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Science China(Information Sciences) 2021年第7期64卷 104-116页

作者： Hongbo GAO Hang SU Yingfeng CAI renfei WU Zhengyuan HAO Yongneng XU Wei WU Jianqing WANG Zhijun li Zhen KAN Department of Automation University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China The Dipartimento di Elettronica Informazione e Bioingegneria Politecnico di Milano Automotive Engineering Research Institute Jiangsu University College of Traffic and Transportation Southeast University School of Automation Nanjing University of Science and Technology School of Vehicle and Mobility Tsinghua University

Cyclist trajectory prediction is of great significance for both active collision avoidance and path planning of intelligent vehicles. This paper presents a trajectory prediction method for the motion intention of cyclists in real traffic scenarios. This method is based on dynamic Bayesian network(DBN) and long short-term memory(LSTM). The motion intention of cyclists is hard to predict owing to potential large uncertainties. The DBN is used to infer the distribution of cyclists’ intentions at intersections to improve the prediction time. The LSTM with encoder-decoder is used to predict the cyclists’ trajectories to improve the accuracy of prediction. Therefore, the DBN and LSTM are adopted to guarantee prediction accuracy and improve the prediction time. The experiment results are presented to show the effectiveness of the predict strategies.

关键词： trajectory prediction dynamic Bayesian network (DBN) long short-term memory (LSTM) unsignalized intersections motion intention

li-air batteries:air stability of lithium metal anodes

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Science China Chemistry 2024年第1期67卷 122-136页

作者： renfei Cao Kai Chen Jianwei liu Gang Huang Wanqiang liu Xinbo Zhang School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChangchun 130022China

Aprotic rechargeable lithium-air batteries(LABs)with an ultrahigh theoretical energy density(3,500 Wh kg^(-1))are known as the‘holy grail’of energy storage systems and could replace li-ion batteries as the next-generation high-capacity batteries if a practical device could be ***,only a few researches focus on the battery performance and reactions in the ambient air environment,which is a major obstacle to promote the practical application of ***,we have summarized the recent research progress on LABs,especially with respect to the li metal *** chemical and electrochemical deteriorations of the li metal anode under the ambient air are discussed in detail,and the parasitic reactions involving the cathode and electrolyte during the charge-discharge processes are *** also provide stability perspectives on protecting the li metal anodes and propose design principles for realizing high-performance LABs.

关键词： parasitic reaction lithium metal anode anode protection li-air batteries

MXenes induce epitaxial growth of size-controlled noble nanometals:A case study for surface enhanced Raman scattering(SERS)

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Journal of Materials Science & Technology 2020年第5期40卷 119-127页

作者： renfei Cheng Tao Hu Minmin Hu Changji li Yan liang Zuohua Wang Hui Zhang Muchan li Hailong Wang Hongxia Lu Yunyi Fu Hongwang Zhang Quan-Hong Yang Xiaohui Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling College of Mechanical EngineeringYanshan UniversityQinhuangdao 066004China Department of Materials Science and Engineering Monash UniversityClaytonVictoria 3800Australia Institute of Microelectronics Key Laboratory of Microelectronic Devices and CircuitsPeking UniversityBeijing 100871China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China School of Chemical Engineering&Technology Tianjin UniversityTianjin 300072China

Noble nanometals are of significance in both scientific interest and technological applications,which are usually obtained by conventional wet-chemical *** surfactants are always used in the synthesis to prevent unexpected overgrowth and aggregation of noble ***,the surfactants are hard to remove and may interfere with plasmonic and catalytic studies,remaining surfactant-free synthesis of noble nanometals a ***,we report an approach to epitaxial growth of sizecontrolled noble nanometals on *** piloted by density functional theory calculations,along with work function experimental determination,kinetic and spectroscopic studies,epitaxial growth of noble nanometals is initiated via a mechanism that involves an in situ redox *** the redox,MXenes as two-dimensional solid reductants whose work functions are compatible with the reduction potentials of noble metal cations,enable spontaneous donation of electrons from the MXenes to noble metal cations and reduce the cations into nanoscale metallic metals on the outmost surface of *** surfactants nor external reductants are used during the whole synthesis process,which addresses a long-standing interference issue of surfactant and external reductant in the conventional wet-chemical ***,the MXenes induced noble nanometals are ***,noble nanometals firmly anchored on MXenes exhibit excellent performance towards surface enhanced Raman *** developed strategy will promote the nanostructure-controlled synthesis of noble nanometals,offering new opportunities to further improve advanced functional properties towards practical applications.

