cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Multimodal Mobility Systems: Joint Optimization of Transit Network Design and Pricing
Creators: name: Luo, Qi
name: Samaranayake, Samitha
name: Banerjee, Siddhartha
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Systems and Control (eess.SY)
subject: Optimization and Control (math.OC)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Mathematics

description: The performance of multimodal mobility systems relies on the seamless integration of conventional mass transit services and the advent of Mobility-on-Demand (MoD) services. Prior work is limited to individually improving various transport networks' operations or linking a new mode to an existing system. In this work, we attempt to solve transit network design and pricing problems of multimodal mobility systems en masse. An operator (public transit agency or private transit operator) determines the frequency settings of the mass transit system, flows of the MoD service, and prices for each trip to optimize the overall welfare. A primal-dual approach, inspired by the market design literature, yields a compact mixed integer linear programming (MILP) formulation. However, a key computational challenge remains in allocating an exponential number of hybrid modes accessible to travelers. We provide a tractable solution approach through a decomposition scheme and approximation algorithm that accelerates the computation and enables optimization of large-scale problem instances. Using a case study in Nashville, Tennessee, we demonstrate the value of the proposed model. We also show that our algorithm reduces the average runtime by 60\% compared to advanced MILP solvers. This result seeks to establish a generic and simple-to-implement way of revamping and redesigning regional mobility systems in order to meet the increase in travel demand and integrate traditional fixed-line mass transit systems with new demand-responsive services.
description: '21 ACM/IEEE International Conference on Cyber-Physical Systems
Black holes with topological charges in Chern-Simons AdS$_5$ supergravity
Creators: name: Andrianopoli, Laura
name: Giribet, Gaston
name: Díaz, Darío López
name: Miskovic, Olivera
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study static black hole solutions with locally spherical horizons coupled to non-Abelian field in $\mathcal{N}=4$ Chern-Simons AdS$_5$ supergravity. They are governed by three parameters associated to the mass, axial torsion and amplitude of the internal soliton, and two ones to the gravitational hair. They describe geometries that can be a global AdS space, naked singularity or a (non-)extremal black hole. We analyze physical properties of two inequivalent asymptotically AdS solutions when the spatial section at radial infinity is either a 3-sphere or a projective 3-space. An important feature of these 3-parametric solutions is that they possess a topological structure including two $SU(2)$ solitons that wind nontrivially around the black hole horizon, as characterized by the Pontryagin index. In the extremal black hole limit, the solitons' strengths match and a soliton-antisoliton system unwinds. That limit admits both non-BPS and BPS configurations. For the latter, the pure gauge and non-pure gauge solutions preserve $1/2$ and $1/16$ of the original supersymmetries, respectively. In a general case, we compute conserved charges in Hamiltonian formalism, finding many similarities with standard supergravity black holes.
description: 81 pages, no figures; in v2 references added, text improved; version to appear in JHEP
Thermal Dilepton Production from Dropping rho in the Vector Manifestation
Creators: name: Harada, M.
name: Sasaki, C.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We study the pion electromagnetic form factor and the dilepton production rate in hot matter based on the vector manifestation (VM) of chiral symmetry in which the massless vector meson becomes the chiral partner of the pion, giving a theoretical framework of the dropping $ρ$ \^^ a la Brown-Rho scaling. The VM predicts a strong violation of the vector dominance (VD) near the phase transition point associated with the dropping $ρ$. We present the effect of the VD violation to the dilepton production rate and make a comparison to the one predicted by assuming the VD together with the dropping $ρ$.
description: 6 pages, 2 figures, contribution to the proceedings of the 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (QM2006), November 14-20 2006, Shanghai, China
Magellan Spectroscopy of AGN Candidates in the COSMOS Field
Creators: name: Trump, Jonathan R.
name: Impey, Chris D.
name: McCarthy, Patrick J.
name: Elvis, Martin
name: Huchra, John P.
name: Brusa, Marcella
name: Hasinger, Gunther
name: Schinnerer, Eva
name: Capak, Peter
name: Lilly, Simon J.
name: Scoville, Nick Z.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present spectroscopic redshifts for the first 466 X-ray and radio-selected AGN targets in the 2 deg^2 COSMOS field. Spectra were obtained with the IMACS instrument on the Magellan (Baade) telescope, using the nod-and-shuffle technique. We identify a variety of Type 1 and Type 2 AGN, as well as red galaxies with no emission lines. Our redshift yield is 72% down to i_AB=24, although the yield is >90% for i_AB<22. We expect the completeness to increase as the survey continues. When our survey is complete and additional redshifts from the zCOSMOS project are included, we anticipate ~1100 AGN with redshifts over the entire COSMOS field. Our redshift survey is consistent with an obscured AGN population that peaks at z~0.7, although further work is necessary to disentangle the selection effects.
