Miracle-dz/UniFAR-FTUs huggingface dataset:
Bell-Plesset effects for an accelerating interface with contiguous density gradients

A Plesset-type treatment [M. S. Plesset, J. Appl. Phys. 25, 96 (1954)] is used to assess the effects of contiguous density gradients at an accelerating spherical classical interface on Rayleigh-Taylor and Bell-Plesset perturbation growth. Analytic expressions are obtained that describe enhanced Rayleigh-Taylor instability growth from contiguous density gradients aligned with the acceleration and which increase the effective Atwood number of the perturbed interface. A new pathway for geometric amplification of surface perturbations on an accelerating interface with contiguous density gradients is identified. A resonance condition between the density-gradient scale length and the radius of the interface is also predicted based on a linearized analysis of Bernoulli’s equation, potentially leading to enhanced perturbation growth. Comparison of the analytic treatment with detailed two-dimensional single-mode growth-factor simulations shows good agreement for low-mode numbers where the effects of spherical geom.
An Integral Computational Model for Crack Simulation and Detection via Eddy Currents

In this paper an innovative technique is described to solve the electromagnetic problem in the presence of a cracked conductor. Both the direct problem (given the crack, compute the scattered field) and the inverse problem (given the external measurements, obtain the crack position and shape) are dealt with. The features of an integral formulation in terms of a two-component electric vector potential expanded over edge elements are fully exploited. The resulting method proves to be extremely efficient, also thanks to the binary nature of the unknown. In this paper we restrict our attention to a class of problems, namely the eddy current testing for thin cracks in non-magnetic metallic plates, but the method can be extended to more general cases.
Stabilität und Konvergenz von Mehrschrittverfahren zur numerischen Lösung quasilinearer Anfangswertprobleme

In der vorliegenden Arbeit wird eine hinreichende Bedingung fur die Konvergenz expliziter Mehrschrittverfahren zur numerischen Losung von Anfangswertaufgaben gewisser quasilinearer partieller Differentialgleichungen angegeben. Die Darstellung schliest sich weitgehend an die von P. D. Lax und R. D. Richtmyer im Jahre 1956 in [8] fur lineare entwickelte und von R. Ansorge im Jahre 1967 in [1] auf halblineare erweiterte und im Jahre 1969 in [2] fur quasilineare Probleme formulierte Theorie an. In this paper a sufficient criterion is given for the convergence of explicit multistep methods for initial-value problems of certain quasilinear partial differential equations. We use the general approach developed by P. D. Lax and R. D. Richtmyer in 1956 (c.f.[8]) for linear problems and extended by R. Ansorge in 1967 (c.f.[1]) to semilinear and in 1969 (c.f.[2]) in part to quasilinear problems.
A Theorem on k-Saturated Graphs

In this paper we consider finite graphs without loops and multiple edges. A graph is considered to be an ordered pair 〈G, *〉 where G is a finite set the elements of which are called the vertices of while * is a subset of [G]2 (where [G]2 is the set of all subsets of two elements of G). The elements of * are called the edges of . If {P, Q} ∊ *, we say that Q is adjacent to P. The degree of a vertex is the number of vertices adjacent to it. Let k be an integer. We say that is the complete k-graph if G has k elements and * = [G]2.
Electrical behavior of zinc oxide layers grown by low temperature atomic layer deposition

We report on the electrical properties of thin film transistors based on zinc oxide (ZnO) layers grown by low temperature (100–170°C) atomic layer deposition. As evidenced through Hall effect measurements, a drastic decrease of the carrier concentration occurred for ZnO films grown at 100°C. Time of flight–secondary ions mass spectroscopy analysis revealed that this decrease is associated with an increase of the hydroxide groups in the ZnO layer which suppressed oxygen vacancy formation. Transistors fabricated from ZnO films grown at 100°C exhibit a high Ion∕Ioff ratio (∼107) and an encouraging intrinsic channel mobility (∼1cm2∕Vs).
Antiferromagnetic order of effective Zn moments in La2-xSrxCuO4 (x≤0.03)

