Magnetization reversal in amorphous Fe/Dy multilayers: a Monte Carlo study

The Monte Carlo method in the canonical ensemble is used to investigate magnetization reversal in amorphous transition metal - rare earth multilayers. Our study is based on a model containing diluted clusters which exhibit an effective uniaxial anisotropy in competition with random magnetic anisotropy in the matrix. We simulate hysteresis loops for an abrupt profile and a diffuse one obtained from atom probe tomography analyses. Our results evidence that the atom probe tomography profile favors perpendicular magnetic anisotropy in agreement with magnetic measurements. Moreover, the hysteresis loops calculated at several temperatures qualitatively agree with the experimental ones

Visibly Pushdown Transducers with Well-nested Outputs

Visibly pushdown transducers (VPTs) are visibly pushdown automata extended with outputs. They have been introduced to model transformations of nested words, i.e. words with a call/return structure. When outputs are also structured and well nested words, VPTs are a natural formalism to express tree transformations evaluated in streaming. We prove the class of VPTs with well-nested outputs to be decidable in PTIME. Moreover, we show that this class is closed under composition and that its type-checking against visibly pushdown languages is decidable

Modular Constraint Solver Cooperation via Abstract Interpretation

Cooperation among constraint solvers is difficult because different solving paradigms have different theoretical foundations. Recent works have shown that abstract interpretation can provide a unifying theory for various constraint solvers. In particular, it relies on abstract domains which capture constraint languages as ordered structures. The key insight of this paper is viewing cooperation schemes as abstract domains combinations. We propose a modular framework in which solvers and cooperation schemes can be seamlessly added and combined. This differs from existing approaches such as SMT where the cooperation scheme is usually fixed (e.g., Nelson-Oppen). We contribute to two new cooperation schemes: (i) interval propagators completion that allows abstract domains to exchange bound constraints, and (ii) delayed product which exchanges over-approximations of constraints between two abstract domains. Moreover, the delayed product is based on delayed goal of logic programming, and it shows that abstract domains can also capture control aspects of constraint solving. Finally, to achieve modularity, we propose the shared product to combine abstract domains and cooperation schemes. Our approach has been fully implemented, and we provide various examples on the flexible job shop scheduling problem. Under consideration for acceptance in TPLP.Comment: Paper presented at the 36th International Conference on Logic Programming (ICLP 2020), University Of Calabria, Rende (CS), Italy, September 2020, 17 pages. v2: Fix an example in Section 3.2 (improved closure

A polynomial procedure for trimming visibly pushdown automata

We describe a polynomial procedure which, given a visibly pushdown automaton that accepts only well-nested words, returns an equivalent visibly pushdown automaton that is trimmed. We also show that this procedure can be applied to weighted visibly pushdown automata such as visibly pushdown transducers

Business-to-Consumer Web Site Quality and Web Shoppers\u27 Emotions: Exploring a Research Model

Based on the literature on consumer behavior, psychology, and information systems, this paper explores relationships between Web site quality, the cognitive appraisal of situational state (a key cognitive antecedent to emotions) and a set of positive and negative emotions. A theoretical model is tested on data collected from 215 different Web shopping episodes. Results show that when shopping on business-to-consumer Web sites for low-touch products (music CDs and movies in DVD format), customers felt emotions, namely liking, joy, pride, dislike, frustration, and fear. Even though the mean intensity levels of these emotions is low to moderate, for a substantial number of shoppers (near a third of the sample population) the emotions of liking and joy were felt intensely. Results also indicate that Web site quality, measured by several Web site design components, has a positive impact on the cognitive appraisal of situational state, operationalized as the satisfaction level of the overall online shopping experience. In turn, this appraisal affects all emotions felt by shoppers except fear. This study is particularly addressed to designers and managers of B2C Web sites as it invites them to consider Web shoppers’ emotions while designing and developing their electronic platform

Hierarchies and shape-space for PET image segmentation

International audiencePositron Emission Tomography (PET) image segmentation is essential for detecting lesions and quantifying their metabolic activity. Due to the spatial and spectral properties of PET images, most methods rely on intensity-based strategies. Recent methods also propose to integrate anatomical priors to improve the segmentation process. In this article, we show how the hierarchical approaches proposed in mathematical morphology can efficiently handle these different strategies. Our contribution is twofold. First, we present the component-tree as a relevant data-structure for developing interactive , real-time, intensity-based segmentation of PET images. Second, we prove that thanks to the recent concept of shaping, we can efficiently involve a priori knowledge for lesion segmentation, while preserving the good properties of component-tree segmenta-tion. Preliminary experiments on synthetic and real PET images of lymphoma demonstrate the relevance of our approach

Eutrophisation en milieu lagonaire : compte-rendu subvention CORDET no 94 T 09

La finalité du programme ANTROPIC est de dresser un bilan des conditions du milieu (eutrophisation, hypersédimentation) dans la zone la plus urbanisée du lagon de Tahiti, de proposer des outils de diagnostic de l'état de l'environnement lagonaire utiles pour la gestion du milie