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Advances in Atmospheric Sciences 2020年第3期37卷 269-277页

作者： xiaoxu tian Xiaolei ZOU Earth Science System Interdisciplinary Center University of Maryland

The second Advanced Technology Microwave Sounder(ATMS)was onboard the National Oceanic and Atmospheric Administration(NOAA)-20 satellite when launched on 18 November *** nearly six months of the earliest NOAA-20 observations,the biases of the ATMS instrument were compared between NOAA-20 and the Suomi National Polar-Orbiting Partnership(S-NPP)*** biases of ATMS channels 8 to 13 were estimated from the differences between antenna temperature observations and model simulations generated from Meteorological Operational(MetOp)-A and MetOp-B satellites’Global Positioning System(GPS)radio occultation(RO)temperature and water vapor *** was found that the ATMS onboard the NOAA-20 satellite has generally larger cold biases in the brightness temperature measurements at channels 8 to 13 and small standard *** observations from ATMS on both S-NPP and NOAA-20 are shown to demonstrate an ability to capture a less than 1-h temporal evolution of Hurricane Florence(2018)due to the fact that the S-NPP orbits closely follow those of NOAA-20.

关键词： ATMS NOAA-20 S-NPP biases calibration Hurricane Florence

Striping Noise Analysis and Mitigation for Microwave Temperature Sounder-2 Observations

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Advances in Atmospheric Sciences 2019年第7期36卷 711-720页

作者： Xiaolei ZOU xiaoxu tian Earth Science System Interdisciplinary Center University of Maryland College Park

The Microwave Temperature Sounder(MWTS)-2 has a total of 13 temperature-sounding channels with the capability of observing radiance emissions from near the surface to the stratosphere. Similar to the Advanced Technology Microwave Sounder(ATMS), striping pattern noise, primarily in the cross-track direction, exists in MWTS-2 radiance observations. In this study, an algorithm based on principal component analysis(PCA) combined with ensemble empirical mode decomposition(EEMD) is described and applied to MWTS-2 brightness temperature observations. It is arguably necessary to smooth the first three principal component(PC) coefficients by removing the first four intrinsic mode functions(IMFs) using the EEMD method(denoted as PC3/IMF4). After the PC3/IMF4 noise mitigation, the striping pattern noise is effectively removed from the brightness temperature observations. The noise level in MWTS-2 observations is significantly higher than that detected in ATMS observations. In May 2014, the scanning profile of MWTS-2 was adjusted from varying-speed scanning to constantspeed scanning. The impact on striping noise levels brought on by this scan profile change is also analyzed here. The striping noise in brightness temperature observations worsened after the profile change. Regardless of the scan profile change, the striping noise mitigation method reported in this study can more or less suppress the noise levels in MWTS-2 observations.

关键词： MWTS-2 striping noise temperature sounding microwave radiometry

A Limb Correction Method for the Microwave Temperature Sounder 2 and Its Applications

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Advances in Atmospheric Sciences 2018年第12期35卷 1547-1552页

作者： xiaoxu tian Xiaolei ZOU Shengpeng YANG Earth Science System Interdisciplinary Center University of Maryland College Park Joint Center for Data Assimilation Research and Applications Nanjing University of Information Science and Technology

The Microwave Temperature Sounder 2(MWTS-2)is a cross-track radiometer that has 13 channels of sampling radiances emitted from different vertical levels of the *** of the varying scan angles of each field of view within a scan line,observations from the MWTS-2 are subject to strong scan-position-dependent features,i.e.,the limb *** examining brightness temperatures(TBs),weather signals observed at every temperature-sounding channel are often concealed by scan-dependent *** study,therefore,proposes a limb correction method to remove scan-dependent features so that the underlying weather signals can be ***-corrected TBs can be used to monitor large-scale patterns over the globe as well as extreme weather events such as ***-corrected TBs are also more correlated with atmospheric physical variables such as temperature and liquid water path.

