Miracle-dz/UniFAR-FTUs huggingface dataset:
Probabilistic principal component analysis to identify profiles of physical activity behaviours in the presence of non‐ignorable missing data

The paper is motivated by an accelerometer‐based study of physical activity (PA) behaviours in a large cohort of UK school‐aged children. Advances in research on PA are accompanied by a growing number of results that are contributing to form a complex picture of PA behaviours in children. One source of such complexity is intimately related to the multiplicity of dimensions associated with PA. Currently a comprehensive individual accelerometer summary can include a large number of outcomes and this clearly poses challenges for the analysis. We explore the application of principal component analysis to accelerometer measurements that are aggregated daily over several days of the week and are affected by missingness. The probabilistic approach to principal component analysis with latent scores is extended to include non‐ignorable missing data. The extended likelihood is maximized through a Monte Carlo EM algorithm via adaptive rejection Metropolis sampling. Our findings suggest that physical activity and inactivity are two dimensions over which children aggregate into distinct behavioural profiles, characterized by gender and season but not by anthropometric factors.
The Evolution of Photochemical Smog in the Metropolitan Area of Santiago de Chile

In November and December 1996 the PHOTOCHEMICAL CAMPAIGN took place in the Metropolitan Area of Santiago de Chile and covered a range of simultaneous measurements of meteorological parameters and air chemical compounds, including ozone, carbon monoxide, nitrogen oxides, peroxyacetyl nitrate (PAN), and online nonmethane hydrocarbons (NMHC) in the range of C4‐C12. Measurements were obtained at a downtown site and a receptor site. In addition to high ozone concentrations, Santiago faces high PAN values that can reach to more than 20 ppbv. It is estimated that more than 50% of the daytime maximum of ozone and almost all PAN are formed within the urban plume. Ozone : PAN ratios for diurnal maxima were about 7.7. The behavior of PAN is linked strongly to anthropogenic species, especially aromatic compounds, whereas biogenic NMHC also may contribute to afternoon ozone concentrations. The ethylbenzene : m-xylene ratio can be used as a good indicator for the effect of anthropogenically related hydrocarbon chemical reactions that lead to the formation of secondary pollutants. Using this ratio, mixing ratios for hydroxyl radical (OH) were calculated. Mean diurnal maximum OH mixing ratios were about 2.9 3 106 molecules per centimeter cubed.
Dynamic Control of Brownian Networks: State Space Collapse and Equivalent Workload Formulations

Brownian networks are a class of linear stochastic control systems that arise as heavy traffic approximations in queueing theory. Such Brownian system models have been used to approximate problems of dynamic routing, dynamic sequencing and dynamic input control for queueing networks. A number of specific examples have been analyzed in recent years, and in each case the Brownian network has been successfully reduced to an "equivalent workload formulation" of lower dimension. In this article we explain that reduction in general terms, using an orthogonal decomposition that distinguishes between reversible and irreversible controls.
Preparation of Pyrochlore-Free PMN by an Alternative Chemical Method

This work reports the synthesis of the MgNb2O6 and the ferroelectric lead magnesium niobate Pb(Mg1/3Nb2/ 3)O3 (PMN) using fine precursor powders obtained from a chemical Oxide Precursor Method (OPM). To obtain pyrochlore-free PMN ceramics, the synthesis of the precursor MgNb2O6 powders was studied for 2–25 mol% excess of MgO and 10 mol% excess of PbO. Structural and microstructural properties of the sintered ceramics obtained by the cited method and by the classical columbite method were studied and compared. Results lead to good quality pyrochlore-free PMN ceramic prepared by OPM, presenting greater grain size if compared with ceramic prepared by columbite method.
A distance-based decision making method to improve multiple criteria supplier selection

This article extends the Ng-model for multiple criteria supplier selection problem based upon a distance-based decision-making method. The proposed method determines the common weights associated with all rankings of the criteria importance, and then provides a comprehensively scoring scheme by aggregating all rankings. A numerical illustration is presented to compare our computational results with that of the Ng-model.
Low subthreshold slope in junctionless multigate transistors

