cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Το στοιχείο της βίας στο σύγχρονο αμερικάνικο κινηματογράφο (1992-2007):
Creators: name: Μπαμπατζιμόπουλος, Σωτήριος Χρ.
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Κινηματογράφος
Βία
Αφήγηση
Χόλιγουντ
Cinema
Film
Violence
Narrative

description: O στόχος της παρούσας διατριβής είναι τριπλός: Πρώτον, θα εξεταστεί το στοιχείο της βίας στη σύγχρονη αμερικάνικη κινηματογραφική αφήγηση, καθώς και οι μηχανισμοί με τους οποίους εντάσσεται στην αφήγηση για τη δημιουργία αντίκτυπου στο θεατή. Δεύτερον, θα εξεταστεί η βία σε σχέση με τους χαρακτήρες ως προσδιοριστικός παράγοντας της ταυτότητας και των προθέσεών τους. Τρίτον, θα εξεταστεί η χρήση της βίας ως μέσο σχολιασμού της ίδιας της φύσης της και των μηχανισμών παραγωγής και αναπαραγωγής της. Επιπλέον, θα μελετηθεί κατά πόσο η πρωτοφανής έκρηξη στιλιζαρισμένης βίας, την οποία εγκαινίασε ο Quentin Tarantino και η οποία συνεχίστηκε από σκηνοθέτες όπως οι Oliver Stone και Robert Rodriguez, συνοδεύεται και από μια επαναδιαπραγμάτευση των κωδίκων της βίας ή αντιθέτως οι ήδη υπάρχοντες κώδικες αναπαράγονται με διαφορετικές μεθόδους. Η διατριβή αποτελείται ουσιαστικά από δύο μέρη. Στο πρώτο παρουσιάζεται μια σύντομη ιστορική ανασκόπηση της χρήσης της βίας στον κινηματογράφο από το 1895 μέχρι το 1992, ορίζεται η έννοια της βίας και τίθεται το θεωρητικό πλαίσιο της έρευνας. Στο δεύτερο εξετάζονται ενδελεχώς επτά κινηματογραφικά κείμενα. Πρόκειται για τις ταινίες Unforgiven, Reservoir Dogs, Natural Born Killers, Funny Games, A History of Violence, Sin City και No Country for Old Men.
description: The objective of the present research is threefold: First, to examine the element of violence in contemporary American cinematographic narratives, as well as the mechanisms with which violence is employed in the narration in order to create an effective impact to the viewer. Second, to analyze violence as a defining element of the characters and their identity. Third, to look into violence as a commentary of its cinematographic expression. The dissertation is divided into two parts. In the first part a brief historical overview of the use of violence in cinema from 1895 to 1992 is presented, the notion of violence is defined, and the theoretical background is established. In the second part the following seven films are used as case studies and therefore are thoroughly analyzed: Unforgiven, Reservoir Dogs, Natural Born Killers, Funny Games, A History of Violence and No Country for Old Men.
Small Field Polynomial Inflation: Reheating, Radiative Stability and Lower Bound
Creators: name: Drees, Manuel
name: Xu, Yong
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We revisit the renormalizable polynomial inflection point model of inflation, focusing on the small field scenario which can be treated fully analytically. In particular, the running of the spectral index is predicted to be $α= -1.43 \times 10^{-3} +5.56 \times 10^{-5} \left(N_{\rm CMB}-65 \right)$, which might be tested in future. We also analyze reheating through perturbative inflaton decays to either fermionic or bosonic final states via a trilinear coupling. The lower bound on the reheating temperature from successful Big Bang nucleosynthesis gives lower bounds for these couplings; on the other hand radiative stability of the inflaton potential leads to upper bounds. In combination this leads to a lower bound on the location $ϕ_0$ of the near inflection point, $ϕ_0 > 3 \cdot 10^{-5}$ in Planckian units. The Hubble parameter during inflation can be as low as $H_{\rm inf} \sim 1$ MeV, or as high as $\sim 10^{10}$ GeV. Similarly, the reheating temperature can lie between its lower bound of $\sim 4$ MeV and about $4 \cdot 10^8 \ (10^{11})$ GeV for fermionic (bosonic) inflaton decays. We finally speculate on the "prehistory" of the universe in this scenario, which might have included an epoch of eternal inflation.
description: v2: typos corrected, references updated; expanded discussion on preheating and inflaton scattering; version accepted by JCAP
Works councils and the digitalisation of manufacturing: Opportunity or threat for their power position?
Creators: name: Rego, Kerstin
Publisher: name: Universität Regensburg
Year: 2021
Subjects: subject: Co-determination, digitalisation, power position, power resources, works council
subject: 330 Wirtschaft

