Miracle-dz/UniFAR-FTUs huggingface dataset:
Study on nanoscale obstructed flow with Molecular Dynamics Simulation method

Obstructed flow around single cylinder and two paratactic cylinders in nanoscale were investigated in the view of discrete particles. Transient and temporal-averaged flow and density fields were obtained to analyse the wake flow. For single cylinder case, Stokes flow, steady vortex flow, periodic vortex-shedding flow with the Karman vortex street and supersonic flow were distinguished based on Re. For two paratactic cylinders case, periodic vortex-shedding flow, periodic vortex-shedding flow with gap-flow, bistable flow and synchronised vortex-shedding flow were observed with different centre-to-centre pitch ratios. Despite of some special characteristics, the results indicate most macroscopic flow patterns still exist in nanoscale.
A Methodological Note on the Estimation of Time Series

ChowLin distributes a series, changing the frequency to a higher one while maintaining the sum over each period, using the Chow-Lin(1971) or related procedure. The newer procedure disaggregate.src is a better choice. Chow and Lin(1971), "Best Linear Unbiased Interpolation, Distribution and Extrapolation of Time Series by Related Series", Review of Economics and Statistics, vol 53, 372-375. Fernandez(1981), "A Methodological Note on the Estimation of Time Series", Review of Economics and Statistics, vol 63, 471-478. Litterman(1983), "A Random Walk, Markov Model for the Distribution of Time Series", JBES, vol 1, 169-173. (This abstract was borrowed from another version of this item.)
Top Local Cohomology Modules

For a finitely generated module M over a commutative Noetherian local ring (R,𝔪), it is shown that there exist only a finite number of non-isomorphic top local cohomology modules for all ideals 𝔞 of R. It is also shown that for a given integer r ≥ 0, if is zero for all 𝔭 in Supp(M), then for all i ≥ r.
Resonantly driven nonlinear density waves in protostellar disks

Recent observations of binary, pre-main-sequence, solar-type stars provide evidence that such systems may coexist with circumstellar disks. The binary disk systems, besides being of general interest for the study of star formation, potentially provide useful tests of companion-disk interaction theories prominent in current hypotheses of planet formation. In this paper, we apply an asymptotic analysis of the nonlinear, resonant interaction of a stellar companion with a disk to understand the dependence of such interactions on the properties of the system: the binary mass ratio, the physical properties of the disk, and the effective dissipation (treated herein as viscosity). The method is based on a WKBJ approximation and exploits the conditions that the disk is thin and much less massive than the primary, but does not require that the companion-induced disturbance be small. Both isothermal and adiabatic responses are treated. Only circular orbit resonances are considered in this paper. It is demonstrated that the temperature of the disk as well as the relative mass of the companion affects the degree of nonlinearity, and that nonlinearity promotes high wave compression ratios, long wavelengths, and increased propagation distances. Nevertheless, the total torque exerted between the companion and the disk is well represented by linear theory. The amplitudes of density disturbances are reduced by viscosity and nonisothermality. Because resonant interactions are generally strong and capable of driving rapid evolution, one might expect observations of systems undergoing strong, resonant-driven evolution to be rare. In this connection, it is pointed out that the m = 1 resonance is distinguished by being anomalously weaker than the others and is therefore of observational interest. It is speculated that, in conditions of intrinsically small dissipation, the propagation of resonant-driven density waves is limited by the tendency of their wavelength to diminish with distance, and that the propagation distance (and therefore the region of the disk to which angular momentum is redistributed) is set by the distance at which the wavelength becomes comparable to the disk thickness.
Variable Thermal Emission from Aquila X-1 in Quiescence

