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1.
田卓  佘青山  甘海涛  孟明 《计量学报》2019,40(4):576-582
为了提高复杂背景下面部信息的识别性能,提出了一种面向人脸特征点定位和姿态估计任务协同的深度卷积神经网络(DCNN)方法。首先从视频图像中检测出人脸信息;其次设计一个深度卷积网络模型,将人脸特征点定位和姿态估计两个任务协同优化,同时回归得到人脸特征点坐标和姿态角度值,然后融合生成相应的人机交互信息;最后采用公开数据集和实际场景数据进行测试,并与其他现有方法进行比对分析。实验结果表明:该方法在人脸特征点定位和姿态估计上表现出较好的性能,在光照变化、表情变化、部分遮挡等复杂条件下人机交互应用也取得了良好的准确性和鲁棒性,平均处理速度约16帧/s,具备一定的实用性。  相似文献   

2.
基于深度数据的空间人脸旋转角度估计   总被引:1,自引:0,他引:1  
提出一种基于三维人脸深度数据的人脸姿态计算方法。利用人脸的深度数据以及与其一一对应的灰度图像,根据微分几何原理和相应的曲率算法与人脸数据中的灰度特征对人脸面部关键特征点定位,进而计算出人脸姿态在三维空间中的3个姿态角。实验证明该方法能在姿态变化情况下实现对人脸旋转角的准确估计,为进一步的人脸识别和表情分析提供基础。  相似文献   

3.
提出了一种利用三维人脸模型匹配二维人脸图像的分层人脸识别方法和基于模糊数学的人脸姿态角度估计算法.对多姿态二维图像进行姿态空间划分,利用主成分分析方法(PCA)形成多姿态特征脸.识别过程首先估计测试图像姿态和模糊姿态角,在估计的姿态空间内采用基于PCA的方法进行第一层识别得到候选个体,然后利用候选个体的三维模型结合模糊姿态角产生虚拟图像,利用相关进行第二层识别.实验结果表明,该方法对姿态的变化有较好的鲁棒性.  相似文献   

4.
王娟  江艳霞  唐彩虹 《光电工程》2012,39(10):32-39
实际人脸跟踪过程中,光照和姿态的变化、背景颜色干扰等因素都会极大地削弱颜色特征的有效性,从而造成跟踪的不稳定.针对该问题,本文提出了一种以颜色和轮廓分布为线索的粒子滤波人脸跟踪算法.该算法主要有三个方面的特点:第一,在粒子滤波基本框架下,引入新的用直方图描述人脸轮廓的方法,有效解决了光照、人脸旋转、部分遮挡问题对跟踪的影响,并且能及时有效地重新捕获由于大面积遮挡等原因而丢失的目标.同时采用实时调整每帧图像特征点个数,有效提高了跟踪效率.第二,针对背景干扰问题,提出了一种抑制相似背景颜色干扰的方法.第三,本文还提出实时更新模板的方法来提高跟踪的准确性.实验证明本文算法对人脸跟踪具有很好的效果.  相似文献   

5.
提出一种将肤色分割与灰度图像对称变换相结合的有效的人脸特征定位方法.为降低背景和人脸姿态的影响,在传统人脸肤色分割基础上,利用Blob分析及椭圆拟和方法判断并剔除无效区域,并将待选人脸区域初步校正为竖直;直接利用色度信息在待选人脸区域中分割并检测嘴唇;接着,采用灰度图像的对称变换检测双眼的待选位置;以嘴唇和待选双眼的位置为依据,提出了基于人脸几何模型知识的双眼匹配代价函数并利用组合优化方法检测真实双眼;最后,对人脸上其它器官的进行精确定位.实验结果表明,该方法对于头发遮挡、大倾斜角以及眼镜干扰具有较强的鲁棒性.  相似文献   

6.
为了较好地解决被部分遮挡的人脸的检测问题,提出一种基于组件距离匹配度函数的人脸检测方法.该算法首先采用基于支持向量机的Adaboost算法即AdaboostSVM算法对输入图像进行人脸各组件的检测,然后根据组件间距离的均值和方差构建组件距离匹配度函数,并提出基于组件距离匹配度函数的组件整合验证算法,在此基础上对被遮挡的组件的位置进行估计,进而实现部分遮挡的人脸的检测与定位.实验结果表明,该方法能够提高部分遮挡的人脸的检测性能与速度,能够在复杂背景下对被部分遮挡的人脸进行较为准确的定位与检测.  相似文献   

7.
黄启宏  王帅  刘钊 《光电工程》2007,34(11):93-97
利用拓扑理论中的单形定义,本文提出了一种针对人脸图像本征维数的估计方法.首先给出一个简单的几何模型,说明在不同的姿态和光照条件下人脸图像可看成一个弯曲流形;然后把人脸流形模型近似为一个单纯复形,获得相应的单形数目;最后,利用单纯复形中单形的最大维数是单纯复形的维数的性质,从而估计出人脸图像的本征维数.实验结果表明,本文方法跟经典方法,如分形方法、熵估计方法及k-近邻图方法等相比较,在人脸图像本征维数估计方面是有效的和准确的.  相似文献   

8.
人随着年龄的增长,外貌特征会发生相应的变化。而这种变化导致人脸识别率急剧下降,为此本文提出一种自动估计人脸年龄的方法,即利用流形学习方法从高维的人脸图像空间中的提取低维年龄流形作为人脸图像的年龄特征,然后利用支持向量回归方法构建全局年龄函数,最后用所得的年龄函数估计出未知人脸图像的年龄值。  相似文献   

9.
本文利用相机对目标物体特征点的测量信息解决机器人相对位置和姿态的估计问题。首先,针对机器人运动过程中相机获得的目标物体连续图像,利用扩展Kalman滤波器估计特征点的三维信息。然后,在SE(3)空间上设计了一个非线性位姿观测器。利用得到的特征点三维信息构造了 Lyapunov函数,并解耦成分别和姿态误差以及位置误差相关的两部分。利用Lyapunov稳定性原理设计了观测器的姿态误差和位置误差补偿律,证明了观测器在平衡点处是渐近稳定的。最后,通过数值仿真实验验证了所提算法的有效性。  相似文献   

10.
在基于立体视觉的立式风洞飞机尾旋姿态测量过程中,遮挡问题是困扰测量的一个难题.遮挡问题的常用解决方法需要恢复连续的被遮挡空间,计算量大,且不容易保证精度.针对特征点测量的遮挡问题,本文提出一种基于信用度分类的解决方法,在被遮挡空间搜索感兴趣点的最佳近似,并且通过引入信用度因子的组合计算,控制和提高最佳近似点的计算精度.文中分析了辅助计算点的测量误差所带来的搜索定位困难,信用度因子的引入可以弱化不精确辅助点对搜索结果的影响,使搜索过程主要依赖可靠的点进行.最后,通过仿真实验分析了该方法的可靠性,并说明其在飞机尾旋运动测量实验中对测量结果的有效改善.  相似文献   

11.
We associate a variety of innovations with the term "Industry 4.0". The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...  相似文献   

12.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

13.
ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.  相似文献   

14.
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……  相似文献   

15.
Al2O3-ZrO2 nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.  相似文献   

16.
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……  相似文献   

17.
Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.  相似文献   

18.
We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.  相似文献   

19.
Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.  相似文献   

20.
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.  相似文献   

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