Miracle-dz/UniFAR-FTUs huggingface dataset:
The development of reasoning on the balance beam

The study described in this article examined the factors in the development of reasoning on the balance beam. The results of this and other investigations by the author led to the development of a model of problem solving and of the transition between levels of performance, that is, from novice to expert behaviors in a specific problem domain. The sample for this study consisted of 34 nonscience majors enrolled in Physical Science I at the University of Southern Mississippi. The results of this study showed (a) significant correlations between the predictor variables of numerical inductive reasoning ability and ratio span and the dependent measure of amount of practice until mastery of balance beam problems, (b) that there existed significant differences on the predictors between subjects who used the ratio scheme versus those who used the product-moment rule to do balance beam problems, (c) that the sequence of behaviors until mastery of the balance beam was not invariant, and (d) that there existed significant negative correlations between individuals' tendencies to avoid unsuccessful algorithms and the frequency of incidences of monitoring the learning process on one side and the amount of practice and the construct of short-term storage space on the other side. The results of this and other studies by the author are used to develop a model of problem solving and of the development of problem-solving behaviors. This model also includes recent findings in short-term memory and problem-solving research. The implications of this model for instruction are discussed.
ERRATUM: “A MATURE DUSTY STAR-FORMING GALAXY HOSTING GRB 080607 AT z = 3.036” (2010, ApJ, 723, L218)

We have discovered an error in the photometric measurements of the host galaxy in our Spitzer IRAC images. The host is detected in the IRAC 3.5 μ m and 4.5 μ m channels with AB(3 . 5 μ ) = 22 . 9 ± 0 . 2 and AB(4 . 5 μ ) = 22 . 7 ± 0 . 2 mag. The photometric measurements of the host galaxy in other bandpasses remain unchanged. Adopting the revised Spitzer IRAC photometry and the original optical and near-IR photometric measurements, we estimate the total stellar mass ( M ∗ ) and on-going star formation rate (SFR) of the host galaxy based on the stellar population synthesis analysis described in Chen et al. Given the uncertainties in the global dust content of the host galaxy, we allow the metallicity, A V , and dust extinction law to differ from what were found in the afterglow light (e.g., Prochaska et al. 2009; Perley et al. 2011). The likelihood analysis described in Equation (1) of Chen et al. yields an extinction-corrected SFR of (8–12) h − 2 M (cid:4) yr − 1 , a mean ISM radiation ﬁeld I 0 ≈ (2 . 3–3 . 5) × 10 − 5 photons cm − 2 s − 2 Hz − 1 , and M ∗ = (0 . 5–1 . 4) × 10 10 h − 2 M (cid:4) for the host galaxy. These are about an order of magnitude lower than those originally published. We note that the uncertainties in the derived M ∗ , I 0 , and SFR are driven by the uncertainties in the global dust extinction law of the host galaxy. The galaxy is still fairly massive, but not as extreme as previously thought. The observed spectral energy distribution (SED) of the host galaxy is presented in the revised ﬁgure below, together with the best-ﬁt synthetic model of super-solar metallicity and a Milky-Way type dust extinction law of A V = 1 . 25. A Fitzpatrick & Massa (FM) law described in Perley et al. (2011) with A V = 1 . 8 and super-solar metallicity produces a similarly good ﬁt to the observed SED.
Robust fuzzy neural network controller with nonlinear disturbance observer for two-axis motion control system

A robust fuzzy neural network controller with nonlinear disturbance observer (RFNNCNDO) is proposed for the precision control of a two-axis motion control system. The adopted two-axis motion control system is composed of two permanent magnet linear synchronous motors (PMLSMs). The single-axis motion dynamics with the introduction of a lumped disturbance, which includes parameter variations, external disturbances, cross-coupled interference between the two PMLSMs and fiction force, is derived. Then, a nonlinear disturbance observer is applied to estimate the lumped disturbance and a feedback linearisation controller is adopted to stabilise the control system. However, the system responses are degraded by the existed observer error. To improve the control performance in the tracking of the reference contours, a Sugeno-type adaptive fuzzy neural network (SAFNN) is employed in the proposed RFNNCNDO to estimate the observer error directly. The online learning algorithms of the SAFNN guarantee the stability of closed-loop systems on the basis of the Lyapunov theorem. Moreover, the proposed control algorithms are implemented in a TMS320C32 digital signal processor (DSP)-based control computer. From the simulated and experimental results, the contour tracking performance of the two-axis motion control system is significantly improved and the robustness can be obtained as well using the proposed RFNNCNDO control system.
Wave propagation in anisotropic liquid‐saturated porous solids

