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无人机激光雷达人工林林分高估测模型分析

遥感学报 2022年第12期26卷 2665-2678页

作者：李梅刘清旺冯益明李增元中国林业科学研究院资源信息研究所北京100091 国家林业和草原局林业遥感与信息技术重点实验室北京100091 中国林业科学研究院荒漠化研究所北京100091

中国人工林面积居世界第一,精确地对人工林结构进行监测具有重要意义。本研究以内蒙古自治区赤峰市旺业甸林场内的落叶松和油松人工林为研究对象,利用无人机激光雷达LiDAR(Light Detection And Ranging)离散点云数据和地面样地调查数据... 详细信息

中国人工林面积居世界第一,精确地对人工林结构进行监测具有重要意义。本研究以内蒙古自治区赤峰市旺业甸林场内的落叶松和油松人工林为研究对象,利用无人机激光雷达LiDAR(Light Detection And Ranging)离散点云数据和地面样地调查数据对人工林林分高进行建模,通过点云特征变量与地面测量的6种林分高(包括:Lorey’s高、算术平均高、最大高、优势树高、中位数高和树冠面积加权高)间的Pearson’s相关性筛选自变量,然后利用全子集回归构建不同林分高估测模型,并采用交叉检验法进行精度评价。结果表明:激光雷达点云高度百分位数与不同林分高相关性均较高,通过一元线性回归构建的不同林分高结果最优,且估测模型的自变量均为高度特征变量。Lorey’s高(R^(2)=0.91—0.97,rRMSE=2.75%—3.96%)、优势树高(R^(2)=0.86—0.97,rRMSE=3.72%—3.83%)和树冠面积加权高(R^(2)=0.86—0.96,rRMSE=3.81%—4.73%)估测精度最高,算术平均高(R^(2)=0.85—0.94,rRMSE=4.52%—6.07%)和中位数高(R^(2)=0.80—0.95,rRMSE=5.37%—7.34%)次之,最大高(R^(2)=0.69—0.87,rRMSE=6.19%—8.09%)最低。针对不同森林类型,落叶松人工林林分高估测精度最优,优于不区分森林类型模型的估测精度(ΔR^(2)=0—0.05,ΔrRMSE=-0.69%—1.97%),优于油松林林分高模型的估测精度(ΔR^(2)=0.06—0.18,ΔrRMSE=-1.90%—1.13%)。无人机激光雷达可以用于估测北方温带针叶林的林分高,能够满足人工林资源调查快速、精确的要求。

关键词：遥感无人机激光雷达点云人工林林分高

Field-Oriented Control and Direct Torque Control for a Five-Phase Fault-Tolerant Flux-Switching Permanent-Magnet Motor

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Chinese Journal of Electrical Engineering 2018年第4期4卷 48-56页

作者： Binyu Wu Dezhi Xu Jinghua Ji Wenxiang Zhao qingwang Jiang School of Electrical and Information Engineering Jiangsu UniversityZhenjiang 212013China Jiangsu Key Laboratory of Drive and Intelligent Control for Electric Vehicle Zhenjiang 212013China

This paper presents a comparative performance analysis of a new five-phase fault-tolerant flux-switching permanent-magnet(FT-FSPM)motor for high-reliability applications under the two most popular control schemes,namely,field-oriented control(FOC)and direct torque control(DTC)based on stator-flux ***,the new motor topology and structural characteristics are briefly ***,the d-and q-axis for the FT-FSPM motor are defined,which is crucial to the mathematical model and control scheme,and the mathematical models are ***,two control schemes,i.e.,FOC and DTC,and the main system are *** operational principles of the two control schemes are presented,and space vector pulse width modulation(SVPWM)based on four neighboring vectors is adopted to reduce current harmonics and torque ***,the simulated and experimental results are given,and performance analysis of the two control schemes are compared and *** results reveal that FOC scheme has the sinusoidal phase current and low torque ripples,while the DTC scheme has fast dynamic response,verifying the effectiveness of the two proposed control *** paper is a primary investigation for more possible improvements in the control schemes of the five-phase FS-FTPM motor.

