cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
On the magnetic nanostructure of a Co-Cu alloy processed by high-pressure torsion
Creators: name: Stückler, Martin
name: Teichert, Christian
name: Matković, Aleksandar
name: Krenn, Heinz
name: Weissitsch, Lukas
name: Wurster, Stefan
name: Pippan, Reinhard
name: Bachmaier, Andrea
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In this study, a preparation route of Co-Cu alloys with soft magnetic properties by high-pressure torsion deformation is introduced. Nanocrystalline, supersaturated single-phase microstructures are obtained after deformation of Co-Cu alloys, which are prepared from an initial powder mixture with Co-contents above 70 wt.%. Isochronal annealing treatments up to 400°C further reveal a remarkable microstructural stability. Only at 600°C, the supersaturated phase decomposes into two fcc-phases. The coercivity, measured by SQUID as a function of annealing temperature, remains significantly below the value for bulk-Co in all states investigated. In order to understand the measured magnetic properties in detail, a quantitative analysis of the magnetic microstructure is carried out by magnetic force microscopy and correlated to the observed changes in coercivity. Our results show that the rising coercivity can be explained by a magnetic hardening effect occurring in context with spinodal decomposition.
Computational methods for the shape from shading problem
Creators: name: Carter, Paul M.
Publisher: name: University of British Columbia
Year: 2008

description: The aim of this thesis is to explore computational methods for the shape from shading problem as formulated through the image irradiance equation. We seek to develop robust, efficient methods and test our algorithms on synthetic images ranging from simple smooth surfaces to complex digital terrain model data. We consider three different approaches. The first approach revisits the method of characteristic strips with a view to using more stable integration schemes than had been used in earlier works. Stable schemes, coupled with projections onto the image irradiance equation are used. Although the effects of noise are thereby reduced, the solution is still deemed unsatisfactory even for very simple surfaces. The second approach considers Horn's variational technique as a basis for producing a fast solver. We devise a discretization scheme coupled with a special continuation-multi grid method for this formulation. We also allow for multiple image data and explicit knowledge of the location of discontinuities in surface height and orientation. Given multiple image data, we obtain excellent results even in the presence of discontinuities. The third approach examines a class of solution techniques based on fluid flow which are new to the shape from shading literature. This formulation is ill-posed in general, so we propose a regularization of the problem. We observe that the algorithm is prone to producing spurious results. Analysis shows that these are due to the non-random accumulation of errors in the computed solution. Of the three approaches considered, the variational method yields the most promising results. Efficient, good quality reconstructions are obtained, especially when data from more than one image are available.
Absolute instability in shock-containing jets
Creators: name: Nogueira, Petrônio A. S.
name: Jordan, Peter
name: Jaunet, Vincent
name: Cavalieri, André V. G.
name: Towne, Aaron
name: Edgington-Mitchell, Daniel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We present an analysis of the linear stability characteristics of shock-containing jets. The flow is linearised around a spatially periodic mean, which acts as a surrogate for a mean flow with a shock-cell structure, leading to a set of partial differential equations with periodic coefficients in space. Disturbances are written using the Floquet ansatz and Fourier modes in the streamwise direction, leading to an eigenvalue problem for the Floquet exponent. The characteristics of the solution are directly compared to the locally parallel case, and some of the features are similar. The inclusion of periodicity induces minor changes in the growth rate and phase velocity of the relevant modes for small shock amplitudes. On the other hand, the eigenfunctions are now subject to modulation related to the periodicity of the flow. Analysis of the spatio-temporal growth rates led to the identification of a saddle point between the Kelvin-Helmholtz mode and the guided jet mode, characterising an absolute instability mechanism. Frequencies and mode shapes related to the saddle points for two conditions (associated with axisymmetric and helical modes) are compared with screech frequencies and the most energetic coherent structures of screeching jets, resulting in a good agreement for both. The analysis shows that a periodic shock-cell structure has an impulse response that grows upstream, leading to oscillator behaviour. The results suggest that screech can occur in the absence of a nozzle, and that the upstream reflection condition is not essential for screech frequency selection. Connections to previous models are also discussed.
description: Submitted to the Journal of Fluid Mechanics
Lamellar Phases in Nonuniform Electric Fields: Breaking the In-Plane Rotation Symmetry and the Role of Dielectric Constant Mismatch
Creators: name: Tsori, Yoav
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We consider orientational transitions of lamellar phases under the influence of a spatially nonuniform electric field. The transition between parallel and perpendicular lamellar stackings with respect to the substrate is investigated as a function of the system parameters. The dielectrophoretic energy and the energy penalty for having dielectric interfaces perpendicular to the field's direction are identified as linear and quadratic terms in a free energy expansion in the dielectric constant mismatch. We find that if the dielectric constant mismatch $Δ\eps$ is smaller than some critical value $Δ\eps_c$, parallel lamellar stacking will be realized, no matter how large the voltage difference between electrodes is. At $Δ\eps>Δ\eps_c$, perpendicular stacking will appear if the voltage is high enough. Nonuniform fields remove the in-plane degeneracy present in the more common uniform fields. We therefore calculate the energy of grains of different orientations. The torque acting on the grains leads to the preference of only one orientation. The results have direct implications to block copolymer orientation and to surface patterning on the nanometer scale.
description: 5 pages, 7 figures
Μελέτη και χαρακτηρισμός υλικών και κατάσταση φθοράς των λίθων του Αρχαιολογικού χώρου της Πέλλας
Creators: name: Γκράβα, Ειρήνη Παναγιώτη
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Αρχαιολογικός χώρος της Πέλλας
Λίθος
Κατάσταση φθοράς
Archaeological area of Pella
Stone
Decay state

