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AInvR:Adaptive Learning Rewards for Knowledge Graph Reasoning Using Agent Trajectories

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Tsinghua Science and Technology 2023年第6期28卷 1101-1114页

作者： Hao Zhang Guoming Lu ke qin Kai Du School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Multi-hop reasoning for incomplete Knowledge Graphs(KGs)demonstrates excellent interpretability with decent *** Learning(RL)based approaches formulate multi-hop reasoning as a typical sequential decision *** intractable shortcoming of multi-hop reasoning with RL is that sparse reward signals make performance *** mainstream methods apply heuristic reward functions to counter this ***,the inaccurate rewards caused by heuristic functions guide the agent to improper inference paths and unrelated object *** this end,we propose a novel adaptive Inverse Reinforcement Learning(IRL)framework for multi-hop reasoning,called AInvR.(1)To counter the missing and spurious paths,we replace the heuristic rule rewards with an adaptive rule reward learning mechanism based on agent’s inference trajectories;(2)to alleviate the impact of over-rewarded object entities misled by inaccurate reward shaping and rules,we propose an adaptive negative hit reward learning mechanism based on agent’s sampling strategy;(3)to further explore diverse paths and mitigate the influence of missing facts,we design a reward dropout mechanism to randomly mask and perturb reward parameters for the reward learning *** results on several benchmark knowledge graphs demonstrate that our method is more effective than existing multi-hop approaches.

关键词： Knowledge Graph Reasoning(KGR) Inverse Reinforcement Learning(IRL) multi-hop reasoning

The MADS-box transcription factor CmAGL11 modulates somatic embryogenesis in Chinese chestnut(Castanea mollissima Blume)

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Journal of Integrative Agriculture 2020年第4期19卷 1033-1043页

作者： GAO Yue-rong SUN Jia-chen SUN Zhi-lin XING Yu ZHANG qing FANG ke-feng CAO qing-qin qin ling Beijing Advanced Innovation Center for Tree Breeding by Molecular Design Beijing University of AgricultureBeijing 102206P.R.China Beijing Bei Nong Enterprise Management Co. Ltd.Beijing 102206P.R.China College of Plant Science and Technology Beijing Key Laboratory for Agricultural Application and New TechniqueBeijing University of AgricultureBeijing 102206P.R.China Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees Beijing University of AgricultureBeijing 102206P.R.China

Somatic embryogenesis(SE)is an effective approach of in vitro regeneration that depends on plant cell ***,largely unknown of molecular mechanisms of SE in woody plants such as Chinese chestnut(Castanea mollissima Blume),limits the development of the woody plant ***,we report the MADS-box transcription factor Cm AGL11 in Chinese *** AGL11 transcripts specifically accumulated in the globular *** of Cm AGL11 in chestnut callus enhanced its SE capacity,and the development of somatic embryos occurred significantly faster than in the ***-seq results showed that Cm AGL11 affects the expression of several genes related to the gibberellin,auxin,and ethylene ***,the analysis of DNA methylation status indicated that the promoter methylation plays a role in regulation of Cm AGL11 expression during *** results demonstrated that Cm AGL11 plays an important role in the SE process in Chinese chestnut,possibly by regulating gibberellin,auxin,and ethylene *** will help establish an efficient platform to accelerate genetic improvement and germplasm innovation in Chinese chestnut.

关键词： Chinese chestnut CmAGL11 somatic embryogenesis DNA methylation

New Results on Nonexistence of Perfect p-Ary Sequences and Almost p-Ary Sequences

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Acta Mathematica Sinica,English Series 2016年第1期32卷 2-10页

作者： Hai Ying LIU ke qin FENG School of Mathematical Sciences Peking University Department of Mathematical Sciences Tsinghua University

Complex periodical sequences with lower antocorrelation values are used in CDMA comnmnieation systems and cryptography. In this paper we present new nonexistence results on perfect p-ary sequences and almost p-ary seq... 详细信息

关键词： Perfect sequence p-ary and almost p-ary sequence difference set cyclotomic field imag-inary quadratic field

Formation of carbonitride precipitates in hardfacing alloy with niobium addition

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Rare Metals 2013年第1期32卷 52-56页

作者： ke Yang qin Yang Ye-Feng Bao College of Mechanical and Electrical Engineering Hohai University

Niobium, as the most effective second-phase forming element, was added in the Fe-Crl3-C-N hard- facing alloy to get carbonitride precipitates. Morphology and composition of carbonitride in the hardfacing alloy were studied by optical microscopy, scanning electron microscopy, and electron probe microanalyzer. The ther- modynamics and the effect on the matrix of the formation of carbonitride were also discussed. It was found that niobium carbonitrides are complex Nb（C, N） precipitate distributed on grain boundary and matrix of the hardfacing alloy. Under as-welded condition, primary carbonitride particles were readily precipitated from the hardfacing alloy with large size and morphology as they were formed already during solidification. Under heat treatment condi- tion, a large number of secondary carbonitrides can pre- cipitate out with very fine size and make a great secondary hardening effect on the matrix. As a result, addition of niobium in the hardfacing alloy can prevent the formation of chromium-rich phase on grain boundaries and inter- granular chromium depletion.

