Encontrado(s) 2170865 resultado(s)
Encontrada(s) 217087 página(s)
Encontrada(s) 217087 página(s)
Algebraic and parametric solvers for the power flow problem: towards real-time and accuracy-guaranteed simulation of electric systems
- García-Blanco, Raquel
- Diez, Pedro
- Borzacchiello, Domenico
- Chinesta, Francisco
The power flow model performs the analysis of electric distribution and transmission systems. With this statement at hand, in this work we present a summary of those solvers for the power flow equations, in both algebraic and parametric version. The application of the Alternating Search Direction method to the power flow problem is also detailed. This results in a family of iterative solvers that combined with Proper Generalized Decomposition technique allows to solve the parametric version of the equations. Once the solution is computed using this strategy, analyzing the network state or solving optimization problems, with inclusion of generation in real-time, becomes a straightforward procedure since the parametric solution is available. Complementing this approach, an error strategy is implemented at each step of the iterative solver. Thus, error indicators are used as an stopping criteria controlling the accuracy of the approximation during the construction process. The application of these methods to the model IEEE 57-bus network is taken as a numerical illustration.
- García-Calderón, Carola
The regulation of advertising throughout the world ranges from almost total restriction, prohibitions on certain products, limitation of hours or use of some media, to extensive permissiveness with self-regulatory ethical codes or standards established by the publishers or advertisers themselves. This paper discusses advertising organizations in Mexico, and how they evolved from trying to be recognized to the constitution as pressure group with international alliances that are fighting against the promulgation of government regulations and looking for industry self-regulation.
Barcelona en Comú on Twitter. Analyzing the electoral communication of the confluence during the 2015 council election
- García-Carretero, Lucía
- Pérez-Altable, Laura
En los últimos años se ha producido un aumento del interés en las redes digitales como medio de comunicación política. Sin embargo su uso se encuentra determinado, entre otros factores, por la naturaleza y estrategias de cada partido político. Esta investigación analiza el uso que los partidos de la confluencia Barcelona en Comú llevaron a cabo durante la campaña de las municipales de 2015, del 8 al 22 de mayo, en la red digital Twitter. El método empleado ha sido el análisis de redes sociales de todos los tweets difundidos por los seis partidos políticos que forman la confluencia. Se profundiza en la relación comunicativa entre estos partidos, así como en la relación entre los partidos y los usuarios en la red digital analizando la bidireccionalidad del proceso comunicativo. El partido que generó más información electoral en Twitter durante la campaña fue Barcelona en Comú. AbstractIn recent years there has been a great deal of interest in digital networks as political communication tools. However, the use of social media depends on, among other things, the character of each political organization. The main objective of this research is to analyze Barcelona en Comú’s digital communication on Twitter during the municipal election campaign from May 8 to May 22, 2015 in Barcelona. The methodology is based on a social network analysis (SNA) of all the tweets disseminated by the six political parties that formed the confluence. The investigation deepens our understanding of the communicative relationship between the six parties, and between the parties and the users, with the aim of analyzing the bi-directionality of the communicative process. We conclude that the party that generated the most electoral information on Twitter during the electoral campaign was Barcelona en Comú.
- García-Carretero, Lucía
- Codina, Lluís
- Díaz-Noci, Javier
- Iglesias-García, Mar
Searching is one of the core activities in the digital world and therefore, it is one of the key elements in the analysis of digital media since part of their audiences and revenues comes from the so called search engine result page (SERP). In this paper we present some of the most used analyzing tools in search engine optimization (SEO) in order to consider their application in online media research studies. We apply the nine most important indicators of these tools to the home page of four Spanish general online media in order to assess its viability as alternative indicators to PageRank and other Google indicators
Film archives at the crossroads. Function and expansion of film archive activity in the new digital landscape
- García-Casado, Pablo
- Alberich-Pascual, Jordi
The intense digital change that is taking place in the world of cinema presents significant future challenges for film archives. This article reviews the extent to which the basis for the activities of film libraries founded in the 1930s remains valid in the information age, along with key debates questioning their identity and role in the 21st century. We explore the lines of film archives expansion that are being drawn in the current digital context, and finally offer a response to the crossroads that film libraries face today if they do not want to become isolated.
