To address the non-negativity dropout problem of quaternion models, a novel quasi non-negative quaternion matrix factorization (QNQMF) model is presented for color image processing. To implement QNQMF, the quaternion projected gradient algorithm and the quaternion alternating direction method of multipliers are proposed via formulating QNQMF as the non-convex constraint quaternion optimization problems. Some properties of the proposed algorithms are studied. The numerical experiments on the color image reconstruction show that these algorithms encoded on the quaternion perform better than these algorithms encoded on the red, green and blue channels. Furthermore, we apply the proposed algorithms to the color face recognition. Numerical results indicate that the accuracy rate of face recognition on the quaternion model is better than on the red, green and blue channels of color image as well as single channel of gray level images for the same data, when large facial expressions and shooting angle variations are presented.

In this paper, we study the problem of a batch of linearly correlated image alignment, where the observed images are deformed by some unknown domain transformations, and corrupted by additive Gaussian noise and sparse noise simultaneously. By stacking these images as the frontal slices of a third-order tensor, we propose to utilize the tensor factorization method via transformed tensor-tensor product to explore the low-rankness of the underlying tensor, which is factorized into the product of two smaller tensors via transformed tensor-tensor product under any unitary transformation. The main advantage of transformed tensor-tensor product is that its computational complexity is lower compared with the existing literature based on transformed tensor nuclear norm. Moreover, the tensor $\ell_p$ $(0<p<1)$ norm is employed to characterize the sparsity of sparse noise and the tensor Frobenius norm is adopted to model additive Gaussian noise. A generalized Gauss-Newton algorithm is designed to solve the resulting model by linearizing the domain transformations and a proximal Gauss-Seidel algorithm is developed to solve the corresponding subproblem. Furthermore, the convergence of the proximal Gauss-Seidel algorithm is established, whose convergence rate is also analyzed based on the Kurdyka-$\L$ojasiewicz property. Extensive numerical experiments on real-world image datasets are carried out to demonstrate the superior performance of the proposed method as compared to several state-of-the-art methods in both accuracy and computational time.

The affine rank minimization problem consists of finding a matrix of minimum rank that satisfies a given system of linear equality constraints. Such problems have appeared in the literature of a diverse set of fields including system identification and control, Euclidean embedding, and collaborative filtering. Although specific instances can often be solved with specialized algorithms, the general affine rank minimization problem is NP-hard, because it contains vector cardinality minimization as a special case.In this paper, we show that if a certain restricted isometry property holds for the linear transformation defining the constraints, the minimum rank solution can be recovered by solving a convex optimization problem, namely the minimization of the nuclear norm over the given affine space. We present several random ensembles of equations where the restricted isometry property holds with overwhelming probability, provided the codimension of the subspace is Ω(r(m + n) log mn), where m, n are the dimensions of the matrix, and r is its rank.The techniques used in our analysis have strong parallels in the compressed sensing framework. We discuss how affine rank minimization generalizes this pre-existing concept and outline a dictionary relating concepts from cardinality minimization to those of rank minimization. We also discuss several algorithmic approaches to solving the norm minimization relaxations, and illustrate our results with numerical examples.

在本文中，我们将颜色图像插入作为纯季基矩阵完成问题。在文献中，季节矩阵完成的理论保证并不确定。我们的主要目的是提出一个新的最小化问题，并将核标准和三个通道之间的二次损失相结合。为了填补理论空缺，我们获得了在干净和损坏的政权中绑定的错误，这依赖于四元素矩阵的一些新结果。在强大的完成中考虑了一般的高斯噪音，所有观察都被损坏。由于界限的动机，我们建议通过二次损失中的跨通道重量来处理不平衡或相关的噪声，这是重新平衡噪声水平或消除噪声相关性的主要目的。提供了有关合成和颜色图像数据的广泛实验结果，以确认和证明我们的理论发现。

