cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Propagation of transverse waves in the solar chromosphere probed at different heights with ALMA sub-bands
Creators: name: Gómez, Juan Camilo Guevara
name: Jafarzadeh, Shahin
name: Wedemeyer, Sven
name: Szydlarski, Mikolaj
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The Atacama Large Millimeter/sub-millimeter Array (ALMA) has provided us with an excellent diagnostic tool for studies of the dynamics of the Solar chromosphere, albeit through a single receiver band at one time presently. Each ALMA band consists of four sub-bands that are comprised of several spectral channels. To date, however, the spectral domain has been neglected in favour of ensuring optimal imaging, so that time-series observations have been mostly limited to full-band data products, thereby limiting studies to a single chromospheric layer. Here, we report the first observations of a dynamical event (i.e. wave propagation) for which the ALMA Band 3 data (centred at 3\,mm; 100\,GHz) is split into a lower and an upper sideband. In principle, this approach is aimed at mapping slightly different layers in the Solar atmosphere. The side-band data were reduced together with the Solar ALMA Pipeline (SoAP), resulting in time series of brightness-temperature maps for each side-band. Through a phase analysis of a magnetically quiet region, where purely acoustic waves are expected to dominate, the average height difference between the two side-bands is estimated as $73\pm16$~km. Furthermore, we examined the propagation of transverse waves in small-scale bright structures by means of wavelet phase analysis between oscillations at the two atmospheric heights. We find 6\% of the waves to be standing, while 54\% and 46\% of the remaining waves are propagating upwards and downwards, respectively, with absolute propagating speeds on the order of $\approx96$~km/s, resulting in a mean energy flux of $3800$\,W/m$^2$.
description: 5 pages, 3 figures, Accepted for publication in Astronomy and Astrophysics Letters
Primordial Dusty Rings and Episodic Outbursts in Protoplanetary Discs
Creators: name: Kadam, Kundan
name: Vorobyov, Eduard
name: Basu, Shantanu
Publisher: name: arXiv
Year: 2022
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We investigate the formation and evolution of "primordial" dusty rings occurring in the inner regions of protoplanetary discs, with the help of long-term, coupled dust-gas, magnetohydrodynamic simulations. The simulations are global and start from the collapse phase of the parent cloud core, while the dead zone is calculated via an adaptive $α$ formulation by taking into account the local ionization balance. The evolution of the dusty component includes its growth and back reaction on to the gas. Previously, using simulations with only a gas component, we showed that dynamical rings form at the inner edge of the dead zone. We find that when dust evolution as well as magnetic field evolution in the flux-freezing limit are included, the dusty rings formed are more numerous and span a larger radial extent in the inner disc, while the dead zone is more robust and persists for a much longer time. We show that these dynamical rings concentrate enough dust mass to become streaming unstable, which should result in rapid planetesimal formation even in the embedded phases of the system. The episodic outbursts caused by the magnetorotational instability have significant impact on the evolution of the rings. The outbursts drain the inner disc of grown dust, however, the period between bursts is sufficiently long for the planetesimal growth via streaming instability.The dust mass contained within the rings is large enough to ultimately produce planetary systems with the core accretion scenario. The low mass systems rarely undergo outbursts and thus, the conditions around such stars can be especially conducive for planet formation.
description: 21 pages, 14 figures
Fabry-Perot observations and new models of the HH 47A and HH 47D bow shocks
Creators: name: Cecil, G.
name: Heathcote, S.
name: Morse, J.A.
name: Raymond, J.C.
name: Hartigan, P.
Publisher: name: Institute of Physics Publishing
Year: 1994

description: We present new models for the HH 47 A and HH 47D bow shocks based on line flux and velocity maps obtained with an imaging Fabry-Perot spectrometer. We confirm that HH 47A and HH 47D each show a bow shock/Mach disk morphology, and that velocity variability in the outflow can account for the observed structures. While it was suggested a decade ago that the inner working surface HH 47A appears to be traveling into the wake of HH 47D, we find kinematic evidence that the outer bow shock HH 47D is also not the primary ejection event in the outflow but follows in the wake of previously ejected material. By comparing the observed line ratios and line profiles to those predicted by our bow shock models, we find that both bow shocks have substantially lower shock velocities than their space motions would imply, and that the emission from each bow shock is systematically blueshifted from the rest-frame velocity of the ambient emission, indicating a comoving preshock medium. We derive kinematic ages of ∼1150 yr for HH 47D and ∼550 yr for HH 47A, which implies that the stellar driving source may undergo repetitive eruptions similar to FU Orionis-type outbursts every several hundred years. This timescale is similar to estimates made by Reipurth and collaborators for the separation between major outbursts in the HH 34 and HH 111 stellar jets.
Additional file 3 of Clockwise rotation of SW Japan and timing of Izanagi–Pacific ridge subduction revealed by arc migration
Creators: name: Yamaoka, Ken
name: Wallis, Simon R.
Publisher: name: figshare
Year: 2024
Subjects: subject: Geology
subject: FOS: Earth and related environmental sciences

description: Additional file 3: Table S2 and S3. References.