Biot’s theory is employed to study the propagation of plane‐harmonic seismic waves in a transversely isotropic liquid‐saturated porous solid. Along with SH wave, the existence of three quasiwaves is discussed and analytical expressions for their velocities of propagation have been obtained. It has been observed that velocities of existing waves vary with the direction of propagation. Frequency equation for the propagation of Rayleigh‐type surface waves at the free surface of transversely isotropic liquid‐saturated porous solids has been obtained. Possibilities of existence of body waves and surface waves have been discussed numerically by assuming different sets of values of elastic constants. Dependence of the velocities of propagation on the direction of propagation has been exhibited.
Fully polarimetric scattering from random rough layers under the geometric optics approximation: Geoscience applications

Predictions of the geometric optics approximation for scattering from two rough interfaces that separate three homogeneous media (the “GO‐layer” model) are examined for their implications for radar remote sensing. A previous formulation of the rough layer normalized radar cross section (NRCS) is also extended to allow calculation of the polarimetric covariance of the scattered field. Example results are presented for both bistatic and monostatic configurations, and show the influence of subsurface interfaces on scattered field properties. In particular, complete hemispherical bistatic patterns of both NRCS and polarimetric correlations are illustrated to provide insight into the impact of subsurface layers on these quantities. It is shown that the observability of sub‐surface contributions in general is larger for geometries where upper interface returns are smaller (i.e. angles outside the quasi‐specular return of the upper interface), and it is also shown that significant decorrelations between polarizations can occur in the presence of sub‐surface layers. Variations of field properties with medium physical parameters (inner layer thickness and relative permittivity, upper and lower surface RMS slopes, radar frequency) are also shown. A problem that has received extensive previous interest (subsurface sensing in arid regions having an upper sand layer over a granite bedrock) is re‐examined for remote sensing at higher frequencies, and it is shown that subsurface contributions can impact backscattered NRCS returns even up to X‐band frequencies. The examples presented can be utilized to assess the potential detectability of sub‐surface layers for both monostatic radar observations and near specular observations (as in GNSS reflection observations of land surfaces).
Gain induced optical transparency in metamaterials

We demonstrate that fluorophores coupled to plasmonic nanoparticles promote resonant excitation energy transfer processes leading to low-loss building block metamaterials. Experimental observations of Rayleigh scattering enhancement, accompanied by an increase in transmission as function of the gain, clearly reveal optical loss compensation effects. Fluorescence quenching is also observed in gain assisted nanoparticles owing to the increase in nonradiative decay rate triggered by plasmonic resonances. The gain induced transparency at optical frequencies is an unambiguous consequence of loss reduction in metamaterial subunits, representing a promising step to enable a wide range of electromagnetic properties of optical metamaterials.
A dual formulation of a penalized maximum likelihood x-ray CT reconstruction problem

This work studies the dual formulation of a penalized maximum likelihood reconstruction problem in x-ray CT. The primal objective function is a Poisson log-likelihood combined with a weighted cross-entropy penalty term. The dual formulation of the primal optimization problem is then derived and the optimization procedure outlined. The dual formulation better exploits the structure of the problem, which translates to faster convergence of iterative reconstruction algorithms. A gradient descent algorithm is implemented for solving the dual problem and its performance is compared with the filtered back-projection algorithm, and with the primal formulation optimized by using surrogate functions. The 3D XCAT phantom and an analytical x-ray CT simulator are used to generate noise-free and noisy CT projection data set with monochromatic and polychromatic x-ray spectrums. The reconstructed images from the dual formulation delineate the internal structures at early iterations better than the primal formulation using surrogate functions. However the body contour is slower to converge in the dual than in the primal formulation. The dual formulation demonstrate better noise-resolution tradeoff near the internal organs than the primal formulation. Since the surrogate functions in general can provide a diagonal approximation of the Hessian matrix of the objective function, further convergence speed up may be achieved by deriving the surrogate function of the dual objective function.
Frequency-Domain Method for the Computation of Propeller Acoustics

