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EDF and the Brazilian Power Sector

Masvigner, Raphael Charlie Jean
Fonte: Fundação Getúlio Vargas Publicador: Fundação Getúlio Vargas
Tipo: Dissertação
Português
Relevância na Pesquisa
37.88%
Electricité de France (EDF) is a leading player in the European energy market by being both the first electricity producer in Europe and the world’s leading nuclear plant operator. EDF is also the first electricity producer and supplier in France. However, Europe, EDF’s core market, is currently underperforming: the European sovereign debt crisis is lowering significantly the growth perspective of an energy market that has already reached its maturity. As a consequence, European energy companies are now looking at international markets and especially BRIC economies where economic growth potential remains high. Among them, Brazil is expected to keep its strong economic and electricity demand growth perspectives for the coming decades. Though Brazil has not been considered as a strategic priority for EDF after the Light reversal in 2006, the current economic situation has led the Group to reconsider its position toward the country. EDF’s current presence in Brazil is limited to its stake in UTE Norte Fluminense, a thermal plant, located in the state of Rio de Janeiro. This report investigates the possibility and the feasibility of EDF’s activities expansion in Brazil and what added value it could bring for the Brazilian power market. Considering that the status quo would not allow EDF to take full advantage of Brazil’s future growth...

Parametric VaR with goodness-of-fit tests based on EDF statistics for extreme returns

Moralles, Herick Fernando; Rebelatto, Daisy Aparecida do Nascimento; Sartoris, Alexandre
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1648-1658
Português
Relevância na Pesquisa
27.01%
Parametric VaR (Value-at-Risk) is widely used due to its simplicity and easy calculation. However, the normality assumption, often used in the estimation of the parametric VaR, does not provide satisfactory estimates for risk exposure. Therefore, this study suggests a method for computing the parametric VaR based on goodness-of-fit tests using the empirical distribution function (EDF) for extreme returns, and compares the feasibility of this method for the banking sector in an emerging market and in a developed one. The paper also discusses possible theoretical contributions in related fields like enterprise risk management (ERM). © 2013 Elsevier Ltd.

Specifying and information system for managing distributed generation equipment and related services : a case study with EDF energy in the UK

Reina, André Moreira
Fonte: Universidade do Porto Publicador: Universidade do Porto
Tipo: Dissertação Formato: VIII, 43 f., 30 cm; application/pdf
Português
Relevância na Pesquisa
27.01%
Estágio realizado na EDF Energy Networks; Tese de mestrado integrado. Engenharia Informática e Computação. Faculdade de Engenharia. Universidade do Porto. 2009

What drives corporate default risk premia? Evidence from the CDS market

Díaz, A.; Groba, J.; Serrano, P.
Fonte: Instituto Politécnico de Lisboa Publicador: Instituto Politécnico de Lisboa
Tipo: Conferência ou Objeto de Conferência
Publicado em /04/2011 Português
Relevância na Pesquisa
27.01%
This paper studies the evolution of the default risk premia for European firms during the years surrounding the recent credit crisis. We employ the information embedded in Credit Default Swaps (CDS) and Moody’s KMV EDF default probabilities to analyze the common factors driving this risk premia. The risk premium is characterized in several directions: Firstly, we perform a panel data analysis to capture the relationship between CDS spreads and actual default probabilities. Secondly, we employ the intensity framework of Jarrow et al. (2005) in order to measure the theoretical effect of risk premium on expected bond returns. Thirdly, we carry out a dynamic panel data to identify the macroeconomic sources of risk premium. Finally, a vector autoregressive model analyzes which proportion of the co-movement is attributable to financial or macro variables. Our estimations report coefficients for risk premium substantially higher than previously referred for US firms and a time varying behavior. A dominant factor explains around 60% of the common movements in risk premia. Additionally, empirical evidence suggests a public-to-private risk transfer between the sovereign CDS spreads and corporate risk premia.