description: In the course of the so-called ‘digital transformation’, the digitalisation of manufacturing is on the agenda in many companies. Are works councils, as an important form of workplace representation of employees’ interests, prepared to bring employees’ interests into company digitalisation processes, and does this affect their own position of power? To answer these questions, four in-depth qualitative case studies of works councils from German industrial companies are conducted. The results show that works councils can rely on important resources in the bargaining of digitalisation processes. Through the combination of resource use with other factors, such as the perception of digitalisation and the (un)willingness of management to involve works councils, three different constellations can be identified under which dealing with digitalisation represents an opportunity or a threat for works councils.
A structure-preserving parametric finite element method for surface diffusion
Creators: name: Bao, Weizhu
name: Zhao, Quan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 65M60, 65M12, 35K55, 53C44

description: We propose a structure-preserving parametric finite element method (SP-PFEM) for discretizing the surface diffusion of a closed curve in two dimensions (2D) or surface in three dimensions (3D). Here the "structure-preserving" refers to preserving the two fundamental geometric structures of the surface diffusion flow: (i) the conservation of the area/volume enclosed by the closed curve/surface, and (ii) the decrease of the perimeter/total surface area of the curve/surface. For simplicity of notations, we begin with the surface diffusion of a closed curve in 2D and present a weak (variational) formulation of the governing equation. Then we discretize the variational formulation by using the backward Euler method in time and piecewise linear parametric finite elements in space, with a proper approximation of the unit normal vector by using the information of the curves at the current and next time step. The constructed numerical method is shown to preserve the two geometric structures and also enjoys the good property of asymptotic equal mesh distribution. The proposed SP-PFEM is "weakly" implicit (or almost semi-implicit) and the nonlinear system at each time step can be solved very efficiently and accurately by the Newton's iterative method. The SP-PFEM is then extended to discretize the surface diffusion of a closed surface in 3D. Extensive numerical results, including convergence tests, structure-preserving property and asymptotic equal mesh distribution, are reported to demonstrate the accuracy and efficiency of the proposed SP-PFEM for simulating surface diffusion in 2D and 3D.
description: 26 pages, 14 figures
Semiclassical Quantization of the Giant Magnon
Creators: name: Papathanasiou, Georgios
name: Spradlin, Marcus
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Solitons in field theory provide a window into regimes not directly accessible by the fundamental perturbative degrees of freedom. Motivated by interest in the worldsheet S-matrix of string theory in AdS_5 x S^5 in the limit of infinite worldsheet volume we consider the semiclassical quantization of a particular soliton of this theory: the Hofman-Maldacena `giant magnon' spinning string. We obtain explicit formulas for the complete spectrum of bosonic and fermionic fluctuations around the giant magnon. As an application of these results we confirm that the one-loop correction to the classical energy vanishes as expected.
description: 20 pages, JHEP3 style; v2: minor typos fixed and references added
Surface oscillations in channeled snow flows
Creators: name: Rastello, Marie
name: Bouchet, Alexi
Publisher: name: arXiv
Year: 2007
Subjects: subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: An experimental device has been built to measure velocity profiles and friction laws in channeled snow flows. The measurements show that the velocity depends linearly on the vertical position in the flow and that the friction coefficient is a first-order polynomial in velocity (u) and thickness (h) of the flow. In all flows, oscillations on the surface of the flow were observed throughout the channel and measured at the location of the probes. The experimental results are confronted with a shallow water approach. Using a Saint-Venant modeling, we show that the flow is effectively uniform in the streamwise direction at the measurement location. We show that the surface oscillations produced by the Archimedes's screw at the top of the channel persist throughout the whole length of the channel and are the source of the measured oscillations. This last result provides good validation of the description of such channeled snow flows by a Saint-Venant modeling.
Attitudes towards avatars and in-game behaviours
Creators: name: Foreman, LS
Publisher: name: University of Tasmania
Year: 2024

