Infinite-dimensional representations of the rotation group and Dirac's monopole problem

Within the context of infinite-dimensional representations of the rotation group the Dirac monopole problem is studied in details. Irreducible infinite-dimensional representations, being realized in the indefinite metric Hilbert space, are given by linear unbounded operators in infinite-dimensional topological spaces, supplied with a weak topology and associated weak convergence. We argue that an arbitrary magnetic charge is allowed, and the Dirac quantization condition can be replaced by a generalized quantization rule yielding a new quantum number, the so-called topological spin, which is related to the weight of the Dirac string.Comment: JHEP style. Extended version of hep-th/0403146. Revised version, title and some notations are changed. References and Appendix B are adde

Cálculo de uma tarifa de alimentação para instalações fotovoltaicas residenciais na Colômbia

El objetivo de este artículo es estimar el valor de una tarifa de alimentación residencial que incentive la producción de energía fotovoltaica en Colombia. Para realizar este cálculo se aplica una metodología que combina el análisis de punto de equilibrio propuesto por Rigter y Vidican (2010), con la representación deuna instalación fotovoltaica diseñada en el programa Homer Energy. La tarifa de alimentación se calcula para tres ubicaciones en el país; en el caso de Bogotá, la tarifa es de 4359 pesos el kilovatio hora para un sistema fotovoltaico de 3 kW.Aunque la tarifa estimada puede parecer muy alta de acuerdo con las restricciones económicas e institucionales del Estado colombiano, hay espacio para explorar programas piloto y estructuras alternativas. El artículo también discute las barreras y las posibilidades legales para estimular las energías renovables en Colombia.The objective of this article is to estimate a residential feed-in rate that will encourage the production of photovoltaic energy in Colombia. For this calculation, the used methodology was one that combines the point of equilibrium analysis by Rigter and Vidican (2010) with the representation of a photovoltaic mechanism designed by the Homer Energy software. The feed-in rate is calculated for three different locations in the country, and for Bogota the rate is 4,359 pesos per kilowatt-hour for a 3 kW photovoltaic system. Even though the estimated rate can seem high according to the economic and institutional constrains of the Colombian State, the space to explore alternative mechanisms and pilot program sexists. The article also discusses the barriers and legal possibilities for stimulating of renewable energies in Colombia.O objetivo deste artigo é estimar o valor de uma de tarifa de alimentação residencial que incentive a produção de energia fotovoltaica na Colômbia. Para realizar este cálculo seaplica uma metodologia que combina a análise de ponto de equilíbrio proposto por Rigter e Vidican (2010), com a representação de uma instalação fotovoltaica desenhada no programa Homer Energy. A tarifa de alimentação se calcula para três localizações no país; no caso de Bogotá, a tarifa é de 4.359 pesos o quilowatt hora para um sistema fotovoltaico de 3 KW. Ainda que a tarifa estimada pode parecer muito alta de acordo às restrições econômicas e institucionais do Estado colombiano, há espaço para explorar programas piloto e estruturas alternativas. O artigo também discute as barreiras e as possibilidades legais para estimular as energias renováveis na Colômbia

3D to 2D transformation of environment and characters in videogames

Treball final de Grau en Disseny i Desenvolupament de Videojocs. Codi: VJ1241. Curs acadèmic: 2019/2020To use different programs and techniques to convert 3D character and scene modeling to 2D character and scenario modeling. To create several Demos that implement this technique with different uses, to observe its potential and possible error

Automating decision making to help establish norm-based regulations

Norms have been extensively proposed as coordination mechanisms for both agent and human societies. Nevertheless, choosing the norms to regulate a society is by no means straightforward. The reasons are twofold. First, the norms to choose from may not be independent (i.e, they can be related to each other). Second, different preference criteria may be applied when choosing the norms to enact. This paper advances the state of the art by modeling a series of decision-making problems that regulation authorities confront when choosing the policies to establish. In order to do so, we first identify three different norm relationships -namely, generalisation, exclusivity, and substitutability- and we then consider norm representation power, cost, and associated moral values as alternative preference criteria. Thereafter, we show that the decision-making problems faced by policy makers can be encoded as linear programs, and hence solved with the aid of state-of-the-art solvers

Online Automated Synthesis of Compact Normative Systems

Peer reviewedPostprin