Spin-Peierls vs Peierls distortions in a family of conjugated polymers

Distortions in a family of conjugated polymers are studied using two complementary approaches: within a many-body valence bond approach using a transfer-matrix technique to treat the Heisenberg model of the systems, and also in terms of the tight-binding band-theoretic model with interactions limited to nearest neighbors. The computations indicate that both methods predict the presence or absence of the same distortions in most of the polymers studied.

Automatic Prediction of Facial Trait Judgments: Appearance vs. Structural Models

Evaluating other individuals with respect to personality characteristics plays a crucial role in human relations and it is the focus of attention for research in diverse fields such as psychology and interactive computer systems. In psychology, face perception has been recognized as a key component of this evaluation system. Multiple studies suggest that observers use face information to infer personality characteristics. Interactive computer systems are trying to take advantage of these findings and apply them to increase the natural aspect of interaction and to improve the performance of interactive computer systems. Here, we experimentally test whether the automatic prediction of facial trait judgments (e.g. dominance) can be made by using the full appearance information of the face and whether a reduced representation of its structure is sufficient. We evaluate two separate approaches: a holistic representation model using the facial appearance information and a structural model constructed from the relations among facial salient points. State of the art machine learning methods are applied to a) derive a facial trait judgment model from training data and b) predict a facial trait value for any face. Furthermore, we address the issue of whether there are specific structural relations among facial points that predict perception of facial traits. Experimental results over a set of labeled data (9 different trait evaluations) and classification rules (4 rules) suggest that a) prediction of perception of facial traits is learnable by both holistic and structural approaches; b) the most reliable prediction of facial trait judgments is obtained by certain type of holistic descriptions of the face appearance; and c) for some traits such as attractiveness and extroversion, there are relationships between specific structural features and social perceptions.

Usabilitat dels sistemes operatius en smartphones (Android vs iOS)

Aquest treball es portarà a terme realitzant una avaluació heurística dels sistmes operatius seleccionats i de les seves aplicacions, un test d'usabilitat i un anàlisi de l'organització de les funcions mitjançant un card sorting on-line.

Community structure in mediterranean shallow lentic ecosystems: size-based vs. taxon-based approaches

The main environmental variables determining the community structure and the functioning of Mediterranean shallow lentic ecosystems are described. These ecosystems are characterized by the unpredictability of their water inputs and the high variability in their water level and physical and chemical composition. Variations in flooding, salinity, and water turnover are determinant in species composition and nutrient dynamics. Taxon-based and size-based approaches to the study of the community structure of aquatic organisms that colonise these ecosystems are also compared. The conventional taxonomic approach, based on the determination of species composition, has been used for the identification of patterns in species richness, distribution and temporal dynamics, and for ecological requirements of species and their potential use as ecological indicators. This taxonbased approach has been compared with a size-based approach, where individuals are classified by their size. Size-based approach gives complementary information about community structure and dynamics, especially when communities are dominated by a single species. The use of size diversity combined with species diversity is suggested for a more complete understanding of community structuring in this type of ecosystem. Detailed examples of two Mediterranean shallow lentic ecosystems, the salt marshes of the Empordà wetlands and the Espolla temporary karstic pond, which differ in hydrology and water origin, are used to discuss the suitability of these different approaches

Standardized enforcement: Access to justice vs. contractual innovation

We model the effect of contract standardization on the development of markets andthe law. In a setting in which biased judges can distort contract enforcement, we findthat the introduction of a standard contract reduces enforcement distortions relative toreliance on precedents, exerting two effects: i) it statically expands the volume of trade,but ii) it crowds out the use of open-ended contracts, hindering legal evolution. We shedlight on the large-scale commercial codification undertaken in the nineteenth centuryin many countries (even common-law ones) during a period of booming commerce andlong-distance trade.

Anàlisi d'una conversa argumentativa: articles al diari Ara, Tresserras vs. Pastor

Aquest treball té per objecte l¿anàlisi d¿una ¿conversa¿ argumentativa ¿un conjunt de sis articles periodístics que conformen un macrotext¿, des del punt de vista del model pragmadialèctic. Els columnistes expressen els seus punts de vista al voltant de la "qüestió catalana", de vigència notable especialment d'ençà del setembre de 2012.

Estrategias de marcas del fabricante vs. marcas del distribuidor

La crisi econòmica d’aquests darrers anys ha marcat un important canvi en els hàbits de consum de les famílies espanyoles, aquestes han vist reduït el seu poder adquisitiu de forma significativa, la qual cosa s’ha traslladat directament al consum de productes en els supermercats. Davant aquesta situació, gran part dels consumidors s’han vist obligats a deixar de consumir “marques del fabricant”, i han passat a consumir “marques blanques” o “marques del distribuïdor”, amb la intenció de reduir la despesa familiar, intentant no alterar de forma significativa el seu nivell i qualitat de vida i la seva estabilitat econòmica.