description: Microtransactions - in-game purchases associated with gambling symptomology, excessive gaming and psychological distress - generate substantial revenue for game publishers. Microtransactions facilitate avatar customisation. However, avatar identification (AID) and avatar customisation are yet to be investigated as individual difference factors relating to in-game spending behaviours. This preregistered, online, quantitative, cross-sectional study surveyed 333 participants (61.3%M, 18 to 64 years) to investigate whether AID moderated a relationship between attitudes towards avatar customisation (ATAC) and in-game spending (outcome variable). We investigated relationships between in-game spending and ATAC; in-game spending and multiplayer gameplay; the Risky Loot Box Index and AID; and ATAC and AID. We found extreme evidence for positive associations between ATAC and loot box and non-randomised spending. No moderation effect was detected, however, we found extreme evidence for a relationship between the RLI and AID, implicating AID with risky loot box behaviours. Extreme evidence for a moderate positive association between AID and ATAC supports previous research findings. Results suggest players who care about avatar customisation are more likely to purchase items that provide direct choice rather than purchases that provide chance-based reward. Findings are examined in relation to Self Determination Theory and implications for future research is discussed.
Time correlation functions for quantum systems: validating Bayesian approaches for harmonic oscillators and beyond
Creators: name: Efremkin, Vladislav
name: Barrat, Jean-Louis
name: Mossa, Stefano
name: Holzmann, Markus
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The quantum harmonic oscillator is the fundamental building block to compute thermal properties of virtually any dielectric crystal at low temperatures in terms of phonons, extended further to cases with anharmonic couplings, or even disordered solids. In general, Path Integral Monte Carlo (PIMC) or Molecular Dynamics (PIMD) methods are powerful tools to determine stochastically thermodynamic quantities without systematic bias, not relying on perturbative schemes. Addressing transport properties, for instance calculating thermal conductivity from PIMC, however, is substantially more difficult. Although correlation functions of current operators can be determined by PIMC from analytic continuation on the imaginary-time axis, Bayesian methods are usually employed for the numerical inversion back to real-time response functions. This task not only strongly relies on the accuracy of the PIMC data, but also introduces noticeable dependence on the model used for the inversion. Here, we address both difficulties with care. In particular, we first devise improved estimators for current correlations which substantially reduce the variance of the PIMC data. Next, we provide a neat statistical approach to the inversion problem, blending into a fresh workflow the classical stochastic maximum entropy method together with recent notions borrowed from statistical learning theory. We test our ideas on a single harmonic oscillator and a collection of oscillators with a continuous distribution of frequencies, and provide indications of the performance of our method in the case of a particle in a double well potential. This work establishes solid grounds for an unbiased, fully quantum mechanical calculation of transport properties in solids.
Neglecting the porosity of hot-star winds can lead to underestimating mass-loss rates
Creators: name: Oskinova, L. M.
name: Hamann, W. -R.
name: Feldmeier, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Context: The mass-loss rate is a key parameter of massive stars. Adequate stellar atmosphere models are required for spectral analyses and mass-loss determinations. Present models can only account for the inhomogeneity of stellar winds in the approximation of small-scale structures that are optically thin. This treatment of ``microclumping'' has led to reducing empirical mass-loss rates by factors of two and more. Aims: Stellar wind clumps can be optically thick in spectral lines. We investigate how this ``macroclumping'' impacts on empirical mass-loss rates. Methods: The Potsdam Wolf-Rayet (PoWR) model atmosphere code is generalized in the ``formal integral'' to account for clumps that are not necessarily optically thin. Results: Optically thick clumps reduce the effective opacity. This has a pronounced effect on the emergent spectrum. Our modeling for the O-type supergiant zeta Puppis reveals that the optically thin H-alpha line is not affected by wind porosity, but that the PV resonance doublet becomes significantly weaker when macroclumping is taken into account. The reported discrepancies between resonance-line and recombination-line diagnostics can be resolved entirely with the macroclumping modeling without downward revision of the mass-loss rate. Conclusions: Mass-loss rates inferred from optically thin emission, such as the H-alpha line in O stars, are not influenced by macroclumping. The strength of optically thick lines, however, is reduced because of the porosity effects. Therefore, neglecting the porosity in stellar wind modeling can lead to underestimating empirical mass-loss rates.
description: A&A (in press), see full abstract in the text
Design and Development of an Automatic Swine Feeding Machine Cooperated with Radio Frequency Identification Technique
Creators: name: Pullteap, Saroj
Publisher: name: Mahasarakham University
Year: 2013
Subjects: Electronics tag, radio frequency identifi cation technique, microcontroller, automatic feeding machine

description: 1, 32, Journal of SCIENCE and TECHNOLOGY Mahasarakham University
Molecular Switching Operation in Gate Constricted Interface of MoS$_2$ and hBN Heterostructure
Creators: name: Tripathi, Rahul
name: Bhattacharyya, Pritam
name: Nandi, Sukanta
name: Shukla, Alok
name: Misra, Abha
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Combined diverse two-dimensional (2D) materials for semiconductor interfaces are attractive for electrically controllable carrier confinement to enable excellent electrostatic control. We investigated the transport characteristic in heterointerface of multilayer molybdenum disulfide and hexagonal boron nitride (MoS$_2$/h-BN) to reveal that the charge transfer switching (CTS) is highly dependent on both the local gate constriction and bias in the channel. Notably, the CTS is shown to be controlled at a molecular level through electrotunable gated constriction. The resulting significant change in conductance due to exposing 100 parts-per-billion of nitrogen dioxide gas led to a high on/off ratio of 10 2 for completely switching off the channel thus, acting as a molecular switch. First-principle calculations further explained the mechanism of molecular CTS in the device. The molecular tunability of CTS has not been previously reported in any of the van der Waals semiconductor interfaces. Our finding opens avenues to exploit various atomically thin heterostructures for the mesoscopic transport phenomena towards molecular switching operation at room temperature.
description: 29 pages, 5 figures
Stringy Motivic Spectra II: Higher Koszul Duality
Creators: name: Buchanan, Ryan J.
Publisher: name: Zenodo
Year: 2023
Subjects: topology
black holes
work locking
strings
motives
spectra
delooping
adjunction

