cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Red Giant Branch in the Tycho-2 Catalogue
Creators: name: Gontcharov, George
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Based on multicolor photometry from the 2MASS and Tycho-2 catalogues, we have produced a sample of 38 368 branch red giants that has less than 1\% of admixtures and is complete within 500 pc of the Sun. The sample includes 30 671 K giants, 7544 M giants, 49 C giants, and 104 suspected supergiants or S stars. The photometric distances have been calculated for K, M, and C stars with an accuracy of 40\%. Tycho-2 proper motions and PCRV radial velocities are used to analyze the stellar kinematics. The decrease in the stellar distribution density with distance from the Galactic equator approximated by the barometric law, contrary to the Besancon model of the Galaxy, and the kinematic parameters calculated using the Ogorodnikov--Milne model characterize the overwhelming majority of the selected K and M giants as disk stars with ages of more than 3 Gyr. A small number of K and M giants are extremely young or, conversely, thick-disk ones. The latter show a nonuniform distribution in the phase space of coordinates and velocities, arguing against isothermality and full relaxation of the disk and for the theory of dynamical streams or superclusters. The spatial distribution and kinematics of the selected C stars force us to consider them as asymptotic branch giants with masses of more than 2 $M_{\odot}$ and ages of less than 2 Gyr probably associated with the Gould Belt. The offset of the Sun above the Galactic equator has been found from the distribution of stars to be $13\pm2$ pc, which coincides with the previously obtained value for the clump red giants.
description: 5 figures, 1 table
An analysis of nonadiabatic ring-polymer molecular dynamics and its application to vibronic spectra
Creators: name: Richardson, Jeremy O.
name: Meyer, Philipp
name: Pleinert, Marc-Oliver
name: Thoss, Michael
Publisher: name: arXiv
Year: 2016
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Nonadiabatic ring-polymer molecular dynamics employs the mapping approach to describe nonadiabatic effects within the ring-polymer ansatz. In this paper, it is generalized to allow for the nuclear and electronic degrees of freedom to be described by different numbers of ring-polymer beads. Analysis of the resulting method shows that as the number of electronic mapping variables increases, certain problems associated with the approach are removed, such as the non-unique choice of the mapping Hamiltonian and negative populations leading to inverted potential-energy surfaces. Explicit integration over cyclic variables reduces the sign problem for the initial distribution in the general case. A new application for the simulation of vibronic spectra is described and promising results are presented for a model system.
description: 28 pages, 4 figures; submitted to Chem. Phys
Essays on Stochastic Frontier Models
Creators: name: Jonuzaj, Mariol
Publisher: name: Lancaster University
Year: 2023

description: This thesis consists of three independent chapters. The first chapter “Bayesian Inference in Dynamic Panel Stochastic Frontier Models” proposes a new stochastic frontier model which accounts for the intertemporal production behaviour. The conceptualization is based on the notion that firms face production adjustment costs in the short run due to the presence of quasi-fixed inputs. Consequently, this sluggish adjustment of the entire production process will create a dependency between the current and past production state. To capture this dynamic process, this chapter utilizes the traditional partial adjustment mechanism. The mechanism delivers a dynamic specification and allows factor inputs and inefficiency shocks to have an intertemporal effect on the production process. Moreover, the model allows heterogeneous adjustment speeds and input elasticities across the production units. Model inference is based on Bayesian MCMC techniques with data-augmentation. We illustrate the new model in an empirical application where we estimate the productivity and efficiency growth of the Egyptian private manufacturing sector during the early 90’s. In a similar vein, the second chapter, “Dynamic Panel Stochastic Frontier Models with Inefficiency Effects”, deals with dynamic panel frontier models where inefficiency effects can be a function of exogenous environmental variables. This chapter builds upon advancements in the field and utilizes parametric cumulative distribution functions to specify technical efficiency. The proposed model allows the presence of fixed effects and time-varying inefficiencies. Model estimation is based on the Generalized Method of Moments (GMM) approach, where various forms of input endogeneity can be effectively addressed. Last, the third chapter “A simple method for modelling the energy efficiency rebound effects with an application to energy demand frontiers” proposes a new simple method for estimating the energy inefficiency rebound effects. Model estimation is based on a two-stage approach. In the first stage, we argue in estimating a reduced form stochastic frontier model with country-specific inefficiency heteroscedastic effects. In the second stage, the energy efficiency rebound effects can be obtained effectively using moment-matching methods such as the GMM approach. We apply the proposed model on aggregate energy frontiers where we estimate the energy efficiency and the corresponding rebound effects for a balanced panel of OECD economies. The empirical results suggest an overall upward trend of energy efficiency scores. The energy rebound effects range from 28% to 92%, indicating that energy efficiency actions could have a limited impact on achieving environmental objectives.
