一种二值图像的快速细化算法

提出了一种适应于二值图像的快速细化算法，该算法利用边缘跟踪，根据边缘跟踪特点所设计的判断规则及单向链表结构存储边缘信息等技术，大大地加快了细化速度，而且占内存少，当仅需对目标模式进行细化处理时，该算法更为有效。     

基于像素标识细化方法抗笔画边缘毛刺的研究

对基于像素点标识的新细化算法在抗笔画边缘毛刺方面的作用进行了深入研究．基于像素点标识的新细化算法中细化保留点的确定是基于像素标定信息矢量的，而影响像素标定信息矢量的领域非常大，边缘无规律的毛刺对标定信息矢量的影响被平均化了，该细化算法的细化结果受边缘毛刺的影响最小，对比研究证实了这一点．给出了对比研究的结果，研究了该算法抗笔画边缘毛刺的机理．     

一种基于边缘知识的雷达图像匹配定位算法

针对低信噪比实孔径雷达图像的特点，选用适于提取多尺度稳定边缘的Ｃａｎｎｙ算子，结合具有视觉非线性的门限准则、Ｎｅｖａｔｉａ细化和跟踪准则及Ｈｏｕｇｈ变换，提取可靠稳定的边缘特征描述，根据可见光参考图提取与ＳＡＲ图像共性的稳定边缘特征的知识以及稳定边缘的知识描述，提出了一种基于边缘知识的雷达图像与可见光图像匹配定位算法．实验结果表明，该算法能可靠地完成雷达图像的匹配定位．     

一种基于边缘知识的雷达图像匹配定位算法

针对低信噪比实孔径雷达图像的特点，选用适于提取多尺度稳定边缘的Ｃａｎｎｙ算子，结合具有视觉非线性的门限准则、Ｎｅｖａｔｉａ细化和跟踪准则及Ｈｏｕｇｈ变换，提取可靠稳定的边缘特征描述，根据可见光参考图提取与ＳＡＲ图像共性的稳定边缘特征的知识以及稳定边缘的知识描述，提出一种基于边缘知识的雷达图像与可见光图像匹配定位算法，实验结果表明，该算法能可靠地完成雷达图像的匹配定位。     

基于细化指纹图像特征提取的改进算法

文章深入研究了细化指纹图像细节点提取算法，针对常规提取算法中存在一定数量的伪细节点问题，提出了一种改进的细化指纹图像细节点提取算法。该算法在原有提取算法的基础上，在细节点提取中采用了邻域查找删除、边缘删除等措施。实验表明，该算法显著地减少了伪细节点的提取，是一种较为理想的细化指纹图像细节点提取算法。     

陶瓷基片检测中Robert边缘细化算法

陶瓷基片检测中为了对亚像素进行精确定位,需要对基片图像进行灰度边缘细化.为了得到保留信息的细化灰度边缘,对边缘细化算法进行了研究,提出了Robert边缘细化算法.先对基片图像进行均值滤波,然后用Robert算子进行两次边缘检测,最后将两次检测结果进行减法运算得到边缘细化的陶瓷基片图像.实验表明,该算法可以得到允许范围内的单像素连通的细边缘,保留边缘灰度信息,为下一步对图像进行亚像素细分,提高测量精度打下良好的基础.     

普通Sobel边缘细化算法的改进

Sobel边缘检测算法检测到的边缘较粗,需细化处理,而普通Sobd边缘细化算法细化后的边缘会不连续,细化效果也不理想。为了更加突出边缘,更好地保留边缘信息,本文对Sobel边缘细化算法做了改进,测试证明改进使边缘检测的效果得到了改善。     

扫描图矢量化研究与实现

结合大比例尺扫描地形图的特点，研制了扫描图矢量化系统。系统将边缘检测与二值化有机地结合起来，实现了基于边缘检测的图像二值化方法；提出了针对水平、垂直线段的基于完整线段跟踪的线段细化算法，使得经细化处理的线段从整体上最佳逼近于原线段位置，减少了矢量化所带来的处理误差；经处理后的线段没有曲折和毛刺，也减少了大量的后期处理工作量。     

边缘宽度细化与交叉皮层模型结合的图像分割算法

针对弱边缘图像分割中交叉皮层模型产生目标几何尺寸失真等问题,提出了一种基于边缘宽度细化与交叉皮层模型结合的图像分割算法。该算法借助prewitt边缘算子和边缘斜坡模型,细化图像边缘宽度。在此基础上,利用二维直方图将交叉熵扩展至二维空间,以获得交叉皮层模型的最优分割阈值。实验结果表明,该算法不仅能克服边缘模糊的影响,对弱边缘图像进行精确分割;而且处理速度也大幅提升了。     

从多面体图象到线画图表示

如何在单幅线画图上进行空间多面体形状信息的定量恢复，魏在其论文［１］中已给出了主要的理论结果。为了从所摄入的多面体图象得到相应的线画图，要对图象进行一系列处理，包括：提取边缘、细化、跟踪及拟合。本文着重对该过程所涉及的图象处理问题及有关算法作一较为详细的讨论和介绍。     

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