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Atmospheric and Oceanic Science Letters 2014年第3期7卷 198-202页

作者： cai zhao-nan LIU Yi LIU Xiong Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences Harvard-Smithsonian Center for Astrophysics

The authors analyzed the retrieval sensitivity of tropospheric ozone using simulated the Global Ozone Monitoring Experiment-2 （GOME-2） measurements. The retrieval sensitivity was evaluated by the degree of free- dom for signal （DFS）. The combination of the ultraviolet （UV）, UV polarization （UVPOL）, and visible （VIS） bands enhances DFS of tropospheric ozone and improves the vertical resolution of the retrieved ozone profile. UVPOL reduces the dependence on solar zenith angle, mainly in- creases the sensitivity in upper troposphere. Polarization increased the DFS by 20% on the eastern side of the GOME-2 orbit, with little improvement on the western side because the increase in DFS due to polarization is depend- ent on the relative azimuth angle. The inclusion of the visi- ble band reduces significantly the dependence on viewing geometry, and mainly increases the DFS in the lower tro- posphere （0-6 kin） by a factor of two. It was possible to retrieve several independent pieces of tropospheric ozone information from GOME-2 UV/UVPOL/VIS measure- ments, especially in the lower troposphere.

关键词： tropospheric ozoneretrieval sensitivity GOME-2

Simulations of Aerosol Optical Properties to Top of Atmospheric Reflected Sunlight in the Near Infrared CO_2 Weak Absorption Band

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Atmospheric and Oceanic Science Letters 2013年第1期6卷 60-64页

作者： YANG Dong-Xu LIU Yi cai zhao-nan Key Laboratory of the Middle Atmosphere and Global Environmental Observation(LAGEO) Institute of Atmospheric Physics(IAP)Chinese Academy of Sciences

Over the Asian continent,high aerosol loading is critical to ensure the high accuracy of CO_2 retrieval in the near infrared absorption *** were performed to explore the effect of light path modification by aerosol son the atmospheric CO_2 near infrared band(6140-6270 cm^(-1)).The Vector LInearized Discrete Ordinate Radiative Transfer(VLIDORT) model and the Line-By-Line Radiative Transfer Model(LBLRTM) were used for forward *** *** atmosphere was used for atmospheric *** results indicate that the aerosols caused similar effects to increases in CO_2 in the planetary boundary layer and became more significant with aerosol layer rising while aerosol optical depth was *** effect will cause an over estimation of the CO_2 mixing ratio in the retrieval process and an under estimation in the aerosol *** results also indicate that the effect of urban and industrial aerosols is smaller than that of non-absorbing and dust aerosols because of the nearly constant absorption properties in the near infrared band.

关键词： satellite remote sensing CO2 near infrared aerosol

Sensitivity of the simulated CO2 concentration to inter-annual variations of its sources and sinks over East Asia

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Advances in Climate Change Research 2019年第4期10卷 250-263页

作者： FU Yu LIAO Hong TIAN Xiang-Jun GAO Hao cai zhao-nan HAN Rui Climate Change Research Center Chinese Academy of SciencesBeijing100029China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing210044China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing10029China National Satellite Meteorological Center China Meteorological AdministrationBeijing100081China Key Laboratory of Middle Atmosphere and Global Environment Observation.Institute of Atmospheric Physics Chinese Academy of SciencesBeijing10029China

The study on how the variations in CO2 sources and sinks can affect the CO2 concentration over East Asia would be useful to provide information for policymaker concerning carbon emission *** this study,a nested-grid version of global chemical transport model(GEOS-Chem)is employed to assess the impacts of variations in meteorological parameters,terrestrial fluxes,fossil fuel emissions,and biomass burning on inter-annual variations of CO2 concentrations over East Asia in 2004—*** CO2 concentrations are compared with observations at 14 surface stations from the World Data Centre for Greenhouse Gases(WDCGG)and satellite-derived C 02 column density(XCO,)from the Gases Observing SATellite(GOSAT).The comparison shows that the simulated CO2 column density is generally higher than that of GOSAT by 1.33×10^6(annual mean point by point biases averaged over East Asia).The model reasonably captures the temporal variations of CO2 concentrations observed at the ground-based stations,but it is likely to underestimate the peaks-to-troughs amplitude of the seasonal cycle by 50%or *** simulated surface CO2 concentration in East Asia exhibits the largest inter-annual variation in December-January—February(DJF).The regional mean absolute deviation(MAD)values over East Asia are within(4.4—5.0)×10^-6 for all *** sensitivity simulations indicate that the inter-annual variations of surface CO2 concentrations are mainly driven by variations of meteorological parameters,and partly modulated by the inter-annual variations of terrestrial fluxes and fossil fuel emissions in local *** variations of the terrestrial fluxes and fossil fuel emissions may account for〜28%of the inter-annual variation of surface CO2 concentration in southern *** inter-annual variations of the peaks-to-troughs amplitude are dependent on variations of meteorological parameters,terrestrial fluxes and fossil fuel emissions in local *** influence of biomass burning emi

