Miracle-dz/UniFAR-FTUs huggingface dataset:
Technical Report Series Center for Data and Simulation Science

For complex model problems with coeicient or material distributions with large jumps along or across the domain decomposition interface, the convergence rate of classic domain decomposition methods for scalar elliptic problems usually deterio‚ rates. In particular, the classic condition number bounds [1, 12] will depend on the contrast of the coeicient function. As a remedy, diferent adaptive coarse spaces, e.g, [13, 4], have been developed which are obtained by solving certain generalized eigenvalue problems on local parts of the interface, i.e., edges and/or faces. A selec‚ tion of the resulting eigenmodes, based on a user‚deined tolerance, is then used to enrich the coarse space and retain a robust convergence behavior. However, the setup and the solution of the eigenvalue problems usually take up a signiicant amount of time in a parallel computation, and for many realistic coeicient distributions, a relatively high number of the eigenvalue problems is unnecessary since they do not result in any additional coarse basis functions. Unfortunately, it is not known a priori, which eigenvalue problems are unnecessary and thus can be omitted. In order to reduce the number of eigenvalue problems, we have proposed to train a neural network to make an automatic decision which of the eigenvalue
Plasma Modes along the Open Field Lines of a Neutron Star

We consider electrostatic plasma modes along the open field lines of a rotating neutron star. Goldreich-Julian charge density in general relativity is analyzed for the neutron star with zero inclination. It is found that the charge density is maximum at the polar cap and remains almost the same in a certain extended region of the pole. For a steady state Goldreich-Julian charge density we found the usual plasma oscillation along the field lines; plasma frequency resembles the gravitational redshift close to the Schwarzschild radius. We study the nonlinear plasma mode along the field lines. From the system of equations under general relativity, a second-order differential equation is derived. The equation contains a term that describes the growing plasma modes near Schwarzschild radius in a black hole environment. The term vanishes with the distance far away from the gravitating object. For initially zero potential and field on the surface of a neutron star, Goldreich-Julian charge density is found to create the plasma mode, which is enhanced and propagates almost without damping along the open field lines. We briefly outline our plan to extend the work for studying soliton propagation along the open field lines of strongly gravitating objects.
The near-infrared counterpart of 4U 1636-53

The optical counterpart of the neutron star X-ray binary and well known X-ray burster, 4U 1636-53 (= 4U 1636-536 = V801 Ara) has been well studied for three decades. However to date, no infrared studies have been reported. Our aims are to identify and investigate the near-infrared (NIR) counterpart of 4U 1636-53. We present deep, K_s-band (2.2 micron) imaging of the region of 4U 1636-53 taken with the Infrared Spectrometer And Array Camera (ISAAC) on the Very Large Telescope. Archival optical and UV data are used to infer the 0.2-2.2 micron spectral energy distribution (SED). One star is located at coordinates alpha =16:40:55.57, delta =-53:45:05.2 (J2000; 1 sigma positional uncertainty of ~ 0.3 arcsec) which is consistent with the known optical position of 4U 1636-53; its magnitude is K_s = 16.14 +- 0.12. This star is also detected in the 2MASS survey in J-band and has a magnitude of J = 16.65 +- 0.22. Under the assumption that the persistent emission is largely unvarying, the 0.4-2.2 micron de-reddened SED can be described by a power law; F_nu propto nu^(1.5 +- 0.3), with some possible curvature (F_nu propto nu^(<= 1.5)) at 0.2-0.4 microns. The SED can be approximated by a blackbody of temperature ~ 27 000 K. This is typical for an active low-mass X-ray binary, and the emission can be explained by the outer regions of a (likely irradiated) accretion disc. We therefore interpret this K_s-band star as the NIR counterpart.
The integrated calcium II triplet as a metallicity indicator: comparisons with high-resolution [Fe/H] in M31 globular clusters

