cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Linear magnetization dependence and large intrinsic anomalous Hall effect in Fe78Si9B13 metallic glasses
Creators: name: Wu, Weiwei
name: Li, Jinfeng
name: Liao, Zhiyu
name: Jiang, Hongyu
name: Shen, Laiquan
name: Gu, Lin
name: Qiu, Xianggang
name: Yao, Yugui
name: Bai, Haiyang
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The origin of anomalous Hall effect (AHE) in ferromagnetic metallic glasses (MGs) is not yet understood completely. Here, the AHE is explored in Fe78Si9B13 MGs. We find the behavior of resistivity at low temperature seems to be more likely due to structure effect rather than Kondo-type effect. More importantly, we firstly find the primitive experiment anomalous Hall conductivity (σAH) without separation of extrinsic contribution has a linear magnetization (Mz) dependence when temperature is changing, which is another feature of intrinsic mechanism and indicates intrinsic contribution is dominated. Furthermore, the σAH normalized by Mz is independent of longitudinal conductivity (σxx), which shows the characteristic of dissipationless intrinsic mechanism. We suggest the intrinsic contribution can be understood from the density of Berry curvature integrated over occupied energies proposed for aperiodic materials recently, and the linear magnetization dependence can be understood qualitatively from the fluctuations of spin orientation and the proportional relationship between Berry curvature and magnetization. Moreover, based on the recent theory report of topological amorphous metals, we make a prediction that the large intrinsic σAH (616 S/cm) in Fe78Si9B13 MGs implies some topological properties of MGs waiting for further discovery.
Refoulé, F., Geffré, C.-J., Rohier, J.-M., Duquoc, C.: Avenir de la Théologie...
Creators: name: Epting, Friedrich
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 18 Nr. 2 (1969): Ökumenische Rundschau, Band 18, Heft 2
Επιλογή εξωτερικού παρόχου 3PL με τη μέθοδο πολυκριτηριακής ανάλυσης AHP
Creators: name: Λειβαδάρου, Γεωργία
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2020
Subjects: subject: Analytic Hierarchy Process (AHP)
subject: Αξιολόγηση συνεργατών 3PL
subject: Πολυκριτηριακή ανάλυση

description: Η ανάθεση των διαδικασιών Logistics σε εξωτερικούς φορείς ( Third – Party Logistics Providers, 3PL’s ) αποτελεί απόφαση στρατηγικής σημασίας για κάθε επιχείρηση. Μία σωστή επιλογή παρόχου, μπορεί να αποτελέσει το ανταγωνιστικό πλεονέκτημα της εταιρείας και για αυτό το λόγο πρέπει να εξετάζεται εκτενώς πριν την υλοποίηση της συνεργασίας. Στην βιβλιογραφία υπάρχουν πολλές μέθοδοι αξιολόγησης και επιλογής παρόχου με μία από τις πιο διαδεδομένες να είναι η μέθοδος της πολυκριτηριακής ανάλυσης . Σε αυτή την εργασία θα αναφερθούν τα βασικά στοιχεία της πολυκριτηριακής ανάλυσης και πιο συγκεκριμένα της εφαρμογής της μεθόδου Αναλυτικής Ιεράρχησης ( Analytic Hierarchy Process ). Αυτό θα γίνει με τη μελέτη περίπτωσης μίας εταιρείας που δραστηριοποιείται στο κλάδο παραγωγής βιομηχανικών λιπαντικών και επιθυμεί να αναθέσει τις διαδικασίες αποθήκευσης και μεταφοράς προϊόντων σε εξωτερικό πάροχο υπηρεσιών. Για τον σκοπό αυτό, χρησιμοποιείται το λογισμικό Expert Choice, ένα εργαλείο υποστήριξης αποφάσεων βασισμένο στην AHP.
Automated, Cost-effective, and Update-driven App Testing
Creators: name: Ngo, Chanh Duc
name: Pastore, Fabrizio
name: Briand, Lionel
Publisher: name: arXiv
Year: 2020
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: Apps' pervasive role in our society led to the definition of test automation approaches to ensure their dependability. However, state-of-the-art approaches tend to generate large numbers of test inputs and are unlikely to achieve more than 50% method coverage. In this paper, we propose a strategy to achieve significantly higher coverage of the code affected by updates with a much smaller number of test inputs, thus alleviating the test oracle problem. More specifically, we present ATUA, a model-based approach that synthesizes App models with static analysis, integrates a dynamically-refined state abstraction function and combines complementary testing strategies, including (1) coverage of the model structure, (2) coverage of the App code, (3) random exploration, and (4) coverage of dependencies identified through information retrieval. Its model-based strategy enables ATUA to generate a small set of inputs that exercise only the code affected by the updates. In turn, this makes common test oracle solutions more cost-effective as they tend to involve human effort. A large empirical evaluation, conducted with 72 App versions belonging to nine popular Android Apps, has shown that ATUA is more effective and less effort intensive than state-of-the-art approaches when testing App updates.
The environmental dependence of galaxy clustering in the Sloan Digital Sky Survey
Creators: name: Abbas, Ummi
name: Sheth, Ravi K.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: A generic prediction of hierarchical clustering models is that the mass function of dark haloes in dense regions in the Universe should be top-heavy. We provide a novel test of this prediction using a sample of galaxies drawn from the Sloan Digital Sky Survey. To perform the test, we compare measurements of galaxy clustering in dense and underdense regions. We find that galaxies in dense regions cluster significantly more strongly than those in less dense regions. This is true over the entire 0.1--30 Mpc pair separation range for which we can make accurate measurements. We make similar measurements in realistic mock catalogs in which the only environmental effects are those which arise from the predicted correlation between halo mass and environment. We also provide an analytic halo-model based calculation of the effect. Both the mock catalogs and the analytic calculation provide rather good descriptions of the SDSS measurements. Thus, our results provide strong support for hierarchical models. They suggest that, unless care is taken to study galaxies at fixed mass, correlations between galaxy properties and the surrounding environment are almost entirely due to more fundamental correlations between galaxy properties and host halo mass, and between halo mass and environment.
description: 6 pages, 4 figures, paper replaced with accepted MNRAS version
title: Ιατρικός τουρισμός στην Ελλάδα, μελέτη περίπτωσης: ίδρυση μονάδας αιμοκάθαρσης σε δημόσιο κέντρο υγείας
title: Medical tourism in Greece, case study: establishment of a dialysis unit in a public health center
titleType: AlternativeTitle
Creators: name: Ζώτου, Φωτεινή
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2020
Subjects: subject: Ιατρικός τουρισμός
subject: Τεχνητό νεφρό
subject: Νομοθετικό πλαίσιο
subject: Δημόσιος τομέας
subject: Ιδιωτικός τομέας
subject: Τουρισμός

