212 research outputs found
Learn from Unpaired Data for Image Restoration: A Variational Bayes Approach
Collecting paired training data is difficult in practice, but the unpaired
samples broadly exist. Current approaches aim at generating synthesized
training data from the unpaired samples by exploring the relationship between
the corrupted and clean data. This work proposes LUD-VAE, a deep generative
method to learn the joint probability density function from data sampled from
marginal distributions. Our approach is based on a carefully designed
probabilistic graphical model in which the clean and corrupted data domains are
conditionally independent. Using variational inference, we maximize the
evidence lower bound (ELBO) to estimate the joint probability density function.
Furthermore, we show that the ELBO is computable without paired samples under
the inference invariant assumption. This property provides the mathematical
rationale of our approach in the unpaired setting. Finally, we apply our method
to real-world image denoising and super-resolution tasks and train the models
using the synthetic data generated by the LUD-VAE. Experimental results
validate the advantages of our method over other learnable approaches
Flare-Aware Cross-modal Enhancement Network for Multi-spectral Vehicle Re-identification
Multi-spectral vehicle re-identification aims to address the challenge of
identifying vehicles in complex lighting conditions by incorporating
complementary visible and infrared information. However, in harsh environments,
the discriminative cues in RGB and NIR modalities are often lost due to strong
flares from vehicle lamps or sunlight, and existing multi-modal fusion methods
are limited in their ability to recover these important cues. To address this
problem, we propose a Flare-Aware Cross-modal Enhancement Network that
adaptively restores flare-corrupted RGB and NIR features with guidance from the
flare-immunized thermal infrared spectrum. First, to reduce the influence of
locally degraded appearance due to intense flare, we propose a Mutual Flare
Mask Prediction module to jointly obtain flare-corrupted masks in RGB and NIR
modalities in a self-supervised manner. Second, to use the flare-immunized TI
information to enhance the masked RGB and NIR, we propose a Flare-Aware
Cross-modal Enhancement module that adaptively guides feature extraction of
masked RGB and NIR spectra with prior flare-immunized knowledge from the TI
spectrum. Third, to extract common informative semantic information from RGB
and NIR, we propose an Inter-modality Consistency loss that enforces semantic
consistency between the two modalities. Finally, to evaluate the proposed
FACENet in handling intense flare, we introduce a new multi-spectral vehicle
re-ID dataset, called WMVEID863, with additional challenges such as motion
blur, significant background changes, and particularly intense flare
degradation. Comprehensive experiments on both the newly collected dataset and
public benchmark multi-spectral vehicle re-ID datasets demonstrate the superior
performance of the proposed FACENet compared to state-of-the-art methods,
especially in handling strong flares. The code and dataset will be released
soon
Calcium–magnesium–alumina–silicate (CMAS) resistance of LaPO4 thermal barrier coatings
Nanostructured LaPO4 thermal barrier coatings (TBCs) were prepared by air plasma spraying, and their resistance to calcium–magnesium–alumina–silicate (CMAS) attack at 1250 °C, 1300 °C and 1350 °C was investigated. The reaction products were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy and transmission electron microscopy. Exposed to CMAS attack for 0.5 h, a continuous dense reaction layer formed, which was mainly composed of P–Si apatite based on Ca2+xLa8-x(PO4)x(SiO4)6-xO2, anorthite and spinel phases. Beneath the reaction layer, little evidence of CMAS trace could be found. With the increase in temperature and heat treatment duration, the reaction layer became thick, while penetration depth of the molten CMAS changed slightly. Due to the formation of a reaction layer suppressing CMAS further infiltration, LaPO4 TBCs are highly resistant to CMAS attack
Addressing preferred orientation in single-particle cryo-EM through AI-generated auxiliary particles
The single-particle cryo-EM field faces the persistent challenge of preferred
orientation, lacking general computational solutions. We introduce cryoPROS, an
AI-based approach designed to address the above issue. By generating the
auxiliary particles with a conditional deep generative model, cryoPROS
addresses the intrinsic bias in orientation estimation for the observed
particles. We effectively employed cryoPROS in the cryo-EM single particle
analysis of the hemagglutinin trimer, showing the ability to restore the
near-atomic resolution structure on non-tilt data. Moreover, the enhanced
version named cryoPROS-MP significantly improves the resolution of the membrane
protein NaX using the no-tilted data that contains the effects of micelles.
