Miracle-dz/UniFAR-FTUs huggingface dataset:
Unequally protected packet transmission of SPIHT-compressed images

In combination with the discrete wavelet transform (DWT), set partitioning in hierarchical trees (SPIHT) is one of the most renowned techniques for image compression. One problem with SPIHT, however, is that its decoding can be extremely sensitive to errors in its embedded bit stream. In this paper, we address the issue of transmitting SPIHTencoded images in packets via erasure channels, wherein each received packet is either error-free or totally discarded. In our scheme, the original SPIHT code sequence is packetized (into two types: critical packet (CP) and refinement packet (RP)). Those packets are then allocated with different diversity orders for unequal error protection (UEP) so that the decoded image is expected to attain the highest signal-to-noise ratio (SNR) at the receiver. Simulations show that the proposed scheme significantly improves the decoded images as compared to the case of no diversity allocation and the case of not distinguishing between CP and RP.
Asymptotic Expansion of the Non Null Distribution of the Two-Sample t-Statistic Under Non Normality with Application in Power Comparison

This article studies the non null distribution of the two-sample t-statistic, or Welch statistic, under non normality. The asymptotic expansion of the non null distribution is derived up to n −1, where n is the pooled sample size, under general conditions. It is used to compare the power with that obtained by normal theory method. A simple technique is recommended to achieve more power through a monotone transformation in practice.
Convective instability when the temperature gradient and rotation vector are oblique to gravity. I. Fluids without diffusion

Abstract We carry out a linear stability analysis of fluid layers under uniform rotation which possess both vertical and horizontal temperature gradients. In order to represent vnrious latitudes with these plane parallel layers we use a rotation vector which is generally oblique to gravity. We consider ideal fiuids without diffusion within a Boussinesq approximation. This simplified configuration is used to assess the preferred convective modes as a function of latitude on a planet like Jupiter. The tilted rotation vector introduces a preference for roll-like disturbanas. with north-south orientations, while the horizontal temperature gradient produces a thermal wind shear which favors convective rolls oriented parallel to the flow in an east-west direction. With both these effects present we find that the horizontal ternperature gradient needed to produce a preference for the axisymmetric or east-west rolls increases with increasing rotation rate and decreasing latitude. The results also indicate that sh.
Convergence of a numerical scheme for SPDEs with correlated noise and global Lipschitz coefficients

The aim of this paper is to investigate the pathwise numerical solution of semilinear parabolic stochastic partial differential equations (SPDEs) with colored noise instead of the usual space–time white noise. We estimate the numerical solution in the L∞ topology by a method that takes advantages of the smoothing effect of the dominant linear operator. We consider the case the covariance operator of the forcing does not necessarily commute with the linear operator of the SPDE because of the fact that the Brownian motions are not necessarily independent. We show convergence of this method, and numerical examples give insight into the reliability of the theoretical study. Copyright © 2015 John Wiley & Sons, Ltd.
A Modular Approach To Assess Em Coupling Into Housings Through Small Apertures

—The coupling into cavities through apertures depends on several parameters as the size and shape of the cavity, position and size of the apertures, and the incident field. Amongst these, the position of the aperture on a cavity wall is of major importance for a given cavity. We present a modular method to efficiently compute the coupling even for various configurations by separating interior and exterior and using in each domain the most efficient method. Whereas the coupling is computed for small apertures, the method remains applicable to larger apertures. An exemplary computation of the coupling to strip type objects inside a cavity through an aperture at four characteristic locations shows the applicability of the method and the large influence of the aperture position on the electromagnetic field inside the cavity.
Atmospheric absorption in the atmosphere up to 160 km

This paper describes new algorithms, not previously available, for predicting atmospheric absorption of sound at high altitudes. A basis for estimating atmospheric absorption up to 160 km is described. The estimated values at altitudes above 90 km must be considered as only approximate due to uncertainties about the composition of the atmosphere above 90 km and simplifying assumptions. At high altitudes, classical and rotational relaxation absorption are dominant, as opposed to absorption by molecular vibrational relaxation that is the principle atmospheric absorption loss mechanism for primary sonic booms propagating downward from a cruising supersonic aircraft. Classical and rotational relaxation absorption varies inversely with atmospheric pressure, thus increasing in magnitude at high altitudes as atmospheric pressure falls. However, classical and rotational losses also relax at the high values of frequency/pressure reached at high altitudes and thus, for audio and infrasonic frequencies, begin to dec.
Excess electron transport and delayed muonium formation in condensed rare gases

