139 research outputs found
Recent advances in deep learning for object detection
Object detection is a fundamental visual recognition problem in computer
vision and has been widely studied in the past decades. Visual object detection
aims to find objects of certain target classes with precise localization in a
given image and assign each object instance a corresponding class label. Due to
the tremendous successes of deep learning based image classification, object
detection techniques using deep learning have been actively studied in recent
years. In this paper, we give a comprehensive survey of recent advances in
visual object detection with deep learning. By reviewing a large body of recent
related work in literature, we systematically analyze the existing object
detection frameworks and organize the survey into three major parts: (i)
detection components, (ii) learning strategies, and (iii) applications &
benchmarks. In the survey, we cover a variety of factors affecting the
detection performance in detail, such as detector architectures, feature
learning, proposal generation, sampling strategies, etc. Finally, we discuss
several future directions to facilitate and spur future research for visual
object detection with deep learning. Keywords: Object Detection, Deep Learning,
Deep Convolutional Neural Network
A Map-matching Algorithm with Extraction of Multi-group Information for Low-frequency Data
The growing use of probe vehicles generates a huge number of GNSS data.
Limited by the satellite positioning technology, further improving the accuracy
of map-matching is challenging work, especially for low-frequency trajectories.
When matching a trajectory, the ego vehicle's spatial-temporal information of
the present trip is the most useful with the least amount of data. In addition,
there are a large amount of other data, e.g., other vehicles' state and past
prediction results, but it is hard to extract useful information for matching
maps and inferring paths. Most map-matching studies only used the ego vehicle's
data and ignored other vehicles' data. Based on it, this paper designs a new
map-matching method to make full use of "Big data". We first sort all data into
four groups according to their spatial and temporal distance from the present
matching probe which allows us to sort for their usefulness. Then we design
three different methods to extract valuable information (scores) from them: a
score for speed and bearing, a score for historical usage, and a score for
traffic state using the spectral graph Markov neutral network. Finally, we use
a modified top-K shortest-path method to search the candidate paths within an
ellipse region and then use the fused score to infer the path (projected
location). We test the proposed method against baseline algorithms using a
real-world dataset in China. The results show that all scoring methods can
enhance map-matching accuracy. Furthermore, our method outperforms the others,
especially when GNSS probing frequency is less than 0.01 Hz.Comment: 10 pages, 11 figures, 4 table
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