scholarly journals Vehicle Trajectory Estimation Based on Fusion of Visual Motion Features and Deep Learning

Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7969
Author(s):  
Lianen Qu ◽  
Matthew N. Dailey

Driver situation awareness is critical for safety. In this paper, we propose a fast, accurate method for obtaining real-time situation awareness using a single type of sensor: monocular cameras. The system tracks the host vehicle’s trajectory using sparse optical flow and tracks vehicles in the surrounding environment using convolutional neural networks. Optical flow is used to measure the linear and angular velocity of the host vehicle. The convolutional neural networks are used to measure target vehicles’ positions relative to the host vehicle using image-based detections. Finally, the system fuses host and target vehicle trajectories in the world coordinate system using the velocity of the host vehicle and the target vehicles’ relative positions with the aid of an Extended Kalman Filter (EKF). We implement and test our model quantitatively in simulation and qualitatively on real-world test video. The results show that the algorithm is superior to state-of-the-art sequential state estimation methods such as visual SLAM in performing accurate global localization and trajectory estimation for host and target vehicles.

Author(s):  
André Souza Brito ◽  
Marcelo Bernardes Vieira ◽  
Saulo Moraes Villela ◽  
Hemerson Tacon ◽  
Hugo Lima Chaves ◽  
...  

Author(s):  
Simon Veldkamp ◽  
Kirien Whan ◽  
Sjoerd Dirksen ◽  
Maurice Schmeits

AbstractCurrent statistical post-processing methods for probabilistic weather forecasting are not capable of using full spatial patterns from the numerical weather prediction (NWP) model. In this paper we incorporate spatial wind speed information by using convolutional neural networks (CNNs) and obtain probabilistic wind speed forecasts in the Netherlands for 48 hours ahead, based on KNMI’s deterministic Harmonie-Arome NWP model. The probabilistic forecasts from the CNNs are shown to have higher Brier skill scores for medium to higher wind speeds, as well as a better continuous ranked probability score (CRPS) and logarithmic score, than the forecasts from fully connected neural networks and quantile regression forests. As a secondary result, we have compared the CNNs using 3 different density estimation methods (quantized softmax (QS), kernel mixture networks, and fitting a truncated normal distribution), and found the probabilistic forecasts based on the QS method to be best.


2020 ◽  
Author(s):  
Carlos Caetano ◽  
Jefersson Alex Dos Santos ◽  
William Robson Schwartz

This work addresses the activity recognition problem. We propose two different representations based on motion information for activity recognition. The first representation is a novel temporal stream for two-stream Convolutional Neural Networks (CNNs) that receives as input images computed from the optical flow magnitude and orientation to learn the motion in a better and richer manner. The method applies simple non-linear transformations on the vertical and horizontal components of the optical flow to generate input images for the temporal stream. The second representation is a novel skeleton image representation to be used as input of CNNs. The approach encodes the temporal dynamics by explicitly computing the magnitude and orientation values of the skeleton joints. Experiments carried out on challenging well-known activity recognition datasets (UCF101, NTU RGB+D 60 and NTU RGB+D 120) demonstrate that the proposed representations achieve results in the state of the art, indicating the suitability of our approaches as video representations.


2021 ◽  
Author(s):  
Haobo Chen ◽  
Yuqun Wang ◽  
Jie Shi ◽  
Jingyu Xiong ◽  
Jianwei Jiang ◽  
...  

Abstract Objective Automated segmentation of lymph nodes (LNs) in ultrasound images is a challenging task mainly due to the presence of speckle noise and echogenic hila. In this paper, we propose a fully automatic and accurate method for LN segmentation in ultrasound. Methods The proposed segmentation method integrates diffusion-based despeckling, U-Net convolutional neural networks and morphological operations. Firstly, we suppress speckle noise and enhance lymph node edges using the Gabor-based anisotropic diffusion (GAD). Secondly, a modified U-Net model is proposed to segment LNs excluding echogenic hila. Finally, morphological operations are adopted to segment entire LNs by filling the regions of echogenic hila.Results A total of 531 lymph nodes from 526 patients were included to evaluate the proposed method. Quantitative metrics of segmentation performance, including the accuracy, sensitivity, specificity, Jaccard similarity and Dice coefficient, reached 0.934, 0.939, 0.937, 0.763 and 0.865, respectively.Conclusion The proposed method automatically and accurately segments LNs in ultrasound, which may assist artificially intelligent diagnosis of lymph node diseases.


2019 ◽  
Vol 368 ◽  
pp. 124-132 ◽  
Author(s):  
Mingliang Zhai ◽  
Xuezhi Xiang ◽  
Rongfang Zhang ◽  
Ning Lv ◽  
Abdulmotaleb El Saddik

2019 ◽  
Vol 78 (18) ◽  
pp. 25873-25888 ◽  
Author(s):  
Ahmed R. Hawas ◽  
Heba A. El-Khobby ◽  
M. Abd-Elnaby ◽  
Fathi E. Abd El-Samie

2018 ◽  
Vol 77 (22) ◽  
pp. 29231-29244 ◽  
Author(s):  
Meijun Sun ◽  
Ziqi Zhou ◽  
Dong Zhang ◽  
Zheng Wang

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