An improved spectral extraction method for JWST/NIRSpec fixed slit observations

Abstract The James Webb Space Telescope is performing beyond our expectations. Its Near Infrared Spectrograph (NIRSpec) provides versatile spectroscopic capabilities in the 0.6-5.3 micrometre wavelength range, where a new window is opening for studying Trans-Neptunian objects in particular. We propose a spectral extraction method for NIRSpec fixed slit observations, with the aim of meeting the superior performance on the instrument with the most advanced data processing. We applied this method on the fixed slit dataset of the guaranteed-time observation program 1231, which targets Plutino 2003 AZ84.

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Bridging human concepts and computer vision for explainable face verification

Abstract With Artificial Intelligence (AI) influencing the decision-making process of sensitive applications such as Face Verification, it is fundamental to ensure the transparency, fairness, and accountability of decisions. Although Explainable Artificial Intelligence (XAI) techniques exist to clarify AI decisions, it is equally important to provide interpretability of these decisions to humans. In this paper, we present an approach to combine computer and human vision to increase the explanation’s interpretability of a face verification algorithm.

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How to compute the convex hull of a binary shape? A real-time algorithm to compute the convex hull of a binary shape

By Jonathan Fabrizio


In Journal of Real-Time Image Processing volume

Abstract In this article, we present an algorithm to compute the convex hull of a binary shape. Efficient algorithms to compute the convex hull of a set of points had been proposed long time ago. For a binary shape, the common practice is to rely on one of them: to compute the convex hull of binary shape, all pixels of the shape are first listed, and then the convex hull is computed on this list of points.

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Interactive and real-time typesetting for demonstration and experimentation: <span style="font-variant:small-caps;">ETAP</span>

By Didier Verna


In TUGboat

Abstract In general, typesetting experimentation is not a very practical thing to do. WYSIWYG typesetting systems are very reactive but do not offer highly configurable algorithms, and TeX, with its separate development / compilation / visualization phases, is not as interactive as its WYSIWYG competitors. Being able to experiment with typesetting algorithms interactively and in real-time is nevertheless desirable, for instance for demonstration purposes, or for rapid prototyping and debugging of new ideas.

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Dissecting ltlsynt

Abstract ltlsynt is a tool for synthesizing a reactive circuit satisfying a specification expressed as an LTL formula. ltlsynt generally follows a textbook approach: the LTL specification is translated into a parity game whose winning strategy can be seen as a Mealy machine modeling a valid controller. This article details each step of this approach, and presents various refinements integrated over the years. Some of these refinements are unique to ltlsynt: for instance, ltlsynt supports multiple ways to encode a Mealy machine as an AIG circuit, features multiple simplification algorithms for the intermediate Mealy machine, and bypasses the usual game-theoretic approach for some subclasses of LTL formulas in favor of more direct constructions.

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Discrete Morse functions and watersheds

By Gilles Bertrand, Nicolas Boutry, Laurent Najman


In Journal of Mathematical Imaging and Vision

Abstract Any watershed, when defined on a stack on a normal pseudomanifold of dimension d, is a pure (d-1)-subcomplex that satisfies a drop-of-water principle. In this paper, we introduce Morse stacks, a class of functions that are equivalent to discrete Morse functions. We show that the watershed of a Morse stack on a normal pseudomanifold is uniquely defined, and can be obtained with a linear-time algorithm relying on a sequence of collapses.

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Introducing PC n-manifolds and P-well-composedness in partially ordered sets

By Nicolas Boutry


In Journal of Mathematical Imaging and Vision

Abstract In discrete topology, discrete surfaces are well-known for their strong topological and regularity properties. Their definition is recursive, and checking if a poset is a discrete surface is tractable. Their applications are numerous: when domain unicoherence is ensured, they lead access to the tree of shapes, and then to filtering in the shape space (shapings); they also lead to Laplacian zero-crossing extraction, to brain tumor segmentation, and many other applications related to mathematical morphology.

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TTProfiler: Types and terms profile building for online cultural heritage knowledge graphs

By Lamine Diop, Béatrice Markhoff, Arnaud Soulet


In J. Comput. Cult. Herit.

Abstract As more and more knowledge graphs (KG) are published on the Web, there is a need for tools that show their content. This implies showing the schema-level patterns instantiated in the graph, but also the terms used to qualify its entities. In this article, we present a new profiling tool that we call TTprofiler. It shows the predicates that relate types in the KG, and also the terms present in this KG, because of their paramount importance in most KGs, especially in the Cultural Heritage (CH) domain.

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The Mealy-machine reduction functions of Spot

Abstract We present functions for reducing Mealy machines, initially detailed in our FORTE’22 article. These functions are now integrated into Spot 2.11.2, where they are used as part of the ltlsynt tool for reactive synthesis. Of course, since Spot is a library, these functions can also be used on their own, and we provide Python bindings for easy experiments. The reproducible capsule benchmarks these functions on Mealy machines from various sources, and compare them to the MeMin tool.

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