张量分解是从多维非负数据中提取物理有意义的潜在因素的强大工具，并且对诸如图像处理，机器学习和计算机视觉等各个领域的兴趣越来越多。在本文中，我们提出了一种稀疏的非负塔克分解和完成方法，用于在嘈杂的观察结果下恢复潜在的非负数据。在这里，基本的非负数据张量分解为核心张量，几个因子矩阵，所有条目均为无负，并且因子矩阵稀疏。损失函数是由嘈杂观测值的最大似然估计得出的，并且使用$ \ ell_0 $ norm来增强因子矩阵的稀疏性。我们在通用噪声场景下建立了拟议模型的估计器的误差结合，然后将其指定为具有加性高斯噪声，加法拉普拉斯噪声和泊松观测的观测值。我们的理论结果比现有基于张量或基于矩阵的方法更好。此外，最小值的下限显示与对数因子的衍生上限相匹配。合成数据集和现实世界数据集的数值示例证明了提出的非负张量数据完成方法的优越性。

We investigate the problem of recovering a partially observed high-rank matrix whose columns obey a nonlinear structure such as a union of subspaces, an algebraic variety or grouped in clusters. The recovery problem is formulated as the rank minimization of a nonlinear feature map applied to the original matrix, which is then further approximated by a constrained non-convex optimization problem involving the Grassmann manifold. We propose two sets of algorithms, one arising from Riemannian optimization and the other as an alternating minimization scheme, both of which include first- and second-order variants. Both sets of algorithms have theoretical guarantees. In particular, for the alternating minimization, we establish global convergence and worst-case complexity bounds. Additionally, using the Kurdyka-Lojasiewicz property, we show that the alternating minimization converges to a unique limit point. We provide extensive numerical results for the recovery of union of subspaces and clustering under entry sampling and dense Gaussian sampling. Our methods are competitive with existing approaches and, in particular, high accuracy is achieved in the recovery using Riemannian second-order methods.

诸如压缩感测，图像恢复，矩阵/张恢复和非负矩阵分子等信号处理和机器学习中的许多近期问题可以作为约束优化。预计的梯度下降是一种解决如此约束优化问题的简单且有效的方法。本地收敛分析将我们对解决方案附近的渐近行为的理解，与全球收敛分析相比，收敛率的较小界限提供了较小的界限。然而，本地保证通常出现在机器学习和信号处理的特定问题领域。此稿件在约束最小二乘范围内，对投影梯度下降的局部收敛性分析提供了统一的框架。该建议的分析提供了枢转局部收敛性的见解，例如线性收敛的条件，收敛区域，精确的渐近收敛速率，以及达到一定程度的准确度所需的迭代次数的界限。为了证明所提出的方法的适用性，我们介绍了PGD的收敛分析的配方，并通过在四个基本问题上的配方的开始延迟应用来证明它，即线性约束最小二乘，稀疏恢复，最小二乘法使用单位规范约束和矩阵完成。

本文提出了弗兰克 - 沃尔夫（FW）的新变种​​，称为$ k $ fw。标准FW遭受缓慢的收敛性：迭代通常是Zig-zag作为更新方向振荡约束集的极端点。新变种，$ k $ fw，通过在每次迭代中使用两个更强的子问题oracelles克服了这个问题。第一个是$ k $线性优化Oracle（$ k $ loo），计算$ k $最新的更新方向（而不是一个）。第二个是$ k $方向搜索（$ k $ ds），最大限度地减少由$ k $最新更新方向和之前迭代表示的约束组的目标。当问题解决方案承认稀疏表示时，奥克斯都易于计算，而且$ k $ FW会迅速收敛，以便平滑凸起目标和几个有趣的约束集：$ k $ fw实现有限$ \ frac {4l_f ^ 3d ^} { \ Gamma \ Delta ^ 2} $融合在多台和集团规范球上，以及光谱和核规范球上的线性收敛。数值实验验证了$ k $ fw的有效性，并展示了现有方法的数量级加速。

