Miracle-dz/UniFAR-FTUs huggingface dataset:
Electron-based microfocus soft-x-ray source and applications

A compact electron-based microfocus EUV/soft-x-ray source for applications in metrology and microscopy is developed. The source concept is based on the transfer of advanced microfocus x-ray tube technology into the EUV/soft-x-ray spectral range. This allows the realization of a flexible, debris-free, and long-term stable source. Detailed characteristics of the source performance are reported and different applications of the soft-x-ray tube in the field of at-wavelength metrology are presented.
A Minimum Bias Latin Hypercube Design

Deterministic engineering design simulators can be too complex to be amenable to direct optimization. An indirect route involves data collection from the simulator and fitting of less complex surrogates: metamodels, which are more readily optimized. However, common statistical experiment plans are not appropriate for data collection from deterministic simulators due to their poor projection properties. Data collection plans based upon number-theoretic methods are also inappropriate because they tend to require large sample sizes in order to achieve their desirable properties. We develop a new class of data collection plan, the Minimum Bias Latin Hypercube Design (MBLHD), for sampling from deterministic process simulators. The class represents a compromise between empirical model bias reduction and dispersion of the points within the input variable space. We compare the MBLHD class to previously known classes by several model independent measures selected from three general families: discrepancies, maximin distance measures, and minimax distance measures. In each case, the MBLHD class is at least competitive with the other classes; and, in several cases the MBLHD class demonstrates superior performance. We also make a comparison of the empirical squared bias of fitted metamodels. We approximate a mechanistic model for water flow through a borehole, using both kriging and polynomial metamodels. Here again, the performance of the MBLHD class is encouraging.
Electron Radiation Effects on GaAs MESFETs

The effects of low dose electron irradiation on the electrical characteristics of a 0.5 μm commercial low noise GaAs MESPET are evaluated. The dc characteristics, low frequency transconductance, and photoresponse are determined. The radiation induced changes are described and discussed. Die Einflusse einer Elektronenbestrahlung mit niedriger Dosis auf die elektrischen Charakteristiken eines kommerziellen rauscharmen 0,5 μm-GaAs-MESFETs werden berechnet. Die Gleichspannungscharakteristiken, die Niederfrequenzsteilheit und die Photoresponse werden bestimmt. Die strahlungsinduzierten Anderungen werden beschrieben und diskutiert.
Nonlinear dynamical modeling of solar cycles using dynamo formulation with turbulent magnetic helicity

Variations of the sunspot number are important indicators of the solar activity cycles. The sunspot formation is a result of a dynamo process inside the Sun, which is far from being understood. We use simple dynamical models of the dynamo process to simulate the magnetic field evolution and investigate general properties of the sunspot number variations during the solar cycles. We have found that the classical Parker's model in this formulation with a standard kinetic helicity quenching cannot represent the typical profiles of the solar cycle variations of the sunspot number, and also does not give chaotic solutions. For modeling of the solar cycle properties we use a nonlinear dynamo model of Kleeorin and Ruzmaikin (Dynamics of the mean turbulent helicity in magnetic field. Magnetohydrodynamics, 1982, 18, 116–122), which takes into account the dynamics of the turbulent magnetic helicity. We have obtained a series of periodic and chaotic solutions for different layers of the convective zone. The solutions qualitatively reproduce some basic observational features of the solar cycle properties, in particular, the relationship between the growth time and the cycle amplitude. Also, on the longer time scale the dynamo model with the magnetic helicity has intermittent solutions, which may be important for modeling long-term variations of the solar cycles.
Controlled inflation of voids in cellular polymer ferroelectrets: Optimizing electromechanical transducer properties

