cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Κοσμολογικά σενάρια σε έξτρα διαστάσεις
Creators: name: Καραγιαννάκης, Νικόλαος Χρήστου
Publisher: name: Aristotle University of Thessaloniki
Year: 2007
Subjects: Εξτρα διαστάσεις
Κοσμολογία
Θεωρία Kaluza-Klein
Θεωρία επαγόμενης μάζας
Θεώρημα του Campbell
Γενική σχετικότητα
Extra dimensions
Cosmology
Kaluza-Klein theory
Induced mass theory
Campbell theorem
General relativity

description: Στην εργασία αυτή εξετάζουμε το πώς μπορεί να περιγραφεί η ύλη στο τετραδιάστατο σύμπαν ως αποτέλεσμα της ύπαρξης μις ή περισσοτέρων έξτρα διαστάσεων. Στο πρώτο κεφάλαιο ξεκινάμε με μια σύντομη περιγραφή του τι είναι κοσμολογικό μοντέλο. Στο δεύτερο κεφάλαιο γνωρίζουμε τα βασικά στοιχεία της γενικής θεωρίας της σχετικότητας τα οποία χρησιμοποιούνται στην κοσμολογία. Στο επόμενο κεφάλαιο γίνεται μια εισαγωγή στη δυναμική εξέλιξη του σύμπαντος, καθώς και στα πιο βασικά στοιχεία της θεωρίας πληθωρισμού. Η εισαγωγή ολοκληρώνεται στο κεφάλαιο 4, όπου δίνονται κάποιοι ορισμοί σε βασικά θέματα της διαφορικής γεωμετρίας, καθώς και μια περίληψη της προόδου επάνω στις έξτρα διαστάσεις, λαμβάνοντας υπόψιν τη συνθήκη κυλινδρικότητας. Στο έκτο κεφάλαιο δουλεύουμε αντίστοιχα, χωρίς όμως να λάβουμε υπόψιν τη συνθήκη αυτή.Τέλος στο τελευταίο κεφάλαιο γίνονται κάποιες σκέψεις επάνω στο θέμα των έξτρα διαστάσεων στην κλασσική φυσική
description: We study how matter in a 4d universe can be described as a result of extra dimensions. On the first chapter we start with a short description of a cosmological model. On the second chapter we examine the basic mathematical tools from general relativity which are used in cosmology. On the next chapter there is an introduction to the dynamical expansion of universe and the basic elements on inflation theory. On chapter four we give some differential geometry definitions as well as a short history of the progress being made on extra dimensions. On chapters five and six we study induced mass theory with and without cylindricity respectively. Finally we make some thoughts on extra dimensions in classical physics
Dynamics of milling flexible structures
Creators: name: Campomanes, Marc Lorenz
Publisher: name: University of British Columbia
Year: 2009

description: Peripheral milling of aerospace parts takes a considerable amount of manufacturing time on production floors. Recently, due to fatigue constraints and advances in high speed machining, aircraft components are machined as monolithic parts from solid blanks. This thesis focuses on the mathematical modeling of peripheral milling of aerospace parts with thin walls. The varying dynamics along the contact length of both the part and the cutter are considered. The structural dynamics of a flexible thin web and of the end mill are modelled as discrete models, whose modal parameters are identified experimentally. The kinematics of peripheral milling is modelled in the time domain. The chip removed at any point along the workpiece/ cutter contact length is predicted, including the influence of structural dynamic displacements of both the cutter and the workpiece at present and previous tooth passing intervals. The cutting forces are predicted as being proportional to the time varying dynamic chip loads. The time domain model of the process includes various non-linearities in the process such as the separation of the tool from the workpiece due to excessive vibrations. The time domain algorithm can predict the cutting load distribution on both cutter and thin web structures, dimensional surface finish of the part, vibrations, torque, power and bending load experienced by the lower spindle bearing of the machine tool. The predictions are verified experimentally by conducting numerous cutting tests. The accurate time domain simulations of dynamic milling have shown that large feed rates affect the chatter stability at low cutting speeds. This phenomenon has not been previously reported in the literature. An analytical model of the dynamic milling system with the influence of feed on the regenerative phase shift has been developed, and the stability of the system is solved analytically in the frequency domain. The developed time domain simulations of the process support the linear analytical solution. The mathematical models and algorithms developed in this thesis have been experimentally verified and have been used in peripheral milling of aircraft wing components in industry.
Η οικονομική συμπεριφορά των σπουδαστών στην Ελλάδα. Βαθμός χρέωσης και μελλοντικές τάσεις. Υπάρχει λόγος ανησυχίας ;
Creators: name: Βλάχου, Μαρία Δημητρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2007
Subjects: Δανεισμός
Φοιτητές
Πιστωτικές κάρτες
Χρέος
Φοιτητικά δάνεια
Οικονομικές δυσκολίες
Student debt
Credit cards
Loans Greece
Economic difficulties
Student loans