Medium resolution (R=4,000 to 9,000) spectra of the near infrared Ca II lines (at 8498, 8542, and 8662 A) in M31 globular cluster integrated light spectra are presented. In individual stars the Ca II triplet (CaT) traces stellar metallicity; this paper compares integrated CaT strengths to well determined, high precision [Fe/H] values from high resolution integrated light spectra. The target globular clusters cover a wide range in metallicity (from [Fe/H] = -2.1 to -0.2). While most are older than 10 Gyr, some may be of intermediate age (2-6 Gyr). A handful (3-6) have detailed abundances (e.g. low [Ca/Fe]) that indicate they may have been accreted from dwarf galaxies. Using various measurements and definitions of CaT strength, it is confirmed that for GCs with [Fe/H] < -0.4 and older than 2 Gyr the integrated CaT traces cluster [Fe/H] to within about 0.2 dex, independent of age. CaT lines in metal rich GCs are very sensitive to nearby atomic lines (and TiO molecular lines in the most metal rich GCs), largely due to line blanketing in continuum regions. The [Ca/Fe] ratio has a mild effect on the integrated CaT strength in metal poor GCs. The integrated CaT can therefore be safely used to determine rough metallicities for distant, unresolved clusters, provided that attention is paid to the limits of the measurement techniques.
Asymptotic properties of unbounded quadrature domains the plane

We prove that if Ω is a simply connected quadrature domain (QD) of a distribution with compact support and the point of infinity belongs to the boundary, then the boundary has an asymptotic curve that is a straight line, parabola or infinite ray. In other words, such QDs in the plane are perturbations of null QDs.
Magnetic Drive-Trains Pole-Slipping Inducements and Overload Speed Reduction

- The paper presents an analysis of magnetic drive train (MDT) pole-slipping and an amelioration strategy to reduce uncontrolled load-side speed when subject to pole-slipping. Initially, the pole-slipping inducements of MDTs are deduced based on the assumption that driving controllers are designed with sufficient servo rigidity. Subsequently, in order to avoid initiating degrading coupling torque oscillations, the transient response of the induced coupling torque is analysed. Next, the paper provides a load-side speed reduction methodology based on load-side speed estimation, synchronization, and piecewise electromagnetic torque excitation to reduce the potential for (mechanical or temperature induced) damage to mechanical components (eg. bearings) as a result of uncontrolled speed during pole-slipping. More generally, consideration of electromagnetic torque production for flexible systems, such as MDTs, possessing variable/nonlinear stiffness, is addressed to ameliorate the chances of inducing pole-slipping.
Infinite order corks via handle diagrams

The author recently proved the existence of infinite order corks, arXiv:1603.05090. The present paper exhibits the first handle diagrams of this phenomenon, by translating the earlier proof into this language. Preliminary notes for this work also provided key diagrams for Akbulut's recent posting arXiv:1605.09348. While that paper provides a different viewpoint, we show that at a fundamental level the technique is equivalent, and the proof sketched in that paper is a special case of the author's diagrammatic translation of the original. The cork twists defined in the author's original paper and drawn in the subsequent papers are twists on incompressible tori. We give conditions guaranteeing that such twists do not change the diffeomorphism type of a 4-manifold, partially answering a question from the original paper.
Journal Economics Education and Entrepreneurship Entrepreneurial Based University: Case Study Approach

Entrepreneurial-based university (EBU) is breaking into one of the chance-leading strategies of developing an effective entrepreneurial development program within a spiritual religious framework. The purpose of this study is to examine how college entrepreneurship management is implemented in West Sumatra province to foster student entrepreneurship. The research was qualitative in nature, with descriptive analysis techniques used. Techniques for data retrieval include interviews, structured stickies, and observation. The research is being carried out at Universitas Negeri Padang (UNP) of West Sumatra Province. The framework of the factual model of college entrepreneurial management was built on the factual data of subsequent research results. The results show that development programs are carried out through the optimization of student activity units. Through the effective implementation of managerial functions of strategic policy planning in the form of statutes, strategic plans, designation of campus development priority programs, establishment of business units, and entrepreneurship programs, leadership plays a role in developing student entrepreneurship; Organizing functions are performed in the form of task formalization and managing restructuring; leadership functions in the concept of view, appreciate, leading, understand, and evaluate (VALUE) in the spiritual religious frame–muslimpreneur; and supervision functions are performed both against program implementation and budget liability in the development of student entrepreneurship.
Local Smoothing Estimates near a Trapped Set with Infinitely Many Connected Components

