cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Evaluating SCAN and r$^2$SCAN meta-GGA functionals for predicting transition temperatures in antiferromagnetic materials
Creators: name: Rezaei, Nafise
name: Alaei, Mojtaba
name: Oganov, Artem R.
Publisher: name: arXiv
Year: 2025
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Recent advancements in exchange-correlation functionals within density functional theory highlight the need for rigorous validation across diverse types of materials properties. In this study, we assess the performance of the newly developed meta-GGA r$^2$SCAN and its predecessor, SCAN, in predicting the Néel transition temperature of antiferromagnetic materials. Our analysis includes 48 magnetic materials, spanning both simple and complex systems. Using DFT, we compute the energies of various magnetic configurations and extract exchange interaction parameters through a least-squares fitting approach. These parameters are then used in classical Monte Carlo simulations to estimate the transition temperatures. Our results demonstrate that both SCAN and r$^2$SCAN greatly outperform standard GGA and GGA+$U$ methods, yielding predictions that closely align with experimental values. The Pearson correlation coefficients for SCAN and r$^2$SCAN are 0.97 and 0.98, respectively, when compared to experimental transition temperatures. Additionally, we calculate the energy differences between antiferromagnetic and ferromagnetic configurations to assess the performance of the hybrid HSE06 functional. We found that the HSE06 functional underestimates transition temperatures compared to the meta-GGA functionals and experimental values.
Angular momentum of the physical electron
Creators: name: Stewart, A. M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The angular momentum of the physical electron, modelled as a Dirac fermion coupled to the electromagnetic field, is found to be hbar/2, the same as that of a bare Dirac fermion and independent of the size of the electric charge.
description: revision, 3 pages pdf
Coulomb blockade of Cooper pair tunneling and parity effects in the Cooper pair transistor
Creators: name: Corlevi, S.
name: Guichard, W.
name: Hekking, F. W. J.
name: Haviland, D. B.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We have measured the Cooper Pair Transistor (CPT) in a tunable electromagnetic environment consisting of four one-dimensional SQUID arrays. The transport properties of the CPT in the high impedance limit, Z_env>>R_Q=6.45~kΩ, are studied for different ratios of the Josephson coupling energy to the charging energy. As the impedance of the environment is increased, the current-voltage characteristic (IVC) of the CPT develops a Coulomb blockade of Cooper pair tunneling and the measured IVCs agree qualitatively with a theory based on quasicharge dynamics for a CPT. Increasing the impedance of the environment induces a transition in the modulation of the IVC with the gate charge from e-periodic to 2e-periodic.
Publishable Summary for 18NRM04 Heroes Determining new uncertainty requirements for increasingly stringent legislative HCl industrial emission limits
Creators: name: Coleman, Marc
Publisher: name: Zenodo
Year: 2019
Subjects: HCl Standard Reference Method Air Quality Task Force Emissions automated methods for measuring emissions

description: The HCl Standard Reference Method (SRM, EN 1911), which is legislatively required for measuring industrial emissions, is unable to meet uncertainty requirements being brought in via Best Available Techniques (BAT) Conclusions documents (which set permit conditions for regulated industrial processes). This puts at risk the new regulatory framework and the ability of national regulators to carry out enforcement interventions. The project will address these issues by recommending uncertainty requirements for extending the application of the SRM with an associated underpinning evidence base; and providing an evidence base of the performance of portable optical technologies with a view to replace the SRM in the longer term.
Η αμφίσημη σχέση θεωρίας και πράξης: μια συγκριτική μελέτη των αριστοτελικών και των χαϊντεγκεριανών παραδόσεων
Creators: name: Γραμματικόπουλος, Ευάγγελος Ευσταθίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: Πράξη
Θεωρία
Heidegger
Αριστοτέλης
Φρόνηση
Σοφία
Praxis
Theory
Aristotle
Phronesis
Sophia

description: Η παρούσα μελέτη αποτελεί μια απόπειρα εξέτασης της σχέσης μεταξύ δύο θεμελιωδών ανθρώπινων δραστηριοτήτων: της θεωρίας και της πράξης. Αυτή η σχέση θα ειδωθεί υπό το πρίσμα της σκέψης δύο μεγάλων φιλοσόφων-δασκάλων: του Αριστοτέλη και του Martin Heidegger. Το σημείο κλειδί ανάμεσά τους είναι η πρακτική φιλόσοφία του Αριστοτέλη και ο τρόπος με τον οποίον ο Heidegger την αναμορφώνει και την αφομοιώνει στο δικό του φιλοσοφικό σύστημα, διαμέσου της εξελικτικής πορείας στην σκέψη του που θα οδηγήσει στο Είναι και Χρόνος. Ποιο είναι όμως το περιεχόμενο που θα λάβει τελικά η πράξη εντός του χαϊντεγκεριανού πλαισίου; Ποια η γνήσια σχέση της με την αριστοτελική θεωρίαν; Η απάντηση στα ως άνω ερωτήματα θα επιχειρηθεί να δοθεί εντοπίζοντας τα βασικά χαρακτηριστικά που κατέχουν η θεωρία και η πράξη μέσα σε επιλεγμένα συγγράμματα του Αριστοτέλη (Ηθικά Νικομάχεια, Μετά τα Φυσικά Α΄, Περί Ψυχής) και του πρώιμου Heidegger (Φαινομενολογικές ερμηνείες στον Αριστοτέλη, Πλάτων: Σοφιστής, Είναι και Χρόνος). Η εξέταση της απόπειρας του Heidegger να προβεί σε μια παραβίαση της πλήρους διάκρισης θεωρίας και πράξης (ή της ισόρροπής της, μεταξύ σοφίας και φρόνησης) και να αναμετρηθεί με την ίδια την ισχύ της αριστοτελικής θέσης μας ωθεί σε μια επαναδιερεύνηση της μορφής που λαμβάνει η ως άνω σχέση εντός της ανθρώπινης υπόστασης.
description: The current study is in an attempt to examine the relationship between two fundamental human activities: theory and praxis. This relationship will be seen in the light of the thought of two major philosophers: Aristotle and Martin Heidegger. The point of contact between them is the practical philosophy of Aristotle and the way in which Heidegger reforms it and assimilates it into his own system through the evolutionary process of his thought that will result in Being and Time. But what is the content that will eventually take praxis within the heideggerian framework? What is its genuine affinity with the Aristotelian θεωρία; The answer to these questions will be attempted by identifying key features that theory and praxis hold in selected writings of Aristotle (Nicomachean Ethics, Metaphysics A΄, De Anima) and early Heidegger (Phenomenological interpretations in connection with Aristotle, Plato: Sophist, Being and time). The examination of Heidegger's attempt to violate the distinction between theory and praxis (or between sophia and phronesis) and to compete with the very force of Aristotelian position leads us to reconsider the form that this relationship takes in human being.
Αλλεργική ρινίτιδα: εκτίμηση ποιότητας ζωής και αποτελεσματικότητας της θεραπείας:
Creators: name: Μάλλιαρη, Χαρίκλεια Κωνσταντίνου
Publisher: name: Aristotle University of Thessaloniki
Year: 2011
Subjects: αλλεργική ρινίτις
ποιότητα ζωής
θεραπεία
allergic rhinitis
quality of life
therapy

