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Coalition Obstruction Temporal Logic:A New Obstruction Logic to Reason about Demon Coalitions
Get PDFIn multi-agent systems, especially in cybersecurity, the dynamic interplay between attackers and defenders is crucial to the security and resilience of the system. Traditional methods often assume static game models and fail to account for the strategic adaptation of the environment to the actions of the players. This paper presents Coalition Obstruction Temporal Logic (COTL), a formal framework for analyzing defender coalitions in dynamic game scenarios. Within this framework, defenders, conceptualized as demons, can actively obstruct attackers by selectively disabling certain actions in response to perceived threats. We establish the formal semantics of COTL and propose a model-checking algorithm to verify complex security properties in systems with evolving adversarial dynamics. The utility of the framework is demonstrated through its application to a coalition of defenders that collaboratively defend a system against coordinated attacks
La protection des acteurs de l’information au sein de l’union européenne, préalable indispensable au droit à l’information du citoyen
No full textLes responsabilités du fait d'autrui:la responsabilité des titulaires de l'autorité sur la personne des mineurs
No full textLes responsabilités du fait d'autrui:la responsabilité des établissements d'enseignement
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Exploring the Synergistic Interplay of Optical, Morphological, and Catalytic Features in Ga-Doped ZnO Nanoparticles:Harnessing Their Potential for Photocatalytic Dye Degradation under UV-Green Light Irradiation
No full textThis work explores the synthesis and characterization of undoped ZnO, Ga-doped ZnO (Ga:ZnO), and γ-Ga2O3 quasi-spherical nanoparticles and their catalytic activity in Rhodamine B photodegradation under UV-visible light exposure. Gallium dopant incorporation into Ga:ZnO was confirmed by inductively coupled plasma optical emission spectroscopy (ICP-OES), Fourier transform infrared (FT-IR), and powder X-ray diffraction (XRD), maintaining the hexagonal wurtzite structure with an additional zinc gallium carbonate Layered Double Hydroxide (LDH) phase at higher dopant concentrations. TEM images revealed no significant alteration in the morphology or size of the nanoparticles. 71Ga-NMR indicated the location of the gallium atoms within the ZnO lattice, showing coordination changes with an increasing dopant concentration. Ga-doped ZnO nanoparticles demonstrated reduced efficiency under UV light compared to commercial references. γ-Ga2O3 exhibited superior performance in UV-C for Rhodamine B degradation, diminishing under UV-A, attributed to nanoparticle agglomeration. ZnO and Ga:ZnO catalysts showed optimal performance under green light irradiation, highlighting their performances over the commercial zinc oxide material. Photoluminescence measurements suggested favorable gallium dopant incorporation, with no substantial variation of oxygen vacancies, consequently retaining the photocatalytic properties of ZnO, which are crucial for Rhodamine B degradation under green light irradiation. This study elucidates the intricate relationship among gallium doping, material properties, and photocatalytic performance, providing valuable insights for developing advanced photocatalysts.</p
Response to synchronization in distance-dependent coupled heterogeneous oscillators
Get PDFFireflies are often presented as a main example of a natural system that exhibits synchronization~[1]. However, there are species of fireflies in which males synchronize first and only after that phase females are capable of exhibiting such unison behavior; stated differently, female fireflies exhibit {\em response to synchronization}~[2]. In this work, we consider a dynamical model based on bursting (male) and nonbursting (female) oscillators~[3] which are closely related to the integrate-and-fire oscillators whose characteristics are shown in Fig~1(a)--(b).The dynamical system composed of is given by Eq. (1),where , according to the oscillator represents a male or a female, respectively, and are the elements of a weighted adjacency matrix and determine the distance-dependent coupling strength, situation depicted in Fig.~1(c).The transition between the states determined by is described by the following relation: Eqs. 2(a)-(c).We first studied the case of a stationary weighted adjacency matrix and secondly we considered a time-varying matrix, the latter mimicking a relatively small motion of oscillators. In both cases, aspects such as transients, clustering, and response temporal patterns are outlined. As an example of the phenomenon, Fig.~1(d) illustrates the response to synchronization for the case of a population of 20 oscillators: 10 males and 10 females.We conclude our work by discussing the potential and possible pitfalls of implementing these dynamic networks on a robotic platform
Une immersion romanesque dans la Rome impériale, sa langue et sa littérature:'La nuit des orateurs' d’Hédi Kaddour
No full text'La nuit des orateurs' est un roman historique publié en 2021 par l'écrivain franco-tunisien Hédi Kaddour. L'intrigue a pour cadre le début de la vague d'exécutions de sénateurs décidée par l'empereur Domitien en 93 apr. J.-C. ; les protagonistes sont Tacite et sa femme. Cette contribution analyse les sources historiques mobilisées par Kaddour et la façon dont l'écrivain a construit les personnages de Tacite et de sa femme en mettant à profit les "blancs" de l'histoire créés par les lacunes de la documentation. Envisagé du point de vue de la vulgarisation historique, ce roman apparaît comme une excellente reconstitution de l'imaginaire romain