Miracle-dz/UniFAR-FTUs huggingface dataset:
Boltzmann diffusive limit beyond the Navier‐Stokes approximation

Given a normalized Maxwellian μ and n ≥ 1, we establish the global‐in‐time validity of a diffusive expansion $$(0.1) \,\,\,\,\,\,\,\,\,\,\,\,\,\,\, F^{\varepsilon}(t,x,v)=\mu+\sqrt{\mu} \left\{ \varepsilon f_{1}(t,x,v)+\varepsilon^{2}f_{2}(t,x,v)+\cdots+\varepsilon^{n}f_{n}^{\varepsilon}(t,x,v) \right\} ,$$ for a solution Fε to the rescaled Boltzmann equation (diffusive scaling) $$(0.2) \,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \varepsilon\partial_{t}F^{\varepsilon}+v\cdot\nabla_{x}F^{\varepsilon} = {1 \over \varepsilon}Q(F^{\varepsilon},F^{\varepsilon})$$ inside a periodic box 𝕋3. We assume that in the initial expansion (0.1) at t = 0, the fluid parts of these fm(0,x,v) have arbitrary divergence‐free velocity fields as well as temperature fields for all 1 ≤ m ≤ n while f1(0,x,v) has small amplitude in H2. For m ≥ 2, these fm(t,x,v) are determined by a sequence of linear Navier‐Stokes‐Fourier systems iteratively. More importantly, the remainder f nε (t,x,v) is proven to decay in time uniformly in ε via a unified nonlinear energy method. In particular, our results lead to an error estimate for f1(t,x,v), the well‐known Navier‐Stokes‐Fourier approximation, and beyond. The collision kernel Q includes hard‐sphere, the cutoff inverse‐power, as well as the Coulomb interactions. © 2005 Wiley Periodicals, Inc.
Convergence of virial expansions

Some bounds are obtained on R(V), the radius of convergence of the density expansion for the logarithm of the grand partition function of a system of interacting particles in a finite volume V, and on R, the radius of convergence of the corresponding infinite‐volume expansion (the virial expansion). A common lower bound on R(V) and R is 0.28952/(u+1)B, where u ≡ exp [−Min s−1Σi<j≤s 2φ(xi−xj)]/KT [so that u ≥ 1, with equality for nonnegative φ(r)], B ≡ ∫|e−φ (r)/KT−1| d3 r, and φ(r) is the binary interaction potential; the irreducible Mayer cluster integrals have the related upper bounds βk ≤ [(u+1)B/0.28952]k/k[u = 1, when φ(r) ≥ 0]. For potentials with hard cores the maximum density is an upper bound on R(V), though possibly not on R; an example shows how both R(V) and R can be less than the maximum density, even if there is no phase transition. A theorem is proved, analogous to Yang and Lee's theorem on uniform convergence in the complex z plane, defining a class of domains in the complex ρ plane within.
Bending Frequency Of A Rotating Timoshenko Beam With General Elastically Restrained Root

Abstract The upper bound of the fundamental bending frequency of a rotating uniform Timoshenko beam with general elastically restrained root is derived via Rayleigh's principle. Comparing the upper bound with the results in the existing literature and those obtained by the transfer matrix method reveals that the upper bound is quite reliable. It can be found that as the rigidities of the elastic at root are decreased, the difference between the fundamental bending frequency evaluated for a Timoshenko beam and that evaluated for a Bernoulli-Euler beam is decreased. In addition, the effect of rotational speed and slenderness ratio on the error of the upper bound and the influence of root elastic restraints on the fundamental bending frequency are examined.
Near‐field and far‐field sound radiation from a line‐driven fluid‐loaded infinite flat plate having periodic and non‐periodic attached rib stiffeners