description: Με αφορμή τις ανησυχητικές διαστάσεις που έχει λάβει το φαινόμενο του δανεισμού των φοιτητών σε πολλά κράτη του εξωτερκού, επιχειρείται η εξέτασή του και στην ελληνική πραγματικότητα. Η χρήση των πιστωτικών καρτών και η λήψη φοιτητικών ή μη δανείων είναι ευρέως διαδεδομένα τόσο στην Ευρώπη όσο και στις ΗΠΑ, ενώ στην Ελλάδα τα μεγέθη εμφανίζονται μειωμένα σε σύγκριση με το εξωτερικό αλλα εφιστούν την προσοχή στο ζήτημα. Παρατηρήθηκε μια σχετική ανεκτικότητα απέναντι στην έννοια του χρέους, η προθυμία για τη συνέχιση της χρήσης μέσω πίστωσης από τους σπουδαστές που ήδη τα χρησιμοποιούν και μια γενικότερη τάση για τη λήψη δανείων μελλοντικά. Παράλληλα διαπιστώθηκε η ύπαρξη οικονομικών δυσκολιών τόσο από τους φοιτητές όσο και από τις οικογένειές τους, στην ανταπόκριση των δαπανών που συνεπάγονται οι σπουδές
description: Due to the worrying dimensions that the phenomenon of lending of students has received in a lot of states of abroad, its examination is attempted in the greek reality as well. The use of credit cards and the reception of student loans and other type of loans have become common and are widespread in Europe and in Usa and although the sizes are presented decreased in Greece compare to the countries abroad, they do draw attention to this matter. A relative tolerance in the significance of debt was observed, as well as an eagerness to continue the use of credit means especially from the students that already make use of them and also a general tendency for a future increase in the reception of loans was reported. At the same time, the existence of economic difficulties for the students individually but also for their families to respond to the education expenses was realized
Jet quenching with $T$-dependent running coupling
Creators: name: Zakharov, B. G.
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We perform an analysis of jet quenching in heavy ion collisions at RHIC and LHC energies with the temperature dependent running QCD coupling. Our results show that the $T$-dependent QCD coupling largely eliminates the difference between the optimal values of $α_s$ for the RHIC and LHC energies. It may be viewed as direct evidence of the increase of the thermal suppression of $α_s$ with rising temperature.
description: 7 pages, 3 figures, accepted for publication in JETP Letters. arXiv admin note: text overlap with arXiv:2007.09772
Η φιλοσοφία της γλώσσας στους στωικούς
Creators: name: Ηλιάδου, Ιωάννα Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2007
Subjects: Στωικοί
Γλώσσα
Λογική
Διαλεκτική
Ρητορική
Λέκτον
Stoic
Language
Logic
Dialect
Rhetorical
Lekton

description: Η φιλοσοφία της γλώσσας των στωικών εντάσσεται στη γενικότερη θεωρία τους περί λογικής, η οποία διαιρείται σε δύο τμήματα, τη ρητορική και τη διαλεκτική. Η πρώτη συνίσταται στην ικανότητα του ομιλητή να πείθει ενώ η δεύτερη στην ικανότητά του να συμμετέχει σε έναν διάλογο, στην ικανότητα να διαλέγεται. Για τους στωικούς η διαλεκτική είναι η επιστήμη των λεκτών, δηλαδή της λεκτικής έκφρασης. Τα λεκτά αυτά δηλώνουν τα γεγονότα γύρω μας. Η αλήθεια ή το ψεύδος δεν συνίστατι σε αυτά αλλά στα αξιώματα που προκύπτουν από αυτά, στις προτάσεις δηλαδή που τα περιέχουν. Την αλήθεια αυτή ο άνθρωπος τη διακρίνει μέσω της καταληπτικής του φαντασίας. Η στωική φιλοσοφία της γλώσσας μπορεί να αποσαφηνιστεί μονάχα με την παράλληλη μελέτη της θεωρίας των λεκτών
description: The philosophy of the stoics language is a part of the general theory of logic, which is divided in two parts. The rhetorical and the dialect. The first refers to the speaker's ability to convince and the second one, to the ability of participate in a conversation. The ability to discuss for the stoics philosophers dialect in the science of the lekton. This emans the expression of "lekta". The "lekta" state the facts around us. The truth and the lie don't exist in the "lekta" but in the propositions of the "lekta". This truth can be understood by our ecatalyptical imagination. The stoic philosophy of the language can be more clear by the parlle study of the theory of the "lekta"
Robust Optimization Approaches for Portfolio Selection: A Computational and Comparative Analysis
Creators: name: Georgantas, A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Portfolio Management (q-fin.PM)
subject: Optimization and Control (math.OC)
subject: FOS: Economics and business
subject: FOS: Mathematics

description: The field of portfolio selection is an active research topic, which combines elements and methodologies from various fields, such as optimization, decision analysis, risk management, data science, forecasting, etc. The modeling and treatment of deep uncertainties for future asset returns is a major issue for the success of analytical portfolio selection models. Recently, robust optimization (RO) models have attracted a lot of interest in this area. RO provides a computationally tractable framework for portfolio optimization based on relatively general assumptions on the probability distributions of the uncertain risk parameters. Thus, RO extends the framework of traditional linear and non-linear models (e.g., the well-known mean-variance model), incorporating uncertainty through a formal and analytical approach into the modeling process. Robust counterparts of existing models can be considered as worst-case re-formulations as far as deviations of the uncertain parameters from their nominal values are concerned. Although several RO models have been proposed in the literature focusing on various risk measures and different types of uncertainty sets about asset returns, analytical empirical assessments of their performance have not been performed in a comprehensive manner. The objective of this study is to fill in this gap in the literature. More specifically, we consider different types of RO models based on popular risk measures and conduct an extensive comparative analysis of their performance using data from the US market during the period 2005-2016.
description: 64 pages, MSc Thesis, Department of Production Engineering and Management, Technical University of Crete
Ο ευαγγελιστής Λουκάς ζωγράφος της Παναγίας
Creators: name: Σαμολαδά, Αγνή Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2007
Subjects: Ευαγγελιστής Λουκάς
Ζωγράφος
Παναγία
Luke evangelist
Loukas as painter
Mother of God