description: This is a rendition of [2]. We study stringy motivic structures. This builds upon work dealing with $\mathbb{F}_p$-modives for a suitable prime p. In our case, we let p be a long exact sequence spanning a path in a pre-geometric space. We superize a nerve from our previous study.
From operator statistics to wormholes
Creators: name: Altland, Alexander
name: Bagrets, Dmitry
name: Nayak, Pranjal
name: Sonner, Julian
name: Vielma, Manuel
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: For a generic quantum many-body system, the quantum ergodic regime is defined as the limit in which the spectrum of the system resembles that of a random matrix theory (RMT) in the corresponding symmetry class. In this paper we analyse the time dependence of correlation functions of operators. We study them in the ergodic limit as well as their approach to the ergodic limit which is controlled by non-universal massive modes. An effective field theory (EFT) corresponding to the causal symmetry and its breaking describes the ergodic phase. We demonstrate that the resulting Goldstone-mode theory has a topological expansion, analogous to the one described in arXiv:2008.02271 with added operator sources, whose leading non-trivial topologies give rise to the universal ramp seen in correlation functions. The ergodic behaviour of operators in our EFT is seen to result from a combination of RMT-like spectral statistics and Haar averaging over wave-functions. Furthermore we analytically capture the plateau behaviour by taking into account the contribution of a second saddle point. Our main interest are quantum many-body systems with holographic duals and we explicitly establish the validity of the EFT description in the SYK-class of models, starting from their microscopic description. By studying the tower of massive modes above the Goldstone sector we get a detailed understanding of how the ergodic EFT phase is approached and derive the relevant Thouless time scales. We point out that the topological expansion can be reinterpreted in terms of contributions of bulk wormholes and baby-universes.
description: 33 pages, 8 figures, 3 appendices; v2: added some references; v3: published version, improved discussion and figures
Juegos Olímpicos París 2024 y el Turismo.pdf
Creators: name: GRITUR, Grupo de Investigadores en Turismo
name: Quispe Bonilla, Juan Fernando
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 430207
subject: Heritage tourism, visitor and audience studies

description: Los Juegos Olímpicos son más que una competencia deportiva; representan una oportunidad excepcional para las ciudades anfitrionas de convertirse en destinos turísticos de primer nivel y París 2024 nos regaló muchos recuerdos. Desde el 26 de julio hasta el 11 de agosto, la ciudad no solo albergó a atletas de todo el mundo, sino que también atrajo a cientos de miles de turistas. París ha transformado sus calles en escenarios deportivos que resaltan su riqueza cultural y arquitectónica, atrayendo a más de 650,000 turistas durante los días de competición.Este evento ha generado un repunte del 20% en la ocupación hotelera y un incremento del 8% en el tráfico aéreo, impulsando sectores clave como la alimentación, el ocio y la cultura. París 2024 nos mostró cómo los Juegos Olímpicos pueden actuar como un catalizador para el desarrollo turístico y económico. Sin embargo, la afluencia masiva de visitantes puede presentar desafíos, como el "fenómeno de enjambre", que puede afectar negativamente los recursos turísticos y la vida cotidiana de los residentes. El verdadero reto radica en equilibrar los beneficios con los posibles impactos negativos, garantizando que la ciudad continúe brillando en el escenario global mucho después de que concluyan.
Towards understanding how users decide about friendship requests in Online Social Networks
Creators: name: Rashtian, Hootan
Publisher: name: Zenodo
Year: 2014
Subjects: Usable Security
OSN
OSN Security

description: Accepting friend requests from strangers in Facebook-like online social networks  is known to be a risky behavior. Still, empirical evidence suggests that Facebook  users often accept such requests with high rate. As a first step towards technology  support of users in their decisions about friend requests, we investigate why users  accept such requests. We conducted two studies of users' befriending behavior on  Facebook. Based on 20 interviews with active Facebook users, we developed a  friend request acceptance model that explains how various factors influence user  acceptance behavior. To test and refine our model, we also conducted a quantitative  study with 397 participants using Amazon Mechanical Turk. We found that  four factors significantly impact the receiver's decision towards requests sent from  strangers, namely, knowing the requester's in real world, having common hobbies  or interests, having mutual friends, and the closeness of mutual friends. Based on  our findings, we offer design recommendations for improving the usability of the  corresponding user interfaces in order to help users make more informed decisions.
Η λειτουργία των πέντε αισθήσεων και η προοπτική της σωτηρίας κατά τον Άγιο Νεόφυτο:
Creators: name: Μολέσκη, Λοϊζα Α.
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Αισθήσεις
Νεόφυτος
Θέωση
Senses
Neophytos
Theosis

