Miracle-dz/UniFAR-FTUs huggingface dataset:
Interference of autoionising transitions in fast ion-atom collisions

The authors show that the influence of post-collision interaction (PCI) on the energy spectra of autoionisation electrons cannot be neglected in ion-atom collisions, even at collision energies as high as several hundred keV and with light projectiles. By means of a classical treatment they derive simple formulae that allow PCI effects to be properly taken into account at high collision energies. From electron energy spectra calculated with these formulae it becomes obvious that interferences of autoionising transitions can significantly influence the apparent peak intensities, even if these peaks seem to be well separated and no typical interference structures can be observed. The authors reanalyse the experimental data of Itoh et al. (1985) who investigated the electron spectra from high-energy He++He collisions and found peculiarities in the collision energy dependence of the observed electron intensities.
Scaling high-power ultrafast VECSELs into the femtosecond regime

The combination of high output power and femtosecond pulses from VECSELs and MIXSELs would be very attractive for many applications. To explore the limitations, a quantitative understanding of the pulse formation processes is required. Our numerical simulations showed a good qualitative agreement with experimental results in the picosecond regime. By minimizing intracavity group delay dispersion (GDD) and improving gain bandwidth and SESAM parameters, our model predicts pulses as short as 250 fs. As a first step we minimized GDD with a top coating which provides values between ±10 fs2 over a range of 30 nm around the design wavelength.
Comparison of approximated solutions for the phase velocity of Rayleigh waves (Comment on ‘Characterization of surface damage via surface acoustic waves’)

An approximation for the SAW velocity (Rayleigh waves) in dependence on Poisson’s ratio, which was misprinted in a former paper (P D Warren et al 1996 Nanotechnology 7 295–301), is corrected. At the same time, the connection of this approximation with the recent history of exact formulae for the Rayleigh-wave velocity is established.
Building Editable Free-form Models from Unstructured Point Clouds

AbstractWe present a novel approach to reconstructing the surface of a 3D object using a point cloud of its surface scan. The objective is to obtain an editable CAD model that is manufacturable and describes accurately the structure and topology of the point cloud. The point cloud is sliced into cross sections. Each cross section is represented as a 2D point set. Then, a collection of interpolating curves is computed that describes each cross section accurately, using computational geometry methods on the corresponding point set. The organized point set for the surface reconstruction is obtained from these curves. Freeform transformations may also be applied, allowing high level global editing of the final object.
Random linking of lattice polygons

We study the linking probability of polygons on the simple cubic lattice. In particular, we consider two polygons each having n edges, confined to a cube of side L, and ask for the linking probability as a function of n and L. We also consider other situations in which the polygons are restricted to be not too far apart, but not necessarily confined to a cube. We prove several rigorous results, and use Monte Carlo methods to address some questions which we are unable to answer rigorously. An interesting feature is that the linking probability is a function of L/nv, where v is the exponent characterizing the radius of gyration of a polygon.
Absolute in situ measurement of surface dangling bonds during a-Si:H growth

Hydrogenated amorphous silicon (a-Si:H) is regarded as a model system in mechanistic studies of amorphous semiconductor film growth, where the key reactive site is generally considered to be a surface “dangling bond. ” Employing an ultrahigh-Q (≈1010) monolithic optical resonator, the authors probe the creation of dangling-bond defects during growth of a-Si:H from a predominantly SiHx (x=0–3) radical flux by detecting the associated near-IR subgap absorption with evanescent wave cavity ringdown spectroscopy. They find the apparent dangling-bond creation rate [(5±3)×1012cm−2s−1] and steady-state surface density [(5±2)×1011cm−2] to be considerably lower than expected from dangling-bond-based growth mechanisms.
Search for second overtone mode Cepheids in Magellanic Clouds - II. Characteristics of second overtone mode pulsations

The analysis of CCD observations of ten new suspected second overtone mode Cepheids in the SMC does not confirm the nature of such stars; most of them appear to be first overtone mode Cepheids. A careful analysis of the OGLE best second overtone mode candidates and of the second overtone component of double mode Cepheids in SMC and LMC has been performed in order to clarify the possible effects of a resonance between pulsation modes. There are some indications that such a resonance is indeed operating in these pulsators. A brief discussion of the effects of blending on the light curve shape is also reported, and the usefulness of the Fourier parameters as mode discriminators is discussed.
Neural-network-assisted genetic algorithm applied to silicon clusters

Recently, a new optimization procedure that combines the power of artificial neural-networks with the versatility of the genetic algorithm (GA) was introduced. This method, called neural-network-assisted genetic algorithm (NAGA), uses a neural network to restrict the search space and it is expected to speed up the solution of global optimization problems if some previous information is available. In this paper, we have tested NAGA to determine the ground-state geometry of Si{sub n} (10{<=}n{<=}15) according to a tight-binding total-energy method. Our results indicate that NAGA was able to find the desired global minimum of the potential energy for all the test cases and it was at least ten times faster than pure genetic algorithm.
Micron-Size Optical Waveguide for Optoelectronic Integrated Circuit

