Miracle-dz/UniFAR-FTUs huggingface dataset:
The Asiago Database of Spectroscopic Databases (ADSD)

Databases of observed stellar spectra are continuously being published and made publicly available, and the average number of stars per database is increasing. This paper reviews the current status. The Asiago Database of Spectroscopic Databases (ADSD) aims to provide a census of publicly available libraries of observed stellar spectra, to document their content and to homogenize their parameters for easier consultation and access. Refereed journals, conference proceedings and personal web pages have been searched for libraries of a given minimum size, properly documented and with data made publicly and directly accessible. A total of 294 databases (54 ultraviolet, 183 optical, 50 infrared and 7 combined) have been found to match the selection criteria and have been included in ADSD. They provide spectra of 16046 different stars in electronic or printed formats. A card for each library describes in a homogeneous way its aims, content, type of data, caveats, data download links, source paper, properties of included stars and more. A dedicated web page allows direct access to ADSD, plans future updates, and provides interrogation tools to search all the libraries matching given characteristics or including any given star.
Transition of Taylor–Görtler vortex flow in spherical Couette flow

The critical Taylor number, phenomena accompanying the transition to turbulence, and the cellular structure of Taylor–Görtler vortex in the flow between two concentric spheres, of which the inner one is rotating and the outer is stationary, are investigated using three kinds of flow-visualization technique. The critical Taylor number generally increases with the ratio β of clearance to inner-sphere radius. For β [les ] 0.08, the critical Taylor number in spherical Couette flow is smaller than in circular Couette flow, but vice versa for β > 0.08. A pair of toroidal Taylor–Görtler vortices occurs first around the equator at the critical Reynolds number Rec (or critical Taylor number Tc). More Taylor–Görtler vortices are added with increasing Reynolds number Re. After reaching the maximum number of vortex cells, as Re is increased, the number of vortex cells decreases along with the various transition phenomena of Taylor–Görtler vortex flow, and the vortex finally disappears for very large Re, where the turbulent basic flow is developed. The instability mode of Taylor–Görtler vortex flow depends on both β and Re. The vortex flows encountered as Re is increased are toroidal, spiral, wavy, oscillating (quasiperiodic), chaotic and turbulent Taylor–Görtler vortex flows. Fourteen different flow regimes can be observed through the transition from the laminar basic flow to the turbulent basic flow. The number of toroidal and/or spiral cells and the location of toroidal and spiral cells are discussed as a means to clarify the spatial organization of the vortex. Toroidal cells are stationary. However, spiral cells move in relation to the rotating inner sphere, but in the reverse direction of its rotation and at about half its speed. The spiral vortices number about six, and the spiral angle is 2–10°.
Analysis of an electromagnetic induction detector for real-time location of buried objects

Spatial response characteristics of an electromagnetic induction sensor as it passes over a metallic object are investigated using a simple analytical technique. In this low-frequency technique, one replaces a metallic object with equivalent electric and magnetic dipoles and then applies the principles of reciprocity to obtain the induced EMF in a sensor coil. Analysis is carried out for a sensor employing rectangular coils, and the object set is confined to a sphere and a prolate spheroid. The simple approach, which is illustrated with both numerical and experimental data, is found to be adequate to understand the effect on the response characteristics of parameters such as object depth, orientation, aspect ratio, and material properties. >
Digital computation of the mutual independance between thin dipoles

This paper presents a method for computing the mutual impedance between any two linear center-fed antennas having sinusoidal current distributions. This method, which is very conducive to digital computer application, is not limited in terms of the lengths or of the relative geometrical configuration of the antennas involved. The method has been used to compute data which have been checked with both published and experimental data for various parallel, echelon, and skew cases. The results of many of these calculations are given.
Properties of optical fibres at cryogenic temperatures

