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1.
在小波变换理论的基础上,提出了一种结合小波分解和脉冲耦合神经网络(PCNN)的遥感图像融合新方法.首先对两幅已经配准的原始遥感图像进行小波多尺度分解,得到低频子带系数和各带通子带系数;其次对低频子带系数采取一种基于边缘的方法以得到融合图像的低频子带系数;对各带通子带系数提出了一种改进的基于PCNN的图像融合方法来确定融合图像的各带通子带系数;最后通过逆小波变换重构图像得到融合后的图像.仿真结果和评价指标结果表明,此方法更好地保留了原图像中的有用信息,提高了融合图像的质量.  相似文献   

2.
在小波变换理论的基础上,提出了一种结合小波分解和脉冲耦合神经网络(PCNN)的遥感图像融合新方法.首先对两幅已经配准的原始遥感图像进行小波多尺度分解,得到低频子带系数和各带通子带系数;其次对低频子带系数采取一种基于边缘的方法以得到融合图像的低频子带系数;对各带通子带系数提出了一种改进的基于PCNN 的图像融合方法来确定融合图像的各带通子带系数;最后通过逆小波变换重构图像得到融合后的图像.仿真结果和评价指标结果表明,此方法更好地保留了原图像中的有用信息,提高了融合图像的质量.  相似文献   

3.
在小波变换理论的基础上,提出了一种结合小波分解和脉冲耦合神经网络(PCNN)的遥感图像融合新方法.首先对两幅已经配准的原始遥感图像进行小波多尺度分解,得到低频子带系数和各带通子带系数;其次对低频子带系数采取一种基于边缘的方法以得到融合图像的低频子带系数;对各带通子带系数提出了一种改进的基于PCNN的图像融合方法来确定融合图像的各带通子带系数;最后通过逆小波变换重构图像得到融合后的图像.仿真结果和评价指标结果表明,此方法更好地保留了原图像中的有用信息,提高了融合图像的质量.  相似文献   

4.
综合Canny法与小波变换的边缘检测方法   总被引:6,自引:0,他引:6  
提出一种Canny法与小波变换相结合的边缘检测方法.首先,对源图像进行小波分解,在不同分解层上对高频子图像用小波模极大法进行边缘检测,对低频子图像用Canny法进行边缘检测,然后采用一定的融合规则将这两个边缘图像融合在一起,得到一幅完好的边缘图像.这种边缘检测方法结合了小波变换法和Canny法的优点,对用不同方法得到的两种边缘信息进行融合,从而有效地抑制了噪声,保留了连续、清晰的边缘.实验结果表明,这种结合方法要优于单独使用Canny法或小波变换法.  相似文献   

5.
基于融合技术的小波变换和数学形态学的边缘检测算法   总被引:1,自引:0,他引:1  
针对传统的基于小波变换的边缘检测法无法提取低频区域完整连续的边缘,并且会丢弃包含一些重要细节的高频区域,同时受到噪声的影响而导致边缘提取效果不佳的问题,提出了一种基于融合技术的小波变换和数学形态学的边缘检测算法.在小波域中,对低频子图像采用数学形态学进行边缘检测,对高频子图像先进行小波降噪再采用小波模极大值法进行加权边缘检测,最后采用一定的融合规则对高、低频边缘子图像进行融合.实验结果表明,该方法用于图像边缘提取,不但能有效去除噪声干扰,又能突出边缘细节,边缘定位连续准确.  相似文献   

6.
提出了一种图像边缘检测的方法.本算法将小波变换和数学形态学相结合,并采用简单的融合策略,确定图像边缘位置.在小波域中,对高频子图像用小波模极大法进行边缘检测,对低频子图像用数学形态学法进行边缘检测,然后采用一定的融合规则分别对高、低频边缘子图像进行融合,最后进行小波逆变换重构融合图像.实验结果表明,该算法融合规则简单,泛化能力强,能有效地抑制噪声,较好地再现图像的边缘信息,是一种有效的图像边缘检测算法.  相似文献   

7.
针对遥感图像融合提出了一种基于小波稀疏基的压缩感知算法,该算法利用IHS变换法得到的高空间分辨率融合图像有尖锐边缘及小波变换能较好的保持光谱信息的优势,将多光谱图像的I分量和全色图像进行小波变换;根据其高低频分量的特点,对其低频分量采用小波稀疏基的系数加权融合法,高频分量采用边缘提取法分别进行融合,最后进行小波逆变换和IHS逆变换得到最终融合结果。实验结果表明,不同的小波稀疏基系数对融合结果有较大的影响,且所选算法的融合效果优于系数最大值法及传统融合方法。  相似文献   

8.
提出一种新的基于边缘检测的图像融合方法.该方法利用Canny算子进行边缘检测,将边缘检测图像的逻辑值与小波变换进行结合.在小波变换域内,对低频和高频子图像采用区域融合的方法.最后,进行小波逆变换得到融合图像.通过主观评价和包括熵、均方根误差、峰值信噪比和互信息等客观评价标准进行评价,结果表明,基于边缘检测的图像融合方法融合效果较好,对于模糊部分不同的源图像进行融合具有一定的通用性.  相似文献   

9.
基于脊波变换的手指静脉图像增强研究(英文)   总被引:1,自引:0,他引:1  
针对人体手指静脉图像的结构和特点,提出一种基于脊波变换的图像增强算法。该算法对手指静脉图像小波域各高频子带系数进行脊波变换,利用非线性新脊域系数确定法对脊域系数进行处理,然后对各高频子带进行脊波逆变换和小波图像重构。该算法对手指静脉二维曲线奇异处理、边缘增强等具有较好的效果,克服了小波变换在高维曲线奇异和方向选择上的不足。通过与传统的二维离散小波变换边缘增强法和自适应调整系数的脊波变换方法作比较,实验结果表明本算法具有更好的手指静脉图像效果。  相似文献   

10.
一种基于四元数小波变换的图像融合方法*   总被引:1,自引:0,他引:1  
目的基于四元数小波变换理论提出了一种新的图像融合方法。方法基本思想主要包括3步:首先,对图像进行四元数小波分解,得到各个尺度下的高频子带和低频子带。其次,对高频子带和低频子带分别采用区域最大值法和系数平均的融合准则,得到融合的四元数小波融合系数。最后,利用四元数小波逆变换得到融合图像。结果用所提方法得到了6组测试图像在主观和客观上的融合结果。结论实验表明,所提方法比离散小波变换、对偶数复小波变换和曲线波变换的图像融合方法更有效。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
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.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
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。  相似文献   

18.
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.  相似文献   

19.
20.
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  相似文献   

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