Miracle-dz/UniFAR-FTUs huggingface dataset:
Raman spectroscopy of graphene and carbon nanotubes

This paper reviews progress that has been made in the use of Raman spectroscopy to study graphene and carbon nanotubes. These are two nanostructured forms of sp2 carbon materials that are of major current interest. These nanostructured materials have attracted particular attention because of their simplicity, small physical size and the exciting new science they have introduced. This review focuses on each of these materials systems individually and comparatively as prototype examples of nanostructured materials. In particular, this paper discusses the power of Raman spectroscopy as a probe and a characterization tool for sp2 carbon materials, with particular emphasis given to the field of photophysics. Some coverage is also given to the close relatives of these sp2 carbon materials, namely graphite, a three-dimensional (3D) material based on the AB stacking of individual graphene layers, and carbon nanoribbons, which are one-dimensional (1D) planar structures, where the width of the ribbon is on the nanometer length scale. Carbon nanoribbons differ from carbon nanotubes is that nanoribbons have edges, whereas nanotubes have terminations only at their two ends.
Resistance training variables on muscle hypertrophy: a systematic review

Resistance training (RT) is a widely practised type of training, and the number of adherents of this type of physical exercise is increasing each year. Among the most sought objectives of those who initiate RT is muscle hypertrophy, although success in this process depends on a well-designed protocol and good manipulation of training variables. The present study aims to analyse, through a systematic review, the impact of the RT variables (such as intensity, volume, recovery interval, execution speed, and concentric muscle failure) relevant to muscle hypertrophy and if there is an ideal range for each training variable. The research was carried out in the PubMed, Web of Science, Scopus and Scielo databases from 2000 to 2020, using the terms “resistance training” and “hypertrophy” and “intensity” or “volume” or “recovery interval” or “execution speed” or “muscular failure”. Twenty-three articles were included in the review. The PEDro scale was used to analyse the quality of the selected articles. It was concluded that the variables intensity and volume must be carefully analysed in a training program. Despite not having a direct impact on hypertrophy, the other variables affect the intensity and volume and must be manipulated according to what is intended with the others.
Spectral Energy Distribution and Abundances of NGC 288 Stars

NGC 288, an intermediate Population II globular cluster located near the south Galactic pole, has a dominant blue horizontal branch, intermediate metallicity, and age about 15 Gyr. It has been investigated in a number of studies using spectrophotometric techniques. We present here new spectral energy distributions (SEDs) of bright stars in NGC 288 constructed using 12 of the BATC (Beijing Arizona Taipei Connecticut) 15 intermediate-band filter systems. Using Kurucz models, we have estimated reliable effective temperatures for stars and [Fe/H] = -1.24 ± 0.04. Using theoretical isochrones that Worthey has calculated for our filter set, we obtain a distance modulus of m-M = 14.57 ± 0.07 for this cluster. The purpose of this study is to establish a stellar SED data bank by using cluster stars of different age, temperature, abundance and surface gravity. The SEDs for the stars in NGC 288 form part of this data bank, which will be used for future studies of objects in Selected Area fields.
Implementation of SIMADE: analysis of the performance of school principals Implementação do SIMADE: análise da atuação dos diretores escolares Implementación del SIMADE: análisis del desempeño de los directores escolares

Creative Commons license CC BY 4.0. Abstract: This article analyzes the implementation of the Sistema Mineiro de Administração Escolar (SIMADE) from the discretion of middle-level bureaucrats: the principals of the state public schools. Methodologically, it is a quantitative research in which it is observed: a gap between the formulation and the implementation of the policy; the production of new rules regarding the access and use of the system; implementation aimed at the administrative or pedagogical use of SIMADE. Therefore, there is a continuous work of discretion through which school principals build different policies in the context of the public state network of Minas Gerais.
Comparison of exercise and sports characteristics between binge-eating and healthy people

