The Vampire and the FOOL

This paper presents new features recently implemented in the theorem prover Vampire, namely support for first-order logic with a first class boolean sort (FOOL) and polymorphic arrays. In addition to having a first class boolean sort, FOOL also contains if-then-else and let-in expressions. We argue that presented extensions facilitate reasoning-based program analysis, both by increasing the expressivity of first-order reasoners and by gains in efficiency

Ocorrência do míldio da videira em diferentes épocas de podas em Petrolina - PE.

Suplemento. Edição dos Resumos do 44 Congresso Brasileiro de Fitopatologia, Bento Gonçalves, ago. 2011

On multigraded generalizations of Kirillov-Reshetikhin modules

We study the category of Z^l-graded modules with finite-dimensional graded pieces for certain Z+^l-graded Lie algebras. We also consider certain Serre subcategories with finitely many isomorphism classes of simple objects. We construct projective resolutions for the simple modules in these categories and compute the Ext groups between simple modules. We show that the projective covers of the simple modules in these Serre subcategories can be regarded as multigraded generalizations of Kirillov-Reshetikhin modules and give a recursive formula for computing their graded characters

Microstructure identification via detrended fluctuation analysis of ultrasound signals

We describe an algorithm for simulating ultrasound propagation in random one-dimensional media, mimicking different microstructures by choosing physical properties such as domain sizes and mass densities from probability distributions. By combining a detrended fluctuation analysis (DFA) of the simulated ultrasound signals with tools from the pattern-recognition literature, we build a Gaussian classifier which is able to associate each ultrasound signal with its corresponding microstructure with a very high success rate. Furthermore, we also show that DFA data can be used to train a multilayer perceptron which estimates numerical values of physical properties associated with distinct microstructures.Comment: Submitted to Phys. Rev.

Hierarchic Superposition Revisited

Many applications of automated deduction require reasoning in first-order logic modulo background theories, in particular some form of integer arithmetic. A major unsolved research challenge is to design theorem provers that are "reasonably complete" even in the presence of free function symbols ranging into a background theory sort. The hierarchic superposition calculus of Bachmair, Ganzinger, and Waldmann already supports such symbols, but, as we demonstrate, not optimally. This paper aims to rectify the situation by introducing a novel form of clause abstraction, a core component in the hierarchic superposition calculus for transforming clauses into a form needed for internal operation. We argue for the benefits of the resulting calculus and provide two new completeness results: one for the fragment where all background-sorted terms are ground and another one for a special case of linear (integer or rational) arithmetic as a background theory

Structural properties of crumpled cream layers

The cream layer is a complex heterogeneous material of biological origin which forms spontaneously at the air-milk interface. Here, it is studied the crumpling of a single cream layer packing under its own weight at room temperature in three-dimensional space. The structure obtained in these circumstances has low volume fraction and anomalous fractal dimensions. Direct means and noninvasive NMR imaging technique are used to investigate the internal and external structure of these systems.Comment: 9 pages, 4 figures, accepted in J. Phys. D: Appl. Phy

Approaching the Coverability Problem Continuously

The coverability problem for Petri nets plays a central role in the verification of concurrent shared-memory programs. However, its high EXPSPACE-complete complexity poses a challenge when encountered in real-world instances. In this paper, we develop a new approach to this problem which is primarily based on applying forward coverability in continuous Petri nets as a pruning criterion inside a backward coverability framework. A cornerstone of our approach is the efficient encoding of a recently developed polynomial-time algorithm for reachability in continuous Petri nets into SMT. We demonstrate the effectiveness of our approach on standard benchmarks from the literature, which shows that our approach decides significantly more instances than any existing tool and is in addition often much faster, in particular on large instances.Comment: 18 pages, 4 figure

Scattering map for two black holes

We study the motion of light in the gravitational field of two Schwarzschild black holes, making the approximation that they are far apart, so that the motion of light rays in the neighborhood of one black hole can be considered to be the result of the action of each black hole separately. Using this approximation, the dynamics is reduced to a 2-dimensional map, which we study both numerically and analytically. The map is found to be chaotic, with a fractal basin boundary separating the possible outcomes of the orbits (escape or falling into one of the black holes). In the limit of large separation distances, the basin boundary becomes a self-similar Cantor set, and we find that the box-counting dimension decays slowly with the separation distance, following a logarithmic decay law.Comment: 20 pages, 5 figures, uses REVTE

Ganho genético em potencial produtivo do arroz irrigado no Rio Grande do Sul, após o lançamento da cultivar BR-IRGA 409.

Este trabalho teve como objetivo estimar os ganhos genéticos em rendimento de grãos nos últimos 30 anos, ou a partir do lançamento da cultivar BR-IRGA 409, no estado do Rio Grande do Sul, com base no desempenho de cultivares representativas lançadas pela pesquisa

Análise genética entre acessos de Oenocarpus mapora (Arecaceae) de hábito cespitoso e solitário.

A bacaby ou Oenocarpus mapora é uma palmeira considerada potencial para a domesticação devido às suas características comerciais de seu fruto e palmito. A espécie tem hábito predominantemente cespitoso, mas palmeiras de hábito solitário já foram descritas. O banco de germoplasma (BAG) do complexo Oenocarpus/Jessenia da Embrapa Amazônia Oriental possui em seu acervo uma amostra de materiais do tipo solitário de O. mapora coletados no noroeste paraense. Para veriicar a diversidade genética desse grupo no BAG e sua proximidade genética com materiais de hábito cespitoso, foram utilizados 18 indivíduos do tipo solitário para serem comparados com 1γ indivíduos do tipo cespitoso coletados em Itacoatiara (Aε) e oito coletados em Parintins (Aε), por meio de genotipagem com cinco locos microssatélites. A análise descritiva mostrou que há variabilidade genética dentro do grupo do tipo solitário, com H E = 0,7λ, variação que foi maior que a dos grupos de hábito cespitoso. A análise com AεOVA demonstrou grande diferenciação entre os grupos, com γβ,γη% de variação genética entre grupos. A distância genética par a par com base em FST mostrou que houve diferença significativa entre os grupos, e que o grupo do tipo solitário teve mais proximidade genética com um dos grupos do tipo cespitoso, do que entre os grupos do tipo cespitoso, indicando que o material pode ser utilizado em programas de melhoramento