The Communication Factor EDF and the Toxin–Antitoxin Module mazEF Determine the Mode of Action of Antibiotics

Kolodkin-Gal, Ilana; Sat, Boaz; Keshet, Alex; Kulka, Hanna Engelberg-
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.01%
It was recently reported that the production of Reactive Oxygen Species (ROS) is a common mechanism of cell death induced by bactericidal antibiotics. Here we show that triggering the Escherichia coli chromosomal toxin–antitoxin system mazEF is an additional determinant in the mode of action of some antibiotics. We treated E. coli cultures by antibiotics belonging to one of two groups: (i) Inhibitors of transcription and/or translation, and (ii) DNA damaging. We found that antibiotics of both groups caused: (i) mazEF-mediated cell death, and (ii) the production of ROS through MazF action. However, only antibiotics of the first group caused mazEF-mediated cell death that is ROS-dependent, whereas those of the second group caused mazEF-mediated cell death by an ROS-independent pathway. Furthermore, our results showed that the mode of action of antibiotics was determined by the ability of E. coli cells to communicate through the signaling molecule Extracellular Death Factor (EDF) participating in mazEF induction.

A Summary of the New International EAACI/GA2LEN/EDF/WAO Guidelines in Urticaria

Zuberbier, Torsten
Fonte: World Allergy Organization Journal Publicador: World Allergy Organization Journal
Tipo: Artigo de Revista Científica
Publicado em 13/01/2012 Português
Relevância na Pesquisa
27.01%
Urticaria is a heterogeneous group of disorders, especially acute urticaria and angiooedema can be a medical emergency. This paper summarizes the EAACI/GA2LEN/EDF/WAO guidelines, the most recent international guidelines from 2009. Patients with urticaria are often not diagnosed and treated appropriately and the guidelines state that clinicians should always aim to provide complete symptom relief. The mainstay of urticaria treatment is the use of modern nonsedating antihistamines, if required up to 4-fold of standard doses.

The Quorum Sensing Peptides PhrG, CSP and EDF Promote Angiogenesis and Invasion of Breast Cancer Cells In Vitro

De Spiegeleer, Bart; Verbeke, Frederick; D’Hondt, Matthias; Hendrix, An; Van De Wiele, Christophe; Burvenich, Christian; Peremans, Kathelijne; De Wever, Olivier; Bracke, Marc; Wynendaele, Evelien
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 17/03/2015 Português
Relevância na Pesquisa
27.01%
The role of the human microbiome on cancer progression remains unclear. Therefore, in this study, we investigated the influence of some quorum sensing peptides, produced by diverse commensal or pathogenic bacteria, on breast cancer cell invasion and thus cancer outcome. Based on microscopy, transcriptome and Chick Chorioallantoic Membrane (CAM) analyses, four peptides (PhrG from B. subtilis, CSP from S. mitis and EDF from E. coli, together with its tripeptide analogue) were found to promote tumour cell invasion and angiogenesis, thereby potentially influencing tumour metastasis. Our results offer not only new insights on the possible role of the microbiome, but also further opportunities in cancer prevention and therapy by competing with these endogenous molecules and/or by modifying people’s life style.

The extracellular death factor (EDF) protects Escherichia coli by scavenging hydroxyl radicals induced by bactericidal antibiotics

Yan, Zhongyi; Li, Guodong; Gao, Yanfeng; Zhai, Wenjie; Qi, Yuanming; Zhai, Mingxia
Fonte: Springer International Publishing Publicador: Springer International Publishing
Tipo: Artigo de Revista Científica
Publicado em 16/04/2015 Português
Relevância na Pesquisa
27.8%
The newly discovered extracellular death factor (EDF) is a pentapeptide with the sequence NNWNN in Escherichia coli. It was reported that it participated in the cell death process mediated by toxin-antitoxin system mazEF. Reactive oxygen species (ROS) are recently considered as common factors for bactericidal antibiotics-mediated cell death. Previous study indicated that EDF could scavenge hydroxyl radicals and might act as a signal molecule with dual effects, “death” and “survival”. But the structure-activity relationship of EDF and the effects of EDF on the activity of antibiotics remain unclear. In the present study, our results indicated that tryptophan could be the key residue to the hydroxyl radicals-scavenging activity of EDF, and EDF could protect Escherichia coli from killing by bactericidal antibiotics, but not by DNA-damaging or bacteriostatic antibiotics. Our results could provide novel evidence to understand the role of EDF in drug-resistance.

