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1.
针对单一生物特征识别方法易受干扰、应用受限制等问题,提出了一种基于虹膜和人脸的多生物特征融合方法以提高身份识别的精度及可靠性.该融合方法利用 Log-Gabor 相位编码算法和Laplacianfaces 算法对虹膜和人脸进行特征提取及匹配,然后在匹配层对两种生物特征的匹配得分值使用最小最大概率机策略进行融合,最后利用融合后得分值进行决策.该方法与单生物特征识别方法相比,识别性能明显提高.在UBIRIS虹膜库和ORL人脸库构成的多模生物特征库中进行了测试,实验结果表明:该方法的等错误率可降低到 0.28%,比单一虹膜和单一人脸方法分别降低了0.69%和 1.62%,与采用传统融合策略的方法相比,等错误率也降低了 0.2%以上.  相似文献   

2.
基于特征融合的三维人脸识别   总被引:2,自引:0,他引:2  
针对单一的人脸特征在识别中的局限性,将基于深度图像的全局特征和基于测地线的局部特征进行融合,以提高识别率.将三维人脸点云转换为深度图像后进行预处理,然后使用主成分分析法(PCA)找到一个低维的特征脸空间,依照最近邻法则将其与库集样本进行匹配,所得结果即为全局特征;将测试样本与模板人脸进行匹配,得到35个特征点,这些特征...  相似文献   

3.
基于FPGA的嵌入式SOPC方案进行高速图像采集与门禁控制,设计开发了人脸门禁考勤控制管理系统.构建了图像采集与控制的硬件平台;给出基于Gabor小波变换的个性化特征提取算法,采用不同频率和方向角的Gabor小波变换提取人脸个性化特征;阐述了基于弹性模板匹配和SVM的分层次人脸比对识别方法;在VC++环境中,采用不同的阈值对系统进行测试.结果表明,该系统实现了特征向量的降维,可以有效提高人脸正确识别率,降低了人脸比对误识率,并提升了识别速度.  相似文献   

4.
针对当前人脸识别算法的运行速度和识别准确率的矛盾,提出一种基于双向主成分法(Bidirectional PCA,BD-PCA)和K近邻法K-NN(K-nearest neighbor)的人脸识别算法。在VC6.0平台下基于ORL人脸库进行实验,首先利用双向PCA算法对训练人脸样本和测试人脸样本进行方向和列方向降维并提取特征脸;然后用K近邻方法对特征脸进行人脸匹配。实验表明,提出的算法在有效降低运算时间的同时,又能取得很高的识别准确率,具有一定的可行性。  相似文献   

5.
鉴别局部特征分析及其在人脸识别中的应用   总被引:1,自引:0,他引:1  
由于传统的鉴别主分量分析(DKL)算法中,主分量分析(PCA)基于全局特征,难以提取人脸的局部特性,该文提出鉴别局部特征分析算法.该算法中,局部特征分析(LFA)代替PCA作为线性鉴别分析(LDA)的前端.一方面,LFA在保留大部分全局信息的同时提取局部特征.另一方面,它为信号提供一种有效的低维表示,增强LDA在小样本问题中的数值稳定和推广性能.文中结合开集模式的人脸认证领域,在PoliceFace、OCRLab人脸库和它们的组合库上对新算法和DKL算法进行实验比较.实验表明,通过结合LFA和LDA,新算法明显降低认证错误率在PoliceFace库上,等错误点错误率降低43.10%;在OCRLab库上错误率降低25.87%;在组合库上错误率降低33.16%.  相似文献   

6.
在图像分类问题中,传统的稀疏表示算法只考虑样本整体信息,忽略样本局部结构信息;此外,稀疏表示算法要求测试样本与训练样本的人脸图像要一致对齐,当姿势与角度发生变化时分类效果明显下降.针对这些问题,提出了一种改进L2正则化稀疏表示算法.首先,通过求解最小二乘法得到稀疏系数矩阵;然后,计算样本重构残差,用稀疏度量公式量化样本之间的稀疏性;最后,在保持样本稀疏性的同时增加了样本类与类之间的局部判别信息,进而提高样本的分类性能.为了验证算法的有效性,在ORL、FERET和FEI人脸数据库与Stanford 40 Actions数据库和Caltech-UCSD Birds (CUB200-2011)数据库上进行实验.实验结果表明,该方法在不同的人脸数据库和扩展视觉数据集上取得的分类结果均优于传统稀疏表示算法及其他常用分类算法.  相似文献   

7.
针对分辨率变化、视角变化和认证集单样本等实际条件下的人脸识别问题,提出了一种基于回归的人脸识别算法。该算法采用核主成分分析法(kernel principal component analysis)分别提取侧面低分辨率和正面高分辨率人脸特征,利用 Procrus-tes 分析建立每一种侧面视角低分辨率 KPCA 特征和正面高分辨率 KPCA 特征间的映射关系,从而获得对应的回归模型。根据这些回归模型,即可得到测试侧面低分辨率人脸对应的正面高分辨率 KPCA 特征,并通过最近邻分类器进行识别。在标准图库上的实验表明,与基于线性模型的人脸识别对比算法相比,本文所提算法识别率提高了4%至36%,而在线测试时间仅比最快的对比算法多1.087 ms。  相似文献   

8.
针对主成分分析(PCA)未充分利用样本类别信息及线性鉴别(LDA)在小样本时识别率低的问题,提出了一种基于PCA和LDA相融合的人脸识别算法。该算法首先将输入人脸图像进行几何位置规范化和灰度分布均衡化预处理;然后利用PCA算法将人脸训练图像投影到低秩特征子空间,利用LDA算法计算类间离散度大、类内离散度小的特征子空间,从而获得PCA-LDA的人脸融合特征空间;最后将训练样本、测试样本投影至融合的特征空间,并利用最近邻准则实现对测试样本的识别。实验结果表明,该算法能够有效融合PCA和LDA的优势,提高系统识别的鲁棒性和效率。  相似文献   

9.
生物识别技术是利用人自身具备的生物特征进行身份鉴别的技术.与其他的生物认证技术相比,人脸识别具有更直接、友好、方便的优点.而人眼的自动定位是人脸识别研究中一个基本且非常重要的课题,特别对背景复杂、倾斜、旋转、脸部表情、姿势变化的人脸灰度图像,提出了一种改进的人眼快速定位的算法,该算法首先使用最大类间方差阚值方法确定人脸上下边界,然后利用垂直积分投影确定人脸上下边界,再利用复杂度分析在人脸区域中生成包含眼睛的极小人眼区域,最后在这候选小区域内利用模板匹配的方法精确定位眼睛.这样可以大大减小模板匹配时的计算量.在BioID_TEST_V1.2人脸数据库中实验,该算法的准确定位率95%以上.  相似文献   

10.
针对人脸姿态、光照和表情等各方面原因引起人脸识别率不高的问题,提出了一种基于单样本特征点形变成冗余样本的压缩传感人脸识别方法.将人脸图像信号进行小波变换得到系数的稀疏表示,采用高斯随机测量矩阵进行测量得到离散人脸单样本,基于特征点形变人脸三维模型生成冗余样本,通过稀疏特征点正交匹配追踪非线性重建算法重建冗余图像进行人脸识别.仿真实验结果表明,所提出的算法相对于同类算法,时间复杂度较低、精确度较高、鲁棒性较强,且随复杂环境变化,其优势更明显.  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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