cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Goldstone Twin Telescope Tests: Tying Antennas at the mm level
Creators: name: Jacobs, Christopher S.
Publisher: name: Zenodo
Year: 2023
Subjects: VLBI
Deep Space Network
Goldstone
X-band
station tie

description: Each of NASA”s three Deep Space Network (DSN) sites has multiple large antennas capable of acquiring VLBI data. The long range plan is to have four 34-meter antennas at each site. At present Goldstone has three; with another under construction. These antennas offer the opportunity to do connected element interferometry (CEI) over the few hundred meter baselines within each complex. Given that all antennas within a site are of nominally the same structural design, are run off the same clock, observe through almost the same atmosphere, and are subject to almost the same geophysics, doing CEI experiments is an excellent way to probe the limits of VLBI accuracy and expose station specific systematic errors. This paper will report on results from the Goldstone California complex over 2016 to 2023 which achieved a per pass baseline precision of about 0.2 mm horizontal and 1 mm in the vertical. There is evidence for 1 mm level systematics. Based on this data we will discuss the implications for whether the IAG’s goal of 1mm station stability in VLBI geodesy is possible for large DSN antennas.
description: Copyright © 2023, All Rights Reserved. This research was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).
description: {"references": ["U.S. Geological Survey, map of 2019 Ridgecreast quake"]}
Additional file 1 of Sero-epidemiology and associated factors of HIV, HBV, HCV and syphilis among blood donors in Ethiopia: a systematic review and meta-analysis
Creators: name: Melku, Mulugeta
name: Ambachew, Sintayehu
name: Enawgaw, Bamlaku
name: Abebe, Molla
name: Abebe, Zegeye
name: Deressa, Tekalign
name: Damtie, Debasu
name: Biadgo, Belete
name: Tessema, Belay
name: Geremew, Demeke
name: Kebede, Asemarie
name: Woldu, Berhanu
name: Teklu, Takele
name: Shiferaw, Elias
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Science Policy
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: 60506 Virology
subject: FOS: Biological sciences

description: Additional file 1: Table S1. PRISMA 2009 checklist.
X-ray luminosity functions of different morphological and X-ray type AGN populations
Creators: name: Pović, M.
name: García, A. M. Pérez
name: Sánchez-Portal, M.
name: Bongiovanni, A.
name: Cepa, J.
name: Lorenzo, M. Fernández
name: Lara-López, M. A.
name: Gallego, J.
name: Ederoclite, A.
name: Márquez, I.
name: Masegosa, J.
name: Alfaro, E.
name: Castañeda, H.
name: González-Serrano, J. I.
name: González, J. J.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Luminosity functions are one of the most important observational clues when studying galaxy evolution over cosmic time. In this paper we present the X-ray luminosity functions of X-ray detected AGN in the SXDS and GWS fields. The limiting fluxes of our samples are 9.0x10^(-15) and 4.8x10^(-16) erg/cm^2/sec^(-1) in the 0.5 - 7.0 keV band in the two fields, respectively. We carried out analysis in three X-ray bands and in two redshift intervals up to z < 1.4. Moreover, we derive the luminosity functions for different optical morphologies and X-ray types. We confirm strong luminosity evolution in all three bands, finding the most luminous objects at higher redshift. However, no signs of density evolution are found in any tested X-ray band. We obtain similar results for compact and early-type objects. Finally, we observe the `Steffen effect', where X-ray type-1 sources are more numerous at higher luminosities in comparison with type-2 sources.
description: published in AN, 12 pages, 8 figures
Geology of a part of the Rosamond Hills area, Kern County, California
Creators: name: Roberts, William B.
Publisher: name: California Institute of Technology
Year: 1951
Subjects: subject: Rosamond Hills
subject: alluvium
subject: Willow Springs Fault
subject: Geology
subject: FOS: Earth and related environmental sciences
subject: Rosamond Lake

