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Neural-Fuzzy-Based Adaptive Sliding Mode Automatic Steering Control of Vision-based Unmanned Electric Vehicles

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Chinese Journal of Mechanical Engineering 2021年第5期34卷 56-68页

作者： jinghua guo Keqiang Li Jingjing Fan Yugong Luo Jingyao Wang School of Aerospace Engineering Xiamen UniversityXiamen 361005China State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China School of Electrical and Control Engineering North China University of TechnologyBeijing 100144China

This paper presents a novel neural-fuzzy-based adaptive sliding mode automatic steering control strategy to improve the driving performance of vision-based unmanned electric vehicles with time-varying and uncertain parameters.Primarily,the kinematic and dynamic models which accurately express the steering behaviors of vehicles are constructed,and in which the relationship between the look-ahead time and vehicle velocity is revealed.Then,in order to overcome the external disturbances,parametric uncertainties and time-varying features of vehicles,a neural-fuzzy-based adaptive sliding mode automatic steering controller is proposed to supervise the lateral dynamic behavior of unmanned electric vehicles,which includes an equivalent control law and an adaptive variable structure control law.In this novel automatic steering control system of vehicles,a neural network system is utilized for approximating the switching control gain of variable structure control law,and a fuzzy inference system is presented to adjust the thickness of boundary layer in real-time.The stability of closed-loop neural-fuzzy-based adaptive sliding mode automatic steering control system is proven using the Lyapunov theory.Finally,the results illustrate that the presented control scheme has the excellent properties in term of error convergence and robustness.

关键词： Vision-based unmanned electric vehicles Automatic steering Neural-fuzzy adaptive sliding control Vehicle lateral dynamics

基于深度强化学习的网联混合动力汽车队列控制

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机械工程学报 2024年第2期60卷 262-271页

作者：郭景华李文昌王班王靖瑶厦门大学机电工程系厦门361102 同济大学汽车学院上海201804 厦门大学自动化系厦门361102

针对网联混合动力汽车队列具有混杂非线性、多动力源混合驱动等特点,提出基于深度强化学习的队列分层控制策略。首先,设计了队列模型预测控制器,基于车车通信获取的车辆状态求解约束条件下满足多性能目标的队列车辆最优期望加速度。其次... 详细信息

针对网联混合动力汽车队列具有混杂非线性、多动力源混合驱动等特点,提出基于深度强化学习的队列分层控制策略。首先,设计了队列模型预测控制器,基于车车通信获取的车辆状态求解约束条件下满足多性能目标的队列车辆最优期望加速度。其次,为提高车辆的燃油经济性,将发动机最优工作曲线和电池特性曲线作为专家知识嵌入深度强化学习算法中。然后,通过分析电池荷电状态、车辆车速以及车辆加速度对智能体动作值的影响来阐明基于深度强化学习(Deep Q network,DQN)的队列能量管理策略是如何根据动作值实现对队列中车辆多系统动力输出之间的协调控制。最后,设计了以电池荷电状态、瞬时燃油消耗率为自变量的奖励值函数,利用最小化损失函数,采用梯度下降法对DQN网络参数进行更新,通过深度强化学习算法实现网联混合动力汽车队列的能量管理控制。试验结果表明,所提出的队列控制策略可以动态规划出队列中车辆期望加速度,实时合理的分配发动机功率与电机功率,最终实现队列中车辆的节能行驶。

关键词：网联混合动力汽车队列深度强化学习模型预测控制节能行驶

The compositions,sources,and size distribution of the dust storm from China in spring of 2000 and its impact on the global environment

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Chinese Science Bulletin 2001年第11期46卷 895-901页

作者： guoshun Zhuang jinghua guo Hui Yuan Chengyi Zhao Beijing Normal Univ Ctr Atmospher Environm Study Beijing 100875 Peoples R China

The average mass concentration of the aerosols in Beijing during the dust storm in the spring of 2000 was -6000 μg · m-3, -30 times as high as that in the non-dust storm days. The enrichment factors of the pollution elements As, Sb and Se were higher than those in the non-dust storm days. This indicated that As, Sb and Se resulted from the pollution sources of those areas, through which the dust storm passed during their long-range transport, in addition to the local pollution sources in Beijing. The enrichment factors of the Pb, Zn, Cd and Cu were much less than those in the non-dust storm days, suggesting that the local pollution sources in Beijing area contributed to them mostly. The enrichment factors of elements Al, Fe, Sc, Mn, Na, Ni, Cr, V and Co were close to 1, showing that these elements originated from crust. The concentration of S in the dust storm was -10 μg · m-3,4 times as high as that in non-dust storm. S in the aerosols resulted from the adsorption of gaseous SO2 and the consequent

关键词： dust storm aerosols particles pollution sources trans- formation global change.

