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Full-Scale Isogeometric Topology Optimization of Cellular Structures Based on Kirchhoff-Love Shells

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2479-2505页

作者： Mingzhe Huang Mi Xiao Liang gao Mian zhou Wei sha Jinhao Zhang State Key Lab of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China

Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight *** this paper,a full-scale isogeometric topology optimization(ITO)method based on Kirchhoff-Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is *** method utilizes high-order continuous nonuniform rational B-splines(NURBS)as basis functions for Kirchhoff-Love shell *** geometric and analysis models of thin shells are unified by isogeometric analysis(IgA)to avoid geometric approximation error and improve computational *** topological configurations of thin-shell structures are described by constructing the effective density field on the *** volume constraints are imposed in the proximity of each control point to obtain bone-like cellular *** facilitate numerical implementation,the p-norm function is used to aggregate local volume constraints into an equivalent global *** numerical examples are provided to demonstrate the effectiveness of the proposed *** simulation and comparative analysis,the results indicate that the cellular thin-shell structures optimized by the proposed method exhibit great load-carrying behavior and high damage robustness.

关键词： Cellular thin-shell structures isogeometric analysis full-scale topology optimization Kirchhoff–Love shells

Towards adaptive graph neural networks via solving prior-data conflicts

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 369-383页

作者： Xugang wu Huijun wu Ruibo WANg Xu zhou Kai LU College of Computer National University of Defense TechnologyChangsha 410073China

graph neural networks(gNNs)have achieved remarkable performance in a variety of graph-related *** evidence in the gNN community shows that such good performance can be attributed to the homophily prior;i.e.,connected nodes tend to have similar features and ***,in heterophilic settings where the features of connected nodes may vary significantly,gNN models exhibit notable performance *** this work,we formulate this problem as prior-data confict and propose a model called the mixture-prior graph neural network(MPgNN).First,to address the mismatch of homophily prior on heterophilic graphs,we introduce the non-informative prior,which makes no assumptions about the relationship between connected nodes and learns such relationship from the ***,to avoid performance degradation on homophilic graphs,we implement a soft switch to balance the effects of homophily prior and non-informative prior by learnable *** evaluate the performance of MPgNN on both synthetic and real-world *** show that MPgNN can effectively capture the relationship between connected nodes,while the soft switch helps select a suitable prior according to the graph *** these two designs,MPgNN outperforms state-of-the-art methods on heterophilic graphs without sacrificing performance on homophilic graphs.

关键词： graph neural networks Heterophily Prior-data conflict

Development and Catalytic Cracking Performance of Ultrastable Y Zeolite Rich in Secondary Pores

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 13-21页

作者： Li Jiaxing Wang Shengji sha Hao Wang Juan zhou Lingping Wang Lixia SINOPEC Research Institute of Petroleum Processing Co. LtdBeijing 100083China Catalyst Co. Ltd.Qilu BranchSINOPECZibo 255336China

A novel ultra-stable zeolite, NSZ, rich in secondary pores was developed through the combination of gas-phase andmild hydrothermal methods. This zeolite was successfully tested in an industrial setting for the first time in the world. The porestructure characteristics of the NSZ zeolite prepared for industrial use were analyzed and characterized using BET. The resultsindicate a significant increase in the secondary pore volume of NSZ zeolite compared to the existing ultra-stable zeolite HSZ-5, which is produced through a conventional gas-phase method. The average secondary pore volume to total pore volume ratioin NSZ zeolite was found to be 58.96% higher. The catalytic cracking performance of NSZ zeolite was evaluated. The resultsshowed that the NSC-LTA catalyst, with NSZ as the active component, outperformed the HSC-LTA catalyst with HSZ-5 zeolitein terms of obtaining more high-value products (gasoline and liquefied petroleum gas) during the hydrogenated light cycle oilprocessing. Additionally, the NSC-LTA catalyst showed a significant improvement in coke selectivity.

