Estudio del telégrafo de Agustín de Betancourt

The transmission of information has gone through various stages of evolution throughout its history. A stage before that of the electric telegraph was the so-called aerial/optical telegraph. It was developed towards the end of the 18th century and was in service until the middle of the 19th century. The system developed by Claude Chappe in France was the first to be in consistent use. However, a new and technologically superior system was proposed soon. Its inventor was Agustín de Betancourt, who, together with the distinguished clockmaker Breguet, presented it to the French Authorities in the turbulent decade of the 1790s. This doctoral thesis presents a historical review of this telegraph and analyzes its technical characteristics. It presents analytically, numerically and graphically some of the statements made about the telegraph, and corrects other subsequent observations. Lastly, a detailed reconstruction of the telegraph is made using different advanced CAD techniques, which provide an accurate static and dynamic view of each of its parts

Impact properties and water uptake behavior of old newspaper recycled fibers-reinforced polypropylene composites

Natural fiber-reinforced thermoplastic composites can be an alternative to mineral fiber-based composites, especially when economic and environment concerns are included under the material selection criteria. In recent years, the literature has shown how lignocellulosic fiber-reinforced composites can be used for a variety of applications. Nonetheless, the impact strength and the water uptake behavior of such materials have been seen as drawbacks. In this work, the impact strength and the water uptake of composites made of polypropylene reinforced with fibers from recycled newspaper have been researched. The results show how the impact strength decreases with the percentage of reinforcement in a similar manner to that of glass fiber-reinforced polypropylene composites as a result of adding a fragile phase to the material. It was found that the water uptake increased with the increasing percentages of lignocellulosic fibers due to the hydrophilic nature of such reinforcements. The diffusion behavior was found to be Fickian. A maleic anhydride was added as a coupling agent in order to increase the strength of the interface between the matrix and the reinforcements. It was found that the presence of such a coupling agent increased the impact strength of the composites and decreased the water uptake. Impact strengths of 21.3 kJ/m3 were obtained for a coupled composite with 30 wt % reinforcement contents, which is a value higher than that obtained for glass fiber-based materials. The obtained composites reinforced with recycled fibers showed competitive impact strength and water uptake behaviors in comparison with materials reinforced with raw lignocellulosic fibers. The article increases the knowledge on newspaper fiber-reinforced polyolefin composite properties, showing the competitiveness of waste-based materialsPostprint (published version

Topography of the interfacial shear strength and the mean intrinsic tensile strength of hemp fibers as a reinforcement of polypropylene

The strength of the interphase between the reinforcements and the matrix has a major role in the mechanical properties of natural ¿ber reinforced polyole¿n composites. The creation of strong interphases is hindered by the hydrophobic and hydrophilic natures of the matrix and the reinforcements, respectively. Adding coupling agents has been a common strategy to solve this problem. Nonetheless, a correct dosage of such coupling agents is important to, on the one hand guarantee strong interphases and high tensile strengths, and on the other hand ensure a full exploitation of the strengthening capabilities of the reinforcements. The paper proposes using topographic pro¿le techniques to represent the e¿ect of reinforcement and coupling agent contents of the strength of the interphase and the exploitation of the reinforcements. This representation allowed identifying the areas that are more or less sensitive to coupling agent content. The research also helped by ¿nding that an excess of coupling agent had less impact than a lack of this componentPostprint (published version

Computer-aided sketching: incorporating the locus to improve the three-dimensional geometric design

This article presents evidence of the convenience of implementing the geometric places of the plane into commercial computer-aided design (CAD) software as auxiliary tools in the computer-aided sketching process. Additionally, the research considers the possibility of adding several intuitive spatial geometric places to improve the efficiency of the three-dimensional geometric design. For demonstrative purposes, four examples are presented. A two-dimensional figure positioned on the flat face of an object shows the significant improvement over tools currently available in commercial CAD software, both vector and parametric: it is more intuitive and does not require the designer to execute as many operations. Two more complex three-dimensional examples are presented to show how the use of spatial geometric places, implemented as CAD software functions, would be an effective and highly intuitive tool. Using these functions produces auxiliary curved surfaces with points whose notable features are a significant innovation. A final example provided solves a geometric place problem using own software designed for this purpose. The proposal to incorporate geometric places into CAD software would lead to a significant improvement in the field of computational geometry. Consequently, the incorporation of geometric places into CAD software could increase technical-design productivity by eliminating some intermediate operations, such as symmetry, among others, and improving the geometry training of less skilled usersPostprint (published version