description: Η παρούσια εργασία με θέμα «Ιατρικός Τουρισμός στην Ελλάδα, Μελέτη Περίπτωσης: Ίδρυση μονάδας αιμοκάθαρσης σε δημόσιο κέντρο υγείας», εκπονείται στα πλαίσια των τελικών πτυχιακών εργασιών για την απόκτηση του Μεταπτυχιακού Διπλώματος του Τμήματος Οικονομικής Επιστήμης του Πανεπιστημίου Πειραιώς. Σκοπός: Κύριος σκοπός της εργασίας είναι η διερεύνηση της πιθανότητας ανάπτυξης του Ιατρικού Τουρισμού στην χώρα μας, μέσω δημιουργίας μονάδας αιμοκάθαρσης. Μεθοδολογία: Για την εκπλήρωση του σκοπού της εργασίας πραγματοποιήθηκε μελέτη περίπτωσης. Συγκεκριμένα, η συλλογή των βιβλιογραφικών στοιχείων πραγματοποιήθηκε από βιβλιογραφικές πηγές, καθώς και μέσω ξενόγλωσσων άρθρων, που σχετίζονται με την ανάπτυξη του Ιατρικού Τουρισμού. Για μελέτη περίπτωσης επιλέχθηκε μονάδα τεχνητού νεφρού, λόγω διαθεσιμότητας αρκετών στοιχείων και λόγω της ύψιστης σημασίας της πάθησης (αιμοκαθαρόμενοι). Αποτελέσματα: Σύμφωνα με τα κύρια αποτελέσματα, η ανάπτυξη του ιατρικού τουρισμού στην Ελλάδα αποτελεί μια νέα αγορά τόσο για τον ιατρικό όσο και για τον τουριστικό κλάδο. Η δυναμικότητα του ιατρικού τουρισμού αυξάνεται λόγω των κοινωνικών, πολιτικών, οικονομικών και δημογραφικών αλλαγών σε άλλες χώρες. Αναφορικά με την μελέτη περίπτωσης, το καθαρό αποτέλεσμα της μονάδας τεχνητού νεφρού δεν αναμένεται να αυξηθεί σημαντικά, γεγονός σχεδόν αναμενόμενο, δεδομένου ότι η πλειοψηφία των εσόδων είναι από κρατικούς πόρους και είναι υπολογισμένη για να καλύψει τα λειτουργικά έξοδα, παρόλα αυτά η Ελλάδα θα κατακτήσει μερίδιο αγοράς αργά και σταθερά, και επιπλέον είναι εφικτή η πρόσβαση στις υπηρεσίες υγείας, ειδικά σε ασθενείς που η αιμοκάθαρση δεν είναι επιλογή.
Evaluation of microsatellite instability in tumor and tumor marginal samples of sporadic colorectal cancer using mononucleotide markers
Creators: name: Nouri Nojadeh, Jafar
name: Hashemzadeh, Shahriar
name: Samadi Kafil, Hossein
name: Behrouz Sharif, Shahin
name: Eftekharsadat, Amirtaher
name: Ghasemnejad, Tohid
name: Ghojazadeh, Mortaza
name: Sakhinia, Ebrahim
Publisher: name: Technische Universität Dortmund
Year: 2018
Subjects: subject: CRC
subject: MSI
subject: DNA MMR system
subject: 610

