丘陵地貌区高程内插适宜方法选择——以长春净月潭为例

对不同的地貌区进行空间内插时选择的适宜方法不同,以典型丘陵地貌区长春市净月潭地区的高程为研究对象,用ArcGIS 9.2分别作反距离权重法、最近邻点法、趋势面分析和克里金法做高程内插。应用交叉检验方法对其内插的精度作出分析,检验其科学性和可靠性,得出反距离权重法、最近邻点法、趋势面法、样条函数法和克里金法高程内插的不同精度,并对各种方法的适用性进行讨论。结果表明最近邻点法精度最高,以下依次为普通克里金插值法、样条函数、反距离权重法、趋势面法。为类似于净月潭地区的丘陵地貌区高程内插提供选择参考。     

中国土壤湿度的时空变化特征

基于中国155个农业气象观测站1981-2010年逐旬土壤湿度资料,分析了全国和12个气候区域0~50 cm逐层的土壤湿度时空分布规律,采用趋势分析和Cramér-von Mises（CVM）方法探究了土壤湿度的变化趋势及突变性。结果表明：西南、江淮、东北、江南、江汉、黄淮和华南地区各层土壤湿度均高于全国平均值,内蒙古地区最低;随着深度增加,西南地区土壤湿度增加最明显,仅青藏高原地区土壤湿度减小。不同区域0~50 cm各层土壤湿度年变化和季节变化差异明显,并具有阶段性特征,大部地区深层土壤湿度高于浅层;总体上,新疆、华南、华北、青藏高原、东北、黄淮地区1981-2010年土壤湿度减小趋势显著,其中新疆地区减小最为明显。除江淮地区外,各区域土壤湿度均存在较为明显的年际差异,突变时段主要集中在20世纪80年代后期至90年代初期、90年代后期两个时间段。     

Analysis of digital elevation data for palaeosurfaces in south-western Sweden

A 3873-km² large rectangular area of the Precambrian basement in south-western Sweden has been investigated regarding gross morphology of palaeosurfaces. GIS and digital elevation data were used to construct maps of relative and absolute relief and E–W trending height profiles. Three different palaeosurfaces were recognised and delimited; the very even sub-Cambrian peneplain in the east at an intermediate altitudinal position, an uplifted and broken part of the sub-Cambrian peneplain in the centre at the highest present elevation, and in the western coastal areas a joint-aligned valley landscape with high relative relief, probably an exhumed Mesozoic etch-surface. Phanerozoic faulting has dissected the different palaeosurfaces into tectonic blocks, which are shown from trend surface analysis to be tilted in different directions and to different degrees, characteristic and decisive for the morphological development.     

A New Method of Significance Testing for Correlation-Coefficient Fields and Its Application

Correlation-coefficient fields are widely used in short-term climate prediction research. The most frequently used significance test method for the correlation-coefficient field was proposed by Livezey, in which the number of significantcorrelation lattice(station) points on the correlation coherence map is used as the statistic. However, the method is based on two assumptions:(1) the spatial distribution of the lattice(station) points is uniform;and(2) there is no correlation between the physical quantities in the correlation-coefficient field. However, in reality, the above two assumptions are not valid.Therefore, we designed a more reasonable method for significance testing of the correlation-coefficient field. Specifically, a new statistic, the significant-correlation area, is introduced to eliminate the inhomogeneity of the grid(station)-point distribution, and an empirical Monte Carlo method is employed to eliminate the spatial correlation of the matrix.Subsequently, the new significance test was used for simultaneous correlation-coefficient fields between intensities of the atmospheric activity center in the Northern Hemisphere and temperature/precipitation in China. The results show that the new method is more reasonable than the Livezey method.     

两种显著性检验方法在海洋大数据序列主成分分析中的应用

介绍海洋大数据序列主成分分析的两种显著性检验方法,采用该两种方法可以辨别具有真实意义的主成分模与代表随机噪声信号的模态。此二法均能很好地应用于大数据序列主成分模的显著性检验。在进行海洋大数据序列时-空变化主成分分析中,为尽可能减少或避免数据中随机噪声的影响,建议对主成分模进行显著性检验。     

Full scale decay test of a tanker: field data and theoretical analysis

This paper presents results from a full scale decay test made with a tanker in a relatively protected area in the Brazilian coast. In at least two tests the environmental loads (wind, waves and current) were very small and the time history of the surge motion was well behaved, making it possible to check some proposed models for the damping in the hull and mooring lines. Field data seem to confirm that the damping is indeed of the fluid viscosity type and the theoretical models are able to recover roughly 75% of the observed damping, the energy dissipation in the mooring lines being, by far, the major contribution. The remaining 25% are likely due to non modeled effects, such as the environment influence, which although small and not measured certainly exists, and to the friction between the mooring lines and the seabed.     

05106型海洋风传感器简介

本文介绍了美国Ｒ．Ｍ．ＹＯＵＮＧ公司的新产品－０５１０６型海洋风传感器,并简单地分析了Ｒ．Ｍ．ＹＯＵＮＧ公司在该风传感器中采用的关键技术。     

国内外海洋资料浮标技术现状与发展

海洋资料浮标是长期连续进行海洋监测的主要手段之一。本文简单介绍了国内外海洋资料浮标技术的现状与发展及浮标在我国海洋监测中的应用情况,提出了我国资料浮标技术的研究与发展设想。     

承压水沿煤层底板递进导升突水机理的物理法研究

完整底板和非完整底板的注水试验发现底板深处的耗水早于浅部,显示底板的破裂发生在采前,相似材料模拟具一定导升高度的底板在采动中的变化揭示了同样的规律。底板的原位应力测试发现承压水在采前出现了向上入侵的现象,二次应力给导升的发展提供了条件,递进导升是突水机理之一。     

对中国地球物理学发展的思考--兼论中国科学院地球物理研究所在地球科学中心建设中的地位与作用

无论是从对地球物理性质的基本认识,还是从国民经济经济发展的需要看,地球物理学都应得到重视和发展。在总结我国地球物理工作的基础上,讨论了地球物理学尤其是固体地球物理学的趋势,如学科发展问题、重大科学问题及观测手段问题等。在此基础上,对地球物理研究所在固体地球科学中心中的地位及作用进行了分析,它就是以基础民为国民经济经济服务及为国家决策咨询相并重。另外,对建立地球科学中心的模式进行了初步探讨。