Miracle-dz/UniFAR-FTUs huggingface dataset:
Inverse estimation of distributed roughness coefficients in vegetated flooded rivers

ABSTRACT This paper describes data assimilation for estimating bed roughness factor due to vegetation in natural rivers. An adjoint shallow-water model was developed for variational data assimilation. Optimal values for distributed bed roughness coefficients were determined using a quasi-Newtonian method with flow and adjoint variables. The data assimilation technique was applied to inverse estimation of the distributed coefficients in the lower reaches of the Asahi River in Japan during flooding in 2011. For practical use, the assimilated data comprised water levels measured along the river at regular time intervals. Results show that the magnitude of each coefficient distributed over targeted subregions was reasonably consistent with the vegetation species established in the corresponding subregion, considering characteristic values of vegetation related to the flow resistance.
Highly nonlinear tellurite microstructured fibers for broadband wavelength conversion and flattened supercontinuum generation

We demonstrate four-wave mixing based broadband (>68 nm) wavelength conversion and flattened supercontinuum generation spanning from 900 to 2800 nm in a 36-cm long tellurite microstructured fiber which has a high nonlinearity. By reducing the size of air holes of the tellurite microstructured fibers, single mode propagation and small dispersion slope are obtained without the propagation loss enhancement. Our results show that chromatic-dispersion controlled tellurite microstructured fibers are promising candidates for nonlinear applications.
Raindrop Size Distribution in Different Climatic Regimes from Disdrometer and Dual-Polarized Radar Analysis

Abstract The application of polarimetric radar data to the retrieval of raindrop size distribution parameters and rain rate in samples of convective and stratiform rain types is presented. Data from the Colorado State University (CSU), CHILL, NCAR S-band polarimetric (S-Pol), and NASA Kwajalein radars are analyzed for the statistics and functional relation of these parameters with rain rate. Surface drop size distribution measurements using two different disdrometers (2D video and RD-69) from a number of climatic regimes are analyzed and compared with the radar retrievals in a statistical and functional approach. The composite statistics based on disdrometer and radar retrievals suggest that, on average, the two parameters (generalized intercept and median volume diameter) for stratiform rain distributions lie on a straight line with negative slope, which appears to be consistent with variations in the microphysics of stratiform precipitation (melting of larger, dry snow particles versus smaller, rimed ic.
Selection of acoustic features for speaker identification

The aim of this study was to determine a set of acoustic features in the speech signal that are effective for the identification of a speaker. The investigation examined a large number of theoretically attractive features. The analysis technique of linear prediction was incorporated to examine features that were previously ignored because their measurement was either too time consuming or not easily amenable to automatic measurement. A novel probability of error criterion was used to determine the the relative merits of the features. The experimental data base was collected over a 3\frac{1}{2} year period and afforded the oportunity to investigate the variation over time of the measurements. The measurements that were found to be the most important were the value of the second resonance (around 1000 Hz) in /n/, the value of the third or fourth resonance (1700-2000 Hz) in /m/ the values of the second, third and fourth formant frequencies in vowels, and the average fundamental frequency of the speaker. A speaker identification experiment using only the best five features was performed. The test data consisted of the multisession data of 11 speakers, and the test data was kept independent of the design data. One error was made in the identification of these speakers for 320 separate identification experiments.
Linear Estimators and Radonifying Operators

We consider the problem of estimating a signal Y with values in a Banach space based on the observation X with values in another Banach space given their joint Gaussian distribution. Linear estimators are defined to be measurable linear transformations. A characterization of measurable linear transformations with respect to a Gaussian measure by radonifying operators is established. The Bayes estimator ${\bf E}(Y|X)$ is shown to be a measurable linear transformation and the associated radonifying operator is derived.
Far Outer Galaxy H II Regions

