Energy
A Deep Neural Network for Unsupervised Anomaly Detection and Diagnosis in Multivariate Time Series Data
Zhang, Chuxu, Song, Dongjin, Chen, Yuncong, Feng, Xinyang, Lumezanu, Cristian, Cheng, Wei, Ni, Jingchao, Zong, Bo, Chen, Haifeng, Chawla, Nitesh V.
Nowadays, multivariate time series data are increasingly collected in various real world systems, e.g., power plants, wearable devices, etc. Anomaly detection and diagnosis in multivariate time series refer to identifying abnormal status in certain time steps and pinpointing the root causes. Building such a system, however, is challenging since it not only requires to capture the temporal dependency in each time series, but also need encode the inter-correlations between different pairs of time series. In addition, the system should be robust to noise and provide operators with different levels of anomaly scores based upon the severity of different incidents. Despite the fact that a number of unsupervised anomaly detection algorithms have been developed, few of them can jointly address these challenges. In this paper, we propose a Multi-Scale Convolutional Recurrent Encoder-Decoder (MSCRED), to perform anomaly detection and diagnosis in multivariate time series data. Specifically, MSCRED first constructs multi-scale (resolution) signature matrices to characterize multiple levels of the system statuses in different time steps. Subsequently, given the signature matrices, a convolutional encoder is employed to encode the inter-sensor (time series) correlations and an attention based Convolutional Long-Short Term Memory (ConvLSTM) network is developed to capture the temporal patterns. Finally, based upon the feature maps which encode the inter-sensor correlations and temporal information, a convolutional decoder is used to reconstruct the input signature matrices and the residual signature matrices are further utilized to detect and diagnose anomalies. Extensive empirical studies based on a synthetic dataset and a real power plant dataset demonstrate that MSCRED can outperform state-of-the-art baseline methods.
Slum Segmentation and Change Detection : A Deep Learning Approach
Maiya, Shishira R, Babu, Sudharshan Chandra
In some developing countries, slum residents make up for more than half of the population and lack reliable sanitation services, clean water, electricity, other basic services. Thus, slum rehabilitation and improvement is an important global challenge, and a significant amount of effort and resources have been put into this endeavor. These initiatives rely heavily on slum mapping and monitoring, and it is essential to have robust and efficient methods for mapping and monitoring existing slum settlements. In this work, we introduce an approach to segment and map individual slums from satellite imagery, leveraging regional convolutional neural networks for instance segmentation using transfer learning. In addition, we also introduce a method to perform change detection and monitor slum change over time. We show that our approach effectively learns slum shape and appearance, and demonstrates strong quantitative results, resulting in a maximum AP of 80.0.
An Adaptive Oversampling Learning Method for Class-Imbalanced Fault Diagnostics and Prognostics
Lin, Wenfang, Wu, Zhenyu, Ji, Yang
Data-driven fault diagnostics and prognostics suffers from class-imbalance problem in industrial systems and it raises challenges to common machine learning algorithms as it becomes difficult to learn the features of the minority class samples. Synthetic oversampling methods are commonly used to tackle these problems by generating the minority class samples to balance the distributions between majority and minority classes. However, many of oversampling methods are inappropriate that they cannot generate effective and useful minority class samples according to different distributions of data, which further complicate the process of learning samples. Thus, this paper proposes a novel adaptive oversampling technique: EM-based Weighted Minority Oversampling TEchnique (EWMOTE) for industrial fault diagnostics and prognostics. The methods comprises a weighted minority sampling strategy to identify hard-to-learn informative minority fault samples and Expectation Maximization (EM) based imputation algorithm to generate fault samples. To validate the performance of the proposed methods, experiments are conducted in two real datasets. The results show that the method could achieve better performance on not only binary class, but multi-class imbalance learning task in different imbalance ratios than other oversampling-based baseline models.
Measurement-based adaptation protocol with quantum reinforcement learning in a Rigetti quantum computer
Olivares-Sรกnchez, J., Casanova, J., Solano, E., Lamata, L.
We present an experimental realization of a measurement-based adaptation protocol with quantum reinforcement learning in a Rigetti cloud quantum computer. The experiment in this few-qubit superconducting chip faithfully reproduces the theoretical proposal, setting the first steps towards a semiautonomous quantum agent. This experiment paves the way towards quantum reinforcement learning with superconducting circuits.
Should you build or buy AI?
At VentureBeat's recent VB Summit event, I headed a session on whether enterprises should build or buy AI. Between comments from the panelists and a group of about 20 business leaders, a good decision tree emerged for how to answer this question. Given how important the question is, I wanted to share that decision tree more widely. As you can see, at the top of the tree is the question "Do you even need AI?" I believe AI can positively impact any and all businesses, so the correct answer should always be yes. The next question to ask is if AI is in your company's DNA.
