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Predicting Traffic Flow Using Dynamic Spatial-Temporal Graph Convolution Networks

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Computers, Materials & Continua 2024年第3期78卷 4343-4361页

作者： Yunchang Liu Fei Wan Chengwu liang School of Computer and Data Science Henan University of Urban ConstructionPingdingshan467036China School of Electrical and Control Engineering Henan University of Urban ConstructionPingdingshan467036China

Traffic flow prediction plays a key role in the construction of intelligent transportation ***,due to its complex spatio-temporal dependence and its uncertainty,the research becomes very *** of the existing studies are based on graph neural networks that model traffic flow graphs and try to use fixed graph structure to deal with the relationship between ***,due to the time-varying spatial correlation of the traffic network,there is no fixed node relationship,and these methods cannot effectively integrate the temporal and spatial *** paper proposes a novel temporal-spatial dynamic graph convolutional network(TSADGCN).The dynamic time warping algorithm(DTW)is introduced to calculate the similarity of traffic flow sequence among network nodes in the time dimension,and the spatiotemporal graph of traffic flow is constructed to capture the spatiotemporal characteristics and dependencies of traffic *** combining graph attention network and time attention network,a spatiotemporal convolution block is constructed to capture spatiotemporal characteristics of traffic *** on open data sets PEMSD4 and PEMSD8 show that TSADGCN has higher prediction accuracy than well-known traffic flow prediction algorithms.

关键词： Intelligent transportation graph convolutional network traffic flow DTW algorithm attention mechanism

Observational appearances of hairy black holes in the framework of gravitational decoupling

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Communications in Theoretical Physics 2024年第8期76卷 103-117页

作者： Yizhi liang Xin Lyu Jun Tao Center for Theoretical Physics College of PhysicsSichuan UniversityChengdu 610065China

We investigate the observational appearance of static and spherically symmetric hairy black holes in the framework of gravitational decoupling with the weak energy condition(WEC). Two types of thin illumination conditions are studied: spherical accretion and disk accretion. As the hairy parameter increases, the size of the photon sphere and photon rings in both models decreases, and the overall luminosity attenuation becomes more pronounced. In spherical accretion, the luminosity of infalling accretion is significantly lower than that of stationary accretion. In disk accretion the luminosity of the black hole is contributed by direct emission, the lensing ring and the photon ring. Employing four types of astrophysical disk luminosity model,we investigate the appearance of halos and note that their luminosities do not superimpose when the source is on or beyond the innermost stable circular orbit.

关键词： hairy black hole shadow gravitational decoupling accretion disk

Effect of land use on soil nematode community composition and co-occurrence network relationship

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Journal of Integrative Agriculture 2024年第8期23卷 2807-2819页

作者： Xiaotong Liu Siwei liang Yijia Tian Xiao Wang Wenju liang Xiaoke Zhang Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China Tillage and Cultivation Research Institute Liaoning Academy of Agricultural SciencesShenyang 110161China University of Chinese Academy of Sciences Beijing 100049China Key Lab of Conservation Tillage and Ecological Agriculture in Liaoning Province Shenyang 110016China

Land use influences soil biota community composition and diversity,and then belowground ecosystem processes and *** characterize the effect of land use on soil biota,soil nematode communities in crop land,forest land and fallow land were investigated in six regions of northern *** richness,diversity,abundance and biomass of soil nematodes was the lowest in crop *** richness and diversity of soil nematodes were 28.8and 15.1%higher in fallow land than in crop land,*** significant differences in soil nematode indices were found between forest land and fallow land,but their network keystone genera composition was *** the keystone genera,50%of forest land genera were omnivores-predators and 36%of fallow land genera were *** proportion of fungivores in forest land was 20.8%lower than in fallow *** network complexity and the stability were lower in crop land than forest land and fallow *** pH,NH_(4)^(+)-N and NO_(3)^(–)-N were the major factors influencing the soil nematode community in crop land while soil organic carbon and moisture were the major factors in forest *** nematode communities in crop land influenced by artificial management practices were more dependent on the soil environment than communities in forest land and fallow *** use induced soil environment variation and altered network relationships by influencing trophic group proportions among keystone nematode genera.

