cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Development of KI-TWPAs for the DARTWARS project
Creators: name: Ahrens, Felix
name: Ferri, Elena
name: Avallone, Guerino
name: Barone, Carlo
name: Borghesi, Matteo
name: Callegaro, Luca
name: Carapella, Giovanni
name: Caricato, Anna Paola
name: Carusotto, Iacopo
name: Cian, Alessandro
name: D'Elia, Alessandro
name: Di Gioacchino, Daniele
name: Enrico, Emanuele
name: Falferi, Paolo
name: Fasolo, Luca
name: Faverzani, Marco
name: Filatrella, Giovanni
name: Gatti, Claudio
name: Giachero, Andrea
name: Giubertoni, Damiano
name: Granata, Veronica
name: Guarcello, Claudio
name: Labranca, Danilo
name: Leo, Angelo
name: Ligi, Carlo
name: Maccarrone, Giovanni
name: Mantegazzini, Federica
name: Margesin, Benno
name: Maruccio, Giuseppe
name: Mezzena, Renato
name: Monteduro, Anna Grazia
name: Moretti, Roberto
name: Nucciotti, Angelo
name: Oberto, Luca
name: Origo, Luca
name: Pagano, Sergio
name: Piedjou, Alex Stephane
name: Piersanti, Luca
name: Rettaroli, Alessio
name: Rizzato, Silvia
name: Tocci, Simone
name: Vinante, Andrea
name: Zannoni, Mario
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Noise at the quantum limit over a broad bandwidth is a fundamental requirement for future cryogenic experiments for neutrino mass measurements, dark matter searches and Cosmic Microwave Background (CMB) measurements as well as for fast high-fidelity read-out of superconducting qubits. In the last years, Josephson Parametric Amplifiers (JPA) have demonstrated noise levels close to the quantum limit, but due to their narrow bandwidth, only few detectors or qubits per line can be read out in parallel. An alternative and innovative solution is based on superconducting parametric amplification exploiting the travelling-wave concept. Within the DARTWARS (Detector Array Readout with Travelling Wave AmplifieRS) project, we develop Kinetic Inductance Travelling-Wave Parametric Amplifiers (KI-TWPAs) for low temperature detectors and qubit read-out. KI-TWPAs are typically operated in a threewave mixing (3WM) mode and are characterised by a high gain, a high saturation power, a large amplification bandwidth and nearly quantum limited noise performance. The goal of the DARTWARS project is to optimise the KI-TWPA design, explore new materials, and investigate alternative fabrication processes in order to enhance the overall performance of the amplifier. In this contribution we present the advancements made by the DARTWARS collaboration to produce a working prototype of a KI-TWPA, from the fabrication to the characterisation.
Reconstruction, localisation, and segmentation in medical images
Creators: name: Alansary, Amir
Publisher: name: Imperial College London
Year: 2018

description: Medical imaging plays a crucial role for identifying a medical condition, therapeutic response, disease level or the chance of developing a future complication. This thesis proposes robust and fully-automatic medical imaging methods that can assist doctors in their clinical decision making. In particular, it contributes to the main components of the medical imaging pipeline: image acquisition, reconstruction, and analysis. A novel approach is proposed for motion correction and reconstruction in foetal MRI. Whereas scanned images suffer from inter-slice motion artefacts because of the unconstrained foetal movements. The proposed method explores a new reconstruction paradigm that splits the 3D input image into overlapping patches. This enables conventional reconstruction methods to compensate for non-rigid deformations and reconstruct the whole uterus. Another new method is proposed for automatic foetal brain localisation, which is essential for assessing the brain development and maturation in foetal MRI. The proposed method uses superpixel graphs to train a random forest classifier, which allows to efficiently extract 3D global features instead of 2D local features. Results show high brain detection accuracy, without the need of any landmarks or prior information such as the gestational age of the foetus. Automatic segmentation of the placenta is more challenging than brain segmentation because of its variability in position, shape and appearance. The proposed method adopts a multi-pathway convolutional neural network to efficiently captures both local and global contextual information. The predicted output is then refined using a condition random field to regularise outliers. This thesis also proposes and evaluates reinforcement learning based methods for the detection of anatomical landmarks, which is an important step for a wide range of applications in medical image analysis. Manual annotation of such landmarks is a tedious task and prone to observer errors. Fixed-scale and multi-scale search strategies are evaluated on three different datasets: foetal ultrasound, brain and cardiac MRI. The evaluation results outperform current supervised and other reinforcement learning state-of-the-art methods. Finally, a novel approach is proposed for automatic view planning using intelligent artificial agents to mimic the navigation process towards the target plane. Similar to the landmark agents, view planning agents learn to find the target plane iteratively using reinforcement learning. The experiments show that view planning agents can detect different standard planes from brain and cardiac MRI with state-of-the-art accuracy in a very short time.