description: Η αλλεργική ρινίτιδα (ΑΡ) είναι μια κοινή πάθηση, της οποίας ο επιπολασμός φαίνεται να αυξάνεται παγκοσμίως τα τελευταία χρόνια. Παρόλο που δεν αποτελεί κατάσταση απειλητική για τη ζωή, παράλληλα με τα άμεσα συμπτώματα που προκαλούνται στο πάσχον όργανο, μπορεί να οδηγήσει σε νοητικές διαταραχές, αποδιοργάνωση της κοινωνικής δραστηριότητας και ανικανότητα να λειτουργήσει ο ασθενής στην καθημερινότητά του έχοντας ως τελικό αποτέλεσμα τη μειωμένη ποιότητα ζωής (QoL). Τελικά εμφανίζει και σημαντική επίπτωση στη δημόσια υγεία και την οικονομία. Παρουσιάζουμε τα αποτελέσματα από την παρακολούθηση 56 ασθενών που παραπέμφθηκαν σε ειδικό ρινολογικό ιατρείο με μέτρια/σοβαρή ρινίτιδα η οποία και αντιμετωπίστηκε με φαρμακευτική αγωγή. Καταγράφησαν τα επιδημιολογικά στοιχεία των ασθενών και επεξεργάστηκαν γενικές και ειδικές πληροφορίες για την πάθηση τους. Μελετήθηκε επίσης, μέσω ειδικού ερωτηματολογίου, η ποιότητα ζωής τους πριν και μετά τη θεραπεία και έγιναν συγκρίσεις ανά ομάδες ασθενών.
description: Allergic rhinitis is a common disease presenting with a globally increasing prevalence. Although not a life-threatening situation, it can lead to mental disorders and incapacity of normal functioning in everyday-life leading to a decreased quality of life. As a result, it is a significant burden in public health and the economy. We present the results after monitoring 56 patients with moderate/severe allergic rhinitis that were treated pharmaceutically. General and specific information about the disease was documented as well as epidemiologic data. The quality of life before and after treatment was also studied using a specific questionnaire and comparisons were made in different patient groups.
Παρασκευή και χαρακτηρισμός στερεών διασπορών της δραστικής ουσίας Τιμπολόνης σε πολυμερική μήτρα PVP/PEG400 και PVP/PEG600 με την τεχνική της ανάμιξης τήγματος:
Creators: name: Κουτσίδης, Ιωάννης Αργυρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: Στερεές διασπορές φαρμάκου
Ανάμιξη τήγματος
Πολυμερή
Solid dispersions of drug substance
Melt mixing
Polymers