description: Σκοπός της διπλωματικής εργασίας ήταν η μελέτη των μνημείων του αρχαιολογικού χώρου της Πέλλας και συγκεκριμένα ο χαρακτηρισμός και η διάγνωση της φθοράς του λίθου ως δομικό υλικό των υπαρχόντων μνημείων. Αρχικά δίνονται κάποια ιστορικά στοιχεία του αρχαιολογικού χώρου της Πέλλας. Στη συνέχεια αναφέρονται οι κύριοι μηχανισμοί διάβρωσης των δομικών στοιχείων καθώς και το περιβάλλον έκθεσης των μνημείων συναρτήσει με τους παράγοντες επιτάχυνσης της υποβάθμισης και διάβρωσης τους. Εν συνεχεία περιγράφεται η παρούσα κατάστασης των μνημείων κι έπειτα η μεθοδολογία χαρακτηρισμού των υλικών και της κατάστασης φθοράς. Εν κατακλείδι παρουσιάζεται η δειγματοληψία και η μεθοδολογία της προκαταρκτικής εργαστηριακής έρευνας.
description: The purpose of the dissertation was the study of the monuments of the archeological site of Pella and specifically the characterization and the diagnosis of the deterioration of the stone as a structural material of the existing monuments. Initially, some historical data of the archeological site of Pella are given. The following are the main mechanisms for corrosion of structural elements as well as the exhibition environment of the monuments in relation to the factors that accelerate their degradation and corrosion. This is followed by a description of the current state of the monuments and then the methodology for characterizing the materials and the state of wear. In conclusion, the sampling and methodology of the preliminary laboratory research is presented.
description: Σε συνεργασία με: Ανώτατη Εκκλησιαστική Ακαδημία Θεσσαλονίκης
Vacuum Birefringence as a Probe of Planck Scale Noncommutativity
Creators: name: Abel, Steven A.
name: Jaeckel, Joerg
name: Khoze, Valentin V.
name: Ringwald, Andreas
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Because of ultraviolet/infrared (UV/IR) mixing, the low energy physics of noncommutative gauge theories in the Moyal-Weyl approach seems to depend crucially on the details of the ultraviolet completion. However, motivated by recent string theory analyses, we argue that their phenomenology with a very general class of UV completions can be accurately modelled by a cutoff close to the Planck scale. In the infrared the theory tends continuously to the commutative gauge theory. If the photon contains contributions from a trace-U(1), we would observe vacuum birefringence, i.e. a polarisation dependent propagation speed, as a residual effect of the noncommutativity. Constraints on this effect require the noncommutativity scale to be close to the Planck scale.
description: 19 pages, 4 figures, 1 table
Η Επίδραση Λειτουργικών Ασκήσεων Πιλάτες στην Ικανότητα Ισορροπίας και στην Ποιότητα Ζωής Νεοτυφλοθέντων
Creators: name: Γώτης, Κωνσταντίνος Ιωάννη
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Λειτουργικές Ασκήσεις Πιλάτες
Νεοτυφλωθέντες
Functional Pilates Exercises
Individuals with Acquired Blindness

description: Σύμφωνα με τη βιβλιογραφία, τις τελευταίες δεκαετίες υπάρχει έντονο ερευνητικό ενδιαφέρον σχετικά με την μέθοδο Πιλάτες, η οποία αποτελεί ήπια, εναλλακτική και εξατομικευμένη μορφή άσκησης με ποικίλα οφέλη. Η μέθοδος απευθύνεται σε άτομα διαφόρων ηλικιών, ικανοτήτων και δυνατοτήτων. Η παρούσα έρευνα σχεδιάστηκε με στόχο να διερευνηθεί η επίδραση ενός παρεμβατικού προγράμματος άσκησης λειτουργικού τύπου Πιλάτες, στην ικανότητα ισορροπίας καθώς και στην ποιότητα ζωής νεοτυφλοθέντων ατόμων. Την παρέμβαση ολοκλήρωσαν 2 νεοτυφλοθέντες ενήλικες. Η διάρκεια του προγράμματος ήταν 12 εβδομάδες και πραγματοποιήθηκαν 24 συνεδρίες, με συχνότητα 2 συνεδρίες ανά εβδομάδα. Πραγματοποιήθηκαν μετρήσεις πριν από την αρχή και μετά το τέλος του παρεμβατικού προγράμματος. Για την μέτρηση της ικανότητας ισορροπίας χρησιμοποιήθηκαν οι δοκιμασίες Berg Balance Scale (BBS), το Stork Test (ST) και Sit To Stand (STS). Για την μέτρηση της ποιότητας ζωής χρησιμοποιήθηκε το ερωτηματολόγιο Visual Functioning Questionnaire-25 (VFQ-25). Σύμφωνα με τα αποτελέσματα, μετά το τέλος του παρεμβατικού προγράμματος διαπιστώθηκε σημαντική βελτίωση, σε ποσοστό 24,94% στο BBS, 55,52% στο Stork Test, 43,75% στο STS Test και 5,39 μονάδων Μ.Ο. ερωτηματολόγιο VFQ-25. Με βάση τα δεδομένα, ένα παρεμβατικό πρόγραμμα άσκησης λειτουργικού τύπου Πιλάτες, μπορεί να επιδράσει θετικά στην ικανότητα ισορροπίας και στην ποιότητα ζωής νεοτυφλοθέντων ατόμων.
description: According to the literature, over the last few decades, an increased research interest has been demonstrated regarding the Pilates method, which constitutes a mild, alternative and individualized form of exercise, with various benefits. This method is addressed to persons of ranging ages, capacities and abilities. The current study was designed to examine the effect of an intervening, functional-type Pilates exercise program, on balance and the quality of life of persons with acquired visual impairments. Two persons with acquired visual impairments participated in the intervention. The program duration was 12 weeks and 24 sessions were performed, with the frequency of 2 sessions per week. Measurements, at the beginning and the end of the study were taken. To measure balance ability, the Berg Balance Scale (BBS), the Stork Test (ST) and the Sit To Stand (STS) tests were used. To assess the quality of life, the Visual Functioning Questionnaire-25 (VFQ-25) was used. According to the results, after the end of the intervention program, a significant improvement was found by 24.94% in the BBS, by 55.52% in the Stork Test, by 43.75% in the STS Test and by 5.39 average in the VFQ-25 questionnaire. The results of the present study indicate that a functional-type Pilates exercise program can have positive effects on balance and quality of life of individuals with acquired visual impairment.
Minorant properties
Creators: name: Weisenhofer, Stephen
Publisher: name: University of British Columbia
Year: 2008

