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Direct Yaw Moment Control for Distributed Drive Electric Vehicle Handling Performance Improvement

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 486-497页

作者： YU Zhuoping leng bo XIONG Lu FENG Yuan SHI Fenmiao School of Automotive Studies Tongji University Pan Asia Technical Automotive Center Co. Ltd.

For a distributed drive electric vehicle（DDEV） driven by four in-wheel motors, advanced vehicle dynamic control methods can be realized easily because motors can be controlled independently, quickly and precisely. And direct yaw-moment control（DYC） has been widely studied and applied to vehicle stability control. Good vehicle handling performance： quick yaw rate transient response, small overshoot, high steady yaw rate gain, etc, is required by drivers under normal conditions, which is less concerned, however. Based on the hierarchical control methodology, a novel control system using direct yaw moment control for improving handling performance of a distributed drive electric vehicle especially under normal driving conditions has been proposed. The upper-loop control system consists of two parts： a state feedback controller, which aims to realize the ideal transient response of yaw rate, with a vehicle sideslip angle observer; and a steering wheel angle feedforward controller designed to achieve a desired yaw rate steady gain. Under the restriction of the effect of poles and zeros in the closed-loop transfer function on the system response and the capacity of in-wheel motors, the integrated time and absolute error（ITAE） function is utilized as the cost function in the optimal control to calculate the ideal eigen frequency and damper coefficient of the system and obtain optimal feedback matrix and feedforward matrix. Simulations and experiments with a DDEV under multiple maneuvers are carried out and show the effectiveness of the proposed method： yaw rate rising time is reduced, steady yaw rate gain is increased, vehicle steering characteristic is close to neutral steer and drivers burdens are also reduced. The control system improves vehicle handling performance under normal conditions in both transient and steady response. State feedback control instead of model following control is introduced in the control system so that the sense of control intervention to drive

关键词： direct yaw moment control distributed drive electric vehicle handling performance improvement state feedback control

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新时代十年:我国油菜产业发展与路径选择

中国油料作物学报 2024年第2期46卷 228-235页

作者：李谷成牛秋纯冷博峰丁逸飞童婷范丽霞华中农业大学经济管理学院/农业经济研究所湖北武汉430070 农业农村部农村经济研究中心北京100810 武汉轻工大学管理学院湖北武汉430048

当前国产植物油自给率依然偏低,油菜作为我国重要的油料作物,国产菜籽油占国内油料作物产油量的约50%,对保障国家食用油供给安全具有重要作用。2012年“中央一号文件”首次全面部署农业科技,油菜产业在科技支撑的作用下取得了长足发展。... 详细信息

当前国产植物油自给率依然偏低,油菜作为我国重要的油料作物,国产菜籽油占国内油料作物产油量的约50%,对保障国家食用油供给安全具有重要作用。2012年“中央一号文件”首次全面部署农业科技,油菜产业在科技支撑的作用下取得了长足发展。2023年“中央一号文件”明确提出深入推进大豆和油料产能提升工程,统筹油菜综合性扶持措施,推行稻油轮作,大力开发利用冬闲田种植油菜。在系统梳理2012-2022年油菜产业发展变化的基础上,本文结合科技创新对油菜产业发展的支撑作用,对我国油菜发展面临的问题、制约因素和产业优势等进行全面分析,对我国油菜产业可持续发展提供可资借鉴的政策建议。

关键词：油菜产业油料产能产业链科技支撑食用油安全

Mass estimation method for intelligent vehicles based on fusion of machine learning and vehicle dynamic model

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Autonomous Intelligent Systems 2022年第1期2卷 50-59页

作者： Zhuoping Yu Xinchen Hou bo leng Yuyao Huang School of Automotive Studies Tongji UniversityShanghai201804China

Vehicle mass is an important parameter for motion control of intelligent vehicles,but is hard to directly measure using normal ***,accurate estimation of vehicle mass becomes *** this paper,a vehicle mass estimation method based on fusion of machine learning and vehicle dynamic model is *** machine learning method,a feedforward neural network(FFNN)is used to learn the relationship between vehicle mass and other state parameters,namely longitudinal speed and acceleration,driving or braking torque,and wheel angular *** dynamics-based method,recursive least square(RLS)with forgetting factor based on vehicle dynamic model is used to estimate the vehicle *** to the reliability of each method under different conditions,these two methods are fused using fuzzy *** tests under New European Driving Cycle(NEDC)condition are carried *** simulation results show that the estimation accuracy of the fusion method is around 97%,and that the fusion method performs better stability and robustness compared with each single method.