We have measured the static magnetic susceptibility of La 2 - x Sr x Cu 1 - x Zn 2 O 4 in order to study the magnetic contribution of Zn doping induced spin vacancies in the CuO 2 planes. Our data clearly show that these effective Zn moments (EZM) are antiferromagnetically ordered below the Neel temperature T N of the Cu spin lattice. Above T N the EZM behave like a Curie-Weiss paramagnet with a small effective moment of μ e f f ∼0. 65μ B /Zn atom, which indicates that strong antiferromagnetic correlations between the EZM persist for T>T N . Furthermore, we have analyzed the height of the Neel peaks, to determine the susceptibility Χ(EZM) of the EZM for T>T N directly from the experimental data. We find that in the paramagnetic phase the temperature dependence of Χ(EZM) is different from that in the antiferromagnetic phase. To describe Χ(EZM) for T<T N one has to take the order parameter of the Cu spins into account. As a consequence it is impossible to describe Χ(EZM) in the entire temperature range with the same Curie-Weiss law.
Leader filament study near the anode in a rod plane gap

Experimental results concerning the behaviour of leader filaments near the anode are obtained using schlieren techniques in the case of small and large air gaps. Two main phases are studied. The first one, associated with injection of current (active phase), exhibits a perturbation of thermal and electrical properties of the leader near the anode. The study of the second phase, corresponding to a zero current injection (relaxation phase), allows the measurement of the recovery time of air density inside the leader channel.
Flux-Corrected Transport

This paper describes a class of explicit, Eulerian finite-difference algorithms for solving the continuity equation which are built around a technique called “flux correction. ” These flux-corrected transport (FCT) algorithms are of indeterminate order but yield realistic, accurate results. In addition to the mass-conserving property of most conventional algorithms, the FCT algorithms strictly maintain the positivity of actual mass densities so steep gradients and inviscid shocks are handled particularly well. This first paper concentrates on a simple one-dimensional version of FCT utilizing SHASTA, a new transport algorithm for the continuity equation, which is described in detail.
Very fast FEM Poisson solvers on lower precision accelerator hardware

Recently, accelerator hardware in the form of graphics cards including Tensor Cores, specialized for AI, has significantly gained in importance in the domain of high performance computing. For example, NVIDIA’s Tesla V100 promises a computing power of up to 125 TFLOP/s achieved by Tensor Cores, but only if half precision floating point format is used and arithmetically intensive operations including dense matrices are performed. When trying to use such lower precision hardware for numerical simulations, i.e., solving partial differential equations with a matrix-based finite element method and a standard multigrid solver, it becomes clear that the peak rates are not nearly reached, not to mention possible problems regarding accuracy. However, if low condition numbers and many dense matrix operations are involved, the indicated high performance can be reached while preserving sufficient accuracy.
Energy-storage performance and electrocaloric effect in (100)-oriented Pb0.97La0.02(Zr0.95Ti0.05)O3 antiferroelectric thick films

(100)-oriented Pb0.97La0. 02(Zr0.95Ti0.05)O3 (PLZT) antiferroelectric films with a thickness of about 1.7 μm were deposited on Pt-buffered silicon substrates via a sol-gel process. The room-temperature capacitance density of the films was above 195 nF/cm2 over the frequency range from 1 kHz to 1 MHz. The recoverable energy density was enlarged with increasing measurement field, and a maximum value of 12.4 J/cm3 at 1120 kV/cm was obtained at room temperature. From the temperature-dependent electric-field-induced polarization hysteresis loops, a maximum reversible adiabatic temperature change, ΔT = 8.5 °C, was obtained near the phase-transition temperature.
Working Characteristics of a Mechanical Insufflation-Exsufflation Device

Secretions of ventilated patients must be cleared efficiently and timely; to improve the secretion clearance efficiency of an insufflation-exsufflation device (IL-IE device) and lay a foundation for the optimization of the IL-IE device, a mathematical model of the ventilation system with the IL-IE device is set up. Through the experimental and simulation research on the ventilation system, it can be concluded that, firstly, the mathematical model is proved to be authentic and reliable. Secondly, with the deposition of secretion or an increase in the respiratory compliance, the peak exsufflation airflow may be reduced. Thirdly, with a decrease in the suction pressure, the peak exsufflation airflow of the ventilated lung may rise proportionally, but the minimum pressure in the ventilated lung may descend proportionally. To improve the efficiency of the secretion clearance but not to injure the ventilated patient, the suction pressure can be elevated properly. Last, increasing the inspiratory positive airway pressure (IPAP) is a method to improve the secretion clearance efficiency. This research lays a foundation for improving the secretion clearance efficiency of the IL-IE device.
Twin Bearingless Machine Drive Configurations With a Reduced Number of Inverters