description: We study the minorant property and the positive minorant property for norms on spaces of matrices and norms on spaces of functions. A matrix is said to be a majorant of another if all the entries in the first matrix are greater than or equal to the absolute values of the corresponding entries in the second matrix. The Cp norm of a matrix is the tP norm of its singular values. The space of n x n matrices, with this norm, is said to have the minorant property provided that the norm of each nonnegative matrix is greater than or equal to the norm of every matrix that it majorizes. Similarly, if the norm of each nonnegative matrix is greater than or equal to the norm of every nonnegative matrix that it majorizes, then the space of matrices is said to have the positive minorant property. It is easy to verify that these properties hold if p is even. We show that the positive minorant property fails on n x n matrices with the Cp norm when 0 <p < 2(n — 1) and p is not even. We also consider versions of the minorant properties for LP-spaces of function on some commutative topological groups. We show that the positive minorant property fails on the cyclic group of order n when 0 <p < 2[(n — 1)/2] and p is not even. This relation between p and n is different from the one for matrices, and yet both seem to be optimal. We also show that the minorant property fails on cyclic groups when p and n are suitably related. We completely determine the combinations of p and n for which the minorant properties hold on some low-order groups. For compact abelian groups, we show that the positive minorant property is equivalent to a certain function operating on the class of positive definite functions. We deduce that if LP(G) has the positive minorant property, then so does LP+2 (G) .
title: Управление персоналом
Creators: name: ELS IPR BOOKS
Publisher: name: EDP Hub (Идипи Хаб), Ай Пи Ар Медиа
Year: 2024

description: Учебник является авторской версией и строится на основе предлагаемой программы, которая может быть использована в качестве типовой и модифицироваться в соответствии с требованиями высшего учебного заведения. В книге раскрыты экономические основы и особенности управления персоналом на уровне основного хозяйствующего субъекта рыночной экономики — организации. Рассматриваются концепции и стратегии управления персоналом, технологии и методы кадрового менеджмента, анализируется процесс, его функционирование, рассматриваются основные проблемы и инновации современного управления кадрами в организациях. Учебник предназначен студентам, магистрантам, докторантам специальностей 7М04103 и 6В04103 «Менеджмент», 7М04109 «Стратегический менеджмент», 6В04102 «Государственное и местное управление» и др. согласно ГОСО РК, изучающим дисциплину «Управление персоналом».
Noether Symmetry Approach in Eddington-inspired Born-Infeld gravity
Creators: name: Kanesom, Thanyagamon
name: Channuie, Phongpichit
name: Kaewkhao, Narakorn
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this work, we take a short recap of a formal framework of the Eddington-inspired Born-Infeld (EiBI) theory of gravity and derive the point-like Lagrangian for underlying theory based on the use of Noether gauge symmetries (NGS). We study a Hessian matrix and quantify Euler-Lagrange equations of EiBI universe. We discuss the NGS approach for the Eddington-inspired Born-Infeld theory and show that there exists the de Sitter solution in this gravity model.
description: v1: 13 pages, no figure
Checking the transcription of "Verdena's Life Story, Part 2"
Creators: name: Parker, Verdena
name: Newbold, Lindsey
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2022
Subjects: subject: hup