Experimental studies of excess electron transport in solid and liquid phases of Ne and Ar are presented and compared with those for He. The technique of muon spin relaxation in frequently reversed electric fields was usedto study the phenomenon of delayed muonium formation, whereby excess electrons liberated in the μ + ionization track converge upon the positive muons and form μ + e - atoms. This process is shown to be crucially dependent upon the electron's interaction with its environment (i.e., whether it occupies the conduction band or becomes localized) and upon its mobility in these states. The characteristic lengths involved are 10 - 6 to 10 - 4 cm; the characteristic times range from nanoseconds to tens of microseconds. Such a microscopic length scale sometimes enables the electron to spend its entire free lifetime in a state which may not be detected by conventional macroscopic techniques. The end-of-track processes are compared in (i) liquid and solid helium (where the electron is known to be localized in a bubble in the liquid phase and is thought to behave in a similar manner in the solid); (ii) liquid and solid neon (where both localized and bandlike electrons are found in the liquid phase while most are delocalized in the solid); and (iii) liquid and solid argon (where most electrons are bandlike in both phases). This scaling from light to heavy rare gases enables us to demonstrate new features of excess electron localization on the microscopic scale and provides insight into the structure of the end of the muon track in condensed rare gases.
The Equilibrium Distribution for a Clocked Buffered Switch

A 2-by-2 buffered switch is the basic element of certain parallel data-processing networks. For a switch fed by two independent Bernoulli input streams, we find the joint distribution of the number of messages waiting in the two buffers at equilibrium, in the form of a bivariate generating function. The derivation uses complex-variable techniques developed by Kingman and by Flatto and McKean for the “shortest queue problem. ” A number of asymptotic results are given, the principal one being the variance of the total number of waiting messages in the heavy-traffic limit.
Nonparametric estimation of heterogeneity variance for the standardised difference used in meta-analysis

holling(psy.uni-muenster.de SUMMARY The standardised difference has become a frequently used measure of the effect of interest in meta-analysis. Given population heterogeneity, we propose a nonparametric moment estimator for the heterogeneity variance in the corresponding random effects model. The advantages of this approach are threefold. First, it recognises that the specific variances for the individual studies themselves are given in the form of estimates. Secondly, the simple structure of a moment estimator leads to numerical, closed-form expressions. Thirdly, the new estimator appears to behave better than other known estimators. Simulation-free, exact comparisons of the new estimator with the Hedges estimator are provided in terms of bias, variance and mean squared error. Furthermore, by means of a simulation study with unbalanced study sizes we compared the new estimator both with the Hedges estimator and the DerSimonian-Laird estimator.
Design of a passification controller for uncertain fuzzy Hopfield neural networks with time-varying delays

This paper addresses the problem of controller design for passivity of uncertain fuzzy Hopfield neural networks with time-varying delays. The main purpose of this paper is to design a state feedback fuzzy controller such that the resulting closed-loop system is passive. A new set of sufficient conditions are derived for achieving the required result by employing the Lyapunov functional method and matrix analysis technique. The derived criteria are expressed in terms of linear matrix inequalities that can be easily checked using standard numerical software. Two numerical examples with simulation results are given to illustrate the effectiveness and conservatism of the obtained results.
Functional estimation in systems defined by differential equations using Bayesian smoothing methods

Ordinary differential equations (ODEs) are widely used to model physical, chemical and biological processes. Currently, the most commonly used estimation procedures rely on nonlinear least squares. It uses minimization techniques for the estimation of the ODE parameters and a numerical solver for the approximation of the solution. These approaches are computationally intensive and often poorly suited for statistical inference. Recently, a penalized smoothing method was introduced for parameter estimation and approximation of the solution of systems of differential equations. This approach requires an approximation of the state functions involved in the system of differential equations and a penalty term based on all of these equations. It has solved some of the problems encountered in conventional approaches but suffers from two weaknesses: the selection of the ODE-adhesion parameters is not automatic and the uncertainty measures on the estimation of the ODE parameters must be approximated. This thesis proposes to adapt this ODE-penalized smoothing approach in a Bayesian framework for systems of affine differential equations when the data distribution is homogeneous. The two main disadvantages of the frequentist approach are overcome in the Bayesian framework: the selection of the ODE-adhesion parameters is now automatic and the uncertainty measures about parameters can be easily obtained using a sample from the joint posterior distribution. In addition, in this Bayesian approach, prior information about the ODE parameters can be introduced. It manages also in natural way multi-subject studies. Finally, the ODE-adhesion parameters related to each differential equation of the system can be used to validate the proposed dynamic model. The selection of a dynamic model among several alternatives can be obtained by the comparison of the posterior distributions for these ODE-adhesion parameters.
A compressible turbulence model for the pressure–strain correlation

