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Meta-path reasoning of knowledge graph for commonsense question answering

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Frontiers of Computer Science 2024年第1期18卷 49-59页

作者： Miao ZHANG Tingting he Ming DONG National Engineering Research Center for E-Learning Central China Normal UniversityWuhan 430079China Hubei Provincial Key Laboratory of Artificial Intelligence and Smart Learning Central China Normal UniversityWuhan 430079China National Language Resources Monitoring&Research Center for Network Media Central China Normal UniversityWuhan 430079China School of Computer Central China Normal UniversityWuhan 430079China

Commonsense question answering(CQA)requires understanding and reasoning over QA context and related commonsense knowledge,such as a structured Knowledge Graph(KG).Existing studies combine language models and graph neural networks to model ***,traditional knowledge graph are mostly concept-based,ignoring direct path evidence necessary for accurate *** this paper,we propose MRGNN(Meta-path Reasoning Graph Neural Network),a novel model that comprehensively captures sequential semantic information from concepts and *** MRGNN,meta-paths are introduced as direct inference evidence and an original graph neural network is adopted to aggregate features from both concepts and paths *** conduct sufficient experiments on the CommonsenceQA and OpenBookQA datasets,showing the effectiveness of ***,we conduct further ablation experiments and explain the reasoning behavior through the case study.

关键词： question answering knowledge graph graph neural network meta-path reasoning

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen Jian-Jun he Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)he,^(4)he,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)he,d(d,p)t,d(p,γ)^(3)he,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) he *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Study on a semi-resolved CFD-DEM method for rod-like particles in a gas-solid fluidized bed

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Particuology 2024年第4期87卷 20-36页

作者： Liping he Zhengxian Liu Yongzhi Zhao Department of Mechanics School of Mechanical EngineeringTianjin UniversityTianjin300350China Insttute of Process quipment College of Energy EngineeringZhejiang UniversityHangzhou30027China

Based on a semi-resolved CFD-DEM coupling method,this study proposed a method that uses the minimum distance between the fluid grid and the particle boundary as a reference value to determine the degree of influence of the target fluid grid on the particle's drag force.A fluidized bed of rod-like particles was chosen as a typical case to investigate the effect of different fluid grid scales on various fluidized bed characteristic *** calculation performance of the semi-resolved and unre-solved CFD-DEM coupling algorithm on key fluidized bed characteristic parameters such as average pressure drop,particle frequency distribution with bed height,and particle orientation distribution were *** was found that the semi-resolved CFD-DEM coupling algorithm gradually obtained results with higher consistency with decreasing fluid grid scale for key parameters such as particle frequency distribution with bed height,particle orientation distribution,and time-history mixing index,exhibiting a phenomenon similar to grid independence in fluid *** comparing with experimental results,it was verified that the semi-resolved CFD-DEM coupling algorithm can be applied to simulate multi-granular gas-solid systems with fluid grid scales equivalent to particle *** algorithm solves the limitation of fluid grid scale in the unresolved CFD-DEM coupling framework and improves the grid adaptability of the CFD-DEM coupling simulation algorithm.

关键词： CFD-DEM Semi-resolved method Fluid-solid flow Non-spherical particle Fluidized bed

The Minimum Centroid Branch Spanning Tree Problem

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Journal of the Operations Research Society of China 2024年第2期12卷 528-539页

作者： Hao Lin Cheng he School of Science Henan University of TechnologyZhengzhou450001HenanChina

For a spanning tree T of graph G,the centroid of T is a vertex v for which the largest component of T-v has as few vertices as *** number of vertices of this component is called the centroid branch weight of *** minimum centroid branch spanning tree problem is to find a spanning tree T of G such that the centroid branch weight is *** application to design of communication networks,the loads of all branches leading from the switch center should be as balanced as *** this paper,we prove that the problem is strongly NP-hard even for bipartite ***,the problem is shown to be polynomially solvable for split graphs,and exact formulae for special graph familis,say Kn_(1),n_(2),...,n_(k)and P_(m)×P_(n),are presented.

关键词： Spanning tree optimization Centroid branch-NP-hardness Polynomial-time algorithm

Multi-Scale-Matching neural networks for thin plate bending problem

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 11-15页

作者： Lei Zhang Guowei he The State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Physics-informed neural networks are a useful machine learning method for solving differential equations,but encounter challenges in effectively learning thin boundary layers within singular perturbation *** resolve this issue,multi-scale-matching neural networks are proposed to solve the singular perturbation *** by matched asymptotic expansions,the solution is decomposed into inner solutions for small scales and outer solutions for large scales,corresponding to boundary layers and outer regions,***,to conform neural networks,we introduce exponential stretched variables in the boundary layers to avoid semiinfinite region *** results for the thin plate problem validate the proposed method.

