Miracle-dz/UniFAR-FTUs huggingface dataset:
Likelihood Function and Canonical Correlation Analysis of the Peña–Box Model

The Peña–Box model is a type of dynamic factor model whose factors try to capture the time-effect movements of a multiple time series. The Peña–Box model can be expressed as a vector autoregressive (VAR) model with constraints. This article derives the maximum likelihood estimates and the likelihood ratio test of the VAR model for Gaussian processes. Then a test statistic constructed by canonical correlation coefficients is presented and adjusted for conditional heteroscedasticity. Simulations confirm the validity of adjustments for conditional heteroscedasticity, and show that the proposed statistics perform better than the statistics used in the existing literature.
Structural and dielectric study of parylene C thin films

α, β, and γ relaxation mechanisms have been identified in semicrystalline (45% of crystallinity) parylene-C (–H2C–C6H3Cl–CH2–)n films. C–Cl bonds induce the β-relaxation and explain increase in the dielectric constant as the frequency decreases in usual temperatures of operation for devices incorporating parylene-C. At cryogenic temperature (<−20 °C), γ-relaxation is assigned to the local motions of phenyl groups. Both β and γ relaxation processes obey an Arrhenius law with activation energy Ea(β)=91.7 kJ/mole and Ea(γ)=8.68 kJ/mole. α-relaxation associated with cooperative segmental motions of the (–H2C–∅–CH2–)n chains is observed with a peak at 10−2 Hz for T=80 °C and follows a Vogel–Fulcher–Tamman–Hesse law.
The infrared coronal lines of recent novae

IR coronal line emissions are reported in the novae V1819 Cyg and V827 Her; high-resolution near-IR spectra of coronal line emission in the nova QU Vul have also been obtained, increasing the number of known IR coronal line novae from two to four. Each of the four is found to be characterized by approximately the same Si VI/Si VII line-intensity ratio, which indicates a common coronal-zone electron temperature of 300,000 K. The coronal-line novae are noted to possess a remarkably similar near-IR spectrum, suggesting that their coronal line emission will only occasionally be observed at optical wavelengths. 51 refs.
The SSBUV experiment wavelength scale and stability: 1988 to 1994

A solar backscatter ultraviolet experiment flies regularly on the Space Shuttle to help validate and maintain the calibrations of several satellite-borne stratospheric ozone monitoring instruments. The Shuttle Solar Backscatter Ultraviolet (SSBUV) programme incorporates multiple radiometric standards and redundant calibration checks which have allowed the tracking of long-term changes in the calibration of the SSBUV instrument to within 1% over six flights. The reduction of uncertainties in SSBUV wavelength calibration has recently been emphasized because of an increasing need to improve precision and accuracy. Therefore, selected solar spectral features are now used to monitor intra- and inter-flight changes in that wavelength calibration. The results of applying this technique to the six SSBUV Shuttle missions are presented, together with a comparison of these results with results from two traditional approaches in which laboratory and on-board spectral line sources, respectively, are used to determine and monitor the SSBUV wavelength scale. Long-term wavelength calibration change is less than 0,02 nm, and intra-flight wavelength change is 0,05 nm or less.
Imaging the electronic structure of valence orbitals in the XUV ionization of aligned molecules

We present measurements of photoelectron angular distributions (PADs) for the ionization of aligned CO2 molecules by an extreme ultraviolet laser pulse (17–45 eV) that is produced via high-harmonic generation, and that is polarized perpendicularly to the alignment laser axis. Differential PADs are recorded by taking the difference between two measurements for aligned and anti-aligned molecules. The results are compared with ab initio multi-channel R-matrix calculations, which are extended to include the computation of PADs. The calculations agree very well with the experiment, and are resolved with respect to the internal state of the ion and the polarization of the ionizing laser field relative to the molecular frame. For a sufficiently high, but experimentally achievable degree of alignment, the nodal structure of the molecular orbital becomes visible in the PAD.
Nonrandom percolation behavior of grain boundary networks in high-Tc superconductors