description: Στην παρούσα εργασία παρασκευάσθηκαν στερεές διασπορές της δραστικής ουσίας Τιμπολόνης σε πολυμερική μήτρα πολυβινυλοπυρρολιδόνης (φορέας) και πολυαιθυλενογλυκόλης (πλαστικοποιητής) με την τεχνική της ανάμιξης τήγματος. Οι μεταβλητές κατά την παρασκευή των δειγμάτων ήταν το μοριακό βάρος της πολυαιθυλενογλυκόλης (400 και 600), η συγκέντρωση της δραστικής ουσίας (5, 10 και 20% β/β), η θερμοκρασία κατεργασίας (130 και 150οC) και ο χρόνος ανάμιξης (5 και 15 λεπτά). Συνολικά παρασκευάστηκαν 24 δείγματα τα οποία αναλύθηκαν με Περίθλαση Ακτίνων Χ (XRD), Φασματοσκοπία Yπερύθρου Mετασχηματισμού Fourier (FTIR), Διαφορική Θερμιδομετρία Σάρωσης (DSC), Ηλεκτρονική Μικροσκοπία Σάρωσης (SEM), ενώ στο τέλος έγινε έλεγχος του ρυθμού απελευθέρωσης της δραστικής ουσίας με την βοήθεια και της Υγρής Χρωματογραφίας Υψηλής Πίεσης (HPLC). Χρήσιμα συμπεράσματα προέκυψαν για την εφαρμογή της τεχνικής ανάμιξης τήγματος, για τη δράση τόσο της πολυαιθυλενογλυκόλης όσο και της Τιμπολόνης ως πλαστικοποιητές, αλλά και για την επίδραση της πολυμερικής μήτρας και των μεταβλητών στο ρυθμό απελευθέρωσης της δραστικής ουσίας.
description: In the present work solid dispersions of the active pharmaceutical ingredient Tibolone in polymeric matrix of polyvinylpyrrolidone (carrier) and polyethylene glycol (plasticizer) were produced with the technique of melt mixing. The variables during the production of the samples were the molecular weight of polyethylene glycol (400 and 600), the concentration of the active pharmaceutical ingredient (5, 10 and 20% w/w), the processing temperature (130 and 150οC) and the mixing time (5 and 15 minutes). Twenty four samples were produced in total which were analyzed with X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Scanning Electron Microscopy (SEM) while at the end a dissolution test analysis were performed using High Pressure Liquid Chromatography (HPLC). Useful conclusions came up concerning the application of the technique of melt mixing, the plasticizing action of polyethylene glycol and Tibolone, and finally the effect of the polymeric matrix and the variables on the dissolution of the active pharmaceutical ingredient.
Preparation and manipulation of a fault-tolerant superconducting qubit
Creators: name: Cholascinski, Mateusz
name: Makhlin, Yuriy
name: Schön, Gerd
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We describe a qubit encoded in continuous quantum variables of an rf superconducting quantum interference device. Since the number of accessible states in the system is infinite, we may protect its two-dimensional subspace from small errors introduced by the interaction with the environment and during manipulations. We show how to prepare the fault-tolerant state and manipulate the system. The discussed operations suffice to perform quantum computation on the encoded state, syndrome extraction, and quantum error correction. We also comment on the physical sources of errors and possible imperfections while manipulating the system.
description: Typo corrected, title changed as suggested by the editors of Phys. Rev. B, references added
Systematic risk assessment of self-supply systems in households: a case study of Asaba in Nigeria
Creators: name: Akpovi, Angela
Publisher: name: Loughborough University
Year: 2021
Subjects: classificationCode: 339999
subject: Other built environment and design not elsewhere classified

description: In many cities where access to formal water supply system is inadequate, people depend on Self-supply for household domestic needs and drinking. Self-supply describes a system whereby individuals provide water for their households using personal resources and affordable technology. Self-supply is not usually recognised by government authorities, and the water is often consumed unregulated and untreated. Without any form of prior water treatment, there is a high risk of contracting water borne diseases and possible death from drinking contaminated water. Asaba metropolis in Nigeria, is one of such cities where Self-supply is the major source of domestic water supply through borehole technology. This thesis has undertaken a risk assessment of Self-supply borehole water in households and recommends strategies to reduce risks using the Self-Supply Continuous Improvement Plan (SCIP). The SCIP presents a systematic risk assessment strategy designed and adapted from the World Health Organisation’s Water Safety Planning for Small community water supplies. Through the SCIP, the research was designed, and the data collected and analysed. The findings reveal that more than half of surveyed boreholes were rated as high and medium risk due to their proximity to onsite septic tanks and the presence of other environmental contaminants. The focus group discussions revealed the effect on gender. Men in their role as Self-supply water providers are overburdened with the financial obligation of providing water for their households and its safe management. As the main users, women expressed feelings of frustration, annoyance, and anxiety due to unreliability and inconsistencies experienced in the use of household Self-supply. Considering the source to the point-of-use approach of Water Safety Plans, and the unique household characteristics of households in Asaba, households are challenged by inadequate hygienic standards, poor siting conditions of Self-supply boreholes, and lack of government support for households. This research suggests that households can take the lead ahead of government in risk assessment to achieve safe water as a starting point. This research further suggests that the government departments for water supply monitoring in urban areas in Asaba should have the foremost responsibility in supporting private households in monitoring and implementing risk assessment strategies in Self-supply systems.
Exact Solution to Ideal Chain with Fixed Angular Momentum
Creators: name: Deutsch, J. M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The statistical mechanics of a non-interacting polymer chain in the limit of a large number of monomers is considered when the total angular momentum, L, is fixed. The radius of gyration for a ring polymer in this situation is derived exactly in closed form by functional integration techniques. Even when L = 0 the radius of gyration differs from that of a random walk by a prefactor of order unity. The dependence on L is discussed qualitatively and the large L limit can be understood by physical arguments.
description: 9 pages, 2 figures
Φυσικογεωγραφικά και Ιζηματολογικά χαρακτηριστικά του ακρωτηρίου Μύτικας Επανομής, Ν. Θεσσαλονίκης:
Creators: name: Κίρκου, Στέλλα Γεωργίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: Επίπεδο ακρωτήριο
Γεωμορφολογία
Θίνες
Λιμνοθάλασσα
Ηλεκτρικές τομογραφίες
Ιζηματολογία
Επανομή
Cuspate Foreland
Geomorphology
Dunes
Lagoon
ERT (Electrical Resistivity Tomography)
Sedimentology
Epanomi