We prove a local smoothing result for the Schr\"odinger equation on a class of surfaces of revolution which have infinitely many trapped geodesics. Our main result is a local smoothing estimate with loss (compared to \cite{ChMe-lsm}) depending on the accumulation rate of the critical points of the profile curve. The proof uses an h-dependent version of semiclassical propagation of singularities, and a result on gluing an h-dependent number of cutoff resolvent estimates.
How to close the skill gap? Parental Background and Children’s Skill Development in Indonesia

Preexisting inequalities in socioeconomic status can drive differences in children’s cognitive skill development and parents’ reactions to child development policies influencing policy effectiveness. To analyze the role of parental background and investments (nutrition diversity and schooling expenditure) in this process, I estimate a dynamic structural model using data from Indonesia. I find two main factors contribute to the adult skill gap: household income and parental education, which influences the productivity of investments. Using the model, I simulate three policies: unconditional cash transfers, nutrition, and schooling price subsidies. To compare their long-run effects on adult skills, I account for parents adjusting their investment behavior in response to policies. Given the same cost, a) subsidizing food prices is more effective than subsidizing schooling expenditure, and b) both are more effective than cash transfers. As I find nutrition and schooling to be complements, a price decrease incentivizes parents to increase both inputs. With cash transfers, parents also increase investments but increase consumption relatively more as price incentives do not change. Nutrition subsidies reduce inequality most effectively, as parents with lower education react stronger to food price changes and, consequently, increase child investments more than parents with higher education. They do so as they spend a larger share of investments on nutrition. Further, nutrition subsidies implemented alone are more cost-effective than any combination of the three policies.
Kohnert Polynomials

Abstract We associate a polynomial to any diagram of unit cells in the first quadrant of the plane using Kohnert’s algorithm for moving cells down. In this way, for every weak composition one can choose a cell diagram with corresponding row-counts, with each choice giving rise to a combinatorially-defined basis of polynomials. These Kohnert bases provide a simultaneous generalization of Schubert polynomials and Demazure characters for the general linear group. Using the monomial and fundamental slide bases defined earlier by the authors, we show that Kohnert polynomials stabilize to quasisymmetric functions that are nonnegative on the fundamental basis for quasisymmetric functions. For initial applications, we define and study two new Kohnert bases. The elements of one basis are conjecturally Schubert-positive and stabilize to the skew-Schur functions; the elements of the other basis stabilize to a new basis of quasisymmetric functions that contains the Schur functions.
On the structure of positive maps II: low dimensional matrix algebras

We use a new idea that emerged in the examination of exposed positive maps between matrix algebras to investigate in more detail the differences and similarities between unital positive maps on M2(C) and M3(C). Our main tool stems from classical Grothendieck theorem on tensor product of Banach spaces and is an older and more general version of Choi-Jamiolkowski isomorphism between positive maps and block positive Choi matrices. It takes into account the correct topology on the latter set that is induced by the uniform topology on positive maps. In this setting, we show that in M2(C) case a large class of nice positive maps can be generated from the small set of maps represented by self-adjoint unitaries, 2Px with x maximally entangled vector and p⊗1 with p rank 1 projector. We indicate problems with passing this result to M3(C) case. Among similarities, in both M2(C) and M3(C) cases any unital positive map represented by self-adjoint unitary is unitarily equivalent to the transposition map. Consequently, .
ABUNDANCE PROFILING OF EXTREMELY METAL-POOR STARS AND SUPERNOVA PROPERTIES IN THE EARLY UNIVERSE