关键词： MWTS-2 Limb Correction Tropical cyclones weather monitoring

Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect

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Journal of Mountain Science 2024年第3期21卷 1058-1074页

作者： CHENG Yun SONG Zhanping XU Zhiwei YANG Tengtian tian xiaoxu School of Civil Engineering Yancheng Institute of TechnologyYancheng 224051China School of Civil Engineering Xi'an University of Architecture and TechnologyXi'an 710055China Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering Xi'an 710055China China Railway Construction Bridge Engineering Bureau Group Co. Ltd.Tianjin 300300China

The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass.

关键词： Hard siltstone Failure mechanism Stratification effect Infrared radiation characteristic Temporal-damage mechanism Dissimilation

A non-ACE2 competing human single-domain antibody confers broad neutralization against SARS-CoV-2 and circulating variants

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Signal Transduction and Targeted Therapy 2021年第12期6卷 3645-3652页

作者： Zhenlin Yang Yulu Wang Yujia Jin Yuanfei Zhu Yanling Wu Cheng Li Yu Kong Wenping Song Xiaolong tian Wuqiang Zhan Ailing Huang Shanshan Zhou Shuai Xia xiaoxu tian Chao Peng Cuicui Chen Yibing Shi Gaowei Hu Shujuan Du Yuyan Wang Youhua Xie Shibo Jiang Lu Lu Lei Sun Yuanlin Song tianlei Ying Department of Pulmonary Medicine Zhongshan HospitalFudan UniversityShanghai 200032China Shanghai Engineering Research Center for Synthetic Immunology Shanghai 200032China Shanghai Key Laboratory of Lung Inflammation and Injury Shanghai 200032China MOE/NHC Key Laboratory of Medical Molecular Virology Shanghai Institute of Infectious Disease and BiosecuritySchool of Basic Medical SciencesShanghai Medical CollegeFudan UniversityShanghai 200032China The Fifth People’s Hospital of Shanghai Fudan University and Shanghai Key Laboratory of Medical EpigeneticsInstitutes of Biomedical SciencesFudan UniversityShanghai 200032China National Facility for Protein Science in Shanghai Zhangjiang LabShanghai Advanced Research InstituteChinese Academy of ScienceShanghai 201210China Department of Pulmonary Medicine Shanghai Respiratory Research InstituteShanghai 200032China

The current COVID-19 pandemic has heavily burdened the global public health system and may keep simmering for *** frequent emergence of immune escape variants have spurred the search for prophylactic vaccines and therapeutic antibodies that confer broad protection against SARS-CoV-2 *** we show that the bivalency of an affinity maturated fully human singledomain antibody(n3113.1-Fc)exhibits exquisite neutralizing potency against SARS-CoV-2 pseudovirus,and confers effective prophylactic and therapeutic protection against authentic SARS-CoV-2 in the host cell receptor angiotensin-converting enzyme 2(ACE2)humanized *** crystal structure of n3113 in complex with the receptor-binding domain(RBD)of SARS-CoV-2,combined with the cryo-EM structures of n3113 and spike ecto-domain,reveals that n3113 binds to the side surface of up-state RBD with no competition with *** binding of n3113 to this novel epitope stabilizes spike in up-state conformations but inhibits SARS-CoV-2 S mediated membrane fusion,expanding our recognition of neutralization by antibodies against *** assay and pseudovirus neutralization assay show no evasion of recently prevalent SARS-CoV-2 lineages,including Alpha(B.1.1.7),Beta(B.1.351),Gamma(P.1),and Delta(B.1.617.2)for n3113.1-Fc with Y58L mutation,demonstrating the potential of n3113.1-Fc(Y58L)as a promising candidate for clinical development to treat COVID-19.

