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Major Trends in Population Growth Around the World

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China CDC weekly 2021年第28期3卷 604-613页

作者： danan Gu Kirill Andreev Matthew E.Dupre United Nations Population Division New YorkUSA Department of Population Health Sciences&Department of Sociology Duke UniversityNorth CarolinaUSA

Summary The world’s population continues to grow,albeit at a slower *** decelerating growth is mainly attributable to fertility declines in a growing number of ***,there are substantial variations in the future trends of populations across regions and countries,with sub-Saharan African countries being projected to have most of the increase.

关键词： Population Growth fertility

Seasonal vertical crustal mo-tions in China detected by GPS

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Chinese Science Bulletin 2002年第21期47卷 1772-1780,1849页

作者： ZHANG Feipeng DONG danan CHENG Zongyi CHENG Mingkang HUANG Cheng Shanghai Astronomical Observatory National Astronomical ObservatoryUnited Center for Astro-geodynamics ResearchChinese Academy of SciencesShanghai 200030China Jet Propulsion Laboratory California Institute of Technology4800 Oak Grove Dr.Pasadena78759 CaliforniaUSA Center for Space Research University of Texas at Austin91109 AustinUSA

By analyzing daily continuous data of Chinese Global Positioning System (GPS) fiducial network with 25 sites from 1999 to 2001, seasonal altitude variations with amplitude of 3-10 mm are detected. Most part of the variations can be explained by the seasonal vertical crustal movements caused by atmospheric pressure variation and mass loading redistribution of non-tidal ocean loading, snow, and soil moisture. Nevertheless, there exists a systematic discrepancy between GPS deduced result and the counterpart predicted by combining various geophysical sources. Much longer time series of GPS site coordinates and further studies are still needed to give out a reasonable interpretation for this discrepancy.

关键词： crustal movement seasonal altitude variation GPS mass loading redistribution.

Remaining Useful Life Prediction for a Multi-stack Solid Oxide Fuel Cell System with Degradation Interactions

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1207-1214页

作者： Xiaojuan Wu Liangfei Xu Yang Huang danan Yang Junhao Wang Houjun Wang Xi Li School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 610054China State Key Lab of Automotive Safety and Energy School of Vehicle and MobilityTsinghua UniversityBeijing 100084China School of Artificial Intelligencei and Automation Key Laboratory of Image Processing and Intelligent Control of Education MinistryHuazhong University of Science and TechnologyWuhan 430074China

Due to the constraints of manufacturing and materials,high-power plants cannot rely on only one solid oxide fuel cell stack.A multi-stack system is a solution for a highpower system,which consists of multiple fuel cell stacks.A short lifetime is one of the main challenges for the fuel cell before largescale commercial applications,and prognostic is an important method to improve the reliability of fuel *** from the traditional prognostic approaches applied to single-stack fuel cell systems,the key problem in multi-stack prediction is how to solve the correlation of multi-stack degradation,which can directly affect the accuracy of *** response to this difficulty,a standard Brownian motion is added to the traditional Wiener process to model the degradation of each stack,and then the probability density function of the remaining useful life(RUL)of each stack is ***,a Copula function is adopted to reflect the dependence between life distributions,so as to obtain the remaining useful life for the whole multi-stack system.1 The simulation results show that compared with the traditional prediction model,the proposed approach has a higher prediction accuracy for multi-stack fuel cell systems.

关键词： Degradation interaction multi-stack remaining useful life(RUL) solid oxide fuel cell(SOFC)

Multi-antenna synchronized global navigation satellite system receiver and its advantages in high-precision positioning applications

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Frontiers of Earth Science 2016年第4期10卷 772-783页

作者： danan DONG Wen CHEN Miaomiao CAI Feng ZHOU Minghua WANG Chao YU Zhengqi ZHENG Yuanfei WANG Engineering Center of SHMEC for Space Information and GNSS East China Normal University Shanghai 200241 China Shanghai Key Laboratory of Multidimensional Information Processing East China Normal University Shanghai 200241 China Key Laboratory of Geographic Information Science Ministry of Education East China Normal University Shanghai 200241 China College of Surveying and Geo-informatics Tongji University Shanghai 200092 China

The multi-antenna synchronized global navi- gation satellite system receiver is a high precision, low cost, and widely used emerging receiver. Using this type of receiver, the satellite and receiver clock errors can be eliminated simultaneously by forming between antenna single-differences, which is equivalent to the conventional double-difference model. However, current multi-antenna synchronized global navigation satellite system receiver products have not fully realized their potential to achieve better accuracy, efficiency, and broader applications. This paper introduces the conceptual design and derivable products of multi-antenna synchronized global navigation satellite system receivers involving the aspects of attitude determination, multipath effect mitigation, phase center variation correction, and ground-based carrier phase wind- up calibration. Through case studies, the advantages of multi-antenna synchronized global navigation satellite system receivers in high-precision positioning applications are demonstrated.