Bearingless motors combine torque and magnetic levitation into a single electric machine. Recent research indicates that this technology has the potential to yield a reliable, oil-free, highly-efficient, and integrated solution for industrial applications if the cost associated with the electric drive can be reduced. This paper investigates power electronic implementations that reduce the required number of inverters, and thereby reducing the drive cost. The paper targets electric machinery for significant power applications, such as compressor systems, which require active actuation in all degrees of freedom (DOF). The paper shows that by implementing the system as a twin bearingless machine configuration, with each machine using a combined winding, the number of inverters (and supporting components) can be reduced by 25% through novel connections of the winding coil groups. Nine reduced-component twin bearingless machine drive configurations are proposed, evaluated, and compared. Power electronic and control implementations are proposed and experimental results demonstrate reduced-component drives levitating a prototype twin machine and controlling machine coil currents identically to the conventional (full-cost) bearingless drive.
A Study of Bending Effect on Pulse-Frequency-Modulation-Based Photosensor for Retinal Prosthesis

In this work, we study the effect of bending on the pulse-frequency-modulation (PFM)-based photosensor. Based on the results of our study of strain on metal oxide semiconductor field-effect transistor (MOSFET) devices, we explain the behavior of the photosensor under compressive and tensile bending. We found that the maximum frequency variation to bending is about +4% when extrapolated to the curvature of the human eye. From this study we hope to minimize or eliminate the effect of bending on LSI circuits. Although this study specifically deals with the PFM photosensor circuit, any other LSI circuit subjected to strain can be treated similarly.
The X-ray surface brightness profiles of hot galaxy clusters up to $\vec z$ ~ 0.8: Evidence for self-similarity and constraints on $\Omega_\mathsf{0}$

We study the surface brightness profiles of a sample of 25 distant $(0.3 3.5~\rm keV)$ clusters, observed with ROSAT, with published temperatures from ASCA. For both open and flat cosmological models, the derived emission measure profiles are scaled according to the self-similar model of cluster formation. We use the standard scaling relations of cluster properties with redshift and temperature, with the empirical slope of the relation derived by Neumann & Arnaud ([CITE]). Using a $\chi^2$ test, we perform a quantitative comparison of the scaled emission measure profiles of distant clusters with a local reference profile derived from the sample of 15 hot nearby clusters compiled by Neumann & Arnaud (1999), which were found to obey self-similarity. This comparison allows us to both check the validity of the self-similar model across the redshift range $0.04{-}0.8$, and to constrain the cosmological parameters. For a low-density flat universe, the scaled distant cluster data were found to be consistent, both in shape and normalisation, with the local reference profile. It indicates that hot clusters constitute a homologous family up to high redshifts, and gives support to the standard picture of structure formation for the dark matter component. Because of the intrinsic regularity in the hot cluster population, the scaled profiles can be used as distance indicators, the correct cosmology being the one for which the various profiles at different redshifts coincide. The intrinsic limitations of the method, in particular possible systematic errors and biases related to the model uncertainties, are discussed. Using the standard evolution model, the present data allow us to put a tight constraint on $\Omega_{0}$ for a flat Universe: $\Omega_{0}=0.40^{+0.15}_{-0.12}$ at 90% confidence level (statistical errors only). The critical model ($\Omega_{0}=1$) was excluded at the 98% confidence level. Consistently, the observed evolution of the normalisation of the relation was found to comply with the self-similar model for $\Omega_{0}=0.4$, $\Lambda=0.6$. The constraint derived on $\Omega_{0}$ is in remarkable agreement with the constraint obtained from luminosity distances to SNI or from combined analysis of the power spectrum of the 2dF galaxy redshift Survey and the Cosmic Microwave Background anisotropies.
The nature of the optical filaments in Centaurus A. Evidence for a beamed ionizing continuum