关键词： Vehicle mass estimation Machine learning Feedforward neural network Vehicle dynamics Intelligent vehicle

Deep reinforcement learning-based drift parking control of automated vehicles

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Science China(Technological Sciences) 2023年第4期66卷 1152-1165页

作者： leng bo YU YiZe LIU Ming CAO Lei YANG Xing XIONG Lu School of Automotive Studies Tongji University

Drift parking usually requires precise control of a vehicle by a professional driver,which can reflect the performance of the vehicle under critical *** obstacles to implementing this action include the high coupling between the longitudinal and lateral states,the high precision required for the vehicle initial state when the drift is triggered,and the difficulty in determining the reference state variables in the drift process.A two-segment drift parking control system is proposed in this *** the approaching control segment,the vehicle achieves the drift-triggered vehicle speed and pose,which relies on a pathtracking algorithm based on linear time-varying model predictive *** the drifting control segment,the deep reinforcement learning algorithm twin-delayed deep deterministic policy gradient is creatively introduced to the controller *** solves the precise vehicle motion control problem under the condition of the rear wheels having locked *** various simulations,the superiority and robustness to different initial conditions and abrupt changes in the parking space are *** effectiveness of the proposed control system is verified by a ground test.

关键词： automated vehicles deep reinforcement learning drifting control vehicle dynamics control

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中老年人羽毛球体能训练策略研究

当代体育科技 2024年第16期14卷 35-38,43页

作者：唐嘉凯杨晓光冷波郭璟琦北京体育大学竞技体育学院北京体育大学中国游泳运动学院北京100084

全民健身背景下,羽毛球体育赛事日益增多,吸引了广大中老年人的积极参与。然而,随年龄增加,中老年人身体机能下降,进而导致羽毛球伤病风险增加,运动能力下降,运动寿命缩短。基于此,该文分析中老年人生理特点,并结合羽毛球项目特征提出... 详细信息

全民健身背景下,羽毛球体育赛事日益增多,吸引了广大中老年人的积极参与。然而,随年龄增加,中老年人身体机能下降,进而导致羽毛球伤病风险增加,运动能力下降,运动寿命缩短。基于此,该文分析中老年人生理特点,并结合羽毛球项目特征提出适合中老年人的羽毛球体能训练策略。中老年人运动系统、心血管系统、心肺系统的变化会导致羽毛球运动能力的降低,并且容易出现各种羽毛球急性、慢性损伤和运动性病症;策略设计需要符合中老年人生理特点、贴近生活实际、满足不同训练目的,并要求中老年人羽毛球体能训练遵循因人而异和循序渐进的原则。综上,提出中老年人的羽毛球体能训练策略:预防损伤为主的养护性体能训练;维持比赛能力为主的综合性体能训练;提高运动表现为主的专项体能训练。提出建议:老年人体能训练体系还需要进一步完善,可以通过开发适老性体能训练器材、编写适老性体能训练指南、设计适老性体能训练动作来促进中老年体能训练的良好开展。

关键词：中老年人体能训练羽毛球体育赛事

Robust Identification of Road Surface Condition Based on Ego‑Vehicle Trajectory Reckoning

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Automotive Innovation 2022年第4期5卷 376-387页

作者： Cheng Tian bo leng Xinchen Hou Yuyao Huang Wenrui Zhao Da Jin Lu Xiong Junqiao Zhao School of Automotive Studies Tongji UniversityShanghaiChina College of Electronic and Information Engineering Tongji UniversityShanghaiChina

The type of road surface condition(RSC)will directly affect the driving performance of *** the type of RSC is essential for both transportation agencies and individual ***,most existing methods are solely based on a dynamics-based method or an image-based method,which is susceptible to road excitation limitations and interference from the external ***,this paper proposes a decision-level fusion identification framework of the RSC based on ego-vehicle trajectory reckoning to accurately obtain the type of RSC that the front wheels of the vehicle will ***,a road feature extraction model based on multi-task learning is conducted,which can simultaneously segment the drivable area and road cast ***,the optimized candidate regions of interest are classified with confidence levels by *** environmental interference,candidate regions of interest regarded as virtual sensors are fused by improved Dempster-Shafer evidence theory to obtain the fusion ***,the ego-vehicle trajectory reckoning module based on the kinematic bicycle model is added to the proposed fusion method to extract the RSC experienced by the front *** performance of the entire framework is verified on a specific dataset with shadow and split curve *** results reveal that the proposed method can identify the RSC with accurate predictions in real time.

关键词： Road surface identification Ego-Vehicle trajectory reckoning Multi-task learning Dempster-Shafer evidence theory Autonomous vehicle

Chitosan-graft-poly(L-glutamic acid) Hybrid Material and Its Self-assembly

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Chemical Research in Chinese Universities 2012年第5期28卷 921-925页

作者： LIU Ye-zhuo YAO Jin-rong CAO Heng leng bo-xun SHAO Zheng-zhong CHEN Xin State Key Laboratory of Molecular Engineering of Polymers Laboratory of Advanced MaterialsDepartment of Maeromoleeular ScienceFudan UniversityShanghai 200433P.R.China

Chitosan-graft-poly（L-glutamic acid）（CS-g-PGA） copolymer was successfully synthesized by grafting polymerization of γ-benzyl-L-glutamate N-carboxyanhydride onto the modified chitosan chains. The self-assembly behavior of such a CS-g-PGA amphiphilic copolymer was studied. The results show that spherical nanoparticles have been formed. The size of CS-g-PGA nanoparticles is found to be controlled by the grafting ratio of PGA. These bio-based polysaccharide/polypeptide hybrid nanoparticles with controllable size may have great potential application in biomedical fields, such as drug delivery systems.

