Miracle-dz/UniFAR-FTUs huggingface dataset:
Transmission electron microscopy investigation of the morphology of InP Stranski–Krastanow islands grown by metalorganic chemical vapor deposition

We have used transmission electron microscopy to determine the morphology of InP Stranski–Krastanow islands in GaInP, grown by metalorganic chemical vapor deposition at 580 °C. We investigated both capped and uncapped islands. It was found that the fully developed islands have the principal shape of truncated pyramids with a hexagonal base both before and after overgrowth. The planes defining the islands are of {001}, {110}, and {111} types. The base dimensions are 40–50 nm and 55–65 nm in the [110] and [110] directions, respectively, and the height is 12–18 nm.
Transitions in P II

We present extensive configuration interaction calculations of probabilities of electric dipole transitions between all J-levels of 3s23p2, 3s23p4p, 3s3p3, 3s23p4s and 3s23p3d states in P II, from which lifetimes of these levels are determined. A number of reassignments of configuration labels are suggested. In particular, the 3s3p3 1D2 configuration does not dominate any state, being instead smeared out over the Rydberg series.
A nonlinear critical layer generated by the interaction of free Rossby waves

Two free waves propagating in a parallel shear flow generate a critical layer when their nonlinear interaction induces a perturbation whose phase velocity matches the basic-state velocity somewhere in the flow domain. The condition necessary for this to occur may be interpreted as a resonance condition for a triad formed by the two waves and a (singular) mode of the continuous spectrum associated with the shear. The formation of the critical layer is investigated in the case of freely propagating Rossby waves in a two-dimensional inviscid flow in a β-channel. A weakly nonlinear analysis based on a normal-mode expansion in terms of Rossby waves and modes of the continuous spectrum is developed; it leads to a system of amplitude equations describing the evolution of the two Rossby waves and of the modes of the continuous spectrum excited during the interaction. The assumption of weak nonlinearity is not however self-consistent: it breaks down because nonlinearity always becomes strong within the critical layer, however small the initial amplitudes of the Rossby waves. This demonstrates the relevance of nonlinear critical layers to monotonic, stable, unforced shear flows which sustain wave propagation. A nonlinear critical-layer theory is developed that is analogous to the well-known theory for forced critical layers. Differences arise because of the presence of the Rossby waves: the vorticity in the critical layer is advected in the cross-stream direction by the oscillatory velocity field due to the Rossby waves. An equation is derived which governs the modification of the Rossby waves that results from their interaction; it indicates that the two Rossby waves are undisturbed at leading order. An analogue of the Stewartson–Warn–Warn analytical solution is also considered.
Extensions of Heterogeneity in Integration and Prediction (HIP) with R Shiny Application

Multiple data views measured on the same set of participants is becoming more common and has the potential to deepen our understanding of many complex diseases by analyzing these different views simultaneously. Equally important, many of these complex diseases show evidence of subgroup heterogeneity (e.g., by sex or race). HIP (Heterogeneity in Integration and Prediction) is among the first methods proposed to integrate multiple data views while also accounting for subgroup heterogeneity to identify common and subgroup-specific markers of a particular disease. However, HIP is applicable to continuous outcomes and requires programming expertise by the user. Here we propose extensions to HIP that accommodate multi-class, Poisson, and Zero-Inflated Poisson outcomes while retaining the benefits of HIP. Additionally, we introduce an R Shiny application, accessible on shinyapps.io at https://multi-viewlearn.shinyapps.io/HIP_ShinyApp/, that provides an interface with the Python implementation of HIP to allow more researchers to use the method anywhere and on any device. We applied HIP to identify genes and proteins common and specific to males and females that are associated with exacerbation frequency. Although some of the identified genes and proteins show evidence of a relationship with chronic obstructive pulmonary disease (COPD) in existing literature, others may be candidates for future research investigating their relationship with COPD. We demonstrate the use of the Shiny application with a publicly available data. An R-package for HIP would be made available at https://github.com/lasandrall/HIP.
Galois invariants for S-units

Let K / k be a finite Galois extension of number fields with Galois group G and let S be a finite G -stable set of primes of K , containing all primes which are archimedean or ramified over k and which generates the ideal class group. By Theorem B, the G -module E of S -units of K is determined, up to stable isomorphism, by (a) the [inline-graphic xmlns:xlink="http://www.w3. org/1999/xlink" xlink:href="01i" /] G -lattice Δ S , which is the kernel of the augmentation [inline-graphic xmlns:xlink="http://www.w3. org/1999/xlink" xlink:href="02i" /] S → [inline-graphic xmlns:xlink="http://www.w3. org/1999/xlink" xlink:href="03i" /], (b) the G -module μ of roots of unity in K , (c) a distinguished character e of H 2 ( G , Hom (Δ S , μ)), and (d) the Chinburg class Ω m ( K / k ) in the locally free class group of [inline-graphic xmlns:xlink="http://www.w3. org/1999/xlink" xlink:href="04i" /] G . Our method is a study of the homotopy properties of Tate sequences of K / k , hence it is essential that our Galois invariants be specified without prior knowledge of these sequences. This is clear for (a) and (b), while for (c) it follows from Theorem A, which expresses e in terms of the local and global invariant maps of class field theory. And for (d), it would follow from Chinburg's conjecture that Ω m is the root number class of K / k .
An EXOSAT observation of quiescent and flare coronal X-ray emission from Algol

