cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Generalised geometric Brownian motion: Theory and applications to option pricing
Creators: name: Stojkoski, Viktor
name: Sandev, Trifce
name: Basnarkov, Lasko
name: Kocarev, Ljupco
name: Metzler, Ralf
Publisher: name: arXiv
Year: 2020
Subjects: subject: Pricing of Securities (q-fin.PR)
subject: FOS: Economics and business

description: Classical option pricing schemes assume that the value of a financial asset follows a geometric Brownian motion (GBM). However, a growing body of studies suggest that a simple GBM trajectory is not an adequate representation for asset dynamics due to irregularities found when comparing its properties with empirical distributions. As a solution, we develop a generalisation of GBM where the introduction of a memory kernel critically determines the behavior of the stochastic process. We find the general expressions for the moments, log-moments, and the expectation of the periodic log returns, and obtain the corresponding probability density functions by using the subordination approach. Particularly, we consider subdiffusive GBM (sGBM), tempered sGBM, a mix of GBM and sGBM, and a mix of sGBMs. We utilise the resulting generalised GBM (gGBM) to examine the empirical performance of a selected group of kernels in the pricing of European call options. Our results indicate that the performance of a kernel ultimately depends on the maturity of the option and its moneyness.
Mass Spectrum in R-Parity Violating mSUGRA and Benchmark Points
Creators: name: Allanach, B. C.
name: Bernhardt, M. A.
name: Dreiner, H. K.
name: Kom, C. H.
name: Richardson, P.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We investigate in detail the low-energy spectrum of the R-parity violating mSUGRA model using the computer program \texttt{SOFTSUSY}. We impose the experimental constraints from the measurement of the anomalous magnetic moment of the muon, $(g-2)_μ$, the decay $b\ra sγ$ as well as the mass bounds from direct searches at colliders, in particular on the Higgs boson and the lightest chargino. We also include a new calculation for the R parity violating contribution to $\Br(B_s\ra μ^+μ^-)$. We then focus on cases where the lightest neutralino is {\em not} the lightest supersymmetric particle (LSP). In this region of parameter space either the lightest scalar tau (stau) or the scalar tau neutrino (tau sneutrino) is the LSP. We suggest four benchmark points with typical spectra and novel collider signatures for detailed phenomenological analysis and simulation by the LHC collaborations.
description: 19 pages, 11 figures
Density operator approach to turbulent flows in plasma and atmospheric fluids
Creators: name: Zloshchastiev, Konstantin G.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: FOS: Physical sciences

description: We formulate a statistical wave-mechanical approach to describe dissipation and instabilities in two-dimensional turbulent flows of magnetized plasmas and atmospheric fluids, such as drift and Rossby waves. This is made possible by the existence of Hilbert space, associated with the electric potential of plasma or stream function of atmospheric fluid. We therefore regard such turbulent flows as macroscopic wave-mechanical phenomena, driven by the non-Hermitian Hamiltonian operator we derive, whose anti-Hermitian component is attributed to an effect of the environment. Introducing a wave-mechanical density operator for the statistical ensembles of waves, we formulate master equations and define observables: such as the enstrophy and energy of both the waves and zonal flow as statistical averages. We establish that our open system can generally follow two types of time evolution, depending on whether the environment hinders or assists the system's stability and integrity. We also consider a phase-space formulation of the theory, including the geometrical-optic limit and beyond, and study the conservation laws of physical observables. It is thus shown that the approach predicts various mechanisms of energy and enstrophy exchange between drift waves and zonal flow, which were hitherto overlooked in models based on wave kinetic equations.
description: 17 pages, selected paper from the 17th Russian Gravitational Conference - International Conference on Gravitation, Cosmology and Astrophysics (RUSGRAV-17), Saint Petersburg, 28 June - 4 July 2020
Witnessing Macroscopic Entanglement in a Staggered Magnetic Field
Creators: name: Hide, Jenny
name: Son, Wonmin
name: Lawrie, Ian
name: Vedral, Vlatko
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We investigate macroscopic entanglement in an infinite XX spin-1/2 chain with staggered magnetic field, B_l=B+e^{-iπl}b. Using single-site entropy and by constructing an entanglement witness, we search for the existence of entanglement when the system is at absolute zero, as well as in thermal equilibrium. Although the role of the alternating magnetic field b is, in general, to suppress entanglement as do B and T, we find that when T=0, introducing b allows the existence of entanglement even when the uniform magnetic field B is arbitrarily large. We find that the region and the amount of entanglement in the spin chain can be enhanced by a staggered magnetic field.
