244 research outputs found
Period selection for minimal hyperperiod in periodic task systems
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component of this work in other works.Task period selection is often used to adjust the workload to the available computational resources. In this paper, we propose a model where each selected period is not restricted to be a natural number, but can be any rational number within a range. Under this generalization, we contribute a period selection algorithm that yields a much smaller hyperperiod than that of previous works: with respect to the largest period, the hyperperiod with integer constraints is exponentially bounded; with rational periods the worst case is only quadratic. By means of an integer approximation at each task activation, we show how our rational period approach can work under system clock granularity; it is thus compatible with scheduling analysis practice and implementation. Our finding has practical applications in several fields of real-time scheduling: lowering complexity in table driven schedulers, reducing search space in model checking analysis, generating synthetic workload for statistical analysis of real-time scheduling algorithms, etc.This work has been funded by the Spanish Government Research Office, project TIN2008-06766-C03-02 (RT-MODEL).Ripoll Ripoll, JI.; Ballester-Ripoll, R. (2013). Period selection for minimal hyperperiod in periodic task systems. IEEE Transactions on Computers. 62(9):1813-1822. https://doi.org/10.1109/TC.2012.243S1813182262
Analysis and compensation of scheduling delays in control systems
No full text[ES] Existe una separación entre la fase de diseño del regulador y su implementación en el computador de forma que, cada fase asume simplificaciones sobre la otra fase, lo cual lleva a un comportamiento inesperado o incorrecto del sistema a controlar. Desde hace algunos años, han surgido diversos trabajos que han apuntado la falta de integración de las dos fases de control. Esta línea de investigación se conoce como integración del control y la planificación. El estudio de los retardos que sufre un sistema de control es una parte importante de esta línea de investigación. El objetivo de este trabajo es presentar la revisión y análisis tanto de los retardos de un sistema de control, centrándonos en los retardos de control, como de las técnicas utilizadas para reducir estos retardos.[EN] There is a gap between control design phase and its real-time implementation in such a way that every phase assumes some simplifications on the other phase. This leads to a undesired behavior of the controlled system. In recent years some works have pointed out the need of integrating both phases. The goal of this work is to study the negative influence of delays in a control system, focusing in control delays and the techniques used to reduce it.Balbastre Betoret, P.; Lluesma, M.; Ripoll Ripoll, JI. (2010). Análisis y Compensación de los Retardos de Planificación en Sistemas de Control. Revista Iberoamericana de Automática e Informática industrial. 3(2):40-49. https://riunet.upv.es/handle/10251/146378OJS40493
El teatro grotesco de Laila Ripoll, autora
No full textEn el universo grotesco de las piezas de Laila Ripoll escogidas cohabitan las máscaras de Carnaval y los espectros y fantasmas, los vivos y los muertos, el mundo grotesquizado del presente y el mundo trágico del pasado, el mundo onírico de lo grotesco y la vida cotidiana en clave de sainete. Su originalidad está también en la manera en que la realidad trágica se nos da siempre a ver de manera indirecta: a través de la pantalla de los recuerdos, de los sueños, de las visiones, de simulacros, de rituales, de juegos metateatrales, de alegorías o de metáforas. Ripoll echa mano de todos los recursos teatrales de la grotesquización para pintarnos el mundo desolador de una humanidad «bestializada».In Laila Ripoll plays is outstanding the use of stylistic resources such us Carnival masks, spectres and ghosts, the living and the dead, the present grotesque world and the tragic world of the past, the world in which the live and death beings cohabit. The author points out the manner how «brutalized » humanity is shown through memories, dreams, visions, rituals, metatheatrical games and allegories
A taxonomy for threat actors' persistence techniques
No full text[EN] The main contribution of this paper is to provide an accurate taxonomy for Persistence techniques, which allows the detection of novel techniques and the identification of appropriate countermeasures. Persistence is a key tactic for advanced offensive cyber operations. The techniques that achieve persistence have been largely analyzed in particular environments, but there is no suitable platform¿agnostic model to structure persistence techniques. This lack causes a serious problem in the modeling of activities of advanced threat actors, hindering both their detection and the implementation of countermeasures against their activities. In this paper we analyze previous work in this field and propose a novel taxonomy for persistence techniques based on persistence points, a key concept we introduce in our work as the basis for the proposed taxonomy. Our work will help analysts to identify, classify and detect compromises, significantly reducing the amount of effort needed for these tasks. It follows a logical structure that can be easy to expand and adapt, and it can be directly used in commonly accepted industry standards such as MITRE ATT&CK.Villalón-Huerta, A.; Marco-Gisbert, H.; Ripoll-Ripoll, I. (2022). A taxonomy for threat actors' persistence techniques. Computers & Security. 121:1-14. https://doi.org/10.1016/j.cose.2022.102855S11412
CNA Tactics and Techniques: A Structure Proposal
