948 research outputs found

    Demografía y mercado de trabajo en la provincia de Cádiz: algunas reflexiones

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    El artículo se centra en un análisis del mercado de trabajo en la provincia de Cádiz, un mercado con la tasa de desempleo más alta en España. En este artículo, los principales factores han sido identificados. El punto de partida para el análisis es la evaluación de las variables demográficas, siendo el punto central el análisis de las variables socio-económicas. Se ha estudiado la dinámica sectorial y la cualificación de los trabajadores, siendo uno de los factores principales que pueden explicar la especial situación del mercado de trabajo de Cádiz. Una característica de Cádiz es la juventud de su población que puede ser un factor para la migración. Hay múltiples factores que son cruciales en el contexto del mercado de trabajo de Cádiz. Estos son la crisis de los astilleros, la menor cualificación de los trabajadores, la localización en la periferia de España y la débil generación de empleo en el sector servicios. Finalmente presentamos las principales conclusiones.The paper focuses on an empirical analysis of the labour market in the province of Cadiz, a market with the highest unemployment rate in Spain. In this article, the main causal factors of the situation have been identified. The starting point for the analysis is the evaluation of the demographic variables with the focal point being an analysis of socio-economic variables. The sectorial dynamic and the skills of workers have been studied, being primary factors which can explain the special situation in the labour market of Cadiz. A feature of Cadiz is a young population which could be a primary motivating factor in migration. A number of essential factors are crucial in the context of the labour market. These are the shipyards crisis, the lower skills of workers, location at the Spanish geographic periphery and the weak generation of employment in the service sector. Finally, we present the main conclusions.Domínguez Jurado, J.M. y Pérez González, M. del C. (2004). Demografía y mercado de trabajo en la provincia de Cádiz: algunas reflexiones. Revista de estudios andaluces, 25, 77-94

    Our ten years of work on transparet box business simulation

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    Traditional business games are of the so-called black-box type (BBBS=Black box business simulator); that is to say, the internal structure which generates the results of the simulation after decision-making is not known. As a result, the player normally operates by trial and error and bases his decisions on the symptoms of the problem (the observed behaviors of the system's variables) and not on the real causes of the problem (the system's structure). Since 1988 José A.D. Machuca has insisted that the business games based on System Dynamics models should be Transparent-box business simulators (TBBSs). That means that, during the game, the user has access to the structure of the underlying model and is able to relate it to the observed behaviors. The hypothesis is that such transparency would facilitate causal reflection and favor systemic learning of business problems. In 1990, the G.I.D.E.A.O. Research Group took action on this idea and centered one of its lines of research on this matter, with three main objectives: a) Creation of TBBSs, b) Introduction of TBBSs in undergraduate and graduate Management courses as well as in executive training, c) Experimentation in controlled environments in order to test the hypothesis mentioned in the above paragraph. Now, ten years after the birth of the idea, we would like to share in this paper the results obtained during that period

    New Trends in the Control of Grid-Connected Photovoltaic Systems for the Provision of Ancillary Services

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    Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).The gradual displacement of conventional generation from the energy mix to give way to renewable energy sources represents a paradigm shift in the operation of future power systems: on the one hand, renewable technologies are, in general, volatile and difficult to predict; and on the other hand, they are usually connected to the grid through electronic power converters. This decoupling due to power converters means that renewable generators lack the natural response that conventional generation has to the imbalances between demand and generation that occur during the regular operation of power systems. Renewable generators must, therefore, provide a series of complementary services for the correct operation of power systems in addition to producing the necessary amount of energy. This paper presents an overview of existing methods in the literature that allow photovoltaic generators to participate in the provision of ancillary services, focusing on solutions based on power curtailment by modifying the traditional maximum power point tracking algorithm

    Thermodynamic optimization subsumed in stability phenomena

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    [EN]In the present paper the possibility of an energetic self-optimization as a consequence of thermodynamic stability is addressed. This feature is analyzed in a low dissipation refrigerator working in an optimized trade-off regime (the so-called Omega function). The relaxation after a perturbation around the stable point indicates that stability is linked to trajectories in which the thermodynamic performance is improved. Furthermore, a limited control over the system is analyzed through consecutive external random perturbations. The statistics over many cycles corroborates the preference for a better thermodynamic performance. Endoreversible and irreversible behaviors play a relevant role in the relaxation trajectories (as well as in the statistical performance of many cycles experiencing random perturbations). A multi-objective optimization reveals that the well-known endoreversible limit works as an attractor of the system evolution coinciding with the Pareto front, which represents the best energetic compromise among efficiency, entropy generation, cooling power, input power and the Omega function. Meanwhile, near the stable state, performance and stability are dominated by an irreversible behavior

    A Delphi study to recognize and assess systems of systems vulnerabilities

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    Context: System of Systems (SoS) is an emerging paradigm by which independent systems collaborate by sharing resources and processes to achieve objectives that they could not achieve on their own. In this context, a number of emergent behaviors may arise that can undermine the security of the constituent systems. Objective: We apply the Delphi method with the aims to improve our understanding of SoS security and related problems, and to investigate their possible causes and remedies. Method: Experts on SoS expressed their opinions and reached consensus in a series of rounds by following a structured questionnaire. Results: The results show that the experts found more consensus in disagreement than in agreement about some SoS characteristics, and on how SoS vulnerabilities could be identified and prevented. Conclusions: From this study we learn that more work is needed to reach a shared understanding of SoS vul nerabilities, and we leverage expert feedback to outline some future research directions.Ministerio de Ciencia, Innovación y Universidades PID2019-105455GB-C3