关键词： Two-dimensional materials MXene In situ redox Noble metal SERS

Ecogeographical variation of 12 morphological traits within Pinus tabulaeformis: the effects of environmental factors and demographic histories

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Journal of Plant Ecology 2017年第2期10卷 386-396页

作者： Mingfei Ji Jianming Deng Buqing Yao renfei Chen Zhexuan Fan Jiawei Guan Xiaowei li Fan Wu Karl J.Niklas State Key Laboratory of Grassland and Agro-Ecosystems School of Life ScienceLanzhou University222 Tianshui RoadLanzhouGansu 730000China School of life Science and Technology Nanyang Normal University1638 Wolong RoadNanyangHenan 473061China Department of Plant Biology School of Integrative Plant ScienceCornell UniversityIthacaNY 14853USA

Aims More data are needed about how genetic variation(GV)and envi-ronmental factors influence phenotypic variation within the natural populations of long-lived species with broad geographic *** fill this gap,we examined the correlations among envi-ronmental factors and phenotypic variation within and among 13 natural populations of Pinus tabulaeformis consisting of four demo-graphically distinct groups within the entire distributional *** Using the Akaike’s information Criterion(AiC)model,we measured 12 morphological traits and constructed alternative candidate models for the relationships between each morphological trait and key climatic variables and genetic *** then compared the AiC weight for each candidate model to identify the best approximating model for ecogeographical variation of *** partitioning of vari-ance was assessed subsequently by evaluating the independent vari-ables of the selected best models using partial redundancy *** Findings Significant phenotypic variation of the morphological traits was observed both within individual populations and among *** partition analyses showed that most of the phenotypic variation was co-determined by both GV and climatic *** accounted for the largest proportion of reproductive trait variation,whereas local key climatic factors(*** evapotranspiration,AET)accounted for the largest proportion of phenotypic variation in the remaining investigated *** results indicate that both genetic divergence and key environmental factors affect the phenotypic variation observed among populations of this species,and that reproductive and vegetative traits adaptively respond differently with respect to local environmental *** partitioning of factors can inform those making predictions about phenotypic variation in response to future changes in climatic conditions(particularly those affecting AET).

关键词： Akaike’s Information Criterion environmental factors genetic variation information-theoretic approach phenotypic variation

Gel electrolyte via in situ polymerization to promote durable lithium-air batteries

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Chinese Chemical Letters 2023年第12期34卷 366-370页

作者： renfei Cao Kai Chen Yangfeng Cui Jianwei liu Wanqiang liu Gang Huang Xinbo Zhang School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institution of Applied ChemistryChinese of Academy of SciencesChangchun 130022.China

Aprotic lithium-air batteries(LABs)have been known as the holy grail of energy storage systems due to their extremely high energy ***,their real-world application is still hindered by the great challenges from the li anode side,like dendrite growth and corrosion reactions,thus a pure oxygen atmosphere is usually adopted to prolong the lifetime of LABs,which is a major obstacle to fully liberate the energy density advantages of ***,a gel polymer electrolyte has been designed through in-situ polymerization of 1,3-dioxolane(DOL)by utilizing the unique semi-open nature of LABs to protect the li anode to conquer its shortcomings,enabling the high-performance running of LABs in the ambient *** common liquid electrolytes,the in-situ formed gel polymer electrolyte could facilitate constructing a gradient SEl film with the gradual decrease of organic components from top to bottom,preventing the li anode from dendrite growth and air-induced corrosion reactions and thus realizing durable li repeated plating/stripping(2000h).Benefiting from the anode protection effects of the gradient SEI film,the LABs display a long lifetime of 17o cycles,paving an avenue for practical,long-term,and high-efficiency operation of LABs.

