60 resultados para operational semantics


Relevância:

20.00% 20.00%

Publicador:

Resumo:

La empresa moderna, se encuentra en una situación actual de incertidumbre en la que además está más expuesta a factores externos con el aumento de la competencia y el impacto de la globalización. Se enfrenta a un panorama que debe ser gestionado adecuadamente para asegurar su supervivencia y el éxito de su existencia. En este TFC, se presenta una de las herramientas ‘buque insignia’ del Management moderno, aquella que está destinada a ser la base de la Gestión de la empresa y que cada vez más se hace imprescindible para la construcción de un futuro cada vez más incierto, la Planificación Estratégica. El Plan Estratégico 2012-2015 de AESL se desarrolla en varios apartados que intentarán dar con las claves de la dirección que la empresa debe seguir y propone los objetivos que encontrará a través de la puesta en marcha de las acciones y estrategias determinadas. La primera etapa, y la más extensa, realiza un Análisis de la situación externa e interna de la empresa además de un Diagnóstico de la misma. Se analizan diversos factores que pueden contribuir o hacer peligrar el futuro de la empresa, y constituye el punto de partida de la planificación. En la segunda etapa, y con la información de la anterior fase, comienza la fijación de los Objetivos Corporativos y la definición de las Decisiones Estratégicas que han de transformar nuestro rumbo actual en el logro de esos objetivos. Las estrategias no sólo comportarán un ámbito corporativo, también se centrarán en estrategias funcionales con un carácter más definitorio en el interior de la empresa. Por último, la tercera y última etapa, aglutinará todas estas Decisiones estratégicas para transformarlas en las Decisiones Operativas, aquellas que se encargarán de gestionar el día a día de la empresa a través de los Planes de Acción, que suponen la etapa de mayor concreción del Plan. Este Plan a 3 años deberá erigirse como la herramienta de planificación más importante de la empresa, debiendo guiar las principales decisiones tomadas y convirtiéndose en un instrumento de consulta no sólo para decidir hoy lo que se hará en el futuro sino también para mantener unos niveles altos de competitividad en el tremendo esfuerzo que supone la gestión de una PYME.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In the scope of the European project Hydroptimet, INTERREG IIIB-MEDOCC programme, limited area model (LAM) intercomparison of intense events that produced many damages to people and territory is performed. As the comparison is limited to single case studies, the work is not meant to provide a measure of the different models' skill, but to identify the key model factors useful to give a good forecast on such a kind of meteorological phenomena. This work focuses on the Spanish flash-flood event, also known as "Montserrat-2000" event. The study is performed using forecast data from seven operational LAMs, placed at partners' disposal via the Hydroptimet ftp site, and observed data from Catalonia rain gauge network. To improve the event analysis, satellite rainfall estimates have been also considered. For statistical evaluation of quantitative precipitation forecasts (QPFs), several non-parametric skill scores based on contingency tables have been used. Furthermore, for each model run it has been possible to identify Catalonia regions affected by misses and false alarms using contingency table elements. Moreover, the standard "eyeball" analysis of forecast and observed precipitation fields has been supported by the use of a state-of-the-art diagnostic method, the contiguous rain area (CRA) analysis. This method allows to quantify the spatial shift forecast error and to identify the error sources that affected each model forecasts. High-resolution modelling and domain size seem to have a key role for providing a skillful forecast. Further work is needed to support this statement, including verification using a wider observational data set.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Ground clutter caused by anomalous propagation (anaprop) can affect seriously radar rain rate estimates, particularly in fully automatic radar processing systems, and, if not filtered, can produce frequent false alarms. A statistical study of anomalous propagation detected from two operational C-band radars in the northern Italian region of Emilia Romagna is discussed, paying particular attention to its diurnal and seasonal variability. The analysis shows a high incidence of anaprop in summer, mainly in the morning and evening, due to the humid and hot summer climate of the Po Valley, particularly in the coastal zone. Thereafter, a comparison between different techniques and datasets to retrieve the vertical profile of the refractive index gradient in the boundary layer is also presented. In particular, their capability to detect anomalous propagation conditions is compared. Furthermore, beam path trajectories are simulated using a multilayer ray-tracing model and the influence of the propagation conditions on the beam trajectory and shape is examined. High resolution radiosounding data are identified as the best available dataset to reproduce accurately the local propagation conditions, while lower resolution standard TEMP data suffers from interpolation degradation and Numerical Weather Prediction model data (Lokal Model) are able to retrieve a tendency to superrefraction but not to detect ducting conditions. Observing the ray tracing of the centre, lower and upper limits of the radar antenna 3-dB half-power main beam lobe it is concluded that ducting layers produce a change in the measured volume and in the power distribution that can lead to an additional error in the reflectivity estimate and, subsequently, in the estimated rainfall rate.