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关干加强路企直通运输组织的措施探计

减速顶与调速技术 2024年第2期 9-10,32页

作者：任智斌中国铁路太原局集团有限公司山西太原030013

太原局管内主要装卸车点以直通运输组织模式为主,为年运量持续稳定增长奠定了坚实的基础,本文主要在对太原局实践路企直通运输组织情况进行分析的基础上,总结了取得的效果和下一步值得思考的问题,同时对解决措施和对策进行了探讨。

关键词：路企直通运输组织装卸车点解决措施专用线

基于开关型霍尔的PMSM改进型位置检测策略

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电子测量技术 2024年第7期47卷 163-169页

作者：任志斌卢潇吴宇黄瑞海江西理工大学电气工程与自动化学院赣州341000

为了克服霍尔传感器的局限,利用低分辨率的信号实现更精确的位置检测,提出一种基于改进最小二乘法和积分型滑模观测器的混合控制策略。首先,利用改进型最小二乘法完成可靠起动与低转速下平稳运行;其次是到达指定切换速度,系统切换运行状... 详细信息

为了克服霍尔传感器的局限,利用低分辨率的信号实现更精确的位置检测,提出一种基于改进最小二乘法和积分型滑模观测器的混合控制策略。首先,利用改进型最小二乘法完成可靠起动与低转速下平稳运行;其次是到达指定切换速度,系统切换运行状态,通过改进最小二乘法对积分型滑模观测器进行不断校正,在减小系统的滞后与累积误差的同时,使输出的位置信号尽可能连续。最后通过改进型位置检测策略与传统一阶加速度位置检测策略进行对照试验,结果表明,所提出的改进型位置检测策略,在电机起动时的位置检测精度提高了30%以上,在电机中高速稳态时转速误差降低至0.5%以内,位置检测误差降低至1%以内,具有较高的位置检测精度。

关键词：永磁同步电机霍尔传感器最小二乘法积分型滑模观测器改进型位置检测法

长白山区4种针叶林有效叶面积指数遥感精细反演及空间分布规律

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林业科学 2024年第5期60卷 127-138页

作者：包广道刘婷张忠辉任志彬翟畅丁铭铭姜雪菲吉林省林业科学研究院长春130033 中国科学院东北地理与农业生态研究所长春130102 长春大学长春130022 北京林业大学北京100083

[目的]研究快速、准确、宏观获取不同森林类型有效叶面积指数(LAI_(e))的方法,探讨其空间分布规律,为中小尺度森林LAI_(e)遥感产品的开发提供新思路,为林业精细化监测和森林生态系统碳水循环模拟提供科学可靠的技术手段。[方法]以长白... 详细信息

[目的]研究快速、准确、宏观获取不同森林类型有效叶面积指数(LAI_(e))的方法,探讨其空间分布规律,为中小尺度森林LAI_(e)遥感产品的开发提供新思路,为林业精细化监测和森林生态系统碳水循环模拟提供科学可靠的技术手段。[方法]以长白山为研究区,基于Sentinel-2A多光谱影像,运用三维卷积神经网络提取研究区4种针叶林型(长白落叶松、樟子松、红松和红皮云杉)的空间分布;采用区分林型和全样本2种方案,分析样地实测LAI_(e)与7种植被指数(增强植被指数、反红边叶绿素指数、改进简单植被指数、归一化水体指数、归一化植被指数、土壤调节植被指数、简单植被指数)的相关关系;利用各林型对应的最优植被指数,构建区分林型和全样本LAI_(e)与植被指数的回归模型,并基于验证样本数据对比区分林型模型、全样本模型和PROSAIL模型在LAI_(e)反演中的精度表现;结合地理因子分析4种针叶林型LAI_(e)空间格局及变化规律。[结果]所有样本组中7种植被指数与相对的LAI_(e)均存在极显著相关关系(P<0.01),除增强植被指数(EVI)与红松LAI_(e)、简单植被指数(SR)与红皮云杉LAI_(e)外,相关系数均大于0.6,但组间LAI_(e)与不同植被指数相关性具有较大差异;红松、长白落叶松和樟子松LAI_(e)与反红边叶绿素指数(IRECI)相关性最高,红皮云杉、红松LAI_(e)分别与EVI、改进简单植被指数(MSR)相关性最高;4种不同林型模型比全样本模型的R2提高12.7%以上,RMSE降低34.5%;研究区内4种林型LAI_(e)范围在0.37~5.86之间,平均LAI_(e)由高至低依次为红松、长白落叶松、樟子松、红皮云杉。红松对海拔、坡度、坡向的变化最为敏感,红皮云杉、樟子松次之,长白落叶松最小。[结论]不同林型LAI_(e)与遥感植被指数的相关程度存在明显差异,区分林型构建回归模型能够提高LAI_(e)反演精度;区分林型后拟合的线性模型精度整体较PROSAIL模型和全样本模型更高,但LAI_(e)高值区域没有PROSAIL模型表现稳定;4种针叶林型LAI_(e)对地理因子变化的反应差异较大。本研究可为精细区分森林类型的中小尺度针叶林LAI_(e)遥感反演研究提供参考。