关键词： In situ polymerization Gel electrolyte Gradient sei film lithium anode lithium-air batteries

应用XGBoost算法的随机缺失地震数据重建

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石油地球物理勘探 2024年第5期59卷 965-975页

作者：李山田仁飞刘涛成都理工大学地球物理学院四川成都610059 大庆油田有限责任公司呼伦贝尔分公司黑龙江大庆163712

随着勘探目标的构造和地表地质条件的日趋复杂,地震数据经常存在不规则和不完整的问题,给后续的处理带来严重困难。针对这一难题,文中提出了一种基于XGBoost算法的地震数据重建方法。该方法从局部学习的角度出发,针对随机缺失的地震道,... 详细信息

随着勘探目标的构造和地表地质条件的日趋复杂,地震数据经常存在不规则和不完整的问题,给后续的处理带来严重困难。针对这一难题,文中提出了一种基于XGBoost算法的地震数据重建方法。该方法从局部学习的角度出发,针对随机缺失的地震道,在其周围选择一定数量的相邻地震道作为参考。通过构建这些参考地震道的道号、采样点号与数值之间的回归模型,能够精确学习并重建出缺失地震道的数据。为全面评估该方法的性能,对模拟数据不同地震道缺失情况下进行了实验,并与基于U-net卷积神经网络和基于凸集投影的Curvelet算法等重建方法进行比较。实验结果表明,基于XGBoost算法的重建方法对随机缺失地震数据重建具有较高的精度。实际数据处理结果表明,该方法能够为后续地震资料处理提供高精度的规则炮集数据。

关键词：地震数据重建 XGBoost 算法凸集投影机器学习 U-net

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水力机械空化实时检测技术研究

大电机技术 2024年第3期 69-76页

作者：赵越曹卫华滕海波李任飞郭一通赵英男刘智良苏文涛杜清玭孙永鑫哈尔滨电机厂有限责任公司哈尔滨150040 北京中水科工程集团有限公司北京100048 南水北调东线智能水务(北京)有限公司北京100071 哈尔滨工业大学哈尔滨150006 辽宁石油化工大学辽宁抚顺113005 中国三峡建工(集团)有限公司成都610095 哈尔滨大电机研究所有限公司哈尔滨150040

本文从空化现象的发生机理出发,开发出通过分析水力机械发生空化时辐射出的空化噪声时频特征的变化,判定水力机械空化发生及表征空化发生程度的实时检测技术。该技术已应用在包括贯流式、轴流式、混流式和水泵水轮机等水力机械型式的多... 详细信息

本文从空化现象的发生机理出发,开发出通过分析水力机械发生空化时辐射出的空化噪声时频特征的变化,判定水力机械空化发生及表征空化发生程度的实时检测技术。该技术已应用在包括贯流式、轴流式、混流式和水泵水轮机等水力机械型式的多个电站,具有安装便捷、安全可靠的特点,可以应用在水力机械优化运行和智慧机组建设等领域。

关键词：水力机械空化实时检测机组振动空化噪声

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基于XGBoost算法的v_(P)/v_(S)预测及其在储层检测中的应用

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石油地球物理勘探 2024年第4期59卷 653-663页

作者：田仁飞李山刘涛景洋成都理工大学地球物理学院四川成都610059 中国石油大庆油田公司呼伦贝尔分公司黑龙江大庆163712

鄂尔多斯盆地碳酸盐岩地层蕴含着丰富的油气资源。在勘探实践中发现,大牛地气田马家沟组断层发育、断距小,类型多样且成因复杂,给勘探、开发带来了较多挑战。为了应对这些挑战,提高储层预测的精度变得至关重要。在分析大牛地气田敏感弹... 详细信息