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Weather radar observations are currently the most reliable method for remote sensing of precipitation. However, a number of factors affect the quality of radar observations and may limit seriously automated quantitative applications of radar precipitation estimates such as those required in Numerical Weather Prediction (NWP) data assimilation or in hydrological models. In this paper, a technique to correct two different problems typically present in radar data is presented and evaluated. The aspects dealt with are non-precipitating echoes - caused either by permanent ground clutter or by anomalous propagation of the radar beam (anaprop echoes) - and also topographical beam blockage. The correction technique is based in the computation of realistic beam propagation trajectories based upon recent radiosonde observations instead of assuming standard radio propagation conditions. The correction consists of three different steps: 1) calculation of a Dynamic Elevation Map which provides the minimum clutter-free antenna elevation for each pixel within the radar coverage; 2) correction for residual anaprop, checking the vertical reflectivity gradients within the radar volume; and 3) topographical beam blockage estimation and correction using a geometric optics approach. The technique is evaluated with four case studies in the region of the Po Valley (N Italy) using a C-band Doppler radar and a network of raingauges providing hourly precipitation measurements. The case studies cover different seasons, different radio propagation conditions and also stratiform and convective precipitation type events. After applying the proposed correction, a comparison of the radar precipitation estimates with raingauges indicates a general reduction in both the root mean squared error and the fractional error variance indicating the efficiency and robustness of the procedure. Moreover, the technique presented is not computationally expensive so it seems well suited to be implemented in an operational environment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Monitoring thunderstorms activity is an essential part of operational weather surveillance given their potential hazards, including lightning, hail, heavy rainfall, strong winds or even tornadoes. This study has two main objectives: firstly, the description of a methodology, based on radar and total lightning data to characterise thunderstorms in real-time; secondly, the application of this methodology to 66 thunderstorms that affected Catalonia (NE Spain) in the summer of 2006. An object-oriented tracking procedure is employed, where different observation data types generate four different types of objects (radar 1-km CAPPI reflectivity composites, radar reflectivity volumetric data, cloud-to-ground lightning data and intra-cloud lightning data). In the framework proposed, these objects are the building blocks of a higher level object, the thunderstorm. The methodology is demonstrated with a dataset of thunderstorms whose main characteristics, along the complete life cycle of the convective structures (development, maturity and dissipation), are described statistically. The development and dissipation stages present similar durations in most cases examined. On the contrary, the duration of the maturity phase is much more variable and related to the thunderstorm intensity, defined here in terms of lightning flash rate. Most of the activity of IC and CG flashes is registered in the maturity stage. In the development stage little CG flashes are observed (2% to 5%), while for the dissipation phase is possible to observe a few more CG flashes (10% to 15%). Additionally, a selection of thunderstorms is used to examine general life cycle patterns, obtained from the analysis of normalized (with respect to thunderstorm total duration and maximum value of variables considered) thunderstorm parameters. Among other findings, the study indicates that the normalized duration of the three stages of thunderstorm life cycle is similar in most thunderstorms, with the longest duration corresponding to the maturity stage (approximately 80% of the total time).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The current operational very short-term and short-term quantitative precipitation forecast (QPF) at the Meteorological Service of Catalonia (SMC) is made by three different methodologies: Advection of the radar reflectivity field (ADV), Identification, tracking and forecasting of convective structures (CST) and numerical weather prediction (NWP) models using observational data assimilation (radar, satellite, etc.). These precipitation forecasts have different characteristics, lead time and spatial resolutions. The objective of this study is to combine these methods in order to obtain a single and optimized QPF at each lead time. This combination (blending) of the radar forecast (ADV and CST) and precipitation forecast from NWP model is carried out by means of different methodologies according to the prediction horizon. Firstly, in order to take advantage of the rainfall location and intensity from radar observations, a phase correction technique is applied to the NWP output to derive an additional corrected forecast (MCO). To select the best precipitation estimation in the first and second hour (t+1 h and t+2 h), the information from radar advection (ADV) and the corrected outputs from the model (MCO) are mixed by using different weights, which vary dynamically, according to indexes that quantify the quality of these predictions. This procedure has the ability to integrate the skill of rainfall location and patterns that are given by the advection of radar reflectivity field with the capacity of generating new precipitation areas from the NWP models. From the third hour (t+3 h), as radar-based forecasting has generally low skills, only the quantitative precipitation forecast from model is used. This blending of different sources of prediction is verified for different types of episodes (convective, moderately convective and stratiform) to obtain a robust methodology for implementing it in an operational and dynamic way.