description: Microsatellite instability (MSI) is a unique molecular alteration that is due to a defective DNA mismatch repair (MMR) system. Approximately, 15-20 % of sporadic colorectal cancers (CRC) display MSI. Determination of MSI status in CRC has prognostic and predictive implications. Additionally, detecting MSI is used diagnostically for tumor detection and classification. The present study analyzed a panel of five mononucleotide markers, BAT- 25, BAT-26, NR-21, NR-22 and NR-27, amplified in a single multiplex PCR reaction to evaluate MSI status in CRC patients. Genomic DNA from 50 CRC and paired adjacent normal tissues was used for PCR-based MSI analysis. Our finding showed microsatellite instability in 36 % of specimens. Instability with differences in allele lengths was observed in the tumoral DNA compared to the tumor-free margin DNA sample. The frequency of instability in NR-21, BAT-26 and BAT-25 markers were more than others; their frequency were 35.48 %, 29.03 %, and 22.58 %, respectively. In conclusion, the NR-21, BAT-26, and BAT-25 were the most useful markers for discriminating cancer tissue from normal, therefore these markers have demonstrated promising potential for determining MSI status in patients with sporadic colorectal cancer.
description: EXCLI Journal;Vol. 17 2018
Twisted Moduli Spaces and Duistermaat-Heckman Measures
Creators: name: Zerouali, Ahmed J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: Following Boalch-Yamakawa and Meinrenken, we consider a certain class of moduli spaces on bordered surfaces from a quasi-Hamiltonian perspective. For a given Lie group $G$, these character varieties parametrize flat $G$-connections on "twisted" local systems, in the sense that the transition functions take values in $G\rtimes\mathrm{Aut}(G)$. After reviewing the necessary tools to discuss twisted quasi-Hamiltonian manifolds, we construct a Duistermaat-Heckman (DH) measure on $G$ that is invariant under the twisted conjugation action $g\mapsto hgκ(h^{-1})$ for $κ\in\mathrm{Aut}(G)$, and characterize it by giving a localization formula for its Fourier coefficients. We then illustrate our results by determining the DH measures of our twisted moduli spaces.
description: 37 pages, 4 figures, 1 table
Η καινοτομία μέσω μάνατζμεντ και ηγεσίας στις επιχειρήσεις
Creators: name: Λάζαρη, Ελευθερία
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2020
Subjects: subject: Μάνατζμεντ
subject: Ηγεσία
subject: Καινοτομία

description: Η διπλωματική εργασία με τίτλο «Η καινοτομία μέσω μάνατζμεντ και ηγεσίας στις επιχειρήσεις» μελετά και ερευνά τον τρόπο που οι επιχειρήσεις διαχειρίζονται την καινοτομία μέσω του μάνατζμεντ και της ηγεσίας. Αρχικά πραγματοποιείται αποσαφήνιση και ανασκόπηση στις τρεις έννοιες που ασχολείται η εργασία, την ηγεσία, το μάνατζμεντ και την καινοτομία, στις μορφές τους και στα στάδια εξέλιξης τους. Στη συνέχεια εξετάζεται η σχέση που έχουν μεταξύ τους αλλά και πιο ειδικά στις επιχειρήσεις και τέλος μέσω των casy studies θα δούμε πώς κάποιες επιχειρήσεις έχουν καινοτομήσει. Επομένως θα ερευνηθεί κάθε είδους καινοτομία, ηγεσία και μάνατζμεντ που χρησιμοποιείται σε αυτόν τον κλάδο, τα οποία αποτελούν βασικά εργαλεία απόκτησης ανταγωνιστικού πλεονεκτήματος.
Dark galaxies or tidal debris? Kinematical clues to the origin of massive isolated HI clouds
Creators: name: Bekki, Kenji
name: Koribalski, Baerbel S.
name: Kilborn, Virginia A.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: An extended HI cloud (VIRGOHI 21) with an HI mass of $\sim10^8$ M$_{\odot}$ and no apparent optical counterpart was recently discovered in the Virgo cluster. In order to understand the origin of physical properties of apparently isolated HI clouds like the VIRGOHI21, we numerically investigate physical properties of tidal HI debris that were formed by galaxy-galaxy interaction in clusters of galaxies. Our hydrodynamical simulations demonstrate that tidal debris with total HI masses of $10^8-10^9$ M$_{\odot}$ can have (1) wide HI velocity widths ($>200$ km s$^{-1}$), (2) a small mass fraction of stars ($\sim$10%), and (3) a mean $B$-band surface brightness of the stellar components fainter than 30 mag arcsec$^{-2}$. These results suggest that the VIRGOHI21, which lies at a projected distance of $\sim$ 150 kpc from the one-armed, HI-rich spiral galaxy M99 (NGC 4254), is tidal debris. We propose that the comparison between the simulated and the observed velocity fields of HI clouds allows us to better understand their nature and origin (e.g., whether they are just tidal debris or ``dark galaxies'' that have HI gas only and are embedded by dark matter halos). We also discuss the timescales for isolated HI gas to be evaporated by thermal conduction of the hot intracluster gas.
description: 5 pages, 5 figures (three color figures), submitted to MNRAS
An automated method for the evaluation of breast cancer using infrared thermography
Creators: name: Morales-Cervantes, Antony
name: Kolosovas-Machuca, Eleazar Samuel
name: Guevara, Edgar
name: Maruris Reducindo, Mireya
name: Bello Hernández, Alix Berenice
name: Ramos García, Manuel
name: González, Francisco Javier
Publisher: name: Technische Universität Dortmund
Year: 2018
Subjects: subject: Breast cancer
subject: Infrared thermography
subject: Automated screening
subject: 610