Fundamental technologies for the optical interconnection in the VLSI chip have been developed by using conventional Si LSI technologies. The micron-size optical waveguide consisting of Si3N4 core and SiO2 cladding layers has been fabricated by low-pressure chemical vapor deposition (LPCVD) and atmospheric-pressure chemical vapor deposition (APCVD), respectively. The small lenses and the micron-size mirror which changes the light propagation direction from vertical to horizontal for the interlayer interconnection have also been fabricated.
Towards more replicable content analysis for learning analytics

Content analysis (CA) is a method frequently used in the learning sciences and so increasingly applied in learning analytics (LA). Despite this ubiquity, CA is a subtle method, with many complexities and decision points affecting the outcomes it generates. Although appearing to be a neutral quantitative approach, coding CA constructs requires an attention to decision making and context that aligns it with a more subjective, qualitative interpretation of data. Despite these challenges, we increasingly see the labels in CA-derived datasets used as training sets for machine learning (ML) methods in LA. However, the scarcity of widely shareable datasets means research groups usually work independently to generate labelled data, with few attempts made to compare practice and results across groups. A risk is emerging that different groups are coding constructs in different ways, leading to results that will not prove replicable. We report on two replication studies using a previously reported construct. A failure to achieve high inter-rater reliability suggests that coding of this scheme is not currently replicable across different research groups. We point to potential dangers in this result for those who would use ML to automate the detection of various educationally relevant constructs in LA.
Optimization of stochastic linear systems with additive measurement and process noise using exponential performance criteria

The expected value of a multiplicative performance criterion, represented by the exponential of a quadratic function of the state and control variables, is minimized subject to a discrete stochastic linear system with additive Gaussian measurement and process noise. This cost function, which is a generalization of the mean quadratic cost criterion, allows a degree of shaping of the probability density function of the quadratic cost criterion. In general, the control law depends upon a gain matrix which operates linearly on the smoothed history of the state vector from the initial to the current time. This gain matrix explicitly includes the covariance of the estimation errors of the entire state history. The separation theorem holds although the certainty equivalence principle does not. Two special cases are of importance. The first occurs when only the terminal state is costed. A feedback control law, linear in the current estimate of the state, results where the feedback gains are functionally dependent upon the error covariance of the current state estimate. The second occurs if all the intermediate states are costed but there is no process noise except for an initial condition uncertainty. A feedback law results which depends not only upon the current dynamical state estimate but also on an additional vector which is path dependent.
Incomplete covariates in the Cox model with applications to biological marker data

A common occurrence in clinical trials with a survival end point is missing covariate data. With ignorably missing covariate data, Lipsitz and Ibrahim proposed a set of estimating equations to estimate the parameters of Cox's proportional hazards model. They proposed to obtain parameter estimates via a Monte Carlo EM algorithm. We extend those results to non‐ignorably missing covariate data. We present a clinical trials example with three partially observed laboratory markers which are used as covariates to predict survival.
On (national) citizenship and (de)politicised nations: Everyday discourses about the Catalan secessionist movement

This paper examines the Catalan independentist movement understood as a paradigmatic case of secessionist politics in a European context. Drawing on recent rhetorical-psychological studies on citizenship and nationhood, we explore how constructions of citizenship and national identity interweave to shape, warrant, and contest opposing arguments about Catalan independence and Spanish sovereignty. We conducted a discursive-rhetorical analysis of thirty open-ended interviews and one focus group with Catalan residents that held different positions towards independence. The analysis shows that arguments for independence construct secession demands as a citizenship right that, in turn, assumes different versions of the Catalan national community. Arguments against independence reify the Spanish national identity by constructing it as a political community where all citizens have the same rights. Both argumentative poles position “the nation” as a core element in political citizenship discourses. Specifically, we argue that a diversity of citizenship formulations stressing democratic rights, practices, and political traditions, rhetorically work both to support and to challenge otherwise explicitly ethnic, cultural, and civic understandings of nationhood. The article advances a historically situated approach of citizenship and national categories attending to their specific rhetorical mobilisations in current independentist conflicts.
Waves and turbulence in high Mach number nearly parallel collisionless shocks