L'emission RX du systeme Algol a son origine dans la couronne associee a l'etoile K. Le satellite EXOSAT a observe le systeme durant 35 h en continu centrees sur l'occultation de l'etoile K par la primaire B, afin d'etudier la structure spatiale de la couronne
Application of Signal-Processing Techniques To Dipole Excitations in the Finite-Difference Time-Domain Method

The applications of discrete-time signal-processing techniques, such as windowing and filtering for the purpose of implementing accurate excitation schemes in the finite-difference time-domain (FDTD) method are demonstrated. The effects of smoothing windows of various lengths and digital lowpass filters of various bandwidths and characteristics are investigated on finite-source excitations of the FDTD computational domain. Both single-frequency sinusoidal signals and multifrequency arbitrary signals are considered.
Aggregation and Ecological Effects in Geographically Based Data

Statistics calculated using the means of geographic areas can differ substantially from the corresponding statistics based on data from individuals. Analysts who base their conclusions about individual-level relationships on area-level analyses run the risk of committing the ecological fallacy. Statistical models are proposed that capture the essential features of the structure of a population composed of geographically defined groups and can encompass grouping processes and contextual effects. These models are used to show how small effects in the analysis of individual-level data can be magnified substantially when the corresponding analysis based on aggregated data is carried out. Thus the source of aggregation effects is exposed. While aggregation effects have been studied by many authors, no general approach has been offered to the problem of adjusting an area-level analysis so as to correct for aggregation effects and hence remove, or at least reduce, the bias that leads to the ecological fallacy. The statistical models proposed are used to provide an approach to this problem. Data from the 1991 U.K. Census of Housing and Population are used to illustrate the size of the aggregation effects and the extent to which the proposed adjustments succeed in their objective.
Microstructure and properties of Cu-doped ZnO films prepared by dc reactive magnetron sputtering

ZnO film is promising for high frequency surface acoustic wave device application when coupled with diamond. In order to get good performance and reduce insertion loss of the device, which demand a piezoelectric material possessing high electrical resistivity and piezoelectric constant d33, Cu-doped ZnO films have been prepared by direct current reactive magnetron sputtering using a zinc target with various Cu-chips attached. The influences of a Cu-doping condition on the microstructure and properties of ZnO films are investigated by x-ray diffraction, x-ray photoelectron spectroscopy, a four-point probe resistivity test system and the periodic compressional force method. The experimental results indicate that high resistivity (9 × 108 Ω cm) and piezoelectric constant (d33 = 13.5 pC N−1) ZnO films with perfect c-axis orientation and fine grain polycrystalline can be achieved by 2.0 at% Cu-doping. The contribution of the Cu-doping to the electrical resistivity and piezoelectric constant d33 is discussed.
Traffic Sign Recognition Utilizing an Eigen Space Method Based on the KL Transform

This study explains that a method utilizing the eigen spaces obtained by the KL transform for automatic recognition by camera of the speed on a speed limit sign has the following advantages: it is robust in response to changes in intensity patterns caused by the direction the sign is facing and by the amount of light striking the sign, and it is able to reduce the recognition processing time by reducing the number of feature vector dimensions during analysis. The method for recognition of traffic signs previously proposed by the authors of this study was a method for recognition based on extracting geometric shapes from the sign and recognizing them based on their aspect ratios. As such, this method was not able to identify the numbers on a speed limit sign, all of which have identical aspect ratios. It will be shown that the method in this study is able to recognize nearly all speed limits indicated on traffic signs within several 100s of ms after image acquisition. This method was applied to still images and its effectiveness was verified from the perspective of the following requirements for providing accurate information concerning the vehicle surroundings to the driver: high processing speed, high recognition accuracy, detection of all detectable objects without omission, and robustness in response to changes in the surrounding environment.
SURVIVAL OF AMORPHOUS WATER ICE ON CENTAURS