description: Accepted for publication in Physical Review A, minor changes from previous version. 5 pages, 3 figures
Ποιοτική και ποσοτική ανάλυση του πρωτοκόλλου CoAP με χρήση πιθανοκρατικού ελέγχου μοντέλων:
Creators: name: Μέντα, Βαρβάρα Πασχάλη
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Δίκτυα αισθητήρων
Έλεγχος μοντέλων
CoAP
Wireless Sensor Network
Model checking

description: Αντικείμενο της παρούσας εργασίας είναι αφενός μεν η μελέτη και παρουσίαση των βασικών χαρακτηριστικών του πρωτοκόλλου CoAP και αφετέρου η μοντελοποίησή του στο προγραμματιστικό περιβάλλον του εργαλείου Prism. Το εργαλείο Prism ανήκει στην κατηγορία των εργαλείων ελέγχου μοντέλων με βάση τις πιθανότητες. Απώτερο σκοπό της εργασίας αποτελεί η ποιοτική και ποσοτική ανάλυση της συμπεριφοράς του πρωτοκόλλου σε σχέση με διάφορες παραμέτρους επικοινωνίας. Μεταξύ των παραμέτρων που μελετήθηκαν για την ποιοτική ανάλυση του πρωτοκόλλου περιλαμβάνονται το πλήθος των κόμβων επικοινωνίας και η συχνότητα αποτυχίας αποστολής μηνυμάτων. Όσο αφορά την ποσοτική ανάλυση του πρωτοκόλλου αυτή έγινε με βάση τη συνολική κατανάλωση ενέργειας που απαιτείται για την ολοκλήρωση μιας συνόδου ανταλλαγής μηνυμάτων.
description: The purpose of this paper is firstly the study and presentation of key features of the CoAP protocol and secondly the modeling of it at the programming environment of Prism. The Prism tool belongs to the probabilistic model checking software. The ultimate purpose of the thesis is the qualitative and quantitative analysis of the protocol behavior in connection with various communication parameters. Among the parameters studied for the qualitative protocol analysis are the number of nodes and the packet error rate. As for the quantitative analysis of this protocol, it was based on the total energy consumption which is required for the message exchange.
Multiple timescales in a model for DNA denaturation dynamics
Creators: name: Baiesi, Marco
name: Livi, Roberto
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Biomolecules (q-bio.BM)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: The denaturation dynamics of a long double-stranded DNA is studied by means of a model of the Poland-Scheraga type. We note that the linking of the two strands is a locally conserved quantity, hence we introduce local updates that respect this symmetry. Linking dissipation via untwist is allowed only at the two ends of the double strand. The result is a slow denaturation characterized by two time scales that depend on the chain length $L$. In a regime up to a first characteristic time $τ_1\sim L^{2.15}$ the chain embodies an increasing number of small bubbles. Then, in a second regime, bubbles coalesce and form entropic barriers that effectively trap residual double-stranded segments within the chain, slowing down the relaxation to fully molten configurations, which takes place at $τ_2\sim L^3$. This scenario is different from the picture in which the helical constraints are neglected.
description: 9 pages, 5 figures
Curricular needs of immigrant women in orientational training programs
Creators: name: Chen, Lin
Publisher: name: University of British Columbia
Year: 2009

description: In training programs designed to help immigrant women adapt to Canada, drop-out rates are frequently high and attendance is often low. Investigating some reasons behind this observation was the motivation for this thesis. A literature review revealed that curricula used in existing programs are often developed from experts' understanding of immigrants' needs; research on immigrant women's curricular needs as perceived by themselves is virtually nonexistent. An objective of this thesis was to address this knowledge gap. This study inquired into what curricular needs immigrant women have, how these needs differ, and what relationship exists between the women's backgrounds and their curricular needs. A questionnaire was developed and validated by an expert panel, and then administered to graduates from an orientational training program. Post-survey interviews were conducted. Data were analyzed using frequency distribution, cluster analysis, multivariate analysis of variance (MANOVA), factor analysis, and linear discriminant analysis. It was found that the program, although well received, did not reflect the curricular needs perceived by the immigrant women themselves. Life skills instruction was unwanted by many students while English and computer lessons were in demand. A desire to regain higherquality jobs partially explained the women's curricular needs.
Effects of turbulent environment on self-organized critical behavior: Isotropy vs Anisotropy
Creators: name: Antonov, N. V.
name: Gulitskiy, N. M.
name: Kakin, P. I.
name: Kochnev, G. E.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study a self-organized critical system under influence of turbulent motion of the environment. The system is described by the anisotropic continuous stochastic equation proposed by Hwa and Kardar [{\it Phys. Rev. Lett.} {\bf 62}: 1813 (1989)]. The motion of the environment is modelled by the isotropic Kazantsev--Kraichnan "rapid-change" ensemble for an incompressible fluid: it is Gaussian with vanishing correlation time and the pair correlation function of the form $\proptoδ(t-t') / k^{d+ξ}$, where $k$ is the wave number and $ξ$ is an arbitrary exponent with the most realistic values $ξ= 4/3$ (Kolmogorov turbulence) and $ξ\to 2$ (Batchelor's limit). Using the field-theoretic renormalization group, we find infrared attractive fixed points of the renormalization group equation associated with universality classes, i.e., with regimes of critical behavior. The most realistic values of the spatial dimension $d=2$ and the exponent $ξ=4/3$ correspond to the universality class of pure turbulent advection where the nonlinearity of the Hwa--Kardar (HK) equation is irrelevant. Nevertheless, the universality class where both the (anisotropic) nonlinearity of the HK equation and the (isotropic) advecting velocity field are relevant also exists for some values of the parameters $\varepsilon=4-d$ and $ξ$. Depending on what terms (anisotropic, isotropic, or both) are relevant in specific universality class, different types of scaling behavior (ordinary one or generalized) are established.
Discovery of a nearby twin of SN1987A's nebula around the luminous blue variable HD168625: Was Sk--69 202 an LBV?
