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基于随机森林的无源时差定位误差估计与误差修正算法

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计算机测量与控制 2025年第1期33卷 269-275,284页

作者：宋定宇张君毅中国电子科技集团公司第54研究所石家庄050081 河北省电磁频谱认知与管控重点实验室石家庄050081

针对无源时差定位算法在时差估计误差未知条件下,无法通过计算几何稀释因子准确估计定位误差的问题,提出基于随机森林的无源时差定位误差估计与误差修正算法,通过学习信号特征参数和定位信息与定位误差之间的映射关系,准确估计定位误差... 详细信息

针对无源时差定位算法在时差估计误差未知条件下,无法通过计算几何稀释因子准确估计定位误差的问题,提出基于随机森林的无源时差定位误差估计与误差修正算法,通过学习信号特征参数和定位信息与定位误差之间的映射关系,准确估计定位误差并对定位结果进行修正,实现高精度定位;通过匹配时差定位结果与参考源信息制作了测试数据集,并使用该数据集验证了所提算法的有效性;对各特征参数的重要性进行了定量分析,并验证了随机森林模型在时间上的泛化能力;实验结果表明,所提算法实现了在时差估计误差未知条件下对时差定位误差的准确估计,提高无源时差定位的精度,具有较高的工程应用价值。

关键词：无源定位时差定位随机森林误差估计误差修正

Microstructure-ionisation potential relationship analysis for understanding the molecular ionisation difference of natural esters during the impulse discharge via DFT calculation

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High Voltage 2024年第4期9卷 920-929页

作者： Jingwen zhang Jian Hao Wenyu Ye junyi zhang Ruijin Liao State Key Laboratory of Power Transmission Equipment Technology School of Electrical/EngineeringChongqing UniversityChongqingChina

Understanding the impulse discharge behaviour of natural ester(NE)is crucial for its safe application in high-voltage *** ionisation potential(IP)of triglycerides plays a significant role in the process of molecular ionisation during impulse discharge for *** correlation coefficients between molecular size,frontier orbital,electrostatic potential,polarity,and IP were *** the quantitative microstructure-IP model for triglycerides were built,which revealed that IP is strongly related to the highest occupied molecular orbital(HOMO)energy EHM,as well as the average value of positive electrostatic potential V_(p)(t),the average value of negative electrostatic potential V_(p)(-),and the surface area of negative electrostatic potential S(-).The HOMO and negative electrostatic potentials of saturated triglycerides are predominantly linked to the carbonyl O ***,in unsaturated triglycerides,the influence of C=C double bonds on HOMO and negative electrostatic potentials is more ***,the IP of unsaturated NE with C=C bonds is lower than that of saturated NE,rendering it more susceptible to ionisation under a strong electric field which is unfavourable for impulse breakdown *** structure-property correlation analysis is valuable for understanding ionisation mechanism during the impulse discharge breakdown of NE at the microscopic level.

关键词： electrostatic potential bonds

Large Spacing Array with Offset Phase Center Elements for Highly Integrated Applications

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China Communications 2022年第5期19卷 231-240页

作者： Hailing Jiang Hui Tian Shubo Dun junyi zhang State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China Hebei Key Laboratory of Electromagnetic Spectrum Cognition and Control the 54th Research Institute of CETCShijiazhuang 050081China

A scanning and uniform array architecture with large spacing,low complexity and high scalability is presented for high integration massive array *** is constructed by offset phase center elements arranged in a uniform and regular way,but its spacing can be larger than that of traditional *** ideal model of the offset phase center element is established and its far-field distribution is *** suppress grating lobes,the phase center of any element is designed to be movable without changing its physical *** genetic algorithm(GA),a new constraint condition limiting the number of phase center changes is proposed to solve the objective function of the minimum values of grating lobes(GLs)and side lobes(SLs).It is shown that the optimal results can be achieved by two changes of phase centers.A multimode circular patch is developed and designed,and characteristics of the offset phase center are analyzed and verified.A prototype array of 12×12 offset phase center elements is implemented based on multi-mode circular *** wave simulation results of radiation patterns show that the level of grating lobes is suppressed at least 7dB with 1.12λ spacing,while the scanning angle is 20°.

