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Computers, Materials & Continua 2024年第9期80卷 3555-3572页

作者： Shih-lin lin Bo-chen lin Graduate Institute of Vehicle Engineering National Changhua University of EducationChanghua50007TaiwanChina

This paper explores the application of Model Predictive Control(MPC)to enhance safety and efficiency in autonomous vehicle(AV)navigation through optimized path *** evolution of AV technology has progressed rapidly,moving from basic driver-assistance systems(Level 1)to fully autonomous capabilities(Level 5).Central to this advancement are two key functionalities:Lane-Change Maneuvers(LCM)and Adaptive Cruise Control(ACC).In this study,a detailed simulation environment is created to replicate the road network between Nantun andWuri on National Freeway No.1 in *** MPC controller is deployed to optimize vehicle trajectories,ensuring safe and efficient *** onboard sensors,including vehicle cameras and millimeterwave radar,are used to detect and respond to dynamic changes in the surrounding environment,enabling real-time decision-making for LCM and *** simulation resultshighlight the superiority of the MPC-based approach in maintaining safe distances,executing controlled lane changes,and optimizing fuel ***,the MPC controller effectively manages collision avoidance,reduces travel time,and contributes to smoother traffic flow compared to traditional path planning *** findings underscore the potential of MPC to enhance the reliability and safety of autonomous driving in complex traffic *** research will focus on validating these results through real-world testing,addressing computational challenges for real-time implementation,and exploring the adaptability of MPC under various environmental *** study provides a significant step towards achieving safer and more efficient autonomous vehicle navigation,paving the way for broader adoption of MPC in AV systems.

关键词： Autonomous driving model predictive control(MPC) lane change maneuver(LCM) adaptive cruise control(ACC)

Multiscale Characteristics and Connection Mechanisms of Attraction Networks:A Trajectory Data Mining Approach Leveraging Geotagged Data

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Chinese Geographical Science 2024年第3期34卷 533-547页

作者： jiang Hongqiang WEI Ye MEI lin WANG Zhaobo School of Resource and Environment Engineering Ludong UniversityYantai 264025China School of Geographical Sciences Northeast Normal UniversityChangchun 130024China Changchun University of Finance and Economics Changchun 130122China Jilin Jizhi City Architectural Design Co. LTDChangchun 130012China

Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and connection mechanisms of attraction networks is important for understanding the linkages between attractions and even the future destination *** paper uses geotagging data to compare the links between attractions in Beijing,China during four different periods:the pre-Olympic period(2004–2007),the Olympic Games and subsequent‘heat period’(2008–2013),the post-Olympic period(2014–2019),and the COVID-19(Corona Virus Disease 2019)pandemic period(2020–2021).The aim is to better understand the evolution and patterns of attraction networks at different scales in Beijing and to provide insights for tourism planning in the *** results show that the macro,meso-,and microscales network characteristics of attraction networks have inherent logical relationships that can explain the commonalities and differences in the development process of tourism *** macroscale attraction network degree Matthew effect is significant in the four different periods and exhibits a morphological monocentric structure,suggesting that new entrants are more likely to be associated with attractions that already have high *** mesoscale links attractions according to the common purpose of tourists,and the results of the community segmentation of the attraction networks in the four different periods suggest that the functional polycentric structure describes their clustering effect,and the weak links between clusters result from attractions bound by incomplete information and distance,and the functional polycentric structure with a generally more efficient network of *** pattern structure at the microscale reveals the topological transformation relationship of the regional collaboration pattern,and the attraction network structure in the four diff

关键词： attraction network travel mobility polycentric structure network motif connectivity mechanism destination management organization(DMO) destination planning Beijing,China

Drug-Target Interactions Prediction Based on Signed Heterogeneous Graph Neural Networks

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Chinese Journal of Electronics 2024年第1期33卷 231-244页

作者： Ming chen Yajian jiang Xiujuan LEI Yi PAN Chunyan JI Wei jiang College of Information Science and Engineering Hunan Normal University School of Computer Science Shaanxi Normal University Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences Computer Science Department BNU-HKBU United International College

Drug-target interactions(DTIs) prediction plays an important role in the process of drug *** computational methods treat it as a binary prediction problem, determining whether there are connections between drugs and targets while ignoring relational types information. Considering the positive or negative effects of DTIs will facilitate the study on comprehensive mechanisms of multiple drugs on a common target, in this work, we model DTIs on signed heterogeneous networks, through categorizing interaction patterns of DTIs and additionally extracting interactions within drug pairs and target protein pairs. We propose signed heterogeneous graph neural networks(SHGNNs), further put forward an end-to-end framework for signed DTIs prediction, called SHGNN-DTI,which not only adapts to signed bipartite networks, but also could naturally incorporate auxiliary information from drug-drug interactions(DDIs) and protein-protein interactions(PPIs). For the framework, we solve the message passing and aggregation problem on signed DTI networks, and consider different training modes on the whole networks consisting of DTIs, DDIs and PPIs. Experiments are conducted on two datasets extracted from Drug Bank and related databases, under different settings of initial inputs, embedding dimensions and training modes. The prediction results show excellent performance in terms of metric indicators, and the feasibility is further verified by the case study with two drugs on breast cancer.

