3,463 research outputs found
Is the market swayed by press releases on corporate governance? Event study on the Eurostoxx banks
Are press releases on Corporate Governance price sensitive? What is the impact of Corporate Governance information on stock prices of banks? This paper addresses these questions by applying an event study methodology on 70 press releases published by the Euro area banks listed on the Eurostoxx banks Index, from 2007 to 2016. Systemic shocks are explored as well idiosyncratic ones. Our results show that investment decisions are significantly but negatively influenced by the disclosure of a press release on corporate governance as if this kind of news leads investors to perceive the banksâ prospects negatively. The best of our knowledge this is the first paper that investigates European banks press releases on corporate governance. Findings are relevant for banksâ management and their disclosure policy. Nonetheless, further research is needed to investigate differences and similarities between an area of governance disclosure and another
Retrieving Temperatures and Abundances of Exoplanet Atmospheres with High-Resolution Cross-Correlation Spectroscopy
Hi-resolution spectroscopy (R > 25,000) has recently emerged as one of the
leading methods to detect atomic and molecular species in the atmospheres of
exoplanets. However, it has so far been lacking in a robust method to extract
quantitative constraints on temperature structure and molecular/atomic
abundances. In this work we present a novel Bayesian atmospheric retrieval
framework applicable to high resolution cross-correlation spectroscopy (HRCCS)
that relies upon the cross-correlation between data and models to extract the
planetary spectral signal. We successfully test the framework on simulated data
and show that it can correctly determine Bayesian credibility intervals on
atmospheric temperatures and abundances allowing for a quantitative exploration
of the inherent degeneracies. Furthermore, our new framework permits us to
trivially combine and explore the synergies between HRCCS and low-resolution
spectroscopy (LRS) to provide maximal leverage on the information contained
within each. This framework also allows us to quantitatively assess the impact
of molecular line opacities at high resolution. We apply the framework to VLT
CRIRES K-band spectra of HD 209458 b and HD 189733 b and retrieve abundant
carbon monoxide but sub-solar abundances for water, largely invariant under
different model assumptions. This confirms previous analysis of these datasets,
but is possibly at odds with detections of water at different wavelengths and
spectral resolutions. The framework presented here is the first step towards a
true synergy between space observatories and ground-based hi-resolution
observations.Comment: Accepted Version (01/16/19
What does really matter in the internationalization of small and medium-sized family businesses?
During the last decades considerable academic attention has been given to the internationalization of family businesses, as it is often considered a way to revitalize both the family and the business. Despite this increasing attention, the debate on its drivers, challenges and constraints is still inconclusive. The aim of this study is to explore whether incoming generationsâ involvement impact the decision to exploit and explore international opportunities and to what extent altruism and competence-based trust mediate that relationship. Three propositions are formulated drawing from international entrepreneurship literature and stewardship theory. To validate this framework, a multiple case study on four Italian family firms has been conducted. The main findings suggest that timing, scope and internationalization modes change in relation to specific family firmsâ features. When âepochalâ changes (e.g. incoming generation) suddenly break down they contribute positively to the exploration and exploitation of international entrepreneurial activities. Moreover, the existence of interpersonal ties based on altruism and competence-based trust between senior and incoming generations mitigates this relationship
Secure Cloud-Edge Deployments, with Trust
Assessing the security level of IoT applications to be deployed to
heterogeneous Cloud-Edge infrastructures operated by different providers is a
non-trivial task. In this article, we present a methodology that permits to
express security requirements for IoT applications, as well as infrastructure
security capabilities, in a simple and declarative manner, and to automatically
obtain an explainable assessment of the security level of the possible
application deployments. The methodology also considers the impact of trust
relations among different stakeholders using or managing Cloud-Edge
infrastructures. A lifelike example is used to showcase the prototyped
implementation of the methodology
The effect of cyber-attacks on stock returns
A widely debated issue in recent years is cybercrime. Breaches in the security of accessibility, integrity and confidentiality of information involve potentially high explicit and implicit costs for firms. This paper investigates the impact of information security breaches on stock returns. Using event-study methodology, the study provides empirical evidence on the effect of announcements of cyber-attacks on the market value of firms from 1995 to 2015. Results show that substantial negative market returns occur following announcements of cyber-attacks. Financial entities often suffer greater negative effects than other companies and non-confidential cyber-attacks are the most dangerous, especially for the financial sector. Overall findings seem to show a link between cybercrime and insider trading
Hermite regularization of the Lattice Boltzmann Method for open source computational aeroacoustics
The lattice Boltzmann method (LBM) is emerging as a powerful engineering tool
for aeroacoustic computations. However, the LBM has been shown to present
accuracy and stability issues in the medium-low Mach number range, that is of
interest for aeroacoustic applications. Several solutions have been proposed
but often are too computationally expensive, do not retain the simplicity and
the advantages typical of the LBM, or are not described well enough to be
usable by the community due to proprietary software policies. We propose to use
an original regularized collision operator, based on the expansion in Hermite
polynomials, that greatly improves the accuracy and stability of the LBM
without altering significantly its algorithm. The regularized LBM can be easily
coupled with both non-reflective boundary conditions and a multi-level grid
strategy, essential ingredients for aeroacoustic simulations. Excellent
agreement was found between our approach and both experimental and numerical
data on two different benchmarks: the laminar, unsteady flow past a 2D cylinder
and the 3D turbulent jet. Finally, most of the aeroacoustic computations with
LBM have been done with commercial softwares, while here the entire theoretical
framework is implemented on top of an open source library (Palabos).Comment: 34 pages, 12 figures, The Journal of the Acoustical Society of
America (in press
Study of inelastic processes in proton-proton collisions at the LHC with the TOTEM experiment
The TOTEM experiment, located into the CMS cavern at the CERN Large Hadron Collider (LHC), is one of the six experiments that are investigating high energy physics at this new machine. In particular TOTEM has been designed for TOTal cross-section, Elastic scattering and diffraction dissociation Measurements. The
total proton-proton cross-section will be measured with the luminosity-independent
method based on the Optical Theorem. This method will allow a precision of 1Ă·2%
at the center of mass energy of 14 TeV. In order to reach such a small error it is necessary to study the p-p elastic scattering cross-section ( dÏ/dt ) down to |t| ⌠10^â3 GeV^2
(to evaluate at best the extrapolation to t = 0) and, at the same time, to measure the total inelastic interaction rate. For this aim, elastically scattered protons must be detected at very small angles with respect to the beam while having the largest possible η coverage for particle detection in order to reduce losses of inelastic events. In addition, TOTEM will also perform studies on elastic scattering with large momentum transfer and a comprehensive physics programme on diffractive processes (partly in cooperation with CMS), in order to have a deeper understanding of the proton structure.
