Results for "Maribel Ortego"

total 52took 0.07s
Multivariate statistical modelling of future marine stormsMar 13 2019Extreme events, such as wave-storms, need to be characterized for coastal infrastructure design purposes. Such description should contain information on both the univariate behaviour and the joint-dependence of storm-variables. These two aspects have ... More
Proceedings Ninth International Workshop on Reduction Strategies in Rewriting and ProgrammingJan 26 2010This volume contains selected papers presented at the 9th International Workshop on Reduction Strategies in Rewriting and Programming, WRS2009, which was held in Brasilia on the 28th June 2009, associated to RTA 2009 (the 20th International Conference ... More
Proceedings 24th International Workshop on UnificationDec 21 2010This volume contains selected papers presented at the 24th International Workshop on Unification, UNIF2010, which was held in Edinburgh on the 14th July 2010, as part of FLoC 2010 (Federated Logic Conferences).
Higher-order port-graph rewritingNov 17 2012The biologically inspired framework of port-graphs has been successfully used to specify complex systems. It is the basis of the PORGY modelling tool. To facilitate the specification of proof normalisation procedures via graph rewriting, in this paper ... More
Proceedings Tenth International Workshop on Computing with Terms and GraphsFeb 05 2019This volume contains a selection of the papers presented at TERMGRAPH 2018, the tenth edition of the international workshop on computing with terms and graphs. Graphs, and graph transformation systems, are used in many areas within Computer Science: to ... More
Strategic programming on graph rewriting systemsDec 27 2010We describe a strategy language to control the application of graph rewriting rules, and show how this language can be used to write high-level declarative programs in several application areas. This language is part of a graph-based programming tool ... More
Lie tori of type B_2 and graded-simple Jordan structures covered by a triangleAug 01 2011We classify two classes of B_2-graded Lie algebras which have a second compatible grading by an abelian group A: (a) graded-simple Lie algebras for A torsion-free and (b) division-A-graded Lie algebras. Our results describe the centreless cores of a class ... More
Labelled Lambda-calculi with Explicit Copy and EraseMar 29 2010We present two rewriting systems that define labelled explicit substitution lambda-calculi. Our work is motivated by the close correspondence between Levy's labelled lambda-calculus and paths in proof-nets, which played an important role in the understanding ... More
Graph Creation, Visualisation and TransformationMar 23 2010We describe a tool to create, edit, visualise and compute with interaction nets - a form of graph rewriting systems. The editor, called GraphPaper, allows users to create and edit graphs and their transformation rules using an intuitive user interface. ... More
From nominal to higher-order rewriting and back againSep 17 2015Dec 11 2015We present a translation function from nominal rewriting systems (NRSs) to combinatory reduction systems (CRSs), transforming closed nominal rules and ground nominal terms to CRSs rules and terms, respectively, while preserving the rewriting relation. ... More
Static Enforcement of Role-Based Access ControlSep 09 2014We propose a new static approach to Role-Based Access Control (RBAC) policy enforcement. The static approach we advocate includes a new design methodology, for applications involving RBAC, which integrates the security requirements into the system's architecture. ... More
Assembling the Proofs of Ordered Model TransformationsFeb 21 2013In model-driven development, an ordered model transformation is a nested set of transformations between source and target classes, in which each transformation is governed by its own pre and post- conditions, but structurally dependent on its parent. ... More
Proceedings Fourth International Workshop on LinearityJan 17 2017This volume contains the papers presented at LINEARITY 2016, the Fourth International Workshop on Linearity, held on June 26, 2016 in Porto, Portugal. The workshop was a one-day satellite event of FSCD 2016, the first International Conference on Formal ... More
Closed nominal rewriting and efficiently computable nominal algebra equalitySep 14 2010We analyse the relationship between nominal algebra and nominal rewriting, giving a new and concise presentation of equational deduction in nominal theories. With some new results, we characterise a subclass of equational theories for which nominal rewriting ... More
Classification of the Absolute-Valued Algebras with Left-Unit Satisfying x2(x2)2 = (x2)2x2Sep 01 2011We show that every absolute-valued algebra with left-unit satisfying (x2; x2; x2) = 0 is finite-dimensional of degree at most 4: Next, we determine such an algebras. In addition to the already known algebras R; C; \astC; H; \astH; \astH(i; 1); O; \astO; ... More
TokTrack: A Complete Token Provenance and Change Tracking Dataset for the English WikipediaMar 23 2017We present a dataset that contains every instance of all tokens (~ words) ever written in undeleted, non-redirect English Wikipedia articles until October 2016, in total 13,545,349,787 instances. Each token is annotated with (i) the article revision it ... More
Strategic Port Graph Rewriting: An Interactive Modelling and Analysis FrameworkJul 30 2014We present strategic portgraph rewriting as a basis for the implementation of visual modelling and analysis tools. The goal is to facilitate the specification, analysis and simulation of complex systems, using port graphs. A system is represented by an ... More
