oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2017 ( 3 )

2016 ( 3 )

2015 ( 140 )

2014 ( 158 )

Custom range...

Search Results: 1 - 10 of 1943 matches for " Fabrizio Ronci "
All listed articles are free for downloading (OA Articles)
Page 1 /1943
Display every page Item
Embedding Authentication & Authorization in Discovery Protocols for Standard Based Publish/Subscribe Middleware: A Performance Evaluation  [PDF]
Fabrizio Ronci, Marco Listanti
Communications and Network (CN) , 2011, DOI: 10.4236/cn.2011.31006
Abstract: Standard based Pub/Sub middleware, such as OMG Data Distribution Service (DDS), could assume a key role in supporting computer communications requiring continuous state information updating, deterministic deadline to data delivering and real time information adjourning. This kind of capability could be well ex-ploited by Peer-To-Peer (P2P) systems, Internet-wide as long as private ones, like in Public Safety or Civil Protection Communication Systems; but Pub/Sub specifications, and DDS/RTPS (Real Time Publish Sub-scribe) as well, usually do not provide Authentication & Authorization (AA) mechanisms. In the present work two important novelties are assessed: a possible scheme to implement AA in DDS/RTPS networks and a time performance evaluation study about embedded Authentication in RTPS.
Accurate Tools for Analyzing the Behavior of Impulse Noise Reduction Filters in Color Images  [PDF]
Fabrizio Russo
Journal of Signal and Information Processing (JSIP) , 2013, DOI: 10.4236/jsip.2013.41005
Abstract:

Effective cancellation of noise and preservation of color/structural information are features of paramount importance for any filter devoted to impulse noise removal in color images. In this paper novel full-reference tools for analyzing the behavior of this family of filters are presented. The proposed approach is based on the classification of color errors into two main classes that separately take into account the inaccuracy in removing noise pulses and the filtering distortion. The distortion errors are then classified into two subclasses for a deeper analysis of the filtering behavior. Computer simulations show that the proposed method gives more accurate results than using other measures of filtering performance in the literature. Furthermore, the method can easily yield the spatial location of the different filtering features in the image.

Relativistic Derivations of de Broglie and Planck-Einstein Equations  [PDF]
Fabrizio Logiurato
Journal of Modern Physics (JMP) , 2014, DOI: 10.4236/jmp.2014.51001
Abstract:

Special Relativity sets tight constraints on the form of the possible relations between the four-momentum of a particle and the wave four-vector. In fact, we demonstrate that there is just one way, according to Special Relativity, to relate the energy and the momentum of a corpuscle with the characteristics of a plane wave, frequency and wave vector, if the momentum has to flow in the same direction of the wave propagation: the laws must be of direct proportionality like de Broglie \"\" and Planck-Einstein \"\" equations.