description: Audio file VP-090812-07: Checking the transcription of Verdena's Life Story part 2 (file VP-041009-02).
The Effect of Abnormal Granulation on Acoustic Wave Travel Times and Mode Frequencies
Creators: name: Petrovay, K.
name: Erdelyi, R.
name: Thompson, M. J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Observations indicate that in plage areas (i.e. in active regions outside sunspots) acoustic waves travel faster than in quiet sun, leading to shortened travel times and higher p-mode frequencies. While it is clear that the ultimate cause of any difference between quiet sun and plage is the presence of magnetic fields of order 100 G in the latter, the mechanism by which the magnetic field exerts its influence has not yet been conclusively identified. One possible such mechanism is suggested by the observation that granular motions in plage areas tend to be slightly ``abnormal'', dampened compared to quiet sun. In this paper we consider the effect that abnormal granulation observed in active regions should have on the propagation of acoustic waves. Any such effect is found to be limited to a shallow surface layer where sound waves propagate nearly vertically. The magnetically suppressed turbulence implies higher sound speeds, leading to shorter travel times. This time shift Dt is independent of the travel distance, while it shows a characteristic dependence on the assumed plage field strength. As a consequence of the variation of the acoustic cutoff with height, Dt is expected to be significantly higher for higher frequency waves within the observed regime of 3-5 mHz. The lower group velocity near the upper reflection point further leads to an increased envelope time shift, as compared to the phase shift. $p$-mode frequencies in plage areas are increased by a corresponding amount, Dnu/nu = nu*Dt. These characteristics of the time and frequency shifts are in accordance with observations. The calculated overall amplitude of the time and frequency shifts are comparable to, but still significantly (factor of 2 to 5) less than suggested by measurements.
description: 18 pages, 5 figures. Solar Phys., in press
Thermal alteration of CM carbonaceous chondrites: mineralogical changes and metamorphic temperatures
Creators: name: King, Ashley J.
name: Schofield, Paul F.
name: Russell, Sara S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: The CM carbonaceous chondrite meteorites provide a record of low temperature aqueous reactions in the early solar system. A number of CM chondrites also experienced short-lived, post-hydration thermal metamorphism at temperatures of 200C to over 750C. The exact conditions of thermal metamorphism and the relationship between the unheated and heated CM chondrites are not well constrained but are crucial to understanding the formation and evolution of hydrous asteroids. Here we have used position-sensitive-detector X-ray diffraction (PSD-XRD), thermogravimetric analysis (TGA) and transmission infrared (IR) spectroscopy to characterise the mineralogy and water contents of 14 heated CM and ungrouped carbonaceous chondrites. We show that heated CM chondrites underwent the same degree of aqueous alteration as the unheated CMs, however upon thermal metamorphism their mineralogy initially (300 to 500C) changed from hydrated phyllosilicates to a dehydrated amorphous phyllosilicate phase. At higher temperatures (over 500C) we observe recrystallisation of olivine and Fe-sulphides and the formation of metal. Thermal metamorphism also caused the water contents of heated CM chondrites to decrease from 13 wt percent to 3 wt percent and a subsequent reduction in the intensity of the 3 micron feature in IR spectra. We estimate that the heated CM chondrites have lost 15 to 65 percent of the water they contained at the end of aqueous alteration. If impacts were the main cause of metamorphism, this is consistent with shock pressures of 20 to 50 GPa. However, not all heated CM chondrites retain shock features suggesting that some were instead heated by solar radiation. Evidence from the Hayabusa2 and ORSIRS-REx missions suggest that dehydrated materials may be common on the surfaces of primitive asteroids and our results will support upcoming analysis of samples returned from asteroids Ryugu and Bennu.
description: Accepted for publication in Geochimica et Cosmochimica Acta
Finite-Temperature Form Factors: a Review
Creators: name: Doyon, Benjamin
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We review the concept of finite-temperature form factor that was introduced recently by the author in the context of the Majorana theory. Finite-temperature form factors can be used to obtain spectral decompositions of finite-temperature correlation functions in a way that mimics the form-factor expansion of the zero temperature case. We develop the concept in the general factorised scattering set-up of integrable quantum field theory, list certain expected properties and present the full construction in the case of the massive Majorana theory, including how it can be applied to the calculation of correlation functions in the quantum Ising model. In particular, we include the ''twisted construction'', which was not developed before and which is essential for the application to the quantum Ising model.
description: This is a contribution to the Proc. of the O'Raifeartaigh Symposium on Non-Perturbative and Symmetry Methods in Field Theory (June 2006, Budapest, Hungary), published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA/
Recent CLEO-c Results
Creators: name: Mendez, Hector
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Recent CLEO-c results on open and closed charm physics at center of mass of 3773 MeV (psi(3770) resonance), 4170 MeV and 3686 MeV (psi(2s) peak) are reviewed. Measurements of absolute hadronic branching ratios of D0, D+ and Ds mesons as well as charmonium spectroscopy are discussed. An outlook and future prospects for the experiment at CESR is also presented.
description: 9 pages,6 figures, contribution for the VI Latin American Symposium on High Energy Physics (SILAFAE 2006), Nov 2006, Puerto Vallarta, Mexico
AI and Democratic Education: A Critical Pragmatist Assessment
Creators: name: Wieczorek, Michał
Publisher: name: Zenodo
Year: 2024

description: This is a presentation for a talk that I delivered at the ESDiT and 4TU.Ethics conference Rethinking Ethics – Reimagining Technology at the University of Twente on 2 October 2024.

In this paper, I draw on pragmatist philosophy to assess the impact of educational AI (AIED) on the democratic dimension of education. AIED is expected to facilitate teaching and learning by personalizing content to the needs of students, automating parts of teachers’ jobs, and monitoring students’ performance and behavior, among others. However, I argue that we should pay close attention to AIED’s impact on the social development of students and the civic values and attitudes it is going to promote.

