Miracle-dz/UniFAR-FTUs huggingface dataset:
Resonant, Elliptical-Polarization Control of Microwave Ionization of Hydrogen Atoms

For certain ranges of the principal quantum number n{sub 0}{gt}1 a few units wide, ionization of hydrogen atoms by a 9.904GHz electric field is observed to be extremely sensitive to elliptical polarization. Classical 3D Monte Carlo calculations quantitatively reproduce the experimental data. Classical theory shows that the observed sensitivity to elliptical polarization is a resonant effect in this strongly driven quantal system. The resonant dynamics provides a mechanism for controlling the ionization. {copyright} {ital 1997} {ital The American Physical Society}
The Architecture of New Organizational Forms ∗

The recent decade’s research on organizational forms has gained important headway in converging upon a few particularly important causes of the new forms that have been observed. Yet, most studies offer no explicit definition of “organizational form,” and ignore the need to establish what should count as a “new form. ” In order to advance this research, the present paper therefore aims to provide a preliminary definition of organizational form, developed along the lines of organizational economics. A typology is provided that allows identification of alternative forms of organizing in terms of distinct architectures (topology plus dynamic rules) and a corresponding level of delegation of decision rights.
Co‐Sn substituted barium ferrite particles

Co‐Sn substituted barium ferrite particles, BaFe12−2xCoxSnxO19 (0≤x≤1.4), have been investigated using x‐ray, VSM, and Mossbauer spectroscopy. The magnetocrystalline‐anisotropy constant has been determined as a function of x from an analysis of the approach to magnetic saturation. Mossbauer spectra indicate that Co2+ and Sn4+ ions have a strong preference for the 2b, 4fVI, and 12k sites. The reduced anisotropy constants k=K1(x)/K1(0) have been calculated based on the single‐ion model and the site preferences and agree well with the measured values. The origin of the magnetic changes caused by Co2+ and Sn4+ substitution can be attributed to the site preferences.
Response Error in Earnings Functions for Nonblack Males

Biases due to measurement errors in an earnings function for nonblack males are assessed by estimating unobserved variable models with data from the Income Supplement Reinterview program of the March 1973 Current Population Survey and from the remeasurement program of the 1973 Occupational Changes in a Generation-II survey. We find that reports of social origins, educational and occupational attainments, labor supply, and earnings of nonblack males are subject to primarily random response errors. Logarithmic earnings is one of the most accurately measured indicators of socioeconomic success. Further, retrospective reports of status variables are as reliable as contemporaneous reports. When measurement errors are ignored for nonblacks, the total economic return to schooling is underestimated by about 16% and the effects of some background variables are underestimated by as much as 15%. The total effects offirst and current job status are underestimated by about 20% when measurement errors are ignored, as are the unmediated effects of current job status. Conflicting evidence is presented on whether respondents tend to understate the consistency between their earnings and educational attainments in the Current Population Survey. If there is such a tendency, unmediated effects of education are modestly understated when response errors are ignored, and they are overstated if no such tendency exists.
Exact solution of the spectrum and magneto-optics of multilayer hexagonal graphene

We demonstrate that by decoupling the interlayer interactions, N-layer hexagonal graphene is decomposed into the N independent subsystems. Each subsystem, exactly described by a 2 × 2 matrix, is treated as a renormalized graphene with the renormalized site energy and intralayer interaction. The analytical form of the energy dispersions and wave functions of each renormalized graphene is easily obtained. The study reveals the origin of electron-hole asymmetry, and how it is caused by the interlayer interaction between different sublattices at adjacent layers. The monolayer-graphene-like characteristics allow us to describe Landau-level energies and magneto-optical absorption spectra of each renormalized graphene based on the effective mass model. There are N sets of Landau levels in the energy spectra of the N-layer hexagonal graphene. The magneto-optical spectra exhibit N groups of Landau-peaks. Each group of Landau-peaks follows the same optical selection as that of a monolayer graphene.
Instantaneous closed loop control of the radiative transfer equations with applications in radiotherapy

In this paper we consider a time‐dependent Boltzmann equation for particle transport in biological tissues, which can be used for radiation dose calculation. We assume that the dose should be delivered to a target volume which moves over time. We formulate this as an optimal control problem and derive closed‐loop control laws for the dose delivery problem using boundary and distributed control. Optimality conditions are derived. For the construction of the closed‐loop control laws we use an inexact variant of model predictive control called instantaneous control. We compare numerical results obtained with instantaneous control to those obtained by optimal open‐loop control, and present numerical simulations in one and two spatial dimensions. This work could be applied to image‐guided radiation therapy, where patient motion during treatment is one of the future challenges.
Local oscillator sub-systems for array receivers in the 1-3 THz range