description: Το επίπεδο ακρωτήριο «Μύτικας» που βρίσκεται στην Επανομή, στο Νομό Θεσσαλονίκης, αποτελεί ένα πλούσιο οικοσύστημα. Έχει τριγωνικό ανάπτυγμα και οριοθετείται από δύο χείμαρρους. Περιέχει διαφόρων ειδών θίνες, οι οποίες καταλαμβάνουν μία εκτεταμένη έκταση εκατέρωθεν αυτού του τριγώνου. Στο εσωτερικό του περιέχει μία λιμνοθάλασσα, η οποία αποτελεί καταφύγιο για αρκετά είδη πτηνών. Στο πλήρες ανάπτυγμα της η λιμνοθάλασσα έχει περίμετρο 5,5 Km. Οι ζώνες επαύξησης του ακρωτηρίου βρίσκονται στη Νότια πλευρά του και ο κύριος άνεμος που επικρατεί στην περιοχή είναι ο βόρειος. Οι ιζηματολογικες αναλύσεις στα επιφανειακά ιζήματα της περιοχής δείχνουν αδρόκοκκη άμμο, ενώ στο εσωτερικό της λιμνοθάλασσας η μέθοδος του σιφωνίου δείχνει αμμούχο ιλύ. Με τη βοήθεια των ηλεκτρικών τομογραφιών, το επίπεδο ακρωτήριο, πιθανά, χρονολογείται στα 12000 yBP και η λιμνοθάλασσα στα 8000 yBP.
description: The Cuspate Foreland “Mitikas” of Epanomi, prefecture area of Thessaloniki, is a wealthy ecosystem. It has a triangle shape and demarcated of two streams. It has a variety of dunes, which are extent to both sides of the triangle. In the inland of this cuspate foreland there is a lagoon, which is the home for many kinds of birds. The fool expansion of lagoon has 5,5 Km perimeter. Accretion zones are found to the South side of the cuspate foreland and the main wind is North wind. Sedimentologycal analysis of the surface sediment gives grit sand and the lagoons pipette analysis gives sandy mud. The chronology of this cuspate foreland probably is 12000yBP and the lagoons’ age is 8000 yBP. This result came up from the ERT, which took place in the area.
Bergman-Bourgain-Brezis-type Inequality
Creators: name: Da Lio, Francesca
name: Rivière, Tristan
name: Wettstein, Jerome
Publisher: name: arXiv
Year: 2020
Subjects: subject: Analysis of PDEs (math.AP)
subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 26A33, 32A10, 32A35, 32A36

description: In this note, we prove a fractional version in $1$-D of the Bourgain-Brezis inequality \cite{bourgain1}. We show that such an inequality is equivalent to the fact that a holomorphic function $f\colon\D\to\C$ belongs to the Bergman space ${\mathcal{A}}^2(\D)$, namely $f\in L^2(\D)$, if and only if $$\|f\|_{ L^1+ {H}^{-1/2}(S^1)}:=\limsup_{r\to 1^-}\|f(re^{iθ})\|_{ L^1+ {H}^{-1/2}(S^1)}
Decentralized Multi-Antenna Architectures with Unitary Constraints
Creators: name: Alegría, Juan Vidal
name: Edfors, Ove
Publisher: name: arXiv
Year: 2025
Subjects: subject: Signal Processing (eess.SP)
subject: Information Theory (cs.IT)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: The increase in the number of base station (BS) antennas calls for efficient solutions to deal with the increased interconnection bandwidth and processing complexity of traditional centralized approaches. Decentralized approaches are thus gaining momentum, since they achieve important reductions in data/processing volume by preprocessing the received signals before forwarding them to a central node. The WAX framework offers a general description of decentralized architectures with arbitrary interplay between interconnection bandwidth and decentralized processing complexity, but the applicability of this framework has only been studied assuming unrestricted baseband processing. We consider an adaptation of the WAX framework where the decentralized processing has unitary restriction, which allows for energy-efficient implementations based on reconfigurable impedance networks at the cost of some performance loss. Moreover, we propose an effective method to minimize the performance gap with respect to centralized processing. The previous method gives a first step towards characterizing the information-lossless trade-off between interconnection bandwidth and processing complexity in decentralized architectures with unitary constraints.
description: 5 pages, 1 figure (3 subfigures). This work has been presented at the Asilomar Conference on Signals, Systems, and Computers. Copyright information may be affected upon publication in the IEEE Proceedings
Το πρόβλημα της ουδετερότητας στη σχολική θρησκευτική αγωγή: ψυχολογική – παιδαγωγική διερεύνηση
Creators: name: Αλεξιάδου, Μαρία Θωμά
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: Ουδετερότητα
Σχολική θρησκευτική αγωγή
Ψυχοπαιδαγωγική θεώρηση
Neutrality
School religious education
Psychological – pedagogical investigation

description: Στην παρούσα εργασία γίνεται μια προσπάθεια να εξεταστεί το κατά πόσο ένα ουδέτερο μοντέλο διδασκαλίας των Θρησκευτικών είναι λειτουργικό. Η μελέτη πραγματοποιείται υπό το πρίσμα των ψυχολογικών θεωριών της γνωστικής ανάπτυξης του παιδιού, καθώς και των αρχών μάθησης και διδασκαλίας. Το συμπέρασμα στο οποίο καταλήγουμε είναι ότι ένα ουδετερόθρησκο μοντέλο διδασκαλίας συναντά αρκετές δυσκολίες κατά την εφαρμογή του στην υποχρεωτική εκπαίδευση.
description: This thesis is an attempt is made to examine whether a neutral model of religious education is functional. The study carried out in the light of psychological theories of cognitive development of children and the principles of learning and teaching. The conclusion reached is that a neutral model of religious education meets several difficulties in the implementation of compulsory education.
Spontaneous decay of an excited atom placed near a rectangular plate
Creators: name: Nguyen, Tuan Anh
name: Dung, Ho Trung
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Using the Born expansion of the Green tensor, we consider the spontaneous decay rate of an excited atom placed in the vicinity of a rectangular plate. We discuss the limitations of the commonly used simplifying assumption that the plate extends to infinity in the lateral directions and examine the effects of the atomic dipole moment orientation, atomic position, and plate boundary and thickness on the atomic decay rate. In particular, it is shown that in the boundary region, the spontaneous decay rate can be strongly modified.
description: 5 pages, 5 figures
Μελέτη εξέλιξης και ανάλυσης απόψεων από πηγές κοινωνικού Ιστού:
Creators: name: Ράμμου, Μαρία Αθανασίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: Επικρατούσα θεματολογία
Αποτύπωση συναισθήματος
Σημασιολογικός ιστός
Κοινωνικά δίκτυα
Κοινωνικός ιστός
Topic analysis
Opinion mining
Sentiment analysis
Semantic web
Social networks
Twitter