关键词：有效叶面积指数针叶树种森林类型卫星遥感空间分布规律

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消反峰电路对电磁阀性能的影响分析

火箭推进 2024年第2期50卷 113-121页

作者：范宇任志彬陈涛张思远蓝箭航天空间科技股份有限公司北京100176

电磁阀在航天器中应用广泛。消反峰电路是电磁阀控制系统中重要的组成部分,且对电磁阀的性能有显著影响。为了获得消反峰电路对电磁阀性能的影响,基于Maxwell软件对某轴流直动式电磁阀及其消反峰电路进行研究。通过将电磁阀某工况下的... 详细信息

电磁阀在航天器中应用广泛。消反峰电路是电磁阀控制系统中重要的组成部分,且对电磁阀的性能有显著影响。为了获得消反峰电路对电磁阀性能的影响,基于Maxwell软件对某轴流直动式电磁阀及其消反峰电路进行研究。通过将电磁阀某工况下的静态和瞬态仿真结果与试验数据进行对比,验证了仿真模型的有效性。同时仿真对比了有、无消反峰电路及不同消峰电阻下的电磁阀性能,得到释放响应时间随消峰电阻的增大而减小,而感应电动势随消峰电阻的增大而增大的规律,同时发现消峰电阻对电磁阀性能的影响存在一个转折点,选择此点作为电磁阀控制系统的设计点可以得到更优的方案,进而提出从消反峰电路角度优化电磁阀控制系统的方案,为电磁阀控制系统的优化设计提供参考。

关键词：消反峰电路电磁阀 Maxwell软件感应电动势响应时间

Effects of urban street trees on human thermal comfort and physiological indices: a case study in Changchun city, China

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Journal of Forestry Research 2022年第3期33卷 911-922页

作者： zhibin ren Hongbo Zhao Yao Fu Lu Xiao Yulin Dong Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102P.R.China Key Research Institute of Yellow River Civilization and Sustainable Development&Collaborative Innovation Center On Yellow River Civilization Jointly Built By Henan Province and Ministry of Education Henan UniversityKaifeng475001P.R.China School of Geography and Engineering of Land Resources Yuxi Normal UniversityYuxi653100P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China

Planting trees along urban streets is one of the most important strategies to improve the urban thermal ***,the net impacts of urban street trees on human thermal comfort and physiological parameters are still less *** three similar east-west orientated streets with different degrees of tree cover-low(13%),medium(35%),and high(75%),urban microclimatic parameters and human physiological indices for six male students were simultaneously measured on three cloudless days in summer *** results show that the differences in tree cover were predominant in influencing urban thermal environment and *** street with the highest tree cover had significantly lower physiological equivalent temperature(PET) and more comfortable than the other two *** frequency of strong heat stress(PET> 35℃) was 64%,11 %,and 0%,respectively,for streets with low,medium,and high tree *** the six male university students,human physiological indices varied greatly across the three streets with different tree *** blood pressure,diastolic blood pressure,and pulse rate increased with decreasing tree *** results also suggest that urban thermal environment and comfort had considerable impact on human physiological *** study provides reasons for urban planners to plant trees along streets to improve the thermal environment and promote urban sustainability.