Attempt to explain black hole spin in X-ray binaries with new physics
Creators: name: Bambi, Cosimo
Publisher: name: arXiv
Year: 2014
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: It is widely believed that the spin of black holes in X-ray binaries is mainly natal. A significant spin-up from accretion is not possible. If the secondary has a low mass, the black hole spin cannot change too much even if the black hole swallows the whole stellar companion. If the secondary has a high mass, its lifetime is too short to transfer the necessary amount of matter and spin the black hole up. However, while black holes formed from the collapse of a massive star with Solar metallicity are expected to have low birth spin, current spin measurements show that some black holes in X-ray binaries are rotating very rapidly. Here I show that, if these objects are not the Kerr black holes of general relativity, the accretion of a small amount of matter ($\sim 2$~$M_\odot$) can make them look like very fast-rotating Kerr black holes. Such a possibility is not in contradiction with any observation and it can explain current spin measurements in a very simple way.
description: 6 pages, 4 figures
Validation of TESS exoplanet candidates orbiting solar analogues in the all-sky PLATO input catalogue
Creators: name: Mantovan, Giacomo
name: Montalto, Marco
name: Piotto, Giampaolo
name: Wilson, Thomas G.
name: Cameron, Andrew Collier
name: Majidi, Fatemeh Zahra
name: Borsato, Luca
name: Granata, Valentina
name: Nascimbeni, Valerio
Publisher: name: arXiv
Year: 2022
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The Transiting Exoplanet Survey Satellite (TESS) is focusing on relatively bright stars and has found thousands of planet candidates. However, mainly because of the low spatial resolution of its cameras ($\approx$ 21 arcsec/pixel), TESS is expected to detect several false positives (FPs); hence, vetting needs to be done. Here, we present a follow-up program of TESS candidates orbiting solar-analogue stars that are in the all-sky PLATO input catalogue. Using Gaia photometry and astrometry we built an absolute colour-magnitude diagram and isolated solar-analogue candidates' hosts. We performed a probabilistic validation of each candidate using the VESPA software and produced a prioritized list of objects that have the highest probability of being genuine transiting planets. Following this procedure, we eliminated the majority of FPs and statistically vetted 23 candidates. For this remaining set, we performed a stellar neighbourhood analysis using Gaia Early Data Release 3 and centroid motion tests, greatly enhancing the on-target probability of 12 of them. We then used publicly available high-resolution imaging data to confirm their transit source and found five new, fully validated planets. For the remaining candidates, we propose on-off photometry to further refine the list of genuine candidates and prepare for the subsequent radial velocity follow-up.
description: 16 pages, 11 figures. Accepted for publication in MNRAS on 2022 August 23
¡Se agranda el equipo!
Creators: name: MetaDocencia Team
Publisher: name: Zenodo
Year: 2023
Subjects: Comunidad
Ciencia Abierta
Latinoamérica
enseñanza
Gobernanza

description: En septiembre incorporamos tres personas al equipo (sí, ¡3!) a partir de una convocatoria para coordinación de proyectos. También comenzamos a trabajar junto a otras comunidades para ampliar la participación en Ciencia Abierta y estamos registrando la contribución de muchas personas con las que colaboramos de manera externa para cumplir nuestra misión y visión.
Nodeless superconductivity in noncentrosymmetric LaRhSn
Creators: name: Nie, Z. Y.
name: Shu, J. W.
name: Wang, A.
name: Su, H.
name: Duan, W. Y.
name: Hillier, A. D.
name: Adroja, D. T.
name: Biswas, P. K.
name: Takabatake, T.
name: Smidman, M.
name: Yuan, H. Q.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The superconducting order parameter of the noncentrosymmetric superconductor LaRhSn is investigated by means of low temperature measurements of the specific heat, muon-spin relaxation/rotation ($μ$SR) and the tunnel-diode oscillator (TDO) based method. The specific heat and magnetic penetration depth [$λ(T)$] show an exponentially activated temperature dependence, demonstrating fully gapped superconductivity in LaRhSn. The temperature dependence of $λ^{-2}(T)$ deduced from the TDO based method and $μ$SR show nearly identical behavior, which can be well described by a single-gap $s$-wave model, with a zero temperature gap value of $Δ(0)=1.77(4)k_BT_c$. The zero-field $μ$SR spectra do not show detectable changes upon cooling below $T_c$, and therefore there is no evidence for time-reversal-symmetry breaking in the superconducting state.
description: 9 pages, 8 figures
Self-Assembling Decentralized Control Constructs for Large-Scale Variably-Interconnected Systems
Creators: name: Ippolito, Corey A.