After the big bang nucleosynthesis, the first heavy element enrichment in the universe was made by a supernova (SN) explosion of a population (Pop) III star (Pop III SN). The abundance ratios of elements produced from Pop III SNe are recorded in abundance patterns of extremely metal-poor (EMP) stars. The observations of the increasing number of EMP stars have made it possible to statistically constrain the explosion properties of Pop III SNe. We present Pop III SN models whose nucleosynthesis yields well reproduce, individually, the abundance patterns of 48 such metal-poor stars as [Fe/H] ≲ − 3.5. We then derive relations between the abundance ratios of EMP stars and certain explosion properties of Pop III SNe: the higher [(C + N)/Fe] and [(C + N)/Mg] ratios correspond to the smaller ejected Fe mass and the larger compact remnant mass, respectively. Using these relations, the distributions of the abundance ratios of EMP stars are converted to those of the explosion properties of Pop III SNe. Such distributions are compared with those of the explosion properties of present day SNe: the distribution of the ejected Fe mass of Pop III SNe has the same peak as that of the present day SNe but shows an extended tail down to ∼10−2–10−5 M☉, and the distribution of the mass of the compact remnant of Pop III SNe is as wide as that of the present-day, stellar-mass black holes. Our results demonstrate the importance of large samples of EMP stars obtained by ongoing and future EMP star surveys and subsequent high-dispersion spectroscopic observations in clarifying the nature of Pop III SNe in the early universe.
Hot ammonia around young O-type stars - II. JVLA imaging of highly excited metastable NH3 masers in W51-North

We have used the JVLA at the 1 cm band to map five highly-excited metastable inversion transitions of ammonia, (J,K)=(6,6), (7,7), (9,9), (10,10), and (13,13), in W51 IRS2 with ~0.2 angular resolution. We present detections of both thermal (extended) ammonia emission in the five inversion lines, with rotational states ranging in energy from about 400 to 1700 K, and point-like ammonia maser emission in the (6,6), (7,7), and (9,9) lines. The thermal ammonia emits around a velocity of 60 km/s, near the cloud's systemic velocity, is elongated in the east-west direction across 4" and is confined by the HII regions W51d, W51d1, and W51d2. The ammonia masers are observed in the eastern tip of the dense clump traced by thermal ammonia, offset by 0.65" to the East from its emission peak, and have a peak velocity at ~47.5 km/s. No maser components are detected near the systemic velocity. The ammonia masers are separated by 0.65" (3500 AU) from the (rare) vibrationally-excited SiO masers, excited by the deeply-embedded YSO W51-North. This excludes that the two maser species are excited by the same object. Interestingly, the ammonia masers originate at the same sky position as a peak in a submm line of SO2 imaged with the SMA, tracing a face-on circumstellar disk/ring around W51-North. In addition, the thermal emission from the most highly excited ammonia lines, (10,10) and (13,13), shows two main condensations, the dominant one towards W51-North with the SiO/H2O masers, and a weaker peak at the ammonia maser position. We propose a scenario where the ring seen in SO2 emission is a circumbinary disk surrounding (at least) two high-mass YSOs, W51-North (exciting the SiO masers) and a nearby companion (exciting the ammonia masers), separated by 3500 AU. This finding indicates a physical connection (in a binary) between the two rare SiO and ammonia maser species.
Cwikel's theorem and the CLR inequality

We give a short proof of the Cwikel-Lieb-Rozenblum (CLR) bound on the number of negative eigenvalues of Schr\"odinger operators. The argument, which is based on work of Rumin, leads to remarkably good constants and applies to the case of operator-valued potentials as well. Moreover, we obtain the general form of Cwikel's estimate about the singular values of operators of the form $f(X) g(-i\nabla)$.
Waterfalls around protostars: Infall motions towards Class 0/I envelopes as probed by water

