The Common Principal Component Analyses of Multi-RCMs          下载免费PDF全文

FENG Jin-Ming  WANG Yong-Li  FU Cong-Bin 《大气和海洋科学快报》2013,6(1):14-20

Based on a 10-year simulation of six Regional Climate Models(RCMs) in phase II of the Regional Climate Model Inter-Comparison Project(RMIP) for Asia,the multivariate statistical method of common principal components(CPCs) is used to analyze and compare the spatiotemporal characteristics of temperature and precipitation simulated by multi-RCMs over China,including the mean climate states and their seasonal transition,the spatial distribution of interannual variability,and the interannual variation.CPC is an effective statistical tool for analyzing the results of different models.Compared with traditional statistical methods,CPC analyses provide a more complete statistical picture for observation and simulation results.The results of CPC analyses show that the climatological means and the characteristics of seasonal transition over China can be accurately simulated by RCMs.However,large biases exist in the interannual variation in certain years or for individual models.  相似文献   

我国东北区域参考框架的空间关系时空特性研究     

蒋光伟  王斌  陈雄川  田晓静  王盼龙 《大地测量与地球动力学》2021,41(6):606-611

以东北地区2005~2018年近14 a的中国地壳运动观测网络数据为基础,采用三角划分方法构建相邻区域的基线时间序列,从频谱特征、残余共模误差、空间相对运动规律3个方面进行时空特征分析。结果表明,基线各分量的周期性影响主要以年周期和半年周期为主;基线之间的残余共模误差在平面方向的影响约为1.14 mm,垂直方向的影响最大为3.17 mm;平均随机影响在东西方向最大;基线水平分量在空间尺度上逐年缩短,以北东方向的基线为主,在南北分量尤为明显,且在近海和内陆地区都有较明显的缩短趋势。  相似文献   

城乡之间：当代农村家庭的空间生产何以可能？     

陈景亮  潘小焮  张冬 《热带地理》2022,42(11):1878-1889

从空间生产理论出发,以W村为研究个案,采用参与式观察和深度访谈方法,基于“空间变换”与“农村家庭”的交叠过程,探讨农村家庭的发展。研究发现：当代农村家庭生计的空间穿梭、家庭居住的空间镶嵌,以及家庭生活方式的空间效仿等实践是农村家庭“离乡不离农”的“城乡之间”发展新方式。在空间表象为农村家庭与城市互融互嵌、不分物质、不分精神的共同富裕需求。但城乡现实情境的差异,农村家庭仍表现出对农业生产以及农村生活的不自信,呈现出农村社会人伦与位育日渐式微的表征性空间。在全面推进乡村振兴以及共同富裕的进程中,应建设“零价差”的社会政策空间,再塑村落自信的农村家庭发展外部空间,重构个体自主的农村家庭发展内部空间,据此建构回应家庭发展内生需求的城乡二元物理空间及其一元社会服务空间。  相似文献   

海洋生态产品政策的经济效应: 提升供给效率与实现共同富裕——基于中国沿海省份的数据分析     

贺义雄  阮佳航  谢素美  徐敏  陈翔宇  刘佰琼 《海洋科学》2022,46(12):74-87

为探讨海洋生态产品政策工具的经济效应, 尤其是对提升其供给效率与实现共同富裕的叠加影响, 本文在设计理论分析框架的基础上, 基于中国沿海省、自治区、直辖市2009—2019年的数据分析, 利用计量方法研究了共同富裕、海洋生态产品供给效率、海洋生态产品政策之间的作用机制和影响机理。结果显示: 海洋生态产品政策可显著提升中国海洋生态产品供给效率, 促进共同富裕; 海洋生态产品政策在各区域的经济效应显著度呈东海-环渤海-南海依次递减的情况; 产业结构、人均受教育年限、人口总数、人均存款、人均贷款、人均财政支出、人均财政收入、少数民族地区情况等因素均会对海洋生态产品政策的经济效应产生影响。提出建议: 明确优化提升海洋生态产品供给效率和促进实现共同富裕的政策目标; 研究有利于优化提升海洋生态产品供给效率和促进实现共同富裕的政策工具; 做好区域海洋生态产品政策的构建与完善工作。  相似文献   

顾及共模误差的四川连续GPS基准站坐标时间序列噪声分析     

刘宗强  党亚民  杨强  张光茹  王健  韩德强 《大地测量与地球动力学》2018,38(5):510-515

使用GAMIT/GLOBK软件处理四川省内23个连续GPS基准站2010～2015年数据，获取各测站的坐标时间序列，然后利用堆栈法对其进行空间滤波以剔除共模误差，通过谱指数计算和最大似然估计法（MLE）对滤波后的GPS站坐标时间序列进行噪声分析。结果表明，四川连续GPS基准站坐标时间序列N、U方向最优噪声模型为WN+FN，E方向最优噪声模型为WN+FN+RWN；空间滤波可以降低闪烁噪声，同时使一些测站显现出随机漫步噪声；根据GPS站坐标时间序列估计基准站速度时，应当顾及有色噪声的影响。  相似文献   