description: Η εξάπλωση των υποδομών και των υπηρεσιών του διαδικτύου και η ακόλουθη επέκταση του αριθμού των χρηστών διαμορφώνει μία παγκόσμια δυναμική, στα πλαίσια της οποίας οι χρήστες είναι σε θέση να ανταλλάσουν πληροφορίες, γνώμες, απόψεις, αλλά ακόμα και να εκφράζουν συναισθήματα δημιουργώντας δεξαμενές πληροφοριών, από τις οποίες δύναται να αντληθούν τόσο οι προβληματισμοί όσο και οι ενασχολήσεις των χρηστών, που στο σύνολό τους εκφράζουν την θεματολογία των κοινωνικών δικτύων. Η εξαγωγή καθώς και η εξέλιξη αυτής της θεματολογίας αποτελεί το αντικείμενο μελέτης των δύο πρώτων σκοπών της παρούσας διπλωματικής εργασίας. Το δεύτερο τμήμα της παρούσας εργασίας, αφορά στον τρίτο σκοπό αυτής και ασχολείται με την εξαγωγή και την μελέτη των συναισθημάτων που εκφράζονται από τους χρήστες στον παγκόσμιο ιστό και συγκεκριμένα στα κοινωνικά δίκτυα. Πηγή άντλησης των δεδομένων για το πειραματικό κομμάτι της παρούσας μελέτης είναι το κοινωνικό δίκτυο του twitter. Το προγραμματιστικό κομμάτι της μελέτης έχει αναπτυχθεί σε γλώσσα προγραμματισμού python.
description: The present intergraded study is developed in three different scientific areas that serve three different but supplementary purposes. The main avocation is the detection of the set of the most frequent used words inside the data sets that are used in the analysis. The second purpose is to define the way that the frequent words are behaved in the timeline and the third purpose is to measure and present the sentiment that the data represent as far as the frequent words are concerned. The data sets are collected from social web sources and more specifically from twitter. The programming part of this study is developed using python.
Exploring conformational energy landscape of glassy disaccharides by CPMAS 13C NMR and DFT/GIAO simulations. II. Enhanced molecular flexibility in amorphous trehalose
Creators: name: Lefort, Ronan
name: Bordat, Patrice
name: Cesaro, Attilio
name: Descamps, Marc
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: This paper deals with the comparative use of the chemical shift surfaces to simulate experimental 13C CPMAS data on amorphous solid state disaccharides, paying particular attention to -1-1 linkage of trehalose, to -1,4 linkage between pyranose rings (lactose) and to linkage implying a furanose ring (sucrose). The combination of molecular mechanics with DFT/GIAO ab-initio methods provides reliable structural information on the conformational distribution in the glass. The results are interpreted in terms of an enhanced flexibility that trehalose experiences in amorphous solid state compared to the other sugars. An attempt to relate this property to the balance between intra- and inter-molecular hydrogen bonding network in the glass is presented.
Static magnetic proximity effects and spin Hall magnetoresistance in Pt/Y$_{3}$Fe$_{5}$O$_{12}$ and inverted Y$_{3}$Fe$_{5}$O$_{12}$/Pt bilayers
Creators: name: Geprägs, Stephan
name: Klewe, Christoph
name: Meyer, Sibylle
name: Graulich, Dominik
name: Schade, Felix
name: Schneider, Marc
name: Francoual, Sonia
name: Collins, Stephen P.
name: Ollefs, Katharina
name: Wilhelm, Fabrice
name: Rogalev, Andrei
name: Joly, Yves
name: Goennenwein, Sebastian T. B.
name: Opel, Matthias
name: Kuschel, Timo
name: Gross, Rudolf
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The magnetic state of heavy metal Pt thin films in proximity to the ferrimagnetic insulator Y$_{3}$Fe$_{5}$O$_{12}$ has been investigated systematically by means of x-ray magnetic circular dichroism and x-ray resonant magnetic reflectivity measurements combined with angle-dependent magnetotransport studies. To reveal intermixing effects as the possible cause for induced magnetic moments in Pt, we compare thin film heterostructures with different order of the layer stacking and different interface properties. For standard Pt layers on Y$_{3}$Fe$_{5}$O$_{12}$ thin films, we do not detect any static magnetic polarization in Pt. These samples show an angle-dependent magnetoresistance behavior, which is consistent with the established spin Hall magnetoresistance. In contrast, for the inverted layer sequence, Y$_{3}$Fe$_{5}$O$_{12}$ thin films grown on Pt layers, Pt displays a finite induced magnetic moment comparable to that of all-metallic Pt/Fe bilayers. This magnetic moment is found to originate from finite intermixing at the Y$_{3}$Fe$_{5}$O$_{12}$/Pt interface. As a consequence, we found a complex angle-dependent magnetoresistance indicating a superposition of the spin Hall and the anisotropic magnetoresistance in these type of samples. Both effects can be disentangled from each other due to their different angle dependence and their characteristic temperature evolution.
The interplay of user preference and precision in different gaze-based interaction methods
Creators: name: Severitt, Björn Rene
name: Sauer, Yannick
name: Neugebauer, Alexander
name: Agarwala, Rajat
name: Castner, Nora
name: Wahl, Siegfried
Publisher: name: arXiv
Year: 2025
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: In this study, we investigated gaze-based interaction methods within a virtual reality game with a visual search task with 52 participants. We compared four different interaction techniques: Selection by dwell time or confirmation of selection by head orientation, nodding or smooth pursuit eye movements. We evaluated both subjective and objective performance metrics, including NASA-TLX for subjective task load as well as time to find the correct targets and points achieved for objective analysis. The results showed significant differences between the interaction methods in terms of NASA TLX dimensions, time to find the right targets, and overall performance scores, suggesting differential effectiveness of gaze-based approaches in improving intuitive system communication. Interestingly, the results revealed gender-specific differences, suggesting interesting implications for the design of gaze-based interaction paradigms that are optimized for different user needs and preferences. These findings could help to develop more customized and effective gaze interaction systems that can improve accessibility and user satisfaction.
On the Nature of the T Tauri Triple System
Creators: name: Beck, Tracy L.
name: Schaefer, G. H.
name: Guilloteau, S.
name: Simon, M.
name: Dutrey, A.
name: Di Folco, E.
name: Chapillon, E.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present a multi-wavelength analysis to reveal the nature of the enigmatic T Tauri triple star system. New optical and infrared measurements are coupled with archival X-ray, UV and mm datasets to show morphologies of disk material and outflow kinematics. A dark lane of obscuring material is seen in silhouette in several emission lines and in model-subtracted ALMA mm continuum dust residuals near the position of T Tau Sa+Sb, revealing the attenuating circumbinary ring around T Tau S. The flux variability of T Tau S is linked in part to the binary orbit; T Tau Sb brightens near orbital apastron as it emerges from behind circumbinary material. Outflow diagnostics confirm that T Tau N powers the blue-shifted western outflow, and the T Tau S binary drives the northwest-southeastern flow. Analysis of the southern outflow shows periodic arcs ejected from the T Tau system. Correlation of these arc locations and tangential kinematics with the orbit timing suggests that launch of the last four southern outflow ejections is contemporaneous with, and perhaps triggered by, the T Tau Sa+Sb binary periastron passage. We present a geometry of the T Tau triple that has the southern components foreground to T Tau N, obscured by a circumbinary ring, with mis-aligned disks and interacting outflows. Particularly, a wind from T Tauri Sa that is perpendicular to its circumstellar disk might interact with the circumbinary material, which may explain conflicting high contrast measurements of the system outflows in the literature. T Tauri is an important laboratory to understand early dynamical processes in young multiple systems. We discuss the historical and future characteristics of the system in this context.
description: Accepted for publication in the Astrophysical Journal
The characteristic polynomial of a multiarrangement
Creators: name: Abe, Takuro
name: Terao, Hiroaki
name: Wakefield, Max
Publisher: name: arXiv
Year: 2006
Subjects: subject: Commutative Algebra (math.AC)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 32S22 (Primary) 14N20, 52C35 (Secondary)