description: 19 pages, 14 figures. Accepted to ApJS special COSMOS issue. The full electronic version of Table 2 can be found at http://shaihulud.as.arizona.edu/~jtrump/tab2.txt
Graphene integer quantum Hall effect in the ferromagnetic and paramagnetic regimes
Creators: name: Alicea, Jason
name: Fisher, Matthew P. A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Starting from the graphene lattice tight-binding Hamiltonian with an on-site U and long-range Coulomb repulsion, we derive an interacting continuum Dirac theory governing the low-energy behavior of graphene in an applied magnetic field. Initially, we consider a clean graphene system within this effective theory and explore integer quantum Hall ferromagnetism stabilized by exchange from the long-range Coulomb repulsion. We study in detail the ground state and excitations at nu = 0 and nu = \pm 1, taking into account small symmetry-breaking terms that arise from the lattice-scale interactions, and also explore the ground states selected at nu = \pm 3, \pm 4, and \pm 5. We argue that the ferromagnetic regime may not yet be realized in current experimental samples, which at the above filling factors perhaps remain paramagnetic due to strong disorder. In an attempt to access the latter regime where the role of exchange is strongly suppressed by disorder, we apply Hartree theory to study the effects of interactions. Here, we find that Zeeman splitting together with symmetry-breaking interactions can in principle produce integer quantum Hall states in a paramagnetic system at nu = 0, \pm 1 and \pm 4, but not at nu = \pm 3 or \pm 5, consistent with recent experiments in high magnetic fields. We make predictions for the activation energies in these quantum Hall states which will be useful for determining their true origin.
description: 13 pages, 2 figures
Higher-order corrections for $tW$ production at high-energy hadron colliders
Creators: name: Kidonakis, Nikolaos
name: Yamanaka, Nodoka
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss cross sections for $tW$ production in proton-proton collisions at the LHC and at higher-energy colliders with energies of up to 100 TeV. We find that, remarkably, the soft-gluon corrections are numerically dominant even at very high collider energies. We present results with soft-gluon corrections at approximate NNLO and approximate N$^3$LO matched to complete NLO results. These higher-order corrections are large and need to be included for better theoretical accuracy and smaller scale dependence. Total cross sections as well as top-quark and $W$-boson transverse-momentum and rapidity distributions are presented using various recent sets of parton distribution functions.
description: 15 pages, 10 figures; v2 has a lot of new material and several additional plots, and it will appear in JHEP
Self-Organized Network Flows
Creators: name: Helbing, Dirk
name: Siegmeier, Jan
name: Lämmer, Stefan
Publisher: name: arXiv
Year: 2007
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: A model for traffic flow in street networks or material flows in supply networks is presented, that takes into account the conservation of cars or materials and other significant features of traffic flows such as jam formation, spillovers, and load-dependent transportation times. Furthermore, conflicts or coordination problems of intersecting or merging flows are considered as well. Making assumptions regarding the permeability of the intersection as a function of the conflicting flows and the queue lengths, we find self-organized oscillations in the flows similar to the operation of traffic lights.
The effects of artificial diet on gonad size, egg size, egg quality, and larval vitality in green sea urchins, Strongylocentrotus droebachiensis of aquaculture significance
Creators: name: Westman, M. Marja De Jong
Publisher: name: University of British Columbia
Year: 2009

description: Effects of long-term dietary conditioning on gonadal growth, lipid, and moisture content, and on egg size, egg-energy content, larval morphometry, and larval development of the green sea urchin Strongylocentrotus droebachiensis were studied in the laboratory. One algal and seven artificial diets were tested over a nine-month period, coinciding with the urchin’ s annual reproductive cycle. Formulated diets differed in protein level and in the presence or absence of different supplements, such as algal storage carbohydrates (mannitol and algin), cholesterol, and B-carotene. Diets were: 1)10% protein (LO-PRO), 2)10% protein+ mannitol (LO-PRO+M), 3)10% protein+algin (LO-PRO+A), 4) 20% protein (HI-PRO), 5) 20% protein+cholesterol (HI-PRO+C), 6) 20% protein+B-carotene (HI-PRO+B), 7) 20% protein+B-carotene+cholesterol (HI-PRO+C/B), and 8) dried seaweed Nereocystis luetkeana (KELP). Urchins reared on the low-protein diet formulations had significantly smaller gonad indices than urchins conditioned on the highprotein and algal diets. Gonadal lipid and moisture contents varied significantly over time but not among dietary treatments. Significant differences in egg sizes were observed. HI-PRO produced the smallest eggs and HI-PRO+C the largest, while other diet groups produced intermediate-sized eggs. Egg organic-carbon levels also differed significantly with the largest amounts being present in HI-PRO+C/B, and the lowest in LO-PRO and HI-PRO. Larvae cultured from eggs of selected diet groups (LO-PRO, HI-PRO, HI PRO+B, HI-PRO+C/B, and KELP) showed significant differences in morphometry and in rates of development. HI-PRO+B and HI-PRO+C/B were the first to reach the feeding pluteal stage at 3 days and the 2-arm pluteus at 5-6 days. The feeding pluteal stage was attained by LO-PRO and HI-PRO at 4 days and the 2-armed larvae at 7-8 days. Larval development times for LO-PRO, HI-PRO, and HI-PRO+C/B were comparable by the 4-arm stage and remained so throughout development. HI-PRO+B larvae consistently had the shortest development times, reaching the fully-formed 8-arm larval stage 3 days earlier than larvae from other diet groups. HI-PRO+B larvae also had the highest rate of metamorphosis success. They showed significantly higher diary band/body-length ratios throughout all developmental stages, indicating greater larval feeding effectiveness and suggesting that this was the key to their overall success. All larvae arising from adults fed the artificial diets were competent; however, larvae from adults fed KELP showed severe abnormalities and subsequent early mortality. With regard to an aquaculture program, I conclude that HI-PRO+B is the best of the diets tested, in that it supported high gonathi growth for the roe market, and produced healthy broodstock with resultant vigorous larvae.