The present study compared exercise and sports characteristics between subjects with Binge Eating Disorder (BD) classification and a health group without binge eating. A randomized sample of 111 participants (23.1 ± 7.6 yrs.; 1.6 ± 0.6 m; 77.0 ± 16.9 kg) were classified and separated according BD classification (non-binging= 47; moderate binging n = 30; severe binging n = 40). For this, the BD Scale, Self-perceived Performance Scale, and a Demographic Questionnaire obtained classifications about BD and characteristics of exercise and sports practices. Analysis indicated that the Body Mass Index (BMI) was different between groups ( p ≤ 0.001). Non-binging, with 22.5 ± 5.1 index, presented lower values than severe binging, with 27.4 ± 4.9 index and moderate, binging, with 28.1 ± 8.2 index, while severe binging, with 6 (2; 6) hours/training, had a longer time than moderate, with 4 (2; 6) hours and non-binging groups, with 3 (2; 6) hours/training. With a 3 (2.5; 3) score, the severe binging group presented lower motor control performance than the non-binging with a 3 (3; 4) score. Thus, coaches and psychologists can develop strategies for specific eating disorders, considering present important factors in sports psychology to reduce BD and compensatory strategies.
Amorphous versus Crystalline GeTe Films. I. Growth and Structural Behavior

As a part of our structural, optical, and electrical studies of amorphous versus crystalline GeTe films, this paper (Part I) reports on the growth and structural properties of the thin‐film polymorphs (amorphous, rhombohedral, and NaCl) of GeTe. When deposited above ∼130°C, the GeTe films are polycrystalline. Epitaxial or partially oriented growth of the rhombohedral phase is obtained on NaCl and mica at deposition temperatures ∼250°C. An electric field ∼4000 V/cm applied laterally on the substrate during deposition lowers the epitaxial temperature. At temperatures above 250°C, the high‐temperature NaCl structure grows epitaxially. Below a deposition temperature of ∼130°C, the films are amorphous. The amorphous phase transforms very rapidly via random nucleation centers to the crystalline phase at a well‐defined temperature of 145±3°C accompanied by the release of heat ∼1±0.2 kcal/mole (∼½kTm, where k is Boltzmann's constant and Tm is the melting point of GeTe). The transformation temperature increases li.
Modelling the Streamline Curvature Effects in Turbomachinery Flows

Turbomachinery flows show significant streamline curvature with corresponding effects on turbulence development. Generally, linear eddy viscosity turbulence models, which are widely used in industrial aerodynamic design, do not predict these effects accurately, leading to less reliable RANS-simulations. In this work, therefore, a modification is made to the two-equation turbulence model of Wilcox [1]. Although this extension is a simple and pragmatic approach, the effects of streamline curvature are accurately reproduced for many presented applications, ranging from simple generic test cases to multistage compressor flows. Improved predictions of performance maps are achieved, which is mainly due to improved modelling in regions with higher streamline curvature, e.g. tip vortex and end-wall boundary layers. The curvature correction enables a greater mass flow range to be simulated and increases the numerical stability. Furthermore, the new approach requires only local variables, which makes it applicable to complex flows and easy to implement in existing codes.Copyright © 2006 by ASME
A variable Krasnosel'skii–Mann algorithm and the multiple-set split feasibility problem

A variable Krasnosel'skii–Mann algorithm generates a sequence {xn} via the formula xn+1 = (1 − αn)xn + αnTnxn, where {αn} is a sequence in [0, 1] and {Tn} is a sequence of nonexpansive mappings. We will show, in a fairly general Banach space, that the sequence {xn} generated converges weakly. This result is used to solve the split feasibility problem which is to find a point x with the property that x ∊ C and Ax ∊ Q, where C and Q are closed convex subsets of Hilbert spaces H1 and H2, respectively, and A is a bounded linear operator from H1 to H2. The multiple-set split feasibility problem recently introduced by Censor et al is stated as finding a point x ∊ ∩Ni=1Ci such that Ax ∊ ∩Mj=1Qj, where N and M are positive integers, {C1, …, CN} and {Q1, …, QM} are closed convex subsets of H1 and H2, respectively, and A is again a linear bounded operator from H1 to H2. One of the purposes of this paper is to introduce more iterative algorithms that solve this problem in the framework of infinite-dimensional Hilbert spaces.
Forecasting Techniques Utilized by the Forecast Branch of the National Meteorological Center During a Major Convective Rainfall Event

