Miracle-dz/UniFAR-FTUs huggingface dataset:
The correlation between solar and geomagnetic activity - Part 1: Two-term decomposition of geomagnetic activity

Abstract. By analyzing the logarithmic relationship between geomagnetic activity as represented by the annual aa index and solar magnetic field activity as represented by the annual sunspot number (Rz) during the period 1844–2010, aa is shown to lie in between two lines defined solely by Rz. Two ways can be used to decompose the aa index into two components. One is decomposing aa into the sum of the baseline (aab) and the remainder (aau) with a null correlation. Another is dividing the top-line (aat) into the sum of aa and the remainder (aad) with a null correlation. The first decomposition is similar to the traditional one. The second decomposition implies a nonlinear relationship of aa with Rz (aat) and a decay process (aad). Therefore, aat=aa+aad=aab+aau+aad: (i) aat is related to the solar energy potential of generating geomagnetic activity (associated with Rz); (ii) aab is related to transient phenomena; (iii) aau is related to recurrent phenomena; and (iv) aad is related to the energy loss in the transmission from solar surface to the magnetosphere and ionosphere that failed to generate geomagnetic activity.
Lemmes de moyenne et Transformée aux rayons X Averaging Lemmas and the X-ray transform

We introduce a new method to prove averaging lemmas, i.e. prove a regularizing effect on the average in velocity of a solution to a kinetic equation. The method does not require the use of Fourier transform and the whole procedure is performed in the ’real space’; It leads to estimating an operator very similar to the so-called X-ray transform. We are then able to improve the known results when the integrability in space and velocity is different. Résumé. Nous introduisons une nouvelle méthode pour obtenir des lemmes de moyennes, c’est-à-dire prouver un effet régularisant pour les moyennes en vitesse d’une équation cinétique. Cette méthode ne fait pas appel à la transformée de Fourier et toute la preuve se fait dans “l’espace réel” ; on est alors ∗partially supported by the projects PICS 1014 and HPRN-CT-2002-00282
Simulation of high‐frequency solar wind power spectra using Hall magnetohydrodynamics

Solar wind frequency spectra show a distinct steepening of the ƒ−5/3 power law inertial range spectrum at frequencies above the Doppler-shifted ion cyclotron frequency. This is commonly attributed to dissipation due to wave-particle interactions. We consider the extent to which this steepening can be described, using a magnetohydrodynamic formulation that includes the Hall term. An important characteristic of Hall MHD is that although the ion cyclotron resonance is included, there is no wave-particle dissipation of energy. In this study we use a compressible Hall MHD code with a constant magnetic field and a polytropic equation of state. Artificial dissipation in the form of a bi-Laplacian operator is used to suppress numerical instabilities, allowing for a clear separation of the dissipative scales from the ion cyclotron scales. A distinct steepening appears in the simulation power spectra near the cyclotron resonance for certain types of initial conditions. This steepening is associated with the appearance of right circularly polarized fluctuations at frequencies above the ion cyclotron resonance. Similar steepenings and polarization enhancements are observed in solar wind magnetic field data.
UNIQUENESS OF GENERALIZED WALDSPURGER MODEL FOR GL(2n)

Let E/F be a quadratic extension of non-archimedean local field and let G be an inner form of GL(2n, F ) over F , which contains a subgroup H isomorphic to GL(n,E). In this paper we prove that (G,H) is a Gelfand pair, i.e., the H-invariant linear functional, if there exists one, on the space of an irreducible admissible representation of G is unique up to a scalar. Globally this result will play an important role in the study of H-period integrals of cusp forms on G, and its relations to the special values of automorphic L-functions.
Quantized Frame Expansions with Erasures

