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Particuology 2024年第3期86卷 137-148页

作者： Qiuhua Miao peng Huang Wenchang Zhu School of Mechanical Engineering Southeast UniversityNanjing211189China

Particle shape is an important factor affecting the fragmentation distribution of the ore *** investigate the influence of particle shape on the morphological fragmentation distribution characteristics,the crushable ore particles are defined as prolate,oblate ellipsoid and spherical particles,which have different aspect ratios(AR)and sphericity(S).Based on the drop weight experiment,the influence of the net drop height on the macroscopic mechanical behavior and crushing distribution characteristics of the single spherical and ellipsoidal particles is *** results show that different peak-shifting characteristics exist during particle *** fragmentation distribution peak shifts left when the increased impact energy is eventually only enough to break medium-sized ***,it shifts right when impact energy is increased enough to break largest-sized ***,regardless of whether the net drop height changes,the maximum continuous fragmentation degree presents"M"-shaped characteristic with the increased *** with the ellipsoid particles,the single spherical particle is more difficult to be broken by impact,with wider equivalent particle fragmentation *** the increase of particle sphericity,the maximum continuous fragmentation degree of a single ellipsoid particle has an overall trend of initial increase and subsequent *** when particle sphericity is 0.9

关键词： Ellipsoid particles Fragmentation distribution Drop weight experiment Numerical simulation

Resource Allocation to Minimize the Makespan with Multi-Resource Operations

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Journal of Systems Science & Complexity 2024年第5期37卷 2054-2070页

作者： WENG Wuyan CHU Chengbin WU peng School of Economics and Management Fuzhou University Univ Gustave Eiffel ESIEE Paris&COSYS-GRETTIA

This paper investigates a new resource-allocation problem involving multi-resource operations, where completing an operation requires simultaneous use of multiple(renewable) resources,probably of different types. The goal of the study is to provide a solution method that minimizes the makespan. The authors formulate the problem into a novel mixed-integer linear program(MILP)model. To efficiently solve practical-sized instances, an exact Benders decomposition algorithm is developed. This algorithm divides the original problem into a master problem of allocating resources and a subproblem of calculating the makespan, and both are linked via Benders cuts. The convergence is sped up by improving the mathematical model and embedding the variable neighborhood search algorithm. Compared with CPLEX, a commonly used MILP solver, the computational results demonstrate that the proposed algorithm provides tighter upper and lower bounds in most instances. In particular,compared with CPLEX, the proposed method can on average improve the upper and lower bounds by 4.76% and 4.39%, respectively, in solving practical-sized instances.

关键词： Benders decomposition multi-resources operations resource allocation

Cross-Dimension Attentive Feature Fusion Network for Unsupervised Time-Series Anomaly Detection

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3011-3027页

作者： Rui Wang Yao Zhou Guangchun Luo peng Chen Dezhong peng School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China School of Computer and Software Engineering Xihua UniversityChengdu610039China School of Computer Science Sichuan UniversityChengdu610065China National Innovation Center for UHD Video Technology Chengdu610095China

Time series anomaly detection is crucial in various industrial applications to identify unusual behaviors within the time series *** to the challenges associated with annotating anomaly events,time series reconstruction has become a prevalent approach for unsupervised anomaly ***,effectively learning representations and achieving accurate detection results remain challenging due to the intricate temporal patterns and dependencies in real-world time *** this paper,we propose a cross-dimension attentive feature fusion network for time series anomaly detection,referred to as ***,a series and feature mixing block is introduced to learn representations in 1D ***,a fast Fourier transform is employed to convert the time series into 2D space,providing the capability for 2D feature ***,a cross-dimension attentive feature fusion mechanism is designed that adaptively integrates features across different dimensions for anomaly *** results on real-world time series datasets demonstrate that CAFFN performs better than other competing methods in time series anomaly detection.