Recent results from the Heterodyne Instrument for the Far-Infrared (HIFI) on the Herschel Space Telescope have confirmed the usefulness of high resolution spectroscopic data for a better understanding of our Universe. This paper will explore the current status of tunable local oscillator sources with emphasis on building a multi-pixel LO subsystem for the scientifically important CII line around 1908 GHz. Recent results have shown that over 50 microwatts of output power at 1.9 THz are possible with an optimized single pixel LO chain. These power levels are now sufficient to pump array receivers in this frequency range. Further power enhancement can be obtained by cooling the chain to 120 K or by utilizing in-phase power combining technology.
Low Threshold GaInAsP/InP Distributed Feedback Lasers with Periodic Wire Active Regions Fabricated by CH 4/H 2 Reactive Ion Etching

Low damage GaInAsP/InP narrow wire structures with vertical mesa shape were realized by CH4/H2-reactive ion etching followed by a slight wet chemical etching and an embedding growth by organo-metallic vapor phase epitaxy. By using this fabrication process, a threshold current density as low as 330 A/cm2 (66 A/cm2/well, @L=860 µm) was obtained for 1.55 µm wavelength five-quantum-well distributed feedback (DFB) laser consisting of periodic wire active regions. To our knowledge this is the lowest value reported for 1.55 µm GaInAsP/InP DFB lasers fabricated by the dry etching process.
Method for analyzing the in-plane uniaxial anisotropy of soft magnetic thin film

Based on the vibrating sample magnetometer, a method is proposed to comprehensively analyze the in-plane uniaxial anisotropy of magnetic thin film. It can be used to determine accurately the values of effective anisotropy magnetic field Ha, anisotropy constants K1 and K2, as well as the directions of easy and hard axes. All of them can be carried out by fitting experimental M∕Ms-θ0 curves with theoretical equations that only require one measurement. Using this method an effective anisotropy magnetic field Ha=25.3Oe and anisotropy constants K1=2.24×104erg∕cm3 and K2=−4.7×103erg∕cm3 for the Co92Zr8 thin film were derived.
A . 2 Proofs of results in the main text

A Technical appendix A.1 Preliminaries Here we put together few standard technical results that are utilized in the main proofs. Lemma 1. Let f : Rd → R be continuously differentiable, convex, and l-smooth. Then, we have f(u)− f(v) ≤ l 2 v‖ 2 + 〈f ′(v),u− v〉 (1) ‖f ′(u)− f ′(v)‖2 ≤ 2l ( f(u)− f(v)− 〈f ′(v),u− v〉 ) . (2) Proof. Given in chapter 2 of Nesterov [8]. Lemma 2. The surrogate risk Rφ(h) defined in (7, main text), for h(x) = 〈w,x〉, w ∈ Rd, is l-smooth with coefficient l = E ‖x‖2 = vX . Proof. Assuming the order of integration and differentiation can be reversed, one can write R′ φ as
Improved multiframe association for tracking maneuvering targets

Data association is the crucial part of any multitarget tracking algorithm in a scenario with multiple closely spaced targets, low probability of detection and high false alarm rate. Multiframe assignment, which solves the data association problem as a constrained optimization, is one of the widely accepted methods to handle the measurement origin uncertainty. If the targets do not maneuver, then multiframe assignment with one or two frames will be enough to find the correct data association. However, more frames must be considered in the data association for maneuvering targets. Also, a target maneuver might be hard to detect when maneuvering index, which is the function of sampling time, is small. In this paper, we propose an improved multiframe data association with better cost calculation using backward multiple model recursion, which increases the maneuvering index. The effectiveness of the proposed algorithm is demonstrated with simulated data.
The response of a mixing layer formed between parallel streams to a concomitant excitation at two frequencies

Simultaneous excitation of a turbulent mixing layer by two frequencies, a fundamental and a subharmonic, was investigated experimentally. Plane perturbations were introduced to the flow at its origin by a small oscillating flap. The results describe two experiments that differ mainly in the amplitudes of the imposed perturbations and both are compared to the data acquired while the mixing layer was forced at a single frequency. Conventional statistical quantities such as: mean velocity profiles, widths of the flow, turbulent intensities, spectra, phase-locked velocity and vorticity fields, as well as streaklines were computed. The rate of spread of the flow under concomitant excitation at the two frequencies was much greater than under a single frequency, although it remained dominated by two-dimensional eddies. The Reynolds stresses and turbulence production are associated with the deformation and orientation of the large coherent vortices. When the major axis of the coherent vortices starts leaning forward on the high-speed side of the flow, the production of turbulent energy changes sign (i.e. becomes negative) and this results in the flow thinning in the direction of streaming. It also indicates that energy is extracted from the turbulence to the mean motion. Resonance phenomena play an important role in the evolution of the flow. A vorticity budget showed that the change in mean vorticity was mainly caused by the nonlinear interaction between coherent vorticities. Nevertheless, the locally dominant frequency scales the mean growth rate, the inclination and distortion of the mean velocity profiles as well as the phase-locked vorticity contours.
"Double-layer" method to improve image quality of industria SPECT

