541 research outputs found
Il Carcer nella produzione di Cardano
No full textAlongside a larger analysis of Cardano's moral philosophy since the De consolatione (1542), the essay focuses on the dialogue Carcer, and suggests a relationship between the difficulties encountered by the author in the Duchy of Milan in 1560-61, and the trial of 1570 in Bologna. Special attention is devoted to the philosophical reasons that support in the Carcer the Plutarchean sera numinis vindicta, one of Cardano's favorites topics
Comparing three possible hypoelliptic Laplacians on the 5-dimensional Cartan group via div-curl type estimates
No full textOn general Carnot groups, the definition of a possible hypoelliptic Hodge-Laplacian on forms using
the Rumin complex has been considered in (M. Rumin, “Differential geometry on C-C spaces and application
to the Novikov-Shubin numbers of nilpotent Lie groups,” C. R. Acad. Sci., Paris Sér. I Math., vol. 329, no. 11, pp.
985–990, 1999, M. Rumin, “Sub-Riemannian limit of the differential form spectrum of contactmanifolds,” Geom.
Funct. Anal., vol. 10, no. 2, pp. 407–452, 2000), where the author introduced a 0-order pseudodifferential operator
on forms. However, for questions regarding regularity for example, where one needs sharp estimates, this
0-order operator is not suitable. Up to now, there have only been very few attempts to define hypoelliptic Hodge-
Laplacians on forms that would allow for such sharp estimates. Indeed, this question is rather difficult to address
in full generality, the main issue being that the Rumin exterior differential dc is not homogeneous on arbitrary
Carnot groups. In this note, we consider the specific example of the free Carnot group of step 3 with 2 generators,
and we introduce three possible definitions of hypoelliptic Hodge-Laplacians.We compare how these three possible
Laplacians can be used to obtain sharp div-curl type inequalities akin to those considered by Bourgain &
Brezis and Lanzani & Stein for the de Rham complex, or their subelliptic counterparts obtained by Baldi, Franchi
& Pansu for the Rumin complex on Heisenberg groups
Parametric fluorescence in periodically poled LiNbO<sub>3</sub> buried waveguides
No full textWe report on the periodic poling of LiNbO3 buried waveguides fabricated by reverse proton exchange. We evaluate their linear and nonlinear quadratic properties with the aid of parametric fluorescence
Possession
No full textThis chapter of the Historical Latin Syntax traces the evolution and use of predicative possessive constructions from Archaic to Late Latin. We demonstrate that, far from being merely a so-called “be-language”, Latin is a language where the major possessive type is based on a transitive verb (habeo) since the archaic stage. A textual, contrastive analysis of the habeo x and mihi est x types proves that between these two constructions there is a functional differentiation (i.e. syntactic and pragmatic, while the semantic level is relevant only to a minor extent). This, thus, explains: their different occurrence in the Latin corpus; their division-of-labour and, therefore, their coexistence through the history of Latin; and, finally, the diahronic evolution towards the transitive type. A comparison between the mihi est x and the genitive predicative type, which are fully differentiated on a functional plane, completes the picture of the whole architecture of predicative possession in Latin. Consequences can be drawn on the general plane, as “mixted” types (i.e. languages that are both have- and be-), such as Latin, must be taken into consideration when we approach the typology of predicative possession.
An analysis of attributive constructions is then offered, at the light of parameters such as: the order of the elements in the sequence, the definite status of the possessor/possessum constituents of the phrase, the semantic profile of the relation expressed, and the different morphological markers, etc.. Conclusions partly confirm previous hypotheses about the relation between the Latin stage and the Indoeuropean stage, while several generalizations from the typological point of view have to be adjusted (e.g. external possessor constructions).