We obtained four Chandra/ACIS-S observations beginning 2 weeks after the end of the 2000 November outburst of the neutron star (NS) transient Aql X-1. Over the 5 month span in quiescence, the X-ray spectra are consistent with thermal emission from a NS with a pure hydrogen photosphere and R∞ = 15.9 (d/5 kpc) km at the optically implied X-ray column density. We also detect a hard power-law tail during two of the four observations. The intensity of Aql X-1 first decreased by 50% ± 4% over 3 months, then increased by 35% ± 5% in 1 month, and then remained constant (<6% change) over the last month. These variations in the first two observations cannot be explained by a change in either the power-law spectral component or the X-ray column density. Presuming a pure hydrogen atmosphere and that R∞ is not variable, the long-term changes can only be explained by variations in the NS effective temperature, from kTeff,∞ = 130 eV, down to 113 eV, and finally increasing to 118 eV for the final two observations. During one of these observations, we observe two phenomena that were previously suggested as indicators of quiescent accretion onto the NS: short-timescale (<104 s) variability (at 32% rms) and a possible absorption feature near 0.5 keV. The possible absorption feature can potentially be explained as being due to a time-variable response in the ACIS detector. Even so, such a feature has not been detected previously from a NS and, if confirmed and identified, can be exploited for simultaneous measurements of the photospheric redshift and NS radius.
Simultaneous and Unambiguous Measurement for Doppler Frequency Shift and Angle of Arrival of a Microwave Signal with High Precision

ABSTRACT A photonic scheme for simultaneously measuring both the Doppler frequency shift (DFS) and angle of arrival (AOA) of a microwave signal based on a polarization division multiplexing dual-parallel Mach-Zehnder modulator (PDM-DPMZM) is proposed. In our scheme, the single-sideband (SSB) modulated signals via PDM-DPMZM are divided into two branches, and so two ac power-phase mapping functions with higher slopes are formed by different polarization processing. Since one ac power-phase curve serves as a calibration line, the system can realize unambiguous AOA measurement with the phase range of −180°~180°. The value and direction of DFS can only be determined using an electrical spectrum analyzer (ESA). In addition, the scheme has a larger operating bandwidth because no filter is required. Simulation results show that the AOA from −83.92° to 83.92° is measured with an error of ±0.9°, and the DFS measurement within ±100 KHz is realized with an error less than ±5 × 10−3 Hz. The characteristics of low error, high precision, and wide bandwidth are important for microwave signal detection.
The first all-sky view of the Milky Way stellar halo with Gaia+2MASS RR Lyrae

We exploit the first Gaia data release to study the properties of the Galactic stellar halo as traced by RR Lyrae. We demonstrate that it is possible to select a pure sample of RR Lyrae using only photometric information available in the Gaia+2MASS catalogue. The final sample contains about 21 600 RR Lyrae covering an unprecedented fraction (similar to 60 per cent) of the volume of the Galactic inner halo (R <28 kpc). We study the morphology of the stellar halo by analysing the RR Lyrae distribution with parametric and non-parametric techniques. Taking advantage of the uniform all-sky coverage, we test halo models more sophisticated than usually considered in the literature, such as those with varying flattening, tilts and/or offset of the halo with respect to the Galactic disc. A consistent picture emerges: the inner halo is well reproduced by a smooth distribution of stars settled on triaxial density ellipsoids. The shortest axis is perpendicular to the Milky Way's disc, while the longest axis forms an angle of similar to 70 degrees with the axis connecting the Sun and the Galactic Centre. The elongation along the major axis is mild (p = 1.27), and the vertical flattening is shown to evolve from a squashed state with q approximate to 0.57 in the centre to a more spherical q approximate to 0.75 at the outer edge of our data set. Within the radial range probed, the density profile of the stellar halo is well approximated by a single power law with exponent alpha = -2.96. We do not find evidence of tilt or offset of the halo with respect to the Galaxy's disc.
Jacobi like bar mode instability of relativistic rotating bodies