关键词： Time series anomaly detection unsupervised feature learning feature fusion

Enhanced potassium storage of carbon nanofibers as binderfree anodes enabled by coupling ultra-small amorphous Sb_(2)O_(3),graphene modification and sulfur doping

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Rare Metals 2024年第1期43卷 51-64页

作者： Zhao Huang Yu-Kang Lou Lin peng Yuan peng Meng-Meng Wang Ming Zhang College of Railway Transportation Hunan University of TechnologyZhuzhou 412007China College of Semiconductors(College of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan UniversityChangsha 410082China Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China

Considering the intrinsic advantages of natural copiousness and cost-effectiveness of potassium resource,potassium-ion batteries(KIBs) are booming as prospective alternatives to lithium-ion batteries(LIBs) in large-scale energy storage scenarios. Nevertheless, lacking desirable electrodes for reversibly hosting the bulky K+hinders the widespread application of KIBs, and it needs to be urgently solved. Hereon, the porous S-doped Sb_(2)O_(3)-graphene-carbon(SAGC) nanofibers are manufactured through an adjustable and facile approach, which involves electrospinning, in situ etching and sulfuration. The synthesized SAGC is featured by the ultra-small amorphous Sb_(2)O_(3) homogeneously wrapped inside the carbon matrix, as well as the co-incorporation of graphene and sulfur. Tentatively,the SAGC nanofiber sheets are applied as binder-free anodes for KIBs, exhibiting a prominent cycling life(256.72 m Ah·g^(-1) over 150 cycles at 100 m A·g^(-1)) and rate·g^(-1) over 100 cycles at 1 A·g^(-1)). The positive synergy among all the active components accounts for the distinguished performances of the SAGC. By reinforcing the tolerability to the swelling stress, producing the valid electrochemical active sites, and promoting the charge transferring for reversible K+uptake, the SAGC finally renders the excellent cyclability, capacity, and rate capability. Moreover, the extrinsic electrochemical pseudocapacitance characteristics induced by the porous carbon substrate elevate the K-storage capacity of the SAGC as well. It is hoped that the conclusions drawn may offer new insights into a direction for the high-performance binderfree KIB anodes.

关键词： S-doped Sb_(2)O_(3)-graphene-carbon Nanofibers Binder-free Anodes Potassium-ion batteries

Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains,China

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Journal of Forestry Research 2024年第3期35卷 197-208页

作者： Jinkuan Li Jianfeng peng Xiaoxu Wei Meng peng Xuan Li Yameng Liu Jiaxin Li College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Key Laboratory of Earth System Observation and Simulation of Henan Province Kaifeng 475004People’s Republic of China

Global warming will affect growth strategies and how trees will *** compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and treering chronologies developed on northern and western slopes from the Lubanling in the Funiu *** analyses showed that two chronologies were mainly limited by temperatures in the previous June–August and the combination of temperatures and moisture in the current May–*** difference of the climate response to slopes was small but not *** growth of the LBL01 site on the northern slope was affected by the combined maximum and minimum temperatures,while that of the LBL02 site was affected by maximum *** regards to moisture,radial growth of the trees on the north slope was influenced by the relative humidity in the current May–July,while on the western slope,it was affected by the relative humidity in the previous June–August,the current May–July and the precipitation in the current May–*** the change in climate,the effects of the main limiting factors on growth on different slopes were visible to a certain extent,but the differences in response of trees on different slopes gradually decreased,which might be caused by factors such as different slope directions and the change in diurnal temperature *** results may provide information for forest protection and ecological construction in this region,and a scientific reference for future climate reconstruction.

关键词： Tree ring width Lubanling Pinus armandii Franch Slope direction Climate response

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L vector spaces and L fields

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Science China Mathematics 2024年第10期67卷 2195-2216页

作者： Yinhe peng Liuzhen Wu Academy of Mathematics and Systems Science Chinese Academy of Sciences

We construct in ZFC(the Zermelo-Fraenkel system with choice) an L topological vector space—a topological vector space that is an L space—and an L field—a topological field that is an L space. This generalizes earli... 详细信息

关键词： minimal walk topological vector space topological field L space L vector space L field

Semi-derived Ringel-Hall algebras and Hall algebras of odd-periodic relative derived categories

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Science China Mathematics 2024年第8期67卷 1735-1760页

作者： Ji Lin Liangang peng Department of Mathematics and Statistics Fuyang Normal UniversityFuyang 236037China School of Mathematics Sichuan UniversityChengdu 610064China

Let t be a positive integer and A be a hereditary abelian category satisfying some finiteness *** define the semi-derived Ringel-Hall algebra of A from the category C_(Z/t)(A)of Z/t-graded complexes and obtain a natural basis of the semi-derived Ringel-Hall ***,we describe the semiderived Ringel-Hall algebra by the generators and defining *** particular,if t is an odd integer,we show an embedding of the derived Hall algebra of the odd-periodic relative derived category in the extended semi-derived Ringel-Hall algebra.