description: Η παρούσα εργασία μελετά την παράδοση εκείνη που θέλει τον ευαγγελιστή Λουκά να έχει φιλοτεχνήσει την εικόνα της Παναγίας. Για τη διερεύνηση του θέματος γίνεται μια προσπάθεια να συγκεντρωθεί και να αναλυθεί το σύνολο εκείνο των γραπτών πηγών και εικόνων που μας παρέχει η βιβλιογραφία από την προεικονομαχική περίοδο μέχρι και τη μεταβυζαντινή εποχή
description: This study has to do with the tradition according to which evangelist Loukas is the painter of theicon Mother of God. At this paper it has been collected, Luke analysed the whole number of the written sources and icons saved by the bibliography from the 7th century until the post byzantine years
Magnetic state and electronic structure of plutonium from ``first principles'' calculations
Creators: name: Anisimov, V. I.
name: Shorikov, A. O.
name: Kuneš, J.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The goal to describe plutonium phases from ``first principles'' calculation methods is complicated by the problem of 5f-electrons localization. While for early actinides (Th, U,Np) standard DFT (Density Functional Theory) description with itinerant 5f-electrons works well for late actinides (Am, Cm) DFT calculations with completely localized (pseudocore) 5f-electrons give satisfactory results. However plutonium presents a border case of partial localization and both limits (itinerant and completely localized) are not valid. We present a review of the methods used to solve this problem and discuss what could be the reasons for their successes and failures.
description: 19 pages, 18 figures, to be published in The Journal of Alloys and Compounds
The origin of infinitely divisible distributions: from de Finetti's problem to Levy-Khintchine formula
Creators: name: Mainardi, Francesco
name: Rogosin, Sergei
Publisher: name: arXiv
Year: 2008
Subjects: subject: History and Overview (math.HO)
subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60E07; 60E10; 60G51; 01A70

description: The article provides an historical survey of the early contributions on infinitely divisible distributions starting from the pioneering works of de Finetti in 1929 up to the canonical forms developed in the thirties by Kolmogorov, Levy and Khintchine. Particular attention is paid to single out the personal contributions of the above authors that were published in Italian, French or Russian during the period 1929-1938. In Appendix we report the translation from the Russian into English of a fundamental paper by Khintchine published in Moscow in 1937.
description: 26 pages
On the image of the trivial source ring in the ring of virtual characters of a finite group
Creators: name: McHugh, John Revere
Publisher: name: arXiv
Year: 2020
Subjects: subject: Representation Theory (math.RT)
subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 19A22, 20C20

description: We examine the cokernel of the canonical homomorphism from the trivial source ring of a finite group to the ring of $p$-rational complex characters. We use Boltje and Coşkun's theory of fibered biset functors to determine the structure of the cokernel. An essential tool in the determination of this structure is Bouc's theory of rational $p$-biset functors.
Quantum families of maps and quantum semigroups on finite quantum spaces
Creators: name: Soltan, Piotr M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Operator Algebras (math.OA)
subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics
subject: 46L89, 20M20, 58B32, 58B34

description: Quantum families of maps between quantum spaces are defined and studied. We prove that quantum semigroup (and sometimes quantum group) structures arise naturally on such objects out of more fundamental properties. As particular cases we study quantum semigroups of maps preserving a fixed state and quantum commutants of given quantum families of maps.
description: update: last section generalized to non-tracial states
EXPLORING THE RELATIONSHIP BETWEEN METACOGNITIVE AWARENESS AND FORMATIVE ASSESSMENT PRACTICES IN HIGHER EDUCATION: A CASE STUDY APPROACH
Creators: name: Khakimxodjayev, Nodir
Publisher: name: Zenodo
Year: 2025

description: this thesis explores the relationship between metacognitive awareness and formative assessment practices in higher education through a case study approach. Metacognition, or the awareness of one's cognitive processes, plays a significant role in enhancing student learning by enabling students to regulate their learning activities more effectively. Formative assessment, defined as ongoing feedback during the learning process, provides critical opportunities for students to monitor and adjust their learning strategies. The purpose of this study is to investigate how metacognitive awareness influences students' responses to formative assessment practices and how these assessments, in turn, foster the development of metacognitive skills.
Γυναίκες και νέες τεχνολογίες: "λόγοι" φοιτητριών για τους υπολογιστές
Creators: name: Παντούλη, Ολγα Παναγιώτη
Publisher: name: Aristotle University of Thessaloniki
Year: 2007
Subjects: Υπολογιστές στην εκπαίδευση
Γυναίκες
Υπολογιστές-κοινωνικές απόψεις
Ανάλυση λόγου
Computers in education
Women
Computers-social aspects
Discourse analysis