关键词： massive array offset phase center array grating lobe reduction genetic algorithm multi-mode circular patch

Bactericidal efficacy of slightly acidic electrolyzed water(SAEW)against Listeria monocytogenes planktonic cells and biofilm on food-contact surfaces

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Food Quality and Safety 2022年第2期6卷 225-233页

作者： Jianxiong Hao junyi zhang Xueqi Zheng Dandan Zhao College of Food Science and Biology Hebei University of Science and TechnologyShijazhuangChina

In the present study,the bactericidal efficacy of slightly acidic electrolyzed water(SAEW)against Listeria monocytogenes(***)planktonic cells and biofilm on food-contact surfaces including stainless steel and glass was systematically *** results showed that SAEW(pH 5.09 and available chlorine concentration(ACC)of 60.33 mg/L)could kill *** on food-contact surfaces completely in 30 s,a disinfection efficacy equal to that of NaCIO solutions(pH 9.23 and ACC of 253.53 mg/L).The results showed that long exposure time and high ACC contributed to the enhancement of the disinfection efficacy of SAEW on *** on food-contact ***,the log reduction of SAEW treatment presented an increasing tendency within the prolonging of treatment time when SAEW was used to remove the *** bioflm formed on stainless steel and glass surfaces,which suggested that SAEW could remove *** bio-film effectively and its disinfection efficacy is equal to(in the case of stainless steel)or higher than(in the case of glass)that of high-ACC NaCIO *** addition,the results of the crystal violet staining and scanning electron microscopy also demonstrated that SAEW treatment could remove the *** biofilm on food-contact surfaces.

关键词： Slightly acidic electrolyzed water Listeria monocytogenes,biofilm food-contact surface

Rocky desertification poverty in Southwest China:Progress,challenges and enlightenment to rural revitalization

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Journal of Geographical Sciences 2022年第7期32卷 1357-1382页

作者： ZUO Taian zhang Fengtai zhang junyi GAO Lei YU Shijie School of Tourism Management and Services Chongqing University of EducationChongqing 400067China School of Management Chongqing University of TechnologyChongqing 400054China School of Geography and Tourism Chongqing Normal UniversityChongqing 401331China CSIRO Waite CampusUrrbraeSA 5064Australia

Rocky desertification poverty(RDP)refers to rural poverty triggered or exacerbated by rocky desertification,which deprives farmers of opportunities for improving their financial conditions through agricultural *** China implements strategies including building a moderately prosperous society,targeted poverty alleviation,and rural revitalization,issues concerning RDP have become the work foci for the Chinese government and research hotspots for Chinese academic *** paper provides a thorough review of the history,progress,challenges and prospects based on decades of RDP studies in Southwest ***,we review the origin,definitions and historical development trends of *** nearly four decades,research on RDP can be framed as four stages:start-up,poverty alleviation and ecological reconstruction,rocky desertification comprehensive control and green *** find that RDP research progress appears to be directly related to the Chinese government’s policy support and decision-making in mitigating ***,previous findings are reviewed and summarised regarding four research aspects:relationship exploration between rocky desertification and rural poverty,mechanisms of rocky desertification for exacerbating poverty,strategies for eliminating RDP and anti-poverty benefit evaluations of rocky desertification control ***,the remaining challenges are identified and summarised,including the challenges of conducting theoretical research on RDP and consolidating achievements in eliminating *** find that while many achievements have been made in the study of RDP in recent decades,the completeness and systematism of the theoretical system remain weak,and the guidance for empirical research is still ***,this research is fundamental in achieving rural revitalization in rocky desertification *** key to eliminating RDP lies in scientific rural transformation *** that the karst ecological environment in

关键词： rocky desertification rural revitalization poverty alleviation green development research progress Southwest China

