基于Keren配准和插值的快速超分辨率图像重建

为提高图像超分辨率重建技术实时应用的可能性,增强其对配准误差的容忍度,提出了一种基于Keren配准和插值的快速鲁棒超分辨率图像重建算法.该算法将配准后的低分辨率图像根据变换参数映射到高分辨率网格上,再利用模板卷积迭代地填充缺失像素值,从而重建一幅高分辨率图像.将文中算法与非均匀插值法、凸集映射法、鲁棒的迭代后向映射法和...     

基于多幅图像的超分辨率重建方法分析

图像超分辨率重建是指从一幅或多幅低分辨率、低质量图像中产生高分辨率、高质量图像的数字信号处理技术.本文分析了基于多幅的图像超分辨率重建方法,并讨论了目前基于多幅的图像超分辨率重建有待解决的问题.     

基于R滤波器的超分辨图像配准算法

图像配准是超分辨率图像重建的关键.提出了一种基于R滤波器的超分辨率图像重建的三步算法.第一步:对原图进行加窗模糊;第二步:根据全局运动模型配准,计算平移参数和旋转角度,对图像进行平移和旋转;第三步:把序列低分辨率图像配准到同一个坐标系中,重构高分辨率图像.实验表明,三步算法的配准精度和超分辨率图像重建效果较好.     

单帧学习与多帧重建结合的超分辨率盲重建方法

针对模糊退化PSF未知的图像超分辨率重建问题,提出了一种以学习重建结果为参考的模糊图像PSF辨识与重建方法.对学习重建算法获得的退化图像的恢复结果,采用不同尺度的方向滤波提取恢复效果良好的强边缘区域构建参考信息块,引导最大后验概率框架下的超分辨率重建算法按照正确的PSF重建高分辨率图像.以散焦模糊图像为例进行超分辨率实验.实验结果表明,该算法能够准确辨识PSF,提升了图像重建的质量.     

超分辨率重建算法综述

超分辨率重建是指由同一场景的低分辨率退化图像,运用相应的算法重建一幅清晰的高分辨率图像。然而,传统的基于插值、基于重建和基于学习的方法已很难获得进一步的突破。近年新兴的过完备稀疏表示是一种新的图像表示模型,它为解决超分辨率重建中的难点问题提供了新的思路。本文通过分析超分辨率技术的以往研究和最新进展,着重讨论了各算法在重构时的优缺点,并对未来超分辨率重建技术进行了展望。     

校园航拍图像超分辨率重建的粒计算方法

提出了校园航拍图像超分辨率重建的粒计算方法,包括:(1)提出了图像粒化方法,实现图像空间向粒度空间的转化;(2)设计粒之间合并运算和分解运算,构造粒之间的模糊包含关系μ和σ,实现不同粒度空间之间的转化,获取图像的先验知识,指导校园航拍图像超分辨率重建算法的设计;(3)根据自顶向下、自底向上两种模式和图像先验知识,设计校园航拍图像超分辨率重建粒计算算法,实现粒度空间向图像空间的转化.实验验证了提出方法的可行性.     

基于半耦合字典的快速图像超分辨率重建算法

为了提高图像超分辨率重建的效率与质量,考虑到高、低分辨率稀疏表示系数的不同,改进了锚定邻域回归算法,并结合半耦合字典学习算法提出了一种快速图像超分辨率重建算法.首先采用半耦合字典学习算法得到高分辨率字典、低分辨率字典及映射矩阵;再采用岭回归算法求解低分辨率稀疏表示系数,并根据高分辨率稀疏表示系数与低分辨率稀疏表示系数之间的映射关系,得到高分辨率稀疏表示系数;然后,根据输入图像块特征寻找字典中与其最相关的字典原子,计算该字典原子所对应的投影矩阵,进行超分辨率重建.仿真结果表明:提出的算法不仅在重建速度上表现更快,重建图像的质量也得到提高,在客观指标和主观效果上均取得更好的效果.     

基于Keren改进配准算法的IBP超分率重建

提出了一种基于Keren改进配准算法的迭代反投影(iterative back-projection,IBP)超分辨率重建算法.该算法克服了Keren迭代配准算法基于小角度旋转的局限,并在迭代运算过程中引入了权重因子和阈值.权重因子有效地控制了算法的收敛速度,提高算法的稳定性.阈值的引入使得算法效率更高,配准结果更加准确.通过Keren改进配准算法进行配准,再通过IBP算法对配准后图像序列进行超分辨率重建,仿真结果表明,基于Keren改进配准算法的IBP重建具有良好的超分辨率重建效果.     

基于字典学习的超分辨率显微CT图像重建

为提高显微CT重建图像的空间分辨率,提出了一种基于字典学习的超分辨率图像重建算法.首先,将重建图像进行网格细化,并使用面积权值模型实现对投影过程的精确建模.然后,选择高质量的图像作为训练样本,采用K-SVD算法构建图像字典.基于该图像字典,利用正交匹配追踪算法实现对重建图像的稀疏表达,并以此作为稀疏项约束引入到重建算法的目标函数中.最后,使用梯度下降法求解目标函数.实验结果表明:与传统的基于插值的超分辨率重建算法相比,所提算法的超分辨率结果在图像对比度、边缘保持方面具有优势,并且保留了更多的图像高频信息,从而有效提高了重建图像的空间分辨率.     

基于块对称对叠的多幅图像超分辨率重建算法

在进行图像超分辨率重建时,使用多幅图像比使用一幅图像能够得到更好的效果;但是目前基于多幅图像的超分辨率重建算法普遍存在重建速度慢、重建质量不够理想的问题。为此,构造了一种基于块对称对叠(PsyCo)的多幅图像超分辨率重建算法。首先对低分辨率图像序列进行基于ORB的图像配准,再对配准后的图像进行PSyCo重建,最后对重建的图像进行像素灰度最大值融合。实验结果表明,提出的重建算法具有更好的重建效果;并且具有较快的重建速度。     

Markedness and its Interpretation in Language Use

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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