Search results for "Conti"
showing 10 items of 3486 documents
Introducing Traceability in GitHub for Medical Software Development
2021
Assuring traceability from requirements to implementation is a key element when developing safety critical software systems. Traditionally, this traceability is ensured by a waterfall-like process, where phases follow each other, and tracing between different phases can be managed. However, new software development paradigms, such as continuous software engineering and DevOps, which encourage a steady stream of new features, committed by developers in a seemingly uncontrolled fashion in terms of former phasing, challenge this view. In this paper, we introduce our approach that adds traceability capabilities to GitHub, so that the developers can act like they normally do in GitHub context bu…
Random Walk in a N-cube Without Hamiltonian Cycle to Chaotic Pseudorandom Number Generation: Theoretical and Practical Considerations
2017
Designing a pseudorandom number generator (PRNG) is a difficult and complex task. Many recent works have considered chaotic functions as the basis of built PRNGs: the quality of the output would indeed be an obvious consequence of some chaos properties. However, there is no direct reasoning that goes from chaotic functions to uniform distribution of the output. Moreover, embedding such kind of functions into a PRNG does not necessarily allow to get a chaotic output, which could be required for simulating some chaotic behaviors. In a previous work, some of the authors have proposed the idea of walking into a $\mathsf{N}$-cube where a balanced Hamiltonian cycle has been removed as the basis o…
Dirac equation as a quantum walk over the honeycomb and triangular lattices
2018
A discrete-time Quantum Walk (QW) is essentially an operator driving the evolution of a single particle on the lattice, through local unitaries. Some QWs admit a continuum limit, leading to well-known physics partial differential equations, such as the Dirac equation. We show that these simulation results need not rely on the grid: the Dirac equation in $(2+1)$--dimensions can also be simulated, through local unitaries, on the honeycomb or the triangular lattice. The former is of interest in the study of graphene-like materials. The latter, we argue, opens the door for a generalization of the Dirac equation to arbitrary discrete surfaces.
Continuous design control for machine learning in certified medical systems
2022
AbstractContinuous software engineering has become commonplace in numerous fields. However, in regulating intensive sectors, where additional concerns need to be taken into account, it is often considered difficult to apply continuous development approaches, such as devops. In this paper, we present an approach for using pull requests as design controls, and apply this approach to machine learning in certified medical systems leveraging model cards, a novel technique developed to add explainability to machine learning systems, as a regulatory audit trail. The approach is demonstrated with an industrial system that we have used previously to show how medical systems can be developed in a con…
Towards nonlocal density functionals by explicit modelling of the exchange-correlation hole in inhomogeneous systems
2013
We put forward new approach for the development of a non-local density functional by a direct modeling of the shape of exchange-correlation (xc) hole in inhomogeneous systems. The functional is aimed at giving an accurate xc-energy and an accurate corresponding xc-potential even in difficult near-degeneracy situations such as molecular bond breaking. In particular we demand that: (1) the xc hole properly contains -1 electron, (2) the xc-potential has the asymptotic -1/r behavior outside finite systems and (3) the xc-potential has the correct step structure related to the derivative discontinuities of the xc-energy functional. None of the currently existing functionals satisfies all these re…
Persistence of temperature and precipitation: from local to global anomalies
2021
Using detrended fluctuation analysis (DFA) we find that all continents are persistent in temperature. The scaling exponents of the southern hemisphere (SH) continents, i.e., South America (0.77) and Oceania (0.72) are somewhat higher than scaling exponents of Europe (0.70), Asia (0.69) and North America (0.64), but the scaling of Africa is by far the highest (0.86). The reason for this is the location of Africa near the equator. The scaling exponents of the precipitation are much smaller, i.e. between 0.55 (Europe) and 0.68 (North America). The scaling exponent of Europe is near that of the random noise (0.5), while the other continents are slightly persistent in precipitation. We also show…
Unique continuation of the normal operator of the x-ray transform and applications in geophysics
2020
We show that the normal operator of the X-ray transform in $\mathbb{R}^d$, $d\geq 2$, has a unique continuation property in the class of compactly supported distributions. This immediately implies uniqueness for the X-ray tomography problem with partial data and generalizes some earlier results to higher dimensions. Our proof also gives a unique continuation property for certain Riesz potentials in the space of rapidly decreasing distributions. We present applications to local and global seismology. These include linearized travel time tomography with half-local data and global tomography based on shear wave splitting in a weakly anisotropic elastic medium.
Fabrication of polarizing photonic crystal fibres and photonic crystal fibre tapers: Applications
2007
We report the fabrication of an anisotropic photonic crystal fibre with polarization properties and photonic crystal fibre tapers for supercontinuum generation. The anisotropy of the fibre was created by enlarging four airholes next to the silica core. Different polarization regimes as a function of the geometric parameters, including polarizing behaviour at 1.55 mum, were obtained. In the second part of the paper, we report the fabrication of photonic crystal fibre tapers. We present experimental results on supercontinuum generation in photonic crystal fibre tapers using quasi-continuous pump pulses of 7 ns duration at 532 nm and at 1064 nm.
Rolling or Scrolling? The Effect of Content Type on Habitual Use of Facebook
2020
The paper investigates how content type (i.e., hedonic and utilitarian content) is related to satisfaction, habitual use, use intensity and discontinued use intentions in the context of social media services. The research model was empirically tested using a survey study (n = 142) that was conducted among Facebook users. The results show that hedonic content is a strong predictor of habitual use of and satisfaction with Facebook. In turn, utilitarian content has a positive effect on satisfaction; however, it does not significantly affect habitual use. Additionally, habit affects use intensity more than satisfaction but has no significant effect on discontinued use intention. These results s…
The Influence of Strategic and Organizational Factors as Concern the Relationship between Environmental Management Control and Organizational Learnin…
2020
This article examines the relationship between Environmental Management Control (EMC) and Organizational Learning (OL) by extending the theoretical model of Simons (1995) in a contingent perspective. Through strategic and organizational factors, this enriched model expounds the links between the Simons’s (1995) levers of control (diagnostic and interactive controls) and the Argyris and Schön’s (1978) levels of learning (simple loop learning and double loop learning). Based on the “revelatory case” of a missionary organization, eco-SME, this study highlights the influence of three contingency factors : strong core values, proactive strategy and activity life cycle in the four configurations …