Direct Photon Production in p+p and d+Au Collisions Measured with the PHENIX Experiment
Creators: name: Peressounko, D.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Direct photon yield measured in p+p and d+Au collisions at \sqrt{s} = 200 GeV with the PHENIX experiment is presented and compared to pQCD predictions. In the case of p+p collisions both the inclusive and isolated direct photon production cross-sections are measured. Relative contribution of isolated direct photons is somewhat below but still agree within errors with pQCD predictions. In the case of d+Au collisions no modifications due to presence of cold matter are found within errors.
description: 4 pages, 5 figures, proceedings of the Hard Probes 2006 conference, Asilomar, Pacific Grove, California
Susceptibilities and the Phase Structure of an Effective Chiral Model with Polyakov Loops
Creators: name: Sasaki, C.
name: Friman, B.
name: Redlich, K.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: In the Nambu--Jona-Lasinio model with Polyakov loops, we explore the relation between the deconfinement and chiral phase transitions within the mean-field approximation. We focus on the phase structure of the model and study the susceptibilities associated with corresponding order parameters.
description: 6 pages, 2 figures, contribution to the proceedings of the 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (QM2006), November 14-20 2006, Shanghai, China
Dark matter clustering: a simple renormalization group approach
Creators: name: McDonald, Patrick
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: I compute a renormalization group (RG) improvement to the standard beyond-linear-order Eulerian perturbation theory (PT) calculation of the power spectrum of large-scale density fluctuations in the Universe. At z=0, for a power spectrum matching current observations, lowest order RGPT appears to be as accurate as one can test using existing numerical simulation-calibrated fitting formulas out to at least k~=0.3 h/Mpc; although inaccuracy is guaranteed at some level by approximations in the calculation (which can be improved in the future). In contrast, standard PT breaks down virtually as soon as beyond-linear corrections become non-negligible, on scales even larger than k=0.1 h/Mpc. This extension in range of validity could substantially enhance the usefulness of PT for interpreting baryonic acoustic oscillation surveys aimed at probing dark energy, for example. I show that the predicted power spectrum converges at high k to a power law with index given by the fixed-point solution of the RG equation. I discuss many possible future directions for this line of work. The basic calculation of this paper should be easily understandable without any prior knowledge of RG methods, while a rich background of mathematical physics literature exists for the interested reader.
description: much expanded explanation of basic calculation
Cold fronts in cool core clusters
Creators: name: Ghizzardi, S.
name: Molendi, S.
name: Rossetti, M.
name: Leccardi, A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Cold fronts have been detected both in merging and in cool core clusters, where little or no sign of a merging event is present. A systematic search of sharp surface brightness discontinuities performed on a sample of 62 galaxy clusters observed with XMM-Newton shows that cold fronts are a common feature in galaxy clusters. Indeed most (if not all) of the nearby clusters (z < 0.04) host a cold front. Understanding the origin and the nature of a such frequent phenomenon is clearly important. To gain insight on the nature of cold fronts in cool core clusters we have undertaken a systematic study of all contact discontinuities detected in our sample, measuring surface brightness, temperature and when possible abundance profiles across the fronts. We measure the Mach numbers for the cold fronts finding values which range from 0.2 to 0.9; we also detect a discontinuities in the metal profile of some clusters.
description: 6 pages, 3 figures, for proceedings of "Heating vs. Cooling in Galaxies and Clusters of Galaxies," eds H. Boehringer, P. Schuecker, G. W. Pratt & A. Finoguenov, in Springer-Verlag series "ESO Astrophysics Symposia."
Application of density dependent parametrization models to asymmetric nuclear matter
Creators: name: Liu, B.
name: Di Toro, M.
name: Greco, V.
name: Shen, C. W.
name: Zhao, E. G.
name: Sun, B. X.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Density dependent parametrization models of the nucleon-meson effective couplings, including the isovector scalar δ-field, are applied to asymmetric nuclear matter. The nuclear equation of state and the neutron star properties are studied in an effective Lagrangian density approach, using the relativistic mean field hadron theory. It is known that the introduction of a δ-meson in the constant coupling scheme leads to an increase of the symmetry energy at high density and so to larger neutron star masses, in a pure nucleon-lepton scheme. We use here a more microscopic density dependent model of the nucleon-meson couplings to study the properties of neutron star matter and to re-examine the δ-field effects in asymmetric nuclear matter. Our calculations show that, due to the increase of the effective δcoupling at high density, with density dependent couplings the neutron star masses in fact can be even reduced.
