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1.
在传统类间散布矩阵理论的基础上,提出了类间的两两散布矩阵和类间重叠系数矩阵.传统的类间散布矩阵对于两类或多类的类别均值和全局均值之间距离值相近时难以区分,而且对于方差大而分类信息差的向量也无能为力.类间重叠系数矩阵可以剔除方差大而分类信息差的向量,两两类间散布矩阵则用于区分类别均值和全局均值之间距离值相近的向量.实验证明该方法生成的特征向量取得的分类效果较好.  相似文献   

2.
提出了利用Mahalanobis距离进行人脸表情识别的方法.首先将待分类的图像样本集进行坐标变换,使得变换以后类间离散度尽可能大而类内离散度尽可能小,即使变换以后的Fisher准则函数取得极大值,在新的坐标下求每个待分类样本到各类均值向量的Mahalanobis距离,从而将待分类的样本归到Mahalanobis距离最小的类中去,通过实验得到了平均80.25%的识别率.  相似文献   

3.
提出了利用Mahalanobis距离进行人脸表情识别的方法.首先将待分类的图像样本集进行坐标变换,使得变换以后类间离散度尽可能大而类内离散度尽可能小,即使变换以后的Fisher准则函数取得极大值,在新的坐标下求每个待分类样本到各类均值向量的Mahalanobis距离,从而将待分类的样本归到Mahalanobis距离最小的类中去,通过实验得到了平均80.25%的识别率.  相似文献   

4.
文章提出了一种基于集成矩阵距离(AMD)和类间散布矩阵构造的模块2DPCA人脸识别方法.针对原模块2DPCA算法的不足,使用类间散布矩阵代替总体散布矩阵,求得最佳特征向量并对图像进行特征提取;采用集成矩阵距离的度量方式计算特征图像的相似度,实现人脸分类.在ORL人脸库上的实验结果表明,同2DPCA和普通模块2DPCA相...  相似文献   

5.
提出了一种样本间的相似性度量方法,并将这种相似性度量信息附加到Fisher线性判别的类内、类间离散度矩阵,使得Fisher判决准则在使类内距离达最小、类间距离达最大的同时,也使类内相似度达最小、类间相似度达最大,获得比原始Fisher判别更好的投影矩阵.实验证明,与Bagging集成的Fisherface比较,该方法显示出更好的识别率.  相似文献   

6.
针对缺失数据的有效填充问题,提出利用模糊C-均值聚类(FCM)算法的隶属度矩阵作为待填数据的加权权重.首先使用同一属性均值对缺失数据作预填充,再进行FCM以得到每个类别的隶属度矩阵,最后用该矩阵作为权重去乘以每个类别的属性均值,得到最终的填充数据.在UCI数据实验中,将FCM填充算法与k近邻(KNN)填充算法作对比分析,结果表明,FCM填充得到的均方根误差总体小于KNN填充.  相似文献   

7.
基于直觉模糊C-均值的客户聚类和识别方法   总被引:1,自引:1,他引:0  
客户聚类和识别是大规模客户化生产中产品/服务快速有效设计的基础.考虑客户需求信息的不确定性,提出了基于直觉模糊C-均值的客户聚类算法.针对传统基于欧式距离的C-均值聚类方法无法计算直觉模糊数组间距离的缺点,采用直觉模糊交叉熵方法处理算法中的距离计算问题.同时,直觉模糊交叉熵还用来计算新客户和各客户类间的偏好相似度,进行客户识别.最后以某工程机械企业服务开发中的客户聚类和识别为例,验证了所提方法的有效性.  相似文献   

8.
针对缺失数据的有效填充问题,提出利用模糊C-均值聚类(FCM)算法的隶属度矩阵作为待填数据的加权权重.首先使用同一属性均值对缺失数据作预填充,再进行FCM以得到每个类别的隶属度矩阵,最后用该矩阵作为权重去乘以每个类别的属性均值,得到最终的填充数据.在UCI数据实验中,将FCM填充算法与k近邻(KNN)填充算法作对比分析,结果表明,FCM填充得到的均方根误差总体小于KNN填充.  相似文献   

9.
为了在多维聚类分析中运用有效距离度量方法表征数据对象的邻近度,提出一种协方差测距(covariance distance measure analysis,CDM)算法,首先,采用模糊C均值(fuzzy c-means,FCM)方法对数据对象赋予权值,得到每个样本点相对类别特征的隶属度,再依据隶属度计算每个样本的差异度;其次,为了使类别分离最大化,用样本点同关联类别的协方差距离度量代替模糊聚类中欧式距离度量作为优化问题的第一个标准,使相似数据对象更为接近;最后,用样本点间的协方差距离度量作为第二个优化标准,使相异数据相互隔开,交替固定变量迭代计算最优解,使聚类指标和距离度量学习参数同时得到优化,获得更好的聚类结果。在不同数据集上的实验结果表明,与FCM-Sig和UNCA算法相比,CDM算法在聚类准确性和算法收敛性方面均有更好表现。  相似文献   

10.
为了提高数据挖掘的聚类准确度,提出了一种基于菌群优化的K均值(K-means)聚类算法.采用K均值算法建立数据聚类模型.根据聚类类别数设定多个聚类中心坐标.设定所属类别距离阈值,然后计算待聚类点和所有中心点距离来划分该聚类点的类别.根据参与聚类各节点和各自中心点的距离值建立适应度函数.引入菌群优化算法对K均值聚类过程进...  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.
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 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   

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.
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   

18.
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   

19.
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   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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