关键词： Niobium Carbonitride Hardfacing alloy Precipitate

Effect of chlorine content of chlorophenols on their adsorption by mesoporous SBA-15

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Journal of Environmental Sciences 2012年第8期24卷 1411-1417页

作者： qingdong qin ke Liu Dafang Fu Haiying Gao School of Civil Engineering Southeast UniversityNanjing 210096China Department of Man-Machine and Environment Engineering Nanfing University of Aeronautics and AstronauticsNanfing 210016China

Studies on the effect of the chlorine content of chlorophenols （CPs） on their adsorption from aqueous solution by mesoporous SBA-15 are important in understanding the mechanisms of CP adsorption. In this study, three CPs with different degrees of chlorine content （i.e., 2-chlorophenol, 2,6-dichlorophenol and 2,4,6-trichlorophenol） were investigated. The effects of parameters such as temperature and solution pH were studied. The results showed that CP adsorption by SBA- 15 increased with increasing number of chlorine substituents and depended strongly on the temperature and solution pH. Thermodynamic parameters such as Gibbs free energy change （AGO）, enthalpy change （△H^0） and entropy change （△S^0） were also calculated. By comparison of the adsorption coefficient of CPs with varying physical-chemical properties （size, hydrophobicity and electron density）, we propose that hydrophobic interactions between CPs and the SBA-15 surface, as well as electron donor-acceptor （EDA） complexes between oxygen of the siloxane surface of SBA-15 （e--donor） and the n-system of the CPs （e--acceptor）, were dominant adsorption mechanisms.

关键词： chlorophenols mesoporous SBA-15 adsorption pH temperature

A new robust design for imperfection sensitive stiffened cylinders used in aerospace engineering

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Science China(Technological Sciences) 2015年第5期58卷 796-802页

作者： LIANG ke ZHANG YongJie SUN qin RUESS Martin School of Aeronautics Northwestern Polytechnical University Qian Xuesen Laboratory of Space Technology China Aerospace Science and Technology Corporation Faculty of Aerospace Engineering Delft University of Technology

A knock-down factor is commonly used to take into account the obvious decline of the buckling load in a cylindrical shell caused by the inevitable imperfections. In 1968, NASA guideline SP-8007 gave knock-down factors which rely on a lower-bound curve taken from experimental data. Recent research has indicated that the NASA knock-down factors are inclined to produce very conservative estimations for the buckling load of imperfect shells, due to the limitations of the computational power and the experimental skills available five decades ago. A novel knock-down factor is proposed composed of two parts for the metallic stiffened cylinders. A deterministic study is applied to achieve the first part of the knock-down factor considering the measured geometric imperfection, the other types of imperfections are considered in the second part using a stochastic analysis. A smeared model is used to achieve the implementation of the measured geometric imperfection for the stiffened cylinder. This new robust and less conservative design for the stiffened cylinders is validated by using test results.

关键词： cylinders buckling conservative shells stochastic inevitable validated imperfect deterministic metallic

linear stability of plane creeping Couette flow for Burgers fluid

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Acta Mechanica Sinica 2013年第1期29卷 12-23页

作者： Kai-Xin Hu Jie Peng ke-qin Zhu Department of Engineering Mechanics Tsinghua University

It is well known that plane creeping Couette flow of UCM and Oldroy-B fluids are linearly stable. However, for Burges fluid, which includes UCM and Oldroyd-B fluids as special cases, unstable modes are detected in the present work. The wave speed, critical parameters and perturbation mode are studied for neutral waves. Energy analysis shows that the sustaining of perturbation energy in Poiseuille flow and Couette flow is completely different. At low Reynolds number limit, analytical solutions are obtained for simpli- fied perturbation equations. The essential difference between Burgers fluid and Oldroyd-B fluid is revealed to be the fact that neutral mode exists only in the former.

关键词： linear stability theory Burgers fluid Creeping Couette flow - Elastic instability

A new composite material produced by semi-continuous casting

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Acta Metallurgica Sinica(English Letters) 2010年第4期23卷 255-260页

作者： Huixue JIANG ke qin Haitao ZHANG Jianzhong CUI key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University Shenyang 110819 China

A new composite material consisting of lxxx aluminum alloy and 7xxx aluminum alloy was produced by semi-continuous casting. Macrostructure, microstructure, composition distribution and hardness distribution of composite interface were analyzed. Macrostructure shows that composite interface is planar and clean with little evidence of porosity; microstructure shows that composite interface is a kind of metallurgical bonding; composition and hardness distributions have a good corresponding relationship. At the same time, the mechanical property of composite interface was measured, the tensile strength is 71 MPa, the shearing strength is 62 MPa and the bending strength is 142.5 MPa, which can also show that composite interface is a kind of metallurgical bonding. Temperature distribution of composite interface was obtained by measuring temperatures near composite interface in lxxx aluminum alloy.

关键词： Composite material lxxx aluminum alloy 7xxx aluminum alloy Semi-continuous casting

The axisymmetric long-wave interfacial stability of core-annular flow of power-law fluid with surfactant

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Acta Mechanica Sinica 2012年第1期28卷 24-33页

作者： Xue-Wei Sun Jie Peng ke-qin Zhu Department of Engineering Mechanics Tsinghua University100084 BeijingChina

The long wave stability of core-annular flow of power-law fluids with an axial pressure gradient is investigated at low Reynolds number. The interface between the two fluids is populated with an insoluble surfactant. The analytic solution for the growth rate of perturbation is obtained with long wave approximation. We are mainly concerned with the effects of shear-thinning/thickening property and interfacial surfactant on the flow stability. The results show that the influence of shear-thinning/thickening property accounts to the change of the capillary number. For a clean interface, the shear-thinning property enhances the capillary instability when the interface is close to the pipe wall. The converse is true when the interface is close to the pipe centerline. For shear-thickening fluids, the situation is reversed. When the interface is close to the pipe centerline, the capillary instability can be restrained due to the influence of surfactant. A parameter set can be found under which the flow is linearly stable.

关键词： Core-annular flow. Power-law fluid. Interfacial surfactant Long-wave stability