description: Given a multiarrangement of hyperplanes we define a series by sums of the Hilbert series of the derivation modules of the multiarrangement. This series turns out to be a polynomial. Using this polynomial we define the characteristic polynomial of a multiarrangement which generalizes the characteristic polynomial of an arragnement. The characteristic polynomial of an arrangement is a combinatorial invariant, but this generalized characteristic polynomial is not. However, when the multiarrangement is free, we are able to prove the factorization theorem for the characteristic polynomial. The main result is a formula that relates `global' data to `local' data of a multiarrangement given by the coefficients of the respective characteristic polynomials. This result gives a new necessary condition for a multiarrangement to be free. Consequently it provides a simple method to show that a given multiarrangement is not free.
description: 12 pages, 2 figures
Evolutionary Map of the Universe (EMU):Compact radio sources in the SCORPIO field towards the Galactic plane
Creators: name: Riggi, S.
name: Umana, G.
name: Trigilio, C.
name: Cavallaro, F.
name: Ingallinera, A.
name: Leto, P.
name: Bufano, F.
name: Norris, R. P.
name: Hopkins, A. M.
name: Filipović, M. D.
name: Andernach, H.
name: van Loon, J. Th.
name: Michałowski, M. J.
name: Bordiu, C.
name: An, T.
name: Buemi, C.
name: Carretti, E.
name: Collier, J. D.
name: Joseph, T.
name: Koribalski, B. S.
name: Kothes, R.
name: Loru, S.
name: McConnell, D.
name: Pommier, M.
name: Sciacca, E.
name: Schilliró, F.
name: Vitello, F.
name: Warhurst, K.
name: Whiting, M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Machine Learning (stat.ML)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We present observations of a region of the Galactic plane taken during the Early Science Program of the Australian Square Kilometre Array Pathfinder (ASKAP). In this context, we observed the SCORPIO field at 912 MHz with an uncompleted array consisting of 15 commissioned antennas. The resulting map covers a square region of ~40 deg^2, centred on (l, b)=(343.5°, 0.75°), with a synthesized beam of 24"x21" and a background rms noise of 150-200 μJy/beam, increasing to 500-600 μJy/beam close to the Galactic plane. A total of 3963 radio sources were detected and characterized in the field using the CAESAR source finder. We obtained differential source counts in agreement with previously published data after correction for source extraction and characterization uncertainties, estimated from simulated data. The ASKAP positional and flux density scale accuracy were also investigated through comparison with previous surveys (MGPS, NVSS) and additional observations of the SCORPIO field, carried out with ATCA at 2.1 GHz and 10" spatial resolution. These allowed us to obtain a measurement of the spectral index for a subset of the catalogued sources and an estimated fraction of (at least) 8% of resolved sources in the reported catalogue. We cross-matched our catalogued sources with different astronomical databases to search for possible counterparts, finding ~150 associations to known Galactic objects. Finally, we explored a multiparametric approach for classifying previously unreported Galactic sources based on their radio-infrared colors.
description: 31 pages, 15 figures, 15 tables
Gravitational Radiation from Ultra High Energy Cosmic Rays in Models with Large Extra Dimensions
Creators: name: Koch, Ben
name: Drescher, Hans-Joachim
name: Bleicher, Marcus
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The effects of classical gravitational radiation in models with large extra dimensions are investigated for ultra high energy cosmic rays (CRs). The cross sections are implemented into a simulation package (SENECA) for high energy hadron induced CR air showers. We predict that gravitational radiation from quasi-elastic scattering could be observed at incident CR energies above $10^9$ GeV for a setting with more than two extra dimensions. It is further shown that this gravitational energy loss can alter the energy reconstruction for CR energies $E_{\rm CR}\ge 5\cdot 10^9$ GeV.
Arithmetical properties of Multiple Ramanujan sums
Creators: name: Yamasaki, Yoshinori
Publisher: name: arXiv
Year: 2007
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11A25

