cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Electron energy-loss spectroscopy on freestanding perforated gold films
Creators: name: Prämassing, M.
name: Kiel, T.
name: Irsen, S.
name: Busch, K.
name: Linden, S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We report on a combined far- and near-field study of surface plasmon polaritons on freestanding perforated gold films. The samples are fabricated by focused ion beam milling of {a periodic hole array into} a carbon membrane followed by thermal evaporation of gold and plasma ashing of the carbon film. Optical transmission spectra show a series of characteristic features, which can be attributed to the excitation of surface plasmon modes via the periodic nanohole array. The corresponding near-field distributions are mapped by electron energy-loss spectroscopy. Besides the optically bright surface plasmon modes, we observe in the near-field an additional dark plasmon mode, which is absent in the normal incidence far-field spectra. Our experimental results are in good agreement with numerical computations based on a discontinuous Galerkin time-domain method.
The thermal nature of high p_T photons in high energy nuclear collisions
Creators: name: Gale, Charles
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We discuss the recent status of some penetrating electromagnetic probes of relativistic nuclear collisions, and the information contained in their measurement. We concentrate in turn on sources that produce high p_T photons: those of purely thermal origin, those producing direct photons, those related to jet fragmentation, and those associated with the interaction of jets with the colored plasma. Whenever possible, we compare with RHIC data and in some cases we make predictions for the LHC.
description: 8 pages
QCD at Zero Baryon Density and the Polyakov Loop Paradox
Creators: name: Kratochvila, S.
name: de Forcrand, Ph.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We compare the grand canonical partition function at fixed chemical potential mu with the canonical partition function at fixed baryon number B, formally and by numerical simulations at mu=0 and B=0 with four flavours of staggered quarks. We verify that the free energy densities are equal in the thermodynamic limit, and show that they can be well described by the hadron resonance gas at T < T_c and by the free fermion gas at T>T_c. Small differences between the two ensembles, for thermodynamic observables characterising the deconfinement phase transition, vanish with increasing lattice size. These differences are solely caused by contributions of non-zero baryon density sectors, which are exponentially suppressed with increasing volume. The Polyakov loop shows a different behaviour: for all temperatures and volumes, its expectation value is exactly zero in the canonical formulation, whereas it is always non-zero in the commonly used grand-canonical formulation. We clarify this paradoxical difference, and show that the non-vanishing Polyakov loop expectation value is due to contributions of non-zero triality states, which are not physical, because they give zero contribution to the partition function.
description: 21 pages, 7 figures
A Comprehensive Analysis on the Pion-Photon Transition Form Factor Beyond the Leading Fock State
Creators: name: Huang, Tao
name: Wu, Xing-Gang
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We perform a comprehensive analysis of the pion-photon transition form factor $F_{πγ}(Q^2)$ involving the transverse momentum corrections with the present CLEO experimental data, in which the contributions beyond the leading Fock state have been taken into consideration. As is well-known, the leading Fock-state contribution dominates of $F_{πγ}(Q^2)$ at large momentum transfer ($Q^2$) region. One should include the contributions beyond the leading Fock state in small $Q^2$ region. In this paper, we construct a phenomenological expression to estimate the contributions beyond the leading Fock state based on its asymptotic behavior at $Q^2\to0$. Our present theoretical results agree well with the experimental data in the whole $Q^2$ region. Then, we extract some useful information of the pionic leading twist-2 distribution amplitude (DA) by comparing our results of $F_{πγ}(Q^2)$ with the CLEO data. By taking best fit, we have the DA moments, $a_2(μ_0^2)=0.002^{+0.063}_{-0.054}$, $a_4(μ_0^2)=-0.022_{-0.012}^{+0.026}$ and all of higher moments, which are closed to the asymptotic-like behavior of the pion wavefunction.
description: 25 pages, 7 figures. Typo error corrected
Dilatation operator or Hamiltonian?
Creators: name: Sochichiu, Corneliu
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We analyze the situation when the Hamiltonian in field theory can be replaced by the dilatation operator.
description: 5 pages, contribution to Constituents, Fundamental Forces And Symmetries Of The Universe
Uncertainty Estimation in Medical Image Localization: Towards Robust Anterior Thalamus Targeting for Deep Brain Stimulation
Creators: name: Liu, Han
name: Cui, Can
name: Englot, Dario J.
name: Dawant, Benoit M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Atlas-based methods are the standard approaches for automatic targeting of the Anterior Nucleus of the Thalamus (ANT) for Deep Brain Stimulation (DBS), but these are known to lack robustness when anatomic differences between atlases and subjects are large. To improve the localization robustness, we propose a novel two-stage deep learning (DL) framework, where the first stage identifies and crops the thalamus regions from the whole brain MRI and the second stage performs per-voxel regression on the cropped volume to localize the targets at the finest resolution scale. To address the issue of data scarcity, we train the models with the pseudo labels which are created based on the available labeled data using multi-atlas registration. To assess the performance of the proposed framework, we validate two sampling-based uncertainty estimation techniques namely Monte Carlo Dropout (MCDO) and Test-Time Augmentation (TTA) on the second-stage localization network. Moreover, we propose a novel uncertainty estimation metric called maximum activation dispersion (MAD) to estimate the image-wise uncertainty for localization tasks. Our results show that the proposed method achieved more robust localization performance than the traditional multi-atlas method and TTA could further improve the robustness. Moreover, the epistemic and hybrid uncertainty estimated by MAD could be used to detect the unreliable localizations and the magnitude of the uncertainty estimated by MAD could reflect the degree of unreliability for the rejected predictions.
