Miracle-dz/UniFAR-FTUs huggingface dataset:
In-plane and out-of-plane uniaxial anisotropies in rectangular arrays of circular dots studied by ferromagnetic resonance

Ferromagnetic resonance at 9.2 GHz (X band) was used to characterize the uniaxial magnetic anisotropies in rectangular arrays of submicron circular Ni dots. The in-plane anisotropy, originated from interdot interactions in the rectangular lattice, and the perpendicular anisotropy, due to individual dot shape and magnetostriction, were explored. For in-plane dependencies of the resonance field (Hr), the main resonance mode angular dependence was well described by the standard Kittel formula. As the interdot distances decreased from 800 to 50 nm, the in-plane uniaxial anisotropy field changed from 5 to 130 Oe, in reasonable agreement with calculations. Simultaneously, the position of perpendicular Hr increased from 6.38 to 6.83 kOe, also following Kittel’s formula.
Evidence for redshift periodicity in nearby field galaxies

The claim by Tifft and colleagues (1984, ApJ, 287) that extragalactic redshifts are periodic in ranges around 24.2, 36.3 or 72.5 km/s was investigated for an independent sample of 89 nearby spirals, in the general field, with accurately determined heliocentric redshifts. Corrections were applied for a range of solar vectors encompassing various derivations of the solar motion relative to the Galactic Centre and the centroid of the Local Group, and power spectrum analyses were carried out on the sets of corrected redshifts. A strong periodicity of ∼37.2 km/s emerged, against a white noise background, for an assumed solar vector coincidental, within the uncertainties, with that corresponding to the Sun's probable motion around the Galactic Centre
Polarization spectroscopy of x-ray transitions from beam-excited highly charged ions

Polarization spectroscopy of x-ray lines represents a diagnostic tool to ascertain the presence of electron beams in high-temperature plasmas. Making use of the Livermore electron beam ion trap, which optimizes the linear x-ray line polarization by exciting highly charged ions with a monoenergetic electron beam, we have begun to develop polarization diagnostics and test theoretical models. Our measurement relies on the sensitivity of crystal spectrometers to the linear polarization of x-ray lines which depends on the value of the Bragg angle. We employed two spectrometers with differing analyzing crystals and simultaneously recorded the K-shell emission from heliumlike Fe24+ and lithiumlike Fe23+ ions at two different Bragg angles. A clear difference in the relative intensities of the dominant transitions is observed, which is attributed to the amount of linear polarization of the individual lines.
One Tbps superchannel generated by Optical Flat Comb Source WDM-Nyquist and OFDM system simulative investigation

In this paper, we implement an Optical Flat Comb Source generating a coherent super-channel operating at 1 Tbps using WDM-Nyquist and OFDM approaches with new flex-grid channel spacing. The new flex-grid defines WDM channel spacing having a multiple of 12.5 GHz. We compare through simulation the performance of two techniques for generating Dual Polarization-Quadrature Amplitude Modulation based on 16 (DP-16QAM), 64 (DP-64QAM) and 128 (DP-128QAM). We first study the performance of WDM-Nyquist and OFDM super-channels implementing DP- 16QAM, DP-64QAM and DP-128QAM in back-to-back scenarios in terms of receiver sensitivity and Optical Signal-to- Noise Ratio (OSNR) requirement with 12.5 GHz flex-grid spacing. We find that DP-16QAM has the best receiver sensitivity and the lower OSNR penalty compared to the other modulation formats in WDM-Nyquist system. With DP- 128QAM sensitivity as reference, we can observe a benefit of 10 dB for DP-16QAM with a BER equal to 3.8 10-3. In addition, we can observe a benefit of 12.4 dB in OSNR for DP-16QAM compared to DP-128QAM for a BER equal to 3.8 10-3. Also, we study the impact of the optical and electrical shaping filters. Finally, we investigate the performance of WDM-Nyquist and OFDM terabit system with 12.5 GHz flex-grid spacing over long-haul dispersion compensated links using Standard Single Mode Fiber (SSMF). We find that DP-16QAM is the suitable modulation format in dispersion compensated WDM-Nyquist systems using SSMF fiber. In addition, we prove that the use of Raman amplification improve the maximum reach of the super-channel by increasing the span distance between the amplifier module. Indeed, using the Raman amplification the maximum reach increase from 812 km to 955 km in a WDM-Nyquist system based on DP-16QAM with 12.5 GHz flex-grid spacing.
The Analysis of Similarity Measure Function in Image Matching Algorithms