A perhaps surprising property of optical fibres is that they remain flexible at cryogenic temperatures. This implies that they may be used for multiple-object and integral field spectroscopy in the thermal infrared in cryogenic instrumentation. In this paper the results of performance tests of optical fibres (silica and zirconium fluoride) at cryogenic temperatures are presented. By mounting the fibres in glass tubes with the appropriate adhesive, it was found that only negligible focal ratio degradation occurs when the fibre is cooled to 77 K.
Molecular Line Observations of IRAM 04191+1522

We have mapped the CO, HCO+, CS, and N2H+ emission around a low-luminosity Class 0 source IRAM 04191+1522 in the Taurus molecular cloud using the Berkeley-Illinois-Maryland Association array. A bipolar molecular outflow is seen in CO, HCO+, and CS emission originating from around the IRAM source, while a flattened envelope is seen in N2H+ emission surrounding the waist of the molecular outflow around the IRAM source. Outflow, rotation, and probably infall are seen around the Class 0 source, indicating a complicated context for star formation in the earliest stages. The N2H+ envelope is a thick clumpy torus with a tenuous outer part and a ringlike dense inner edge. The dense inner edge has a mean radius of 10'', or 1400 AU. The outer part of the torus exhibits differential rotation, and the infalling material appears to carry angular momentum inward toward the central source. The region surrounded by the inner edge of the torus may have a solid-body rotation. The envelope may result from the collapse of a rotating, magnetized toroid toward the central source. Outflow motion is seen in the outer part of the inner edge of the torus, probably due to an interaction with the molecular outflow. Two armlike structures are seen extending out from the inner edge in the torus. One of them is clearly seen with the velocity increasing roughly linearly with the distance. The HCO+ emission around the source may trace the central core around the source, showing a velocity structure connecting to that of the outer part of the torus. The molecular outflow is best seen in CO. It is bipolar with both a southwest and a northeast lobe. Two internal structures are seen along the main outflow axis within the lobes: (1) a strong CO emission at ~20'' to the northeast of the IRAM source, likely tracing an internal bow shock driven by a collimated, episodic jet and (2) a linear HCO+ structure of ~50'' length at low blueshifted velocity to the southwest of the IRAM source, requiring some interaction with a jet to be produced. In addition, a dense condensation is also seen in HCO+ and CS to the south of the IRAM source, likely representing a recent strong outflow interaction.
γ‐ray‐induced optical attenuation in Ge‐doped‐silica fiber image guides

Optical attenuation in fiber optic image guides comprising germanium‐doped‐silica‐core/ pure‐silica‐clad picture elements was investigated in the range 420‐1100 nm during and after room‐temperature 60Co γ irradiation. The induced absorption spectra of the picture elements were successfully fitted by linear combinations of three known defect bands in irradiated Ge‐doped SiO2: the Ge(1) center, the GeX center, and the nonbridging oxygen hole center (peak positions of 4.4, 2.6, and 2.0 eV, respectively). Dose for dose, the relative strengths of these three bands differed greatly between two nominally identical image guide samples from the same manufacturer. Defect production kinetics were followed at four dose rates ranging from 1.1 to 180 Gy/h. These kinetics and the post‐irradiation anneal behaviors are interpreted in terms of the previously reported tendency of the Ge(1) center to undergo a thermal conversion to GeX. The net effect on absorption at 550 nm is a dose‐rate‐independent linear growth up to ∼10.
FRACTIONAL PROCESSES WITH LONG-RANGE DEPENDENCE

We introduce a class of Gaussian processes with stationary in- crements which exhibit long-range dependence. The class includes fractional Brownian motion with Hurst parameter H > 1/2 as a typical example. We es- tablish infinite and finite past prediction formulas for the processes in which the predictor coecients are given explicitly in terms of the MA( 1) and AR(1) coecients. We apply the formulas to prove an analogue of Baxter's inequal- ity, which concerns the L 1 -estimate of the dierence between the finite and infinite past predictor coecients.
Structural, optical, and electrical properties of Yb-doped ZnO thin films prepared by spray pyrolysis method