First-principles calculations and bias-dependent STM measurements at the alpha-Sn/Ge(111) surface: a clear indication for the 1U2D configuration
P. Gori,F. Ronci,S. Colonna,A. Cricenti,O. Pulci,G. Le Lay
Physics , 2008,
Abstract: The nature of the alpha-Sn/Ge(111) surface is still a matter of debate. In particular, two possible configurations have been proposed for the 3x3 ground state of this surface: one with two Sn adatoms in a lower position with respect to the third one (1U2D) and the other with opposite configuration (2U1D). By means of first-principles quasiparticle calculations we could simulate STM images as a function of bias voltage and compare them with STM experimental results at 78K, obtaining an unambiguous indication that the stable configuration for the alpha-Sn/Ge(111) surface is the 1U2D. The possible inequivalence of the two down Sn adatoms is also discussed.
Floquet Eigenvectors Theory of Pulsed Bias Phase and Quadrature Harmonic Oscillators  [PDF]
Fabrizio Palma, Stefano Perticaroli
Circuits and Systems (CS) , 2012, DOI: 10.4236/cs.2012.31010
Abstract: The paper presents an analytical derivation of Floquet eigenvalues and eigenvectors for a class of harmonic phase and quadrature oscillators. The derivation refers in particular to systems modeled by two parallel RLC resonators with pulsed energy restoring. Pulsed energy restoring is obtained through parallel current generators with an impulsive characteristic triggered by the resonators voltages. In performing calculation the initial hypothesis of the existence of stable oscillation is only made, then it is verified when both oscillation amplitude and eigenvalues/eigenvectors are deduced from symmetry conditions on oscillator space state. A detailed determination of the first eigenvector is obtained. Remaining eigenvectors are hence calculated with realistic approximations. Since Floquet eigenvectors are acknowledged to give the correct decomposition of noise perturbations superimposed to the oscillator space state along its limit cycle, an analytical and compact model of their behavior highlights the unique phase noise properties of this class of oscillators.
The Response of Benthic Foraminiferal Assemblages to Copper Exposure: A Pilot Mesocosm Investigation  [PDF]
Frontalini Fabrizio, Coccioni Rodolfo
Journal of Environmental Protection (JEP) , 2012, DOI: 10.4236/jep.2012.34044
Abstract: Controlled experiments, including mesocosms and laboratory cultures, are used to identify a potential speci?c cause- effect relationship that has been previously inferred in field studies. In this study, a series of mesocosm experiments are carried out to assess the impact of different concentrations of copper on benthic foraminiferal assemblages over time. This pilot investigation documents that Cu contamination has a detrimental effect on foraminifera when compared to original and control samples. In particular, increased concentrations of Cu (normally higher than 120 μg/l) lead to a lowering of foraminiferal density and diversity and an increased occurrence of abnormalities. This study thus supports that the use of an experimental approach is suitable for investigating the response of benthic foraminifera to stress including pollution. Moreover, the application of mesocosms represents an innovative tool to be placed alongside field studies and culture experiments.
Born Rule and Noncontextual Probability  [PDF]
Fabrizio Logiurato, Augusto Smerzi
Journal of Modern Physics (JMP) , 2012, DOI: 10.4236/jmp.2012.311225
Abstract: We present a new derivation of the Born rule from the assumption of noncontextual probability (NCP). Within the theorem we also demonstrate the continuity of probability with respect to the amplitudes, which has been suggested to be a gap in Zurek’s and Deutsch’s approaches, and we show that NCP is implicitly postulated also in their derivations. Finally, physical motivations of NCP are given based on an invariance principle with respect to a resolution change of measurements and with respect to the principle of no-faster-than-light signalling.
Corporate Governance and Performance: Evidence from Italian Companies  [PDF]
Fabrizio Fratini, Patrizia Tettamanzi
Open Journal of Business and Management (OJBM) , 2015, DOI: 10.4236/ojbm.2015.32020
Abstract: The purpose of this paper is to verify the presence and intensity (extent) of the relationship between corporate governance and performance in Italian listed companies by using both accounting and non-accounting performance measures. We extended previous literature in considering all the main aspects of governance (board structure and ownership structure) and all relevant peculiarities of Italian entrepreneurial system (family business, concentrated ownership, State ownership, pyramidal groups). In the first part of the paper, we used regression analysis on a sample of 182 Italian listed companies to find that firm performance was positively related to board size and audit committee’s effort and negatively related to leverage, although with a very low coefficient. No particular relationship was highlighted for ownership structure. We tested the consistency of this finding by doing a follow-up analysis between a sub-group of 134 of 2003 sample companies and the same companies in 2007 to verify the stability of the determinants of performance and their relative impact overtime. What we found was that only board size kept its positive relation with performance. Audit committee and leverage lost their relevance in 2007 sample in which the presence of a compensation committee showed a positive impact on performance. From our findings, we can conclude that, according to other studies (Belcredi & Rigamonti [1]), the relationship among ownership and corporate governance structure and firm performance is ambiguous. The ambiguity improves if considering the relationship overtime.
Advertising Effectiveness: An Approach Based on What Consumers Perceive and What Advertisers Need  [PDF]
Macarena Estévez, Davide Fabrizio
Open Journal of Business and Management (OJBM) , 2014, DOI: 10.4236/ojbm.2014.23022
Abstract: This paper examines how advertising effectiveness can be defined and measured. We propose a 3D-effectiveness key performance indicator involving the weighted prominence of three factors: recall, brand image and buying intention. In this way, the indicator proposed improves the metrics of this type known in the Spanish market. Using experimental data about 20 fixed brands and other 12 variable brands collected along the 52 weeks of a year, we find that this indicator reflects consumer’s perceptions and that it fits advertising company’s needs. We have developed a web tool to provide the market with a benchmark measure of advertising effectiveness. Finally, we discuss future research lines.
Tax Compliance, Income Distribution and Social Norms  [PDF]
Debora Di Gioacchino, Fabrizio Patriarca
Theoretical Economics Letters (TEL) , 2017, DOI: 10.4236/tel.2017.73044
Abstract: This paper studies the effect of income inequality on tax evasion. To discuss the topic, we present a simple model, based on Benabouand Tirole [1], that incorporates incentives for tax compliance such as punishment and fines, intrinsic motivation and social norms. Since we consider a regressive system of incentives to comply, income inequality increases the value of tax evasion although overall propensity to comply is unaffected. In this framework, we consider the hypothesis that social norms are group specific as in the case of social segregation or status related networks. We show that all the negative effects of inequalities are amplified: the difference between the tax compliance of the income groups and the value of tax evasion increase.
Page 1 /1943
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.