Unveiling multiple AGN activity in galaxy mergers
Creators: name: De Rosa, A.
name: Bianchi, S.
name: Bogdanovic, T.
name: Decarli, R.
name: Heidt, J.
name: Herrero-Illana, R.
name: Husemann, B.
name: Komossa, S.
name: Kun, E.
name: Loiseau, N.
name: Guainazzi, M.
name: Paragi, Z.
name: Perez-Torres, M.
name: Piconcelli, E.
name: Schawinski, K.
name: Vignali, C.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: In this paper we present an overview of the MAGNA (Multiple AGN Activity) project aiming at a comprehensive study of multiple supemassive black hole systems. With the main goal to characterize the sources in merging systems at different stages of evolution, we selected a sample of objects optically classified as multiple systems on the basis of emission line diagnostics and started a massive multiband observational campaign. Here we report on the discovery of the exceptionally high AGN density compact group SDSS~J0959+1259. A multiband study suggests that strong interactions are taking place among its galaxies through tidal forces, therefore this system represents a case study for physical mechanisms that trigger nuclear activity and star formation. We also present a preliminary analysis of the multiple AGN system SDSS~J1038+3921.}
description: Proceedings paper for "XMM-Newton: The Next Decade" (held in 2016 May); accepted to be published in Astronomische Nachrichten / Astronomical Notes (AN)
Electroabsorption in MoS$_2$
Creators: name: Vella, Daniele
name: Ovchinnikov, Dmitry
name: Martino, Nicola
name: Vega-Mayoral, Victor
name: Dumcenco, Dumitru
name: Kung, Yen-Chen
name: Antognazza, Maria-Rosa
name: Kis, Andras
name: Lanzani, Guglielmo
name: Mihailovic, Dragan
name: Gadermaier, Christoph
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: To translate electrical into optical signals one uses the modulation of either the refractive index or the absorbance of a material by an electric field. Contemporary electroabsorption modulators (EAMs) employ the quantum confined Stark effect (QCSE), the field-induced red-shift and broadening of the strong excitonic absorption resonances characteristic of low-dimensional semiconductor structures. Here we show an unprecedentedly strong transverse electroabsorption (EA) signal in a monolayer of the two-dimensional semiconductor MoS2. The EA spectrum is dominated by an apparent linewidth broadening of around 15% at a modulated voltage of only Vpp = 0.5 V. Contrary to the conventional QCSE, the signal increases linearly with the applied field strength and arises from a linear variation of the distance between the strongly overlapping exciton and trion resonances. The achievable modulation depths exceeding 0.1 dBnm-1 bear the scope for extremely compact, ultrafast, energy-efficient EAMs for integrated photonics, including on-chip optical communication.
title: Ein Lorbeerzweig für Friedrich den Großen
title: Wilhelmine von Bayreuth am Grab Vergils (1755)
titleType: Subtitle
Creators: name: Baum, Constanze
Publisher: name: Humboldt-Universität zu Berlin
Year: 2006
Subjects: subject: Kavaliersreise
subject: Friedrich der Große
subject: Wilhelmine von Bayreuth
subject: Vergil
subject: Lorbeerkranz
subject: Orakel
subject: Briefe
subject: Grabmal
subject: 830 Deutsche Literatur und Literaturen verwandter Sprachen

description: Friedrich dem Großen (1712-1786) bleibt eine Kavaliersreise durch Italien Zeit seines Lebens verwehrt. Seine um drei Jahre ältere Schwester, Wilhelmine von Bayreuth (1709-1758), jedoch besucht die antiken Stätten und sendet ihrem Bruder einen Lorbeerkranz vom Grab Vergils bei Neapel. Zu diesem Andenken fügt sie einen Brief, in dem sie für ihren Bruder ein literarisch-allegorisches Bild schafft, und ein Gedicht ihres Reisebegleiters Charles Marie de La Condamine (1701-1774) beilegt, welches ihre Beschreibung poetisch überhöht. In ihrem Brief inszeniert Wilhelmine das Grab zum Orakel, aus dem die Stimme des Dichters dringt, ihren Bruder zum Apoll und sich selbst zur Muse erhebt. Stilistisch und inhaltlich hebt sich ihr Brief damit von anderen Briefen an ihren Bruder ab, welche sonst auf das Sehen und Beschreiben beschränkt sind, um dem Zurückgebliebenen das Buchwissen mit ihren Eindrücken zu ersetzen. Als Idee eines genius loci findet das Grabmal Eingang in die Gärten von Bayreuth, Sanssouci und Rheinsberg, wo es unter anderem die eigentliche Persönlichkeit des Königs repräsentiert – den Philosoph und Dichter.
Symmetry and Natural Quantum Structures for Three-Particles in One-Dimension
Creators: name: Harshman, N. L.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: How do symmetries induce natural and useful quantum structures? This question is investigated in the context of models of three interacting particles in one-dimension. Such models display a wide spectrum of possibilities for dynamical systems, from integrability to hard chaos. This article demonstrates that the related but distinct notions of integrability, separability, and solvability identify meaningful collective observables for Hamiltonians with sufficient symmetry. In turn, these observables induce tensor product structures on the Hilbert space that are especially useful for storing and processing quantum information and provide guidance to interpretation and phenomenology of quantum few-body physics.
