二维图像强度-几何相关系数的统计研究方法

将Vizilter的图像强度-几何相关系数的研究方法加以推广,对随机马赛克图像,采用均方范数作为量化方法,研究了基于投影算子的中心化形态相关系数和几何相关系数更一般的形式,并以Vizilter的各种相关系数作为其特例,研究结果更符合图像的自然构成.此外,通过引入序化函数,研究了相关系数的一些新形式,使得图像相似度比较指标更加丰富.     

扩散形态算子在图像比较中的应用

将Laplacian特征映射和扩散映射的方法应用于图像数据,通过对图像热核及扩散核相关问题的研究,提出了建立扩散形态算子及运用于图像相似性比较问题的基本框架,证明了Pyt'ev形态分析理论中的投影算子及形态相关系数是扩散形态算子及扩散形态相关系数在马赛克图像模式下的特殊情形;与此同时,还对相关算法的具体实现方法和参数选择方式进行了适当改进,使得在图像比较中的相关数据实验结果得到一定的改善.     

关于有限维向量值函数一些注记

首先给出取值于有限维向量空间上的向量值函数的表示形式和有限维向量空间的一种范数.然后利用有限维向量空间上任意两种范数都是等价的性质,讨论了取值于有限维赋范线性空间上的向量值函数的连续、可微、积分及解析的等价关系和表示形式.最后证明了柯西定理、柯西积分公式、高阶导数公式及其表示形式和解析的向量值函数的无穷可微性.     

格分片线性函数的辨识和优化

格分片线性模型由一个实数矩阵和一个 0 - 1矩阵所确定 ,能够表示任意维变量的全体连续分片线性函数 ,其实数矩阵完全由它的局部线性函数的参数向量所组成。这些特点为辨识分片线性函数和利用线性模型的分析方法解决分片线性模型描述的非线性问题提供了极大的便利。该文引入格分片线性模型解决非线性函数的辨识问题。给出了辨识格分片线性函数的实用算法。并对线性约束下的格分片线性函数优化问题提出了通过线性规划算法确定全局最优解的简单方法。这些工作表明 ,用格分片线性函数建模是解决非线性问题的一种有效途径     

高维空间上连续分片线性函数的绝对值表示

高维空间上连续分片线性函数的绝对值表示是一个一直没有能很好解决的问题.在一维空间上连续分片线性函数的绝对值表示基础之上,采用递推的方法,给出了高维空间上连续分片线性函数的绝对值表示;同时证明了该绝对值表示对所有高维空间上连续分片线性函数有效.     

图像相似性度量方法的研究

在Vizilter图像比较方法研究工作的基础上,针对比较图像由于获取条件不同所产生的信息不确定性问题,通过引入图像的标准比较空间,对图像相似性度量问题进行了研究.提出了基于距离测度、相关系数及复合投影的图像相似性度量方法.基于图像标准比较空间的相似性度量工作不仅对Vizilter的研究成果进行了推广,同时也给出了一些新的研究思路和方法.     

向量均衡问题的一个投影迭代解法

将用于求解欧氏空间上数量均衡问题的一种投影迭代法进行了推广,并将这种推广的投影迭代法用于求解欧氏空间上的向量均衡问题.利用非线性标量化函数,将向量优化问题化为相应的数量优化问题,研究了投影迭代法对向量均衡问题的收敛性.结果表明推广的投影迭代法对满足一定条件的向量均衡问题是收敛的.     

张量典型相关分析

针对典型相关分析用于图像特征融合时,不仅消耗大量时间,且常常产生协方差阵奇异的问题,提出了一种快速算法.该算法将图像看作张量空间RM(×)RN中的二阶张量,建立方差和协方差,根据准则函数进行相关投影分析,将图像矩阵投影到2个向量空间的张量积空间.图像识别实验结果表明,该算法不仅提高了计算效率,而且能取得更高的识别率.     

基于核方法协同表示的高光谱图像分类

为进一步利用高光谱图像在同一区域内像素点的相似特性完成地物分类,提出了一种基于核方法协同表示与绝对距离融合的分类算法。通过核函数将原始数据投影到高维核空间,在特征空间中用全部训练样本表示待测样本,再计算吉洪诺夫正则化下待测像元的重构残差和每个类别表示系数绝对值向量,使用不同权重予以融合作为分类依据。在实验中使用Indian Pines和Pavia University两种高光谱图像数据对该方法进行实验验证,实验结果表明:与原协同表示(CRC)及支持向量机(SVM)相比,改进后分类算法总体分类精度和平均分类精度都有更好的表现,均达到94%以上,具有较好的鲁棒性。     

低维空间上分片线性函数的逼近因子与剖分数

引入了分片线性函数及矩阵行列式的解析表示,通过低维欧氏空间几何模型和等距剖分提出逼近因子的概念,并基于差值因式给出对应矩阵行列式的代数余子式和矩阵模的计算方法.依次证明了输入空间的剖分数与1元、2元和3元分片线性函数的逼近因子均无关,但剖分数与分片线性函数及其逼近精度却有关.     

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.     

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.     

A computer generator for randomly layered structures

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

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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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。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

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