Miracle-dz/UniFAR-FTUs huggingface dataset:
Semi‐global finite‐time observers for multi‐output nonlinear systems

Finite‐time stability is investigated for nonlinear systems, which satisfy uniqueness of solution. First, a new sufficient condition for local finite‐time stability is presented. Next, by using the high‐gain observers and carefully selecting the homogeneity powers and weights, the problem of semi‐global and finite‐time stable observers is studied for multi‐output nonlinear systems with uniform observability and a triangular structure. Then, a design procedure is worked out for such observers. Finally, two numerical examples further verify the validity of the proposed approach. Copyright © 2009 John Wiley & Sons, Ltd.
Time-resolved characterization of external-cavity quantum-cascade lasers

We report on the temporal and spectral evolution of the lasing spectrum of an external-cavity quantum-cascade (QC) laser operated in pulsed mode. Time-resolved lasing spectra, recorded on nanosecond time scale, revealed that after turn-on of the 100 ns current pulse multiple-mode lasing starts at the gain maximum of the QC laser controlled by the cavity formed by the chip facets. Depending on the spectral tuning after a time delay of 15–35 ns, the QC laser couples to the external cavity as seen from a change in lasing wavelength to that defined by the external grating as wavelength selective element.
Estimates of Turbulence from Numerical Weather Prediction Model Output with Applications to Turbulence Diagnosis and Data Assimilation

Abstract Estimates of small-scale turbulence from numerical model output are produced from local estimates of the spatial structure functions of model variables such as the velocity and temperature. The key assumptions used are the existence of a universal statistical description of small-scale turbulence and a locally universal spatial filter for the model variables. Under these assumptions, spatial structure functions of the model variables can be related to the structure functions of the corresponding atmospheric variables. The shape of the model spatial filter is determined by comparisons with the spatial structure functions from aircraft data collected at cruising altitudes. This universal filter is used to estimate the magnitude of the small-scale turbulence, that is, scales smaller than the filter scale. A simple yet universal description of the basic statistics (such as the probability density function and the spatial correlation) of these small-scale turbulence levels in the upper troposphere and.
Some Results on Optimal Reinsurance in Terms of the Adjustment Coefficient

Abstract A direct insurer wants to reinsure a certain part of a risk treaty. An underwriter who has been offered a reinsurance contract will rate the contract according to some premium principle. Depending on which premium principle the underwriter applies, the cedent will seek the type of reinsurance cover which gives him the best risk protection at a certain price. The paper is concerned with optimal reinsurance structures when the ceding insurer, and the reinsurer, seek to minimize the probability of eventual ruin. The cedent's, and reinsurer's, optimal choice of reinsurance is derived for various premium principles. Also the ‘Pareto optimal’ reinsurance structure is determined.
Virgo: a laser interferometer to detect gravitational waves

This paper presents a complete description of Virgo, the French-Italian gravitational wave detector. The detector, built at Cascina, near Pisa (Italy), is a very large Michelson interferometer, with 3 km-long arms. In this paper, following a presentation of the physics requirements, leading to the specifications for the construction of the detector, a detailed description of all its different elements is given. These include civil engineering infrastructures, a huge ultra-high vacuum (UHV) chamber (about 6000 cubic metres), all of the optical components, including high quality mirrors and their seismic isolating suspensions, all of the electronics required to control the interferometer and for signal detection. The expected performances of these different elements are given, leading to an overall sensitivity curve as a function of the incoming gravitational wave frequency. This description represents the detector as built and used in the first data-taking runs. Improvements in different parts have been and continue to be performed, leading to better sensitivities. These will be detailed in a forthcoming paper.
Emerging Role of Plant-Based Dietary Components in Post-Translational Modifications Associated with Colorectal Cancer