No full text[EN] Destructive and control operations are today a major threat for cyber physical systems. These operations, known as Computer Network Attack (CNA), and usually linked to state-sponsored actors, are much less analyzed than Computer Network Exploitation activities (CNE), those related to intelligence gathering. While in CNE operations the main tactics and techniques are defined and well structured, in CNA there is a lack of such consensuated approaches. This situation hinders the modeling of threat actors, which prevents an accurate definition of control to identify and to neutralize malicious activities. In this paper, we propose the first global approach for CNA operations that can be used to map real-world activities. The proposal significantly reduces the amount of effort need to identify, analyze, and neutralize advanced threat actors targeting cyber physical systems. It follows a logical structure that can be easy to expand and adapt.Villalón-Huerta, A.; Ripoll-Ripoll, I.; Marco-Gisbert, H. (2021). CNA Tactics and Techniques: A Structure Proposal. Journal of Sensor and Actuator Networks. 10(1):1-23. https://doi.org/10.3390/jsan10010014S12310
SOC Critical Path: A defensive Kill Chain model
No full text[EN] Different kill chain models have been defined and analyzed to provide a common sequence of actions followed in offensive cyber operations. These models allow analysts to identify these operations and to understand how they are executed. However, there is a lack of an equivalent model from a defensive point of view: this is, there is no common sequence of actions for the detection of threats and their accurate response. This lack causes not only problems such as unstructured approaches and conceptual errors but, what is most important, inefficiency in the detection and response to threats, as defensive tactics are not well identified. For this reason, in this work we present a defensive kill chain approach where tactics for teams in charge of cyber defense activities are structured and arranged. We introduce the concept of SOC Critical Path (SCP), a novel kill chain model to detect and neutralize threats. SCP is a technology¿independent model that provides an arrangement of mandatory steps, in the form of tactics, to be executed by Computer Network Defense teams to detect hostile cyber operations. By adopting this novel model, these teams increase the performance and the effectiveness of their capabilities through a common framework that formalizes the steps to follow for the detection and neutralization of threats. In this way, our work can be used not only to identify detection and response gaps, but also to implement a continuous improvement cycle over time.Villalón-Huerta, A.; Marco-Gisbert, H.; Ripoll-Ripoll, I. (2022). SOC Critical Path: A defensive Kill Chain model. IEEE Access. 10:13570-13581. https://doi.org/10.1109/ACCESS.2022.3145029S13570135811
Ovidio en el Cancionero de Ripoll
No full textEste trabajo se centra en el Cancionero de Ripoll, una colección de veinte poemas latinos de
lírica amorosa compuestos en el siglo XII. Su objetivo es examinar la influencia de Ovidio, el
autor más popular de esta época, en dicha obra. Concretamente se comentan una por una las
analogías con Ovido que han apuntado estudiosos anteriores en una selección de trece de sus
poemas, los que contienen más similitudes (nº 1-11, 19-20). Además, se incluye una
traducción personal de tales poemas al castellano, así como de las analogías de Ovidio, y una
introducción al Cancionero en la que se trata el contexto histórico, el manuscrito que lo
conserva, el género literario y estructura de la obra, las influencias recibidas y los problemas
que plantea en cuanto a su autoría, fecha y lugar de composición.This work focuses on the Cancionero de Ripoll, a collection of twenty Latin love poems
composed in the 12th century. Its aim is to examine the influence of Ovid, the most popular
author of this period, on this anthology. Specifically, it analyses one by one the analogies with
Ovid noted by previous scholars in a selection of thirteen poems, those containing the most
similarities (nos. 1-11, 19-20). In addition, it includes a personal translation of these poems
into Spanish, as well as of Ovid's analogies, and an introduction to the Cancionero in which
the historical context, the manuscript that preserves it, the literary genre and structure of the
work, the influences it assimilated and the problems it raises regarding its authorship, date
and place of composition are discussed.Departamento de Filología ClásicaGrado en Estudios Clásico
Guernica, el último viaje (2006): Radioteatro de Laila Ripoll
No full textLaila Ripoll es una autora señalada del teatro español contemporáneo, que ha dedicado una parte importante de su obra al tema de la Memoria. Como el radioteatro Guernica, el último viaje, dramatización de un episodio de la Guerra Civil que se ha convertido en un símbolo universal. El texto fue emitido en 2006, con motivo del 25 aniversario del regreso del cuadro a España en 1981. La historia revive a través de la narración del Toro, la Yegua y el Gallo, que aparecen en el cuadro, cobran vida, toman la palabra e interactúan con Picasso y otros personajes. El artículo recoge los resultados de la investigación sobre las estrategias y las técnicas de dramatización del acontecimiento. Entre ellas, destacan la animación y antropomorfización de las figuras del cuadro, la presencia de los muertos vivientes –característicos del teatro de Ripoll–, como Picasso, sus parejas y el arquitecto Josep Lluís Sert, que encargó la obra al artista en nombre del Gobierno de la República española, y el papel de Guernica (acontecimiento, lugar y pintura) como depósito de Memoria.