The improvement of subthreshold slope due to impact ionization is compared between “standard” inversion-mode multigate silicon nanowire transistors and junctionless transistors. The length of the region over which impact ionization takes place, as well as the amplitude of the impact ionization rate are found to be larger in the junctionless devices, which reduces the drain voltage necessary to obtain a sharp subthreshold slope.
Nonlinear coupling and squeezing in solid-state quantum circuits

We propose an attractive realization of nonlinear coupling of superconducting charge qubit coupled to a transmission-line resonator. Our scheme provides a new approach to produce the strong squeezing effect via a flexible design of the superconducting qubit and mature experimental setup of circuit QED. By properly tuning the external magnetic flux, considerable squeezing can be generated. Strong coupling strength, immunity to noises and suppression of spontaneous emission make our scheme more robust and may be realized with conservative experimental parameters.
Sulla interpretazione dei parametri dei modelli analitici per la distribuzione del reddito personale

For continuos and non-negative random variables, Zenga specifies a partial ordering using ratio between population quantiles of income distribution as a fruitful device to obtain a partial ordering of Lorenz's and Zenga's concentration curves respectively. The purpose of this paper is to use Zenga's contribution to investigate the concentration curves behaviour when one inequality parameter changes while the others remain constant. An important feature of this ratio between population quantiles is that it gives a straightforward information about the Lorenz' and Zenga's concentration curves behaviour without requiring the numerical knowledge or estimation of their mathematical forms. The quantiles ratio is used to analyse the concentration behaviour resulting from changes of each inequality parameter at a time for the following income distribution models lognormal, Singh and Maddala, Dagum Type I, and the generalized-Pareto specified by Stoppa.
MÉTODOS DIRECTOS PARA LA SOLUCIÓN DE SISTEMAS DE ECUACIONES LINEALES SIMÉTRICOS, INDEFINIDOS, DISPERSOS Y DE GRAN DIMENSIÓN

This work centers in the optimization of the methods for solving linear equation systems with sparse, symmetric, indefinite, large associated matrices. The methods are defi ned in parallel computation environments, making use of optimization libraries and looking for a correct use of sparse matrices to reach maximum optimization of the methods defined for solving linear equations systems with associated matrices that posses the aracteristics mentioned above.
Smoothed functional principal components analysis by choice of norm

The principal components analysis of functional data is often enhanced by the use of smoothing. It is shown that an attractive method of incorporating smoothing is to replace the usual L 2 -orthonormality constraint on the principal components by orthonormality with respect to an inner product that takes account of the roughness of the functions. The method is easily implemented in practice by making use of appropriate function transforms (Fourier transforms for periodic data) and standard principal components analysis programs. Several alternative possible interpretations of the smoothed principal components as obtained by the method are presented. Some theoretical properties of the method are discussed: the estimates are shown to be consistent under appropriate conditions, and asymptotic expansion techniques are used to investigate their bias and variance properties. These indicate that the form of smoothing proposed is advantageous under mild conditions, indeed milder than those for existing methods of smoothed functional principal components analysis. The choice of smoothing parameter by cross-validation is discussed. The methodology of the paper is illustrated by an application to a biomechanical data set obtained in the study of the behaviour of the human thumb-forefinger system.
Reduction of Linear Dynamic Systems using Routh Hurwitz Array and Factor Division Method

A new algorithm based on factor division and Routh Hurwitz array is proposed for reducing the order of the system. Reciprocal transformation & Routh Hurwitz array are used to obtain biased denominators while numerator is obtained with the help of factor division method. This method gives stable reduced models of stable system and also preserves initial time moments of orginal system. The proposed method is compared with the well-known hankel norm approximation method.
Statistical Characteristics of Multipeak Raindrop Size Distributions at the Surface and Aloft in Different Rain Regimes

