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1.
针对传统稀疏表征分类器只有在训练样本足够多时才会对特征变化不敏感的缺点,提出一种Shearlet多方向自适应加权融合的稀疏表征人脸识别算法。为了提取局部方向信息并降低特征维数,首先利用Shearlet变换对图像进行多尺度、多方向分解,获得子带系数矩阵,然后根据子带系数矩阵方差的大小对同一尺度的方向子图按主方向排序,利用子带系数矩阵的能量和均值特征对排序后的人脸子图进行加权融合,最后为了使得表征系数矢量具有更为显著的稀疏性,进一步利用融合特征构造字典。在ORL、FERET和YALE人脸库中做了多组实验,结果表明,该方法能增强对外界环境变化的鲁棒性,同时可以提高人脸的识别率。  相似文献   

2.
兰伟  何松柏 《包装工程》2017,38(3):180-186
目的解决当前图像融合算法大都直接在图像的像素灰度空间上进行融合,导致融合图像存在视觉效果差及算法鲁棒性不强等问题。方法文中提出改进的Shearlet变换耦合频率特征的多聚焦图像融合算法。将Shearlet变换(ST)和非下采样小波变换(NSWT)进行融合,形成改进的Shearlet变换(ST-NSWT)对源图像分解,获取图像的低、高频子带系数;构建区域能量模型,对源图像之间的低频子带系数进行相关性度量,完成低频子带的融合;对高频子带的频率特征进行分析,建立方差模型、平均梯度模型、空间频率模型,分别对源图像的灰度相关性、清晰度相关性及活跃度相关性进行测量,完成高频子带的融合,最后通过ST-NSWT逆变换,输出融合图像。结果与当前多聚焦图像融合算法相比,文中算法融合的图像能较好地保留更多的细节及边缘信息,使融合图像具备更佳的视觉效果。结论所提算法具有更好的融合质量,可用于遥感探测与包装印刷检测等领域。  相似文献   

3.
葛雯  姬鹏冲  赵天臣 《光电工程》2016,(4):73-77,83
针对红外与可见光图像融合时细节信息提取不充分、算法复杂度高等缺点,本文提出一种降低算法复杂度、丰富细节信息的基于非降采样剪切波变换(NSST)和非负矩阵分解(NMF)的红外与可见光图像融合算法。该方法根据NSST算法对源图像分别进行多尺度、多方向稀疏分解,分别得到低频部分和高频部分。对低频部分采用基于改进的NMF融合规则;对高频部分采用拉普拉斯能量和视觉敏感度系数相结合的融合规则。最后,对低频融合部分和高频融合部分执行NSST逆变换得到最终的融合图像。实验结果表明,该融合方法不仅可以保证融合图像的清晰度,同时还可以缩短算法的运行时间。  相似文献   

4.
针对图像融合中参数优化的问题,提出了一种基于多目标粒子群优化算法的多传感器图像融合方法。首先采用非采样Contourlet变换(NSCT)对源图像进行多尺度、多方向分解;然后选取图像融合的客观评价指标为优化目标函数,采用多目标粒子群优化算法对低频系数的融合参数进行优化,带通方向子带系数采用取绝对值最大的融合规则;最后通过NSCT逆变换得到融合图像。分别对多聚焦图像融合和红外与可见光图像进行融合实验,并对融合图像进行主客观评价,实验结果表明,得到的融合图像具有较好的主观视觉效果和客观评价指标。  相似文献   

5.
基于复合激励模型的Surfacelet域多聚焦图像融合方法   总被引:1,自引:1,他引:0  
针对基于传统多尺度分析对图像分解得到的方向子带数量较少,抑制噪声能力弱,融合图像边缘连贯性不好的缺点,本文提出一种基于Surfacelet变换和复合激励模型的多聚焦图像融合方法。通过分别将两幅图像经Surfacelet变换后得到若干不同频带子图像,该方法根据低频子带和高频子带的特点,建立复合激励模型,即分别把改进的拉普拉斯能量和与空间频率作为复合型PCNN的外部激励,采用复合型PCNN优选融合系数,改善融合效果。获取的融合图像的灰度级分布更加分散,图像纹理连贯,细节突出。实验结果表明,该算法克服传统多聚焦图像融合方法的缺陷,客观评价指标显示本方法优于Laplace、DWT和PCA等传统图像融合方法。  相似文献   

6.
提升静态小波域内多聚焦图像融合算法   总被引:1,自引:1,他引:0  
李华锋  柴毅  张晓阳 《光电工程》2011,38(3):131-137,144
针对同一场景的多聚焦图像融合问题,提出了一种新的基于提升静态小波变换(Lifling Stationary Wavelet Transform,LSWT)的多尺度积图像融合算法.该方法在选择融合图像的低频子带系数时定义了一种新的改进拉普拉斯能量和(Sum Modified-laplacian,SML),设计了一种基于拉...  相似文献   