Abstract : The far-field and near-field solutions for the radiated acoustic pressure fro a line-driven fluid-loaded, rib-stiffened thin elastic plate have been obtained. The plate has been configured to have two sets of rib-stiffeners, though the formulation given may be extended to include additional rib-stiffener sets. The stiffeners composing a given set are identical and are spaced periodically with distance Q. However, one set of stiffeners is shifted by an amount from the other set. In this manner, portions of the plate may be configured with repeating sections having non-periodic rib spacing. The stiffeners exert reactive forces upon the plate, but not angular moments. Fluid loading is included on the upper surface of the plate while the lower surface is unloaded, except for a time harmonic line force applied normal to the lower surface. Expressions are derived, for the special case of periodic inter-rib spacing, which give the wavenumbers at which the magnitude of the wavenumber response obtains relative maximum and minimum values. For a stiffened plate, it is seen that excitation frequencies below coincidence generate large magnitude supersonic wavenumber components.
Comparison of continuum and particle simulations of expanding rarefied flows

Comparisons of Navier-Stokes solutions and particle simulations for a simple two-dimensional model problem at a succession of altitudes are performed in order to assess the importance of rarefaction effects on the base flow region. In addition, an attempt is made to include 'Burnett-type' extensions to the Navier-Stokes constitutive relations. The model geometry consists of a simple blunted wedge with a 0.425 meter nose radius, a 70 deg cone half angle, a 1.7 meter base length, and a rounded shoulder. The working gas is monatomic with a molecular weight and viscosity similar to air and was chosen to focus the study on the continuum and particle methodologies rather than the implementation of thermo-chemical modeling. Three cases are investigated, all at Mach 29, with densities corresponding to altitudes of 92 km, 99 km, and 105 km. At the lowest altitude, Navier-Stokes solutions agree well with particle simulations. At the higher altitudes, the Navier-Stokes equations become less accurate. In particular, the Navier-Stokes equations and particle method predict substantially different flow turning angle in the wake near the after body. Attempts to achieve steady continuum solutions including 'Burnett-type' terms failed. Further research is required to determine whether the boundary conditions, the equations themselves, or other unknown causes led to this failure.
IRAS observations of an optically selected sample of interacting galaxies

IRAS observations of a large, morphologically selected sample of strongly interacting disk-type galaxies have demonstrated that galaxy-galaxy collisions can lead to enhanced infrared emission, but not in all cases. Infrared luminosities of the interacting galaxies span a large range, but are about a factor of 2 higher, on average, than those of isolated disk galaxies. The data suggest the existence of a cutoff in blue luminosity, below which no galaxies show markedly enhanced infrared emission. Only the most strongly interacting systems in the sample show extreme values of infrared excess, suggesting that deep, interpenetrating collisions are necessary to drive infrared emission to extreme levels. Comparisons with optical indicators of star formation show that infrared excess and color temperatures correlate with the level of star-formation activity in the interacting galaxies. All interacting galaxies in our sample that exhibit an infrared excess and have higher than normal color temperatures also have optical indicators of high levels of star formation. It is not necessary to invoke processes other than star formation to account for the enhanced infrared luminosity in this sample of interacting galaxies. 49 references.
STRUCTURAL ORIGIN OF V-DEFECTS AND CORRELATION WITH LOCALIZED EXCITONIC CENTERS IN INGAN/GAN MULTIPLE QUANTUM WELLS

In the growth of InGaN/GaN multiple quantum well (MQW) structures, a novel defect (called the “V-defect”) initiates at threading dislocations in one of the first quantum wells in a MQW stack. This defect is common to almost all InGaN MQW heterostructures. The nature of the V-defect was evaluated using transmission electron microscopy (TEM), scanning TEM (STEM), and low-temperature cathodoluminescence (CL) on a series of In0.20Ga0. 80N/GaN MQW samples. The structure of the V-defect includes buried side-wall quantum wells (on the {1011} planes) and an open hexagonal inverted pyramid which is defined by the six {1011} planes. Thus, in cross section this defect appears as an open “V”. The formation of the V-defect is kinetically controlled by reduced Ga incorporation on the pyramid walls ({1011} planes). The V-defect is correlated with the localized excitonic recombination centers that give rise to a long-wavelength shoulder in photoluminescence (PL) and CL spectra. This long-wavelength shoulder has the fol.
Uniqueness in Determining Polygonal Periodic Structures