Publisher: name: Figshare
Year: 2018
Subjects: subject: Computer Engineering
subject: 90699 Electrical and Electronic Engineering not elsewhere classified
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: There is an emerging need to develop new techniques for control system design that better address the challenges posed by modern large-scale cyber-physical systems. These systems are often massive networks of interconnected and interoperating subsystems that fuse physical processes, embedded computation, automation technologies, and communication. The resulting problems are dimensionally large, exhibit significant time-varying structural variations during operation, and feature complex dynamics, constraints and objectives across local and global-system scales. These properties are difficult to address using traditional control theoretic methods without substantial loss of performance and robustness. To overcome these limitations, this dissertation presents new concepts and methods for control of modern large-scale variably-structured systems through self-assembling and self-configuring control constructs that allow for fundamental restructuring of the control system’s topology in response to the current system structure. We present the System Component Graph (SCG) formulation as a mathematical framework that generalizes and extends directed graph methods from decentralized control. We present algorithms, methods, and metrics for real-time decentralization and control-structure optimization, utilizing the inclusion principle for addressing interconnected overlapping dynamics and optimal linear-quadratic (LQ) methods for local decentralized subsystem control. Global system control and performance is achieved through a centralized planner that provides continuous real-time optimized trajectories as guidance command inputs to each subsystem. We present the method of Random Subcomplement Trees (RST) for pseudo-optimal real-time trajectory planning of large-scale systems which formalizes and extends the method of rapidly-exploring random trees in a control optimization framework. The RST method defines transformations from the higher-dimension state space into an intermediate lower-dimensional search space, where optimal transitions between subspace states are defined. In the context of this approach, the resulting decentralized topology found within the SCG framework provides the RST subspace definition and requisite transformations, and optimal transitions in the search space are found through forward evaluation of the closed-loop decentralized subsystem dynamics. The methods developed in this thesis are applied to a set of real-world problems spanning various domains and demonstrate the application of these methods from first-principle modeling through control system analysis, design, implementation, and evaluation in experimental tests and simulation.
Quantum ultra-cold atomtronics
Creators: name: Olsen, M. K.
name: Bradley, A. S.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: It is known that a semi-classical analysis is not always adequate for atomtronics devices, but that a fully quantum analysis is often necessary to make reliable predictions. While small numbers of atoms at a small number of sites are tractable using the density matrix, a fully quantum analysis is often not straightforward as the system becomes larger. We show that the fully quantum positive-P representation is then a viable calculational tool. We postulate an atomtronic phase-gate consisting of four wells in a Bose-Hubbard configuration, for which the semi-classical dynamics are controllable using the phase of the atomic mode in one of the wells. We show that the quantum predictions of the positive-P representation for the performance of this device have little relation to those found semi-classically, and that the performance depends markedly on the actual quantum states of the initially occupied modes. We find that initial coherent states lead to closest to classical dynamics, but that initial Fock states give results that are quite different. A fully quantum analysis also opens the door for deeply quantum atomtronics, in which properties such as entanglement and EPR (Einstein-Podolsky-Rosen) steering become valuable technical properties of a device.
description: 12 pages, 6 figures, submitted to Phys. Rev A
Observations of entrainment and time variability in the HH 47 jet
Creators: name: Heathcote, S.
name: Cecil, G.
name: Hartigan, P.
name: Morse, J.A.
Publisher: name: Institute of Physics Publishing
Year: 1993

description: We present new Fabry-Perot images of the HH 47 jet that show the first clear evidence for entrainment in a jet from a young star. The material in the jet moves faster down the axis of the flow and slower at the edges, similar to viscous flow in a pipe. The higher excitation lines occur along the edges of the jet, as expected if entrainment accelerates and heats the ambient material. We confirm previous observations of multiple bow shocks in this system. Together, time variability and entrainment produce much of the observed shock-excited gas in this object. Our data show that the "wiggles" along the jet are not caused by jet material tied to a spiraling magnetic field, but instead result from time variability, variable ejection angles, or inhomogeneities in the flow. The gas entrained in the HH 47 jet may be atomic; our results do not provide direct evidence that stellar jets drive molecular outflows.
Periodic Clifford symmetry algebras on flux lattices
Creators: name: Huang, Yue-Xin
name: Chen, Z. Y.
name: Feng, Xiaolong
name: Yang, Shengyuan A.
name: Zhao, Y. X.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Real Clifford algebras play a fundamental role in the eight real Altland-Zirnbauer symmetry classes and the classification tables of topological phases. Here, we present another elegant realization of real Clifford algebras in the $d$-dimensional spinless rectangular lattices with $π$ flux per plaquette. Due to the $T$-invariant flux configuration, real Clifford algebras are realized as projective symmetry algebras of lattice symmetries. Remarkably, $d$ mod $8$ exactly corresponds to the eight Morita equivalence classes of real Clifford algebras with eightfold Bott periodicity, resembling the eight real Altland-Zirnbauer classes. The representation theory of Clifford algebras determines the degree of degeneracy of band structures, both at generic $k$ points and at high-symmetry points of the Brillouin zone. Particularly, we demonstrate that the large degeneracy at high-symmetry points offers a rich resource for forming novel topological states by various dimerization patterns, including a $3$D higher-order semimetal state with double-charged bulk nodal loops and hinge modes, a $4$D nodal surface semimetal with $3$D surface solid-ball zero modes, and $4$D Möbius topological insulators with a eightfold surface nodal point or a fourfold surface nodal ring. Our theory can be experimentally realized in artificial crystals by their engineerable $\mathbb{Z}_2$ gauge fields and capability to simulate higher dimensional systems.
description: 8 pages, 6 figures
The Effect of Information Limitations on Information Usage of Tehrani Youth Users
Publisher: name: Iranian Research Institute for Information Science and Technology (IranDoc)
Year: 2018

description: This research tries to study the effect of information limitation on the users’ tendency toward using Internet information amongst adolescents and youth in Tehran. After reviewing research theoretical and practical literature, using internet has been defined as using it for gathering information for task and professional purposes like scientific use and news reading. Theoretical explanation of the information limitation effect on users’ tendency has been possible based on sociological and communication theories. In relationship between two mentioned variables, two moderator variables – social and economical status and use experience- has been studied .The research method is survey and research data has been gathered using questionnaire. Our population is 15 to 29 years old adolescents and youth in Tehran. Assessing data gathered from 384 respondents show that adolescents and youth have average tendency toward information using. Hypothesis testing shows that information limitation has a negatively significant correlation with users’ attitude. Based on the research, users’ experience and social and economical status don’t have a significant correlation with the information limitation effect on the users’ tendency.