description: Σκοπός της παρούσας διπλωματικής εργασίας είναι να αναλυθεί ο σωστός προσανατολισμός των πέντε αισθήσεων, ως βασικό μέσο της σωτηρίας του ανθρώπου και η θεραπευτική μέθοδος για την πνευματική κάθαρση τους, όπως τον αντιλήφθηκε και τον ανέπτυξε ο Άγιος Νεόφυτος ο Έγκλειστος, μέσα στο θεόπνευστο έργο του, με ένα μοναδικό γλαφυρό και ανεπιτήδευτο τρόπο. Στην καταπληκτική σειρά των συγγραμμάτων του, ο άγιος Νεόφυτος μας περιγράφει τη λειτουργία των αισθήσεων και τον εξαγνισμό τους με απώτερο σκοπό και στόχο ο άνθρωπος να κερδίσει τη θέωση.
description: The aim of this thesis is to analyze the correct orientation of the five senses, as a key instrument of mankind’s salvation as well as the therapeutic method of spiritual cleansing, through the “eyes” of Saint Neophytos the Recluse. In an amazing series of books, the Saint describes the correct use of senses and their purification in order all men to gain the so called “theosis”.
Engineering Access Control For Distributed Enterprise Systems
Creators: name: Beznosov, Konstantin
Publisher: name: Zenodo
Year: 2000

description: Access control (AC) is a necessary defense against a large variety of security attacks on the resources of distributed enterprise applications. However, to be effective, AC in some application domains has to be fine-grain, support the use of application-specific factors in authorization decisions, as well as consistently and reliably enforce organization-wide authorization policies across enterprise applications. Because the existing middleware technologies do not provide a complete solution, application developers resort to embed- ding AC functionality in application systems. This coupling of AC functionality with application logic causes significant problems including tremendously difficult, costly and error prone development, integration, and overall ownership of application software. The way AC for application systems is engineered needs to be changed. In this dissertation, we propose an architectural approach for engineering AC mechanisms to address the above problems. First, we develop a framework for implementing the role- based access control (RBAC) model using AC mechanisms provided by CORBA Security. For those application domains where the granularity of CORBA controls and the expressiveness of RBAC model suffice, our framework addresses the stated problem. In the second and main part of our approach, we propose an architecture for an authorization service, RAD, to address the problem of controlling access to distributed application resources, when the granularity and support for complex policies by middleware AC mechanisms are inadequate. Applying this architecture, we developed a CORBA-based application authorization service (CAAS). Using CAAS, we studied the main properties of the architecture and showed how they can be substantiated by employing CORBA and Java technologies. Our approach enables a wide-ranging solution for controlling the resources of distributed enterprise applications.
Analysis of the SN1987A two-stage explosion hypothesis with account for the MSW neutrino flavour conversion
Creators: name: Lychkovskiy, Oleg
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Detection of 5 events by the Liquid Scintillation Detector (LSD) on February, 23, 1987 was interpreted in the literature as the detection of neutrinos from the first stage of the two-stage supernova collapse. We pose rigid constraints on the properties of the first stage of the collapse, taking into account neutrino flavour conversion due to the MSW-effect and general properties of supernova neutrino emission. The constraints depend on the unknown neutrino mass hierarchy and mixing angle θ_{13}.
description: presented at "Rencontres de Moriond EW 2007", 10-17 March 2007
Shear zones in granular media: 3D Contact Dynamics simulation
Creators: name: Ries, Alexander
name: Unger, Tamas
name: Wolf, Dietrich E.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Shear zone formation is investigated in slow 3D shear flows. We simulate the linear version of the split-bottom shear cell. It is shown that the same type of wide shear zones is achieved in the presence as well as in the absence of gravity. We investigate the relaxation of the material towards a stationary flow and analyze the stress and the velocity fields. We provide the functional form of the widening of the shear zone inside the bulk. We discuss the growth of the region where the material is in critical state. It is found that the growth of the critical zone is responsible for the initial transient of the shear zone.
description: 9 pages
Ancillary science with Ariel: Feasibility and scientific potential of young stellar object observations
Creators: name: Gyűrűs, Boldizsár I.
name: Kiss, Csaba
name: Morales, Juan Carlos
name: Nakhjiri, Navid
name: Marton, Gábor
name: Ábrahám, Péter
name: Kóspál, Ágnes
name: Moór, Attila
name: Szabó, Gyula M.
name: Szabó, Róbert
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: To investigate the feasibility of ancillary target observations with ESA's Ariel mission, we compiled a list of potentially interesting young stars: FUors, systems harbouring extreme debris discs and a larger sample of young stellar objects showing strong near/mid-infrared excess. These objects can be observed as additional targets in the waiting times between the scheduled exoplanet transit and occultation observations. After analyzing the schedule for Ariel an algorithm was constructed to find the optimal target to be observed in each gap. The selection was mainly based on the slew and stabilization time needed to observe the selected YSO, but it also incorporated the scientific importance of the targets and whether they have already been sufficiently measured. After acquiring an adequately large sample of simulation data, it was concluded that approximately 99.2% of the available -- at least one hour long -- gaps could be used effectively. With an average slewing and stabilization time of about 16.7 minutes between scheduled exoplanet transits and ancillary targets, this corresponds to an additional $2881 \pm 56$ hours of active data gathering. When this additional time is used to observe our selected 200 ancillary targets, a typical signal-to-noise ratio of $\sim$10$^4$ can be achieved along the whole spectral window covered by Ariel.
description: Accepted for publication in Experimental Astronomy
MPEC 2024-T50 : 2024 TH
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 TH