description: An erosion surface of low relief was developed on the
granitic complex of the Rosamond Hills area during the
early part of the Tertiary period.  Sometime during the
Miocene epoch, faulting and volcanic activity formed a
series of shallow lakes in which pyroclastic debris accumulated to a maximum depth of 900 feet to form the lower
part of the Rosamond series.  Deformation and volcanic
activity culminated with the elevation of a mountain range
of considerable relief, the outpouring of a comparatively
large amount of rhyolite, and the ejection of much pyroclastic debris.  A series of alluvial fans or bajada de
posits with inercalated layers of pyroclastic debris accumulated along the margin of this mountain range to a
maximum thickness of about 500 feet to form the upper part
of the Rosamond series.  The area was subsequently tilted
southward, and erosion removed the Rosamond series from
the tilted block except for a narrow strip along its sou
thern margin.  Hillocks formed by erosion of this strip of
Rosamond rocks constitute the Rosamond Hills.  Recent
faulting along the southern margin of the Hills has probably
helped to form Rosamond Lake.
Distributed Overlay Anycast Table using Space filling curves
Creators: name: Mykoniati, Eleni
name: Latif, Laurence
name: Landa, Raul
name: Yang, Ben
name: Clegg, Richard G.
name: Griffin, David
name: Rio, Miguel
Publisher: name: arXiv
Year: 2013
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: In this paper we present the \emph{Distributed Overlay Anycast Table}, a structured overlay that implements application-layer anycast, allowing the discovery of the closest host that is a member of a given group. One application is in locality-aware peer-to-peer networks, where peers need to discover low-latency peers participating in the distribution of a particular file or stream. The DOAT makes use of network delay coordinates and a space filling curve to achieve locality-aware routing across the overlay, and Bloom filters to aggregate group identifiers. The solution is designed to optimise both accuracy and query time, which are essential for real-time applications. We simulated DOAT using both random and realistic node distributions. The results show that accuracy is high and query time is low.
description: 7 pages, 4 figures
On the consideration of frequency-dependent illumination functions in modelling signal path variations
Creators: name: Lösler, Michael
name: Kronschnabl, Gerhard
name: Plötz, Christian
name: Neidhardt, Alexander
name: Eschelbach, Cornelia
Publisher: name: Zenodo
Year: 2023
Subjects: Illumination function
Radio telescope
Signal path variation
Deformation
VLBI
VGOS

description: Investigations on the deformation behaviour of the receiving unit of large radio telescopes used for Very Long Baseline Interferometry (VLBI) indicate several elevation-dependent deformation patterns. These include, for instance, elevation-dependent deformations of the main reflector dish, variations in the position of the sub-reflector or the main reflector, or tilts of the sub-reflector. The deformation of the receiving unit yields signal path variations and, if unconsidered, distorts the vertical station position and, hence, the scale of the obtained global geodetic reference frame. Signal path variations result from a weighted combination of the overlapping deformation patterns. The corresponding weights are obtained by the intrinsic illumination function of the radio telescope. The gain of the feed horn and, thus, the illumination of the aperture depends on the frequency. In contrast to legacy radio telescopes, which observe in X-band at about 8.4 GHz, the new generation of radio telescopes participating in the VLBI Global Observing System (VGOS) is designed for broadband reception between 2 GHz and 14 GHz having corresponding illumination functions. This contribution investigates the impact of frequency-dependent illumination functions on signal path variations for the first time. For that purpose, several data-sets obtained from different feed-horns are analysed, and the impact on the signal path variations is studied.
Additional file 2 of Sero-epidemiology and associated factors of HIV, HBV, HCV and syphilis among blood donors in Ethiopia: a systematic review and meta-analysis
Creators: name: Melku, Mulugeta
name: Ambachew, Sintayehu
name: Enawgaw, Bamlaku
name: Abebe, Molla
name: Abebe, Zegeye
name: Deressa, Tekalign
name: Damtie, Debasu
name: Biadgo, Belete
name: Tessema, Belay
name: Geremew, Demeke
name: Kebede, Asemarie
name: Woldu, Berhanu
name: Teklu, Takele
name: Shiferaw, Elias
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Science Policy
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: 60506 Virology
subject: FOS: Biological sciences

description: Additional file 2: Figure S2. A Plot of Egger’s test of publication bias for pooled estimate of HIV among Blood donors in Ethiopia.
Additional file 3 of Sero-epidemiology and associated factors of HIV, HBV, HCV and syphilis among blood donors in Ethiopia: a systematic review and meta-analysis
Creators: name: Melku, Mulugeta
name: Ambachew, Sintayehu
name: Enawgaw, Bamlaku
name: Abebe, Molla
name: Abebe, Zegeye
name: Deressa, Tekalign
name: Damtie, Debasu
name: Biadgo, Belete
name: Tessema, Belay
name: Geremew, Demeke
name: Kebede, Asemarie
name: Woldu, Berhanu
name: Teklu, Takele
name: Shiferaw, Elias
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Science Policy
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: 60506 Virology
subject: FOS: Biological sciences

description: Additional file 3: Figure S3. A Plot of Egger’s test of publication bias for pooled estimate of HBV among Blood donors in Ethiopia.
The X/Ka-band (8.4/32 GHz) 2023a Celestial Reference Frame
Creators: name: Jacobs, Christopher
name: Horiuchi, Shinji
name: Firre, Daniel
name: Murata, Yasuhiro
name: Takeuchi, Hiroshi
name: Uchimura, Takashi
Publisher: name: Zenodo
Year: 2023
Subjects: VLBI
ICRF
Celestial Frame
Ka-band
astrometry
32 GHz
Deep Space Network
NASA
ESA
JAXA