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper we highlight the importance of the operational costs in explaining economic growth and analyze how the industrial structure affects the growth rate of the economy. If there is monopolistic competition only in an intermediate goods sector, then production growth coincides with consumption growth. Moreover, the pattern of growth depends on the particular form of the operational cost. If the monopolistically competitive sector is the final goods sector, then per capita production is constant but per capita effective consumption or welfare grows. Finally, we modify again the industrial structure of the economy and show an economy with two different growth speeds, one for production and another for effective consumption. Thus, both the operational cost and the particular structure of the sector that produces the final goods determines ultimately the pattern of growth.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper we highlight the importance of the operational costs in explaining economic growth and analyze how the industrial structure affects the growth rate of the economy. If there is monopolistic competition only in an intermediate goods sector, then production growth coincides with consumption growth. Moreover, the pattern of growth depends on the particular form of the operational cost. If the monopolistically competitive sector is the final goods sector, then per capita production is constant but per capita effective consumption or welfare grows. Finally, we modify again the industrial structure of the economy and show an economy with two different growth speeds, one for production and another for effective consumption. Thus, both the operational cost and the particular structure of the sector that produces the final goods determines ultimately the pattern of growth.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

La producció de biopolímers (polihidroxialcanoats (PHA) i substàncies polimèriques extracel·lulars (EPS)) a nivell industrial, resulta una nova àrea d’investigació que recull diverses disciplines, entre elles les Ciències Ambientals. Aquest projecte final de carrera amb el títol: “Producció de biopolímers amb cultius bacterians mixtes”, s’ha desenvolupat sota la supervisió de la directora de projecte Dra. María Eugenia Suárez Ojeda del Departament d’Enginyeria Química de la Universitat Autònoma de Barcelona (UAB) i s’ha dut a terme per l’estudiant Jordi Pérez i Forner de la Llicenciatura de Ciències Ambientals, Facultat de Ciències de la UAB, en el Departament d’Enginyeria Química de la mateixa universitat. L’objectiu d’aquest projecte ha estat produir biopolímers simultàniament amb l’eliminació de fòsfor i matèria orgànica en aigües residuals per obtenir un residu final amb un alt valor afegit. Aquests biopolímers reuneixen les característiques necessàries per a poder competir amb els plàstics convencionals i així, reduir l’elevat consum del petroli i la generació de residus no biodegradables. En aquest projecte s’ha dut a terme la posta en marxa d’un reactor discontinu seqüencial (SBR) per a l’acumulació de biopolímers amb cultius bacterians mixtes. Diferents investigadors han estudiat que aquests tipus de cultius bacterians arriben a nivells de fins el 53-97% [Pijuan et al., 2009] de contingut de biopolímers a la biomassa, sometent als microorganismes a diferents situacions d’estrés ja sigui per dèficit de nutrients o per variacions en les fases de feast-famine (festí-fam). Durant el projecte, s’ha realitzat el monitoratge del reactor alimentat amb una aigua sintètica, elaborada en el laboratori, amb les característiques d’un aigua residual provinent de la industria làctica. S’ha sotmès als microorganismes a diferents condicions operacionals, una d’elles amb limitació de fòsfor com a nutrient i una tercera condició amb una variació a les fases feast-famine. D’altra banda, com a segon objectiu, s’ha analitzat el contingut de biopolímers a la biomassa de dos SBRs més, del grup de recerca Bio-GLS del Departament d’Enginyeria Química de la UAB, alimentats amb diferents fonts de carboni, glicerol i àcids grassos de cadena llarga (AGCLL), per observar les influències que té el tipus de substrat en l’acumulació de biopolímers. Els resultats obtinguts en la primera part d’aquest projecte han estat similars als resultats d’altres investigadors [Pijuan et al., 2009; Guerrero et al., 2012]. S’ha determinat que sotmetre als microorganismes a situacions d’estrés té un efecte directe pel que fa a l’acumulació de biopolímers. També s’ha observat com al mateix temps que acumulaven aquests compostos, els microorganismes desenvolupaven la seva tasca de depurar l’aigua residual, obtenint al final del cicle una aigua amb un baix contingut en matèria orgànica i altres contaminants com amoni i fòsfor, en aquest cas. En la segona part del projecte, s’ha observat com el tipus de substrat té un efecte directe pel que fa a l’acumulació de biopolímers i també a l’activitat metabòlica dels microorganismes. Per tant, s’ha conclòs que la producció de biopolímers mitjançant la depuració d’aigües residuals es una via d’investigació molt prometedora pel que fa als resultats obtinguts. Alhora que es tracta un residu, s’obté una producte residual amb un alt valor afegit que pot ser utilitzat per la producció de bioplàstics 100% biodegradables.