Rasch model of the GAIN substance problem scale among inpatient and outpatient clients in the city of São Paulo, Brazil
- Claro, Heloísa Garcia
- Oliveira, Márcia
- Fernandes, Ivan
- Titus, Janet
- Tarifa, Rosana Ribeiro
- Rojas, Thais Fernandes
- Hayasi Pinho, Paula
This study used the Rasch model to evaluate the psychometric properties of the Portuguese version of the Substance Problem Scale (SPS) of the “Global Appraisal of Individual Needs - Initial” for use in Brazil. The SPS measures alcohol and drug problem severity within a DSM-IV-TR framework. The goal of the Rasch analysis was to assess scale dimensionality, item severity, and differential item functioning (DIF). Data was collected from 40 inpatients and 70 outpatients in São Paulo, Brazil. The Rasch model fit and DIF by gender and level of care were examined. The SPS fit the Rasch model, with no items distorting the measure. Only three of the sixteen items performed differently between men and women and three performed differently by level of care. The results were compatible with those from Rasch analyses of the American English and Canadian English versions of the scale. The Portuguese version of the SPS is, thus, valid for use in Brazil, both with men and women in inpatient and outpatient programs.
Unequal scenarios of Europe in crisis. An approach to the effect of the socioeconomic crisis in European Welfare States. The case of Germany, Sweden and Spain
- Domingo, Marta
- Morales, Eva
The socio-economic and financial crisis, which is affecting Europe since 2008, is spreading its influence to all European Union member countries. However, as the welfare models are different, the consequences could also be different. Therefore, in this paper we try to make an assessment of this diversity with the following aims: to analyze the weakening of European Welfare States, using as models the Central European (represented by German, Spain and Sweden); and to make a comparison between these three countries, belonging to disparate socioeconomic models. For this we have used a methodological triangulation from the analysis of three elements: semi-structured in-depth interviews (29) to experts in the three contexts under study; Analysis of official data from secondary sources; documentary review of paper related to the topic. The results, which show disparities between countries, have been grouped into four categories: (1) the lack of effective social policies; (2) adaptation strategies; (3) prominent factors in the three contexts -focusing on employment/unemployment-; and (4) the protective ability -changes in the swedish system-.
- García-Espinosa, Julio
Scipedia (https://www.scipedia.com) is a comprehensive and unparalleled solution for the needs of open access / open data / open innovation / open science. Scipedia.com essentially integrates an advanced online publishing and data management platform within a collaborative social network. Scipedia offers free (and premium) publishing and data repository management services on the platform Scipedia.com and the possibility to build customized solutions for institutions (institutional open science portals). This presentation focuses on the application of Scipedia for the implementation of Science shops in the context of the R&D project Scishops.
- García-Espinosa, Julio
- Servan Camas, Borja
- Colom Cobb, Jonathan
- Oñate, Eugenio
Brash ice is the accumulation of floating ice made up of blocks no larger than two meters across. Navigation in brash ice is becoming more usual as new navigation routes are being opened in the Artic regions. This navigation brings new concerns regarding the interaction of ice blocks with the ship. This work presents recent advances towards the development of a computational model for simulation of this navigation condition including the interaction among the ship and the ice blocks. The computational tool developed in this work is based on the coupling of a Semi-Lagrangian Particle Finite Element Method (SL-PFEM) with a multi rigid-body dynamics tool. The Particle Finite Element Method (Idelsohn et al. 2004) is a versatile framework for the analysis of fluid-structure interaction problems. The PFEM combines Lagrangian particle-based techniques with the advantage of the integral formulation of the Finite Element Method (FEM). It has been shown (Idelsohn et al. 2014 and Nadukandi et al. 2017) to successfully simulate a wide variety of complex engineering problems, e.g. free-surface/multi-fluid flows with violent interface motions, multi-fluid mixing and buoyancy-driven segregation problems etc. The latest development within the framework of the PFEM is the X-IVAS (eXplicit Integration along the Velocity and Acceleration Streamlines) scheme. It is a semi-implicit scheme built over a Semi-Lagrangian (SL) formulation of the PFEM. In this work, the SL-PFEM model has been coupled with a multibody dynamics solver, able to handle the interactions between thousands of bodies, representing the different ice blocks. The interaction between the fluid flow and the ice blocks is taking into account by enriching the finite element space at the boundaries of the different blocks. This work is part of the research project NICESHIP sponsored by the U.S. Office of Naval Research under Grant N62909-16-1-2236.
- García-Espinosa, Julio
Scipedia (https://www.scipedia.com) is an innovative Open Science and Research Publishing Platform. Scipedia aims to connect researchers and professionals in science and technology and facilitate the sharing of knowledge, expertise and the outcome of their work. Scipedia.com was born to offer a complete solution for open science, and essentially integrates a collaborative social network for scientists with online editorial and document and data management tools. CIMNE has chosen Scipedia as the open publishing platform for its collections of monographs, articles and preprints, and technical and research reports (see https://www.scipedia.com/institution/cimne.upc.edu). The content of these collections will be compiled from the personal repositories in Scipedia of all CIMNE researchers. The objective of the workshop is to resolve the main doubts that may arise in the use of the platform, and specifically in the creation and management of document collections.