The grain boundary networks of tetragonal and orthorhombic superconductors are shown to be nonrandom through computer simulations of polycrystalline structures. For biaxially textured microstructures, the distribution of low-angle grain boundaries around triple junctions is measurably deviant from the expectations for a randomly constructed lattice. Percolation thresholds are calculated for the unhindered flow of superconducting current through a polycrystal, and are found to be significantly different from the standard random percolation threshold in two dimensions. These deviations are explained as a result of crystallographic constraints on the network topology.
Tunable plasmonic resonance arising from broken-symmetric silver nanobeads with dielectric cores

We investigate the plasmonic resonance modes and coupling effects of single silver nanobeads and silver nanobead dimers. Numerical investigation using the three-dimensional finite element method indicates that silver nanobeads exhibit two plasmonic resonances corresponding to the bonding and anti-bonding modes, respectively. The boundary symmetry on the inner and outer surfaces of the silver nanobeads can be broken by increasing the refractive indices of the cores filling the dielectric holes. It is shown that only the bonding mode can be found for low-refractive index cores, whereas both bonding and anti-bonding modes can be found for high-refractive index cores.
Adjusted Wald Confidence Interval for a Difference of Binomial Proportions Based on Paired Data

Adjusted Wald intervals for binomial proportions in one-sample and two-sample designs have been shown to perform about as well as the best available methods. The adjusted Wald intervals are easy to compute and have been incorporated into introductory statistics courses. An adjusted Wald interval for paired binomial proportions is proposed here and is shown to perform as well as the best available methods. A sample size planning formula is presented that should be useful in an introductory statistics course.
An adaptive mesh refinement method for solution of the transported PDF equation

This paper presents the results of an investigation into a possible alternative to Monte Carlo methods for solving the transported probability density function (PDF) equation for scalars (compositions). The method uses a finite‐volume approach combined with adaptive mesh refinement (AMR) in a multi‐dimensional compositional space. Comparisons are made between the new method and Monte Carlo solutions for analytical test cases involving the reaction of two or three chemical species. These tests demonstrate the potential of the new method in terms of both accuracy and run time. Additional test cases involving various models for molecular mixing were also conducted with similar conclusions. Copyright © 2009 John Wiley & Sons, Ltd.
Evolution of the Structure of Precipitation in Hurricane Allen (1980)

Abstract Reflectivity data from the airborne radar systems on board the three NOAA aircraft were gathered during six consecutive days in Hurricane Allen of 1980. The data have been used to specify the horizontal and vertical precipitation distribution within 111 km radius of the hurricane center. The evolution of the structure and intensity of the precipitation in the storm is described from representative time composite radar maps for seven research flights made during the 6-day period. The eyewall was characterized by a narrow ring (12–15 km wide) of intense reflectivity (42–47 dBZ) surrounding the center of the storm at a radius that varied in time from 12–40 km. The eyewall had steep radial gradients of reflectivity (4–5 dB km−1) and tilted radially outward in height. The rainbands were characterized by areas of enhanced reflectivity embedded in a region of stratiform rainfall that contained a distinct bright band at the height of the 0°C isotherm. The most striking changes in structure during the 6-d.
Thermoacoustic-wave equations for gas in a channel and a tube subject to temperature gradient

This paper develops a general theory for linear propagation of acoustic waves in a gas enclosed in a two-dimensional channel and in a circular tube subject to temperature gradient axially and extending infinitely. A ‘narrow-tube approximation’ is employed by assuming that a typical axial length is much longer than a span length, but no restriction on a thickness of thermoviscous diffusion layer is made. For each case, basic equations in this approximation are reduced to a spatially one-dimensional equation in terms of an excess pressure by making use of a method of Fourier transform. This equation, called a thermoacoustic-wave equation, is given in the form of an integro-differential equation due to memory by thermoviscous effects. Approximations of the equations for a short-time and a long-time behaviour from an initial state are discussed based on the Deborah number and the Reynolds number. It is shown that the short-time behaviour is well approximated by the equation derived previously by the boundary-layer theory, while the long-time behaviour is described by new diffusion equations. It is revealed that if the diffusion layer is thicker than the span length, the thermoviscous effects give rise to not only diffusion but also wave propagation by combined action with temperature gradient, and that negative diffusion may occur if the gradient is steep.
Dislocation dynamics during the growth of silicon ribbon

