Search results for "Stability."

Grid-Forming Converters in Weak Grids – The Case of a Mediterranean Island

2019

The existing power network of a Mediterranean island is used as test bed for the study of grid-forming converter dynamics in weak grid conditions. The control scheme adopted for the converter falls in the category of the so called virtual synchronous machines (VSM). Particular attention is committed to the interaction between the converter controls and the synchronous machines dynamics. Time delays typically associated to measurements and filters are considered in the study, and included in the system model with a specific mathematical approach. Time-domain simulations show the occurrence of oscillatory instability in the system, with VSM and synchronous machines swinging against each other…

Logical Consensus for Distributed Network Agreement

2008

In this paper we introduce a novel consensus mechanism where agents of a network are able to share logical values, or Booleans, representing their local opinions on e.g. the presence of an intruder or of a fire within an indoor environment. Under suitable joint conditions on agents? visibility and communication capability, we provide an algorithm generating a logical linear consensus system that is globally stable. The solution is optimal in terms of the number of messages to be exchanged and the time needed to reach a consensus. Moreover, to cope with possible sensor failure, we propose a second design approach that produces robust logical nonlinear consensus systems tolerating a maximum n…

THE NEW ARCHITECTURE OF THE EUROPEAN ECONOMIC GOVERNANCE AND ITS CONSTITUTIONAL IMPLICATIONS AT THE EU AND NATIONAL LEVEL

La tesi analizza la nuova architettura costituzionale della governance economica europea come ridefinita dalle più recenti riforme europee predisposte al fine di contrastare la crisi economico-finanziaria dell’area euro e il suo impatto sull’assetto costituzionale dell’Unione europea e degli Stati Membri. La tesi, articolata in quattro capitoli e redatta interamente in lingua inglese, ripercorre le tappe salienti dell’evoluzione dell’Unione Economica e Monetaria, analizza le principali disposizioni della “costituzione economica” dell’Unione europea e contiene un’esposizione, in chiave critica, delle principali misure adottate dall’Unione europea per contrastare la crisi economica della zona…

Random Stability of an Additive-Quadratic-Quartic Functional Equation

2010

Using the fixed point method, we prove the generalized Hyers-Ulam stability of the following additive-quadratic-quartic functional equation f(x+2y)+f(x−2y)=2f(x+y)+2f(−x−y)+2f(x−y)+2f(y−x)−4f(−x)−2f(x)+f(2y)+f(−2y)−4f(y)−4f(−y) in complete random normed spaces.

Can the tumor-agnostic evaluation of MSI/MMR status be the common denominator for the immunotherapy treatment of patients with several solid tumors?

2022

Alterations in short-repetitive DNA sequences, known as microsatellite instability (MSI), can reflect deficiencies in Mismatch Repair (MMR) system which represents a major player in DNA integrity maintenance. The incidence of MSI-H/dMMR has been shown to be variable depending on the tumor type. Several studies confirmed that dMMR/MSI status, although less frequent than PD-L1 expression, may better predict response to immune-checkpoint inhibitors (ICIs) in patients with solid tumors. In October 2016, the FDA granted pembrolizumab as breakthrough therapy for the treatment of non-CRC, MSI-H/dMMR tumors, providing, for the first time, a tumor-agnostic indication. In the next future, the tissue-…

Editorial

2016

The purpose of this special issue is to offer different perspectives on finance sustainability and to develop analytical frameworks for the analysis of the drivers of sustainability at a firm and industry level. Financial mechanisms, instruments, markets, risk management techniques, and business models are identified and their interactions are examined and discussed in the following papers.

Persistent Employment Instability and Fertility Intentions in Italy

2014

Our paper adds to the growing literature on the measurement of employment instability and on that on its consequences on fertility dynamics. We argue that many of these studies disregard a crucial dimension of employment instability: its persistence (duration). It is the persistence in an unstable condition, more than the status itself, that may have the most severe consequences on subsequent family choices. In this paper, we propose an index of persistence in employment instability that synthesizes all the information inside the individual sequence of employment statuses in a single number accounting simultaneously for the duration, sequencing, intensity, and labour market circumstances. T…

Bending Instability of an Accretion Disc Around a Black Hole

2001

We demonstrate that generically an accretion disk around a compact object could have a new type of instability in that the accretion flow need not be symmetric with respect to the equatorial plane even when matter is supplied symmetrically farther out. We find that this behaviour is mainly due to interaction of outgoing matter bounced off the centrifugal barrier and the incoming accretion. We believe that X-ray variability could be developed by this instability.

A flux-split algorithm applied to conservative models for multicomponent compressible flows

2003

In this paper we consider a conservative extension of the Euler equations for gas dynamics to describe a two-component compressible flow in Cartesian coordinates. It is well known that classical shock-capturing schemes applied to conservative models are oscillatory near the interface between the two gases. Several authors have addressed this problem proposing either a primitive consistent algorithm [J. Comput. Phys. 112 (1994) 31] or Lagrangian ingredients (Ghost Fluid Method by Fedkiw et al. [J. Comput. Phys. 152 (1999) 452] and [J. Comput. Phys. 169 (2001) 594]). We solve directly this conservative model by a flux-split algorithm, due to the first author (see [J. Comput. Phys. 125 (1996) …

Active tectonics, sedimentation history and geomorphological features in the northern Sicily continental margin: implications for the marine geohazar…

2020

Starting from the assumption that seismic events in the active margins are accompanied by evidence of a depositional, geomorphologic and structural type, which constitutes the geological record of their activity, we analysed different features of the Northern Sicily continental margin (NSCM) to reconstruct the deformational field and related stress field in the Southern Tyrrhenian sea. As an outcome of this project we were going to obtain seismotectonic setting and mapping to provide a powerful tool in managing and assessing the marine geological hazards. The study area extends from the San Vito Peninsula to the Termini Gulf along the NSCM, including the Ustica island, and is located in a t…