description: The X/Ka-band (8.4/32 GHz) Celestial Reference Frame became one of three components of the ICRF-3 in 2018. In the five years since, the X/Ka data set has increased by about 75% as well as adding the much needed north-south geometry from Japan to Australia. The latest solutions have median formal precisions of 45 μas in α cosδ and 65 μas in δ.
 The large spherical harmonic distortions seen in the ICRF3-XKa are greatly improved with the Z-dipole term reduced from 314 μas to a nearly statistically insignificant -85 +- 44 μas and with the quadrupole 2,0 magnetic term reduced to 158 +- 16 μas. We note that the X/Ka frame is derived from a limited geometry of only five observing sitesof which the two DSN baselines dominate with over 80% of the total data thus creating a susceptibility of this frame to geometric distortions. The prospects for future improvements are bright and we expect the distortions to be reduced as more data from the ESA Malargüe and JAXA Misasa stations are added.
description: Copyright © 2023, All Rights Reserved. This research was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).
description: {"references": ["Charlot, et al, Astronomical Journal, 139, 5, pp. 1713-1770, May 2010", "Charlot et al, Astronomy & Astrophysics, 644, id.A159, 28 pp., 15 Dec. 2020", "Pushkarev, A. B. ; Kovalev, Y. Y., Astronomy & Astrophysics, 544, id.A34, 52 pp., Aug. 2012", "Gaia Collaboration, Klioner, S. A, et al., Astronomy & Astrophysics, 667, November 2022"]}
Projective construction of two-dimensional symmetry-protected topological phases with U(1), SO(3), or SU(2) symmetries
Creators: name: Ye, Peng
name: Wen, Xiao-Gang
Publisher: name: arXiv
Year: 2012
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We propose a general approach to construct symmetry protected topological (SPT) states i.e the short-range entangled states with symmetry) in 2D spin/boson systems on lattice. In our approach, we fractionalize spins/bosons into different fermions, which occupy nontrivial Chern bands. After the Gutzwiller projection of the free fermion state obtained by filling the Chern bands, we can obtain SPT states on lattice. In particular, we constructed a U(1) SPT state of a spin-1 model, a SO(3) SPT state of a boson system with spin-1 bosons and spinless bosons, and a SU(2) SPT state of a spin-1/2 boson system. By applying the "spin gauge field" which directly couples to the spin density and spin current of $S^z$ components, we also calculate the quantum spin Hall conductance in each SPT state. The projective ground states can be further studied numerically in the future by variational Monte Carlo etc.
description: 7+ pages, accepted by Phys. Rev. B
Fano resonances and their control in optomechanics
Creators: name: Qu, Kenan
name: Agarwal, G. S.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The Fano line profiles, originally discovered in the context of photoionization, have been found to occur in a large class of systems like resonators, metamaterials, plasmonics. We demonstrate the existence of such resonances in cavity optomechanics by identifying the interfering contributions to the fields generated at antiStokes and Stokes frequencies. Unlike the atomic systems, the optomechanical systems provide great flexibility as the width of the resonance is controlled by the coupling field. We further show how the double cavities coupled by a single optomechanical mirror can lead to the splitting of the Fano resonance and how the second cavity can be used to tune the Fano resonances. The Fano resonances are quite sensitive to the decay parameters associated with cavities and the mechanical mirror. Such resonances can be studied by both pump probe experiments as well as via the spectrum of the quantum fluctuations in the output fields.
Non stationary multifractality in stock returns
Creators: name: Morales, Raffaello
name: Di Matteo, T.
name: Aste, Tomaso
Publisher: name: arXiv
Year: 2012
Subjects: subject: Statistical Finance (q-fin.ST)
subject: Risk Management (q-fin.RM)
subject: FOS: Economics and business

description: We perform an extensive empirical analysis of scaling properties of equity returns, suggesting that financial data show time varying multifractal properties. This is obtained by comparing empirical observations of the weighted generalised Hurst exponent (wGHE) with time series simulated via Multifractal Random Walk (MRW) by Bacry \textit{et al.} [\textit{E.Bacry, J.Delour and J.Muzy, Phys.Rev.E \,{\bf 64} 026103, 2001}]. While dynamical wGHE computed on synthetic MRW series is consistent with a scenario where multifractality is constant over time, fluctuations in the dynamical wGHE observed in empirical data are not in agreement with a MRW with constant intermittency parameter. We test these hypotheses of constant multifractality considering different specifications of MRW model with fatter tails: in all cases considered, although the thickness of the tails accounts for most of anomalous fluctuations of multifractality, still cannot fully explain the observed fluctuations.
description: 27 pages, 10 figures
Fault tolerance using whole-process migration and speculative execution
Creators: name: Smith, Justin David
Publisher: name: California Institute of Technology
Year: 2003
Subjects: functional intermediate representations
fault tolerance
migration
speculation
generational garbage collection
Computer Science
Mojave compiler

description: This thesis examines programming language concepts that facilitate fault-tolerant distributed programming. New language primitives are introduced for whole-process migration, which allows an active process to be transferred from one machine to another, and speculative execution, which enables optimistic computing based on an unverified assumption. These primitives are developed in the context of the Mojave Compiler Collection, a multi-language multi-architecture compiler with ties to the MetaPRL theorem prover.