description: This is an essay to be published as a book chapter in "Quantum Structural Studies: Classical Emergence from the Quantum Level", R.E. Kastner, J. Jeknic-Dugic, G. Jaroszkiewicz (Eds.), World Scientific. 24 pages preprint format
Nuclear matter properties from local chiral interactions with $Δ$ isobar intermediate states
Creators: name: Logoteta, Domenico
name: Bombaci, Ignazio
name: Kievsky, Alejandro
Publisher: name: arXiv
Year: 2016
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Using two-nucleon and three-nucleon interactions derived in the framework of chiral perturbation theory (ChPT) with and without the explicit $Δ$ isobar contributions, we calculate the energy per particle of symmetric nuclear matter and pure neutron matter in the framework of the microscopic Brueckner-Hartree-Fock approach. In particular, we present for the first time nuclear matter calculations using the new fully local in coordinate-space two-nucleon interaction at the next-to-next-to-next-to-leading-order (N3LO) of ChPT with $Δ$ isobar intermediate states (N3LO$Δ$) recently developed by Piarulli et al. [arXiv:1606:06335]. We find that using this N3LO$Δ$ potential, supplemented with a local N2LO three-nucleon interaction with explicit $Δ$ isobar degrees of freedom, it is possible to obtain a satisfactory saturation point of symmetric nuclear matter. For this combination of two- and three-nucleon interactions we also calculate the nuclear symmetry energy and we compare our results with the empirical constraints on this quantity obtained using the excitation energies to isobaric analog states in nuclei and using experimental data on the neutron skin thickness of heavy nuclei, finding a very good agreement with these empirical constraints in all the considered nucleonic density range. In addition, we find that the explicit inclusion of $Δ$ isobars diminishes the strength of the three-nucleon interactions needed the get a good saturation point of symmetric nuclear matter. We also compare the results of our calculations with those obtained by other research groups using chiral nuclear interactions with different many-body methods, finding in many cases a very satisfactory agreement.
Emergent Electric Polarization by Kondo Effect in a Triangular Triple Quantum Dot
Creators: name: Koga, Mikito
name: Matsumoto, Masashige
name: Kusunose, Hiroaki
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: A triangular triple quantum dot gives various Kondo effects, such as the emergence of an electric polarization accompanied by a complete compensation of spin degrees of freedom. The interplay of spin and charge of electrons in quantum dots is investigated using an Anderson model with an equilateral triangular spin cluster, in which a single electron state at one site is hybridized with a conduction band in a lead. The numerical renormalization group analysis shows how a nonzero electric polarization develops with local electrons traveling in the loop and how it depends on the hybridization strength as an experimentally controllable parameter in the Kondo effect.
description: 5 pages, 5 figures
Selfish Pups: Weaning Conflict and Milk Theft in Free-Ranging Dogs
Creators: name: Paul, Manabi
name: Bhadra, Anindita
Publisher: name: arXiv
Year: 2016
Subjects: subject: Other Quantitative Biology (q-bio.OT)
subject: FOS: Biological sciences

description: Parent-offspring conflict theory predicts the emergence of weaning conflict between a mother and her offspring arising from skewed relatedness benefits. Empirical observations of weaning conflict has not been carried out in canids. In a field-based study on free-ranging dogs we observed that suckling bout durations reduce, proportion of mother-initiated suckling bouts reduce and mother-initiated suckling terminations increase, with pup age. We identified the 7th - 13th week period of pup age as the zone of conflict between the mother and her pups, beyond which suckling solicitations cease, and before which suckling refusals are few. We also report for the first time milk theft by pups who take advantage of the presence of multiple lactating females, due to the promiscuous mating system of the dogs. This behaviour, though apparently disadvantageous for the mothers, is perhaps adaptive for the dogs in the face of high mortality and competition for resources.
description: 3 figures, 1 table
Complexes of triggered star formation in supergiant shell of Holmberg II
Creators: name: Egorov, Oleg V.
name: Lozinskaya, Tatiana A.
name: Moiseev, Alexei V.
name: Shchekinov, Yuri A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We report a detailed analysis of all regions of current star formation in the walls of the supergiant HI shell (SGS) in the galaxy Holmberg II based on observations with a scanning Fabry-Perot interferometer at the 6-m SAO RAS telescope. We compare the structure and kinematics of ionized gas with that of atomic hydrogen and with the stellar population of the SGS. Our deep H$α$ images and archival images taken by the HST demonstrate that current star formation episodes are larger and more complicated than previously thought: they represent unified star-forming complexes with sizes of several hundred pc rather than 'chains' of separate bright nebulae in the walls of the SGS. The fact that we are dealing with unified complexes is evidenced by identified faint shell-like structures of ionized and neutral gas which connect several distinct bright HII regions. Formation of such complexes is due to the feedback of stars with very inhomogeneous ambient gas in the walls of the SGS. The arguments supporting an idea about the triggering of star formation in SGS by the HI supershells collision are presented. We also found a faint ionized supershell inside the HI SGS expanding with a velocity of no greater than 10-15 km/s. Five OB stars located inside the inner supershell are sufficient to account for its radiation, although a possibility of leakage of ionizing photons from bright HII regions is not ruled out as well.
description: 23 pages, 14 figures, 4 tables. Accepted for publication in MNRAS
Exoplanet Exposure Triangle: Optimising spectroscopic observations of transiting exoplanets
Creators: name: Boldt-Christmas, Linn
name: Lesjak, Fabio
name: Wehrhahn, Ansgar
name: Piskunov, Nikolai
name: Rains, Adam D.
