Search results for "Sistemas"
showing 10 items of 292 documents
Conceptual Characterization of Cybersecurity Ontologies
2020
Part 7:Risk and Security Modeling; International audience; Cybersecurity is known as the practice of protecting systems from digital attacks. Organizations are seeking efficient solutions for the management and protection of their assets. It is a complex issue, especially for great enterprises, because it requires an interdisciplinary approach. The kinds of problems enterprises must deal with and this domain complexity induces misinterpretations and misunderstandings about the concepts and relations in question. This article focus on dealing with Cybersecurity from an ontological perspective. The first contribution is a search of previously existing works that have defined Cybersecurity Ont…
Patient-specific simulation of the intrastromal ring segment implantation in corneas with keratoconus
2015
Purpose The purpose of this study was the simulation of the implantation of intrastromal corneal-ring segments for patients with keratoconus. The aim of the study was the prediction of the corneal curvature recovery after this intervention. Methods Seven patients with keratoconus diagnosed and treated by implantation of intrastromal corneal-ring segments were enrolled in the study. The 3D geometry of the cornea of each patient was obtained from its specific topography and a hyperelastic model was assumed to characterize its mechanical behavior. To simulate the intervention, the intrastromal corneal-ring segments were modeled and placed at the same location at which they were placed in the s…
The UWB-OFDM Channel Analysis in Frequency
2009
In this paper, the ultra-wideband channel with orthogonal frequency division multiplexing (UWB-OFDM) is analyzed in the frequency domain. For UWB-OFDM channels with log-normal fading in the time domain, we show that the amplitude of each subcarrier can be approximated by a Nakagami-m random variable, where the fading parameter, the mean power and the correlation coefficient are expressed in terms of the following parameters: time arrival of the clusters, inter-arrival time of rays inside clusters, and power decay constants of rays and clusters.
Generalized Conformal Symmetry and Extended Objects from the Free Particle
1998
The algebra of linear and quadratic functions of basic observables on the phase space of either the free particle or the harmonic oscillator possesses a finite-dimensional anomaly. The quantization of these systems outside the critical values of the anomaly leads to a new degree of freedom which shares its internal character with spin, but nevertheless features an infinite number of different states. Both are associated with the transformation properties of wave functions under the Weyl-symplectic group $WSp(6,\Re)$. The physical meaning of this new degree of freedom can be established, with a major scope, only by analysing the quantization of an infinite-dimensional algebra of diffeomorphi…
An empirical approach for evaluating the usability of model-driven tools
2013
MDD tools are very useful to draw conceptual models and to automate code generation. Even though this would bring many benefits, wide adoption of MDD tools is not yet a reality. Various research activities are being undertaken to find why and to provide the required solutions. However, insufficient research has been done on a key factor for the acceptance of MDD tools: usability. With the help of end-users, this paper presents a framework to evaluate the usability of MDD tools. The framework will be used as a basis for a family of experiments to get clear insights into the barriers to usability that prevent MDD tools from being widely adopted in industry. To illustrate the applicability of …
Diseño y aplicación de un Índice de Política Social : la utilización de la propuesta de UNRISD para comparar 3 países de la OCDE con distinto Estado …
2014
Hacia un Índice de Política Social: La Utilización de la propuesta de UNRISD para comparar 3 países de la OCDE con distinto Estado de Bienestar: Chile, España y Reino Unido. Doctorando: Gustavo Castillo Rozas Directores: Dr. Jorge Garcés - Dr. Francisco Ródenas En el año 2006, el Instituto de Investigación para el Desarrollo Social de Naciones Unidas –UNRISD para sus siglas en inglés- da a conocer un Índice de Política Social, que se encarga no de medir los resultados de las políticas, si no que de medir los esfuerzos de los gobiernos en materia de política social, es decir, no se fija en los outcomes (salidas o productos), si no que en los inputs (entradas). El SPI (siglas en inglés), es p…
Drogodependencias: de la epidemiología a la intervención. Estrategias y oportunidades
2005
El desarrollo en España del Plan Nacional sobre Drogas, ha supuesto la entrada en funcionamiento de diferentes fuentes de información epidemiológica en relación al uso de drogas y a los problemas relacionados con el uso de drogas. Desde 1987 se registra información sobre las admisiones a tratamiento, los episodios urgentes, y la mortalidad asociada al uso de drogas. Complementariamente, cada dos años se efectúa una encuesta domiciliaria dirigida a la población general y una encuesta escolar para evaluar el uso de drogas en la población general.
Nuevas herramientas y nuevas ideas para los responsables de recursos humanos. Validez estructural y predictiva del cuestionario de satisfacción ponde…
2013
One of the fundamental tasks for an Human Resource Management (HRM) practitioner consists in designing a reward system that can be broadly understood and can influence the attitudes and, subsequently, the behavior of individuals to permit achievement of organizational objectives. To do so, appropriate tools are necessary to allow key actions to be identified in terms of motivating employees; thereby, avoiding opportunistic costs derived from allocating resources needed to close the gap in employee satisfaction, with regard to non-priority factors for workers in satisfying their own personal needs. This article, thus, presents a dual assessment scale consisting of 44 items, categorized into …
Metabolic flux understanding of Pichia pastoris grown on heterogenous culture media
2014
[EN] Within the emergent field of Systems Biology, mathematical models obtained from physical chemical laws (the so-called first principles-based models) of microbial systems are employed to discern the principles that govern cellular behaviour and achieve a predictive understanding of cellular functions. The reliance on this biochemical knowledge has the drawback that some of the assumptions (specific kinetics of the reaction system, unknown dynamics and values of the model parameters) may not be valid for all the metabolic possible states of the network. In this uncertainty context, the combined use of fundamental knowledge and data measured in the fermentation that describe the behaviour…
La naturaleza de las cantidades presentes en el problema de probabilidad condicional: su influencia en el proceso de resolución del problema
2005
En la resolución de los problemas verbales de probabilidad condicional, los estudiantes están implicados en un proceso en el que podemos distinguir varias etapas o fases. Una de ellas es la traducción del texto del problema, generalmente escrito en la lengua vernácula, al lenguaje matemático. En las frases traducidas los estudiantes deben reconocer sucesos y probabilidades. Pero, en la mayoría de estos problemas los datos no están explícitamente mencionados en términos de probabilidad. En este caso, los estudiantes pueden resolver estos problemas recurriendo al pensamiento numérico y no necesariamente al probabilístico. En este trabajo investigamos, a través de un estudio con 51 estudiantes…