We have made a multifrequency (6, 3.6, and 2 cm), high-resolution (3"-6"), radio continuum survey of IRAS selected sources from the catalogue of Wouterloot & Brand (1989) to search for and study H II regions in the far outer Galaxy. We identified 31 sources in this catalog with well determined galactocentric distances, and with R approx. greater than 15 kpc and L(sub FIR) approx.greater than 10(exp 4) solar luminosity, indicating the presence of high-mass star-formation. We have observed 11 of these sources with the Very Large Array (VLA). We observed the sources at 6 and 2 cm using "scaled arrays", making possible a direct and reliable comparison of the data at these two wavelengths for the determination of spectral indices. We detected a total of 12 radio sources, of which 10 have spectral indices consistent with optically-thin free-free emission from H II regions. Combined with previous VLA observations by other investigators, we have data on a total of 15 H II regions at galactocentric distances of 15 to 18.2kpc, among the most remote H II regions found in our Galaxy. The sizes of the H II regions range from approx. less than 0.10 to 2.3 pc. Using the measured fluxes and sizes, we determine the electron densities, emission measures, and excitation parameters of the H II regions, as well as the fluxes of Lyman continuum photons needed to keep the nebulae ionized. The sizes and electron densities are consistent with most of the sources detected in this survey being compact or ultracompact H II regions. Seven of the fifteen H II regions have sizes approx. less than 0.20 pc. Assuming simple pressure-driven expansion of the H II regions, these sizes indicate ages approx. less than 5 x 10(exp 4) yr, or only 1% of the lifetime of an O star, which implies an unlikely overabundance of O stars in the outer Galaxy. Thus, the large number of compact H II regions suggests that the time these regions spend in a compact phase must be much longer than their dynamical expansion times. Five of the fifteen H II regions have cometary shapes; the remainder are spherical or unresolved. Comparison of the radio continuum data with molecular line maps suggests that the cometary shape of the two H II regions in S 127 may be due to pressure confinement of the expanding ionized gas, as in the "blister" or "champagne flow" models of H II regions. Comparison of the radio continuum data with the IRAS far-infrared data indicates that the five most luminous H II regions are consistent with a single 0 or B star exciting a dust-free H II region. Subject headings: stars: formation - ISM: H II regions - ISM: individual objects: S 127 radio continuum: interstellar
A New Approach to ARMA Modeling.

In recent years the Box-Jenkins method has become a popular technique for forecasting future behavior of a time series. Once adecruate computer packages are available for most purposes. un fortunately the problem of determining the appropriate forecast model has, for models of any complexity, been one of the major stumbling blocks to the user of this method. In this paper a satisfactory solution to that problem is obtained and it is demonstrated by numerous examples how this greatly enlarges the class of data sets which can be adequately modeled by autoregressive-moving average models. This new approach is sufficiently unequivocal that most users will find it easy to implement.
Quantum discord of the two-atom system in non-Markovian environments

The quantum discord of the two-atom system, which is in two independent Lorentzian reservoirs and in two independent Ohmic reservoirs with the Lorentz–Drude cutoff function, respectively, and the reservoirs are at zero temperature, is studied by applying the time-convolutionless master-equation method. We find that the quantum discord of the two-atom system is dependent on the characteristics of non-Markovian environments. The results show that the quantum discord can be effectively protected not only in Lorentzian reservoirs, but also in ohmic reservoirs with the Lorentz–Drude cutoff function. Finally, the physical interpretations for these results are given via the correlation function.
Structural similarity micro clustering algorithm for local outliers and hubs using dynamic minimum spanning tree

Abstract Clustering is a process of discovering groups of objects such that the objects of the same group are similar, and objects belonging to different groups are dissimilar. Minimum spanning tree based clustering algorithm is capable of detecting clusters with irregular boundaries. Many algorithms find clusters by maximizing the number of intra-cluster edges. While such algorithms find useful and interesting structures, they tend to fail to identify and isolate two kinds of vertices that play special roles-vertices that bridge clusters (hubs) and vertices that are marginally connected to clusters (outliers). Identifying hubs is useful for applications such as viral marketing and epidemiology since hubs are responsible for spreading ideas and disease. In this paper we propose a novel algorithm called Structural Similarity Micro Clustering Algorithm for Local outliers and hubs using Dynamic Minimum Spanning Tree (SSMCALOHDMST), which detect clusters, outliers and hubs in data set. The algorithm partition the dataset into optimal number of clusters. The algorithm uses a new cluster validation criterion based on the geometric property of data partition of the data set in order to find the proper number of clusters. The algorithm works in two phases. The first phase of the algorithm creates optimal number of clusters, where as the second phase of the algorithm detect outliers and hubs.
Magnetogravitational instability of a Vlasov plasma

A complete derivation of the moment equations of a Vlasov plasma has been presented separately for the three density domains, namely the high-density regime (b→0), the moderate-density regime [bϵ ≃ O(1)] and the low-density regime [bϵ2 ≃ O(1)] with b as the ratio of Alfvén velocity to light velocity and ϵ = a/L where a is the ion Larmor radius and L, the characteristic length of the system. These moment equations are then employed to investigate the effect of finite β (= particle pressure/magnetic pressure) on gravitational flute instability of a non-uniform plasma. It is shown that the effect of finite β is one of stabilization.
Entanglement-induced collective many-body interference

Entanglement and interference are both hallmark effects of quantum physics. Particularly rich dynamics arise when multiple (at least partially) indistinguishable particles are subjected to either of these phenomena. By combining both entanglement and many-particle interference, we propose an interferometric setting through which N-particle interference can be observed, while any interference of lower orders is strictly suppressed. We experimentally demonstrate this effect in a four-photon interferometer, where the interference is nonlocal, in principle, as only pairs of photons interfere at two separate and independent beam splitters. A joint detection of all four photons identifies a high-visibility interference pattern varying as a function of their collective four-particle phase, a genuine four-body property.
Thermodynamic analysis of an integrated gasification combined cycle power plant: effect of nitrogen supply on system performance

