Miracle-dz/UniFAR-FTUs huggingface dataset:
Improved layout for a resonant 2D micro scanning mirror with low operation voltages

The Fraunhofer Institute of Microelectronic Circuits and Systems, Dresden, has been developing resonant Micro Scanning Mirrors for several years. They are designed for large deflection angles at low driving voltages in resonant operation. A couple of changes and optimizations in the layout of the 2-scanner that have improved performance and reliability are presented and discussed. Different variants have been fabricated by bulk-micromachining in bonded silicon-on-insulator-substrates and have been characterized. Mirror plate and gimbal can be rectangular or elliptical, now. New comb structures of the driving electrodes allow optimization of either capacitance, damping or electromechanical stability. Complex insulation structures reduce parasitic capacitance and increase reliability and mechanical stability. Various design variants were fabricated and characterized. Low-frequency devices with characteristic frequencies under 500 Hz reached scan ranges over 45° (±11.2 degrees mechanically) at voltages below 20V. The high-frequency devices with 8.4 kHz / 1 kHz reached 17.5° / 35° at 40 V / 30 V, respectively.
Polynomial representations from abstract perturbed Krylov methods

We present the framework of “abstract perturbed Krylov methods”, a new, unified point of view on different types of Krylov subspace methods. We give a brief informal sketch of polynomial representations of QOR approximations to solutions of linear systems and eigenvectors. The results are applicable to exact arithmetic, finite precision computations including semiduality approaches, and inexact methods. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Video Analytics Algorithm for Automatic Vehicle Classification (Intelligent Transport System)

Automated Vehicle detection and classification is an important component of intelligent transport system. Due to significant importance in various fields such as traffic accidents avoidance, toll collection, congestion avoidance, terrorist activities monitoring, security and surveillance systems, intelligent transport system has become important field of study. Various technologies have been used for detecting and classifying vehicles automatically. Automated vehicle detection is broadly divided into two types- Hardware based and software based detection. Various algorithms have been implemented to classify different vehicles from videos. In this paper an efficient and economical solution for automatic vehicle detection and classification is proposed. The proposed system first isolates the object through background subtraction followed by vehicle detection using ontology. Vehicle detection is based on low level features such as shape, size, and spatial location. Finally system classifies vehicles into one of the known classes of vehicle based on size.
The electron-impact ionization of ions

The absolute cross section for the ionization of from threshold to 400 eV has been measured using an electron beam modulation technique. The results are significantly higher than those of Crandall et al, and are in good agreement with recent convergent close-coupling and pseudo-state R-matrix calculations by Badnell et al for the direct contribution to the cross section below 80 eV. In addition, a fast energy-scanning technique has been employed to make detailed measurements of the cross section between 65 and 117 eV. Considerable structure due to indirect ionization was revealed and many of the individual features can be identified with particular autoionization processes involving the excitation of a 2p electron.
Factorial One-Factor-at-a-Time Experiments

Abstract Factorial experiments are done to measure the average effects of varying each of several factors (experimental conditions, independent variables) over fixed ranges of the other factors. Factors at two levels only are considered here. The system under study is assumed to permit the variation of only one factor per trial. Up to four factors may be of interest. The sequences proposed, of sizes 7–9, are easy to remember, simple to analyze, and straightforward to augment. Each result is compared with its immediate predecessor or successor only. Thus the three-factor one-at-a-time factorial follows the sequence. (1)1, a, ab, abc, bc, c, (1)2, where (1) means all factors at their low levels; a means 1 factor, A, at its high level; ab means A and B at high levels; and so forth.
High-precision cryogenic wheel mechanisms for the JWST NIRSpec instrument

The Grating and Filter Wheel Mechanisms of the JWST NIRSpec instrument allow for reconfiguration of the spectrograph in space in a number of NIR sub-bands and spectral resolutions. Challenging requirements need to be met simultaneously including high launch loads, the large temperature shift to cryo-space, high position repeatability and minimum deformation of the mounted optics. The design concept of the NIRSpec wheel mechanisms is based on the ISOPHOT Filter Wheels but with significant enhancements to support much larger optics. A well-balanced set of design parameters was to be found and a considerable effort was spent to adjust the hardware within narrow tolerances.
OUTLIER DIAGNOSTICS IN TIME SERIES ANALYSIS

Cook's likelihood displacement is a convenient measure of the impact of a model perturbation on parameter estimates. A commonly used model perturbation in regression is the deletion of a case, or equation. A natural model perturbation in the time series context is the deletion of an observation, or a group of observations. Diagnostics that measure the impact of individual observations on the time series estimates are explored in this paper. A diagnostic that compares the estimates of the innovation variance with and without a particular observation is studied in detail.
Estimation of Cointegration Vectors with Linear Restrictions