Why the hydrothermal fluorinated method can improve photocatalytic activity of carbon nitride

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Chinese Chemical Letters 2021年第1期32卷 277-281页

作者： Gang Zhao Yupeng Xing Shuhua Hao Xijin Xu Wenxuan Ma jinghua guo Laboratory of Functional Micro and Nano Materials and Devices School of Physics and TechnologyUniversity of JinanJi’nan 250022China

Carbon nitride(CN) photocatalysts have attracted much attention due to their excellent photocatalytic properties.And hydrothermal fluorination is a common method to improve the photocatalytic effect of CN photocatalyst.Here,the influence of the band gap was first revealed of fluorination and hydroxylation of CN photocatalyst based on the first theoretical principle.Here,the effect of fluorination and hydroxylation on the CN band gap was discussed for the first time using the first theoretical principle.With F atoms and OH doping,the band gap of CN was significantly improved,conduction band and valence band moved up.Then,F-CN photocatalyst with F atoms and OH was successfully synthesized by a hydrothermal fluorinated method.Next,the reasons why F-CN photocatalyst was more effective than that of traditional CN photocatalyst were fully discussed.From the photocatalytic effect of photocatalyst(12,593.2 μmolg^(-1) h^(-1)to the morphology(super-small nanosheets),structure(homojunctions),composition(metal-free),specific surface area(54.1 m^(2)/g),visible light absorption response(AQE is10.9% at 420 nm) and photo-induced carrier life(14.13 ns).Therefore,this work has a great guiding effect on the development of CN photocatalyst.

关键词： Carbon nitride Band gap Density-functional theory(DFT) Fluorination and hydroxylation Reasons Time-resolved photoluminescence spectra

In Situ/Operando(Soft) X-ray Spectroscopy Study of Beyond Lithium-ion Batteries

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Energy & Environmental Materials 2021年第2期4卷 139-157页

作者： Feipeng Yang Xuefei Feng Yi-Sheng Liu Li Cheng Kao Per-Anders Glans Wanli Yang jinghua guo Joint Center for Energy Storage Research Lemont IL 60439USA Advanced Light Source Lawrence Berkeley National LaboratoryBerkeley CA 94720USA Department of Chemistry and Biochemistry University of California Santa CruzSanta Cruz CA 95064USA

The lightweight,rechargeable lithium-ion battery is one of the dominant energy storage devices globally in portable electronics due to its high energy density,no memory effect,wide operating voltage,lightweight,and good charge efficiency.However,due to safety concerns,the depletion of lithium reserves,and the corresponding increase of cost,an alternative battery system becomes more and more desirable.To develop alternative battery systems with low cost and high material abundance,for example,sodium,magnesium,zinc,and calcium,it is important to understand the chemical and electronic structure of materials.Soft X-ray spectroscopy,for example,X-ray absorption spectroscopy(XAS),X-ray emission spectroscopy(XES),and resonant inelastic soft X-ray scattering(RIXS),is an element-specific technique with sensitivity to the local chemical environment and structural order of the element of interest.Modern soft X-ray systems enable operando experiments that can be applied to amorphous and crystalline samples,making it a powerful tool for studying the electronic and structural changes in electrode and electrolyte species.In this article,the application of in situ/operando(soft)X-ray spectroscopy in beyond lithium-ion batteries is reviewed to demonstrate how such spectroscopic characterizations could facilitate the interpretation of interfacial phenomena under in situ/operando condition and subsequent development of the beyond lithium-ion batteries.