Similarity measure function is one of the most important factors influencing the matching precision in the field of computer vision. In this paper, a survey is done on the application frequency of distance similarity measure methods and related similarity measure methods, also the statistic characteristic is been given. The significance of Measure functions variable parameters in image matching is showed. In the real time processing aspect, drawn the conclusion that Manhattan distance measure is the fastest, Euclidean distance take second place, correlation coefficient is worst. However, in the robustness of the noise pollution aspect, correlation coefficient has the strongest robustness, then followed is Manhattan distance, Euclidean distance is worst.
Local structure and structural rigidity of the green phosphor β-SiAlON:Eu2+

Eu2+ inserted in β-Si3−xAlxOxN4−x is a material that shows exceptional promise as a green-emitting phosphor. Synchrotron X-ray and neutron scattering, in conjunction with first-principles calculations and Eu L3 X-ray absorption measurements, yield a consistent picture of the composition, and the favorable position for Eu2+ substitution in the crystal structure. The Debye temperature ΘD, which is a proxy for structural rigidity relating to effectiveness as a phosphor, is very high for the starting β-Si3N4 framework and is determined to decrease only slightly for the small amounts of Al3+ and O2− co-substitution that are required for charge balance associated with Eu2+ insertion.
Tests for Homogeneity of Variances Using Robust Weighted Likelihood Estimates

The classical normal-theory tests for testing the null hypothesis of common variance and the classical estimates of scale have long been known to be quite nonrobust to even mild deviations from normality assumptions for moderate sample sizes. Levene (1960) suggested a one-way ANOVA type statistic as a robust test. Brown and Forsythe (1974) considered a modified version of Levene's test by replacing the sample means with sample medians as estimates of population locations, and their test is computationally the simplest among the three tests recommended by Conover, Johnson, and Johnson (1981) in terms of robustness and power. In this paper a new robust and powerful test for homogeneity of variances is proposed based on a modification of Levene's test using the weighted likelihood estimates (Markatou, Basu, and Lindsay, 1996) of the population means. For two and three populations the proposed test using the Hellinger distance based weighted likelihood estimates is observed to achieve better empirical level and power than Brown-Forsythe's test in symmetric distributions having a thicker tail than the normal, and higher empirical power in skew distributions under the use of F distribution critical values.
Isochrones for Hydrogen-burning Globular Cluster Stars. III. From the Sun to the Globular Clusters

By comparing the available seismic data for the Sun with the properties of various standard solar models, we can check the reliability of the input physics used to produce low-mass stellar models. The best reproduction of the solar interior is obtained when (1) Coulomb corrections are applied to the EOS, (2) microscopic diffusion of He and heavy elements is taken into account, and (3) internal rotation is neglected. This physics is used to derive new models for H-burning low-mass stars (from the zero-age main sequence to the red giant branch tip) and for central He-burning stars (zero-age horizontal branch models). Isochrones for Galactic globular clusters based on these new models are then presented. Note that since the first paper of this series, we have been systematically using an EOS including Coulomb corrections obtained by means of an accurate Monte Carlo method. When microscopic diffusion is also taken into account, we find that: (1) ages inferred from the turnoff luminosity are reduced by about 10%-15%. In particular, the larger the age and the metallicity, the larger the reduction. (2) Microscopic diffusion has a negligible effect on the horizontal-branch luminosity. (3) As a consequence of points (1) and (2), and at variance with previous findings, the ages inferred by adopting the so-called ΔV method depend on diffusion. (4) Finally, ages inferred from Δ(B-V) are strongly reduced (up to 40%-50%).
Siphonic concepts examined: a carbon dioxide gas siphon and siphons in vacuum