A coordinate ascent method for solving semidefinite relaxations of non-convex quadratic integer programsMar 08 2016We present a coordinate ascent method for a class of semidefinite programming problems that arise in non-convex quadratic integer optimization. These semidefinite programs are characterized by a small total number of active constraints and by low-rank ... More
Class of Eistein-Maxwell DilatonsAug 28 2000The functional potential formalism is used to analyze stationary axisymmetric spaces in the Einstein-Maxwell-Dilaton theory. Performing a Legendre transformation, a ``Hamiltonian''is obtained, which allows to rewrite the dynamical equations in terms of ... More
General dynamic recovery for compensating CSPApr 01 2014Compensation is a technique to roll-back a system to a consistent state in case of failure. Recovery mechanisms for compensating calculi specify the order of execution of compensation sequences. Dynamic recovery means that the order of execution is determined ... More
Bigraphical NetsFeb 26 2013Interaction nets are a graphical model of computation, which has been used to define efficient evaluators for functional calculi, and specifically lambda calculi with patterns. However, the flat structure of interaction nets forces pattern matching and ... More
Robust Estimation for Two-Dimensional Autoregressive Processes Based on Bounded Innovation Propagation RepresentationsJul 07 2018Robust methods have been a successful approach to deal with contaminations and noises in image processing. In this paper, we introduce a new robust method for two-dimensional autoregressive models. Our method, called BMM-2D, relies on representing a two-dimensional ... More
SDP-based branch-and-bound for non-convex quadratic integer optimizationJan 29 2019Semidefinite programming (SDP) relaxations have been intensively used for solving discrete quadratic optimization problems, in particular in the binary case. For the general non-convex integer case with box constraints, the branch-and-bound algorithm ... More
A new graphical calculus of proofsFeb 14 2011We offer a simple graphical representation for proofs of intuitionistic logic, which is inspired by proof nets and interaction nets (two formalisms originating in linear logic). This graphical calculus of proofs inherits good features from each, but is ... More
Attributed Hierarchical Port Graphs and ApplicationsFeb 19 2018We present attributed hierarchical port graphs (AHP) as an extension of port graphs that aims at facilitating the design of modular port graph models for complex systems. AHP consist of a number of interconnected layers, where each layer defines a port ... More
Origin and evolution of ferroelectricity in the layered rare-earth-titanate, $R_2$Ti$_2$O$_{7}$, Lichtenberg phasesMar 28 2019We report a systematic first-principles study based on density functional theory (DFT) of the structural and ferroelectric properties of the $R_2$Ti$_2$O$_{7}$ perovskite-related oxides with $R=$ La, Ce, Pr, and Nd. We show that, in all cases, the ferroelectric ... More
On guiding video object segmentationApr 25 2019This paper presents a novel approach for segmenting moving objects in unconstrained environments using guided convolutional neural networks. This guiding process relies on foreground masks from independent algorithms (i.e. state-of-the-art algorithms) ... More
Unsupervised label noise modeling and loss correctionApr 25 2019Despite being robust to small amounts of label noise, convolutional neural networks trained with stochastic gradient methods have been shown to easily fit random labels. When there are a mixture of correct and mislabelled targets, networks tend to fit ... More
On Nominal Syntax and Permutation Fixed PointsFeb 22 2019We propose a new axiomatisation of the alpha-equivalence relation for nominal terms, based on a primitive notion of fixed-point constraint. We show that the standard freshness relation between atoms and terms can be derived from the more primitive notion ... More
Ab initio study of the ferroelectric strain dependence and 180$^\circ$ domain walls in the barium metal fluorides BaMgF$_4$ and BaZnF$_4$Oct 30 2015Nov 02 2015We investigate the strain dependence of the ferroelectric polarization and the structure of the ferroelectric domain walls in the layered perovskite-related barium fluorides, BaMF$_4$ (M=Mg, Zn). The unusual "geometric ferroelectricity" in these materials ... More
Efficient technique for computational design of thermoelectric materialsOct 25 2016Efficient thermoelectric materials are highly desirable, and the quest for finding them has intensified as they could be promising alternatives to fossil energy sources. Here we present a general first-principles approach to predict, in multicomponent ... More
Efficient technique for computational design of thermoelectric materialsOct 25 2016Oct 07 2017Efficient thermoelectric materials are highly desirable, and the quest for finding them has intensified as they could be promising alternatives to fossil energy sources. Here we present a general first-principles approach to predict, in multicomponent ... More
Cosmic acceleration from topological considerations II: Fiber bundlesJan 10 2019In this work we study an alternative topological model for explaining the observed acceleration of space-time, we answer the question of whether this acceleration could be a consequence of the topology of the universe. For doing that, we propose that ... More
Linear RecursionJan 19 2010Jan 14 2011We show that the full PCF language can be encoded in Lrec, a linear lambda-calculus extended with numbers, pairs and an unbounded recursor that preserves the syntactic linearity of the calculus. Thus, Lrec is a Turing complete extension of the linear ... More
Inference of Phylogenetic Trees from the Knowledge of Rare Evolutionary EventsDec 29 2016Jun 14 2017Rare events have played an increasing role in molecular phylogenetics as potentially homoplasy-poor characters.In this contribution we analyze the phylogenetic information content from a combinatorial point of view by consid-ering the binary relation ... More