Creators: name: Smith, Nathan
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Spitzer images of the luminous blue variable (LBV) candidate HD168625 reveal the existence of a bipolar nebula several times larger than its previously-known equatorial dust torus. The outer nebula of HD168625 has a full extent of about 80 arcsec or 0.85 pc, and one of the lobes has a well-defined polar ring. The nebula is a near twin of the triple-ring system around SN1987A. Because of these polar rings, and accounting for stellar/progenitor luminosity, HD168625 is an even closer twin of SN1987A than the B supergiant Sher 25 in NGC3603. HD168625's nebula was probably ejected during a giant LBV eruption and not during a red supergiant phase, so its similarity to the nebula around SN1987A may open new possibilities for the creation of SN1987A's rings. Namely, the hypothesis that Sk-69 202 suffered an LBV-like eruption would avert the complete surrender of single star models for its bipolar nebula by offering an alternative to an unlikely binary merger scenario. It also hints that LBVs are the likely progenitors of some type II supernovae, and that HD168625's nebula is a good example of a pre-explosion environment.
description: 14 pages, accepted by AJ
Reconstruction of source location in a network of gravitational wave interferometric detectors
Creators: name: Cavalier, F.
name: Barsuglia, M.
name: Bizouard, M. -A.
name: Brisson, V.
name: Clapson, A. -C.
name: Davier, M.
name: Hello, P.
name: Kreckelbergh, S.
name: Leroy, N.
name: Varvella, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: This paper deals with the reconstruction of the direction of a gravitational wave source using the detection made by a network of interferometric detectors, mainly the LIGO and Virgo detectors. We suppose that an event has been seen in coincidence using a filter applied on the three detector data streams. Using the arrival time (and its associated error) of the gravitational signal in each detector, the direction of the source in the sky is computed using a chi^2 minimization technique. For reasonably large signals (SNR>4.5 in all detectors), the mean angular error between the real location and the reconstructed one is about 1 degree. We also investigate the effect of the network geometry assuming the same angular response for all interferometric detectors. It appears that the reconstruction quality is not uniform over the sky and is degraded when the source approaches the plane defined by the three detectors. Adding at least one other detector to the LIGO-Virgo network reduces the blind regions and in the case of 6 detectors, a precision less than 1 degree on the source direction can be reached for 99% of the sky.
description: Accepted in Phys. Rev. D
Η εφοδιαστική της υποστήριξης των ερευνών και της παραγωγής υδρογονανθράκων σε θαλάσσιο χώρο (Upstream logistics). H περίπτωση της Ελλάδας
Creators: name: Μπόνας, Δημοσθένης Δημητρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Εφοδιαστική αλυσίδα
Υδρογονάνθρακες
Πλοία εφοδιασμού
Oil and gas
Upstream logistics
Offshore supply vessels

description: Στην παρούσα διπλωματική εργασία πραγματοποιείται μία ανάλυση του κλάδου ‘’upstream’’ της βιομηχανίας των υδρογονανθράκων. Η εργασία εκπονήθηκε στα πλαίσια του διατμηματικού προγράμματος μεταπτυχιακών σπουδών ‘’Σχεδιασμός, Οργάνωση και Διαχείριση Συστημάτων Μεταφορών’’ της Πολυτεχνικής Σχολής του Αριστοτελείου Πανεπιστημίου Θεσσαλονίκης. Μέσα από βιβλιογραφική έρευνα αναλύεται η εφοδιαστική αλυσίδα υδρογονανθράκων που αφορά στην Έρευνα & Παραγωγή. Γίνεται αναφορά στα κύρια στάδια Έρευνας και Παραγωγής υδρογονανθράκων με περιγραφή των βασικών στοιχείων μεθοδολογίας και του εξοπλισμού που χρησιμοποιείται. Επιπρόσθετα, γίνεται διεξοδική ανάλυση των πλοίων εφοδιασμού, τα οποία αποτελούν θεμελιώδες στοιχείο των logistics στις ‘’upstream’’ εφοδιαστικές αλυσίδες. Στη συνέχεια παρατίθεται μία ανασκόπηση των ερευνών υδρογονανθράκων στον Ελλαδικό χώρο καθώς επίσης και οι πρόσφατες εξελίξεις. Τέλος, με χρήση της μεθοδολογίας Analytical Hierarchy Process (AHP) γίνεται επιλογή λιμανιού υποστήριξης και εφοδιασμού για τα υπό παραχώρηση οικόπεδα παραγωγής υδρογονανθράκων στη Δυτική Ελλάδα
description: In this master’s thesis, an analysis of the upstream sector of the oil and gas industry is presented. The study was conducted in the frame of the master programme ‘’ Planning, Organization and Management of Transport Systems’’, Aristotle University of Thessaloniki, School of Engineering & Technology. After a literature review, the supply chain of the upstream oil and gas industry is being analyzed. There is a major reference on the basic stages of oil and gas exploration and production, as well as on the fundamentals of methodology being followed and the equipment used. In addition, an extensive review of the operations supply vessels (OSV) is carried out, since they constitute a fundamental element in the upstream logistics. Then, a review on the oil and gas research in Greece is cited. In particular, the latest progress on these topics is mentioned. Using the Αnalytical Hierarchy Process method, a supply port is chosen in order to support the production in the under concession fields of Western Greece
A spinorial perspective on massless photons
Creators: name: Esposito, Giampiero
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We exploit the fact that, in Minkowski space-time, gamma matrices are possibly more fundamental than the metric to describe how gauge invariance at perturbative level enforces a Lagrangian for spinor electrodynamics with massless photons. The term quadratic in the potential arises naturally in the gauge-fixed Lagrangian but has vanishing coefficient.
description: 5 pages, Plain Tex
MPEC 2024-T139 : 2024 TC3
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 TC3

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.
