基于seam carving技术的图像非等比缩放

数字图像的缩放分全等比例缩放和非等比例缩放。本文主要研究图像非等比例的缩放。传统的图像缩放技术采用插值算法,但是这种算法在缩放时经常会出现马赛克或者图像内容丢失现象。本文研究的seam carving技术首先对图像进行能量描述,使图像中不同内容的景物具有不同的能量,然后找到图像水平和垂直方向的最低能量线,对其进行删除或插入操作,就可以在图像缩放中最大限度地保留图像的重要内容。该方法应用在视频图像4:3到16:9的转换上可以取得很好的效果。通过Matlab实验结果表明,本文的方法在图像进行非等比例缩放时,具有很好的抗畸变性能。     

基于压缩传感理论的彩色图像去马赛克

利用目前最新的压缩传感理论在信号恢复方面的优势,本文提出了一种新型彩色图像去马赛克算法.首先,为了满足压缩传感的约束等距性条件,采用随机马赛克模式得到原始数据;然后把彩色图像去马赛克问题转化为基于压缩传感的信号恢复问题,并充分考虑彩色图像RGB通道的相关性,建立彩色图像的扩展联合稀疏表示模型;最后采用基追踪(BP)算法求解去马赛克问题,得到恢复的真彩色图像.实验证明,本算法能有效减少传统算法恢复图像中出现的锯齿现象,所得到的彩色恢复图像具有更好的视觉效果.客观评价结果显示,本文算法结果的峰值信噪较基于双线性插值和基于梯度等传统算法的结果有明显提高.实验结果验证了本文算法的优越性,显示算法具有重要的应用前景.     

基于复合抛物样条的图像放大算法的设计与实现

图像放大是数字图像处理中常用的技术,图像放大首先对图像进行空间变换,其次对图像进行灰度插值.放大后的图像视觉效果如何在实际应用中显得尤为重要.因此图像放大问题的焦点是如何在图像放大过程中保持良好的视觉分辨率和清晰度.图像放大有许多算法,其关键在于对未知像素点使用何种插值方式.本文提出了一种比传统插值算法更好的算法即复合抛物样条插值,来实现图像的放大.实验结果表明,相对于传统的图像放大算法,本文的算法不仅较好的保留了原始图像的细节信息,而且还提高了放大图像的边缘平滑度,同时也减小了图像放大算法的运算量.     

一种基于压缩感知的图像去马赛克算法

文中提出了一种基于分块压缩感知的图像去马赛克算法.该算法首先将Bayer色彩滤镜阵列采样值等效为压缩感知理论中感知矩阵采样所得的压缩数据.其次通过结合Bayer色彩滤镜阵列自身特点训练分块稀疏字典.最后在训练所得稀疏字典的基础上利用分块压缩感知重构算法便可精确重构出Bayer色彩滤镜阵列采样结果.由于训练所得稀疏字典能有效降低与Bayer色彩滤镜采样阵列之间的相关性,因此文中所提出的图像去马赛克算法能有效对单一Bayer色彩滤镜阵列采样值进行重构.通过实验验证表明：新的图像去马赛克算法明显优于传统插值算法,重构所得彩色图像在去除假色影响的同时能完整保留原始图像的细节信息.     

一种改进的彩色图像去马赛克总变分模型

针对去马赛克总变分正则化模型的不足,提出了一种改进的彩色图像去马赛克总变分模型,将彩色图像的灰度化图像引入到传统彩色图像去马赛克总变分正则化模型中,利用原始对偶不动点算法求解该模型.数值实验结果表明了该模型和算法的有效性和优越性.     

一种消除锯齿的图像放大算法

为了最大程度消除图像放大后出现的锯齿现象,提出了一种新的二次导数连续的多结点立方卷积插值函数,通过增加结点使得插值曲线更加的平滑;同时对插值函数引入逆梯度约束条件,然后根据图像放大的倍数定义一个适当的模板对图像进行卷积操作,自适应的消除图像放大后出现的锯齿现象。实验结果表明,该算法在对图像执行高倍放大时,几乎看不到锯齿,同时图像的清晰度也保持的较好。     

基于三次样条插值的图像放大的离散算法

针对李将云等(2003)提出的图像放大离散算法，分析其不足之处，并对简单的二值图像以及一般的灰度级较少的图像，用三次样条插值方法，提出一套新的离散放大算法．实验结果表明，该算法可以得到较好的放大效果．它适用于灰度级较少的数字图像，尤其是二值图像，并且这种图像放大方法的放大倍数没有限制．     

基于多尺度边缘的血管内超声图像增强算法

血管内超声图像同时具有低对比度和低信噪比的特征,传统的图像增强算法会明显放大噪声.为此,提出一种基于边缘表示的算法来增强血管内超声图像的对比度,采用平滑函数的导数作为小波函数对图像进行二进小波分解,使用小波系数在各尺度间的局部极大值来刻画图像的多尺度边缘,通过拉伸小波系数极大值再重构图像来增强灰度图像的对比度.实验结果表明,本文提出的增强算法在有效增强图像对比度的同时避免了放大噪声,并且可以通过调节不同尺度的拉伸因子来获得不同的增强效果,同时提高了运算速度.     

基于快速残差插值和卷积神经网络的去马赛克算法

针对传统插值法存在的图像细节不能很好恢复的不足,利用卷积神经网络作为残差插值法的后处理操作,提出了一种基于残差插值和卷积神经网络的去马赛克算法。方法分为初始去马赛克和细节恢复后处理两部分。先用改进的基于梯度的快速残差插值法实现初步去马赛克插值,并针对恢复图像中包含了彩色伪影,细节丢失等问题,再使用深度残差网络学习恢复图像与理想全彩色图像之间的映射,实现后处理。在Kodak数据集和IMAX数据集上的实验结果表明,该方法结果在主观视觉特性和客观评价指标两方面相较于传统方法都有明显改进。     

基于区域填充的二值数字图像放大算法

二值数字图像是指仅由2种颜色组成的离散图像。采用一般方法放大二值数字图像,会导致图像的边缘出现模糊与锯齿现象,为此提出一种适合于放大二值数字图像的新算法;采用近邻取样法将图像放大到指定的倍数,通过搜索输入图像确定所有锯齿区域,将其映射到输出图像并进行区域填充;实验结果表明,该算法用于二值数字图像的放大能使图像边缘保持清晰与光滑,与其他方法相比具有明显的优势。     

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…     

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).     

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.     

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.