We perform some numerical studies of the secular triaxial instability of rigidly rotating homogeneous fluid bodies in general relativity. In the Newtonian limit, this instability arises at the bifurcation point between the Maclaurin and Jacobi sequences. It can be driven in astrophysical systems by viscous dissipation. We locate the onset of instability along several constant baryon mass sequences of uniformly rotating axisymmetric bodies for compaction parameter $M/R=0\char21{}0.275. $ We find that general relativity weakens the Jacobi-like bar mode instability, but the stabilizing effect is not very strong. According to our analysis the critical value of the ratio of the kinetic energy to the absolute value of the gravitational potential energy $(T/|W|{)}_{\mathrm{crit}}$ for a compaction parameter as high as $0.275$ is only $30%$ higher than the Newtonian value. The critical value of the eccentricity depends very weakly on the degree of relativity and for $M/R=0.275$ is only $2%$ larger than the Newtonian value at the onset for the secular bar mode instability. We compare our numerical results with recent analytical investigations based on the post-Newtonian expansion.
Baryonic impact on the dark matter orbital properties of Milky Way-sized haloes

We study the orbital properties of dark matter haloes by combining a spectral method and cosmological simulations of Milky Way-sized galaxies. We compare the dynamics and orbits of individual dark matter particles from both hydrodynamic and $N$-body simulations, and find that the fraction of box, tube and resonant orbits of the dark matter halo decreases significantly due to the effects of baryons. In particular, the central region of the dark matter halo in the hydrodynamic simulation is dominated by regular, short-axis tube orbits, in contrast to the chaotic, box and thin orbits dominant in the $N$-body run. This leads to a more spherical dark matter halo in the hydrodynamic run compared to a prolate one as commonly seen in the $N$-body simulations. Furthermore, by using a kernel based density estimator, we compare the coarse-grained phase-space densities of dark matter haloes in both simulations and find that it is lower by $\sim0.5$ dex in the hydrodynamic run due to changes in the angular momentum distribution, which indicates that the baryonic process that affects the dark matter is irreversible. Our results imply that baryons play an important role in determining the shape, kinematics and phase-space density of dark matter haloes in galaxies.
The Effect of Profitability and Company Size on Company Value with Capital Structure as an Intervening Variable in Food And Beverages Manufacturing Companies for the 2016-2020 Period

This study was conducted to analyze the Effect of Profitability and Firm Size (Size) on Firm Value with Capital Structure as an Intervening Variable in Food & Beverages Manufacturing Companies for the 2016-2020 period. The technique used is the purposive sampling method and the number of samples used is 8 companies with a period of 2016-2020. The analytical tool used in this research is path analysis technique with the help of SmartPLS software version 3.0 for windows. This study uses secondary data, secondary data obtained from the Stock Exchange Gallery, Muhammadiyah University of Sidoarjo. The analytical method used is the Path Analysis method.The results of this study indicate that The results of this study indicate that (1) Profitability has a positive and significant effect on Capital Structure. (2) Company size has a negative and insignificant effect on Capital Structure. (3) Profitability has a positive and significant effect on Firm Value (4) Firm Size has a negative and insignificant effect on Firm Value (5) Firm Size has a positive and significant effect on Firm Value. (6) Profitability has a positive and significant effect on firm value through the capital structure intervening variable. (7) Firm size has a negative and insignificant effect on firm value through the capital structure intervening variable.
Observational evidence of intensified nocturnal urban heat island during heatwaves in European cities

A heatwave (HW) is a large-scale meteorological event characterised by persistent and extremely high-temperature condition. At the local scale, the urban heat island (UHI) is another thermal-related phenomenon defined as an urban area warmer than its surrounding regions due to different surfaces’ capabilities to absorb and store heat. However, the assessment about the effect produced on UHI by HW events is not homogeneous. Indeed, regarding the capability of HWs to influence the urban-rural temperature difference, several studies report different conclusions describing both an exacerbation and a reduction of UHI during HW events. In this context, the present study analyses in situ long records of temperature measurements (20 years) to provide observational shreds of evidence of UHI modification under HW conditions. We examine data from the European Climate Assessment & Dataset and World Meteorological Organization computing the UHI index (UHII) to quantify the UHI effect intensity in 37 European cities during the last 20 summers. The results show an UHII intensification for 28 of the 32 cities affected by positive UHI during extremely high temperatures at night, while substantial variations are not observed during the daytime. The time evolution of UHI during a HW highlights that a more significant and persistent urban-rural temperature gradient explains the UHI intensification. Finally, the relationship between the large and local-scale temperature phenomena reveals that continental high-temperature periods are often associated with prominent temperature differences between small-scale urban and rural environments, assessing the impact of large-scale features on thermal stress at the local scale.
Asteroseismic constraints on active latitudes of solar-type stars: HD 173701 has active bands at higher latitudes than the Sun