In the present study an analytical description of the acoustic field of a propeller in a uniform flow is derived. Instead of applying the usual Ffowcs-Williams-Hawkings version of the acoustic analogy, here we formulate sources on a surface enclosing the propeller and its adjacent nonlinear flowfield. This approach, which avoids the laborious evaluation of quadrupole source terms, is to be considered as a generalization of the Kirchhoff-Helmholtz theorem of acoustics. By describing the fundamental solution as a spectral Fourier-Bessel decomposition, the resulting sound field is readily given in the appropriate series of harmonic amplitudes. The method is validated by a comparison of numerical results with experimental data of a propeller in an acoustic wind tunnel. A good agreement both in amplitude and phase is found between theory and experiment.
An accurate nonlinear stochastic model for MEMS-based inertial sensor error with wavelet networks

Abstract The integration of Global Positioning System (GPS) with Inertial Navigation System (INS) has been widely used in many applications for positioning and orientation purposes. Traditionally, random walk (RW), Gauss-Markov (GM), and autoregressive (AR) processes have been used to develop the stochastic model in classical Kalman filters. The main disadvantage of classical Kalman filter is the potentially unstable linearization of the nonlinear dynamic system. Consequently, a nonlinear stochastic model is not optimal in derivative-based filters due to the expected linearization error. With a derivativeless-based filter such as the unscented Kalman filter or the divided difference filter, the filtering process of a complicated highly nonlinear dynamic system is possible without linearization error. This paper develops a novel nonlinear stochastic model for inertial sensor error using a wavelet network (WN). A wavelet network is a highly nonlinear model, which has recently been introduced as a powerful tool for modelling and prediction. Static and kinematic data sets are collected using a MEMS-based IMU (DQI-100) to develop the stochastic model in the static mode and then implement it in the kinematic mode. The derivativeless-based filtering method using GM, AR, and the proposed WN-based processes are used to validate the new model. It is shown that the first-order WN-based nonlinear stochastic model gives superior positioning results to the first-order GM and AR models with an overall improvement of 30% when 30 and 60 seconds GPS outages are introduced.
Randomized algorithms for probabilistic robustness with structured uncertainty

In this paper, randomized algorithms for stability and performance of linear time invariant uncertain systems described by a general M-/spl Delta/ configuration are studied. On the contrary of the worst-case approach, which is often not tractable in the NP-hardness sense, this problem turns out to be solvable in a probabilistic setting. In particular, efficient polynomial-time algorithms for uncertainty structures /spl Delta/ consisting of an arbitrary number of full complex blocks and uncertain parameters, real or complex and possibly repeated, are developed.
Correlator measurements of megahertz wave‐particle interactions during electron beam operations on STS

