47 research outputs found
ComPtr: Towards Diverse Bi-source Dense Prediction Tasks via A Simple yet General Complementary Transformer
Deep learning (DL) has advanced the field of dense prediction, while
gradually dissolving the inherent barriers between different tasks. However,
most existing works focus on designing architectures and constructing visual
cues only for the specific task, which ignores the potential uniformity
introduced by the DL paradigm. In this paper, we attempt to construct a novel
\underline{ComP}lementary \underline{tr}ansformer, \textbf{ComPtr}, for diverse
bi-source dense prediction tasks. Specifically, unlike existing methods that
over-specialize in a single task or a subset of tasks, ComPtr starts from the
more general concept of bi-source dense prediction. Based on the basic
dependence on information complementarity, we propose consistency enhancement
and difference awareness components with which ComPtr can evacuate and collect
important visual semantic cues from different image sources for diverse tasks,
respectively. ComPtr treats different inputs equally and builds an efficient
dense interaction model in the form of sequence-to-sequence on top of the
transformer. This task-generic design provides a smooth foundation for
constructing the unified model that can simultaneously deal with various
bi-source information. In extensive experiments across several representative
vision tasks, i.e. remote sensing change detection, RGB-T crowd counting,
RGB-D/T salient object detection, and RGB-D semantic segmentation, the proposed
method consistently obtains favorable performance. The code will be available
at \url{https://github.com/lartpang/ComPtr}
Multi-scale Interactive Network for Salient Object Detection
Deep-learning based salient object detection methods achieve great progress.
However, the variable scale and unknown category of salient objects are great
challenges all the time. These are closely related to the utilization of
multi-level and multi-scale features. In this paper, we propose the aggregate
interaction modules to integrate the features from adjacent levels, in which
less noise is introduced because of only using small up-/down-sampling rates.
To obtain more efficient multi-scale features from the integrated features, the
self-interaction modules are embedded in each decoder unit. Besides, the class
imbalance issue caused by the scale variation weakens the effect of the binary
cross entropy loss and results in the spatial inconsistency of the predictions.
Therefore, we exploit the consistency-enhanced loss to highlight the
fore-/back-ground difference and preserve the intra-class consistency.
Experimental results on five benchmark datasets demonstrate that the proposed
method without any post-processing performs favorably against 23
state-of-the-art approaches. The source code will be publicly available at
https://github.com/lartpang/MINet.Comment: Accepted by CVPR 202
CAVER: Cross-Modal View-Mixed Transformer for Bi-Modal Salient Object Detection
Most of the existing bi-modal (RGB-D and RGB-T) salient object detection
methods utilize the convolution operation and construct complex interweave
fusion structures to achieve cross-modal information integration. The inherent
local connectivity of the convolution operation constrains the performance of
the convolution-based methods to a ceiling. In this work, we rethink these
tasks from the perspective of global information alignment and transformation.
Specifically, the proposed \underline{c}ross-mod\underline{a}l
\underline{v}iew-mixed transform\underline{er} (CAVER) cascades several
cross-modal integration units to construct a top-down transformer-based
information propagation path. CAVER treats the multi-scale and multi-modal
feature integration as a sequence-to-sequence context propagation and update
process built on a novel view-mixed attention mechanism. Besides, considering
the quadratic complexity w.r.t. the number of input tokens, we design a
parameter-free patch-wise token re-embedding strategy to simplify operations.