Problems in Discrete Geometry and Extremal Combinatorics
Creators: name: Zilin  Jiang
Publisher: name: Figshare
Year: 2018
Subjects: subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics

description: We study several problems in discrete geometry and extremal combinatorics. Discrete geometry studies the combinatorial properties of finite sets of simple geometric objects. One theme of the field is geometric Ramsey theory. Given m geometric objects, we want to select a not too small subset forming a configuration that is “regular” in some sense.
Additional complex conjugate feedback induced explosive death and multistabilities
Creators: name: Sathiyadevi, K.
name: Premraj, D.
name: Banerjee, Tanmoy
name: Lakshmanan, M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: Many natural and man-made systems require suitable feedback to function properly. In this study, we aim to investigate the impact of additional complex conjugate feedback on globally coupled Stuart-Landau oscillators. We find that this additional feedback results in the onset of symmetry breaking clusters and out-of-phase clusters. Interestingly, we also find the existence of explosive amplitude death along with disparate multistable states. We characterize the first-order transition to explosive death through the amplitude order parameter and show that the transition from oscillatory to death state indeed shows a hysteresis nature. Further, we map the global dynamical transitions in the parametric spaces. In addition, to understand the existence of multistabilities and their transitions, we analyze the bifurcation scenarios of the reduced model and also explore their basin stability. Our study will shed light on the emergent dynamics in the presence of additional feedback.
description: 8 pages, 7 figures, Accepted for publication in Phys. Rev. E
Dust processing in protoplanetary envelopes as the origin of hot minerals in comets
Creators: name: Ali-Dib, Mohamad
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Crystalline silicates are found in a large number of comets. These pose a long-standing conundrum for solar system formation models as they can only be created in the inner hot disk at temperatures higher than 800 K, and there is no obvious mechanism to transport them out into the comets formation region. Here we propose that these particles could have formed inside the hydrostatic envelopes surrounding young protoplanets still embedded in the protoplanetary disk. Using a simplified 1D model we investigate the thermal structure of these envelopes, and find that for core masses ranging from 0.08 to 1.5 M_Earth, located anywhere between 1 and 30 AU, the temperature and pressure at the base of the envelopes are high enough to quickly vaporize silicate particles of various sizes. Moreover, if the grain abundance is at least solar, these envelopes become fully convective, allowing for dust ejection across the Bondi radius back into the disk. Amorphous silicates are hence thermally processed into crystalline particles in these envelopes, and then transported back to disk through convective diffusion to be finally incorporated into the cometary building blocks.
description: Accepted for publication in MNRAS. 4 pages, 2 figures
On the Complexity of Immersed Normal Surfaces
Creators: name: Burton, Benjamin A.
name: de Verdière, Éric Colin
name: de Mesmay, Arnaud
Publisher: name: arXiv
Year: 2014
Subjects: subject: Geometric Topology (math.GT)
subject: Computational Geometry (cs.CG)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: 68U05, 57M50, 68Q25

description: Normal surface theory, a tool to represent surfaces in a triangulated 3-manifold combinatorially, is ubiquitous in computational 3-manifold theory. In this paper, we investigate a relaxed notion of normal surfaces where we remove the quadrilateral conditions. This yields normal surfaces that are no longer embedded. We prove that it is NP-hard to decide whether such a surface is immersed. Our proof uses a reduction from Boolean constraint satisfaction problems where every variable appears in at most two clauses, using a classification theorem of Feder. We also investigate variants, and provide a polynomial-time algorithm to test for a local version of this problem.
description: 17 pages, under journal submission
Multiple locations of near-infrared coronal lines in NGC 5548
Creators: name: Kynoch, Daniel
name: Landt, Hermine
name: Dehghanian, Maryam
name: Ward, Martin J.
name: Ferland, Gary J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present the first intensive study of the variability of the near-infrared coronal lines in an active galactic nucleus (AGN). We use data from a one-year long spectroscopic monitoring campaign with roughly weekly cadence on NGC 5548 to study the variability in both emission line fluxes and profile shapes. We find that in common with many AGN coronal lines, those studied here are both broader than the low-ionisaton forbidden lines and blueshifted relative to them, with a stratification that implies an origin in an outflow interior to the standard narrow line region. We observe for the first time [S VIII] and [Si VI] coronal line profiles that exhibit broad wings in addition to narrow cores, features not seen in either [S IX] or [Si X]. These wings are highly variable, whereas the cores show negligible changes. The differences in both the profile shapes and variability properties of the different line components indicate that there are at least two coronal line regions in AGN. We associate the variable, broad wings with the base of an X-ray heated wind evaporated from the inner edge of the dusty torus. The coronal line cores may be formed at several locations interior to the narrow line region: either along this accelerating, clumpy wind or in the much more compact outflow identified with the obscurer and so emerging on scales similar to the outer accretion disc and broad line region.