We report on the analysis of megahertz modulation of electrons as measured by the Shuttle Potential and Return Electron Experiment (SPREE) during dc firing of the shuttle electrodynamic tether system (SETS) fast pulsed electron generator (FPEG). The SPREE and FPEG were flown aboard the space shuttle Atlantis flight STS 46 as part of the Tethered Satellite System (TSS 1) mission. The principal data reported here are from the SPREE multiangular electrostatic analyzers (ESAs) and Space Particle Correlator Experiment (SPACE). The ESAs, mounted on rotary tables, measured electrons and ions in the energy range from 10 eV to 10 keV over a solid angle of 2π sr. The SPACE is a signal processing system that analyzes the pulse stream from the SPREE ESAs to identify bunching of the electrons and ions produced by coherent wave-particle interactions (WPIs). The SPACE detects modulations in the electron fluxes in frequency range 0- to 10-MHz. This paper concerns 2- to 4-MHz modulations of the electron flux detected by the SPACE when the FPEG was firing in a dc mode at pitch angles close to 90°. During such operations, FPEG emitted a current of 100 mA at an energy of 1 keV. For these times, electrons with energies from 10 to 1850 eV were measured by the SPREE. For energies between ∼10 and 100 eV the electron flux is basically isotropic. At higher energies the flux increases for pitch angles near 90°. The electron distribution functions generally decrease monotonically with increasing energy up to 100 eV. At energies >100 eV the distributions either monotonically decrease or exhibit a peak or plateau at energies near the beam emission energy. Megahertz modulations were observed for electrons with energies from 10 to 1180 eV, on both positive and negative slopes in the distribution function and throughout the 2π sr sampled by the ESAs. The occurrence and strength of the modulations exhibit no clear dependence on the pitch angle at which the electrons are measured. However, they appear to be limited to low parallel velocities (<3×10 6 m s −1 ) where beam-generated waves are in resonance with suprathermal electrons.
Short-period geomagnetic secular variation

Abstract In this paper the main problems of the theory of the short-period geomagnetic secular variation are described. An approximate analytical representation of the observational data on both the geomagnetic field variations and the associated variations in the length of the day, the kinematics of the generation of geomagnetic variations in the skin-layer at the core-mantle boundary and the influence of the electrical conductivity of the mantle on the geomagnetic variations are considered. A theory of torsional oscillations in the Earth's core is developed and an attempt is made to evaluate the associated geomagnetic variations. Magnetohydrodynamic effects in a possible thin layer of stably stratified fluid near the core-mantle boundary are investigated.
Polarization-dependent reflectivity from dielectric nanowires

The presence of GaN nanowires grown primarily normal to the surface of a sapphire substrate has a dramatic influence on the polarization dependence of laser light reflectivity at λ=1550-nm wavelength. Even at 12% substrate surface coverage, there is a factor of 2 enhancement in polarization dependence of reflectivity relative to bulk sapphire at values of incident angle greater than φ=72°.
MAP/(PH/PH)/c Queue with Self-Generation of Priorities and Non-Preemptive Service

Abstract Customers arriving according to a Markovian arrival process are served at a c server facility. Waiting customers generate into priority while waiting in the system (self-generation of priorities), at a constant rate γ; such a customer is immediately taken for service, if at least one of the servers is free. Else it waits at a waiting space of capacity c exclusively for priority generated customers, provided there is vacancy. A customer in service is not preempted to accommodate a priority generated customer. The service times of ordinary and priority generated customers follow distinct PH-distributions. It is proved that the system is always stable. We provide a numerical procedure to compute the optimal number of servers to be employed to minimize the loss to the system. Several performance measures are evaluated.
Compact hyperbolic coxeter thin cubes

Andreev’s Theorem provides a complete characterization of 3-dimensional compact hyperbolic combinatorial polytope having non-obtuse dihedral angles. Cube is one of such polytope. In this article, with the help of Andreev’s Theorem, a special type of compact hyperbolic coxeter cube, called thin cube has been studied. Using graph theory and combinatorics, it has been found that there are exactly 3 such cubes in hyperbolic space upto symmetry.
On the sensitivity of generalized state-space systems

The synthesis of minimum-sensitivity state-space realizations of linear time-invariant systems is a well understood problem. Such realizations have been linked to balanced realizations. The theory is extended to the synthesis of minimum-sensitivity generalized state-space models for singular linear systems. A scalar sensitivity measure is defined, and the minimization of the measure over all admissible realizations is considered. Since minimal realizations are not required to be related by a similarity transformation, the optimization problem is more complex. A criterion is given for determining optimal sensitivity structures. In the nonsingular case, the criterion reduces to the familiar result. The simple example of the right-shift operator is considered. <<ETX>>
A low complexity halo reduction method for motion compensated frame interpolation

