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Deep Synoptic Monte-Carlo Planning in Reconnaissance Blind Chess

Neural Information Processing Systems

This paper introduces deep synoptic Monte Carlo planning (DSMCP) for large imperfect information games. The algorithm constructs a belief state with an unweighted particle filter and plans via playouts that start at samples drawn from the belief state.


Deep Synoptic Monte-Carlo Planning in Reconnaissance Blind Chess

Neural Information Processing Systems

DSMCP is the basis of the program Penumbra, which won the official 2020 reconnaissance blind chess competition versus 33 other programs. This paper also evaluates algorithm variants that incorporate caution, paranoia, and a novel bandit algorithm. Furthermore, it audits the synopsis features used in Penumbra with per-bit saliency statistics.


Final infarct prediction in acute ischemic stroke

arXiv.org Artificial Intelligence

This article focuses on the control center of each human body: the brain. We will point out the pivotal role of the cerebral vasculature and how its complex mechanisms may vary between subjects. We then emphasize a specific acute pathological state, i.e., acute ischemic stroke, and show how medical imaging and its analysis can be used to define the treatment. We show how the core-penumbra concept is used in practice using mismatch criteria and how machine learning can be used to make predictions of the final infarct, either via deconvolution or convolutional neural networks.


Multi-input segmentation of damaged brain in acute ischemic stroke patients using slow fusion with skip connection

arXiv.org Artificial Intelligence

Time is a fundamental factor during stroke treatments. A fast, automatic approach that segments the ischemic regions helps treatment decisions. In clinical use today, a set of color-coded parametric maps generated from computed tomography perfusion (CTP) images are investigated manually to decide a treatment plan. We propose an automatic method based on a neural network using a set of parametric maps to segment the two ischemic regions (core and penumbra) in patients affected by acute ischemic stroke. Our model is based on a convolution-deconvolution bottleneck structure with multi-input and slow fusion. A loss function based on the focal Tversky index addresses the data imbalance issue. The proposed architecture demonstrates effective performance and results comparable to the ground truth annotated by neuroradiologists. A Dice coefficient of 0.81 for penumbra and 0.52 for core over the large vessel occlusion test set is achieved. The full implementation is available at: https://git.io/JtFGb.


Deep Synoptic Monte Carlo Planning in Reconnaissance Blind Chess

arXiv.org Artificial Intelligence

This paper introduces deep synoptic Monte Carlo planning (DSMCP) for large imperfect information games. The algorithm constructs a belief state with an unweighted particle filter and plans via playouts that start at samples drawn from the belief state. The algorithm accounts for uncertainty by performing inference on "synopses," a novel stochastic abstraction of information states. DSMCP is the basis of the program Penumbra, which won the official 2020 reconnaissance blind chess competition versus 33 other programs. This paper also evaluates algorithm variants that incorporate caution, paranoia, and a novel bandit algorithm. Furthermore, it audits the synopsis features used in Penumbra with per-bit saliency statistics.


Adversarially Trained Convolutional Neural Networks for Semantic Segmentation of Ischaemic Stroke Lesion using Multisequence Magnetic Resonance Imaging

arXiv.org Machine Learning

Ischaemic stroke is a medical condition caused by occlusion of blood supply to the brain tissue thus forming a lesion. A lesion is zoned into a core associated with irreversible necrosis typically located at the center of the lesion, while reversible hypoxic changes in the outer regions of the lesion are termed as the penumbra. Early estimation of core and penumbra in ischaemic stroke is crucial for timely intervention with thrombolytic therapy to reverse the damage and restore normalcy. Multisequence magnetic resonance imaging (MRI) is commonly employed for clinical diagnosis. However, a sequence singly has not been found to be sufficiently able to differentiate between core and penumbra, while a combination of sequences is required to determine the extent of the damage. The challenge, however, is that with an increase in the number of sequences, it cognitively taxes the clinician to discover symptomatic biomarkers in these images. In this paper, we present a data-driven fully automated method for estimation of core and penumbra in ischaemic lesions using diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) sequence maps of MRI. The method employs recent developments in convolutional neural networks (CNN) for semantic segmentation in medical images. In the absence of availability of a large amount of labeled data, the CNN is trained using an adversarial approach employing cross-entropy as a segmentation loss along with losses aggregated from three discriminators of which two employ relativistic visual Turing test. This method is experimentally validated on the ISLES-2015 dataset through three-fold cross-validation to obtain with an average Dice score of 0.82 and 0.73 for segmentation of penumbra and core respectively.


Self-driving cars can see around blind corners using this AI

#artificialintelligence

Artificial intelligence that allows self-driving cars to detect people and objects hidden around blind corners has been developed by researchers at MIT. The imaging system--dubbed CornerCameras--was built by AI researchers at MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL) for seeing around obstructions using standard camera technology. Using information about light reflections, MIT's artificial intelligence system is able to measure the speed and trajectory of hidden objects in real time using footage from smartphone cameras. "The technology has a range of applications, from firefighters finding people in burning buildings to self-driving cars detecting pedestrians in their blind spots," an MIT spokesperson tells Newsweek. "What's impressive is that this approach works using footage from a smartphone camera, such as an iPhone 8." The artificial intelligence system can be used on footage filmed with a smartphone.


CornerCamera made at MIT lets you see through walls

Daily Mail - Science & tech

Seeing through walls and spying around corners may sound like a superpower, but advances in technology are now making this a reality. A system, dubbed CornerCameras, developed at MIT, uses smartphone cameras to peer round corners and check what's on the other side. The ability to see around obstructions could help firefighters find people in burning buildings or enable self-driving cars to detect pedestrians in their blind spots. Seeing through walls may sound like a superpower, but advances in technology are now making this a reality. A system, dubbed CornerCameras, developed at MIT, uses smartphone cameras to peer round corners and check what's on the other side Most approaches for seeing around obstacles involve special lasers. Researchers shine cameras on specific points that are visible to both the observable and hidden scene, and then measure how long it takes for the light to return.