Conversión hidrotermal de biomasa en bioproductos valiosos

Los procesos hidrotérmicos son una excelente alternativa para convertir desechos de biomasa en productos de alto valor energético. El alcance de este proyecto ofrece el estudio de 5 tipos de biomasa distintos: café, madera blanca, arroz, lignina y madera negra (Zilkha). La reacción se llevó a cabo en un reactor continúo cambiando las condiciones de presión y temperatura. El café demostró ser la materia primar de mayor rendimiento, alcanzando valores de hasta el 70% y, por el contrario, la lignina alcanzó muy bajos rendimientos, no sobrepasando el 13%. Para analizar el bioproducto solido obtenido se realizó un análisis termogravimétrico. A partir de estos datos, se propuso un nuevo método denominado ‘desplazamiento’ que refleja las diferencias entre los perfiles del producto sólido logrado y la biomasa no tratada. También se utilizaron técnicas de HPLC y MALDI-TOF-MS que demostraron mayores concentraciones en los bioproductos líquidos obtenidos según aumentaba la temperatura de reacción.University of NottinghamGrado en Ingeniería Químic

Effective retrieval and new indexing method for case based reasoning: Application in chemical process design

In this paper we try to improve the retrieval step for case based reasoning for preliminary design. This improvement deals with three major parts of our CBR system. First, in the preliminary design step, some uncertainties like imprecise or unknown values remain in the description of the problem, because they need a deeper analysis to be withdrawn. To deal with this issue, the faced problem description is soften with the fuzzy sets theory. Features are described with a central value, a percentage of imprecision and a relation with respect to the central value. These additional data allow us to build a domain of possible values for each attributes. With this representation, the calculation of the similarity function is impacted, thus the characteristic function is used to calculate the local similarity between two features. Second, we focus our attention on the main goal of the retrieve step in CBR to find relevant cases for adaptation. In this second part, we discuss the assumption of similarity to find the more appropriated case. We put in highlight that in some situations this classical similarity must be improved with further knowledge to facilitate case adaptation. To avoid failure during the adaptation step, we implement a method that couples similarity measurement with adaptability one, in order to approximate the cases utility more accurately. The latter gives deeper information for the reusing of cases. In a last part, we present a generic indexing technique for the base, and a new algorithm for the research of relevant cases in the memory. The sphere indexing algorithm is a domain independent index that has performances equivalent to the decision tree ones. But its main strength is that it puts the current problem in the center of the research area avoiding boundaries issues. All these points are discussed and exemplified through the preliminary design of a chemical engineering unit operation

Lights and shadows of contemporary North Americansociological debate on ethnic entrepreneurship

[Resumo] Este artigo ten como obxectivo realizar un percorrido polas formulacións (e reformulacións)máis significativas da socioloxía norteamericana contemporánea do emprendedorismo étnico,así como analizar a súa capacidade para explicar do punto de vista sociolóxico o fenómeno das redes empresariais das poboacións etnicamente minoritarias. A nosa hipótese de traballo sostén que nas principais aproximacións da socioloxía do emprendedorismo étnico norteamericana, a pesar da heteroxeneidade das súas propostas, existen lugares comúns quevan para alén de compartiren un mesmo obxecto formal de estudo. Estes lugares comúns(afinidade, comunitarismo, excepcionalidade étnica) implicarían importantes limitacións explicativas (inmediatismo, culturalismo, etnificación) que as distintas reformulacións efectuadas puideron lograr puír, mais non facer desaparecer. Os sucesivos desprazamentos dos termos do debate, malia a indubidable apertura que supuxeron, volven reproducir algunhas destas limitacións.[Abstract] The aim of this article is to examine the most significant formulations and reformulations of North American contemporary sociology of ethnic entrepreneurship, analysing their capacityto provide an explanation in sociological terms for the entrepreneurial networks of minorityethnic groups. Our working hypothesis is that, despite the varying nature of their proposals, the main approaches of the North American sociology of ethnic entrepreneurship share certain features beyond the fact that they deal with the same area of study. These common features(affinity, communitarism, ethnic exception) involve major explanatory limitations (culturalism,ethnification and a focus on the present or presentism) and, although various reformulationshave attempted to counteract them, they have not succeeded in eliminating them completely. Successive changes in the terms used to discuss the topic have undoubtedly opened up the subject but some of the same limitations recur

Generalized Platform for Creating of Testing Games

The thesis is an extension and a generalization of a previous theses done by Antonio Carro and Eduard Martínez. The goal of this work is to create a virtual platform where the teachers will be able to define different structures for the tests,create tests and follow the students progress. This virtual platform will have an architecture of server-client allowing the platform independence and the future development of mobile clients also the possible integration of other e-learning platforms in the market. The main programming languages will be PHP, Javascriptii, CSS for the Internet platform and web services