Abstract Two years (∼672 h) of lower-atmospheric wind profiler (LAWP) and 4 yr (∼733 h) of Joss–Waldvogel disdrometer measurements are utilized to study the multipeak (MP) occurrence statistics at the surface and aloft. For the first time, an attempt has been made to address several key questions regarding MPs: their occurrence statistics and their dependency on height, season, and type of precipitation. MPs are not exceptional; rather, they are observed at all altitudes, albeit with different occurrence percentages. The occurrence of MPs seems to be height dependent, and this dependency varies with the type of rain system. The occurrence percentage of bimodal echo (two peaks) is high above (below) the melting level (ML) in convection (in other types of rain). The percentage occurrence of bimodal echo in warm rain is similar to that in cold rain, but only below the ML. The spectrum with more than two peaks appears to be predominantly in convection, particularly above 4 km. The MP statistics on the surface.
Full automatic preprocessing of digital map for 2.5D ray tracing propagation model in urban microcellular environment

Due to the importance of digital map to ray-tracing (RT) algorithm, intelligent preprocessing techniques for the geometric information of buildings are improved, taking into account the characteristic of quasi three-dimensional (2.5D) RT method. By using these techniques, the geometrical factors, which have little or no effect on the prediction results, are neglected from the digital map, and the reduction of the number of blocking test is achieved in the process of executing the RT routine. With the proposed preprocessing of the digital map in urban microcellular environments, the improvement in the computational efficiency is clearly demonstrated without sensibly affecting the accuracy of the propagation prediction.
Electrical Contact Resistance of Large-Area Graphene on Pre-Patterned Cu and Au Electrodes

Contact resistance between electrically connected parts of electronic elements can negatively affect their resulting properties and parameters. The contact resistance is influenced by the physicochemical properties of the connected elements and, in most cases, the lowest possible value is required. The issue of contact resistance is also addressed in connection with the increasingly frequently used carbon allotropes. This work aimed to determine the factors that influence contact resistance between graphene prepared by chemical vapour deposition and pre-patterned Cu and Au electrodes onto which graphene is subsequently transferred. It was found that electrode surface treatment methods affect the resistance between Cu and graphene, where contact resistance varied greatly, with an average of 1.25 ± 1.54 kΩ, whereas for the Au electrodes, the deposition techniques did not influence the resulting contact resistance, which decreased by almost two orders of magnitude compared with the Cu electrodes, to 0.03 ± 0.01 kΩ.
Robust H ∞ Control for a Class of Uncertain Switched Fuzzy Time-Delay Systems Based on TS Models

The problem of robustH ∞ control for a class of uncertain switched fuzzy time-delay systems is discussed for system described by T-S fuzzy model with Lyapunov stable theory and linear matrix inequality approach. A sufficient condition in terms of the LMI is derived such that the stability of the closed-loop systems is guaranteed. The continuous state feedback controller is built to ensure the asymptotically stable closed-loop system for all allowable uncertainties, with the switching law designed to implement the global asymptotic stability of uncertain switched fuzzy time-delay systems. In this model, each and every subsystem of the switched systems is an uncertain fuzzy one to which the parallel distributed compensation (PDC) controller of each sub fuzzy system system is proposed with its main condition given in amore solvable form of convex combinations. Such a switched control system is highly robust to varying parameters. A simulation shows the feasibility and effectiveness of the design method.
An investigation of mesoscale flows induced by vegetation inhomogeneities using an evapotranspiration model calibrated against HAPEX-MOBILHY data.