New observations, including both narrow-band imaging and long-slit spectroscopy, of the optical filaments in Centaurus A are presented. The line-emitting filaments which compose part of the well-known optical-jet are complex and highly structured at the limit of ground-based resolution. Variations in the surface brightness, line intensity ratios and the velocity field occur on spatial scales ∼ 100 pc. No evidence of [O III] λ5007 emission associated with either the inner jet or a possible counter jet are found. The emission line spectra of the filaments are very similar in character to those of the spatially extended nebulosities in more distant radio galaxies and radio quasars.
The elements of aerofoil and airscrew theory

1. Introduction 2. Bernoulli's equation 3. The stream function 4. Circulation and vorticity 5. The velocity potential and the potential function 6. The transformation of a circle into an aerofoil 7. The aerofoil in two dimensions 8. Viscosity and drag 9. The basis of aerofoil theory 10. The aerofoil in three dimensions 11. The monoplane aerofoil 12. The flow round an acerofoil 13. Biplane aerofoils 14. Wind tunnel interference on areofoils 15. The airscrew: momentum theory 16. The airscrew: blade element theory 17. The airscrew: wind tunnel interference Appendix Bibliography Index.
The JCNS neutron spin-echo spectrometer J-NSE at the FRM II

Neutron spin echo (NSE) spectroscopy is, due to its high energy resolution, a well-suited method for studying slow dynamics, such as the dynamics of soft matter systems (glasses, polymers and complex liquids), or paramagnetic properties of, e.g., spin glasses. The Jülich NSE spectrometer has been in operation at the Jülich research reactor FRJ-2 since 1996. It has been transferred now to the new research reactor FRM II of the TU München, where it just started to continue operation. In the context of the transfer, parts of the spectrometer have been renewed and improved, leading to a significantly larger energy resolution and a larger dynamic range. Amongst other things, new correction coils have been designed and manufactured, allowing us to use higher currents in the main precession coils. The neutron guide system of the J-NSE allows the variation of the wavelength between about 4.5 to 16 Å. A larger neutron guide exit of 60 × 60 mm2, the higher neutron flux, the possibility of varying the wavelength over a broad range and the better correction elements push the performance of the instrument to Fourier times τ = 1 ps to about 350 ns, with a q-range of q = 0.02–1.5 Å−1. We describe here the technical changes and improvements of the J-NSE and show the first spin echoes measured with the reinstalled spectrometer.
Weak approximations for quantile processes of stationary sequences

ABSTRACT By studying the deviations between uniform empirical and quantile processes (the so-called Bahadur-Kiefer representations) of a stationary sequence in properly weighted sup-norm metrics, we find a general approach to obtaining weighted results for uniform quantile processes of stationary sequences. Consequently we are able to obtain weak convergence for weighted uniform quantile processes of stationary mixing and associated sequences. Further, by studying the sup-norm distance of a general quantile process from its corresponding uniform quantile process, we find that information at the two end points of the uniform quantile process can be so utilized that this weighted sup-norm distance converges in probability to zero under the so-called Csorgo-Revesz conditions. This enables us to obtain weak convergence for weighted general quantile processes of stationary mixing and associated sequences. L'etude des deviations entre les processus uniformes empiriques et les processus quantiles, les denommees representations Bahadur-Kiefer, d'une sequence stationnaires en sup-metriques adequatement ponderees, nous revele une approche generale pour obtenir des resultats ponderes pour les processus uniformes quantiles de sequences stationnaires. Nous pouvons, en consequence, obtenir une convergence faible pour les processus uniformes quantiles ponderes de sequence stationnaires de melange et de sequences associees. De plus, I'etude de la distance induite par la supnorme entre un processus quantile general et ses processus uniformes quantiles correspondants nous revele que I'information aux deux exertmites du processus uniforme quantile peut ětre utilisee de telle maniere que cette distance induite par la sup-norme et ponderee converge a zero en probabilite sous les conditions denommees Csorgo-Reesz. Ceci nous permet d'obtenir des convergences faibles pour les processus quantiles generaux ponderes de sequence stationnaires de melange et de sequences associees.
Randomization Based Tests