name: Nortmann, Lisa
name: Kochukhov, Oleg
name: Heiter, Ulrike
Publisher: name: Zenodo
Year: 2023

description: Transiting exoplanets provide opportunities for us to observe their atmospheres and to analyse them using spectroscopy. As the characterisation of exoplanet atmospheres relies on the detection of spectrally resolved features, analysis can be improved with high signal-to-noise ratios (SNR) that are possible to obtain today with modern spectrographs. However, obtaining high SNR through adjusting exposure times comes with a trade-off. A higher cadence of several, shorter exposures minimises the spectral feature smearing that arises due to the continuously changing radial velocity of the planet; but a lower cadence of fewer, longer exposures collects more photons with reduced overheads and readout noise, enhancing the SNR of each observation. As such, there is a need to establish what the optimal compromise is between the SNR and time resolution for a given target. In this poster, I present a new method that will aid observational astronomers in establishing the optimal parameters for observing transiting exoplanets with spectroscopic instruments. The method is demonstrated using simulated spectra, cross-correlation, and other statistical techniques. This will be particularly relevant for planning ground-based observational studies to characterise atmospheres for objects around cooler stars with more complex stellar spectra.
description: {"references": ["Lam K. W., et al., 2017, A&A, 599, 1", "Seidel, J. V., et al. 2020, A&A, 643, A45", "Dorn, R. J., et al. 2023, A&A, 671, A24", "Tamuz, O., et al. 2005, MNRAS, 356, 1466\u20131470"]}
Spiral structures and temperature distribution in the quiescent accretion disc of the cataclysmic binary V2051 Ophiuchi
Creators: name: Rutkowski, Artur
name: Waniak, Waclaw
name: Preston, George W.
name: Pych, Wojciech
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present the capabilities of our new code for obtaining Doppler maps implementing the maximum likelihood approach. As test data, we used observations of the dwarf nova V2051 Ophiuchi. The system was observed in quiescence at least 16 d before the onset of the next outburst. Using Doppler maps obtained for ten emission lines covering three orbital cycles, we detected spiral structures in the accretion disc of V2051 Oph. However, these structures could be biased as our data sampled the orbital period of the binary at only eight different orbital phases. Our Doppler maps show evolution from a one-arm wave structure in H$α$ to two-armed waves in the other lines. The location of the two-arm structures agrees with simulations showing tidally driven spiral waves in the accretion disc. During consecutive cycles, the qualitative characteristics of the detected structures remained similar but the central absorption increased. For the first time, using the Doppler tomography method, we obtained temperature maps of the accretion disc. However, taking into account all the assumptions involved when using our method to retrieve them, the result should be treated with caution. Our maps present a relatively flat distribution of the temperature over the disc, showing no temperature increase at the location of the spiral arms. Using `ring masking', we have revealed an ionized region located close to the expected location of stream--disc interactions. We found the average temperature of the accretion disc to be 5600 K, which is below the critical limit deduced from the disc instability model.
description: Accepted for publication in MNRAS
The Morrison-Kawamata Cone Conjecture and Abundance on Ricci flat manifolds
Creators: name: Lazić, Vladimir
name: Oguiso, Keiji
name: Peternell, Thomas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14E30, 14F10, 14J30, 14J32, 32Q25, 14E07, 14J50

description: The aim of this survey paper is threefold: (a) to discuss the status of the Morrison-Kawamata cone conjecture, (b) to report on recent developments towards the Abundance Conjecture, and (c) to discuss the nef line bundle version of the Abundance Conjecture on $K$-trivial varieties.
description: the final version, to appear in the proceedings of the conference Uniformization, Riemann-Hilbert Correspondence, Calabi-Yau manifolds, and Picard-Fuchs Equations, held at the Institut Mittag-Leffler, July 2015
Safety Barrier Certificates for Heterogeneous Multi-Robot Systems
Creators: name: Wang, Li
name: Ames, Aaron
name: Egerstedt, Magnus
Publisher: name: arXiv
Year: 2016
Subjects: subject: Robotics (cs.RO)
subject: Optimization and Control (math.OC)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: This paper presents a formal framework for collision avoidance in multi-robot systems, wherein an existing controller is modified in a minimally invasive fashion to ensure safety. We build this framework through the use of control barrier functions (CBFs) which guarantee forward invariance of a safe set; these yield safety barrier certificates in the context of heterogeneous robot dynamics subject to acceleration bounds. Moreover, safety barrier certificates are extended to a distributed control framework, wherein neighboring agent dynamics are unknown, through local parameter identification. The end result is an optimization-based controller that formally guarantees collision free behavior in heterogeneous multi-agent systems by minimally modifying the desired controller via safety barrier constraints. This formal result is verified in simulation on a multi-robot system consisting of both cumbersome and agile robots, is demonstrated experimentally on a system with a Magellan Pro robot and three Khepera III robots.