SNe Kicks in Hierarchical Triple Systems
Creators: name: Lu, Cicero X.
name: Naoz, Smadar
Publisher: name: arXiv
Year: 2018
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Most massive stars, if not all, are in binary configuration or higher multiples. These massive stars undergo supernova explosions and end their lives as either black holes or neutron stars. Recent observations have suggested that neutron stars and perhaps even black holes receive large velocity kicks at birth. Such natal kicks and the sudden mass loss can significantly alter the orbital configuration of the system. Here we derive general analytical expressions that describe the effects of natal kicks in binaries on hierarchical triple systems. We explore several proof-of-concept applications such as black hole and neutron stars binaries and X-ray binaries with either stellar or Supermassive Black Hole (SMBH) companions on a wide orbit. Kicks can disrupt the hierarchical configuration, although it is harder to escape the potential well of an SMBH. Some binary systems do escape the SMBH system resulting in hyper-velocity binary system. Furthermore, kicks can result in increasing or decreasing the orbital separations. Decreasing the orbital separation may have significant consequences in these astrophysical systems. For example, shrinking the separation post-supernova kick can lead to the shrinking of an inner compact binary that then may merge via Gravitational Wave (GW) emission. This process yields a supernova that is shortly followed by a possible GW-LIGO event. Interestingly, we find that the natal kick can result in shrinking the outer orbit, and the binary may cross the tertiary Roche limit, breaking up the inner binary. Thus, in the case of SMBH companion, this process can lead to either a tidal disruption event or a GW-LISA detection event with a supernova precursor.
description: 19 pages, 16 figures, 3 tables, accepted to MNRAS, fixed incorrect figure 8 on LISA detection limit
title: ADCO, Abbaye de Cîteaux, 'Transcrits des titres de la layette marquée QQ, 1er cartable, liasses 1, 2 et 3' / Cartulaire d'Ouges (XVIIIe siècle, 2e moitié), Cart. 196 (11 H 938), f. 0069
Creators: name: de la Côte d'Or, Archives départementales
name: Petot, Frédéric
name: Archives Départementales De La Côte-D'Or
name: Petot, Frédérique
name: Projet CBMA
name: CG21/F.PETOT/2017
Publisher: name: NAKALA - https://nakala.fr (Huma-Num - CNRS)
publisherIdentifier: https://ror.org/04ces3204
publisherIdentifierScheme: ROR
Year: 2020
Subjects: subject: cartulaire
subject: LaMOP
subject: Laboratoire de Médiévistique Occidentale de Paris
subject: Corpus Burgundiae Medii Aevi
subject: Chartes de la Bourgogne du Moyen Âge

description: Abbaye de Cîteaux, 'Transcrits des titres de la layette marquée QQ, 1er cartable, liasses 1, 2 et 3' / Cartulaire d'Ouges (XVIIIe siècle, 2e moitié), Archives départementales de la Côte-d'Or, Cart. 196 (11 H 938), Numérisation en mode image.
description: Relation: http://www.cbma-project.eu/
description: Bibliographic citation: Abbaye de Cîteaux, 'Transcrits des titres de la layette marquée QQ, 1er cartable, liasses 1, 2 et 3' / Cartulaire d'Ouges (XVIIIe siècle, 2e moitié), Archives départementales de la Côte-d'Or, Cart. 196 (11 H 938), f. 0069, in Projet CBMA - Corpus Burgundiae Medii Aevi [Ressource en ligne], https:// manuscrits.cbma-project.eu/
description: Provenance: http://www.wikidata.org/entity/Q843261
description: Provenance: abbaye de Cîteaux
description: Provenance: https://www.geonames.org/3024876
description: Provenance: http://www.idref.fr/030974844/id
description: Provenance: https://catalogue.bnf.fr/ark:/12148/cb12228351v
Black Community Educational Leaders: Knowledge Production Influence in Education
Creators: name: Trinisia Brooks
Publisher: name: Unknown
Year: 2024

description: While the structural inequities leading to the school-to-prison pipeline (STPP) were well documented in scholarly literature, there was surprisingly little research that centered Black Community Educational Leaders' (BCEL) knowledge and wisdom relative to this injustice. To offer a critical perspective on racial disparities directly targeting Black youth, in a qualitative study this research used storytelling as the methodology to counter the normative (or status quo) way of thinking about Black youth and their lived experiences. Eleven Black Community Educational Leaders who met the established criterion were nominated by members in the local community to participate in a critical case study. The research demonstrated how BCEL
possessed profound wisdom to confront and address the root causes of racialized exclusionary practices and structural inequities that affected Black youth in schools and communities. The context of this study focused primarily in the Promise Neighborhood. Historically these were impoverished communities with underperforming schools. For this research, racialized exclusionary practices and structural inequities were viewed through the lens of Black student removal from the classroom that potentially led to a culmination of negative disparate academic and social outcomes. Core findings revealed critical perspectives and wisdom from BCEL about the extensive improvements needed in education and community spaces. Specifically, this research acknowledged historical perspectives and highlighted the importance of high-quality education and equitable opportunities for Black youth.
