498 research outputs found
Application of Acoustic Emission Technique in the Monitoring of Masonry Structures
The application of acoustic emission (AE) technique in monitoring the safe condition is a useful technique in steel and concrete structures, whereas its application is restrained in masonry structures due to the layered property. Qualitative and quantitative analyses were investigated in this research to improve the AE application in masonry structures. For quantitative analysis, an improved localization method is proposed to give more reliable crack localization results. In the proposed method, the parameter ξ on the behavior of inhomogeneity of the monitored structure could minimize the unavoidable propagation delay caused by the layers in the masonry structure. The rest results approved the reliability of the proposed method in masonry structures. For qualitative analysis, the parameter analysis, including the cumulative AE event, frequency distribution, time-scaling exponent, and b-value, was adopted to monitor one historical church and was approved to be useful
Fire Performance of Steel Reinforced Concrete (SRC) Structures
AbstractThis paper summarizes some of the recent research published on steel reinforced concrete (SRC) structures under or after exposure to fire. The contents include: 1) Fire resistance and post-fire behavior of SRC columns; 2) Fire performance of SRC column to beam joints, by adopting a loading sequence including initial loading, heating, cooling and post-fire loading; 3) Fire resistance and post-fire behavior of SRC composite frames
Noisy Correspondence Learning with Meta Similarity Correction
Despite the success of multimodal learning in cross-modal retrieval task, the
remarkable progress relies on the correct correspondence among multimedia data.
However, collecting such ideal data is expensive and time-consuming. In
practice, most widely used datasets are harvested from the Internet and
inevitably contain mismatched pairs. Training on such noisy correspondence
datasets causes performance degradation because the cross-modal retrieval
methods can wrongly enforce the mismatched data to be similar. To tackle this
problem, we propose a Meta Similarity Correction Network (MSCN) to provide
reliable similarity scores. We view a binary classification task as the
meta-process that encourages the MSCN to learn discrimination from positive and
negative meta-data. To further alleviate the influence of noise, we design an
effective data purification strategy using meta-data as prior knowledge to
remove the noisy samples. Extensive experiments are conducted to demonstrate
the strengths of our method in both synthetic and real-world noises, including
Flickr30K, MS-COCO, and Conceptual Captions.Comment: Accepted at CVPR 202
Analysis of concrete-filled stainless steel tubular columns under combined fire and loading
[EN] In fire scenarios, concrete-filled stainless steel tubular (CFSST) columns undergo initial loading at ambient temperature, loading during the heating phase as the fire develops, loading during the cooling phase as the fire dies out and continual loading after the fire. CFSST columns may fail some points during this process under combined fire and loading. In this paper, the failure modes and corresponding working mechanism of CFSST columns subjected to an entire loading and fire history are investigated. Sequentially coupled thermal-stress analyses in ABAQUS are employed to establish the temperature field and structural response of the CFSST column. To improve the precision of the finite element (FE) model, the influence of moisture on the thermal conductivity and specific heat of concrete during both the heating and cooling phases is considered using subroutines. Existing fire and post-fire test data of CFSST columns are used to validate the FE models. Comparisons between predicted and test results confirm that the accuracy of the FE models is acceptable; the FE models are then extended to simulate a typical CFSST column subjected to the entire loading and fire history. The behaviour of the CFSST column is explained by analysis of the temperature distribution, load versus axial deformation curves and failure response.The research reported in the paper is part of the Project 51308539 supported by the National
Natural Science Foundation of China. The financial support is highly appreciated.Tan, Q.; Gardner, L.; Han, L.; Song, D. (2018). Analysis of concrete-filled stainless steel tubular columns under combined fire and loading. En Proceedings of the 12th International Conference on Advances in Steel-Concrete Composite Structures. ASCCS 2018. Editorial Universitat Politècnica de València. 825-833. https://doi.org/10.4995/ASCCS2018.2018.7206OCS82583
Exploring and Exploiting Uncertainty for Incomplete Multi-View Classification
Classifying incomplete multi-view data is inevitable since arbitrary view
missing widely exists in real-world applications. Although great progress has
been achieved, existing incomplete multi-view methods are still difficult to
obtain a trustworthy prediction due to the relatively high uncertainty nature
of missing views. First, the missing view is of high uncertainty, and thus it
is not reasonable to provide a single deterministic imputation. Second, the
quality of the imputed data itself is of high uncertainty. To explore and
exploit the uncertainty, we propose an Uncertainty-induced Incomplete
Multi-View Data Classification (UIMC) model to classify the incomplete
multi-view data under a stable and reliable framework. We construct a
distribution and sample multiple times to characterize the uncertainty of
missing views, and adaptively utilize them according to the sampling quality.
Accordingly, the proposed method realizes more perceivable imputation and
controllable fusion. Specifically, we model each missing data with a
distribution conditioning on the available views and thus introducing
uncertainty. Then an evidence-based fusion strategy is employed to guarantee
the trustworthy integration of the imputed views. Extensive experiments are
conducted on multiple benchmark data sets and our method establishes a
state-of-the-art performance in terms of both performance and trustworthiness.Comment: CVP
Semantic Equivariant Mixup
Mixup is a well-established data augmentation technique, which can extend the
training distribution and regularize the neural networks by creating ''mixed''
samples based on the label-equivariance assumption, i.e., a proportional mixup
of the input data results in the corresponding labels being mixed in the same
proportion. However, previous mixup variants may fail to exploit the
label-independent information in mixed samples during training, which usually
contains richer semantic information. To further release the power of mixup, we
first improve the previous label-equivariance assumption by the
semantic-equivariance assumption, which states that the proportional mixup of
the input data should lead to the corresponding representation being mixed in
the same proportion. Then a generic mixup regularization at the representation
level is proposed, which can further regularize the model with the semantic
information in mixed samples. At a high level, the proposed semantic
equivariant mixup (sem) encourages the structure of the input data to be
preserved in the representation space, i.e., the change of input will result in
the obtained representation information changing in the same way. Different
from previous mixup variants, which tend to over-focus on the label-related
information, the proposed method aims to preserve richer semantic information
in the input with semantic-equivariance assumption, thereby improving the
robustness of the model against distribution shifts. We conduct extensive
empirical studies and qualitative analyzes to demonstrate the effectiveness of
our proposed method. The code of the manuscript is in the supplement.Comment: Under revie
Towards Large-Scale Small Object Detection: Survey and Benchmarks
With the rise of deep convolutional neural networks, object detection has
achieved prominent advances in past years. However, such prosperity could not
camouflage the unsatisfactory situation of Small Object Detection (SOD), one of
the notoriously challenging tasks in computer vision, owing to the poor visual
appearance and noisy representation caused by the intrinsic structure of small
targets. In addition, large-scale dataset for benchmarking small object
detection methods remains a bottleneck. In this paper, we first conduct a
thorough review of small object detection. Then, to catalyze the development of
SOD, we construct two large-scale Small Object Detection dAtasets (SODA),
SODA-D and SODA-A, which focus on the Driving and Aerial scenarios
respectively. SODA-D includes 24828 high-quality traffic images and 278433
instances of nine categories. For SODA-A, we harvest 2513 high resolution
aerial images and annotate 872069 instances over nine classes. The proposed
datasets, as we know, are the first-ever attempt to large-scale benchmarks with
a vast collection of exhaustively annotated instances tailored for
multi-category SOD. Finally, we evaluate the performance of mainstream methods
on SODA. We expect the released benchmarks could facilitate the development of
SOD and spawn more breakthroughs in this field. Datasets and codes are
available at: \url{https://shaunyuan22.github.io/SODA}
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