关键词： Drugs Training Proteins Measurement Message passing Prediction methods Graph neural networks

Sustainable development of unconventional resources: Analysis of the transient linear flow oriented straight-line analysis technique

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Energy Reviews 2024年第1期3卷 49-75页

作者： Dan Xue Liangliang jiang Zixiang Wei Maojie Chai jiang Liu Peng Deng Fuhe lin Jian Li Jiansheng Zhang Zhangxing chen Department of Chemical and Petroleum Engineering University of CalgaryCalgaryAlbertaCanada Guangdong University of Petrochemical and Technology MaomingChina School of Mathematics and Data Science Shaanxi University of Science and TechnologyXi'anChina Department of Energy and Power Engineering Tsinghua UniversityBeijingChina Eastern Institute for Advanced Study NingboChina China University of Petroleum(Beijing) BeijingChina

On the backdrop of dwindling conventional reserves,unconventional reservoirs have emerged as a pivotal chapter in resource *** their challenges,such as low permeability,complex fluid storage,and flow mechanisms,hydraulic fracturing technology has underpinned the development of unconventional ***,this has brought about a shift in the sequence of flow regimes,e.g.,the transient radial flow regime has been largely shortened by the lengthy transient linear flow regime due to the low permeability of unconventional ***,straight-line analysis(SLA),the simplest technique in rate transient analysis(RTA),is a fundamental and potent tool for swiftly extracting reservoir and hydraulic fracture information,estimating oil and gas reserves,and furnishing crucial initial data for subsequent historical matching ***,there is currently a dearth of review papers pertaining to a necessary guide of applying SLA in various transient linear flow(TLF)regimes and different unconventional ***,this paper commences by elucidating the classification of TLF regimes,commonly used methods for recognizing flow regimes,and the diverse SLA methods used for different TLF ***,it delves into a discussion of different modification techniques for variable rate/flowing pressure,gas phase,complex reservoir characteristics in unconventional reservoirs,and dynamic drainage area concepts ***,the application of SLA in specific domains,namely core analysis and the flowback period,is *** culminates by surveying the advancements through an integration of novel technologies to enhance estimation *** paper also highlights certain drawbacks of current SLA technology and proposes new research ***,this paper would serve as an indispensable resource,offering foundational knowledge for the application of SLA in TLF to promote the production of global unconventional resources in a c

关键词： Unconventional reservoirs Straight-line analysis(SLA) Transient linear flow(TLF) Oil/gas reserves Hydraulic fracture information

Core shift limitation in investment casting process of hollow turbine blade

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Chinese Journal of Aeronautics 2024年第8期37卷 513-526页

作者： Kang CUI lin JING Ruisong jiang Longnv YU Xiao GAO Automation and Software Engineering Shanxi UniversityTaiyuan 030006China Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologySchool of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China School of Mechanical Engineering Sichuan UniversityChengdu 610065China

The deviation in wall thickness caused by core shift during the investment casting process significantly impacts the strength and service life of hollow turbine *** address this issue,a core shift limitation method is developed in this ***,a shift model is established based on computational fluid dynamics and motion simulation to predict the movement of the ceramic core in investment casting ***,utilizing this model,an optimization method for fixturing layout inside the refractory ceramic shell is devised for the ceramic *** casting experiment demonstrates that by utilizing the optimized fixture layout,not only can core shift during the investment casting pouring process be effectively controlled,but also the maximum wall thickness error of the blade can be reduced by 42.02%.In addition,the core shift prediction is also validated,with a prediction error of less than 26.9%.

关键词： Hollow turbine blade Wall thickness Ceramic core Shift prediction Fixturing layout optimization

Numerical and experimental investigation into the evolution of the shock wave when a muzzle jet impacts a constrained moving body

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Defence Technology（防务技术） 2024年第3期33卷 317-326页

作者： Zijie Li Hao Wang Changshun chen Kun jiang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210016China