A comprehensive thermodynamic analysis of a conceptual integrated coal gasification combined cycle power plant is presented. Energy and exergy efficiencies and exergy destructions of each sub-unit are calculated. The effect of nitrogen, which is supplied from the Air Separation Unit (ASU) of the gasification unit to the combustion chamber of the gas turbine (GT) cycle, on system performance is parametrically studied. The energy efficiency of the system is found to be 41%, while the exergy efficiency for the integrated gasification combined cycle power plant is 37%. The results also demonstrate that the nitrogen supply enhances the system performance. Additional parametric studies are presented for various operating conditions: nitrogen supply ratio, pressure ratio, and steam turbine inlet temperatures.
Well-to-well non-uniformity in InGaN/GaN multiple quantum wells characterized by capacitance-voltage measurement with additional laser illumination

We experimentally investigated well-to-well non-uniformity in InGaN/GaN multiple quantum well (MQW) structures by using capacitance-voltage measurements with additional laser illumination. By varying the illuminating power of the resonant excitation, well-to-well non-uniformity through the MQWs was clearly revealed. The quantum wells (QWs) close to the n-GaN side show higher carrier accumulations and larger position shift as the excitation power is increased, relative to the p-side QWs. Both results were attributed to the existence of stronger piezoelectric fields in the n-side QWs induced by subsequent partial relaxation of strain through the MQWs.
FPGA‐based adaptive dynamic sliding‐mode neural control for a brushless DC motor

In the adaptive neural control design, since the number of hidden neurons is finite for real‐time applications, the approximation errors introduced by the neural network cannot be inevitable. To ensure the stability of the adaptive neural control system, a switching compensator is designed to dispel the approximation error. However, it will lead to substantial chattering in the control effort. In this paper, an adaptive dynamic sliding‐mode neural control (ADSNC) system composed of a neural controller and a fuzzy compensator is proposed to tackle this problem. The neural controller, using a radial basis function neural network, is the main controller and the fuzzy compensator is designed to eliminate the approximation error introduced by the neural controller. Moreover, a proportional‐integral‐type adaptation learning algorithm is developed based on the Lyapunov function; thus not only the system stability can be guaranteed but also the convergence of the tracking error and controller parameters can speed up. Finally, the proposed ADSNC system is implemented based on a field programmable gate array chip for low‐cost and high‐performance industrial applications and is applied to control a brushless DC (BLDC) motor to show its effectiveness. The experimental results demonstrate the proposed ADSNC scheme can achieve favorable control performance without encountering chattering phenomena.
Global well-posedness of weak solutions for the Lagrangian averaged Navier-Stokes equations on bounded domains

In this paper, we study the Lagrangian averaged Navier-Stokes (LANS-$\alpha$) equations on bounded domains. The LANS-$\alpha$ equations are able to accurately reproduce the large-scale motion (at scales larger than $\alpha >0$) of the Navier-Stokes equations while filtering or averaging over the motion of the fluid at scales smaller than α, an a priori fixed spatial scale. We prove the global well-posedness of weak $H^1$ solutions for the case of no-slip boundary conditions in three dimensions, generalizing the periodic-box results of [8]. We make use of the new formulation of the LANS-$\alpha$ equations on bounded domains given in [20] and [14], which reveals the additional boundary conditions necessary to obtain well-posedness. The uniform estimates yield global attractors; the bound for the dimension of the global attractor in 3D exactly follows the periodic box case of [8]. In 2D, our bound is $\alpha$-independent and is similar to the bound for the global attractor for the 2D Navier-Stokes equations.
Scene illuminant estimation: Past, present, and future

This article addresses the problem of colour constancy: how a visual system is able to ensure that the colours it perceives remain stable, regardless of the prevailing scene illuminant. My aim is first to summarize and review the most important theoretical advances that have been made in this field. Second, I present a comparative analysis of algorithm performance that we use as the basis of a discussion of the current state of colour constancy research and of the important issues that future research in this field should address. Finally, I highlight some areas of recent research that are important in the context of further improving the performance of colour constancy algorithms. © 2006 Wiley Periodicals, Inc. Col Res Appl, 31, 303–314, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20226
Color Image Super-Resolution Reconstruction Based on Sparse Representation

