A geometric approach to dense Cayley digraphs of finite Abelian groups

We give a method for constructing infinite families of dense (or eventually likely dense) Cayley digraphs of finite Abelian groups. The diameter of the digraphs is obtained by means of the related minimum distance diagrams. A dilating technique for these diagrams, which can be used for any degree of the digraph, is applied to generate the digraphs of the family. Moreover, two infinite families of digraphs with distinguished metric properties will be given using these methods. The first family contains digraphs with asymptotically large ratio between the order and the diameter as the degree increases (moreover it is the first known asymptotically dense family). The second family, for fixed degree d = 3, contains digraphs with the current best known density.Peer ReviewedPostprint (author's final draft

Abelian Cayley digraphs with asymptotically large order for any given degree

Abelian Cayley digraphs can be constructed by using a generalization to Z(n) of the concept of congruence in Z. Here we use this approach to present a family of such digraphs, which, for every fixed value of the degree, have asymptotically large number of vertices as the diameter increases. Up to now, the best known large dense results were all non-constructive.Peer ReviewedPostprint (author's final draft

Azide-alkyne cycloadditions in a vortex fluidic device: Enhanced "on water" effects and catalysis in flow

The Vortex Fluidic Device is a flow reactor that processes reactions in thin films. Running the metal-free azide-alkyne cycloaddition in this reactor revealed a dramatic enhancement of the "on water"effect. For the copper-catalyzed azide-alkyne cycloaddition, stainless steel or copper jet feeds were effective reservoirs of active copper catalyst.Fil: Oksdath Mansilla, Gabriela. Flinders University.; Australia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Kucera, Renata L.. Flinders University.; AustraliaFil: Chalker, Justin Mark. Flinders University.; AustraliaFil: Raston, Colin Llewellyn. Flinders University.; Australi

High temperature push-out tests on demountable shear connectors of steel-concrete composite beams

[EN] There is no denying that there is a growing need for reusable systems in the construction industry. This is not only a by-product of the increasing demand of materials, but also a necessity to reduce greenhouse gas emissions associated to the manufacturing process of construction components. Reusable systems aim to solidify the transition from a linear economy model to a circular economy model, where the lifecycle of materials is extended overtime. However, there are several factors that might hinder the reusability of structural components, ranging from regular use over a time period to accidental situations, such as earthquakes and fires. This experimental study focuses its efforts on the analysis of demountable shear connectors for composite structural systems under the influence of high temperatures that resemble a situation of fire. The main idea behind this experimental campaign is to combine a standard push-out test, where a specimen composed by a HEB-260 steel profile with reinforced concrete slabs connected to its flanges via high strength bolts is subjected to a vertical force by utilizing a hydraulic jack with a simultaneous thermal action. The tests reproduce a previous experimental campaign performed at the University of Luxembourg (cylinder and coupler systems), but subjected to 4 different temperatures (20, 300, 500 and 600 °C). The loss of strength of the connectors with the temperature, the failure mode and the reusability after a situation of fire are discussed in the present study.Mansilla, R.; Espinós Capilla, A.; Paya-Zaforteza, I.; Odenbreit, C.; Romero, ML. (2023). High temperature push-out tests on demountable shear connectors of steel-concrete composite beams. Ernst & Sohn, Wiley Online Library. 2074-2079. https://doi.org/10.1002/cepa.23602074207

Low Side Gan Fet Driver for Space Applications

This paper reports the results of preliminary single event effects (SEE) testing of the Intersil ISL70040SEH, a single low side driver specifically designed to drive enhancement mode power GaN FETs

Spectral Analysis of Guanine and Cytosine Fluctuations of Mouse Genomic DNA

We study global fluctuations of the guanine and cytosine base content (GC%) in mouse genomic DNA using spectral analyses. Power spectra S(f) of GC% fluctuations in all nineteen autosomal and two sex chromosomes are observed to have the universal functional form S(f) \sim 1/f^alpha (alpha \approx 1) over several orders of magnitude in the frequency range 10^-7< f < 10^-5 cycle/base, corresponding to long-ranging GC% correlations at distances between 100 kb and 10 Mb. S(f) for higher frequencies (f > 10^-5 cycle/base) shows a flattened power-law function with alpha < 1 across all twenty-one chromosomes. The substitution of about 38% interspersed repeats does not affect the functional form of S(f), indicating that these are not predominantly responsible for the long-ranged multi-scale GC% fluctuations in mammalian genomes. Several biological implications of the large-scale GC% fluctuation are discussed, including neutral evolutionary history by DNA duplication, chromosomal bands, spatial distribution of transcription units (genes), replication timing, and recombination hot spots.Comment: 15 pages (figures included), 2 figure

Flujo de diseño asíncrono con la biblioteca DCVSL_LIB para ES2 ECPD10

En el presente trabajo se pretende abordar la metodología a seguir durante el flujo de diseño de un circuito asíncrono orientado a prestaciones, utilizando la biblioteca DCVSL_LIB para aplicaciones asíncronas que hemos desarrollado. Este proceso se aplicará desde un nivel semicustom. La concepción de los algoritmos del sistema se desarrollaran desde una metodología top-down, dadas las restricciones que por construcción debe contener un control asíncrono. Mientras que aspectos tales como el procesado del flujo de datos y control sobre el datapath se aplicaran con una jerarquía botton-up, facilitando la concepción de circuitos asíncronos sencillos y de elevadas prestaciones a partir de soluciones arquitecturales conocidas.Postprint (published version

Protective films on complex substrates of thermoplastic and cellular elastomers:Prospective applications to rubber, nylon and cork

Deposition of thin films is an appropriate methodology to enhance the performance of a material by modification of its surface, while keeping the properties of the bulk largely unaffected. However, a practical implementation becomes less straightforward when dealing with sensitive or complex substrates, for instance, those which cannot be subjected to harsh treatments, such as cleaning and etching, or extreme deposition conditions, like high temperatures, and ion impingement et cetera. This paper concentrates on deposition processing of complex substrates. In particular, it discusses the deposition of two types of protective coatings (diamond-like carbon (DLC) films against friction and wear, and TiO2 films against UV light) on three types of thermoplastic and cellular elastomers (rubber, nylon and cork). It is demonstrated that a successful protection of thermoplastic elastomers against wear with DLC films can be attained, after a thorough adaptation of the procedure to the characteristics of the specific substrate. In addition, the paper reports the very first depositions on a cellular elastomer like cork by vapor deposition methods, including Atomic Layer Deposition (ALD)