齐次自相似集的多重分形谱分析

给出了齐次自相似集满足分离性质的一个充分条件,对于直线上的一致压缩映射族,若齐次压缩比小于各个压缩映射平移量之间的最小距离,则相应齐次自相似集满足开集条件,从而它的各种多重分形谱都相等,于是得到了重分形谱的一个简便求法.     

自相似集的Hausdorff维数

本文构造了一类自相似集,利用满足开集条件的压缩自相似映射的性质,解决了一类自相似集的Haus-dorff维数计算问题.     

一类三维Sierpinski海绵的Hausdorff维数

文章构造了一类三维Sierpinski-2n 1(n∈N)海绵,利用满足开集条件的压缩自相似映射的性质,给出它们的Hausdorff维数s=In(n 1)^3／In(1／ε)．     

随机自相似测度的无穷阶量子化维数

当压缩相似映射{Si}i=1N满足开集条件时,随机自相似测度μ的无穷阶量子化雏数D∞（μ）与随机自相似集E的相似维数D之间以概率1的相等关系。     

一类广义Cantor集的Hausdorff维数

研究和推广了自相似分形中最经典的例子Cantor三分集的构造及其Hausdorff维数,利用满足开集条件的压缩自相似映射的性质,解决了一类广义Cantor集的Hausdorff维数计算问题,主要结果是构造了一类广义的Cantor-2k 1(k∈N)分集,并给出它们的维数s=ln(k 1)/ln(1/ε）。     

图有向自相似测度的重分形

研究了图有向自相似集,在开集条件下,获得了该集合关于伴随的自相似测度的重分形分解公式.该结果将Edgar和Mauldin的相应结果所必需的条件——正分离条件做了本质上的修正,使其减弱为开集条件.     

一推广Cantor集在相似压缩不动点处的上凸密度

在分形几何的研究中,上凸密度提供了的研究自相似分形结构理论和工具.文章利用自相似集在相似压缩不动点处的上凸密度的两个等价定义,探讨一推广Cantor集在其相似压缩不动点处的上凸密度,所得结果对一个相关重要猜测给予了有力支持.     

一类具有重叠结构的康托集的维数

席夫定理刻画了开集条件,但不能据此判断一个自相似集是否满足开集条件.作者研究了一类由相似压缩映射S0(x)=x/l, S1(x)=(x+λ)/l和S2(x)=[x+(l-1)]/l(l为素数,λ为有理数且λ∈[0,1])生成的自相似集Eλ的分形结构与分形维数,给出了具有完全重叠与不完全重叠两种重叠类型及判定方法,对每种重叠类型给出Hausdorff维数的求法.通过对这类集合的分析发现,即使"简单"的重叠也会产生非常复杂的结构.     

有限型条件的刻画

若自相似迭代函数系{φj}^mj=1（满足φj（x）=ρjRjx＋bj,bj∈R^d，其中0〈ρj〈1，Rj为d×d正交矩阵）关于不变开集Ω满足有限型条件，K是迭代函数系{φj}^mj=1生成的自相似集．但是，Ω与K的交集可能为空集．本文用构造方法证明存在一个不变开集U，使得U∩K≠φ，且迭代函数系{φj}^mj=1关于不变开集U也满足有限型条件．     

广义自相似集的维数

在减弱了压缩尺度具有正的下确界的条件下,利用配齐降阶方法和网测度的方法,讨论了广义自相似集的Ｈａｕｓｄｏｒｆｆ维数,并得到了广义自相似集的Ｈａｕｓｄｏｒｆｆ维数。     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.