A general approach for the estimation of cointegration vectors with linear restrictions is described. In the special case of zero restrictions, the cointegration relations of the paper are formally similar to the structural form of a traditional simultaneous equation model. The proposed estimation procedures require a conventional rank condition of identification but no exogeneity assumption. In place of exogenous variables there are series that are not cointegrated and can therefore describe the common trends in the system. The estimators of the paper are flexible and simple to use. They can be combined with several recent estimators developed for cointegration regressions which in the present context are formally similar to the reduced form of a simultaneous equation model. After the coefficient matrix of a cointegration regression has been estimated, the estimators of the paper can be obtained by simple generalized least squares. Both single equation estimators and more efficient system estimators are developed. The asymptotic distributions of the estimators are shown to be mixed normal so that Wald tests with asymptotic chi-square distributions under the null hypothesis can be obtained in the usual way. Convenient test procedures for checking the validity of overidentification restrictions are also provided.
Irradiation of the secondary star in cataclysmic variables

It is shown how the relative strength of the Na I doublet over the surface of the secondary star can be calculated from radial velocity curves obtained using the Na I absorption feature around 8190 A. The results for 11 dwarf novae and one magnetic cataclysmic binary system are presented. For the five dwarf nova secondary stars that showed significant heating, it is found that the surface distribution is far more asymmetrical than would be expected from irradiation by the white dwarf and disc hotspot
The Impact of Star Formation on the Interstellar Medium. I. The Excitation of Diffuse, Warm Ionized Gas in Dwarf Galaxies

I present measurements of optical emission-line ratios from long-slit spectra of 14 star-forming dwarf galaxies. All members of the sample have a prominent component of diffuse warm ionized gas (DIG). Spectra of the DIG are characterized by high [O I]/Hα intensity ratios in addition to high [O II]/[O III], [S II]/Hα, [N II]/Hα, and low [O III]/Hβ ratios relative to the H II regions. Measurements from ~350 spectra extracted at spatial intervals of ~20-150 pc show that this spectral change is gradual and continuous; hence, the boundary between H II regions and DIG is not well defined spectroscopically. In diagnostic line-ratio diagrams, the spectral transition advances along a narrow track that is distinctly different from the well-established H II region excitation sequence. The line ratios progress toward the region populated by weak-[O I] Low-Ionization Nuclear Emission-Line Regions. I show that this H II-DIG transition sequence is driven primarily by a decrease in the relative density of ionizing photons to atoms, i.e., the ionization parameter. The radial gradient in the ionization parameter is consistent with the dilution of radiation from a centralized source. This result suggests that the dominant excitation mechanism of the DIG is photoionization by massive stars associated with the main star-forming regions. In several of the galaxies, however, an additional excitation mechanism is required to explain the moderately high [O III]/Hβ at very high [S II]/Hα and the sharp increase in [O I]/Hα with only a moderate increase in [O II]/[O III]. I show that these line ratios can be explained by a contribution to the emission from shock-excited gas. The inferred shock speeds are between 60 km s-1 and 100 km s-1; the line ratios in the regions with the lowest surface brightness require the largest relative contribution from shocks, up to 30%-50% of the emission. The prevalence of a secondary emission component from shocked gas is difficult to quantify. Where the metallicity is very low and/or the shock speed is ≲60 km s-1, the line ratios alone cannot distinguish emission from shocked gas from that from dilute H II regions. Among the galaxies, differences in the DIG line ratios can be largely attributed to the galactic metallicity. At similar metallicity, however, spectral differences are related to the ionization parameter and ionization state of the parent H II regions. This result provides direct evidence that star formation affects the structure of the interstellar medium on a global scale. I find that much of the observed variation in H II region ionization parameters is caused by substantial differences in their filling factors of warm ionized clouds. Based on these results, I suggest that the DIG spectra reflect the porosity of the star-forming regions.
The BATSE Rapid Burst Response system

The recently developed BATSE Rapid Burst Response (RBR) system provides gamma-ray burst locations accurate to ∼2°–3° for several bursts per month within ∼15–35 minutes of onset. Combined with wide-field or scanning instruments, this system offers the chance of detecting prompt x-ray/optical/radio afterglow emission from many bursts. We discuss the operation, performance and status of the BATSE RBR system as well as results from coordinated multi-wavelength follow-up observations.
The Buckling of an Elastic Layer Bonded to an Elastic Substrate in Plane Strain

The results are compared to an approximate solution that models the layer using beam theory. This comparison shows that the beam theory model is adequate until the buckling strain exceeds three percent, which occurs for modulus ratios less than 100. In these cases the beam theory predicts a larger buckling strain than the exact solution. In all cases the wavelength of the buckled shape is accurately predicted by the beam model. A buckling experiment is described and a discussion of buckling induced delamination is given
Nonparametric Mixed Ratio Estimator for a Finite Population Total in Stratified Sampling