The new primitives are first discussed from a theoretical perspective. The primitives are implemented as part of a functional intermediate language in the Mojave compiler, which has a formal operational semantics and complete typing rules. The operational semantics and typing rules are extended to accommodate whole-process migration and speculative execution, and the implications these primitives have for program safety are discussed.

The primitives are implemented as part of the Mojave compiler. The runtime safety checks that are required to ensure these primitives are safe are presented, along with runtime invariants used to justify the safety of the system. The primitives are also integrated with a novel compacting, generational garbage collector whose algorithm is presented.
Additional file 4 of Sero-epidemiology and associated factors of HIV, HBV, HCV and syphilis among blood donors in Ethiopia: a systematic review and meta-analysis
Creators: name: Melku, Mulugeta
name: Ambachew, Sintayehu
name: Enawgaw, Bamlaku
name: Abebe, Molla
name: Abebe, Zegeye
name: Deressa, Tekalign
name: Damtie, Debasu
name: Biadgo, Belete
name: Tessema, Belay
name: Geremew, Demeke
name: Kebede, Asemarie
name: Woldu, Berhanu
name: Teklu, Takele
name: Shiferaw, Elias
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Science Policy
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: 60506 Virology
subject: FOS: Biological sciences

description: Additional file 4: Figure S4. A Plot of Egger’s test of publication bias for pooled estimate of HCV among Blood donors in Ethiopia.
The stable Morse number as a lower bound for the number of Reeb chords
Creators: name: Rizell, Georgios Dimitroglou
name: Golovko, Roman
Publisher: name: arXiv
Year: 2015
Subjects: subject: Symplectic Geometry (math.SG)
subject: Geometric Topology (math.GT)
subject: FOS: Mathematics
subject: 53D12 (Primary), 53D42 (Secondary)

description: Assume that we are given a closed chord-generic Legendrian submanifold $Λ\subset P \times \mathbb R$ of the contactisation of a Liouville manifold, where $Λ$ moreover admits an exact Lagrangian filling $L_Λ \subset \mathbb R \times P \times \mathbb R$ inside the symplectisation. Under the further assumptions that this filling is spin and has vanishing Maslov class, we prove that the number of Reeb chords on $Λ$ is bounded from below by the stable Morse number of $L_Λ$. Given a general exact Lagrangian filling $L_Λ$, we show that the number of Reeb chords is bounded from below by a quantity depending on the homotopy type of $L_Λ$, following Ono-Pajitnov's implementation in Floer homology of invariants due to Sharko. This improves previously known bounds in terms of the Betti numbers of either $Λ$ or $L_Λ$.
description: 37 pages, 2 figures, final version
Superorbital entry heat transfer including atomic line radiation and massive blowing
Creators: name: Dirling, Raymond B.
Publisher: name: California Institute of Technology
Year: 1969
Subjects: Engineering and Applied Science

description: At superorbital reentry velocities radiative heating is the dominant mode of heat transfer to the stagnation region of blunt reentry vehicles. The radiative heat transfer rate at the wall is determined by the temperature profile through the shock layer which depends on the net radiative transport through both the viscous inner region adjacent to the wall and the outer region where convection and radiative transport processes dominate the energy transfer. When atomic line transitions are included a very small scale length for radiant energy transport is introduced which results in characteristic changes in the shock layer flow. The inclusion of atomic line transitions necessitates consideration of self-absorption of radiant energy and results in the coupling of radiant energy transport and convection and conduction transport processes even for relatively small vehicle nose radii.

In the formulation of this problem no restrictions are placed on the variation of the absorption coefficient of the medium with wavelength. As an illustrative example the effects of nose radius, wall reflectivity, and massive blowing have been computed for the shock layer flow field of a spherically blunted vehicle at 50,000 feet per second and 200,000 foot altitude in air.
title: Thermal Tolerance, Physiology, and Microhabitat Use of Eleutherodactylus Coqui Across an Elevational Gradient in Hawai‘i
Creators: name: Marchetti, Jack
Publisher: name: Utah State University
Year: 2023

description: The coqui frog (Eleutherodactylus coqui) is an invasive species in Hawai‘i, and has spread across much of the island. While elevational temperature differences are thought to restrict the coqui’s spread, it is unclear if they have resulted in changes to the coqui’s physiology and microhabitat use as it has expanded into higher elevations.
We first sought to determine if the coqui’s substrate use and baseline physiology differs between elevations. We found that frogs at high elevation were found closer to the forest floor and used different substrates than frogs from low and mid-elevations. This change in microhabitat use is likely in response to air temperature which tends to be warmer close to the ground at high elevation. We also found that two energy stores increased with elevation, likely to help coqui frogs cope with energetic demands of colder, less ideal temperatures. Taken together, our first study suggests the coqui’s microhabitat use and physiology does change in response to elevation.
Our second study concerned the thermal tolerance of the coqui frog in relation to elevation. We collected frogs from different elevations and tested their cold tolerance, glucose levels, and stress after three days in captivity to test for baseline elevational differences. We collected a second group of frogs and kept them in a cold- or warm-treatment for three weeks, after which we tested the same traits as above to assess the coqui’s acclimation ability according to elevation. Frogs from high elevations in the three-day group had greater cold tolerance than low elevation frogs. Cold-treated frogs in the three-week group had greater cold tolerance than warm-treated frogs. Glucose increased with elevation and was higher in cold-treated frogs after the three-week period, suggesting glucose is important for coping with cold temperatures. Finally, females had higher glucose and cellular damage than males in the three-day group. Our results indicate that coqui are more cold tolerant at high elevations, and can readily acclimate their thermal tolerance to cold temperatures, suggesting expansion into higher elevation habitats is possible.
Floer theory for Lagrangian cobordisms
Creators: name: Chantraine, Baptiste
name: Rizell, Georgios Dimitroglou
name: Ghiggini, Paolo
name: Golovko, Roman
Publisher: name: arXiv
Year: 2015
Subjects: subject: Symplectic Geometry (math.SG)
subject: FOS: Mathematics
subject: 57R58, 53D42, 53D12