description: 8 pages, 3 figures
Διασύνδεση διαδοχικών σταδίων μετατροπέων μήκους κύματος σε ρυθμούς μετάδοσης 10Gb/s: Συγκριτική μελέτη αρχιτεκτονικών SOA-MZI τεχνολογίας:
Creators: name: Αλεξούδη, Θεονίτσα Γεώργιου
name: Παπαϊωάννου, Σωτήριος Δημητρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2010
Subjects: Μετατροπή Μήκους Κύματος
Ημιαγώγιμοι Οπτικοί Ενισχυτές
Συμβολόμετρα Mach – Zehnder
Wavelength Conversion
Semiconductor Optical Amplifiers
Mach – Zehnder Interferometers

description: Στην παρούσα διπλωματική εργασία παρουσιάζονται τρεις αρχιτεκτονικές αμιγώς οπτικής μετατροπής μήκους κύματος. Η μετατροπή μήκους κύματος αποτελεί τον τρόπο με τον οποίο επιτυγχάνεται οπτική μεταγωγή και εντάσσεται στην προσπάθεια υλοποίησης διαφανών οπτικών δικτύων. Κάθε μία από τις αρχιτεκτονικές επιτυγχάνει με τη χρήση της SOA-MZI τεχνολογίας μετατροπή μήκους κύματος NRZ παλμών στα 10Gb/s. Η πρώτη αρχιτεκτονική, Standard Scheme – Single CTR, χρησιμοποιεί ένα συνεχές σήμα εισόδου και ένα σήμα ελέγχου σε διαφορετικό μήκος κύματος. Η δεύτερη αρχιτεκτονική, Bidirectional Input Scheme, χρησιμοποιεί και ένα δεύτερο σήμα ελέγχου, διαδιδόμενο σε αντίθετη κατεύθυνση σε σχέση με το πρώτο αλλά στο ίδιο μήκος κύματος με αυτό. Η τρίτη αρχιτεκτονική, Differentially Biased Bidirectional Scheme, εισάγει στη δεύτερη αρχιτεκτονική ένα επιπλέον συνεχές σήμα εισόδου σε ένα τρίτο μήκος κύματος. Στην εργασία αυτή μελετάται η συμπεριφορά των αρχιτεκτονικών αυτών σε διασύνδεση διαδοχικών σταδίων. Η διασύνδεση διαδοχικών μετατροπέων μήκους κύματος πραγματοποιείται με τη χρήση οπτικών ινών που καλύπτουν χιλιομετρικές αποστάσεις. Έπειτα από μία διαδικασία πολλαπλών προσομοιώσεων αναλύονται οι δυνατότητες και οι αδυναμίες κάθε μίας από τις αρχιτεκτονικές και παρουσιάζονται τα τελικά συγκριτικά αποτελέσματα. Η παραπάνω διαδικασία οδήγησε στο συμπέρασμα ότι η αρχιτεκτονική του Differentially Biased Bidirectional Scheme επιτυγχάνει την καλύτερη απόδοση σε σχέση με τις άλλες δύο αρχιτεκτονικές.
description: In this diploma thesis, three schemes for all-optical wavelength conversion (WC) are presented. Optical switching intending to transparent networks is achieved by using wavelength conversion. Each of the three WC schemes performs SOA-MZI based wavelength conversion of NRZ pulses at 10Gb/s. The first scheme, Standard Scheme – Single CTR, uses a continuous wave (CW) input signal and a control signal (CTR) at different wavelength. The second scheme, Bidirectional Input Scheme, uses a second counter-propagating CTR at the same wavelength with the first CTR signal. The last scheme, Differentially Biased Bidirectional Scheme, includes also an external CW input signal at a different wavelength from the others above. In this project, we present the results of each scheme in successive cascades. The successive cascades of each scheme are connected with fiber transmission systems. Simulations have shown the prospects and the weaknesses of each scheme at the final comparative results. Conclusively, the Differentially Biased Bidirectional Scheme performs better than the other schemes.
The C-metric as a colliding plane wave space-time
Creators: name: Griffiths, J. B.
name: Halburd, R. G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: It is explicitly shown that part of the C-metric space-time inside the black hole horizon may be interpreted as the interaction region of two colliding plane waves with aligned linear polarization, provided the rotational coordinate is replaced by a linear one. This is a one-parameter generalization of the degenerate Ferrari-Ibanez solution in which the focussing singularity is a Cauchy horizon rather than a curvature singularity.
description: 6 pages. To appear in Classical and Quantum Gravity
Pseudo-unitarizable weight modules over generalized Weyl algebras
Creators: name: Hartwig, Jonas T.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Rings and Algebras (math.RA)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: 16D80, 16S36

description: We define a notion of pseudo-unitarizability for weight modules over a generalized Weyl algebra (of rank one, with commutative coeffiecient ring $R$), which is assumed to carry an involution of the form $X^*=Y$, $R^*\subseteq R$. We prove that a weight module $V$ is pseudo-unitarizable iff it is isomorphic to its finitistic dual $V^\sharp$. Using the classification of weight modules by Drozd, Guzner and Ovsienko, we obtain necessary and sufficient conditions for an indecomposable weight module to be isomorphic to its finitistic dual, and thus to be pseudo-unitarizable. Some examples are given, including $U_q(\mathfrak{sl}_2)$ for $q$ a root of unity.
description: 38 pages
Cost-effectiveness on sanitary interventions to improve Dibiteries safety in Dakar, Senegal
Creators: name: Orou Seko, M.
name: A.P.N. Ndour
name: W. Ossebi
name: K. Kreppel
name: J. Saric
name: D. Dao
name: B. Bonfoh
Publisher: name: AAS Open Research
Year: 2019

description: Objectives: In Senegal, the phenomenon of street food is growing with informal restaurant called ‘dibiteries’ offering braised meat to consumers. The aim is to design a low cost and beneficial hygiene intervention for the dibiteries business.