description: 20 pages, 16 figures and 6 tables. Accepted for publication in MNRAS
Rheology, Diffusion and Plastic Correlations in Jammed Suspensions
Creators: name: Arka Prabha Roy
Publisher: name: Figshare
Year: 2018
Subjects: subject: 90799 Environmental Engineering not elsewhere classified
subject: FOS: Environmental engineering
subject: 90599 Civil Engineering not elsewhere classified
subject: FOS: Civil engineering

description: We present results using Durian's bubble model [1] to study the spatio- temporal correlations and rheological response to imposed shear ow in steady state in jammed suspensions of soft, frictionless disks. We firrst study the so- called mean drag (MD) variant of the model which is appropriate for modeling particles at interfaces where the dominant dissipation comes from motion of the particle with respect to the phases o  the interface.
The bow shock and mach disk of HH 111V
Creators: name: Hartigan, P.
name: Raymond, J.C.
name: Heathcote, S.
name: Cecil, G.
name: Morse, J.A.
Publisher: name: Institute of Physics Publishing
Year: 1993

description: We present spatially resolved line profiles in Hα and [S II] λλ16716, 6731 across the working surface region in the Herbig-Haro object HH 111V. Data were acquired with the Rutgers/CTIO imaging Fabry-Perot interferometer on the CTIO 4 m telescope at ∼1″.3 FWHM spatial and ∼35 km s-1 FWHM kinetic resolution. We separate Mach disk emission spatially and kinematically from the bow shock emission. We have used the Hα flux measured at the apex of the bow shock to estimate the preshock density of ∼200 cm-3. Our detailed measurements of the electron density as a function of position and velocity across the bow shock, combined with new models of the bow shock emission, show that an ambient magnetic field of ∼30 μG inhibits the compression of the postshock gas. Our models indicate that the magnetic field also contributes to extending the cooling distance behind the shock to resolvable scales, as observed in the spatial separation of [S II] and Hα in the emission-line images of Reipurth et al. However, the ram pressure at the bow shock HH 111V exceeds the magnetic energy density by a factor of ∼103, so the magnetic field is not large enough to change the direction of the flow. The preshock medium must flow away from the stellar energy source at ∼300 km s-1 to account for the observed kinematics of the line emission in HH 111V. Hence, this working surface is a secondary ejection moving into the wake of an earlier ejection. HH 111 is the third case (HH 34 and HH 47 are other examples) of a stellar jet where the brightest bow shock moves into the wake of a previous high-velocity ejection. Balancing the ram pressures in the bow shock and Mach disk yields an estimated jet-to-ambient density ratio ∼10, similar to our previous estimate for the HH 34 jet (Morse et al.).
Runtime Monitoring for Safety-Critical Embedded Systems
Creators: name: Kane, Aaron
Publisher: name: Figshare
Year: 2018
Subjects: subject: Computer Engineering
subject: 90699 Electrical and Electronic Engineering not elsewhere classified
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: The trend towards more commercial-off-the-shelf (COTS) components in complex safety-critical systems is increasing the difficulty of verifying system correctness. Runtime verification (RV) is a lightweight technique to verify that certain properties hold over execution traces. RV is usually implemented as runtime monitors that can be used as runtime fault detectors or test oracles to analyze a system under test for bad behaviors. Most existing RV methods utilize some form of system or code instrumentation and thus are not designed to monitor potentially black-box COTS components. This thesis presents a suitable runtime monitoring framework for monitoring safety-critical embedded systems with black-box components. We provide an end-to-end framework including proven correct monitoring algorithms, a formal specification language with semi-formal techniques to map the system onto our formal system trace model, specification design patterns to aid translating informal specifications into the formal specification language, and a safety-case pattern example showing the argument that our monitor design can be safely integrated with a target system. We utilized our monitor implementation to check test logs from several system tests. We show the monitor being used to check system test logs offline for interesting properties. We also performed real-time replay of logs from a system network bus, demonstrating the feasibility of our embedded monitor implementation in real-time operation.
Influence of isolated and clustered defects on electronic and dielectric properties of wustite
Creators: name: Wdowik, Urszula D.
name: Piekarz, Przemyslaw
name: Jochym, Pawel T.
name: Parlinski, Krzysztof
name: Oles, Andrzej M.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The influence of intrinsic Fe defects in FeO (either single cation vacancies or prototypical 4:1 vacancy clusters) on the electronic and dielectric properties is studied within the density functional theory. The importance of local Coulomb interactions at Fe atoms is highlighted and shown to be responsible for the observed insulating Mott gap in FeO which is reduced by the presence of defects. We investigate nonstoichiometric configurations of Fe1-xO with x ranging from 3 to 9 % and find the aliovalent Fe cations in both the regular and interstitial lattice sites of the considered configurations. Furthermore, we show that the trivalent Fe ions are induced by both isolated and clustered Fe-vacancies and introduce the empty band states inside the insulating gap, which decreases monotonically with increasing cation vacancy concentration. The Fe1-xO systems with high defect content become metallic for small values of the Coulomb interaction U, yielding the increase in the dielectric functions and optical reflectivity at low energies in agreement with the experimental data. Due to the crystal defects, the infrared-active transverse optic phonons split and distribute over a wide range of frequencies clarifying the origin of the exceptionally large spectral linewidths of the dielectric loss functions observed for wustite in recent experiments.
