JH-singularity and JH-regularity of multivariate stationary processes over LCA groups

Let G be an LCA group, I' its dual group, and H a closed subgroup of G such that its annihilator is countable. Let M denote a regular positive semidefinite matrix-valued Borel measure on I' and L^2(M) the corresponding Hilbert space of matrix-valued functions square-integrable with respect to M. For g ϵ G, let Z_g be the closure in L^2(M) of all matrix-valued trigonometric polynomials with frequencies from g+H. We describe those measures M for which Z_g = L^2(M) as well as those for which ∩ gϵG Zg = {0}. Interpreting M as a spectral measure of a multivariate wide sense stationary processon G and denoting by J_H the family of H-cosets we obtain conditions forJ_H-singularity and JH-regularity.Fil: Klotz, Lutz Peter. Universitat Leipzig; AlemaniaFil: Medina, Juan Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática Alberto Calderón; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Matemáticas; Argentin

Dynamic Feedback Linearization of Control Systems with Symmetry

Control systems of interest are often invariant under Lie groups of transformations. Given such a control system, assumed to not be static feedback linearizable, a verifiable geometric condition is described and proven to guarantee its dynamic feedback linearizability. Additionally, a systematic procedure for obtaining all the system trajectories is shown to follow from this condition. Besides smoothness and the existence of symmetry, no further assumption is made on the local form of a control system, which is therefore permitted to be fully nonlinear and time varying. Likewise, no constraints are imposed on the local form of the dynamic compensator. Particular attention is given to those systems requiring non-trivial dynamic extensions; that is, beyond augmentation by chains of integrators. Nevertheless, the results are illustrated by an example of each type. Firstly, a control system that can be dynamically linearized by a chain of integrators, and secondly, one which does not possess any linearizing chains of integrators and for which a dynamic feedback linearization is nevertheless derived. These systems are discussed in some detail. The constructions have been automated in the Maple package DifferentialGeometry.Comment: 41 pages, minor revisions and error correction

Thermodynamic Assessment of the Sn-Ti System

Summary.: The knowledge of phase equilibria and thermodynamic properties in the ternary Cu-Sn-Ti system is of technical importance for active brazing filler metals. Thermodynamic descriptions of the binary systems Cu-Ti and Cu-Sn are well established. In this work a self-consistent thermodynamic description of the Sn-Ti binary system has been obtained by fitting critically reviewed thermochemical and phase diagram data. The newest and most consistent lattice stability has been used, and all the intermetallic phases and recent experimental information have been taken into account. The equilibrium measurement on the Sn-rich side and more experimental thermodynamic properties are required for a better thermodynamic description of this system. The evaluated thermodynamic description of the Sn-Ti binary system will serve as part of the thermodynamic database for Cu-Sn-Ti brazing alloy

Simplified SPARQL REST API - CRUD on JSON Object Graphs via URI Paths

Within the Semantic Web community, SPARQL is one of the predominant languages to query and update RDF knowledge. However, the complexity of SPARQL, the underlying graph structure and various encodings are common sources of confusion for Semantic Web novices. In this paper we present a general purpose approach to convert any given SPARQL endpoint into a simple to use REST API. To lower the initial hurdle, we represent the underlying graph as an interlinked view of nested JSON objects that can be traversed by the API path.Comment: 5 pages, 2 figures, ESWC 2018 demo pape

Genome sequence of OXA-23 producing Acinetobacter baumannii IHIT7853, a carbapenem-resistant strain from a cat belonging to international clone IC1

Background: Multidrug resistance in Acinetobacter baumannii has dramatically increased in recent years worldwide. Thus, last-line antibiotics like carbapenems are increasingly being used which in turn further augments selection pressure for resistant strains. Resistance to carbapenems in A. baumannii is frequently mediated by carbapenemases, particularly OXA-23 and OXA-58. Carbapenemase-producing bacteria are mainly described in human patients and the intestinal tract represents a common source for such pathogens. In this study, we sequenced and analyzed the genome of A. baumannii IHIT7853, a carbapenem-resistant, OXA-23 producing strain isolated from cystitis in a cat in 2000 in Germany. Results: Phylogenetic analysis revealed that IHIT7853 belonged to the globally distributed international clone IC1 and MLST type ST1/ST231 (Pasteur/Oxford MLST scheme). A phylogenetic tree based on the maximum common genome of 18 A. baumannii isolates placed IHIT7853 close to human clinical isolates, such as the multidrug-resistant (MDR) outbreak strain AYE that was isolated from a patient with pneumonia and cystitis in 2001 in France. The OXA-23 plasmid sequence could be determined as 53,995 bp in size, possessing resistance genes strA and strB in addition to bla OXA-23. Conclusions: The analysis of the genome of IHIT7853 reveals that companion animals carry MDR A. baumannii that resemble relevant clonal lineages involved in severe infections in humans. As urinary tract infections are often caused by bacteria that reside in the intestinal tract, future studies should unveil, if the animal gut serves as a source for MDR A. baumannii