1,326 research outputs found
Robust Face Recognition With Kernelized Locality-Sensitive Group Sparsity Representation
In this paper, a novel joint sparse representation method is proposed for robust face recognition. We embed both group sparsity and kernelized locality-sensitive constraints into the framework of sparse representation. The group sparsity constraint is designed to utilize the grouped structure information in the training data. The local similarity between test and training data is measured in the kernel space instead of the Euclidian space. As a result, the embedded nonlinear information can be effectively captured, leading to a more discriminative representation. We show that, by integrating the kernelized local-sensitivity constraint and the group sparsity constraint, the embedded structure information can be better explored, and significant performance improvement can be achieved. On the one hand, experiments on the ORL, AR, extended Yale B, and LFW data sets verify the superiority of our method. On the other hand, experiments on two unconstrained data sets, the LFW and the IJB-A, show that the utilization of sparsity can improve recognition performance, especially on the data sets with large pose variation
Anomaly Discovery and Arbitrage Trading
Our model of anomaly discovery has implications for both asset prices and arbitrageurs\u27 trading. Consistent with existing evidence, the discovery of an anomaly reduces its magnitude. Our evidence based on 99 anomalies is consistent with new predictions that the discovery of an anomaly reduces the correlation between the returns its deciles 1 and 10, leading to diversification benefits for passive investors. These effects become linked to the aggregate trading of hedge funds only after discovery. Hedge funds increase (reverse) their positions in exploiting anomalies when their aggregate wealth increases (decreases), further suggesting that these discovery effects operate through arbitrage trading
CiT-Net: Convolutional Neural Networks Hand in Hand with Vision Transformers for Medical Image Segmentation
The hybrid architecture of convolutional neural networks (CNNs) and
Transformer are very popular for medical image segmentation. However, it
suffers from two challenges. First, although a CNNs branch can capture the
local image features using vanilla convolution, it cannot achieve adaptive
feature learning. Second, although a Transformer branch can capture the global
features, it ignores the channel and cross-dimensional self-attention,
resulting in a low segmentation accuracy on complex-content images. To address
these challenges, we propose a novel hybrid architecture of convolutional
neural networks hand in hand with vision Transformers (CiT-Net) for medical
image segmentation. Our network has two advantages. First, we design a dynamic
deformable convolution and apply it to the CNNs branch, which overcomes the
weak feature extraction ability due to fixed-size convolution kernels and the
stiff design of sharing kernel parameters among different inputs. Second, we
design a shifted-window adaptive complementary attention module and a compact
convolutional projection. We apply them to the Transformer branch to learn the
cross-dimensional long-term dependency for medical images. Experimental results
show that our CiT-Net provides better medical image segmentation results than
popular SOTA methods. Besides, our CiT-Net requires lower parameters and less
computational costs and does not rely on pre-training. The code is publicly
available at https://github.com/SR0920/CiT-Net
Structures and Anomalies of Water
Introduction of the principles of the asymmetrical, short-range O:H-O coupled
oscillater pair and the basic rule for water ice, which reconciles the
structure and anomalies of water ice.Comment: 20 pages. In Chines
Comparison of Cloud Base Height Derived from a Ground-Based Infrared Cloud Measurement and Two Ceilometers
The cloud base height (CBH) derived from the whole-sky infrared cloud-measuring system (WSIRCMS) and two ceilometers (Vaisala CL31 and CL51) from November 1, 2011, to June 12, 2012, at the Chinese Meteorological Administration (CMA) Beijing Observatory Station are analysed. Significant differences can be found by comparing the measurements of different instruments. More exactly, the cloud occurrence retrieved from CL31 is 3.8% higher than that from CL51, while WSIRCMS data shows 3.6% higher than ceilometers. More than 75.5% of the two ceilometersâ differences are within ±200âm and about 89.5% within ±500âm, while only 30.7% of the differences between WSIRCMS and ceilometers are within ±500âm and about 55.2% within ±1000âm. These differences may be caused by the measurement principles and CBH retrieval algorithm. A combination of a laser ceilometer and an infrared cloud instrument is recommended to improve the capability for determining cloud occurrence and retrieving CBHs
3-(1,3-DithioÂlan-2-ylÂidene)-1-phenylÂpyridine-2,4(1H,3H)-dione
The title compound, C14H11NO2S2, was synthesized by reaction of 2-(1,3-dithioÂlan-2-ylÂidene)-3-oxo-N-phenylÂbutanamide with N,NâČ-dimethylÂformamide dimethyl acetal in N,NâČ-dimethylÂformamide. The molÂecule exhibits a V-shaped conformation in the crystal, with a dihedral angle of 65.9â
(2)° between the benzene and pyridine rings. In the crystal. CâHâŻO and CâHâŻS interactions are observed. Two C atoms of the dithiolane ring are disordered with occupancies in the ratio 0.541â
(13)/0.459â
(13)
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