Methods: Thirty random samples of braised meat were taken one month before the trial (step 1), one month (step 2) and one year after the trial (step 3). The trial consisted of three groups: group 1 (control) received no intervention, group 2 received only well-defined equipment and consumables and group 3 received a
standardised training module as well as hygiene package. All samples taken were analysed in laboratory.
Results: Overall, the microbial quality of the braised meat samples improved along the intervention steps. Moreover, the same downward trend is observed at groups level, regardless of the step considered. However, Groups 2 and 3 did not significantly improve the microbial quality. The cost of hygiene improvement and cost of intervention were low ($0.07/day/dibiterie and $0.010/day).
Conclusion: Despite the perceived low cost of intervention, the innovations promoted had a low effectiveness on improving the quality of meat. The adoption of an intervention package is linked to institutional arrangement that provides sustainable conditions for investments. Other adoption factors linked to behaviour need further investigation.
Matrix meets Data Fellows – Learning Objectives as a Starting Point for the Development of Trainings for (Future) Data Stewards
Creators: name: Petersen, Britta
Publisher: name: Zenodo
Year: 2025
Subjects: Learning objective
Data Steward
Training
Research Data Management
RDM

description: Matrix meets Data Fellows – Learning Objectives as a Starting Point for the Development of Trainings for (Future) Data Stewards was presented during Fellowship of the Data 2025 in Jena.

The presentations points out to the matrix of learning objectives for research data management (https://doi.org/10.5281/zenodo.7034477) as a structured framework to support the design and evaluation of training initiatives in the field of RDM. Given the evolving nature of the Data Steward role and the increasing demand for tailored, skill-based trainings in handling research data, the matrix offers an adaptable tool for training developers and institutions. This presentation introduces the matrix as a community product and discusses its potential use in practice-oriented education and professional development.

A LiaScript rendered version of this presentation is available here.
Critical points of the Black-Hole potential for homogeneous special geometries
Creators: name: D'Auria, R.
name: Ferrara, S.
name: Trigiante, M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We extend the analysis of N=2 extremal Black-Hole attractor equations to the case of special geometries based on homogeneous coset spaces. For non-BPS critical points (with non vanishing central charge) the (Bekenstein-Hawking) entropy formula is the same as for symmetric spaces, namely four times the square of the central charge evaluated at the critical point. For non homogeneous geometries the deviation from this formula is given in terms of geometrical data of special geometry in presence of a background symplectic charge vector.
description: 17 pages, LaTeX file
SPECULOOS -- Ultracool Dwarf Transit Survey: Target List and Strategy
Creators: name: Sebastian, D.
name: Gillon, M.
name: Ducrot, E.
name: Pozuelos, F. J.
name: Garcia, L. J.
name: Günther, M. N.
name: Delrez, L.
name: Queloz, D.
name: Demory, B. O.
name: Triaud, A. H. M. J.
name: Burgasser, A.
name: de Wit, J.
name: Burdanov, A.
name: Dransfield, G.
name: Jehin, E.
name: McCormac, J.
name: Murray, C. A.
name: Niraula, P.
name: Pedersen, P. P.
name: Rackham, B. V.
name: Sohy, S.
name: Thompson, S.
name: Van Grootel, V.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: One of the most promising avenues for the detailed study of temperate Earth-sized exoplanets is the detection of such planets in transit in front of stars small and nearby enough to make possible their thorough atmospheric characterisation with next generation telescopes like the James Webb Space telescope (JWST) or Extremely Large Telescope (ELT). In this context, the TRAPPIST-1 planets form an unique benchmark system that has gathered the interest of a large scientific community. The SPECULOOS survey is an exoplanet transit survey, that targets a volume-limited (40 pc) sample of ultracool dwarf stars. We define the SPECULOOS target list as the sum of three non-overlapping sub-programs incorporating the latest type objects (T_eff < 3000K): Program1: 365 dwarfs that are small and nearby enough to make possible the detailed atmospheric characterisation of an `Earth-like' planet with the upcoming JWST, Program2: 171 dwarfs of M5-type and later for which a significant detection of a planet similar to TRAPPIST-1b should be within reach of the exoplanet transit survey TESS, and Program3: 1121 dwarfs later than M6-type that aims to perform a statistical census of short-period planets around ultracool dwarf stars. Our compound target list includes 1657 photometrically classified late-type dwarfs. 260 of these targets are classified for the first time as possible nearby ultracool dwarf stars. Our general observational strategy is to monitor each target for 100 to 200hr with our telescope network, by efficiently using the synergy with TESS for our Program2 and a fraction of the targets of Program1. We expect to detect up to a few dozens temperate, rocky planets, a handful of them being amenable for atmospheric characterisation with JWST and other future giant telescopes which will improve drastically our understanding of the planetary population of the latest-type stars.
description: Accepted for publication in A&A, 13pages, 10 figures
Walking together without collaborating: exploring practices of veterinary and medical health workers regarding brucellosis in northern Cote d’Ivoire.