description: Η εργασία αποτελεί προσπάθεια να καταγραφούν και να αναλυθούν οι "λόγοι" νέων γυναικών οι οποίες καλούνται να επιχειρηματολογήσουν για τη σχέση τους με τους υπολογιστές και για τον τρόπο που βιώνουν τη μειωμένη τους ενασχόληση με τους υπολογιστές. Είναι μια προσπάθεια να ερμηνεύσουμε τους τρόπους με τους οποίους δομούν τη θηλυκή τους ταυτότητα σε σχέση με τους υπολογιστές και τους τρόπους με τους οποίους οι κοινωνικές πρακτικές διαμορφώνουν τη σχέση αυτή. Το ερευνητικό εργαλείο της έρευνας είναι οι ομάδες εστίασης και η μεθοδολογία ανάλυσης των απομαγνητοφωνημένων συζητήσεων μέσα στις ομάδες εστίασης είναι η φεμινιστική κριτική ανάλυσης λόγου. Τα υποκείμενα της έρευνας είναι πρωτοετείς φοιτήτριες του τμήματος Φιλοσοφίας και Παιδαγωγικής (πρωτοετείς το εξάμηνο που διεξήχθη η έρευνα, Νοέμ. 2003)
description: As part of the requirements of an MA thesis a research was conducted aiming to explore the subjective beliefs and the female student's discourses in relation to computers. The analysis of the texts was conducted using the feminist critical discourse analysis. On the basis of what female students said, applying the focus group method specific patterns are formed in the way they view themselves in relation to computers
On the delay times of merging double neutron stars
Creators: name: Greggio, Laura
name: Simonetti, Paolo
name: Matteucci, Francesca
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The merging rate of double neutron stars (DNS) has a great impact on many astrophysical issues, including the interpretation of gravitational waves signals, of the short Gamma Ray Bursts (GRBs), and of the chemical properties of stars in galaxies. Such rate depends on the distribution of the delay times (DDT) of the merging events. In this paper we derive a theoretical DDT of merging DNS following from the characteristics of the clock controlling their evolution. We show that the shape of the DDT is governed by a few key parameters, primarily the lower limit and the slope of the distribution of the separation of the DNS systems at birth. With a parametric approach we investigate on the observational constraints on the DDT from the cosmic rate of short GRBs and the Europium to Iron ratio in Milky Way stars, taken as tracer of the products of the explosion. We find that the local rate of DNS merging requires that about 1 percent of neutron stars progenitors live in binary systems which end their evolution as merging DNS within a Hubble time. The redshift distribution of short GRBs does not yet provide a strong constraint on the shape of the DDT, although the best fitting models have a shallow DDT. The chemical pattern in Milky Way stars requires an additional source of Europium besides the products from merging DNS, which weakens the related requirement on the DDT. At present both constraints can be matched with the same DDT for merging DNS.
description: 18 pages, to appear in MNRAS
Blockchain Technology: Methodology, Application and Security Issues
Creators: name: Haque, AKM Bahalul
name: Rahman, Mahbubur
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Blockchain technology is an interlinked systematic chain of blocks that contains transaction history and other user data. It works under the principle of decentralized distributed digital ledger. This technology enables cryptographically secure and anonymous financial transactions among the user nodes of the network enabling the transactions to be validated and approved by all the users in a transparent environment. It is a revolutionary technology that earned its emerging popularity through the usage of digital cryptocurrencies. Even though Blockchain holds a promising scope of development in the online transaction system, it is prone to several security and vulnerability issues. In this paper, blockchain methodology, its applications, and security issues are discussed which might shed some light on blockchain enthusiasts and researchers.
description: 10 pages, 14 Figures and 4 Tables
Cooperatives as vehicles for community and economic development : a case for alternative ownership and expansion of the solidarity economy in Austin, Texas
Creators: name: Vallier, Shaw
Publisher: name: The University of Texas at Austin
Year: 2023
Subjects: Cooperatives
Employee-ownership
Housing
Anti-displacement
Community development
Economic development

description: Rapidly rising home prices in and around Austin, Texas has led to the displacement of residents, which in turn results in loss of community as well as increased traffic as most workers still need to access jobs near the city center. Increasing support for worker-owned firms and housing cooperatives could be community and economic development strategies for stabilizing residents. Cooperatives were able to better weather economic downturns brought on by COVID, keeping more workers employed and paid. This report uses review of existing literature, case studies, and analysis of secondary data sources to identify advantages as well as specific areas for intervention in both the productive enterprise and housing sectors. Austin has a small but established cooperative ecosystem that can continue to contribute to the growth of the solidarity economy in the area. This report specifically explores alternative models of ownership for firms and housing as a strategy for community development, and further, as strategies that will maximize the benefits of the systems already in place. The overarching point, however, is that alterative models of ownership would lend themselves well to the objectives of 1) ensuring that the incredible growth the region continues to see is sustainably and equitably distributed, 2) supporting the leveraging of community resources to return community benefits, wherever possible, and 3) to support parallel strengthening of worker and resident movements in the face of increasing returns to global investors
The wetting problem of fluids on solid surfaces. Part 2: the contact angle hysteresis
Creators: name: Gouin, Henri
Publisher: name: arXiv
Year: 2008
Subjects: subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: In part 1, we proposed a model of dynamics of wetting for slow movements near a contact line formed at the interface of two immiscible fluids and a solid when viscous dissipation remains bounded. The contact line is not a material line and a Young-Dupré equation for the apparent dynamic contact angle taking into account the line celerity was proposed. In this paper we consider a form of the interfacial energy of a solid surface in which many small oscillations are superposed on a slowly varying function. For a capillary tube, a scaling analysis of the microscopic law associated with the Young-Dupré dynamic equation yields a macroscopic equation for the motion of the contact line. The value of the deduced apparent dynamic contact angle yields for the average response of the line motion a phenomenon akin to the stick-slip motion of the contact line on the solid wall. The contact angle hysteresis phenomenon and the modelling of experimentally well-known results expressing the dependence of the apparent dynamic contact angle on the celerity of the line are obtained. Furthermore, a qualitative explanation of the maximum speed of wetting (and dewetting) can be given.
description: Preprint 26 pages
Νοήματα αρίθμησης και μέτρησης στο σχολικό και στο ευρύτερο κοινωνικό περιβάλλον του παιδιού: η περίπτωση της αριθμογραμμής
Creators: name: Γκριμπίζη, Ολυμπία Φωτίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2007
Subjects: Αρίθμηση στο δημοτικό
Τυπικό/άτυπο Μαθηματικά
Κριτική ψυχολογία
Διαλογικές πρακτικές
Υποκειμενικότητα
Κατασκευή νοήματος
Arithmacy at primary school
Formal and informal mathematics
Critical psychology
Discursive practices
Subjectivity
Construction of meaning