The thermal viscoplastic stresses and the dislocation densities in silicon ribbon are computed for an axially changing thermal profile by using an iterative finite difference method. A material constitutive equation (Haasen–Sumino model) which involves an internal variable (mobile dislocation density) is used. The results are interpreted as showing that there is a maximum width of silicon ribbon that can be grown when viscoplasticity and dislocations are considered. This maximum width limitation does not exist if the material behavior is elastic.
The Simplified Component Technique: An Alternative to Rotated Principal Components

Abstract It is fairly common, following a principal component analysis, to rotate components in order to simplify their structure. Here, we propose an alternative to this two-stage procedure which involves only one stage and combines the objectives of variance maximization and simplification. It is shown, using examples, that the new technique can provide alternative ways of interpreting a dataset. Some properties of the technique are investigated using a simulation study.
The Multivariate Black & Scholes Market: Conditions for Completeness and No-Arbitrage

In order to price multivariate derivatives, there is need for a multivariate stock price model. To keep the simplicity and attractiveness of the one-dimensional Black & Scholes model, one often considers a multivariate model where each individual stock follows a Black & Scholes model, but the underlying Brownian motions might be correlated. Although the classical one-dimensional Black & Scholes model is always arbitrage-free and complete, this statement does not hold true in a multivariate setting. In this paper, we derive conditions under which the the multivariate Black & Scholes model is arbitrage-free and complete.
Unified Model for Superconductivity in Graphite Intercalation Compounds: Prediction of Optimum Tc and Suggestion for Its Realization

Based on the model that was successfully applied to KC 8 , RbC 8 , and CsC 8 in 1982, we have calculated the superconducting transition temperature T c for CaC 6 and YbC 6 to find that the same model reproduces the observed T c in those compounds as well, indicating that it is a unified model for superconductivity in the graphite intercalation compounds with T c ranging over three orders of magnitude. Further enhancement of T c well beyond 10 K is also predicted.
NANOMETER-SCALE IMAGING OF LATTICE DEFORMATION WITH TRANSMISSION ELECTRON MICROGRAPH

We demonstrate a new method of imaging crystal lattice strain with spatial resolution on the nanometer scale. The method, Fourier transform mapping (FTM), is based on the mapping of spot positions in local Fourier-transformed images from a transmission electron microscope image. Lattice deformation caused by island formation due to strained epitaxial growth is imaged and the relief of the strain in the lateral direction, as well as that in the normal direction, is clearly visible in the lattice-deformation image.
A rain water infiltration model with unilateral boundary condition: qualitative analysis and numerical simulations

We present a rigorous mathematical treatment of a model describing rain water infiltration through the vadose zone in case of runoff of the excess water. The main feature of the mathematical problem emerging from the model lies on the boundary condition on the ground surface which is in the form of a unilateral constraint. Existence and uniqueness of a weak solution is proved under general assumptions. We present also the results of a numerical study comparing the proposed model with other models which approach in a different way the rain water infiltration problem. Copyright © 2006 John Wiley & Sons, Ltd.
A new improved local Chan-Vese model

Based on the local image information, we propose a new improved local active contour model to segment inhomogeneous images. The level set evolution equation of the proposed model which is different from improved Chan- Vese (ICV) model and local Chan-Vese (LCV) model is ordinary differential equation. Without mean curvature and other complicate difference items, the implementation becomes simpler by employing a finite difference scheme, thus the efficiency of global segmentation is dramatically improved. Experimental results on synthetic images as well as real medical images are shown in the paper to demonstrate the segmentation accuracy, efficiency and robustness of the proposed method.
Refined bounds for the eigenvalues of the Klein-Gordon operator