description: In the present paper, we introduce a multiple Ramanujan sum for arithmetic functions, which gives a multivariable extension of the generalized Ramanujan sum studied by D. R. Anderson and T. M. Apostol. We then find fundamental arithmetic properties of the multiple Ramanujan sum and study several types of Dirichlet series involving the multiple Ramanujan sum. As an application, we evaluate higher-dimensional determinants of higher-dimensional matrices, the entries of which are given by values of the multiple Ramanujan sum.
description: 19 pages
STM Studies of TbTe3: Evidence for a fully Incommensurate Charge Density Wave
Creators: name: Fang, A.
name: Ru, N.
name: Fisher, I. R.
name: Kapitulnik, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We observe unidirectional charge density wave ordering on the cleaved surface of TbTe3 with a Scanning Tunneling Microscope at ~6 K. The modulation wave-vector q_{CDW} as determined by Fourier analysis is 0.71 +/- 0.02 * 2 pi/c. (Where c is one edge of the in-plane 3D unit cell.) Images at different tip-sample voltages show the unit cell doubling effects of dimerization and the layer below. Our results agree with bulk X-ray measurements, with the addition of ~(1/3) * 2 pi/a ordering perpendicular to the CDW. Our analysis indicates that the CDW is incommensurate.
description: 4 pages, 4 figures
The Word file of the supporting information for the paper "Free-Standing Carbon Nanotube Embroidered Graphene Film Electrode Array for Stable Neural Interfacing" published on Nano Letters.
Creators: name: Gao, Lei
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 400309
subject: Neural engineering

description: The Word file of the supporting information for the paper "Free-Standing Carbon Nanotube Embroidered Graphene Film Electrode Array for Stable Neural Interfacing" published on Nano Letters.
Η έννοια της ηγεσίας στις ελληνικές επιχειρήσεις και η επίδραση της οικονομικής κρίσης σε αυτή:
Creators: name: Καρακικέ, Βασιλική Δημητρίου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: επιχειρησιακή κρίση
ετοιμότητα κρίσης
προγράμματα ανάπτυξης ηγέτη
crisis leadership
crisis preparedness
leader development programs

description: Σκοπός της παρούσας εργασίας είναι να εξετάσει την έννοια της ηγεσίας στις ελληνικές επιχειρήσεις. Πιο συγκεκριμένα, διερευνούνται τα ατομικά χαρακτηριστικά, το στυλ ηγεσίας και τα προγράμματα ανάπτυξης ηγεσίας που συσχετίζονται με την αντίληψη ετοιμότητας ενός ηγέτη ως προς την αντιμετώπιση μιας επιχειρησιακής κρίσης. Η πρωτοτυπία της έγκειται στον συνδυασμό της εξέτασης των παραπάνω μεταβλητών, καθώς και στην εξέταση των ελληνικών επιχειρήσεων. Η παρούσα έρευνα βασίζεται κυρίως σε βιβλιογραφία σχετική με τα παραπάνω πεδία, ενώ εμπεριέχονται συγκρίσεις των αποτελεσμάτων της με αυτών προηγούμενων σχετικών ερευνών. Η έρευνα διεξήχθη μέσω συνεντεύξεων σε δέκα ηγέτες, υπευθύνους ανθρωπίνου δυναμικού ελληνικών επιχειρήσεων. Αρχικά οι ηγέτες συμπλήρωσαν ερωτηματολόγιο από τις απαντήσεις του οποίου εξήχθησαν τα αποτελέσματα των συσχετίσεων, ενώ ακολούθησε συνέντευξη για να πραγματοποιηθεί μια σε βάθος ανάλυση των ηγετικών τους προφίλ αλλά και των καταστάσεων που επικρατούν στην επιχείρηση στην οποία εργάζονται. Το κυριότερο εύρημα από ακαδημαϊκής πλευρά, είναι ότι οι ηγέτες που χρησιμοποιούν το μετασχηματιστικό στυλ ηγεσίας τείνουν να αισθάνονται περισσότερο έτοιμοι να διαχειριστούν ενδεχόμενες επιχειρησιακές κρίσεις. Το αποτέλεσμα αυτό έρχεται σε συμφωνία και με συμπεράσματα πρότερων ερευνών. Για τους ανθρώπους του επιχειρηματικού χώρου, κυριότερο κρίνεται το συμπέρασμα ότι, η συμμετοχή του ηγέτη σε προγράμματα ανάπτυξης ηγετικών δεξιοτήτων αυξάνει την ετοιμότητά του ως προς την αντιμετώπιση επιχειρησιακών κρίσεων.
description: The purpose of this paper is the examination of the correlation between the characteristics of masculinity and characteristics which are considered adequate to face the economic crisis, the leadership style, the perception of a leader for his preparedness to face potential business crises and his participation in programs for the development of leadership skills. The originality lies in the combination of the above measures and the locality of the companies (Greek companies). This work is based mainly on literature related to these fields and the results include comparisons of this study with those of previous investigations. The survey was conducted in ten leaders, human resource managers of Greek firms. After a thorough research we concluded in an important finding for academics, under which the leaders who use transformational leadership style tend to feel more prepared to manage potential business crises. The result is in agreement with findings following earlier investigations. For people in the business area, the main conclusion is that the (variety) of the leader participation in leadership development programs increases the readiness to face operational crises. These findings confirmed the initial assumptions which are presented bellow.
Revisiting the Cosmological Constant Problem within Quantum Cosmology
Creators: name: Gueorguiev, Vesselin G.
name: Maeder, Andre
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: A new perspective on the Cosmological Constant Problem (CCP) is proposed and discussed within the multiverse approach of Quantum Cosmology. It is assumed that each member of the ensemble of universes has a characteristic scale $a$ that can be used as integration variable in the partition function. An averaged characteristic scale of the ensemble is estimated by using only members that satisfy the Einstein field equations. The averaged characteristic scale is compatible with the Planck length when considering an ensemble of solutions to the Einstein field equations with an effective cosmological constant. The multiverse ensemble is split in Planck-seed universes with vacuum energy density of order one; thus, $ \tildeΛ\approx 8π$ in Planck units and $a$-derivable universes. For~$a$-derivable universe with a characteristic scale of the order of the observed Universe $a\approx 8\times10^{60}$, the cosmological constant $Λ=\tildeΛ/a^{2}$ is in the range $10^{-121}$--$10^{-122}$, which is close in magnitude to the observed value $10^{-123}$. We point out that the smallness of $Λ$ can be viewed to be natural if its value is associated with the entropy of the Universe. This approach to the CCP reconciles the Planck-scale huge vacuum energy--density predicted by QFT considerations, as valid for Planck-seed universes, with the observed small value of the cosmological constant as relevant to an $a$-derivable universe as~observed.
description: 16 pages, no figures
Μέθοδοι, Περιεχόμενο και Διαχείρισή τους για την Εκπαίδευση Καθηγητών Ξένων Γλωσσών στο CALL:
Creators: name: Κοσμίδου, Ελένη Νικoλάου
Publisher: name: Aristotle University of Thessaloniki
Year: 2012
Subjects: επιμόρφωση εκπαιδευτικών
γλωσσική εκπαίδευση
Νέες Τεχνολογίες
language teacher training
in-service courses
CALL