关键词： Carbon dioxide Inter-annual variation Terrestrial biosphere flux Fossil fuel emission

Real-data assimilation experiment with a joint data assimilation system: assimilating carbon dioxide mole fraction measurements from the Greenhouse gases Observing Satellite

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Atmospheric and Oceanic Science Letters 2016年第2期9卷 107-113页

作者： HAN Rui TIAN Xiang-Jun FU Yu cai zhao-nan Institute of Atmospheric Sciences Chengdu University of Information Technology/Plateau Atmosphere and Environment Key Laboratory of Sichuan Province International Center for Climate and Environment Sciences Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences Key Laboratory of Middle Atmosphere and Global Environment Observation Chinese Academy of Sciences

The performance of a joint data assimilation system（Tan-Tracker）,which is based on the PODEn4 Dvar assimilation method,in assimilating Greenhouse gases Observing SATellite（GOSAT） carbon dioxide（CO2） data,was *** 3D CO2 concentrations and CO2 surface fluxes（CFs） from2010 were simulated using a global chemistry transport model（GEOS-Chem）.TheTan-Tracker system used the simulated CO2 concentrations and fluxes as a background field and assimilated the GOSAT column average dry-air mole fraction of CO2（X（CO2）） data to optimize CO2 concentrations and CFs in the same assimilation *** simulated X（CO2）（X（CO2）Sim）） and assimilated X（CO2）（X（CO2）,TT） data retrieved at different satellite scan positions were compared with GOSAT-observed X（CO2）（X（CO2）,obs）*** average RMSE between the monthly X（CO2）,TT and X（CO2）,Obs data was significantly（30%） lower than the average RMSE between X（CO2）,Sim and X（CO2）,Obs）.Specifically,reductions in error were found for the positions of northern Africa（the Sahara）,the Indian peninsula,southern Africa,southern North America,and western *** difference between the correlation coefficients of the X（CO2）,Sim）and X（CO2）,Obs and those of the X（CO2）Π）,TT and X（CO2）,Obs was only *** general,the Tan-Tracker system performed very well after assimilating the GOSAT data.

关键词： Tan-Tracker GEOS-Chem GOSAT PODEn4DVar atmospheric CO2 concentration

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建筑工程项目异地缴税存在的难点和建议

当代会计 2021年第23期 181-183页

作者：赵彩男中国铁路上海局集团有限公司杭州房建公寓段

自2016年国家颁布并实施《关于全面推开营业税改征增值税试点的通知》(财税[2016]36号)以来,建筑业逐渐开始由缴纳营业税改为缴纳增值税。随着集团公司经济的不断发展、建筑企业增值税的推行以及越来越多异地建筑工程的施工,异地纳税问... 详细信息

自2016年国家颁布并实施《关于全面推开营业税改征增值税试点的通知》(财税[2016]36号)以来,建筑业逐渐开始由缴纳营业税改为缴纳增值税。随着集团公司经济的不断发展、建筑企业增值税的推行以及越来越多异地建筑工程的施工,异地纳税问题开始凸显出来。

关键词：建筑工程异地缴税难点建议

Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases

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Neural Regeneration Research 2025年第8期20卷 2373-2381页

作者： Lifang zhao Mingkai Zhang Qimeng Li Xuemin Wang Jie Lu Ying Han Yanning cai Department of Clinical Biobank Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Geriatric Medical Research Center BeijingChina Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Radiology and Nuclear Medicine Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics BeijingChina Key Laboratory of Neurodegenerative diseases Ministry of EducationBeijingChina School of Biomedical Engineering Hainan UniversityHaikouHainan ProvinceChina Center of Alzheimer’s Disease Beijing Institute for Brain DisordersBeijingChina National Clinical Research Center for Geriatric Diseases BeijingChina Institute of Biomedical Engineering Shenzhen Bay LaboratoryGaoke Innovation CenterShenzhenGuangdong ProvinceChina Department of Neurobiology Xuanwu HospitalCapital Medical UniversityBeijingChina

Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative ***,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°*** aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large *** samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline *** samples were stored at-80°C for up to 6 years before being used in this *** results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage ***,the level of total tau showed a negative correlation with sample storage ***,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage *** was not observed in individuals with cognitive ***,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage ***,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's ***,in cohort studies,it is important to consider the impact of storage time on the overall results.

