5,216 research outputs found
A Survey on IT-Techniques for a Dynamic Emergency Management in Large Infrastructures
This deliverable is a survey on the IT techniques that are relevant to the three use cases of the project EMILI. It describes the state-of-the-art in four complementary IT areas: Data cleansing, supervisory control and data acquisition, wireless sensor networks and complex event processing. Even though the deliverableās authors have tried to avoid a too technical language and have tried to explain every concept referred to, the deliverable might seem rather technical to readers so far little familiar with the techniques it describes
Practical issues for the implementation of survivability and recovery techniques in optical networks
The cognitive neuroscience of visual working memory
Visual working memory allows us to temporarily maintain and manipulate visual information in order to solve a task. The study of the brain mechanisms underlying this function began more than half a century ago, with Scoville and Milnerās (1957) seminal discoveries with amnesic patients. This timely collection of papers brings together diverse perspectives on the cognitive neuroscience of visual working memory from multiple fields that have traditionally been fairly disjointed: human neuroimaging, electrophysiological, behavioural and animal lesion studies, investigating both the developing and the adult brain
Multi-task Self-Supervised Learning for Human Activity Detection
Deep learning methods are successfully used in applications pertaining to
ubiquitous computing, health, and well-being. Specifically, the area of human
activity recognition (HAR) is primarily transformed by the convolutional and
recurrent neural networks, thanks to their ability to learn semantic
representations from raw input. However, to extract generalizable features,
massive amounts of well-curated data are required, which is a notoriously
challenging task; hindered by privacy issues, and annotation costs. Therefore,
unsupervised representation learning is of prime importance to leverage the
vast amount of unlabeled data produced by smart devices. In this work, we
propose a novel self-supervised technique for feature learning from sensory
data that does not require access to any form of semantic labels. We learn a
multi-task temporal convolutional network to recognize transformations applied
on an input signal. By exploiting these transformations, we demonstrate that
simple auxiliary tasks of the binary classification result in a strong
supervisory signal for extracting useful features for the downstream task. We
extensively evaluate the proposed approach on several publicly available
datasets for smartphone-based HAR in unsupervised, semi-supervised, and
transfer learning settings. Our method achieves performance levels superior to
or comparable with fully-supervised networks, and it performs significantly
better than autoencoders. Notably, for the semi-supervised case, the
self-supervised features substantially boost the detection rate by attaining a
kappa score between 0.7-0.8 with only 10 labeled examples per class. We get
similar impressive performance even if the features are transferred from a
different data source. While this paper focuses on HAR as the application
domain, the proposed technique is general and could be applied to a wide
variety of problems in other areas
RoSAS: Deep Semi-Supervised Anomaly Detection with Contamination-Resilient Continuous Supervision
Semi-supervised anomaly detection methods leverage a few anomaly examples to
yield drastically improved performance compared to unsupervised models.
However, they still suffer from two limitations: 1) unlabeled anomalies (i.e.,
anomaly contamination) may mislead the learning process when all the unlabeled
data are employed as inliers for model training; 2) only discrete supervision
information (such as binary or ordinal data labels) is exploited, which leads
to suboptimal learning of anomaly scores that essentially take on a continuous
distribution. Therefore, this paper proposes a novel semi-supervised anomaly
detection method, which devises \textit{contamination-resilient continuous
supervisory signals}. Specifically, we propose a mass interpolation method to
diffuse the abnormality of labeled anomalies, thereby creating new data samples
labeled with continuous abnormal degrees. Meanwhile, the contaminated area can
be covered by new data samples generated via combinations of data with correct
labels. A feature learning-based objective is added to serve as an optimization
constraint to regularize the network and further enhance the robustness w.r.t.
anomaly contamination. Extensive experiments on 11 real-world datasets show
that our approach significantly outperforms state-of-the-art competitors by
20%-30% in AUC-PR and obtains more robust and superior performance in settings
with different anomaly contamination levels and varying numbers of labeled
anomalies. The source code is available at https://github.com/xuhongzuo/rosas/.Comment: Accepted by Information Processing and Management (IP&M
- ā¦