Creators: name: Y.S.A Babo
name: G. Fokou
name: R.B. Yapi
name: B.V.  Kone
name: W.  Oyetola
name: K. Dayoro
name: R. Kazwala
name: B. Bonfoh
Publisher: name: AAS Open Research
Year: 2019

description: OBJECTIVE: This study aimed to explore cognitive factors for sectoral brucellosis approach control in human and animal health in northern Côte d’Ivoire.
METHOD: The survey was conducted in northern Cote d’Ivoire, an area with dominated by pastoralists. Five administrative regions were involved: Hambol, Poro, Bagoué, Kabadougou and Tchologo. Data were collected using a qualitative approach. Semi-structured interviews were conducted with fourteen (14) veterinarians, and twelve (12) public health workers. Topics discussed centred around their knowledge of brucellosis, strategies for its control, and collaborations and synergies of brucellosis control between the human and animal health sector.
RESULTS: Findings from the study show, that 1) different sources and levels of knowledge on brucellosis exist, based on various experiences and symptomatology. 2) these different levels of knowledge are the basis for the lack of integrated interventions of human and animal health service providers for brucellosis control. Integrated control strategies linking health workers and veterinarians for zoonotic diseases such as brucellosis are still
limited. Exceptions are rabies and Ebola control.
CONCLUSION: Initiatives integrating human and animal health provision are prerequisite for the success of
brucellosis control strategies through the promotion of intersectoral partnerships and homogenization of
brucellosis knowledge among stakeholders
Large-Scale Radio and X-ray Jets in the Highest Redshift Quasars
Creators: name: Cheung, C. C.
name: Wardle, J. F. C.
name: Lee, N. P.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We describe our program to search for and study the kilo-parsec scale radio jets in a sample of high-redshift (greater than 3.4), flat spectrum quasars using new and archival VLA data. Two of these radio jets have been imaged with Chandra, and have X-ray counterparts and are briefly discussed. These high-redshift sources are important targets for testing current X-ray jet emission models for kpc-scale jets and follow-up multi-wavelength observations will shed light on this problem.
description: 6 pages, 3 figures
A Comparison Between the Globular Clusters in NGC 5128 and the Galaxy
Creators: name: Bergh, Sidney van den
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Some of the properties of the globular clusters in NGC 5128 are compared to those of Galactic globular clusters. Assuming the color- metallicity relations that hold for Galactic globular clusters then the metal-poor clusters in NGC 5128 that have [Fe/H] < -1.80 are significantly fainter than are the more metal-rich globulars in that galaxy. No such metallicity dependent luminosity difference is observed among the globular clusters associated with the Milky Way. Furthermore the NGC 5128 cluster sample contains two objects that, on the basis of their observed colors, appear to be super metal-poor. It is speculated that many of these apparently faint and metal-poor clusters in NGC 5128 are actually objects resembling intermediate-age Galactic open clusters. It is also found that large clusters with FWHM > 10 pc are typically less luminous in NGC 5128 than are their more more compact counterparts. In this respect the NGC 5128 cluster system is similar to the Galactic globular cluster system. Finally, the present data may hint at the possibility that the NGC 5128 cluster system differs from that surrounding the Milky Way, in that the NGC 5128 objects do not seem to exhibit a clear cut gap between the regions of the FWHM vs M_v plane that are occupied by globular clusters and dwarf spheroidal galaxies.
description: To be published in the Astronomical Journal
Liquidity Stress Testing in Asset Management -- Part 1. Modeling the Liability Liquidity Risk
Creators: name: Roncalli, Thierry
name: Karray-Meziou, Fatma
name: Pan, François
name: Regnault, Margaux
Publisher: name: arXiv
Year: 2021
Subjects: subject: Risk Management (q-fin.RM)
subject: Computational Finance (q-fin.CP)
subject: Applications (stat.AP)
subject: FOS: Economics and business
subject: FOS: Computer and information sciences
subject: G.3
subject: 91B05, 91G70, 62P05,

description: This article is part of a comprehensive research project on liquidity risk in asset management, which can be divided into three dimensions. The first dimension covers liability liquidity risk (or funding liquidity) modeling, the second dimension focuses on asset liquidity risk (or market liquidity) modeling, and the third dimension considers asset-liability liquidity risk management (or asset-liability matching). The purpose of this research is to propose a methodological and practical framework in order to perform liquidity stress testing programs, which comply with regulatory guidelines (ESMA, 2019) and are useful for fund managers. The review of the academic literature and professional research studies shows that there is a lack of standardized and analytical models. The aim of this research project is then to fill the gap with the goal to develop mathematical and statistical approaches, and provide appropriate answers. In this first part that focuses on liability liquidity risk modeling, we propose several statistical models for estimating redemption shocks. The historical approach must be complemented by an analytical approach based on zero-inflated models if we want to understand the true parameters that influence the redemption shocks. Moreover, we must also distinguish aggregate population models and individual-based models if we want to develop behavioral approaches. Once these different statistical models are calibrated, the second big issue is the risk measure to assess normal and stressed redemption shocks. Finally, the last issue is to develop a factor model that can translate stress scenarios on market risk factors into stress scenarios on fund liabilities.
