Miracle-dz/UniFAR-FTUs huggingface dataset:
Anaphore Associative, Pontage et Stéréotypie

One of the central questions that any description of associative anaphor (Nous arrivâmes dans un village. L'eglise etait situee sur une hauteur) implies is that of the role which stereotypic knowledge plays in its establishment. There are two conflicting answers. One maintains that the associative relation is of semantic or a priori order. The other, on the contrary, asserts that cognition and discourse are responsible for such anaphoric connections. The aim of this paper is to show that, despite their attractive power, the arguments and examples invoked by the second one, are not sufficient to finally carry the day: associative anaphors works with stereotyps.
Mechanisms of complex morphological evolution during solid-state dewetting of single-crystal nickel thin films

We report studies of complex morphological evolution during solid-state dewetting of 120 nm thick single-crystal Ni(100) and Ni(110) thin films on MgO(100) and MgO(110) substrates. During dewetting, holes that form in the Ni films evolve to complex shapes that depend on the crystallographic orientation of the films and annealing ambient. We characterize the origins of hole, line, and particle morphologies that develop during the dewetting process, and identify a sequence of instabilities that control the morphological evolution. This study provides mechanistic insights for control of dewetting to produce specific ordered structures.
Effects of non-orthogonality and electron correlations on the time-dependent current through quantum dots

The concept of the transfer Hamiltonian formalism has been reconsidered and generalized to include the non-orthogonality between the electron states in an interacting region, e.g. quantum dot (QD), and the states in the conduction bands in the attached contacts. The electron correlations in the QD are described by means of a diagram technique for Hubbard operator Green functions for non-equilibrium states. It is shown that the non-orthogonality between the electrons states in the contacts and the QD is reflected in the anti-commutation relations for the field operators of the subsystems. The derived forumla for the current contains corrections from the overlap of the same order as the widely used conventional tunneling coefficients. It is also shown that kinematic interactions between the QD states and the electrons in the contacts, renormalizes the QD energies in a spin-dependent fashion. The structure of the renormalization provides an opportunity to include a spin splitting of the QD levels by polarizing the conduction bands in the contacts and/or imposing different hybridizations between the states in the contacts and the QD for the two spin channels. This leads to a substantial amplification of the spin polarization in the current, suggesting applications in magnetic sensors and spin-filters.
Correlations and one-quantum pulse shapes in photon pair generation

Abstract We examine the correlation between a pair of photons in the information entropy context. Either in two-photon cascade decay of a three-level system or in parametric down-conversion a pure state of two distinguishable photons is produced, with the states of the individual photons entangled. We obtain state amplitudes in the Weisskopf-Wigner approximation and use them to derive the two-photon density matrix in the ‘arrival time’ basis. It is found that only a finite number of eigenvectors of the appropriate density matrices is required to describe the system. That is, despite the continua of wave-vectors involved in the double spontaneous decay the two-photon entanglement is effectively discrete; furthermore, the eigenvectors in the arrival time basis can be interpreted as the fundamental orthogonal spontaneous emission pulses of the two systems.
Observational signatures of atmospheric velocity fields in Main Sequence stars

In stars with sufficiently small projected rotational velocities (less than a few ${\rm km\,s}^{-1}$), it is often possible to detect signatures of the atmospheric velocity field in line profiles. These signatures may be as subtle as small asymmetries in the profile (“line bisector curvature”) or as obvious as profile shapes that strongly depart from those predicted by simple microturbulence models. We have recently carried out a high resolution survey of sharp-line stars to search for these symptoms of local velocity fields. We report the first results of a comparison of models with the observed profiles.To search for other articles by the author(s) go to: http://adsabs.harvard. edu/abstract_service. html
Effect of Non-uniform Temperature gradient on Marangoni Convection in a Relatively Hotter or Cooler Layer of Liquid

