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Online learning-based model predictive trajectory control forconnected and autonomous vehicles: Modeling and physical tests

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Journal of Intelligent and Connected Vehicles

Journal of Intelligent and Connected Vehicles 2024年第2期7卷 86-96页

作者： Qianwen Li Peng Zhang Handong Yao Zhiwei Chen Xiaopeng Li school of Environmental CivilAgricultural and Mechanical EngineeringUniversity of GeorgiaAthens 30602USA Department of Civil and Environmental engineering University of Wisconsin–MadisonMadison 53706USA Department of Civil Architecturaland Environmental EngineeringDrexel UniversityPhiladelphia 19104USA

Motivated by the promising benefits of connected and autonomous vehicles (CAVs) in improving fuelefficiency, mitigating congestion, and enhancing safety, numerous theoretical models have been proposed to plan CAVmultiple-step trajectories (time–specific speed/location trajectories) to accomplish various operations. However, limitedefforts have been made to develop proper trajectory control techniques to regulate vehicle movements to follow multiplesteptrajectories and test the performance of theoretical trajectory planning models with field experiments. Without aneffective control method, the benefits of theoretical models for CAV trajectory planning can be difficult to harvest. This studyproposes an online learning-based model predictive vehicle trajectory control structure to follow time–specific speed andlocation profiles. Unlike single-step controllers that are dominantly used in the literature, a multiple-step model predictivecontroller is adopted to control the vehicle’s longitudinal movements for higher accuracy. The model predictive controlleroutput (speed) cannot be interpreted by vehicles. A reinforcement learning agent is used to convert the speed value to thevehicle’s direct control variable (i.e., throttle/brake). The reinforcement learning agent captures real-time changes in theoperating environment. This is valuable in saving parameter calibration resources and improving trajectory control accuracy.A line tracking controller keeps vehicles on track. The proposed control structure is tested using reduced-scale robot *** adaptivity of the proposed control structure is demonstrated by changing the vehicle load. Then, experiments on twofundamental CAV platoon operations (i.e., platooning and split) show the effectiveness of the proposed trajectory controlstructure in regulating robot movements to follow time-specific reference trajectories.

关键词： connected and autonomous vehicles(CAVs) reinforcement learning physical tests time-specific speed and location longitudinal and lateral control

Protective performance of shear stiffening gel-modified foam against ballistic impact:Experimental and numerical study

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Defence Technology（防务技术） 2024年第2期32卷 510-520页

作者： Huan Tu Haowei Yang Pengzhao Xu Zhe Yang Fan Tang Cheng Dong Yuchao Chen Lei Ren Wenjian Cao Chenguang Huang Yacong Guo Yanpeng Wei Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China school of Mechanical engineering Northwestern Polytechnical UniversityXi'an 710072China Xi'an Institute of electromechanical Information Technology Xi'an 710065China Science and Technology on Transient Impact Laboratory Beijing 102202China school of engineering Science University of Chinese Academy of SciencesBeijing 100049China

As one of the most widely used personal protective equipment(PPE),body armors play an important role in protecting the human body from the high-velocity impact of bullets or *** body torso and critical organs of the wear may suffer severe behind-armor blunt trauma(BABT)even though the impactor is stopped by the body armor.A type of novel composite material through incorporating shear stiffening gel(STG)into ethylene-vinyl acetate(EVA)foam is developed and used as buffer layers to reduce *** this paper,the protective performance of body armors composed of fabric bulletproof layers and a buffer layer made of foam material is investigated both experimentally and *** effectiveness of STG-modified EVA in damage relief is verified by ballistic *** parallel with the experimental study,numerical simulations are conducted by LS-DYNA®to investigate the dynamic response of each component and capture the key mechanical parameters,which are hardly obtained from field *** fully describe the material behavior under the transient impact,the selected constitutive models take the failure and strain rate effect into consideration.A good agreement between the experimental observations and numerical results is achieved to prove the validity of the modelling *** tests and simulations show that the impact-induced deformation on the human body is significantly reduced by using STG-modified EVA as the buffering *** improvement of protective performance is attributed to better dynamic properties and more outstanding energy absorption capability of the composite foam.

关键词： Ballistic behavior Composite foam Shear stiffening gel Finite element analysis Protective mechanism

Noise-Tolerant ZNN-Based Data-Driven Iterative Learning Control for Discrete Nonaffine Nonlinear MIMO Repetitive Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 344-361页

作者： Yunfeng Hu Chong Zhang Bo Wang Jing Zhao Xun Gong Jinwu Gao Hong Chen State Key Laboratory of Automotive Simulation and Control Jilin UniversityJilin UniversityChangchun 130025China College of Communication engineering Jilin UniversityJilin UniversityChangchun 130025China Department of electromechanical engineering University of MacaoMacao 999078China school of Artificial Intelligence Jilin UniversityChangchun 130012China IEEE College of Electronics and Information engineering Tongji UniversityShanghai 200092China