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The relation between the low-energy constants appearing in the effective field theory description of the Lambda N -> NN transition potential and the parameters of the one-meson-exchange model previously developed is obtained. We extract the relative importance of the different exchange mechanisms included in the meson picture by means of a comparison to the corresponding operational structures appearing in the effective approach. The ability of this procedure to obtain the weak baryon-baryon-meson couplings for a possible scalar exchange is also discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The relation between the low-energy constants appearing in the effective field theory description of the Lambda N -> NN transition potential and the parameters of the one-meson-exchange model previously developed is obtained. We extract the relative importance of the different exchange mechanisms included in the meson picture by means of a comparison to the corresponding operational structures appearing in the effective approach. The ability of this procedure to obtain the weak baryon-baryon-meson couplings for a possible scalar exchange is also discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Web 2.0 services such as social bookmarking allow users to manage and share the links they find interesting, adding their own tags for describingthem. This is especially interesting in the field of open educational resources, asdelicious is a simple way to bridge the institutional point of view (i.e. learningobject repositories) with the individual one (i.e. personal collections), thuspromoting the discovering and sharing of such resources by other users. In this paper we propose a methodology for analyzing such tags in order to discover hidden semantics (i.e. taxonomies and vocabularies) that can be used toimprove descriptions of learning objects and make learning object repositories more visible and discoverable. We propose the use of a simple statistical analysis tool such as principal component analysis to discover which tags createclusters that can be semantically interpreted. We will compare the obtained results with a collection of resources related to open educational resources, in order to better understand the real needs of people searching for open educational resources.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper contributes to the literature by applying the Granger causality approach and endogenous breakpoint test to offer an operational definition of contagion to examine European Economic and Monetary Union (EMU) countries public debt behaviour. A database of yields on 10-year government bonds issued by 11 EMU countries covering fourteen years of monetary union is used. The main results suggest that the 41 new causality patterns, which appeared for the first time in the crisis period, and the intensification of causality recorded in 70% of the cases, provide clear evidence of contagion in the aftermath of the current euro debt crisis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Awareness is required for supporting all forms of cooperation. In Computer Supported Collaborative Learning (CSCL), awareness can be used for enhancing collaborative opportunities across physical distances and in computer-mediated environments. Shared Knowledge Awareness (SKA) intends to increase the perception about the shared knowledge, students have in a collaborative learning scenario and also concerns the understanding that this group has about it. However, it is very difficult to produce accurate awareness indicators based on informal message exchange among the participants. Therefore, we propose a semantic system for cooperation that makes use of formal methods for knowledge representation based on semantic web technologies. From these semantics-enhanced repository and messages, it could be easier to compute more accurate awareness.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present work is aimed at reporting an educational experience about the conservation of the substance and the cognitive theories of Jean Piaget & Lev S. Vygotsky. This activity was carried out with 1st course students in the practical classes of the subject called Psicologia de l"educació i del desenvolupament en l"edat escolar, within the Teacher Training studies of the University of Girona. This experience was inspired by a proposal of González, Fuentes, de la Morena and Barajas (1995), in which the students have to analyse, using the solid and liquid conservation tasks created by Piaget and his colleagues from the Genevan School, the transition from the preoperational to the operational thought in infants aged from 4 to 8. This proposal has been adapted in order to analyse not only the infants" level of cognitive development but also what they can learn with the help of another person. Consequently, the students have chosen, administered and evaluated the support given to the children. Additionally, the different strategies used by the students in order to promote the infants" comprehension of the conservation have been studied and classified, which has allowed the reflection about other possible methods to teach and to show how to teach this concept El present treball pretén explicar una experiència docent sobre la conservació de la substància i les teories cognitives de Jean Piaget i Lev S. Vygotsky, en el marc de les pràctiques de l"assignatura Psicologia de l"educació i del desenvolupament en l"edat escolar amb alumnes 1r curs de la Diplomatura de Magisteri de la Universitat de Girona. Aquesta experiència s"ha inspirat en una proposta de González, Fuentes, de la Morena i Barajas (1995), en la qual els alumnes han d"analitzar el pas del pensament preoperatori al pensament operatori en infants de 4 a 8 anys, a través de tasques de conservació de la substància sòlida i líquida, les quals ja foren utilitzades per Piaget i els seus col·laboradors de l"Escola de Ginebra. Aquesta proposta ha estat adaptada per tal d"intentar analitzar el nivell de desenvolupament cognitiu dels infants no només a partir del que aquests són capaços de comprendre per sí sols sinó també a través d"ajudes, les quals han estat escollides, administrades i valorades pels propis estudiants. En aquesta revisió de la pràctica, s"han volgut delimitar les diferents estratègies utilitzades pels estudiants per tal de promoure la comprensió de la conservació en els infants, fet que ha permès la reflexió sobre d"altres possibles formes d"ensenyar i ensenyar a ensenyar aquest concep