Correlation between optical and $γ$-ray flux variations in bright flat spectrum radio quasars
Creators: name: Rajput, Bhoomika
name: Stalin, C. S.
name: Sahayanathan, S.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Blazars are known to show flux variations over a range of energies from low energy radio to high energy gamma-rays. Cross-correlation analysis of the optical and $γ$-ray light curves in blazars shows that flux variations are generally correlated in both bands, however, there are exceptions. We explored this optical-GeV connection in four flat spectrum radio quasars (FSRQs) by a systematic investigation of their long term optical and $γ$-ray light curves. On analysis of the four sources, namely 3C 273, 3C 279, PKS 1510$-$089 and CTA 102 we noticed different behaviours between the optical and GeV flux variations. We found instances when (i) the optical and GeV flux variations are closely correlated (ii) there are optical flares without $γ$-ray counterparts and (iii) $γ$-ray flares without optical counterparts. To understand these diverse behaviours, we carried out broad band spectral energy distribution (SED) modelling of the sources at different epochs using a one-zone leptonic emission model. The optical-UV emission is found to be dominated by emission from the accretion disk in the sources PKS 1510$-$089, CTA 102 and 3C 273, while in 3C 279, the synchrotron radiation from the jet dominates the optical-UV emission. Our SED analysis indicates that (i) correlated optical and $γ$-ray flux variations are caused by changes in the bulk Lorentz factor ($Γ$), (ii) $γ$-ray flares without optical counterparts are due to increase in $Γ$ and/or the electron energy density and (iii) an optical flare without $γ$-ray counterpart is due to increase in the magnetic field strength.
description: 22 pages, 32 figures, accepted to MNRAS
Scattering of Glue by Glue on the Light-cone Worldsheet II: Helicity Conserving Amplitudes
Creators: name: Chakrabarti, D.
name: Qiu, J.
name: Thorn, C. B.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: This is the second of a pair of articles on scattering of glue by glue, in which we give the light-cone gauge calculation of the one-loop on-shell helicity conserving scattering amplitudes for gluon-gluon scattering (neglecting quark loops). The 1/p^+ factors in the gluon propagator are regulated by replacing p^+ integrals with discretized sums omitting the p^+=0 terms in each sum. We also employ a novel ultraviolet regulator that is convenient for the light-cone worldsheet description of planar Feynman diagrams. The helicity conserving scattering amplitudes are divergent in the infra-red. The infrared divergences in the elastic one-loop amplitude are shown to cancel, in their contribution to cross sections, against ones in the cross section for unseen bremsstrahlung gluons. We include here the explicit calculation of the latter, because it assumes an unfamiliar form due to the peculiar way discretization of p^+ regulates infrared divergences. In resolving the infrared divergences we employ a covariant definition of jets, which allows a transparent demonstration of the Lorentz invariance of our final results. Because we use an explicit cutoff of the ultraviolet divergences in exactly 4 space-time dimensions, we must introduce explicit counterterms to achieve this final covariant result. These counter-terms are polynomials in the external momenta of the precise order dictated by power-counting. We discuss the modifications they entail for the light-cone worldsheet action that reproduces the ``bare'' planar diagrams of the gluonic sector of QCD. The simplest way to do this is to interpret the QCD string as moving in six space-time dimensions.
description: 56 pages, 21 figures, references added, minor typos corrected
Thermodynamical limit of general gl(N) spin chains: vacuum state and densities
Creators: name: Crampe, N.
name: Frappat, L.
name: Ragoucy, E.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We study the vacuum state of spin chains where each site carry an arbitrary representation. We prove that the string hypothesis, usually used to solve the Bethe ansatz equations, is valid for representations characterized by rectangular Young tableaux. In these cases, we obtain the density of the center of the strings for the vacuum. We work out different examples and, in particular, the spin chains with periodic array of impurities.
description: Latex file, 27 pages, 5 figures (.eps) A more detailed study of the representations allowing string hypothesis has added. A simpler formula for the densities is given. References added and misprint corrected
Dynamics of the Nearly Parametric Pendulum
Creators: name: Horton, B.
name: Sieber, J.
name: Thompson, J. M. T.
name: Wiercigroch, M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 37G15

description: Dynamically stable periodic rotations of a driven pendulum provide a unique mechanism for generating a uniform rotation from bounded excitations. This paper studies the effects of a small ellipticity of the driving, perturbing the classical parametric pendulum. The first finding is that the region in the parameter plane of amplitude and frequency of excitation where rotations are possible increases with the ellipticity. Second, the resonance tongues, which are the most characteristic feature of the classical bifurcation scenario of a parametrically driven pendulum, merge into a single region of instability.
description: 7 pages, 5 figures
Effects of Mass Media and Cultural Drift in a Model for Social Influence
Creators: name: Mazzitello, Karina I.
name: Candia, Julián
name: Dossetti, Víctor
Publisher: name: arXiv
Year: 2006
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: In the context of an extension of Axelrod's model for social influence, we study the interplay and competition between the cultural drift, represented as random perturbations, and mass media, introduced by means of an external homogeneous field. Unlike previous studies [J. C. González-Avella {\it et al}, Phys. Rev. E {\bf 72}, 065102(R) (2005)], the mass media coupling proposed here is capable of affecting the cultural traits of any individual in the society, including those who do not share any features with the external message. A noise-driven transition is found: for large noise rates, both the ordered (culturally polarized) phase and the disordered (culturally fragmented) phase are observed, while, for lower noise rates, the ordered phase prevails. In the former case, the external field is found to induce cultural ordering, a behavior opposite to that reported in previous studies using a different prescription for the mass media interaction. We compare the predictions of this model to statistical data measuring the impact of a mass media vasectomy promotion campaign in Brazil.