关键词： Urban forest Green space Environmental ecosystem services Urban thermal comfort Blood pressure Pulse rate

Recreational Attractiveness of Urban Parks and Implications for Their Management:A Case Study in Changchun,China

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Chinese Geographical Science 2022年第3期32卷 456-466页

作者： MAO Zhixia WANG Wenjie ren zhibin ZHANG Dan HE Xingyuan Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China

Urban parks are an important part of urban ecosystems and also provide recreational services for urban ***,it is still unclear how the recreational attractiveness of urban parks can be *** this study,12 typical parks in Changchun,China were selected for evaluation of their recreational *** built a recreational attractiveness evaluation system based on the analytical hierarchy process(AHP)to produce a composite evaluation *** method included:1)the landscape quality of the parks;2)the recreational facilities;3)the conditions of the area;and 4)the accessibility of the *** results showed that Nanhu Park,Children’s Park,Shengli Park,and Jingyuetan Forest Park had high recreational attractiveness,whereas Linyuan Park had the lowest attractiveness among the 12 *** results agreed with the information obtained from a field survey of the actual recreational and revisit rates,which showed that the evaluation index is *** analysis showed that the landscape quality and recreational facilities of parks had a direct effect on their recreational attractiveness.A negative correlation was found between the accessibility of a park and its recreational *** conclude that if the scenery and facilities are not as good as a visitor expects,then they may choose to visit a different park,even if it takes a longer time to reach.

关键词： questionnaire survey analytic hierarchy process recreational attractiveness management implications perception of residents urban parks

Understanding the drivers of woody plant diversity in urban parks in a snow climate city of China

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Journal of Forestry Research 2023年第4期34卷 1021-1032页

作者： Zijun Ma Peng Zhang Nanlin Hu Guodong Wang Yulin Dong Yujie Guo Chengcong Wang Yao Fu zhibin ren Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China School of Geography and Engineering of Land Resources Yuxi Normal UniversityYuxi 653100People’s Republic of China

Urban parks are an important part of urban ecosystems and play an important role in biodiversity ***,it is still unclear how park characteristics aff ect plant diversity which could hinder the conservation of urban biodiversity due to the ineff ective design of urban *** diversity of woody plants in 33 parks of Changchun,China,was measured with plot measurements and linked with urban park characteristics(e.g.,size and age of the park)to uncover the relationship between *** results show that urban woody plant species were abundant,with 98 species belonging to 51 genera and 26 families in the snow climate city of *** variation in woody plant diversity was largely explained by internal patch characteristics(e.g.,size,age,shape),and external factors surrounding the park(e.g.,land use type and socioeconomic level)accounted for only 16.0%in our *** internal patch characteristics,older urban parks with larger areas demonstrated a richer level of plant diversity and increased nonlinearly with increasing park *** threshold size signifi cantly aff ecting plant diversity variation was approximately 30 *** diversity had positive linear relationships with the ages of urban parks,supporting the legacy eff *** addition,woody plant diversity nonlinearly decreased with increasing park shape index,which suggested that the plant diversity could also be increased by optimizing the park *** the external factors surrounding parks,the spatial distribution of woody plant diversity varied greatly from the urban center to the *** prices around the park had positive linear relationships with woody plant diversity in parks,supporting the luxury eff ***,building and road proportions,and green space proportion had no relationship with plant diversity in *** study can provide a robust reference for enriching plant diversity in urban parks,thus improving the development of urban sustainable cities.