Aiming at the tracking problem of a class of discrete nonaffine nonlinear multi-input multi-output(MIMO) repetitive systems subjected to separable and nonseparable disturbances, a novel data-driven iterative learning control(ILC) scheme based on the zeroing neural networks(ZNNs) is proposed. First, the equivalent dynamic linearization data model is obtained by means of dynamic linearization technology, which exists theoretically in the iteration domain. Then, the iterative extended state observer(IESO) is developed to estimate the disturbance and the coupling between systems, and the decoupled dynamic linearization model is obtained for the purpose of controller synthesis. To solve the zero-seeking tracking problem with inherent tolerance of noise,an ILC based on noise-tolerant modified ZNN is proposed. The strict assumptions imposed on the initialization conditions of each iteration in the existing ILC methods can be absolutely removed with our method. In addition, theoretical analysis indicates that the modified ZNN can converge to the exact solution of the zero-seeking tracking problem. Finally, a generalized example and an application-oriented example are presented to verify the effectiveness and superiority of the proposed process.

关键词： Adaptive control control system synthesis data-driven iterative learning control neurocontroller nonlinear discrete time systems

Near-field radiative heat transfer between nanoporous GaN films

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Chinese Physics B 2024年第4期33卷 109-120页

作者：韩晓政张纪红刘皓佗吴小虎冷惠文 school of electromechanical and Automotive engineering Yantai UniversityYantai 264005China Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China Thermal Science Research Center Shandong Institute of Advanced TechnologyJinan 250100China

Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field *** research has highlighted that the introduction of nanopores into materials creates additional pathways for heat transfer,leading to a substantial enhancement of near-field radiative heat transfer(NFRHT).Being a direct bandgap semiconductor,GaN has high thermal conductivity and stable resistance at high temperatures,and holds significant potential for applications in optoelectronic ***,study of NFRHT between nanoporous GaN films is currently lacking,hence the physical mechanism for adding nanopores to GaN films remains to be discussed in the field of *** this work,we delve into the NFRHT of GaN nanoporous films in terms of gap distance,GaN film thickness and the vacuum filling *** results demonstrate a 27.2%increase in heat flux for a 10 nm gap when the nanoporous filling ratio is ***,the spectral heat flux exhibits redshift with increase in the vacuum filling *** be more precise,the peak of spectral heat flux moves fromω=1.31×10^(14)rad·s^(-1)toω=1.23×10^(14)rad·s^(-1)when the vacuum filling ratio changes from f=0.1 to f=0.5;this can be attributed to the excitation of surface phonon *** introduction of graphene into these configurations can highly enhance the NFRHT,and the spectral heat flux exhibits a blueshift with increase in the vacuum filling ratio,which can be explained by the excitation of surface plasmon *** findings offer theoretical insights that can guide the extensive utilization of porous structures in thermal control,management and thermal modulation.

关键词： near-field radiative heat transfer nanoporous GaN film surface phonon polaritons surface plasmon polaritons

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

Efficient and selective recovery of Gd(Ⅲ)via polyethyleneimine modification of lanthanum-based metal-organic frameworks

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Journal of Rare Earths 2024年第1期42卷 210-219,I0007页

作者： Wenhao Li Lijinhong Huang Bin Xiao Xiaoguang Duan Haike Li Lang Li Wanfu Huang Ganzhou Key Laboratory of Basin Pollution Simulation and Control Jiangxi University of Science and TechnologyGanzhou341000China Innovation Center for Water Quality Security Technology at Ganjiang River Basin Jiangxi University of Science and TechnologyGanzhou341000China Faculty of Science and engineering WA School of Mines:MineralsEnergy and Chemical EngineeringCurtin UniversityWAAustralia school of Architecture and Design Jiangxi University of Science and TechnologyGanzhou341000China school of Resources and architectural engineering Gannan University of Science and TechnologyGanzhou341000China school of Chemical engineering and Advanced Materials The University of AdelaideAdelaideSA5005Australia school of Resource and Environmental engineering Jiangxi University of Science and TechnologyGanzhou341000China

With the development of the economy and the increasing demand for environmental protection,the efficient and selective recovery of Gd(Ⅲ)from actual wastewater is of critical *** this work,lanthanum-based metal-organic framework(LaBDC)materials were prepared by a hydrothermal method,and then polyethyleneimine(PEI)and LaBDC were combined by an impregnation method to form a novel LaBDC@xPEI *** prepared materials were characterized using Fourier transfo rm infrared spectroscopy(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX),B runauer-Emmett-Teller(BET),thermogravimetric analysis(TGA)and X-ray photoelectron spectroscopy(XPS).Experiments show that LaBDC@50%PEI has the highest adsorption capacity(181.77 mg/g)among lanthanum-based MOFs with different PEI loadings at pH=5.5,which is about 5.1 times that of bare *** adsorption isotherm analysis shows that LaBDC@50%PEI follows the Langmuir *** addition,the adsorption kinetics of LaBDC@50%PEI follows a pseudo-second-order kinetic model,indicating that the adsorption process is chemical *** is worth noting that LaBDC@50%PEI maintains good adsorption performance and stability after three recycling tests,and exhibits excellent selectivity in cation interference ***,the LaBDC@50%PEI composites possess good stability and hold great promises in rapid recovery of Gd(Ⅲ)from practical aqueous environments.