Dense planetary rings and the viscous overstability
Creators: name: Latter, Henrik N.
name: Ogilvie, Gordon I.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: This paper examines the onset of the viscous overstability in dense particulate rings. First, we formulate a dense gas kinetic theory that is applicable to the Saturnian system. Our model is essentially that of Araki and Tremaine (1986), which we show can be both simplified and generalised. Second, we put this model to work computing the equilibrium properties of dense planetary rings, which we subsequently compare with the results of N-body simulations, namely those of Salo (1991). Finally, we present the linear stability analyses of these equilibrium states, and derive criteria for the onset of viscous overstability in the self-gravitating and non-self-gravitating cases. These are framed in terms of particle size, orbital frequency, optical depth, and the parameters of the collision law. Our results compare favourably with the simulations of Salo et al. (2001). The accuracy and practicality of the continuum model we develop encourages its general use in future investigations of nonlinear phenomena.
description: Accepted in Icarus; 58 pages; 15 figures
McStas (i): Introduction, use, and basic principles for ray-tracing simulations
Creators: name: Willendrup, P. K.
name: Lefmann, K.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present an overview of, and an introduction to, the general-purpose neutron simulation package McStas. We present the basic principles behind Monte Carlo ray-tracing simulations of neutrons performed in the package and present a few simple examples. We present the implementation of McStas, the status of the package and its use in the neutron community. Finally, we briefly discuss the planned development of the package.
description: 4 figures
Cotunneling through quantum dots coupled to magnetic leads: zero-bias anomaly for non-collinear magnetic configurations
Creators: name: Weymann, Ireneusz
name: Barnas, Jozef
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Cotunneling transport through quantum dots weakly coupled to non-collinearly magnetized leads is analyzed theoretically by means of the real-time diagrammatic technique. The electric current, dot occupations, and dot spin are calculated in the Coulomb blockade regime and for arbitrary magnetic configuration of the system. It is shown that an effective exchange field exerted on the dot by ferromagnetic leads can significantly modify the transport characteristics in non-collinear magnetic configurations, in particular the zero-bias anomaly found recently for antiparallel configuration. For asymmetric Anderson model, the exchange field gives rise to precession of the dot spin, which leads to a nonmonotonic dependence of the differential conductance and tunnel magnetoresistance on the angle between magnetic moments of the leads. An enhanced differential conductance and negative TMR are found for certain non-collinear configurations.
description: 12 pages, 9 figgures
A Robust and Domain-Adaptive Approach for Low-Resource Named Entity Recognition
Creators: name: Yu, Houjin
name: Mao, Xian-Ling
name: Chi, Zewen
name: Wei, Wei
name: Huang, Heyan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Recently, it has attracted much attention to build reliable named entity recognition (NER) systems using limited annotated data. Nearly all existing works heavily rely on domain-specific resources, such as external lexicons and knowledge bases. However, such domain-specific resources are often not available, meanwhile it's difficult and expensive to construct the resources, which has become a key obstacle to wider adoption. To tackle the problem, in this work, we propose a novel robust and domain-adaptive approach RDANER for low-resource NER, which only uses cheap and easily obtainable resources. Extensive experiments on three benchmark datasets demonstrate that our approach achieves the best performance when only using cheap and easily obtainable resources, and delivers competitive results against state-of-the-art methods which use difficultly obtainable domainspecific resources. All our code and corpora can be found on https://github.com/houking-can/RDANER.
description: Best Student Paper of 2020 IEEE International Conference on Knowledge Graph (ICKG)
Constraints on SUSY Seesaw from Leptogenesis and LFV
Creators: name: Albino, S.
name: Deppisch, F.
name: Rückl, R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study constraints on the fundamental parameters of supersymmetric type I seesaw models imposed by neutrino data, charged lepton flavor violation, thermal leptogenesis and perturbativity of the neutrino Yukawa couplings.