关键词： ACE2 variants authentic

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基于FPGA的微弱信号检测与实现技术

重庆邮电大学学报（自然科学版） 2016年第3期28卷 297-302页

作者：高振斌田晓旭河北工业大学电子信息工程学院天津300401

研究了杜芬混沌振子(Duffing chaos oscillator)微弱信号检测算法及其现场可编程门阵列(field programmable gate arrays,FPGA)实现技术。根据杜芬系统在混沌和大周期2种状态下相图的明显区别,运用基于相图分割的信号检测方法,在FPGA上... 详细信息

研究了杜芬混沌振子(Duffing chaos oscillator)微弱信号检测算法及其现场可编程门阵列(field programmable gate arrays,FPGA)实现技术。根据杜芬系统在混沌和大周期2种状态下相图的明显区别,运用基于相图分割的信号检测方法,在FPGA上实现了杜芬混沌算法与系统状态判别方法的结合。根据并行运算与流水线原理,对杜芬方程的结构进行调整。采用递推数列的方法计算正弦值,以便节约存储空间。使用VHDL硬件语言设计了杜芬阵子系统中核心的四阶龙格库塔(fourth order Runge Kutta algorithm,RK4)模块和状态检测模块,在vivado集成开发环境下仿真验证了设计的正确性。通过改变策动力的频率,系统可以检测各种频率的微弱正弦信号。经判断,该系统可实现对与系统信号同频率信号的检测。

关键词：微弱信号检测现场可编程门阵列(FPGA) 杜芬混沌阵子递推数列

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原发中枢神经系统淋巴瘤的治疗进展

中国肿瘤临床 2022年第20期49卷 1047-1051页

作者：田晓旭赵冉周可树郑州大学附属肿瘤医院河南省肿瘤医院血液科郑州市450003

原发中枢神经系统淋巴瘤(primary central nervous system lymphoma,PCNSL)是仅累及脑实质、脊髓、眼、颅神经及脑膜,无中枢神经(central nervous system,CNS)以外部位受累的一类结外非霍奇金淋巴瘤。目前,治疗主要是以大剂量甲氨蝶呤... 详细信息

原发中枢神经系统淋巴瘤(primary central nervous system lymphoma,PCNSL)是仅累及脑实质、脊髓、眼、颅神经及脑膜,无中枢神经(central nervous system,CNS)以外部位受累的一类结外非霍奇金淋巴瘤。目前,治疗主要是以大剂量甲氨蝶呤为基础的化疗,联合大剂量化疗/自体干细胞移植(autologous stem cell transplantation,auto-HSCT)或减量的全脑放疗。但缓解率较低,不良反应较大。研究显示,10%~15%的患者对诱导化疗原发耐药,即使治疗有效,仍有50%的患者复发。近年来,PCNSL遗传学和分子的研究极大地促进了生物学机制的理解。小分子药物和靶向药物治疗的前景可观,有望减少不良反应的同时,提高患者缓解率、延长寿命。本文主要对目前PCNSL的新治疗方向进行综述。

关键词：原发中枢神经系统淋巴瘤靶向治疗小分子药物免疫治疗

角色压力对慢性病患者移动医疗服务付费意愿的影响研究

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管理学报 2021年第8期18卷 1220-1228页

作者：杨一毫毕新华田晓旭吉林大学管理学院长春市130022

基于压力与应对视角,探讨慢性病患者日常健康管理中面临的角色压力对移动医疗服务付费意愿的影响机理。采用结构方程和分层回归法,结合压力与应对理论构建模型,以358位慢性病患者为样本进行实证研究。研究表明:角色模糊和角色冲突激发... 详细信息

基于压力与应对视角,探讨慢性病患者日常健康管理中面临的角色压力对移动医疗服务付费意愿的影响机理。采用结构方程和分层回归法,结合压力与应对理论构建模型,以358位慢性病患者为样本进行实证研究。研究表明:角色模糊和角色冲突激发了慢性病患者的应对策略(医患关系维持和健康管理能力提升);应对策略对移动医疗服务付费意愿有显著影响;同时,角色压力能否以及多大程度对行为结果产生影响,依赖于慢性病患者对压力的初级评价和次级评价。

