nils-herrmann/clean_scirepeval huggingface dataset:
Kernel-based storm tracking in radar data

The tracking of storm centres in radar data is of particular importance for short term weather prediction and specifically thunderstorm prediction. This paper presents a method to track storm centres in terrestrial radar images. Mean shift segmentation is used to outline storm centres and mean shift tracking to locate the storm in the consecutive images. Results demonstrate the ability of the method to deal with deformable objects such as storm centres. Moreover, the method is able to handle the splitting and merging of the convective cells.
Similarity learning on an explicit polynomial kernel feature map for person re-identification

In this paper, we address the person re-identification problem, discovering the correct matches for a probe person image from a set of gallery person images. We follow the learning-to-rank methodology and learn a similarity function to maximize the difference between the similarity scores of matched and unmatched images for a same person. We introduce at least three contributions to person re-identification. First, we present an explicit polynomial kernel feature map, which is capable of characterizing the similarity information of all pairs of patches between two images, called soft-patch-matching, instead of greedily keeping only the best matched patch, and thus more robust. Second, we introduce a mixture of linear similarity functions that is able to discover different soft-patch-matching patterns. Last, we introduce a negative semi-definite regularization over a subset of the weights in the similarity function, which is motivated by the connection between explicit polynomial kernel feature map and the Mahalanobis distance, as well as the sparsity constraint over the parameters to avoid over-fitting. Experimental results over three public benchmarks demonstrate the superiority of our approach.
Scalable k-NN graph construction for visual descriptors

The k-NN graph has played a central role in increasingly popular data-driven techniques for various learning and vision tasks; yet, finding an efficient and effective way to construct k-NN graphs remains a challenge, especially for large-scale high-dimensional data. In this paper, we propose a new approach to construct approximate k-NN graphs with emphasis in: efficiency and accuracy. We hierarchically and randomly divide the data points into subsets and build an exact neighborhood graph over each subset, achieving a base approximate neighborhood graph; we then repeat this process for several times to generate multiple neighborhood graphs, which are combined to yield a more accurate approximate neighborhood graph. Furthermore, we propose a neighborhood propagation scheme to further enhance the accuracy. We show both theoretical and empirical accuracy and efficiency of our approach to k-NN graph construction and demonstrate significant speed-up in dealing with large scale visual data.
A search strategy of UAV's automatic landing on ship in all weathe

A new scheme is proposed to realize Unmanned Aerial Vehicle's (UAV's) automatic landing on the ship precisely in all weather, which is based on the infrared cooperative object on ship's runway and the infrared computer vision in UAV. Firstly the UAV is guided to the neighborhood of landing position by SINS, and then the seamless spiral search strategy is applied to acquire the accurate position of ship in the navigation error. We establish the model of our searching strategy by Archimedes spiral based on the application characteristics of landing on ship and the parameters of the speed of UAV, the speed of the ship, the navigation error of SINS per hour, the whole time of flight, the minimum swerve radius of UAV, size of the ship, and the maximum Field of View (FOV) of camera lens. The experiments show that the proposed spiral search strategy can make UAV to find the ship reliably in the navigation error.
Optimized video scene segmentation

In this paper, we propose an optimized video scene segmentation approach with considering both content coherence and temporally contextual dissimilarity. First, a chain structure is constructed by connecting temporally adjacent shots to represent a video. Then the chain is partitioned such that the content within a chain segment is coherent enough and the contextual similarity of temporally adjacent chain segments is small enough. This task is formulated as a ratio function of content coherence and contextual similarity. Finally, we present an effective and efficient hierarchical chain partitioning approach to find the optimal scene segmentation. Experimental results on a set of home videos and feature movies demonstrate the superiority of the proposed approach over several existing key approaches.
Research on the frame structure of light-small optoelectronic stabilized platform assembled on UAV

Aiming at the loading condition requirements of UAV platform, this paper designs the structure of the light-small opto-electronic stabilized platform assembled on UAV. By analyzing the requirement of frame structure, function and parameters of the opto-electronic stabilized platform, the structure of two axis and three frames is chosen; the separated outer frame design is adopted, and then they are optimized. This can decrease the difficulty of the assembly greatly and improve the precision of the whole platform. Then, this paper builds the opto-electronic stabilized platform model and dynamical simulation on it.
A non-convex relaxation approach to sparse dictionary learning