Abstract Frames have been used to capture significant signal characteristics, provide numerical stability of reconstruction, and enhance resilience to additive noise. This paper places frames in a new setting, where some of the elements are deleted. Since proper subsets of frames are sometimes themselves frames, a quantized frame expansion can be a useful representation even when some transform coefficients are lost in transmission. This yields robustness to losses in packet networks such as the Internet. With a simple model for quantization error, it is shown that a normalized frame minimizes mean-squared error if and only if it is tight. With one coefficient erased, a tight frame is again optimal among normalized frames, both in average and worst-case scenarios. For more erasures, a general analysis indicates some optimal designs. Being left with a tight frame after erasures minimizes distortion, but considering also the transmission rate and possible erasure events complicates optimizations greatly.
Self-affine tiles in ℝn

Abstract A self-affine tile in R n is a set T of positive measure with A ( T )=∪ d ∈ D ( T + d ), where A is an expanding n × n real matrix with |det( A )|= m an integer, and D ={ d , d 2 , . , d m }⊆ R n is a set of m digits. It is known that self-affine tiles always give tilings of R n by translation. This paper extends known characterizations of digit sets D yielding self-affine tiles. It proves several results about the structure of tilings of R n possible using such tiles, and gives examples showing the possible relations between self-replicating tilings and general tilings, which clarify results of Kenyon on self-replicating tilings.
Constraints on the abstraction of solutions

Students in college algebra classes attempted to solve a series of three mixture problems and three distance problems and to match concepts between the first two problems in a series. The detailed comparison of two isomorphs did not result in the abstraction of a solution schema, as it was found to do by Gick and Holyoak (1983) for convergence problems. Attempts to promote abstraction by not allowing students to refer to a specific analogue (Experiment 2) and by providing information about corresponding concepts and principles (Experiment 3) were unsuccessful. These findings suggest that the bottom-up, similarity-based approaches encouraged by mapping concepts may need to be supplemented by top-down, principle-driven instruction
Surfaces with parallel mean curvature vector

Let M be a surface immersed in a Riemannian manifold JR of dimension m. Let D denote the covariant differentiation of R and n be a normal vector field on M. If we denote by D*n the normal component of Dn9 then D* defines a connection in the normal bundle. A normal vector field n is called parallel if D*n = 0. Let H and h denote the mean curvature vector and the second fundamental form of M in E. It is easy to see that minimal surfaces of a euclidean m-space ET and minimal surfaces of hyperspheres of ET are surfaces of ET with parallel mean curvature vector, i.e. D * H = 0. On the other hand, for any analytic function q> # 0 of z = u + iv9 defined in a neighborhood of the origin in the (M, t;)-plane, and constants a, /? with a > 0, Hoffman [3], [4] proved that, up to euclidean motions and isothermal coordinate E(u9v\ locally there exists one and only one surface in F \ denoted by M(q>9 a, j8), with parallel mean curvature vector H such that a = \H\9 and 9 a, /? )? The main purpose of this paper is to announce the following results. The details will appear elsewhere.
Sensitivity analysis of the climate of a chaotic ocean circulation model

We explore sensitivity analyses of ocean circulation models by comparing the adjoint and direct‐perturbation methods. We study the sensitivity of time‐averaged inter‐gyre vorticity transport to the imposed wind‐stress curl in an eddy‐permitting reduced‐gravity ocean model of a double gyre. Two regimes exist: a non‐chaotic regime for low wind‐stress curl, and a chaotic regime for stronger wind forcing. Direct‐perturbation methods are found to converge, with increasing integration time, to a stable ‘climate’ sensitivity in both the chaotic and non‐chaotic regimes. The adjoint method converges in the non‐chaotic regime but diverges in the chaotic regime. The divergence of adjoint sensitivity in the chaotic regime is directly related to the chaotic divergence of solution trajectories through phase‐space. Thus, standard adjoint sensitivity methods cannot be used to estimate climate sensitivity in chaotic ocean circulation models. An alternative method using an ensemble of adjoint calculations is explored. This is found to give estimates of the climate sensitivity of the time‐mean vorticity transport with O(25%) error or less for integration times ranging from one month to one year. The ensemble‐adjoint method is particularly useful when one wishes to produce a map of sensitivities (for example, the sensitivity of the advective vorticity transport to wind stress at every point in the domain) as direct sensitivity calculations for each point in the map are avoided. However, an ensemble‐adjoint of the variance of the vorticity transport to wind‐stress curl fails to estimate the climate sensitivity. We conclude that the most reliable method of determining the climate sensitivity is the direct‐perturbation method, but ensemble‐adjoint techniques may be of use in some problems. Copyright © 2002 Royal Meteorological Society.
Homotopy perturbation method for numerical solutions of coupled Burgers equations with time‐ and space‐fractional derivatives