关键词： multi-antenna synchronized global navigationsatellite system receiver high-precision positioning attitudedetermination multipath effect mitigation phase centervariation correction ground-based carrier phase wind-upcalibration

The development of library science in China in an international perspective

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Journal of Library Science in China 2019年 28-39页

作者： CHENG Huanwen LIU Jiaqin ZHAO danan School of Information Management Sun Yat-Sen UniversityGuangzhou 510006China

This article describes the development of the internationalization of Chinese library science and the Chinization of international library science from an international perspective based on the historical research *** development of Chinese library science in the past one hundred years is mainly embodied in the Chinization of international standards,technologies and *** article suggests that the Chinese library science research should make the world hear its voice,spread Chinese ideas,promote innovations in Chinese library community and help to bolster the development of global librarianship.

关键词： Library science in China International perspective Academic ideology Library discipline

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老年人健康变动趋势和预测方法国际研究动态

中国人口科学 2005年第3期 81-86页

作者：顾大男美国杜克大学公共政策系

文章就当前国际老年学界对老年人健康特别是失能状况变动趋势的研究动态进行了回顾。其初步结论是自20世纪90年代以来,许多国家的老年人失能比例下降,但下降的原因尚不清楚。许多学者建议在以后的调查设计中应搜集一些影响功能状况及针... 详细信息

文章就当前国际老年学界对老年人健康特别是失能状况变动趋势的研究动态进行了回顾。其初步结论是自20世纪90年代以来,许多国家的老年人失能比例下降,但下降的原因尚不清楚。许多学者建议在以后的调查设计中应搜集一些影响功能状况及针对性治疗等方面的辅助信息。文章还回顾了目前国际老年学界预测未来老年人健康状况的多种方法,结果显示目前的预测虽然较以往有了很大的拓展但仍存在不足。

关键词：研究动态变动趋势老年人国际预测方法 20世纪90年代以来辅助信息调查设计健康状况老年学回顾文章下降

Discussion on the Characteristics and Symptom Classification of COVID-19 in Chinese Medicine

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Journal of Clinical and Nursing Research 2021年第4期5卷 128-132页

作者： Na Yang Yun Li Wangbo Cao danan Yang Dezhou People's Hospital Dezhou 253000Shandong ProvinceChina Dezhou Hospital of Traditional Chinese Medicine Dezhou 253000Shandong ProvinceChina

Covid-19(Novel coronavirus pneumonia,NCP)was characterized by fever,dry cough,fatigue,greasy tongue coating and pulsating *** to the literature,with those four symptoms,examination and identification,it is believed that NCP belongs to the category of "pandemic" in Chinese *** main infection is dampness,infection location in triple energizer,the basic pathogenesis is characterized by "dampness,phlegm,blood stasis heat,toxin and deficiency."According to the law of blood transfer of symptom differentiation of triple energizer and weiqi-yingxue the treatment is divided into stages,such as early stage,middle stage,severe stage and recovery *** of the patients were early stage and middle stage,which were the direct transmission of the disease.A small number of patients had the reverse transmission of pericardium and the internal and external *** main method of treatment is to remove infection,remove dampness and *** addition,to grasp the treatment of early stage and middle stage patients,helps to stop the disease from developing,and it is the key to reduce the criticality of the disease,as well as reduce the mortality.

关键词： COVID-19 Damp virus pandemic Triple energizer Symptom classification and treatment Dezhou

Neuroplastin 65 mediates formation of Aβ deposits and neuroinflammation in AD mice

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Neuroplastin 65 mediates formation of Aβ deposits and neuro...

中国解剖学会2021年年会

作者： Wu danan Liu Lifen Zheng Ximing Li nana Yuan Qionglan Tongji University School of Medicine

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that causes impaired memory and *** 65 (NP65),specifically expressed in the synaptic membranes of brain,has been reported to mediate cognitive ***,...

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设立广深铁路客户服务中心的探索与思考

中国铁路 2010年第1期 61-63页

作者：刘达南广深铁路股份有限公司综合管理部助理经济师广东深圳518001

为满足社会公众对铁路运输服务多层次、全方位的需求,建议设立广深铁路客户服务中心,创新旅客贷主查询和咨询服务方式,将传统站车现场服务与客服中心有机结合,实现服务水平和企业"软"实力的全面提升。

关键词：铁路运输客户服务广深铁路客服中心