Dictionary learning is a challenging theme in computer vision. The basic goal is to learn a sparse representation from an overcomplete basis set. Most existing approaches employ a convex relaxation scheme to tackle this challenge due to the strong ability of convexity in computation and theoretical analysis. In this paper we propose a non-convex online approach for dictionary learning. To achieve the sparseness, our approach treats a so-called minimax concave (MC) penalty as a nonconvex relaxation of the ℓ0 penalty. This treatment expects to obtain a more robust and sparse representation than existing convex approaches. In addition, we employ an online algorithm to adaptively learn the dictionary, which makes the non-convex formulation computationally feasible. Experimental results on the sparseness comparison and the applications in image denoising and image inpainting demonstrate that our approach is more effective and flexible.
Integration process and mechanism of agricultural industral chain and technology chain: A link model for the supply and demand sides of agricultural technology

In order to solve the low level of technology, high repetition rate, low rate of Conversion of technological achievements, and other similar problems in Chinese agricultural industry. This pape builds a link mechanism between the demand and supply sides of technology about Chinese agricultural industry. Different from previous studies, this paper narrows the scope of the integration of the agricultural industrial chain and technology chain into two-dimensional framework. Around the core of Technological innovation and the construction of modern agricultural technology chain, focused on the integration issues and relevant actors' behavior in agricultural industrial chain and the agricultural technology chain. This paper extends the existed integration theory of agricultural industry chain, builds the integration model, and the integration processes, mechanism of agricultural industry chain and technology chain were analyzed.
Optimized Cartesian K-Means

Product quantization-based approaches are effective to encode high-dimensional data points for approximate nearest neighbor search. The space is decomposed into a Cartesian product of low-dimensional subspaces, each of which generates a sub codebook. Data points are encoded as compact binary codes using these sub codebooks, and the distance between two data points can be approximated efficiently from their codes by the precomputed lookup tables. Traditionally, to encode a subvector of a data point in a subspace, only one sub codeword in the corresponding sub codebook is selected, which may impose strict restrictions on the search accuracy. In this paper, we propose a novel approach, named optimized cartesian K-means (ock-means), to better encode the data points for more accurate approximate nearest neighbor search. In ock-means, multiple sub codewords are used to encode the subvector of a data point in a subspace. Each sub codeword stems from different sub codebooks in each subspace, which are optimally generated with regards to the minimization of the distortion errors. The high-dimensional data point is then encoded as the concatenation of the indices of multiple sub codewords from all the subspaces. This can provide more flexibility and lower distortion errors than traditional methods. Experimental results on the standard real-life data sets demonstrate the superiority over state-of-the-art approaches for approximate nearest neighbor search.
DeepSaliency: Multi-Task Deep Neural Network Model for Salient Object Detection

A key problem in salient object detection is how to effectively model the semantic properties of salient objects in a data-driven manner. In this paper, we propose a multi-task deep saliency model based on a fully convolutional neural network with global input (whole raw images) and global output (whole saliency maps). In principle, the proposed saliency model takes a data-driven strategy for encoding the underlying saliency prior information, and then sets up a multi-task learning scheme for exploring the intrinsic correlations between saliency detection and semantic image segmentation. Through collaborative feature learning from such two correlated tasks, the shared fully convolutional layers produce effective features for object perception. Moreover, it is capable of capturing the semantic information on salient objects across different levels using the fully convolutional layers, which investigate the feature-sharing properties of salient object detection with a great reduction of feature redundancy. Finally, we present a graph Laplacian regularized nonlinear regression model for saliency refinement. Experimental results demonstrate the effectiveness of our approach in comparison with the state-of-the-art approaches.
Composite Quantization.

This paper studies the compact coding approach to approximate nearest neighbor search. We introduce a composite quantization framework. It uses the composition of several ($M$M) elements, each of which is selected from a different dictionary, to accurately approximate a $D$D-dimensional vector, thus yielding accurate search, and represents the data vector by a short code composed of the indices of the selected elements in the corresponding dictionaries. Our key contribution lies in introducing a near-orthogonality constraint, which makes the search efficiency is guaranteed as the cost of the distance computation is reduced to $O(M)$O(M) from $O(D)$O(D) through a distance table lookup scheme. The resulting approach is called near-orthogonal composite quantization. We theoretically justify the equivalence between near-orthogonal composite quantization and minimizing an upper bound of a function formed by jointly considering the quantization error and the search cost according to a generalized triangle inequality. We empirically show the efficacy of the proposed approach over several benchmark datasets. In addition, we demonstrate the superior performances in other three applications: combination with inverted multi-index, inner-product similarity search, and query compression for mobile search.
Salient object detection for searched web images via global saliency