关键词： Singular perturbation Physics-informed neural networks Boundary layer Machine learning

On n-universal quadratic forms over dyadic local fields

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Science China Mathematics 2024年第7期67卷 1481-1506页

作者： Zilong he Yong Hu School of Computer Science and Technology Dongguan University of TechnologyDongguan523808China Department of Mathematics Southern University of Science and TechnologyShenzhen518055China

Let n≥2 be an integer. We give necessary and sufficient conditions for an integral quadratic form over dyadic local fields to be n-universal by using invariants from Beli's theory of bases of norm ***, we provide a minimal set for testing n-universal quadratic forms over dyadic local fields, as an analogue of Bhargava and Hanke's 290-theorem(or Conway and Schneeberger's 15-theorem) on universal quadratic forms with integer coefficients.

关键词： integral quadratic forms n-universal quadratic forms dyadic fields 290-theorem

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Regulation of insect behavior by non-coding RNAs

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Science China(Life Sciences) 2024年第6期67卷 1106-1118页

作者： Jing he Le Kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institutes of Life Sciences Chinese Academy of SciencesBeijing 100101China College of Life Science Hebei UniversityBaoding 071002China

The adaptation of insects to environments relies on a sophisticated set of behaviors controlled by molecular and physiological *** the past several decades,accumulating studies have unveiled the roles of non-coding RNAs(nc RNAs)in regulating insect *** RNAs assume particularly pivotal roles in the behavioral plasticity of insects by rapidly responding to environmental *** RNAs also contribute to the maintenance of homeostasis of insects by fine-tuning the expression of target ***,a comprehensive review of nc RNAs'roles in regulating insect behaviors has yet to be ***,we present the recent progress in our understanding of how nc RNAs regulate various insect behaviors,including flight and movement,social behavior,reproduction,learning and memory,and *** refine the intricate mechanisms by which nc RNAs modulate the function of neural,motor,reproductive,and other physiological systems,as well as gene expression in insects like fruit flies,social insects,locusts,and ***,we discuss potential avenues for future studies in nc RNA-mediated insect behaviors.

关键词： ncRNAs insect behavior plasticity fine-tuning environmental adaptation

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Effect of SARS-CoV-2 infection in early pregnancy on placental development

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Science China(Life Sciences) 2024年第3期67卷 622-625页

作者： Shanru Yi Liping Wang Mengting Wang Wei Hong Ben Xu Xiaoying he Mengtian Yang Zhiping Wu Beiying Wang Guang Yang Shijun Shen Xinyu Cui Ruixue Wang Kai Wang Hong Wang Xiaocui Li Shaorong Gao Cizhong Jiang jiayu Chen Clinical and Translation Research Center of Shanghai First Maternity and Infant Hospital Shanghai Key Laboratory of Signaling and Disease ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of the Ministry of Education Orthopaedic Department of Tongji HospitalTongji UniversityShanghai 200065China Frontier Science Center for Stem cell Research Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Maternal Fetal Medicine Shanghai First Maternity and Infant HospitalSchool of MedicineTongji UniversityShanghai 201204China

Dear Editor,Since the COVID-19 pandemic, the potential risks associated with maternal SARS-CoV-2 infection and its effect on fetal development have been a subject of considerable public concern. Previous studies have ... 详细信息

关键词： pregnancy fetal Effect

Low profile cavity-embedded ultra-wideband UHF array antenna with end-fire beams

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Journal of Electronic Science and Technology 2024年第2期22卷 24-35页

作者： Huan he Wen-Song Wang Southwest China Institute of Electronic Technology Chengdu610036China School of Electrical and Electronic Engineering Department Nanyang Technological UniversitySingapore639798Singapore

A low-profile,vertically polarized,ultra-wideband array antenna with end-fire beams operating in an ultra-high frequency(UHF)band is developed in this *** array antenna consists of 1×16 log-periodic top-hat loaded monopole antenna arrays and is feasible to embed into a shallow cavity to further reduce the array *** is introduced in the proposed antenna element to reduce profile height and the rectangular top hats are carefully designed to minimize the transverse *** results show that when the antenna array operates in a frequency range of 300 MHz-900 MHz,the end-fire radiation pattern achieves±45°scanning range in the horizontal *** prototypes of the proposed end-fire antenna element and a uniformly spaced linear array(1×2)are fabricated and *** end-fire antenna array should be suitable for airborne applications where low-profile and conformal scanning phased antenna arrays with end-fire radiations are *** design is attractive for airborne platform applications that are used to search,discover,identify,and scout the aerial target with vertically polarized beams.

关键词： End-fire radiation Low-profile Vertical polarization Log-periodic array