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1.
支持向量机(SVM)花费大量时间用于对非支持向量样本的优化.根据支持向量都是位于两类边界的靠近分类超平面的样本点,本文提出首先利用基于中心距离比值法排除大部分远离分类超平面的样本,然后以最小类间距离样本数作为测度进一步选择边界样本.得到包含所有支持向量的最小样本集,构成新的训练样本集训练SVM.将提出的算法应用于解决医学图像奇异点检测问题.实验结果表明.该算法减小了训练样本集的规模,有效地缩短了SVM训练算法的时间.同时获得了较高的榆出率.  相似文献   

2.
图像分割是图像理解、模式识别、计算机视觉等研究方向的一个重要研究内容。图像分割的方法有很多,将支持向量机(Support Vector Machine,SVM)应用于图像分割已是一种较为广泛的分割方法,但该方法大多采用人工方式来选取训练样本,降低了图像分割的自适应性,且有可能影响图像分割的质量,因此基于支持向量机的图像分割方法的研究内容是如何自动选择足够多且分布良好的训练样本,并自动进行类别标注。文章提出一种基于分水岭的图像分割训练样本的自动选择和标注方法,分水岭分割区域的中心点可以看作支持向量机的训练样本,将选取的训练样本对照分割参考图中的像素点进行类别标记。然后对训练样本进行训练,其中选择图像的颜色特征和纹理特征作为训练样本的特征属性。文章采用的彩色图像来自Berkeley图像数据库以及互联网,从实验结果可以看出文中提出的方法可取得很好的分割结果。  相似文献   

3.
为了提升图像去雾算法的效果和适应性,提出了一种基于简单线性迭代聚类(SLIC)超像素分割和支持向量回归(SVR)的单幅图像去雾算法.首先,将雾霾图像进行超像素分割,对于每个超像素块,取其最大通道内的最大值作为局部大气光的估计,并使用引导滤波优化大气光图的边缘.然后,采集清晰户外图像并切割成块,利用大气散射模型为其加入不同程度的雾作为训练样本,提取对比度、饱和度、直方图均衡度和最小通道均值4种特征,利用支持向量回归算法训练传输参数估算模型.实验结果表明,所提算法有效地恢复了图像的对比度和颜色饱和度,同时无论是在主观视觉效果方面,还是在结构相似度和峰值信噪比等客观评价指标方面,所提算法均优于现有传统算法.  相似文献   

4.
在研究聚类算法与极限学习机的基础上实现了一种具有模糊C均值聚类算法(FCM)预分类的核极限学习机(KELM)及其在彩色图像分割中的应用.该算法采用模糊C均值聚类算法预分类训练样本,再提取其图像特征作为特征属性对核极限学习机进行训练产生分类器,进而对彩色图像进行分割.经实验验证,该算法分割彩色图像在分割速度和精度上优于FCM预分类的BP人工神经网络以及FCM预分类的支持向量机,是一种高效的彩色图像分割算方法.  相似文献   

5.
为了提高遥感图像分类精度,提出一种模糊均值聚类(FCM)和最小二乘支持向量机(LSSVM)相融合的遥感图像分类方法(FCM-LSSVM).首先对遥感图像样本进行模糊均值聚类,得到隶属度矩阵,然后根据隶属度矩阵选择遥感图像的训练样本,最后将训练样本输入到最小二乘支持向量机进行学习,并采用粒子群优化最小二乘支持向量机参数,建立遥感图像分类模型.通过仿真实验对算法性能进行测试,结果表明FCM-LSSVM提高了遥感图像分类效率和分类精度.  相似文献   

6.
针对目前无人机影像提取内河目标存在的人工解译依赖高等问题,提出一种基于超像素空间关系特征的内河设施提取算法.首先,采用简单线性迭代聚类(SLIC)算法分割无人机影像生成超像素;其次,对分割得到的超像素区域进行颜色及纹理特征计算,基于支持向量机(SVM)实现水陆分割;最后,基于空间关系特征实现拦河坝的自动提取.实验结果表明,该方法能够有效提取无人机影像中的拦河坝区域,对内河航运发展和航道设施监测具有一定的应用价值.  相似文献   

7.
图像分割是模式识别、计算机视觉等领域的重要研究内容,也是图像信息处理的难点和热点之一.以孪生支持向量机(TSVM)与极坐标复指数变换(PCET)理论为基础,提出了一种基于局部像素特征分类的图像分割算法.该算法首先对局部像素窗口进行PCET,并将PCET系数幅值作为图像的像素级特征;然后利用指数交叉熵阈值技术确定训练样本,并进一步训练出TSVM分类模型;最后利用已获得的TSVM分类模型对原图像像素进行分类处理,从而获得图像的最终分割结果.实验结果表明,该算法可以获得较好的图像分割结果.  相似文献   

8.
提出一种基于核可能性c-均值算法的支持向量机分类算法,该算法改进了SVM训练过程中噪声和孤立点的敏感问题.其基本思想是:用核可能性c-均值算法对每个模式类训练样本进行聚类,得到不同的可能性度量值,根据得到的可能性度量值对训练样本进行修剪,删除具有较低可能性度量值的训练样本,最后用生成的新训练样本训练支持向量机.实验结果表明,该算法可以有效地解决由噪声和孤立点引发的分类错误问题以及重要样本的错分问题.  相似文献   

9.
信息的来源多种多样,其中图像是比较重要的一种。随着信息中越来越多地出现数字图像,如何对其进行处理成为国际上的研究热点。图像处理过程包含有图像编码、图像增强、图像压缩和图像分割等许多环节。近年来,学者们对图像分割问题给予了极大关注。介绍了支持向量机的概念,将图像分割看做像素分类,将支持向量机用于图像的分割,包括样本的选择、特征的提取,训练支持向量机,最终实现了基于支持向量机的图像分割算法。结果表明,支持向量机能够很好地将图像目标分割出来。  相似文献   

10.
为使支持向量机(SVM)更加适用于在线文本分类应用,利用SVM在小训练样本集条件下仍有高泛化能力的特性,结合文本特征向量在特征空间中具有聚类性的特点,提出一种用语义中心集代替原训练样本集作为训练样本和支持向量的SVM语义SVM.文中给出了语义中心集的生成步骤、语义SVM的在线学习算法框架,以及基于SMO算法的在线学习算法的实现.实验结果表明,相对于标准SVM,语义SVM及其在线学习算法不仅在线学习速度和分类速度有数量级提高,而且在分类准确率方面具有一定优势.  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.
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   

15.
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   

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

19.
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   

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   

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