关键词： gas-phase ultra-stable zeolite catalyst catalytic cracking

Audio Mixing Inversion via Embodied Self-supervised Learning

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Machine Intelligence Research 2024年第1期21卷 55-62页

作者： Haotian zhou Feng Yu Xihong wu Department of AI Music and Music Information Technology Central Conservatory of MusicBeijing 100031China Laboratory of Music Artificial Intelligence Laboratory of Philosophy and Social SciencesMinistry of EducationBeijing 100031China School of Intelligence Science and Technology Peking UniversityBeijing 100871China

Audio mixing is a crucial part of music *** analyzing or recreating audio mixing,it is of great importance to conduct research on estimating mixing parameters used to create mixdowns from music recordings,i.e.,audio mixing ***,approaches of audio mixing inversion are rarely explored.A method of estimating mixing parameters from raw tracks and a stereo mixdown via embodied self-supervised learning is *** this work,several commonly used audio effects including gain,pan,equalization,reverb,and compression,are taken into *** method is able to learn an inference neural network that takes a stereo mixdown and the raw audio sources as input and estimate mixing parameters used to create the mixdown by iteratively sampling and *** the sampling step,the inference network predicts a set of mixing parameters,which is sampled and fed to an audio-processing framework to generate audio data for the training *** the training step,the same network used in the sampling step is optimized with the sampled data generated from the sampling *** method is able to explicitly model the mixing process in an interpretable way instead of using a black-box neural network model.A set of objective measures are used for *** experimental results show that this method has better performance than current state-of-the-art methods.

关键词： Audio mixing inversion intelligent audio mixing self-supervised learning audio signal processing deep learning

Quantitative effect of kerogen type on the hydrocarbon generation potential of Paleogene lacustrine source rocks,Liaohe Western Depression,China

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Petroleum Science 2024年第1期21卷 14-30页

作者： sha-sha Hui Xiong-Qi Pang Fu-Jie Jiang Chen-Xi Wang Shu-Xing Mei Tao Hu Hong Pang Min Li Xiao-Long zhou Kan-Yuan Shi State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of geosciences China University of Petroleum(Beijing)Beijing102249China Exploration and Development Research Institute PetroChina Liaohe Oilfield CompanyPanjin 124010LiaoningChina

Kerogen types exert a decisive effect on the onset and capacity of hydrocarbon generation of source *** source rocks in the Liaohe Western Depression are characterized by thick deposition,high total organic carbon(TOC)content,various kerogen types,and a wide range of thermal ***,their hydrocarbon generation potential and resource estimation can be *** this study,geochemical tests,numerical analysis,hydrocarbon generation kinetics,and basin modeling were integrated to investigate the differential effects of kerogen types on the hydrocarbon generation potential of lacustrine source *** hydrocarbon generation and expulsion(HgE)models of different kerogen types were established quantitatively upon abundant Rock-Eval/TOC/vitrinite reflectance(R_(o))*** sets of good-excellent source rocks deposited in the fourth(Es4),third(Es3),and first(Es1)members of Paleogene shahejie Formation,are predominantly types I-II_(1),II_(1)-II_(2),and II-III,*** activation energy of types I-II_(2)kerogen is concentrated(180-230 kcal/mol),whereas that of type III kerogen is widely distributed(150-280 kcal/mol).The original hydrocarbon generation potentials of types I,II_(1),II_(2),and III kerogens are 790,510,270,and 85 mg/g TOC,*** Ro values of the hydrocarbon generation threshold for type I-III source rocks gradually increase from 0.42%to 0.74%,and Ro values of the hydrocarbon expulsion threshold increase from 0.49%to 0.87%.Types I and II_(1)source rocks are characterized by earlier hydrocarbon generation,more rapid hydrocarbon expulsion,and narrower hydrocarbon generation windows than types II_(2)and III source *** kerogen types also affect the HgE history and resource *** types(conventional,tight,and shale oil/gas)and three levels(realistic,expected,and prospective)of hydrocarbon resources of different members in the Liaohe Western Depression are *** suggest that t

关键词： Kerogen type Hydrocarbon generation potential Lacustrine source rocks Liaohe western depression

An interlaminar damage shell model for typical composite structures

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Chinese Journal of Aeronautics 2024年第1期37卷 118-137页

作者： Jie zhou Zhen wu Zhengliang LIU Xiaohui REN School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China National Key Laboratory of Strength and Structural Integrity Xi’an 710065China School of Mechanical Engineering Xi’an Aeronautical UniversityXi’an 710065China

Using the plate/shell elements in commercial software,accurate analysis of interlaminar initial damage in typical composite structures is still a challenging *** propose an accurate and efficient model for analysis of interlaminar initial damage,the following work is carried out:(A)A higher-order theory is firstly proposed by introducing the local Legendre polynomials,and then a novel shell element containing initial damage prediction is developed,which can directly predict transverse shear stresses without any postprocessing *** variables at each node are independent of number of layers,so the proposed model is more efficient than the 3D-FEM.(B)Compression experiment is carried out to verify the capability of the proposed *** results obtained from the proposed model are in good agreement with experimental data.(C)Several examples have been analyzed to further assess the capability of the proposed model by comparing to the 3D-FEM ***,accuracy and efficiency have been evaluated in different damage criterion by comparing with the selected *** numerical results show that the proposed model can well predict the initial interlaminar damage as well as other ***,the model is implemented with UEL subroutine,so that the present approach can be readily utilized to analyze the initial damage in typical composite structures.