Prompt and Delayed High-Energy Emission from Cosmological Gamma-Ray Bursts
Creators: name: Boettcher, M.
name: Dermer, C. D.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In the cosmological blast-wave model for gamma ray bursts (GRBs), high energy (> 10 GeV) gamma-rays are produced either through Compton scattering of soft photons by ultrarelativistic electrons, or as a consequence of the acceleration of protons to ultrahigh energies. We describe the spectral and temporal characteristics of high energy gamma-rays produced by both mechanisms, and discuss how these processes can be distinguished through observations with low-threshold Cherenkov telescopes or GLAST. We propose that Compton scattering of starlight photons by blast wave electrons can produce delayed flares of GeV -- TeV radiation.
description: to appear in Proceedings of VERITAS Workshop on TeV Astrophysics of Extragalactic Sources, eds. M. Catanese, J. Quinn, T. Weekes
Cosmic dust fertilization of glacial prebiotic chemistry on early Earth
Creators: name: Walton, Craig R.
name: Rigley, Jessica K.
name: Lipp, Alexander
name: Law, Robert
name: Suttle, Martin D.
name: Schonbachler, Maria
name: Wyatt, Mark
name: Shorttle, Oliver
Publisher: name: arXiv
Year: 2024
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: Earth's surface is deficient in available forms of many elements considered limiting for prebiotic chemistry. In contrast, many extraterrestrial rocky objects are rich in these same elements. Limiting prebiotic ingredients may, therefore, have been delivered by exogenous material; however, the mechanisms by which exogeneous material may be reliably and non-destructively supplied to a planetary surface remains unclear. Today, the flux of extraterrestrial matter to Earth is dominated by fine-grained cosmic dust. Although this material is rarely discussed in a prebiotic context due to its delivery over a large surface area, concentrated cosmic dust deposits are known to form on Earth today due to the action of sedimentary processes. Here we combine empirical constraints on dust sedimentation with dynamical simulations of dust formation and planetary accretion to show that localized sedimentary deposits of cosmic dust could have accumulated in arid environments on early Earth, in particular glacial settings that today produce cryoconite sediments. Our results challenge the widely held assumption that cosmic dust is incapable of fertilizing prebiotic chemistry. Cosmic dust deposits may have plausibly formed on early Earth and acted to fertilize prebiotic chemistry.
description: 5 figures
Developing new routes to f-element heterometallic complexes
Creators: name: Hickson, James
Publisher: name: Imperial College London
Year: 2018

description: An introduction to the significance of f-elements and heterometallic complexes is presented in Chapter 1. Chapter 2 takes the redox active ligand 1,10-phenanthroline-5,6-dione (pd) and explores its rare earth chemistry. It also develops a modular route to the preparation of the ternary lanthanide complexes [Ln(hfac)3(N,N′-pd)] (Ln = Y, Sc, La. hfac = 1,1,1-5,5,5-hexafluroacetylacetonate). Chapter 3 takes these complexes in oxidative addition reactions with vanadocenes, and describes the preparation of the lanthanide-vanadium(IV) heterobimetallic complexes [Ln(hfac)3(N,N′-O,O′-pd)VCpR2] (Ln = Y, Sc, La. CpR = Cp, CpMe4), as well as their electronic structure using a range of spectroscopic techniques and DFT calculations. Chapter 4 builds on this chemistry by using cobaltocene; the reaction between pd and CoCp2 leads to the isolation and full characterisation of the first 1,10-phenanthroline-5,6-semiquinone (pd•-) species, [CoCp2]+[pd]•-, via one electron reduction. Chapter 5 details other attempts at the one electron reduction at pd using a range of transition metal precursors. The attempted synthesis of a potassium pd salt is also described. Chapter 6 investigates the electron transfer reactivity between YX3 (X = OTf, Cl, I, hfac) precursors, pd and ferrocene, as well as describing the synthesis of the heteroleptic complexes [Y(hfac)2(OTf)(thf)3] and [La(hfac)(κ-OTf)(thf)2]. Chapter 7 is a preliminary study of the reactivity between pd and organometallic Ln(II) precursors such as [{(N{SiMe3}2)2(thf)Y}2(μ-η2:η2-N2)] or LnI2 (Ln = Sm, Dy).
Probing the hard X-ray properties of high-redshift Radio-Quiet Quasars with ASCA
Creators: name: Vignali, C.
name: Comastri, A.
name: Cappi, M.
name: Palumbo, G. G. C.
name: Matsuoka, M.
name: Kubo, H.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: This paper reports the X-ray spectral analysis of 5 high-redshift (z \ge 2) radio-quiet quasars observed by ASCA. A simple power law continuum plus cold Galactic absorption model well fits all the spectra (tipically between $\sim$ 2-30 keV in the sources frame). Neither the X-ray spectral hardening, attributed to a reflection component and observed in Seyfert galaxies, nor the excess absorption previously detected in high-redshift radio-loud quasars, have been revealed. Only a marginal evidence of a neutral or mildly ionized FeKαline is found in one of the quasars. The average spectral slope in the observed 0.7--10 keV energy range, $ = 1.67 \pm{0.11}$ (dispersion $σ\sim 0.07$), appears to be flatter than that of low-z radio-quiet quasars ($Γ\simeq 1.9-2$) and slightly steeper, but consistent with $Γ$ = 1.61 \pm{0.04} (σ\sim 0.10)$ of high-z radio-loud quasars.