In this paper, we deal with the problem of detecting the existence and the location of salient objects for thumbnail images on which most search engines usually perform visual analysis in order to handle web-scale images. Different from previous techniques, such as sliding window-based or segmentation-based schemes for detecting salient objects, we propose to use a learning approach, random forest in our solution. Our algorithm exploits global features from multiple saliency indicators to directly predict the existence and the position of the salient object. To validate our algorithm, we constructed a large image database collected from Bing image search, that contains hundreds of thousands of manually labeled web images. The experimental results using this new database and the resized MSRA database [16] demonstrate that our algorithm outperforms previous state-of-the-art methods.
Optimizing kd-trees for scalable visual descriptor indexing

In this paper, we attempt to scale up the kd-tree indexing methods for large-scale vision applications, e.g., indexing a large number of SIFT features and other types of visual descriptors. To this end, we propose an effective approach to generate near-optimal binary space partitioning and need low time cost to access the nodes in the query stage. First, we relax the coordinate-axis-alignment constraint in partition axis selection used in conventional kd-trees, and form a partition axis with the great variance by combining a few coordinate axes in a binary manner for each node, which yields better space partitioning and requires almost the same time cost to visit internal nodes during the query stage thanks to cheap projection operations. Then, we introduce a simple but very effective scheme to guarantee the partition axis of each internal node is orthogonal to or parallel with those of its ancestors, which leads to efficient distance computation between a query point and the cell associated with each node and yields fast priority search. Compared with the conventional kd-trees, our approach takes a little more tree construction time, but obtains much better nearest neighbor search performance. Experimental results on large scale local patch indexing and image search with tiny images show that our approach outperforms the state-of-the-art kd-tree based indexing methods.
Fast approximate k-means via cluster closures

K-means, a simple and effective clustering algorithm, is one of the most widely used algorithms in computer vision community. Traditional k-means is an iterative algorithm - in each iteration new cluster centers are computed and each data point is re-assigned to its nearest center. The cluster re-assignment step becomes prohibitively expensive when the number of data points and cluster centers are large. In this paper, we propose a novel approximate k-means algorithm to greatly reduce the computational complexity in the assignment step. Our approach is motivated by the observation that most active points changing their cluster assignments at each iteration are located on or near cluster boundaries. The idea is to efficiently identify those active points by pre-assembling the data into groups of neighboring points using multiple random spatial partition trees, and to use the neighborhood information to construct a closure for each cluster, in such a way only a small number of cluster candidates need to be considered when assigning a data point to its nearest cluster. Using complexity analysis, real data clustering, and applications to image retrieval, we show that our approach out-performs state-of-the-art approximate k-means algorithms in terms of clustering quality and efficiency.
Joint Affinity Propagation for Multiple View Segmentation

A joint segmentation is a simultaneous segmentation of registered 2D images and 3D points reconstructed from the multiple view images. It is fundamental in structuring the data for subsequent modeling applications. In this paper, we treat this joint segmentation as a weighted graph labeling problem. First, we construct a 3D graph for the joint 3D and 2D points using a joint similarity measure. Then, we propose a hierarchical sparse affinity propagation algorithm to automatically and jointly segment 2D images and group 3D points. Third, a semi-supervised affinity propagation algorithm is proposed to refine the automatic results with the user assistance. Finally, intensive experiments demonstrate the effectiveness of the proposed approaches.
Low-rank SIFT: An affine invariant feature for place recognition

In this paper, we study the problem of recognizing man-made objects and present a novel affine-invariant feature, Low-rank SIFT, which exploits the regular appearance property in man-made objects. The proposed feature achieves full affine invariance without needing to simulate over affine parameter space. We rectify local patches by converting them to their low-rank forms to achieve skew invariance, and perform the way similar to conventional SIFT to resolve rotation, translation and scaling ambiguity. The main contributions lie in two-fold: our method seeks to leverage low-rank prior to estimate affine parameters for local patches directly and we propose a fast algorithm to compute such parameters by introducing the Low-rank Integral Map. Besides, we describe a pipeline of constructing a geotagged building database from the ground up. We demonstrate the effectiveness of our approach in the application to place recognition.
Co-saliency detection via looking deep and wide