关键词： Wet-impregnation method Polyethylene imine Metaleorganic frameworks Lanthanum Recovery of Gd(Ⅲ) Rare earths

3D Printed Polyimide/Silica Composite Aerogels for Customizable Thermal Insulation from-50℃ to 1300℃

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Chinese Journal of Polymer Science 2024年第7期42卷 936-945,I0007页

作者： Dingyi Yu Tiantian Xue Zhuocheng Ma Zaiyin Hu Lijuan Long Yue-E Miao Wei Fan Tianxi Liu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi214122China Guizhou Aerospace Wujiang Electro-Mechanical Equipment Co. Ltd.Zunyi563000China school of Materials and architectural engineering Guizhou Normal UniversityGuiyang550025China

Aerogels are widely used as thermal insulation materials because of their high porosity and low bulk ***,the insulation performance of aerogels is limited to a narrow temperature ***,the preparation of aerogel materials with precisely controlled and complex architectures is still ***,we report 3D printed polyimide/silica aerogel particle(PI/SAP)composite aerogels for thermal insulation in a wide range of temperature with customized *** printability and shape fidelity of 3D printed composite aerogels is improved by adding hydrophilic SAP as a rheology *** resulting PI/SAP composite aerogel exhibits excellent flame-retardant properties and thermal insulation from-50℃ to 1300℃.Moreover,the PI/SAP composite aerogel with customized shape can be applied for battery insulation at subzero temperatures,promising to be used as customizable and stable insulating materials in a variety of complex and extreme applications.

关键词： 3D printing Polyimide Aerogel Silica Thermal insulation

Bending Crashworthiness of Thin-Walled Square Tubes Partially Filled with Metallic Foams

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Journal of Harbin Institute of Technology(New series) 2024年

作者： Zhongyou Xie Limin Guo Cheng Li Jianwen Cai school of architectural engineering， Tongling University school of Science， Changzhou Institute of Technology school of Automotive engineering， Changzhou Institute of Technology

Two cross-sectional configurations of thin-walled square tubes partially filled with lightweight metallic foams are proposed， and termed as double-cell configuration partially filled with foam (DC-PF) and double-tube configuration partially filled with foam (DT-PF)， respectively. The bending crashworthiness is investigated based on three-point bending tests using finite element ABAQUS/Explicit code. The two key mechanical indicators including Crash Load Efficiency (CLE) and Specific Energy Absorption (SEA) are introduced to evaluate the effect of foams in comparison with empty square tubes and fully filled square tubes. The numerical results show that the two partially filled configurations， especially DT-PF， display dramatically excellent bending crashworthiness compared to empty and fully filled square tubes. There exists a foam density threshold， beyond which the CLE of DT-PF achieves a maximum constant. In addition， there seems to be another foam density threshold， beyond which the SEA of DT-PF gets to the maximum value. It is also shown that the foam density threshold corresponding to the maximum SEA varies with the thickness of thin-walled square tubes.

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Intelligent extraction of road cracks based on vehicle laser point cloud and panoramic sequence images

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Journal of Road engineering 2024年第1期4卷 69-79页

作者： Ming Guo Li Zhu Ming Huang Jie Ji Xian Ren Yaxuan Wei Chutian Gao school of Geomatics and Urban Spatial Informatics Beijing University of Civil Engineering and ArchitectureBeijing 102616China engineering Research Centre of Representative Building and architectural Heritage Database Ministry of EducationBeijing 100044China Key Laboratory of Modern Urban Surveying and Mapping National Administration of SurveyingBeijing 102616China school of Civil and Transportation engineering Beijing University of Civil Engineering and ArchitectureBeijing 102616China

In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strategy for extracting road *** methodology involves the integration of laser point cloud data obtained from a vehicle-mounted system and a panoramic sequence of *** study employs a vehicle-mounted LiDAR measurement system to acquire laser point cloud and panoramic sequence image data simultaneously.A convolutional neural network is utilized to extract cracks from the panoramic sequence *** extracted sequence image is then aligned with the laser point cloud,enabling the assignment of RGB information to the vehicle-mounted three dimensional(3D)point cloud and location information to the two dimensional(2D)panoramic ***,a threshold value is set based on the crack elevation change to extract the aligned roadway point *** three-dimensional data pertaining to the cracks can be *** experimental findings demonstrate that the use of convolutional neural networks has yielded noteworthy outcomes in the extraction of road *** utilization of point cloud and image alignment techniques enables the extraction of precise location data pertaining to road *** approach exhibits superior accuracy when compared to conventional ***,it facilitates rapid and accurate identification and localization of road cracks,thereby playing a crucial role in ensuring road maintenance and traffic ***,this technique finds extensive application in the domains of intelligent transportation and urbanization *** technology exhibits significant promise for use in the domains of intelligent transportation and city development.

关键词： Road crack extraction Vehicle laser point cloud Panoramic sequence images Convolutional neural network