具有转换学习的非负矩阵分解（TL-NMF）是最近的一个想法，其旨在学习适合NMF的数据表示。在这项工作中，我们将TL-NMF与古典矩阵关节 - 对角化（JD）问题相关联。我们展示，当数据实现的数量足够大时，TL-NMF可以由作为JD + NMF称为JD + NMF的两步接近 - 通过JD在NMF计算之前估计变换。相比之下，我们发现，当数据实现的数量有限时，不仅是JD + NMF不等于TL-NMF，但TL-NMF的固有低级约束结果是学习有意义的基本成分转变为NMF。

监督字典学习（SDL）是一种经典的机器学习方法，同时寻求特征提取和分类任务，不一定是先验的目标。 SDL的目的是学习类歧视性词典，这是一组潜在特征向量，可以很好地解释特征以及观察到的数据的标签。在本文中，我们提供了SDL的系统研究，包括SDL的理论，算法和应用。首先，我们提供了一个新颖的框架，该框架将“提升” SDL作为组合因子空间中的凸问题，并提出了一种低级别的投影梯度下降算法，该算法将指数成倍收敛于目标的全局最小化器。我们还制定了SDL的生成模型，并根据高参数制度提供真实参数的全局估计保证。其次，我们被视为一个非convex约束优化问题，我们为SDL提供了有效的块坐标下降算法，该算法可以保证在$ O（\ varepsilon^{ - 1}（\ log）中找到$ \ varepsilon $ - 定位点（\ varepsilon \ varepsilon^{ - 1}）^{2}）$ iterations。对于相应的生成模型，我们为受约束和正则化的最大似然估计问题建立了一种新型的非反应局部一致性结果，这可能是独立的。第三，我们将SDL应用于监督主题建模和胸部X射线图像中的肺炎检测中，以进行不平衡的文档分类。我们还提供了模拟研究，以证明当最佳的重建性和最佳判别词典之间存在差异时，SDL变得更加有效。

最佳运输（OT）自然地出现在广泛的机器学习应用中，但可能经常成为计算瓶颈。最近，一行作品建议大致通过在低秩子空间中搜索\ emph {transport计划}来解决OT。然而，最佳运输计划通常不是低秩，这往往会产生大的近似误差。例如，当存在Monge的\ EMPH {Transport Map}时，运输计划是完整的排名。本文涉及具有足够精度和效率的OT距离的计算。提出了一种用于OT的新颖近似，其中运输计划可以分解成低级矩阵和稀疏矩阵的总和。理论上我们分析近似误差。然后设计增强拉格朗日方法以有效地计算运输计划。

低级和非平滑矩阵优化问题捕获了统计和机器学习中的许多基本任务。尽管近年来在开发\ textIt {平滑}低级优化问题的有效方法方面取得了重大进展，这些问题避免了保持高级矩阵和计算昂贵的高级SVD，但不平滑问题的进步的步伐缓慢。在本文中，我们考虑了针对此类问题的标准凸放松。主要是，我们证明，在\ textit {严格的互补性}条件下，在相对温和的假设下，非平滑目标可以写成最大的光滑功能，近似于两个流行的\ textit {mirriry-prox}方法的变体： \ textIt {外部方法}和带有\ textIt {矩阵启用梯度更新}的镜像 - prox，当用“温暖启动”初始化时，将速率$ o（1/t）$的最佳解决方案收集到最佳解决方案，同时仅需要两个\ textIt {low-rank} svds每迭代。此外，对于外部方法，我们还考虑了严格互补性的放松版本，该版本在所需的SVD等级与我们需要初始化该方法的球的半径之间取决于权衡。我们通过几个非平滑级矩阵恢复任务的经验实验来支持我们的理论结果，这既证明了严格的互补性假设的合理性，又证明了我们所提出的低级镜像 - 镜像变体的有效收敛。

