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Modified Observation Model in Tightly-Coupled INS/GPS Integration

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Journal of Beijing Institute of Technology 2017年第1期26卷 16-28页

作者： Guochao Fan Dan Song chengdong xu School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China

The conventional Kalman filter（CKF）is widely used in tightly-coupled INS/GPS integrated navigation *** linearization accuracy of the CKF observation model is one of the decisive factors of the estimation accuracy and therefore navigation ***,the conventional observation model（COM）used by the filter may be divergent,which would result into some terrible accuracies of INS/GPS integration navigation in some *** improve the navigation accuracy,the linearization accuracy of the COM still needs further *** deal with this issue,the observation model is modified with the linearization of the range and range rate equations in this *** with COM,the modified observation model（MOM）further considers the difference between the real user position and the position calculated by *** verify the advantages of this model,INS/GPS integrated navigation simulation experiments are conducted with the usage of COM and MOM *** to the simulation results,the positions（velocities）calculated using COM are divergent over time while the others using MOM are convergent,which demonstrates the higher linearization accuracy of MOM.

关键词： INS/GPS integration linearization modified observation model (MOM) conventionalobservation model (COM)

Evolution of Hydrogen Storage Alloys Prepared by Special Methods

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Journal of Rare Earths 2004年第Z1期22卷 222-227页

作者： Guo Hong Zhang Ximin Jing Hai Li chengdong xu Jun National Engineering and Technology Research Center for Non-Ferrous Metals Composites General Research Institute for Non-Ferrous Metals Beijing 100088 China National Engineering and Technology Research Center for Non-Ferrous Metals Composites General Research Institute for Non-Ferrous Metals Beijing 100088 China National Engineering and Technology Research Center for Non-Ferrous Metals Composites General Research Institute for Non-Ferrous Metals Beijing 100088 China National Engineering and Technology Research Center for Non-Ferrous Metals Composites General Research Institute for Non-Ferrous Metals Beijing 100088 China National Engineering and Technology Research Center for Non-Ferrous Metals Composites General Research Institute for Non-Ferrous Metals Beijing 100088 China

Microstructure characteristics and electrochemical properties of hydrogen storage alloys prepared by gas atomization, melt spinning and strip casting respectively were *** advantages, disadvantages and research development of the above methods for preparing hydrogen storage alloys were *** strip casting is a new special means for preparing AB5 rare earth hydrogen storage alloys of high performance and low cost, and the study of the strip casting for preparing hydrogen storage alloys is presented specially.

关键词： hydrogen storage alloys gas atomization melt spinning strip casting rare earths

Built-in electric field influence on impurity-free vacancy disordering of InGaAs/InP quantum well structure

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Chinese Science Bulletin 2010年第14期55卷 1363-1366页

作者： AN YuPeng MEI Ting TENG JingHua xu chengdong WANG YiDing State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130012 China School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798 Singapore Institute of Materials Research and Engineering 3 Research Link Singapore 117602 Singapore

Built-in electric field may enhance or retard the impurity-free vacancy disordering (IFVD) during rapid thermal annealing (RTP) by imposing a drift on charged point defects. Built-in electric field is at the interface between dielectric layer and top layer of the structure. Subsequent rapid thermal annealing leads to different intermixing results due to different field directions on InP cap layers in different doping types. Experimental results also show different influences of the built-in field on the two sublattices largely due to different charge numbers of point defects.

关键词：内建电场井身结构 InGaAs 内置杂质无序 InP 快速热退火

Natural and Socioeconomic Factors and Their Interactive Effects on House Collapse Caused by Typhoon Mangkhut

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International Journal of Disaster Risk Science 2021年第1期12卷 121-130页

作者： Xiangxue Zhang Juan Nie Changxiu Cheng chengdong xu Ling Zhou Shi Shen Yuan Pei Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China National Disaster Reduction Center of China Ministry of Emergency ManagementBeijing 100124China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China National Tibetan Plateau Data Center Beijing 100101China

Typhoons are an environmental threat that mainly affects coastal regions *** interactive effects of natural and socioeconomic factors on the losses caused by typhoon disasters need further *** this study,GeoDetector was used to quantify the determinant powers of natural and socioeconomic factors and their interactive effects on the rate of house collapse in Guangdong and Guangxi Provinces of southeast China caused by Typhoon Mangkhut in *** further identify the dominant factors that influenced the disaster *** local indicators of spatial association method was then introduced to explain the spatial heterogeneity of the disaster losses under the influence of the dominant *** results indicate that both natural and socioeconomic factors significantly affected the house collapse *** maximum precipitation was the dominant factor,with a q value of 0.21,followed by slope and elevation,with q values of 0.17 and 0.13,*** density and per capita gross domestic product had q values of 0.15 and0.13,*** all of the interactive effects of the influencing factors,the interactive effect of elevation and the ratio of brick-wood houses had the greatest influence(q=0.63)on the house collapse *** results can contribute to the formulation of more specific safety and property protection policies.

关键词： China Coastal regions GeoDetector House collapse rate Interactive effects Typhoon Mangkhut

Associations Between Air Temperature and Daily Varicella Cases—Jinan City,Shandong Province,China,2019–2021

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China CDC weekly 2024年第2期6卷 36-39,I0008,I0009页

作者： Guijie Luan Yuehua Hu Meng Chen Meiying You chengdong xu Dapeng Yin Jianjun Liu Hongyan Yao Chinese Center for Disease Control and Prevention BeijingChina Institute for Immunization management Shandong Center forDisease Control and PreventionJinan CityShandong ProvinceChina State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina Hainan Provincial Center for Disease Control and Prevention Haikou CityHainan ProvinceChina.