We present a new method for determining the location of active bands of latitude on solar-type stars, which uses stellar-cycle-induced frequency shifts of detectable solar-like oscillations. When near-surface activity is distributed in a non-homogeneous manner, oscillation modes of different angular degree and azimuthal order will have their frequencies shifted by different amounts. We use this simple concept, coupled to a model for the spatial distribution of the near-surface activity, to develop two methods that use the frequency shifts to infer minimum and maximum latitudes for the active bands. Our methods respond to the range in latitude over which there is significant magnetic flux present, over and above weak basal ephemeral flux levels. We verify that we are able to draw accurate inferences in the solar case, using Sun-as-a-star helioseismic data and artificial data. We then apply our methods to Kepler data on the solar analogue HD 173701, and find that its active bands straddle a much wider range in latitude than do the bands on the Sun.
Determining the effect of strategic voting on election results

Speculations about whether strategic voting made a difference to the outcome of an election regularly whip up the passions of pundits, party strategists, electoral reformers and scholars alike. Yet, research on strategic voting's political effect has been hampered by the scarcity of data on district level party preferences. We propose the use of Bayesian small area estimation to predict district level preferences from just a handful of survey responses per district and comparing these predictions against election results to estimate how many voters switched sides in each district. We apply the approach to estimate how many seats changed hands as a result of strategic voting at the 1997 and 2001 UK general elections. Despite similar rates of strategic voting in both elections, the number of seats that were affected was markedly greater in 1997. Interestingly, the Liberal Democrats turn out to win the most seats because of strategic voting. We also estimate how many votes went in the ‘wrong’ direction—away from otherwise viable candidates. We validate our results by using journalistic sources and compare them with previous published estimates.
Cosmic ray feedback in the FIRE simulations: constraining cosmic ray propagation with GeV γ-ray emission

We present the implementation and the first results of cosmic ray (CR) feedback in the Feedback In Realistic Environments (FIRE) simulations. We investigate CR feedback in non-cosmological simulations of dwarf, sub-L⋆ starburst, and L⋆ galaxies with different propagation models, including advection, isotropic, and anisotropic diffusion, and streaming along field lines with different transport coefficients. We simulate CR diffusion and streaming simultaneously in galaxies with high resolution, using a two-moment method. We forward-model and compare to observations of γ-ray emission from nearby and starburst galaxies. We reproduce the γ-ray observations of dwarf and L⋆ galaxies with constant isotropic diffusion coefficient $\kappa \sim 3\times 10^{29}\, {\rm cm^{2}\, s^{-1}}$. Advection-only and streaming-only models produce order of magnitude too large γ-ray luminosities in dwarf and L⋆ galaxies. We show that in models that match the γ-ray observations, most CRs escape low-gas-density galaxies (e.g. dwarfs) before significant collisional losses, while starburst galaxies are CR proton calorimeters. While adiabatic losses can be significant, they occur only after CRs escape galaxies, so they are only of secondary importance for γ-ray emissivities. Models where CRs are ‘trapped’ in the star-forming disc have lower star formation efficiency, but these models are ruled out by γ-ray observations. For models with constant κ that match the γ-ray observations, CRs form extended haloes with scale heights of several kpc to several tens of kpc.
Ontological Determinism, non-locality, quantum equilibrium and post-quantum mechanics

In this paper, we extend our previous discussion on ontological determinism, non-locality and quantum mechanics to that of the Sarfatti post-quantum mechanics perspective. We examine the nature of quantum equilibrium and non-equilibrium and uncertainty following the Sarfatti description of this theoretical development, which serves to extend the statistical linear unitary quantum mechanics for closed systems to a locally-retrocausal, non-statistical, non-linear, non-unitary theory for open systems. We discuss how the Bohmian quantum potential has a dependence upon the position of its Bell beable and how Complexity mathematics describes the self-organizing feedback between the quantum potential and its beable allowing nonlocal communication.
Relativistic Envelopes and Gamma-Rays from Neutron Star Mergers

