Candidate exoplanet host HD131399A: a nascent Am star

Direct imaging suggests that there is a Jovian exoplanet around the primary A-star in the triple-star system HD131399. We investigate a high-quality spectrum of the primary component HD131399A obtained with FEROS on the ESO/MPG 2.2m telescope, aiming to characterise the star's atmospheric and fundamental parameters, and to determine elemental abundances at high precision and accuracy. The aim is to constrain the chemical composition of the birth cloud of the system and therefore the bulk composition of the putative planet. A hybrid non-local thermal equilibrium (non-LTE) model atmosphere technique is adopted for the quantitative spectral analysis. Comparison with the most recent stellar evolution models yields the fundamental parameters. The atmospheric and fundamental stellar parameters of HD131399A are constrained to Teff=9200+-100 K, log g=4.37+-0.10, M=1.95+0.08-0.06 Msun, R=1.51+0.13-0.10 Rsun, and log L/Lsun=1.17+-0.07, locating the star on the zero-age main sequence. Non-LTE effects on the derived metal abundances are often smaller than 0.1dex, but can reach up to ~0.8dex for individual lines. The observed lighter elements up to calcium are overall consistent with present-day cosmic abundances, with a C/O ratio of 0.45$\pm$0.07 by number, while the heavier elements show mild overabundances. We conclude that the birth cloud of the system had a standard chemical composition, but we witness the onset of the Am phenomenon in the slowly rotating star. We furthermore show that non-LTE analyses have the potential to solve the remaining discrepancies between observed abundances and predictions by diffusion models for Am stars. Moreover, the present case allows mass loss, not turbulent mixing, to be identified as the main transport process competing with diffusion in very young Am stars.Comment: 5 pages + 3 pages appendix, 3 figures. Accepted for publication in A&

Analysis of textile composite structures with finite Volume-p-Elements

Anisotropic textile composites show nonlinear deformation and complex fai- lure behaviour. In particular three-dimensional reinforced textile composites are characterised by an orthotropic material behaviour. To achieve the full po- tential of textile composites the material and especially the failure behaviour has to be analysed particularly for regions dominated by three-dimensional stress distributions, e. g. load introduction areas. For these purposes finite volume-p-elements based on hierarchical shape functions are being developed. Furthermore the constitutive model is en- hanced to simulate material degradation and failure processes. Based on an anisotropic continuum damage model the material degradation is described with tensorial damage variables that characterise the crack density observed in experimental studies of Non-Crimp-Fabrics with E-Glass fibres. The deter- mination of the onset of degradation and the strength prediction is enabled by coupling the damage model with a failure criterion for three-dimensional reinforced plastics. Due to control the spatial adaptivity of polynomial order of the shape functi- ons different a posteriori error estimators are evaluated and compared espe- cially with respect to the applicability on structural models representing or- thotropic material behaviour. Experimental analyses were used to determine the parameters of the consti- tutive model. Besides the in-plane properties the through-thickness material properties are assumed to be primarily important for textile composites. The- refore a modified Arcan testing device was developed which provides test results for biaxial tension and shear load combinations taking the material thickness direction into account. Finally simulations and experimental analyses of a thick double holed plate - the loadintroduction of an elevator bucket - demonstrate the applicability of the material model and finite element implementation

Finiteness theorems in stochastic integer programming

We study Graver test sets for families of linear multi-stage stochastic integer programs with varying number of scenarios. We show that these test sets can be decomposed into finitely many ``building blocks'', independent of the number of scenarios, and we give an effective procedure to compute these building blocks. The paper includes an introduction to Nash-Williams' theory of better-quasi-orderings, which is used to show termination of our algorithm. We also apply this theory to finiteness results for Hilbert functions.Comment: 36 p

3-manifold groups are virtually residually p

Given a prime $p$, a group is called residually $p$ if the intersection of its $p$-power index normal subgroups is trivial. A group is called virtually residually $p$ if it has a finite index subgroup which is residually $p$. It is well-known that finitely generated linear groups over fields of characteristic zero are virtually residually $p$ for all but finitely many $p$. In particular, fundamental groups of hyperbolic 3-manifolds are virtually residually $p$. It is also well-known that fundamental groups of 3-manifolds are residually finite. In this paper we prove a common generalization of these results: every 3-manifold group is virtually residually $p$ for all but finitely many $p$. This gives evidence for the conjecture (Thurston) that fundamental groups of 3-manifolds are linear groups

Automatic Tool-Chain Testing System

Projekt Lissom se zabývá vývojem prostředí pro návrh aplikačně specifických procesorů či SoC (System on Chip). Vyvíjí nástroje typu assembler, disassembler, simulátor, překladač jazyka C apod. Celé prostředí je třeba průběžně testovat, proto také vznikla tato práce. Práce se zabývá softwarovým testováním obecně, jeho rozdělením a popsáním několika existujících systémů. Těmi se inspiruje, řeší návrh a implementaci testovacího systému pro projekt Lissom. Systém je postaven na porovnávání výstupů nástrojů s jejich referenčními protějšky. Pro kompletní funkčnost systému byly navíc naprogramovány nástroje pro komunikaci se systémem Bugzilla a jednoduchý odesilatel e-mailů.Project Lissom is developing environment for design application specific processors or SoC (System on Chip). Project developes tools like assembler, disassembler, simulator, C compiler etc. Environment testing is required and It's main reason for this work. The work is about software testing, types of testing and about existing testing systems. The inspiration from existing systems is used for design and implementation Lissom testing system. System is comparing tools outputs with reference files. The system needs Bugzilla client end e-mail sender for complete functionality. These tools were also created.