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
The classification and interpretation of hardwood ecosystems on the Quinsam Flats, Elk River Tree Farm
Creators: name: Bernardy, Pavel
Publisher: name: University of British Columbia
Year: 2010

description: The vegetation and soils of hardwood ecosystems in the Elk River Tree Farm, near Campbell River, British Columbia, were sampled and analysed, and the ecosystems classified into a hierarchy of vegetation and site units, using the methods of biogeoclimatic ecosystem classification (BEC). Four plant and four site associations were distinguished. Site units were used as a categorical framework for selection of suitable site preparation method, tree species, and planting microsites. A key was developed to assist Fletcher Challenge Canada Ltd. foresters in site identification and regeneration of hardwood forests on a site-specific basis. A pattern of site units in the study area is demonstrated in the form of a 1:5000 map for a selected, 50 ha-segment of a hardwood forest. It is suggested that the hardwood ecosystems have developed and persisted in response to a seasonally fluctuating water table which can be attributed to poor drainage as a function of fine soil texture, flat topography, and winter-high and summer-low precipitation. The soil water table is very high in the winter but absent or very low in the summer. As a result, the rooting zone in the winter is under the influence of poorly oxygenated water. Such a soil moisture regime is not favourable for the growth of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco]. This study makes recommendations for the management of hardwood ecosystems on a site-specific basis.
Integro: Leveraging Victim Prediction for Robust Fake Account Detection in OSNs
Creators: name: Boshmaf, Yazan
name: Logothetis, Dionysios
name: Siganos, Georgos
name: Leria, Jorge
name: Lorenzo, Jose
name: Ripeanu, Matei
name: Beznosov, Konstantin
Publisher: name: Zenodo
Year: 2015
Subjects: Victim prediction
Fake account detection
Socialbots
Online social networks

description: Detecting fake accounts in online social networks (OSNs) protects OSN operators and their users from various malicious activities. Most detection mechanisms attempt to predict and classify user accounts as real (i.e., benign, honest) or fake (i.e., malicious, Sybil) by analyzing user-level activities or graph-level structures. These mechanisms, however, are not robust against adversarial attacks in which fake accounts cloak their operation with patterns resembling real user behavior. We herein demonstrate that victims, benign users who control real accounts and have befriended fakes, form a distinct classification category that is useful for designing robust detection mechanisms. First, as attackers have no control over victim accounts and cannot alter their activities, a victim account classifier which relies on user-level activities is relatively harder to circumvent. Second, as fakes are directly connected to victims, a fake account detection mechanism that integrates victim prediction into graph-level structures is more robust against manipulations of the graph. To validate this new approach, we designed Integro, a scalable defense system that helps OSNs detect automated fake accounts using a robust user ranking scheme. Integro starts by predicting victim accounts from user-level activities. After that, it integrates these predictions into the graph as weights, so that edges incident to predicted victims have much lower weights than others. Finally, Integro ranks user accounts based on a modified random walk that starts from a known real account. Integro guarantees that most real accounts rank higher than fakes so that OSN operators can take actions against low-ranking fake accounts.  We implemented Integro using widely-used, open-source distributed computing platforms in which it scaled nearly linearly. We evaluated Integro against SybilRank, the state-of-the-art in fake account detection, using real-world datasets and a large-scale deployment at Tuenti, the largest OSN in Spain. We show that Integro significantly outperforms SybilRank in user ranking quality, where the only requirement is to employ a victim classifier is better than random. Moreover, the deployment of Integro at Tuenti resulted in up to an order of magnitude higher precision in fake accounts detection, as compared to SybilRank.
Perturbation theory of nearly spherical dielectric optical resonators
Creators: name: Gohsrich, Julius
name: Shah, Tirth
name: Aiello, Andrea
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: Mathematical Physics (math-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Dielectric spheres of various sizes may sustain electromagnetic whispering-gallery modes resonating at optical frequencies with very narrow linewidths. Arbitrary small deviations from the spherical shape typically shift and broaden such resonances. Our goal is to determine these shifted and broadened resonances. A boundary-condition perturbation theory for the acoustic vibrations of nearly circular membranes was developed by Rayleigh more than a century ago. We extend this theory to describe the electromagnetic excitations of nearly spherical dielectric cavities. This approach permits us to avoid dealing with decaying quasinormal modes. We explicitly find the frequencies and the linewidths of the optical resonances for arbitrarily deformed nearly spherical dielectric cavities, as power series expansions by a small parameter, up to and including second-order terms. We thoroughly discuss the physical conditions for the applicability of perturbation theory.
description: 31 pages, 6 figures; published version
Tomography for amplitudes of hard exclusive processes
Creators: name: Polyakov, M. V.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We discuss which part of information about hadron structure encoded in the Generalized Parton Distributions (GPDs) [part of total GPD image] can be restored from the known amplitude of a hard exclusive process. The physics content of this partial image is analyzed. Among other things, we show that this partial image contains direct information about how the target hadron responses to the (string) quark-antiquark operator of {\it arbitrary} spin J. Explicit equations relating physics content of the partial image of GPDs directly to the data are derived. Also some new results concerning the dual parametrization of GPDs are presented.
description: 13 pages, no figures, misprints are corrected
Symmetry in the Painlevé systems and their extensions to four-dimensional systems
Creators: name: Sasano, Yusuke
Publisher: name: arXiv
Year: 2007
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 34M55, 34M45, 58F05, 32S65