The effect of non-uniform temperature gradient on the onset of convection driven by surface tension gradients in a relatively hotter or cooler layer of liquid is studied by means of linear stability analysis. The upper boundary is considered to be free where surface tension gradients arise on account of variation in temperature and the lower boundary is stress free, each subject to constant heat flux. The single-term Galerkin technique is used to obtain the eigenvalue equation. Eigenvalues are obtained and presented. The results are compared with the existing ones and found that even a single-term Galerkin expansion gives quite accurate results. Further, this analysis predicts that the critical eigenvalues for different non-uniform temperature gradients are greater in a relatively hotter layer of liquid than the cooler one under identical conditions otherwise. This qualitative effect is quite significant quantitatively as well.
Maximum signal energy concentration in a time-frequency domain

An approach which operates directly in the time-frequency plane is proposed to address the problem of finding the signal whose time-frequency energy distribution is most concentrated in a given time-frequency domain of any shape. The solution is shown to be that of an eigenequation depending on both the considered domain and the chosen distribution. Explicit solutions are derived for elliptic domains in the Wigner-Ville case, and connections with classical approaches are pointed out. <<ETX>>
Does the Newton's gravitational constant vary sinusoidally with time? An independent test with planetary orbital motions

A sinusoidally time-varying pattern for the values of the Newton's constant of gravitation $G$ measured in Earth-based laboratories over the latest decades has been recently reported in the literature. Its amplitude and period amount to $A_G=1.619\times 10^{-14} \textrm{kg}^{-1} \textrm{m}^3 \textrm{s}^{-2}, P_G=5.899 \textrm{yr}$, respectively. Given the fundamental role played by $G$ in the currently accepted theory of gravitation and the attempts to merge it with quantum mechanics, it is important to put to the test the hypothesis that the aforementioned harmonic variation may pertain $G$ itself in a direct and independent way. The bounds on $\dot G/G$ existing in the literature may not be extended straightforwardly to the present case since they were inferred by considering just secular variations. Thus, we numerically integrated the ad-hoc modified equations of motion of the major bodies of the Solar System by finding that the orbits of the planets would be altered by an unacceptably larger amount in view of the present-day high accuracy astrometric measurements. In the case of Saturn, its geocentric right ascension $\alpha$, declination $\delta$ and range $\rho$ would be affected up to $10^4-10^5$ milliarcseconds and $10^5$ km, respectively; the present-day residuals of such observables are as little as about $4$ milliarcseconds and $10^{-1}$ km, respectively.
A Midlatitude Cirrus Cloud Climatology from the Facility for Atmospheric Remote Sensing. Part III: Radiative Properties

Abstract In Part III of a series of papers describing the extended time high-cloud observations from the University of Utah Facility for Atmospheric Remote Sensing (FARS) supporting the First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment, the visible and infrared radiative properties of cirrus clouds over Salt Lake City, Utah, are examined. Using ∼860 h of combined ruby (0.694 μm) lidar and midinfrared (9.5–11.5 μm) radiometer data collected between 1992 and 1999 from visually identified cirrus clouds, the visible optical depths τ and infrared layer emittance ϵ of the varieties of midlatitude cirrus are characterized. The mean and median values for the cirrus sample are 0.75 ± 0.91 and 0.61 for τ, and 0.30 ± 0.22 and 0.25 for ϵ. Other scattering parameters studied are the visible extinction and infrared absorption coefficients, and their ratio, and the lidar backscatter-to-extinction ratio, which has a mean value of 0.041 sr−1. Differences among cirrus clouds generated by g.
A design study of mirror modules and an assembly based on the slumped glass for an Athena-like optics