We consider the inverse problem of recovering a two-dimensional perfectly reflecting diffraction grating from scattered waves measured above the structure. We establish the uniqueness within the class of general polygonal grating profiles by a minimal number of incoming plane waves, without excluding Rayleigh frequencies and further geometric constraints on the profile. This extends and improves the uniqueness results of Elschner, Schmidt and Yamamoto [Inverse Problems 19 (2003), 779–787].
Preparation and Piezoelectricity of Piezoelectrets Made of Polytetrafluoroethylene

Polytetrafluoroethylene (PTFE) films with void structure are prepared by a fusion bonding process. Such void PTFE films are piezoelectric after proper corona charging. The maximum quasi-static piezoelectric d 33 coefficients of 220 pC/N are achieved. The applied pressure dependence of piezoelectric d 33 coefficients for the void films is associated with the structure of the films. The piezoelectric response of the films is dependent on the duration of the applied force, which is apparently due to the creep of the material.
Resist nanokirigami for multipurpose patterning

Abstract Resist-based patterning solutions play essential roles in modern micro- and nanoscale science and technology. The commonly used ‘resist’ patterning strategy depends on selective-area scission or cross-linking of resist molecules under the action of an energy beam. In this work, we propose and demonstrate a different resist-patterning strategy, termed ‘resist nanokirigami’, in which the resist structures are defined by their outlines and revealed by selective mechanical peeling of the unwanted resist film. Unlike conventional resist-based patterning processes, the final resist-nanokirigami structures do not undergo exposure and the exposure area is dramatically reduced. With these two advantages, a variety of functional structures that are difficult or impossible to fabricate by conventional processes, such as inverse nanostructures and their oligomers, multi-scale electrodes and freestanding plasmonic nanogaps, can be easily achieved with much higher efficiency. Thus, with its unique and complementary capabilities, the resist-nanokirigami process provides a new patterning solution that expands the family of lithography techniques and will play a significant role in fabricating multi-scale functional structures.
Magnetism mechanism in ZnO and ZnO doped with nonmagnetic elements X (X = Li, Mg, and Al): A first-principles study

First-principles calculations are performed to study the magnetism mechanism in undoped ZnO and ZnO doped with nonmagnetic elements X (X = Li, Mg, and Al). In undoped ZnO, it is found that the Zn vacancy is spin-polarized with a magnetic moment of 1.54 μB. The ferromagnetic coupling between two Zn vacancies is favorable in energy and a band coupling model is used to explain the magnetic coupling. In ZnO doped with nonmagnetic elements X, the magnetism is also attributed to the presence of Zn vacancies. The introduction of X reduces the formation energy of Zn vacancy and stabilizes it to some extent.
Ultraviolet spectropolarimetry of high-redshift quasars with the Hubble Space Telescope

Ultraviolet spectropolarimetry of three bright high-redshift low-polarization quasars (LPQs) was obtained with the Faint Object Spectrograph of the Hubble Space Telescope (HST). Two of the quasars, PG 1634+706 and PG 2302+029, had polarizations p approximately = 0.5%-1.0% throughout the ultraviolet, and showed no significant variation of polarization amplitude or position angle with wavelength. PG 2302+029 was also marginally (2.4 sigma) circularly polarized in the optical continuum. For the highest redshift quasar, PG 1222+228 (Ton 1530), the polarization was measured down to rest wavelengths below 800 A. Although the continuum of PG 1222+228 was weakened by Lyman limit absorption from an intergalactic gas cloud, the polarization increased sharply from 1% to about 4.5%, a change of 4 sigma significance. This abrupt rise in polarization does not appear attributable to any known instrumental artifact. These UV polarizations were only slightly less than those previously observed for these same objects in the optical. The polarization spectra were flat with a typical slope of the polarized flux pF(sub nu) proportional to nu(exp -0.8 +/- 0.5). Unlike the case of several high luminosity Seyfert 1 nuclei studied previously, polarization caused by scattering from dust grains does not provide the best fit to the polarization spectra of these luminous quasars. These observed spectra are consistent with a wavelength-independent polarization proportional to the total nonstellar light or, possibly, to the contribution of the blue thermal component. The polarization spectra have insufficient signal-to-noise to locate the scatterers with respect to the continuum source and the much larger broad line region. A decrease in amplitude and rotation of the position angle of the polarization vector at the shortest wavelengths, which could result from general relativistic effects near a spinning black hole, was not observed. In fact, in PG 1222+228, the polarization was observed to increase at the shortest wavelengths. The rise in polarization with frequency is so sharp that it cannot be due to any wavelength-independent polarizing mechanism at any radius in an accretion disk. Such a rise could be attributable, for example, to a relative increase in scattering opacity over absorption at higher frequencies.
Characteristic Functions of Means of Distributions Chosen from a Dirichlet Process

