Regular R-R and NS-NS BPS black holes

We show in a precise group theoretical fashion how the generating solution of regular BPS black holes of N=8 supergravity, which is known to be a solution also of a simpler N=2 STU model truncation, can be characterized as NS-NS or R-R charged according to the way the corresponding STU model is embedded in the original N=8 theory. Of particular interest is the class of embeddings which yield regular BPS black hole solutions carrying only R-R charge and whose microscopic description can possibly be given in terms of bound states of D-branes only. The microscopic interpretation of the bosonic fields in this class of STU models relies on the solvable Lie algebra (SLA) method. In the present article we improve this mathematical technique in order to provide two distinct descriptions for type IIA and type IIB theories and an algebraic characterization of S*T--dual embeddings within the N=8,d=4 theory. This analysis will be applied to the particular example of a four parameter (dilatonic) solution of which both the full macroscopic and microscopic descriptions will be worked out.Comment: latex, 30 pages. Final version to appear on Int.J.Mod.Phy

Arithmetic with Language Models: from Memorization to Computation

A better understanding of the emergent computation and problem-solving capabilities of recent large language models is of paramount importance to further improve them and broaden their applicability. This work investigates how a language model, trained to predict the next token, can perform arithmetic computations generalizing beyond training data. Binary addition and multiplication constitute a good testbed for this purpose, since they require a very small vocabulary and exhibit relevant input/output discontinuities making smooth input interpolation ineffective for novel data. We successfully trained a light language model to learn these tasks and ran a number of experiments to investigate the extrapolation capabilities and internal information processing. Our findings support the hypotheses that the language model works as an Encoding-Regression-Decoding machine where the computation takes place in the value space once the input token representation is mapped to an appropriate internal representation

Face morphing detection in the presence of printing/scanning and heterogeneous image sources

Face morphing represents nowadays a big security threat in the context of electronic identity documents as well as an interesting challenge for researchers in the field of face recognition. Despite of the good performance obtained by state-of-the-art approaches on digital images, no satisfactory solutions have been identified so far to deal with cross-database testing and printed-scanned images (typically used in many countries for document issuing). In this work, novel approaches are proposed to train Deep Neural Networks for morphing detection: in particular generation of simulated printed-scanned images together with other data augmentation strategies and pre-training on large face recognition datasets, allowed to reach state-of-the-art accuracy on challenging datasets from heterogeneous image sources

On the Feasibility of Creating Double-Identity Fingerprints

A double-identity fingerprint is a fake fingerprint created by combining features from two different fingers, so that it has a high chance to be falsely matched with fingerprints from both fingers. This paper studies the feasibility of creating double-identity fingerprints by proposing two possible techniques and evaluating to what extent they may be used to fool the state-of-the-art fingerprint recognition systems. The results of systematic experiments suggest that existing algorithms are highly vulnerable to this specific attack (about 90% chance of success at FAR = 0.1%) and that the fingerprint patterns generated might be realistic enough to fool human examiners

Sliding mode control of constrained nonlinear systems

This technical note introduces the design of sliding mode control algorithms for nonlinear systems in the presence of hard inequality constraints on both control and state variables. Relying on general results on minimum-time higher-order sliding mode for unconstrained systems, a general order control law is formulated to robustly steer the state to the origin, while satisfying all the imposed constraints. Results on minimum-time convergence to the sliding manifold, as well as on the maximization of the domain of attraction, are analytically proved for the first-order and second-order sliding mode cases. A general result is presented regarding the domain of attraction in the general order case, while numerical results on the estimation of the domain of attraction and on minimum-time convergence are discussed for the third-order case, following a procedure applicable to a sliding mode of any order