The Athena mission was selected for the second large-class mission, due for launch in 2028, in ESA’s Cosmic Vision program. The current solution for the optics is based on the Silicon Pore Optics (SPO) technology with the goal of 2m2 effective area at 1keV (aperture about 3m diameter) with a focal length of 12m. The SPO advantages are the compactness along the axial direction and the high conductivity of the Silicon. Recent development in the fabrication of mirror shells based on the Slumped Glass Optics (SGO) makes this technology an attractive solution for the mirror modules for Athena or similar telescopes. The SGO advantages are a potential high collecting area with a limited vignetting due to the lower shadowing and the aptitude to curve the glass plates up to small radius of curvature. This study shows an alternative mirror design based on SGO technology, tailored for Athena needs. The main challenges are the optimization of the manufacturing technology with respect to the required accuracy and the thermal control of the large surface in conjunction with the low conductivity of the glass. A concept has been elaborated which considers the specific benefits of the SGO technology and provides an efficient thermal control. The output of the study is a preliminary design substantiated by analyses and technological studies. The study proposes interfaces and predicts performances and budgets. It describes also how such a mirror system could be implemented as a modular assembly for X-ray telescope with a large collecting area.
Magnon excitation by spin-polarized direct currents in magnetic nanostructures

The dynamics of the magnetization in a thin ferromagnetic film traversed by a spin-polarized direct current is studied. In such a system, spin waves (magnons) may be critically driven out of equilibrium by an effective spin-injection field that is proportional to the current density. A direct comparison between the predicted critical current and previous experimental results sheds light on the nature of the excited mode. Beyond the threshold, it is assumed that the spin waves are coupled through nonlinear interactions arising from dipolar and surface anisotropy energies. It is shown that the magnon-magnon interactions play two major roles in the dynamics: (i) They govern and put a limit to the growth in the population of the unstable mode from the thermal level, and (ii) directly contribute to the renormalization of the magnon energy, which manifests itself through a shift in the precession frequency of the magnetic moments with varying current intensity. Numerical results are presented in remarkable quantitative agreement with recent experiments in nanometric magnetic multilayers, where microwave oscillations generated by direct currents have been observed in the postthreshold regime.
64 Orionis: Three-Dimensional Orbit and Physical Parameters

We have obtained radial velocities of the components of the short-period subsystem of the B-type triple star 64 Orionis, covering a full cycle of the long-period orbit since the date of our earlier paper by Fekel & Scarfe. We use all of our radial velocities, together with available speckle interferometry, to derive a three-dimensional orbit for the long-period system. The system has orbital periods of 14.57213 days and 12.98 yr. We also determine spectroscopically a magnitude difference at 4500 Å of 1.0 ± 0.1 between the components of the close pair. Although radial velocities of the third component continue to elude us, we are able to derive masses and luminosities for all three components by requiring that they lie within the populated band of the observed mass-luminosity relationship. With this constraint, the orbital parallax is 0. ″00374 ± 0. ″00017. Our results are consistent with the spectral types and colors derived previously and with the b magnitude difference determined by earlier lunar occultation observations, within the uncertainties of those parameters.
High-precision characterization of textured a-Si:H/SnO2:F structures by spectroscopic ellipsometry

Spectroscopic ellipsometry (SE) has been applied for the characterization of hydrogenated amorphous silicon (a-Si:H) layers formed on SnO2:F textured structures in an attempt to establish the structural characterization method for a-Si:H solar cells. In particular, an optical model that allows the complete evaluation of microscopically non-uniform a-Si:H/SnO2:F textured structures has been developed for the SE analysis. In order to express the complicated optical response in the textured structures, the optical model incorporates (i) the surface roughness and interface layers calculated using an effective-medium-approximation multilayer model and (ii) the a-Si:H/SnO2:F structure divided into two regions with different thicknesses. Using this optical model, SE spectra obtained experimentally from the a-Si:H/SnO2:F textured structure can be reproduced almost perfectly. The a-Si:H/SnO2:F structure deduced from the SE analysis shows remarkable agreement with that observed from transmission electron microscopy. Moreover, a variety of a-Si:H layers with different thicknesses are expressed from the identical optical model. The SE analysis method developed in this study can be utilized further to perform high-precision and non-destructive characterization of various a-Si:H layers incorporated in large-area a-Si:H modules.
Computing and Graphing Highest Density Regions