关键词： Flux-switching five-phase motor permanent-magnet motor filed-oriented control direct torque control

Prognostic Predictor and Immune Microenvironment Signatures of Aberrant Exon Skipping Events in Triple-Negative Breast Cancer

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Prognostic Predictor and Immune Microenvironment Signatures ...

Putting the Cart before the Horse? Capital Account Liberalization and Exchange Rate Flexibility in China

2022CCTB中国肿瘤标志物学术大会暨中国整合肿瘤学...

作者： qingwang Chen Zehui Cao Ruolan Zhang Erfei Shang Qiaochu Chen Leming Shi Yuanting Zheng Fudan University

Background:Exon skipping(ES) is defined as the procedure of mature RNA processing where a selected exon is excluded from the *** one essential type of alternative splicing(AS) event,aberrant ES plays an important role in the pathogenesis of cancer and the formation of the tumor ***,characterization of aberrant ES profiles in the malignancy and prognosis of triple-negative breast cancer(TNBC) is little known and urgently ***:We quantified the percent spliced in(PSI) values for ES events in 360 tumor tissues and88 adjacent-normal tissues from the Fudan University Shanghai Cancer Center(FUSCC)TNBC ***,we performed differential comparative analysis to obtain cancer-associated ES events(CAES).Unsupervised cluster analysis was performed to analyze the characteristics of immune infiltration in the ***,univariate Cox and stepwise multivariate Cox regression analyses were conducted to find the prognosis associated with CAES and the best prognostic CAES ***,pathway enrichment and gene set enrichment analysis(GSEA) was further employed to reveal the significant pathways for prognosis-related CAES ***:A total of 277 CAES were identified(|delta PSI tumor-normal| > 0.10,FDR<0.05),including 101 up-regulated and 176 down-regulated in tumor *** of 241parent genes revealed 84 GO pathways with statistical significance(FDR<0.05),with the top pathways related to cell adhesion molecule binding,cell leading edge,*** clustering analysis with CAES identified three clusters with different immune microenvironment components,immune score,and stromal score in TNBC(P<0.05).Univariate and multivariate Cox regression analyses identified six CAES associated with better prognoses(P<0.05).Results of GSEA showed the CAES signature might confer a strong tumor metabolism phenotype in the high-risk group with elevated activities in folate biosynthesis and phospholipase D pathways

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China & World Economy 2005年第4期13卷 3-20页

作者： EswarPrasad ThomasRumbaugh qingwang ChiefoftheFinancialStudiesdivisionintheResearchDepartment anAdvisorintheIMF＇sAsiaandPacificDepartment andwasDeputyChiefofitsChinaDivisionwhenthispaperwaswritten aneconomistintheChinaDivision

This paper reviews the issues involved in moving towards greater exchange rate flexibilityand capital account liberalization in China. A more flexible exchange rate regime wouldallow China to operate a more independent monetary policy, providing a useful bufferagainst domestic and external shocks. At the same time, weaknesses in China’s financialsystem suggest that capital account liberalization poses significant risks and should be alower priority in the short term. This paper concludes that greater exchange rate flexibilityis in China’s own interest and that, along with a more stable and robust financial system, itshould be regarded as a prerequisite for undertaking a substantial liberalization of thecapital account.

关键词： capital controls exchange rate regime financial sector reforms

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基于集对云的机坪运行管理移交安全评价研究

中国安全生产科学技术 2022年第11期18卷 169-176页

作者：李明捷冯庆旺中国民用航空飞行学院机场学院四川广汉618307

为对航空器机坪运行管理移交下运行安全状况做出科学合理的评价,结合具体机场的机坪运行复杂性,首先引入PSR模型,从压力、状态和响应3个方面构建管理移交机场机坪运行安全评价指标体系;随后使用熵值法进行指标权重计算,并运用欧几里得... 详细信息

为对航空器机坪运行管理移交下运行安全状况做出科学合理的评价,结合具体机场的机坪运行复杂性,首先引入PSR模型,从压力、状态和响应3个方面构建管理移交机场机坪运行安全评价指标体系;随后使用熵值法进行指标权重计算,并运用欧几里得度量函数进行组合赋权;接着引入集对理论和云模型,结合组合权重使用正向云发生器确定综合云联系度,利用Python绘制等级云图,评判系统安全等级;最后以某大型机场为例进行验证。研究结果表明:本文所提出的机坪运行管理移交安全评估评价方法经验证与实际运行情况相符,能够为机坪运行安全评价提供理论参考。