基于YOLOv5n-CND的矿用输送带异物检测

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工矿自动化 2025年第1期51卷 38-44页

作者：孙奥然赵培培杨迪张君逸于洪健中国矿业大学信息与控制工程学院江苏徐州221116 华北理工大学人工智能学院河北唐山063009

针对异物图像背景复杂、特征提取能力弱、粘连小目标的检测精度低、检测框定位及尺度失真等问题,提出了一种基于YOLOv5n-CND的矿用输送带目标检测算法。首先,采用C2f对特征金字塔进行优化,使用更少参数解决在井下异物图像采集背景复杂... 详细信息

针对异物图像背景复杂、特征提取能力弱、粘连小目标的检测精度低、检测框定位及尺度失真等问题,提出了一种基于YOLOv5n-CND的矿用输送带目标检测算法。首先,采用C2f对特征金字塔进行优化,使用更少参数解决在井下异物图像采集背景复杂且存在复杂目标干扰对小目标检测不敏感的问题;然后,采用归一化高斯瓦萨斯坦距离(NWD)回归损失函数替代CIoU,改善多尺度异物检测效果不佳的问题,实现粘连小目标的精准检测;最后,添加目标检测头(Dy Head),将尺度、空间和任务3种注意力机制结合,提高对异物轮廓的特征提取能力,增强对多尺度目标的适应能力。实验结果表明:YOLOv5n-CND的mAP@0.5、mAP@0.5∶0.95、参数量及检测速度分别为87.9%,55.9%,4.49×106个,85.5帧/s,满足煤矿井下异物检测需求;YOLOv5n-CND的mAP@0.5和mAP@0.5∶0.95较YOLOv5n分别提高了2.6%和3.4%,较YOLOv5s-CBAM分别提高了1.7%和3.8%;模型参数量在YOLOv5n的基础上略有提升,但较其他模型参数量均有所降低。选取异物与背景相近的细长检测物、光照比较低的锚杆检测物、大量煤矸石混杂的检测物、含有多个异物4种场景进行测试,结果表明:基于YOLOv5n-CND的矿用输送带异物检测算法未出现误检及重复检测的情况,漏检较少,检测框定位准确,对粘连小目标的处理效果更好,能够实现输送带异物的准确检测。

关键词：矿用输送带异物检测粘连小目标检测 YOLOv5n C2f模块归一化高斯瓦萨斯坦距离模块 Dy Head检测头

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Precipitation behaviors and mechanical properties of a solution-treated Mg-Gd-Nd-Zn-Zr alloy during equal-channel angular pressing process

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Journal of Magnesium and Alloys 2022年第1期10卷 257-266页

作者： Zhenzhen Gui Fen Wang junyi zhang Dexin Chen Zhixin Kang School of Mechanical and Electrical Engineering Guangzhou University230 Wai Huan Xi RoadGuangzhou Higher Education Mega CenterGuangzhou 510006China Guangdong Key Laboratory for Advanced Metallic Materials Processing School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou 510640China Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan University601 Hmmgpu Avenue WestGuangzhou 510632China

A magnesium alloy processed by equal-channel angular pressing (ECAP) exhibited excellent microstructure refinement and improved strength and *** comprehensive mechanical properties of magnesium alloys have supported the expansion of their applications in the automotive,aerospace,and biomedical ***,pre-treatment of a solution-treated Mg-2.9Gd-1.5Nd-0.3Zn-0.3Zr alloy was conducted to investigate the precipitate behavior and microstructure evolution during the ECAP process.β;phase grains quickly precipitated from the solution-treated alloy,which accelerated grain refinement and enhanced the ductility after the ECAP process,as compared to the as-cast alloy reported in our previous ***,spherical precipitates (~200 nm) and fine phases (~100 nm) precipitated along the stripe-like Zn;Zr;phase,which formed a kabap-like structure dispersing homogeneously in the solution-treated alloy during the ECAP *** to grain refinement,dislocations,sphericalβ;precipitates,and texture evolution,the solution-treated alloy after eight passes of ECAP exhibited good comprehensive mechanical properties,with the ultimate tensile strength,yield strength,and elongation values reaching210.9 MPa,263.9 MPa,and 27.9%,respectively.