Abstract Many statistical methods involve summarizing a probability distribution by a region of the sample space covering a specified probability. One method of selecting such a region is to require it to contain points of relatively high density. Highest density regions are particularly useful for displaying multimodal distributions and, in such cases, may consist of several disjoint subsets—one for each local mode. In this paper, I propose a simple method for computing a highest density region from any given (possibly multivariate) density f(x) that is bounded and continuous in x. Several examples of the use of highest density regions in statistical graphics are also given. A new form of boxplot is proposed based on highest density regions; versions in one and two dimensions are given. Highest density regions in higher dimensions are also discussed and plotted.
Compound random mappings

In this paper, we introduce a compound random mapping model which can be viewed as a generalization of the basic random mapping model considered by Ross and by Jaworski. We investigate a particular example, the Poisson compound random mapping, and compare results for this model with results known for the well-studied uniform random mapping model. We show that, although the structure of the components of the random digraph associated with a Poisson compound mapping differs from the structure of the components of the random digraph associated with the uniform model, the limiting distribution of the normalized order statistics for the sizes of the components is the same as in the uniform case, i.e. the limiting distribution is the Poisson-Dirichlet (½) distribution on the simplex {{x i } : ∑ x i ≤ 1, x i ≥ x i+1 ≥ 0 for every i ≥ 1}.
Bounds on the transport and optical properties of a two‐component composite material

An infinite set of bounds on the effective permittivity ee of two‐component composite materials is derived. All the bounds can be expressed in terms of a single function g. Analogous bounds apply to the other transport properties of the composite, such as the thermal and electrical conductivities and the magnetic permeability. The work also applies to the optical properties of the composite, provided the wavelength is sufficiently large compared with the structure of the composite. In all cases we find ee is confined to a region of the complex plane bounded by arcs of circles. The appropriate region is determined by what is known about the composite and as more information is known the region becomes progressively smaller. We show that in many cases the region is the most restrictive which can be found using only the known information about the composite material.
The role of growth atmosphere on the structural and optical quality of defect free ZnO films for strong ultraviolet emission

Highly c-axis oriented wurtzite structured ZnO thin films were deposited on silicon substrates using pulsed laser deposition (PLD) by ablating a ZnO target in different atmospheres, including vacuum, argon and oxygen in the deposition chamber. The stress in the films was shown to vary from −3.83 to −0.03 GPa as a function of the chamber atmosphere. The minimum compressive stress (−0.03 GPa) was observed for the oxygen atmosphere. X-ray photoelectron spectroscopy data indicated that the O1s peak consists of three components designated as O1 (due to ZnO), O2 (due to defects) and O3 (due to adsorbed species). A small defect level emission was obtained in the luminescence spectra of the ZnO film deposited in the oxygen atmosphere, while strong ultraviolet (UV) emission was observed for the ZnO films deposited in the vacuum and argon atmosphere. These PLD grown ZnO thin films have the potential to be used as sources of UV radiation in light emitting devices.
Examples of pleating varieties for twice punctured tori

We give an explicit description of some pleating varieties (sets with a fixed set of bending lines in the convex hull boundary) in the quasi-Fuchsian space of the twice punctured torus. In accordance with a conjecture of the second author, we show that their closures intersect Fuchsian space in the simplices of minima introduced by Kerckhoff. All computations are done using complex Fenchel-Nielsen coordinates for quasi-Fuchsian space referred to a maximal system of curves.
Thermodynamics of Cu47Ti34Zr11Ni8, Zr52.5Cu17.9Ni14.6Al10Ti5 and Zr57Cu15.4Ni12.6Al10Nb5 bulk metallic glass forming alloys

The differences in the thermodynamic functions between the liquid and the crystalline states of three bulk metallic glass forming alloys, Cu47Ti34Zr11Ni8, Zr52.5Cu17. 9Ni14.6Al10Ti5, and Zr57Cu15.4Ni12. 6Al10Nb5, were calculated. The heat capacity was measured in the crystalline solid, the amorphous solid, the supercooled liquid, and the equilibrium liquid. Using these heat capacity data and the heats of fusion of the alloys, the differences in the thermodynamic functions between the liquid and the crystalline states were determined. The Gibbs free energy difference between the liquid and the crystalline states gives a qualitative measure of the glass forming ability of these alloys. Using the derived entropy difference, the Kauzmann temperatures for these alloys were determined.
A COMPARATIVE STUDY OF BAYESIAN AND MAXIMUM LIKELIHOOD APPROACHES FOR ARCH MODELS WITH EVIDENCE FROM BRAZILIAN FINANCIAL SERIES

