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RE-SEGNN:recurrent semantic evidence-aware graph neural network for temporal knowledge graph forecasting

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Science China(Information Sciences) 2025年第2期68卷 103-119页

作者： Wenyu CAI Mengfan LI Xuanhua SHI Yuanxin fan Quntao ZHU hai JIN National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and Technology

Temporal knowledge graph(TKG) reasoning, has seen widespread use for modeling real-world events, particularly in extrapolation settings. Nevertheless, most previous studies are embedded models, which require both entity and relation embedding to make predictions, ignoring the semantic correlations among different entities and relations within the same timestamp. This can lead to random and nonsensical predictions when unseen entities or relations occur. Furthermore, many existing models exhibit limitations in handling highly correlated historical facts with extensive temporal depth. They often either overlook such facts or overly accentuate the relationships between recurring past occurrences and their current counterparts. Due to the dynamic nature of TKG, effectively capturing the evolving semantics between different timestamps can be *** address these shortcomings, we propose the recurrent semantic evidenceaware graph neural network(RE-SEGNN), a novel graph neural network that can learn the semantics of entities and relations simultaneously. For the former challenge, our model can predict a possible answer to missing quadruples based on semantics when facing unseen entities or relations. For the latter problem, based on an obvious established force, both the recency and frequency of semantic history tend to confer a higher reference value for the current. We use the Hawkes process to compute the semantic trend, which allows the semantics of recent facts to gain more attention than those of distant facts. Experimental results show that RE-SEGNN outperforms all SOTA models in entity prediction on 6 widely used datasets, and 5 datasets in relation prediction. Furthermore, the case study shows how our model can deal with unseen entities and relations.

关键词： knowledge graph reasoning temporal knowledge graph Hawkes process semantic evidence

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Influence of minor cerium addition on microstructure and fluidity of as-cast Al-Cu-Mn-Mg alloy

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Journal of Rare Earths 2025年第2期43卷 377-383页

作者： Yishan Wang Yu Bai Kaixi Jiang Wenxue fan Puxuan Wang hai Hao Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province) School of Materials Science and EngineeringDalian University of Technology Ningbo Research Institute of Dalian University of Technology

Al-Cu-Mn alloys are widely used to produce automobile components like cylinder heads and engine blocks because of their capability to retain excellent thermal and mechanical characteristics at high ***,the Al-Cu-Mn-based alloys demonstrate restricted fluidity,leading to casting defects such as shrinkage and incomplete *** research investigated the microstructure and fluidity of Al-4.7Cu-1.0Mn-0.5Mg（wt%） alloy with minor cerium（Ce） *** as-cast alloys predominantly comprise α-Al matrix,accompanied by the presence of Al2Cu,Al6Mn,and Al8Cu4Ce *** influence of adding Ce on the fluidity of the Al-4.7Cu-1.0Mn-0.5Mg alloy was investigated using a trispiral fluidity test mold in this *** findings suggest that the addition of Ce within the range of 0.1 wt% to 0.5 wt% in the Al-4.7Cu-1.0Mn-0.5Mg alloy results in an enhancement in ***,the alloy containing 0.4 wt% Ce exhibits a significant increase in fluidity distance,from 349.7 to 485.7 *** improvement can be attributed to the reduction in viscosity,the refinement of secondary dendrite arm spacing,and the modification of secondary phase ***,a higher concentration of Ce leads to a decrease in fluidity length,potentially due to the formation of Al8Cu4Ce.

关键词： Al-Cu-Mn-Mg alloy Ce addition Fluidity Microstructure Rare earths

Application of landscape ecology to the research on wetlands

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Journal of Forestry Research 2008年第2期19卷 164-170页

作者： WANG Ying-zi HONG Wei WU Cheng-zhen HE Dong-jin LIN Shu-wei fan hai-lan Key Laboratory for Forest Ecosystem Process and Management of Fujian Province Fuzhou 350002P.R.China Forestry college of Fujian Agriculture and Forestry University Fuzhou 350002P.R.China

This review describes the characteristics and hot spots of wetland research, including biodiversity protection of wetland, management and restoration of wetland, function and process of wetland, and the theories, methods and scales of landscape ecology. Moreover, some deficits of landscape ecology theory and method were discussed, and the application of landscape ecology to research on wetlands was reviewed specially, involving in the application of landscape structure principle, landscape pattern, and scale and hierarchy theory. In conclusion, landscape ecology plays an enlightening and guiding function on the comprehensive research of wetlands at multi-scales.

关键词： wetland landscape ecology landscape structure landscape pattern scale and hierarchy

Rapid detection of colored and colorless macroand micro-plastics in complex environment via near-infrared spectroscopy and machine learning

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Journal of Environmental Sciences 2025年第1期147卷 512-522页

作者： Hui-Huang Zou Pin-Jing He Wei Peng Dong-Ying lan Hao-Yang Xian fan Lü Hua Zhang Institute of Waste Treatment&Reclamation College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

To better understand the migration behavior of plastic fragments in the environment,development of rapid non-destructive methods for in-situ identification and characterization of plastic fragments is ***,most of the studies had focused only on colored plastic fragments,ignoring colorless plastic fragments and the effects of different environmental media(backgrounds),thus underestimating their *** address this issue,the present study used near-infrared spectroscopy to compare the identification of colored and colorless plastic fragments based on partial least squares-discriminant analysis(PLS-DA),extreme gradient boost,support vector machine and random forest *** effects of polymer color,type,thickness,and background on the plastic fragments classification were ***-DA presented the best and most stable outcome,with higher robustness and lower misclassification *** models frequently misinterpreted colorless plastic fragments and its background when the fragment thickness was less than 0.1mm.A two-stage modeling method,which first distinguishes the plastic types and then identifies colorless plastic fragments that had been misclassified as background,was *** method presented an accuracy higher than 99%in different *** summary,this study developed a novel method for rapid and synchronous identification of colored and colorless plastic fragments under complex environmental backgrounds.