When exposed to sufficiently high electric fields, polymer-foam electret materials with closed cells exhibit ferroelectric-like behavior and may therefore be called ferroelectrets. In cellular ferroelectrets, the influence of the cell size and shape distributions on the application-relevant properties is not yet understood. Therefore, controlled inflation experiments were carried out on cellular polypropylene films, and the resulting elastical and electromechanical parameters were determined. The elastic modulus in the thickness direction shows a minimum with a corresponding maximum in the electromechanical transducer coefficient. The resonance frequency shifts as a function of the elastic modulus and the relative density of the inflated cellular films. Therefore, the transducer properties of cellular ferroelectrets can be optimized by means of controlled inflation.
Cell-To-Cell Mapping A Method of Global Analysis for Nonlinear Systems

1 Introduction and Overview. - 2 Point Mapping. - 3 Analysis of Impulsive Parametric Excitation Problems by Point Mapping. - 4 Cell State Space and Simple Cell Mapping. - 5 Singularities of Cell Functions. - 6 A Theory of Index for Cell Functions. - 7 Characteristics of Singular Entities of Simple Cell Mappings. - 8 Algorithms for Simple Cell Mappings. - 9 Examples of Global Analysis by Simple Cell Mapping. - 10 Theory of Generalized Cell Mapping. - 11 Algorithms for Analyzing Generalized Cell Mappings. - 12 An Iterative Method, from Large to Small. - 13 Study of Strange Attractors by Generalized Cell Mapping. - 14 Other Topics of Study Using the Cell State Space Concept. - References. - List of Symbols.
LMC clusters - Age calibration and age distribution revisited

The empirical age relation for star clusters in the Large Magellanic Cloud presented by Elson and Fall (1985) are reexamined using ages based only on main-sequence turnoffs. The present sample includes 57 clusters, 24 of which have color-magnitude diagrams published since 1985. The new calibration is very similar to that found previously, and the scatter in the relation corresponds to uncertainties of about a factor of 2 in age. The age distribution derived from the new calibration does not differ significantly from that derived in earlier work. It is compared with age distributions estimated by other authors for different samples of clusters, and the results are discussed. 53 references.
Multiple Testing of Composite Null Hypotheses in Heteroscedastic Models

In large-scale studies, the true effect sizes often range continuously from zero to small to large, and are observed with heteroscedastic errors. In practical situations where the failure to reject small deviations from the null is inconsequential, specifying an indifference region (or forming composite null hypotheses) can greatly reduce the number of unimportant discoveries in multiple testing. The heteroscedasticity issue poses new challenges for multiple testing with composite nulls. In particular, the conventional framework in multiple testing, which involves rescaling or standardization, is likely to distort the scientific question. We propose the concept of a composite null distribution for heteroscedastic models and develop an optimal testing procedure that minimizes the false nondiscovery rate, subject to a constraint on the false discovery rate. The proposed approach is different from conventional methods in that the effect size, statistical significance, and multiplicity issues are addressed integrally. The external information of heteroscedastic errors is incorporated for optimal simultaneous inference. The new features and advantages of our approach are demonstrated using both simulated and real data. The numerical studies demonstrate that our new procedure enjoys superior performance with greater accuracy and better interpretability of results.
On the Decay of Homogeneous Turbulence before the Final Period

A three‐point correlation equation is used to obtain a relation for the triple correlations applicable at times before the final period. In this case the equation is made determinate by neglecting the quadruple correlations. Higher order approximations, valid at still earlier times, could be obtained by considering four‐ or five‐point correlation equations. In each case the set of equations is made determinate by neglecting the highest order correlation. Only two‐ and three‐point correlation equations are considered here. The correlation equations are converted to spectral form by taking their Fourier transforms. Expressions are obtained for the energy transfer function, which describes the transfer of energy from large to small eddies, and for the energy spectrum function which gives the contributions of the various eddy sizes to the total energy. By integrating the energy spectrum over all wave numbers (or eddy sizes), the following energy decay law is obtained: u2¯=A(t−t0)−5/2+B(t−t0)−7, where u2¯ is t.
A simple proof of Rudin's multivariable stability theorem

