Oceania
Learning to extrapolate using continued fractions: Predicting the critical temperature of superconductor materials
Moscato, Pablo, Haque, Mohammad Nazmul, Huang, Kevin, Sloan, Julia, de Oliveira, Jon C.
In Artificial Intelligence we often seek to identify an unknown target function of many variables $y=f(\mathbf{x})$ giving a limited set of instances $S=\{(\mathbf{x^{(i)}},y^{(i)})\}$ with $\mathbf{x^{(i)}} \in D$ where $D$ is a domain of interest. We refer to $S$ as the training set and the final quest is to identify the mathematical model that approximates this target function for new $\mathbf{x}$; with the set $T=\{ \mathbf{x^{(j)}} \} \subset D$ with $T \neq S$ (i.e. thus testing the model generalisation). However, for some applications, the main interest is approximating well the unknown function on a larger domain $D'$ that contains $D$. In cases involving the design of new structures, for instance, we may be interested in maximizing $f$; thus, the model derived from $S$ alone should also generalize well in $D'$ for samples with values of $y$ larger than the largest observed in $S$. In that sense, the AI system would provide important information that could guide the design process, e.g., using the learned model as a surrogate function to design new lab experiments. We introduce a method for multivariate regression based on iterative fitting of a continued fraction by incorporating additive spline models. We compared it with established methods such as AdaBoost, Kernel Ridge, Linear Regression, Lasso Lars, Linear Support Vector Regression, Multi-Layer Perceptrons, Random Forests, Stochastic Gradient Descent and XGBoost. We tested the performance on the important problem of predicting the critical temperature of superconductors based on physical-chemical characteristics.
Prediction in ungauged regions with sparse flow duration curves and input-selection ensemble modeling
Feng, Dapeng, Lawson, Kathryn, Shen, Chaopeng
While long short-term memory (LSTM) models have demonstrated stellar performance with streamflow predictions, there are major risks in applying these models in contiguous regions with no gauges, or predictions in ungauged regions (PUR) problems. However, softer data such as the flow duration curve (FDC) may be already available from nearby stations, or may become available. Here we demonstrate that sparse FDC data can be migrated and assimilated by an LSTM-based network, via an encoder. A stringent region-based holdout test showed a median Kling-Gupta efficiency (KGE) of 0.62 for a US dataset, substantially higher than previous state-of-the-art global-scale ungauged basin tests. The baseline model without FDC was already competitive (median KGE 0.56), but integrating FDCs had substantial value. Because of the inaccurate representation of inputs, the baseline models might sometimes produce catastrophic results. However, model generalizability was further meaningfully improved by compiling an ensemble based on models with different input selections.
Combining GANs and AutoEncoders for Efficient Anomaly Detection
Carrara, Fabio, Amato, Giuseppe, Brombin, Luca, Falchi, Fabrizio, Gennaro, Claudio
In this work, we propose CBiGAN -- a novel method for anomaly detection in images, where a consistency constraint is introduced as a regularization term in both the encoder and decoder of a BiGAN. Our model exhibits fairly good modeling power and reconstruction consistency capability. We evaluate the proposed method on MVTec AD -- a real-world benchmark for unsupervised anomaly detection on high-resolution images -- and compare against standard baselines and state-of-the-art approaches. Experiments show that the proposed method improves the performance of BiGAN formulations by a large margin and performs comparably to expensive state-of-the-art iterative methods while reducing the computational cost. We also observe that our model is particularly effective in texture-type anomaly detection, as it sets a new state of the art in this category. Our code is available at https://github.com/fabiocarrara/cbigan-ad/.
Creator Of Amazon's Zoox Robotaxi Unit Has A New Self-Driving Startup
HYPR is testing its self-learning autonomous driving system in a modified Daimler Smart Car. As Zoox, the secretive robotaxi developer recently acquired by Amazon, gets ready to unveil its futuristic fleet vehicle, its former CEO who dreamed up the company is re-emerging with a new startup that's designing AI-enabled software he hopes will allow cars to "teach themselves" to drive. Early-stage HYPR, created by Zoox cofounder Tim Kentley Klay, says it's using reinforcement learning, a branch of machine learning that utilizes a reward-based approach, to train driving algorithms dynamically–ideally with no need for direct human instruction or supervision. The Alameda, California-based startup has raised a $10 million seed round and begun testing its approach with a modified Daimler Smart Car. Backers include R7 Ventures and Australian billionaire Andrew Forrest.
Transport for NSW trials machine learning to detect crash blackspots
Transport for NSW has built a proof-of-concept using machine learning technology from Microsoft to identify potentially dangerous traffic intersections and fast-track remediation works. The'dangerous intersections' proof-of-concept, which took place last year, analysed telematic data collected from 50 vehicles travelling on Wollongong's roads over a 10-month period. The data – sent from the vehicles at a rate of 25 records a second – was used to pinpoint five previously unknown blackspots, with the two highest-risk now slated for upgrades later this financial year. TfNSW's data discovery program lead Julianna Bodzan came up with the idea while driving down the Mount Ousley descent on the Princes Highway – a notorious, four-and-a-half kilometre stretch of road leading into North Wollongong. She said the telematics data collected from the vehicles was compared with crash data from known blackspots to discern whether or not other intersections in the coastal city were potentially risky.