关键词：机坪运行管理移交机坪运行安全评价 PSR模型欧几里得度量函数集对云模型

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地基与无人机激光雷达结合提取单木参数

农业工程学报 2022年第14期38卷 51-58页

作者：朱俊峰刘清旺崔希民张文博中国矿业大学(北京)地球科学与测绘工程学院北京100083 中国林业科学研究院资源信息研究所北京100091 国家林业和草业局林业遥感与信息技术重点实验室北京100091

激光雷达(Light Detection And Ranging,Li DAR)在森林空间结构测量方面具有较大优势,但单独利用地基或无人机Li DAR难以完整描述森林垂直结构。为此,该研究提出了地基和无人机Li DAR点云相结合的单木参数提取方法,采用相对最短路径算法... 详细信息

激光雷达(Light Detection And Ranging,Li DAR)在森林空间结构测量方面具有较大优势,但单独利用地基或无人机Li DAR难以完整描述森林垂直结构。为此,该研究提出了地基和无人机Li DAR点云相结合的单木参数提取方法,采用相对最短路径算法(Comparative Shortest-Path algorithm,CSP)和点云区域生长算法分别从地基和无人机Li DAR点云中识别单木,根据地基和无人机Li DAR的单木位置与地面实测单木位置进行点云粗匹配,然后采用迭代最近点(Iterative ClosestPoint,ICP)进行点云精匹配,采用最高值和基于密度的噪声应用空间聚类(Density-BasedSpatialClusteringof ApplicationswithNoise,DBSCAN)提取单木树高和胸径,并通过地面实测样地数据对地基、无人机和融合点云的单木参数提取精度进行评价。结果表明:基于地基和融合点云的单木检出率一致,简单、中等、复杂样地的单木检出率分别为98%、94%、91%,基于无人机点云的单木检出率较低;基于地基与融合点云的胸径提取精度基本一致,三种样地胸径提取值的决定系数R2均在0.96以上,均方根误差(Root Mean Square Error,RMSE)在1.20~1.60 cm之间;基于融合点云的树高提取精度最优,简单、中等、复杂样地树高提取值的R2分别为0.98、0.94和0.73,RMSE在1.38~4.19 m之间;融合点云对中等样地树高提取精度提升较大,融合后RMSE相较地基点云降低了0.34m,R^(2)提高了3%,对简单、复杂样地提升较小;所研究的单木中,杉木的胸径和树高提取精度最高,R2最高分别为0.99、0.89,RMSE最低分别为1.35 cm、1.96 m。地基和无人机Li DAR融合点云可以更精细地测量森林空间结构,更好地满足森林资源调查业务应用。

关键词：无人机激光雷达林业参数提取胸径树高

晚期非小细胞肺癌患者免疫治疗的预后相关因素分析

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实用肿瘤杂志 2023年第3期38卷 239-245页

作者：姚源山华青旺高文复旦大学华东医院胸外科上海老年医学重点实验室上海200041 中国科学院大学宁波华美医院胸外科浙江宁波315010

目的探讨影响接受免疫治疗的晚期非小细胞肺癌(non-small-cell lung cancer,NSCLC)患者预后的相关因素,为临床治疗提供参考。方法回顾性分析2019年6月至2020年6月复旦大学华东医院收治的64例接受单药程序性死亡受体-1(programmed cell d... 详细信息