description: 5 pages, 4 figures
Θεσμικοί και μη θεσμικοί παράγοντες. Η περίπτωση της Βασίλισσας Φρειδερίκης
Creators: name: Σκουμπόπουλος Κωνσταντίνος Αντωνίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Βασίλισσα Φρειδερίκη
Μοναρχία
Παρέμβαση
Queen Frederica
Monarchy
Intervention

description: Σκοπός της παρούσας εργασίας είναι να εξετάσει την παρεμβατικότητα της βασίλισσάς Φρειδερίκης της Ελλάδας στο πολιτικό σκηνικό. Στην εργασία παρουσιάζεται η εξωθεσμική ως επί το πλείστον παρεμβατικότητα της βασίλισσας Φρειδερίκης σε μια σειρά τομέων. Αρχικά παρατίθεται η ενασχόληση της με το εσωτερικό πολιτικό σκηνικό και την διαμόρφωσή του για την ανάδειξη κυβερνήσεων και αρεστών προσώπων σε αυτή και γενικότερα στο Θρόνο. Εν συνεχεία παρουσιάζονται οι βασικές κινήσεις της βασίλισσας Φρειδερίκης στα ζητήματα εξωτερικής πολιτικής σε μια προσπάθεια της να διαμορφώσει τις διεθνείς σχέσεις της Ελλάδας με βάση και τις συνθήκες της εποχής. Τέλος γίνεται αναφορά στον τομέα της κοινωνικής πολιτικής με τον οποίο ασχολήθηκε εκτενώς η βασίλισσα Φρειδερίκη και ως στόχο είχε την ενίσχυση της παροχής κοινωνικών υπηρεσιών προς τα ασθενέστερα κοινωνικά στρώματα αλλά και την ισχυροποίηση του Στέμματος και του αστικού Δυτικόφιλου καθεστώτος στην Ελλάδα.
description: The aim of this postgraduate thesis is to examine the intermeddling of Queen Frederica of Greece on the political scene. This work presents in large part the non-institutional intervention of Queen Frederica in a number of areas. Initially, it is concerned with the internal political scene and its formation for the emergence of governments and the selection of key players sympathetic to the Crown. The paper goes on to present the Queen’s skillful maneuvering on foreign policy issues in an effort to shape the international relations of Greece, based on the conditions of the time. Finally, a reference is made to the social policies with which Queen Frederica had been extensively involved. Her objective was to strengthen the provision of social services in the weaker social classes and to try to consolidate the Crown and the pro-western regime in Greece.
The Evolving Luminosity Function of Red Galaxies
Creators: name: Brown, Michael J. I.
name: Dey, Arjun
name: Jannuzi, Buell T.
name: Brand, Kate
name: Benson, Andrew J.
name: Brodwin, Mark
name: Croton, Darren J.
name: Eisenhardt, Peter R.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We trace the assembly history of red galaxies since z=1, by measuring their evolving space density with the B-band luminosity function. Our sample of 39599 red galaxies, selected from 6.96 square degrees of imaging from the NOAO Deep Wide-Field and Spitzer IRAC Shallow surveys, is an order of magnitude larger, in size and volume, than comparable samples in the literature. We measure a higher space density of z=0.9 red galaxies than some of the recent literature, in part because we account for the faint yet significant galaxy flux which falls outside of our photometric aperture. The B-band luminosity density of red galaxies, which effectively measures the evolution of ~L* galaxies, increases by only 36 percent from z=0 to z=1. If red galaxy stellar populations have faded by 1.24 B-band magnitudes since z=1, the stellar mass contained within the red galaxy population has roughly doubled over the past 8 Gyr. This is consistent with star-forming galaxies being transformed into ~L* red galaxies after a decline in their star formation rates. In contrast, the evolution of 4L* red galaxies differs only slightly from a model with negligible star formation and no galaxy mergers since z=1. If this model approximates the luminosity evolution of red galaxy stellar populations, then 80 percent of the stellar mass contained within today's 4L* red galaxies was already in place at z=0.7. While red galaxy mergers have been observed, such mergers do not produce rapid growth of 4L* red galaxy stellar masses between z=1 and the present day.
description: Accepted for publication in the ApJ. 30 pages, 18 figures. (Several typos corrected and slight change to Figure 8.)
Electroweak monopoles and magnetic dumbbells in grand unified theories
Creators: name: Lazarides, George
name: Shafi, Qaisar
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We use the $SU(5)$ model to show the presence in grand unified theories of an electroweak monopole and a magnetic dumbbell ("meson") made up of a monopole-antimonopole pair connected by a $Z$-magnetic flux tube. The monopole is associated with the spontaneous breaking of the weak $SU(2)_L$ gauge symmetry by the induced vacuum expectation value of a heavy scalar $SU(2)_L$ triplet with zero weak hypercharge contained in the adjoint Higgs 24-plet. This monopole carries a Coulomb magnetic charge of $(3/4) (2π/e)$ as well as $Z$-magnetic charge, where $2π/e$ denotes the unit Dirac magnetic charge. Its total magnetic charge is $\sqrt{3/8}(4π/e)$, which is in agreement with the Dirac quantization condition. The monopole weighs about 700 GeV, but because of the attached $Z$-magnetic tube it exists, together with the antimonopole, in a magnetic dumbbell configuration whose mass is expected to lie in the TeV range. The presence of these topological structures in $SU(5)$ and $SO(10)$ and in their supersymmetric extensions provides an exciting new avenue for testing these theories in high-energy colliders.
