Empirical mode decomposition-based face recognition system

In this work we explore the multivariate empirical mode decomposition combined with a Neural Network classifier as technique for face recognition tasks. Images are simultaneously decomposed by means of EMD and then the distance between the modes of the image and the modes of the representative image of each class is calculated using three different distance measures. Then, a neural network is trained using 10- fold cross validation in order to derive a classifier. Preliminary results (over 98 % of classification rate) are satisfactory and will justify a deep investigation on how to apply mEMD for face recognition.

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.

Rockfall monitoring by Terrestrial Laser Scanning ¿ case study of the basaltic rock face at Castellfollit de la Roca (Catalonia, Spain)

This case study deals with a rock face monitoring in urban areas using a Terrestrial Laser Scanner. The pilot study area is an almost vertical, fifty meter high cliff, on top of which the village of Castellfollit de la Roca is located. Rockfall activity is currently causing a retreat of the rock face, which may endanger the houses located at its edge. TLS datasets consist of high density 3-D point clouds acquired from five stations, nine times in a time span of 22 months (from March 2006 to January 2008). The change detection, i.e. rockfalls, was performed through a sequential comparison of datasets. Two types of mass movement were detected in the monitoring period: (a) detachment of single basaltic columns, with magnitudes below 1.5 m3 and (b) detachment of groups of columns, with magnitudes of 1.5 to 150 m3. Furthermore, the historical record revealed (c) the occurrence of slab failures with magnitudes higher than 150 m3. Displacements of a likely slab failure were measured, suggesting an apparent stationary stage. Even failures are clearly episodic, our results, together with the study of the historical record, enabled us to estimate a mean detachment of material from 46 to 91.5 m3 year¿1. The application of TLS considerably improved our understanding of rockfall phenomena in the study area.

Beyond the Net Generation debate: A comparison between digital learners in face-to-face and virtual universities

This paper is based on the hypothesis that the use of technology to support learning is not related to whether a student belongs to the Net Generation, but that it is mainly influenced by the teaching model. The study compares behaviour and preferences towards ICT use in two groups of university students: face-to-face students and online students. A questionnaire was applied to asample of students from five universities with different characteristics (one offers online education and four offer face-to-face education with LMS teaching support).

Visualizing key authenticity: turning your face into your public key

La informació biomètrica s'ha convertit en una tecnologia complementària a la criptografia que permet administrar còmodament les dades criptogràfiques. Són útils dues necessitats importants: en primer lloc, posar aquestes dades sempre a mà i, a més, fent fàcilment identificable el seu legítim propietari. En aquest article es proposa un sistema que integra la signatura biomètrica de reconeixement facial amb un esquema de signatura basat en la identitat, de manera que la cara de l'usuari esdevé la seva clau pública i la ID del sistema. D'aquesta manera, altres usuaris poden verificar els missatges utilitzant fotos del remitent, proporcionant un intercanvi raonable entre la seguretat del sistema i la usabilitat, així com una manera molt més senzilla d'autenticar claus públiques i processos de distribució.

El primer liberalismo y las pautas de resistencia tradicional en Lleida (1833-1868)

Lleida, una ciudad media de España en el XIX que tiene como particularidad ser una capital de provincia con una economía tradicional a medio camino entre las actividades del campo y las incipientes urbanas, es nuestro marco de estudio para analizar el comportamiento de los grupos sociales de su comunidad ante los cambios políticos operados en España durante el siglo XIX para consolidar el liberalismo como sistema de gobierno. Las fuentes consultadas fueron los archivos locales mediante el contraste de los censos de población, sus rentas y la lista de políticos y milicianos implicados en el proceso político para establecer pautas y analogías entre ellos según su filiación política. Con estas pautas nos acercamos a la sociología de su población y sus concreciones políticas durante este período. De esta manera, descubrimos los mecanismos de resistencia del grupo dominante del antiguo régimen para mantener el poder y las tácticas de los liberales para conseguir desbancarlos y conseguir mayor representación política en el municipio. La conclusión de este estudio es que mediante el acomodo de los grupos privilegiados del antiguo régimen al liberalismo moderado, estos consiguieron su espacio político en la comunidad para mantener la mayor parte del tiempo su cuota de poder, mientras que los liberales, mediante su identificación al progresismo, tenían enormes dificultades para conseguir el control y poner en práctica su proyecto político.