description: Breast cancer is one of the major causes of death for women. Temperature measurement is advantageous because it is non-invasive, non-destructive, and cost-effective. Temperature measurement through infrared thermography is useful to detect changes in blood perfusion that can occur due to inflammation, angiogenesis, or other pathological causes. In this work, we analyzed 206 thermograms of patients with suspected breast cancer, using a classification method, in which thermal asymmetries were computed, the most vascularized areas of each breast were extracted and compared; then these two metrics were added to yield a thermal score, indicative of thermal anomalies. The classification method based on this thermal score allowed us to obtain the test sensitivity of 100 %, specificity of 68.68 %; a positive predictive value of 11.42 % and negative predictive value of 100 %. These results highlight the potential of thermography imaging as adjunctive tool to mammography in breast cancer screening.
description: EXCLI Journal;Vol. 17 2018
Subjective and Objective Probabilities in Quantum Mechanics
Creators: name: Srednicki, Mark
Publisher: name: arXiv
Year: 2005
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We discuss how the apparently objective probabilities predicted by quantum mechanics can be treated in the framework of Bayesian probability theory, in which all probabilities are subjective. Our results are in accord with earlier work by Caves, Fuchs, and Schack, but our approach and emphasis are different. We also discuss the problem of choosing a noninformative prior for a density matrix.
description: 6 pages, RevTeX; references added in version 2
Investigating Heavy-flavor vs Light-flavor Puzzle with Event Topology and Multiplicity in Proton+Proton Collisions at $\sqrt{s}$ = 13 TeV using PYTHIA8
Creators: name: Deb, Suman
name: Sahoo, Raghunath
name: Thakur, Dhananjaya
name: Tripathy, Sushanta
name: Khuntia, Arvind
Publisher: name: arXiv
Year: 2020
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Heavy-flavored hadrons are unique probes to study the properties of hot and dense QCD medium produced in ultra-relativistic heavy-ion collisions at RHIC and the LHC. Transverse spherocity is one of the event-topology variables used to separate jetty and isotropic events from the pool of event samples. This study aims to understand the production dynamics of heavy-flavors through the transverse momentum spectra, double differential yield and mean transverse momentum of J/$ψ$, $\rm D^{0}$ and $Λ_{c}^{+}$ as a function of charged-particle multiplicity and transverse spherocity. Further to investigate the possibility of hardonization of the charm quarks, transverse spherocity dependence ratios like $Λ_{c}^{+}$/$\rm D^{0}$ and $Λ^{0}$/$K^{-}$ are studied. For the current analysis, the events are generated by using 4C tuned PYTHIA8 for pp at $\sqrt{s}$ = 13 TeV, which is quite successful in explaining the heavy-flavor particle production at the LHC energies.
description: Same as the published version
A market assessment of wood use in Japanese residential flooring of windows
Creators: name: Wahl, Antje
Publisher: name: University of British Columbia
Year: 2009

description: In the past, building products for residential construction in Japan were produced almost exclusively domestically. However, imports of building products such as wood flooring and wood windows have been increasing for economic reasons and because many imported western-style products are not available on the domestic market. The purpose of this study is to find out more about Japanese products, markets and industry in wood flooring and windows, since little information exists for potential suppliers outside of Japan. The study collected exploratory information through personal interviews with house builders in Japan and a fax survey among manufacturers of wood flooring and windows in Canada. The Japanese wood flooring market is very large and is supplied primarily by domestic production. The most common type is composite flooring made of plywood or fibreboard overlaid with veneer. Based on information gathered in this study, respondents preferred ready-to-install, light, colour-matched floors with polyurethane finish. The best opportunities for Canadian manufacturers exist for moderately priced solid softwood and hardwood flooring and for ready-to-install veneered softwood flooring. Japan's window market is dominated by aluminium, but the demand for wood windows is growing and most of this demand is covered by imports. Northern Japan and residential areas where fire regulations do not apply present the best potential markets for wood windows. Aluminium-clad wood windows have the best prospects. While the Japanese housing market is shrinking in the long-term, opportunities are identified in the growing markets for wood flooring and windows.
Graph-based calibration transfer
Creators: name: Nikzad-Langerodi, Ramin
name: Sobieczky, Florian
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: Methodology (stat.ME)
subject: FOS: Computer and information sciences

description: The problem of transferring calibrations from a primary to a secondary instrument, i.e. calibration transfer (CT), has been a matter of considerable research in chemometrics over the past decades. Current state-of-the-art (SoA) methods like (piecewise) direct standardization perform well when suitable transfer standards are available. However, stable calibration standards that share similar (spectral) features with the calibration samples are not always available. Towards enabling CT with arbitrary calibration standards, we propose a novel CT technique that employs manifold regularization of the partial least squares (PLS) objective. In particular, our method enforces that calibration standards, measured on primary and secondary instruments, have (nearly) invariant projections in the latent variable space of the primary calibration model. Thereby, our approach implicitly removes inter-device variation in the predictive directions of X which is in contrast to most state-of-the-art techniques that employ explicit pre-processing of the input data. We test our approach on the well-known corn benchmark data set employing the NBS glass standard spectra for instrument standardization and compare the results with current SoA methods.
description: Preprint submitted to Journal of Chemometrics
Relative entropy of coherent states on general CCR algebras
Creators: name: Bostelmann, Henning
name: Cadamuro, Daniela
name: Del Vecchio, Simone
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 81T05 (Primary) 46N50, 94A17 (Secondary)