description: 11 page, 8 figures
Spectrophotometric evidence for velocity variability in the HH 34 and HH 111 stellar jets
Creators: name: Hartigan, P.
name: Cecil, G.
name: Heathcote, S.
name: Morse, J.A.
Publisher: name: University of Chicago Press
Year: 1993

description: We present Fabry-Perot observations and long-slit spectrophotometry of the collimated jet regions of the HH 34 and HH 111 outflows. There is a close correlation between the observed [S II] flux and the electron density in the bright low-excitation knots in both the HH 34 jet and the HH 111 jet. The electron densities in some of the low-excitation HH 111 jet knots exceed 2500 cm-3, from which we infer that the true gas densities may be significantly higher than ∼104 cm-3 because the peak ionization is only a few percent for such weak shocks. We detect weak [O III]λ5007 emission from the HH 111 jet knot L, which implies that the shock velocity for this knot is ∼100 km s-1. This knot also has a large velocity dispersion (∼200 km s-1) and bow-shaped morphology {Reipurth et al. [ApJ, 392, 145 (1992)]}. We argue that such a feature cannot be explained by models in which knots correspond to internal shock waves excited by boundary layer instabilities, but is consistent with an internal working surface in a velocity-variable outflow. We review evidence for multiple ejections in each of these stellar jets.
Period-Colour and Amplitude-Colour relations for OGLE-$δ$ Scuti stars in the Galactic Bulge and LMC
Creators: name: Deka, Mami
name: Kanbur, Shashi M.
name: Deb, Sukanta
name: Das, Susmita
name: Kurbah, Kerdaris
name: Bellinger, Earl P.
name: Bhardwaj, Anupam
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present an analysis on the behaviour of the Galactic bulge and the Large Magellanic Cloud (LMC) $δ$ Scuti stars in terms of period-colour and amplitude-colour (PCAC) relations at maximum, mean and minimum light. The publicly available Optical Gravitational Lensing Experiment-IV (OGLE-IV) light curves for Galactic bulge and OGLE-III light curves for LMC $δ$ Scuti stars are exploited for the analysis. It has been found that the Galactic bulge $δ$ Scuti stars obey flat PC relations at maximum/mean/minimum light while the LMC $δ$ Scutis have sloped/sloped/flat PC relations at maximum/mean/minimum light. Both the Galactic bulge and the LMC $δ$ Scutis have sloped/flat/sloped AC relations at maximum/mean/minimum. These relations also show that Galactic $δ$ Scutis are hotter as compared to their LMC counterparts. The period-amplitude (PA) relations for $δ$ Scutis exhibit different behaviour in the Galactic bulge and the LMC. The LMC variables are found to have higher amplitudes at a given period. The amplitude of the Galactic bulge $δ$ Scuti shows a bimodal distribution which can be modelled using a two-component Gaussian Mixture Model: one component with a lower amplitude and another with a higher amplitude. The observed behaviour of the $δ$ Scuti PCAC relations can be explained using the theory of the interaction of hydrogen ionization front (HIF) and stellar photosphere as well as the PA diagram. We use MESA-RSP to calculate theoretical non-linear hydrodynamical pulsation models for $δ$ Scuti stars with input metallicities of $Z=0.02$ and $Z=0.008$ appropriate for the Galactic bulge and LMC, respectively. The observed PCAC relations and theoretical calculations support the HIF-photosphere interaction theory.
description: 12 pages, 8 figures, accepted in MNRAS
Molecular Fraction in the Galactic Center: The Central Molecular and HI Zones
Creators: name: Sofue, Yoshiaki
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: By mapping the molecular fraction of the Galactic Center (GC), we quantitatively address the question of how much molecular and central the CMZ (Central Molecular Zone) is. For this purpose we analyze the CO and HI-line archival data, and determine the column- (surface-) and volume-molecular fractions, $f_{\rm mol}^Σ$ and $f_{\rm mol}^ρ$, which are the ratio of column-mass density of H$_2$ projected on the sky to that of total gas (H$_2$ + HI) from the line intensities, and the ratio of volume-mass densities of \Htwo\ to total gas from the brightness temperature, respectively. It is shown that $f_{\rm mol}^Σ$ is as high as $ \sim 0.9-0.95$ in the CMZ, and $f_{\rm mol}^ρ$ is $0.93-0.98$ in the GC Arms I and II attaining the highest value of $\sim 0.98$ toward Sgr B2. The expanding molecular ring (EMR, or the parallelogram) has a slightly smaller $f_{\rm mol}^Σ$ as $\sim 0.9-0.93$. We define the CMZ as the region with $f_{\rm mol}^Σ\ge 0.8-0.9$ between the shoulders of plateau-like distribution of H$_2$ column density from $l=-1^\circ.1$ to $+1^\circ.8$ having Gaussian vertical distribution with a half thickness of $\pm 0^\circ.2$. The CMZ is embedded in the Central HI Zone (CHZ), which is defined as an HI disc between $l\sim -2^\circ$ and $+2^\circ.5$, $b=-0^\circ.5$ and $+0^\circ.5$. Based on the analysis, we discuss the origin of CMZ and interstellar physics such as the volume filling factors of molecular and HI gases inferred from the difference between $ f_{\rm mol}^Σ$ and $f_{\rm mol}^ρ$.
