Equal arc ratio projection and a new spherical triangle quadtree model

A projection family, named Equal Arc Ratio Projection (EARP), is proposed in this paper, which has two kinds of geometric cases. Coordinates in the projections are determined by the ratios between four special arcs. The projection for spherical octahedron is derived, which is available for Dutton's Quaternary Triangular Mesh (QTM), and both projections of Goodchild's and Otoo's for QTM are found to be two special implementations of EARP. The icosahedral projection and thus the corresponding spherical triangle quadtree partition model are also developed. The partition model is compared with several other global grid models.     

汶川8.0级地震前发震断裂带地震活动特征研究

设定两个不同研究区域,分别就汶川8.0级地震前地震活动特征进行研究,得出以下结论：①至少在2008年5月11日之前的38年时间中,龙门山断裂带中段出现M5.0以上地震空段,汶川巨大地震就发生在这一空段;②第一研究区域强震释放能量出现阶段性梯次减少现象;③至2008年初,估算出第一研究区域地应力积累量已达5.0136×1016J,相当于一次M7.9强震所能释放的能量;④第二研究区域中小地震在龙门山断裂带中段的南端形成了几乎垂直相交的两条地震带,小震活动明显增多.     

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Depth distribution of Moho and tectonic framework in eastern Asian continent and its adjacent ocean areas

It is the essence of the study on the dynamics of eastern Asian continent to investigate the ef-fects of geophysical field and the process of the deep block boundaries, and furthermore, to estab-lish a geodynamic physical-mathematical model based on the d…     

基于移动基准站DGPS整周模糊度快速求解的研究

讨论了移动基准站GPS载波相位差分技术的关键,研究了其确定整周模糊度的方法,设计了检验该技术精度的试验方案,实现了厘米级的相对定位精度。     

An Image Fusion Algorithm Based on Lifting Scheme

Taking the advantage of the lifting scheme＇s characters that can build wavelet translorms tor transforming from integer to integer and the quality of the reconstructing image＇is independent of the topology way adopted by the boundary, an image fusion algorithm based on lifting scheme is proposed. This paper discusses the fundamental theory of lifting scheme firstly and then after taking transform analysis according to a kind of images that need to be confused.     

Le genre Culicia (Scléractiniaire): systématique, écologie et biogéographie au Cénozo?que

Resume. Historiquement, le genre Culicia (Anthozoaire Scléractiniaire) n’était connu, jusqu’à Chevalier (1961), qu’à partir du Burdigalien de Basse-Provence (France). L’examen de récoltes récentes en Aquitaine et de diverses collections montre que l’espèce Culicia parasita (MICHELIN 1847) existe en fait dans cette région depuis l’Oligocène (Chattien), ce qui représente une notable extension de l’éventail stratigraphique du genre. Cette espèce est largement illustrée ici, à partir de spécimens de chaque étage où elle a été reconnue, et des données paléoécologiques sont fournies. Par ailleurs, grace à une révision bibliographique la plus complète possible des références concernant le genre Culicia, et à de nouvelles récoltes effectuées dans le Néogène de l’ouest de la France et de Méditerranée, le hiatus stratigraphique existant dans sa répartition entre le Miocène moyen d’Atlantique–Est et le Pliocène–Quaternaire d’Australie est désormais comblé en grande partie. La question des relations phylétiques possibles entre les espèces fossiles et actuelles de Culicia est posée. Une carte de migration biogéographique est proposée, incluant tous les taxons du genre.      

Structure of the rift basins in the central Gulf of California: Kinematic implications for oblique rifting

We use structural and seismostratigraphic interpretation of multichannel seismic reflection data to understand the structure and kinematic history of the central Gulf of California. Our analysis reveals that oblique strain in the central Gulf formed two tectono–sedimentary domains during distinct deformation stages. The eastern domain, offshore Sonora, is bounded by the East and West Pedro Nolasco faults that may constitute the southernmost segments of the Tiburón Fault System. Within this domain, the dip-slip Yaqui Fault controlled deposition of 3.9 km of sediments in the half-graben Yaqui Basin. The western domain, offshore Baja California, is bounded by the Guaymas Transform Fault, which controlled the accumulation of 1.45 km of sediments within a half-graben that formed the early Guaymas Basin. The tectono–sedimentary activity offshore Sonoran likely ranges from Late Miocene–Pliocene to Late Pliocene time, while activity in the Guaymas Basin commenced in Late Pliocene time. Extinction of the main faults offshore Sonora was nearly coeval to the initiation of the Guaymas Transform Fault. Our results suggest that oblique strain has been accommodated by strain partition since the onset of rifting in the central Gulf. The Guaymas Basin is now a nascent spreading center, but prior to this, it evolved as a half-graben controlled by the Guaymas Transform Fault; such drastic transition is not constrained, but likely occurred during the Pleistocene time and must be localized < 30 km north of the axial troughs. The faults within the central Gulf transpose the Miocene N–S oriented grabens of Basin and Range style preserved onshore in the conjugate rifted margins.     

顾及数据空间分布特性的模糊C-均值聚类算法研究

利用描述空间数据分布的Voronoi图的有关理论分析了样本空间数据分布特性，从理论上论述了样本集中各类样本数差异较大产生的根源，并在此基础上提出了一种顾及数据空间分布特性的模糊C—均值聚类算法。     

基于整周模糊度概率特性的有效性检验

准确确定载波相位整周模糊度是快速高精度GPS定位的关键,已有的检验GPS整周模糊度有效性的方法几乎均是基于其为非随机常量建立的,因而都存在一定的缺陷。本文在研究整周模糊度概率特性的基础上,提出一种基于LABMBAD算法的整周模糊度概率分布函数的检验方法。实际演算表明该方法简单有效,统计概念明确。