Recent DNS (Direct Numerical Simulation) results indicate that the main compressibility effect comes from the reduced pressure–strain term due to reduced pressure fluctuations. Using the concept of moving equilibrium in compressible homogeneous shear flow, we develop a new compressible pressure–strain model by modifying the incompressible linear pressure–strain model, which is characterized by a decrease in the primary redistribution term but an increase in the secondary redistribution term. The model was applied to a compressible mixing layer. The predicted results show that the growth rate is reduced with increasing convective Mach number and the Reynolds stresses are reduced. All the components of the pressure–strain term and the shear stress anisotropy are reduced with the increase of the compressibility, whereas the normal stress anisotropy is increased—then results are in accord with experimental and DNS results.
Realisation of two adjacent high tones: Acoustic evidence from Northern Sotho

Abstract We present findings of a multi-speaker production study that was undertaken to investigate the realisation of two adjacent high tones within the verb word in Northern Sotho, a Southern Bantu language. Experimental tokens are selected to ensure that the high tones originate from different combinations of morphosyntactic constituents. It is found that the morphosyntactic constituency determines how the adjacent high tones are realised. When both high tones originate within either the inflectional stem or the macrostem constituents, a single pitch peak is realised. Additionally, when the macrostem contains two high tones, the tone of the object concord is absorbed into the stem. Two adjacent high tones, of which one stems from the inflectional stem and the other from the macrostem, produce two pitch peaks, with the latter of the two delayed in order to satisfy the Obligatory Contour Principle. These generalisations are supported by acoustic data. A set of rules is formulated that describes the surface realisation of adjacent high tones in the verbal domain of Northern Sotho (with the exception of one unresolved issue).
Moment method calculation of the propagation constant for leaky-wave modes in slotted rectangular waveguide

A moment method analysis procedure is described to determine the aperture field distribution in a finite-length straight longitudinal slot cut in the broad wall of a rectangular waveguide. The waveguide is fed from one end with the dominant waveguide mode, while the other end of the waveguide is shorted, exactly at the far end of the slot. From the aperture distribution the far-field radiation pattern is then computed, and from the radiation pattern the attenuation and phase constants of the leaky-wave mode in the waveguide are determined. The method of determining the propagation constant from the radiation pattern is an often used experimental technique to determine leaky-wave propagation constants. Computed data is compared to measured data, and good correspondence observed. This propagation constant data can be used to design long meandering leaky-wave slot antennas.
Implementation of a chemo-epitaxy flow for directed self-assembly on 300-mm wafer processing equipment

Abstract. The implementation of our previously reported chemo-epitaxy method for directed self-assembly (DSA) of block copolymers (BCPs) on 300-mm wafers is described in detail. Some challenges to be addressed include edge bead removal control of the layers forming the exposure stack and uniformity of the deposited films across the wafer. With the fine tuning of the process conditions, this flow provides chemically nanopatterned substrates with well-defined geometry and chemistry. After a film of BCP is annealed on the chemical patterns, high degrees of perfection are achieved. A BCP with natural periodicity of 25 nm was assembled on100-nm pitch prepatterns, obtaining 4X feature multiplication. Top-down scanning electron microscope images show a wide process window with depth of focus >200 nm and exposure latitude >40% for lines and spaces of 12.5-nm half-pitch. We provide a platform for future study of the origin of DSA generated defects and their relationship to process conditions and materials that are amenable to use by the semiconductor industry.
Steady‐state event‐excluded proton spectra at solar minimum at all heliolatitudes

We present spectra of a steady foreground population of particles in the inner heliosphere observed by the Heliosphere Instrument for Spectra, Composition, and Anisotopy at Low Energies (HISCALE) on board the Ulysses spacecraft. The observed spectra come from the full range of heliolatitudes visited by Ulysses, −80 to +80 degrees, during Ulysses' first full orbit of the Sun during solar minimum. New corrections for background were applied resulting in a more sensitive and higher energy resolution data set that we used here to analyze quiet‐time (event‐excluded) spectra. We found a persistent foreground population of energetic protons that permeate the inner heliosphere. These protons have complex energy spectra suggesting multiple acceleration sources, and these particles move predominently in non‐radial directions. These findings support the idea that the inner heliosphere acts as a reservoir for energetic protons.
Adaptive pole placement control of a continuous fermentation process

The application of an adaptive pole placement control scheme for the control of real-life biotechnological processes is reported. The problem of simultaneous regulation and tracking of substrate concentration in a continuous fermentation plant is considered in view of recent adaptive control concepts. The process is described by a time-varying non-linear model obtained from mass-balance considerations, where the key process parameter is considered as a time-varying parameter. A discrete-time model is derived. The estimation of this key parameter is carried out using an adaptive filtering scheme. The estimated parameter is used in the explicit design of an adaptive filtering scheme. The estimated parameter is used in the explicit design of an adaptive pole placement algorithm. Good experimental results have been obtained in regulation and tracking, disturbance rejection and transient behaviour, showing the efficiency of this adaptive control scheme.
Adaptive friction compensation with partially known dynamic friction model