Recently a lab-scale single photon emission computed tomography (SPECT) system was constructed to study the details of the image formation process in an industrial SPECT system. The industrial SPECT system differs from a medical SPECT system in that it uses relatively large detectors and collimators in order to effectively detect high-energy gammas with enough collimation power, resulting always, however, in low-quality images. In this paper, a simple but very effective "double-layer" method is proposed as a means of improving the image quality of the industrial SPECT system. The rationale of the double-layer method is to simultaneously employ two layers of identical SPECT systems to increase the number of measurements points and, thereby, increase the image quality. The performance results of the double-layer method, as evaluated by Geant4 Monte Carlo simulations, showed dramatic improvement in image quality over those offered by the single-layer SPECT system. The improvement, additionally, was more marked for more complicated and higher-energy gamma sources.
A systematic polyad breaking approach to anharmonic systems

A general systematic polyad breaking approach based on Van Vleck perturbation theory is proposed for anharmonic systems where interacting Morse and/or Pöschl–Teller (PT) potentials are considered to describe molecular vibrational excitations in the framework of local mode models. Our approach is based on the algebraic representation of the Hamiltonian via the realization of the coordinates and momenta as an expansion in terms of creation and annihilation operators of Morse and/or PT functions. This algebraic representation permits to establish a perturbation expansion of the Hamiltonian suitable to apply Van Vleck perturbation theory. As an example to assess our approach a Hamiltonian of two interacting Morse oscillators with a coupling potential bilinear in the Morse coordinates is analysed in detail. Successive corrections to energies as well as to wavefunctions are presented.
Fabrication of silicon nanostructures by geometry controlled oxidation

This work presents fabrication processes of nanostructures on a top silicon layer of silicon on insulator substrates. These processes rely on the properties shown by a trapezoidal cross section, as the one obtained by anisotropic wet etching, when reduced by dry oxidation. As demonstrated by numerical simulations, oxide stress limits the oxidation process if the minor base is large enough, compared with the thickness. If instead the minor base is small, a triangular section is generated during the oxidation process and a controlled strong reduction of the cross section, until the nanometer range is possible. The fabrication of a silicon nanowire longer than 1.5 μm and with a cross section of 15 nm, obtained with this technique, is shown and demonstrated. By providing zones with different initial cross section dimensions, constrictions can be fabricated in suitable positions and controlled by oxidation reduction, so that tunnel barriers can be obtained. Room temperature electrical characterization of tunne.
Analysis of Categorical Response Profiles By Informative Summaries

A categorical profile is a vector of observed values of several categorical variables that share a common context. Statistical analysis of categorical profiles may involve study of the joint distribution of the profiles or study of the relationship of the profiles to explanatory variables. Such analysis entails special difficulties due to the very large number of possible categorical profiles and due to the very strong relationships among the responses. Given the complex nature of the relationships among the variables, large samples are required for analysis. These large samples generally render useless traditional methods of model fitting based on tests of goodness of fit. Alternatively, model quality may be assessed in terms of descriptive power, as measured by information-theoretic criteria. A useful method of data description involves summary statistics derived from the data. A new approach combining log-linear models and summary statistics results in insightful and parsimonious description of categorical profiles. The analysis of summary statistics results in the use of log-linear models that differ substantially from those commonly employed in the analysis of profile data. Special measures are introduced for comparison of the descriptive power associated with different choices of summary statistics and for comparison of the number of parameters required for each model. Estimates for these special measures are proposed, and large-sample properties are considered in order to find asymptotic confidence intervals, providing an added inferential value to the proposed methods of analysis. Through use of an empirical example of responses to questions concerning legal abortions, it is shown that models based on very succinct summaries of responses involve remarkably little information loss, thus describing the data relatively accurately and parsimoniously.
The t–J model for the oxide high-Tc superconductors