Abstract Meteorologists within the Forecast Branch (FB) of the National Meteorological Center (NMC) produce operational quantitative precipitation forecasts (QPFs). These manual forecasts are prepared utilizing various forecasting techniques, which are based on the subjective analysis and interpretation of the observed data and numerical model output. The manual QPFs from NMC generally have proven very successful in improving model QPF. This paper discusses several of the forecasting techniques employed by the FB, emphasizing the importance of subjective interpretation of the model guidance. The use of these methods in preparing a manual QPF for a heavy convective rainfall and flash-flood event that occurred over the southern Plains on 27–28 May 1987 is then examined. Results indicate that the manual QPF was quite successful in improving the models’ QPF and generally related well to the observed rainfall of up to 8 inches in this case. Thus, the importance of utilizing subjective techniques in preparing p.
Deriving Stopping Rules for Multidimensional Computerized Adaptive Testing

Multidimensional computerized adaptive testing (MCAT) is able to provide a vector of ability estimates for each examinee, which could be used to provide a more informative profile of an examinee’s performance. The current literature on MCAT focuses on the fixed-length tests, which can generate less accurate results for those examinees whose abilities are quite different from the average difficulty level of the item bank when there are only a limited number of items in the item bank. Therefore, instead of stopping the test with a predetermined fixed test length, the authors use a more informative stopping criterion that is directly related to measurement accuracy. Specifically, this research derives four stopping rules that either quantify the measurement precision of the ability vector (i.e., minimum determinant rule [D-rule], minimum eigenvalue rule [E-rule], and maximum trace rule [T-rule]) or quantify the amount of available information carried by each item (i.e., maximum Kullback–Leibler divergence rule [K-rule]). The simulation results showed that all four stopping rules successfully terminated the test when the mean squared error of ability estimation is within a desired range, regardless of examinees’ true abilities. It was found that when using the D-, E-, or T-rule, examinees with extreme abilities tended to have tests that were twice as long as the tests received by examinees with moderate abilities. However, the test length difference with K-rule is not very dramatic, indicating that K-rule may not be very sensitive to measurement precision. In all cases, the cutoff value for each stopping rule needs to be adjusted on a case-by-case basis to find an optimal solution.
On the Opimality of $( {s,S} )$ Inventory Policies: New Conditions and a New Proof

Scarf [6] has shown that the $( {s,S} )$ policy is optimal for a class of discrete review dynamic nonstationary inventory models. In this paper a new proof of this result is found under new conditions which do not imply and are not implied by Scarf’s hypotheses. We replace Scarf’s hypothesis that the one period expected costs are convex by the weaker assumption that the negatives of these expected costs are unimodal. On the other hand we impose the additional assumption not made by Scarf that the absolute minima of the one, period expected costs are (nearly) rising over time. For the infinite period stationary model, this last hypothesis is automatically satisfied. Thus in this case our hypotheses are weaker than Scarf’s. The bounds on the optimal parameter values given by Veinott and Wagner [12] are established for the present case. The bounds in a period are easily computed, and depend only upon the expected costs for that period. Moreover, simple conditions are given which ensure that the optimal param.
Assimilating high-resolution winds from a Doppler lidar using an ensemble Kalman filter with lateral boundary adjustment

Monitoring severe weather, including wind shear and clear air turbulence, is important for aviation safety. To provide accurate information for nowcasts and very short-range forecasts up to an hour, a rapid-update prediction system has been developed, with a particular focus on lateral boundary adjustment (LBA) using the local ensemble transform Kalman filter (LETKF). Due to the small forecast domain, limited-area forecasts are dominated by the lateral boundary conditions from coarse-resolution global forecasts. To effectively extend the forecast lead time for the small domain, a new LBA scheme using the LETKF has been developed and assessed with three sea-breeze front cases. Observing system simulation experiments for high-resolution winds from a simulated Doppler lidar were performed with the Japan Meteorological Agency Nonhydrostatic Mesoscale Model at a horizontal resolution of 400 m and 15-minute update cycle. The results indicate that the LBA improved the forecast significantly. In particular, the 1-hour wind-speed forecast with the LBA is as accurate as the 15-minute forecast without the LBA. The assimilation of Doppler lidar high-resolution wind data with the LBA is a promising approach for very short-range forecasts up to an hour with a small domain, such as for aviation weather.
Faint object 3D spectroscopy with PMAS