description: In this article we define intersection Floer homology for exact Lagrangian cobordisms between Legendrian submanifolds in the contactisation of a Liouville manifold, provided that the Chekanov-Eliashberg algebras of the negative ends of the cobordisms admit augmentations. From this theory we derive several exact sequences relating the Morse homology of an exact Lagrangian cobordism with the bilinearised contact homologies of its ends. These are then used to investigate the topological properties of exact Lagrangian cobordisms.
description: 61 pages, 17 figures. Final version, accepted for publication in Journal of Differential Geometry, some missing citations have been added
Isobe-Kakinuma model for water waves as a higher order shallow water approximation
Creators: name: Iguchi, Tatsuo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We justify rigorously an Isobe-Kakinuma model for water waves as a higher order shallow water approximation in the case of a flat bottom. It is known that the full water wave equations are approximated by the shallow water equations with an error of order $O(δ^2)$, where $δ$ is a small nondimensional parameter defined as the ratio of the mean depth to the typical wavelength. The Green-Naghdi equations are known as higher order approximate equations to the water wave equations with an error of order $O(δ^4)$. In this paper we show that the Isobe-Kakinuma model is a much higher order approximation to the water wave equations with an error of order $O(δ^6)$.
description: 25 pages
Additional file 5 of Sero-epidemiology and associated factors of HIV, HBV, HCV and syphilis among blood donors in Ethiopia: a systematic review and meta-analysis
Creators: name: Melku, Mulugeta
name: Ambachew, Sintayehu
name: Enawgaw, Bamlaku
name: Abebe, Molla
name: Abebe, Zegeye
name: Deressa, Tekalign
name: Damtie, Debasu
name: Biadgo, Belete
name: Tessema, Belay
name: Geremew, Demeke
name: Kebede, Asemarie
name: Woldu, Berhanu
name: Teklu, Takele
name: Shiferaw, Elias
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Science Policy
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: 60506 Virology
subject: FOS: Biological sciences

description: Additional file 5: Figure S5. A Plot of Egger’s test of publication bias for pooled estimate of Syphilis among Blood donors in Ethiopia.
Trailing edge noise theory for rotating blades in uniform flow
Creators: name: Sinayoko, Samuel
name: Kingan, Mike
name: Agarwal, Anurag
Publisher: name: arXiv
Year: 2013
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: This paper presents a new formulation for trailing edge noise radiation from rotating blades based on an analytical solution of the convective wave equation. It accounts for distributed loading and the effect of mean flow and spanwise wavenumber. A commonly used theory due to Schlinker and Amiet (1981) predicts trailing edge noise radiation from rotating blades. However, different versions of the theory exist; it is not known which version is the correct one and what the range of validity of the theory is. This paper addresses both questions by deriving Schlinker and Amiet's theory in a simple way and by comparing it to the new formulation, using model blade elements representative of a wind turbine, a cooling fan and an aircraft propeller. The correct form of Schlinker and Amiet's theory (1981) is identified. It is valid at high enough frequency, i.e. for a Helmholtz number relative to chord greater than one and a rotational frequency much smaller than the angular frequency of the noise sources.
description: 28 pages, 10 figures, submitted to Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences (final revision)
Normal modes in damped systems
Creators: name: O'Kelly, Michael Edmond James
Publisher: name: California Institute of Technology
Year: 1961
Subjects: subject: Housner Earthquake Engineering Collection
subject: Mechanical Engineering
subject: FOS: Mechanical engineering
subject: Engineer's thesis