    Digital persona portrayal: Identifying pluridentity vulnerabilities in digital life

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    The increasing use of the Internet for social purposes enriches the data available online about all of us and promotes the concept of the Digital Persona. Actually, most of us are represented online by more than one identity, what we define here as a Pluridentity . This trend brings increased risks: it is well known that the security of a Digital Persona can be exploited if its data and security are not effectively managed. In this paper, we focus specifically on a new type of digital attack that can be perpetrated by combining pieces of data belonging to one same Pluridentity in order to profile their target. Some victims can be so accurately depicted when looking at their Pluridentity that by using the gathered information attackers can execute very personalized social engineering attacks, or even bypass otherwise safe security mecha- nisms. We characterize these Pluridentity attacks as a security issue of a virtual System of Systems, whose constituent systems are the individual identities and the humans themselves. We present a strategy to identify vulnerabilities caused by overexposure due to the combination of data from the constituent iden- tities of a Pluridentity. To this end we introduce the Digital Persona Portrayal Metamodel, and the related Digital Pluridentity Persona Portrayal Analysis process that supports the architecting of data from differ- ent identities: such model and process can be used to identify the vulnerabilities of a Pluridentity due to its exploitation as a System of Systems. The approach has been validated on the Pluridentities of seven- teen candidates selected from a data leak, by retrieving the data of their Digital Personae, and matching them against the security mechanisms of their Pluridentities. After analyzing the results for some of the analyzed subjects we could detect several vulnerabilities.Ministerio dell'Universitá e della Ricerca (Italia) GAUSS 2015KWREMXMinisterio de Economía y Competitividad TIN2016-76956-C3-2-R (POLOLAS

    Security Assessment of Systems of Systems

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    Engineering Systems of Systems is one of the new chal-lenges of the last few years. This depends on the increasing number of systems that must interact one with another to achieve a goal. One peculiarity of Systems of Systems is that they are made of systems able to live on their own with well-established functionalities and requirements, and that are not necessarily aware of the joint mission or prepared to collaborate. In this emergent scenario, securi-ty is one crucial aspect that must be considered from the very beginning. In fact, the security of a System of Sys-tems is not automatically granted even if the security of each constituent system is guaranteed. The aim of this paper is to address the problem of assessing security properties in Systems of Systems. We discuss the specific security aspects of such emergent systems, and propose the TeSSoS approach, which includes modelling and testing security properties in Systems of Systems and introduces the Red and Blue Requirements Specification concepts.Ministerio dell'Universitá e della Ricerca (Italia) GAUSS 2015KWREMXMinisterio de Economía y Competitividad TIN2016-76956-C3-2-R (POLOLAS

    Systematic Development of ERP Modules using a Model-Driven Strategy Focusing on the Users

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    ERP systems are composed of different functional modules on which each one addresses a different business area. Developments on these modules are managed independently on each one, which allow to handle and address the management of many related information requirements. In this context the startup G7Innovation works for its product iMEDEA. In this study we have combined two methodologies, Design Sprint and NDT 4.0; and systematized the development of ERP system modules. This combination allows you to use Design Sprint to generate and validate prototyping, and NDT 4.0 to do the study, analysis, and design of the software to be developed. In addition, according to the specifications defined in NDT, the code generation of the ERP module can be automated. This proposal has been validated in a case study in collaboration with the startup G7Innovation, where we have applied both methodologies on Odoo, an open source ERP system based in Python language. Thanks to the use of these two methodologies we have produced a module related to the needs of the clinic by reducing costs, times and human failures.Ministerio de Ciencia e Innovación TIN2016-76956-C3-2-

    Electrochromic polyoxometalate material as a sensor of bacterial activity

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    L. fermentum, a bacterium of human microbiota, acts as an electron donor to the electrochromic [P2MoVI18O62]6. Since, the reductive capacity of L. fermentum correlates with its metabolic activity, the reaction with [P2MoVI18O62]6- affords a means of evaluating its activity. Following this logic, we have concluded that vancomycin severely affects the activity of L. fermentum whereas omeprazole does not.FQM368 Bionanopartículas Metálicas (BioNanomet)Departamento de Química InorgánicaThis work was funded by MINECO and FEDER (project CTQ2012-32236

    Meteorological patterns linked to landslide triggering in asturias (NW Spain): A preliminary analysis

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    Asturias is one of the most landslide prone areas in the north of Spain. Most landslides are linked to intense and continue rainfall events, especially between October and May. This fact points out precipitation as the main triggering factor in the study area. Thirteen rainfall episodes that caused 1064 landslides between 2008 and 2016 have been selected for its study. Landslide records come from the Principality of Asturias Landslide Database (BAPA) and meteorological data from the Spanish Meteorological Agency (AEMET). Meteorological conditions which took place during each period have been characterized by using NCEP/NCAR Reanalysis data. Four main landslide-triggering meteorological patterns have been identified for the Asturian territory: Strong Atlantic Anticyclone pattern (SAA), Atlantic Depression pattern (AD), Anticyclonic ridge pattern (AR) and Cut-off Low pattern (CL).This research is funded by the Department of Employment, Industry and Tourism of the Government of Asturias, Spain, and the European Regional Development Fund FEDER, within the framework of the research grant “GEOCANTABRICA: Procesos geológicos modeladores del relieve de la Cordillera Cantábrica” (FC-15-GRUPIN14-044), and supported on the cooperation between the Department of Geology at the University of Oviedo and the AEMET
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