description: For a subalgebra of a generic CCR algebra, we consider the relative entropy between a general (not necessarily pure) quasifree state and a coherent excitation thereof. We give a unified formula for this entropy in terms of single-particle modular data. Further, we investigate changes of the relative entropy along subalgebras arising from an increasing family of symplectic subspaces; here convexity of the entropy (as usually considered for the Quantum Null Energy Condition) is replaced with lower estimates for the second derivative, composed of "bulk terms" and "boundary terms". Our main assumption is that the subspaces are in differential modular position, a regularity condition that generalizes the usual notion of half-sided modular inclusions. We illustrate our results in relevant examples, including thermal states for the conformal $U(1)$-current.
description: slight shortening in Sec. 3; as to appear in Commun. Math. Phys.; 24 pages
Enhanced Quantum Reflection of Matter-Wave Solitons
Creators: name: Lee, Chaohong
name: Brand, Joachim
Publisher: name: arXiv
Year: 2005
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: Matter-wave bright solitons are predicted to reflect from a purely attractive potential well although they are macroscopic objects with classical particle-like properties. The non-classical reflection occurs at small velocities and a pronounced switching to almost perfect transmission above a critical velocity is found, caused by nonlinear mean-field interactions. Full numerical results from the nonlinear Schrödinger equation are complimented by a two-mode variational calculation to explain the predicted effect, which can be used for velocity filtering of solitons. The experimental realization with laser-induced potentials or two-component Bose-Einstein condensates is suggested.
description: 7 pages, 3 figures, to be published in Europhys. Lett
title: Digital transformation στον τουρισμό
title: Digital transformation in tourism
titleType: AlternativeTitle
Creators: name: Βασίλαρου, Ελένη
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2020
Subjects: subject: Τουρισμός
subject: Ψηφιακός μετασχηματισμός
subject: Διαδικτυακά συστήματα κρατήσεων
subject: Διαδικτυακές αξιολογήσεις

description: Στόχος αυτής της έρευνας είναι να εξετάσει τις επιπτώσεις της τεχνολογίας στον τουριστικό τομέα. Πιο συγκεκριμένα, οι τεχνολογίες που εξετάζονται είναι τα ηλεκτρονικά συστήματα κρατήσεων μαζί με τα παγκόσμια συστήματα διανομής, η χρήση των κοινωνικών μέσων και οι διαδικτυακές αναθεωρήσεις. Για τους σκοπούς αυτής της έρευνας χρησιμοποιήθηκε μια ποσοτική μέθοδος, με ερωτηματολόγια σε πολίτες της χώρας. Τα αποτελέσματα της μελέτης έδειξαν ότι πράγματι η τεχνολογία έχει αλλάξει τον τουριστικό τομέα, και ιδιαίτερα τη βιομηχανία φιλοξενίας, καθώς η έρευνα διεξήχθη σε διευθυντές και επισκέπτες του ξενοδοχείου. Συγκεκριμένα, τα ευρήματα αυτής της έρευνας αποκάλυψαν ότι τα συστήματα κρατήσεων, τα μέσα κοινωνικής δικτύωσης και οι διαδικτυακές κριτικές επιτρέπουν την καλύτερη αλληλεπίδραση μεταξύ των τουριστικών επιχειρήσεων και των καταναλωτών, διευκολύνουν το μάρκετινγκ και τη μεγαλύτερη έκθεση για λογαριασμό της επιχείρησης, βελτιώνουν την ποιότητα των υπηρεσιών και παρέχουν προσαρμοσμένες υπηρεσίες στους πελάτες μέσω της γνώσης πελατών που προσφέρει η ανατροφοδότηση, αυξάνει τη διαπραγματευτική δύναμη των ξενοδοχείων λόγω των διαδικτυακών αναθεωρήσεων και γενικά οδηγεί σε αυξημένη εμπιστοσύνη των πελατών, αναγνώριση του εμπορικού σήματος, ικανοποίηση πελατών και πίστη και κερδοφορία του ξενοδοχείου. Έτσι, αναμένεται ότι ο τουριστικός τομέας, και ιδιαίτερα ο κλάδος της φιλοξενίας, θα στηριχθεί σε μεγάλο βαθμό στην τεχνολογία τα επόμενα χρόνια. Ωστόσο, απαιτείται περαιτέρω έρευνα σε άλλες τουριστικές επιχειρήσεις και τους επισκέπτες τους, προκειμένου να αξιολογηθεί ο αντίκτυπος της τεχνολογίας και της ψηφιοποίησης σε ολόκληρο τον τομέα του τουρισμού.
Everolimus, a mammalian target of rapamycin inhibitor, ameliorated streptozotocin-induced learning and memory deficits via neurochemical alterations in male rats
Creators: name: Fanoudi, Sahar
name: Hosseini, Mahmoud
name: Alavi, Mohaddeseh Sadat
name: Boroushaki, Mohammad Taher
name: Hosseini, Azar
name: Sadeghnia, Hamid R.
Publisher: name: Technische Universität Dortmund
Year: 2018
Subjects: subject: Everolimus
subject: mTOR
subject: Alzheimer’s disease (AD)
subject: Oxidative stress
subject: Acetylcholinesterase
subject: Streptozotocin
subject: 610

