4 research outputs found
Depth Completion with Multiple Balanced Bases and Confidence for Dense Monocular SLAM
Dense SLAM based on monocular cameras does indeed have immense application
value in the field of AR/VR, especially when it is performed on a mobile
device. In this paper, we propose a novel method that integrates a light-weight
depth completion network into a sparse SLAM system using a multi-basis depth
representation, so that dense mapping can be performed online even on a mobile
phone. Specifically, we present a specifically optimized multi-basis depth
completion network, called BBC-Net, tailored to the characteristics of
traditional sparse SLAM systems. BBC-Net can predict multiple balanced bases
and a confidence map from a monocular image with sparse points generated by
off-the-shelf keypoint-based SLAM systems. The final depth is a linear
combination of predicted depth bases that can be optimized by tuning the
corresponding weights. To seamlessly incorporate the weights into traditional
SLAM optimization and ensure efficiency and robustness, we design a set of
depth weight factors, which makes our network a versatile plug-in module,
facilitating easy integration into various existing sparse SLAM systems and
significantly enhancing global depth consistency through bundle adjustment. To
verify the portability of our method, we integrate BBC-Net into two
representative SLAM systems. The experimental results on various datasets show
that the proposed method achieves better performance in monocular dense mapping
than the state-of-the-art methods. We provide an online demo running on a
mobile phone, which verifies the efficiency and mapping quality of the proposed
method in real-world scenarios
A Novel Tunable Multi-Frequency Hybrid Vibration Energy Harvester Using Piezoelectric and Electromagnetic Conversion Mechanisms
This paper presents a novel tunable multi-frequency hybrid energy harvester (HEH). It consists of a piezoelectric energy harvester (PEH) and an electromagnetic energy harvester (EMEH), which are coupled with magnetic interaction. An electromechanical coupling model was developed and numerically simulated. The effects of magnetic force, mass ratio, stiffness ratio, and mechanical damping ratios on the output power were investigated. A prototype was fabricated and characterized by experiments. The measured first peak power increases by 16.7% and 833.3% compared with that of the multi-frequency EMEH and the multi-frequency PEH, respectively. It is 2.36 times more than the combined output power of the linear PEH and linear EMEH at 22.6 Hz. The half-power bandwidth for the first peak power is also broadened. Numerical results agree well with the experimental data. It is indicated that magnetic interaction can tune the resonant frequencies. Both magnetic coupling configuration and hybrid conversion mechanism contribute to enhancing the output power and widening the operation bandwidth. The magnitude and direction of magnetic force have significant effects on the performance of the HEH. This proposed HEH is an effective approach to improve the generating performance of the micro-scale energy harvesting devices in low-frequency range
Non-coding RNA mediates endoplasmic reticulum stress-induced apoptosis in heart disease
Apoptosis is a complex and highly self-regulating form of cell death, which is an important cause of the continuous decline in ventricular function and is widely involved in the occurrence and development of heart failure, myocardial infarction, and myocarditis. Endoplasmic reticulum stress plays a crucial role in apoptosis-inducing. Accumulation of misfolded or unfolded proteins causes cells to undergo a stress response called unfolded protein response (UPR). UPR initially has a cardioprotective effect. Nevertheless, prolonged and severe ER stress will lead up to apoptosis of stressed cells. Non-coding RNA is a type of RNA that does not code proteins. An ever-increasing number of studies have shown that non-coding RNAs are involved in regulating endoplasmic reticulum stress-induced cardiomyocyte injury and apoptosis. In this study, the effects of miRNA and LncRNA on endoplasmic reticulum stress in various heart diseases were mainly discussed to clarify their protective effects and potential therapeutic strategies for apoptosis
Solid-State Lithium Battery Cycle Life Prediction Using Machine Learning
Battery lifetime prediction is a promising direction for the development of next-generation smart energy storage systems. However, complicated degradation mechanisms, different assembly processes, and various operation conditions of the batteries bring tremendous challenges to battery life prediction. In this work, charge/discharge data of 12 solid-state lithium polymer batteries were collected with cycle lives ranging from 71 to 213 cycles. The remaining useful life of these batteries was predicted by using a machine learning algorithm, called symbolic regression. After populations of breed, mutation, and evolution training, the test accuracy of the quantitative prediction of cycle life reached 87.9%. This study shows the great prospect of a data-driven machine learning algorithm in the prediction of solid-state battery lifetimes, and it provides a new approach for the batch classification, echelon utilization, and recycling of batteries