Abstract Many recent studies have suggested that heterogeneities in soil properties or vegetation characteristics many trigger mesoscale circulations in planetary boundary layer (PBL). Unfortunately, these flows appear to be very sensitive to the choice of the model characteristics and therefore require a careful calibration of the parameterization representing the vegetation/atmosphere interface. In this paper, the micrometeorological data from the HAPEX-MOBILHY field experiment are used to calibrate an evapotranspiration parameterization scheme over three types of dense vegetation typical of western Europe. This parameterization is then used a 2D mesoscale model to investigate the atmospheric response to a discontinuity in vegetation type (cereal crop to conifer forest). The results show a significant circulation when the soil is moist, associated with substantial PBL modification, whereas only a negligible atmospheric response is obtained when the soil is dry in the conifer forest). The results show a .
Approximations to quasi-birth-and-death processes with infinite blocks

The numerical analysis of quasi-birth-and-death processes rests on the resolution of a matrix-quadratic equation for which efficient algorithms are known when the matrices have finite order, that is, when the number of phases is finite. In this paper we consider the case of infinitely many phases from the point of view of theoretical convergence of truncation and augmentation schemes, and we develop four different methods. Two methods rely on forced transitions to the boundary. In one of these methods, the transitions occur as a result of the truncation itself, while in the other method, they are artificially introduced so that the augmentation may be chosen to be as natural as possible. Two other methods rely on forced transitions within the same level. We conclude with a brief numerical illustration.
Heating of a Confined Plasma by Oscillating Electromagnetic Fields

There are two ways of heating a plasma confined by a strong axial magnetic field. In the first of these the electric field is parallel to the magnetic field, the situation that obtains in ohmic heating. In the second of these, the electric field is perpendicular to the main axial magnetic field. In this paper we consider the second case only and consider the electric field to be produced by an externally imposed oscillation of the axial field. This method of heating is often called magnetic pumping.It is found that as far as the heating of the plasma is concerned, there are four characteristic times which play a fundamental role. These four times are: (1) the collision time, (2) the period of the oscillating field, (3) the time of transit of a typical ion through the heating region, and (4) the cyclotron period of an ion. If these four characteristic times are all of comparable order, the theoretical analysis is exceedingly complex. Therefore, four cases were considered in which these were taken to be of .
Utility of hyperspectral imagers in the mining industry: Italy’s gypsum reserves

The mining industry is plagued with socioeconomic and safety roadblocks with not many solutions in the midst of a demanding market. As more and more geologic research using hyperspectral technology has been performed, along with an affordable price point for commercial use of hyperspectral technology, the benefits of hyperspectral imaging to the mining industry has become apparent. This study identifies the key areas of use for hyperspectral imaging in the mining industry through a case study of gypsum mine samples obtained from a mine in central Tuscany.
4C +01.30: An X-shaped Radio Source with a Quasar Nucleus

The nature of X-shaped radio sources is interesting because of their possible relation to black hole mergers or the processing of binary black holes. In this paper we report the discovery of a new X-shaped radio galaxy with a partially obscured quasar nucleus. We present a detailed study of the radio morphology and the optical image and spectrum from the Sloan Digital Sky Survey. The optical spectrum shows prominent broad Hα emission but very weak Hβ emission. We interpret the large Balmer decrement as due to internal reddening and determine that the intrinsic nucleus luminosity is in the quasar range.
How realistic are claims about the benefits of using digital technologies for GHG emissions mitigation?

While the direct environmental impacts of digital technologies are now well documented, it is often said that they could also help reduce greenhouse gas (GHG) emissions significantly in many domains such as transportation, building, manufacturing, agriculture, and energy. Assessing such claims is essential to avoid delaying alternative action or research. This also applies to related claims about how much GHG emissions existing digital technologies are already avoiding. In this paper, we point out critical issues related to these topics in the state of the art. First, most papers do not provide enough details on the scenarios underlying their evaluations: which hypotheses they are based on and why, and why specific scenarios are chosen as the baseline. This is a key point because it may lead to overestimating the current or potential benefits of digital solutions. Second, results are rarely discussed in the context of global strategies for GHG emissions reduction. These leaves open how the proposed technologies would fit into a realistic plan for meeting current GHG reduction goals. To overcome the underlined limitations, we propose a set of guidelines that all studies on digital solutions for mitigating GHG emissions should satisfy, point out overlooked research directions, and provide concrete examples and initial results for the specific case of carpooling.
Preparation and characterization of a drug carrier for hepatocellular carcinoma targeting