关键词： Biopolymer Nanoparticle Graft copolymer Self-assembly

Dynamic adaptive spatio-temporal graph network for COVID-19 forecasting

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 769-786页

作者： Xiaojun Pu Jiaqi Zhu Yunkun Wu Chang leng Zitong bo Hongan Wang Institute of Software Chinese Academy of Sciences BeijingChina Ecovacs Robotics Co. Ltd.SuzhouJiangsuChina Automotive Software Innovation Center ChongqingChina

Appropriately characterising the mixed space-time relations of the contagion process caused by hybrid space and time factors remains the primary challenge in COVID-19 ***,in previous deep learning models for epidemic forecasting,spatial and temporal variations are captured separately.A unified model is developed to cover all spatio-temporal ***,this measure is insufficient for modelling the complex spatio-temporal relations of infectious disease transmission.A dynamic adaptive spatio-temporal graph network(DASTGN)is proposed based on attention mechanisms to improve prediction *** DASTGN,complex spatio-temporal relations are depicted by adaptively fusing the mixed space-time effects and dynamic space-time dependency *** dual-scale model considers the time-specific,space-specific,and direct effects of the propagation process at the fine-grained ***,the model characterises impacts from various space-time neighbour blocks under time-varying interventions at the coarse-grained *** performance comparisons on the three COVID-19 datasets reveal that DASTGN achieves state-of-the-art results with a maximum improvement of 17.092%in the root mean-square error and 11.563%in the mean absolute *** results indicate that the mechanisms of designing DASTGN can effectively detect some spreading characteristics of *** spatio-temporal weight matrices learned in each proposed module reveal diffusion patterns in various *** conclusion,DASTGN has successfully captured the dynamic spatio-temporal variations of COVID-19,and considering multiple dynamic space-time relationships is essential in epidemic forecasting.

关键词： adaptive COVID-19 forecasting dynamic intervention spatio-temporal graph neural networks

Single nucleus/cell RNA-seq of the chicken hypothalamicpituitaryovarian axis offers new insights into the molecular regulatory mechanisms of ovarian development

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Zoological Research 2024年第5期45卷 1088-1107页

作者： Dong leng bo Zeng Tao Wang Bin-Long Chen Di-Yan Li Zhuan-Jian Li School of Pharmacy Chengdu UniversityChengduSichuan 610106China College of Animal Science and Technology Sichuan Agricultural UniversityChengduSichuan 611130China College of Animal Science Xichang UniversityXichangSichuan 615000China College of Animal Science and Technology Henan Agricultural UniversityZhengzhouHenan 450046China

The hypothalamic-pituitary-ovarian(HPO)axis represents a central neuroendocrine network essential for reproductive *** its critical role,the intrinsic heterogeneity within the HPO axis across vertebrates and the complex intercellular interactions remain poorly *** study provides the first comprehensive,unbiased,cell type-specific molecular profiling of all three components of the HPO axis in adult Lohmann layers and Liangshan Yanying *** the hypothalamus,pituitary,and ovary,seven,12,and 13 distinct cell types were identified,*** indicated that the pituitary adenylate cyclase activating polypeptide(PACAP),follicle-stimulating hormone(FSH),and prolactin(PRL)signaling pathways may modulate the synthesis and secretion of gonadotropin-releasing hormone(GnRH),FSH,and luteinizing hormone(LH)within the hypothalamus and *** the ovary,interactions between granulosa cells and oocytes involved the KIT,CD99,LIFR,FN1,and ANGPTL signaling pathways,which collectively regulate follicular *** SEMA4 signaling pathway emerged as a critical mediator across all three tissues of the HPO ***,gene expression analysis revealed that relaxin 3(RLN3),gastrin-releasing peptide(GRP),and cocaine-and amphetamine regulated transcripts(CART,also known as CARTPT)may function as novel endocrine hormones,influencing the HPO axis through autocrine,paracrine,and endocrine *** analyses between Lohmann layers and Liangshan Yanying chickens demonstrated higher expression levels of GRP,RLN3,CARTPT,LHCGR,FSHR,and GRPR in the ovaries of Lohmann layers,potentially contributing to their superior reproductive *** conclusion,this study provides a detailed molecular characterization of the HPO axis,offering novel insights into the regulatory mechanisms underlying reproductive biology.

关键词： Chickens Single nucleus/cell transcriptome Hypothalamic-pituitary-ovarian axis Signal crosstalk Hormones