description: We give a new approach to the symmetries of the Painlevé equations $P_{V},P_{IV},P_{III}$ and $P_{II}$, respectively. Moreover, we make natural extensions to fourth-order analogues for each of the Painlevé equations $P_{V}$ and $P_{III}$, respectively, which are natural in the sense that they preserve the symmetries.
description: 32 pages, 16 figures
Ultrahigh-energy photons from LHAASO as probes of Lorentz symmetry violations
Creators: name: Li, Chengyi
name: Ma, Bo-Qiang
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The Large High Altitude Air Shower Observatory~(LHAASO) is one of the most sensitive gamma-ray detector arrays currently operating at TeV and PeV energies. Recently the LHAASO experiment detected ultra-high-energy~(UHE; $E_γ\gtrsim 100~\mathrm{TeV}$) photon emissions up to $1.4~\mathrm{PeV}$ from twelve astrophysical gamma-ray sources. We point out that the detection of cosmic photons at such energies can constrain the photon self-decay motivated by superluminal Lorentz symmetry violation~(LV) to a higher level, thus can put strong constraints to certain LV frameworks. Meanwhile, we suggest that the current observation of the PeV-scale photon with LHAASO may provide hints to permit a subluminal type of Lorentz violation in the proximity of the Planckian regime, and may be compatible with the light speed variation at the scale of $3.6\times 10^{17}~\mathrm{GeV}$ recently suggested from gamma-ray burst~(GRB) time delays. We further propose detecting PeV photons coming from extragalactic sources with future experiments, based on LV-induced threshold anomalies of $e^{+}e^{-}$ pair-production, as a crucial test of subluminal Lorentz violation. We comment that these observations are consistent with a D-brane/string-inspired quantum-gravity framework, the space-time foam model.
description: 7 latex pages, final version for publication
Radiative gravitino decays from R-parity violation
Creators: name: Lola, S.
name: Osland, P.
name: Raklev, A. R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study radiative gravitino decay within the framework of R-violating supersymmetry. For trilinear R-violating couplings that involve the third generation of fermions, or for light gravitinos, we find that the radiative loop-decay $\tilde{G} \to γν$ dominates over the tree-level ones for a wide set of parameters. We calculate the gravitino decay width and study its implications for cosmology and collider physics. Slow-decaying gravitinos are good dark matter candidates, for a range of parameters that would also predict observable R-violating signatures in colliders. In general the branching ratios are very dependent on the relative hierarchies of R-violating operators, and may provide relevant information on the flavour structure of the underlying fundamental theory.
description: 17 pages, 5 figures
Security Analysis of Malicious Socialbots on the Web
Creators: name: Boshmaf, Yazan
Publisher: name: Zenodo
Year: 2015
Subjects: Socialbots
Social Botnets
Social Infiltration
Fake Accounts
Graph-based Detection
Feature-based Detection
User Ranking
Online Social Networks
Web Security
Online Privacy