description: 5 pages, version published in Phys. Rev. D
A Data Driven Analysis of Energy Deposition in Solar Active Regions
Creators: name: Κούκρας, Αλέξανδρος Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Ηλιακές ενεργές περιοχές
Νανο-εκλάμψεις
Θέρμανση στεμματικών βρόγχων
Solar active regions
Nanoflares
Coronal heating

description: The goal of this project is to study the connection of the magnetic discontinuities the current fragmentation and the energy deposition in the extrapolated magnetic field of a solar active region. In order to reconstruct the coronal magnetic field above an active region we use a linear force-free extrapolation method. Next, we calculate the distribution of the discontinuities and examine where we have a power law like slop. In combination with a clustering algorithm, which utilize a partitional hard clustering method, we locate the site of energy deposition along the length of each magnetic loop. In this framework, we express these sites of energy release as nanoflares and by using a 0MHD (Magnetohydrodynamic, EBTEL) we are able to calculate the temperature profile of each loop. Having taken into account the existence of anomalous resistivity, due to current instabilities, we are able to produce a range of loop temperatures depending on the selected value for the resistivity. Finally, we compare our results with typical values of the temperature in the solar corona, in order to examine if this mechanism of energy deposition is able to produce realistic results
description: Σκοπός αυτής της εργασίας είναι η μελέτη της συσχέτισης ανάμεσα στις μαγνητικές ασυνέχειες (magnetic discontinuities) του κατακερματισμού των ρευμάτων και τον τρόπο που εναποτίθενται ενέργεια στο extrapolated μαγνητικό πεδίο μιας ενεργής περιοχής του Ήλιου (solar active region). Για ανακαταστευάσουμε το μαγνητικό πεδίο του στέμματος πάνω από μια ενεργή περιοχή χρησιμοποιούμε linear force-free extrapolation. Στην συνέχεια βρίσκουμε την κατανομή των ρευμάτων και υπολογίζουμε που έχουμε κατανομές νόμου δύναμης. Σε συνδυασμό με την εφορμογή ενός clustering αλγορίθμου (partitional hard clustering) εντοπίζουμε τα σημεία εναπόθεσης ενέργειας κατα μήκος κάθε μαγνητικού βρόγχου. Εκφrάζοντας αυτά τα ‘θερμά σημεία’ ως ‘νανο-εκλάμψεις’ και χρησιμοποιώντας ένα 0MHD (Μαγνητοϋδροδυναμικό, EBTEL) μοντέλο, έχοντας λάβει υπόψη την εμφάνιση της anomalous resistivity λόγω των ασταθειών των ρευμάτων (current instabilities), μπορούμε να υπολογίσουμε το προφίλ της θερμοκρασίας κάθε βρόγχου. Τέλος, έχοντας την θερμοκρασία που φτάνουν οι στεμματικοί βρόγχοι εξετάζουμε αν οι τιμές αυτές είναι συγκρίσιμες με τις τυπικές τιμές θερμοκρασίας στο ηλιακό στέμμα, ώστε να δούμε αν αυτός ο μηχανισμός εναπόθεσης ενέργειας είναι ικανός να παράξει ρεαλιστικά αποτελέσματα.
Inflationary cosmology and the late-time accelerated expansion of the universe in non-minimal Yang-Mills-$F(R)$ gravity and non-minimal vector-$F(R)$ gravity
Creators: name: Bamba, Kazuharu
name: Nojiri, Shin'ichi
name: Odintsov, Sergei D.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study inflationary cosmology and the late-time accelerated expansion of the universe in non-minimal Yang-Mills (YM) theory, in which the YM field couples to a function of the scalar curvature. It is shown that power-law inflation can be realized due to the non-minimal YM field-gravitational coupling which maybe caused by quantum corrections. Moreover, it is demonstrated that both inflation and the late-time accelerated expansion of the universe can be realized in a modified YM-$F(R)$ gravity which is consistent with solar system tests. Furthermore, it is shown that this result can be realized also in a non-minimal vector-$F(R)$ gravity. In addition, we consider the duality of the non-minimal electromagnetic theory and that of the non-minimal YM theory, and also discuss the cosmological reconstruction of the YM theory.
description: 21 pages, no figure, shortened version, accepted in PRD, misprints corrected
Tailoring Infrared Absorption and Thermal Emission with Ultrathin-film Interferences in Epsilon-Near-Zero Media
Creators: name: Johns, Ben
name: Chattopadhyay, Shashwata
name: Mitra, Joy
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Engineering nanophotonic mode dispersions in ultrathin, planar structures enables significant control over infrared perfect absorption (PA) and thermal emission characteristics. Here, using simulations, the wavelength and angular ranges over which ultrathin, low loss, epsilon-near-zero (ENZ) films on a reflecting surface most efficiently absorb and re-radiate are identified, and the design parameters that tailor the ENZ mode dispersion within these limits are investigated. While the absorption is spectrally limited to wavelengths where the refractive index ($n$) lies below unity, the angular limits are determined by the ENZ material dispersion in this range. A model of ultrathin-film interference is developed to provide physical insight into the absorption resonances in this regime, occurring well below the conventional quarter-wavelength thickness limit. Driven by non-trivial phase shifts incurred on reflection at the $n<1$ surface, these resonant interferences are shown to be universal wave phenomena in planar structures having appropriate index contrast, extending beyond ENZ materials. Selective choice of material, film thickness and loss allows fine-tailoring the mode dispersions, enabling wide variation in spectral range ($ \sim 0.1 - 1.0 μm$) and precise directional control of spectrally and angularly narrow-band PA and thermal radiation, paving the way towards efficient ENZ-based infrared optical and thermal coatings.