description: Accepted for MNRAS, 14 pages, 12 figures
Additional file 1 of Modelling TDP-43 proteinopathy in Drosophila uncovers shared and neuron-specific targets across ALS and FTD relevant circuits
Creators: name: Godfrey, R. Keating
name: Alsop, Eric
name: Bjork, Reed T.
name: Chauhan, Brijesh S.
name: Ruvalcaba, Hillary C.
name: Antone, Jerry
name: Gittings, Lauren M.
name: Michael, Allison F.
name: Williams, Christi
name: Hala’ufia, Grace
name: Blythe, Alexander D.
name: Hall, Megan
name: Sattler, Rita
name: Van Keuren-Jensen, Kendall
name: Zarnescu, Daniela C.
Publisher: name: figshare
Year: 2024
Subjects: subject: Genetics
subject: FOS: Biological sciences

description: Additional file 1: Figure 1-supplement 1. Maximum intensity projections showing split Gal4 driver line SS01276 expression in the 3rd instar larva. Figure 1-supplement 2. TDP-43G298S localization in MBN cell bodies. Figure 1-supplement 3. Method for measuring the ratio of nucleus to total cell TDP-43 YFP from mean pixel intensity of MBNs. Figure 2-supplement 1. Mushroom body lobes (MBLs) show age-related, region-specific TDP-43G298S cytoplasmic accumulation and axonal fragmentation. Figure 4-supplement 1. TDP-43G298S overexpression in MBNs reduces arousal, increasing day and night sleep. Figure 5-supplement 1. Mutant TDP-43 overexpression in MBNs is sufficient to reduce lifespan. Figure 6-supplement 1. mRNAs enriched with TDP-43G298S overexpression in Drosophila MBs. Figure 6-supplement 2. Functional annotation of enriched targets in fly models of TDP-43 driven dementia. Figure 7-supplement 1. Dally-like protein is a target of TDP-43G298S in MBNs. Figure 7-supplement 2. TDP-43WT protein expression is not reduced by the presence of a second UAS-driven transgene. Figure 7-supplement 3. TDP-43WT YFP expression levels is not reduced by concomitant expression of a second UAS-driven transgene (mCD8 RFP).
Lessons Learned Applying Deep Learning Approaches to Forecasting Complex Seasonal Behavior
Creators: name: Karl, Andrew T.
name: Wisnowski, James
name: Petropoulos, Lambros
Publisher: name: arXiv
Year: 2023
Subjects: subject: Applications (stat.AP)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Deep learning methods have gained popularity in recent years through the media and the relative ease of implementation through open source packages such as Keras. We investigate the applicability of popular recurrent neural networks in forecasting call center volumes at a large financial services company. These series are highly complex with seasonal patterns - between hours of the day, day of the week, and time of the year - in addition to autocorrelation between individual observations. Though we investigate the financial services industry, the recommendations for modeling cyclical nonlinear behavior generalize across all sectors. We explore the optimization of parameter settings and convergence criteria for Elman (simple), Long Short-Term Memory (LTSM), and Gated Recurrent Unit (GRU) RNNs from a practical point of view. A designed experiment using actual call center data across many different "skills" (income call streams) compares performance measured by validation error rates of the best observed RNN configurations against other modern and classical forecasting techniques. We summarize the utility of and considerations required for using deep learning methods in forecasting.
description: Published in 2019 Joint Statistical Meetings (JSM) proceedings
Shape For Contact
Creators: name: Garcia, Alberto Rodriguez
Publisher: name: Figshare
Year: 2018
Subjects: subject: 80101 Adaptive Agents and Intelligent Robotics
subject: FOS: Computer and information sciences

description: Given a desired function for an effector, what is its appropriate shape? This thesis addresses the problem of designing the shape of a rigid end effector to perform a given manipulation task. It presents three main contributions: First, it describes the contact kinematics of an effector as the product of both its shape and its motion, and assumes a fixed motion model to explore the role of shape in satisfying a certain manipulation task. Second, it formulates that manipulation task as a set of constraints on the geometry of contact between the effector and the world. Third, it develops tools to transform those contact constraints into an effector shape for general 1-DOF planar mechanisms and general 1-DOF spatial mechanisms, and discusses the generalization to mechanisms with more than one degree of freedom.
We describe the case studies of designing grippers with invariant grasp geometry, grippers with improved grasp stability, and grippers with extended grasp versatility. We further showcase the techniques with the design of the fingers of the MLab hand, a three-fingered gripper actuated with a single motor, capable of exerting any combination of geometrically correct enveloping or fingertip grasps of spherical, cylindrical, and prismatic objects of varying size.