description: Everolimus (EVR), as a rapamycin analog, is a selective inhibitor of the mammalian target of rapamycin (mTOR) kinase and its associated signaling pathway. mTOR is a serine/threonine protein kinase and its hyperactivity is involved in the pathophysiology of Alzheimer’s disease (AD) and associated cognitive deficits. The present study evaluated the impact of EVR, on cognitive functions, hippocampal cell loss, and neurochemical parameters in the intracerebroventricular streptozotocin (icv-STZ) model of AD rats. EVR (1 and 5 mg/kg) was administered for 21 days following the single administration of STZ (3 mg/kg, icv) or for 7 days on days 21-28 post-STZ injection after establishment of cognitive dysfunction. Cognitive deficits (passive avoidance and spatial memory), oxidative stress parameters, acetylcholinesterase (AChE) activity, and percentage of cell loss were evaluated in the hippocampus. Chronic administration (1 and 5 mg/kg for 21 days from the day of surgery and icv-STZ infusion) or acute injection (5 mg/kg for 7 days after establishment of cognitive impairment) of EVR significantly attenuated cognitive dysfunction, neuronal loss, oxidative stress and AChE activity in the hippocampus of STZ-AD rats. In conclusion, our study showed that EVR could prevent or improve deteriorations in behavioral, biochemical and histopathological features of the icv-STZ rat model of AD. Therefore, inhibition of the hyperactivated mTOR may be an important therapeutic target for AD.
description: EXCLI Journal;Vol. 17 2018
The Reduced Phase Space of An Open String in The Background B-Field
Creators: name: Dehghani, M.
name: Shirzad, A.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The problem of an open string in background $B$-field is discussed. Using the discretized model in details we show that the system is influenced by infinite number of second class constraints. We interpret the allowed Fourier modes as the coordinates of the reduced phase space. This enables us to compute the Dirac brackets more easily. We prove that the coordinates of the string are non-commutative at the boundaries. We argue that in order to find the Dirac bracket or commutator algebra of the physical variables, one should not expand the fields in terms of the solutions of the equations of motion. Instead, one should impose the set of constraints in suitable coordinates.
description: 21 pages, no figures
Consistent second-order discrete kernel smoothing using dispersed Conway-Maxwell-Poisson kernels
Creators: name: Huang, Alan
name: Sippel, Lucas
name: Fung, Thomas
Publisher: name: arXiv
Year: 2020
Subjects: subject: Methodology (stat.ME)
subject: FOS: Computer and information sciences
subject: 62G07

description: The histogram estimator of a discrete probability mass function often exhibits undesirable properties related to zero probability estimation both within the observed range of counts and outside into the tails of the distribution. To circumvent this, we formulate a novel second-order discrete kernel smoother based on the recently developed mean-parametrized Conway--Maxwell--Poisson distribution which allows for both over- and under-dispersion. Two automated bandwidth selection approaches, one based on a simple minimization of the Kullback--Leibler divergence and another based on a more computationally demanding cross-validation criterion, are introduced. Both methods exhibit excellent small- and large-sample performance. Computational results on simulated datasets from a range of target distributions illustrate the flexibility and accuracy of the proposed method compared to existing smoothed and unsmoothed estimators. The method is applied to the modelling of somite counts in earthworms, and the number of development days of insect pests on the Hura tree.
description: 12 pages, 3 figures, 2 tables. (to appear in Computational Statistics)
title: Comparing task performance, visual comfort and alertness under different lighting sources
title: an experimental study
titleType: AlternativeTitle
Creators: name: Kazemi, Reza
name: Choobineh, Alireza
name: Taheri, Shirin
name: Rastipishe, Pegah
Publisher: name: Technische Universität Dortmund
Year: 2018
Subjects: subject: Lighting
subject: Performance
subject: Alertness
subject: Comfort
subject: 610

description: The aim of this study is to compare the effects of different light sources – namely light-emitting diode (LED), compact fluorescent (FLcomp) and fluorescent with warm color temperature (FLwarm) and cool color temperature (FLcool) – on the performances, alertness, visual comfort level and preferences in a pilot study. A laboratory controlled experiment was conducted by focusing on 20 postgraduate students who volunteered to participate in a series of tests under four different light sources. “GO NO GO” task and Karolinska Sleepiness Scale (KSS) were employed to assess objective and subjective alertness, while modified OLS questionnaire was used to gauge comfort level and preferences. In addition, editing and typing tasks were carried out as a performance evaluation. Significant increase was observed in subjective and objective alertness level under FLcool condition and LED in comparison to FLwarm and FLcomp (p < 0.05). In terms of typing performances, respondents performed significantly better with regard to typing speed under FLcool than FLwarm and FLcomp. The lowest number of typing errors was made under FLcool, followed by LED, FLcomp and FLwarm. LED was the most preferred (p=0.001) and most comfortable (p=0.011) lighting condition. The study concludes that the FLcool and LED were more beneficial for alertness level and performance for both computer-based and paper-based activities.
description: EXCLI Journal;Vol. 17 2018
Παράγοντες πιστότητας πελατών και μεριδίου πορτοφολιού στην λιανική τραπεζική
Creators: name: Κούστας, Σπυρίδων
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2020
Subjects: subject: Πιστότητα πελατών
subject: Μερίδιο πορτοφολιού
subject: Λιανική τραπεζική