description: 8 pages version of 2016ACC conference paper, experimental results added
Dynamical structure of magnetized dissipative accretion flow around black holes
Creators: name: Sarkar, Biplob
name: Das, Santabrata
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We study the global structure of optically thin, advection dominated, magnetized accretion flow around black holes. We consider the magnetic field to be turbulent in nature and dominated by the toroidal component. With this, we obtain the complete set of accretion solutions for dissipative flows where bremsstrahlung process is regarded as the dominant cooling mechanism. We show that rotating magnetized accretion flow experiences virtual barrier around black hole due to centrifugal repulsion that can trigger the discontinuous transition of the flow variables in the form of shock waves. We examine the properties of the shock waves and find that the dynamics of the post-shock corona (PSC) is controlled by the flow parameters, namely viscosity, cooling rate and strength of the magnetic field, respectively. We separate the effective region of the parameter space for standing shock and observe that shock can form for wide range of flow parameters. We obtain the critical viscosity parameter that allows global accretion solutions including shocks. We estimate the energy dissipation at the PSC from where a part of the accreting matter can deflect as outflows and jets. We compare the maximum energy that could be extracted from the PSC and the observed radio luminosity values for several super-massive black hole sources and the observational implications of our present analysis are discussed.
description: 13 pages, 11 figures, accepted for publication in MNRAS
Double parton scattering in pair-production of $J/ψ$ mesons at the LHC revisited
Creators: name: Borschensky, Christoph
name: Kulesza, Anna
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Double parton scattering (DPS) is studied at the example of $J/ψ$ pair-production in the LHCb and ATLAS experiments of the Large Hadron Collider (LHC) at centre-of-mass energies of $\sqrt{S}=$ 7, 8, and 13 TeV. We report theoretical predictions delivered to the LHCb and ATLAS collaborations adjusted for the fiducial volumes of the corresponding measurements during Run I and provide new predictions at 13 TeV collision energy. It is shown that DPS can lead to noticeable contributions in the distributions of longitudinal variables of the di-$J/ψ$ system, especially at 13 TeV. The increased DPS rate in double $J/ψ$ production at high energies will open up more possibilities for the separation of single parton scattering (SPS) and DPS contributions in future studies.
description: 22 pages, 10 figures
The Land Surface Temperature Synergistic Processor in BEAM: A Prototype towards Sentinel-3
Creators: name: Ruescas, Ana Belen
name: Danne, Olaf
name: Fomferra, Norman
name: Brockmann, Carsten
Publisher: name: arXiv
Year: 2016
Subjects: subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: Land Surface Temperature (LST) is one of the key parameters in the physics of land-surface processes on regional and global scales, combining the results of all surface-atmosphere interactions and energy fluxes between the surface and the atmosphere. With the advent of the European Space Agency (ESA) Sentinel 3 (S3) satellite, accurate LST retrieval methodologies are being developed by exploiting the synergy between the Ocean and Land Colour Instrument (OLCI) and the Sea and Land Surface Temperature Radiometer (SLSTR). In this paper we explain the implementation in the Basic ENVISAT Toolbox for (A)ATSR and MERIS (BEAM) and the use of one LST algorithm developed in the framework of the Synergistic Use of The Sentinel Missions For Estimating And Monitoring Land Surface Temperature (SEN4LST) project. The LST algorithm is based on the split-window technique with an explicit dependence on the surface emissivity. Performance of the methodology is assessed by using MEdium Resolution Imaging Spectrometer/Advanced Along-Track Scanning Radiometer (MERIS/AATSR) pairs, instruments with similar characteristics than OLCI/ SLSTR, respectively. The LST retrievals were properly validated against in situ data measured along one year (2011) in three test sites, and inter-compared to the standard AATSR level-2 product with satisfactory results. The algorithm is implemented in BEAM using as a basis the MERIS/AATSR Synergy Toolbox. Specific details about the processor validation can be found in the validation report of the SEN4LST project.
description: 14 pages, 7 figures, 3 tables
On the work of Rodriguez Hertz on rigidity in dynamics
Creators: name: Spatzier, Ralf
Publisher: name: arXiv
Year: 2016
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 37C15, 37C85, 37D20, 53C24

description: This paper is a survey about recent progress in measure rigidity and global rigidity of Anosov actions, and celebrates the profound contributions by Federico Rodriguez Hertz to rigidity in dynamical systems.
Wannier functions using a discrete variable representation for optical lattices
Creators: name: Paul, Saurabh
name: Tiesinga, Eite
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We propose a numerical method using the discrete variable representation (DVR) for constructing real-valued Wannier functions localized in a unit cell for both symmetric and asymmetric periodic potentials. We apply these results to finding Wannier functions for ultracold atoms trapped in laser-generated optical lattices. Following Kivelson \cite{kivelson_wannier_1982}, for a symmetric lattice with inversion symmetry, we construct Wannier functions as eigen states of the position operators $\hat x$, $\hat y$ and $\hat z$ restricted to single-particle Bloch functions belonging to one or more bands. To ensure that the Wannier functions are real-valued, we numerically obtain the band structure and real-valued eigen states using a uniform Fourier grid DVR. We then show by a comparison of tunneling energies, that the Wannier functions are accurate for both inversion symmetric and asymmetric potentials to better than ten significant digits when using double-precision arithmetic. The calculations are performed for an optical lattice with double-wells per unit cell with tunable asymmetry along the $x$ axis and a single sinusoidal potential along the perpendicular directions. Localized functions at the two potential minima within each unit cell are similarly constructed, but using a superposition of single-particle solutions from the two lowest bands. We finally use these localized basis functions to determine the two-body interaction energies in the Bose-Hubbard (BH) model, and show the dependence of these energies on lattice asymmetry.