We propose a nonparametric regression approach to the estimation of a finite population total in model based frameworks in the case of stratified sampling. Similar work has been done, by Nadaraya and Watson (1964), Hansen et al (1983), and Breidt and Opsomer (2000). Our point of departure from these works is at selection of the sampling weights within every stratum, where we treat the individual strata as compact Abelian groups and demonstrate that the resulting proposed estimator is easier to compute. We also make use of mixed ratios but this time not in the contexts of simple random sampling or two stage cluster sampling, but in stratified sampling schemes, where a void still exists.
Two-dimensional modeling of positive streamer propagation in flue gases in sphere-plane gaps

The results of two-dimensional numerical simulation of positive streamer dynamics in flue gases in sphere-plane electrode configuration are presented. The G-values (numbers of radicals produced per 100 eV of input electrical energy) for the production of chemically active particles participating in flue gas cleaning from toxic components are calculated. Obtained G-values are almost independent on the discharge conditions. Simple estimates for G-values, based on analytical streamer theory, are shown to agree with the results of numerical simulation.
A multiclass feedback queue in heavy traffic

We consider a single station queueing system with several customer classes. Each customer class has its own arrival process. The total service requirement of each customer is divided into a (possibly) random number of service quanta, where the distribution of each quantum may depend on the customer's class and the other quanta of that customer. The service discipline is round-robin, with random quanta. We prove a heavy traffic limit theorem for the above system which states that as the traffic intensity approaches unity, properly normalized sequences of queue length and sojourn time processes converge weakly to one-dimensional reflected Brownian motion.
Review of video action recognition technology based on deep learning

: Action recognition(AR) is a hot research area in computer vision field, and has an extensive application prospect for security monitoring, autopilot, production safety etc. Firstly, this paper analysed the connotation and denotation of AR and put forward the technical challenges; Secondly, the paper analysed and compared the working principles of AR from three aspects: time feature extraction, efficient optimization and long-term feature capture; Thirdly, in order to select suitable AR models for different application scenarios, this paper compared the performance characterization of 43 benchmark AR methods in recent ten years based on UCF101, HMDB51, Something-Something and Kinetics400 data sets. Finally, this paper pointed out the future development direction of AR field, and the research results can provide theoretical reference and technical support for video feature extraction and visual content understanding.
TORUS KNOTS EMBODYING CURVATURE AND TORSION IN AN OTHERWISE FEATURELESS CONTINUUM

The subject is a localized disturbance in the form of a torus knot of an otherwise featureless continuum. The knot's topologically quantized, self-sustaining nature emerges in an elementary, straightforward way on the basis of a simple geometric model, one that constrains the differential geometric basis it otherwise shares with General Relativity (GR). Two approaches are employed to generate the knot's solitonic nature, one emphasizing basic differential geometry and the other based on a Lagrangian. The relationship to GR is also examined, especially in terms of the formulation of an energy density for the Lagrangian. The emergent knot formalism is used to derive estimates of some measurable quantities for a certain elementary particle model documented in previous publications. Also emerging is the compatibility of the torus knot formalism and, by extension, that of the cited particle model, with general relativity as well as with the Dirac theoretic notion of antiparticles.
Time-periodic quasi-linear reaction-diffusion equations

A resonance result for a time-periodic quasi-linear reaction-diffusion system with (possibly) different diffusion coefficients is established. The driving force of the system may depend upon the dependent variables as well as their derivatives. Also a nonresonance result below the common first associated eigenvalue is stated and proved, and an example of an autocatalytic system illustrating this result is presented. Two other examples for the resonance result are also presented.
Least squares parameter estimation of continuous-time ARX models from discrete-time data

When modeling a system from discrete-time data, a continuous-time parameterization is desirable in some situations, In a direct estimation approach, the derivatives are approximated by appropriate differences. For an ARX model this lead to a linear regression. The well-known least squares method would then be very desirable since it can have good numerical properties and low computational burden, in particular for fast or nonuniform sampling. It is examined under what conditions a least squares fit for this linear regression will give adequate results for an ARX model. The choice of derivative approximation is crucial for this approach to be useful. Standard approximations like Euler backward or Euler forward cannot be used directly. The precise conditions on the derivative approximation are derived and analyzed. It is shown that if the highest order derivative is selected with care, a least squares estimate will be accurate. The theoretical analysis is complemented by some numerical examples which provide further insight into the choice of derivative approximation.
Interstellar scattering of the compact radio source 2005 + 403

