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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

Uniqueness and local stability for the inverse scattering problem of determining the cavity

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Science china mathematics 2005年第8期48卷 1113-1123页

作者： FENG Lixin & ma Fuming lmam, school of mathematical sciences, Peking University, {3. 100871,{4. school of mathematical sciences, Heilongjiang University, Harbin 150080,{4. school of mathematical sciences, Jilin University, Changchun 13.012,{4. 1. lmam School of Mathematical Sciences Peking University 100871 Beijing China 2. school of mathematical sciences Heilongjiang University 150080 Harbin China 3. school of mathematical sciences Jilin University 130012 Changchun China

Considering a time-harmonic electromagnetic plane wave incident on an arbitrarily shaped open cavity embedded in infinite ground plane, the physical process is modelled by maxwell's equations. We investigate the inverse problem of determining the shape of the open cavity from the information of the measured scattered field. Results on the uniqueness and the local stability of the inverse problem in the 2-dimensional TM (transverse magnetic) polarization are proved in this paper.

关键词： uniqueness, stability, maxwell's equations, inverse scattering problem.

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3. SHI Yuruo3.& MIAO Laicheng4.1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 51064., china 2. Graduate University of Chinese Academy of sciences, {3. 10003., china 3. SHRIMP isotope Laboratory, Chinese Academy of Geological sciences, {3. 10003., china 4. Institute of Geology and Geophysics, Chinese Academy of sciences, {3. 100029, china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of Chinese Academy of sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-13.) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/23.U ages of 229.4.± 3.0 ma and 23..4.± 3.6 ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the manghuai Formation give a weighted mean 206Pb/23.U age of 23..0 ± 5.0 ma. These data suggest that the igneous rocks from the Lincang granitic batholith and manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~23. ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/23.U apparent age of 1977±4. ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, manghuai Formation rhyolite, southern Lancangjiang.

TRANSPORTATION INEQUALITIES FOR WEAKLY DEPENDENT SEQUENCES

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Acta mathematica Scientia 2011年第4期31卷 1494-1502页

作者：马宇韬 school of mathematical sciences Beijing Normal University

In [3., they gave necessary and sufficient condition for T 1 C and then as applications T 1 C for weakly dependent sequences was established. In this note, based on Gozlan-L′eonard characterization for W 1 H -inequal... 详细信息

关键词： W 1 H inequality T p (C)-inequality weakly dependent sequences tensorization

Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2, LI Anchun1, HU Ningjing2,3. FU Yongtao1& ma Zhibang4.1. Institute of Oceanology, Chinese Academy of sciences, Qingdao 266071, china 2. Graduate {3. of the Chinese Academy of sciences, beijing 10003., china 3. Institute of Soil Science, Chinese Academy of sciences, Nanjing 210008, china 4. Institute of Geology and Geophysics, Chinese Academy of sciences, beijing 100029, china 1. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate school of the Chinese Academy of sciences Beijing 100039 China 3. Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China 4. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREma source area under the Okinawa Trough. magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

Analytical model of vertical load acting on jacked pipe considering soil arching effect in cohesionless soil

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Underground Space 2024年第1期14卷 263-284页

作者： Yu Zhang Lianjin Tao Xu Zhao Jun Liu Weizhang Liao Fei Guo Xiaohui Yang ruiqin Zhong beijing Advanced Innovation Center for Future Urban Design Beijing University of Civil Engineering and ArchitectureBeijing 102627China The Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100024China beijing Municipal Construction Group Co. LtdBeijing 100045China beijing Municipal Engineering Institute Beijing 100037China

For the project of pipe jacking in cohesionless soil,it is key to determine the vertical load on jacked pipe so as to predict the jacking force *** this paper,a new parabolic soil arching model was proposed to calculate the vertical load on jacked *** proposed analytical model was composed of parabolic soil arching zone,parabola-typed collapse zone and friction arch *** with existing literature,the key parameters(i.e.,height of parabolic soil arching,horizontal pressure coefficient and width and height of friction arch)were *** addition,considering that the trajectory of major stress is parabola,the formula of horizontal pressure coefficient was deduced in the friction *** parabolic soil arching zone is assumed as a three-hinged arch with reasonable arch axis,and the formula of load transfer was derived considering the transition effect of parabolic soil *** results of experiment,theoretical models and numerical model were adopted to verify the proposed analytical ***,the influence of the key parameters on the vertical load on jacked pipe were also discussed in *** work provides a meaningful reference for evaluating the vertical load on jacked pipe for design of pipe jacking.