关键词： soil nematode trophic groups community composition co-occurrence network land use

Pan Shuh:the founding figure of modern Chinese psychology

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Protein & Cell 2024年第4期15卷 235-238页

作者： Ligang Wang Tongqi Wei liang Wang Institute of Psychology Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Mental Health Institute of PsychologyBeijing 100101China Department of Psychology University of Chinese Academy of SciencesBeijing 101408China

Entering the lobby of the Institute of Psychology,Chinese Academy of Sciences,the first thing that catches the eye is the Pan Shuh *** the library,Pan Shuh’s six decades of life are displayed in the form of a life photo exhibition,representing 10 years of determination,10 years of wandering,10 years of exploration,10 years of following the path,10 years of self-improvement,and 10 years of *** six decades not only reflect the life journey of Pan Shuh,the pioneer of Chinese psychology but also serve as a microcosm of the historical development of modern Chinese psychology(Qicheng Jing,Xiaolan Fu,2011).

关键词： founding representing Shu

Cracking on a nickel-based superalloy fabricated by direct energy deposition

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China Foundry 2024年第4期21卷 311-318页

作者： Xue Zhang Ya-hang Mu liang Ma Jing-jing liang Yi-zhou Zhou Xiao-feng Sun Jin-guo Li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

Cracks have consistently been a significant challenge limiting the development of additive manufactured nickel-based *** is essential to investigate the location of cracks and their forming *** study extensively examines the impact of solidification process,microstructural evolution,and stress concentration on crack initiation during direct energy deposition(DED).The results emphasize that the crack formation is significantly related to large-angle grain boundaries,rapid cooling *** caused by large-angle grain boundaries and a fast-cooling rate predominantly appear near the edge of the deposited *** cracks are more likely to form near the top of the deposited sample,due to the presence ofγ/γ'*** secondary dendritic arm and the carbides in the interdendritic regions can obstruct liquid flow during the final stage of solidification,which results in the formation of solidification cracks and *** work paves the way to avoid cracks in nickel-based superalloys fabricated by DED,thereby enhancing the performance of superalloys.

关键词： location cracks direct energy deposition nickel-based superalloys

Hybrid stacking ensemble algorithm and simulated annealing optimization for stability evaluation of underground entry-type excavations

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Underground Space 2024年第4期17卷 25-44页

作者： Leilei Liu Guoyan Zhao Weizhang liang Zheng Jian School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The stability of underground entry-type excavations(UETEs)is of paramount importance for ensuring the safety of mining *** more engineering cases are accumulated,machine learning(ML)has demonstrated great potential for the stability evaluation of *** this study,a hybrid stacking ensemble method aggregating support vector machine(SVM),k-nearest neighbor(KNN),decision tree(DT),random forest(RF),multilayer perceptron neural network(MLPNN)and extreme gradient boosting(XGBoost)algorithms was proposed to assess the stability of ***,a total of 399 historical cases with two indicators were collected from seven ***,to pursue better evaluation performance,the hyperparameters of base learners(SVM,KNN,DT,RF,MLPNN and XGBoost)and meta learner(MLPNN)were tuned by combining a five-fold cross validation(CV)and simulated annealing(SA)*** on the optimal hyperparameters configuration,the stacking ensemble models were constructed using the training set(75%of the data).Finally,the performance of the proposed approach was evaluated by two global metrics(accuracy and Cohen’s Kappa)and three within-class metrics(macro average of the precision,recall and F1-score)on the test set(25%of the data).In addition,the evaluation results were compared with six base learners optimized by *** hybrid stacking ensemble algorithm achieved better comprehensive performance with the accuracy,Kappa coefficient,macro average of the precision,recall and F1-score were 0.92,0.851,0.885,0.88 and 0.883,*** rock mass rating(RMR)had the most important influence on evaluation ***,the critical span graph(CSG)was updated based on the proposed model,representing a significant improvement compared with the previous *** study can provide valuable guidance for stability analysis and risk management of ***,it is necessary to consider more indicators and collect more extensive and balanced dataset to validate the model in futur

关键词： Underground entry-type excavations(UETEs) Hybrid stacking ensemble Machine learning Simulated annealing Critical span graph Base and meta learners