It is shown how Rudin's multivariable stability theorem can be proved by using simple one-variable arguments, exclusively. In particular, no use is made of multivariable homotopy, in contrast with the original proof. The efficacy of the approach presented here is further illustrated by deriving a new stability test as well as elementary and independent proofs for the classical criteria.
The impact of deep cumulus reflection on the ground-level global irradiance

Abstract The magnitude of solar irradiance reflected from deep cumulus clouds to the ground was evaluated using observations along the Front Range of Colorado. Solar-irradiance reflection around noon was found to cause increases of up to ∼250 W m−2. Enhancements of the global irradiance measured at the surface were observed to persist for 15–30 min. Occasionally, the increased global irradiance prevailed for a period of about 1 h. Model simulations implied similar patterns. It was evaluated that in some locations cloud reflection of solar irradiance may have a seasonal nonrandom pattern, thus increasing its significance. Estimation of the applied impact of cloud-reflected solar irradiance in several relevant situations is provided.
The local structure of finite groups of characteristic 2 type

Part I: Properties of $K$-groups and Preliminary Lemmas: Introduction Decorations of the known simple groups Local subgroups of the known simple groups Balance and signalizers Generational properties of $K$-groups Factorizations Miscellaneous general results and lemmas about $K$-groups Appendix by N. Burgoyne Part II: The Trichotomy Theorem: Odd standard form Signalizer functors and weak proper $2$-generated $p$-cores Almost strongly $p$-embedded maximal $2$-local subgroups References.
Flow Similarity in Compressible Convex-Corner Flows

T HE Prandtl-Meyer expansion is well-known in supersonic convex-corner flows. It is also possible to formulate an interaction law in an explicit form that would relate the displacement effect of the boundary layer to the pressure induced in the inviscid part of subsonicflows. In the literature, studies that attributed theflow properties near the corner to the viscous-invisvid interaction at the transonic flow regime are scarce [1]. For a laminar boundary layer, an analysis by Ruban and Turkyilmaz [2] indicated that the displacement effect near the corner point is primarily due to the inviscid part. The flow is governed by the main part of the boundary layer and the potential flow region outside the boundary layer (inviscid-inviscid interaction). However, a subsequent study by Ruban et al. [3] highlighted the contribution of viscous-inviscid interaction, in which the displacement thickness near the corner is affected by the overlapping region that lies between the viscous sublayer and main part of the boundary layer. For a turbulent boundary layer, Chung [4] indicated that there would be a mild initial expansion, followed by a strong expansion near the corner apex and then downstream recompression for a compressible convex-corner flow. AtM 0:64 and 0.83, the flow is expanded from subsonic to transonic speed when the similarity parameter M 6:14. Note that the convex-corner angle ranges from 5 to 17 deg. A small separation bubble might also be born at the formation of ah normal shock wave [5]. With an increasing convexcorner angle atM 0:83, there is a slight upstreammovement of the separation position and a downstreammovement of the reattachment position. The shock-induced separated region at M 8:95 is expanded and also induces intense surface-pressure fluctuations, which are associated with the intermittent nature of the surface pressure signals or shock-excursion phenomena. The amplitude of peak surface-pressure fluctuations could also be scaledwithM [6]. In Chung’s study [4], it is known that M cannot be used as a similarity parameter for the test cases at M 0:34. However, it is also known that there exists a relationship (i.e., the Prandtl-Glauert rule) [7] between the minimum pressure coefficients for the incompressible airfoil Q2 Cp;ic and compressible airfoil Cp;c, where Cp;c Cp;ic= 1 M p . According to the hypothesis that small streamline deflections produce proportionally small changes in Mach number and pressure, a hodograph solution for compressible flow past a corner was given by Verhoff et al. [8]. The viscous sublayer is relatively unimportant when the Reynolds number is sufficiently large. In terms of the stream function , the hodograph equation for compressible corner flows is given as follows:
Staggered mixed finite volume/finite element method for the Navier-Stokes equations