We have performed a number of one-dimensional hybrid simulations (massless electrons, macroions) of almost parallel collisionless shocks (angle between the upstream magnetic field and shock normal of 5°) for medium and high Mach number shocks. One of the key questions we address is whether downstream convected upstream waves or waves locally generated at the interface of the incoming solar wind and the partially thermalized plasma are the main source of the downstream turbulence. In the medium, supercritical Mach number regime the small-wavelength interface waves are damped in a transition region and contribute to downstream dissipation [Krauss-Varban, 1995]. These waves are right-hand polarized and propagate in the downstream rest frame toward the shock. In an Alfven Mach number regime around MA ∼ 8 we find behind the shock ramp right-hand polarized waves with both helicities. These are interpreted in terms of both the ion/ion resonant and the ion/ion right-hand nonresonant instability occurring in the shock transition region. The latter occurs, according to linear theory, when the beam density is high and when the relative speed between the ion beam and the ambient ions is large. In this Mach number regime the shock-produced waves have larger wavelengths and are less strongly damped. We suggest that they are subject to a parametric decay instability, resulting in an inverse cascade of short-wavelength waves to longer ones farther downstream. In the very high Mach number regime, damping as well as decay of the shock-produced waves is slow in comparison with the transit time from the shock to the magnetopause. The shock-generated waves are then the dominant source of the downstream turbulence.
A practical, general‐purpose, two‐state HLL Riemann solver for hyperbolic conservation laws

In this paper, we construct a general‐purpose Riemann solver for hyperbolic conservation laws that does not involve extensive characteristic analysis of governing equations but can nevertheless sharply resolve discontinuities. To achieve this goal, we revisit the class of two‐state HLL schemes and show that inexpensive, accurate solvers within this class can be designed using only geometric interpretations of the Rankine–Hugoniot conditions. We argue that the small cost and nearly uniform algorithmic complexity of resulting methods make them attractive for quick computations of practical, especially very complex, problems for which more accurate solvers are either not available or their development cost is not justified. Copyright © 2002 John Wiley & Sons, Ltd.
The roles and competencies of welfare commissioners supporting children with developmental disorders and their families expected by Japan’s public health nurses

Background Public Health Nurses (PHNs) collaborate with community volunteer welfare commissioners to support children with developmental disorders and their families lead a life without isolation. Objective This study aims to clarify the roles and competencies that PHNs expect of welfare commissioners in supporting children with developmental disorders and their families. Methods An online survey was administered through Survey Monkey© to 220 PHNs working in Japanese municipalities using an independently developed questionnaire regarding the roles and competencies of welfare commissioners supporting children with developmental disorders and their families expected by PHNs. Exploratory Factor Analysis (EFA) was performed to simplify the data structure and enhance understanding. The reliability of the scale was confirmed using Cronbach’s α. Differences due to PHN attributes (e.g., experience collaborating with welfare commissioners) were analyzed using Welch’s t-test. This study was conducted between April and September 2021. Results The highest scoring items were, for the role, “a welfare commissioner’s role is to pass on accurate information to their successor,” and for competencies, “a necessary competency for a welfare commissioner is to protect the information about children with developmental disorders, and their families learned during one’s work. ” The EFA results revealed a two-factor structure for role items: Factor 1, “Supporting children with developmental disorders and their families and preventing abuse,” and Factor 2, “Connecting to social resources. ” Competency items were also found to have a two-factor structure: Factor 1, “Understanding the position of children with developmental disorders and their families and connecting with local residents,” and Factor 2, “Understanding developmental disorders and supporting them based on assessment. ” A comparison of the attributes of PHNs showed no significant differences. Conclusion PHNs feel welfare commissioners should pass on the information and protect confidentiality when supporting children with developmental disorders and their families. Furthermore, PHNs expect welfare commissioners to connect children with developmental disorders and their families to the community, prevent abuse, and provide support based on assessment. PHNs had the same expectations regarding the roles and competencies of welfare commissioners regardless of their own attributes.
Pulsating turbulent flow in a straight asymmetric diffuser

Pulsating turbulent flow is studied for four regimes: steady, quasi-steady, relaxation, and quasi-laminar in a rectangular straight asymmetric diffuser, a generic model of the diffuser found at the end of most Kaplan and Francis type hydropower turbines. The flow entering the diffuser is a developing duct flow at Reynolds number 20 000, based on mean streamwise velocity and hydraulic diameter. The time averaged velocity and turbulent quantities are not affected by the forced oscillation. The regimes prevail in the diffuser, but are shifted due to the decreasing friction velocity. The oscillating quantities are affected by the adverse pressure gradient in the same way as the time averaged quantities, but with a decreasing effect for higher forcing frequencies. The amplitude of the oscillating wall shear stress is found to be signicantly lower than the Stokes solution in the quasi-laminar regime. The regime is confirmed by the behavior of several other quantities. The pressure recovery is found to be 30% higher in the relaxation regime than in the other regimes. Results are compared with experiments in channels and turbulent boundary layers, with and without an adverse pressure gradient, and with large-eddy simulations.
Electromagnetic guided mode resonance in dielectric grating affected by transformation of refractive index periodicity