Yb-doped ZnO thin films were prepared on glass substrates by spray pyrolysis technique in order to investigate the insertion of Yb ions in the ZnO matrix and the related optical properties of the films. The molar ratio of Yb in the spray solution was varied in the range of 0–5 at. %. X-ray diffraction patterns showed that the undoped and Yb-doped ZnO films exhibit the hexagonal wurtzite crystal structure with a preferential orientation along [002] direction. No secondary phase is observed in Yb-doped ZnO films. All films exhibit a transmittance between 75 and 90% in the visible range with a sharp absorption onset about 375 nm corresponding to the fundamental absorption edge at 3.3 eV. The photoluminescence measurements show a clear luminescence band at 980 nm that is characteristic of Yb3+ transition between the electronic levels F25/2 and F27/2. This is an experimental evidence for an efficient energy transfer from ZnO matrix to Yb3+. Hall effect measurements showed low resistivities and high carrier mob.
The Two-way Channel as a Computer Game

In his 1961 paper on two-way channels (TWC'S) Shannon derived single-letter inner- and outer bounds to the capacity region. The first part of this paper is a survey of earlier results on TWC'S in general and the binary multiplying channel (BMC) in particular. The second part is devoted to a new approach to the problem of determining the capacity region of the BMC. Based on Schalkwijk's 1982 idea to represent symmetric, R1 = R2 = R, coding strategies for deterministic two-way channels as progressive subdivisions of an M x M square, we developed a computer game AXE as a development environment for new coding strategies. Playing AXE is simple and requires no background in information theory.
Evolution of Precambrian life in the Brazilian geological record

Abstract Precambrian rocks comprise nearly one-quarter of the surface of Brazil and range from Paleoarchean (ca. 3.6 Ga) to the latest Ediacaran (0.542 Ga) in age. Except for controversial phosphatized ‘embryo-like’ microfossils like those from the lower Ediacaran Doushantuo Formation, China and complex rangeomorphs, Brazilian research has revealed all major categories of Precambrian life forms described elsewhere – microbialites, biomarkers, silicified microfossils, palynomorphs, vase-shaped microfossils, macroalgae, metazoans, vendobionts and ichnofossils – but the paleobiological significance of this record has been little explored. At least four occurrences of these fossils offer promise for increased understanding of the following aspects of Precambrian biospheric evolution: (i) the relationship of microbialites in 2.1–2.4 Ga old carbonates of the Minas Supergroup in the Quadrilátero Ferrífero, Minas Gerais (the oldest Brazilian fossils) to the development of the early oxygenic atmosphere and penecontemporaneous global tectonic and climatic events; (ii) the evolutionary and biostratigraphic significance of Mesoproterozoic to Ediacaran organic-walled microfossils in central–western Brazil; (iii) diversity and paleoecological significance of vase-shaped heterotrophic protistan microfossils in the Urucum Formation (Jacadigo Group) and possibly the Bocaina Formation (Corumbá Group), of Mato Grosso do Sul; and (iv) insights into the record of skeletogenesis and paleoecology of latest Ediacaran metazoans as represented by the abundant organic carapaces of Corumbella and calcareous shells of the index fossil Cloudina, of the Corumbá Group, Mato Grosso do Sul. Analysis of the Brazilian Precambrian fossil record thus holds great potential for augmenting paleobiological knowledge of this crucial period on Earth and for developing more robust hypotheses regarding possible origins and evolutionary pathways of biospheres on other planets.
The activity of comet C/2007 D1 (LINEAR) at 9.7 AU from the Sun

Aims. We report on the unusual distant activity of the dynamically new comet C/2007 D1 (LINEAR), observed at rh = 9.7 AU postperihelion. This comet is particularly interesting because of its quite large perihelion distance (rq = 8. 8A U). Methods. We analyse V and R band images taken at the TNG telescope to characterise the dust coma of the comet and investigate its photometry, colours, and dust production. Results. The colour of the dust is redder than the Sun (V − R = 0.505 ± 0.093 at the photometric aperture of radius 2.2 �� ). The Afρ value is measured to be 1983 ± 81 cm for an aperture of radius = 2.2 �� . An upper limit to the cometary nucleus radius of aN ≤ 18 km is derived. A dust mass-loss rate of dM d dt = 5.3 × 10 2 kg s −1 is measured, which implies that C/2007 D1 (LINEAR) is a very active
Horizontal fields generated by return strokes