description: 9 pages, emulateapj style, plus 16 figures. Accepted for publication in the Astrophysical Journal
Well test analysis of shale gas wells
Creators: name: Kostyleva, Irina
Publisher: name: Imperial College London
Year: 2018

description: Shale gas reservoirs have received much attention in the last ten years with the development of stimulation techniques, namely massive hydraulic fracturing of horizontal wells. However, the processes taking place in these reservoirs during stimulation and production phases are not yet fully understood. Much of the research interest has been concentrated on decline curve analysis methods (for example, Stright and Gordon (1983)[96]), pore-scale description or forward modelling of pressure responses with the inclusion of pressure-dependent properties. The true challenge lies in explaining field data and understanding the dominating physical processes, and in particular permeability reduction, due to the fracture closures or conductivity impairments. The present research is concerned with analysis of field dynamic data of shale gas wells. A conceptual model was proposed and initially matched with two years of data from a number of Haynesville wells. Then three more years of production data were acquired, and the model was able to match the additional data. The model assumes three successive mechanisms governing well productivity deterioration: initially the matrix permeability declines, then the fracture conductivity is reduced, and finally, further latetime well productivity decline occurs which can be matched by introducing a pseudo-skin effect increasing linearly with time. These successive behaviours can be identified on a normalised rate versus cumulative production plot, where they are characterized by straight lines with distinct slopes. The conceptual model was represented in a 3D simulator by a single repetitive element corresponding to a section of a horizontal well with a single vertical fracture confined between the no-flow boundaries resulting from fracture interferences. The repetitive element includes two regions: a network of induced fractures around the well with enhanced permeability and an outer unfractured matrix with permeability values in the nano Darcy range. Permeability declines with pressure in both regions, according to a relationship based on core measurements in the matrix, and determined by history matching in the inner fractured region. Further productivity reduction at later times in some wells is accounted for with a pseudo-skin obtained by history matching. The direct application of conventional well test analysis and deconvolution methods to shale gas field data is not possible as rock properties are pressure-dependent and the problem is non-linear. Pseudo-time and pseudo-pressure functions were used to linearise the diffusivity equation, using the pressure-dependent properties obtained from history matching. Deconvolving them provided the derivative shape consistent with the responses expected from a multi-fractured horizontal well, thus providing an additional justification of the proposed approach and of the validity of the conceptual model developed in this study.
Gas Dynamics in the Barred Seyfert Galaxy NGC4151 - I. HI Streaming Shocks and Inflow Along the Bar
Creators: name: Mundell, C. G.
name: Shone, D. L.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present sensitive, high resolution observations of neutral hydrogen (HI) in the unusually gas-rich, oval distortion of the Seyfert galaxy NGC4151. The gas dynamics of the oval are found to be consistent with those of a kinematically weak bar, fully confirming previous suggestions for the presence of a fat bar, and, for the first time, individual gaseous features in the bar are spatially resolved. In particular, the two bright regions close to the leading edges of the bar in NGC4151 exhibit kinematics strikingly similar to the signature of bar shocks seen in gas-dynamical simulations, and demonstrate how strong the gaseous response may be even in such a weak bar potential. The residual velocity field, showing deviations from circular motion, is largely consistent with streaming in a bar potential, and, in addition, clearly shows that inflow is concentrated in narrow regions originating in the shocks. This inflow may represent an early stage in the fuelling process of the AGN. The presence and properties of the shocks in NGC4151 indicate that, in addition to the x_1 orbits, the family of x_2 orbits exist and are of significant extent in the bar of NGC4151, with gas streaming from the shocks making the transition between the two families. We therefore suggest that the circumnuclear ellipse, identified optically by previous authors and associated with gas flowing in x_2 orbits, has formed as a natural consequence of the gas flows in the bar without the requirement for a second, inner bar. Observations of HI were previously thought to be ill-suited to the study of bar shocks due to limitations in angular resolution and sensitivity. However, our observations show that, following recent instrumental enhancements, such measurements are now feasible, albeit at the limits of instrumental capability.
description: 7 pages, including 2 figures; accepted for publication in MNRAS
Double graph complex and characteristic classes of fibrations
Creators: name: Matsuyuki, Takahiro
Publisher: name: arXiv
Year: 2018
Subjects: subject: Algebraic Topology (math.AT)
subject: FOS: Mathematics
subject: 55R40

description: In this paper, we construct a double chain complex generated by certain graphs and a chain map from that to the Chevalley-Eilenberg double complex of the dgl of symplectic derivations on a free dgl. It is known that the target of the map is related to characteristic classes of fibrations. We can describe some characteristic classes of fibrations whose fiber is a 1-punctured even-dimensional manifold by linear combinations of graphs though the cohomology of the dgl of derivations.
description: 19 pages, 7 figures
Interferometric Observations of Redshifted Molecular Absorption toward Gravitational Lenses
Creators: name: Menten, Karl M.
name: Carilli, Christopher L.
name: Reid, Mark J.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have made radio- and millimeter-wavelength interferometric observations of a variety of molecular absorption lines toward the gravitational lens systems B0218+357 and PKS1830-211. The absorption occurs in the lensing galaxies at redshifts of 0.685 and 0.89, respectively. The high spatial resolution of our VLA and VLBA observations allows imaging of the background continuum emission and the absorption distribution. Our multi-transition studies yield estimates of the cosmic microwave background temperature at z = 0.89 and determinations of molecular and isotopic abundance ratios, which allow meaningful comparisons with Galactic molecular clouds.
description: postscript file
title: 01_1155
Creators: name: Wesley Baldwin, John
name: Baldwin, John W.