First, AIED employs questionable pedagogies by primarily framing learning as acquisition of knowledge and reducing good teaching to efficient delivery of the material. This runs contrary to the pragmatist emphasis on students’ practical engagement with the social environment which allows them to cooperatively address shared needs and perform social roles alongside others. I argue that AIED positions students as passive receivers of wisdom rather than active (future) citizens.

Second, AIED companies portray group instruction as inefficient and promote a vision in which every student has their own personal tutor (e.g., Khanmigo from Khan Academy). I argue that AIED downplays the social dimension of learning and risks depriving students of opportunities to learn how to live alongside others while getting accustomed to social differences (e.g., by observing peers from different backgrounds struggle and excel at different tasks).

Third, it is likely that the use of AIED delegate much of the instruction to technology and place the teacher in a supporting or orchestrating. However, teachers do much more than transmitting knowledge, as they develop significant relationships with their students, provide advice or care for students’ emotional needs. Most importantly for this paper, they serve as role models and an example of socially engaged citizens – a function that cannot be adequately replaced by AI.

Finally, the increased reliance on privately-owned and managed AIED subjects education to profit-seeking and increases control large tech companies have over public schools. How do we ensure that the interests and wellbeing of students are prioritized over profits and that teachers, parents and students have their say in how and why AIED is used?
Assignments of the $X(4140)$, $X(4500)$, $X(4630)$ and $X(4685)$ based on the QCD sum rules
Creators: name: Wang, Zhi-Gang
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In this article, we take into account our previous calculations based on the QCD sum rules, and tentatively assign the $X(4630)$ as the $D_s^*\bar{D}_{s1}-D_{s1}\bar{D}_s^*$ tetraquark molecular state or $[cs]_P[\bar{c}\bar{s}]_A+[cs]_A[\bar{c}\bar{s}]_P$ tetraquark state with the $J^{PC}=1^{-+}$, and assign the $X(3915)$ and $X(4500)$ as the 1S and 2S $[cs]_A[\bar{c}\bar{s}]_A$ tetraquark states respectively with the $J^{PC}=0^{++}$. Then we extend our previous works to investigate the LHCb's new tetraquark candidate $X(4685)$ as the first radial excited state of the $X(4140)$ with the QCD sum rules, and obtain the mass $M_{X}=4.70\pm0.12\,\rm{GeV}$, which is in very good agreement with the experimental value $4684 \pm 7 {}^{+13}_{-16}\,\rm{MeV}$. Furthermore, we investigate the two-meson scattering state contributions in details, and observe that the two-meson scattering states alone cannot saturate the QCD sum rules, the contributions of the tetraquark states play an un-substitutable role, we can saturate the QCD sum rules with or without the two-meson scattering states.
description: 17 pages, 2 figure
Entanglement Barriers in Dual-Unitary Circuits
Creators: name: Reid, Isaac
name: Bertini, Bruno
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: Chaotic Dynamics (nlin.CD)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: After quantum quenches in many-body systems, finite subsystems evolve non-trivially in time, eventually approaching a stationary state. In typical situations, the reduced density matrix of a given subsystem begins and ends this endeavour as a low-entangled vector in the space of operators. This means that if its operator space entanglement initially grows (which is generically the case), it must eventually decrease, describing a barrier-shaped curve. Understanding the shape of this "entanglement barrier" is interesting for three main reasons: (i) it quantifies the dynamics of entanglement in the (open) subsystem; (ii) it gives information on the approximability of the reduced density matrix by means of matrix product operators; (iii) it shows qualitative differences depending on the type of dynamics undergone by the system, signalling quantum chaos. Here we compute exactly the shape of the entanglement barriers described by different Rényi entropies after quantum quenches in dual-unitary circuits initialised in a class of solvable matrix product states (MPS)s. We show that, for free (SWAP-like) circuits, the entanglement entropy behaves as in rational CFTs. On the other hand, for completely chaotic dual-unitary circuits it behaves as in holographic CFTs, exhibiting a longer entanglement barrier that drops rapidly when the subsystem thermalises. Interestingly, the entanglement spectrum is non-trivial in the completely chaotic case. Higher Rényi entropies behave in an increasingly similar way to rational CFTs, such that the free and completely chaotic barriers are identical in the limit of infinite replicas (i.e. for the so called min-entropy). We also show that, upon increasing the bond dimension of the MPSs, the barrier maintains the same shape. It simply shifts to the left to accommodate for the larger initial entanglement.
description: 27 pages, 4 figures; v2 as appears in the journal
Οι τρόποι χρηματοδότησης νεοσύστατων εταιριών – Μελέτη περίπτωσης Ηνωμένο Βασίλειο
Creators: name: Λουκίδης, Παναγιώτης Παύλου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Νεοσύστατες επιχειρήσεις
Τραπεζικά δάνεια
Χρηματοδότηση
Funding
Business angels
Crowfunding