IL RUOLO DELLE BANCHE LOCALI NEL PROCESSO DI CONCENTRAZIONE DEL SETTORE. CASO BANCO DI LUCCA S.P.A

Negli ultimi due decenni gli equilibri dei mercati finanziari mondiali sono stati scossi da cambiamenti di natura strutturale. A ciò ha contribuito un insieme articolato di fattori, sia normativi che economici. In primo luogo il progresso tecnologico ha offerto nuove opportunità per migliorare l’efficienza aziendale e per contenere i costi di distribuzione dei servizi. I grandi gruppi bancari e finanziari hanno implementato nuovi assetti organizzativi basati sulla concentrazione delle “funzioni” tra loro omogenee, quali ad esempio i sistemi informativi, la gestione degli investimenti e l’amministrazione. Il settore bancario italiano, a partire degli anni Novanta, è stato interessato da un intenso processo di concentrazione. Nel periodo compreso tra il 1991 e il 2006 sono state realizzate oltre 500 operazioni di fusione e acquisizione . Le stesse hanno determinato una netta riduzione del numero di banche operanti in Italia. La tendenza alla globalizzazione comporta un elevato rischio, quello che venga meno il rapporto tra banca locale e territorio. In altri termini, conduce alla perdita di una serie di legami storici ed economici tra comunità e banca locale e al venir meno di un rapporto diretto, di conoscenza e fiducia, tra banca ed il mondo della piccola e media impresa. In questo contesto, interessanti sono gli spazi di operatività per le banche locali. Tali banche sarebbero in grado di favorire un ritorno al rapporto personale con il cliente; si assiste ad un rinnovato interesse per il concetto di localismo, che esalta l’attività dell’intermediario bancario locale. La banca locale può essere considerata come “categoria analitica autonoma” , ossia una particolare formula imprenditoriale che, rispetto ad altri tipi di banca, possiede caratteri di spiccata autonomia. Quest’ultima si sostanzia nel ruolo specifico che svolge all’interno dei processi di produzione e di comunicazione delle informazioni nei sistemi locali. A ben vedere, il concetto di banca locale si coglie guardando al modus operandi della banca, senza confonderlo con quello di banca di minori dimensioni. Una banca si considera locale quando la sua attività “viene condotta secondo logiche di stretta correlazione con il tessuto economico - sociale di insediamento” .Elementi caratteristici della banca locale sono rappresentati dal forte radicamento territoriale, dalla stabile relazione con il territorio di vocazione e dal supporto offerto agli operatori economici locali. La banca locale ha un ruolo predominante nel nostro sistema imprenditoriale, in quanto è chiamata ad istaurare delle relazioni di lungo periodo con la piccola e media impresa e a far fluire una gamma di offerta, appositamente studiata, per le esigenze e per i profili socio - economici delle realtà locali. La vicinanza tra banca locale e piccola e media impresa (PMI) porta a molteplici vantaggi sia per la banca che per l’impresa. Per la banca, il beneficio sta nel valutare con maggior precisione i rischi degli affidamenti (sia in fase di screening che di monitoring), per la PMI, è ricondotto alla risoluzione delle difficoltà legate all’approvvigionamento delle risorse finanziarie. Quest’ultimo è un aspetto rilevante; in assenza di banche locali tali imprese potrebbero rimanere escluse dal circuito creditizio, pena il mancato sviluppo economico dell’area in cui esse insistono. La vocazione locale della banca, pertanto, conduce ad una convergenza di interessi con le imprese operanti nel territorio. Accade, infatti, che le banche locali siano percepite, dagli operatori economici dell’area di riferimento, come dei centri per la crescita economica di tali aree. In questo modo è accentuato il ruolo delle banche locali, intese come “banche di riferimento” che possono fungere da volano per la crescita del territorio. Ciò implica un ridisegno dell’organizzazione funzionale, secondo approcci diversi rispetto a quelli del recente passato. In altre parole, si richiede alla banca locale di regolare la sua operatività in funzione del territorio di riferimento. La banca locale dovrà dimostrare di saper rispondere agli stimoli esterni, rivisitando i modelli strategici originari, senza perdere mai di vista i vantaggi legati alle proprie caratteristiche. Il presente lavoro si propone di delineare le opzioni strategiche, che la banca locale è chiamata ad attuare in un contesto che le impone rilevanti sfide. Il lavoro è completato dall’analisi di un caso specifico : il Banco di Lucca dove ho vissuto un’esperienza di tre mesi in un momento che considero storico per questa banca in quanto è stata acquisita dalla “Cassa di Risparmio di Ravenna” e in forza di questo passaggio che ha dato maggiore spinta manageriale, strutturale ed economica la banca lucchese si rilancerà ancora di più come banca di riferimento del “suo” territorio