关键词： (soft)X-ray spectroscopy beyond lithium-ion battery in situ/operando interface

二氯吡啶酸对辣椒的药害及复硝酚钠的缓解作用

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农药 2024年第5期63卷 363-370页

作者：王富豪郭婧华郝培培程有普天津农学院园艺园林学院天津300392 天津市绿亨化工有限公司天津300270

[目的]探究二氯吡啶酸飘移对邻作作物辣椒的药害影响以及复硝酚钠对其的缓解效果。[方法]以青云2号辣椒为试验试材,采用喷洒二氯吡啶酸稀释液的方法模拟药液飘移,喷施复硝酚钠后分别观察叶、茎组织变化并测定比较辣椒苗期叶片的抗氧化... 详细信息

[目的]探究二氯吡啶酸飘移对邻作作物辣椒的药害影响以及复硝酚钠对其的缓解效果。[方法]以青云2号辣椒为试验试材,采用喷洒二氯吡啶酸稀释液的方法模拟药液飘移,喷施复硝酚钠后分别观察叶、茎组织变化并测定比较辣椒苗期叶片的抗氧化酶活性和丙二醛、叶绿素、类胡萝卜素、谷胱甘肽含量。[结果]在施药后7 d内,随着二氯吡啶酸质量浓度升高,辣椒苗的药害症状加重,其叶片的MDA含量逐渐升高,CAT、POD、SOD活性和叶绿素、类胡萝卜素含量呈先升高后降低的趋势,GSH含量在施药后3~7 d内随质量浓度升高而降低。其中二氯吡啶酸质量浓度为0.016 g/L时,辣椒新叶畸形黄化,茎结构开始出现损伤,质量浓度为0.800 g/L时,施药后7 d,叶片畸形严重并出现部分干枯,茎结构的完整性被破坏,各项生理指标均显著低于对照组;喷施复硝酚钠缓解后,二氯吡啶酸质量浓度为0.016、0.040 g/L时,辣椒药害现象缓解明显,MDA含量降低,CAT、POD、SOD显著升高,叶绿素、类胡萝卜素、GSH含量升高;二氯吡啶酸浓度为0.800 g/L时,喷施复硝酚钠无明显缓解效果。[结论]二氯吡啶酸飘移会对邻作作物辣椒产生不同程度的药害,浓度越高,药害症状越重,喷施复硝酚钠能在一定程度上缓解二氯吡啶酸对辣椒的药害症状。

关键词：二氯吡啶酸辣椒飘移药害复硝酚钠

双端通信时延下网联车辆纵向队列的分布式控制器设计与分析

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汽车安全与节能学报 2024年第3期15卷 402-412页

作者：王靖瑶黄江山郭景华李克强厦门大学航空航天学院厦门361005 清华大学智能绿色车辆与交通全国重点实验室(原汽车安全与节能国家重点实验室)北京100084

网联车辆队列系统的双端通信时延会极大影响队列的控制性能,而且在极端情况下,甚至可能引发队列失稳、发生碰撞的现象。该文在充分考虑车云双端通信时延的基础上,提出了一种基于云的分布式控制算法。通过一定假设,对云控场景下的车辆队... 详细信息

网联车辆队列系统的双端通信时延会极大影响队列的控制性能,而且在极端情况下,甚至可能引发队列失稳、发生碰撞的现象。该文在充分考虑车云双端通信时延的基础上,提出了一种基于云的分布式控制算法。通过一定假设,对云控场景下的车辆队列使用采样控制系统的方法进行建模,将双端通信时延进行统一;使用Riccati不等式设计了状态反馈分布式控制器,使用Lyapunov-Razumikin定理分析了控制算法的渐近稳定性,进而得到时变时延上界与通信拓扑、耦合增益之间的关系。结果表明:存在一个合适的耦合增益使得所能容忍的时延上界最大,且通信拓扑Laplacian矩阵最大与最小特征值的比值与时延上界大小呈负相关的趋势。

关键词：云控制系统网联车辆队列时变时延双端通信时延

Carbon decorated Li_(3)V_(2)(PO_(4))_(3) for high-rate lithium-ion batteries:Electrochemical performance and charge compensation mechanism

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Journal of Energy Chemistry 2021年第2期30卷 124-131,I0005页