Averting risk in the face of large losses: Bernoulli vs. Tversky and Kahneman

We experimentally question the assertion of Prospect Theory that people display risk attraction in choices involving high-probability losses. Indeed, our experimental participants tend to avoid fair risks for large (up to ? 90), high-probability (80%) losses. Our research hinges on a novel experimental method designed to alleviate the house-money bias that pervades experiments with real (not hypothetical) loses.Our results vindicate Daniel Bernoulli?s view that risk aversion is the dominant attitude,But, contrary to the Bernoulli-inspired canonical expected utility theory, we do find frequent risk attraction for small amounts of money at stake.In any event, we attempt neither to test expected utility versus nonexpected utility theories, nor to contribute to the important literature that estimates value and weighting functions. The question that we ask is more basic, namely: do people display risk aversion when facing large losses, or large gains? And, at the risk of oversimplifying, our answer is yes.

Rendiment acadèmic dels estudiants del Grau de Farmàcia segons la via d'accés als estudis (CGGS vs PAAU)

La nova ordenació dels ensenyaments universitaris i el desenvolupament dels graus ha comportat canvis en el perfil dels estudiants que arriben a les nostres aules. Un col·lectiu que té un pes específic important és el que accedeix a la universitat des d’una titulació de tècnic superior (cicle formatiu de grau superior – CFGS). Presentem les dades acadèmiques dels estudiants del Grau de Farmàcia des de la seva implantació el curs 2009-2010 fins el curs 2011-12, segons la seva via d’accés.

Rendiment acadèmic dels estudiants del Grau de Farmàcia segons la via d'accés als estudis (CGGS vs PAAU)

La nova ordenació dels ensenyaments universitaris i el desenvolupament dels graus ha comportat canvis en el perfil dels estudiants que arriben a les nostres aules. Un col·lectiu que té un pes específic important és el que accedeix a la universitat des d’una titulació de tècnic superior (cicle formatiu de grau superior – CFGS). Presentem les dades acadèmiques dels estudiants del Grau de Farmàcia des de la seva implantació el curs 2009-2010 fins el curs 2011-12, segons la seva via d’accés.

Anàlisi d'una conversa argumentativa : Articles al diari Ara, Tresserras vs. Pastor

Aquest treball té per objecte l'anàlisi d'una "conversa" argumentativa -un conjunt de sis articles periodístics que conformen un macrotext-, des del punt de vista del model pragmadialèctic. Els columnistes expressen els seus punts de vista al voltant de la "qüestió catalana", de vigència notable especialment d'ençà del setembre de 2012.

Estudi comparatiu de la publicació científica en l’àmbit de la informàtica a la UPC vs. altres universitats d’àmbit nacional i internacional (2002-2012)

L'estudi analitza la producció científica de la UPC vinculada amb la informàtica i es compara amb la d'altres 16 universitats de l’estat espanyol, europees, dels Estats Units i asiàtiques, amb una notable activitat investigadora en aquest camp.

Forecasting tourism demand to Catalonia: neural networks vs. time series models

The increasing interest aroused by more advanced forecasting techniques, together with the requirement for more accurate forecasts of tourismdemand at the destination level due to the constant growth of world tourism, has lead us to evaluate the forecasting performance of neural modelling relative to that of time seriesmethods at a regional level. Seasonality and volatility are important features of tourism data, which makes it a particularly favourable context in which to compare the forecasting performance of linear models to that of nonlinear alternative approaches. Pre-processed official statistical data of overnight stays and tourist arrivals fromall the different countries of origin to Catalonia from 2001 to 2009 is used in the study. When comparing the forecasting accuracy of the different techniques for different time horizons, autoregressive integrated moving average models outperform self-exciting threshold autoregressions and artificial neural network models, especially for shorter horizons. These results suggest that the there is a trade-off between the degree of pre-processing and the accuracy of the forecasts obtained with neural networks, which are more suitable in the presence of nonlinearity in the data. In spite of the significant differences between countries, which can be explained by different patterns of consumer behaviour,we also find that forecasts of tourist arrivals aremore accurate than forecasts of overnight stays.

Estudi comparatiu de la publicació científica de la UPC i l’ETSETB vs. altres universitats d’àmbit europeu (2002-2012)

L'informe es centra en la publicació científica especialitzada en l'àmbit temàtic propi de l'ETSETB: l'enginyeria de telecomunicacions i l'electrònica. Es comparen indicadors bibliomètrics de la UPC i l'ETSETB amb els d'altres universitats europees amb activitat de recerca notable en l'àrea de les telecomunicacions i l'electrònica.