description: A general review of normal mode theory as applied to the vibration of linear damped lumped parameter bilateral systems is presented. It is shown that systems possessing classical damping may always be solved by the method developed by Rayleigh. However, for more general type non-classical damping the method proposed by F. A. Foss must be used. The main differences between classical and non-classical normal modes are noted. A non-classically damped system which does not possess a mode type solution is solved by La place Transform techniques. The effect of damping on the natural frequencies of a linear system is discussed. It is shown that in classically damped systems increasing the damping decreases the natural frequencies of the system. With non-classical damping some of the natural frequencies of the damped system may be greater than the corresponding natural frequencies of the undamped system. From the perturbation analysis, used in determining the effect of damping on the natural frequencies of the system, the concept of equivalent classical damping for non-classically damped systems is derived. Experimental techniques needed to determine the mode shapes, natural frequencies, mass spring and damping matrices of classically damped systems are presented. By the use of the concept of equivalent classical damping an estimate of the damping matrix in non-classical systems may be obtained. Experimental results supporting the theory are presented.
Solvability of the initial value problem to the Isobe-Kakinuma model for water waves
Creators: name: Nemoto, Ryo
name: Iguchi, Tatsuo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We consider the initial value problem to the Isobe-Kakinuma model for water waves and the structure of the model. The Isobe-Kakinuma model is the Euler-Lagrange equations for an approximate Lagrangian which is derived from Luke's Lagrangian for water waves by approximating the velocity potential in the Lagrangian. The Isobe-Kakinuma model is a system of second order partial differential equations and is classified into a system of nonlinear dispersive equations. Since the hypersurface $t=0$ is characteristic for the Isobe-Kakinuma model, the initial data have to be restricted in an infinite dimensional manifold for the existence of the solution. Under this necessary condition and a sign condition, which corresponds to a generalized Rayleigh-Taylor sign condition for water waves, on the initial data, we show that the initial value problem is solvable locally in time in Sobolev spaces. We also discuss the linear dispersion relation to the model.
Additional file 6 of Sero-epidemiology and associated factors of HIV, HBV, HCV and syphilis among blood donors in Ethiopia: a systematic review and meta-analysis
Creators: name: Melku, Mulugeta
name: Ambachew, Sintayehu
name: Enawgaw, Bamlaku
name: Abebe, Molla
name: Abebe, Zegeye
name: Deressa, Tekalign
name: Damtie, Debasu
name: Biadgo, Belete
name: Tessema, Belay
name: Geremew, Demeke
name: Kebede, Asemarie
name: Woldu, Berhanu
name: Teklu, Takele
name: Shiferaw, Elias
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Science Policy
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: 60506 Virology
subject: FOS: Biological sciences

description: Additional file 6: Figure S6. Effect size of sex on HCV infection among blood donors in Ethiopia—a sub-group analysis by geographic region.
The COS/UVES Absorption Survey of the Magellanic Stream: II. Evidence for a complex enrichment history of the Stream from the Fairall 9 sightline
Creators: name: Richter, Philipp
name: Fox, Andrew J.
name: Wakker, Bart P.
name: Lehner, Nicolas
name: Howk, J. Christopher
name: Bland-Hawthorn, Joss
name: Bekhti, Nadya Ben
name: Fechner, Cora
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present a multi-wavelength study of the Magellanic Stream (MS), a massive gaseous structure in the Local Group that is believed to represent material stripped from the Magellanic Clouds. We use ultraviolet, optical and radio data obtained with HST/COS, VLT/UVES, FUSE, GASS, and ATCA to study metal abundances and physical conditions in the Stream toward the quasar Fairall 9. Line absorption in the MS from a large number of metal ions and from molecular hydrogen is detected in up to seven absorption components, indicating the presence of multi-phase gas. From the analysis of unsaturated SII absorption, in combination with a detailed photoionization model, we obtain a surprisingly high alpha abundance in the Stream toward Fairall 9 of [S/H]=-0.30pm0.04 (0.5 solar). This value is 5 times higher than what is found along other MS sightlines based on similar COS/UVES data sets. In contrast, the measured nitrogen abundance is found to be substantially lower ([N/H]=-1.15pm0.06), implying a very low [N/alpha] ratio of -0.85 dex. The substantial differences in the chemical composition of MS toward Fairall 9 compared to other sightlines point toward a complex enrichment history of the Stream. We favour a scenario, in which the gas toward Fairall 9 was locally enriched with alpha elements by massive stars and then was separated from the Magellanic Clouds before the delayed nitrogen enrichment from intermediate-mass stars could set in. Our results support (but do not require) the idea that there is a metal-enriched filament in the Stream toward Fairall 9 that originates in the LMC.
description: Accepted for publication in ApJ; 20 pages, 11 figures
Die Aachener Goldschmiedefamilie von Rath (1604-1673)
Creators: name: Schmitz-Cliever, Herta
Publisher: name: Aachener Kunstblätter
Year: 2017

description: -
description: Aachener Kunstblätter, Bd. 47 (1976-1977): Aachener Kunstblätter
title: Convexity Applications in Single and Multi-Agent Control
Creators: name: Jansson, Olli Nikodeemus
Publisher: name: Utah State University
Year: 2023