Colorectal cancer (CRC) is one of the most common cancers worldwide. Its main modifiable risk factors are diet, alcohol consumption, and smoking. Thus, the right approach through lifestyle changes may lead to its prevention. In fact, some natural dietary components have exhibited chemopreventive activity through modulation of cellular processes involved in CRC development. Although cancer is a multi-factorial process, the study of post-translational modifications (PTMs) of proteins associated with CRC has recently gained interest, as inappropriate modification is closely related to the activation of cell signalling pathways involved in carcinogenesis. Therefore, this review aimed to collect the main PTMs associated with CRC, analyse the relationship between different proteins that are susceptible to inappropriate PTMs, and review the available scientific literature on the role of plant-based dietary compounds in modulating CRC-associated PTMs. In summary, this review suggested that some plant-based dietary components such as phenols, flavonoids, lignans, terpenoids, and alkaloids may be able to correct the inappropriate PTMs associated with CRC and promote apoptosis in tumour cells.
Numerical Analysis of a Single Rising Bubble Using Boundary-Fitted Coordinate System

A numerical method is developed to simulate unsteady axisymmetric flow with a free surface. The method is based on a finite-volume solution of the equations on an orthogonal curvilinear coordinate system. A new iteration technique is used for the boundary condition of the free surface in order to stabilize the solution. The numerical method is applied to the simulation of unsteady motion of a single deformed bubble rising through a quiescent liquid. The numerical results show good quantitative agreement with those of experiments and calculations reported previously by other researchers. In the present study, the transient phenomena of an initially spherical bubble as it reaches the steady state are investigated. It is known experimentally that the rising bubble begins to show an unsteady three-dimensional(spiral or zigzag)motion beyond certain critical Reynolds and Weber numbers. Our numerical results suggest that the growth of axisymmetric shape oscillation causes three-dimensional motions of a rising bubble.
Large-Scale Cultivation of Magnetotactic Bacteria and the Optimism for Sustainable and Cheap Approaches in Nanotechnology

Magnetotactic bacteria (MTB), a diverse group of marine and freshwater microorganisms, have attracted the scientific community’s attention since their discovery. These bacteria biomineralize ferrimagnetic nanocrystals, the magnetosomes, or biological magnetic nanoparticles (BMNs), in a single or multiple chain(s) within the cell. As a result, cells experience an optimized magnetic dipolar moment responsible for a passive alignment along the lines of the geomagnetic field. Advances in MTB cultivation and BMN isolation have contributed to the expansion of the biotechnological potential of MTB in recent decades. Several studies with mass-cultured MTB expanded the possibilities of using purified nanocrystals and whole cells in nano- and biotechnology. Freshwater MTB were primarily investigated in scaling up processes for the production of BMNs. However, marine MTB have the potential to overcome freshwater species applications due to the putative high efficiency of their BMNs in capturing molecules. Regarding the use of MTB or BMNs in different approaches, the application of BMNs in biomedicine remains the focus of most studies, but their application is not restricted to this field. In recent years, environment monitoring and recovery, engineering applications, wastewater treatment, and industrial processes have benefited from MTB-based biotechnologies. This review explores the advances in MTB large-scale cultivation and the consequent development of innovative tools or processes.
Diffraction of an E-polarized plane wave by an imperfectly conducting wedge

A new and exact solution is obtained for the diffraction of an E-polarized electromagnetic plane wave by an imperfectly conducting wedge of arbitrary angle. The original boundaryvalue problem is reduced to the solution of an ordinary difference equation. This equation is solved in terms of the double gamma function defined by Barnes (1899). If the wedge angle is equal to pπ/2q where p and q are relatively prime integers, with p odd, the difference equation is soluble in a simple closed form. The resulting solution for the field components is then comparatively simple. The present theoretical results show very good agreement with experimental results in the shadow region for normal incidence on a 16° wedge.
LOCAL SOLVABILITY OF AN INITIAL BOUNDARY VALUE PROBLEM FOR A QUASILINEAR HYPERBOLIC-PARABOLIC SYSTEM

This paper investigates the solvability of initial boundary value problem for a quasilinear hyperbolic-parabolic system which consists of a transport equation and strongly parabolic system. The characteristics of the transport equation are assumed to be outward on the boundary of the domain. The unique local (in time) existence of solutions is shown in the class of continuous functions with values in Hs, where s is an integer satisfying s ≥ [n/2]+1.
Modeling and performance assessment of an isolated wind-diesel system with flywheel energy storage system