Purpose – This paper aims to directly extend the homotopy perturbation method to study the coupled Burgers equations with time‐ and space‐fractional derivatives.Design/methodology/approach – The realistic numerical solutions were obtained in a form of rapidly convergent series with easily computable components.Findings – The figures show the effectiveness and good accuracy of the proposed method.Originality/value – The paper obtains realistic numerical solutions in a form of rapidly convergent series with easily computable components. It shows the effectiveness and good accuracy of the proposed method.
An Assessment of the Impact of Antishattering Tips and Artifact Removal Techniques on Cloud Ice Size Distributions Measured by the 2D Cloud Probe

AbstractPrior estimates of ice crystal size distributions derived from 2D cloud probes (2DCs) have been artificially amplified by small ice crystals generated from the shattering of large ice crystals on the probe tips. Although antishatter tips and algorithms exist, there is considerable uncertainty in their effectiveness. This paper examines differences in ice crystal size distributions from adjacent 2DCs with standard and antishatter tips, and processed with and without antishattering algorithms. The measurements were obtained from the National Research Council of Canada Convair-580 during the 2008 Indirect and Semi-Direct Aerosol Campaign (ISDAC) and the National Center for Atmospheric Research C-130 during the 2011 Instrumentation Development and Education in Airborne Science (IDEAS-2011). The 2DC size distributions are compared with those from the Holographic Detector for Clouds (HOLODEC), which has antishatter tips and allows for identification of shattering through spatial statistics.The ratio of .
Spiral growth of GaSb on (001) GaAs using molecular beam epitaxy

Atomic force microscopy is employed to obtain images of the surface of GaSb epilayers grown on (001) GaAs using molecular beam epitaxy. The images reveal a surface that consists of micron size mounds that are approximately 4 nm high. A stepped surface is clearly observed on the mounds with a single step edge that originates from a screw dislocation at the center of the mound and moves out to the edge in a spiral fashion. The surface structure of the spiral mounds is observed to depend on the growth temperature of the GaSb epilayer, presumably as a result of a shorter diffusion length of the group III adatoms for lower substrate temperatures.
Optimal carry save networks

A general theory is developed for constructing the asymptotically shallowest networks and the asymptotically smallest networks (with respect to formula size) for the carry save addition of n numbers using any given basic carry save adder as a building block. Using the optimal carry save additional networks the shallowest known multiplication circuits and the shortest formulae for the majority function (and many other symmetric Boolean functions) are obtained. In this paper simple basic carry save adders are described using which multiplication circuits of depth 3.71 log n (the result of which is given as the sum of two numbers) and majority formulae of size O (n3.13) are constructed. Using more complicated basic carry save adders, not described here, these results could be further improved. Our best bounds are currently 3.57 log n for depth and O (n3.13) for formula size.
A simple semi‐Lagrangian scheme for advection equations

A semi-Lagrangian scheme is proposed by using forward trajectories and a splitting approach to the interpolation procedure. Several polynomial interpolation schemes are tested, including cubic spline and Lagrange polynomials of degree 3, 5 and 7. A simple filter is also proposed to eliminate spurious short waves and to achieve positive-definiteness. Uniform, rotational and Smolarkiewicz's deformational flows are tested, a solution to the inviscid Burger's equation is also provided. This new algorithm employing cubic-spline interpolation and the new filter yields efficient and accurate short-term simulations. The advantage in efficiency of adopting split trajectories for interpolation is accompanied by a restriction which is slightly more stringent than the stability criterion for conventional semi-Lagrangian advection schemes. It is also found that the simple filter can eliminate spurious short waves very effectively without degrading the solutions.
Size-induced lattice relaxation in CeO 2 nanoparticles