The aim of this article is twofold. First we establish sharper lower bounds for the sums of eigenvalues of ( − Δ) 1 2 | D , the Klein-Gordon operator restricted to a bounded domain D ⊂ R d , than the bounds obtained in works by E. Harrell; S. Yıldırım Yolcu; and G. Wei, H. Sun, and L. Zeng. Then we study upper bounds for the sums of negative powers of the eigenvalues of ( − Δ) 12 | D .
Scattering cross sections for composite rough surfaces using the unified full wave approach

The full wave approach is used to derive a unified formulation for the like and cross polarized scattering cross sections of composite rough surfaces for all angles of incidence. Earlier solutions for electromagnetic scattering by composite random rough surfaces are based on two-scale models of the rough surface. Thus, on applying a hybrid approach physical optics theory is used to account for specular scattering associated with a filtered surface (consisting of the large sonic spectral components of the surface) while perturbation theory is used to account for Bragg scattering associated with the surface consisting of the small scale spectral components. Since the full wave approach accounts for both specular point scattering and Bragg scattering in a self-consistent manner, the two-scale model of the rough surface is not adopted in this work. These unified full wave solutions are compared with the earlier solutions and the simplifying assumptions that are common to all the earlier solutions are examined. It is shown that while the full wave solutions for the like polarized scattering cross sections based on the two-scale model are in reasonably good agreement with the unified full wave solutions, the two solutions for the cross polarized cross sections differ very significantly.
The influence of static stability on the effective roughness lengths for momentum and heat transfer

The area-averaged properties of the planetary boundary layer over heterogeneous terrain are considered. Previous studies which dealt with the average momentum transfer properties in neutral static stability conditions are extended to include the influence of stratification and also area-averaged properties for heat transfer. Results from numerical simulations demonstrate the utility of values of effective roughness length for both momentum and heat transfer. A heuristic model is found to show good agreement with the numerical simulations and to provide a simple method for estimating these roughness lengths for use in boundary-layer parametrization. Significant anomalies in the surface heat fluxes, particularly those of sensible heat, accompanied the decrease in the sea ice concentration. Substantial atmospheric warming was simulated over and in the vicinity of areas in which leads were considered. In all but one experiment there were anomalous easterlies between about 40 and 60°S with westerly anomalies further to the south. The surface pressure at high latitudes appears to change in a consistent fashion with the fraction of open water, with the largest changes occurring in the Weddell and near the Ross Seas. Some of the feedbacks which may enhance the responses here, but which are not included in our model, are discussed.
Super multi-view display with 128 viewpoints and viewpoint formation

A super multi-view (SMV) display and a high-density directional (HDD) display have both been proposed as natural three-dimensional displays that would solve the accommodation-vergence conflict and offer smooth motion parallax. Previously, a multiple projection system was employed in the construction of a HDD display. In this study, a multiple projection system is modified to serve as a SMV display. A lens is attached to the display screen. The screen lens images an aperture array in the multiple projection system at a fixed distance from the screen, and the image of the aperture array generates dense viewpoints. A 128-direction HDD display having ~QVGA resolution is employed to construct a 128-view SMV display. Fresnel lenses with focal lengths of 500 mm, 600 mm, 1,000 mm, 1,200 mm, and 1,500 mm were used as the screen lens. When the observation distance differs from the distance at which viewpoints are generated, a retinal image is formed by an assembly of plural parallax images. The dependency of image quality on observation distance is evaluated. Subjective evaluation shows that a Fresnel lens with a long focal length, i.e., 1,200 mm, gives better image quality for a wider observation distance range.
Infrared Absorption and Emission Spectra of Hydrogenated Amorphous Carbon Prepared in the Presence of Oxygen, Nitrogen, Ammonia, and Carbon Monoxide