7.
孔玲君  张志华  曾茜  王茜 《包装工程》2018,39(19):216-222
目的鉴于非下采样剪切波变换NSST的红外与可见光图像融合的结果存在细微特征缺失问题,提出一种基于NSST和SWT的红外与可见光图像融合算法,以提升融合图像的质量。方法首先分别对红外与可见光图像进行NSST分解,各得到一个低频系数和多个不同方向、尺度的高频系数。然后低频系数分别通过SWT分解得到新的低频系数和高频系数,通过SWT分解得到的新的低频系数和高频系数分别采用采用线性加权平均法和区域平均能量取大的融合策略,融合结果再进行SWT逆变换得到低频系数融合结果。高频系数采用区域平均能量取大的融合策略进行融合。最后通过NSST逆变换得到最终的融合图像。结果通过仿真实验结果表明,文中算法与NSST,SWT和NSCT等算法相比,融合图像在主观视觉上的红外目标更突出,图像细节更清晰,且在IE, AG, QAB/F, SF和SD等评价指标上也最优。结论文中算法的融合结果能更好地表现源图像的目标信息和细节纹理信息,表明该算法具有优越性。  相似文献   

8.
基于NSCT和PCNN的红外与可见光图像融合方法   总被引:8,自引:2,他引:6  
提出了一种基于非采样Contourlet变换(NSCT)和脉冲耦合神经网络(PCNN)的红外与可见光图像融合方法.首先用NSCT对已配准的源图像进行分解,得到低频子带系数和各带通子带系数;其次对低频子带系数采取一种基于边缘的方法以得到融合图像的低频子带系数;对各带通子带系数提出了一种改进的基于PCNN的图像融合方法来确定融合图像的各带通子带系数;最后经过NSCT逆变换得到融合图像.实验结果表明,本文方法优于Laplaeian方法、小波方法和传统的NSCT方法.  相似文献   

9.
叶玫  刘盈 《包装工程》2019,40(1):218-227
目的针对基于Contourlet变换的融合算法在边缘上易出现吉布斯现象,使其融合图像产生几何失真的问题,设计一种非下采样方向滤波器组耦合局部Laplacian能量和的图像融合算法。方法首先,结合多小波变换(multi-wavelet transform,MWT)与非下采样方向滤波器组(Non-Subsampled Direction FilterBank,NSDFB),将图像分解为3个高频方向系数和1个低频系数。对于低频系数,采用局部修正的Laplacian能量和(Local Sum-Modified-Laplacian,LSML)与脉冲耦合神经网络(Pulse couple neural network,PCNN)组合的LSML-PCNN模型来完成低频信息的融合。对于高频系数,通过提取低频和高频子带边缘,并利用系数绝对最大值法作为依据,实现高频系数的融合。结果实验数据表明,与当前图像融合方案相比,所提算法具有更高的融合质量,得到的融合图像边缘更加清晰和完整。结论所提算法拥有较高的融合视觉效果,可改善图像的对比度和分辨率,在图像处理领域具有一定的参考价值。  相似文献   

10.
结合边缘特征的遥感图像融合   总被引:3,自引:2,他引:1  
曲波(Curvelet)变换是一种更适合于图像处理的多尺度几何分析(MGA)方法,具有很强的方向性.结合 HSI变换将其应用于全色图像和多光谱(MS)图像融合可以更好地表示图像中的有用特征.首先对多光谱图像进行 HSI变换,得到亮度分量 I,对全色图像和 I 分量进行曲波变换得到粗尺度系数和细节尺度系数,对全色图像的粗尺度系数和细节尺度系数进行叠加,计算归一化的全色曲波系数直方图,定义边缘有效因子,利用全色图像的特征信息对融合图像的粗尺度系数进行处理,对细节尺度系数采用函数对弱边缘进行增强,对新的曲波系数设计融合规则进行融合,逆变换后得到新的亮度分量 Inew,用 Inew 替代原亮度分量 I 进行逆 HSI 变换得到最终融合结果,采用统计类指标对融合结果进行评价.实验结果表明,该方法在保持光谱信息和提高空间分辨率上都有较好的效果.  相似文献   

11.
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.  相似文献   

12.
13.
A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.  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.
On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……  相似文献   

16.
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   

17.
In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M2(B,C), (W,Mo)2(B,C), M3(B,C), M23(B,C)6 type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm2. The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K1 mill housing of bar mill.  相似文献   

18.
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   

19.
The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...  相似文献   

20.
Several researches have been reported about the characteristic of β-Ga2O3 nanowires which was synthesized on nickel oxide particle. But indeed, recent researches about synthesis of β-Ga2O3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst. In this work, Gallium oxide (β-Ga2O3 ) nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700 - 1000℃ using the iron, nickel, copper, cobalt and zinc oxide as a catalyst, respectively. The β-Ga2O3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850, 900 and 950℃ in all the catalysts. But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst. As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods, and its diameter increased. From these results, we could be proposed that the growth mechanism of β-Ga2O3 nanowires was changed with synthesis temperature of nanowires. Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM, FE-SEM, EDX and XRD.  相似文献   

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