Compared to the classical approaches, cryoPROS does not need special
experimental or image acquisition techniques, providing a purely computational
yet effective solution for the preferred orientation problem. Finally, we
conduct extensive experiments that establish the low risk of model bias and the
high robustness of cryoPROS
Study on TCM Syndrome Identification Modes of Coronary Heart Disease Based on Data Mining
Coronary heart disease (CHD) is one of the most important types of heart disease because of its high incidence and high mortality. TCM has played an important role in the treatment of CHD. Syndrome differentiation based on information from traditional four diagnostic methods has met challenges and questions with the rapid development and wide application of system biology. In this paper, methods of complex network and CHAID decision tree were applied to identify the TCM core syndromes of patients with CHD, and to establish TCM syndrome identification modes of CHD based on biological parameters. At the same time, external validation modes were also constructed to confirm the identification modes
Cognitive decline among older adults with heart diseases before and during the COVID-19 pandemic: A longitudinal cohort study
BackgroundLittle is known about the impact induced by the COVID-19 pandemic on the cognitive function of older adults with heart diseases. This study aimed to examine whether older adults with heart diseases suffered larger cognitive deterioration during the COVID-19 pandemic.MethodsThis study leveraged longitudinal data from the Health and Retirement Study (HRS), a nationally representative U.S. aging cohort with objective cognitive assessments measured before and during the pandemic. The interval from HRS waves 13 to 14 (April 2016 to June 2019) was defined as the pre-pandemic period to control the pre-existed cognitive difference between participants with and without heart diseases, and the interval from waves 14 to 15 (June 2019 to June 2021) was defined as the pandemic period. The HRS wave 14 survey was considered the baseline. The heart disease status was defined by a self-reported diagnosis. Linear mixed models were performed to evaluate and compare the cognitive differences during different periods.ResultsA total of 9,304 participants (women: 5,655, 60.8%; mean age: 65.8 ± 10.8 years) were included, and 2,119 (22.8%) had heart diseases. During the pre-pandemic period, there was no significant difference (−0.03, 95% CI: −0.22 to 0.15, P = 0.716) in the changes in global cognitive scores between participants with and without heart disease. During the pandemic period, a larger decreased change in the global cognitive score was observed in the heart disease group compared with the non-heart disease group (−0.37, 95% CI: −0.55 to −0.19, P < 0.001). An enlarged difference in global cognitive score was observed during the pandemic period (−0.33, 95% CI: −0.65 to −0.02, P = 0.036).ConclusionThe findings demonstrated that the population with heart diseases suffered more cognitive decline related to the pandemic, underscoring the necessity to provide immediate cognitive monitoring and interventions for the population with heart diseases
Robotic Cane as a Soft SuperLimb for Elderly Sit-to-Stand Assistance
Many researchers have identified robotics as a potential solution to the
aging population faced by many developed and developing countries. If so, how
should we address the cognitive acceptance and ambient control of elderly
assistive robots through design? In this paper, we proposed an explorative
design of an ambient SuperLimb (Supernumerary Robotic Limb) system that
involves a pneumatically-driven robotic cane for at-home motion assistance, an
inflatable vest for compliant human-robot interaction, and a depth sensor for
ambient intention detection. The proposed system aims at providing active
assistance during the sit-to-stand transition for at-home usage by the elderly
at the bedside, in the chair, and on the toilet. We proposed a modified
biomechanical model with a linear cane robot for closed-loop control
implementation. We validated the design feasibility of the proposed ambient
SuperLimb system including the biomechanical model, our result showed the
advantages in reducing lower limb efforts and elderly fall risks, yet the
detection accuracy using depth sensing and adjustments on the model still
require further research in the future. Nevertheless, we summarized empirical
guidelines to support the ambient design of elderly-assistive SuperLimb systems
for lower limb functional augmentation.Comment: 8 pages, 9 figures, accepted for IEEE RoboSoft 202
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