Asialoglycoprotein receptors distributing on the surface of hepatic parenchymal cells could specifically recognize galactose residues. Therefore, galactose residues can be applied in hepatocellar carcinoma targeted therapy through binding to the asialoglycoprotein receptors. A drug carrier containing of near infrared (NIR) fluorescence dye (MPA) and galactose was constructed by covalently conjugation process and named as GAL-MPA. The optical properties, cell viability, cell affinity and in vivo bio-distribution of this drug carrier were evaluated respectively. The results demonstrated that the drug carrier was provided with NIR fluorescence after conjugated with MPA. The low bio-toxicity and high hepatic cells affinity facilitated this drug carrier for in vivo biomedical application. Finally, the in vivo dynamic distribution of GAL-MPA confirmed this drug carrier was a promising candidate for tumor-targeting imaging and therapy.
Polarization properties of elliptical core non-hexagonal symmetry polymer photonic crystal fibre

In this paper, polarization properties and propagation characteristics of polymer photonic crystal fibres with elliptical core and non-hexagonal symmetry structure are investigated by using the full vectorial plane wave method. The results show that the birefringence of the fibre is induced by asymmetries of both the cladding and the core. Moreover, by adjusting the non-symmetrical ratio factor of cladding η from 0.4 to 1 in step 0.1, we find the optimized design parameters of the fibre with high birefringence and limited polarization mode dispersion, operating in a single mode regime at an appropriate wavelength range. The range of wavelength approaches the visible and near-infrared which is consistent with the communication windows of polymer optical fibres.
Location of Zeros of Chromatic and Related Polynomials of Graphs

Abstract We consider the location of zeros of four related classes of polynomials, one of which is the class of chromatic polynomials of graphs. All of these polynomials are generating functions of combinatorial interest. Extensive calculations indicate that these polynomials often have only real zeros, and we give a variety of theoretical results which begin to explain this phenomenon. In the course of the investigation we prove a number of interesting combinatorial identities and also give some new sufficient conditions for a polynomial to have only real zeros.
Bias effect on the growth of carbon nanotips using microwave plasma chemical vapor deposition

Carbon nanotips with a high-aspect ratio were directly grown on Pt films. Carbon nanotips grew up to 5.4 μm length and 64 nm diameter under a −120 V bias. Compared to the hollow structure of carbon nanotubes, transmission electron microscopy images indicate its solid body, which is made of graphite. Carbon nanotips possess good field emission characteristics, that is, a turn-on field of 1.5 V/μm and 761 μA/cm2 under 2.2 V/μm. The Pt films provide a good conduction path for electron transport from the cathode to the emission site and do not act as catalysts.
H α imaging polarimetry of the protoplanetary nebula M2-9

After correction for interstellar polarization, our Hα polarization map of the protoplanetary nebula M2-9 shows that a significant fraction of the emission-line radiation from the nebular lobes is scattered radiation originating in the central core. We find no evidence for a spatially extended illuminating source on scales of ≥ 1-2 arcsec. In order to explain our polarization results, we present a geometrical model for the system which has diametrically opposed cavities previously created in a pre-existing dusty envelope. The illumination of the cavity walls leads to the reflection nebula properties of M2-9. We find that the high-excitation emission-line knots, supposedly undergoing regular rotation about the major axis on a time-scale of decades, have not moved significantly since 1977
Sunspot Gyroresonance Emission at 17 GHz: A Statistical Study

We investigate the sunspot gyroresonance emission at 17GHz using the synoptic database of the Nobeyama Radioheliograph. Our statistical study is based on full disk observations obtained during the maximum of Cycle 22 (1992–94). We study the center-to-limb variation of the brightness and polarization of the sunspot radio emission and present some cases of polarization reversal. We find that the radio emission is most likely 3rd-harmonic gyroresonance emission arising from 2000 G fields in transition region, or low corona temperatures.