ANALYSIS OF HABITAT PATTERN CHANGE OF RED—CROWNED CRANES IN THE LIAOHE DELTA USING SPATIAL DIVERSITY INDEX     

WANG Ling    LI Xiu-zhen  HU Yuan-man  GUO Du-fa   《中国地理科学(英文版)》2003,13(2):164-170

1INTRODUCTIONThewildlifehabitatlossandfragmentationhavebeenlinkeddirectlytointensivehumandisturbance.Manyecologistshavefocusedonanalysisofwildlifehabitatpatternchangeandconservationofsuitablehabitat.Ingeneral,landscapepatterniscloselylinkedtoecologi-calfunction,andnumerouspatternindiceshavebeencitedtodescribehabitatpatternandsuitability(FRANKLINandFORMAN,1987;HANSENandURBAN,1992;SCHUMAKER,1996;RIITTERSetal.,1997;PEARSONetal.,1999;CHENetal.,1999).WiththeapplicationofG…  相似文献   

CCA Inferred Environmental Implications of Common Ostracods on the Qinghai-Tibetan Plateau     

SONG Gao  WANG Hailei  ZHENG Mianping 《《地质学报》英文版》2015,89(2):585-597

103 surface sediment samples in 71 water bodies,such as lakes with different salinity,swamps,shallow puddles and rivers on the Qinghai-Tibetan Plateau(QTP),were collected to study the ecological distribution of living ostracods and their environmental implications. Total of 12 genus and 45 species living ostracods are identified. According to the frequencies and abundance of ostracods occurrence,Limnocythere dubiosa,Limnocytherellina kunlunensis,Ilyocypris bradyi,Candona candida,Eucypris rischtanica and Leucocythere dilatata are the common species on the QTP,with occurrence frequency of more than 8 and abundance of more than 570 in the 71 water bodies. Among them,L. dubiosa,occurring in 28 water bodies with 2177 shells,is the most widely distributed ostracod in this research. Canonical Correspondence Analysis(CCA) indicates high correlation between species and environmental variables,suggesting that the occurrence of species is strongly related to the changes in ecological conditions of habitats. Among eight environmental factors,salinity and p H value are the most affective variables that influence the species occurrence. L. kunlunensis is positively correlated with salinity while E. rischtanica is negatively correlated with salinity. C. candida has a positive correlation with salinity,as does I. bradyi although there is not such a strong correlation. L. dubiosa displays a positive correlation with p H value. Consequently,we discuss the environmental implications of the common living ostracods on the QTP based on the CCA as well as the distribution of ostracod species in different salinity and p H values water. L. dubiosa,L. kunlunensis and E. rischtanica are euryhaline species,among which,L. dubiosa is the most adaptable species on the QTP with large occurrence in sundry salinity water and the most widely adaptive range for p H values. L. kunlunensis prefers to saline water while E. rischtanica prefers to fresh water. Both L. kunlunensis and E. rischtanica can live in water from faintly acid to alkaline,in contrast,L. dubiosa only appears in neutral and alkaline water bodies. I. bradyi only occurs in fresh water and oligohaline water with a large p H tolerance range tolerance range from weakly acidic water to alkaline water weakly acidic water to alkaline water. C. Candida lives in freshwater,with p H value above eight. The six common species reach maximum abundance in alkaline water(p H 8-10) except for Ilyocypris bradyi.  相似文献   

Methods for ultimate limit state assessment of ships and ship-shaped offshore structures: Part II stiffened panels     

Jeom Kee Paik  Bong Ju Kim  Jung Kwan Seo 《Ocean Engineering》2008,35(2):271-280

The present paper is Part II of a series of three papers on methods useful for the ultimate limit state assessment of ships and ship-shaped offshore structures. In contrast to Part I [Paik et al., 2007a. Methods for ultimate limit state assessment of ships and ship-shaped offshore structures: Part I unstiffened plates, Ocean Engineering, doi:10.1016/j.oceaneng.2007.08.004] that deals with unstiffened plates, the present paper (Part II) is focused on methods for the ultimate limit state assessment of stiffened plate structures under combined biaxial compression and lateral pressure actions. The object structure is the bottom part of an AFRAMAX-class hypothetical double-hull oil tanker structure designed by IACS common structural rules (CSR) method, that is the same ship studied in Part I. Three candidate methods, namely ANSYS nonlinear finite element method, DNV PULS method, and ALPS/ULSAP method, are employed for the present study. The results and insights developed from the present study are summarized in terms of ultimate strength characteristics of bottom-stiffened plate structures.  相似文献   

三维激光扫描点云数据压缩方法   总被引：5，自引：0，他引：5  

黄承亮  吴侃  向娟 《测绘科学》2009,34(2)

三维激光扫描获得的点云数据,其数据量比较大,通过分析三维激光扫描数据的特点,本文提出了两个数据压缩方法,分别为区域重心数据压缩法和基于三维TIN数据的共顶点数据压缩法,介绍了两种数据压缩方法的原理和实现过程,并对区域重心数据压缩法进行实例分析,得出了压缩结果。  相似文献   

采用双重投影法的椭球面日晷投影     

丁佳波 《武汉大学学报(信息科学版)》2000,25(2)

研究了从地球椭球面描写到海图平面的采用双重投影法的日晷投影方程式 ,并阐明了椭球面日晷投影的 3个重要特性及其应用  相似文献