Size-induced lattice relaxation was observed for nanoscale CeO2 single crystals with an average size from 4 to 60 nm. Results showed the finest crystallites exhibited no strain-induced line broadening, while high temperature annealing resulted in larger grain sizes and significant strains. The observed shift in the x-ray diffraction lattice parameters was assumed to be due to the formation of defects on the lattice, specifically oxygen vacancies. Modeling revealed that the oxygen vacancy concentration ([VO••]) was found to be ≈4×1020/cm3 for the 4 nm crystallites, and decreased two orders of magnitude for larger 60 nm single crystals.
Neutron Star Crustal Plate Tectonics. II. Evolution of Radio Pulsar Magnetic Fields

Spinning-down (or up) neutron star crusts can be stressed beyond their yield strengths by crust neutron superfluid vortex line pinning. Such stresses may then move crustal plates and the magnetic field embedded in them toward the equator in spinning-down radio pulsars. Consequences can include magnetic moment growth during initial spin-down of the youngest pulsars followed by a much slower decrease toward B∼10 11 G in dead pulsars
Sublithospheric loading and plate-boundary forces

Sublithospheric loading arises from anomalous densities in the mantle, such as cool subducting slabs and regions affected by hot spots. Such loading gives rise to isostatic flexure and to tectonic stress in the strong upper lithosphere. Simple models of sublithospheric loading have been studied by finite-element analysis. The maximum loading stress produced by a simple load increases with its width towards the theoretical density-moment function value, but is found to be almost independent of depth for a narrow load (in contrast to a wide load). A layer of low viscosity above the load reduces the stress, depending on its thickness and viscosity. If the lithospheric stress arising from loading is intersected by a zone or plane of weakness, then plate-boundary tractions develop on the adjacent plates resulting from the redistribution of stress. It is shown, by modelling, that ridge push, slab pull and trench suction can be explained in this way.
Use of the Surface Reference Technique for Path Attenuation Estimates from the TRMM Precipitation Radar

Abstract Estimates of rain rate from the precipitation radar (PR) aboard the Tropical Rainfall Measuring Mission (TRMM) satellite require a means by which the radar signal attenuation can be corrected. One of the methods available is the surface reference technique in which the radar surface return in rain-free areas is used as a reference against which the path-integrated attenuation is obtained. Despite the simplicity of the basic concept, an assessment of the reliability of the technique is difficult because the statistical properties of the surface return depend not only on surface type (land/ocean) and incidence angle, but on the detailed nature of the surface scattering. In this paper, a formulation of the technique and a description of several surface reference datasets that are used in the operational algorithm are presented. Applications of the method to measurements from the PR suggest that it performs relatively well over the ocean in moderate to heavy rains. An indication of the reliability of.
qChain: A Blockchain Solution Applied to Citizen-Centric Document Automation

Documents are an important method of registering human’s data and actions of public and private interest that involve one or more authorities. Document automation technology is useful in facilitating processes related to every stage and aspect of document digitalization and management in a rising digital world. Document automation platforms have been progressing to public use, focusing on critical certificates and agreements, very present in legal departments and government authorities, but slowly, they are migrating to wider audiences, focusing more on easing citizen daily lives. Alike any paper document that needs to be authorized, signed, sealed according to importance, and stored securely, these operations performed in network-based systems, need that same treatment digitally. qDocs is a citizen-centric and multi-organization document automation platform designed for citizens and friendly use, focusing on reducing unneeded and exhaustive processes while assuring digital safety and validation. This feature is the concept and implementation of this thesis, qChain, which intends to integrate the qDocs platform with a blockchain-based system, as an immutable database and integrity validator of the system’s reliability and authenticity
EOQ model for an inventory with a linear trend in demand and finite rate of replenishment considering shortages

An economic order quantity (EOQ) model is developed for an item with a deterministic time-dependent demand pattern with a linear (positive) trend. It is assumed that the inventory is replenished at a uniform rate. The model is solved allowing either no shortage or a shortage in the inventory. The procedures of applying the results in practical cases are illustrated with the help of numerical examples.
Momentum Extragradient is Optimal for Games with Cross-Shaped Spectrum