我们研究了估计多元高斯分布中的精度矩阵的问题，其中所有部分相关性都是非负面的，也称为多变量完全阳性的顺序阳性（$ \ mathrm {mtp} _2 $）。近年来，这种模型得到了重大关注，主要是由于有趣的性质，例如，无论底层尺寸如何，最大似然估计值都存在于两个观察。我们将此问题作为加权$ \ ell_1 $ -norm正常化高斯的最大似然估计下$ \ mathrm {mtp} _2 $约束。在此方向上，我们提出了一种新颖的预计牛顿样算法，该算法包含精心设计的近似牛顿方向，这导致我们具有与一阶方法相同的计算和内存成本的算法。我们证明提出的预计牛顿样算法会聚到问题的最小值。从理论和实验中，我们进一步展示了我们使用加权$ \ ell_1 $ -norm的制剂的最小化器能够正确地恢复基础精密矩阵的支持，而无需在$ \ ell_1 $ -norm中存在不连贯状态方法。涉及合成和实世界数据的实验表明，我们所提出的算法从计算时间透视比最先进的方法显着更有效。最后，我们在金融时序数据中应用我们的方法，这些数据对于显示积极依赖性，在那里我们在学习金融网络上的模块间值方面观察到显着性能。

基于稀疏的代表的分类（SRC）通过将识别问题作为简单的线性回归问题铸造了很多关注。然而，SRC方法仍然仅限于每类别的足够标记的样本，不充分使用未标记的样本，以及表示的不稳定性。为了解决这些问题，提出了一种未标记的数据驱动的逆投影伪全空间表示的基于空间表示的分类模型，具有低级稀疏约束。所提出的模型旨在挖掘所有可用数据的隐藏语义信息和内在结构信息，这适用于少量标记的样本和标记样本与正面识别中的未标记样本问题之间的比例不平衡。引入了混合的高斯Seidel和Jacobian Admm算法来解决模型。分析了模型的收敛性，表示能力和稳定性。在三个公共数据集上的实验表明，所提出的LR-S-PFSRC模型达到稳定的结果，特别是对于样品的比例不平衡。

Low-rank matrix approximations, such as the truncated singular value decomposition and the rank-revealing QR decomposition, play a central role in data analysis and scientific computing. This work surveys and extends recent research which demonstrates that randomization offers a powerful tool for performing low-rank matrix approximation. These techniques exploit modern computational architectures more fully than classical methods and open the possibility of dealing with truly massive data sets.This paper presents a modular framework for constructing randomized algorithms that compute partial matrix decompositions. These methods use random sampling to identify a subspace that captures most of the action of a matrix. The input matrix is then compressed-either explicitly or implicitly-to this subspace, and the reduced matrix is manipulated deterministically to obtain the desired low-rank factorization. In many cases, this approach beats its classical competitors in terms of accuracy, speed, and robustness. These claims are supported by extensive numerical experiments and a detailed error analysis.The specific benefits of randomized techniques depend on the computational environment. Consider the model problem of finding the k dominant components of the singular value decomposition of an m × n matrix. (i) For a dense input matrix, randomized algorithms require O(mn log(k)) floating-point operations (flops) in contrast with O(mnk) for classical algorithms. (ii) For a sparse input matrix, the flop count matches classical Krylov subspace methods, but the randomized approach is more robust and can easily be reorganized to exploit multi-processor architectures. (iii) For a matrix that is too large to fit in fast memory, the randomized techniques require only a constant number of passes over the data, as opposed to O(k) passes for classical algorithms. In fact, it is sometimes possible to perform matrix approximation with a single pass over the data.

This paper is about a curious phenomenon. Suppose we have a data matrix, which is the superposition of a low-rank component and a sparse component. Can we recover each component individually? We prove that under some suitable assumptions, it is possible to recover both the low-rank and the sparse components exactly by solving a very convenient convex program called Principal Component Pursuit; among all feasible decompositions, simply minimize a weighted combination of the nuclear norm and of the 1 norm. This suggests the possibility of a principled approach to robust principal component analysis since our methodology and results assert that one can recover the principal components of a data matrix even though a positive fraction of its entries are arbitrarily corrupted. This extends to the situation where a fraction of the entries are missing as well. We discuss an algorithm for solving this optimization problem, and present applications in the area of video surveillance, where our methodology allows for the detection of objects in a cluttered background, and in the area of face recognition, where it offers a principled way of removing shadows and specularities in images of faces.