A Double Siamese Framework for Differential Morphing Attack Detection

Face morphing and related morphing attacks have emerged as a serious security threat for automatic face recognition systems and a challenging research field. Therefore, the availability of effective and reliable morphing attack detectors is strongly needed. In this paper, we proposed a framework based on a double Siamese architecture to tackle the morphing attack detection task in the differential scenario, in which two images, a trusted live acquired image and a probe image (morphed or bona fide) are given as the input for the system. In particular, the presented framework aimed to merge the information computed by two different modules to predict the final score. The first one was designed to extract information about the identity of the input faces, while the second module was focused on the detection of artifacts related to the morphing process. Experimental results were obtained through several and rigorous cross-dataset tests, exploiting three well-known datasets, namely PMDB, MorphDB, and AMSL, containing automatic and manually refined facial morphed images, showing that the proposed framework was able to achieve satisfying results

Robust Model Predictive Control With Integral Sliding Mode in Continuous-Time Sampled-Data Nonlinear Systems

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A holistic life cycle design approach to enhance the sustainability of concrete structures

The development of innovative cementitious materials such as Ultra High Performance Concrete (UHPC) requires tailored approaches to assess both the environmental and economic impact of structural applications employing them. For this purpose, in this paper, Life Cycle Assessment (LCA) and Life Cycle Cost (LCC) methodologies are integrated into a Durability Assessment-Based Design (DAD) workflow which combines structural design algorithms for UHPC with the assessment of the durability performance, with the aim of predicting the evolution of the structural performance all along the service life (SL) in the intended scenarios. As a case study a water tank made of UHPC has been herein selected and compared to a reference made of Ordinary Reinforced Concrete (ORC). While the ORC solution was designed with cantilever cast in situ walls, two different design concepts were assessed for the UHPC basin: one with cast in situ walls and one with precast slabs supported by ORC columns. Moreover, two different mix designs (mainly differing on the alternative presence of silica fume or slag) have been investigated for the UHPC basin and a SL equal to 50 years has been taken into account for each structure. The optimized design, together with the reduced frequency of the maintenance activities for the UHPC structure, allowed by the UHPC superior material and structural durability, resulted into consistent reductions of environmental impacts, up to 76% as for Human Toxicity and Fresh Water Aquatic Ecotoxicity in comparison to the ORC solution. In addition to this, an assessment of the overall construction and maintenance costs that occur during the lifetime of the structures showed a cost reduction higher than 40% for both UHPC solutions, mainly due to a reduction of up to 6% during the construction phase and 91% for the maintenance activities. This also highlights the importance of the correct metrics in evaluating the sustainability of UHPC structural applications, which has to move forward from the units volume or mass of material and its individual constituents to functional units, represThe development of innovative cementitious materials such as Ultra High Performance Concrete (UHPC) requires tailored approaches to assess both the environmental and economic impact of structural applications employing them. For this purpose, in this paper, Life Cycle Assessment (LCA) and Life Cycle Cost (LCC) methodologies are integrated into a Durability Assessment-Based Design (DAD) workflow which combines structural design algorithms for UHPC with the assessment of the durability performance, with the aim of predicting the evolution of the structural performance all along the service life (SL) in the intended scenarios. As a case study a water tank made of UHPC has been herein selected and compared to a reference made of Ordinary Reinforced Concrete (ORC). While the ORC solution was designed with cantilever cast in situ walls, two different design concepts were assessed for the UHPC basin: one with cast in situ walls and one with precast slabs supported by ORC columns. Moreover, two different mix designs (mainly differing on the alternative presence of silica fume or slag) have been investigated for the UHPC basin and a SL equal to 50 years has been taken into account for each structure. The optimized design, together with the reduced frequency of the maintenance activities for the UHPC structure, allowed by the UHPC superior material and structural durability, resulted into consistent reductions of environmental impacts, up to 76% as for Human Toxicity and Fresh Water Aquatic Ecotoxicity in comparison to the ORC solution. In addition to this, an assessment of the overall construction and maintenance costs that occur during the lifetime of the structures showed a cost reduction higher than 40% for both UHPC solutions, mainly due to a reduction of up to 6% during the construction phase and 91% for the maintenance activities. This also highlights the importance of the correct metrics in evaluating the sustainability of UHPC structural applications, which has to move forward from the units volume or mass of material and its individual constituents to functional units, representative of the benefits of using advanced cement based materials in structurally and environmentally challenging service scenarios. entative of the benefits of using advanced cement based materials in structurally and environmentally challenging service scenarios