The extragradient method has recently gained a lot of attention, due to its convergence behavior on smooth games. In games, the eigenvalues of the Jacobian of the vector field are distributed on the complex plane, exhibiting more convoluted dynamics compared to minimization. In this work, we take a polynomial-based analysis of the extragradient with momentum for optimizing games with cross-shaped spectrum on the complex plane. We show two results: first, the extragradient with momentum exhibits three different modes of convergence based on the hyperparameter setup: when the eigenvalues are distributed ( i ) on the real line, ( ii ) both on the real line along with complex conjugates, and ( iii ) only as complex conjugates. Then, we focus on the case ( ii ) , i.e., when the spectrum of the Jacobian has cross-shaped structure, as observed in training generative adversarial networks. For this problem class, we derive the optimal hyperparameters and show that the extragradient with momentum achieves accelerated convergence rate.
Nuclear spectra of polar‐ring galaxies

We report the results of spectroscopic observations of eight southern polar-ring galaxies (PRGs), in the wavelength range 5900–7300 A. We find that five out of eight galaxies contain LINERs or Sy nuclei. Taking into consideration all PRGs with available spectral data, we estimate that about half of all PRGs and PRG candidates have either LINER or Seyfert nuclei. The observed widths of the [N ii]λ6583 line in the nuclei of early-type PRGs follow the linewidth–absolute luminosity relation for normal E/S0 galaxies. We found that one of the observed galaxies – ESO 576-G69 – is a new kinematically-confirmed polar-ring galaxy with a spiral host.
Cross-correlation characteristics of OB stars from IUE spectroscopy

We present a catalogue of homogeneous measures of the linewidth parameter, v(e) sin i, for 373 O-type stars and early B supergiants (including the separate components of 25 binary and three triple systems), produced by cross-correlating high-resolution, short-wavelength IUE spectra against a 'template' spectrum of tau Sco. We also tabulate terminal velocities. There are no O supergiants in our sample with v(e) sin i < 65 km s(-1), and only one supergiant earlier than B5 has v(e) sin i < 50 km s(-1), confirming that an important line broadening mechanism in addition to rotation must be present in these objects. A calibration of the area under the cross-correlation peak against spectral type is used to obtain estimates of continuum intensity ratios of the components in 28 spectroscopically binary or multiple systems. At least seven SB2 systems show evidence for the 'Struve-Sahade effect', a systematic variation in relative line strength as a function of orbital phase. The stellar wind profiles of the most rapid rotator in our sample, the O9 III:n* star HD 191423 (v(e) sin i = 436 km s(-1)), show it to have a 'wind-compressed disc' similar to that of HD 93521; this star and other rapid rotators are good candidates for studies of non-radial pulsation.
Cost-effective architecture of decoder circuits and futuristic scope in the era of nano-computing

: Over the past several decades, the goal of Very Large-Scale Integration (VLSI) has been to miniaturise chip size while increasing computing speed and lowering power consumption. At this time, miniaturisation of size, high computing speed, and low power consumption do not appear to be capable of meeting consumer demand due to limitation in transistor geometry. Quantum dot cellular automata (QCA) is a more promising methodology with the potential to optimise power, speed, and area at the nanoscale. Combinational circuit design has received a significant amount of research and development attention in the field of nano-computing. This article proposed design of a decoder with an accurate clocking mechanism in QCA and the best design. In terms of cell count, total area, cell area, area coverage, latency, QCA cost, and quantum cost, the novel 2-to-4 decoder achieves values of 87, 0.10 µm 2 , 0.0281 µm 2 , 28.1, 2.5, 0.625, and 0.25, which is better than the prior work. In comparison to a standard design, the improvements in cell count, total area, cell area, area coverage, latency, QCA cost, and quantum cost are 72.64%, 80%, 72.71%, 28.1%, 64.28%, 97.44%, and 92.85%, respectively.