Publisher: name: NAKALA - https://nakala.fr (Huma-Num - CNRS)
publisherIdentifier: https://ror.org/04ces3204
publisherIdentifierScheme: ROR
Year: 2018
Subjects: subject: LaMOP
subject: Laboratoire de Médiévistique Occidentale de Paris

description: L'ensemble de ces notes ont été crée par John Baldwin lors d'une de ses premières périodes de résidence à Paris. Ces documents comprennent tous les magistri qu’il avait pu rencontrer dans ses sources. Aux XIIème et XIIIème siècles, les universités n'existant pas encore, le titre de magister s'il évoque certainement une compétence n'est pas rattaché de façon systématique au passage par les écoles. De surcroît, les magistris sont le plus souvent désignés par leur seul prénom. La lecture de ces données est donc difficile et suppose un long travail pour tenter d'identifier un individu auquel on pourrait rattacher plusieurs mentions. John Baldwin avait donc renoncé à utiliser ces données pour donner un prolongement à sa magnifique étude sur les gradués d'université et leur emploi par les Capétiens et les Plantagenêts. Néanmoins, il a conservé ces données et elles sont potentiellement très utile dans le cadre de Studium, comme le sont toutes les mentions dans les volumes des Fasti Ecclesiae Gallicanae de chanoines portant ce titre de magister sans autres précisions. L'ampleur des dépouillements rend ces données très utiles et nous devons une grande reconnaissance à John Baldwin pour avoir pris la peine de faire photocopier ses fiches et de nous les avoir transmises amicalement.
Les données ainsi que les images des fiches sont accessibles sur le site Internet à l'adresse suivante : http://studium-baldwin.lamop.fr/.
Les transcriptions des fiches ont été effectuées par des étudiants de Paris 1 Panthéon - Sorbonne mais elles n'ont pas été corrigées par la suite.
description: Relation: https://lamop.hypotheses.org/
High Redshift HI 21cm Absorption toward Red Quasars
Creators: name: Carilli, C. L.
name: Menten, Karl M.
name: Moore, C. P.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have searched for redshifted absorption in the 21 cm line of neutral hydrogen toward `red quasars', which are extragalactic radio sources with a steep spectral drop between optical and infrared wavelengths. The success rate for detecting HI 21cm absorption toward a representative sample of such sources is 80%. This compares to the much lower success rate of 11% for detecting HI 21cm absorption associated with optically selected Mg II absorption line systems. The large neutral hydrogen column densities seen toward red quasars supports the hypothesis that these sources are reddened by dust, as opposed to having an intrinsically red spectrum due to the AGN emission mechanism. The lower limits to the spin temperatures for the neutral hydrogen are between 50 K and 1000 K, assuming a Galactic dust-to-gas ratio. We consider the question of biases in optically selected samples of quasars due to dust obscuration. The data on the red quasar sub-sample support the models of Fall and Pei for dust obscuration by damped Ly alpha absorption line systems, and suggest that: (i) there may be a significant, but not dominant, population of quasars missing from optically selected samples due to dust obscuration, perhaps as high as 20% at the POSS limit for an optical sample with a redshift distribution similar to the 1 Jy, flat spectrum quasar sample, and (ii) optically selected samples may miss about half the high column density quasar absorption line systems.
description: postscript file
Low Luminosity States of the Black Hole Candidate GX~339--4. II. Timing Analysis
Creators: name: Nowak, Michael A.
name: Wilms, Joern
name: Dove, James B.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Here we present timing analysis of a set of eight Rossi X-ray Timing Explorer (RXTE) observations of the black hole candidate GX 339-4 that were taken during its hard/low state. On long time scales, the RXTE All Sky Monitor data reveal evidence of a 240 day periodicity, comparable to timescales expected from warped, precessing accretion disks. On short timescales all observations save one show evidence of a persistent f approximately equal to 0.3 Hz QPO. The broad band (10^{-3}-10^2 Hz) power appears to be dominated by two independent processes that can be modeled as very broad Lorentzians with Q approximately less than 1. The coherence function between soft and hard photon variability shows that if these are truly independent processes, then they are individually coherent, but they are incoherent with one another. This is evidenced by the fact that the coherence function between the hard and soft variability is near unity between 0.005-10 Hz but shows evidence of a dip at f approximately equal to 1 Hz. This is the region of overlap between the broad Lorentzian fits to the PSD. Similar to Cyg X-1, the coherence also drops dramatically at frequencies approximately greater than 10 Hz. Also similar to Cyg X-1, the hard photon variability is seen to lag the soft photon variability with the lag time increasing with decreasing Fourier frequency. The magnitude of this time lag appears to be positively correlated with the flux of GX 339-4. We discuss all of these observations in light of current theoretical models of both black hole spectra and temporal variability.
description: To Appear in the AStrophysical Journal
On the Indeterministic Nature of Star Formation on the Cloud Scale
Creators: name: Geen, Sam
name: Watson, Stuart K.
name: Rosdahl, Joakim
name: Bieri, Rebekka
name: Klessen, Ralf S.