Let P be a Dirichlet process with parameter a on (R, B), where R is the real line, B is the a-field of Borel subsets of R and a is a non-null finite measure on (R, B). By the use of characteristic functions we show that if Q(.) = a( . )/a(R) is a Cauchy distribution then the mean fR x dP(x) has the same Cauchy distribution and that if Q is normal then the distribution of the mean can be roughly approximated by a normal distribution. If the 1st moment of Q exists, then the distribution of the mean is different from Q except for a degenerate case. Similar results hold also in the multivariate case.
UvA-DARE (Digital Academic Repository) Of monkeys and men

For decades sequential sampling models have successfully accounted for human and monkey decision-making, relying on the standard assumption that decision makers maintain a pre-set decision standard throughout the decision process. Based on the theoretical argument of reward rate maximization, some authors have recently suggested that decision makers become increasingly impatient as time passes and therefore lower their decision standard. Indeed, a number of studies show that computational models with an impatience component provide a good fit to human and monkey decision behavior. However,
2 Evolutionary Cognitive Psychology

1973) and cognitive (Bruner, 1956; Chomsky, 1975; Newell and Simon, 1972) psychological frameworks have distinct roots, yet both are interested in understanding why humans are the way they are. While human development could be viewed as a series of random co-occurrences, evolutionary frameworks have proposed that the evolutionary processes underlying the modern human brain were non-random (Duchaine et al., 2001). Specifically, the reason modern cognitions have their modern structures is due to how they simultaneously evolved. That is, to understand the driving forces behind human cognition, it is vital to consider the context in which an individual’s processing is most efficient. As such, it is necessary to consider the advantages these adaptations would have provided our Paleolithic ancestors as they interacted with each other within a huntinggathering society (Cosmides and Tooby, 2013; Price and Brown, 1985). According to the influential work by Darwin (1859; see also Dawkins, 1976) that has come to shape the framework for evolutionary theory, species (including humans) come to evolve as a result of individuals benefiting from genes that allow for successful reproduction. Reproductive success encompasses qualities that allow the individual to improve longevity enough to procreate as well as attract prospective mates. After all, less beneficial traits that dissuade mate attraction, even if they prolong the lifespan, will be transmitted at a lower rate. Evolutionary psychology can be used as a framework in which to organize and understand a pattern of results from any domain (see Confer et al., 2010). It is used to answer the question of why current behaviors and physiology operate in their present state, by addressing adaptive functioning in terms of the specific internal and environmental input used to influence their development, activation, and expression (Cosmides and Tooby, 2013). By carefully analyzing the instances 2
An auxiliary differential equation FDTD method for anisotropic magnetized plasmas

An auxiliary differential equation finite-difference time-domain (ADE-FDTD) methodology for anisotropic magnetized plasmas is derived. The method is based on a difference approximation of the auxiliary differential equation. A comparison with the JEC method is included. The CPU time saving by several times and accuracy of the method are confirmed by computing the reflection and transmission through a magnetized plasma layer, with the direction of propagation parallel to the direction of the biasing field.
ON COMPUTING L ′ / L ( 1 , χ

We describe how to efﬁciently compute L ′ / L ( 1 , χ ) using the Fast Fourier Transform algorithm. In particular, we will show how to combine the decimation in frequency (DIF) strategy with the reﬂection formulae of the special functions involved in the computations. We will also mention how to efﬁ-ciently compute such special functions.
Structural realism: A critical appraisal.