Preferred Spatial Frequencies for Human Face Processing Are Associated with Optimal Class Discrimination in the Machine

Psychophysical studies suggest that humans preferentially use a narrow band of low spatial frequencies for face recognition. Here we asked whether artificial face recognition systems have an improved recognition performance at the same spatial frequencies as humans. To this end, we estimated recognition performance over a large database of face images by computing three discriminability measures: Fisher Linear Discriminant Analysis, Non-Parametric Discriminant Analysis, and Mutual Information. In order to address frequency dependence, discriminabilities were measured as a function of (filtered) image size. All three measures revealed a maximum at the same image sizes, where the spatial frequency content corresponds to the psychophysical found frequencies. Our results therefore support the notion that the critical band of spatial frequencies for face recognition in humans and machines follows from inherent properties of face images, and that the use of these frequencies is associated with optimal face recognition performance.

A nursing interface terminology: evaluation of face validity

A range of different language systems for nursing diagnosis, interventions and outcomes are currently available. Nursing terminologies are intended to support nursing practice but they have to be evaluated. This study aims to assess the results of an expert survey to establish the face validity of a nursing interface terminology. The study applied a descriptive design with a cross-sectional survey strategy using a written questionnaire administered to expert nurses working in hospitals. Sample size was estimated at 35 participants. The questionnaire included topics related to validity and reliability criteria for nursing controlled vocabularies described in the literature. Mean global score and criteria scoring at least 7 were considered main outcome measures. The analysis included descriptive statistics with a confidence level of 95%. The mean global score was 8.1. The mean score for the validity criteria was 8.4 and 7.8 for reliability and applicability criteria. Two of the criteria for reliability and applicability evaluation did not achieve minimum scores. According to the experts" responses, this terminology meets face validity, but that improvements are required in some criteria and further research is needed to completely demonstrate its metric properties.

Beyond the net generation debate: A comparison of digital learners in face-to-face and virtual universities

In the last decade, an important debate has arisen about the characteristics of today"s students due to their intensive experience as users of ICT. The main belief is that frequent use of technologies in everyday life implies that competent users are able to transfer their digital skills to learning activities. However, empirical studies developed in different countries reveal similar results suggesting that the"digital native" label does not provide evidence of a better use of technology to support learning. The debate has to go beyond the characteristics of the new generation and focus on the implications of being a learner in a digitalised world. This paper is based on the hypothesis that the use of technology to support learning is not related to whether a student belongs to the Net Generation, but that it is mainly influenced by the teaching model. The study compares behaviour and preferences towards ICT use in two groups of university students: face-to-face students and online students. A questionnaire was applied to a sample of students from five universities with different characteristics (one offers online education and four offer face-to-face education with LMS teaching support). Findings suggest that although access to and use of ICT is widespread, the influence of teaching methodology is very decisive. For academic purposes, students seem to respond to the requirements of their courses, programmes, and universities. There is a clear relationship between students" perception of usefulness regarding certain ICT resources and their teachers" suggested uses of technologies. The most highly rated technologies correspond with those proposed by teachers. The study shows that the educational model (face-to-face or online) has a stronger influence on students" perception of usefulness regarding ICT support for learning than the fact of being a digital native.

Fluid flow processes at basin scale

S u b s u r face fluid flow plays a significant role in many geologic processes and is increasingly being studied in the scale of sedimentary basins and geologic time perspective. Many economic resources such as petroleum and mineral deposits are products of basin scale fluid flow operating over large periods of time. Such ancient flow systems can be studied through analysis of diagenetic alterations and fluid inclusions to constrain physical and chemical conditions of fluids and rocks during their paleohy d r og e o l ogic evolution. Basin simulation models are useful to complement the paleohy d r og e o l ogic record preserved in the rocks and to derive conceptual models on hydraulic basin evolution and generation of economic resources. Different types of fluid flow regimes may evo l ve during basin evolution. The most important with respect to flow rates and capacity for transport of solutes and thermal energy is gr avitational fluid flow driven by the topographic configuration of a basin. Such flow systems require the basin to be elevated above sea level. Consolidational fluid flow is the principal fluid migration process in basins below sea level, caused by loading of compressible rocks. Flow rates of such systems are several orders of magnitude below topogr a p hy driven flow. Howeve r, consolidation may create significant fluid ove rpressure. Episodic dewatering of ove rpressured compart m e n t s m ay cause sudden fluid release with elevated flow velocities and may cause a transient local thermal and chemical disequilibrium betwe e n fluid and rock. This paper gives an ove rv i ew on subsurface fluid flow processes at basin scale and presents examples related to the Pe n e d è s basin in the central Catalan continental margin including the offshore Barcelona half-graben and the compressive South-Pyrenean basin.

