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1.
基于改进FCM和形态学的浮选泡沫形态特征提取   总被引:2,自引:0,他引:2  
针对浮选过程中因气泡粘连及形状不规则导致泡沫形态特征难以提取的问题,提出一种基于改进模糊C均值(fuzzy C-means,FCM)聚类和数学形态学的浮选泡沫形态特征提取方法。引入聚类有效性指数及特征散度对模糊C均值聚类算法加以改进,并利用改进的聚类算法对泡沫图像进行聚类,得到泡沫大致区域。依据灰度分布和形状特征,采用面积重构开闭算法对图像进行除噪处理。基于形态重构方法思想,提出采用高低精度距离变换方法,同时,结合改进面积重构变换提取标志图像,进而利用分水岭算法对泡沫图像进行分割。通过测量分割区域和标定像素提取泡沫形态特征,并与浮选工艺参数做相关性分析。研究结果表明,该方法能够准确地分割粘连泡沫,且提取的泡沫形态特征能有效反映浮选工况。  相似文献   

2.
针对传统FCM算法在图像分割中存在的过度依赖初始聚类中心、计算复杂度高等问题,结合层次聚类与直方图峰值检测,提出了一种新的FCM图像分割算法.首先根据图像灰度直方图统计信息对图像进行层次聚类,然后将得到的聚类中心作为FCM算法的初始聚类中心对图像进行分割.该算法无需预先设置聚类数目,能自动搜索全局最佳聚类中心.实验结果表明,相比传统FCM算法和峰值检测的FCM算法,该算法不仅可以有效地提高图像的分割效率,而且分割结果更加精确.  相似文献   

3.
针对CT医学图像灰度不均匀的特点,研究了基于改进的模糊聚类和ChanVese模型的图像分割.该分割模型综合利用基于空间信息的FCM算法、图像局部区域信息以及Chan-Vese模型,通过最小化能量函数的方式来进行曲线演化.基于空间信息的FCM算法对曲线的演化起到了一定的收敛作用,并且局部区域信息提高了分割质量.分割模型还考虑了分割效果和计算效率,降低了算法的时间复杂度,提高了算法的执行效率,从而提高了灰度不均匀图像分割的精度.  相似文献   

4.
提出一种基于图的层次聚类算法实现脑组织磁共振图像的自动分割。首先,采用基于图的分割方法对脑组织MR图像进行初始分割。由于脑组织MR图像各类组织结构分布复杂,尤其是脑脊液和灰质区域细节信息丰富、结构变化多样,分割结果中存在过分割现象。因此,利用对偶树复小波变换高频子带信息构造基于图的分割方法中参数k的自适应取值函数,避免图像平滑区域分割后产生大量小区域。然后,以层次聚类算法合并分割得到的小区域,解决基于图的方法分割脑组织MR图像中存在的过分割问题。最后,通过大量真实脑组织MR图像实验证明该方法在脑组织MR图像分割中的准确性和稳定性。  相似文献   

5.
改进的快速模糊C均值聚类的图像分割方法   总被引:3,自引:0,他引:3  
传统的模糊C均值(FCM)聚类算法广泛用于图像的自动分割,但该算法没有考虑像素的灰度和空间特征,对噪声和伪斑点图像不可能取得好的分割效果.提出一种改进的算法,在快速的FCM聚类的基础上,运用邻域像素的灰度相似度和聚类分布统计构造新的隶属函数,对图像进行二次聚类分割.该算法具有以下优点:1)有效地抑制了噪声的干扰;2)减少了图像的伪斑点;3)把误分类的像素很容易地纠正过来.对两种类型图像的实验分割结果表明该方法对噪声和伪斑点具有很强的鲁棒性和对像素聚类的正确性.  相似文献   

6.
边缘信息指导下的半模糊聚类图像分割方法   总被引:2,自引:0,他引:2  
提出了一种利用边缘信息的半模糊均值聚类的图像分割算法,它先用边缘检测和区域生长算法对图像进行一次预分割,确定聚类的初始参数,然后在这个基础上对“边缘”部分的点采用模糊聚类、非“边缘”部分使用分明聚类,避免了模糊聚类时初始参数设定的盲目性,减少了迭代时的计算量,提高了迭代收敛速度.除灰度特征外,聚类时还利用了点到类的距离特征,较好地保持了分割图像的连续性.直接观察对比多幅图像的分割实验结果可以明显地发现,该算法较常用的Cksu方法、二维熵阈值分割方法以及FCM方法的分割结果更准确.就Lena图像而言,该算法的收敛速度也比一般的FCM快了将近一倍.  相似文献   

7.
目前的FCM类型的算法聚类数目的确定需要聚类原形参数的先验知识,否则算法就会产生误导.为了提高图像分割算法的抗噪性能,用K均值聚类算法简单、快速的优点对模糊C均值聚类算法进行改进.结合图像的邻域信息,对图像的直方图作均衡化处理,改善图像质量,通过自适应滤波,降低噪声对分割效果的影响.先用K均值聚类算法对图像进行分割,快速的获得较为准确的聚类中心和初次分割图像,避免了FCM算法中初始聚类中心选择不当造成的死点问题.用邻域灰度均值信息代替传统模糊C均值聚类算法中的灰度信息,对K均值聚类得到的图像作二次分割.该方法能更好的抑制噪声的干扰,提高了聚类算法的分割精确度.  相似文献   

8.
模糊C均值聚类(FCM)算法常用于图像的聚类分割中,但常规的FCM算法对噪声的抑制能力较差。许多改进的FCM图像聚类分割算法虽能有效地抑制图像中的椒盐噪声和高斯白噪声,但是对图像中出现的大颗粒背景噪声的抑制效果仍然较弱。提出了一种融合图像滤波技术的FCM图像分割算法,根据噪声尺寸选择滤波窗大小,利用FCM聚类结果构造噪声判定矩阵并设计噪声判定规则,实现滤波窗内噪声点滤波操作。该算法针对人工合成的含噪灰度图像和实际的纤维图像进行了图像分割实验,实验结果表明:本文算法能有效抑制图像中的噪声,特别是大颗粒背景噪声,能获得满意的分割结果。  相似文献   

9.
该文将图像过分割技术与图像显著性相结合,提出了一种基于图像显著性与灰度不一致性的目标自动提取方法。该方法可在没有任何人工干预的情况下准确地提取出图像的感兴趣目标。首先,通过像素不一致性因子和邻域不一致性因子确定出图像的不一致性种子点和一致性种子点;然后,使用等价类划分的方法对两类种子点分别进行生长,得到不同的等价类,合并残余类之后得到图像的初分割块;最后由初分割结果结合显著性检测算法提取出完整的感兴趣目标。考虑到像素的局部邻域信息,首次将图像的底层特征——像素的灰度不一致性应用于图像分割,并以此为基础进行目标提取。实验表明,该方法能够有效地实现显著目标的自动提取。  相似文献   

10.
传统的模糊C均值(FCM)聚类算法广泛用于图像的自动分割,但它有两个缺陷:一是收敛速度过慢;二是当图像的目标和背景像素拥有相近的灰度值,具有相似的隶属度,导致了图像边界区域的不连续和模糊.针对该问题,提出一种改进的算法,在快速FCM聚类的基础上,利用粗糙集理论中的上近似和下近似的概念来描述图像的目标和背景,引入粗糙熵的概念,选择合适的阈值,对图像进行精确分割.实验结果表明,这种算法可以达到满意的分割效果.  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.
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   

13.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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