description: Στην παρούσα εργασία αναζητήσαμε τα νοήματα της αρίθμησης και της μέτρησης σε κοινωνιο-πολιτισμικά περιβάλλοντα, μέσα στις λειτουργίες του λόγου και τις κοινωνικές πρακτικές. Προσπαθήσαμε να δούμε κάτω από ποιες προϋποθέσεις μπορούν οι γνώσεις που κατέχουν τα παιδιά από τη συμμετοχή τους στις κοινωνικές πρακτικές και συλλογικές διεργασίες να μετασχηματιστούν σε σχολικές γνώσεις. Στη συνέχεια, εξετάσαμε πως οι θεωρήσεις που επικρατούν στο χώρο του σχολείου για τη μαθηματική γνώση, υπηρετούνται από συγκεκριμένες πρακτικές οι οποίες και διαμορφώνουν το υποκείμενο πλαίσιο για την κατασκευή και τη ρύθμιση της υποκειμενικότητας του παιδιού στη διαδικασία της σημασιοδότησης. Εξετάσμαε τα νοήματα σε μαθητές των Α' και Β' τάξεων του δημοτικού σχολείου σε υπολογισμούς με διακριτά αντικείμενα αλλά και με το μοντέλο της αριθμογραμμής, στη βάση της παιδαγωγικής θεώρησης του Vygotsky, με τη μέθοδο της κριτικής ανάλυσης λόγου, όπως προτείνεται από την Valery Walkerdine
description: At the present study we've benn searching the meaning of arithmacy and measurement in a socialcultural environmnet in discourses and social practice. We've tried to see under which circumstances the knowledge that the children proccess from the participation in social practices cuold transcorm into typical mathematic knowledge. Moreover, we've investigated how the theories and practices of dicourses that dominate in school, construct the subjectivity of children in the progress of signification. We did the research in students aged 6-7 of primary school in counting with discrete objects as well as with the model of number line sequence, based o Vygotsky's theory with the method of discource analysis, due to Valery Walkerdin's advice
Modeling multidimensional effects in the propagation of radiative shocks
Creators: name: Leygnac, Sébastien
name: Boireau, Laurent
name: Michaut, Claire
name: Lanz, Thierry
name: Stehlé, Chantal
name: Clique, Christine
name: Bouquet, Serge
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Radiative shocks (also called supercritical shocks) are high Mach number shock waves that photoionize the medium ahead of the shock front and give rise to a radiative precursor. They are generated in the laboratory using high-energy or high-power lasers and are frequently present in a wide range of astronomical objects. Their modelisation in one dimension has been the subject of numerous studies, but generalization to three dimensions is not straightforward. We calculate analyticaly the absorption of radiation in a grey uniform cylinder and show how it decreases with chi R, the product of the opacity chi and of the cylinder radius R. Simple formulas, whose validity range increases when chi R diminishes, are derived for the radiation field on the axis of symmetry. Numerical calculations in three dimensions of the radiative energy density, flux and pressure created by a stationary shock wave show how the radiation decreases whith R. Finally, the bidimensional structures of both the precursor and the radiation field are calculated with time-dependent radiation hydrodynamics numerical simulations and the influence of two-dimensional effects on the electron density, the temperature, the shock velocity and the shock geometry are exhibited. These simulations show how the radiative precursor shortens, cools and slows down when R is decreased.
description: Reference of the published article added
Large cardinals and gap-1 morasses
Creators: name: Brooke-Taylor, Andrew D.
name: Friedman, Sy-David
Publisher: name: arXiv
Year: 2008
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 03E35, 03E55