description: Ο βασικός σκοπός της παρούσας διπλωματικής εργασίας ήταν να διερευνηθούν οι παράγοντες πελατειακής πιστότητας αλλά και οι παράγοντες που επηρεάζουν το μερίδιο του πορτοφολιού των πελατών στον κλάδο της λιανικής τραπεζικής, στην Ελληνική αγορά. Η ερευνά βασίστηκε σε πρωτογενή δεδομένα και συγκεκριμένα στη χρήση ερωτηματολογίων. Έτσι τα δεδομένα που συλλέχθηκαν από 260 πελάτες λιανικής τραπεζικής υποδηλώνουν ότι μεγάλο ποσοστό της διακύμανσης στις εξαρτημένες μεταβλητές της έρευνας, μπορεί να προβλεφθεί από 6 κύριους παράγοντες. Όσον αφορά τους ερευνητικούς στόχους συμπεράναμε πως τόσο η πιστότητα των πελατών όσο και το μερίδιο πορτοφολιού τους, επηρεάζονται κατά κύριο λόγο από την ευκολία στη χρήση και την ασφάλεια της πλατφόρμας ηλεκτρονικής τραπεζικής της κάθε τράπεζας. Ωστόσο κάποιες εξίσου σημαντικές επιρροές στη πιστότητα και στο μερίδιο πορτοφολιού ασκούν τα επιτόκια των καταθέσεων, των δανείων αλλά και οι προμήθειες που χρεώνουν οι τράπεζες για την εκτέλεση των καθημερινών τραπεζικών συναλλαγών. Τέλος, τα προγράμματα πιστότητας-επιβράβευσης που προσφέρουν οι τράπεζες, βρέθηκε ότι αποτελούν σημαντικό παράγοντα μακροχρόνιας πρόθεσης παραμονής στην κύρια τράπεζα.
title: Social innovation as a driver for new educational practices
title: modernising, repairing and transforming the education system
titleType: AlternativeTitle
Creators: name: Schröder, Antonius
name: Krüger, Daniel
Publisher: name: Technische Universität Dortmund
Year: 2019
Subjects: subject: Social innovation
subject: Education
subject: Sustainable transformation
subject: Lifelong learning
subject: Innovation ecosystem
subject: 300
subject: Sozialinnovation
subject: Erziehung
subject: Lebenslanges Lernen
subject: Bildungssystem

description: Based on the results of the EU funded Social Innovation – Driving Force of Social Change (SI-DRIVE) project the major challenges and needs of education and lifelong learning worldwide are revealed, focusing on solutions via new educational practices delivered by social innovations and embedding civil society. Against this background, a more learner-oriented approach instead of institutional improvements is presented. Based on the results of SI-DRIVE’s global mapping of more than 200 innovative education initiatives and 18 in-depth case studies, the article spotlights the relevant settings and success factors of social innovations in education, leading to a system related typology of social innovation. New ways of repairing, modernising and transforming education as well as separated approaches are illustrated showing the underdeveloped, unexploited and unrecognised potential of this kind of innovation. For setting up a more innovation friendly environment, it is particularly important to realise a paradigm shift towards a learner perspective and rationality. More leeway and new governance structures for integrating and fostering social innovations and unfolding the potential of all societal sectors for enhancing education are necessary. This especially includes a more active and new role of universities in enabling, exchanging, moderating and researching social innovation.
Blood-based epigenome-wide analyses of cognitive abilities - Analysis code
Creators: name: McCartney, Daniel L
name: Hillary, Robert F
name: Conole, Eleanor LS
name: Trejo Banos, Daniel
name: Gadd, Danni A
name: Walker, Rosie M
name: Nangle, Cliff
name: Flaig, Robin
name: Campbell, Archie
name: Murray, Alison D
name: Munoz Maniega, Susana
name: del C Valdes-Hernandez, Maria
name: Harris, Mathew A
name: Bastin, Mark E
name: Wardlaw, Joanna M
name: Harris, Sarah E
name: Porteous, David J
name: Tucker-Drob, Elliot M
name: McIntosh, Andrew M
name: Evans, Kathryn L
name: Deary, Ian J
name: Cox, Simon R
name: Robinson, Matthew R
name: Marioni, Riccardo E
Publisher: name: Zenodo
Year: 2021

