http://www.recercat.cat:80/handle/2072/170956 Tue, 21 May 2013 10:13:27 GMT 2013-05-21T10:13:27Z http://www.recercat.cat:80/bitstream/id/34860/ http://www.recercat.cat:80/handle/2072/170956 http://www.recercat.cat:80/handle/2072/209201 Implementation of the Rijndael-AES algorithm on a Sage-Math worksheet Vicens Escuer, Albert La principal motivació d'aquest treball ha estat implementar l'algoritme Rijndael-AES en un full Sage-math, paquet de software matemàtic de lliure distribució i en actual desenvolupament, aprofitant les seves eines i funcionalitats integrades. http://www.recercat.cat:80/handle/2072/209201 http://www.recercat.cat:80/handle/2072/209196 Analysis of thermal properties of phase change materials (PCM) using differential scanning calorimeter (DSC) Sheth Karathia, Falguni Commercially available PCM RT 20, RT 27, SP 22, A17 and SP 25 A8. Were analyzed using dynamic and step method of heat flux DSC. The results of the dinamic and step method were compared with commercial valures. It was found that RT 20 & RT 27 showed good conforming of results with commercial values while SP 22 A17 & SP 25 A8 did not show conformity. Thu, 01 Sep 2011 00:00:00 GMT http://www.recercat.cat:80/handle/2072/209196 2011-09-01T00:00:00Z http://www.recercat.cat:80/handle/2072/209195 Compact thermal storage: a-state-of-the-art review of experimental results Cot Gores, Jaume Thermal energy storage (TES) can increase the thermal energy effieresa, of a process by reusing the waste heat from industrial process, solar energy or other sources. There are different ways to store thermal energy: by sensible heat, by latest heat, by sorption process or by chemical reaction. This thesrs provides a-state-of-the-art review of the experimental performance of TES systems based on solid gas sorption process and chemical reactions. The importance of theses processes is that provides a heat loss free storage system with a high energy density. Thu, 01 Sep 2011 00:00:00 GMT http://www.recercat.cat:80/handle/2072/209195 2011-09-01T00:00:00Z http://www.recercat.cat:80/handle/2072/209194 Design of PCM thermal storage unit for a HVAC system Moreno Argilés, Pere L'objectiu del projecte és el disseny d'una unitat d'emmagatzematge d'energia térmica que optimitzi i millori l'eficiència del sistema de climatització. Aquesta unitat contindrà materials de canvi de fase (PCM) per emmagatzemar l'energia i estarà acoblada a un sistema de climatització format per una bomba de calor i una unitat de tractament de l'aire. Thu, 01 Sep 2011 00:00:00 GMT http://www.recercat.cat:80/handle/2072/209194 2011-09-01T00:00:00Z http://www.recercat.cat:80/handle/2072/209197 Kumar's algorithm for solving Toeplitz systems of equations over finite fields Busom Figueres, Núria Adaptació de l'algorisme de Kumar per resoldre sistemes d'equacions amb matrius de Toeplitz sobre els reals a cossos finits en un temps 0 (n log n). Fri, 01 Jul 2011 00:00:00 GMT http://www.recercat.cat:80/handle/2072/209197 2011-07-01T00:00:00Z http://www.recercat.cat:80/handle/2072/209200 Life cycle analysis and life cyle impact assessment methodologies: a state of the art Ali Ibrahim Menoufi, Karim Life cycle analysis (LCA) is a comprehensive method for assessing the environmental impact of a product or an activity over its entire life cycle. The purpose of conducting LCA studies varies from one application to another. Different applications use LCA for different purposes. In general, the main aim of using LCA is to reduce the environmental impact of products through guiding the decision making process towards more sustainable solutions. The most critical phase in an LCA study is the Life Cycle Impact Assessment (LCIA) where the life cycle inventory (LCI) results of the considered substances related to the study of a certain system are transformed into understandable impact categories that represent the impact on the environment. In this research work, a general structure clarifying the steps that shall be followed ir order to conduct an LCA study effectively is presented. These steps are based on the ISO 14040 standard framework. In addition, a survey is done on the most widely used LCIA methodologies. Recommendations about possible developments and suggetions for further research work regarding the use of LCA and LCIA methodologies are discussed as well. Sun, 01 May 2011 00:00:00 GMT http://www.recercat.cat:80/handle/2072/209200 2011-05-01T00:00:00Z http://www.recercat.cat:80/handle/2072/209199 Improvement of the thermal performance of commercial freezers using phase change materials (PCM) Oró Prim, Eduard The aim of this work is to improve the thermal performance of commercial freezers using phase change materials (PCM) and the prove the importance of the correct PCM selection (melting temperature) for each application. To do this a vertical freezer with and without macro encapsulation PCM are used to assess the benefits of using PCM in minimizing temperature fluctuations and to maintain at the lowest possible temperature the freezer under heat of losses. Sun, 01 May 2011 00:00:00 GMT http://www.recercat.cat:80/handle/2072/209199 2011-05-01T00:00:00Z http://www.recercat.cat:80/handle/2072/209198 Numerical analysis of including phase change material in a domestic hot water cylinder Gracia Cuesta, Alvaro de The domestic hot water cylinder incorporates encapsulated pcm placed in 57 vertical pipes. The use of PCM increases the thermal energy storage capacity of the cylinder and allows the use of low cost electricity during low peak periods. After experimental validation the numerical model developed in the project will be used to optimize the distribution of the pcm inside the water tank. Sun, 01 May 2011 00:00:00 GMT http://www.recercat.cat:80/handle/2072/209198 2011-05-01T00:00:00Z