Laila Ripoll is an outstanding author of contemporary Spanish theatre, who has dedicated an important part of her work to the theme of Memory. Like the radiodrama Guernica, el ultimo viaje, a dramatisation of an episode of the Civil War that has become a universal symbol. The text was issued in 2006, on the occasion of the 25th anniversary of the painting\u27s return to Spain in 1981. The story is brought to life by some of the figures of the painting, the Bull, the Mare and the Cockerel, who come to life, speak and interact with Picasso and other characters. The article summarises the results of the research on the strategies and techniques of dramatisation of the event. These include the animation and anthropomorphisation of the characters of the painting, the presence of the muertos vivientes, characteristic of Ripoll’s theatre, such as Picasso, his partners and the architect Josep Lluís Sert, who commissioned the work from the artist on behalf of the Government of the Spanish Republic, and the role of Guernica (the event, the place and the painting) as a repository of Memory.Laila Ripoll es una autora señalada del teatro español contemporáneo, que ha dedicado una parte importante de su obra al tema de la Memoria. Como el radioteatro Guernica, el último viaje, dramatización de un episodio de la Guerra Civil que se ha convertido en un símbolo universal. El texto fue emitido en 2006, con motivo del 25 aniversario del regreso del cuadro a España en 1981. La historia revive a través de la narración del Toro, la Yegua y el Gallo, que aparecen en el cuadro, cobran vida, toman la palabra e interactúan con Picasso y otros personajes. El artículo recoge los resultados de la investigación sobre las estrategias y las técnicas de dramatización del acontecimiento. Entre ellas, destacan la animación y antropomorfización de las figuras del cuadro, la presencia de los muertos vivientes –característicos del teatro de Ripoll–, como Picasso, sus parejas y el arquitecto Josep Lluís Sert, que encargó la obra al artista en nombre del Gobierno de la República española, y el papel de Guernica (acontecimiento, lugar y pintura) como depósito de MemoriaOn Laila Ripoll\u27s theatr
Francoist repression and moral reparation in the theatre of Laila Ripoll
No full textThis article focuses on a corpus of dramatic texts by Laila Ripoll that denounce how the Spanish Civil War, the Francoist dictatorship and Republican exile marked the lives of the people involved, those of their children and those of generations to come.
The author highlights the collective responsibility of the creative community to reveal details left out from the past by an authoritarian regime and specifically emphasises that this ethical stance is linked to the outlook of their generation, that of the grandchildren of war.
The works chosen demonstrate that members of this third generation of victims are attempting to incorporate the events experienced by their ancestors into the public memory, supported by in-depth research work.
The article also argues that to do this, Ripoll makes use of the critical power of the grotesque aesthetic, a longstanding tradition on the Spanish stage
El monasterio de Santa María de Ripoll: escuela y literatura en torno al abad Oliba (primera mitad del siglo XI). Edición de textos
No full textThe rigorous critical edition of the epistolar anthology copied in ms. Paris, BNF lat. 2858 and the unpublished Translatio Sancti Stephani aim to contribute to the knowledge of the literaryes ideas prevailing at Ripoll at the time of abbot Oliba, and it want especially enhance that the elaboration of these ideas has to be seen as an evolution of previous rhetorical models.La edición filológicamente cuidada de la antología epistolar copiada al ms. París, BNF lat. 2858, y de la inédita Translatio sancti Stephani pretende contribuir al conocimiento de las ideas literarias presentes en Ripoll en la época del abadiado de Oliba, considerando sobre todo que la elaboración de estas ideas se tiene que ver como una evolución con respecto a modelos retóricos precedentes
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