This paper proposes incorporation of a flywheel energy storage system (FESS) into hybrid wind-diesel power plant for system frequency and voltage response improvement. The impact of hybrid wind-diesel energy storage systems under various forms of disturbances, such as load disturbance, wind disturbance, wind park disconnection, and step variations in wind is presented and analyzed. The standard IEEE models for different components of hybrid wind diesel power system are considered. Simulations in the time domain are carried out in order to test the performance of proposed system. The positive impact of FESS used in wind-diesel hybrid power system is demonstrated through a series of simulation cases carried for various types of disturbances.
Noyaux multiples : sélection de modèle appliquée à la détection de piéton

This paper presents a pedestrian detection method based on the multiple kernel framework. One main problematic of pattern recognition resides in the pertinent characterization of the data. Depending on the descriptor, we sometimes have to tune the descriptor in order to be more efficient. Instead of accomplishing this tuning manually by testing and comparing all possible values we propose here to use the multiple kernel framework. The aim is to use a kernel as a linear combination of different kernels in order to combine and select automatically the best kernels within a set of kernels. This can be assimilated as model selection, where one kernel of the set corresponds to one model. We first introduce the MKL framework and finally apply this approach for a parameter tuning task and a feature selection problem.
ZnO nanostructure synthesis for the photocatalytic degradation of azo dye methyl orange from aqueous solutions utilizing activated carbon

In this study, zinc acetate (as a precursor) and activated carbon carboxylic acid derivative were used to create the nanostructure of zinc oxide (ZnO) as a matrix. The carboxylic acid derivative was produced by modifying the oxidized activated carbon with nitric acid (AC-COOH). The modified activated carbon's surface was then impregnated with zinc to load it. By using BET, XRD, and SEM to characterize the ZnO nanostructure, it was discovered that it was composed of nanoparticles with a surface area capacity of 17.78 m2 g-1 and a size range of 21–31 nm. The photocatalytic hydrolysis of the dye methyl orange in an aqueous medium served as a test case for the catalyst's performance. The primary variables were considered, including pH, catalyst dose, stirring effect, and starting dye concentration. Measurements of activity below UV light revealed satisfactory outcomes for photocatalytic hydrolysis of the methyl orange (MO). In addition, the efficiency of the methyl orange (MO) photolysis catalyst prepared with unmodified activated carbon was also evaluated. The outcomes proved that zinc oxide (ZnO), made using a derivative carboxylic acid of activated carbon molecules by a matrix, had more good photocatalytic action than zinc oxide (ZnO) made by the real activated carbon matrix.
Interference effects in new physics processes at the LHC

Interference effects between nearly mass-degenerate particles are ad- dressed in this thesis, comprising higher-order calculations, a model- independent method to calculate interference terms efficiently and a phenomenological application to current Higgs searches at the LHC. Predictions of cross sections and decay widths can be severely affected by interference terms between quasi-degenerate states arising in models beyond the Standard Model. We formulate a generalisation of the narrow-width approximation (NWA) which allows for a consistent treatment of such effects by factorising the interference term into on-shell matrix elements of the production and decay parts, optionally further approximated as simple interference weight factors, incorporating one- loop and real corrections in a UV- and IR-finite way(.)
Study of Multilayer Ceramic Photonic Crystals in THz Region

We have fabricated one-dimensional photonic crystals with a conventional ceramic layering process and investigated their terahertz wave transmission properties by terahertz time-domain spectroscopy (THz-TDS). In one-dimensional photonic crystals with a structural defect, a narrow transmission band (i.e., a defect mode) appears within the band gap. However, the dielectric losses of the ceramic materials significantly suppress the transmission intensity of the defect mode. The observed low transmission is mainly associated with the absorption loss of the defect layer material. Since the internal multiple reflections enhance the absorption loss, tuning the periodicity of the photonic crystal from a high reflectivity condition is effective for improving the transmission intensity of the defect mode. The measured highest peak transmission is -4.5 dB when periodicity is changed from a quarter-wavelength stack.
NGC 2309: A Relatively Young Open Cluster Projected onto a Random Stellar Concentration