description: We present a new partial order for directly forcing morasses to exist that enjoys a significant homogeneity property. We then use this forcing in a reverse Easton iteration to obtain an extension universe with morasses at every regular uncountable cardinal, while preserving all n-superstrong (0
description: 49 pages
Availability Evaluation of Multi-tenant Service Function Chaining Infrastructures by Multidimensional Universal Generating Function
Creators: name: Di Mauro, Mario
name: Longo, Maurizio
name: Postiglione, Fabio
Publisher: name: arXiv
Year: 2020
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: Performance (cs.PF)
subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: The Network Function Virtualization (NFV) paradigm has been devised as an enabler of next generation network infrastructures by speeding up the provisioning and the composition of novel network services. The latter are implemented via a chain of virtualized network functions, a process known as Service Function Chaining. In this paper, we evaluate the availability of multi-tenant SFC infrastructures, where every network function is modeled as a multi-state system and is shared among different and independent tenants. To this aim, we propose a Universal Generating Function (UGF) approach, suitably extended to handle performance vectors, that we call Multidimensional UGF. This novel methodology is validated in a realistic multi-tenant telecommunication network scenario, where the service chain is composed by the network elements of an IP Multimedia Subsystem implemented via NFV. A steady-state availability evaluation of such an exemplary system is presented and a redundancy optimization problem is solved, so providing the SFC infrastructure which minimizes deployment cost while respecting a given availability requirement.
Cooling of a Compact Star with a LOFF Matter Core
Creators: name: Anglani, Roberto
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Specific heat and neutrino emissivity due to direct URCA processes for quark matter in the color superconductive Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) phase of Quantum-Chromodynamics have been evaluated. The cooling rate of simplified models of compact stars with a LOFF matter core is estimated.
description: 3 pages, 1 figure, to appear in the proceedings of the Helmoltz International Summer School of Theoretical Physics on Dense Matter in Heavy Ion Collisions and Astrophysics, JINR, Dubna, Russia, 21 Aug - 1 Sep 2006
Closed-Form Solutions for a Low-Order System Fast Frequency Response Model
Creators: name: Susanto, Julius
name: Fereidouni, Alireza
name: Mancarella, Pierluigi
name: Sharafi, Dean
Publisher: name: arXiv
Year: 2020
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This paper presents a novel closed-form solution for a low-order system frequency response (SFR) model that is accurate for all time periods and an accompanying approximation for representing primary frequency responses at two different speeds while still maintaining mathematical tractability. This allows for the inclusion of both fast frequency responses (e.g. from battery energy storage systems) and more conventional responses (e.g. from thermal generation) in a single SFR formulation. The closed-form expressions can be efficiently used in applications that use the SFR model such as frequency stability studies and security-constrained unit commitment (SCUC) studies.
A closer look at the indications of q-generalized Central Limit Theorem behavior in quasi-stationary states of the HMF model
Creators: name: Pluchino, A.
name: Rapisarda, A.
name: Tsallis, C.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Astrophysics (astro-ph)
subject: Nuclear Theory (nucl-th)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: We give a closer look at the Central Limit Theorem (CLT) behavior in quasi-stationary states of the Hamiltonian Mean Field model, a paradigmatic one for long-range-interacting classical many-body systems. We present new calculations which show that, following their time evolution, we can observe and classify three kinds of long-standing quasi-stationary states (QSS) with different correlations. The frequency of occurrence of each class depends on the size of the system. The different microsocopic nature of the QSS leads to different dynamical correlations and therefore to different results for the observed CLT behavior.
description: 11 pages, 8 figures. Text and figures added, Physica A in press
CP violation with GeV-scale Majorana neutrino in $Λ_b\to(Λ_c^+, p^+)π^+μ^-μ^-$ decays
Creators: name: Das, Diganta
name: Das, Jaydeb
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We explore the possibility of CP violation in baryonic $Λ_b\to(Λ_c^+, p^+)π^+μ^-μ^-$ decays which are mediated by two Majorana sterile neutrino and are $|ΔL|=2$ lepton number violating processes. Appreciable CP asymmetry can be obtained if there are two on-shell Majorana neutrinos that are quasi-degenerate in mass with the mass difference of the order of average decay widths. We find that given the present constraints on the heavy to light mixing element $|V_{μN}|$, the $Λ_b\to p^+π^+μ^-μ^-$ and $Λ_b\to Λ_c^+π^+μ^-μ^-$ decay rates are suppressed but could be within the experimental reach at the LHC. If searches of the modes are performed, then experimental limits on the rates can be translated to constraints on the Majorana neutrino mass $m_N$ and heavy to light mixing element squared $|V_{μN}|^2$. We show that the constraints on the $(m_N, |V_{μN}|^2)$ parameter space coming from the $|ΔL| = 2$ baryonic decays are complementary to the bounds coming from other processes.
description: 21 pages, 4 figures
Scratch-induced surface microstructures on the deformed surface of Al-Cu-Fe icosahedral quasicrystals
Creators: name: Wu, J. S
name: Brien, Valerie
name: Brunet, P.
name: Dong, C.
name: Dubois, J. -M
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations of sintered Al-Cu-Fe icosahedral quasicrystal (IQC) have been carried out to understand the origin of some ductility previously noticed within tracks produced by standard tribological scratch tests. Transformation of the icosahedral phase to a modulated structure is shown and a transformation of the IQC to a bcc phase has been found beneath the tracks. Twins and dislocations have also been observed.
Mutual feedback between star formation and nuclear activity
Creators: name: Granato, Gian Luigi
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In this invited contribution I review the justifications for the attempts, currently very popular, to include in semi-analytic models of galaxy formation prescriptions to describe the mutual link between the star formation and nuclear activity in galaxies, which has been for surprisingly long time neglected.
description: Review in the Proceedings of the IAU Symposium 235, 2006, Eds F. Combes & J. Palous. 4 pages
Persistent currents in a Bose-Einstein condensate in the presence of disorder
Creators: name: Ogren, M.
name: Kavoulakis, G. M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We examine bosonic atoms that are confined in a toroidal, quasi-one-dimensional trap, subjected to a random potential. The resulting inhomogeneous atomic density is smoothened for sufficiently strong, repulsive interatomic interactions. Statistical analysis of our simulations show that the gas supports persistent currents, which become more fragile due to the disorder.
description: 5 pages, RevTex, 3 figures, revised version, to appear in JLTP
Two young planetary systems around field stars with ages between 20-320 Myr from TESS
Creators: name: Zhou, George
name: Quinn, Samuel N.
name: Irwin, Jonathan
name: Huang, Chelsea X.
name: Collins, Karen A.
name: Bouma, Luke G.
name: Khan, Lamisha
name: Landrigan, Anaka
name: Vanderburg, Andrew M.
name: Rodriguez, Joseph E.
name: Latham, David W.
name: Torres, Guillermo
name: Douglas, Stephanie T.
name: Bieryla, Allyson
name: Esquerdo, Gilbert A.
name: Berlind, Perry
name: Calkins, Michael L.
name: Buchhave, Lars A.
name: Charbonneau, David
name: Collins, Kevin I.
name: Kielkopf, John F.
name: Jensen, Eric L. N.
name: Tan, Thiam-Guan
name: Hart, Rhodes
name: Carter, Brad
name: Stockdale, Christopher
name: Ziegler, Carl
name: Law, Nicholas
name: Mann, Andrew W.
name: Howell, Steve B.
name: Matson, Rachel A.
name: Scott, Nicholas J.
name: Furlan, Elise
name: White, Russel J.
name: Hellier, Coel
name: Anderson, David R.
name: West, Richard G.
name: Ricker, George
name: Vanderspek, Roland
name: Seager, Sara
name: Jenkins, Jon M.
name: Winn, Joshua N.
name: Mireles, Ismael
name: Rowden, Pamela
name: Yahalomi, Daniel A.
name: Wohler, Bill
name: Brasseur, Clara. E.
name: Daylan, Tansu
name: Coloń, Knicole D.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Planets around young stars trace the early evolution of planetary systems. We report the discovery and validation of two planetary systems with ages $\lesssim 300$ Myr from observations by the Transiting Exoplanet Survey Satellite. TOI-251 is a 40-320 Myr old G star hosting a 2.74 +0.18/-0.18 REarth mini-Neptune with a 4.94 day period. TOI-942 is a 20-160 Myr old K star hosting a system of inflated Neptune-sized planets, with TOI-942b orbiting with a period of 4.32 days, with a radius of 4.81 +0.20/-0.20 REarth, and TOI-942c orbiting in a period of 10.16 days with a radius of 5.79 +0.19/-0.18 REarth. Though we cannot place either host star into a known stellar association or cluster, we can estimate their ages via their photometric and spectroscopic properties. Both stars exhibit significant photometric variability due to spot modulation, with measured rotation periods of $\sim 3.5$ days. These stars also exhibit significant chromospheric activity, with age estimates from the chromospheric calcium emission lines and X-ray fluxes matching that estimated from gyrochronology. Both stars also exhibit significant lithium absorption, similar in equivalent width to well-characterized young cluster members. TESS has the potential to deliver a population of young planet-bearing field stars, contributing significantly to tracing the properties of planets as a function of their age.
description: Accepted for publication in AJ
Η εξωτερική πολιτική της Βουλγαρίας και οι ελληνοβουλγαρικές σχέσεις κατά την περίοδο διακυβέρνησης του Αλέξανδρου Σταμπολίσκι
Creators: name: Φαρμάκης, Γεώργιος Κωνσταντίνου
Publisher: name: Aristotle University of Thessaloniki
Year: 2007
Subjects: Σταμπολίσκι
Βουλγαρία
Πολιτική
ΒΑΛΕ (Βουλγαρική Αγροτική Λαϊκή Ενωση)
Μειονότητες
Staboliski
Bulgaria
Policy
BANU (Bulgarian Agrarian National Union)
Western Thrace
Minorities