description: The open nature of the Web, online social networks (OSNs) in particular, makes it possible to design socialbots—automation software that controls fake accounts in a target OSN, and has the ability to perform basic activities similar to those of real users. In the wrong hands, socialbots can be used to infiltrate online communities, build up trust over time, and then engage in various malicious activities. This dissertation presents an in-depth security analysis of malicious socialbots on the Web, OSNs in particular. The analysis focuses on two main goals: (1) to characterize and analyze the vulnerability of OSNs to cyber attacks by malicious socialbots, social infiltration in particular, and (2) to design and evaluate a countermeasure to efficiently and effectively defend against socialbots. To achieve these goals, we first studied social infiltration as an organized campaign operated by a socialbot network (SbN)—a group of programmable socialbots that are coordinated by an attacker in a botnet-like fashion. We implemented a prototypical SbN consisting of 100 socialbots and operated it on Facebook for 8 weeks. Among various findings, we observed that some users are more likely to become victims than others, depending on factors related to their social structure. Moreover, we found that traditional OSN defenses are not effective at identifying automated fake accounts or their social infiltration campaigns. Based on these findings, we designed Integro—an infiltration-resilient defense system that helps OSNs detect automated fake accounts via a user ranking scheme. In particular, Integro relies on a novel approach that leverages victim classification for robust graph-based fake account detection, with provable security guarantees. We implemented Integro on top of widely-used, open-source distributed systems, in which it scaled nearly linearly. We evaluated Integro against SybilRank—the state-of-the-art in graph-based fake account detection—using real-world datasets and a large-scale, production-class deployment at Tuenti, the largest OSN in Spain with more than 15 million users. We showed that Integro significantly outperforms SybilRank in ranking quality, allowing Tuenti to detect at least 10 times more fake accounts than their current abuse detection system.
Symmetries of perturbed conformal field theories
Creators: name: Fredenhagen, Stefan
name: Gaberdiel, Matthias R.
name: Keller, Christoph A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The symmetries of perturbed conformal field theories are analysed. We explain which generators of the chiral algebras of a bulk theory survive a perturbation by an exactly marginal bulk field. We also study the behaviour of D-branes under current-current bulk deformations. We find that the branes always continue to preserve as much symmetry as they possibly can, i.e. as much as is preserved in the bulk. We illustrate these findings with several examples, including permutation branes in WZW models and B-type D-branes in Gepner models.
description: 30 pages, 3 figures. V2: Small error in eq. (2.14) corrected
Stellar Mass and Star Formation Rate within a Billion Light-Years
Creators: name: Biteau, J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: To develop galaxy-targeting approaches, the gravitational-wave community built a catalog of stellar mass in the local universe based on the 2MASS spectroscopic and photometric redshift surveys. By cleaning and supplementing this catalog, the present work aims to establish a near-infrared flux-limited sample to map both stellar mass and star formation rate (SFR) over the full sky. The 2MASS spectroscopic and photometric redshift surveys are cross-matched with the HyperLEDA database and the Local Volume sample at d < 11 Mpc, providing a flux-limited sample with revised distance estimates and corrections for incompleteness out to 350 Mpc. Scaling relations with stellar mass as a function of morphology are used to construct a SFR cosmography in the local universe. Stellar mass and SFR densities converge towards values compatible with deep-field observations beyond 100 Mpc. The 3D distribution of these two tracers is consistent with the distribution of matter deduced from cosmic flows. With spectroscopic redshifts available for about half of the ~400,000 galaxies within 350 Mpc and photometric distances with a 12% uncertainty available for the other half, the present sample may find applications in both cosmology and astroparticle physics. The present work provides in particular new bases for modeling the large- and intermediate-scale anisotropies observed at ultra-high energies. The distribution of magnetic fields at Mpc scales, which can be deduced from the 3D distribution of matter, is inferred to be crucial in shaping the ultra-high-energy sky.
description: 28 pages, 5 tables, 15 figures. Matches the published version. Online material available at http://doi.org/10.5281/zenodo.5118697
Muon Physics: A Pillar of the Standard Model
Creators: name: Roberts, B. Lee
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Since its discovery in the 1930s, the muon has played an important role in our quest to understand the sub-atomic theory of matter. The muon was the first second-generation standard-model particle to be discovered, and its decay has provided information on the (Vector -Axial Vector) structure of the weak interaction, the strength of the weak interaction, G_F, and the conservation of lepton number (flavor) in muon decay. The muon's anomalous magnetic moment has played an important role in restricting theories of physics beyond the standard standard model, where at present there is a 3.4 standard-deviation difference between the experiment and standard-model theory. Its capture on the atomic nucleus has provided valuable information on the modification of the weak current by the strong interaction which is complementary to that obtained from nuclear beta decay.
description: 8 pages, 9 figures. Invited paper for the Journal of Physical Society in Japan (JPSJ), Special Topics Issue "Frontiers of Elementary Particle Physics, The Standard Model and beyond"
Particle motion around a static axially symmetric wormhole
Creators: name: Narzilloev, Bakhtiyor
name: Malafarina, Daniele
name: Abdujabbarov, Ahmadjon
name: Ahmedo, Bobomurat
name: Bambi, Cosimo
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We consider the properties of a static axially symmetric wormhole described by an exact solution of Einstein's field equations and investigate how we can distinguish such a hypothetical object from a black hole. To this aim, we explore the motion of test particles and photons in the wormhole's space-time and compare it with the particle dynamics in the well known space-times of Schwarzschild and Kerr black holes. We show that precise simultaneous measurement of test particle motion and photon motion may provide the means to distinguish the wormhole geometry from that of a black hole.
description: 12 pages, 9 figures; v2: refereed version