PMAS is a fiber-coupled lens array type of integral field spectrograph, which was commissioned at the Calar Alto 3.5m Telescope in May 2001. The optical layout of the instrument was chosen such as to provide a large wavelength coverage, and good transmission from 0.35 to 1 μm. One of the major objectives of the PMAS development has been to perform 3D spectrophotometry, taking advantage of the contiguous array of spatial elements over the 2-dimensional field-of-view of the integral field unit. With science results obtained during the first two years of operation, we illustrate that 3D spectroscopy is an ideal tool for faint object spectrophotometry.
Radiocarbon Reservoir Ages in the Mediterranean Sea and Black Sea

We measured apparent marine radiocarbon ages for the Mediterranean Sea, Black Sea, and Red Sea by accelerator mass spectrometry radiocarbon analyses of 26 modern, pre-bomb mollusk shells collected living between AD 1837 and 1950. The marine reservoir (R(t)) ages were estimated at some 390 ± 85 yr BP, 415 ± 90 yr BP and 440 ± 40 yr BP, respectively. R(t) ages in the Mediterranean Sea and Black Sea are comparable to those for the North Atlantic Ocean (<65°N), in accordance with the modern oceanic circulation pattern. The ΔR values of about 35 ± 70 yr and 75 ± 60 yr in the Mediterranean area show that the global box-diffusion carbon model, used to calculate R(t) ages, reproduces the measured marine 14C R(t) ages in these oceanic areas. Nevertheless, high values of standard deviations, larger than measurement uncertainties are obtained and express decadal R(t) changes. Such large standard deviations are indeed related to a decrease of the apparent marine ages of some 220 yr from 1900 AD to 1930 AD in both the Mediterranean Sea and the western North Atlantic Ocean.
Efficient estimation in image factor analysis.

The image factor analytic model (IFA), as related to Guttman's image theory, is considered as an alternative to the traditional factor analytic model (TFA). One advantage with IFA, as compared with TFA, is that more factors can be extracted without yielding a perfect fit to the observed data. Several theorems concerning the structural properties of IFA are proved and an iterative procedure for finding the maximum likelihood estimates of the parameters of the IFA-model is given. Substantial experience with this method verifies that Heywood cases never occur. Results of an artificial experiment suggest that IFA may be more factorially invariant than TFA under selection of tests from a large battery.
Control of uncertain linear systems with a state delay based on an uncertainty and disturbance estimator

Abstract In this paper, a robust control strategy based on the uncertainty and disturbance estimator (UDE) is extended and applied to uncertain linear continuous-time systems with state delays and disturbances. It does not require the knowledge of the bounds of uncertainties and disturbances. Both known and unknown delay cases are considered. In the case of an unknown time delay, the term with the delay is treated as an additional disturbance to the system. The proposed algorithm shows excellent tracking and disturbance rejection capabilities. The robust stability of LTI-SISO systems is analysed and simulations are given to show the effectiveness of the UDE-based control.
Spectroscopic studies of O-type binaries. IV - HD 165052 and HD 167771

HD 165052, O6.5 V, and HD 167771, 07.5 III ((f)), are double-lined binaries with periods of six and four days, respectively, and velocity semiamplitudes near 100 km s/sup -1/. In our spectroscopic orbital analysis, we investigated the effect of correcting the measured radial velocities for pair blending. The derived velocity amplitudes are increased by roughly 7%, and hence the minimum masses increase by 20%--255. The raw data lead to minimum masses, m sin/sup 3/ i, between 2 and 3 mD/sub sun/. Since normal O stars are thought to have masses greater than 20 m/sub sun/, the orbits must be highly inclined to the line of sight. From the luminosities and effective temperatures we derived stellar radii. For HD 167771, the requirement that neither component over fill it Roche lobe implies that each has a mass in the neighborhood of 30m/sub sun/ or larger.
On distinguishing multiple changes in mean and long-range dependence using local Whittle estimation