Rotating 5D-Kaluza-Klein Space-Times from Invariant TransformationsJan 14 2000Using invariant transformations of the five-dimensional Kaluza-Klein (KK) field equations, we find a series of formulae to derive axial symmetric stationary exact solutions of the KK theory starting from static ones. The procedure presented in this work ... More
Linear RecursionJan 19 2010Nov 25 2016We define two extensions of the typed linear lambda-calculus that yield minimal Turing-complete systems. The extensions are based on unbounded recursion in one case, and bounded recursion with minimisation in the other. We show that both approaches are ... More
Elementary Deduction Problem for Locally Stable Theories with Normal FormsMar 29 2013We present an algorithm to decide the intruder deduction problem (IDP) for a class of locally stable theories enriched with normal forms. Our result relies on a new and efficient algorithm to solve a restricted case of higher-order associative-commutative ... More
PORGY: Strategy-Driven Interactive Transformation of GraphsFeb 14 2011This paper investigates the use of graph rewriting systems as a modelling tool, and advocates the embedding of such systems in an interactive environment. One important application domain is the modelling of biochemical systems, where states are represented ... More
Nominal C-UnificationSep 15 2017Nominal unification is an extension of first-order unification that takes into account the \alpha-equivalence relation generated by binding operators, following the nominal approach. We propose a sound and complete procedure for nominal unification with ... More
Proceedings Joint International Workshop on Linearity & Trends in Linear Logic and ApplicationsApr 12 2019This volume contains a selection of papers presented at Linearity/TLLA 2018: Joint Linearity and TLLA workshops (part of FLOC 2018) held on July 7-8, 2018 in Oxford. Linearity has been a key feature in several lines of research in both theoretical and ... More
RDF-Hunter: Automatically Crowdsourcing the Execution of Queries Against RDF Data SetsMar 10 2015In the last years, a large number of RDF data sets has become available on the Web. However, due to the semi-structured nature of RDF data, missing values affect answer completeness of queries that are posed against this data. To overcome this limitation, ... More
1st International Workshop on Distributed Evolutionary Computation in Informal EnvironmentsJun 01 2011Jun 02 2011Online conference proceedings for the IWDECIE workshop, taking place in New Orleans on June 5th, 2011. The workshop focuses on non-conventional implementations of bioinspired algorithms and its conceptual implications.
Spiders can be recognized by counting their legsNov 08 2014Spiders are arthropods that can be distinguished from their closest relatives, the insects, by counting their legs. Spiders have 8, insects just 6. Spider graphs are a very restricted class of graphs that naturally appear in the context of cograph editing. ... More
Cloud-based Evolutionary Algorithms: An algorithmic studyMay 31 2011After a proof of concept using Dropbox(tm), a free storage and synchronization service, showed that an evolutionary algorithm using several dissimilar computers connected via WiFi or Ethernet had a good scaling behavior in terms of evaluations per second, ... More
Evidence for a pressure-induced spin transition in olivine-type LiFePO$_{4}$ triphyliteJan 09 2018Jan 16 2018We present a combination of first-principles and experimental results regarding the structural and magnetic properties of olivine-type LiFePO$_4$ under pressure. Our investigations indicate that the starting $Pbnm$ phase of LiFePO$_4$ persists up to 70 ... More
A unified approach to Fiedler-like pencils via strong block minimal bases pencilsNov 22 2016The standard way of solving the polynomial eigenvalue problem associated with a matrix polynomial is to embed the matrix polynomial into a matrix pencil, transforming the problem into an equivalent generalized eigenvalue problem. Such pencils are known ... More
Explicit block-structures for block-symmetric Fiedler-like pencilsNov 16 2017In the last decade, there has been a continued effort to produce families of strong linearizations of a matrix polynomial $P(\lambda)$, regular and singular, with good properties. As a consequence of this research, families such as the family of Fiedler ... More
Concurrent and Accurate RNA Sequencing on Multicore PlatformsApr 02 2013In this paper we introduce a novel parallel pipeline for fast and accurate mapping of RNA sequences on servers equipped with multicore processors. Our software, named HPG-Aligner, leverages the speed of the Burrows-Wheeler Transform to map a large number ... More
Best Match Graphs and Reconciliation of Gene Trees with Species TreesApr 26 2019A wide variety of problems in computational biology, most notably the assessment of orthology, are solved with the help of reciprocal best matches. Using an evolutionary definition of best matches that captures the intuition behind the concept we clarify ... More
Best Match Graphs and Reconciliation of Gene Trees with Species TreesApr 26 2019May 15 2019A wide variety of problems in computational biology, most notably the assessment of orthology, are solved with the help of reciprocal best matches. Using an evolutionary definition of best matches that captures the intuition behind the concept we clarify ... More
Best Match GraphsMar 29 2018Dec 14 2018Best match graphs arise naturally as the first processing intermediate in algorithms for orthology detection. Let $T$ be a phylogenetic (gene) tree $T$ and $\sigma$ an assignment of leaves of $T$ to species. The best match graph $(G,\sigma)$ is a digraph ... More