description: 9 pages, 8 figures
Persistent organic pollutants in ambient air – sources, patterns, and environmental behaviour
Creators: name: Graf, Carola
Publisher: name: Lancaster University
Year: 2023

description: Long-term air monitoring datasets are needed for persistent organic pollutants (POPs) to assess the effectiveness of source abatement measures and the factors controlling ambient levels, and to provide governments, regulators, and researchers with valuable information on emission/source controls and on the effectiveness of international chemicals regulation such as the Stockholm Convention and UN/ECE Protocol on POPs. These data can be provided by active or passive air sampling. The UK Toxic Organic Micro Pollutants (TOMPs) Network, using high-volume active air samplers, has demonstrated the constant decline in UK air concentrations for polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polybrominated diphenyl ethers (PBDEs) since 1991, in accordance with emission estimates. For a latitudinal passive ambient air sampling transect from the south of England to the north of Norway established in 1994, which had reported several years of decreasing PCB air concentrations previously, increased levels were observed between 2008 and 2016. The reasons for this could include local sources, effects of climate change, and impact of polluted air masses from Eastern Europe. In contrast, PBDE concentrations have decreased since 2000 in line with expectations. Furthermore, seasonal patterns for PCB and PBDE concentrations in UK ambient air are discussed. PCBs generally showed a summer > winter pattern, while ƩPBDE concentrations were distributed over a range of congeners with more uniform concentrations but greater differences in seasonal patterns, thus their overall seasonality was characterized by these contrasting patterns. In addition to long-term trends and regular seasonal variations, short-term emission events like the UK ‘Bonfire Night’, where increased PBDE concentrations possibly stemming from ‘backyard burning’ were observed, were shown to impact POPs concentrations in ambient air. In order to overcome some limitations of current air sampling methods, two potential improvements were evaluated and recommended: the addition of XAD® pods in standard active air samplers, and the addition of monofluorinated PCBs to the range of performance reference compounds for passive air sampling.
ZFIRE: The Kinematics of Star-Forming Galaxies as a Function of Environment at z~2
Creators: name: Alcorn, Leo Y.
name: Tran, Kim-Vy H.
name: Kacprzak, Glenn G.
name: Nanayakkara, Themiya
name: Straatman, Caroline
name: Yuan, Tiantian
name: Allen, Rebecca J.
name: Cowley, Michael
name: Davé, Romeel
name: Glazebrook, Karl
name: Kewley, Lisa J.
name: Labbé, Ivo
name: Quadri, Ryan
name: Spitler, Lee R.
name: Tomczak, Adam
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We perform a kinematic analysis of galaxies at $z\sim2$ in the COSMOS legacy field using near-infrared (NIR) spectroscopy from Keck/MOSFIRE as part of the ZFIRE survey. Our sample consists of 75 Ks-band selected star-forming galaxies from the ZFOURGE survey with stellar masses ranging from log(M$_{\star}$/M$_{\odot}$)$=9.0-11.0$, 28 of which are members of a known overdensity at $z=2.095$. We measure H$α$ emission-line integrated velocity dispersions ($σ_{\rm int}$) from 50$-$230 km s$^{-1}$, consistent with other emission-line studies of $z\sim2$ field galaxies. From these data we estimate virial, stellar, and gas masses and derive correlations between these properties for cluster and field galaxies at $z\sim2$. We find evidence that baryons dominate within the central effective radius. However, we find no statistically significant differences between the cluster and the field, and conclude that the kinematics of star-forming galaxies at $z\sim2$ are not significantly different between the cluster and field environments.
description: 6 pages, 4 figures, accepted for publication in ApJL
A Wellspring in the Desert: Exploring a new model for intercultural peacebuilding in Israel-Palestine
Creators: name: Paasche-Orlow, Lev
Publisher: name: University of Chicago
Year: 2022
Subjects: subject: Arabic, Palestinian, learning, university, Jewish, peacebuilding, Hebrew, peer-mentorship, shared society, intercultural

description: This research delves into a new model for P2P peacebuilding introduced by the non-profit Ma’ayan Bamidbar, “A Wellspring in the Desert”. Ma’ayan Bamidbar aims to build inter cultural connections between Palestinian and Jewish university students by facilitating semester or year-long, one-on-one language learning partnerships. Using data from semi-structured interviews with Jewish program alumni and coordinators I hypothesize that Ma’ayan Bamidbar’s particular structure for individual personal engagement, centered on language and learning, generates empathy in Jewish participants for their Palestinian peers. The impact of participating continues post participation as the program is integrated into the student’s daily lives. Through personal relationships, Ma’ayan Bamidbar constructs a collective identity between university students focused on a belief in humanity and shared society. This collective identity is central to the national movement for shared society making Ma’ayan Bamidbar an effective catalyst for activism and social change.
