Search results for "ERT"
showing 10 items of 21537 documents
A Hybrid Control Strategy for Quadratic Boost Converters with Inductor Currents Estimation
2020
International audience; This paper deals with a control strategy for a DC-DC quadratic boost converter. In particular, a hybrid control scheme is proposed to encompass a control law and an observer for the estimation of the system states, based only on the measurements of the input and output voltages. Differently from classical control methods, where the controller is designed from a small-signal model, here the real model of the system is examined without considering the average values of the discrete variables. Using hybrid dynamical system theory, asymptotic stability of a neighborhood of the equilibrium point is established, ensuring practical stability of the origin, which contains es…
Las huellas de la interdisciplinariedad en la trayectoria de Enric Mestre. ?Intercambios e investigaciones cruzadas entre las esculturas cerámicas y …
2020
La destacada actividad artística de Enric Mestre (Alboraya / Valencia, 1936) solo pude abordarse, en su compleja diversidad y riqueza, si se mantiene, como eje metodológico básico de su estudio crítico, el abierto enfoque de su sistemática interdisciplinariedad. Los diálogos e intercambios entre la escultura cerámica, la arquitectura, la pintura, el dibujo y los murales conforman precisamente el ámbito plural de su constante quehacer artístico. Especialmente la investigación se centra en las esculturas cerámicas y en las pinturas geométricas, que constituyen los dos dilatados campos de su creación plástica, cultivados asiduamente, a lo largo del último medio siglo
Pricing Sovereign Contingent Convertible Debt
2016
We develop a pricing model for sovereign contingent convertible bonds (S-CoCo) with payment standstills triggered by a sovereign's credit default swap CDS spread. One innovation is the modeling of CDS spread regime switching which is prevalent during crises. Regime switching is modeled as a hidden Markov process and is integrated with a stochastic process of spread levels to obtain S-CoCo prices through simulation. The paper goes a step further and uses the pricing model in a Longstaff-Schwartz. American option pricing framework to compute state contingent S-CoCo prices at some risk horizon, thus facilitating risk management. Dual trigger pricing is also discussed using the idiosyncratic CD…
Model Co-creation from a Modeler’s Perspective: Lessons Learned from the Collaboration Between Ethnographers and Modelers
2018
This paper reports on the authors’ ongoing collaboration on model co-creation, a process that involves not only the reconciliation of methodologies (qualitative vs. quantitative), but also of epistemologies (empirical vs empirical/rationalist) and ontologies (observable referent vs. abstracted referent). The co-creation process has taken place over several months, from early 2017, both in person, teleconferencing and via email. The result was an ethnographic model of the refugee situation in Lesbos, Greece. The qualifier “ethnographic” means that the simulation’s purpose was to capture the problem situation described by ethnographers in a manner that resembles their observations, not to ans…
Combined column-and-row-generation for the optimal communication spanning tree problem
2018
Abstract This paper considers the exact solution of the optimal communication spanning tree problem (OCSTP), which can be described as follows: Given an undirected graph with transportation costs on every edge and communication requirements for all pairs of vertices, the OCSTP seeks for a spanning tree that minimizes the sum of the communication costs between all pairs of vertices, where the communication cost of a pair of vertices is defined as their communication requirement multiplied by the transportation cost of the unique tree path that connects the two vertices. Two types of compact formulations for OCSTP were presented in the literature. The first one is a four-index model based on …
Heuristics for the min–max arc crossing problem in graphs
2018
Abstract In this paper, we study the visualization of complex structures in the context of automatic graph drawing. Constructing geometric representations of combinatorial structures, such as networks or graphs, is a difficult task that requires an expert system. The automatic generation of drawings of graphs finds many applications from software engineering to social media. The objective of graph drawing expert systems is to generate layouts that are easy to read and understand. This main objective is achieved by solving several optimization problems. In this paper we focus on the most important one: reducing the number of arc crossings in the graph. This hard optimization problem has been…
Analyzing Cascading Effects in Interdependent Critical Infrastructures
2018
International audience; Critical Infrastructures (CIs) are resources that are essential for the performance of society, including its economy and its security. Large-scale disasters, whether natural or man-made, can have devastating primary (direct) effects on some CI and significant indirect effects (cascading effects) on other CIs, because CIs are interconnected and depend on each other’s services. Recent work by Laugé et al. expressed the dependency values among CIs as dependency matrices for various durations of the primary CI failure. For better preparedness and mitigation of CI failures knowledge of the weak points in CI interdependencies is crucial. To this effect, we have developed …
Visualization of Exchanged Information with Dynamic Networks: A Case Study of Fire Emergency Search and Rescue Operation
2017
To perform emergency response activities, complex networks of emergency responders from different emergency organizations work together to rescue affected people and to mitigate the property losses. However, to work efficiently, the emergency responders have to rely completely on the data which gets generated from heterogeneous data sources during search and rescue operation (SAR). From this abundant data, rescue teams share needed information which is hidden in the abundant data with one another to make decisions, obtain situational awareness and also to assign tasks. Moreover, understanding and analyzing the shared information is a complex and very challenging task. Therefore, in this pap…
Las normas ISO/IEC como mecanismos de responsabilidad proactiva en el Reglamento General de Protección de Datos
2021
El mercado de la certificación ha experimentado un auge sin precedentes tras la entrada en vigor y ulterior aplicación del RGPD. Ello obliga a poner de relieve la relevancia de estos mecanismos como elementos claves en la prevención de potenciales violaciones de la seguridad de los datos personales. En el presente trabajo examinamos cómo la naturaleza técnica de estos instrumentos ha cedido hacia su corregulación a los efectos de garantizar una adaptación efi ciente a los continuos cambios de una gran tipología de productos, servicios o sistemas. Pretende proporcionarse una panorámica holística sobre la práctica totalidad de estándares que afectan a las dimensiones de privacidad y protecció…
Sustainable growth and environmental catastrophes
2017
Abstract In the standard AK growth model we introduce the threat of an ecological catastrophe and study the consequences for the economic variables in the long-run. We extend the basic framework by considering two environmental externalities: the first one is local and gives account of the marginal damage from emissions flow; the second one is aggregate, or global, and relates to the extreme damage which may happen if the accumulated stock of pollutants is on the threshold of a worldwide catastrophe. In this context dominated by market failures, we focus on the socially optimal solution and the search of conditions for sustainability. We identify the efficient balanced growth path, which ma…