Shared feature extraction for nearest neighbor face recognition

In this paper, we propose a new supervised linearfeature extraction technique for multiclass classification problemsthat is specially suited to the nearest neighbor classifier (NN).The problem of finding the optimal linear projection matrix isdefined as a classification problem and the Adaboost algorithmis used to compute it in an iterative way. This strategy allowsthe introduction of a multitask learning (MTL) criterion in themethod and results in a solution that makes no assumptions aboutthe data distribution and that is specially appropriated to solvethe small sample size problem. The performance of the methodis illustrated by an application to the face recognition problem.The experiments show that the representation obtained followingthe multitask approach improves the classic feature extractionalgorithms when using the NN classifier, especially when we havea few examples from each class

L' Impacte de la mort en estudiants d'infermeria durant el seu primer període de pràctiques

La mort i el procés de morir són fets quotidians en les persones grans i, conseqüentment, en els centres sociosanitaris, on bona part de les persones usuàries són d’edat avançada. Tot i que es tracta d’un fenomen natural que s’inclou dins del cicle vital de les persones, en la nostra societat la mort encara provoca rebuig, por, ansietat, tristesa i inquietud. En aquest marc, les estudiants1 d’infermeria són un col·lectiu que poden patir especialment l’impacte de la mort. Primer, perquè com a membres de la societat tenen interioritzat el codi social preestablert envers aquest tema i, segon, perquè durant la seva formació estan en contacte amb persones que estan al final de la vida i poden presenciar vivències de mort. En el primer període de pràctiques dels estudis d’infermeria, les estudiants han de fer front a diverses situacions del dia a dia fins aleshores desconegudes. Els conflictes interpersonals amb l'equip de treball i la inseguretat sobre les habilitats i les competències professionals són alguns dels aspectes que acostumen a viure amb més tensió. Tot i això, el que més impacte els provoca és la cura de les persones al final de la vida. Davant d'una situació de tensió, la persona viu un component estressor, que suposa el punt d’inflexió. A partir d’aquí s’activen els components adaptatius, que és el que emocionalment fa que la persona pugui fer front a aquesta situació estressant. A més, hi ha un component de suport, que són les ajudes que té. Segons com es treballi el component adaptatiu farà que la persona reaccioni en un futur de forma més automàtica i inconscient o, al contrari, que la persona respongui de forma més conscient i intencionada. El present treball està concebut per comprendre quins elements psicosocials – components estressors i components de suport– poden afectar a les estudiants que presencien la vivència de la mort de malalts geriàtrics terminals en el primer període de pràctiques en un centre sociosanitari. S’ha dissenyat un estudi descriptiu transversal quantitatiu, de caràcter exploratori, per tal de descriure la freqüència i algunes característiques psicosocials al voltant de la mort en estudiants d'infermeria en el seu primer període de pràctiques, tant a nivell personal com a nivell professional. La mostra de l'estudi són 65 estudiants, la majoria són dones d'entre els 18 i els 29 anys –més d’un 90%–. Els resultats indiquen que un 80% dels futurs professionals estudiats han patit la mort d’alguna persona significativa al llarg de la seva vida; d'aquests, gairebé un de cada quatre presenta dol complicat. Quant a la vivència de mort en les pràctiques, el 83% l'ha experimentat. Tot i aquest elevat percentatge, no totes les experiències tenen una connotació negativa. En prop de la meitat dels casos, les morts són percebudes com una experiència enriquidora i natural. Els components estressors més impactants que les estudiants han viscut durant les pràctiques per la mort d’alguna persona malalta són: la reacció de la família del finat, el patiment que es genera al seu voltant, algun signe o símptoma físic experimentat pel malalt al final del procés, i la pròpia reacció emocional. Els components de suport expressats són: saber gestionar les pròpies emocions, tenir més formació sobre relació d’ ajuda i empatia, tenir més formació en control de símptomes i comunicació, per atendre usuaris –tant malalts com familiars- i que algú els informés i orientés en el procés. Altres resultats a tenir en compte són que la població estudiada té més preocupació o inquietud per la mort i el procés de morir de la persona estimada i menys per la pròpia mort. A més, tot i que la meitat no hagués escollit geriatria com opció a les primeres pràctiques clíniques, gairebé tot el grup estudiat ho recomanaria després d'haver viscut l'experiència. Les implicacions pràctiques d'aquest estudi porten a pensar que es pot reorientar la informació i preparació que es dóna a les estudiants d’infermeria abans del primer contacte amb la realitat dels centres sociosanitaris, així com també el paper de formació i suport que pot fer tant la persona tutora de pràctiques com les infermeres de referència dels diferents centres. En conclusió, caldria dissenyar estratègies formatives i de suport entorn a la preparació psicològica personal de l’estudiant; entorn a l’acompanyament, les cures pal·liatives i el dol; i valorar la seva eficiència en el futur.