, beijing 100080, china laboratory of Numeric Study of Heliospheric Physics, Chinese Academy of Sciences, beijing 100080, china Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China laboratory of Numeric Study of Heliospheric Physics Chinese Academy of Sciences Beijing China

The effect of diabatic process due to the photochemical heating and cooling on the gravity wave propagation in middle atmosphere is studied. A linear gravity wave model which considers the diabatic process is established. The unstable region and the growth rate of the gravity wave caused by photochemistry are calculated. And the comparison between the model and the adiabatic gravity wave theory of pure dynamics is made. The results indicate that the photochemical heating process can induce the instability of gravity wave at mesopause. The intensity of the instability becomes stronger as the temperature decreases. The temperature feature and the altitude characteristics of the instability are consistent with the observation. Therefore, the instability of the gravity wave induced by photochemistry may be an important mechanism in polar mesopause region in summer.

关键词： photochemistry instability gravity wave growth rate.