What is already known about this topic?The impact of air temperature on varicella has been studied,but there is limited research exploring its effect on varicella by gender and age *** is added by this report?We conducted a time series analysis to examine the differential effects of air temperature on varicella infection across different demographic *** findings indicate that lower temperatures have a more pronounced influence on varicella incidence among males and children compared to females and *** are the implications for public health practice?These findings can assist in identifying populations that are vulnerable to temperature-related varicella and in guiding the implementation of effective measures for varicella control.

关键词： finding measures Shandong

Burden of Vaginitis Among Chinese Women Aged 18-74 Years——Five Provinces, China, 2023

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China CDC weekly 2024年第49期6卷 1299-1305页

作者： Zixuan Fan Chenyang Pei Jing Ma chengdong xu Zhenbo Wang Yuanli Liu Yuehua Hu School of Health Policy and Management Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina Institute for Hospital Management of Tsinghua University Shenzhen CityGuangdong ProvinceChina State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina Office of Epidemiology Chinese Center for Disease Control and PreventionBeijingChina

Summary What is already known about this topic?Vaginitis is a prevalent and treatable gynecological condition in women that is associated with adverse reproductive outcomes,human papillomavirus(HPV)infection,and elevated human immunodeficiency virus(HIV)transmission *** is added by this report?This study identifies elevated infection risks among women aged 35–54 years,those with three or more pregnancies,and individuals who smoke or consume alcohol,with notably higher prevalence rates in Hubei and Yunnan *** findings demonstrate that awareness of cervical cancer screening serves as a protective factor,while emphasizing screening’s crucial role in early vaginitis detection.

关键词： elevated protective smoke

Discussion on Preparation and Application of BiOIO_(3)-based Composite Materials

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Agricultural Biotechnology 2020年第6期9卷 104-107,135页

作者： chengdong xu Yushan WAN School of Environmental&Safety Engineering Changzhou UniversityChangzhou 213164China

BiOIO3 is a layered semiconductor photocatalyst,which has good chemical properties and has attracted wide attention from researchers because of its unique ***,pure BiOIO3 has defects such as insufficient response to visible light and easy recombination of photogenerated ***,in recent years,scholars have tried to modify BiOIO3 to expand its light absorption range,reduce the recombination of photogenerated electron-hole pairs and reduce its limitations,thereby improving its visible light catalytic *** researches focus on the improvement of the catalytic activity of photocatalytic materials from morphology control,precious metal deposition,ion doping and construction of heterojunctions.

关键词： BiOIO3 Photocatalysis Composite material Degradation

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基于策略支持的信息安全评估系统设计与实现

计算机工程 2006年第2期32卷 144-146,205页

作者：聂伟许承东北京理工大学二院北京100081

提出了一个基于策略支持的信息系统安全评估模型,描述了一个基于该模型系统的结构和实现机制,并应用模糊集和有向图理论对扫描数据进行分析。基于该设计思想的安全评估软件能够适应大型复杂信息网络,并能方便地与其他安全产品整合。

关键词：计算机网络关联分析安全评估漏洞扫描

Spatial Dynamics of Chickenpox Outbreaks in Rapidly Developing Regions:Implications for Global Public Health

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Biomedical and Environmental Sciences 2024年第7期37卷 687-697页

作者： Li Wang Miaomiao Wang chengdong xu Peihan Wang Meiying You Zihan Li Xinmei Chen Xinyu Liu xudong Li Yuanyuan Wang Yuehua Hu Dapeng Yin College of Geography and Environmental Science Henan UniversityKaifeng 475001HenanChina State Key Laboratory of Resources and Environmental Information System Institute of Geographic Science and Natural Resource ResearchChinese Academy of SciencesBeijing 100101BeijingChina Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Henan University) Ministry of EducationKaifeng 475001HenanChina Office of Epidemiology Chinese Center for Disease Control and PreventionBeijing 102206BeijingChina University of Chinese Academy of Sciences(UCAS) Beijing 100101BeijingChina Weifang Municipal Center for Disease Control and Prevention Weifang 261061ShandongChina Hainan Center for Disease Control and Prevention Haikou 570203HainanChina

Objective The occurrence of chickenpox in rapidly developing areas poses substantial seasonal risk to ***,certain factors influencing local chickenpox outbreaks have not been ***,we examined the relationship between spatial clustering,heterogeneity of chickenpox outbreaks,and socioeconomic factors in Southern *** We assessed chickenpox outbreak data from Southern China between 2006 and 2021,comprising both relatively fast-growing parts and slower sub-regions,and provides a representative sample of many developing *** analyzed the spatial clustering attributes associated with chickenpox outbreaks using Moran’s I and local indicators of spatial association and quantified their socioeconomic determinants using Geodetector q *** There were significant spatial heterogeneity in the risk of chickenpox outbreaks,with strong correlations between chickenpox risk and various factors,particularly demographics and living ***,interactive effects among specific are factors,such as population density and per capita residential building area,percentage of households with toilets,percentage of rental housing,exhibited q statistics of 0.28,0.25,and 0.24,*** This study provides valuable insights into the spatial dynamics of chickenpox outbreaks in rapidly developing regions,revealing the socioeconomic factors affecting disease *** implications extend the formulation of effective public health strategies and interventions to prevent and control chickenpox outbreaks in similar global contexts.

关键词： Chickenpox Spatial dynamics Socioeconomic factors