APRÈN. Portal de la producció docent del professorat de la UPC

Throughout this Thesis, the current automotive sector and its limitations have been studied with the aim of presenting a proposal to minimise the environmental impact of this industry. This project is based on the implementation of the use of recycled plastic for the manufacture of 4.2% of the total mass of the car. This document begins by analysing the current situation and economic model. An analysis of the linear economic model has been carried out to conclude the need to change the model and mentality in order to reduce the exploitation of natural resources. The circular economy is presented as a sustainable and effective alternative to 'the imminent need for change'. It then focuses specifically on the automotive sector. This sector, recognized and widespread throughout the world, is one of the most responsible for the climate crisis. This sector is introduced, and its main weaknesses with respect to the environment are exposed. Finally, the implementation of circular models in this industry is shown and different examples of automotive companies that carry out these strategies are shared. Finally, a circular proposal is presented for the Volkswagen Group. The opportunity to work in this company during the last months has driven me to the decision to undertake this project. The German company is one of the most recognized automotive brands worldwide, selling its products to more than 153 countries. In addition, this company promotes the sustainable transition of this sector through the decarbonization of its vehicles in the new launches. However, a sustainable and innovative project is proposed for this company. The project is based on the implementation of recycled polypropylene for the manufacture of parts and parts of the interior of the car. Polypropylene is a material currently used for the manufacture of cars, however the use of this in recycled state is not at all frequent. The project focuses on the specific use of plastic due to the increasing amount of plastic used in new vehicle models, generating more and more negative impact on the environment. Therefore, first of all, the possible types of plastics used in the sector are firstly studied and the feasibility of recycling them is then checked according to whether their properties are maintained once recycled. It is concluded that recycled polypropylene is the most suitable plastic for the requirements of this project. Once the decision has been made to use recycled polypropylene, it is essential to check the profitability of this project by means of a feasibility plan. Based on data provided by the Volkswagen Group, the possible costs, the sales forecast of the new model and the income generated by this project have been estimated. Finally, a hypothetical calculation of the maximum investment that can be supported in order to recover the initial investment within five years is estimated. The Bachelor's Degree is based on the study of Economic Analysis and Industrial Engineering. The knowledge acquired during this degree on how markets work and the different economic methods have been transferred to this Thesis in order to understand how the automobile market works and to be able to apply a feasibility plan. On the other hand, industrial engineering subjects such as environmental management, strength of materials or data management have enhanced the understanding of the topics covered throughout the Thesis and the knowledge learned throughout these years can be reflected in the work

My work focuses on the Elliptic Restricted Three body problem and the coordinate systems used within this restrictive problem. It focuses on the pulsating coordinates and the sidereal coordinates and comes to the conclusion that pulsating coordinates are more appropriate for the Poincare case and when the infinitesimal third particle is close to the libration points. Comparatively, sidereal coordinates are more appropriate for the lunar case and comet case, where the system can be considered a perturbed Kepler Problem.

L'objectiu d'aquest treball és demostrar una inestabilitat que presenta l'equació de Schrödinger no lineal, convenientment reduïda a un sistema finit d'EDO's, mitjançant tècniques pròpies dels Sistemes Dinàmics, com seria l'ús de les anomenades coordenades de Shilnikov.. Es tracta d'utilitzar tècniques avanzades de sistemes dinàmics, concretamet el mètode de Shilnikov, per tal de trobar, de manera constructiva, solucions de l'equació de Schrodinger nolineal cubic defocusing amb transferència considerable d'energia i, en particular, aplicar-ho al model de l'article: J. Colliander, M. Keel, G. Staffilani, H. Takaoka, and T. Tao. Transfer of energy to high frequencies in the cubic defocusing nonlinear Schrödinger equation. Invent. Math., 181(1):39¿113, 2010.