关键词： Colorless microplastics Near-infrared hyperspectral imaging Plastic identification Partial least squares discriminant analysis Machine learning

Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 311-324页

作者： Qian Yin fan Wen Zhigang Tao hai Pu Tianci Deng Yaoyao Meng Qingbin Meng Hongwen Jing Bo Meng Jiangyu Wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China

The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious ***,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of *** mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically *** results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,***,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the ***σ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite ***ε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse *** increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.

关键词： cemented gangue backfill materials particle size distribution true triaxial compression test carbon nanotubes mechanical properties failure modes

Density-Functional Theory of Quantum Droplets

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Chinese Physics Letters 2025年第1期42卷 28-33页

作者： fan Zhang lan Yin Hefei National Laboratory Hefei 230088China School of Physics Peking UniversityBeijing 100871China

In quantum droplets,the mean-field energy is comparable to the Lee-Huang-Yang(LHY)*** the Bogoliubov theory,the LHY energy of a quantum droplet has an imaginary part,which has been neglected in most studies for practical *** far,most theoretical studies on quantum droplets have been based on the extended Gross-Pitaevskii(GP)equation,which includes the contribution of the LHY energy to the chemical *** this article,we present the density-functional theory of quantum *** our approach,the quantum fluctuations in quantum droplets,as described by an effective action,generate a real correlation energy that can be determined *** density-functional theory,we calculated the energy,quantum depletion fraction,and excitations of the *** results for the ground-state energy and quantum depletion fractions were consistent with the Monte Carlo *** also discuss the implications of our theory.

关键词： potential. theory. quantum

Tackling the microlensing wave effects of strong lensing gravitational waves with TAAH

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 253-254页

作者： Zuhui fan South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China

The rapid development of gravitational wave(GW) observations since their first detection in 2015 [1] has opened a completely new window for exploring the Universe. Consequently, astronomical research has entered the multimessenger era, allowing us to use different tracers to view the cosmos from various perspectives. Among others, the appealing application of gravitational wave events from compact binary mergers is that they can act as standard sirens to determine absolute cosmic distances entirely independent of standard candles. This approach is one of the most promising means to solve the current H0tension problem.

关键词： problem. app wave

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珍稀濒危植物桫椤种群生命过程及谱分析

应用生态学报 2008年第12期19卷 2577-2582页

作者：宋萍洪伟吴承祯封磊范海兰福建农林大学林学院福州350002 福建农林大学资源与环境学院福州350002

根据种群生命表和生存分析理论,以高度级为基础编制了桫椤种群特定时间生命表,绘制了生存函数曲线,分析了种群的生命过程.结果表明:桫椤种群结构为前期增长、后期稳定类型.生命期望在第4龄级最大,此阶段种群生存质量相对较高.种群存活... 详细信息

根据种群生命表和生存分析理论,以高度级为基础编制了桫椤种群特定时间生命表,绘制了生存函数曲线,分析了种群的生命过程.结果表明:桫椤种群结构为前期增长、后期稳定类型.生命期望在第4龄级最大,此阶段种群生存质量相对较高.种群存活曲线属于典型的Deevey-Ⅲ型.种群生命过程有3个死亡高峰期,分别是第2龄级向第3龄级、第10龄级向第11龄级和第12龄级向第13龄级生长阶段.种群存活率随龄级增加呈单调减少,相应的积累死亡率呈单调增加,变动幅度为前期大、后期小;死亡密度函数曲线呈现前期下降、后期平缓稳定的特点,凹点出现于第4龄级.谱分析结果显示,桫椤种群数量波动性是大周期内有小周期的多谐波迭加,各周期作用基本上随周期的缩短而减小,基波的影响最显著.

关键词：桫椤种群生命表存活曲线谱分析

Post-silking leaf senescence is delayed in low-N-tolerant maize cultivars under low N fertilization

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Crop Journal 2025年第1期13卷 246-256页

作者： Wei, Gui Wang, Xinglong Wu, Yawei Liu, fan lan, Tianqiong Liu, Qinlin Lyu, Chengcheng Kong, fanlei Yuan, Jichao College of Agronomy Sichuan Agricultural University Sichuan Chengdu 611130 China Key Laboratory of Crop Ecophysiology and Farming System in Southwest China Ministry of Agriculture Sichuan Chengdu 611130 China Crop Ecophysiology and Cultivation Key Laboratory of Sichuan Province Sichuan Chengdu 611130 China

A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatio-temporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them, as well as to reveal the differences in post-silking chlorophyll degradation between low-N-tolerant cultivars. The results showed that the order of leaf senescence after silking in maize was lower leaf > upper leaf > ear leaf, leaf tip > middle > base. Increasing N fertilizer down-regulated the expression of ZmCLH2 and ZmPPH in the leaves at 10–30 d after silking, reducing CLH and PPH activities, thereby delaying the leaf senescence. These effects were more prominent in low-N-sensitive cultivar Xianyu 508 (XY508) than in low-N-tolerant cultivar Zhenghong 311 (ZH311), especially in the lower leaves and leaf tip. Under low N condition, leaf yellowing and chlorophyll degradation occurred later and slower in ZH311 than in XY508. This resulted in a higher post-silking dry matter accumulation and grain yield in ZH311, which may be one of the important physiological bases of low nitrogen tolerant cultivars. Future research should focus on developing low-N-tolerant maize cultivars with slower leaf senescence near the ear after silking. © 2024

关键词： Chlorophyll degradation Low-N-tolerant maize variety Nitrogen fertilizer Spatio-temporal characteristics