I argue that when an experiment in behavioral psychology is designed, it almost always involves taking a nonrandom sample and, by a process of randomization, dividing it into two or more ‘treatment’ groups. This places such experiments within the randomization model of inference, not the better-known population model. The appropriate tests of significance under the randomization model are permutation (randomization) tests. Keywords: Bayesian model; exact tests; Fisher; permutation tests; population model; randomization model
An accelerated deflation preconditioner for parametric systems based on subspace recycling

Krylov subspace recycling [1] is often deployed to accelerate the iterative solution of sequences of linear systems. Such approaches reuse a continuously updated deflation subspace to reach a converged solution within a low number of iterations. This procedure is justified for problems that describe gradually evolving phenomena, such as crack propagation, and thus involve a sequence of systems that are not simultaneously available. However considering parametric systems, these techniques might induce an unnecessary overhead cost. Specifically, by constantly updating the recycled subspace a new projection on the newly constructed subspace needs to be operated for each new system, inducing a cost that scales with O(l×N) for dense systems, where N is the size of the system and l is the size of the employed recycled basis.
The muon (g-2) Standard-Model prediction and GeV-scale new physics

The discrepancy between the standard model (SM) prediction for the muon anomalous magnetic moment and the experimental result is accompanied by other anomalies. A crucial input for the prediction is the hadronic vacuum polarization inferred from hadronic data. However, the two most accurate determinations from KLOE and BaBar disagree by almost 3 𝜎 . Additionally, the combined data-driven result also disagrees with the most precise lattice determinations in the intermediate energy window at the level of ∼ 4 . 2 𝜎 . We show with a simple model that all these discrepancies could be accounted for by a new boson produced resonantly around the KLOE centre-of-mass energy and decaying promptly yielding lepton pairs and missing energy in the final states, while complying with all phenomenological constraints.
FUZZY LOGIC, FUZZY SETS, AND NATURAL LANGUAGES

This is an overview paper presenting the main results obtained by the author and his colleagues in the field of fuzzy logic and modelling of natural language semantics and is composed of an introduction followed by two main parts. Section 2 discusses our results in terms of fuzzy logic, namely that of prepositional and first-order fuzzy logic based on a residuated lattice of truth values. Section 3 presents the concept of the Alternative mathematical Model of natural Language semantics and pragmatics (AML) the development of which is based on a philosophical approach rather than the approaches usually adopted in most classical papers.
Delay‐dependent LMI condition for global asymptotic stability of discrete‐time uncertain state‐delayed systems using quantization/overflow nonlinearities

A delay‐dependent criterion for the global asymptotic stability of a class of uncertain discrete‐time state‐delayed systems using various combinations of quantization and overflow nonlinearities is presented. The proposed criterion is in the form of a linear matrix inequality and, hence, computationally tractable. A numerical example highlighting the usefulness of the proposed criterion is given. Copyright © 2010 John Wiley & Sons, Ltd.
An invariant‐preserving approach to robust finite‐element multibody simulation

We briefly describe the main concepts that have inspired a novel approach for the integration of general non‐linear structural and multibody dynamics problems within a finite‐element framework that includes geometrically exact beams. In this approach, a numerically robust family of second to fourth order accurate algorithms are devised, which retain several important qualitative features of the exact solution. Among these, we address frame indifference, invariance with respect to reference entities (such as beam axes and shell mid‐surfaces), and, for load‐free motions, preservation of the system total linear and fixed‐pole angular momenta and a rigorous bound on the system total mechanical energy. When constrained systems are analyzed, these results are obtained by additionally requiring at the discrete level the preservation of Newton's Third Law of Action and Reaction and the vanishing of the work of the reaction forces for each constrained body pair. As a result, the schemes exhibit full non‐linear unconditional stability according to the Energy Method. The underlying single‐step, two‐stage, implicit difference schemes provide tunable high‐frequency damping ranging from null (ρ∞ = 1) to asymptotic annihilation (ρ∞ = 0). Representative numerical exercises are included to illustrate the main features of the methodology.