For these purposes TOTEM consists in three different sub-detectors: two gas based telescopes (T1 and T2) for the detection of inelastic processes with a coveragein the range of 3.1 †|η| †6.5 on both sides of the interaction point 5 (IP5), and silicon based detectors for the elastically scattered protons, located in special movable beampipe insertions called Roman Pots (RPs), at about 147 m and 220 m from the interaction point.
The work done by the candidate reported in this thesis mainly consists in three subjects: the tuning of the simulation for the T2 inelastic telescope, the study of the noise of the T2 detector and a preliminary study concerning the detection performance for inelastic events. In the following, the first chapter describes the TOTEM experiment and the LHC machine, with a particular attention to the T2 telescope and its analysis software, being of critical importance for the work of this thesis. The second chapter introduces the physics programme of the TOTEM experiment. Chapter three describes the tuning of Geant4 parameters and the improvement of the simulated geometry for the T2 detector, while chapter four summarizes an important and demanding study on the detector noise. Finally in chapter five some preliminary studies on inelastic processes are presented, in order to show the perspective for the TOTEM experiment to perform the measurement of the inelastic cross section in a wide kinematic range
Towards Run-Time Verification of Compositions in the Web of Things using Complex Event Processing
Following the vision of the Internet of Things, physical world entities are integrated into virtual world things. Things are expected to become active participants in business and social processes. Then, the Internet of Things could benefit from the Web Service architecture like todayâs Web does, so Future ser-vice-oriented Internet things will offer their functionality via service-enabled in-terfaces. In previous work, we demonstrated the need of considering the behav-iour of things to develop applications in a more rigorous way, and we proposed a lightweight model for representing such behaviour. Our methodology relies on the service-oriented paradigm and extends the DPWS profile to specify the order with which things can receive messages. We also proposed a static verifi-cation technique to check whether a mashup of things respects the behaviour, specified at design-time, of the composed things. However, a change in the be-haviour of a thing may cause that some compositions do not fulfill its behaviour anymore. Moreover, given that a thing can receive requests from instances of different mashups at run-time, these requests could violate the behaviour of that thing, even though each mashup fulfills such behaviour, due to the change of state of the thing. To address these issues, we present a proposal based on me-diation techniques and complex event processing to detect and inhibit invalid invocations, so things only receive requests compatible with their behaviour.Work partially supported by projects TIN2008-05932, TIN2012-35669, CSD2007-0004 funded by Spanish Ministry MINECO and FEDER; P11-TIC-7659 funded by Andalusian Government; and Universidad de MĂĄlaga, Campus de Excelencia Internacional AndalucĂa Tec
A framework to combine low- and high-resolution spectroscopy for the atmospheres of transiting exoplanets
Current observations of the atmospheres of close-in exoplanets are
predominantly obtained with two techniques: low-resolution spectroscopy with
space telescopes and high-resolution spectroscopy from the ground. Although the
observables delivered by the two methods are in principle highly complementary,
no attempt has ever been made to combine them, perhaps due to the different
modeling approaches that are typically used in their interpretation. Here we
present the first combined analysis of previously-published dayside spectra of
the exoplanet HD 209458b obtained at low resolution with HST/WFC3 and
Spitzer/IRAC, and at high resolution with VLT/CRIRES. By utilizing a novel
retrieval algorithm capable of computing the joint probability distribution of
low- and high-resolution spectra, we obtain tight constraints on the chemical
composition of the planet's atmosphere. In contrast to the WFC3 data, we do not
confidently detect H2O at high spectral resolution. The retrieved water
abundance from the combined analysis deviates by 1.9 sigma from the
expectations for a solar-composition atmosphere in chemical equilibrium.
Measured relative molecular abundances of CO and H2O strongly favor an
oxygen-rich atmosphere (C/O<1 at 3.5 sigma) for the planet when compared to
equilibrium calculations including O rainout. From the abundances of the seven
molecular species included in this study we constrain the planet metallicity to
0.1-1.0x the stellar value (1 sigma). This study opens the way to coordinated
exoplanet surveys between the flagship ground- and space-based facilities,
which ultimately will be crucial for characterizing potentially-habitable
planets.Comment: 7 pages, 5 figures, accepted for publication in ApJL. Section 4
largely updated from previous version, Figure 2 updated to contain
information on the T-p profil
- âŠ