On $c_2$ invariants of 4-regular Feynman graphs
Creators: name: Doryn, Dmitry
Publisher: name: arXiv
Year: 2016
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14G05, 81Q30

description: The obstruction for application of effective techniques like denominator reduction for the computation of the $c_2$ invariant of Feynman graphs in general is the absence of a 3-valent vertex for the initial steps. In this paper such a formula for a 4-valent vertex is derived. The formula allows to compute the $c_2$ invariant of new graphs, for instance, 4-regular graphs with small loop number.
description: 22 pages, 2 figures
Synchrotron radiation from a curved plasma channel laser wakefield accelerator
Creators: name: Palastro, J. P.
name: Kaganovich, D.
name: Hafizi, B.
name: Chen, Y. -H.
name: Johnson, L. A.
name: Penano, J. R.
name: Helle, M. H.
name: Mamonau, A. A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Accelerator Physics (physics.acc-ph)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: A laser pulse guided in a curved plasma channel can excite wakefields that steer electrons along an arched trajectory. As the electrons are accelerated along the curved channel, they emit synchrotron radiation. We present simple analytical models and simulations examining laser pulse guiding, wakefield generation, electron steering, and synchrotron emission in curved plasma channels. For experimentally realizable parameters, a ~2 GeV electron emits 0.1 photons per cm with an average photon energy of multiple keV.
Towards an Automatic Easy-to-Read Adaptation of Morphological Features in Spanish Texts
Creators: name: Suárez-Figueroa, Mari Carmen
name: Diab, Isam
name: González, Álvaro
name: Rivero-Espinosa, Jesica
Publisher: name: Zenodo
Year: 2023
Subjects: Easy-to-Read
Cognitive Accessibility
User Study
User-based Evaluation

description: This record presents the supplementary information of the paper entitled "Towards an Automatic Easy-to-Read Adaptation
 of Morphological Features in Spanish Texts": Documents related to the user study (Section 3): 2 PDF files that show the questionnaires we used in the user study described in the paper. 2 CSV documents that contains the responses obtained in the user study performed in the context of the paper. Documents related to the user-based evaluation (Section 4.3): 2 PDF files that show the questionnaires we used in the user-based evaluation described in the paper. 2 CSV documents that contains the responses obtained in the user-based evaluation performed in the context of the paper. 2 PDF files that presents the report generated by Google Forms with the responses to the questionnaires.
BIMERR Sensor Data ontology
Creators: name: Feria, Serge Chávez
name: María Poveda-Villalón;
name: García-Castro, Raúl
Publisher: name: Zenodo
Year: 2022
Subjects: semantics
ontology
sensor data

description: The Sensor Data ontology has been developed to represent measurements generated by sensors located inside building spaces. It also includes specific concepts and properties to model sensors and actuators records that follow the SenML standard. This model allows the representation of resolved and unresolved records if required. (Check SenML standard for more details: https://tools.ietf.org/html/rfc8428#)
Perfect state transfer by means of discrete-time quantum walk search algorithms on highly symmetric graphs
Creators: name: Stefanak, Martin
name: Skoupy, Stanislav
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Perfect state transfer between two marked vertices of a graph by means of discrete-time quantum walk is analyzed. We consider the quantum walk search algorithm with two marked vertices, sender and receiver. It is shown by explicit calculation that for the coined quantum walks on star graph and complete graph with self-loops perfect state transfer between the sender and receiver vertex is achieved for arbitrary number of vertices $N$ in $O(\sqrt{N})$ steps of the walk. Finally, we show that Szegedy's walk with queries on complete graph allows for state transfer with unit fidelity in the limit of large $N$.
Herding in the USDA International Baseline Projections
Creators: name: Chandio, Rabail
name: Katchova, Ani
name: Chandio, Rabail
name: Katchova, Ani
Publisher: name: Unknown
Year: 2022
Subjects: Agricultural and Food Policy
International Relations/Trade

description: USDA’s annual Agricultural Baseline Projections contribute significantly to agricultural policy in the United States, and hence their accuracy is vital. The baseline projections present a neutral policy scenario assuming a specific macroeconomic situation and allow the analyses of alternative policies and their micro and macroeconomic impacts in the United States. We investigate the trends and heterogeneity in the incidence of bias in the USDA International Baseline Projection reports from 2002 to 2021. The evaluation of bias as it varies geographically, temporally, and by crop-variable allows us to make inferential judgments about the sources of this bias. First, we use the dynamic time warping algorithm to examine whether experts tend to group together the projections for certain crops across different countries, producing similar projection trends. We find that projection series for all countries in the sample are correlated with the United States in their trends. Second, we compute the bias in projections and decompose it by projection horizon. Third, we assess whether the bias is higher across crops or across countries with more substantial evidence for grouping behavior and find that for soybeans imports, soybeans ending stocks, and wheat area harvested, similarity in projection trends with the United States lowers the bias while for most other crop-variables it increases it. This suggests that the projections for our sample countries are unnecessarily made to follow similar trends to the United States projections which proves to be a bias inducing choice in most cases.