Misconceptions of siphon action include assumptions that intermolecular attractions play a key role and that siphons will operate in a vacuum. These are belied by the siphoning of gaseous carbon dioxide and behaviour of siphons under reduced pressure. These procedures are suitable for classroom demonstrations. The principles of siphon action are summarized.
Shock wave driven liquid microjets for drug delivery

A nonintrusive, minimally invasive, needle-less technique to deliver liquids into soft targets is presented. The technique uses a laser-induced shock wave to drive a liquid microjet at a very high speed such that the jet has sufficient momentum to penetrate soft targets. The method can be used to deliver liquid drugs into soft tissues in the human body. The liquid to be delivered is sandwiched between 200 μm thick aluminum foil and a base plate with a perforation of 100 μm diameter. The aluminum foil is ablated using an Nd:YAG laser beam in order to launch a shock wave through it. The shock wave from the foil is transmitted to the sandwiched liquid, which becomes pressurized by the shock propagation and emanates as a microjet through the perforation in the base plate. The microjet thus generated has a steady, average speed of over 200 m/s. The technique has been tested on gelatin models (5% gelatin), in which the jet penetrated to a depth of more than a millimeter.
How to build HAKE Part States Definition : WordNet Expert Annotation Initial Annotations Part States Refinement : Annotators Repetitive Labelling Automatic Check Expert Check Existing Activity Datasets with Instance-level Annotations Automatic Generation

Human activity understanding is crucial for building automatic intelligent system. With the help of deep learning, activity understanding has made huge progress recently. But some challenges such as imbalanced data distribution, action ambiguity, complex visual patterns still remain. To address these and promote the activity understanding, we build a large-scale Human Activity Knowledge Engine (HAKE) based on the human body part states. Upon existing activity datasets, we annotate the part states of all the active persons in all images, thus establish the relationship between instance activity and body part states. Furthermore, we propose a HAKE based part state recognition model with a knowledge extractor named Activity2Vec and a corresponding part state based reasoning network. With HAKE, our method can alleviate the learning difficulty brought by the long-tail data distribution, and bring in interpretability. Now our HAKE has more than 7 M+ part state annotations and is still under construction. We first validate our approach on a part of HAKE in this preliminary paper, where we show 7.2 mAP performance improvement on Human-Object Interaction recognition, and 12.38 mAP improvement on the one-shot subsets.
Absolute deformation potentials and robust ab initio model for band shifts induced by (001) biaxial strain in group IIIA-VA semiconductors

A model for the evolution of conduction and valence bands of IIIA-VA (InAs, GaAs, and InP) semiconductors under (001) biaxial strain is developed. The model is based on the ab initio calculations which take into account finite strain dependent relaxation of the reference levels. The results of ab initio full potential calculations of absolute deformation potentials (ADPs) and (001) biaxial strain-modified band edges are reported. It is shown that in type I heterostructures subjected to (001) compressive biaxial strain, the corrections due to nonzero ADP of the core reference levels reduce the strained band offset for holes.
Mirage is the image of an object in the flat ground surface

It is generally accepted that mirage is formed when temperature of the ground surface, in a flat area like desert, is higher than the temperatures of the over ground air layers. In this case, light emerging from a distant object makes total internal reflection in the air layers and forms the image of the object that is called mirage. Our investigation on mirage formation in desert indicates that there is no meaningful relation between mirage formation and temperature change over the ground. In addition, we show that, the interference of the lights reflected from different air layers destroys the coherency of the image forming light. This happens because the temperature change occurs in an interval larger than a wavelength. In the second part of the report we demonstrate theoretically and experimentally that flat rough surfaces behave like mirrors at very large incident angles. We show that there is a threshold incident angle for observation of image in a rough surface that depends on the surface roughness and light wavelength. The shortest distance between observer and the image is determined by the threshold incident angle. Mirage is such an image. Image formation is studied in rough sheet glass surfaces that prepared by grinding with powders of different sizes.
A Tutorial on the SWEEP Operator