This paper proposed a low complexity halo reduction method for motion compensated frame interpolation which bases on only two successive frames. An improved forward and backward jointing motion estimation method that features a faster convergence speed is utilized to produce the motion vector fields of the original frames. These motion vector fields are retimed to the to-be-interpolated frame to calculate the motion vector field for interpolation and to get the coarse location of the new exposed areas. Through analyzing the relationship of the adjacent motion vectors, two general equations are generated for the covered and uncovered blocks, and occlusion areas are further refined. Finally, unidirectional interpolation and bi-directional interpolation are combined to avoid the halos and block artifacts. Experimental results show that the proposed algorithm achieves much better image quality than that without halo reduction processing.
Subgrid modeling in particle-laden channel flow

Direct numerical simulation (DNS) and large-eddy simulation (LES) of particle-laden turbulent channel flow, in which the particles experience a drag force, are investigated for two subgrid models and several Reynolds and Stokes numbers. In this flow, turbophoresis leads to an accumulation of particles near the walls. The objectives of the work are to investigate the accuracy of the subgrid models studied with respect to particle behavior and to explain the observed particle behavior predicted by the different models. The focus is on particle dispersion and mean particle motion in the direction normal to the walls of the channel. For a low Reynolds number, it is shown that the turbophoresis and particle velocity fluctuations are reduced compared to DNS, if the filtered fluid velocity calculated in the LES is used in the particle equation of motion. This is a combined effect of the disregard of the subgrid scales in the fluid velocity and the inadequacy of the subgrid model. Better agreement with DNS is obt.
POSSIBLE APSIDAL MOTION OF THE ECLIPSING VARIABLE BD + 31° 3932

observed for an eclipsing variable. Apsidal motion is excluded because both minima show the same trend, being separated from each other by one-half the period. Since the secondary minimum is not so deep as the primary, the number of usable minima is smaller for the secondary than for the primary. We concur with the remarks of Dugan and Wright about this stupendous change in period and add that the “expected” change in behavior of the binary has not yet ensued. The period is still decreasing about 0.0001 day within a thousand days.
HIGH-RESOLUTION IUE SPECTROSCOPY OF FAST WINDS FROM CATACLYSMIC VARIABLES

The winds from six dwarf novae and four nova-like cataclysmic variables are studied using 31 high-resolution IUE spectra. The data provide details on the time- and phase-averaged nature of disc-driven outflows, which are diagnosed via the presence of P Cygni-like and extended absorption profiles due to the C IV, N V and Si IV resonance line doublets, and He II lambda 1640. The profiles are parametrized using measures of the absorption and emission velocities, widths and strengths. The maximum wind velocity can exceed -4000 km s(-1), although the absorption maximum (minimum flux) typically occurs at similar to 20 per cent of the shortward profile edge. Optical depth and velocity structure is identified in the absorption troughs which may indicate inhomogeneities in the outflows. The relative ion behaviour and the respective contributions to the emission profiles of the inner disc and wind are discussed. Synthesized model profiles are used to estimate the products of mass-loss rate and C3+ ion fractions.
A sequence of physical processes determined and quantified in LAOS: Application to a yield stress fluid

Recently, large-amplitude oscillatory shear has been studied in great detail with emphasis on its impact on the material response. Here we present a conceptually different, robust methodology based on viewing the stress waveforms as representing a sequence of physical processes. This novel approach provides the viscous and elastic contributions while overcoming the problems with infinite series encountered by Fourier transformation. Application to a soft colloidal star glass leads to the unambiguous determination and quantification of rate-dependent static and dynamic yield stresses, the rationalization of the response to strain sweeps and the post-yield regime by introducing the apparent cage modulus, and a connection to the steady-shear stress, all from a single-amplitude experiment. We propose that this approach is generic, but focus in this contribution only on a yield stress material which exhibits repeating cycles of (i) elastic extension, (ii) yielding, (iii) flow, and (iv) reformation. We show tha.