description: 4 pages, 2 figures, to appear in Proceedings of SUSY06, the 14th International Conference on Supersymmetry and the Unification of Fundamental Interactions, UC Irvine, California, 12-17 June 2006
Το ζήτημα της ευθανασίας στα πλαίσια του Ποινικού Δικαίου:
Creators: name: Πλακόπουλος, Αγγελος Ιωάννη
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Ευθανασία
Ανθρωποκτονία
Αυτοδιάθεση της ζωής
Euthanasia
Homicide
Self-determination of life

description: Στην παρούσα εργασία μας απασχόλησε το ζήτημα της ευθανασίας αποκλειστικά στα πλαίσια του Ποινικού Δικαίου. Ξεκινήσαμε προσπαθώντας να προσεγγίσουμε την έννοια της ευθανασίας και αναφερθήκαμε σύντομα στην διαδρομή της μέσα στην ιστορία της ανθρωπότητας. Καθώς μία πράξη ευθανασίας προσβάλλει το ατομικό έννομο αγαθό της ζωής, κρίναμε χρήσιμο να διερευνήσουμε: α) το πότε επέρχεται ο θάνατος με βάση τα πορίσματα της Ιατρικής και τις θέσεις της νομικής επιστήμης επί του θέματος και β) αν ένα δικαίωμα στο θάνατο αναγνωρίζεται στις περιπτώσεις της αυτοκτονίας και της ετεροπροσβολής της ζωής με συναίνεση του θύματος. Επίσης, εξετάσαμε μήπως υπάρχει κάποια διάταξη στον Ελληνικό Ποινικό Κώδικα, που καλύπτει τις περιπτώσεις ευθανασίας, εμμένοντας κυρίως στο άρθρο 300 ΠΚ για την ανθρωποκτονία με συναίνεση και στα επιμέρους στοιχεία του. Στη συνέχεια αναλύσαμε μία προς μία τις μορφές, με τις οποίες εμφανίζεται (ευθεία , έμμεση ενεργητική και παθητική ευθανασία) αλλά και ειδικότερες περιπτώσεις (κατά κυριολεξία ευθανασία, αποσύνδεση από μηχάνημα τεχνητής διατήρησης της ζωής, πρόωρη θανάτωση νεογνών, συμμετοχή σε αυτοκτονία). Τέλος, παραθέσαμε τις νομοθεσίες άλλων Ευρωπαϊκών κρατών (Ολλανδία, Βέλγιο, Λουξεμβούργο), που έχουν νομιμοποιήσει την ευθεία ενεργητική ευθανασία και ερευνήσαμε αν υπάρχει δυνατότητα προσαρμογής αντίστοιχων διατάξεων στην ελληνική έννομη τάξη.
description: In the present dissertation the issue that concerned us was that of euthanasia, strictly within the context of Criminal Law. Initially, we attempted to determine the significance of euthanasia and briefly reviewed its path throughout the history of humanity. As the act of euthanasia affects the individual legal interest of life, it was deemed appropriate to explore: a) the moment a death occurs, based on the conclusions of Medicine and the stance of jurisprudence concerning the matter and b) whether the right to death is recognized in the cases of suicide and insult to life with the consent of the victim. We further examined whether any articles exist in the Greek Penal Code which cover the cases of euthanasia, mainly focusing on article number 300 of the Greek Penal Code on homicide with consent, and any particularly relevant elements. We then proceeded to individually analyse the forms of euthanasia (direct, indirect, active and passive euthanasia) and other more specific cases (literal euthanasia, disconnection from artificial life support machines, euthanasia of newborn babies, participation in suicide ). Last but not least, we stated the laws of other European countries (The Netherlands, Belgium, Luxembourg) that have legalized direct active euthanasia, and examined the possibility of adapting similar acts to the Greek legal system
Probing the Fundamental Symmetries of the Early Universe: The Low Energy Frontier
Creators: name: Ramsey-Musolf, M. J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Searching for the fundamental symmetries that characterize the particle physics of the early universe lies at the forefront of particle physics, nuclear physics, and cosmology. In this talk, I review low energy probes of these symmetries and discuss what they may teach us about what lies beyond the fundamental symmetries of the Standard Model.
description: Plenary Talk, PANIC05 (Sante Fe, NM). 11 pages, no figures
Bayesian Analysis of Static Light Scattering Data for Globular Proteins
Creators: name: Yin, Fan
name: Khago, Domarin
name: Martin, Rachel W.
name: Butts, Carter T.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Applications (stat.AP)
subject: Methodology (stat.ME)
subject: FOS: Computer and information sciences

description: Static light scattering is a popular physical chemistry technique that enables calculation of physical attributes such as the radius of gyration and the second virial coefficient for a macromolecule (e.g., a polymer or a protein) in solution. The second virial coefficient is a physical quantity that characterizes the magnitude and sign of pairwise interactions between particles, and hence is related to aggregation propensity, a property of considerable scientific and practical interest. Estimating the second virial coefficient from experimental data is challenging due both to the degree of precision required and the complexity of the error structure involved. In contrast to conventional approaches based on heuristic OLS estimates, Bayesian inference for the second virial coefficient allows explicit modeling of error processes, incorporation of prior information, and the ability to directly test competing physical models. Here, we introduce a fully Bayesian model for static light scattering experiments on small-particle systems, with joint inference for concentration, index of refraction, oligomer size, and the second virial coefficient. We apply our proposed model to study the aggregation behavior of hen egg-white lysozyme and human gammaS-crystallin using in-house experimental data. Based on these observations, we also perform a simulation study on the primary drivers of uncertainty in this family of experiments, showing in particular the potential for improved monitoring and control of concentration to aid inference.