Policy Optimization with Model-based Explorations
Pan, Feiyang, Cai, Qingpeng, Zeng, An-Xiang, Pan, Chun-Xiang, Da, Qing, He, Hualin, He, Qing, Tang, Pingzhong
Model-free reinforcement learning methods such as the Proximal Policy Optimization algorithm (PPO) have successfully applied in complex decision-making problems such as Atari games. However, these methods suffer from high variances and high sample complexity. On the other hand, model-based reinforcement learning methods that learn the transition dynamics are more sample efficient, but they often suffer from the bias of the transition estimation. How to make use of both model-based and model-free learning is a central problem in reinforcement learning. In this paper, we present a new technique to address the trade-off between exploration and exploitation, which regards the difference between model-free and model-based estimations as a measure of exploration value. We apply this new technique to the PPO algorithm and arrive at a new policy optimization method, named Policy Optimization with Model-based Explorations (POME). POME uses two components to predict the actions' target values: a model-free one estimated by Monte-Carlo sampling and a model-based one which learns a transition model and predicts the value of the next state. POME adds the error of these two target estimations as the additional exploration value for each state-action pair, i.e, encourages the algorithm to explore the states with larger target errors which are hard to estimate. We compare POME with PPO on Atari 2600 games, and it shows that POME outperforms PPO on 33 games out of 49 games.
Uncertainty quantification of molecular property prediction using Bayesian neural network models
Ryu, Seongok, Kwon, Yongchan, Kim, Woo Youn
In chemistry, deep neural network models have been increasingly utilized in a variety of applications such as molecular property predictions, novel molecule designs, and planning chemical reactions. Despite the rapid increase in the use of state-of-the-art models and algorithms, deep neural network models often produce poor predictions in real applications because model performance is highly dependent on the quality of training data. In the field of molecular analysis, data are mostly obtained from either complicated chemical experiments or approximate mathematical equations, and then quality of data may be questioned. In this paper, we quantify uncertainties of prediction using Bayesian neural networks in molecular property predictions. We estimate both model-driven and data-driven uncertainties, demonstrating the usefulness of uncertainty quantification as both a quality checker and a confidence indicator with the three experiments. Our results manifest that uncertainty quantification is necessary for more reliable molecular applications and Bayesian neural network models can be a practical approach.
Probabilistic Graphs for Sensor Data-driven Modelling of Power Systems at Scale
The growing complexity of the power grid, driven by increasing share of distributed energy resources and by massive deployment of intelligent internet-connected devices, requires new modelling tools for planning and operation. Physics-based state estimation models currently used for data filtering, prediction and anomaly detection are hard to maintain and adapt to the ever-changing complex dynamics of the power system. A data-driven approach based on probabilistic graphs is proposed, where custom non-linear, localised models of the joint density of subset of system variables can be combined to model arbitrarily large and complex systems. The graphical model allows to naturally embed domain knowledge in the form of variables dependency structure or local quantitative relationships. A specific instance where neural-network models are used to represent the local joint densities is proposed, although the methodology generalises to other model classes. Accuracy and scalability are evaluated on a large-scale data set representative of the European transmission grid.
Wi-Charge harnesses light to free Amazon Echo Dot and Google Home Mini smart speakers from power cords
A battery dock allows you to place the speaker anywhere in a room, not just in the proximity of an AC outlet. But those batteries will need recharging eventually, so most people who use them--myself included--end up leaving battery-docked smart speakers in the same places they'd be if they were AC-powered. A company called Wi-Charge claims it has a better solution: It has developed a battery-charging technology that harnesses the power of light. The power transmitter in this solution must be plugged into a wall, but the power receiver trickle-charges the battery in whatever device it's plugged into, keeping the battery forever topped off. Today, Wi-Charge announced new kits that work with Amazon Echo Dot and Google Home Mini smart speakers, so that the speakers can be placed anywhere in a room and operate without power cords.
KodaCloud CEO Explains How AI Improves Wi-Fi
The Adaptive & Intent-Based Networking Expo is less than three months away. So now would be great time to register for this new TMC event, which was designed to help business transformation, and business application and networking leaders and team members, learn more about how artificial intelligence- and machine learning-based solutions can help them automate network operations, address the data deluge, scale, secure their networks and applications, and become more agile and innovative. Wi-Fi networks are one area in which AI allows for marked improvements. Bernard Herscovici, founder and CEO of KodaCloud, will explain how during The Adaptive & Intent-Based Networking Expo panel "How to Use AI to Take Wi-Fi to the Next Level". Prior to founding KodaCloud in 2014, Bernard was vice president of Wi-Fi at Ericsson (News - Alert), and founder and CEO of BelAir Networks, a company that was sold to Ericsson in 2012.