description: 10 pages, 3 figures; minor changes; added references. To appear in IJMPC
title: Ultrahochdruck-Eklogite aus dem nordwestlichen Himalaya: eine Studie zu den
Druck-Temperatur-Zeit-Bedingungen ihrer Exhumation
Creators: name: Wilke, Franziska
Publisher: name: Deutsches GeoForschungsZentrum GFZ
Year: 2013

description: Using petrology, isotope geochemistry and thermochronology, continental rocks were investigated that have been subducted and metamorphosed under ultra high-pressure (UHP) conditions. The metamorphic conditions during burial and exhumation of eclogites, schists and gneisses from the tectonically and climatically influenced north-western Himalaya, from the Kaghan Valley in Pakistan, were analysed, and ages and rates of exhumation determined. A multi-stage exhumation path is evident. It is shown that the UHP rocks initially experienced very rapid exhumation of up to 14 cm/a from mantle depths (~140 km) to the base of the continental crust (~40 km) where exhumation slows down to 1 to 2 mm/a. The initial exhumation is buoyancy driven and as fast as recent plate movements (ca. 10 cm/a). Changes in the exhumation rate point to changes in buoyancy and to particular processes forcing further exhumation and final exposure such as thrusting, folding and back sliding. Similar processes have been recognized at Tso Morari, Ladakh, NW India where comparable rock assemblages occur and where research is in progress.
description: System Erde; 3
The role of Epstein-Barr virus in the pathogenesis of lymphocytic interstitial pneumonia
Creators: name: Kaan, Philomena M.
Publisher: name: University of British Columbia
Year: 2009

description: Epstein-Barr Virus (EBV) genome has been demonstrated in lung tissues of patients with lymphocytic interstitial pneumonia (LIP). Recent in vitro studies have shown that the EBV immortalizes and transforms cells by upregulation of the cellular proto-oncogene bcl-2 via the viral latent membrane protein LMP1. The purpose of the studies described in this thesis was to determine whether the presence of EBV LMP1 and over-expression of bcl-2 occurs in LIP. Immunohistochemistry was employed to detect EBV LMP1 and bcl-2 in formalin-fixed, paraffin-embedded lung sections from patients with LIP (n = 14), idiopathic pulmonary fibrosis (IPF, n = 9) and autopsy cases (AC, n = 9) without lung disease. EBV density, defined by the number of LMP1 positive cells per unit area of lung tissue, was used to estimate the level of LMP1 expression. The results showed increased LMP1 expression in lung tissue from patients with LIP (p<0.05). bcl-2 expression was assessed by a grading system based on cellularity (Grade 1, 2 and 3) and intensity of immunostaining (Grade 0, 1, 2, and 3). bcl-2 staining was greatest in LIP (p<0.05), and IPF showed more staining than AC (p<0.05). We conclude that EBV is more prevalent and LMP1 expression was increased in LIP associated with an upregulated bcl-2 expression. These results support the hypothesis that EBV infection is important in the pathogenesis of LIP and bcl-2 may play a role towards lymphomagenesis of LIP.
V605 Aql: The Older Twin of Sakurai's Object
Creators: name: Clayton, Geoffrey C.
name: Kerber, F.
name: Pirzkal, N.
name: De Marco, O.
name: Crowther, P. A.
name: Fedrow, J. M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: New optical spectra have been obtained with VLT/FORS2 of the final helium shell flash (FF) star, V605 Aql, which peaked in brightness in 1919. New models suggest that this star is experiencing a very late thermal pulse. The evolution to a cool luminous giant and then back to a compact hot star takes place in only a few years. V605 Aql, the central star of the Planetary Nebula (PN), A58, has evolved from T$_{eff}\sim$5000 K in 1921 to $\sim$95,000 K today. There are indications that the new FF star, Sakurai's Object (V4334 Sgr), which appeared in 1996, is evolving along a similar path. The abundances of Sakurai's Object today and V605 Aql 80 years ago mimic the hydrogen deficient R Coronae Borealis (RCB) stars with 98% He and 1% C. The new spectra show that V605 Aql has stellar abundances similar to those seen in Wolf-Rayet [WC] central stars of PNe with ~55% He, and ~40% C. The stellar spectrum of V605 Aql can be seen even though the star is not directly detected. Therefore, we may be seeing the spectrum in light scattered around the edge of a thick torus of dust seen edge-on. In the present state of evolution of V605 Aql, we may be seeing the not too distant future of Sakurai's Object.
description: 12 pages, 1 figure, ApJ Letters in press
Watermarking Using Decimal Sequences
Creators: name: Mandhani, Navneet
name: Kak, Subhash
Publisher: name: arXiv
Year: 2006
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: This paper introduces the use of decimal sequences in a code division multiple access (CDMA) based watermarking system to hide information for authentication in black and white images. Matlab version 6.5 was used to implement the algorithms discussed in this paper. The advantage of using d-sequences over PN sequences is that one can choose from a variety of prime numbers which provides a more flexible system.
description: 8 pages, 9 figures
title: Μέτρηση ποιότητας υπηρεσιών ηλεκτρονικής διακυβέρνησης
titleType: AlternativeTitle
title: Evaluation of e-Government service quality
titleType: AlternativeTitle
Creators: name: Papadomichelaki, Xeni G.