The formation of carbonaceous condensates in the atmospheres of asymptotic giant branch (AGB) carbon stars and in the nebulae of post-AGB objects occurs in a chemical environment that also contains oxygen and nitrogen. The extent of incorporation of chemical groups containing these elements in carbonaceous solids will depend on the ratios C/O and C/N. The presence of chemical groups containing O and N can have a significant effect on the infrared spectrum of this material through the introduction of new absorption and emission features and by perturbing spectral lines arising from CH and other hydrocarbon groups. To simulate some aspects of this chemistry, we have prepared samples of hydrogenated amorphous carbon (HAC) containing these elements by laser ablation of graphite in mixed H2/N2, H2/O2, and H2/CO gases and in NH3. Absorption and emission spectra are reported for these materials in the 2.5-20 μm region. We find that the inclusion of oxygen has a profound effect on both 3.4 μm and longer wavelength absorption in HAC even at low concentration. Condensation of HAC in the presence of N2, CO, and NH3 produces changes in the profile and relative intensity of components of the 3.4 μm CH2, 3 hydrocarbon band, but some of these effects can be reversed by heating to higher temperature. We find that the condensation of a crystalline diamond component is greatly facilitated in the presence of O2 or NH3. A number of sharp spectral features attributable to diamond have been observed in these spectra.
Renormalized perturbation theories of Anderson localization: Self‐consistent two‐particle vertices

We study effects of quantum coherence due to scatterings of electrons on impurities on two‐particle vertex functions. We use the diagrammatic perturbation expansion in the impurity potential and analyze possible ways how to introduce renormalizations on the two‐particle level. We discuss the differences between the low‐dimensional self‐consistent theory of Vollhardt and Wölfle and the high‐dimensional one of Janiš and Kolorenč. Finally we demonstrate, using the latter approach, the emergence of the localized phase in the Falicov‐Kimball model.
Nonlinear Zakharov–Kuznetsov equation for obliquely propagating two-dimensional ion-acoustic solitary waves in a relativistic, rotating magnetized electron-positron-ion plasma

The purpose of this work is to investigate the linear and nonlinear properties of the ion-acoustic waves (IAW), propagating obliquely to an external magnetic field in a weakly relativistic, rotating, and magnetized electron-positron-ion plasma. The Zakharov–Kuznetsov equation is derived by employing the reductive perturbation technique for this wave in the nonlinear regime. This equation admits the solitary wave solution. The amplitude and width of this solitary wave have been discussed with the effects of obliqueness, relativity, ion temperature, positron concentration, magnetic field, and rotation of the plasma and it is observed that for IAW these parameters affect the propagation properties of solitary waves and these plasmas behave differently from the simple electron-ion plasmas. Likewise, the current density and electric field of these waves are investigated for their dependence on the above-mentioned parameters.
Multiple testing in ordinal data models

: Consider an R × C contingencytable in which the categoriesare ordered. Multiple testing of the hypotheses that each local odds ratio is one is carried out. The methodology to perform the multiple tests is an exten- sion of the MRDSS method of Chen, Cohen, and Sackrowitz (2009). The MRDSS method extends the MRD method of Cohen, Sackrowitz, and Xu (2009) by adding a screen stage and a sign stage to MRD. The MRDSS method as well as the extension here is admissible and consistent. Both Fisher-type statistics and Chi-square statistics are used. Examples and a simulation study are included.
BIASES OF ESTIMATORS IN MULTIVARIATE NON‐GAUSSIAN AUTOREGRESSIONS

Expressions for the bias of the least-squares and modified Yule-Walker estimators in a correctly specified multivariate autoregression of arbitrary order are obtained without assuming that the innovations are Gaussian. Instead, the innovations are assumed to form a martingale difference sequence which is stationary up to sixth order and which has finite sixth moments. The errors in the expressions are shown to be O(n-3/2), as the sample size n under some moment conditions. The expressions obtained are the same in the Gaussian and non-Gaussian cases.