728 research outputs found
A combinatorial criterion for k-separability of multipartite Dicke states
We derive a combinatorial criterion for detecting k-separability of N-partite
Dicke states. The criterion is efficiently computable and implementable without
full state tomography. We give examples in which the criterion succeeds, where
known criteria fail
ASCON: Anatomy-aware Supervised Contrastive Learning Framework for Low-dose CT Denoising
While various deep learning methods have been proposed for low-dose computed
tomography (CT) denoising, most of them leverage the normal-dose CT images as
the ground-truth to supervise the denoising process. These methods typically
ignore the inherent correlation within a single CT image, especially the
anatomical semantics of human tissues, and lack the interpretability on the
denoising process. In this paper, we propose a novel Anatomy-aware Supervised
CONtrastive learning framework, termed ASCON, which can explore the anatomical
semantics for low-dose CT denoising while providing anatomical
interpretability. The proposed ASCON consists of two novel designs: an
efficient self-attention-based U-Net (ESAU-Net) and a multi-scale anatomical
contrastive network (MAC-Net). First, to better capture global-local
interactions and adapt to the high-resolution input, an efficient ESAU-Net is
introduced by using a channel-wise self-attention mechanism. Second, MAC-Net
incorporates a patch-wise non-contrastive module to capture inherent anatomical
information and a pixel-wise contrastive module to maintain intrinsic
anatomical consistency. Extensive experimental results on two public low-dose
CT denoising datasets demonstrate superior performance of ASCON over
state-of-the-art models. Remarkably, our ASCON provides anatomical
interpretability for low-dose CT denoising for the first time. Source code is
available at https://github.com/hao1635/ASCON.Comment: MICCAI 202
In-plane vibration modal analysis of heavy-loaded radial tire with a larger flat ratio
Experimental modal analysis, dynamic modeling and parameter identification is employed to investigate the in-plane vibration modal characteristic of a heavy-loaded radial tire with a larger flat ratio. In-plane vibration characteristic of heavy-loaded radial tire is modeled as flexible beam on modified elastic foundation model and flexible tread and distributed sidewall are respectively modeled as the Euler beam and distributed mass element with sectional stiffness. Analytic relationship between the modal resonant frequency and the structural parameters is solved and derived with modal expansion method. The in-plane coupling modal between the flexible tread and sidewall is investigated experimentally. The unknown structural parameters are identified by the genetic algorithm based on the experimental and analytical modal parameter. The higher order modal frequency is predicted with the identified structural parameters and the influence of structural parameters on the modal parameters is compared. Experimental and theoretical result shows that: the experimental modal analysis and theoretical modeling method with the coupling feature of flexible tread, distributed sidewall and rim can accurately characterize the in-plane vibration feature of heavy-loaded radial tire within the frequency band of 300Â Hz, compared with the method which only considers the flexible feature of tread and is limited to 180Â Hz
In-plane vibration analysis of heavy-loaded radial tire utilizing the rigid-elastic coupling tire model with normal damping
Theoretical modeling, parameters identification and vibration characteristic of heavy-loaded radial tire is investigated with rigid-elastic coupling model with normal damping. The normal damping, including structural damping of flexible carcass and proportion damping of distributed sidewall element is added to enrich the flexible beam on modified elastic foundation tire model. The rigid-elastic coupling tire model with normal damping is investigated and derived with finite difference method. The mass, stiffness and damping matrixes of the proposed tire model are analytically related with the structural and geometrical parameters of heavy-loaded radial tire. Taking the error between the analytical and experimental transfer function as the object value, Genetic Algorithm (GA) is utilized to identify the damping coefficients of flexible carcass and distributed sidewall element. The influence of modal order and tire damping parameters on the in-plane transfer function is discussed. The theoretical and experimental results show that the rigid-elastic coupling tire model with normal damping can achieve the sectional feature of in-plane transfer function resulting from the coupling characteristic between the flexible carcass and distributed sidewall element within the frequency band of 300 Hz
Article Remote Sensing of Agro-droughts in Guangdong Province of China Using MODIS Satellite Data
sensor
Anchor Sampling for Federated Learning with Partial Client Participation
Compared with full client participation, partial client participation is a
more practical scenario in federated learning, but it may amplify some
challenges in federated learning, such as data heterogeneity. The lack of
inactive clients' updates in partial client participation makes it more likely
for the model aggregation to deviate from the aggregation based on full client
participation. Training with large batches on individual clients is proposed to
address data heterogeneity in general, but their effectiveness under partial
client participation is not clear. Motivated by these challenges, we propose to
develop a novel federated learning framework, referred to as FedAMD, for
partial client participation. The core idea is anchor sampling, which separates
partial participants into anchor and miner groups. Each client in the anchor
group aims at the local bullseye with the gradient computation using a large
batch. Guided by the bullseyes, clients in the miner group steer multiple
near-optimal local updates using small batches and update the global model. By
integrating the results of the two groups, FedAMD is able to accelerate the
training process and improve the model performance. Measured by
-approximation and compared to the state-of-the-art methods, FedAMD
achieves the convergence by up to fewer communication rounds
under non-convex objectives. Empirical studies on real-world datasets validate
the effectiveness of FedAMD and demonstrate the superiority of the proposed
algorithm: Not only does it considerably save computation and communication
costs, but also the test accuracy significantly improves.Comment: ICML 202
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