Centaurs are believed to be Kuiper Belt objects in transition between Jupiter and Neptune before possibly becoming Jupiter family comets. Some indirect observational evidence is consistent with the presence of amorphous water ice in Centaurs. Some of them also display a cometary activity, probably triggered by the crystallization of the amorphous water ice, as suggested by Jewitt and this work. Indeed, we investigate the survival of amorphous water ice against crystallization, using a fully three-dimensional thermal evolution model. Simulations are performed for varying heliocentric distances and obliquities. They suggest that crystallization can be triggered as far as 16 AU, though amorphous ice can survive beyond 10 AU. The phase transition is an efficient source of outgassing up to 10–12 AU, which is broadly consistent with the observations of the active Centaurs. The most extreme case is 167P/CINEOS, which barely crystallizes in our simulations. However, amorphous ice can be preserved inside Centaurs in many heliocentric distance–obliquity combinations, below a ∼5–10 m crystallized crust. We also find that outgassing due to crystallization cannot be sustained for a time longer than 104–104 years, leading to the hypothesis that active Centaurs might have recently suffered from orbital changes. This could be supported by both observations (although limited) and dynamical studies.
Effects of Dye on Formation and Properties of Light-Induced Self-Written Waveguide

The effects of rhodamine 6G dye on the formation and properties of a light-induced self-written waveguide (LISW) were demonstrated. We dispersed the 0.01 wt% dye in a conventional UV-curable resin and formed the LISW using a green laser. The excessive laser irradiation, which decomposed the dye, induced the solid cladding of the LISW at a wavelength which was shorter than the optical absorption peak. Thus, the dye was used not only as a sensitizer but also as the dominant factor for controlling the refractive index difference between the core and the solid cladding of the all-solid LISW.
Aerodynamic Focusing of Microparticles in Gas Flows With Shock Waves

The effect of aerodynamic focusing of microparticles in gas-particle flows is employed mainly for creating collimated particle beams. These beams are used in various technical applications, such as coating, “direct-write”, surface processing technologies, needle-free injections, etc. In this study, we propose and investigate two new flow schemes in which the effect of aerodynamic focusing of small low-inertia particles may be realized in high-speed gas flows with shock waves. The first one is a steady-state dusty-gas flow behind the point of interaction of two crossing shock waves. The convergence of the carrier-phase streamlines and the presence of particle inertia result in the formation of a high-concentration particle beam behind the shock interaction point. In the second flow scheme considered, the particle focusing effect is attributable to the action of the Saffman lateral force, exerting on the particles in boundary layers behind a shock wave travelling in a narrow channel with a constant cross-section. In both cases, the ranges of governing parameters are found for which the focusing is “optimal”, i.e. a very thin collimated beam of microparticles is formed.Copyright © 2013 by ASME
EFFICIENCY AND ACCURACY OF HIGHER-ORDER BOUNDARY-ELEMENT METHODS FOR STEADY CONVECTIVE HEAT DIFFUSION

Higher-order boundary-element methods (BEM) are presented for steady-state convective diffusion problems in two dimensions. The free-space steady convective diffusion fundamental solutions considered in this article provide an analytical upwinding for the entire Peclet number range, from zero to infinity. However, integration of the kernels over the boundary elements requires considerable attention, especially at higher Peclet numbers. We define an influence domain due to these convective kernels and then localize the surface integrations only within the domain of influence. The localization of the kernels becomes more prominent as the Peclet number of the flow increases. This, in turn, leads to increasing sparsity and improved conditioning of the global matrix. Consequently, iterative solvers become the primary choice. We consider an example problem with an exact solution, and investigate the accuracy and efficiency of the higher-order BEM formulations for Peclet numbers in the range from 200 to 200,000. The quartic boundary elements included in this study are shown to be extremely efficient.
PSF and MTF measurement methods for thick CCD sensor characterization

Knowledge of the point spread function (PSF) of the sensors to be used in the Large Synoptic Survey Telescope (LSST) camera is essential for optimal extraction of subtle galaxy shape distortions caused by gravitational weak lensing. We have developed a number of techniques for measuring the PSF of candidate CCD sensors to be used in the LSST camera, each with its own strengths and weaknesses. The two main optical PSF measurement techniques that we use are the direct Virtual Knife Edge (VKE) scan as developed by Karcher, et al.1 and the indirect interference fringe method after Andersen and Sorensen2 that measures the modulation transfer function (MTF) directly. The PSF is derived from the MTF by Fourier transform. Other non-optical PSF measurement techniques that we employ include 55Fe x-ray cluster image size measurements and statistical distribution analysis, and cosmic ray muon track size measurements, but are not addressed here. The VKE technique utilizes a diffraction-limited spot produced by a Point-Projection Microscope (PPM) that is scanned across the sensor with sub-pixel resolution. This technique closely simulates the actual operating condition of the sensor in the telescope with the source spot size having an f/# close to the actual telescope design value. The interference fringe method uses a simple equal-optical-path Michelson-type interferometer with a single-mode fiber source that produces interference fringes with 100% contrast over a wide spatial frequency range sufficient to measure the MTF of the sensor directly. The merits of each measurement technique and results from the various measurement techniques on prototype LSST sensors are presented and compared.
Design and fabrication of planar multilayer structures with coherent thermal emission characteristics