Publisher: name: National Technological University of Athens
Year: 2011
Subjects: Αξιολόγηση Ποιότητας
Εργαλεία Μέτρησης Ποιότητας
Ηλεκτρονική Υπηρεσία
Μοντέλο Ποιότητας
Ηλεκτρονική Διακυβέρνηση
Quality Evaluation
Instruments of Quality Evaluation
e-Service
e-Government
Quality Model

description: 280 σ.
description: Η διδακτορική διατριβή τοποθετείται στον ευρύτερο επιστημονικό χώρο της ποιότητας ηλεκτρονικών υπηρεσιών (quality of e-services) και συγκεκριμένα επικεντρώνεται στη μελέτη της μέτρησης της ποιότητας υπηρεσιών που παρέχονται από σελίδες ηλεκτρονικής διακυβέρνησης (assessment of quality of e-government services). Δεδομένων των προβλημάτων των υπαρχόντων μεθόδων μέτρησης, προκύπτει η ανάγκη επιστημονικού προσδιορισμού των κριτηρίων αξιολόγησης της ποιότητας και της σημαντικότητας τους, αλλά και της δυνατότητας επιλογής μεθόδου αξιολόγησης της ποιότητας. Το μοντέλο ποιότητας που αναπτύχθηκε καθορίζει τους βασικούς άξονες και παράγοντες της ποιότητας ηλεκτρονικών υπηρεσιών και ιστοχώρων, που πρέπει να ληφθούν υπ’ όψιν κατά την μέτρηση της, απαντώντας στο ερώτημα σχετικά με το ‘τι πρέπει να μετρηθεί’. Στην συνέχεια απαντώντας στο ερώτημα σχετικά με το ‘πώς πρέπει να μετρηθεί;’ δημιουργήθηκαν δύο εργαλεία μέτρησης της ποιότητας υπηρεσιών ηλεκτρονικής διακυβέρνησης. Το πρώτο εφαρμόζει τη μέθοδο συμπλήρωσης ερωτηματολογίων, αποτελείται από 4 άξονες και 21 παράγοντες και εφαρμόστηκε στις έξι δημοφιλέστερες ιστοσελίδες ηλεκτρονικής διακυβέρνησης της Ελλάδος ενώ το δεύτερο εφαρμόζει την μέθοδο ευρετικής αξιολόγησης, αποτελείται από 3 άξονες, 15 παράγοντες και 50 δείκτες μέτρησης και εφαρμόστηκε σε 50 ιστοτόπους δημοσίων υπηρεσιών, που ανήκουν σε 5 Ευρωπαϊκές χώρες (Ελλάδα, Μεγάλη Βρετανία, Ιρλανδία, Μάλτα, Φιλανδία).
description: This doctoral thesis focuses on the domain of quality of services in electronic government. Considering the problems of the existing methods for measuring the quality of e-government services there is a need to define scientifically the quality evaluation criteria and their relative importance, as well as to provide organizations and practitioners with alternative and flexible ways to assess the quality of the electronic services they deliver, in order to fit their needs and their resources. The developed quality model determines the dimensions and the attributes that should be evaluated in the assessment of e-government service quality and answers to the question ‘what to assess’. Next, for answering the question ‘how the assessment should be done’ two instruments were developed. The first instrument applies inquiry method, constitutes of 4 dimensions and 21 attributes and was implemented on the six most popular e-government sites of Greece, while the second instrument applies inspection method, constitutes of 3 dimensions, 15 attributes and 50 metrics and was implemented on 50 websites of public authorities, which belong to 5 European countries (Greece, United Kingdom, Ireland, Malta and Finland).
Statistical Reliability of 10 Years of Cyber Security User Studies (Extended Version)
Creators: name: Groß, Thomas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Background. In recent years, cyber security security user studies have been appraised in meta-research, mostly focusing on the completeness of their statistical inferences and the fidelity of their statistical reporting. However, estimates of the field's distribution of statistical power and its publication bias have not received much attention. Aim. In this study, we aim to estimate the effect sizes and their standard errors present as well as the implications on statistical power and publication bias. Method. We built upon a published systematic literature review of $146$ user studies in cyber security (2006--2016). We took into account $431$ statistical inferences including $t$-, $χ^2$-, $r$-, one-way $F$-tests, and $Z$-tests. In addition, we coded the corresponding total sample sizes, group sizes and test families. Given these data, we established the observed effect sizes and evaluated the overall publication bias. We further computed the statistical power vis-{à}-vis of parametrized population thresholds to gain unbiased estimates of the power distribution. Results. We obtained a distribution of effect sizes and their conversion into comparable log odds ratios together with their standard errors. We, further, gained funnel-plot estimates of the publication bias present in the sample as well as insights into the power distribution and its consequences. Conclusions. Through the lenses of power and publication bias, we shed light on the statistical reliability of the studies in the field. The upshot of this introspection is practical recommendations on conducting and evaluating studies to advance the field.