description: Σκοπός της παρούσας Διπλωματικής είναι να εξετάσει τους τρόπους χρηματοδότησης των νεοσύστατων επιχειρήσεων στο Ηνωμένο Βασίλειο. Συλλέγοντας πρωτογενή δεδομένα μέσω ερωτηματολογίων, η Διπλωματική διαπιστώνει ότι οι κύριες πηγές χρηματοδότησης που χρησιμοποιούν οι startups στο Ηνωμένο Βασίλειο είναι οι επιχειρηματικοί άγγελοι και τα επιχειρηματικά κεφάλαια από ιδιωτικές επιχειρήσεις, ενώ σε μικρότεροι ποσοστό χρησιμοποιούνται τα τραπεζικά δάνεια και το crowdfunding. Αντιθέτως, δεν φαίνεται να προτιμάται η λύση χρηματοδότησης από το κράτος ή την αυτοχρηματοδότηση. Οι περισσότερες επιχειρήσεις startups του Ηνωμένου Βασιλείου βρίσκονται σε στάδιο επέκτασης ή σε στάδιο ανάπτυξης, ενώ αρκετές βρίσκονται σε στάδιο αρχικής επένδυσης ή σε πολύ αρχικό στάδιο. Τέλος, οι ευκαιρίες χρηματοδότησης που οδηγούν τους επενδυτές στις startups του Ηνωμένου Βασιλείου φαίνεται να είναι κυρίως οι πολλοί και διαφορετικοί τρόποι χρηματοδότησης και οι διαφορετικοί τομείς στους οποίους δραστηριοποιούνται οι startups της χώρας. Η Διπλωματική καταλήγει στο συμπέρασμα ότι η χρηματοοικονομική παιδεία του ιδρυτή για την εκτίμηση των χρηματοδοτικών αναγκών της νεοσύστατης επιχείρησης και η ικανότητά του να εξασφαλίσει αυτούς τους πόρους για την ανάπτυξη της επιχείρησης είναι πολύ σημαντικοί κινητήριοι παράγοντες των επιχειρηματικών συμμετοχών. Επιπλέον, η επιτυχία στις διαπραγματεύσεις για την απόκτηση χρηματοδότησης και ο σχεδιασμός των startups συμβάλλον στην αποτελεσματική έναρξη λειτουργίας.
description: The purpose of this Dissertation is to examine the ways that the UK startups are funded. By collecting primary data through questionnaires, the Dissertation finds that the main sources of funding used by the UK startups are business angels and venture capital from private companies, while bank loans and crowdfunding are used at a smaller rate. On the contrary, state financing or self-financing do not seem to be preferable. Most UK startups are in an expanding or development stage while others are at the initial investment or at a very early stage. Finally, the funding opportunities that drive investors to UK startups seem to be mainly the different ways of financing and the different sectors in which the UK startups operate. The Dissertation concludes that the financial literacy of the founder for the assessment of the financial needs of the startup and the ability to secure these resources for the development of the business are both significant drivers of business participation. In addition, success in the financing negotiations and the design of startups contribute to the effective development of the startups.
Weakly bound $H$ dibaryon from SU(3)-flavor-symmetric QCD
Creators: name: Green, Jeremy R.
name: Hanlon, Andrew D.
name: Junnarkar, Parikshit M.
name: Wittig, Hartmut
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present the first study of baryon-baryon interactions in the continuum limit of lattice QCD, finding unexpectedly large lattice artifacts. Specifically, we determine the binding energy of the $H$ dibaryon at a single quark-mass point. The calculation is performed at six values of the lattice spacing $a$, using O($a$)-improved Wilson fermions at the SU(3)-symmetric point with $m_π=m_K\approx 420$ MeV. Energy levels are extracted by applying a variational method to correlation matrices of bilocal two-baryon interpolating operators computed using the distillation technique. Our analysis employs Lüscher's finite-volume quantization condition to determine the scattering phase shifts from the spectrum and vice versa, both above and below the two-baryon threshold. We perform global fits to the lattice spectra using parametrizations of the phase shift, supplemented by terms describing discretization effects, then extrapolate the lattice spacing to zero. The phase shift and the binding energy determined from it are found to be strongly affected by lattice artifacts. Our estimate of the binding energy in the continuum limit of three-flavor QCD is $B_H^{\text{SU(3)}_{\rm f}}=4.56\pm1.13_{\rm stat}\pm0.63_{\rm syst}$ MeV.
description: 8 pages, 5 figures, plus supplemental material (10 pages, 10 figures, 2 tables) and spectrum data file (HDF5 format). v2: new finer ensemble, revised analysis with more conservative uncertainties in the spectrum, more details in the supplemental material, and additional references
Η παύση της πληρεξουσιότητας
Creators: name: Πέσιος, Νικόλαος Κωνσταντίνου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Πληρεξουσιότητα
Παύση πληρεξουσιότητας
Καλή πίστη
Procuration
End of procuration
Good faith