The part on predicative possession is mainly due to Andrea Nuti; the part on attributive possession mainly to Philip Baldi. However, as the whole chapter is the result of a deep, mutual work carried on in full cooperation, the authors have agreed not to state explicitly and neatly an author-to-pages correspondence
Macchine per leggere: promuovere la lettura con il distant reading
No full textWe present Macchine per leggere project, a collaboration between the Department of Literary, Philosophical and Art History Studies of the university of Rome “Tor Vergata” and the MiC Center for Books and Reading. The project aims at creating a digital environment (desktop and mobile) that introduces secondary school students to the knowledge and use of computational text analysis as a cue for approaching the reading of classics of Italian literature (among others that will be made available on the site, Il piacere, I Malavoglia, Il fu Mattia Pascal...). The distant reading approach and a set of computer tools for corpus analysis and text mining (word cloud, term and syntagma frequency indices, topic modeling, sentiment, and network analysis), combined with other resources such as geolocation on digital maps of literary places, will be presented both as a method for simulating reading strategies in a virtual environment and as models for integrating traditional hermeneutic practices-close reading. In a dedicated section of the site, the various tools will be available to students in the form of a web application so that they can experiment independently and on other texts in their possession with the distant approach proposed as part of the project.Questo articolo presenta il progetto Macchine per leggere, nato dalla collaborazione tra il Dipartimento di Studi letterari, filosofici e di storia dell’arte dell’Università di Roma “Tor Vergata” e il Centro per il Libro e la Lettura del MiC. Scopo del progetto è la realizzazione di un ambiente digitale (desktop e mobile) che introduca gli studenti della scuola secondaria di secondo grado alla conoscenza e all’utilizzo delle tecniche di analisi computazionale dei testi, qui proposte come spunto per accostarsi alla lettura dei classici della letteratura italiana (tra gli altri che saranno resi disponibili sul sito, Il piacere, I Malavoglia, Il fu Mattia Pascal…). L’approccio del distant reading e gli strumenti informatici per l’analisi e la rappresentazione dei corpora e per il text mining (word cloud, indici di frequenza di termini e sintagmi, topic modeling, sentiment e network analysis), uniti ad altre risorse come la geolocalizzazione su mappe digitali dei luoghi letterari, saranno presentati sia come metodo per simulare in ambiente virtuale reading strategies, che come modelli per integrare le prassi ermeneutiche tradizionali – close reading. In una sezione del sito dedicata, gli algoritmi di cui si darà dimostrazione saranno a disposizione degli studenti in forma di web app, così che possano sperimentare in autonomia e su altri testi in loro possesso l’approccio distant proposto nell’ambito del progetto
Adaptive synchronization in networks with heterogeneous uncertain Kuramoto-like units
No full textWe analyze adaptive synchronization capabilities in networks with Kuramoto-like units whose dynamical features are unknown and thus synchronization protocols must exhibit co-evolution capabilities. In the presence of heterogeneous and uncertain units, synchronization should be enabled by appropriate adaptive protocols that counteract the effect of heterogeneity. An interaction protocol is presented that is used by the units to communicate with each other: the protocol is based on a distributed disagreement measure. The aim of the protocol is to adapt feedback and coupling gains, so as to guarantee the emergence of a synchronous solution. The adaptive strategy is distributed, i.e. each unit self-determines the strength of its gains by using only neighboring measurements. Convergence of the synchronization error to zero is shown via Lyapunov analysis, and numerical examples demonstrate the effectiveness of the proposed protocol.Accepted Author ManuscriptTeam Bart De Schutte
Network Virtual Machine (NetVM): A New Architecture for Efficient and Portable Packet Processing Applications
No full textA challenge facing network device designers, besides increasing the speed of network gear, is improving its programmability in order to simplify the implementation of new applications (see for example, active networks, content networking, etc). This paper presents our work on designing and implementing a virtual network processor, called NetVM, which has an instruction set optimized for packet processing applications, i.e., for handling network traffic. Similarly to a Java Virtual Machine that virtualizes a CPU, a NetVM virtualizes a network processor. The NetVM is expected to provide a compatibility layer for networking tasks (e.g., packet filtering, packet counting, string matching) performed by various packet processing applications (firewalls, network monitors, intrusion detectors) so that they can be executed on any network device, ranging from expensive routers to small appliances (e.g. smart phones). Moreover, the NetVM will provide efficient mapping of the elementary functionalities used to realize the above mentioned networking tasks upon specific hardware functional units (e.g., ASICs, FPGAs, and network processing elements) included in special purpose hardware systems possibly deployed to implement network devices
Valuing a Leveraged Buyout: Expansion of the Adjusted Present Value by means of Real Options Analysis
No full textA major flaw in using the adjusted present value (APV) method to value the target firm of a leveraged buyout is that it results in systematic undervaluation of the firm in question. The author proposes to remedy the problem by employing real options analysis to expand the target firm's APV on its equity side. Two real options may be identified as being inherent in the leveraged buyout structuring process: a financial default call option and an operating default call option, both of American type. The resulting expanded equity value allows for the flexible management of firm value uncertainty while continuing to incorporate the extra value creation deriving from the exploitation of the tax shield
Numerical and Experimental Analyses of Multiple Delaminations in Curved Composite Laminates
No full textA distributed disagreement-based protocol for synchronization of uncertain heterogeneous agents
No full textIn networks with heterogeneous and uncertain agents, fixed-gain control can lead to synchronization only if the uncertainties are relatively small. If the uncertainties are larger, we need to develop adaptive-gain approaches to achieve synchronization. In this work we propose an adaptive synchronization protocol, in case of full-state measurement, for uncertain heterogeneous agents based on a distributed disagreement reasoning. Specifically, we first define unknown gains (feedback and coupling gains) that could lead all agents to a homogeneous behavior and thus synchronization: however, since these gains are unknown in view of the unknown dynamics, we design adaptive laws for these gains that lead the agents toward synchronization. The adaptive laws are driven by a disagreement error which is calculated among neighbors: a Lyapunov analysis is presented for showing convergence of the synchronization error to zero.Accepted Author ManuscriptTeam Bart De Schutte
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