OrgMining 2.0: A Novel Framework for Organizational Model Mining from Event Logs
Yang, Jing, Ouyang, Chun, van der Aalst, Wil M. P., ter Hofstede, Arthur H. M., Yu, Yang
Providing appropriate structures around human resources can streamline operations and thus facilitate the competitiveness of an organization. To achieve this goal, modern organizations need to acquire an accurate and timely understanding of human resource grouping while faced with an ever-changing environment. The use of process mining offers a promising way to help address the need through utilizing event log data stored in information systems. By extracting knowledge about the actual behavior of resources participating in business processes from event logs, organizational models can be constructed, which facilitate the analysis of the de facto grouping of human resources relevant to process execution. Nevertheless, open research gaps remain to be addressed when applying the state-of-the-art process mining to analyze resource grouping. For one, the discovery of organizational models has only limited connections with the context of process execution. For another, a rigorous solution that evaluates organizational models against event log data is yet to be proposed. In this paper, we aim to tackle these research challenges by developing a novel framework built upon a richer definition of organizational models coupling resource grouping with process execution knowledge. By introducing notions of conformance checking for organizational models, the framework allows effective evaluation of organizational models, and therefore provides a foundation for analyzing and improving resource grouping based on event logs. We demonstrate the feasibility of this framework by proposing an approach underpinned by the framework for organizational model discovery, and also conduct experiments on real-life event logs to discover and evaluate organizational models.
Modular Structures and Atomic Decomposition in Ontologies
Del Vescovo, Chiara (BBC) | Horridge, Matthew (Stanford University) | Parsia, Bijan (University of Manchester) | Sattler, Uli (University of Manchester) | Schneider, Thomas (University of Bremen) | Zhao, Haoruo (University of Manchester)
With the growth of ontologies used in diverse application areas, the need for module extraction and modularisation techniques has risen. The notion of the modular structure of an ontology, which comprises a suitable set of base modules together with their logical dependencies, has the potential to help users and developers in comprehending, sharing, and maintaining an ontology. We have developed a new modular structure, called atomic decomposition (AD), which is based on modules that provide strong logical properties, such as locality-based modules. In this article, we present the theoretical foundations of AD, review its logical and computational properties, discuss its suitability as a modular structure, and report on an experimental evaluation of AD. In addition, we discuss the concept of a modular structure in ontology engineering and provide a survey of existing decomposition approaches.
Artificial Intelligence for COVID-19 Detection -- A state-of-the-art review
Sarosh, Parsa, Parah, Shabir A., Mansur, Romany F, Bhat, G. M.
The emergence of COVID-19 has necessitated many efforts by the scientific community for its proper management. An urgent clinical reaction is required in the face of the unending devastation being caused by the pandemic. These efforts include technological innovations for improvement in screening, treatment, vaccine development, contact tracing and, survival prediction. The use of Deep Learning (DL) and Artificial Intelligence (AI) can be sought in all of the above-mentioned spheres. This paper aims to review the role of Deep Learning and Artificial intelligence in various aspects of the overall COVID-19 management and particularly for COVID-19 detection and classification. The DL models are developed to analyze clinical modalities like CT scans and X-Ray images of patients and predict their pathological condition. A DL model aims to detect the COVID-19 pneumonia, classify and distinguish between COVID-19, Community-Acquired Pneumonia (CAP), Viral and Bacterial pneumonia, and normal conditions. Furthermore, sophisticated models can be built to segment the affected area in the lungs and quantify the infection volume for a better understanding of the extent of damage. Many models have been developed either independently or with the help of pre-trained models like VGG19, ResNet50, and AlexNet leveraging the concept of transfer learning. Apart from model development, data preprocessing and augmentation are also performed to cope with the challenge of insufficient data samples often encountered in medical applications. It can be evaluated that DL and AI can be effectively implemented to withstand the challenges posed by the global emergency
Advancements of federated learning towards privacy preservation: from federated learning to split learning
Thapa, Chandra, Chamikara, M. A. P., Camtepe, Seyit A.
In the distributed collaborative machine learning (DCML) paradigm, federated learning (FL) recently attracted much attention due to its applications in health, finance, and the latest innovations such as industry 4.0 and smart vehicles. FL provides privacy-by-design. It trains a machine learning model collaboratively over several distributed clients (ranging from two to millions) such as mobile phones, without sharing their raw data with any other participant. In practical scenarios, all clients do not have sufficient computing resources (e.g., Internet of Things), the machine learning model has millions of parameters, and its privacy between the server and the clients while training/testing is a prime concern (e.g., rival parties). In this regard, FL is not sufficient, so split learning (SL) is introduced. SL is reliable in these scenarios as it splits a model into multiple portions, distributes them among clients and server, and trains/tests their respective model portions to accomplish the full model training/testing. In SL, the participants do not share both data and their model portions to any other parties, and usually, a smaller network portion is assigned to the clients where data resides. Recently, a hybrid of FL and SL, called splitfed learning, is introduced to elevate the benefits of both FL (faster training/testing time) and SL (model split and training). Following the developments from FL to SL, and considering the importance of SL, this chapter is designed to provide extensive coverage in SL and its variants. The coverage includes fundamentals, existing findings, integration with privacy measures such as differential privacy, open problems, and code implementation.