description: The focus of this dissertation is in the application of convexity for control problems; specifically, single-agent problems with linear or nonlinear dynamics and multi-agent problems with linear dynamics. A mixture of convex and non-convex constraints for optimal control problems is also considered. The main contributions of this dissertation include: 1) a convexification of single-agent problems with linear dynamics and annular control constraint, 2) a technique for controlling bounded nonlinear single-agent systems, and 3) a technique for solving multi-agent pursuit-evasion games with linear dynamics and convex control and state constraints. The first result shows that for annularly constrained linear systems, controllability is a sufficient condition for a free or fixed time problem to be solvable as a sequence of convex optimization problems. The second result shows that if a nonlinear system is bounded and “ordered”, it is possible to use a convex combination of bounding linear systems to design a control for the nonlinear system. The third result takes advantage of a convex reachable set computation for each agent in solving games using a geometrical approach. Altogether, the theoretical and computational results demonstrate the significance of convex analysis in solving non-convex control problems.
An algebraic formulation of causality for noncommutative geometry
Creators: name: Franco, Nicolas
name: Eckstein, Michał
Publisher: name: arXiv
Year: 2012
Subjects: subject: Mathematical Physics (math-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Operator Algebras (math.OA)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 58B34, 53C50, 46C20, 15A66

description: We propose an algebraic formulation of the notion of causality for spectral triples corresponding to globally hyperbolic manifolds with a well defined noncommutative generalization. The causality is given by a specific cone of Hermitian elements respecting an algebraic condition based on the Dirac operator and a fundamental symmetry. We prove that in the commutative case the usual notion of causality is recovered. We show that, when the dimension of the manifold is even, the result can be extended in order to have an algebraic constraint suitable for a Lorentzian distance formula.
description: 24 pages, minor changes from v2, to appear in Classical and Quantum Gravity
Implementing Data Services for Indigenous Scholarship and Sovereignty
Creators: name: Belarde-Lewis, Miranda
name: Karcher, Sebastian
name: Littletree, Sandy
name: Palmer, Carole
name: Weber, Nic
Publisher: name: Zenodo
Year: 2023
Subjects: Indigenous data
Indigenous data sovereignty
qualitative data
CARE Principles

description: In response to the imperative for Indigenous data governance and sovereignty, a groundswell of activity has emerged on the ethical care and stewardship of digital Indigenous data. To date, however, there is little guidance for libraries and repositories on how to implement Indigenous data principles (such as the CARE principles or ‘data sovereignty’) within their existing research data services (RDS). Based on case studies of Indigenous scholarship by Indigenous researchers, and a strategic collaboration among a data repository, library professionals, and information researchers this paper will present initial results from a project seeking to establish guidelines for RDS with a focus on Indigenous data from the humanities and qualitative social sciences. The collaborative approach integrates data curation and infrastructure expertise from the Qualitative Data Repository (QDR) and the Information School at the University of Washington with librarianship expertise from the X̱wi7x̱wa Library at the University of British Columbia and Data Services at UW Libraries.

 We focus on three key areas: 1) Collection development: how should repositories decide on whether to accept deposits of Indigenous data? Repositories must ensure that data were collected ethically and that depositors have the authority to make them available to others. 2) Metadata: what are some key considerations for ensuring that appropriate context and representation of relational accountability are included with Indigenous data? Against the backdrop of a history of racist and colonialist description of Indigenous culture in libraries and archives, it is particularly important that metadata accurately reflects Indigenous perspectives of data. 3) Governance and access: how can appropriate access to, and control of, data be managed? While many Indigenous people and scholars want to see data preserved and made available, it is important to ensure that governance mechanisms respect Indigenous sovereignty as well as contain access controls that meet the needs of Indigenous communities.
description: Supported by funding from the Mellon Foundation: https://mellon.org/grants/grants-database/grants/university-of-washington/2104-10533/
Experimental investigation of detached shock waves on a 70 degree cone at various angles of attack
Creators: name: Frick, Leo F.
Publisher: name: California Institute of Technology
Year: 1950
Subjects: Aeronautics

description: An experimental investigation was made to determine the variation of shock shape and extent of subsonic region behind the shock wave with angle of attack for a 70° cone at various Mach numbers. The main interest was centered on those Mach numbers which produced detached shock waves or for which the possibility of detachment at angle of attack existed.

The tests were conducted in the GALCIT 2.5" Supersonic Wind Tunnel at angles of attack of 0°, 3°, 6°, 9°, 12°, and 15° and Mach numbers of 1.438, 1.544, 1.584, 1.857, 1.986, and 3.01.

It was found that, with increasing angle of attack and constant Mach number, the subsonic region behind the shock wave increased in the lower portion and decreased in the upper portion. With increasing Mach number the subsonic region decreased for all angles of attack. Interaction between the upper and lower portions of the shock wave affects the subsonic region behind the wave, suppressing its appearance on the upper surface, retarding its disappearance from the lower surface.
Carbon formation from acetylene in the shock tube
Creators: name: Bennett, Eugene Newell
Publisher: name: California Institute of Technology
Year: 1956
Subjects: Aeronautics

description: The use of the shock tube for the study of carbon formation from acetylene has been considered theoretically and studied experimentally.