作者： Manling Ding Chen Cheng Qiulong Wei Yue Hu Yingying Yan Kehua Dai Jing Mao jinghua guo Liang Zhang Liqiang Maig Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&1 DevicesSoochow UniversitySuzhou 215123JiangsuChina Department of Materials Science and Engineering Fujian Key Laboratory of Materials GenomeCollege of MaterialsXiamen UniversityXiamen 361005FujianChina College of Chemistry Tianjin Normal UniversityTianjin 300387China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001HenanChina Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCA 94720United States Department of Chemistry and Biochemistry University of CaliforniaSanta CruzCA 95064United States State Key Laboratory of Advanced Technology for Materials Synthesis and Processing International School of Materials Science and EngineeringWuhan University of Technology.Wuhan 430070HubeiChina

Fast charging and high-power delivering batteries are highly demanded in mobile electronics,electric vehicles and grid energy storage,but there are full of challenges.The star-material Li_(3)V_(2)(PO_(4))_(3) is demonstrated as a promising high-rate cathode material meeting the above requirements.Herein,we report the carbon decorated Li_(3)V_(2)(PO_(4))_(3) (LVP/C) cathode prepared via a facile method,which displays a remarkable high-rate capability and long-term cycling performance.Briefly,the prepared LVP/C delivers a high discharge capacity of 122 mAh g^(-1)(-93% of the theoretical capacity) at a high rate up to 20 C and a superior capacity retention of 87.1% after 1000 cycles.Importantly,by applying a combination of X-ray absorption spectroscopy and full-range mapping of resonant inelastic X-ray scattering,we clearly elucidate the structural and chemical evolutions of LVP upon various potentials and cycle numbers.We show unambiguous spectroscopic evidences that the evolution of the hybridization strength between V and O in LVP/C as a consequence of lithiation/delithiation is highly reversible both in the bulk and on the surface during the discharge-charge processes even over extended cycles,which should be responsible for the remarkable electrochemical performance of LVP/C.Our present study provides not only an effective synthesis strategy but also deeper insights into the surface and bulk electrochemical reaction mechanism of LVP,which should be beneficial for the further design of high-performance LVP electrode materials.

关键词： Lithium-ion batteries Li_(3)V_(2)(PO_(4))_(3) Charge compensation mechanism X-ray absorption spectroscopy Resonant inelastic X-ray scattering

Impact of nutrient solutions under inorganic substrate soilless cultivation on plant growth,fruit yield and quality of tomato

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Technology in Horticulture 2022年第1期2卷 31-41页

作者： jinghua guo Yonggang Jiao Haizheng Xiong Ainong Shi Yubo Yang Lidong Feng Lingdi Dong Linqi Shi Institute of Cash Crops Hebei Academy of Agriculture and Forestry SciencesShijiazhuang 050051China Department of Horticulture University of ArkansasFayettevilleAR 72701USA

Soilless cultivation has been widely used in tomato(Solanum lycopersicum)production.The objectives of this research are to evaluate the impacts of five nutrient solutions under soilless cultivation on plant growth,fruit yield and fruit quality in tomatoes.Four experiments were conducted with six treatments(five nutrient solutions plus one control)in six-cherry tomato cultivars and two big fruited tomato cultivars and 12 traits were observed and evaluated.The results showed that each of the five solutions increased plant growth and fruit yield,and improved the fruit quality.Compared to the control,the nutrient solution treatments increased 91.3%for number of fruits on base fruit cluster,12.1%for height,and 26.3%for stem diameter in the 2017-experiment;17.1%for vitamin C,13.8%for soluble solids,and 20.8%for total soluble sugar content in 2018-experiment one;28.1%for number of fruit cluster,25.8%for fruit yield,9.4%for number of fruit per cluster,and 13.3%for single fruit weight in 2018-experiment two;and 27.7%for vitamin C,14.0%for soluble solids,18.1%for total soluble sugar content,and 14.6%for fruit yield in the 2019-experiment.The solution decreased the chemical nitrate content 16.2%in the 2018-experiment and 43.7%in the 2019-experiment,and decreased the fruit cracking rate by 87%.Treatment 2 with higher nutrient component content showed the best results of the five treatments.The significant high positive correlation among the beneficial traits,fruit yield,soluble solids,total soluble sugar content,and vitamin C,and high negative correlation between each of the four traits and nitrate content were observed,indicating that soilless cultivation can increase tomato yield with higher nutritional components and decreased nitrate content.This research provides useful information for utilizing nutrient solutions supplied to tomato soilless cultivation.

关键词： soil nitrate sugar