7,982 research outputs found
UMSL Bulletin 2023-2024
The 2023-2024 Bulletin and Course Catalog for the University of Missouri St. Louis.https://irl.umsl.edu/bulletin/1088/thumbnail.jp
Representation Learning With Hidden Unit Clustering For Low Resource Speech Applications
The representation learning of speech, without textual resources, is an area
of significant interest for many low resource speech applications. In this
paper, we describe an approach to self-supervised representation learning from
raw audio using a hidden unit clustering (HUC) framework. The input to the
model consists of audio samples that are windowed and processed with 1-D
convolutional layers. The learned "time-frequency" representations from the
convolutional neural network (CNN) module are further processed with long short
term memory (LSTM) layers which generate a contextual vector representation for
every windowed segment. The HUC framework, allowing the categorization of the
representations into a small number of phoneme-like units, is used to train the
model for learning semantically rich speech representations. The targets
consist of phoneme-like pseudo labels for each audio segment and these are
generated with an iterative k-means algorithm. We explore techniques that
improve the speaker invariance of the learned representations and illustrate
the effectiveness of the proposed approach on two settings, i) completely
unsupervised speech applications on the sub-tasks described as part of the
ZeroSpeech 2021 challenge and ii) semi-supervised automatic speech recognition
(ASR) applications on the TIMIT dataset and on the GramVaani challenge Hindi
dataset. In these experiments, we achieve state-of-art results for various
ZeroSpeech tasks. Further, on the ASR experiments, the HUC representations are
shown to improve significantly over other established benchmarks based on
Wav2vec, HuBERT and Best-RQ
The State of the Art in Deep Learning Applications, Challenges, and Future Prospects::A Comprehensive Review of Flood Forecasting and Management
Floods are a devastating natural calamity that may seriously harm both infrastructure and people. Accurate flood forecasts and control are essential to lessen these effects and safeguard populations. By utilizing its capacity to handle massive amounts of data and provide accurate forecasts, deep learning has emerged as a potent tool for improving flood prediction and control. The current state of deep learning applications in flood forecasting and management is thoroughly reviewed in this work. The review discusses a variety of subjects, such as the data sources utilized, the deep learning models used, and the assessment measures adopted to judge their efficacy. It assesses current approaches critically and points out their advantages and disadvantages. The article also examines challenges with data accessibility, the interpretability of deep learning models, and ethical considerations in flood prediction. The report also describes potential directions for deep-learning research to enhance flood predictions and control. Incorporating uncertainty estimates into forecasts, integrating many data sources, developing hybrid models that mix deep learning with other methodologies, and enhancing the interpretability of deep learning models are a few of these. These research goals can help deep learning models become more precise and effective, which will result in better flood control plans and forecasts. Overall, this review is a useful resource for academics and professionals working on the topic of flood forecasting and management. By reviewing the current state of the art, emphasizing difficulties, and outlining potential areas for future study, it lays a solid basis. Communities may better prepare for and lessen the destructive effects of floods by implementing cutting-edge deep learning algorithms, thereby protecting people and infrastructure
Invariant Slot Attention: Object Discovery with Slot-Centric Reference Frames
Automatically discovering composable abstractions from raw perceptual data is
a long-standing challenge in machine learning. Recent slot-based neural
networks that learn about objects in a self-supervised manner have made
exciting progress in this direction. However, they typically fall short at
adequately capturing spatial symmetries present in the visual world, which
leads to sample inefficiency, such as when entangling object appearance and
pose. In this paper, we present a simple yet highly effective method for
incorporating spatial symmetries via slot-centric reference frames. We
incorporate equivariance to per-object pose transformations into the attention
and generation mechanism of Slot Attention by translating, scaling, and
rotating position encodings. These changes result in little computational
overhead, are easy to implement, and can result in large gains in terms of data
efficiency and overall improvements to object discovery. We evaluate our method
on a wide range of synthetic object discovery benchmarks namely CLEVR,
Tetrominoes, CLEVRTex, Objects Room and MultiShapeNet, and show promising
improvements on the challenging real-world Waymo Open dataset.Comment: Accepted at ICML 2023. Project page: https://invariantsa.github.io
Reinforcement learning in large state action spaces
Reinforcement learning (RL) is a promising framework for training intelligent agents which learn to optimize long term utility by directly interacting with the environment. Creating RL methods which scale to large state-action spaces is a critical problem towards ensuring real world deployment of RL systems. However, several challenges limit the applicability of RL to large scale settings. These include difficulties with exploration, low sample efficiency, computational intractability, task constraints like decentralization and lack of guarantees about important properties like performance, generalization and robustness in potentially unseen scenarios.
This thesis is motivated towards bridging the aforementioned gap. We propose several principled algorithms and frameworks for studying and addressing the above challenges RL. The proposed methods cover a wide range of RL settings (single and multi-agent systems (MAS) with all the variations in the latter, prediction and control, model-based and model-free methods, value-based and policy-based methods). In this work we propose the first results on several different problems: e.g. tensorization of the Bellman equation which allows exponential sample efficiency gains (Chapter 4), provable suboptimality arising from structural constraints in MAS(Chapter 3), combinatorial generalization results in cooperative MAS(Chapter 5), generalization results on observation shifts(Chapter 7), learning deterministic policies in a probabilistic RL framework(Chapter 6). Our algorithms exhibit provably enhanced performance and sample efficiency along with better scalability. Additionally, we also shed light on generalization aspects of the agents under different frameworks. These properties have been been driven by the use of several advanced tools (e.g. statistical machine learning, state abstraction, variational inference, tensor theory).