The present work studied effects of transformation of refractive index periodicity on electromagnetic wave propagation through grating waveguides. In lieu of the standard refractive index periodicity, although its unit cell consists of two kinds of materials, we consider few such unit cells as a new supercell, where the material parameters in a standard unit cell are changed. It has been shown how by changing parameters of the periodicity to control the wavelength and intensity of resonant optical mode (guided mode resonance) arising inside grating area. High quality factor calculated for the specific angle of incidence and periodicity parameter. Thus, we demonstrated that transformation of refractive index provides additional tools of controlling the GMR, and that means the sample can be designed more functional in terms of real application.
Fan Noise Reduction by Acoustic Liners Combined with Fine-Perforated-Film: Noise Tests by a Small Turbofan Engine DGEN 380

Resonant-type liner panels are one the primary countermeasures for the fan noise of aircraft engines, though the sound absorption performances of the liners are known to be tolerated by the grazing flow streaming on their surface. Therefore, suppressing the effect of the flow on the liners is greatly important for higher sound absorption efficiency. In this study, liner panels with special surface structures were manufactured and applied to an outdoor test using a small turbofan engine, DGEN 380. A special thin film, Fine-Perforated-Film (FPF), was applied to two liner samples. In the first sample, FPF was applied directly to the surface of a typical liner. In the second sample, a gap was fixed between the FPF and liner surface. In addition, a rigid wall and a typical liner were used for comparison, to investigate the effect of the structures. During the test, the samples were installed to the exhaust bypass duct of the DGEN engine. The acoustic pressure inside the duct and in far field was measured. Analysis and comparison of the results showed that the new structures suppressed the effect of the grazing flow and caused a larger amount of noise reduction, compared to the typical liner sample.
Function spaces of varying smoothness I

This paper deals with function spaces of varying smoothness. It is a modified version of corresponding parts of [8]. Corresponding spaces of positive smoothness s (x) will be considered in part II. We define the spaces B 𝕊,s 0p (ℝn ), where the function 𝕊: x ↦ s (x) is negative and determines the smoothness pointwise. First we prove basic properties and then we use different wavelet decompositions to get information about the local smoothness behavior. The main results are characterizations of the spaces B 𝕊,s 0p (ℝn ) by weighted sequence space norms of the wavelet coefficients. These assertions are used to prove an interesting connection to the so‐called two‐microlocal spaces Cs,s ′ (x0). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thickness dependence on the thermal stability of silver thin films

This study investigates the dependence of Ag resistivity on film thickness during temperature ramping as a means to access thermal stability. In situ van der Pauw four-point probe analysis is used to determine the onset temperature; the temperature when the electrical resistivity deviates from linearity during the temperature ramp. At that point, the silver thin films become unstable due to void formation and growth during thermal annealing. The thermal stability of Ag thin films on SiO2 in a vacuum is greatest when thicknesses are greater than 85 nm. Using an Arrhenius relation in terms of onset temperature and film thickness, an activation energy (0.32±0.02 eV) for the onset of agglomeration in Ag thin films on SiO2 ramped at a rate of 0.1 °C/s is determined. This value is consistent with the activation energy for surface diffusion of silver in a vacuum, which is believed to be the dominant mechanism for agglomeration of silver thin film.
Identification of multiple influential observations in logistic regression

The identification of influential observations in logistic regression has drawn a great deal of attention in recent years. Most of the available techniques like Cook's distance and difference of fits (DFFITS) are based on single-case deletion. But there is evidence that these techniques suffer from masking and swamping problems and consequently fail to detect multiple influential observations. In this paper, we have developed a new measure for the identification of multiple influential observations in logistic regression based on a generalized version of DFFITS. The advantage of the proposed method is then investigated through several well-referred data sets and a simulation study.
Simple model to explain instabilities in passively-phased high-power fiber laser arrays

We propose a simple physical mechanism to explain observed instabilities in the dynamics of passively phased fiber amplifier arrays that arises from two properties: First that a weak phase disturbance of the output field of the array is converted into a strong intensity disturbance through the mode-selective feedback mechanism. Second, that this intensity fluctuation regenerates a phase fluctuation due to the nonlinear properties of the amplifying media. At sufficiently high operating power levels this cyclic disturbance continues to grow upon each cavity round trip, creating instability. This simple picture is supported by the results of a linear stability analysis of the set of propagation and population rate equations, which are in good agreement with observed critical power levels. A third level of quantitative confirmation was obtained by comparison to the results of numerical integration of the original set of nonlinear equations. This predicted instability is entirely a property of passively phased arrays of more than one element.