High Utilization Guarantee for Hierarchical Diff-EDF Schedulers

Saleh, Moutaz; University Kebangsaan Malaysia; Othman, Zulaiha Ali; University Kebangsaan Malaysia
Fonte: Editora da UFLA Publicador: Editora da UFLA
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Peer-reviewed Article Formato: application/pdf
Publicado em 26/08/2015 Português
Relevância na Pesquisa
27.01%

Implementación del protocolo DFP en MaRTE OS y propuesta para su incorporación al lenguaje Ada

Gutiérrez López, Marina
Fonte: Universidade de Cantabria Publicador: Universidade de Cantabria
Tipo: Dissertação de Mestrado
Português
Relevância na Pesquisa
27.75%
RESUMEN:Las tareas en un sistema de tiempo real deben atenerse a unos requisitos temporales determinados. Para garantizar que estos requisitos se satisfacen se emplean técnicas de planificación, como por ejemplo, la política de planificación dinámica EDF. En un sistema EDF las tareas se ejecutan en orden de plazo absoluto creciente. Además en cualquier sistema realista hay recursos compartidos entre las tareas. El acceso a estos recursos debe estar controlado para que no se produzcan accesos concurrentes a los mismos que puedan derivar en un funcionamiento erróneo del sistema. Existen diversos protocolos para proteger el acceso a recursos compartidos. Para sistemas EDF el más utilizado es el SRP. El protocolo SRP introduce el concepto de nivel de expulsión en las tareas y recursos del sistema. Su uso requiere modificar las reglas de la planificación EDF, de forma que para establecer el orden de ejecución de las tareas debe tenerse en cuenta tanto el plazo absoluto de las tareas como su nivel de expulsión. El DFP es un nuevo protocolo de sincronización de acceso a recursos compartidos en sistemas de planificación dinámica EDF que ha sido propuesto recientemente como alternativa al protocolo SRP. Se basa en la idea del suelo de plazo...

On the Convergence of the Holistic Analysis for EDF Distributed Systems

Díaz de Cerio Urain, Unai; Uribe, Juan P.; González Harbour, Michael; Palencia Gutiérrez, José Carlos
Fonte: Universidade de Cantabria Publicador: Universidade de Cantabria
Tipo: info:eu-repo/semantics/workingPaper; submittedVersion
Português
Relevância na Pesquisa
37.69%
Dynamic scheduling techniques, and EDF (Earliest Deadline First) in particular, have demonstrated their ability to increase the schedulability of real time systems compared to fixed-priority scheduling. In distributed systems, the scheduling policies of the processing nodes tend to be the same as in stand-alone systems and, although few EDF networks exist, it is foreseen that dynamic scheduling will gradually develop into real-time networks. There are some response time analysis techniques for EDF scheduled distributed systems, mostly derived from the holistic analysis developed by Spuri. The convergence of the holistic analysis in context of EDF distributed systems with shared resources had not been studied until now. There is a circular dependency between tasks’ release jitter values, response times and preemption level ceilings of shared resources. In this paper we present an extension of Spuri’s algorithm and we demonstrate that its iterative formulas are non-decreasing, even in the presence of shared resources. This result enables us to assert that the new algorithm converges towards a solution for the response times of the tasks and messages in a distributed system.

Análisis de planificabilidad basado en offsets en sistemas distribuidos de tiempo real con prioridades dinámicas

Díaz de Cerio Urain, Unai
Fonte: Universidade de Cantabria Publicador: Universidade de Cantabria
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
27.93%
RESUMEN: La tesis doctoral está dedicada al análisis de planificabilidad en sistemas de tiempo real. Este análisis se realiza mediante técnicas de cálculo de tiempo de respuesta de peor caso. El trabajo está centrado en sistemas multiprocesador o distribuidos gobernados por eventos. El objetivo principal de la tesis es potenciar el uso de planificadores por prioridades dinámicas, concretamente planificadores EDF (Earliest Deadline First, Plazo más Cercano Primero). Habiéndose demostrado que la planificación EDF permite alcanzar cotas de utilización superiores a las de las técnicas de prioridades fijas en sistemas monoprocesador, el estudio y desarrollo de técnicas de análisis en sistemas distribuidos o multiprocesador es claramente inferior a los de la planificación por prioridades fijas. Para este tipo de sistemas las técnicas de análisis exactas son muy costosas y, por ello, las técnicas de análisis usuales son aproximadas. En esta tesis, se pretende mejorar las técnicas de análisis para planificación EDF reduciendo así el pesimismo de las técnicas actuales. Para conseguir este objetivo, en primer lugar se valida el método utilizado previamente y, posteriormente, se aplican mejoras sobre este para reducir el pesimismo del cálculo. Estas mejoras se obtienen adaptando métodos desarrollados para prioridades fijas a sistemas EDF. En concreto...