Abridged abstract: For stars to form, material must fall inwards from core scales through the envelope towards the central protostar. The velocity profile around protostars is poorly constrained. 6 Class 0 protostars and one Class I protostars observed with HIFI on board Herschel as part of the "Water in star-forming regions with Herschel" (WISH) survey show infall signatures in water line observations. We use 1-D non-LTE RATRAN radiative transfer models of the observed water lines to constrain the infall velocity and chemistry in the protostellar envelopes of these sources. We assume a free-fall velocity profile and, having found the best fit, vary the radii over which infall takes place. In the well-studied Class 0 protostar NGC1333-IRAS4A we find that infall takes place over the whole envelope to which our observations are sensitive (r>~1000 AU). For 4 sources infall takes place on core to envelope scales (i.e. ~10000-3000 AU). In 2 sources the inverse P-Cygni profiles seen in the ground-state lines are more likely due to larger-scale motions or foreground clouds. Models including a simple consideration of the chemistry are consistent with the observations, while using step abundance profiles are not. The non-detection of excited water in the inner envelope in 6/7 protostars is further evidence that water must be heavily depleted from the gas-phase at these radii. Infall in four of the sources is supersonic and infall in all sources must take place at the outer edge of the envelope, which may be evidence that collapse is global or outside-in rather than inside-out. The mass infall rate in IRAS4A is large (>~10^-4 msol\yr), higher than the mass outflow rate and expected mass accretion rates onto the star, suggesting that any flattened disk-like structure on small scales will be gravitationally unstable, potentially leading to rotational fragmentation and/or episodic accretion.
The innermost globular clusters of M87

We present a comprehensive multiwavelength photometric analysis of the innermost (∼3 × 3kpc 2 ) 110 globular clusters (GCs) of M87. Their spectral energy distributions (SEDs) were built taking advantage of new ground-based high-resolution near-infrared imaging aided by adaptive optics at the Very Large Telescope combined with Hubble Space Telescope ultraviolet–optical archival data. These GC SEDs are among the best photometrically sampled extragalactic GC SEDs. To compare with our SEDs we constructed equally sampled SEDs of MilkyWayGCs.UsingboththeseMilkyWayclustertemplatesanddifferentstellarpopulation models, ages of >10Gyr and metallicities of [Fe/H] ∼−0.6dex are consistently inferred for the inner GCs of M87. In addition, the metallicity of these GCs is low (�[Fe/H] ∼0.8dex) compared to that of their host galaxy. These results agree with the idea that the GC formation in M87 ceased earlier than that of the bulk of the stars of the central part of the galaxy. The ages of the inner GCs of M87 support the idea that these central parts of the galaxy formed first. Our data do not support evidence of recent wet merging.
The locally adapted patch finite element method for interface problems on triangular meshes

We present a locally adapted parametric finite element method for interface problems. For this adapted finite element method we show optimal convergence for elliptic interface problems with a discontinuous diffusion parameter. The method is based on the adaption of macro elements where a local basis represents the interface. The macro elements are independent of the interface and can be cut by the interface. A macro element which is a triangle in the triangulation is divided into four subtriangles. On these subtriangles, the basis functions of the macro element are interpreted as linear functions. The position of the vertices of these subtriangles is determined by the location of the interface in the case a macro element is cut by the interface. Quadrature is performed on the subtriangles via transformations to a reference element. Due to the locality of the method, its use is well suited on distributed architectures.
The rotational excitation of HCN and HNC by He: new insights on the HCN/HNC abundance ratio in molecular clouds

Modelling of molecular emission from interstellar clouds requires the calculation of rates for excitation by collisions with the most abundant species. The present paper focuses on the calculation of rate coefficients for rotational excitation of the hydrogen cyanide (HCN) and hydrogen isocyanide (HNC) molecules in their ground vibrational state in collision with He. The calculations are based on new two-dimensional potential energy surfaces obtained from highly correlated ab initio calculations. Calculations of pure rotational (de)excitation cross-sections of HCN and HNC by He were performed using the essentially exact close-coupling method. Cross-sections for transitions among the eight first rotational levels of HCN and HNC were calculated for kinetic energies up to 1000 cm−1. These cross-sections were used to determine collisional rate constants for temperatures ranging from 5 to 100 K. A propensity for even Δj transitions is observed in the case of HCN–He collisions whereas a propensity for odd Δj transitions is observed in the case of HNC–He collisions. The consequences for astrophysical models are evaluated and it is shown that the use of HCN rate coefficients to interpret HNC observations can lead to significant inaccuracies in the determination of the HNC abundance, in particular, in cold dark clouds for which the new HNC rates show that the j= 1 − 0 line of this species will be more easily excited by collisions than HCN. An important result of the new HNC–He rates is that the HNC/HCN abundance ratio derived from observations in cold clouds has to be revised from >1 to ≃1, in good agreement with detailed chemical models available in the literature.