description: Η εξωτερική πολιτική της Βουλγαρίας στα πρώτα χρόνια μετά τον Α' Παγκόσμιο Πόλεμο ήταν προϊόν των γεωστρατηγικών συνθηκών που είχαν δημιουργηθεί στην Ευρώπη αλλά και των προσωπικών πεποιθήσεων του Πρωθυπουργού Σταμπολίσκι.Η νέα πολιτική κατεύθυνση όριζε την αποκατάσταση σχέσεων καλής γειτονίας με τα όμορα Βαλκανικά κράτη και την αναβάθμιση του διεθνούς κύρους της χώρας. Ακολουθώντας ρεαλιστική πολιτική, η Βουλγαρία παραιτήθηκε από όλες τις εδαφικές αξιώσεις απέναντι στις Βαλκανικές χώρες, πλην της Ελλάδος καθώς συνέχιζε να επιδιώκει την επανάκτηση της Δυτικής Θράκης. Αυτές οι βουλγαρικές φιλοδοξίες αλλά και το μειονοτικό ζήτημα στοιχείωναν τις ελληνοβουλγαρικές σχέσεις τα πρώτα χρόνια μετά τον πόλεμο
description: Bulgaria's foreign policy during the first years after World War I derived from the geostrategic conditions that had been created in Europe and from the personal convictions of the Prime Minister Staboliski. The new political course involved the restoration of the good neighborhooding relations with the balkan countries and the increase of the country's international prestige.Following realistic policy Bulgaria renounced all her territorial demands against every balkan country, except for Greece, as it did not cease to pursue the reoccupation of the Western Thrace. Those ambitions and moreover the minorities problem were haunting the greek-bulgarian relations during the first years after the war
Angular distribution measurement of atoms evaporated from a resistive oven applied to ion beam production
Creators: name: Leduc, A.
name: Thuillier, T.
name: Maunoury, L.
name: Bajeat, O.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Accelerator Physics (physics.acc-ph)
subject: FOS: Physical sciences