Estudio de la planificabilidad y optimización de sistemas distribuidos de tiempo real basados en prioridades fijas y EDF

Rivas Concepción, Juan María
Fonte: Universidade de Cantabria Publicador: Universidade de Cantabria
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
37.48%
RESUMEN: El trabajo llevado a cabo en esta tesis se centra en realizar un estudio en profundidad de las soluciones que producen las técnicas de análisis de planificabilidad y asignación de parámetros de planificación para sistemas distribuidos, como consecuencia del cual se obtienen una serie de resultados que pueden guiar al diseñador a identificar qué algoritmo de planificación o técnica debe aplicar a su problema. También se adaptan las técnicas de análisis y optimización existentes a su aplicación a un conjunto más amplio de sistemas, que permiten la mezcla de diferentes planificadores en los recursos procesadores del sistema distribuido, y se proponen nuevas técnicas de asignación de plazos locales de planificación para EDF.; ABSTRACT: The work carried out in this thesis focuses on performing an exhaustive study of the solutions produced by both the schedulability analysis techniques, and the scheduling parameters assignment techniques, for distributed systems. The results obtained in this study can help a real-time system designer to identify the algorithm or scheduling policy to be applied. Additionally, the current analysis and optimization techniques are adapted for their application to a wider range of systems...

Supporting intra-task parallelism in real-time multiprocessor systems

Fonseca, José
Fonte: Instituto Politécnico do Porto. Instituto Superior de Engenharia do Porto Publicador: Instituto Politécnico do Porto. Instituto Superior de Engenharia do Porto
Tipo: Dissertação de Mestrado
Publicado em //2012 Português
Relevância na Pesquisa
27.3%
Os sistemas de tempo real modernos geram, cada vez mais, cargas computacionais pesadas e dinâmicas, começando-se a tornar pouco expectável que sejam implementados em sistemas uniprocessador. Na verdade, a mudança de sistemas com um único processador para sistemas multi- processador pode ser vista, tanto no domínio geral, como no de sistemas embebidos, como uma forma eficiente, em termos energéticos, de melhorar a performance das aplicações. Simultaneamente, a proliferação das plataformas multi-processador transformaram a programação paralela num tópico de elevado interesse, levando o paralelismo dinâmico a ganhar rapidamente popularidade como um modelo de programação. A ideia, por detrás deste modelo, é encorajar os programadores a exporem todas as oportunidades de paralelismo através da simples indicação de potenciais regiões paralelas dentro das aplicações. Todas estas anotações são encaradas pelo sistema unicamente como sugestões, podendo estas serem ignoradas e substituídas, por construtores sequenciais equivalentes, pela própria linguagem. Assim, o modo como a computação é na realidade subdividida, e mapeada nos vários processadores, é da responsabilidade do compilador e do sistema computacional subjacente. Ao retirar este fardo do programador...

Application of non-uniform laxity to EDF for aperiodic tasks to improve task utilisation on multicore platforms

Kumar, K Pradheep; Shanthi, A P
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/06/2009 Português
Relevância na Pesquisa
27.3%
This paper proposes a new scheduler applying the concept of non-uniform laxity to Earliest deadline first (EDF) approach for aperiodic tasks. This scheduler improves task utilisation (Execution time / deadline) and also increases the number of tasks that are being scheduled. Laxity is a measure of the spare time permitted for the task before it misses its deadline, and is computed using the expression (deadline - (current time + execution time)). Weight decides the priority of the task and is defined by the expression (quantum slice time / allocated time)*total core time for the task. Quantum slice time is the time actually used, allocated time is the time allocated by the scheduler, and total core time is the time actually reserved by the core for execution of one quantum of the task. Non-uniform laxity enables scheduling of tasks that have higher priority before the normal execution of other tasks and is computed by multiplying the weight of the task with its laxity. The algorithm presented in the paper has been simulated on Cheddar, a real time scheduling tool and also on SESC, an architectural simulator for multicore platforms, for upto 5000 random task sets, and upto 5000 cores. This scheduler improves task utilisation by 35% and the number of tasks being scheduled by 36%...