最近，优化衍生的学习（ODL）吸引了学习和视觉领域的关注，该学习和视觉领域从优化的角度设计了学习模型。但是，以前的ODL方法将训练和超训练程序视为两个分离的阶段，这意味着在训练过程中必须固定超训练变量，因此也不可能同时获得训练和超级培训的收敛性训练变量。在这项工作中，我们将基于定点迭代的广义Krasnoselkii-Mann（GKM）计划设计为我们的基本ODL模块，该模块将现有的ODL方法统一为特殊情况。在GKM方案下，构建了双级元优化（BMO）算法框架，以共同解决最佳训练和超训练变量。我们严格地证明了训练定点迭代的基本关节融合以及优化超训练的超训练的过程，无论是在近似质量方面还是在固定分析上。实验证明了BMO在稀疏编码和现实世界中的竞争性能的效率，例如图像反卷积和降雨的删除。

在线张量分解（OTF）是一种从流媒体多模态数据学习低维解释特征的基本工具。虽然最近已经调查了OTF的各种算法和理论方面，但仍然甚至缺乏任何不连贯或稀疏假设的客观函数的静止点的一般会聚保证仍然缺乏仍然缺乏缺乏。案件。在这项工作中，我们介绍了一种新颖的算法，该算法从一般约束下的给定的张力值数据流中学习了CANDECOMP / PARAFAC（CP），包括诱导学习CP的解释性的非承诺约束。我们证明我们的算法几乎肯定会收敛到目标函数的一组静止点，在该假设下，数据张集的序列由底层马尔可夫链产生。我们的环境涵盖了古典的i.i.d.案例以及广泛的应用程序上下文，包括由独立或MCMC采样生成的数据流。我们的结果缩小了OTF和在线矩阵分解在全局融合分析中的OTF和在线矩阵分解之间的差距\ Commhl {对于CP - 分解}。实验，我们表明我们的算法比合成和实际数据的非负张量分解任务的标准算法更快地收敛得多。此外，我们通过图像，视频和时间序列数据展示了我们算法对来自图像，视频和时间序列数据的多样化示例的实用性，示出了通过以多种方式利用张量结构来利用张量结构，如何从相同的张量数据中学习定性不同的CP字典。 。

在本文中，我们提出了一个算法框架，称为乘数的惯性交替方向方法（IADMM），用于求解与线性约束线性约束的一类非convex非conmooth多块复合优化问题。我们的框架采用了一般最小化 - 更大化（MM）原理来更新每个变量块，从而不仅统一了先前在MM步骤中使用特定替代功能的AMDM的收敛分析，还导致新的有效ADMM方案。据我们所知，在非convex非平滑设置中，ADMM与MM原理结合使用，以更新每个变量块，而ADMM与\ emph {Primal变量的惯性术语结合在一起}尚未在文献中研究。在标准假设下，我们证明了生成的迭代序列的后续收敛和全局收敛性。我们说明了IADMM对一类非凸低级别表示问题的有效性。

Nonnegative Tucker Factorization (NTF) minimizes the euclidean distance or Kullback-Leibler divergence between the original data and its low-rank approximation which often suffers from grossly corruptions or outliers and the neglect of manifold structures of data. In particular, NTF suffers from rotational ambiguity, whose solutions with and without rotation transformations are equally in the sense of yielding the maximum likelihood. In this paper, we propose three Robust Manifold NTF algorithms to handle outliers by incorporating structural knowledge about the outliers. They first applies a half-quadratic optimization algorithm to transform the problem into a general weighted NTF where the weights are influenced by the outliers. Then, we introduce the correntropy induced metric, Huber function and Cauchy function for weights respectively, to handle the outliers. Finally, we introduce a manifold regularization to overcome the rotational ambiguity of NTF. We have compared the proposed method with a number of representative references covering major branches of NTF on a variety of real-world image databases. Experimental results illustrate the effectiveness of the proposed method under two evaluation metrics (accuracy and nmi).