description: Η ανάγκη για επιμόρφωση των εκπαιδευτικών των ξένων γλωσσών στις Τεχνολογίες της Πληροφορίας και των Επικοινωνιών κρίνεται επιτακτική στη σημερινή εποχή. Στην εργασία αυτή ερευνώνται προγράμματα επιμόρφωσης που έλαβαν χώρα στην Ελλάδα, με στόχο την αποτελεσματικότητα των Νέων Τεχνολογιών στη γλωσσική εκπαίδευση, αφού πρώτα γίνει βιβλιογραφική αναφορά σε παρόμοια προγράμματα ανά τον κόσμο. Ειδικότερα, εστιάζεται προσοχή στην αποτελεσματικότητα συγκεκριμένων επιμορφωτικών έργων μέσα από το περιεχόμενο, τη μέθοδο και τη διαχείριση αυτών αναφορικά με τη διάδοση της γνώσης στο CALL.
description: There is an imperative need for language teacher training on ICT nowadays. This dissertation examines in-service training courses that were held in Greece, in order to evaluate the effectiveness of New Technologies in language education. Prior to this research, there is a literature review of similar programs worldwide. More specifically, it focuses on the effectiveness of specific teacher training projects in terms of content, method and distribution regarding the knowledge dissemination on CALL.
Chance Constrained Optimization for Energy Management in Electric Vehicles
Creators: name: Mohagheghi, Erfan
name: Gasso, Joan Gubianes
name: Geletu, Abebe
name: Li, Pu
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics

description: E-powertrain of future electric vehicles could consist of energy generation units (e.g., fuel cells and photovoltaic modules), energy storage systems (e.g., batteries and supercapacitors), energy conversion units (e.g., bidirectional DC/DC converters and DC/AC inverters) and an electric machine, which can work in both generating and motoring modes [1- 6]. An energy management system is responsible to operate the above-mentioned components in a way that the technical constraints are satisfied. This task should be accomplished by solving an optimization problem, which could aim at minimizing the total operation costs [5]. The optimization problem has been widely addressed by deterministic approaches [7], which take into account the forecasted values of active-reactive load profile. However, as shown in Figure 1 (a), it is impossible to accurately forecast the values, meaning that the solutions coming from deterministic approaches could lead to infeasible operations (i.e., constraint violations). Therefore, stochastic optimization approaches [8] should be utilized to fi nd optimal solution strategies while considering uncertain parameters.
Real-Time Dynamic Optimal Power Flow in Electric Vehicles Considering the Lifetime of the Components in the E-Powertrain
Creators: name: Mohagheghi, Erfan
name: Gasso, Joan Gubianes
name: Li, Pu
Publisher: name: arXiv
Year: 2020
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Different types of energy sources (e.g., batteries, supercapacitors, fuel cells) can be utilized in electric vehicles to store and provide energy in the e-powertrain through power electronic devices [1-6]. The lifetime of the components in the e-powertrain depends on their load profile [7,8]. For instance, the lifetime of a battery highly depends on the depth of discharge and the number of charge/discharge cycles [9-13]. The lifetime of an inverter mostly depends on the variations in the active-reactive power passing through it. This means that the expended life cost of the components can be decreased by allocating an optimal share of the total power to each energy source and power electronic device at an optimal time instance. In addition, the driving range of a vehicle can be prolonged by decreasing the energy loss i.e., operating the components in their high-efficiency region. Therefore, it is necessary to perform Optimal Power Flow (OPF) in the operation of the e-powertrain.