description: Main & supplementary; Added analysis and 1 figure in Main
Shifted Schur process and asymptotics of large random strict plane partitions
Creators: name: Vuletić, Mirjana
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: Combinatorics (math.CO)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: In this paper we define the shifted Schur process as a measure on sequences of strict partitions. This process is a generalization of the shifted Schur measure introduced in [TW] and [Mat] and is a shifted version of the Schur process introduced in [OR]. We prove that the shifted Schur process defines a Pfaffian point process. We further apply this fact to compute the bulk scaling limit of the correlation functions for a measure on strict plane partitions which is an analog of the uniform measure on ordinary plane partitions. As a byproduct, we obtain a shifted analog of the famous MacMahon's formula.
description: AMSTex, 48 pages, 12 figures
The archival concept of competence: a case study of the federal administration of agriculture in Canada, 1867-1989
Creators: name: Stewart, Kelly Anne
Publisher: name: University of British Columbia
Year: 2009

description: This thesis sets out to explain how spheres of responsibility or competences are assigned in the administration of government functions in order to assess the ways in which archivists can come to terms with increasingly rapid rates of administrative change in the performance of their work. It examines statutes and government publications to present a picture of the evolution of the competence of agencies of the government of Canada given responsibility for carrying out activities in administration of the function of agriculture. It is found that knowledge of the assignment of functional responsibility is essential to a number of archival tasks. It is vital to know all the bodies participating in carrying out the function when appraising records. A vital part of identifying the external structure of a fonds lies in determining the competence of the agencies creating records in it, and this knowledge must be effectively communicated in archival description. Finally, the concepts of function, competence, and activity, if clearly understood, can guide the development of vocabularies to assist users of archives to find loci of administrative action relevant to searches they are undertaking. Accumulating information about the functions, competences, and activities of organizations and keeping it current can serve many purposes in the administration of records during the entire life cycle. Organizations need this information to control and provide access to records for administrative purposes and to facilitate secondary access under freedom of information and privacy legislation or for historical research purposes. The method of analyzing how functional activity employed in this study can be used for all government organizations in Canada.
Imprint of SUSY in radiative B-meson decays
Creators: name: Eberl, H.
name: Hidaka, K.
name: Ginina, E.
name: Ishikawa, A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study supersymmetric (SUSY) effects on $C_7(μ_b)$ and $C'_7(μ_b)$ which are the Wilson coefficients (WCs) for $b \to s γ$ at b-quark mass scale $μ_b$ and are closely related to radiative $B$-meson decays. The SUSY-loop contributions to $C_7(μ_b)$ and $C'_7(μ_b)$ are calculated at leading order (LO) in the Minimal Supersymmetric Standard Model (MSSM) with general quark-flavour violation (QFV). For the first time we perform a systematic MSSM parameter scan for the WCs $C_7(μ_b)$ and $C'_7(μ_b)$ respecting all the relevant constraints, i.e. the theoretical constraints from vacuum stability conditions and the experimental constraints, such as those from $K$- and $B$-meson data and electroweak precision data, as well as recent limits on SUSY particle masses and the 125 GeV Higgs boson data from LHC experiments. From the parameter scan we find the following: (1) The MSSM contribution to Re($C_7(μ_b)$) can be as large as $\sim \pm 0.05$, which could correspond to about 3$σ$ significance of New Physics (NP) signal in the future LHCb and Belle II experiments. (2) The MSSM contribution to Re($C'_7(μ_b)$) can be as large as $\sim -0.08$, which could correspond to about 4$σ$ significance of NP signal in the future LHCb and Belle II experiments. (3) These large MSSM contributions to the WCs are mainly due to (i) large scharm-stop mixing and large scharm/stop involved trilinear couplings, (ii) large sstrange-sbottom mixing and large sstrange-sbottom involved trilinear couplings and (iii) large bottom Yukawa coupling $Y_b$ for large $\tanβ$ and large top Yukawa coupling $Y_t$. In case such large NP contributions to the WCs are really observed in the future experiments at Belle II and LHCb Upgrade, this could be the imprint of QFV SUSY (the MSSM with general QFV).
description: 34 pages, 13 figures, a few comments added, final result unchanged
A class of superintegrable systems of Calogero type
Creators: name: Smirnov, Roman G.
name: Winternitz, Pavel
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mathematical Physics (math-ph)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences
subject: 37J35, 53C05

description: We show that the three body Calogero model with inverse square potentials can be interpreted as a maximally superintegrable and multiseparable system in Euclidean three-space. As such it is a special case of a family of systems involving one arbitrary function of one variable.