Uniqueness on Difference Operators of Meromorphic Functions of Infinite Order

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Acta Mathematica Sinica,English Series 2024年第2期40卷 511-527页

作者： Hui LI Ming liang FANG Xiao YAO School of Science China University of Mining and TechnologyBeijing 100083P.R.China Institute of Mathematics Academy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100190P.R.China School of Sciences Hangzhou Dianzi UniversityHangzhou 310012P.R.China School of Mathematical sciences and LPMC Nankai UniversityTianjin 300071P.R.China

We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new *** is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ counting multiplicities with its difference operators Δcf(z) and Δ_(c)^(2)f(z), thenΔcf(z)≡Δ_(c)^(2)f(z).In particular,we give a difference analogue of a result of *** method has two distinct features:(ⅰ) It converts the relations between functions into the corresponding *** makes it possible to deal with the uniqueness problem by linear algebra and combinatorics.(ⅱ) It circumvents the obstacle of the difference logarithmic derivative lemma for meromorphic functions of infinite order,since this method does not depend on the growth of the ***,the idea in this paper can also be applied to the case for several variables.

关键词： Uniqueness meromorphic functions difference operators infinite order

Bending Analysis of Circular Piezoelectric Semiconductor Plates Incorporating Flexoelectricity

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Acta Mechanica Solida Sinica 2024年第4期37卷 613-621页

作者： liang Sun Zhengguang Xiao Chunli Zhang Weiqiu Chen Department of Engineering Mechanics Zhejiang UniversityHangzhou310027China Department of Basic Courses Naval University of EngineeringWuhan430033China Huanjiang Laboratory Zhuji311816China

Based on the three-dimensional(3D)basic equations of piezoelectric semiconductors(PSs),we establish a two-dimensional(2D)deformation-polarization-carrier coupling bending model for PS structures,taking flexoelectricity into *** analytical solutions to classical flexure of a clamped circular PS thin plate are *** the derived analytical model,we numerically investigate the distributions of electromechanical fields and the concentration of electrons in the circular PS thin plate under an upward concentrated *** effect of flexoelectricity on the multi-field coupling responses of the circular PS plate is *** obtained results provide theoretical guidance for the design of novel PS devices.

关键词： Piezoelectric semiconductor Plate model Flexoelectricity Multi-field coupling

Mathematical Modeling and a Multiswarm Collaborative Optimization Algorithm for Fuzzy Integrated Process Planning and Scheduling Problem

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Tsinghua Science and Technology 2024年第2期29卷 285-304页

作者： Qihao Liu Cuiyu Wang Xinyu Li liang Gao State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Considering both process planning and shop scheduling in manufacturing can fully utilize their complementarities,resulting in improved rationality of process routes and high-quality and efficient production. Hence,the study of Integrated Process Planning and Scheduling (IPPS) has become a hot topic in the current production field. However,when performing this integrated optimization,the uncertainty of processing time is a realistic key point that cannot be neglected. Thus,this paper investigates a Fuzzy IPPS (FIPPS) problem to minimize the maximum fuzzy completion time. Compared with the conventional IPPS problem,FIPPS considers the fuzzy process time in the uncertain production environment,which is more practical and realistic. However,it is difficult to solve the FIPPS problem due to the complicated fuzzy calculating rules. To solve this problem,this paper formulates a novel fuzzy mathematical model based on the process network graph and proposes a MultiSwarm Collaborative Optimization Algorithm (MSCOA) with an integrated encoding method to improve the optimization. Different swarms evolve in various directions and collaborate in a certain number of iterations. Moreover,the critical path searching method is introduced according to the triangular fuzzy number,allowing for the calculation of rules to enhance the local searching ability of MSCOA. The numerical experiments extended from the well-known Kim benchmark are conducted to test the performance of the proposed MSCOA. Compared with other competitive algorithms,the results obtained by MSCOA show significant advantages,thus proving its effectiveness in solving the FIPPS problem.

关键词： Integrated Process Planning and Scheduling(IPPS) fuzzy processing time fuzzy completion time MultiSwarm Collaborative Optimization Algorithm(MSCOA)