Extensive experimental results on RGB-D and RGB-T SOD datasets demonstrate that
such a simple two-stream encoder-decoder framework can surpass recent
state-of-the-art methods when it is equipped with the proposed components.Comment: Updated version, more flexible structure, better performanc
ZoomNeXt: A Unified Collaborative Pyramid Network for Camouflaged Object Detection
Recent camouflaged object detection (COD) attempts to segment objects
visually blended into their surroundings, which is extremely complex and
difficult in real-world scenarios. Apart from the high intrinsic similarity
between camouflaged objects and their background, objects are usually diverse
in scale, fuzzy in appearance, and even severely occluded. To this end, we
propose an effective unified collaborative pyramid network which mimics human
behavior when observing vague images and videos, \textit{i.e.}, zooming in and
out. Specifically, our approach employs the zooming strategy to learn
discriminative mixed-scale semantics by the multi-head scale integration and
rich granularity perception units, which are designed to fully explore
imperceptible clues between candidate objects and background surroundings. The
former's intrinsic multi-head aggregation provides more diverse visual
patterns. The latter's routing mechanism can effectively propagate inter-frame
difference in spatiotemporal scenarios and adaptively ignore static
representations. They provides a solid foundation for realizing a unified
architecture for static and dynamic COD. Moreover, considering the uncertainty
and ambiguity derived from indistinguishable textures, we construct a simple
yet effective regularization, uncertainty awareness loss, to encourage
predictions with higher confidence in candidate regions. Our highly
task-friendly framework consistently outperforms existing state-of-the-art
methods in image and video COD benchmarks. The code will be available at
\url{https://github.com/lartpang/ZoomNeXt}.Comment: Extensions to the conference version: arXiv:2203.02688; Fixed some
word error
Freeze-thaw damage assessment of engineered cementitious composites using the electrochemical impedance spectroscopy method
The mechanical properties of engineered cementitious composites (ECC) in service in cold regions can be significantly degraded by periodic freezing and thawing. In this work, the damage degree of freeze–thaw of ECC was systematically assessed by using the electrochemical impedance spectroscopy (EIS) technique. In addition, Nuclear Magnetic Resonance (NMR) Relaxometry measurements were also performed to obtain pore structure parameters, and the uniaxial tensile tests were also carried out to analyse the tensile performance after freeze–thaw cycles. From the acquired results, it was demonstrated that the EIS behaviour of ECC varied with the freeze–thaw cycles. The diameter of the Nyquist curve in high-frequency was gradually reduced by increasing the freeze–thaw cycles. Furthermore, the volume resistance of ECC after freeze–thaw gradually decreased with the increase in the number of freeze–thaw cycles. The simplified microstructure and conductive paths were used to describe the freeze–thaw damage mechanism of ECC. An equivalent circuit model of ECC exposed to freeze–thaw cycles was proposed, and the parameters of the equivalent circuit model were thoroughly analysed. The experimental findings clearly indicate that the EIS method is an appropriate technique for evaluating the damage degree of freeze–thaw of ECC
Emerging role of the calcium-activated, small conductance, SK3 K <sup>+</sup> channel in distal tubule function: Regulation by TRPV4
The Ca2+-activated, maxi-K (BK) K+ channel, with low Ca2+-binding affinity, is expressed in the distal tubule of the nephron and contributes to flow-dependent K+ secretion. In the present study we demonstrate that the Ca2+-activated, SK3 (KCa2.3) K + channel, with high Ca2+-binding affinity, is also expressed in the mouse kidney (RT-PCR, immunoblots). Immunohistochemical evaluations using tubule specific markers demonstrate significant expression of SK3 in the distal tubule and the entire collecting duct system, including the connecting tubule (CNT) and cortical collecting duct (CCD). In CNT and CCD, main sites for K+ secretion, the highest levels of expression were along the apical (luminal) cell membranes, including for both principal cells (PCs) and intercalated cells (ICs), posturing the channel for Ca2+- dependent K+ secretion. Fluorescent assessment of cell membrane potential in native, split-opened CCD, demonstrated that selective activation of the Ca2+-permeable TRPV4 channel, thereby inducing Ca2+ influx and elevating intracellular Ca2+ levels, activated both the SK3 channel and the BK channel leading to hyperpolarization of the cell membrane. The hyperpolarization response was decreased to a similar extent by either inhibition of SK3 channel with the selective SK antagonist, apamin, or by inhibition of the BK channel with the selective antagonist, iberiotoxin (IbTX). Addition of both inhibitors produced a further depolarization, indicating cooperative effects of the two channels on Vm. It is concluded that SK3 is functionally expressed in the distal nephron and collecting ducts where induction of TRPV4-mediated Ca2+ influx, leading to elevated intracellular Ca2+ levels, activates this high Ca2+- affinity K+ channel. Further, with sites of expression localized to the apical cell membrane, especially in the CNT and CCD, SK3 is poised to be a key pathway for Ca2+-dependent regulation of membrane potential and K+ secretion. © 2014 Berrout et al