Horizontal fields generated by return strokes play an important role in the interaction of lightning-generated electromagnetic fields with overhead power lines. In many of the recent investigations on the interaction of lightning electromagnetic fields with power lines, the horizontal field was calculated by employing the expression for the tilt of the electric field of a plane wave propagating over the finitely conducting Earth. In this paper we show that the horizontal field generated by return strokes over the finitely conducting ground can be obtained to a high accuracy by using the expression for the surface impedance of the finitely conducting Earth. The method is suitable to calculate horizontal fields generated by return strokes at distances as close as 200 m. At these close ranges the use of the wave tilt expression can cause large errors.
The Effect of Music on Balance Parameters

Abstract Objectives This study aimed to determine the effect of music on balance parameters in healthy individuals. Methods Forty-two participants were included in the study, mean age=23.3 (SD=5.31). Prokin Tecnobody balance device was used for balance measurements. Static and dynamic balance measurements on the dominant foot and bipedal stance were recorded while listening to high-intensity music and without music. Results In the study, there was a statistically significant difference in the dominant foot static mediolateral balance in measurements taken with music (p=0.013). But, there was no difference in other parameters (p>0.05). When examined by gender, it was found that the mediolateral balance scores of females on static and dynamic dominant feet were significantly higher in high-intensity music than males (p<0.05). Conclusion In healthy participants, music improves the mediolateral balance on the dominant foot. Therefore, high-intensity music can be a safe and motivating method to be used in addition to clinical applications.
Stochastic estimation of organized turbulent structure: homogeneous shear flow

The large-scale organized structures of turbulent flow can be characterized quantitatively by a conditional eddy, given the local kinematic state of the flow as specified by the conditional average of u(x’, t) given the velocity and the deformation tensor at a point x: 〈u(x’, t)|u(x, t), d(x, t)〉. By means of linear mean-square stochastic estimation, 〈u’|u, d〉 is approximated in terms of the two-point spatial correlation tensor, and the conditional eddy is evaluated for arbitrary values of u(x, t) and d(x, t), permitting study of the turbulent field for a wide range of local kinematic states. The linear estimate is applied to homogeneous turbulent shear flow data generated by direct numerical simulation. The joint velocity-deformation probability density function is used to obtain conditions corresponding to those events that contribute most to the Reynolds shear stress. The primary contributions to the second-quadrant and fourth-quadrant Reynolds-stress events in homogeneous shear flow come from flow induced through the ‘legs’ and close to the ‘heads’ of upright and inverted ‘hairpins’, respectively. The equation governing the joint probability density function of fu,d (u, d) is derived. It is shown that this equation contains 〈u’/u, d〉 and that the equations for second-order closure can be derived from it. Closure requires approximation of 〈u’/u, d〉.
THE NORTHERN LIMIT OF THE ZODIACAL LIGHT

The boundaries of the zodiacal light are hard to determine because of the faintness of the phenomenon, although the light along the axis is quite strong and can be seen even in cities in spite of the electric illumination. From the usual observations of the boundaries of this light we should expect the light to extend about 20 to the north and south of the Sun. That the zodiacal light is of much greater extent is evident from the observations described below. In the summer of 1907 Director Campbell, of the Lick' Observatory, called the writer's attention to a faint light, which for years has been seen in the summer by various observers at Mount Hamilton, extending along our northern horizon near midnight, and asked that an attempt be made to determine its character. Observations were accordingly begun and continued during the summer of 1908. The general appearance of the phenomenon when observed near midnight, with a clear sky and no Moon, is that of a flat arch of light with its maximum intensity near the north point of the horizon. At that time of night in the early part of July, 1908, the greatest altitude above the northern horizon was 18. It extended westward about 40 and eastward to the Milky Way, and was symmetrical with respect to the meridian. At the extremities it was only a degree or two above the horizon, depending on the clearness of the air at such a low altitude. When, however, the observations were
The photoluminescence emission in the 0.7-0.9 eV range from oxygen precipitates, thermal donors and dislocations in silicon