Scalar field quasinormal modes of noncommutative high dimensional Schwarzschild-Tangherlini black hole spacetime with smeared matter sources
Creators: name: Yan, Zening
name: Wu, Chen
name: Guo, Wenjun
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We investigate the massless scalar quasinormal modes (QNMs) of the noncommutative $D$-dimensional Schwarzschild-Tangherlini black hole spacetime in this paper. By using the Wentzel-Kramers-Brillouin (WKB) approximation method, the asymptotic iterative method (AIM) and the inverted potential method (IPM) method, we made a detail analysis of the massless scalar QNM frequencies by varying the general smeared matter distribution and the allowable characteristic parameters ($k$ and $θ$) corresponding to different dimensions. It is found that the nonconvergence of the high order WKB approximation exists in the QNMs frequencies of scalar perturbation around the noncommutative $D$-dimensional Schwarzschild black holes. We conclude that the 3rd WKB result should be more reliable than those of the high order WKB method since our numerical results are also verified by the AIM method and the IPM method. In the dimensional range of $4\leq D \leq7$, the scalar QNMs as a function of the different papameters (the noncommutative parameter $θ$, the smeared matter distribution parameter $k$, the multipole number $l$ and the main node number $n$) are obtained. Moreover, we study the dynamical evolution of a scalar field in the background of the noncommutative high dimensional Schwarzschild-Tangherlini black hole.
description: 26 pages, 11 figures, to be appeared in Nucl. phys. B
Relations between ISM tracers in galaxies
Creators: name: Galletta, G.
name: Casasola, V.
name: Piovan, L.
name: Merlin, E.
name: Bettoni, D.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We study the relations existing between fluxes emitted at CO(1-0) line, 60 and 100 micron wavelengths, B and soft X-ray wavebands for galaxies of all morphological types. The large set of data that we created allows to revisit some of known relations existing between the different tracers of the Interstellar Medium (ISM): the link between the FIR flux and the CO line emission, the relation between X-ray emission in non active galaxies and the blue or FIR luminosity. Using catalogues of galaxies and works presented in the literature, we collected fluxes in FIR, 21 cm, CO(0-1) line and soft X-ray for two samples, consisting of normal and interacting galaxies respectively. Joining together these samples, we have data for a total of 2953 galaxies, not all observed in the four above wavebands. All the relations found are discussed in the frame of the star formation activity that is the link for most of them. We note that when an active star formation is present, it may link the galaxy fluxes at almost all wavelengths, from X to microwaves. On the contrary, in early-type galaxies where the current star formation rate has faded out the X-FIR fluxes link disappears. This result obtained for early-type galaxies is discussed and explained in detail in the frame of a suitable theoretical model, obtained coupling chemo-dynamical N-body simulations with a dusty spectrophotometric code of population synthesis.
description: 15 pages, 14 figures and 1 table
Αναγνώριση συστημάτων με δεδομένη συνεχή και κρουστική συμπεριφορά.:
Creators: name: Ελευθερίου, Χρυσούλα Βασιλείου
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Πολυωνυμικός Πίνακας
Ομαλές λύσεις
Μη ομαλές λύσεις
Polynomial matrix
Smooth solutions
Impulsive solutions

description: Στην παρούσα εργασία μελετάται ο χώρος λύσεων του ομογενούς συστήματος των αλγεβρικών και διαφορικών εξισώσεων. Ο χώρος των λύσεων κατασκευάζεται τόσο με τη βοήθεια των πεπερασμένων ζευγών Jordan παράγοντας τις λεγόμενες ομαλές λύσεις, όσο και με τη βοήθεια των απείρων ζευγών Jordan δίνοντας μας τις λεγόμενες μη ομαλές λύσεις. Στη συνέχεια προτείνονται δύο τρόποι κατασκευής του ‘αντίστροφου’ προβλήματος τόσο στο χώρο ομαλών όσο και μη ομαλών λύσεων, δηλαδή της εύρεσης του συστήματος αλγεβρικών και διαφορικών εξισώσεων που παράγουν τους συγκεκριμένους χώρους λύσεων.
description: The present paper studies the solution space of the homogenous system of algebraic and differential equations. The solution space could be constructed with the help of finite Jordan pairs extracting the, so called, smooth solutions or with the help of infinite Jordan pairs extracting the, so called, impulsive solutions. Subsequently, we define two ways of approaching the ‘inverse’ problem, i.e. knowing the smooth or impulsive behavior of the homogenous system, we extract the algebraic and differential equations of the specific solution space.
Η ανοιχτού κώδικα εφαρμογή οδήγησης Carmate:
Creators: name: Κολοφωτιάς, Βάιος Βασιλείου
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Λογισμικό Ανοιχτού Κώδικα
Συνοδήγηση
Εφαρμογές Διαδικτύου
Open Source Software
Carpooling
Web
Application

description: Ο βασικός στόχος της παρούσας διπλωματικής εργασίας είναι η παρουσίαση των εργαλείων και τεχνικών που χρησιμοποιήθηκαν για την ανάπτυξη της πλατφόρμας συνοδήγησης CarMate. H συγκεκριμένη πλατφόρμα αναπτύχθηκε με την χρήση μόνο εργαλείων ανοιχτού κώδικα και το σύνολο της διατίθεται υπό την άδεια ελεύθερου λογισμικού GPL version 3. Αρχικά, περιγράφεται η ιδέα, πάνω στην οποία βασίστηκε η ανάπτυξη της πλατφόρμας και οι ανάγκες που σχεδιάστηκε να καλύψει. Στη συνέχεια, γίνεται μια επισκόπηση εννοιών του ελεύθερου λογισμικού και των τεχνικών υποδομών(εξυπηρετητής, βάση δεδομένων, γλώσσες προγραμματισμού) που επιλέχθηκαν για την υποστήριξη της πλατφόρμας. Επίσης, παρουσιάζονται όλα τα εργαλεία ανοιχτού κώδικα που χρησιμοποιήθηκαν για την ανάπτυξη της και αναλύεται η λειτουργικότητα των βασικότερων σελίδων της. Ακόμη, παρουσιάζεται η εφαρμογή για κινητά τηλέφωνα Boleia app και προτάσεις συνεργασίας με το carmate. Τέλος, παρουσιάζονται ενέργειες που έγιναν ώστε η πλατφόρμα να γίνει ευρύτερα γνωστή στο κοινωνικό σύνολο και επεκτάσεις που έγιναν σε αυτή από τρίτους.