Analysis of Mk III VLBI visibility amplitudes of the compact radio source 2005 + 403 shows an excess at baselines greater than a few diffractive scale lengths compared with that expected from formulas using ensemble-averaged quantities and power-law turbulence with quasi-Kolmogorov spectral indices. The data are in good agreement with the 1989 analysis of Goodman and Narayan, who find that measured visibility amplitudes correspond to the average visibility regime, which differs significantly from the ensemble-averaged results for baselines much longer than one diffractive scale length. 20 refs.
The Magellan Telescope Adaptive Secondary AO System: a visible and mid-IR AO facility

The Magellan Clay telescope is a 6.5m Gregorian telescope located in Chile at Las Campanas Observatory. The Gregorian design allows for an adaptive secondary mirror that can be tested off-sky in a straightforward manner. We have fabricated a 85 cm diameter aspheric adaptive secondary with our subcontractors and partners, the ASM passed acceptance tests in July 2010. This secondary has 585 actuators with <1 msec response times (0.7 ms typically). This adaptive secondary will allow low emissivity AO science. We will achieve very high Strehls (~98%) in the Mid-IR (3-26 microns) with the BLINC/MIRAC4 Mid-IR science camera. This will allow the first "super-resolution" and nulling Mid-IR studies of dusty southern objects. We will employ a high order (585 mode) pyramid wavefront sensor similar to that now successfully used at the Large Binocular Telescope. The relatively high actuator count will allow modest Strehls to be obtained in the visible (0.63-1.05 μm). Moderate (~20%) Strehls have already been obtained at 0.8 μm at the LBT with the same powerful combination of a next generation ASM and Pyramid WFS as we are providing for Magellan. Our visible light AO (VisAO) science camera is fed by an advanced triplet ADC and is piggy-backed on the WFS optical board. We have designed an additional "clean-up" very fast (2 kHz) tilt stabilization system for VisAO. Also a high-speed shutter will be used to block periods of poor correction. The VisAO facility can be reconfigured to feed an optical IFU spectrograph with 20 mas spaxels. The entire system passed CDR in June 2009, and is now finished the fabrication phase and is entering the integration phase. The system science and performance requirements, and an overview the design, interface and schedule for the Magellan AO system are presented here.
Polarisation effects of the dynamical Stark effect of excitons in quantum wells

The authors study the polarisation properties of the dynamical Stark effect of excitons in semiconductor quantum wells. They start from a four-band density matrix theory involving the heavy- and light-hole band and the two lowest conduction subbands. The set of equations of motion contains the dynamics relevant for both Frohlich-type experiments (pumping with a carbon dioxide laser) and the case of pumping a few exciton rydbergs below the exciton line. The authors perform the relevant projections based on excitonic eigenstates and study the resulting 'few-level' systems. From this they calculate the change in the susceptibility tensor with respect to a weak probe beam caused by a pump beam with specified polarisation and frequency.
Time-dependent scaling relations and a cascade model of turbulence

We study the time-dependent solutions of a nonlinear cascade model for homogeneous isotropic turbulence first introduced by Novikov & Desnyansky. The dynamical variables of the model are the turbulent kinetic energies in discrete wave-number shells of thickness one octave. The model equations contain a parameter C whose size governs the amount of energy cascaded to small wavenumbers relative to the amount cascaded to large wavenumbers. We show that the equations permit scale-similar evolution of the energy spectrum. For 0 ≤ C ≤ 1 and no external force, the freely evolving energy spectrum displays the Kolmogorov k power law, and the total energy decreases in time as a power t−w, where the exponent w depends on the value of C. Grid-turbulence experiments seem to favour a value of C in the range 0·3-0·6. In the presence of an external stirring force acting near a wavenumber k0, the model predicts, in addition to the Kolmogorov k spectrum for k > k0, a scale-similar flow of energy to wavenumbers k < k0. This backward energy flow falls off as a power law in time, and establishes a stationary energy spectrum for k < k0 which is a power law in k less steep than k. We discuss the similarity of the behaviour of the model for C > 1 to the behaviour of turbulent fluid for a spatial dimensionality near 2. The model is shown to approach the Kovasznay and the Leith diffusion approximation equations in the limit in which the thickness of the wavenumber shells approaches zero. However, the cascade model with finite shell thicknesses appears to behave in a more physically reasonable way than the limiting differential equations.
Error Analysis of the Finite-Volume Method with Respect to Mesh Type

This article presents truncation error terms for flux approximations on mesh faces, needed by the finite-volume method, and their influence on solution accuracy in the search for the optimal cell type. Face truncation errors are used to assemble truncation errors for different cell types such as squares, triangles, and hexagons. It is shown that squares have the smallest and triangles the largest truncation errors, for the same cell size, which is also confirmed by numerical experiments. It is also shown that polyhedral meshes consisting of hexagons are slightly less accurate than hexahedral meshes with the same cell size.