description: A low temperature oven has been developed to produce calcium beam with Electron Cyclotron Resonance Ion Source (ECRIS). The atom flux from the oven has been studied experimentally as a function of the temperature and the angle of emission by means of a quartz microbalance. The absolute flux measurement permitted to derive Antoine's coefficient for the calcium sample used : A=8.98$\pm$ 0.07 and B=7787$\pm$ 110 in standard unit. The angular FWHM of the atom flux distribution is found to be 53.7°$\pm$7.3 at 848K, temperature at which the gas behaviour is non collisional. The atom flux hysteresis observed experimentally in several laboratories is explained as follows: at first calcium heating, the evaporation comes from the sample only, resulting in a small evaporation rate. once a full calcium layer has formed on the crucible refractory wall, the calcium evaporation surface includes the crucible's enhancing dramatically the evaporation rate for a given temperature. A Monte-Carlo code, developed to reproduce and investigate the oven behaviour as a function of temperature is presented. A discussion on the gas regime in the oven is proposed as a function of its temperature. A fair agreement between experiment and simulation is found.
description: 16 pages, 11 figures
Segmentation and Analysis of a Sketched Truss Frame Using Morphological Image Processing Techniques
Creators: name: Kamari, Mirsalar
name: Gunes, Oguz
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: Image and Video Processing (eess.IV)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Development of computational tools to analyze and assess the building capacities has had a major impact in civil engineering. The interaction with the structural software packages is becoming easier and the modeling tools are becoming smarter by automating the users role during their interaction with the software. One of the difficulties and the most time consuming steps involved in the structural modeling is defining the geometry of the structure to provide the analysis. This paper is dedicated to the development of a methodology to automate analysis of a hand sketched or computer generated truss frame drawn on a piece of paper. First, we focus on the segmentation methodologies for hand sketched truss components using the morphological image processing techniques, and then we provide a real time analysis of the truss. We visualize and augment the results on the input image to facilitate the public understanding of the truss geometry and internal forces. MATLAB is used as the programming language for the image processing purposes, and the truss is analyzed using Sap2000 API to integrate with MATLAB to provide a convenient structural analysis. This paper highlights the potential of the automation of the structural analysis using image processing to quickly assess the efficiency of structural systems. Further development of this framework is likely to revolutionize the way that structures are modeled and analyzed.
Μιχαήλ Μπακούνιν: η αναρχική θεωρία και η διαμάχη του με τους μαρξιστές
Creators: name: Γουλής, Δημήτριος Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2007
Subjects: Μιχαήλ Μπακούνιν
Καρλ Μαρξ
Αναρχία
Κράτος-κρατισμός
Μαρξισμός
Δικτατορία του προλεταριάτου
Michael Bacounin
Carl Marx
Anarchy
State-statism?
Marxism
The proletariat's dictatorship

description: Στο πρώτο μέρος της εργασίας παραθέτονται κάποια ιστορικά-βιογραφικά στοιχεία για τη ζωή και τη δράση του αναρχικού Μ. Μπακούνιν. Εν συνεχεία, μέσα από τα κύρια έργα του παρουσιάζονται οι βασικές θέσεις του για την κοινωνία, την εκμετάλλευση, την αναρχία, την επανάσταση και την ελευθερία.Το τρίτο μέρος είναι αφιερωμένο στη διαμάχη του Μπακούνιν με το Μαρξ και τους οπαδούς του, αρχίζοντας από τη σύγκρουση στο συνέδριος της 1ης διεθνούς στη Βασιλεία. Επισημαίνονται οι διαφορετικές θεωρήσεις για το άτομο και την επανάσταση και απολήγει η εργασία στην παρουσίαση της ιδεολογικής διαμάχης μεταξύ Μπακούνιν και Μαρξ γύρω από το ζήτημα του κράτους και της επαναστατικής δικτατορίας. Στην κριτική του πρώτου, αντιπαρατίθεται οι απόψεις του δεύτερου, όπως παρουσιάζονται σε βασικά έργα του.
description: The first chapter is a short biography of the anarchist M. Bacounin. At the following chapter, there is a presentation of his basic thesis about society, person, revolution, anarchy and freedom.The third chapter is dediacted at the conflict among M. Bacounin and Karl Marx. There is a confrontation between the critic of M. Bacouninc in terms of state, statism and proletariat's dictatorship and the opinions of K. Marx as they appear in some of his basic writings
Electron microscopy study of scratch-induced surface microstructures in an Al-Cu-Fe icosahedral quasicrystal
Creators: name: Wu, J.
name: Brien, Valerie
name: Brunet, P.
name: Dong, C.
name: Dubois, J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Microstructure modifications induced by sliding a WC-Co indenter in scratch tests on the surface of a single phase AlCuFe icosahedral quasicrystal (IQC) was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The scratch track was shown tocomprise many smaller tracks. Dislocations were discovered to emerge from the edges of the smaller scratch tracks. Along a small track where shear stress is concentrated, a phase transition from IQC to a body-centered cubic (b.c.c.) phase with lattice parameter a=0.29 nm was pointed out. A modulated quasicrystal state as well as a deformation twin of IQC were determined in the region beneath the scratch.