description: The main objective of this thesis, is to present the tools and techniques used to develop the carpooling platform CarMate. This platform was developed using only open source tools and the total is available under the free software license GPL version 3. Initially, the idea on which the development of the platform was based on is described and also the needs designed to cover. Then, there is an overview of the concepts of free software and technical infrastructure (server, database, programming languages) chosen to support the platform. Also, there are presented all the open source tools used for the development and then we analyze the functionality of the main pages. It also includes the mobile application Boleia app and proposals for cooperation with carmate. Finally, there are actions presented for the platform to become widely known in the community and extensions made to it by third parties.
$D^\ast$ Polarization as an Additional Constraint on New Physics in the $b\to cτ\barν_τ$ Transition
Creators: name: Ivanov, Mikhail A.
name: Körner, Jürgen G.
name: Santorelli, Pietro
name: Tran, Chien-Thang
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Measurements of the branching fractions of the semileptonic decays $B\to D^{(*)}τ\barν_τ$ and $B_c\to J/ψτ\barν_τ$ systematically exceed the Standard Model (SM) predictions, pointing to possible signals of new physics that can violate lepton flavor universality. The unknown origin of new physics realized in these channels can be probed using a general effective Hamiltonian constructed from four-fermion operators and the corresponding Wilson coefficients. Previously, constraints on these Wilson coefficients were obtained mainly from the experimental data for the branching fractions. Meanwhile, polarization observables were only theoretically studied. The situation has changed with more experimental data having become available, particularly those regarding the polarization of the tau and the $D^*$ meson. In this study, we discuss the implications of the new data on the overall picture. We then include them in an updated fit of the Wilson coefficients using all hadronic form factors from our covariant constituent quark model. The use of our form factors provides an analysis independent of those in the literature. Several new-physics scenarios are studied with the corresponding theoretical predictions provided, which are useful for future experimental studies.
description: 21 pages, 7 figures, 2019 Helmholtz International Summer School (HISS)-Dubna International Advanced School of Theoretical Physics (DIAS-TH)-Quantum Field Theory at the Limits: From Strong Fields to Heavy Quarks
Η χρήση του διαδραστικού πίνακα στο μάθημα της Αρχαίας Ελληνικής Γλώσσας:
Creators: name: Παρλαμπά, Αρτεμις-Μαρία Ιωάννη
Publisher: name: Aristotle University of Thessaloniki
Year: 2014
Subjects: Διαδραστικός
Μαυροπίνακας
Παρατήρηση
Interactive
Blackboard
Observation

description: Η παρούσα διατριβή εντάσσεται στο πλαίσιο του προβληματισμού σε σχέση με τις Τεχνολογίες της Πληροφορίας και της Επικοινωνίας και συγκεκριμένα σε σχέση με το ρόλο τους στην εκπαίδευση. Ειδικότερα, επιχειρεί να μελετήσει εις βάθος ένα νέο διδακτικό μέσο, το Διαδραστικό πίνακα (ΔΠ), και να τον συγκρίνει με τον παραδοσιακό απλό «μαυροπίνακα». Αρχικά επιχειρείται η ερμηνεία και η εξήγηση του όρου «Διαδραστικός πίνακας» και καταγράφεται μια σύντομη ιστορική αναδρομή αυτού. Έπειτα γίνεται αναφορά στις μεθόδους διδασκαλίας, στους τρόπους χρήσης και στα διδακτικά σενάρια που υλοποιήθηκαν στην Ελλάδα και στο διεθνή χώρο από εκπαιδευτικούς που χρησιμοποίησαν στην εκπαιδευτική πράξη το Διαδραστικό πίνακα ως διδακτικό μέσο, ενώ στη συνέχεια παρουσιάζονται τα ερευνητικά πορίσματα που προκύπτουν από τη βιβλιογραφική ανασκόπηση σχετικά με τα πλεονεκτήματα και τα μειονεκτήματα της διδασκαλίας με το Διαδραστικό πίνακα. Στο δεύτερο μέρος της διατριβής, το ερευνητικό, εφαρμόζεται η σύζευξη του ποιοτικού και του ποσοτικού παραδείγματος. Σκοπός της έρευνας είναι να διερευνηθεί, αν υπάρχουν διαφορές μεταξύ της χρήσης του ΔΠ και του απλού «μαυροπίνακα» στην εκπαιδευτική διαδικασία, όσον αφορά στη διάδραση μεταξύ εκπαιδευτικού και μαθητών, στη διάδραση των μαθητών μεταξύ τους, στη χρήση έντυπου υλικού, στην κινητοποίηση των μαθητών, στη χρήση και παρακολούθηση οπτικοακουστικού υλικού και στον τρόπο χρησιμοποίησης των δύο πινάκων.