With the goal of effectively identifying common and salient objects in a group of relevant images, co-saliency detection has become essential for many applications such as video foreground extraction, surveillance, image retrieval, and image annotation. In this paper, we propose a unified co-saliency detection framework by introducing two novel insights: 1) looking deep to transfer higher-level representations by using the convolutional neural network with additional adaptive layers could better reflect the properties of the co-salient objects, especially their consistency among the image group; 2) looking wide to take advantage of the visually similar neighbors beyond a certain image group could effectively suppress the influence of the common background regions when formulating the intra-group consistency. In the proposed framework, the wide and deep information are explored for the object proposal windows extracted in each image, and the co-saliency scores are calculated by integrating the intra-image contrast and intra-group consistency via a principled Bayesian formulation. Finally the window-level co-saliency scores are converted to the superpixel-level co-saliency maps through a foreground region agreement strategy. Comprehensive experiments on two benchmark datasets have demonstrated the consistent performance gain of the proposed approach.
Ordinal Constraint Binary Coding for Approximate Nearest Neighbor Search

Binary code learning, <italic>a.k.a.</italic> hashing, has been successfully applied to the approximate nearest neighbor search in large-scale image collections. The key challenge lies in reducing the quantization error from the original real-valued feature space to a discrete Hamming space. Recent advances in unsupervised hashing advocate the preservation of ranking information, which is achieved by constraining the binary code learning to be correlated with pairwise similarity. However, few unsupervised methods consider the preservation of <italic>ordinal relations</italic> in the learning process, which serves as a more basic cue to learn optimal binary codes. In this paper, we propose a novel hashing scheme, termed Ordinal Constraint Hashing (OCH), which embeds the ordinal relation among data points to preserve ranking into binary codes. The core idea is to construct an ordinal graph via tensor product, and then train the hash function over this graph to preserve the permutation relations among data points in the Hamming space. Subsequently, an in-depth acceleration scheme, termed Ordinal Constraint Projection (OCP), is introduced, which approximates the <inline-formula><tex-math notation="LaTeX">$n$</tex-math><alternatives><inline-graphic xlink:href="ji-ieq1-2819978.gif"/></alternatives></inline-formula>-pair ordinal graph by <inline-formula><tex-math notation="LaTeX">$L$</tex-math><alternatives><inline-graphic xlink:href="ji-ieq2-2819978.gif"/></alternatives></inline-formula>-pair anchor-based ordinal graph, and reduce the corresponding complexity from <inline-formula><tex-math notation="LaTeX">$O(n^4)$</tex-math><alternatives><inline-graphic xlink:href="ji-ieq3-2819978.gif"/></alternatives></inline-formula> to <inline-formula><tex-math notation="LaTeX">$O(L^3)$</tex-math><alternatives><inline-graphic xlink:href="ji-ieq4-2819978.gif"/></alternatives></inline-formula> (<inline-formula><tex-math notation="LaTeX">$L\ll n$</tex-math><alternatives><inline-graphic xlink:href="ji-ieq5-2819978.gif"/></alternatives></inline-formula>). Finally, to make the optimization tractable, we further relax the discrete constrains and design a customized stochastic gradient decent algorithm on the Stiefel manifold. Experimental results on serval large-scale benchmarks demonstrate that the proposed OCH method can achieve superior performance over the state-of-the-art approaches.
Deep kinship verification

To improve the performance of kinship verification, we propose a novel deep kinship verification (DKV) model by integrating excellent deep learning architecture into metric learning. Unlike most existing shallow models based on metric learning for kinship verification, we employ a deep learning model followed by a metric learning formulation to select nonlinear features, which can find the appropriate project space to ensure the margin of negative sample pairs (i.e. parent and child without kinship relation) as large as possible and the margin of positive sample pairs (i.e. parent and child with kinship relation) as small as possible. Experimental results show that our method achieves satisfactory performance on two widely-used benchmarks, i.e. KFW-I and KFW-II.
Weakly Supervised Metric Learning for Traffic Sign Recognition in a LIDAR-Equipped Vehicle

We address the problem of traffic sign recognition in a light detection and ranging (LIDAR)-equipped vehicle. With the help of 3-D LIDAR points, the 2-D multiview sign images will be easily detected from the captured images of street signs. After detection, the sign recognition problem is formulated as a multiview object recognition task. We develop a metric-learning-based template matching approach for this task and learn a distance metric between the captured images and the corresponding sign templates. For each sign, recognition is done via soft voting by the recognition results of its corresponding multiview images. We propose a latent structural support vector machine (SVM)-based weakly supervised metric learning (WSMLR) method to learn the metric and a reliability classifier. The reliability classifier is used to determine each image's reliability, which serves as each image's weight in both the learning and soft voting procedure. We evaluate the proposed method for multiview traffic sign recognition on a multiview traffic sign data set with 112 categories and observe very encouraging results compared with other state-of-the-art methods. In addition, the method can be customized to solve the single-view sign recognition. The performance of our method for single-view sign recognition is tested on two public data sets, showing that our method is comparable with other competitive ones.