目的探讨影响接受免疫治疗的晚期非小细胞肺癌(non-small-cell lung cancer,NSCLC)患者预后的相关因素,为临床治疗提供参考。方法回顾性分析2019年6月至2020年6月复旦大学华东医院收治的64例接受单药程序性死亡受体-1(programmed cell death-1,PD-1)/程序性死亡受体配体1(programmed cell death-ligand 1,PD-L1)抑制剂治疗的晚期NSCLC患者的临床资料及血液学指标。采用Cox单因素和多因素模型分析患者的预后相关因素。收集并记录免疫治疗的相关不良反应。结果所有患者的中位总生存期是10.4个月(95%CI:8.2~12.3个月)。多因素分析显示,ECOG评分、治疗线数、中性粒细胞与淋巴细胞比值(neutrophil-lymphocyte ratio,NLR)、血小板与淋巴细胞比值(platelet-lymphocyte ratio,PLR)、C反应蛋白和乳酸脱氢酶是影响患者无进展生存期的独立危险因素(均P<0.05)。ECOG评分、治疗线数、NLR、PLR和C反应蛋白是影响患者总生存期的独立危险因素(均P<0.05)。患者免疫治疗后不良反应发生率为48.4%(31/64),其中多数(43.8%,28/64)为1~2级,对症治疗后可好转。结论免疫治疗前NLR、PLR、C反应蛋白、ECOG评分和治疗线数与晚期NSCLC患者免疫治疗预后密切相关。NSCLC患者免疫治疗的不良反应发生率较高,但是相对安全。

关键词：晚期非小细胞肺癌免疫治疗预后免疫相关不良反应

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基于MobileNet的多尺度感受野特征融合算法

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激光与光电子学进展 2023年第4期60卷 270-278页

作者：黄裕凯王青旺沈韬朱艳宋健昆明理工大学信息工程与自动化学院云南昆明650500

针对轻量化网络在目标检测中检测精度低的问题,提出了一种以MobileNet为基础网络的轻量级目标检测网络MobileNet-RFB-ECA。针对目标多尺度特性,采用基于轻量化扩充感受野模块(RFB)的特征金字塔网络结构增强网络对目标多尺度特性的适应... 详细信息

针对轻量化网络在目标检测中检测精度低的问题,提出了一种以MobileNet为基础网络的轻量级目标检测网络MobileNet-RFB-ECA。针对目标多尺度特性,采用基于轻量化扩充感受野模块(RFB)的特征金字塔网络结构增强网络对目标多尺度特性的适应性。与此同时,针对复杂注意力模块导致计算量大的问题,在主干特征提取网络添加有效通道注意力机制模块(ECA),提高卷积神经网络的性能。实验结果表明,相较于MobileNet,所提MobileNet-RFB-ECA在PASCAL VOC数据集和KITTI数据集上检测精度分别提高了4.2个百分点和15.4个百分点,模型大小分别为50.3 MB和48.5 MB,平均检测速度为34 frame·s^(-1)。

关键词：图像处理目标检测轻量化神经网络多尺度特征融合 MobileNet RFB-Net模型有效注意力机制

Perpendicular magnetic anisotropy of Pd/Co_(2)MnSi/NiFe_(2)O_(4)/Pd multilayers on F-mica substrates

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Chinese Physics B 2022年第1期31卷 568-572页

作者：白青旺郭斌尹钦王书运 School of Physics and Electronics Shandong Normal UniversityJi'nan 250358China

Pd/Co_(2)MnSi(CMS)/NiFe_(2)O_(4)(NFO)/Pd multilayers were fabricated on F-mica substrate by magnetron *** best PMA performance of the multilayer structure Pd(3 nm)/CMS(5 nm)/NFO(0.8 nm)/Pd(3 nm)was obtained by adjusting the thickness of the CMS and NFO layers.F-mica substrate has a flatter surface than glass and Si/SiO_(2) *** magnetic anisotropy energy density(K_(eff))of the sample deposited on F-mica substrates is 0.6711 Merg/cm^(3)(1 erg=10^(-7) J),which is about 30%higher than that of the multilayer films deposited on glass(0.475 Merg/cm^(3))and Si/SiO_(2)(0.511 Merg/cm^(3))substrates,and the R_(Hall) and H_(C) are also significantly *** this study,the NFO layer prepared by sputtering in the high purity Ar environment was exposed to the high purity O_(2) atmosphere for 5 min,which can effectively eliminate the oxygen loss and oxygen vacancy in NFO,ensuring enough Co-O orbital hybridization at the interface of CMS/NFO,and thus effectively improve the sample PMA.

关键词： perpendicular magnetic anisotropy Co_(2)MnSi ferrimagnetics NiFe_(2)O_(4)