关键词： Urban ecosystem Urban biodiversity Urban park Remote sensing Field measurement

Uncertainty-Aware Deep Learning: A Promising Tool for Trustworthy Fault Diagnosis

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1317-1330页

作者： Jiaxin ren Jingcheng Wen zhibin Zhao Ruqiang Yan Xuefeng Chen Asoke K.Nandi School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Electronic and Electrical Engineering Brunel University LondonKingston LaneUxbridgeUB83PHUK IEEE

Recently,intelligent fault diagnosis based on deep learning has been extensively investigated,exhibiting state-of-the-art ***,the deep learning model is often not truly trusted by users due to the lack of interpretability of“black box”,which limits its deployment in safety-critical applications.A trusted fault diagnosis system requires that the faults can be accurately diagnosed in most cases,and the human in the deci-sion-making loop can be found to deal with the abnormal situa-tion when the models *** this paper,we explore a simplified method for quantifying both aleatoric and epistemic uncertainty in deterministic networks,called *** SAEU,Multivariate Gaussian distribution is employed in the deep architecture to compensate for the shortcomings of complexity and applicability of Bayesian neural *** on the SAEU,we propose a unified uncertainty-aware deep learning framework(UU-DLF)to realize the grand vision of trustworthy fault ***,our UU-DLF effectively embodies the idea of“humans in the loop”,which not only allows for manual intervention in abnor-mal situations of diagnostic models,but also makes correspond-ing improvements on existing models based on traceability ***,two experiments conducted on the gearbox and aero-engine bevel gears are used to demonstrate the effectiveness of UU-DLF and explore the effective reasons behind.

关键词： Out-of-distribution detection traceability analysis trustworthy fault diagnosis uncertainty quantification.

基于TBS模式的重复经颅磁刺激联合虚拟现实治疗脑卒中单侧空间忽略的效果观察

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浙江医学 2024年第6期46卷 630-633,642页

作者：陶林花曾明任志彬李亮傅建明赵慧红嘉兴市第二医院康复医学中心 314000 嘉兴市王店人民医院针灸理疗科

目的探讨基于θ波爆发刺激(TBS)模式的重复经颅磁刺激(rTMS)联合虚拟现实治疗脑卒中后单侧空间忽略(USN)的效果。方法选择2021年6月至2022年6月嘉兴市第二医院康复医学中心收治的脑卒中USN患者60例,按随机数字表法分为观察组和对照组,每... 详细信息

目的探讨基于θ波爆发刺激(TBS)模式的重复经颅磁刺激(rTMS)联合虚拟现实治疗脑卒中后单侧空间忽略(USN)的效果。方法选择2021年6月至2022年6月嘉兴市第二医院康复医学中心收治的脑卒中USN患者60例,按随机数字表法分为观察组和对照组,每组30例。两组患者均给予常规药物、周围环境调整、USN宣教、针对USN的行为学治疗及虚拟现实治疗,观察组在上述治疗基础上再接受基于TBS模式的rTMS。分别于治疗前、治疗4周后采用线段消切试验、字母涂抹试验、二分线试验、临摹画图试验、凯瑟琳·伯格戈量表(CBS)、简易精神状态检查量表(MMSE)、改良Barthel指数(MBI)对两组患者的USN程度、行为学、认知功能和日常生活活动能力进行评估。结果两组患者治疗后的USN程度4项试验均优于治疗前,且观察组优于对照组,差异均有统计学意义(均P<0.01)。治疗后两组患者的CBS、MMSE及MBI评估指标均优于治疗前,且观察组优于对照组,差异均有统计学意义(均P<0.01)。结论基于TBS模式的rTMS联合虚拟现实治疗可有效缓解脑卒中患者的USN程度,改善其行为表现,同时可提高患者的认知功能及日常生活活动能力,其治疗效果优于单纯虚拟现实治疗。

关键词：重复经颅磁刺激虚拟现实脑卒中单侧空间忽略