A large number of recent publications dealt with enhanced emission properties of micro/nanostructures by the excitation of surface plasmon or phonon polaritons. Some used grating structures to demonstrate coherent thermal emission in a narrow spectral band and towards a well-defined direction. Others suggested that planar layers could also be used to achieve coherent emission. In the present paper, we describe two alternative designs with fewer layers for the application as coherent emission sources in planar multilayer structures. One design is a composite of several unit cells of one-dimensional photonic crystal atop a highly reflective material. Coherent emission can be obtained by the excitation of surface waves between the photonic crystal and the reflector. The other design employs a Fabry-Perot resonance cavity constructed by coating a dielectric layer onto the reflector and then a thin metallic film on the dielectric layer. When standing waves exist in the cavity, the emissivity plots show sharp s.
Optimal insurance demand under marked point processes shocks

We study the stochastic control problem of maximizing expected util- ity from terminal wealth, when the wealth process is subject to shocks produced by a general marked point process; the problem of the agent is to derive the optimal allocation of his wealth between investments in a nonrisky asset and in a (costly) insurance strategy which allows “lower- ing” the level of the shocks. The agent’s optimization problem is related to a suitable dual stochastic control problem in which the constraint on the insurance strategy disappears. We establish a general existence result for the dual problem as well as the duality between both problems. We conclude by some applications in the context of power (and logarithmic) utility functions and linear insurance premium which show, in particular, the existence of two critical values for the insurance premium: below the lower critical value, agents prefer to be completely insured, whereas above the upper critical value they take no insurance.
An Investigation of Fibonacci-like Sequences in Biology and Mathematics

There are many generalizations of the Fibonacci sequence such as the tribonacci, tetranacci, etc. A recent interesting generalization is the random analogue of the Fibonacci sequence defined by the random Fibonacci recurrence vn = ±vn_i ± vn_2, where Vi = 1, v2 = 1, and each ± sign is independent and either + or with probability 1/2. Viswanath shows that the absolute value of the n-th root of vn approaches C=l. 1319882 as η tends to infinity. The constant C can be considered as the random analogue of the Golden ratio φ, which is the growth rate of the Fibonacci sequence. Although φ shows up frequently in mathematics and nature, the growth rates of the other deterministic Fibonacci and the random Fibonacci sequences have not shown up as frequently. This observation prompted the investigation to see if the other constants can be found in nature or other systems. In this paper the presence of the generalized Fibonacci sequences and their related constants are shown in the geometry of the DNA, in the number of chromosomes in some animals and plants and in the measurements of the Arabian camel. An application of the random Fibonacci sequence in random integer generation is also briefly mentioned.
Stable axisymmetric SPH formulation with no axis singularity

The axisymmetric formulation of the governing equations for geomechanics in the framework of smoothed particle hydrodynamics (SPH) is presented in this study. Two forms of SPH discretization for the motion equations, which are labeled as form I and form II, are proposed, and the methods to compute the hoop stress and strain terms including hoop strain rate and the acceleration introduced by the hoop stress are compared. To avoid possible singularity problem near the axis of symmetry, a perfectly smooth contact along with ghost particles are applied to prevent the real particles from overly approaching the axis of symmetry to remove this potential singularity. In addition, the Mohr–Coulomb constitutive model is implemented into the SPH formulation in describing soil behavior. Four numerical tests are carried out to validate and compare the accuracy and stability of the proposed algorithms, and their results are compared with analytical solutions and results from FEM analysis. The performance in these comparisons suggests that SPH II with hoop terms computed through direct hoop method is more stable than the others, and the adoption of contact for the symmetric axis is efficient in eliminating the singularity problem. Copyright © 2015 John Wiley & Sons, Ltd.
CHIP: Contrastive Hierarchical Image Pretraining

Few-shot object classification is the task of classifying objects in an image with limited number of examples as supervision. We propose a one-shot/few-shot classification model that can classify an object of any unseen class into a relatively general category in an hierarchically based classification. Our model uses a three-level hierarchical contrastive loss based ResNet152 classifier for classifying an object based on its features extracted from Image embedding, not used during the training phase. For our experimentation, we have used a subset of the ImageNet (ILSVRC-12) dataset that contains only the animal classes for training our model and created our own dataset of unseen classes for evaluating our trained model. Our model provides satisfactory results in classifying the unknown objects into a generic category which has been later discussed in greater detail.