首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 172 毫秒
1.
图像的自相似性研究   总被引:2,自引:1,他引:2  
提出一种判断图像自相似性强弱的方法.该方法定义了一个自相似系数来表征图像的自相似性.自相似系数越大,图像的自相似性越强.依此方法判断出图像的自相似性,为图像是否适合分形图像压缩方法提供一个参考依据.实验结果表明,使用该方法能很好地对图像自相似程度作出判断.  相似文献   

2.
基于支持向量机语义分类的两种图像检索方法   总被引:2,自引:0,他引:2  
为了更好的解决基于内容的图像检索问题,提出了2种基于语义的图像检索方法.第1种是基于支持向量机(SVM)语义分类的图像检索方法.该方法首先提取训练图像库的底层特征信息,然后利用SVM对所提取的特征进行训练,构造多分类器.在此基础上,利用分类器对测试图像自动分类,得到图像属于各个类别的概率,实现图像检索.第2种是利用图像自动标注方法进行检索.在基于语义的图像自动标注中,先对训练集进行人工标注,对测试图像利用SVM分类器进行分类,并找到与该图像最相似的N张构成图像集,对该图像集的标注进行统计,找到关键词,从而提供概念化的图像标注以用于检索.通过在标准图像检索库和自建图像库上的实验结果表明,以上2种基于语义的图像检索方法是高效的.  相似文献   

3.
阈值法是一种被广泛使用的图像分割方法.本文从图像中信息的变化情况出发,提出一种基于图像清晰度评价的新颖的自适应阈值分割方法.该方法采用清晰度评价函数作为阈值化后图像内灰度相似性变化的度量方法,通过反复迭代并结合皮尔逊相关性直至找到最佳的分割阈值.通过多组图像数据尤其低对比度图像,包括钢板表面轻微缺陷等图像进行了测试对比.结果表明:相比传统阈值分割方法及其改进算法,在低对比度图像的处理上,本文方法能够自适应地准确找到合理阈值,具有优异的图像分割性能.  相似文献   

4.
基于二维图像和多点统计方法的多孔介质三维重构研究   总被引:10,自引:0,他引:10  
提出了一种基于多孔介质二维薄片图像和多点统计方法的多孔介质三维重构方法.将微米精度的多孔介质二维薄片图像作为初始的训练图像,利用多点统计方法重构其下层图像.将每次获得的下层图像作为新的训练图像,利用多点统计方法继续重构该训练图像的下层图像.二维重构图像的每个像素对应成三维空间的一个体素,依次叠加每层的二维重构图像得到最终的三维多孔介质图像.将该方法应用于砂岩样品的三维重构,通过与真实情况下砂岩体数据的比较发现,该方法重构的多孔介质具有与其相似的孔隙结构特征.  相似文献   

5.
利用颜色和纹理特征的图像过滤方法   总被引:3,自引:0,他引:3  
随着互联网络和多媒体技术的发展,色情图像的传播越发猖獗.为了有效地防止色情图像的传播,本文中提出一种综合利用颜色和纹理特征的色情图像过滤方法.该方法根据色情图像的颜色和纹理特征,建立肤色模型和皮肤模型对图像进行检测识别.利用该方法对752幅色情图像和4000幅正常图像进行过滤实验,结果表明该方法具有较高的准确率.  相似文献   

6.
在数字图书馆的各类数据查询中,图像检索占有十分重要的地位.为了更好地实现图像检索任务,本文建立了一种新的基于内容的图像检索方法.这种图像检索方法先对图像进行模块化,再根据各个图像块计算出其相应的DCT系数并形成特征向量,再通过k-均值聚类方法生成用于最终检索的12维特征向量,最后利用卡方距离进行相似度差异的检测完成图像检索.为了模拟本文方法在数字图书馆中的使用效果,自建了图像检索系统和小型图像数据库.实验结果表明,本文所提出的图像检索方法具有较高的检索准确性,可以用于数字图书馆中的图像检索.  相似文献   

7.
介绍一种新的由两幅不同角度的参考图像生成另一幅新的视角图像的图像生成方法 .该方法在极线几何的基础上 ,通过研究物体在 3个不同透视投影平面上对应点之间的相互关系 ,得到描述不同图像上对应点关系的一个三线性张量 .由此张量和参考图像便能得到新图像和参考图像之间的关系 ,进而生成新的视角图像 .和其他基于图像的二次投影方法相比 ,这里仅需要两幅参考图像 ,且实现方法简单快速 .实验给出了令人较满意的效果  相似文献   

8.
双向凝胶电泳图像在成像过程中会受到噪声干扰,影响图像质量,严重阻碍图像分析和蛋白质识别.为了提高图像质量,对图像降噪方法的研究是十分必要的.笔者比较了几种常用的滤波方法(空域滤波和小波滤波)对凝胶图像的降噪效果.通过比较各种小同的降噪方法,探索适合凝胶图像降噪的方法.  相似文献   

9.
研究了离散图像的连续表示及重建问题.首先利用弦理论,给出了图像的连续表示形式,然后利用付里叶变换实现了图像连续表示及重建的快速算法,接着将它们应用于图像无级缩放、图像平滑、边缘检测、角点检测,并与传统离散图像处理方法的实验结果进行了比较.实验结果表明:利用图像连续表示方法处理离散图像可以得到不差于传统的离散图像处理方法处理的结果,此方法使离散图像的解析法处理成为可能.  相似文献   

10.
为了精确描述由于高分辨率卫星在轨动力学环境不确定干扰造成的光学传感器拍摄遥感图像退化的过程,在自然图像的运动模糊点扩散函数检测方法的基础上,提出一种基于遥感图像梯度特征的运动模糊检测方法. 该方法利用图像分割和梯度特征选择处理区域,对遥感图像进行预处理,使图像的梯度特征更加符合检测方法的先验知识,采用基于概率分布的点扩散函数估计方法获得图像的退化模型. 结果表明该方法提高了图像模糊的检测精度,获得了更准确的遥感图像运动模糊点扩散函数的检测结果.   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 Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号