The purpose of this study is to address the inference problem of the parameters of autoregressive conditional heteroscedasticity (ARCH) models. Specifically, we present a comparison of the two approaches — Bayesian and Maximum Likelihood (ML) for ARCH models, and the specific mathematical and algorithmic formulations of these approaches. In the ML, estimation we obtain confidence intervals by using the Bootstrap simulation technique. In the Bayesian estimation, we present a reparametrization of the model which allows us to apply prior normal densities to the transformed parameters. The posterior estimates are obtained using Monte Carlo Markov Chain (MCMC) methods. The methodology is exemplified by considering two Brazilian financial time series: the Bovespa Stock Index — IBovespa and the Telebras series. The order of each ARCH model is selected by using the Bayesian Information Criterion (BIC).
Local Parallel Models For Integration Of Stereo Matching Constraints And Intrinsic Image Combination

Parallel relaxation computations such as those of connectionist networks offer a useful model for constraint integration and intrinsic image combination in developing a general-purpose stereo matching algorithm. This paper describes such a stereo algorithm that incorporates hierarchical, surface structure and edge appearance constraints that are redefined and are integrated at the level of individual candidate matches. The algorithm produced a high percentage of correct decisions on a wide-variety of stereo pairs. Its few errors arose when the correlation measures defined by the constraints were either weakened, or ambiguous, as in the case of periodic patterns in the images. Two additional mechanisms are discussed for overcoming the remaining errors. First, an independent estimate of disparity, obtained through a depth-from-focus algorithm, can resolve the ambiguity in periodic regions. Second, a third image, taken from a position above the left image, is incorporated into matching. This is accomplished by defining matches between the new image and the left image, and relating the new and old matches through new constraints. Both of the new approaches are easily easily incorporated into the connectionist network computations of the original algorithm.
Linewidth broadening by 1/f noise in wavelength-tunable laser diodes

The excess linewidth broadening of continuously tunable InGaAsP/InP laser diodes at 1.5 μm wavelength is investigated. Terminal electrical and FM noise measurements indicate that the recombination processes in the forward biased tuning region produce significant 1/f carrier noise. Below 1 MHz the 1/f noise dominates yielding a noise enhancement of about 30 dB at 1 kHz. The discrepancy observed so far between theoretically expected and measured spectral linewidth can be well resolved by taking into account this additional noise source.
Micro-Endoscopic Discectomy versus Open Discectomy: A Struggle for Better Clinical Outcomes

Objective: The objective of the current study was to compare the clinical outcomes of a micro-endoscopic discectomy with an open discectomy. Materials & Methods: This Quasi-experimental study was conducted in the Department of Neurosurgery, Alrazi Healthcare, Lahore, and Ammar Medical Complex, Lahore. The sample consisted of 40 patients with lower back pain with radiation to the lower limbs. A lumbar disc single-segment hernia was diagnosed based on magnetic resonance imaging (MRI) findings. Independent sample t-test was used to explore the difference in outcomes and level of pain between group A and group B. Chi-square test was used to compare the recovery rate of patients in both groups. Results: A significant difference between the two groups in terms of surgery duration (t = 15.977, P = .000), blood loss during surgery (t = -10.256, P = .000), length of incision (t = -58.355, P = .000), and hospital stay after surgery (t = -4.687, P = .000) was found. The overall recovery rate for the micro-endoscopic Discectomy group was 95% whereas, in the open discectomy group, it was 90%. Conclusion: Micro-endoscopic discectomy is superior to open discectomy in terms of lesser surgical trauma, lesser blood loss, lesser hospital stay, earlier return to work, and higher pain resolution.