255 research outputs found
Timed automata with urgent transitions
No full textIn this paper we propose an extension to the formalism of timed automata by
allowing urgent transitions. A urgent transition is a transition which must be taken
within a fixed time interval from its enabling time. We give a set of rules formally
describing the behaviour of urgent transitions and we show that, from a language
theoretic point of view, the addition of urgency does not improve the expressive
power of timed automata. However, from a specification point of view, the use of
urgent transitions is crucial, especially in modular specification of systems
Ripensare l’offerta turistica e culturale negli scenari COVID-19. Una sfida aperta.
No full textIl momento storico generato dalla pandemia di Covid-19 ha accentuato la consapevolezza del carattere centrale delle opportunità offerte dai territori in termini di qualità, fruibilità e accessibilità dei luoghi e del patrimonio culturale, consolidando il ruolo strategico dei piani per il turismo lento e sostenibile, capaci di consentire le condizioni per un modello di esperienza di visita immersiva, distante dalle pratiche di consumo dei luoghi tipiche del turismo di massa.
La direzione cui indirizzare le politiche di rilancio del settore turistico duramente prostrato dalla pandemia è il turismo living site, che può ben essere considerato il modello in grado di mantenere vivo il settore in qualsiasi situazione sanitaria, sociale e culturale, sempre sostenibile e in grado di rivitalizzare ecosistemi sottostimati e destinati a scomparire, garantendone, nel contempo, la tutela proprio grazie alla salvaguardia e alla valorizzazione delle molteplici, autentiche identità
An Abstract Interpretation Approach for Enhancing the Java Bytecode Verifier
No full textThe Java virtual machine embodies a verifier that performs a set of checks on Java bytecode programs before their execution. The verifier carries out an efficient data-flow analysis applied to a type-level abstract interpretation of the code. The implementations of the bytecode verifier presented a significant problem with programs compiled with the Sun Java compiler (until version 1.4.1): there were legal Java programs which were correctly compiled into a bytecode that was rejected by the verifier. The problem was fixed by removing, in version 1.4.2 and following, some interesting features in the compilation of the try-finally Java construct. Because removing such features has a cost in terms of memory space, in this paper we propose to enhance the bytecode verifier to accept such programs, maintaining the space efficiency of the previous versions of the compiler. We define an abstract interpretation framework in which we model the enhanced version of the verifier. The defined abstract interpretation framework can be considered a good basis for other static analyses of bytecode programs
Neuropeptide Y is an essential in vivo developmental regulator of cardiac I-Ca,I-L
No full textCell culture studies demonstrate an increase in cardiac L-type Ca2+ current (I-Ca,I-L) density on sympathetic innervation in vitro and suggest the effect depends on neurally released neuropeptide Y (NPY). To determine if a similar mechanism contributes to the postnatal increase in I-Ca,I-L in vivo, we prepared isolated ventricular myocytes from neonatal and adult mice with targeted deletion of the NPY gene (Npy(-/-)) and matched controls (Npy(+/+)). Whole-cell voltage clamp demonstrates I-Ca,I-L density increases postnatally in Npy(+/+) (by 56%), but is unchanged in Npy(-/-). Both I-Ca,I-L density and action potential duration are significantly greater in adult Npy(+/+) than Npy(-/-) myocytes, whereas I-Ca,I-L density is equivalent in neonatal Npy(+/+) and Npy(-/-) myocytes. These data indicate NPY does not influence ICa,L prenatally, but the postnatal increase in I-Ca,I-L density is entirely NPY-dependent. In contrast, there is a similar postnatal negative voltage shift in the I-V relation in Npy(+/+) and Npy(-/-), indicating NPY does not influence the developmental change in I-Ca,I-L voltage-dependence. Immunoblot analyses and measurements of maximally activated I-Ca,I-L (in presence of forskolin or BayK 8644) show that the differences in current density between Npy(+/+) and Npy(-/-) cannot be attributed to altered Ca2+ channel alpha(1C) subunit protein expression. Rather, these results suggest that the in vivo NPY-dependent postnatal increase in I-Ca,I-L density in cardiac myocytes results from regulation I-Ca,I-L properties by NPY
Analisi della bugia in età evolutiva: uno studio sperimentale sulle differenze di genere.
No full text
Rethinking the Tourist and Cultural Offer in COVID-19 Scenarios. An open challenge
No full textThe paper identifies and discusses the traits that characterize some good practices of slow tourism offered by operators in the Apulian and Lucanian regions, as well as the critical issues that hinder the conditions of recovery, albeit difficult and partial
Rethinking the Tourist and Cultural Offer in COVID-19 Scenarios. An open challenge
No full textTourism has been progressively characterized to an increasingly marked extent by two important transformation processes: one relating to the broader number of subjects who aspire to create a travel experience; the other connected to the increasingly experiential nature of the travel. The current health emergency linked to the spread of the Covid19 virus has deeply modified this trend, which has been increasing over the past twenty years. The need to guarantee the health safe of travellers has today and in the future a first-rate impact not only on the conditions for traveling, but also on the destinations of the trips. The core of the tourist offer even immediately before the pandemic: cities of art, trips organized for groups, stays in large residences and holiday villages, offers of "indoor" places such as museums, churches, royal and noble residences, all of them today are experiencing a profound and unprecedented crisis due to the difficulty of managing significant problems related to safe access. On the other side, the necessary health measures are fostering the increase of a different tourist experience model more oriented towards innovative trends, closely related to cultural and landscape use.
Consequently, what today is, even rightly, still perceived as an element with a devastating impact for the entire national economic system related to tourism, the same may represent the opportunity to generate a push towards experiential directions underestimated in their potential, despite there are successful practices in almost all top level European tourism contexts. An opportunity to clear customs especially those territories and those tour operators in inland areas (but not only...), which had already started a process of enhancement initially aimed at a more niche audience, but which could now represent an important strategic resource not only for them, as it would be able to generate significant development in areas often facing depopulation.
This paper identifies and discusses the traits that characterize some good practices of slow tourism offered by operators in the Apulian and Lucanian regions, as well as the critical issues that hinder the conditions of recovery, albeit difficult and partial
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