关键词： hereditary abelian categories the categories of Z/t-graded complexes semi-derived Ringel-Hall algebras derived Hall algebras

Multi-Level Parallel Network for Brain Tumor Segmentation

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 741-757页

作者： Juhong Tie Hui peng School of Software Engineering Chengdu University of Information TechnologyChengdu610225China

Accurate automatic segmentation of gliomas in various sub-regions,including peritumoral edema,necrotic core,and enhancing and non-enhancing tumor core from 3D multimodal MRI images,is challenging because of its highly heterogeneous appearance and *** convolution neural networks(CNNs)have recently improved glioma segmentation ***,extensive down-sampling such as pooling or stridden convolution in CNNs significantly decreases the initial image resolution,resulting in the loss of accurate spatial and object parts information,especially information on the small sub-region tumors,affecting segmentation ***,this paper proposes a novel multi-level parallel network comprising three different level parallel subnetworks to fully use low-level,mid-level,and high-level information and improve the performance of brain tumor *** also introduce the Combo loss function to address input class imbalance and false positives and negatives imbalance in deep *** proposed method is trained and validated on the BraTS 2020 training and validation *** the validation dataset,ourmethod achieved a mean Dice score of 0.907,0.830,and 0.787 for the whole tumor,tumor core,and enhancing tumor core,*** with state-of-the-art methods,the multi-level parallel network has achieved competitive results on the validation dataset.

关键词： Convolution neural network brain tumor segmentation parallel network

Brain Mechanisms Underlying Panic Attack and Panic Disorder

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Neuroscience Bulletin 2024年第6期40卷 795-814页

作者： Xuyan Guan peng Cao Tsinghua Institute of Multidisciplinary Biomedical Research Tsinghua UniversityBeijing102206China National Institute of Biological Sciences(NIBS) Beijing102206China

Panic disorder is a psychiatric disorder characterized by recurrent panic attacks,with a prevalence of~4%in the general population,causing heavy personal and socioeconomic *** similarities of animal defense responses to clinical panic attack symptoms in humans make it possible to translate neuroanatomical pathways identified in animal studies to panic disorder in ***,in this review we first present a basic overview of panic disorder in humans including the main subtypes,models commonly used to trigger panic attacks,related hypotheses,the neurotransmitter systems that may be involved,and the current clinical treatments to give the reader a comprehensive understanding of panic *** animal section introduces the models that trigger panic-like behavior in animals and the brain regions that may be involved,providing insights for future elucidation of the neural circuit mechanisms behind panic attacks.

关键词： Panic disorder Panic attack Defense responses Animal studies Humans

Long-time Asymptotics for the Reverse Space-time Nonlocal Hirota Equation with Decaying Initial Value Problem:without Solitons

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 708-727页

作者： Wei-qi peng Yong CHEN School of Mathematical Sciences East China Normal UniversityShanghai 200241China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this work,we mainly consider the Cauchy problem for the reverse space-time nonlocal Hirota equation with the initial data rapidly decaying in the solitonless *** from the Lax pair,we first construct the basis Riemann-Hilbert problem for the reverse space-time nonlocal Hirota ***,using the approach of Deift-Zhou nonlinear steepest descent,the explicit long-time asymptotics for the reverse space-time nonlocal Hirota is *** the reverse space-time nonlocal Hirota equation,since the symmetries of its scattering matrix are different with the local Hirota equation,the v(λ_(i))(i=0,1)would like to be imaginary,which results in theδ_(λi)^(0)contains an increasing t(±Imv(λ_(i)))/2,and then the asymptotic behavior for nonlocal Hirota equation becomes differently.

关键词： Riemann-Hilbert problem reverse space-time nonlocal Hirota equation long-time asymptotics nonlinear steepest descent method