Efficient Feasibility Analysis for Real-Time Systems with EDF Scheduling

Albers, Karsten; Slomka, Frank
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 25/10/2007 Português
Relevância na Pesquisa
27.3%
This paper presents new fast exact feasibility tests for uniprocessor real-time systems using preemptive EDF scheduling. Task sets which are accepted by previously described sufficient tests will be evaluated in nearly the same time as with the old tests by the new algorithms. Many task sets are not accepted by the earlier tests despite them beeing feasible. These task sets will be evaluated by the new algorithms a lot faster than with known exact feasibility tests. Therefore it is possible to use them for many applications for which only sufficient test are suitable. Additionally this paper shows that the best previous known sufficient test, the best known feasibility bound and the best known approximation algorithm can be derived from these new tests. In result this leads to an integrated schedulability theory for EDF.; Comment: Submitted on behalf of EDAA (http://www.edaa.com/)

A Heuristic EDF Uplink Scheduler for Real Time Application in WiMAX Communication

Lal, Nidhi; Singh, Anurag Prakash; Kumar, Shishupal; Mittal, Shikha; Singh, Meenakshi
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.69%
WiMAX, Worldwide Interoperability for Microwave Access, is a developing wireless communication scheme that can provide broadband access to large-scale coverage. WiMAX belongs to the family of standards of IEEE-802.16. To satisfy user demands and support a new set of real time services and applications, a realistic and dynamic resource allocation algorithm is mandatory. One of the most efficient algorithm is EDF (earliest deadline first). But the problem is that when the difference between deadlines is large enough, then lower priority queues have to starve. So in this paper, we present a heuristic earliest deadline first (H-EDF) approach of the uplink scheduler of the WiMAX real time system. This H-EDF presents a way for efficient allocation of the bandwidth for uplink, so that bandwidth utilization is proper and appropriate fairness is provided to the system. We use Opnet simulator for implementing the WiMAX network, which uses this H-EDF scheduling algorithm. We will analysis the performance of the H-EDF algorithm in consideration with throughput as well as involvement of delay.

Heavy traffic analysis for EDF queues with reneging

Kruk, Łukasz; Lehoczky, John; Ramanan, Kavita; Shreve, Steven
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/04/2011 Português
Relevância na Pesquisa
27.48%
This paper presents a heavy-traffic analysis of the behavior of a single-server queue under an Earliest-Deadline-First (EDF) scheduling policy in which customers have deadlines and are served only until their deadlines elapse. The performance of the system is measured by the fraction of reneged work (the residual work lost due to elapsed deadlines) which is shown to be minimized by the EDF policy. The evolution of the lead time distribution of customers in queue is described by a measure-valued process. The heavy traffic limit of this (properly scaled) process is shown to be a deterministic function of the limit of the scaled workload process which, in turn, is identified to be a doubly reflected Brownian motion. This paper complements previous work by Doytchinov, Lehoczky and Shreve on the EDF discipline in which customers are served to completion even after their deadlines elapse. The fraction of reneged work in a heavily loaded system and the fraction of late work in the corresponding system without reneging are compared using explicit formulas based on the heavy traffic approximations. The formulas are validated by simulation results.; Comment: Published in at http://dx.doi.org/10.1214/10-AAP681 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org)

Ab initio-driven nuclear energy density functional method. A proposal for safe/correlated/improvable parametrizations of the off-diagonal EDF kernels

Duguet, T.; Bender, M.; Ebran, J. -P.; Lesinski, T.; Somà, V.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/02/2015 Português
Relevância na Pesquisa
27.48%
This programmatic paper lays down the possibility to reconcile the necessity to resum many-body correlations into the energy kernel with the fact that safe multi-reference energy density functional (EDF) calculations cannot be achieved whenever the Pauli principle is not strictly enforced, as is for example the case when many-body correlations are parametrized under the form of empirical density dependencies. Our proposal is to exploit a newly developed ab initio many-body formalism to guide the construction of safe, explicitly correlated and systematically improvable parametrizations of the {\it off-diagonal} energy and norm kernels that lie at the heart of the nuclear EDF method. The many-body formalism of interest relies on the concepts of symmetry breaking {\it and} restoration that have made the fortune of the nuclear EDF method and is, as such, amenable to this guidance. After elaborating on our proposal, we briefly outline the project we plan to execute in the years to come.; Comment: 14 pages, 5 figures

Elimination of EDF Rank at RIT

Waterstram-Rich, Kristen; Faculty Affairs Committee
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Final Paper
Português
Relevância na Pesquisa
37.3%
Elimination of EDF Rank (Approved by the Academic Senate May 20, 2010)