description: Extended references, more content has been added
Αξιολόγηση της αποτελεσματικότητας της χρήσης μηχανοκίνητων εργαλείων νικελίου-τιτανίου από τεταρτοετείς φοιτητές του Τμήματος Οδοντιατρικής ΑΠΘ- Προοπτική κλινική μελέτη
Creators: name: Τζίμα, Ζωή-Δέσποινα Λεωνίδα
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Hyflex CM
διεπεμβατικά συμβάματα
προπτυχιακή οδοντιατρική κλινική
procedural errors
undergraduate dental clinic

description: Ο σκοπός της παρούσας προοπτικής κλινικής μελέτης ήταν διττός. Στο πρώτο σκέλος έγινε διερεύνηση της αποτελεσματικότητας των Hyflex CM (Coltene/Whaledent, Altstätten Switzerland) περιστροφικών μικροεργαλείων καταγράφοντας τη συχνότητα διεπεμβατικών συμβαμάτων, και την αξιολόγηση της ποιότητας της έμφραξης έπειτα από ακτινογραφική παρατήρηση. Στο δεύτερο σκέλος διενεργήθηκε μία μελέτη αξιολόγησης της μηχανοκίνητης εμπειρίας με τη χρήση ερωτηματολογίου. Κατά τη διάρκεια τριών ακαδημαϊκών ετών (2014-2017) εκατόν δεκαοκτώ (118) τεταρτοετείς προπτυχιακοί φοιτητές χωρίς προηγούμενη μηχανοκίνητη εμπειρία, ολοκλήρωσαν μια ενδοδοντική θεραπεία σε ένα γομφίο. Με το πέρας της θεραπείας κάθε συμμετέχοντας συμπλήρωσε ένα ερωτηματολόγιο κλειστού τύπου. Τα ποσοστά θραύσης μικροεργαλείου, ακρορριζικής διάτρησης, ριζικής διάτρησης, ευθειασμού και βάθρων ήταν 0.8%, 4.4%, 2.3%, 5.5% και 29% αντίστοιχα, οι ριζικοί σωλήνες με αποδεκτή έμφραξη έφτασαν το 68.4%, ενώ το ποσοστό των υπερεμφραγμένων και υπεμφραγμένων ριζικών σωλήνων βρέθηκε να είναι 8.6% και 16.2% αντίστοιχα. Το ποσοστό ανταπόκρισης του ερωτηματολογίου ήταν 94.9% με το 35% των συμμετεχόντων να μη συναντά δυσκολία. Η συχνότητα των συμβαμάτων ήταν χαμηλή, η έμφραξη διατηρήθηκε σε καλό τεχνικό επίπεδο ενώ τα μηχανοκίνητα μικροεργαλεία χαρακτηρίστηκαν ως εύχρηστα
description: The aim of the present study was to investigate the incidence of procedural errors with the use of a nickel-titanium rotary system (Hyflex CM, Coltene/Whaledent, Altstätten Switzerland) and evaluate the technical quality of root fillings in an undergraduate dental clinic between 2014 and 2017. One hundred and eighteen (118) undergraduate students with no previous experience in rotary instrumentation performed a root canal treatment on a patient’s molar. After the root canal treatment was performed they completed a questionnaire. The incidence of instrument separation, apical perforation, root perforation, straightening and ledges was 0.8%, 4.4%, 2.3%, 5.5% and 29% respectively. The frequency of root canals with an ‘acceptable’ filling was 68.4%. The response rate was high (94.9%), while 35% of the participants encountered no difficulty in using rotary instrumentation. The incidence of procedural errors was considerably low and the technical quality of the filled root canals was superior to that of similar studies
Cohesion and excitations of diamond-structure silicon by quantum Monte Carlo: Benchmarks and control of systematic biases
Creators: name: Annaberdiyev, Abdulgani
name: Wang, Guangming
name: Melton, Cody A.
name: Bennett, M. Chandler
name: Mitas, Lubos
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We have carried out quantum Monte Carlo (QMC) calculations of silicon crystal focusing on the accuracy and systematic biases that affect the electronic structure characteristics. The results show that 64 and 216 atom supercells provide an excellent consistency for extrapolated energies per atom in the thermodynamic limit for ground, excited, and ionized states. We have calculated the ground state cohesion energy with both $\textit{systematic and statistical errors}$ below $\approx$0.05 eV. The ground state exhibits a fixed-node error of only $1.3(2)\%$ of the correlation energy, suggesting an unusually high accuracy of the corresponding single-reference trial wave function. We obtain a very good agreement between optical and quasiparticle gaps that affirms the marginal impact of excitonic effects. Our most accurate results for band gaps differ from the experiments by about 0.2 eV. This difference is assigned to a combination of residual finite-size and fixed-node errors. We have estimated the crystal Fermi level referenced to vacuum that enabled us to calculate the edges of valence and conduction bands in agreement with experiments.