Probing the galaxy-halo connection in UltraVISTA to $z\sim2$
Creators: name: McCracken, H. J.
name: Wolk, M.
name: Colombi, S.
name: Kilbinger, M.
name: Ilbert, O.
name: Peirani, S.
name: Coupon, J.
name: Dunlop, J.
name: Milvang-Jensen, B.
name: Caputi, K.
name: Aussel, H.
name: Béthermin, M.
name: Fèvre, O. Le
Publisher: name: arXiv
Year: 2014
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We use percent-level precision photometric redshifts in the UltraVISTA-DR1 near-infrared survey to investigate the changing relationship be- tween galaxy stellar mass and the dark matter haloes hosting them to $z\sim2$. We achieve this by measuring the clustering properties and abundances of a series of volume-limited galaxy samples selected by stellar mass and star-formation activity. We interpret these results in the framework of a phenomenological halo model and numerical simulations. Our measurements span a uniquely large range in stellar mass and redshift and reach below the characteristic stellar mass to $z\sim2$. Our results are: 1. At fixed redshift and scale, clustering amplitude depends monotonically on sample stellar mass threshold; 2. At fixed angular scale, the projected clustering amplitude decreases with redshift but the co-moving correlation length remains constant; 3. Characteristic halo masses and galaxy bias increase with increasing median stellar mass of the sample; 4. The slope of these relationships is modified in lower mass haloes; 5. Concerning the passive galaxy population, characteristic halo masses are consistent with a simply less-abundant version of the full galaxy sample, but at lower redshifts the fraction of satellite galaxies in the passive population is very different from the full galaxy sample; 6. Finally we find that the ratio between the characteristic halo mass and median stellar mass at each redshift bin reaches a peak at ${\log(M_h/M_\odot)}\sim12.2$ and the position of this peak remains constant out to $z\sim2$. The behaviour of the full and passively evolving galaxy samples can be understood qualitatively by considering the slow evolution of the characteristic stellar mass in the redshift range probed by our survey.
description: 18 pages, 14 figures; submitted to MNRAS. Comments are welcome
EMPIR 19ENG06 HEFMAG Extended comparisons of total power loss measurements performed by an SST using revised measurement procedures at room temperature - Extended final report
Creators: name: Ulvr, Michal
Publisher: name: Zenodo
Year: 2023

description: D1c: Extended final report about round robin comparison of total power loss measurements performed by SST at 50 Hz and 100 Hz including NIM China and stakeholders.
The braided jets in the spiral galaxy NGC 4258
Creators: name: Wilson, A.S.
name: Cecil, G.
name: Tully, R.B.
Publisher: name: Institute of Physics Publishing
Year: 1992

description: We have used the Hawaii Imaging Fabry-Perot Interferometer to synthesize 44,000 Hα and [N II] emission-line profiles at velocity resolution 68 km s-1 FWHM across the disk of the nearby Seyfert/LINER galaxy NGC 4258, including the prominent "four-branched jet" that extends to 10 and 5 kpc radii in the radio continuum and optical emission lines, respectively. A long-slit spectrum, which includes the emission lines Hα, [N II] λλ6548, 6583 and [S II] λλ6717, 6731, has also been obtained along the jets. These data are used for a comprehensive kinematic study of the galaxy. The disk velocity field is best fitted with a model that incorporates elliptical, bar-forced streaming motions, as suggested by the H I and CO kinematics. Velocity dispersions along the SE jet average 80 km s-1, compared to 40 km s-1 in the H II regions. This broadening arises from a helical, braided structure of three intertwined plasma streams, as inferred from both the spatial and kinematic structure of the jet. The emission-line profiles split into two distinct velocity systems with separations 300 ± 30 km s-1 within 1.7 kpc of the nucleus along the midaxis of the braid pattern. Gaussian decomposition of the line profiles show that the internal velocity dispersion of each helical strand is ≈100 km s-1. We observe two cycles of the triple-braid pattern, with wavelength ≈1.4 kpc and side-to-side amplitude ≈400 pc. If the braided streams represent ballistic motion of gas ejected from orbiting objects, the outflow velocity is ≈2000 km s-1. The masses and separations of the compact objects would be ≈3 × 106 M⊙ and ≈6 pc (0″.2), respectively. However, the emission-line velocity field of the SE jet suggests that the gas moves along the helices, perhaps as a result of fluid instabilities at the interface between the jet and the interstellar medium or of motion along magnetic flux tubes. We show that the NNW jet follows a clear channel between molecular cloud complexes, and exhibits several emission-line "hot spots" and bends where it interacts with the surrounding molecular gas. High-velocity gas in the SE and NW radio "plateaus" probably results from earlier ejections of gas from the nucleus in these directions, with the jet nozzle having precessed to its present orientation. We find that the jets have total ionized mass 1.5 × 106 M⊙ (1 cm-3/ne) and [N II] λ6583/Hα ratios consistent with shock excita-tion. An Einstein HRI image reveals X-ray emission from the nucleus and SE jet. We show that the jet's X-ray emission may be interpreted as thermal bremsstrahlung from hot, shocked jet gas.