The gun-track launch system is a new special launch device that connects the track outside the *** it is constrained by the track,the characteristics of development of the muzzle jet differ from those of the traditional muzzle ***,it changes from freely developing to doing so in a constrained manner,where this results in an asymmetric direction of flow as well as spatio-temporal coupling-induced interference between various shock waves and the formation of *** this background,the authors of this article formulate and consider the development and characteristics of evolution of the muzzle jet as it impacts a constrained moving *** designed simulations to test the gun-track launch system,and established a numerical model based on the dynamic grid method to explore the development and characteristics of propagation of disturbances when the muzzle jet impacted a constrained moving *** also considered models without a constrained track for the sake of *** results showed that the muzzle jet assumed a circumferential asymmetric shape,and tended to develop in the area above the *** the test platform was close to the ground,the muzzle jet was subjected to reflections from it that enhanced the development and evolution of various forms of shock waves and vortices in the muzzle jet to exacerbate its rate of distortion and asymmetric *** in turn led to significant differences in the changes in pressure at symmetric points that would otherwise have been *** results of a comparative analysis showed that the constrained track could hinder the influence of reflections from the ground on the muzzle jet to some extent,and could reduce the velocity of the shock waves inducing the motion of the muzzle as well as the Mach number of the moving *** work here provides a theoretical basis and the requisite technical support for applications of the gun-track launch *** also sheds light on the

关键词： Shock wave/vortex interference Muzzle jet Constrained boundary Dynamic grid

CFD-DEM simulation of fluorination reaction in fluidized beds with local grid and time refinement method

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Particuology 2024年第1期84卷 145-157页

作者： Mofan Qiu lin jiang Rongzhen Liu Yaping Tang Malin Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyTsinghua UniversityBeijing100084China

The gas-solid reaction process with wide particle size distribution is extensively used in the chemical engineering field,especially the particle reacts with the gas gradually,such as fluorination reactions in fluidized *** the computational fluid dynamics-discrete element method(CFD-DEM)is used for the coupling simulation of multiphase and polydisperse particle reaction system,the grid size directly affects the accuracy of flow field information and simulation of chemical ***,particle calculation time step will directly affect the efficiency of coupling *** this work,a local grid and time step refinement method is proposed to simulate multiphase and polydisperse particle fluid-ization reaction *** this method,the refined DEM grids are automatically generated in the computational domain around the fine particles,and the detailed fluid phase information is obtained with the interpolation *** the two-phase coupling process,particles are divided into different groups based on physical properties,each group has its own independent time *** multistage conical-cylindrical spouted bed is proposed for the fluorination reaction process;the operating gas ve-locity range of the polydisperse particle system is extended by the new design while the particle size distribution changes with the gas-solid reaction *** is demonstrated that the local grid and time step refinement method can improve the accuracy and efficiency of the traditional CFD-DEM method in the reaction process simulation,which describes a polydisperse particle system with wide particle size *** at improving the simulation accuracy and efficiency,this paper will be helpful for simulating the particle reaction process in the gas-solid fluidized bed and beneficial for the development of the CFD-DEM method.

关键词： CFD-DEM Polydisperse particle Two-phase flow Fluidized bed

NSNO:Neumann Series Neural Operator for Solving Helmholtz Equations in Inhomogeneous Medium

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Journal of Systems Science & Complexity 2024年第2期37卷 413-440页

作者： chen Fukai LIU Ziyang lin Guochang chen Junqing SHI Zuoqiang Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China Yanqi Lake Beijing Institute of Mathematical Sciences and Applications Beijing 101408China

In this paper,the authors propose Neumann series neural operator(NSNO)to learn the solution operator of Helmholtz equation from inhomogeneity coefficients and source terms to *** equation is a crucial partial differential equation(PDE)with applications in various scientific and engineering ***,efficient solver of Helmholtz equation is still a big challenge especially in the case of high ***,deep learning has shown great potential in solving PDEs especially in learning solution *** by Neumann series in Helmholtz equation,the authors design a novel network architecture in which U-Net is embedded inside to capture the multiscale *** experiments show that the proposed NSNO significantly outperforms the state-of-the-art FNO with at least 60%lower relative L^(2)-error,especially in the large wavenumber case,and has 50%lower computational cost and less data ***,NSNO can be used as the surrogate model in inverse scattering *** tests show that NSNO is able to give comparable results with traditional finite difference forward solver while the computational cost is reduced tremendously.

关键词： Helmholtz equation inverse problem neumann series neural network solution operator

Quantifying quantum entanglement via machine learning models

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Communications in Theoretical Physics 2024年第7期76卷 52-56页

作者： Changchun Feng lin chen LMIB(Beihang University) Ministry of EducationBeijing 100191China School of Mathematical Sciences Beihang UniversityBeijing 100191China International Research Institute for Multidisciplinary Science Beihang UniversityBeijing 00191China

Quantifying entanglement measures for quantum states with unknown density matrices is a challenging *** learning offers a new perspective to address this *** training machine learning models using experimentally measurable data,we can predict the target entanglement *** this study,we compare various machine learning models and find that the linear regression and stack models perform better than *** investigate the model's impact on quantum states across different dimensions and find that higher-dimensional quantum states yield better ***,we investigate which measurable data has better predictive power for target entanglement *** correlation analysis and principal component analysis,we demonstrate that quantum moments exhibit a stronger correlation with coherent information among these data features.

关键词： quantum information entanglement predict machine learning coherence