鄂尔多斯盆地碳酸盐岩地层蕴含着丰富的油气资源。在勘探实践中发现,大牛地气田马家沟组断层发育、断距小,类型多样且成因复杂,给勘探、开发带来了较多挑战。为了应对这些挑战,提高储层预测的精度变得至关重要。在分析大牛地气田敏感弹性参数的基础上,建立地震属性与储层纵横波速度比(v_(P)/v_(S))的关系,提出一种基于XGBoost算法的地震多属性v_(P)/v_(S)预测方法。为了进一步提升XGBoost算法的预测精度和泛化能力,采用贝叶斯算法对XGBoost算法的超参数进行优化,从而找到最佳的超参数组合,以确保模型在训练集和测试集上的性能均能得到提升。将XGBoost算法应用于Marmousi 2模型进行横波速度预测,预测值与实际值相关系数超过0.88,而均方误差、平均绝对百分比误差分别低于6.55×10^(-7)和4%,验证了该方法的准确性和可靠性。在鄂尔多斯盆地大牛地气田,应用该方法获得的v_(P)/v_(S)成功识别出含气储层,结果与实际钻井数据一致。理论模型和实际数据应用结果表明,XGBoost作为一种强大的机器学习算法预测精度较高,为直接由叠后地震属性预测v_(P)/v_(S)提供了一种有效的途径。

关键词：横波速度碳酸盐岩储层地震属性 XGBoost算法纵横波速度比(v_(P)/v_(S))

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Structure and emission behavior of a temperature sensitive composite sensor

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Structure and emission behavior of a temperature sensitive c...

基于持续无监督域适应策略的水面漂浮物目标检测方法

河南省化学会2016年学术年会

作者： Yu li Zong Chen Yaolong Zhang renfei Cao Qianyu li Xiaomeng Cheng Hongping li College of Chemistry and Molecular Engineering Zhengzhou University

In this work, we prepared an amphiphilic diblock copolymer poly(N-isopropylacrylamide)-block-poly(4-vinylpyridine)(PNIPAM-b-P4VP) which could respond to both temperature and p H stimuli in aqueous solution by reversible addition-fragmentation chain transfer(RAFT) *** structure and molecular weight of the copolymer were characterized by H NMR and GPC. The self-assembled fluorescent composite(SAFC) was formed between PNIPAM-b-P4 VP and the dye *** we studied the properties of the SAFC by fluorescence(FL) spectroscopy and FTIR. FTIR confirmed that hydrogen bonds were formed between the copolymer and dye molecules. The FL intensity of SAFC remains constant below 34℃, whereas shows FL enhancement above 35℃(Fig.1B).The FL intensity shows a swift enhancement with temperature until 41 ℃, and then a slow increase above 41℃. The particle size of the SAFC was characterized by dynamic light scattering(DLS), which suggests that the PNIPAm chains start to dehydrate at 34 ℃, from a elongated state to a highly coiled conformation with increasing temperature. The accompanying size shrinking of the SAFC micelles hampers the intra-molecular rotation of the fluorescent unit, thus weakens the non-radiative decay, and leads to the more emissive SAFC. So the FL enhancement is found to be associated with a heat-induced polymer chain conformation transition. And the SAFC is expected to have a potential application in controlled drug delivery.

关键词： PNIPAM-b-P4VP SAFC temperature-responsive polymer sensor

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系统工程与电子技术 2023年第11期45卷 3391-3401页

作者：陈任飞彭勇李忠文大连理工大学水利工程学院辽宁大连116024 大连理工大学经济管理学院辽宁大连116024

针对漂浮物检测中小尺度目标和域转移问题,提出一种基于持续无监督域适应策略的漂浮物检测方法。该方法通过删除低分辨率特征图,增强高分辨率特征图,提升小尺度漂浮物的特征提取能力。同时,该方法整合无监督域适应、缓冲区和样本重放,... 详细信息

针对漂浮物检测中小尺度目标和域转移问题,提出一种基于持续无监督域适应策略的漂浮物检测方法。该方法通过删除低分辨率特征图,增强高分辨率特征图,提升小尺度漂浮物的特征提取能力。同时,该方法整合无监督域适应、缓冲区和样本重放,降低应用场景中不断变化的域转移差异。并将改进检测网络与持续无监督域适应相结合,提升模型检测精度和泛化能力。通过在漂浮物数据集上实验验证,对比现有方法,该方法的检测精度达到82.2%,检测速度达到68.5 f/s,浮点数的算量减少到33亿,模型大小达到25.3 MB,扩展了目标检测在水面视觉中的应用。

关键词：深度学习水面漂浮物目标检测无监督域适应持续学习