There is a wide set of literature reports that suggest that over-coordinated oxygen or self-interstitials are, directly or indirectly, the chemical bridge between thermal donors, oxygen precipitates and dislocations, capable of supporting a common origin of their emission features in the 0.7-0.9 eV range. Finding the experimental proof of these suggestions was the aim of this present work, which required both appropriate preparation of samples and their careful optical, electrical and microscopical characterization. We were able to show not only that the photoluminescence emissions from oxide precipitates could be correlated to their density and to the presence of closed dislocation rings around them, but also that the precursors of dislocations are optically active as well. For samples thermally annealed in the range of thermal donors, we were able to show that their optical activity seems to be correlated to a transition from a shallow donor level of thermal donors to a deep level of a CiO2 complex.
On the circle polynomials of Zernike and related orthogonal sets

ABSTRACT The paper is concerned with the construction of polynomials in two variables, which form a complete orthogonal set for the interior of the unit circle and which are ‘invariant in form’ with respect to rotations of axes about the origin of coordinates. It is found that though there exist an infinity of such sets there is only one set which in addition has certain simple properties strictly analogous to that of Legendre polynomials. This set is found to be identical with the set of the circle polynomials of Zernike which play an important part in the theory of phase contrast and in the Nijboer-Zernike diffraction theory of optical aberrations. The results make it possible to derive explicit expressions for the Zernike polynomials in a simple, systematic manner. The method employed may also be used to derive other orthogonal sets. One new set is investigated, and the generating functions for this set and for the Zernike polynomials are also given.
Aluminium back-surface field doping profiles with surface recombination velocities below 200 cm/s

In this paper, the authors show that a Si solar cell Al back-surface field (BSF) doping profile is formed by a fast alloying and regrowth process in accordance with the Al-Si phase diagram, and not by solid-state Al diffusion. Al was screenprinted on 3 /spl Omega/cm monocrystalline CZ wafers. Subsequently a temperature treatment of 30 seconds was given at 850/spl deg/C. The Al doping profiles were measured by SIMS, CV and Stripping Hall. The doping profiles show a peak concentration at a depth of around 10 /spl mu/m and are clearly different from diffusion profiles. The recorded profiles are in good agreement with each other. The peak and surface concentrations are close to the solid solubilities of Al in Si at 850/spl deg/C and at the eutectic temperature, respectively. The thickness of the profile correlates with the composition of the alloy liquid at 850/spl deg/C and the amount of deposited Al. Surface recombination velocities between 130 cm/s and 170 cm/s were measured with photoconductivity decay (PCD), probed by microwaves. These results agree with numerical calculations using the measured profiles. The minority carrier lifetime and mobility in the Al doped BSF appear to be lower than in borium doped Si. <<ETX>>
Does Globalization Impact Entrepreneurship?

Purpose: This paper examines the effect of the globalization phenomenon and its impact on the dynamic development of entrepreneurship based on changing economic, cultural, and business environments both within and between nations. Design/methodology/approach: The authors use theoretical perspectives and analyze literature reviews to identify the effect of the relationship that exists between globalization and entrepreneurship, which plays a variety of important roles in the business world. Findings: The findings of the study show that while there is a significant statistical difference between U.S. and international entrepreneurs regarding the importance of cross-cultural considerations, there are no statistical differences regarding the importance of global entrepreneurial innovation, business environment, and the effect of globalization on the economy. Research limitations/implications: The paper presents a critical analysis of the impact of globalization on entrepreneurs in the U.S. and internationally. Practical implications: The authors investigate the characteristics necessary for entrepreneurs to be successful, such as skills, knowledge, experience, and the abilities needed to apply technology and innovation, and they navigate complex cultural differences that may exist between business members and stakeholders from diverse cultural backgrounds. Paper type: Research paper