Abstract The importance of the SWEEP operator in statistical computing is not so much that it is an inversion technique, but rather that it is a conceptual tool for understanding the least squares process. The SWEEP operator can be programmed to produce generalized inverses and create, as by-products, such items as the Forward Doolittle matrix, the Cholesky decomposition matrix, the Hermite canonical form matrix, the determinant of the original matrix, Type I sums of squares, the error sum of squares, a solution to the normal equations, and the general form of estimable functions. First, this tutorial describes the use of Gauss-Jordan elimination for least squares and continues with a description of a completely generalized sweep operator that computes and stores (X′X)−, (X′X)− X′X, (X′X)− X′Y, and Y′Y — Y′X(X′X)− X′Y, all in the space of a single upper triangular matrix.
Unbiased support vector classifiers

Support Vector Classifiers (SVC) are claimed to provide a natural mechanism for implementing Structural Risk Minimization (SRM), obtaining machines with good generalization capabilities. SVC leads to the optimal hyperplane (maximal margin) criterion for separable datasets but, in the nonseparable case, a functional with an additional term has to be minimized. The particular form of this extra term is such that the minimization can be solved via Quadratic Programming (QP), but, in this case, it represents a rather coarse approximation to the number of errors. We propose an unbiased implementation of SVC by introducing a more appropriate "error counting" term. This way, the number of classification errors is truly minimized (hence the "unbiased" appellative), while the maximal margin solution is obtained in the separable case. QP can no longer be used for solving the new minimization problem, and we apply instead an iterated Weighted Least Squares (WLS) procedure. Computer experiments show that the proposed method is superior to the classical approach in terms of both classification error and machine complexity.
An arbitrary strains carbon nanotube composite piezoresistivity model for finite element integration

Piezoresistive carbon nanotube (CNT) composites can radically enhance structural identification and health monitoring through continuous self-sensing. However, prevailing piezoresistivity models examine only uniaxial strain and are too computationally burdensome to be implemented on a structural scale. This research circumvents these limitations by developing an analytical piezoresistivity model for CNT composites that is adaptable to the finite element formulation enabling the analysis of complicated structures subjected to arbitrary strain. The accuracy of the model is verified by comparison to uniaxial piezoresistivity experiments in existing literature.
The Evolution and Complexity of Urban Street Networks

Street networks are one of the very few types of complex networks where the history of the network can be traced over long periods of time. Here we introduce methods for quantifying the geometric characteristics of street networks and analyze the details of the evolution of the networks of Sheffield (UK), Khorramabad (Iran), and Kerman (Iran) over tens to hundreds of years. The results suggest that the spatial distribution of streets, in particular their lengths and orientations and associated entropies, are strongly affected by the surrounding landscapes but in different ways. The length entropies are mostly controlled by the space available for network growth, whereas the orientation entropies are mostly controlled by the shapes of the constraining landscape features. Thus, the network of Khorramabad, located in a narrow crescent-shaped valley, shows the smallest increase in length entropy (space constraints) and the largest in orientation entropy (shape constraints) over time. By contrast, the network of Kerman, in a flat desert area with essentially no space or shape constraints, has the largest increase in length entropy and the smallest increase in orientation entropy over time. The network of Sheffield, a city subject to moderate landscape constraints of hills and valleys, has length and orientation entropies that fall between these extremes.
Preconditioning operators for grid parabolic problems

The paper deals with studying some preconditioning operators which provide uncoditional convergence of difference schemes for solving parabolic problems. Three examples of such operators are considered. These are a preconditioner of the domain decomposition method of the Neumann-Dirichlet type and two preconditioners of the fictitious domain methods for the Neumann and the Dirichlet boundary value problems, respectively.
Stochastic Theta Method for a Reflected Stochastic Differential Equation

In this article, a stochastic theta method for a reflected stochastic differential equation is proposed. When the parameter θ = 0, this method coincides with the projection Euler scheme; while when the parameter θ = 1, it is called an implicit projection Euler scheme which is first proposed in this article. Under some conditions, the strong convergence and the A-stability of this numerical scheme are proved.
High Spatial Resolution Near-Infrared Images of Taurus Protostars