name: Hennebelle, Patrick
Publisher: name: arXiv
Year: 2018
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Molecular clouds are turbulent structures whose star formation efficiency (SFE) is strongly affected by internal stellar feedback processes. In this paper we determine how sensitive the SFE of molecular clouds is to randomised inputs in the star formation feedback loop, and to what extent relationships between emergent cloud properties and the SFE can be recovered. We introduce the yule suite of 26 radiative magnetohydrodynamic (RMHD) simulations of a 10,000 solar mass cloud similar to those in the solar neighbourhood. We use the same initial global properties in every simulation but vary the initial mass function (IMF) sampling and initial cloud velocity structure. The final SFE lies between 6 and 23 percent when either of these parameters are changed. We use Bayesian mixed-effects models to uncover trends in the SFE. The number of photons emitted early in the cluster's life and the length of the cloud provide are the strongest predictors of the SFE. The HII regions evolve following an analytic model of expansion into a roughly isothermal density field. The more efficient feedback is at evaporating the cloud, the less the star cluster is dispersed. We argue that this is because if the gas is evaporated slowly, the stars are dragged outwards towards surviving gas clumps due to the gravitational attraction between the stars and gas. While star formation and feedback efficiencies are dependent on nonlinear processes, statistical models describing cloud-scale processes can be constructed.
description: 24 pages, 16 figures, 6 tables. Accepted to MNRAS, version updated with published title
Suitability of a lumped rainfall–runoff model for flashy tropical watersheds in New Caledonia
Creators: name: Térence Desclaux
name: Lemonnier, Hugues
name: Genthon, Pierre
name: Benoit Soulard
name: Gendre, Romain Le
Publisher: name: Taylor & Francis
Year: 2018
Subjects: subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Science Policy

description: The GR4H lumped hourly rainfall–runoff model was assessed for its integration in a ridge-to-reef modelling framework. Particular attention was paid to rainfall representation, robustness of parameter estimates and ability to reproduce the main runoff features. The study was conducted in four tropical mountainous watersheds in New Caledonia, which are exposed to intense rainfall events, large annual climatic variations triggered by El Niño oscillation, and wildfires. The inverse distance and elevation weighting algorithm outperformed other classical rainfall interpolation methods under data-limited conditions. The time span of data needed for robust calibration was site specific and varied from 6–7 years to 10 years, which may be linked to El Niño events and to wildfires. With sufficient data, simulation quality was equivalent during the calibration and validation periods. The GR4H model was generally able to simulate both flash floods and large annual variations. The model was more reliable when simulating wet years and watersheds not subject to land-cover changes.
A semianalytical model for the observational properties of the dominant carbon species at different metallicities
Creators: name: Bolatto, Alberto D.
name: Jackson, James M.
name: Ingalls, James G.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a simple, semianalytical approach to compute the line emission of C+, C and CO in Photodissociation Regions of varying metallicity that depends on very few parameters and naturally incorporates the clumpiness of the interstellar medium into the calculations. We use it to study the dependence of the I_[C II]/I_CO and I_[C I]/I_CO line ratios on the metallicity. We show how to modify it to include the effects of density and radiation field, and we have compared it with observational data. We find that the model explains the observed trend of enhanced [C II]/CO line ratio with decreasing metallicity as the natural result of the augmented fraction of photodissociated gas in a clump. We show that enhanced [C II]/CO ratios can be produced by lowering the upper limit of the clump size distribution, as may happen in 30 Doradus. We also find that the available data favors a [C I]/CO intensity ratio essentially independent of metallicity, albeit the paucity of observations does not exclude other possibilities. This is difficult to understand if most of the C is produced by UV photons as is the case with C+. Finally, we study the prediction of the model for the trend of the X_CO factor with metallicity. Comparison with previous observational studies yields good agreement.
description: 28 pages, 1 table, 7 Postscript figures, to appear in ApJ vol. 513, March 1999
Cosmic Histories of Stars, Gas, Heavy Elements, and Dust
Creators: name: Pei, Yichuan C.
name: Fall, S. Michael
name: Hauser, Michael G.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a set of coupled equations that relate the stellar, gaseous, chemical, and radiation constituents of the universe averaged over the whole galaxy population. Using as input the available data from quasar absorption-line surveys, optical imaging and redshift surveys, and the COBE DIRBE and FIRAS extragalactic infrared background measurements, we obtain solutions for the cosmic histories of stars, interstellar gas, heavy elements, dust, and radiation from stars and dust in galaxies. Our solutions reproduce remarkably well a wide variety of observations that were not used as input, including the integrated background light from galaxy counts, the optical and near-infrared emissivities from galaxy surveys, the local infrared emissivities from the IRAS survey, the mean abundance of heavy elements from surveys of damped Lyman-alpha systems, and the global star formation rates from H$α$ surveys and submillimeter observations. The solutions presented here suggest that the process of galaxy formation appears to have undergone an early period of substantial inflow to assemble interstellar gas at $z\gtrsim3$, a subsequent period of intense star formation and chemical enrichment at $1\lesssim z\lesssim3$, and a recent period of rapid decline in the gas content, star formation rate, optical stellar emissivity, and infrared dust emission at $z\lesssim1$. [abridged version]
description: 29 pages, ApJ in press, 10 Sept 99
Microstructural Materials Design via Deep Adversarial Learning Methodology
Creators: name: Yang, Zijiang
name: Li, Xiaolin
name: Brinson, L. Catherine
name: Choudhary, Alok N.