description: Η εργασία εστιάζει στο ζήτημα της παύσης της πληρεξουσιότητας κατά το ελληνικό αστικό δίκαιο και διακρίνεται σε δύο μέρη. Στο πρώτο μέρος, εξετάζονται οι λόγοι που επιφέρουν την παύση, οι οποίοι διακρίνονται σε ειδικούς, που προβλέπονται νομοθετικά στις ΑΚ 218-223, και γενικούς, που συνάγονται ερμηνευτικά. Από τους γενικούς λόγους παύσης, αναλυτικά εξετάζεται η παραίτηση του πληρεξουσίου, ενώ αναλύονται και οι ειδικοί λόγοι, δηλαδή η ανάκληση, στην ενότητα της οποίας γίνεται ιδιαίτερη μνεία στην αμετάκλητη πληρεξουσιότητα, η λήξη της εσωτερικής σχέσης, ο θάνατος (με ενδελεχή αναφορά στην κληρονομητή και τη μεταθανάτια πληρεξουσιότητα), η επιγενόμενη δικαιοπρακτική ανικανότητα, η διάλυση νομικού προσώπου και η πτώχευση. Στο δεύτερο μέρος, εξετάζονται οι συνέπειες της παύσης της πληρεξουσιότητας. Αρχικά, εξετάζονται η υποχρέωση του κυρίου των υποθέσεων να ενημερώσει τον πληρεξούσιο και τους τρίτους για την παύση και η τύχη του πληρεξουσίου εγγράφου (ΑΚ 227-228). Στη συνέχεια, επιχειρείται η συστηματική εξέταση των ΑΚ 224-225 σε συνδυασμό και με τις ΑΚ 229επ., για τη διερεύνηση της τύχης των δικαιοπραξιών που καταρτίζονται μετά την παύση της πληρεξουσιότητας και την υποχρέωση του κυρίου των υποθέσεων σε εύλογη αποζημίωση του τρίτου
description: This paper focuses on the issue of the end of procuration under Greek civil law and is divided into two parts. In the first part, the reasons for the end of procuration are examined, and are divided into special reasons, which are the ones provided by law, in articles 218-223 of Greek Civil Code, and general reasons, which are the ones concluded interpretatively. From the general reasons of the end, the renunciation of procuration is examined in detail, while special reasons are also analyzed, i.e. the revocation, in the section of which special mention is made of irrevocable procuration, the termination of the internal relationship, death (with elaborate reference to trans-mortem and post-mortem procuration), subsequent legal incapacity, dissolution of a legal entity and bankruptcy. In the second part, the consequences of the end of procuration are examined. Initially, the obligation of the principal to inform the proxy and the third parties about the end and the fate of the document of procuration (Greek C.C. 227-228) are examined. Then follows the systematic examination of articles 224-225 GreekCC in combination with articles 229 et seq. GreekCC, which is undertaken in order to investigate the fate of legal acts drawn up after the cessation of procuration and the obligation of the principal to reasonable compensation of the third party
Leveraging Machine Learning For Sustainable Investment: Evaluating The Predictive Power Of ESG Metrics On Funding Allocations
Creators: name: Joseph Okpono
Publisher: name: Zenodo
Year: 2024

description: The integration of Environmental, Social, and Governance (ESG) factors into financial modeling hasbecome very crucial, as investors explore investment strategies for sustainable and responsible investment. Thisstudy probes how the use of Machine Learning (ML) techniques can be used to predict and allocate funding,based on ESG performance of an organization. The key objective is to evaluate the predictive accuracy ofdifferent ML models, in quantitatively forecasting funding allocations using ESG metrics. Dataset such as ESGmetrics and financial indicators including revenue and profit were collected from different companies. Toimprove the model’s predictability, feature engineering which involves creating new features that combine ESGmetrics with financial indicators to capture complex relationships affecting funding allocations was used. Theanalysis results indicate that the Random Forest model achieved the highest predictive accuracy, with an R² valueof 0.8657, demonstrating its robustness in managing complex, non-linear relationships within the dataset.Insights from the Feature Importance Analysis revealed that social and governance-related metrics, such asSocial Score Profit and Governance Score Profit, were the most significant predictors of funding received. Boththe Random Forest and Gradient Boosting ensemble methods outperformed traditional regression and SVMmodels in predicting funding allocations based on ESG performance, demonstrating their effectiveness inrevealing operational risks and opportunities. The findings from the study highlights the value ML models, suchas the ensemble methods, give in guiding investors towards companies with good social responsibility and ethicalpractices.
Connecting Low Energy Leptonic CP-violation to Leptogenesis
Creators: name: Pascoli, S.
name: Petcov, S. T.
name: Riotto, A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: It was commonly thought that the observation of low energy leptonic CP-violating phases would not automatically imply the existence of a baryon asymmetry in the leptogenesis scenario. This conclusion does not generically hold when the issue of flavour is relevant and properly taken into account in leptogenesis. We illustrate this point with various examples studying the correlation between the baryon asymmetry and the CP-violating asymmetry in neutrino oscillations and the effective Majorana mass in neutrinoless double beta decay.
description: 4 pages, 3 figures, LaTeX file. Some typos corrected, one figure added
Braided $L_{\infty}$-Algebras, Braided Field Theory and Noncommutative Gravity
Creators: name: Ćirić, Marija Dimitrijević
name: Giotopoulos, Grigorios
name: Radovanović, Voja
name: Szabo, Richard J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: Quantum Algebra (math.QA)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We define a new homotopy algebraic structure, that we call a braided $L_\infty$-algebra, and use it to systematically construct a new class of noncommutative field theories, that we call braided field theories. Braided field theories have gauge symmetries which realize a braided Lie algebra, whose Noether identities are inhomogeneous extensions of the classical identities, and which do not act on the solutions of the field equations. We use Drinfel'd twist deformation quantization techniques to generate new noncommutative deformations of classical field theories with braided gauge symmetries, which we compare to the more conventional theories with star-gauge symmetries. We apply our formalism to introduce a braided version of general relativity without matter fields in the Einstein-Cartan-Palatini formalism. In the limit of vanishing deformation parameter, the braided theory of noncommutative gravity reduces to classical gravity without any extensions.
description: 68 pages; v2: presentation improved, references added; Final version to be published in Letters in Mathematical Physics
High-Resolution Radar via Compressed Sensing
Creators: name: Herman, Matthew A.
name: Strohmer, Thomas
Publisher: name: arXiv
Year: 2008
Subjects: subject: Numerical Analysis (math.NA)
subject: Information Theory (cs.IT)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences

description: A stylized compressed sensing radar is proposed in which the time-frequency plane is discretized into an N by N grid. Assuming the number of targets K is small (i.e., K much less than N^2), then we can transmit a sufficiently "incoherent" pulse and employ the techniques of compressed sensing to reconstruct the target scene. A theoretical upper bound on the sparsity K is presented. Numerical simulations verify that even better performance can be achieved in practice. This novel compressed sensing approach offers great potential for better resolution over classical radar.
description: New: Extended theory to include case of noisy signals; Re-ran numerical simulations with complex-valued data; Clarified definition of "random signal"; Minor language and typo fixes; 14 pages, 13 figures. Accepted to IEEE Transactions on Signal Processing, December 2008
Transcription of file 028_A (collection LA 256)
Creators: name: Parker, Verdena
name: Newbold, Lindsey
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2022
Subjects: subject: hup

description: Audio file VP-090812-06: Transcription of file 028_A (referred to here as 029_A) from LA 256 (a collection of recordings given to the Berkeley Language Center by Verdena), from 15:55 to 17:06. The file was assigned a provisional identifier 029_A that was changed to 028_A in the final cataloging for the collection; file 028_A was subsequently assigned the identifier LA256.028A and associated with the bundle LA256.028 in the California Language Archive.
Μελέτη στατιστικών στοιχείων της οδικής ασφάλειας για την Ελλάδα, την Ευρώπη και την υφήλιο
Creators: name: Παπανικολάου, Πασχαλίνα Βασιλείου
Publisher: name: Aristotle University of Thessaloniki
Year: 2020
Subjects: Οδικό ατύχημα
Οδική ασφάλεια
Δείκτες
Road accident
Road safety
Indicators

description: Η παρούσα διπλωματική αφορά την μελέτη των οδικών ατυχημάτων στην υφήλιο, στην Ευρώπη και στην Ελλάδα, μέσω στατιστικών μεθόδων και χαρτών. Το χρονικό διάστημα που μελετάται είναι από το έτος 2005 έως και το 2017. Το οδικό ατύχημα αφορά ένα συμβάν που έχει ως αποτέλεσμα τις υλικές ζημιές των οχημάτων, τον τραυματισμό ή το θάνατο ενός ατόμου με ένα ή και περισσότερα εμπλεκόμενα οχήματα στο οδικό δίκτυο. Η μελέτη επεκτείνεται στην ανάλυση των οδικών ατυχημάτων αρχικά ως απόλυτος αριθμός (νεκροί, τραυματίες και ατυχήματα), έπειτα μέσω δεικτών και άλλων παραγόντων που αφορούν το οδικό δίκτυο, τους χρήστες, το ΑΕΠ και άλλα. Αποτέλεσμα των προαναφερθέντων είναι η σχέση των οδικών ατυχημάτων με την οικονομία, την κοινωνία και την βελτίωση της οδικής ασφάλειας
description: This dissertation is concerned with the study of road accidents in the world, in Europe and in Greece, through statistical methods and maps. The period considered is from 2005 to 2017 . The road accident involves an incident that results in the material damage of vehicles, the injury or death of a person with one or more vehicles involved on the road network. The study extends to the analysis of road accidents initially as an absolute number (dead, injured and accidents), then through indicators and other factors concerning the road network, the users, GDP and others. As aresult, road accidents are linked to the economy, society and improving road safe
The impact of baryonic physics on the abundance, clustering, and concentration of halos
Creators: name: Beltz-Mohrmann, Gillian D.
name: Berlind, Andreas A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We examine the impact of baryonic physics on the halo distribution in hydrodynamic simulations (Illustris, IllustrisTNG, and EAGLE), particularly with regards to how it differs from that in dark matter only (DMO) simulations. We find that, in general, DMO simulations produce halo mass functions (HMF) that are shifted to higher halo masses than their hydrodynamic counterparts, due to the lack of baryonic physics. However, the exact nature of this mass shift is a complex function of mass, halo definition, redshift, and larger-scale environment, and it also depends on the specifics of the baryonic physics implemented in the simulation. We present fitting formulae for the corrections one would need to apply to each DMO halo catalogue in order to reproduce the HMF found in its hydrodynamic counterpart. We provide these formulae for all three simulations, for five different halo definitions at redshifts 0, 1, and 2. Additionally, we explore the dependence on environment of this HMF discrepancy, and find that, in most cases, halos in low density environments are slightly more impacted by baryonic physics than halos in high density environments. We thus also provide environment-dependent mass correction formulae that can reproduce the conditional, as well as global, HMF. We show that our mass corrections also repair the large-scale clustering of halos, though the environment-dependent corrections are required to achieve an accuracy better than 2%. Finally, we examine the impact of baryonic physics on the halo mass - concentration relation, and find that its slope in hydrodynamic simulations is consistent with that in DMO simulations. Ultimately, we recommend that any future work relying on DMO halo catalogues incorporate our mass corrections to test the robustness of their results to baryonic effects.
description: 18 pages, 7 figures, accepted to ApJ