description: Open Science Framework: https://osf.io/bcyte. 31 pages. This is the author's copy. This work was supported by the ERC Starting Grant Confidentiality-Preserving Security Assurance (CASCAde), GA no 716980
Ανακάλυψη γνώσης από Blogs: εφαρμογές στην εξόρυξη ψυχικής διάθεσης
Creators: name: Σπυράτου, Ευαγγελία Σπυρίδων
Publisher: name: Aristotle University of Thessaloniki
Year: 2010
Subjects: εξόρυξη γνώσης από ιστολόγια χρηστών
εξόρυξη ψυχικής διάθεσης από ιστολόγια
μηχανική μάθηση
blog data mining
blog mood mining
machine learning

description: Το θέμα της διατριβής αυτής είναι παρουσίαση των κυριότερων ερευνητικών τάσεων, μεθόδων και εφαρμογών που αφορούν στην ανακάλυψη γνώσης από ιστολόγια χρηστών (blogs), ενώ έμφαση δίνεται στην περιοχή της εξόρυξης ψυχικής διάθεσης με τεχνικές μηχανικής μάθησης. Τα ιστολόγια χρηστών αποτελούν μία πλούσια πηγή πληροφοριών στον παγκόσμιο ιστό, στην οποία εφαρμόζονται τεχνικές για την εξόρυξη πολύτιμης γνώσης. Γνώση μπορεί να αποτελέσει και η ψυχική διάθεση που υποδηλώνει κάθε μήνυμα, η οποία δύναται να αξιοποιηθεί κατά την μελέτη της επίδρασης ενός σημαντικού γεγονότος ή προσώπου στην παγκόσμια κοινότητα. Στο πρώτο τμήμα της εργασίας γίνεται ανασκόπηση της βιβλιογραφίας που σχετίζεται με τη διαδικασία της ανακάλυψης γνώσης από κείμενα και ιστολόγια, όπως επίσης και με την εξόρυξη ψυχικής διάθεσης από τέτοιο υλικό. Στο δεύτερο τμήμα παρουσιάζεται μια σειρά πειραμάτων εκπαίδευσης μοντέλων ταξινόμησης της ψυχικής διάθεσης που υποδηλώνουν μηνύματα που προέρχονται από ιστολόγια. Τα πειράματα αυτά έχουν ως στόχο την αξιολόγηση των κειμενικών χαρακτηριστικών που χρησιμοποιούνται για την αναπαράσταση των μηνυμάτων σε εφαρμογές εξόρυξης ψυχικής διάθεσης. Τα μοντέλα ταξινόμησης δημιουργήθηκαν και αξιολογήθηκαν με το λογισμικό Weka. Στη συνέχεια, παρουσιάζεται η διαδικτυακή εφαρμογή που υλοποιήθηκε στο πλαίσιο της παρούσας εργασίας, η οποία αξιοποιεί τα μοντέλα που αναπτύχθηκαν κατά την πειραματική φάση για την πρόβλεψη της υποδηλούμενης ψυχικής διάθεσης άλλων μηνυμάτων.
description: The subject of this thesis is the presentation of the most significant research trends, methods and applications concerning blog data mining using machine learning techniques. Special attention is paid to the field of mood mining. Blogs constitute a valuable web information resource, thus machine learning techniques are applied to them in order to extract useful knowledge. Mood mining can generate knowledge which can be exploited to determine the effect of an important event or a notable person on the worldwide community. In the first part of this thesis, a survey of the literature which is related to text, blog and mood mining is presented. In the second part, a number of mood classification experiments on blog posts are conducted. These experiments aim at the evaluation of the text representation features that are usually chosen in mood mining applications. The classification models were built and evaluated by Weka software. Afterwards, a web application that utilizes these models is presented. This application was developed to predict the mood of the writer of a blog post based on a selected classification model.
On extropy of past lifetime distribution
Creators: name: Kamari, Osman
name: Buono, Francesco
Publisher: name: arXiv
Year: 2020
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 94A17, 62B10, 62G30

description: Recently Qiu et al. (2017) have introduced residual extropy as measure of uncertainty in residual lifetime distributions analogues to residual entropy (1996). Also, they obtained some properties and applications of that. In this paper, we study the extropy to measure the uncertainty in a past lifetime distribution. This measure of uncertainty is called past extropy. Also it is showed a characterization result about the past extropy of largest order statistics.
On the interactions between a propagating shock wave and evaporating water droplets
Creators: name: Huang, Zhiwei
name: Zhang, Huangwei
Publisher: name: arXiv
Year: 2020
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: One-dimensional numerical simulations based on hybrid Eulerian-Lagrangian approach are performed to investigate the interactions between propagating shock waves and dispersed evaporating water droplets in two-phase gas-droplet flows. Two-way coupling for interphase exchanges of mass, momentum and energy is adopted. Parametric study on shock attenuation, droplet evaporation, motion and heating is conducted, through considering various initial droplet diameters (5-20 μm), number densities (2.5 x 1011 - 2 x 1012 1/m3) and incident shock Mach numbers (1.17-1.9). It is found that the leading shock may be attenuated to sonic wave and even subsonic wave when droplet volume fraction is large and/or incident shock Mach number is low. Attenuation in both strength and propagation speed of the leading shock is mainly caused by momentum transfer to the droplets that interact at the shock front. Total pressure recovery is observed in the evaporation region, whereas pressure loss results from shock compression, droplet drag and pressure gradient force behind the shock front. Recompression of the region between the leading shock and two-phase contact surface is observed when the following compression wave is supersonic. After a critical point, this region gets stable in width and interphase exchanges in mass, momentum, and energy. However, the recompression phenomenon is sensitive to droplet volume fraction and may vanish with high droplet loading. For an incident shock Mach number of 1.6, recompression only occurs when the initial droplet volume fraction is below 3.28 x 10-5.