Three principal forms of structural realism are distinguished in this thesis: weak epistemic structural realism (WESR), strong epistemic structural realism (SESR) and ontic structural realism (OSR). In chapter 1, it is argued that the positive argument in favour of WESR, i.e. the claim that it can accommodate the no miracles argument and the pessimistic induction is unconvincing, because (i) the no miracles argument is flawed, so it is no particular virtue of WESR that it can accommodate it and (ii) it is not clear that WESR really can accommodate the pessimistic induction. In chapter 2, it is argued that there are unresolved difficulties in drawing the observable/unobservable distinction (or an appropriate alternative distinction) in a way that is suitable for the WESRist's purposes. In chapter 3, it is argued that the main argument for SESR is unconvincing, because it is based on Russell's principle of acquaintance (or a modern variant of this principle), a principle for which no substantial argument has been given and which has absurd consequences (as shown in appendix 2). In chapter 4, it is argued that neither the WESRist nor the SESRist has provided a convincing response to Newman's objection. In chapter 5, it is argued that, depending on how one interprets the doctrine, OSR is either (i) wholly untenable or (ii) conventional scientific realism (or antirealism) combined with the traditional metaphysical view that objects are bundles of properties and that in the latter case the doctrine has some plausibility, but the arguments that have been adduced in favour of it are inconclusive. The thesis is concluded with a sketch of the sort of position in the scientific realism debate that I find more attractive.
The Antecedent Large-Scale Conditions of the “Perfect Storms” of Late October and Early November 1991

Abstract The “Perfect Storms” (PSs) were a series of three high-impact extratropical cyclones (ECs) that impacted North America and the North Atlantic in late October and early November 1991. The PSs included the Perfect Storm in the northwest Atlantic, a second EC over the North Atlantic that developed from the interaction of the PS with Hurricane Grace, and a third EC over North America commonly known as the “1991 Halloween Blizzard. ” The PSs greatly impacted the North Atlantic and North America with large waves, coastal flooding, heavy snow, and accumulating ice, and they also provided an opportunity to investigate the physical processes that contributed to a downstream baroclinic development (DBD) episode across North America that culminated in the ECs. Downstream baroclinic development resulted from an amplification of the large-scale flow over the North Pacific that was influenced by anomalous tropical convection, the recurvature and extratropical transition of western North Pacific Tropical Cyclone.
The Rising Entropy of English in the Attention Economy

We present evidence that the word entropy of American English has been rising steadily since around 1900, contrary to predictions from existing sociolinguistic theories. We also find differences in word entropy between media categories, with short-form media such as news and magazines having higher entropy than long-form media, and social media feeds having higher entropy still. To explain these results we develop an ecological model of the attention economy that combines ideas from Zipf's law and information foraging. In this model, media consumers maximize information utility rate taking into account the costs of information search, while media producers adapt to technologies that reduce search costs, driving them to generate higher entropy content in increasingly shorter formats.
MAViL: Masked Audio-Video Learners

We present Masked Audio-Video Learners (MAViL) to train audio-visual representations. Our approach learns with three complementary forms of self-supervision: (1) reconstruction of masked audio and video input data, (2) intra- and inter-modal contrastive learning with masking, and (3) self-training by reconstructing joint audio-video contextualized features learned from the first two objectives. Pre-training with MAViL not only enables the model to perform well in audio-visual classification and retrieval tasks but also improves representations of each modality in isolation, without using information from the other modality for fine-tuning or inference. Empirically, MAViL sets a new state-of-the-art on AudioSet (53.1 mAP) and VGGSound (67.1% accuracy). For the first time, a self-supervised audio-visual model outperforms ones that use external supervision on these benchmarks.