To solve flow problems associated with the Navier-Stokes equations, we construct a mixed finite volume/finite element method for the spatial approximation of the convective and diffusive parts of the flux, respectively. The finite volume component of the method is adapted from the authors' construction, for hyperbolic conservation laws and rectangular or unstructured triangular grids, of two-dimensional finite volume extensions of the Lax-Friedrichs and Nessyahu-Tadmor central difference schemes, in which the resolution of Riemann problems at cell interfaces is bypassed thanks to the use of the Lax-Friedrichs scheme on two specific staggered grids. MUSCL-type piecewise linear cell interpolants, slope limiters, and a two-step predictor-corrector time discretization lead to an oscillation-free quasi-second-order resolution. For the viscous terms, we use a centered finite element approximation inspired by Rostand-Stoufflet. To improve the quality of the resolution, we use a grid adaptation algorithm proposed by Castro Diaz and Hecht
On Phragmén-Lindelöf’s principle

In the first part of this paper we give a proof of Phragmen-Lindelkf's now classical principlet which is simpler and yields more detailed information than any of the proofs hitherto known. Our procedure consists in proving a theorem in finite terms, similar to Hadamard's three circles theorem, from which the asymptotic statement is shown to follow by a very simple and transparent reasoning. A certain symmetry in the result is obtained by allowing the functions considered to have two possible singularities, one at 0 and one at oo. The ultimate theorem is the sharpest possible and contains all previous results, including those of the brothers Nevanlinna.t In Part II we generalize Phragmen-Lindel6f's principle to harmonic functions of n variables. The methods of Part I are seen to carry over without any difficulties. The result is particularly interesting in so far as the symmetry of the two-dimensional case is not maintained, the extremal functions corresponding to the two singularities being now essentially different.
Optical manipulation of nanoparticles: a review

Optical trapping is an established field for movement of micron-size objects and cells. However, trapping of metal nanoparticles, nanowires, nanorods and molecules has received little attention. Nanoparticles are more challenging to optically trap and they offer ample new phenomena to explore, for example the plasmon resonance. Resonance and size effects have an impact upon trapping forces that causes nanoparticle trapping to differ from micromanipulation of larger micron-sized objects. There are numerous theoretical approaches to calculate optical forces exerted on trapped nanoparticles. Their combination and comparison gives the reader deeper understanding of the physical processes in an optical trap. A close look into the key experiments to date demonstrates the feasibility of trapping and provides a grasp of the enormous possibilities that remain to be explored. When constructing a single-beam optical trap, particular emphasis has to be placed on the choice of imaging for the trapping and confinement of nanoparticles.
Fluid Flow Patterns

A new photographic technique is described, for observing velocity fields in water, induced by the entry of solid missiles. The results of a number of observations are given, and compared with theoretical formulas. The corrections involved in the method are analyzed theoretically, and the theory of the corrections confirmed experimentally. It appears that the method is well adapted to velocity fields 5–100 feet per second, created by objects several inches or more in diameter, but may lead to troublesome corrections at other speeds or with smaller objects.
An index to measure the ability of first year science students to transfer mathematics

This project aimed to quantitatively measure the ability of first year science students to transfer their mathematical skills and knowledge to a physical context. An instrument used in earlier studies to measure transfer of mathematical knowledge was modified for this project, and tested with 49 student volunteers. This paper presents the Transfer Index, a novel way of measuring the degree of transfer of the students' mathematics skills and knowledge. It is demonstrated that the Transfer Index is a useful way of quantifying transfer and that it has predictive validity in a natural educational setting.
Variation of the vertical directionality of noise with depth in the North Pacific