关键词： Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein neurodegeneration neurofilament light chain plasma biomarkers single molecule array storage time tau

2008年冬季北京上空上对流层/下平流层臭氧的异常特征

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大气科学学报 2015年第6期38卷 796-803页

作者：赵倩刘毅管兆勇陆春晖蔡兆男南京信息工程大学气象灾害预报预警与评估协同创新中心江苏南京210044 中国科学院大气物理研究所中层大气与全球环境探测重点实验室北京100029 国家气候中心气候研究开放实验室北京100081

利用国产GPSO3臭氧探空系统观测的大气臭氧探空资料和NCEP再分析资料,结合对天气形势、大气环流背景、高空位涡变化及对流层顶高度扰动的分析,深入研究了2008年冬季北京地区10~14 km高度范围内持续出现的臭氧次峰值及大气臭氧含量异常... 详细信息

利用国产GPSO3臭氧探空系统观测的大气臭氧探空资料和NCEP再分析资料,结合对天气形势、大气环流背景、高空位涡变化及对流层顶高度扰动的分析,深入研究了2008年冬季北京地区10~14 km高度范围内持续出现的臭氧次峰值及大气臭氧含量异常现象。结果表明：在2008年我国南方雪灾这一特殊时期,引起臭氧垂直分布持续出现次峰值现象及臭氧含量异常的主要原因是平流层空气强烈下沉运动及其与对流层的交换作用,而引起这种下沉运动及平流层—对流层交换则是由于该阶段特殊的天气背景,乌拉尔阻塞高压长时间维持,贝加尔湖到巴尔喀什湖一带横槽稳定存在,里海以东切断低压长期维持,造成冷空气长时间、稳定地南下影响北京上空臭氧的垂直分布。加之副热带急流的出现,北京正处于其入口区左侧,其上空有强烈的辐合下沉运动,有利于平流层空气向下输送。此次臭氧次峰值及臭氧含量异常的现象很好地说明,在冷空气天气过程的影响下,北京地区上空的平流层空气运动及其与对流层的交换十分活跃。

关键词：臭氧探空臭氧次峰值平流层—对流层交换对流层顶折叠西风急流

应用MIPAS/ENVISAT卫星遥感资料研究平流层爆发性增温过程中大气化学成分变化特征

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遥感技术与应用 2008年第4期23卷 389-393,I0005页

作者：王海平刘毅蔡兆男中国科学院大气物理研究所北京100029

2002年12月～2003年1月北半球高纬地区平流层发生了一次爆发性增温过程（SSW），使该地区的动力、热力场和大气化学成分的分布发生剧烈变化。选取了搭栽在欧洲环境探测卫星EN—VISAT上的对地遥感观测仪器麦克耳逊干涉被动大气探测仪（MI... 详细信息

2002年12月～2003年1月北半球高纬地区平流层发生了一次爆发性增温过程（SSW），使该地区的动力、热力场和大气化学成分的分布发生剧烈变化。选取了搭栽在欧洲环境探测卫星EN—VISAT上的对地遥感观测仪器麦克耳逊干涉被动大气探测仪（MIPAS）的观测数据，首先利用臭氧探空资料和再分析气象资料对MIPAS观测的臭氧和温度廓线资料进行了对比验证；其次使用该资料对此次SSW过程进行了研究。对比结果显示，MIPAS资料与NCEP和臭氧探空资料都有较好的一致性。在这次平流层爆发性增温事件中，增温过程随时间向下传播影响到平流层下层。N2O和CH4的水平和垂直浓度分布与位涡反映的极涡始终都有很好的一致性。O3和H2O的浓度分布也受到极涡的限制，O3体积混合比随增温而增大，有极涡外的O3进入极涡。NO2并未受到极涡分布的严格限制，在极区维持低浓度区。HNO3浓度场在极区显示为极大值，但并不与极涡对应。

关键词： ENVISAT MIPAS 大气化学成分平流层爆发性增温

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng cai Shengjun Miao Yuan Li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

SensFL:Privacy-Preserving Vertical Federated Learning with Sensitive Regularization

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 385-404页

作者： Chongzhen Zhang Zhichen Liu Xiangrui Xu Fuqiang Hu Jiao Dai Baigen cai Wei Wang School of Automation and Intelligence Beijing Jiaotong UniversityBeijing100044China Shuohuang Railway Development Co. Ltd.National Energy GroupCangzhou062350China Beijing Key Laboratory of Security and Privacy in Intelligent Transportation School of Computer Science and TechnologyBeijing Jiaotong UniversityBeijing100044China

In the realm of Intelligent Railway Transportation Systems,effective multi-party collaboration is crucial due to concerns over privacy and data *** Federated Learning(VFL)has emerged as a promising approach to facilitate such collaboration,allowing diverse entities to collectively enhance machine learning models without the need to share sensitive training ***,existing works have highlighted VFL’s susceptibility to privacy inference attacks,where an honest but curious server could potentially reconstruct a client’s raw data from embeddings uploaded by the *** vulnerability poses a significant threat to VFL-based intelligent railway transportation *** this paper,we introduce SensFL,a novel privacy-enhancing method to against privacy inference attacks in ***,SensFL integrates regularization of the sensitivity of embeddings to the original data into the model training process,effectively limiting the information contained in shared *** reducing the sensitivity of embeddings to the original data,SensFL can effectively resist reverse privacy attacks and prevent the reconstruction of the original data from the *** experiments were conducted on four distinct datasets and three different models to demonstrate the efficacy of *** results show that SensFL can effectively mitigate privacy inference attacks while maintaining the accuracy of the primary learning *** results underscore SensFL’s potential to advance privacy protection technologies within VFL-based intelligent railway systems,addressing critical security concerns in collaborative learning environments.

关键词： Vertical federated learning privacy defenses