VLBI总体条纹拟合方法的应用及其效果

用总体条纹拟合求解各天线的延迟量和条纹率参数,可以提高与小天线相关基线的灵敏度。本文以射电致密陡谱源(CSS)3C43为例,就如何提高数据的信噪比,尽可能多地保留有效数据方面做了成功的尝试.从而十分有效地使用了总体条纹拟合方法.我们认为:对源结构的预知,配以恰当的处理技巧,能获取更多射电源结构信息,改善成图质量.     

DEPENDENCE BETWEEN FUSION TEMPERATURES AND CHEMICAL COMPONENTS OF A CERTAIN TYPE OF COAL USING CLASSICAL,NON-PARAMETRIC AND BOOTSTRAP TECHNIQUES

A statistical study of the dependence between various critical fusion temperatures of a certain kind ofcoal and its chemical components is carried out.As well as using classical dependence techniques(multiple,stepwise and PLS regression,principal components,canonical correlation,etc.)together withthe corresponding inference on the parameters of interest,non-parametric regression and bootstrapinference are also performed.     

RESOLUTION OF MULTICOMPONENT FLUORESCENT MIXTURES BY ANALYSIS OF THE EXCITATION-EMISSION-FREQUENCY ARRAY

Fluorescence lifetime provides a third independent dimension of information for the resolution of totalluminescence spectra of multicomponent mixtures.The incorporation of this parameter into theexcitation-emission matrix(EEM)by the phase modulation technique results in a three-dimensionalexcitation-emission-frequency array (EEFA).Multicomponent analysis based on the three-dimensionalEEFA brings a qualitative change for the resolved spectra,i.e.individual spectra can be uniquely resolved,which is impossible with any two-dimensional analysis.In this paper we present a method for analyzingthe EEFA.We show mathematically that with the three-dimensional analysis of the EEFA individualspectra and lifetimes can be obtained.Our algorithm is developed in mathematical detail and isdemonstrated by its application to a two-component mixture.     

超特大城市地形图数据建库分区设计

为提高超特大城市地形图数据库的操作效率,对超特大城市地形图数据库进行分区设计是非常必要的。提出一种基于地图要素的几何特征和空间尺度大小进行超特大城市地形图数据建库分区设计的方法,该方法顾及了城市的结构形状、地图要素的完整性以及各区地图要素数量均衡。给出北京市的数据建库分区设计实例。     

2000国家大地坐标系转换软件测评结果公示

正由国家测绘产品质量检验测试中心承担的国土资源空间数据2000国家大地坐标系转换软件测评工作于2018年1月31日公示测量结果,26款软件通过测评。2000国家大地坐标系转换软件测评工作是由国家测绘产品质量检验测试中心根据《国土资源部国家测绘地理信息局关于加快使用2000国     

国务院办公厅印发《科学数据管理办法》

正2018年3月17日,国务院办公厅印发《科学数据管理办法》,进一步加强和规范科学数据管理,保障科学数据安全,提高开放共享水平,更好地为国家科技创新、经济社会发展和国家安全提供支撑。《科学数据管理办法》对进一步提升我国科学数据工作水平,发挥国家财政投入产出效益,提高科     

A New Species of Tsuga (Pinaceae) based on Lignified Wood from the Late Miocene of Central Yunnan, China, and Its Paleoenvironmental Implications

A new species, Tsuga nanfengensis sp. nov. (Pinaceae), is described on the basis of lignified fossil wood from the late Miocene of the Xianfeng Basin, central Yunnan, southwestern China. Detailed observation of the fossil wood specimens show the following characteristics: distinct growth rings, absence of resin canals, uniseriate bordered pits in the radial wall of tracheids, ray tracheids and piceoid and cupressoid cross-field pits. These features indicate similarities to the wood of extant Tsuga canadensis, T. chinensis, and T. dumosa. According to the fossil record, Tsuga was present in Xundian County during the Miocene. Today Tsuga is drought intolerant, preferring wet conditions with no extant species growing naturally in Xundian County. The presence of Tsuga in the Miocene of Xundian County indicates a humid climate consistent with previous palaeoclimatic reconstructions showing a wetter and probably shorter dry season in the Miocene, relative to the present day. Therefore, the change in the local climate such as increasing aridity through the Miocene might explain the local extinction of Tsuga from central Yunnan.     

http://www.sciencedirect.com/science/article/pii/S1674987114001601

Data from a migmatised metapelite raft enclosed within charnockite provide quantitative constraints on the pressure-temperature-time[P-T-t) evolution of the Nagercoil Block at the southernmost tip of peninsular India.An inferred peak metamorphic assemblage of garnet,K-feldspar.sillimanite,plagioclase,magnetite,ilmenite,spinel and melt is consistent with peak metamorphic pressures of 6-8 kbar and temperatures in excess of 900℃.Subsequent growth of cordierite and biotite record high-temperature retrograde decompression to around 5 kbar and 800 C.SHRIMP U-Pb dating of magmatic zircon cores suggests that the sedimentary protoliths were in part derived from felsic igneous rocks with Palaeoproterozoic crystallisation ages.New growth of metamorphic zircon on the rims of detrital grains constrains the onset of melt crystallisation,and the minimum age of the metamorphic peak,to around560 Ma.The data suggest two stages of monazite growth.The first generation of REE-enriched monazite grew during partial melting along the prograde path at around 570 Ma via the incongruent breakdown of apatite.Relatively REE-depleted rims,which have a pronounced negative europium anomaly,grew during melt crystallisation along the retrograde path at around 535 Ma.Our data show the rocks remained at suprasolidus temperatures for at least 35 million years and probably much longer,supporting a long-lived high-grade metamorphic history.The metamorphic conditions,timing and duration of the implied clockwise P-T-t path are similar to that previously established for other regions in peninsular India during the Ediacaran to Cambrian assembly of that part of the Gondwanan supercontinent.