Abstract: It is well known that changes in mean superimposed by a shortrange dependent series can be confused easily with long-range dependence. A procedure to distinguish the two phenomena is introduced. The proposed procedure is based on the local Whittle estimation of the long-range dependence parameter applied to the series after removing changes in mean, and comparing the results to those obtained through the available CUSUM-like approaches. According to the proposed procedure, for example, volatility series in finance seem more consistent with the changes-in-mean models whereas hydrology and telecommunication series are more in line with longrange dependence. As part of this work, a new method based on the local Whittle estimation to find the number of breaks is also introduced and its consistency is proved for the changes-in-mean models.
Microwave magnetoabsorption in glass-coated amorphous microwires with radii close to skin depth

We present the frequency dependence of microwave magnetoabsorption in glass-coated amorphous microwires of (Co100−xFex)72.5Si12. 5B15. The data were taken at room temperature in the frequency range of 1–60 GHz for fields up to 15 kOe by either a cavity perturbation technique or a coaxial transmission line. The resulting spectra strongly depend upon the local microwave magnetic and electric fields. We have found that we can simulate the spectra using an analytic solution to the problem of electromagnetic scattering from a cylinder. We demonstrate that these unusual spectra can be interpreted in terms of ferromagnetic resonance and antiferromagnetic resonance. However, because the electromagnetic skin depth is comparable to the radius, the resonance and antiresonance fields do not follow the conventional equations.
Fast and Slow Waves in the FitzHugh–Nagumo Equation

Abstract It is known that the FitzHugh–Nagumo equation possesses fast and slow travelling waves. Fast waves are perturbations of singular orbits consisting of two pieces of slow manifolds and connections between them, whereas slow waves are perturbations of homoclinic orbits of the unperturbed system. We unfold a degenerate point where the two types of singular orbits coalesce forming a heteroclinic orbit of the unperturbed system. Let c denote the wave speed and e the singular perturbation parameter. We show that there exists a C 2 smooth curve of homoclinic orbits of the form ( c , e ( c )) connecting the fast wave branch to the slow wave branch. Additionally we show that this curve has a unique non-degenerate maximum. Our analysis is based on a Shilnikov coordinates result, extending the Exchange Lemma of Jones and Kopell. We also prove the existence of inclination-flip points for the travelling wave equation thus providing the evidence of the existence of n -homoclinic orbits ( n -pulses for the FitzHugh–Nagumo equation) for arbitrary n .
On a Hele-Shaw flow with a time-dependent gap in the presence of surface tension

The introduction of surface tension into a Hele-Shaw problem makes it more realistic from the physical viewpoint, but more difficult from the mathematical viewpoint. In this paper we discuss a Hele-Shaw flow with a time-dependent gap taking into account the surface tension of the free boundary. We use the Schwarz function method to find asymptotic solutions for the interior problem in the case when the initial shape of the droplet is a weakly distorted circle.
On the generalized mth decomposable numerical radius on symmetry classes of tensors

In this note, we classify the generalized mth decomposably spectral operators, the generalized mth decomposably radial operators and the operators whose induced operators are spectral or radial on symmetry classes of tensors. A characterization is also obtained of scalar multiples of unitary operators in terms of the unitary invariance of the generalized mth decomposable numerical radius. The results obtained constitute generalizations of some works of Andresen, Filippenko, Li and Marcus.
Amorphization of a substitutional binary alloy: a computer 'experiment'

A novel route towards amorphization of an initially crystalline structure is explored by molecular dynamics simulations of a two-dimensional model of 'soft-disk' atoms. Amorphization is driven by a slow increase in the diameters of half the atoms, chosen at random on an initially monodisperse triangular lattice, and a simultaneous reduction in size of the remaining atoms, keeping constant a suitably chosen mean diameter as well as the temperature. The crystal is found to undergo a discontinuous transition towards an amorphous solid at a critical size ratio of the two species. The transition is signalled by jumps of a number of order parameters characterizing the loss of long-range positional and bond-orientational order, and by hysteresis reminiscent of a first-order phase transition. At higher temperatures, a similar adiabatic change in the size ratio leads to melting.