We have obtained CCD UBVIKC photometry down to V ∼ 22.0 for the open cluster NGC 2309 and its surrounding field. Twenty three probable cluster members have been identified for the first time on the basis of sound photometric criteria. Because NGC 2309 is a relatively poor cluster projected onto a rich star field showing density fluctuations, the frequently used membership criteria based on stellar density profiles or proper motion measurements would not be enough to assess the star membership status if employed independently. We estimated a cluster radius of 7.9′ and a radius at half the maximum of the cluster density profile of 1.7′. Based on the best fits of isochrones computed by the Geneva group to the cluster color–magnitude and color–color diagrams, previously shifted by the cluster reddening (E(B - V) = 0.32) and distance (d = 2.5 kpc), we derived the cluster age (250 Myr) and metallicity ([Fe/H] ≃ 0.0). If an 8.5 kpc distance from the Sun to the center of the Galaxy is assumed, then NGC 2309 is found to be located just in front of the Perseus spiral arm.
Current status of self-organized epitaxial graphene ribbons on the C face of 6H–SiC substrates

The current status of long, self-organized, epitaxial graphene ribbons grown on the (0 0 0 −1) face of 6H–SiC substrates is reviewed. First, starting from the early stage of growth it is shown that on the C face of 6H–SiC substrates the sublimation process is not homogeneous. Most of the time it starts from defective sites, dislocations or point defects, that define nearly circular flakes surrounded by bare SiC. These flakes have a volcano-like shape with a graphite chimney at the centre, where the original defect was located. At higher temperatures a complete conversion occurs, which is not yet homogeneous on the whole sample. This growth process can be modified by covering the sample with a graphite cap. It changes the physics of the surface reconstruction during the Si-sublimation process and, on the C face, makes more efficient the reconstruction of few selected terraces with respect to the others. The net result is the formation of strongly step-bunched areas with, in between, long and large reconstructed terraces covered by graphitic material. Despite the low intrinsic optical absorption of a few graphene layers on SiC, micro-transmission experiments, complemented by micro-Raman spectroscopy, demonstrate that most of this graphitic coverage is made of one or two homogeneous graphene layers. We show also that most of the thermal stress between the graphene layer and the 6H–SiC substrate is relaxed by pleats or wrinkles which are clearly visible on the AFM images. Finally, the results of transport experiments performed on the graphitic ribbons reveal the p-type character of the ribbons.
The Fefferman metric and pseudo-Hermitian invariants

C. Fefferman has shown that a real strictly pseudoconvex hypersurface in complex n-space carries a natural conformai Lorentz metric on a circle bundle over the manifold. This paper presents two intrinsic constructions of the metric, valid on an abstract CR manifold. One is in terms of tautologous differential forms on a natural circle bundle; the other is in terms of Webster's pseudohermitian invariants. These results are applied to compute the connection and curvature forms of the Fefferman metric explicitly.
Enumeration, orthogonality and completeness of the incompressible Coriolis modes in a sphere