name: Chen, Wei
name: Agrawal, Ankit
Publisher: name: arXiv
Year: 2018
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Identifying the key microstructure representations is crucial for Computational Materials Design (CMD). However, existing microstructure characterization and reconstruction (MCR) techniques have limitations to be applied for materials design. Model-based MCR approaches do not have parameters that can serve as design variables, while MCR techniques that rely on dimension reduction tend to lose important microstructural information. In this work, we present a deep adversarial learning methodology that overcomes the limitations of existing MCR techniques. In the proposed methodology, generative adversarial networks (GAN) are trained to learn the mapping between latent variables and microstructures. Thereafter, the low-dimensional latent variables serve as design variables, and a Bayesian optimization framework is applied to obtain microstructures with desired material property. Due to the special design of the network architecture, the proposed methodology is able to identify the latent (design) variables with desired dimensionality, as well as minimize the information loss even for complex material microstructures. The validity of the proposed methodology is tested numerically on a synthetic microstructure dataset and its effectiveness for materials design is evaluated through a case study of optimizing optical performance for energy absorption. In addition, the scalability and transferability of proposed methodology are also demonstrated in this work. Specifically, the proposed methodology is scalable to generate arbitrary sized microstructures, and it can serve as a pre-trained model to improve the performance of a structure-property predictive model via transfer learning.
Characterisation of scandium- and iron-based GaN for high electron mobility transistors (HEMTs)
Creators: name: Pace, Simona
Publisher: name: Imperial College London
Year: 2018

description: III-nitrides have received increasing attention for high electron mobility transistors (HEMTs), due to their structural and electrical properties. The AlGaN/GaN structure shows large band offset and can generate 2D physically-confined channel at its interface. However, the performance of these devices is still limited by defects and impurities present in the structure. The former act as electron-traps in the channel, while the latter generate unwanted background carriers. To overcome this problem, scandium- and iron-based GaN materials have been proposed. When Sc is introduced in GaN, the c/a ratio decreases, and the band gap increases, leading to a new set of latticeparameter/ band-gap ratios. Such that, ScGaN/GaN may show large band offset with lower concentration of defects. Furthermore, the large piezoelectric constant of ScGaN should increase the carrier concentration in the channel. The background conductivity can be improved by introducing a (Fe,Ga)N layer at the GaN/sapphire interface. Fe introduces acceptor-like states in the band gap, leading to semi-insulating behaviour and improved channel-confinement. In this work the properties of GaN, ScGaN and (Fe,Ga)N grown using e-beam physical vapour deposition are investigated. The optimal Ga e-beam currents were found and epitaxial growth of GaN with relatively good quality achieved. ScGaN with increasing Sc concentration was also investigated. Large structural improvement was found for Sc 20%, possibly due to some relation between ScGaN and sapphire lattice parameters that reduces the stress in the thin film. In agreement with theoretical results, the band gap of Sc0.2Ga0.8N increases by 0.2 eV. Finally, the homogeneity and resistivity of (Fe,Ga)N were investigated. When Fe is 0.8% the structural quality is not affected while the resistivity increases to 108cm-2. For higher Fe concentration, Fe-rich nanocrystals become visible. However, no relation between inhomogeneity and electrical properties is observed and when Fe is 4.6% the resistivity further increases by 1 order of magnitude.
Disentangling the net: The socio-ecological dynamics of mosquito net fishing
Creators: name: Short, Rebecca
Publisher: name: Imperial College London
Year: 2018

description: The use of mosquito nets, largely handed out for free in efforts to control malaria, as fishing gear is anecdotally widespread. Mosquito net fishing (MNF) is condemned as a threat to food security and biodiversity due to its assumed but unsubstantiated ‘indiscriminate’ nature. A number of countries have banned the activity though no empirical investigation of the impacts or drivers of MNF exists. In this study I conduct a holistic investigation in to MNF, using a socio-ecological systems approach to characterise MNF, assessing its relevance to Sustainable Development Goals. I first review relevant assumptions of negative social and ecological impacts of MNF; discussing potential for positive impacts in terms of food and nutrition security, livelihoods and social equity. I present a conceptual framework which is then utilised to direct policy analysis across relevant sectors in a workshop setting through expert knowledge elicitation. Potential strategies to address MNF across health, development and fisheries governance structures are presented. I also conduct the first global assessment of the prevalence and characteristics of MNF, highlighting its widespread nature. Using a case study in Cabo Delgado, Mozambique I test both entrenched and emerging theories on the drivers and impacts of MNF in a coral reef fishery. Using a rapid assessment of fish landings I demonstrate the likely impact of MNF on catches of legal gears and biodiversity. MNF is a gendered activity, whereby predominantly androcentric methods show potential for negative impacts but gynocentric methods show limited resource overlap. I then use a household survey to contextualise the food security and livelihoods contributions of MNF. MNF is shown to be an important part of household livelihood profiles and particularly in adaptive strategies beyond subsistence in mixed agriculture and fishing communities. The research legitimises concern over MNF sustainability but highlights recklessness in current management based on broad, unsubstantiated assumptions; particularly ineffective enforcement policies. I demonstrate opportunities for MNF to enhance wellbeing and discuss this in light of relevant paradigm shifts, highlighting the critical need for further investigation.
title: 01_2899
Creators: name: Wesley Baldwin, John
name: Baldwin, John W.