A theoretical review is given on high temperature superconductivity in copper oxides (cuprates) by focusing on the hole doping cases based on the view that it is realized in carrier doped Mott insulators, as noted by Anderson in the initial stage. From the detailed knowledge of electronic states deduced from experiments that showed the undoped parent case is Mott insulators (charge transfer type insulators, to be precise) and that the hole doping is mainly on oxygen sites, the t–J model, as derived by Zhang and Rice, is shown to be a canonical model for hole doped cuprates and values of various parameters of the model have been assessed. Results of many different numerical methods so far obtained for this t–J model, especially the variational Monte Carlo method, have clearly indicated the stability of the -wave superconductivity at absolute zero for the parameter region of actual experimental interest and the particular doping dependences of the condensation energy of superconductivity reflecting particular features of doped Mott insulators. For finite temperatures, on the other hand, the field theoretical slave-boson approximation based on the spin (spinons) and charge (holons) separations and the gauge fields as a glue combining them predicts qualitatively particular features of the existence of characteristic crossover temperatures of the spin singlet of the resonating valence bond (RVB) state, TRVB and the onset of Bose condensation of holons, TB, triggering coherent motion of electrons as convoluted particles of spinons and holons. The considerations based on the gauge field indicate that the onset temperature of superconductivity, Tc, is the lower one of these two, i.e. either TB (overdoped cases) or TRVB (underdoped cases), respectively. These characteristic features of the ‘phase diagram’ at finite temperatures are in overall agreement with various experimental observations, especially with the existence of spin-gap or pseudo-gap phases. In more detailed examinations of the underdoped region, the antiferromagnetic long-range order and superconductivity show a very intricate relationship at low temperatures depending on the system; they coexist as clarified in the inner layer of Hg-1245 but spin glass states intervene between them in La2−xSrxCuO4 (LSCO). It is argued that these differences can be attributed to the different degrees of disorder. Actually, theories based on the t–J model have also predicted the coexistence of antiferromagnetism and superconductivity in the ground state of clean systems. On the other hand, interesting experimental findings of large Nernst effect and ‘Fermi arc’ in LSCO and impurity effects in YBCO have prompted the necessity of theoretical investigations of electronic states of lightly doped Mott insulators in the presence of strong disorder.
Quantification of electromechanical coupling measured with piezoresponse force microscopy

Here, we study the piezoresponse of epitaxial ferroelectric samples excited through top electrode structures with conductive tips in the global excitation mode and compare these results to displacement values obtained using artifact-free laser Doppler vibrometry (LDV) measurements. Substrate bending modes are studied using finite element simulations and LDV measurements and found to be negligible for top electrode diameters below 100 μm. The effect of electrostatic forces on the piezoresponse measurements is analyzed and methods for minimizing these are discussed. Using a resistive tip-electrode contact mode, the piezoresponse measurements are found to be in good agreement with values obtained from calibrations, providing a link between nanometer scale piezoresponse measurements and quantitative LDV measurements.
IRAS OBSERVATIONS OF MATTER AROUND NEARBY STARS.

A systematic search of the IRAS point-source catalog has identified eight new nearby stars which are "Vega-like" in terms of their large 60-micron excess. This brings to twelve, of the set of 36 nearby dwarfs and subgiants which are bright enough to have IRAS catalog fluxes at 12, 25, and 60 microns, the total number of known Vega-like stars within 25 parsecs of the sun. Two significant effects distinguish these twelve stars from the 24 stars without 60-micron excess: The predominance of spectral type A and the absence of double stars in the Vega-like group. While both effects are intuitively consistent with the interpretation that the 60-micron excess radiation is due to a disk of protoplanetary material, suggesting an early phase in the evolution of a planetary system, this distribution can also be due to luminosity and brightness selection effects. A large fraction of the F, G, and K main-sequence stars, i.e., stars with longer main-sequence lifetimes than A stars, may thus also be surrounded by disks, but only the warmest of these disks are identifiable with high confidence in the IRAS catalog by their 60-micron excesses.
Classification of News Dataset

We used an Embedding layer of Keras to learn word embeddings, then applied convolutional layers and/or LSTM [2] layer. We also tried using pretrained GloVe embeddings [3] but the accuracy was lower then when learning embeddings from data. Surprisingly, the accuracy on dev dataset achieved by NN models (Table 2) was about the same as of logistic regression. We believe there are a few reasons for such model performance: 1) Class imbalance 2) Combination of categories in one news 3) Overlap of some news categories (e.g Politics and World news). That is why we also looked at the top 3 labels predicted by each model – in this case, maximum accuracy was 88.72% on the dev set. Results
Diffraction Effect on Phase Deviation Caused by Nonlinear Interaction between Two Sound Waves in Measuring Spatial Distribution of Nonlinearity Parameter B/A

This paper discusses the diffraction effect appearing in the phase deviation by the nonlinear interaction of sound by sound. The correction method for the diffraction effect in measuring spatial distribution of nonlinearity parameter B/A was also examined. The diffraction wave from the edge of the transducer was considered in the measurement system for the spatial distribution of B/A, in which a transducer is located in the path of another wave. The diffraction effect on the phase deviations was theoretically estimated. Numerical calculation and experiments using a simple model clarified the diffraction effect on the spatial distribution of B/A. The method for quantitative estimation and elimination of the diffraction effect was proposed. The optimal conditions for the measurement were also investigated.