In summary, the contributions in this thesis significantly advance progress towards making RL agents ready for large scale, real world applications
The role of artificial intelligence-driven soft sensors in advanced sustainable process industries: a critical review
With the predicted depletion of natural resources and alarming environmental issues, sustainable development has become a popular as well as a much-needed concept in modern process industries. Hence, manufacturers are quite keen on adopting novel process monitoring techniques to enhance product quality and process efficiency while minimizing possible adverse environmental impacts. Hardware sensors are employed in process industries to aid process monitoring and control, but they are associated with many limitations such as disturbances to the process flow, measurement delays, frequent need for maintenance, and high capital costs. As a result, soft sensors have become an attractive alternative for predicting quality-related parameters that are ‘hard-to-measure’ using hardware sensors. Due to their promising features over hardware counterparts, they have been employed across different process industries. This article attempts to explore the state-of-the-art artificial intelligence (Al)-driven soft sensors designed for process industries and their role in achieving the goal of sustainable development. First, a general introduction is given to soft sensors, their applications in different process industries, and their significance in achieving sustainable development goals. AI-based soft sensing algorithms are then introduced. Next, a discussion on how AI-driven soft sensors contribute toward different sustainable manufacturing strategies of process industries is provided. This is followed by a critical review of the most recent state-of-the-art AI-based soft sensors reported in the literature. Here, the use of powerful AI-based algorithms for addressing the limitations of traditional algorithms, that restrict the soft sensor performance is discussed. Finally, the challenges and limitations associated with the current soft sensor design, application, and maintenance aspects are discussed with possible future directions for designing more intelligent and smart soft sensing technologies to cater the future industrial needs
Introduction to Facial Micro Expressions Analysis Using Color and Depth Images: A Matlab Coding Approach (Second Edition, 2023)
The book attempts to introduce a gentle introduction to the field of Facial
Micro Expressions Recognition (FMER) using Color and Depth images, with the aid
of MATLAB programming environment. FMER is a subset of image processing and it
is a multidisciplinary topic to analysis. So, it requires familiarity with
other topics of Artifactual Intelligence (AI) such as machine learning, digital
image processing, psychology and more. So, it is a great opportunity to write a
book which covers all of these topics for beginner to professional readers in
the field of AI and even without having background of AI. Our goal is to
provide a standalone introduction in the field of MFER analysis in the form of
theorical descriptions for readers with no background in image processing with
reproducible Matlab practical examples. Also, we describe any basic definitions
for FMER analysis and MATLAB library which is used in the text, that helps
final reader to apply the experiments in the real-world applications. We
believe that this book is suitable for students, researchers, and professionals
alike, who need to develop practical skills, along with a basic understanding
of the field. We expect that, after reading this book, the reader feels
comfortable with different key stages such as color and depth image processing,
color and depth image representation, classification, machine learning, facial
micro-expressions recognition, feature extraction and dimensionality reduction.
The book attempts to introduce a gentle introduction to the field of Facial
Micro Expressions Recognition (FMER) using Color and Depth images, with the aid
of MATLAB programming environment.Comment: This is the second edition of the boo
Bidirectionally Deformable Motion Modulation For Video-based Human Pose Transfer
Video-based human pose transfer is a video-to-video generation task that
animates a plain source human image based on a series of target human poses.
Considering the difficulties in transferring highly structural patterns on the
garments and discontinuous poses, existing methods often generate
unsatisfactory results such as distorted textures and flickering artifacts. To
address these issues, we propose a novel Deformable Motion Modulation (DMM)
that utilizes geometric kernel offset with adaptive weight modulation to
simultaneously perform feature alignment and style transfer. Different from
normal style modulation used in style transfer, the proposed modulation
mechanism adaptively reconstructs smoothed frames from style codes according to
the object shape through an irregular receptive field of view. To enhance the
spatio-temporal consistency, we leverage bidirectional propagation to extract
the hidden motion information from a warped image sequence generated by noisy
poses. The proposed feature propagation significantly enhances the motion
prediction ability by forward and backward propagation. Both quantitative and
qualitative experimental results demonstrate superiority over the
state-of-the-arts in terms of image fidelity and visual continuity. The source
code is publicly available at github.com/rocketappslab/bdmm.Comment: ICCV 202
Defending SDN against packet injection attacks using deep learning
The (logically) centralised architecture of the software-defined networks
makes them an easy target for packet injection attacks. In these attacks, the
attacker injects malicious packets into the SDN network to affect the services
and performance of the SDN controller and overflow the capacity of the SDN
switches. Such attacks have been shown to ultimately stop the network
functioning in real-time, leading to network breakdowns. There have been
significant works on detecting and defending against similar DoS attacks in
non-SDN networks, but detection and protection techniques for SDN against
packet injection attacks are still in their infancy. Furthermore, many of the
proposed solutions have been shown to be easily by-passed by simple
modifications to the attacking packets or by altering the attacking profile. In
this paper, we develop novel Graph Convolutional Neural Network models and
algorithms for grouping network nodes/users into security classes by learning
from network data. We start with two simple classes - nodes that engage in
suspicious packet injection attacks and nodes that are not. From these classes,
we then partition the network into separate segments with different security
policies using distributed Ryu controllers in an SDN network. We show in
experiments on an emulated SDN that our detection solution outperforms
alternative approaches with above 99\% detection accuracy on various types
(both old and new) of injection attacks. More importantly, our mitigation
solution maintains continuous functions of non-compromised nodes while
isolating compromised/suspicious nodes in real-time. All code and data are
publicly available for reproducibility of our results.Comment: 15 Pages, 15 Figure
Axisymmetry in Mechanical Engineering
The reprint is devoted to the phenomena associated with exact or approximate axial symmetry in different areas of technical physics and mechanical engineering science. How can the symmetry of the problem be used most efficiently for its analysis? Why is the symmetry broken or why is it still approximately retained? These and other questions are discussed based on systems from different fields of engineering
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