关键词： Jacked pipe Soil arching effect Theoretical model Parabolic soil arching model Vertical load

Birth-death processes on trees

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Science china mathematics 2010年第11期53卷 2993-3004页

作者： ma YuTao school of mathematical sciences & Laboratory of mathematics and Complex Systems, {4. Normal University, {4. 100875,{3. 1. school of mathematical sciences & Laboratory of mathematics and Complex Systems Beijing Normal University Beijing 100875 China

In this paper, we consider birth-death processes on a tree T and we are interested when it is regular, recurrent and ergodic (strongly, exponentially). By constructing two corresponding birth death processes on Z+, we obtain computable conditions sufficient or necessary for that (in many cases, these two conditions coincide). With the help of these constructions, we give explicit upper and lower bounds for the Dirichlet eigenvalue λ0. At last, some examples are investigated to justify our results.

关键词： birth-death process tree ergodicity Dirichlet eigenvalue

Split-plot designs with general minimum lower-order confounding

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Science china mathematics 2010年第4期53卷 939-952页

作者： WEI JiaLin 1,4.YANG JianFeng 1,LI Peng 3.& ZHANG RunChu 1,2,1 school of mathematical sciences and LPMC,Nankai University,Tianjin 3.0071,china 2 KLAS and {4. of {3.the{3.tics and Statistics,Northeast Nor{3.l University,Changchun 13.024.china 3.0},Capital Nor{3.l University,beijing 10003.,china 4.{4. of sciences,Tianjin University of Commerce,Tianjin 3.013.,china 1. school of mathematical sciences and LPMC Nankai University Tianjin 300071 China4. School of Sciences Tianjin University of Commerce Tianjin 300134 China3. School of Mathematical Sciences Capital Normal University Beijing 100037 China2. KLAS and School of Mathematics and Statistics Northeast Normal University Changchun 130024 China

Split-plot designs have been widely used in industrial *** to now,most methods for choosing this kind of designs are based on the minimum aberration (ma) ***,by introducing a new pattern,called aliased effect-number pattern (AENP),Zhang et *** a general minimum lowerorder confounding (denoted by GMC for short) criterion and established a general minimum confounding (also denoted by GMC for saving notations) *** is proved that,the GMC criterion selects optimal designs in a more elaborate manner than the existing ones,and when an experimenter has a prior about the importance ordering of factors in experiments the GMC designs are better than other optimal *** this paper we extend the GMC criterion to the split-plot design case and give a GMC-FFSP criterion for ranking split-plot *** comparisons of the new criterion with the ma-MSA-FFSP criterion are given,and the optimal 3.-run split-plot designs up to 14.factors under the two criteria are tabulated for comparison and application.

关键词： fractional factorial design GMC criterion minimum aberration split-plot

Upper bound and formula for class numbers of abelian function fields

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Progress in Natural Science:materials International 2006年第3期16卷 321-323页

作者： ma Lianrong and ZHANG Xianke (Department of mathematical sciences, Tsinghua University, {3. 100084.{4.) Department of mathematical sciences Tsinghua University Beijing 100084 China

For any abelian function field K (i.e. any subfield of a cyclotomic function field L=k (∧P) over the rational function field k ) with conductor being an irreducible polynomial over a finite field of odd characteristic, by studying the Carlitz-module structure and the character group of K, an explicit upper bound and a calculating formula of the relative divisor class number h- (K) of K are given. Our calculated results of K develop Rosen’s recent results of L .

关键词： Carlitz module cyclotomic function field class number character abelian function field.