This paper illustrates the application of a model-based adaptive friction compensation on a DC motor servomechanism. The dynamic friction model and the control structure studied previously by the authors were used as a basis for this study. The paper first proposes a two-step off-line method to estimate the nominal static and dynamic parameters associated with the model. Then two adaptive globally stable mechanisms are introduced to deal with structured normal forces and temperature variations. Assuming that a nominal friction model is known and that the friction variations can be suitably structured, adaptation is performed on the basis of only one parameter. The paper presents experimental results validating the identification of the dynamic friction model and the adaptive control scheme. These results show that the adaptive loop improves over a fixed compensation scheme and over a PID controller without friction compensation. © 1997 by John Wiley & Sons, Ltd.
A Scale Analysis of Deep Moist Convection and Some Related Numerical Calculations

Abstract A scale analysis valid for deep moist convection is carried out. The approximate equations of motion are anelastic with the time scale set by the Brunt- Vaisala frequency. A new assumption is that the base state potential temperature is a slowly varying function of the vertical coordinate. It is this assumption that eliminates the energetic inconsistency discussed by Wilhelmson and Ogura (1972) for a non-isentropic base state. Another key result is that the dynamic pressure is an order of magnitude smaller than the first-order temperature and potential temperature. In agreement with observations, the kinetic energy is found to be an order of magnitude smaller than the first-order thermodynamic energy. A set of six numerical simulations representing moderately deep moist convection is carried out. The base state is an idealized maritime tropical sounding with no vertical wind shear. The first calculation (Run A) shows the growth and dissipation of a typical shower cloud. The remaining calculations.
Elliptic gaussian random processes

We study the Gaussian random fields indexed by Rd whose covariance is defined in all generality as the parametrix of an elliptic pseudo-differential operator with minimal regularity assumption on the symbol. We construct new wavelet bases adapted to these operators; the decomposition of the field in this corresponding basis yields its iterated logarithm law and its uniform modulus of continuity. We also characterize the local scalings of the fields in terms of the properties of the principal symbol of the pseudodifferential operator. Similar results are obtained for the Multi-Fractional Brownian Motion.
Adaptive filter performance with nonlinearities in the correlation multiplier

It is well known that the correlation multiplier used to form the update signal in adaptive transversal filters need not be a true multiplier. By using an approximate multiplier such as a sign-bit-only multiplier, implementation can be made less costly. In this paper we derive expressions for the convergence rate and misalignment noise of adaptive transversal filters with arbitrary correlation-multiplier non-linearities. The analysis shows any such nonlinearities to always harm performance and quantifies the penalty suffered. Sign-bit-only multiplication suffers a significant penalty, and power-of-two multiplication is suggested as a better alternative. Its performance is almost equal to that of a true multiplier, and in a digital implementation, at least, it is only slightly more difficult to realize than a sign-bit-only multiplier. The theory is developed in a way emphasizing physical understanding and has been verified to be in good agreement with simulation.
Variance function in regression analysis of longitudinal data using the generalized estimating equation approach

Longitudinal or clustered response data arise in many applications such as biostatistics, epidemiology and environmental studies. The repeated responses cannot in general be assumed to be independent. One method of analysing such data is by using the generalized estimating equations (GEE) approach. The current GEE method for estimating regression effects in longitudinal data focuses on the modelling of the working correlation matrix assuming a known variance function. However, correct choice of the correlation structure may not necessarily improve estimation efficiency for the regression parameters if the variance function is misspecified [Wang YG, Lin X. Effects of variance-function misspecification in analysis of longitudinal data. Biometrics. 2005;61:413–421]. In this connection two problems arise: finding a correct variance function and estimating the parameters of the chosen variance function. In this paper, we study the problem of estimating the parameters of the variance function assuming that the form of the variance function is known and then the effect of a misspecified variance function on the estimates of the regression parameters. We propose a GEE approach to estimate the parameters of the variance function. This estimation approach borrows the idea of Davidian and Carroll [Variance function estimation. J Amer Statist Assoc. 1987;82:1079–1091] by solving a nonlinear regression problem where residuals are regarded as the responses and the variance function is regarded as the regression function. A limited simulation study shows that the proposed method performs at least as well as the modified pseudo-likelihood approach developed by Wang and Zhao [A modified pseudolikelihood approach for analysis of longitudinal data. Biometrics. 2007;63:681–689]. Both these methods perform better than the GEE approach.