We suggest that neutron star mergers eject an ultrarelativistic envelope of mass m ∼ 10−7 M⊙, which helps explain the gamma-ray burst from GW170817. One ejection mechanism is the ablation of the neutron star surface by the burst of neutrinos in the first 30 μs of the merger. Another, more efficient mechanism for inflating the ultrarelativistic envelope is an internal shock in the massive ejecta from the merger. A strong shock is expected if the merger product is a magnetar, which emits a centrifugally accelerated wind. The shock propagates outward through the ejecta and accelerates in its outer layers at radii r ∼ 109–1010 cm, launching an ultrarelativistic opaque envelope filled with ∼104 photons per nucleon. The Lorentz factor profile of the envelope rises outward and determines its homologous expansion, which adiabatically cools the trapped photons. Once the magnetar loses its differential rotation and collapses into a black hole, a powerful jet forms. It drives a blast wave into the envelope, chasing its outer layers, and eventually catching up with the envelope photosphere at r ∼ 1012 cm. The ultrarelativistic photospheric breakout of the delayed blast wave emits a gamma-ray burst in a broad solid angle around the merger axis. This model explains the gamma-ray pulse from merger GW170817 with luminosity Lγ ∼ 1047 erg s−1, duration , and characteristic photon energy ∼100 keV. The blast-wave Lorentz factor at the envelope photosphere is consistent with Γ ≳ 5, which we derive from the observed light curve of the burst. We suggest future tests of the model.
Three‐Dimensional Thermoelastic Treatment in Spherical Region and its Application to Solid Sphere due to Rotating Heat Source

This paper is concerned with three-dimensional thermoelastic treatment governed by spherical coordinate system. The first part in this paper is devoted to derive the convenient expressions for the displacements and stress components by introducing two functions obtained from the three-dimensional field equations of motion. It is shown that one of them is harmonic, and the other one is a solution of Poisson's equation. In the latter part, we have applied the above treatment to a practical three-dimensional thermoelastic problem. As an illustrative example, we have analyzed the thermal stress problem of a solid sphere due to rotating heat source, and carried out the numerical calculation. Dieser Artikel beschaftigt sich mit Problemen der dreidimensionalen Thermoelastizitat, dargestellt in einem raumlichen Polarkoordinatensystem. Im ersten Teil des Artikels werden die Ausdrucke fur die Verschiebungen und die Spannungskomponenten durch Einfuhrung zweier Funktionen hergeleitet, die aus den dreidimensionalen Feldgleichungen der Bewegung folgen. Es wird gezeigt, das eine davon harmonisch und die andere eine Losung der Poisson-Gleichung ist. Im zweiten Teil wird diese Behandlung auf ein praktische dreidimensionales thermoelastisches Problem angewendet. Als illustratives Beispiel wurden das Warmespannungsproblem eines kugelformigen Festkorpers aufgrund einer rotierenden Warmequelle untersucht und entsprechende numerische Berechnungen durchgefuhrt.
Observational Analysis of Tropical Cyclone Formation. Part III: Budget Analysis

Abstract Vertically integrated budgets of moisture, heat, angular momentum and kinetic energy are calculated from the composite data sets of Part I (McBride, 1981). The transition from cloud cluster to typhoon/hurricane is characterized by a warming of the troposphere and increase of tangential wind. Observations are presented to show that these effects are not restricted to the system's inner core region, but rather take place over a volume extending out to at least 6° latitude radius from the system center. Accordingly, in this paper cyclogenesis is investigated by analyzing budgets over this large scale. The heat budget calculations show that the observed warming of the troposphere is an order of magnitude smaller than the other terms in the budget equation. Most of the released latent heat LP0 is exported laterally through the boundaries of the region through conversion to the term ∇·Vs. The portion of LP0 which is released within the volume acts to counter the net radiative cooling QR. All the compos.