关键词： Mg-Gd-Nd-Zn-Zr alloy Precipitations Solid solution ECAP Mechanical properties

Zeolite-encaged Ultrasmall Pt-Zn Species with Trace Amount of Pt for Efficient Propane Dehydrogenation

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Chemical Research in Chinese Universities 2023年第6期39卷 870-876页

作者： QU Ziqiang zhang Tianjun YIN Xichen zhang junyi XIONG Xiaoyun SUN Qiming Innovation Center for Chemical Science College of ChemistryChemical Engineering and Materials ScienceJiangsu Key Laboratory of Advanced Negative Carbon TechnologiesSoochow UniversitySuzhou 215123P.R.China College of Chemistry and Materials Science Hebei UniversityBaoding 071002P.R.China PetroChina Lanzhou Petrochemical Company Lanzhou 730000P.R.China Lanzhou Petrochemical Research Center Petrochemical Research InstitutePetroChinaLanzhou 730000P.R.China

Propane dehydrogenation(PDH)has become a globe-welcoming technology to meet the massive demand for propylene,but the most commonly used Pt-based catalysts suffer from quick sintering,poor selectivity for propylene,and unsatisfied Pt ***,a series of Silicalite-1(S-1)zeolite-encaged ultrasmall Pt-Zn clusters with a trace amount of Pt[40—180 ppm(parts per million)]were developed by using a one-pot ligand-protected direct H_(2) reduction ***,the extremely low amount of Pt can significantly promote the activity of zeolite-encaged Zn catalysts in PDH *** to the high Pt dispersion,the synergy between Pt and Zn species,and the confinement effect of zeolites,the optimized PtZn@S-1 catalyst with 180 ppm Pt and 1.88%(mass fraction)Zn,exhibited an extraordinarily high propane conversion(33.9%)and propylene selectivity(99.5%)at 550℃with a weight hourly space velocity(WHSV)of 8 h^(-1),affording an extremely high propylene formation rate of 340.7 mol_(C_(3)H_(6))·g_(Pt^(-1))·h^(-1).This work provides a reference for the preparation of zeolite-encaged metal catalysts with high activity and noble metal utilization in PDH reactions.

关键词： Propane dehydrogenation Zeolite Confinement effect Bimetallic catalyst Pt-Zn

A dynamic speed guidance method at on-ramp merging areas of urban expressway considering driving styles

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Frontiers of Engineering Management 2024年第1期11卷 92-106页

作者： Haoran LI Yunpeng LU Yaqiu LI junyi zhang School of Automobile and Traffic Engineering Wuhan University of Science and TechnologyWuhan 430065China Suzhou Automotive Research Institute Tsinghua UniversitySuzhou 215134China School of Transportation Southeast UniversityNanjing 211189China Graduate School of Advanced Science and Engineering Hiroshima UniversityHigashi Hiroshima 739-8529Japan

Dynamic speed guidance for vehicles in on-ramp merging zones is instrumental in alleviating traffic congestion on urban *** enhance compliance with recommended speeds,the development of a dynamic speed-guidance mechanism that accounts for heterogeneity in human driving styles is *** intelligent connected technologies that provide real-time vehicular data in these merging locales,this study proposes such a guidance ***,we integrate a multi-agent consensus algorithm into a multi-vehicle framework operating on both the mainline and the ramp,thereby facilitating harmonized speed and spacing ***,we conduct an analysis of the behavioral traits inherent to drivers of varied styles to refine speed planning in a more efficient and reliable ***,we investigate a closed-loop feedback approach for speed guidance that incorporates the driver’s execution rate,thereby enabling dynamic recalibration of advised speeds and ensuring fluid vehicular integration into the *** results substantiate that a dynamic speed guidance system incorporating driving styles offers effective support for human drivers in seamless mainline merging.

关键词： driving styles speed guidance driving safety assistance on-ramp merging