Representation learning for very short texts using weighted word embedding aggregation
Creators: name: De Boom, Cedric
name: Van Canneyt, Steven
name: Demeester, Thomas
name: Dhoedt, Bart
Publisher: name: arXiv
Year: 2016
Subjects: subject: Information Retrieval (cs.IR)
subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: Short text messages such as tweets are very noisy and sparse in their use of vocabulary. Traditional textual representations, such as tf-idf, have difficulty grasping the semantic meaning of such texts, which is important in applications such as event detection, opinion mining, news recommendation, etc. We constructed a method based on semantic word embeddings and frequency information to arrive at low-dimensional representations for short texts designed to capture semantic similarity. For this purpose we designed a weight-based model and a learning procedure based on a novel median-based loss function. This paper discusses the details of our model and the optimization methods, together with the experimental results on both Wikipedia and Twitter data. We find that our method outperforms the baseline approaches in the experiments, and that it generalizes well on different word embeddings without retraining. Our method is therefore capable of retaining most of the semantic information in the text, and is applicable out-of-the-box.
description: 8 pages, 3 figures, 2 tables, appears in Pattern Recognition Letters
Effect of Energy Polydispersity on the Nature of Lennard-Jones Liquids
Creators: name: Ingebrigtsen, Trond S.
name: Tanaka, Hajime
Publisher: name: arXiv
Year: 2016
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: In the companion paper [T. S. Ingebrigtsen and H. Tanaka, J. Phys. Chem. B 119, 11052 (2015)] the effect of size polydispersity on the nature of Lennard-Jones (LJ) liquids, which represent most molecular liquids without hydrogen bonds, was studied. More specifically, it was shown that even highly size polydisperse LJ liquids are Roskilde-simple (RS) liquids. RS liquids are liquids with strong correlation between constant volume equilibrium fluctuations of virial and potential energy and are simpler than other types of liquids. Moreover, it was shown that size polydisperse LJ liquids have isomorphs to a good approximation. Isomorphs are curves in the phase diagram of RS liquids along which structure, dynamics, and some thermodynamic quantities are invariant in dimensionless (reduced) units. In this paper, we study the effect of energy polydispersity on the nature of LJ liquids. We show that energy polydisperse LJ liquids are RS liquids. However, a tendency of particle segregation which increases with the degree of polydispersity leads to a loss of strong virial-potential energy correlation, but is mitigated with increasing temperature and/or density. Isomorphs are a good approximation also for energy polydisperse LJ liquids, although particle-resolved quantities display a somewhat poorer scaling compared to the mean quantities along the isomorph.
description: comments are welcome
Collective Robot Reinforcement Learning with Distributed Asynchronous Guided Policy Search
Creators: name: Yahya, Ali
name: Li, Adrian
name: Kalakrishnan, Mrinal
name: Chebotar, Yevgen
name: Levine, Sergey
Publisher: name: arXiv
Year: 2016
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences
subject: I.2.6; I.2.9

description: In principle, reinforcement learning and policy search methods can enable robots to learn highly complex and general skills that may allow them to function amid the complexity and diversity of the real world. However, training a policy that generalizes well across a wide range of real-world conditions requires far greater quantity and diversity of experience than is practical to collect with a single robot. Fortunately, it is possible for multiple robots to share their experience with one another, and thereby, learn a policy collectively. In this work, we explore distributed and asynchronous policy learning as a means to achieve generalization and improved training times on challenging, real-world manipulation tasks. We propose a distributed and asynchronous version of Guided Policy Search and use it to demonstrate collective policy learning on a vision-based door opening task using four robots. We show that it achieves better generalization, utilization, and training times than the single robot alternative.
description: Submitted to the IEEE International Conference on Robotics and Automation 2017
title: Στρεπτική αντοχή ελαφρά οπλισμένης πλακοδοκού από σκυρόδεμα
title: Torsional strength of slightly rc t-beam
titleType: AlternativeTitle
Creators: name: Καρπούζος, Ορφέας
Publisher: name: Πανεπιστήμιο Δυτικής Αττικής
Year: 2023
Subjects: Πλακοδοκοί
Στρέψη
Ροπή στρέψης
Διατομή Τ
Σκυρόδεμα

description: Αντικείμενο της συγκεκριμένης εργασίας είναι η εύρεση αντοχής ελαφρά οπλισμένης πλακοδοκού διατομής Τ από σκυρόδεμα, που καταπονείται σε στρέψη. Προκειμένου να επιτευχθεί το παραπάνω, θα χρειαστεί να γίνουν πειράματα πλακοδοκών οπλισμένου σκυροδέματος με εμβαδόν χάλυβα που θα προκύψει από κατάλληλους υπολογισμούς, οι οποίοι θα πρέπει να ανταποκρίνονται στα αποτελέσματα των δοκιμίων ,που θα καταπονηθούν με μία έκκεντρη φόρτιση σε πρέσα κάμψης δοκιμίων. Για την πραγματοποίηση του συγκεκριμένου θέματος κατασκευάστηκαν πλακοδοκοί στο Εργαστήριο Οπλισμένου Σκυροδέματος του Πανεπιστημίου Δυτικής Αττικής.