641 research outputs found
An adsorbed gas estimation model for shale gas reservoirs via statistical learning
Shale gas plays an important role in reducing pollution and adjusting the
structure of world energy. Gas content estimation is particularly significant
in shale gas resource evaluation. There exist various estimation methods, such
as first principle methods and empirical models. However, resource evaluation
presents many challenges, especially the insufficient accuracy of existing
models and the high cost resulting from time-consuming adsorption experiments.
In this research, a low-cost and high-accuracy model based on geological
parameters is constructed through statistical learning methods to estimate
adsorbed shale gas conten
A Survey on Open-Vocabulary Detection and Segmentation: Past, Present, and Future
As the most fundamental tasks of computer vision, object detection and
segmentation have made tremendous progress in the deep learning era. Due to the
expensive manual labeling, the annotated categories in existing datasets are
often small-scale and pre-defined, i.e., state-of-the-art detectors and
segmentors fail to generalize beyond the closed-vocabulary. To resolve this
limitation, the last few years have witnessed increasing attention toward
Open-Vocabulary Detection (OVD) and Segmentation (OVS). In this survey, we
provide a comprehensive review on the past and recent development of OVD and
OVS. To this end, we develop a taxonomy according to the type of task and
methodology. We find that the permission and usage of weak supervision signals
can well discriminate different methodologies, including: visual-semantic space
mapping, novel visual feature synthesis, region-aware training,
pseudo-labeling, knowledge distillation-based, and transfer learning-based. The
proposed taxonomy is universal across different tasks, covering object
detection, semantic/instance/panoptic segmentation, 3D scene and video
understanding. In each category, its main principles, key challenges,
development routes, strengths, and weaknesses are thoroughly discussed. In
addition, we benchmark each task along with the vital components of each
method. Finally, several promising directions are provided to stimulate future
research
Deep-LK for Efficient Adaptive Object Tracking
In this paper we present a new approach for efficient regression based object
tracking which we refer to as Deep- LK. Our approach is closely related to the
Generic Object Tracking Using Regression Networks (GOTURN) framework of Held et
al. We make the following contributions. First, we demonstrate that there is a
theoretical relationship between siamese regression networks like GOTURN and
the classical Inverse-Compositional Lucas & Kanade (IC-LK) algorithm. Further,
we demonstrate that unlike GOTURN IC-LK adapts its regressor to the appearance
of the currently tracked frame. We argue that this missing property in GOTURN
can be attributed to its poor performance on unseen objects and/or viewpoints.
Second, we propose a novel framework for object tracking - which we refer to as
Deep-LK - that is inspired by the IC-LK framework. Finally, we show impressive
results demonstrating that Deep-LK substantially outperforms GOTURN.
Additionally, we demonstrate comparable tracking performance to current state
of the art deep-trackers whilst being an order of magnitude (i.e. 100 FPS)
computationally efficient
Place recognition: An Overview of Vision Perspective
Place recognition is one of the most fundamental topics in computer vision
and robotics communities, where the task is to accurately and efficiently
recognize the location of a given query image. Despite years of wisdom
accumulated in this field, place recognition still remains an open problem due
to the various ways in which the appearance of real-world places may differ.
This paper presents an overview of the place recognition literature. Since
condition invariant and viewpoint invariant features are essential factors to
long-term robust visual place recognition system, We start with traditional
image description methodology developed in the past, which exploit techniques
from image retrieval field. Recently, the rapid advances of related fields such
as object detection and image classification have inspired a new technique to
improve visual place recognition system, i.e., convolutional neural networks
(CNNs). Thus we then introduce recent progress of visual place recognition
system based on CNNs to automatically learn better image representations for
places. Eventually, we close with discussions and future work of place
recognition.Comment: Applied Sciences (2018
Channel prior convolutional attention for medical image segmentation
Characteristics such as low contrast and significant organ shape variations
are often exhibited in medical images. The improvement of segmentation
performance in medical imaging is limited by the generally insufficient
adaptive capabilities of existing attention mechanisms. An efficient Channel
Prior Convolutional Attention (CPCA) method is proposed in this paper,
supporting the dynamic distribution of attention weights in both channel and
spatial dimensions. Spatial relationships are effectively extracted while
preserving the channel prior by employing a multi-scale depth-wise
convolutional module. The ability to focus on informative channels and
important regions is possessed by CPCA. A segmentation network called CPCANet
for medical image segmentation is proposed based on CPCA. CPCANet is validated
on two publicly available datasets. Improved segmentation performance is
achieved by CPCANet while requiring fewer computational resources through
comparisons with state-of-the-art algorithms. Our code is publicly available at
\url{https://github.com/Cuthbert-Huang/CPCANet}
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