1,811 research outputs found
Characterization of four-qubit states via Bell inequalities
A set of Bell inequalities classifying the quantum entanglement of four-qubit
states is presented. These inequalities involve only two measurement settings
per observer and can characterize fully separable, bi-separable and
tri-separable quantum states. In addition, a quadratic inequality of the Bell
operators for four-qubit systems is derived
THE RELATIONSHIP BETWEEN SHOT PUT TECHNIQUE AND MECHANICAL ENERGY OUTPUT OF CHINESE FEMALE SHOT-PUTT ATHLETES
The purpose of this study was to examine the relationship between the shot-putt technique and the energy output in Chinese female shot-putt athletes. Three-dimensional photogrammetry and a video analysis system were used to study the shot-put technique from the perspective of the body’s output of mechanical energy. It was found that, during the sliding phase, the main energy output was the kinetic energy of translation. During the transitional phase, the body expends the least energy in delivery of the shot. In the beginning of the push-off phase, the maximum amount of mechanical energy and kinetic energy was used. At the end of the push-off phase the energy output decreased.
Otherwise, the relationship between the energy output with the shot putt result and technique indicated that the trunk’s energy output were closely correlated with the shot putt result. Knowledge of the trunk’s movement is of great importance to the shot-put technique
Co-Salient Object Detection with Co-Representation Purification
Co-salient object detection (Co-SOD) aims at discovering the common objects
in a group of relevant images. Mining a co-representation is essential for
locating co-salient objects. Unfortunately, the current Co-SOD method does not
pay enough attention that the information not related to the co-salient object
is included in the co-representation. Such irrelevant information in the
co-representation interferes with its locating of co-salient objects. In this
paper, we propose a Co-Representation Purification (CoRP) method aiming at
searching noise-free co-representation. We search a few pixel-wise embeddings
probably belonging to co-salient regions. These embeddings constitute our
co-representation and guide our prediction. For obtaining purer
co-representation, we use the prediction to iteratively reduce irrelevant
embeddings in our co-representation. Experiments on three datasets demonstrate
that our CoRP achieves state-of-the-art performances on the benchmark datasets.
Our source code is available at https://github.com/ZZY816/CoRP.Comment: Accepted by TPAMI 202
Zoom-VQA: Patches, Frames and Clips Integration for Video Quality Assessment
Video quality assessment (VQA) aims to simulate the human perception of video
quality, which is influenced by factors ranging from low-level color and
texture details to high-level semantic content. To effectively model these
complicated quality-related factors, in this paper, we decompose video into
three levels (\ie, patch level, frame level, and clip level), and propose a
novel Zoom-VQA architecture to perceive spatio-temporal features at different
levels. It integrates three components: patch attention module, frame pyramid
alignment, and clip ensemble strategy, respectively for capturing
region-of-interest in the spatial dimension, multi-level information at
different feature levels, and distortions distributed over the temporal
dimension. Owing to the comprehensive design, Zoom-VQA obtains state-of-the-art
results on four VQA benchmarks and achieves 2nd place in the NTIRE 2023 VQA
challenge. Notably, Zoom-VQA has outperformed the previous best results on two
subsets of LSVQ, achieving 0.8860 (+1.0%) and 0.7985 (+1.9%) of SRCC on the
respective subsets. Adequate ablation studies further verify the effectiveness
of each component. Codes and models are released in
https://github.com/k-zha14/Zoom-VQA.Comment: Accepted by CVPR 2023 Worksho
Efficient and convenient synthesis of symmetrical carboxylic anhydrides from carboxylic acids with sulfated zirconia by phase transfer catalysis
An efficient and convenient procedure for the synthesis of symmetrical carboxylic anhydrides from carboxylic acids with sulfated zirconia by PEG-1000 phase transfer catalysis has been developed. The reactions proceeded under mild and solvent-free conditions to provide the carboxylic anhydrides in good to excellent yields. The product can be isolated by a simple extraction with organic solvent, and the catalyst system can be recycled or reused without any significant loss of catalytic activity.KEY WORDS: Carboxylic anhydrides, Carboxylic acids, SO42-/ZrO2, Phase transfer catalysis Bull. Chem. Soc. Ethiop. 2011, 25(2), 255-262
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