Investigación en docencia: trabajos en desarrollo

A pesar de que la investigación en docencia ha venido siendo despreciada sistemáticamente en la evaluación de los trabajos del profesorado implicado en esas labores, parece que por fin se ha dejado una puerta abierta para revertir la situación. Dentro de ese contexto, un grupo de profesores relacionados con la docencia y la investigación en el ámbito del diseño (los que suscriben este documento) viene trabajando en varios temas, que están a caballo del desarrollo de las herramientas de CAD y la mejora de la eficiencia en el desarrollo de la docencia. Creemos que este es un buen foro para dar a conocer esos temas de trabajo que en el futuro próximo pueden significar mejoras sustanciales en los dos campos, contribuyendo así a la mejora de las herramientas y a su acercamiento al “modus operandi” de los diseñadores. Esta comunicación pretende por tanto dar a conocer las vertientes sobre las que se aplica esta filosofía de trabajo y los logros actuales alcanzados

Educational software to learn the essentials of engineering graphics

This paper presents a novel educational software package which develops an Interactive Didactic Application (IDA) generated in the Polytechnic University of Catalonia (UPC), and which contains the essentials of Engineering Graphics according to ISO norms. It is an interactive multimedia application which adapts easily to all engineering studies, according to the needs of each course, and which is the nucleus of Computer Assisted Teaching (CAT).Peer ReviewedPostprint (author’s final draft

Diseño gráfico mediante tratamiento de listas numéricas y su aplicación al diseño textil

De todos es conocida la fuerte relación existente entre el diseño, la geometría y las matemáticas, pero hay disciplinas en las que esta realidad se hace mucho más evidente. Una de estas disciplinas es la de Diseño Textil. Este grupo de trabajo ha creado una aplicación interactiva en la que la base de datos sobre la que subyace el diseño son listas de datos, y diseñar consiste en manipular mediante un juego de índices los elementos de las listas. Estos elementos no son más que cifras numéricas, compuestos en base a colores indexados en formato estándar. En el desarrollo del proyecto resulta también imprescindible el color como elemento fundamental para las presentaciones de los diseños, tanto a nivel de pantalla como de impresora. Esta ponencia pretende evidenciar que, con conocimientos informáticos, una buena base matemática y un sistema racional de tratamiento de los índices de las listas numéricas, se puede generar una aplicación que permita transmitir el conocimiento en diferentes ámbitos sustentados en imágenes con aplicación en el diseño textil, ingeniería gráfica, transformaciones matemáticas, lógica de indexación…Postprint (author’s final draft

Recerca i tecnologia en enginyeria gràfica i disseny a la Universitat Politècnica de Catalunya

Els temps canvien cada vegada més ràpidament, i a la universitat això encara es nota més. L’històric departament d‘Expressió Gràfica a l’Enginyeria (EGE) de la Universitat Politècnica de Catalunya, garant d’una docència de Grau, Màster i Doctorat de qualitat i adaptada a les necessitats de la societat, emprèn l’any 2020 amb una proposta de canvi de nom per adaptar-se al nous coneixements que estan esdevenint la seva matèria principal, al voltant de l’enginyeria gràfica i el disseny. Les àrees de recerca del centenar de professors que formen el departament són àmplies i variades, i sempre en col·laboració en diversos grups tant de la pròpia UPC com d’altres universitats. Una recerca avançada, de caràcter pluridisciplinari, on s'apliquen creativitat i innovació com a eines de coneixement, implicats en un territori ampli, i situats als diferents campus de la UPC. En els capítols d’aquest llibre podeu veure una petita mostra d’aquesta recerca tecnològica en camps ben variats.Postprint (published version

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Investigación en docencia: trabajos en desarrollo

A pesar de que la investigación en docencia ha venido siendo despreciada sistemáticamente en la evaluación de los trabajos del profesorado implicado en esas labores, parece que por fin se ha dejado una puerta abierta para revertir la situación. Dentro de ese contexto, un grupo de profesores relacionados con la docencia y la investigación en el ámbito del diseño (los que suscriben este documento) viene trabajando en varios temas, que están a caballo del desarrollo de las herramientas de CAD y la mejora de la eficiencia en el desarrollo de la docencia. Creemos que este es un buen foro para dar a conocer esos temas de trabajo que en el futuro próximo pueden significar mejoras sustanciales en los dos campos, contribuyendo así a la mejora de las herramientas y a su acercamiento al “modus operandi” de los diseñadores. Esta comunicación pretende por tanto dar a conocer las vertientes sobre las que se aplica esta filosofía de trabajo y los logros actuales alcanzados