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1.
由于图像间光谱特性的差异,对图像配准的精度产生严重的影响,因此该文提出了一种基于改进灰度熵的SAR图像自动配准算法。文中首先对SAR图像进行配准前的预处理,提取图像掩模,然后计算图像行和列的灰度熵,将其作为图像的特征信息完成图像间的配准,提出了配准优化算法的完整步骤,并利用多种方法对配准结果进行评价。实验证明该方法可以有效克服图像间亮度不均的影响,充分利用了像素的有用信息,具有很高的配准精度和配准效率,是一种正确可行的图像配准算法。  相似文献   

2.
针对传统互信息图像配准容易产生局部极值,以及传统梯度互信息配准方法计算量大等问题,在互信息和梯度方法基础上构建了一种改进的梯度互信息方法,该方法直接统计梯度图像的互信息,有效地将图像梯度信息和灰度信息结合起来,不仅保证了配准精度,而且较传统梯度互信息方法减少了计算量。在参量优化的过程中,针对传统粒子群优化算法易陷入局部极值的缺点,提出了改进的粒子群优化算法,该算法在传统粒子群优化算法基础上引入混沌优化思想和遗传算法中的杂交思想,不仅能够有效抑制局部极值,而且加快了收敛速度。多种红外与可见光图像配准实验结果证明,文中提出的算法能够有效提高配准精度和速度。  相似文献   

3.
谷雨  徐英  陈华杰 《信号处理》2016,32(6):669-675
为解决基于隐性度量的图像配准算法初始配准误差大容易引起失配的问题,本文提出了一种融合显性度量和隐性度量的多模图像分层配准算法。首先采用金字塔分解算法得到低分辨率待配准图像。然后在每一层金字塔图像中,先采用互信息作为显性度量,利用粒子群算法获得初始的配准参数;以此作为初始值,采用基于隐性度量的配准算法,利用融合粒子群和鲍威尔搜索法的优化算法获取更准确的配准参数。基于低分辨率图像计算得到配准参数后,先对高分辨率待配准图像进行变换,然后利用提出的上述算法进行参数优化,根据每层得到的配准参数计算最终的配准参数。最后,采用可见光与红外图像、多波段SAR图像进行了配准实验。实验结果表明,提出的算法适用于多模图像配准,能够减小配准误差,具有一定的适用性。   相似文献   

4.
基于互信息的红外与可见光图像快速配准   总被引:3,自引:0,他引:3  
针对灰度和图像特征存在较大差异的可见光和红外图像配准,给出了一种基于归一化互信息与小波变换相结合的快速图像配准算法。实验表明,该算法加快了配准过程,较利用原图像配准速度提高了约一个数量级,且配准结果具有较高的准确性和稳定性。可见该算法适用于多光谱图像配准。  相似文献   

5.
基于改进粒子群优化算法的互信息图像配准   总被引:1,自引:0,他引:1  
为了实现快速精确的图像配准,提出了基于改进粒子群优化算法的互信息图像配准方法,以互信息作为图像配准的相似性测度,使用改进的PSO算法来求解配准所需的空间变换参数.改进的粒子群算法引入组织的概念把整个种群划分为多个子群体共同进化,并引入变异运算减少算法陷入局部最优.把改进的粒子群优化算法应用到医学图像配准领域上来,实验结...  相似文献   

6.
基于IPSO和综合信息的医学图像配准新方法   总被引:2,自引:0,他引:2  
针对医学图像配准中采用互信息作为配准相似度函数存在配准精度不高和收敛速度慢等问题,根据图像灰度和空间结构信息,构造了一种新的基于互信息和改进型形态学梯度算子的信息配准测度函数,采用一种适用于医学图像自动配准的改进型粒子群优化(IPSO)算法,给出了一种新的基于IPSO的医学图像配准算法。实验结果表明,该配准算法稳定性好、收敛速度快,在多模态医学图像自动配准中是可行的。  相似文献   

7.
一种改进的基于互信息的自动图像配准算法   总被引:1,自引:0,他引:1  
提出了改进图像配准的基于互信息的算法,首先将参考图像和待配准图像分解到小波域并二值化,以归一化互信息作为相似性测度进行配准.配准参数搜索作用SPSA算法和鲍威尔算法相结合的优化策略.实验证明本算法可以快速、精确且不需要人工干预地实现两幅图像的配准.  相似文献   

8.
一种图像快速配准算法的研究   总被引:3,自引:0,他引:3  
在基于小波分解和互信息测度的图像配准方法的基础上,提出一种改进的快速图像配准算法。首先,对图像进行小波分解,以分解后的图像的近似分量进行配准,利用互信息最大化作为相似性测度,并结合粒子群优化算法和鲍威尔算法为优化策略搜索最优配准参数。实验结果显示,此方法在得到较高的配准精度和鲁棒性的情况下,还大大减少了运算量,提高了配准的速度。  相似文献   

9.
苏娟  李彬  王延钊 《电子与信息学报》2016,38(12):3282-3288
为克服图像间灰度差异、旋转差异和尺度差异对SAR图像配准精度的影响,该文利用均匀区域在SAR图像中的灰度统计特性,提出一种基于稳定封闭均匀区域的SAR图像配准算法。首先基于多尺度非线性扩散理论,提取得到轮廓保持性较好的封闭均匀区域;然后构建具有仿射不变性的区域特征,采取基于多边形拟合的区域粗匹配方法和基于重合度的区域精匹配方法,实现由粗至精的区域匹配;最后用匹配区域的质心点构建图像变换模型。实验结果表明,该算法配准精度高,能有效克服待配准图像之间的灰度差异、旋转差异和尺度差异,对噪声具有较好的适应性。  相似文献   

10.
蚁群算法和Powell法结合的多分辨率三维图像配准   总被引:5,自引:0,他引:5  
基于互信息的配准方法具有精度高,鲁棒性强的特点,成为近年来图像配准研究的热点.但基于互信息的目标函数存在许多局部极值,为配准的优化过程带来了很大的困难.该文提出了一种蚁群算法和Powell法相结合的多分辨率搜索优化算法.该算法以互信息作为相似性测度,采用基于小波变换的多分辨率策略,将蚁群算法与Powell法结合起来对三维的CT,MR图像进行了配准.实验结果表明,这种方法能够有效地克服互信息函数的局部极值,大大地提高了配准精度,达到亚像素级.  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

13.
In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.  相似文献   

14.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

15.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

16.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

17.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

18.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

19.
This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.  相似文献   

20.
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.  相似文献   

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