Nonlinear Optimization of a New Polynomial Tyre Model.

Tyre behavior is strongly nonlinear. This article presents the validation of a new polynomial tyre model with real test data, analyzing the convergence properties during the optimization process to calculate the values of the parameters. A multivariate model with 13 parameters is shown, including normal load and camber angle. The article reviews the methods of getting polynomial approximations of the magic formula tyre model used to develop the new polynomial model, the numerical optimization methods who calculate the parameters of the model from real test data and it explains how the terms of the Jacobian matrix are modified when we impose constraints to the curve; this can be useful to improve the adjustment in some areas of the curve. The convergence properties are shown both for the magic formula tyre model and for this polynomial tyre model. The proposed model presents a fast convergence both in one and in 3 variables. This is an additional advantage to its excellent analytical properties, the model is very easy to compute and can be easily derived and integrated. It is very well adapted for real time computing.pre-print534 K

Open high-level data formats and software for gamma-ray astronomy

In gamma-ray astronomy, a variety of data formats and proprietary software have been traditionally used, often developed for one specific mission or experiment. Especially for ground-based imaging atmospheric Cherenkov telescopes (IACTs), data and software are mostly private to the collaborations operating the telescopes. However, there is a general movement in science towards the use of open data and software. In addition, the next-generation IACT instrument, the Cherenkov Telescope Array (CTA), will be operated as an open observatory. We have created a Github organisation at https://github.com/open- gamma-ray- astro where we are developing high-level data format specifications. A public mailing list was set up at https://lists.nasa.gov/mailman/listinfo/open-gamma- ray-astro and a first face-to-face meeting on the IACT high-level data model and formats took place in April 2016 in Meudon (France). This open multi-mission effort will help to accelerate the development of open data formats and open-source software for gamma-ray astronomy, leading to synergies in the development of analysis codes and eventually better scientific results (reproducible, multi-mission). This write-up presents this effort for the first time, explaining the motivation and context, the available resources and process we use, as well as the status and planned next steps for the data format specifications. We hope that it will stimulate feedback and future contributions from the gamma-ray astronomy community

Dossier. Estudios de códices mesoamericanos en Europa

Sin resume

Elementos y teoría de la arquitectura funcional : Argentina integrada en la síntesis panorámica de la arquitectura moderna

Gli elementi dell'architettura funzionale, publicado por Alberto Sartoris en 1932 es un texto singular en la difusión internacional de la arquitectura moderna que involucra de un modo particular a nuestro país. En 1935 el crítico ítalo-suizo visita Buenos Aires, dicta conferencias y sus ideas se publican de modo sostenido en la prensa arquitectónica y cultural. En la segunda edición del libro, de ese mismo año, incluye en la sección gráfica obras de Argentina, integrándola en el mapa de la modernidad. Este trabajo intenta focalizar una mirada crítica sobre este episodio, reconociendo un campo complejo, con interesantes articulaciones entre la visión global de Sartoris y su mirada externa; en relación a las particularidades de la producción y el debate local en la arquitectura. Poner en perspectiva estos sucesos en el momento de formación de la modernidad hegemónica en la arquitectura argentina, y en el contexto de procesos de metropolización que afectan a la sociedad en su conjunto.Eje: Teoría e Historia de la ArquitecturaFacultad de Arquitectura y Urbanism

Elementos y teoría de la arquitectura funcional : Argentina integrada en la síntesis panorámica de la arquitectura moderna

Gli elementi dell'architettura funzionale, publicado por Alberto Sartoris en 1932 es un texto singular en la difusión internacional de la arquitectura moderna que involucra de un modo particular a nuestro país. En 1935 el crítico ítalo-suizo visita Buenos Aires, dicta conferencias y sus ideas se publican de modo sostenido en la prensa arquitectónica y cultural. En la segunda edición del libro, de ese mismo año, incluye en la sección gráfica obras de Argentina, integrándola en el mapa de la modernidad. Este trabajo intenta focalizar una mirada crítica sobre este episodio, reconociendo un campo complejo, con interesantes articulaciones entre la visión global de Sartoris y su mirada externa; en relación a las particularidades de la producción y el debate local en la arquitectura. Poner en perspectiva estos sucesos en el momento de formación de la modernidad hegemónica en la arquitectura argentina, y en el contexto de procesos de metropolización que afectan a la sociedad en su conjunto.Eje: Teoría e Historia de la ArquitecturaFacultad de Arquitectura y Urbanism

Fast Computing on Vehicle Dynamics Using Chebyshev Series Expansions.

This article focusses on faster computation techniques to integrate mechanical models in electronic advanced active safety applications. It shows the different techniques of approximation in series of functions and differential equations applied to vehicle dynamics. This allows the achievement of approximate polynomial and rational solutions with a very fast and efficient computation. Firstly, the whole theoretical basic principles related to the techniques used are presented: orthogonality of functions, function expansion in Chebyshev and Jacobi series, approximation through rational functions, the Minimax-Remez algorithm, orthogonal rational functions (ORF’s) and the perturbation of dynamic systems theory, that reduces the degree of the expansion polynomials used. As an application, it is shown the obtaining of approximate solutions to the longitudinal dynamics, vertical dynamics, steering geometry and a tyre model, all obtained through development in series of orthogonal functions with a computation much faster than those of its equivalents in the classic vehicle theory. These polynomial partially symbolic solutions present very low errors and very favourable analytical properties due to their simplicity, becoming ideal for real time computation as those required for the simulation of evasive manoeuvres prior a crash. This set of techniques had never been applied to vehicle dynamics before.pre-print748 K

Doctor Agustín O´Horán y Escudero

Escribir una Semblanza del Doctor Agustín Jorge O’Horán y Escudero constituye, para mí, más que una satisfacción, un verdadero privilegio y una encomienda muy grata; aunque nunca conseguirán estas palabras dimensionar y destacar en justa medida, la obra realizada por este ilustre médico