关键词：角色压力压力与应对理论慢性病患者移动医疗服务付费意愿

基于改进YOLOv4的地面鸡蛋识别算法研究

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中国家禽 2023年第6期45卷 61-67页

作者：胡宇涛赵广元田晓旭西安邮电大学自动化学院陕西西安710199 西安市先进控制与智能处理重点实验室陕西西安710199

为实现散养模式下智能收集地面鸡蛋的需求,研究提出一种基于改进YOLOv4的地面鸡蛋识别算法,基于原YOLOv4目标识别算法,通过添加SENet模块增强识别算法获取目标特征的能力,裁剪路径聚合网络分支加快特征提取速度,使用soft-NMS算法降低漏... 详细信息

为实现散养模式下智能收集地面鸡蛋的需求,研究提出一种基于改进YOLOv4的地面鸡蛋识别算法,基于原YOLOv4目标识别算法,通过添加SENet模块增强识别算法获取目标特征的能力,裁剪路径聚合网络分支加快特征提取速度,使用soft-NMS算法降低漏检率,提高模型的准确率。结果显示,改进后的YOLOv4算法相比于Faster-RCNN和YOLOv3算法,mAP分别提高了12.2%、5.68%,识别速度分别提高了29.45FPS、1.23FPS;与YOLOv4算法相比,改进后的YOLOv4算法提高了识别效率,mAP提升了2.08%,识别速度为41.49FPS。结果表明,改进后的YOLOv4目标识别算法能够快速准确地识别出弱光条件下以及复杂环境中的地面鸡蛋,改善了地面鸡蛋因被遮挡而产生的漏检问题,为地面鸡蛋采集等装置提供了视觉技术支持。

关键词：蛋鸡智慧养殖卷积神经网络地面鸡蛋识别

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考虑拱效应的隧道管棚力学模型与参数分析

地下空间与工程学报 2023年第1期19卷 95-106,132页

作者：许晓静宋战平李辉田小旭周冠南西安建筑科技大学土木工程学院西安710055 陕西省岩土与地下空间工程重点实验室西安710055 中国铁建大桥工程局集团有限公司天津300300

为了更好地研究隧道管棚的实际受力状态,根据隧道施工工序和施工影响,将隧道管棚划分为二衬段、初支段、开挖段以及掌子面前方的扰动段和未扰动段等五段,考虑管棚注浆后形成整体管棚拱的拱效应,建立了五段式隧道管棚的Winkler弹性地基... 详细信息

为了更好地研究隧道管棚的实际受力状态,根据隧道施工工序和施工影响,将隧道管棚划分为二衬段、初支段、开挖段以及掌子面前方的扰动段和未扰动段等五段,考虑管棚注浆后形成整体管棚拱的拱效应,建立了五段式隧道管棚的Winkler弹性地基梁新模型,推导了五段式隧道管棚模型的挠度和内力计算公式,并与既有工程案例进行对比分析,同时对不同的开挖进尺、管棚直径和加固区弹性模量进行了分析。结果表明:新模型得到的管棚挠度最大值和挠度最大值对应的位置与现场监测结果更为接近,能够解决已有管棚模型因边界条件设置不合理而造成的管棚变形在扰动段的末端出现的上拱现象,更符合管棚实际的变形情况;改变开挖进尺对管棚的挠度影响更大,管棚钢管直径为108 mm和114 mm时,其管棚支护效果相差不大;当Ec(加固区弹性模量)>40.0 Eg(围岩弹性模量)时,开挖进尺和钢管直径对管棚的挠度和弯矩的影响不大,因此,提高加固区的弹性模量是减小管棚挠度和内力最有效的方法。

关键词：隧道工程管棚拱效应弹性地基梁参数分析