A vertical array of 20 vibration isolated hydrophones was suspended from the Research Platform FLIP at various depths from 713 to 4816 m. Preformed sets of beams were formed with a digital beamformer to observe the vertical noise distribution at several frequencies between 23 and 100 Hz. Directional spectra derived from 10‐min samples of digital records are presented. Interpretation of the data set leads to a model for the vertical noise directional spectrum as a function of depth which indicates a reduction of a factor of 2 in the vertical extent of the noise window as depth increases from the sound channel axis to the critical depth. This reduction in width is accompanied by a reduction in the maximum level of about 4 dB. The effect is essentially independent of frequency over the observed range of 23 to 100 Hz. No horizontal null in the directional spectrum of the noise, as predicted by ray theory for a horizontally homogeneous ocean, was observed in the data.
The energy dependence of the positronium formation cross section in helium

The total cross section for positronium formation in helium for positrons of energies E from threshold (17.8 eV) to 250 eV has been measured using a gas cell transmission method. The results indicate that the cross section above E=60 eV is satisfactorily described by 0.5e-0.02E pi a02, tending to zero at energies close to 200 eV. The approximate description of the cross section at intermediate energies, falling as E-2.5, is consistent with a number of theoretical predictions but is in conflict with earlier experiments, which show an E-1 behaviour. The implications of these measurements are discussed, with particular reference to the observed merging of the total cross sections for positron- and electron-helium scattering at intermediate energies.
Effect of parasitic element on the characteristics of microstrip antenna

The variations in the sizes and position of a parasitic element with the input impedance and bandwidth of a rectangular microstrip antenna are investigated by the method of moments. An integral equation for the unknown patch current densities is formulated in the spectral domain. The Galerkin procedure is employed to solve for the unknowns. It is found that the input impedance varies significantly with the size and position of the parasitic patch. The result is important for bandwidth enhancement and impedance matching of the microstrip antenna. >
Young Stellar Objects science with interferometry

The study of Young Stellar Objects (YSOs) is one of the most exciting topics to be handled by long baseline optical interferometry. The magnitudes of these stars are at the edge of capabilities of current optical interferometers limiting the studies to a few of those but are well within the capability of coming large aperture interferometers like the VLT Interferometer, the Keck Interferometer, the Large Binocular Telescope or 'OHANA. The milli-arcsecond spatial resolution reached by interferometry allows to probe the very close environment of young stars down to a tenth of an astronomical unit. In this paper, I review the different aspects of star formation that can be tackled by interferometry: circumstellar disks, multiplicity, jets, etc. I present recent observations performed with operational infrared interferometers, IOTA, PTI and ISI, and I show why in the next future we will extend these studies with large aperture interferometers.
The study on mechanical response of human histiocytic lymphoma cells using an atomic force microscope

Abstract This work measures force curves of human histiocytic lymphoma cells under a liquid phase using the atomic force microscope (AFM). The experiment uses thirty of the same type and different size cells throughout the experiment. This study analyzes force curves of the cells and calculates the Young's modulus by analyzing the recorded force curves with the help of the Hertz model. The experiment also destroys the cells under continuously applied loading force using an AFM tip. Results show a flat force curve following point of contact for both intact cell and apoptosis cell (entirely destroyed). The force curve of the apoptosis cell becomes steeper than that of the intact cell with increasing loading forces. The calculated Young's modulus of the intact cell nucleus is dependent on the applied loading force of the AFM tip. The Young's modulus of the apoptosis cell also increases over one order of magnitude from that of the intact cell. The average force curve slope for an intact cell in the present experimental data of thirty cells is ‐7.4 ± 1.8 nN/μm, ‐20.0 ± 4.7 nN/μm for the dying cell, and ‐349.5 ± 25.8 nN/μm for the apoptosis cell.
Gevrey regularity of solutions to the 3-D Navier-Stokes equations with weighted $l_p$ initial data

We prove the existence and Gevrey regularity of local solutions of the three dimensional periodic Navier-Stokes equations in case the sequence of Fourier coefficients of the initial data lies in an appropriate weighted lp space. Our work is motivated by that of Foias and Temam ([10]) and we obtain a generalization of their result. In particular, our analysis allows for initial data that are less smooth than in [10] and can also have infinite energy. Our main tool is a variant of the Young convolution inequality enabling us to estimate the nonlinear term in weighted lp norm.