Abstract We consider incompressible flows in the rapid-rotation limit of small Rossby number and vanishing Ekman number, in a bounded volume with a rigid impenetrable rotating boundary. Physically the flows are inviscid, almost rigid rotations. We interpret the Coriolis force, modified by a pressure gradient, as a linear operator acting on smooth inviscid incompressible flows in the volume. The eigenfunctions of the Coriolis operator $\boldsymbol{{\mathcal{C}}}$ so defined are the inertial modes (including any Rossby modes) and geostrophic modes of the rotating volume. We show $\boldsymbol{{\mathcal{C}}}$ is a bounded operator and that $-\text{i}\boldsymbol{{\mathcal{C}}}$ is symmetric, so that the Coriolis modes of different frequencies are orthogonal. We prove that the space of incompressible polynomial flows of degree $N$ or less in a sphere is invariant under $\boldsymbol{{\mathcal{C}}}$ . The symmetry of $-\text{i}\boldsymbol{{\mathcal{C}}}$ thus implies the Coriolis operator is non-defective on the finite-dimensional space of spherical polynomial flows. This enables us to enumerate the Coriolis modes, and to establish their completeness using the Weierstrass polynomial approximation theorem. The fundamental tool, which is required to establish invariance of spherical polynomial flows under $\boldsymbol{{\mathcal{C}}}$ and completeness, is that the solution of the polynomial Poisson–Neumann problem, i.e. Poisson’s equation with a Neumann boundary condition and polynomial data, in a sphere is a polynomial. We also enumerate the Coriolis modes in a sphere, with careful consideration of the geostrophic modes, directly from the known analytic solutions.
Asymptotic solutions for nonlinear magnetoconvection

Convection in a vertical magnetic field occurs in narrow cells in the physically relevant limit where the Chandrasekhar number Q becomes large, corresponding to a strong field or small diffusion. This allows asymptotic solutions to be developed for fully nonlinear convection, requiring only the solution of a nonlinear boundary value problem. Solutions for steady and oscillatory magnetoconvection are obtained, with different scalings. In the steady case, the heat flux and the fluid velocity are found at leading order in the asymptotic expansion and the vertical velocity scales as Q1/6. In the oscillatory case, where it is necessary to continue to second order, the vertical velocity is of order Q1/3 and the frequency of the oscillations is always greater than that predicted by linear theory. The heat flux does not depend on either the wavenumber or the planform.
A Link between the Hβ Equivalent Width, Profile Width, BLR Size, and Optical Luminosity from a Small Sample of Well-studied Active Galactic Nuclei

We present diagrams of the relationship between the broad Hβ emission-line parameters and the continuum luminosity obtained from a sample of 31 well-studied Seyfert 1.0–1.5 galaxies and quasars. The equivalent width of the Hβ line is inversely correlated with the continuum luminosity at 5100 Å as EW ∼ L, which seems to be comparable to that obtained by other authors for the Lyα. So, we have detected, although very marginally, a Baldwin effect in the Hβ line. The remarkably small scattering of the Hβ equivalent widths probably indicates approximately the same spectral energy distribution from optics to ionizing radiation, nearly the same covering factor, and nearly isotropic continuum emission, although some of these agents can show small systematic changes with luminosity. The intrinsic Baldwin effect for the Hβ is clearly seen only in NGC 5548. Considering the observed lag-luminosity and lag–line-width dependences we suppose that it might be caused by full ionization of clouds. We compute the linear regression parameters (the slopes and intercepts) of the relationship between the Hβ and optical continuum fluxes. In some cases, the regression parameters derived from the homogeneous data sets are significantly different for different observational periods. The lag of the Hβ response to continuum variations shows a strong correlation with the luminosity. Combining the regression results on time delay and rms widths of the Hβ line, we obtained the following mass-luminosity relationship for AGNs: L ∝ M1.9±1.1.
Academic career progression from early career researcher to professor: what can we learn from job ads

ABSTRACT Academic careers are complex, diverse, and increasingly competitive. Building on previous research on selection criteria for admission to early research careers, this research expands the analytical focus to examine attributes requested in job ads at each stage of an academic career. Our data, extracted from a European job platform, draws on over 40 different disciplines, 3000 universities, and 60 countries. We developed a taxonomy from the selection criteria data and analysed 40,819 advertisements for all stages combined and posted in 2016-2021. We analysed the most prevalent and salient attributes listed in academic job ads to determine the most important attributes in the five most represented countries and disciplines, and changes by stage and across the academic career lifespan. We find that degree and achievements play a principal role in academic recruitment at each stage of career, mobility is key to progression in senior roles, teaching gains importance towards professoriate, and senior academics need to be equipped with skills and/or experience in fundraising, curriculum, and outreach. The insights inform policy and practice for institutional researcher development, capabilities framework development, human resources, and academic recruitment, and provide guidance for academic career planning and development.