Synthesis of OCL Pre-conditions for Graph Transformation Rules

Proceedings of: Third International Conference on Model Transformation (ICMT 2010): Theory and Practice of Model Transformation. Málaga, Spain, 28 June-02 July, 2010Graph transformation (GT) is being increasingly used in Model Driven Engineering (MDE) to describe in-place transformations like animations and refactorings. For its practical use, rules are often complemented with OCL application conditions. The advancement of rule post-conditions into pre-conditions is a well-known problem in GT, but current techniques do not consider OCL. In this paper we provide an approach to advance post-conditions with arbitrary OCL expressions into pre-conditions. This presents benefits for the practical use of GT in MDE, as it allows: (i) to automatically derive pre-conditions from the meta-model integrity constraints, ensuring rule correctness, (ii) to derive pre-conditions from graph constraints with OCL expressions and (iii) to check applicability of rule sequences with OCL conditions.Work funded by the Spanish Ministry of Science and Innovation through projects “Design and construction of a Conceptual Modeling Assistant” (TIN2008-00444/TIN - Grupo Consolidado), “METEORIC” (TIN2008-02081),mobility grants JC2009-00015 and PR2009-0019, and the R&D program of the Community of Madrid (S2009/TIC-1650, project “e-Madrid”).Publicad

Система обработки данных по оптическим и микрофизическим характеристикам аэродисперсной среды для оценки ослабления лучистой энергии

Разработана информационно-вычислительная система, реализующая численный эксперимент по определению ослабления и пропускания оптического излучения аэродисперсной средой. В качестве моделей отдельных рассеивателей рассмотрены столбики, пластинки, сферы, а также их агрегатов. В систему включаются архивы баз данных Aeronet и Hitran оптических и микрофизических характеристик кристаллических облаков. Программный комплекс ориентирован на обработку данных по ослаблению видимого и ИК излучения. Сравнительный анализ данных численного и натурного экспериментов показал возможность оценки физико-химических параметров среды

Graph-Based Shape Analysis Beyond Context-Freeness

We develop a shape analysis for reasoning about relational properties of data structures. Both the concrete and the abstract domain are represented by hypergraphs. The analysis is parameterized by user-supplied indexed graph grammars to guide concretization and abstraction. This novel extension of context-free graph grammars is powerful enough to model complex data structures such as balanced binary trees with parent pointers, while preserving most desirable properties of context-free graph grammars. One strength of our analysis is that no artifacts apart from grammars are required from the user; it thus offers a high degree of automation. We implemented our analysis and successfully applied it to various programs manipulating AVL trees, (doubly-linked) lists, and combinations of both

Soft Covariant Gauges on the Lattice

We present an exploratory study of a one-parameter family of covariant, non-perturbative lattice gauge-fixing conditions, that can be implemented through a simple Monte Carlo algorithm. We demonstrate that at the numerical level the procedure is feasible, and as a first application we examine the gauge dependence of the gluon propagator.Comment: 11 pages, Latex, epsf.sty included + 5 PostScript picture

Evolution along the Great Rift Valley: phenotypic and genetic differentiation of East African white-eyes (Aves, Zosteropidae)

The moist and cool cloud forests of East Africa represent a network of isolated habitats that are separated by dry and warm lowland savannah, offering an opportunity to investigate how strikingly different selective regimes affect species diversification. Here, we used the passerine genus Zosterops (white-eyes) from this region as our model system. Species of the genus occur in contrasting distribution settings, with geographical mountain isolation driving diversification, and savannah interconnectivity preventing differentiation. We analyze (1) patterns of phenotypic and genetic differentiation in high- and lowland species (different distribution settings), (2) investigate the potential effects of natural selection and temporal and spatial isolation (evolutionary drivers), and (3) critically review the taxonomy of this species complex. We found strong phenotypic and genetic differentiation among and within the three focal species, both in the highland species complex and in the lowland taxa. Altitude was a stronger predictor of phenotypic patterns than the current taxonomic classification. We found longitudinal and latitudinal phenotypic gradients for all three species. Furthermore, wing length and body weight were significantly correlated with altitude and habitat type in the highland species Z.poliogaster. Genetic and phenotypic divergence showed contrasting inter- and intraspecific structures. We suggest that the evolution of phenotypic characters is mainly driven by natural selection due to differences in the two macro-habitats, cloud forest and savannah. In contrast, patterns of neutral genetic variation appear to be rather driven by geographical isolation of the respective mountain massifs. Populations of the Z.poliogaster complex, as well as Z.senegalensis and Z.abyssinicus, are not monophyletic based on microsatellite data and have higher levels of intraspecific differentiation compared to the currently accepted species

A multidisciplinary engineering summer school in an industrial setting

Most university-level engineering studies produce technically skilled engineers. However, typically students face several difficulties whenworking in multidisciplinary teams when they initiate their industrial careers. In a globalised world, it becomes increasingly important that engineers are capable of collaborating across disciplinary boundaries and exhibit soft competencies, like communication, interpersonal and social skills, time planning, creativity, initiative, and reflection. To prepare a group of engineering and industrial design students to acquire those capabilities, an international summer school that combined industrial design with different kinds of engineering disciplineswas organised on the site of Bang&Olufsen (B&O) in Denmark. This multidisciplinary engineering summer school was attended by students from six European university-level teaching institutions and was supervised by teachers from those institutions and industrial experts from B&O. The main aim of the summer school was to allow students to work in teams, composed of students from different knowledge disciplines and with different cultural backgrounds, with the purpose of developing innovative concepts and products, within a strong industrial perspective.B&OERASMU

Benchmark Framework for Virtual Students’ Behaviours

This paper demonstrates the integration and evaluation of different atmosphere models into Virtual Reality (VR) training for teacher education. We developed three behaviour models to simulate different levels of class discipline. We evaluated their performances using a combination of objective and subjective measurements. Our initial results suggest that the more believable and distinguishable classroom atmospheres are produced by creating more consistent behaviours across virtual students. Our results confirm the importance of similar behaviours to elicit a particular atmosphere

Confinement Phenomenology in the Bethe-Salpeter Equation

We consider the solution of the Bethe-Salpeter equation in Euclidean metric for a qbar-q vector meson in the circumstance where the dressed quark propagators have time-like complex conjugate mass poles. This approximates features encountered in recent QCD modeling via the Dyson-Schwinger equations; the absence of real mass poles simulates quark confinement. The analytic continuation in the total momentum necessary to reach the mass shell for a meson sufficiently heavier than 1 GeV leads to the quark poles being within the integration domain for two variables in the standard approach. Through Feynman integral techniques, we show how the analytic continuation can be implemented in a way suitable for a practical numerical solution. We show that the would-be qbar-q width to the meson generated from one quark pole is exactly cancelled by the effect of the conjugate partner pole; the meson mass remains real and there is no spurious qbar-q production threshold. The ladder kernel we employ is consistent with one-loop perturbative QCD and has a two-parameter infrared structure found to be successful in recent studies of the light SU(3) meson sector.Comment: Submitted for publication; 10.5x2-column pages, REVTEX 4, 3 postscript files making 3 fig