Europe
Assessing the Utility of Weather Data for Photovoltaic Power Prediction
Zafarani, Reza, Eftekharnejad, Sara, Patel, Urvi
Photovoltaic systems have been widely deployed in recent times to meet the increased electricity demand as an environmental-friendly energy source. The major challenge for integrating photovoltaic systems in power systems is the unpredictability of the solar power generated. In this paper, we analyze the impact of having access to weather information for solar power generation prediction and find weather information that can help best predict photovoltaic power.
Unsupervised Anomaly Detection via Variational Auto-Encoder for Seasonal KPIs in Web Applications
Xu, Haowen, Chen, Wenxiao, Zhao, Nengwen, Li, Zeyan, Bu, Jiahao, Li, Zhihan, Liu, Ying, Zhao, Youjian, Pei, Dan, Feng, Yang, Chen, Jie, Wang, Zhaogang, Qiao, Honglin
To ensure undisrupted business, large Internet companies need to closely monitor various KPIs (e.g., Page Views, number of online users, and number of orders) of its Web applications, to accurately detect anomalies and trigger timely troubleshooting/mitigation. However, anomaly detection for these seasonal KPIs with various patterns and data quality has been a great challenge, especially without labels. In this paper, we proposed Donut, an unsupervised anomaly detection algorithm based on VAE. Thanks to a few of our key techniques, Donut greatly outperforms a state-of-arts supervised ensemble approach and a baseline VAE approach, and its best F-scores range from 0.75 to 0.9 for the studied KPIs from a top global Internet company. We come up with a novel KDE interpretation of reconstruction for Donut, making it the first VAE-based anomaly detection algorithm with solid theoretical explanation.
Imitation networks: Few-shot learning of neural networks from scratch
Kimura, Akisato, Ghahramani, Zoubin, Takeuchi, Koh, Iwata, Tomoharu, Ueda, Naonori
In this paper, we propose imitation networks, a simple but effective method for training neural networks with a limited amount of training data. Our approach inherits the idea of knowledge distillation that transfers knowledge from a deep or wide reference model to a shallow or narrow target model. The proposed method employs this idea to mimic predictions of reference estimators that are much more robust against overfitting than the network we want to train. Different from almost all the previous work for knowledge distillation that requires a large amount of labeled training data, the proposed method requires only a small amount of training data. Instead, we introduce pseudo training examples that are optimized as a part of model parameters. Experimental results for several benchmark datasets demonstrate that the proposed method outperformed all the other baselines, such as naive training of the target model and standard knowledge distillation.
Blind Source Separation Using Mixtures of Alpha-Stable Distributions
Keriven, Nicolas, Deleforge, Antoine, Liutkus, Antoine
We propose a new blind source separation algorithm based on mixtures of alpha-stable distributions. Complex symmetric alpha-stable distributions have been recently showed to better model audio signals in the time-frequency domain than classical Gaussian distributions thanks to their larger dynamic range. However, inference of these models is notoriously hard to perform because their probability density functions do not have a closed-form expression in general. Here, we introduce a novel method for estimating mixture of alpha-stable distributions based on characteristic function matching. We apply this to the blind estimation of binary masks in individual frequency bands from multichannel convolutive audio mixes. We show that the proposed method yields better separation performance than Gaussian-based binary-masking methods.
Information-Theoretic Representation Learning for Positive-Unlabeled Classification
Sakai, Tomoya, Niu, Gang, Sugiyama, Masashi
In real-world applications, it is conceivable that only positive and unlabeled (PU) data are available for training a classifier. For instance, in land-cover image classification, images of urban regions can be easily labeled, while images of non-urban regions are difficult to annotate due to high diversity of non-urban regions containing, e.g., forest, seas, grasses, and soil (Li et al., 2011). To cope with such situations, PU classification has been actively studied (Letouzey et al., 2000; Elkan and Noto, 2008; du Plessis et al., 2015), and the state-of-the-art method allows us to systematically train deep neural networks only from PU data (Kiryo et al., 2017). However, existing PU classification methods typically require an estimate of the class-prior probability, and their performance is sensitive to the quality of class-prior estimation (Kiryo et al., 2017). Although various class-prior estimation methods from PU data have been proposed so far (du Plessis and Sugiyama, 2014; Ramaswamy et al., 2016; Jain et al., 2016; du Plessis et al., 2017; Northcutt et al., 2017), accurate estimation of the class-prior is still highly challenging particularly for high-dimensional data.
Deep Convolutional Neural Networks on Cartoon Functions
Grohs, Philipp, Wiatowski, Thomas, Bölcskei, Helmut
Wiatowski and B\"olcskei, 2015, proved that deformation stability and vertical translation invariance of deep convolutional neural network-based feature extractors are guaranteed by the network structure per se rather than the specific convolution kernels and non-linearities. While the translation invariance result applies to square-integrable functions, the deformation stability bound holds for band-limited functions only. Many signals of practical relevance (such as natural images) exhibit, however, sharp and curved discontinuities and are, hence, not band-limited. The main contribution of this paper is a deformation stability result that takes these structural properties into account. Specifically, we establish deformation stability bounds for the class of cartoon functions introduced by Donoho, 2001.
Stochastic quasi-Newton with adaptive step lengths for large-scale problems
We provide a numerically robust and fast method capable of exploiting the local geometry when solving large-scale stochastic optimisation problems. Our key innovation is an auxiliary variable construction coupled with an inverse Hessian approximation computed using a receding history of iterates and gradients. It is the Markov chain nature of the classic stochastic gradient algorithm that enables this development. The construction offers a mechanism for stochastic line search adapting the step length. We numerically evaluate and compare against current state-of-the-art with encouraging performance on real-world benchmark problems where the number of observations and unknowns is in the order of millions.
AI listens in on emergency calls to diagnose cardiac arrest
IF YOU dial the emergency services in Denmark, soon you won't just get a human operator –an artificially intelligent assistant will be listening in too. Developed by start-up Corti, the system kicks into action when someone dials 112 in Copenhagen, then it starts listening for signs of a possible cardiac arrest. To do this, it first uses speech-recognition software to transcribe what is being said before analysing the text. Once it is confident of a diagnosis, it flashes an alert on the screen for the operator to see. …
Global Artificial Intelligence (AI) Market Outlook 2024: Global Opportunity and Demand Analysis, Market Forecast, 2016-2024– WiseGuyReports
Global Artificial Intelligence (AI) Market Outlook Market Overview In the era of digitalization and rapidly changing technology, Artificial intelligence technology is one the fastest evolving technology across the globe. Further this technology has vast applications in various sectors like healthcare and manufacturing. Artificial intelligence has potential to lift various industries by reducing the human effort and increasing productivity. The AI technology will transform the functionality of various sectors such as agriculture, Industrial, BFSI, Healthcare among others by providing ease to consumers and the users. Artificial intelligence consists of various technologies such as natural language processing, quarrying, deep learning etc which can be implemented in various applications. AI technologies increase the efficiency of organization and complete tasks efficiently on the back of systematic inputs in the system.
Infographic: What are customers' chief chatbot complaints?
Chatbot adoption continues to rise, but new research reveals that as they become a more familiar interaction point for consumers there are a number of common complaints that are surfacing. Research conducted by Chatbots.org in conjunction with eGain, interiewed 3,000 consumers across the UK and US who had used a chatbot for customer service in the prior 12 months, asking them to rate them for customer service, and to state what in particular about chatbots annoyed them.