description: Peer-reviewed version
Πολιτικοί Σχεδιασμοί και Προσδοκώμενα Αποτελέσματα από τη Σύνδεση της Ελλάδος με την ΕΟΚ (1958-1967)
Creators: name: Κοτσιανού, Γαρυφαλιά Νικολάου
Publisher: name: Aristotle University of Thessaloniki
Year: 2018
Subjects: Συμφωνία Σύνδεσης
ΕΟΚ
Ευρωπαϊκή Οικονομική Κοινότητα
Association Agreement
EEC
European Economic Community

description: Στις 9 Ιουλίου 1961 η Ελλάδα υπέγραψε Συμφωνία Σύνδεσης με την Ευρωπαϊκή Οικονομική Κοινότητα με σκοπό την ενσωμάτωση και μακροπρόθεσμα, την ένταξη της στην Κοινότητα. Η προσπάθεια της χώρας για πολιτική και οικονομική ενοποίηση με την ΕΟΚ αποτέλεσε καθοριστικό γνώμονα στη διαμόρφωση της πολιτικής σε εσωτερικό αλλά και σε διεθνές επίπεδο. Σκοπός της εργασίας είναι η μελέτη των πολιτικών σχεδιασμών και των προσδοκώμενων αποτελεσμάτων από τη Σύνδεση της Ελλάδας με την Κοινότητα. Ως εκ τούτου, θα εξετασθεί η οικονομική και πολιτική προπαρασκευή που πραγματοποίησε η Ελλάδα προκειμένου να αντεπεξέλθει στα αιτήματα της ΕΟΚ. Επιπλέον θα αναζητηθούν οι προσδοκίες που είχε η χώρα από τη Συμφωνία Σύνδεσης και τελικά, ο βαθμός στον οποίο αυτές εκπληρώθηκαν
description: On July 9th, 1961 Greece signed the Association Agreement with the European Economic Community aiming at the integration and in the long run, the accession to the EEC. The country's endeavor for political and economic integration was a decisive factor in its policy making. This thesis aims at the analysis of the political planning and the expected results of the Association Agreement of Greece with the European Economic Community. Therefore, the thesis' primary aim is the study of the economic and political planning of Greece in order to meet the demands of the EEC as well as the study of Greece's expectations of the Association Agreement and the extent to which these expectations were fulfilled
Merger Transitions in Brane--Black-Hole Systems: Criticality, Scaling, and Self-Similarity
Creators: name: Frolov, Valeri P.
Publisher: name: arXiv
Year: 2006
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We propose a toy model for study merger transitions in a curved spaceime with an arbitrary number of dimensions. This model includes a bulk N-dimensional static spherically symmetric black hole and a test D-dimensional brane interacting with the black hole. The brane is asymptotically flat and allows O(D-1) group of symmetry. Such a brane--black-hole (BBH) system has two different phases. The first one is formed by solutions describing a brane crossing the horizon of the bulk black hole. In this case the internal induced geometry of the brane describes D-dimensional black hole. The other phase consists of solutions for branes which do not intersect the horizon and the induced geometry does not have a horizon. We study a critical solution at the threshold of the brane-black-hole formation, and the solutions which are close to it. In particular, we demonstrate, that there exists a striking similarity of the merger transition, during which the phase of the BBH-system is changed, both with the Choptuik critical collapse and with the merger transitions in the higher dimensional caged black-hole--black-string system.
description: 9 pages 2 figures; additional remarks and references are added at Section IX "Discussion"
Catastrophic Cooling in Superwinds. II. Exploring the Parameter Space
Creators: name: Danehkar, Ashkbiz
name: Oey, M. S.
name: Gray, William J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Superwinds and superbubbles driven by mechanical feedback from super star clusters (SSCs) are common features in many star-forming galaxies. While the adiabatic fluid model can well describe the dynamics of superwinds, several observations of starburst galaxies revealed the presence of compact regions with suppressed superwinds and strongly radiative cooling, i.e., catastrophic cooling. In the present study, we employ the non-equilibrium atomic chemistry and cooling package MAIHEM, built on the FLASH hydrodynamics code, to generate a grid of models investigating the dependence of cooling modes on the metallicity, SSC outflow parameters, and ambient density. While gas metallicity plays a substantial role, catastrophic cooling is more sensitive to high mass-loading and reduced kinetic heating efficiency. Our hydrodynamic simulations indicate that the presence of a hot superbubble does not necessarily imply an adiabatic outflow, and vice versa. Using CLOUDY photoionization models, we predict UV and optical line emission for both adiabatic and catastrophic cooling outflows, for radiation-bounded and partially density-bounded models. Although the line ratios predicted by our radiation-bounded models agree well with observations of star-forming galaxies, they do not provide diagnostics that unambiguously distinguish the parameter space of catastrophically cooling flows. Comparison with observations suggests the possibility of minor density bounding, non-equilibrium ionization, and/or observational bias toward the central outflow regions.
description: 25 pages, 13 figures (inc. 2 interactive figs, 1 interactive animation), 1 Table (inc. 6 MRT), published by ApJ, supplementary data (interactive figures, videos, machine readable tables) available on https://superwinds.astro.lsa.umich.edu/ and archived on https://doi.org/10.5281/zenodo.4989577
Classical Lie algebras and Drinfeld doubles
Creators: name: Ballesteros, A.
name: Celeghini, E.
name: del Olmo, M. A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Group Theory (math.GR)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 81R50; 81R40; 17B37

description: The Drinfeld double structure underlying the Cartan series An, Bn, Cn, Dn of simple Lie algebras is discussed. This structure is determined by two disjoint solvable subalgebras matched by a pairing. For the two nilpotent positive and negative root subalgebras the pairing is natural and in the Cartan subalgebra is defined with the help of a central extension of the algebra. A new completely determined basis is found from the compatibility conditions in the double and a different perspective for quantization is presented. Other related Drinfeld doubles on C are also considered.
description: 11 pages. submitted for publication to J. Physics A