description: The present thesis is integrated at a context of questioning the Information and Communication Technologies and moreover their part in education. Specifically, the thesis attempts to study in depth a new educational implement, the Interactive Whiteboard (IW), and to compare it to the traditional "blackboard". Firstly, it is attempted to interpret and exlpain the term "Interactive Whiteboard" and to follow its’ history line. Furthermore, there is a mention at the teaching methods, the ways of use and the teaching scenarios that took place in both Greece and internationally by teachers who used the IW as a teaching implement, while afterwards, the findings of the bibliographical study are presented in relation to the advantages and the disadvantages of teaching with the IW. At the second part of the thesis, the research part, a merge is attempted between the qualitative and the quantitative study. The main aim of the study is to examine, if there are differences between the use of the IW and the typical blackboard at the educational process, regarding the interaction between teacher and students, the interaction among the students, the use of printed material, the activation of the students, the use and attendance of audiovisual material and the way the two boards are utilized.
Response to perturbations for granular flow in a hopper
Creators: name: Wambaugh, John F.
name: Matthews, John V.
name: Gremaud, Pierre A.
name: Behringer, Robert P.
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: We experimentally investigate the response to perturbations of circular symmetry for dense granular flow inside a three-dimensional right-conical hopper. These experiments consist of particle tracking velocimetry for the flow at the outer boundary of the hopper. We are able to test commonly used constitutive relations and observe granular flow phenomena that we can model numerically. Unperturbed conical hopper flow has been described as a radial velocity field with no azimuthal component. Guided by numerical models based upon continuum descriptions, we find experimental evidence for secondary, azimuthal circulation in response to perturbation of the symmetry with respect to gravity by tilting. For small perturbations we can discriminate between constitutive relations, based upon the agreement between the numerical predictions they produce and our experimental results. We find that the secondary circulation can be suppressed as wall friction is varied, also in agreement with numerical predictions. For large tilt angles we observe the abrupt onset of circulation for parameters where circulation was previously suppressed. Finally, we observe that for large tilt angles the fluctuations in velocity grow, independent of the onset of circulation.
description: 10 pages, 11 figures (revised for publication)
Chandra observations of the newly discovered magnetar Swift J1818.0-1607
Creators: name: Blumer, Harsha
name: Safi-Harb, Samar
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Swift J1818.0-1607 is a new radio-loud magnetar discovered by the Swift Burst Alert Telescope on 2020 March 12. It has a magnetic field B~2.5e14 G, spin-down luminosity of 7.2e35 ergs/s, and characteristic age of ~470yr. Here we report on the Chandra observations of Swift J1818.0-1607, which allowed for a high-resolution imaging and spectroscopic study of the magnetar and its environment. The 1-10 keV spectrum of the magnetar is best described by a single blackbody model with a temperature of 1.2\pm0.1 keV and an unabsorbed flux of 1.9e-11 ergs/cm^2/s. This implies an X-ray luminosity of ~9.6e34 ergs/s and an efficiency of ~0.13 at a distance of 6.5 kpc. The Chandra image also shows faint diffuse emission out to >10" from the magnetar, with its spectrum adequately described by a powerlaw with a photon index of 2.0\pm0.5 and a luminosity of ~8.1e33 ergs/s. The extended emission is likely dominated by a dust scattering halo and future observations of the source in quiescence will reveal any underlying compact wind nebula. We conclude that Swift J1818.0-1607 is a transient source showing properties between high-B pulsars and magnetars, and could be powered at least partly by its high spin-down similar to the rotation-powered pulsars.
description: Accepted for publication in the Astrophysical Journal Letters, 6 pages, 1 table, 4 figures
A Review of Leading Quantum Gravitational Corrections to Newtonian Gravity
Creators: name: Akhundov, Arif
name: Shiekh, Anwar
Publisher: name: arXiv
Year: 2006
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this review we present the theoretical background for treating General Relativity as an effective field theory and focus on the concrete results of such a treatment. As a result we present the calculations of the low-energy leading gravitational corrections to the Newtonian potential between two sources.
description: 21 pages, 18 figures (references added)
Generalization of Friedberg-Lee Symmetry
Creators: name: Huang, Chao-Shang
name: Li, Tianjun
name: Liao, Wei
name: Zhu, Shou-Hua
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study the possible origin of Friedberg-Lee symmetry. First, we propose the generalized Friedberg-Lee symmetry in the potential by including the scalar fields in the field transformations, which can be broken down to the FL symmetry spontaneously. We show that the generalized Friedberg-Lee symmetry allows a typical form of Yukawa couplings, and the realistic neutrino masses and mixings can be generated via see-saw mechanism. If the right-handed neutrinos transform non-trivially under the generalized Friedberg-Lee symmetry, we can have the testable TeV scale see-saw mechanism. Second, we present two models with the $SO(3)\times U(1)$ global flavour symmetry in the lepton sector. After the flavour symmetry breaking, we can obtain the charged lepton masses, and explain the neutrino masses and mixings via see-saw mechanism. Interestingly, the complete neutrino mass matrices are similar to those of the above models with generalized Friedberg-Lee symmetry. So the Friedberg-Lee symmetry is the residual symmetry in the neutrino mass matrix after the $SO(3)\times U(1)$ flavour symmetry breaking.
description: 16 pages, no figure, version published in PRD