In the calculations, the state of the gas is determined behind incident and reflected shocks for a wide range of shock strengths and for various excitation models of the internal degrees of freedom. A simple mechanism has been assumed for the thermal decomposition, namely the formation of solid carbon and hydrogen. Estimates are presented for the minimum times spent by the gas in a uniform state at the elevated temperatures behind reflected shocks.

The shock strengths required to initiate decomposition of acetylene at various pressures have been investigated experimentally. Temperature estimates and shock velocity measurements suggest that the effective specific heat ratio approaches the equilibrium value. Spectroscopic studies have been carried out to determine the light emitted in a narrow wave length region during chemical decomposition behind reflected shocks. The results show that the intensity distribution follows the black-body emission law. Therefore, a two-color method may be used in future studies for determining the temperature as a function of time behind carbon forming shocks.
Relativistic corrections to η_c-pair production in high energy proton-proton collisions
Creators: name: Martynenko, A. P.
name: Trunin, A. M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: On the basis of perturbative QCD and the relativistic quark model we calculate relativistic corrections to the double $η_c$ meson production in proton-proton interactions at LHC energies. Relativistic terms in the production amplitude connected with the relative motion of heavy quarks and the transformation law of the bound state wave functions to the reference frame of moving charmonia are taken into account. For the gluon and quark propagators entering the amplitude we use a truncated expansion in relative quark momenta up to the second order. Relativistic corrections to the quark bound state wave functions are considered by means of the Breit-like potential. It turns out that the examined effects decrease total nonrelativistic cross section more than two times and on 20 percents in the rapidity region of LHCb detector.
description: 12 pages, 3 figures
Spatiotemporal Characterization of VIIRS Night Light
Creators: name: Small, Christopher
Publisher: name: Columbia University
Year: 2021
Subjects: Remote sensing
Remote-sensing images
Photographic interpretation

description: The Visible Infrared Imaging Radiometer Suite (VIIRS) Day Night Band (DNB) on board the Suomi NPP satellite now provides almost a decade of daily observations of night light. The temporal frequency of sampling, without the degree of temporal averaging of annual composites, makes it necessary to consider the distinction between apparent temporal changes of night light related to the imaging process and actual changes in the underlying sources of the night light being imaged. The most common approach to night light change detection involves direct attribution of observed changes to the phenomenon of interest. Implicit in this approach is the assumption that other forms of actual and apparent change in the light source are negligible or non-existent. An alternative approach is to characterize the spatiotemporal variability prior to deductive attribution of causation so that the attribution can be made in the context of the full range of spatial and temporal variation. The primary objective of this study is to characterize night light variability over a range of spatial and temporal scales to provide a context for interpretation of night light changes observed on both subannual and interannual time scales. This analysis is based on a combination of temporal moments, spatial correlation and Empirical Orthogonal Function (EOF) analysis. A key result of this study is the pervasive heteroskedasticity of VIIRS monthly mean night light. Specifically, the monotonic decrease of variability with increasing mean brightness. Anthropogenic night light is remarkably stable on subannual time scales while background luminance varies considerably. The variance partition from the eigenvalues of the spatiotemporal covariance matrix are 88, 2 and 2% for spatial, seasonal and interannual variance (respectively) in the most diverse region on Earth (Eurasia). Heteroskedasticity is pervasive in the monthly composites; present in all areas for all months of the year, suggesting that much, if not most, of the month-to- month variability may be related to luminance of otherwise stable sources subjected to multiple aspects of the imaging process varying in time. Given the skewed distribution of all night light arising from radial peripheral dimming of bright sources subject to atmospheric scattering, even aggregate metrics using thresholds must be interpreted in light of the fact that much larger numbers of more variable low luminance pixels may statistically overwhelm smaller numbers of stable higher luminance pixels and cause apparent changes related to the imaging process to be interpreted as actual changes in the light sources.
A FAMÍLIA E O AFETO: O Dever Fundamental dos Pais em dar Afeto aos Filhos como Mecanismo de Proteção ao Desenvolvimento da Personalidade e Concretização da Dignidade Humana
Creators: name: Florindo da Silva, Heleno
name: Cesar Fabriz, Daury
Publisher: name: Zenodo
Year: 2023

description: O presente trabalho apresentará discussões, a partir de uma abordagem dialética, acerca da existência, ou não, de um dever fundamental dos pais em dar afeto aos filhos como mecanismo de proteção ao desenvolvimento de sua personalidade e concretização de sua dignidade humana, apontando, para tanto, a constitucionalização do afeto nas relações de família e, a partir disso, as discussões acerca da aplicação horizontal dos direitos fundamentais, bem como a demonstração da importância do afeto, à luz da psicanálise, para a formação da personalidade dos indivíduos e, ao fim, a constatação da necessária análise psicanalítica das relações afetivas do Direito de Família, concluindo pela existência de um dever fundamental dos pais, a partir do princípio da proteção integral da criança, em dar afeto aos seus filhos.