Publisher: name: NAKALA - https://nakala.fr (Huma-Num - CNRS)
publisherIdentifier: https://ror.org/04ces3204
publisherIdentifierScheme: ROR
Year: 2018
Subjects: subject: LaMOP
subject: Laboratoire de Médiévistique Occidentale de Paris

description: L'ensemble de ces notes ont été crée par John Baldwin lors d'une de ses premières périodes de résidence à Paris. Ces documents comprennent tous les magistri qu’il avait pu rencontrer dans ses sources. Aux XIIème et XIIIème siècles, les universités n'existant pas encore, le titre de magister s'il évoque certainement une compétence n'est pas rattaché de façon systématique au passage par les écoles. De surcroît, les magistris sont le plus souvent désignés par leur seul prénom. La lecture de ces données est donc difficile et suppose un long travail pour tenter d'identifier un individu auquel on pourrait rattacher plusieurs mentions. John Baldwin avait donc renoncé à utiliser ces données pour donner un prolongement à sa magnifique étude sur les gradués d'université et leur emploi par les Capétiens et les Plantagenêts. Néanmoins, il a conservé ces données et elles sont potentiellement très utile dans le cadre de Studium, comme le sont toutes les mentions dans les volumes des Fasti Ecclesiae Gallicanae de chanoines portant ce titre de magister sans autres précisions. L'ampleur des dépouillements rend ces données très utiles et nous devons une grande reconnaissance à John Baldwin pour avoir pris la peine de faire photocopier ses fiches et de nous les avoir transmises amicalement.
Les données ainsi que les images des fiches sont accessibles sur le site Internet à l'adresse suivante : http://studium-baldwin.lamop.fr/.
Les transcriptions des fiches ont été effectuées par des étudiants de Paris 1 Panthéon - Sorbonne mais elles n'ont pas été corrigées par la suite.
description: Relation: https://lamop.hypotheses.org/
COMET Phase-I Track Reconstruction using Machine Learning and Computer Vision
Creators: name: Gillies, Ewen
Publisher: name: Imperial College London
Year: 2018

description: The COMET experiment will measure Charged Lepton Flavour Violation by searching for the neutrinoless decay of a muon into an electron while the muon is electromagnetically bound to an atomic nucleus. This μ-e conversion process is not allowed in the Standard Model of particle physics which makes it an excellent probe for Beyond the Standard Model physics. The first phase of the experiment will improve the current sensitivity limit on μ-e conversion from the 7.0 × 10−13 at 90% C.L. to 3.0 × 10−15 at 90% C.L. To achieve this, COMET will utilize several novel design elements to produce the world’s high-intensity muon beam to maximise the number of observed muonic atoms. The high-intensity design of this experiment poses significant challenges to both the tracking and triggering systems. A novel algorithm called the CDC Hit Filter is designed to alleviate these challenges. The algorithm utilizes machine learning classification and a circular Hough Transform to identify and remove background hits. When applied offline, it can remove 98% of background hits while retaining 98% of signal hits. When adapted to the online environment, it can remove 89% of the background hits considered by the trigger while retaining 89% of signal hits. Both of these mark a significant improvement over the more traditional cut-based approach, which can remove 75% of background hits while retaining 75% of signal hits.
forfigshare-KhashemAlmogor.ply
Creators: name: Brassey, Charlotte
Publisher: name: figshare
Year: 2018
Subjects: subject: 210105 Archaeology of Europe, the Mediterranean and the Levant
subject: FOS: History and archaeology

description: Rock art panel from Wadi Rum, Jordan. Hunting scene.
Panel 9 Khashem Almogor (ACOR Wadi Rum rock art database)
title: ADCO, Cartulaire général de Cîteaux, dit de Jean de Cirey, (XVe siècle), tome IV, Cart. 188 (11 H 73), f. 0220v
Creators: name: de la Côte d'Or, Archives départementales
name: Archives Départementales De La Côte-D'Or
name: Petot, Frédérique
name: Projet CBMA
name: CG21/F.PETOT/2012
Publisher: name: NAKALA - https://nakala.fr (Huma-Num - CNRS)
publisherIdentifier: https://ror.org/04ces3204
publisherIdentifierScheme: ROR
Year: 2020
Subjects: subject: cartulaire
subject: LaMOP
subject: Laboratoire de Médiévistique Occidentale de Paris
subject: Corpus Burgundiae Medii Aevi
subject: Chartes de la Bourgogne du Moyen Âge

description: Cartulaire général de Cîteaux, dit de Jean de Cirey, (XVe siècle), tome IV, Archives départementales de la Côte-d'Or, Cart. 188 (11 H 73), f. 0220v, Numérisation en mode image.
description: Relation: http://www.cbma-project.eu/
description: Bibliographic citation: Cartulaire général de Cîteaux, dit de Jean de Cirey, (XVe siècle), tome IV, Archives départementales de la Côte-d'Or, Cart. 188 (11 H 73), f. 0220v, in Projet CBMA - Corpus Burgundiae Medii Aevi [Ressource en ligne], https:// manuscrits.cbma-project.eu/
description: Provenance: https://www.geonames.org/3024876
description: Provenance: http://www.idref.fr/030974844/id
description: Provenance: https://catalogue.bnf.fr/ark:/12148/cb12228351v
description: Provenance: abbaye de Cîteaux
description: Provenance: http://www.wikidata.org/entity/Q843261