This paper proposes a YUV color image super-resolution reconstruction algorithm based on sparse representation. The R, G, B components of color image are highly correlated, three-channel super-resolution independent reconstruction will lead to color distortion, so in this paper the color image is firstly converted to the Y, U, V three channels, and then super-resolution reconstruction. For choosing the regularization parameter, this paper proposes an adaptive regularization parameter method; it has a good inhibitory effect on image noise and adaptive super-resolution reconstruction of color images. The results of experiment show that the proposed algorithm has a better PSNR, compared with bicubic interpolation method and sparse representation. The adaptive super-resolution reconstruction can further improve the quality of the reconstructed image and the method is robust to image noise.
Topographic stress parameterization in a quasi-geostrophic barotropic model

The physical basis for parameterizing topographic stress due to unresolved eddies is examined in a quasi-geostrophic barotropic model. Topographic stress parameterization is shown to represent two effects of eddies: attraction of the flow to a statistical equilibrium featuring topographically correlated mean currents, and dissipation of potential enstrophy. Performance is evaluated by comparing parameterized low-resolution models with explicit high-resolution models.
Carrier migration in structures with InAs quantum dots

A spectrally and spatially resolved investigation of emission from InAs/GaInAs quantum dots is performed using confocal photoluminescence. Structures investigated included a single layer of InAs dots embedded in a Ga0.85In0. 15As quantum well and InAs dots embedded directly in GaAs. Excitation is performed at different wavelengths to provide selective excitation of either the quantum well or both the well and GaAs barrier. No noticeable lateral migration is observed under 900 nm wavelength pumping generating carriers only inside the quantum well. This is an indication that the diffusion of excess carriers is strongly suppressed by capture into dots. When GaAs surrounding material is also excited, the migration of excitation power occurs over 1.65 μm at the ground state of the quantum dots and 1.2 μm at the first-excited state. Saturation of the ground, first-, and second-excited state bands, when the carriers are generated only in quantum well, is also studied.
Mid-infrared Q-switched Er:YAG laser for medical applications

The 2.94 μm Er:YAG laser Q-switched mechanically by a rotating mirror was developed. The laser generated pulses of 30 mJ energy and duration below 290 ns, which corresponds to over 100 kW peak power. It operated at the repetition rate of up to 25 Hz. To our knowledge it is the most powerful erbium laser operating at so high repetition rate. The developed laser can be successfully applied in medicine – e.g. in microsurgery of soft biological tissues.
CD-SAXS measurements using laboratory-based and synchrotron-based instruments

Critical dimension small angle X-ray scattering (CD-SAXS) is a metrology platform capable of measuring the average cross section and line width roughness (LWR) with a sub-nm precision in test patterns with line widths ranging from 10 to 500 nm. The X-ray diffraction intensities from a collimated X-ray beam of sub-Angstrom wavelength were collected and analyzed to determine line width, pitch, sidewall angle, LWR, and others structural parameters. The capabilities of lab-scale and synchrotron-based CD-SAXS tools for LWR characterization were tested by measuring a set of identical patterns with designed roughness amplitude and frequency. These test patterns were fabricated using EUV lithography with sub-50 nm linewidths. To compensate for the limited photon flux from the lab-based X-ray source, the incident beam of the lab system was collimated to a less extent than the synchrotron beam-based tool. Consequently, additional desmearing is needed to extract information from data obtained from lab-based equipment. We report the weighted nonlinear least-squares algorithm developed for this purpose, in addiiton to a comparison between the results obtained from our lab system and the synchrotron beam-based tool.
Confidence Intervals and F Tests for Intraclass Correlations Based on Three-Way Random Effects Models

This article gives equations for computing confidence interval estimates and conducting F tests for intraclass correlation coefficients (ICCs) defined using three-way random effects models for crossed and nested designs. The estimates and tests employ mean squares from analyses of variance. The equations are generalized so that data from an initial pilot study (G study) can be used to prophesy the confidence limits for ICCs in data with more or fewer factor levels. Equations also are included for determining the optimal number of factor levels to use in a design that will offer confidence of 1-[. alpha] that the population ICC is equal to or exceeds a fixed lower limit.
Resonance magnetoelectric interactions in an asymmetric ferromagnetic-ferroelectric layered structure

Strain mediated magnetoelectric (ME) interactions have been investigated in a sample consisting of oppositely poled lead zirconate titanate (PZT) and asymmetric magnetostrictive layers. A thin layer of Ni with negative magnetostriction and amorphous ferromagnetic Metglas with positive magnetostriction are bonded to the PZT layers. It is shown that the magnetic layers facilitate effective excitation of bending oscillations in the structure, whereas the use of oppositely poled PZT layers results in an increase in the ME voltage at the bending resonance frequency, suppression of the voltage at the longitudinal electromechanical resonance frequency, and cancellation of thermal fluctuation in the voltage. The ME voltage coefficient at resonance is 18 V/(cm Oe); that is an order of magnitude higher than the value measured for a Ni–PZT bilayer of similar dimensions. Theoretical estimates of the ME voltage and resonance frequency are in good agreement with the data.