We analyze near-infrared K- and L-band images of six embedded Class I objects in the Taurus-Auriga molecular cloud. Three of these sources were observed in both bands and three were observed only at L. The L- and K-band images were obtained with the Cryogenic Optical Bench at the KPNO 4 m telescope in the diffraction-limited mode. With the high spatial resolution L-band data, we identify IRAS 04239+2436 as a close pair with a projected separation of 0.29″. We use a radiative transfer code to model the images and derive physical and geometrical parameters for each source. Because the projected positions of the six analyzed sources on the cloud coincide with the densest zones in the complex (AV ∼ 10-30 mag), we use two models for the optical properties of dust grains in the envelopes: a diffuse ISM model and a grain model with ratio of total to selective extinction RV = 4.3 corresponding to the measured R values in the densest regions of the Taurus molecular cloud. Although the two grain models have different opacities, we can match the observed images with either model by selecting the appropriate envelope infall rate. Thus we cannot distinguish between the two grain models over this narrow wavelength range (K and L bands).
Electron mobility enhancement in nanoscale silicon-on-insulator diffusion layers with high doping concentration of greater than 1 1018 × cm-3 and silicon-on-insulator thickness of less than 10 nm

Electron mobility in nanoscale silicon-on-insulator (SOI) layers with a doping concentration ranging from 2 × 1017 cm−3 to 1 × 1019 cm−3 is thoroughly studied. We observe that electron mobility in highly doped nanoscale extremely thin SOI (ETSOI) layers with thicknesses ranging from 5 to 11 nm is greater than electron mobility in bulk Si with the same doping concentration. Since no dopant ion exists in the oxides above and below ETSOI, the absence of ions close to the ETSOI layers effectively reduces the number of Coulomb centers that scatter carriers in the ETSOI layers. We show that the ratio of SOI thickness to the average distance between donor ions is critically important to understand the mobility enhancement in nanoscale ETSOI. It is demonstrated that mobility enhancement can be universally described as a function of the ratio described above. The findings of our study are indispensable in designing aggressively scaled SOI metal-oxide-semiconductor field-effect transistors.
Channel estimation for asymmetrically clipped optical orthogonal frequency division multiplexing communication system

Abstract. The channel estimation problem for asymmetrically clipped optical orthogonal frequency division multiplexing wireless communication systems is investigated. In order to resolve the noise-sensitive problem of traditional least squares-based channel estimation method, a new channel estimation method which is based on superimposed training sequence and guarantees the linear minimum mean square error estimate is proposed. Cycle training sequence is added at variable power ratio to the information sequence at the transmitter prior to transmission. Then, statistical average method is employed to separate training and information sequences at the receiver. Simulation results show that the power ratio of training sequence needs to balance between the mean square error (MSE) of estimation and the error bit rate. Moreover, compared with the traditional least squares-based method, the proposed method has significantly improved the estimation performance under the condition of low signal-to-noise ratio, especially, when the MSE of the estimation reduces 1 to 2 orders.
Surface ejection in single crystal sputtering

Surface atom ejection, an essential component of single crystal sputtering phenomena, is investigated for a realistic surface model using computer simulation. The dynamics of ejection are analyzed in terms of the collective attractive field of the surface and binary repulsive collisions of the ejected atom with its neighbors in the surface. In-surface correlated collision sequences initiated by ejection are also discussed in detail. It is found that ejection from the surface layer is a fundamentally anisotropic process exhibiting a complex range of interaction types.
Robust Dissipative Filtering for Polytopic Uncertain Singular Systems in Continuous & Discrete Time

This paper considers the problem of continuous and discrete time dissipative filter design method for the -singular systems with polytopic uncertainties. Two bounded real lemmas (BRL) for the robust filters of dissipative singular systems along with the polytopic uncertainties are proposed on the basis of Lyapunov criterion. The sufficient conditions for both continuous and discrete time dissipative filter design methods are derived using the obtained BRL by linear matrix inequality (LMI) approach. Finally, the validities of the proposed methods are shown by numerical examples.