关键词： Compression experiment Finite element method Initial damage Interlaminar stress Plate/shell element

Simulation of roof snow loads based on a multi-layer snowmelt model:Impact of building heat transfer

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Building Simulation 2024年第6期17卷 907-932页

作者： Xuanyi zhou Heng Chen Yue wu Tiange Zhang State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai200092China

To investigate the impact of building heat transfer on roof snow loads,roof snow loads and snow load thermal coefficients from 61 Chinese sites over a period of 50 years are simulated based on basic meteorological data such as temperature,humidity,wind speed,and precipitation,and a multi-layer snowmelt model considering the building heat ***,the accuracy of the multi-layer snowmelt model is validated using the data of observed ground snow load and roof snow melting *** relationship between meteorological conditions,snow cover characteristics,and thermal coefficients of snow loads in three representative sites is then ***,the characteristics of thermal coefficients in each zone are analyzed by combining them with the statistical results of meteorological data from 1960 to 2010,and the equations of thermal coefficients in different zones on indoor temperatures and roof heat transfer coefficients are fitted ***,the equations in this paper are compared with the thermal coefficients in the main snow load *** results indicate that the snowmelt model using basic meteorological data can effectively provide samples of roof snow *** the cold zone where the snow cover lasts for a long time and does not melt easily,the thermal coefficients of the snow loads on the heating buildings are lower than those in the warm zone due to the long-term influence of the heat from inside the *** coefficients are negatively correlated with indoor temperatures and roof heat transfer *** the indoor temperature is too low or the roof insulation is good,the roof snow load may exceed the ground snow *** thermal coefficients for heated buildings in the main snow load codes are more conservative than those calculated in this paper,and the thermal coefficients for buildings with lower indoor temperatures tend to be smaller.

关键词： snowmelt model roof snow load building heat transfer thermal coefficient load code

Research on modeling and self-excited vibration mechanism in magnetic levitation-collision interface coupling system

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 873-890页

作者： Jinghu TANg Chaofeng LI Jin zhou Zhiwei wu School of Mechanical Engineering&Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems of Ministry of Education of China Northeastern UniversityShenyang 110819China School of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The modeling and self-excited vibration mechanism in the magnetic levitation-collision interface coupling system are *** effects of the control and interface parameters on the system's stability are *** frequency range of self-excited vibrations is investigated from the energy point of *** phenomenon of self-excited vibrations is elaborated with the phase *** corresponding control strategies are briefly analyzed with respect to the vibration *** results show that when the levitation objects collide with the mechanical interface,the system's vibration frequency becomes larger with the decrease in the collision gap;when the vibration frequency exceeds the critical frequency,the electromagnetic system continues to provide energy to the system,and the collision interface continuously dissipates energy so that the system enters the self-excited vibration state.

关键词： magnetic levitation coupling system self-excited vibration mechanical interface vibration frequency

graph neural network-based scheduling for multi-UAV-enabled communications in D2D networks

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Digital Communications and Networks 2024年第1期10卷 45-52页

作者： Pei Li Lingyi Wang Wei wu Fuhui zhou Baoyun Wang Qihui wu Nanjing University of Posts and Telecommunications Nanjing210023China Nanjing University of Aeronautics and Astronautics Nanjing210016China

In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)*** objective is to maximize the total transmission rate of Downlink Users(DUs).Meanwhile,the Quality of Service(QoS)of all D2D users must be *** comprehensively considered the interference among D2D communications and downlink *** original problem is strongly non-convex,which requires high computational complexity for traditional optimization *** to make matters worse,the results are not necessarily globally *** this paper,we propose a novel graph Neural Networks(gNN)based approach that can map the considered system into a specific graph structure and achieve the optimal solution in a low complexity ***,we first construct a gNN-based model for the proposed network,in which the transmission links and interference links are formulated as vertexes and edges,***,by taking the channel state information and the coordinates of ground users as the inputs,as well as the location of UAVs and the transmission power of all transmitters as outputs,we obtain the mapping from inputs to outputs through training the parameters of *** results verified that the way to maximize the total transmission rate of DUs can be extracted effectively via the training on ***,it also shows that the performance of proposed gNN-based method is better than that of traditional means.

关键词： Unmanned aerial vehicle D2 Dcommunication graph neural network Power control Position planning