description: Analysis code for Blood-based epigenome-wide analyses of cognitive abilities. For CpG weights see https://doi.org/10.5281/zenodo.5794029
Minimal archi-texture for neutrino mass matrices
Creators: name: Watanabe, Atsushi
name: Yoshioka, Koichi
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The origin of the observed masses and mixing angles of quarks and leptons is one of imperative subjects in and beyond the standard model. Toward a deeper understanding of flavor structure, we investigate in this paper the minimality of fermion mass (Yukawa) matrices in unified theory. That is, the simplest matrix form is explored in light of the current experimental data for quarks and leptons, including the recent measurements of quark CP violation and neutrino oscillations. Two types of neutrino mass schemes are particularly analyzed; (i) Majorana masses of left-handed neutrinos with unspecified mechanism and (ii) Dirac and Majorana masses introducing three right-handed neutrinos. As a result, new classes of neutrino mass matrices are found to be consistent to the low-energy experimental data and high-energy unification hypothesis. For distinctive phenomenological implications of the minimal fermion mass textures, we discuss flavor-violating decay of charged leptons, the baryon asymmetry of the universe via thermal leptogenesis, neutrino-less double beta decay, and low-energy leptonic CP violation.
description: 37 pages, 6 figures
Edge states of the long-range Kitaev chain: an analytical study
Creators: name: Jäger, Simon B.
name: Dell'Anna, Luca
name: Morigi, Giovanna
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We analyze the properties of the edge states of the one-dimensional Kitaev model with long-range anisotropic pairing and tunneling. Tunneling and pairing are assumed to decay algebraically with exponents $α$ and $β$, respectively, and $α,β>1$. We determine analytically the decay of the edges modes. We show that the decay is exponential for $α=β$ and when the coefficients scaling tunneling and pairing terms are equal. Otherwise, the decay is exponential at sufficiently short distances and then algebraic at the asymptotics. We show that the exponent of the algebraic tail is determined by the smallest exponent between $α$ and $β$. Our predictions are in agreement with numerical results found by exact diagonalization and in the literature.
description: 8 pages, 3 figures
Portfolio selection using neural networks
Creators: name: Fernandez, Alberto
name: Gomez, Sergio
Publisher: name: arXiv
Year: 2005
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Computer and information sciences

description: In this paper we apply a heuristic method based on artificial neural networks in order to trace out the efficient frontier associated to the portfolio selection problem. We consider a generalization of the standard Markowitz mean-variance model which includes cardinality and bounding constraints. These constraints ensure the investment in a given number of different assets and limit the amount of capital to be invested in each asset. We present some experimental results obtained with the neural network heuristic and we compare them to those obtained with three previous heuristic methods.
description: 12 pages; submitted to "Computers & Operations Research"
Charge Conjugation Invariance of the Vacuum and the Cosmological Constant Problem
Creators: name: Moffat, J. W.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We propose a method of field quantization which uses an indefinite metric in a Hilbert space of state vectors. The action for gravity and the standard model includes, as well as the positive energy fermion and boson fields, negative energy fields. The Hamiltonian for the action leads through charge conjugation invariance symmetry of the vacuum to a cancellation of the zero-point vacuum energy and a vanishing cosmological constant in the presence of a gravitational field. To guarantee the stability of the vacuum, we introduce a Dirac sea `hole' theory of quantization for gravity as well as the standard model. The vacuum is defined to be fully occupied by negative energy particles with a hole in the Dirac sea, corresponding to an anti-particle. We postulate that the negative energy bosons in the vacuum satisfy a para-statistics that leads to a para-Pauli exclusion principle for the negative energy bosons in the vacuum, while the positive energy bosons in the Hilbert space obey the usual Bose-Einstein statistics. This assures that the vacuum is stable for both fermions and bosons. Restrictions on the para-operator Hamiltonian density lead to selection rules that prohibit positive energy para-bosons from being observable. The problem of deriving a positive energy spectrum and a consistent unitary field theory from a pseudo-Hermitian Hamiltonian is investigated.
description: 15 pages, Latex file, no figures. Typos corrected. To be published in Physics Letters B
Topological and geometric patterns in optimal bang-bang protocols for variational quantum algorithms: application to the $XXZ$ model on the square lattice
Creators: name: Scoggins, Matthew T.
name: Rahmani, Armin
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: In this work, we address the challenge of uncovering patterns in variational optimal protocols for taking the system to ground states of many-body Hamiltonians, using variational quantum algorithms. We develop highly optimized classical Monte Carlo (MC) algorithms to find the optimal protocols for transformations between the ground states of the square-lattice XXZ model for finite systems sizes. The MC method obtains optimal bang-bang protocols, as predicted by Pontryagin's minimum principle. We identify the minimum time needed for reaching an acceptable error for different system sizes as a function of the initial and target states and uncover correlations between the total time and the wave-function overlap. We determine a dynamical phase diagram for the optimal protocols, with different phases characterized by a topological number, namely the number of on-pulses. Bifurcation transitions as a function of initial and final states, associated with new jumps in the optimal protocols, demarcate these different phases. The number of pulses correlates with the total evolution time. In addition to identifying the topological characteristic above, i.e., the number of pulses, we introduce a correlation function to characterize bang-bang protocols' quantitative geometric similarities. We find that protocols within one phase are indeed geometrically correlated. Identifying and extrapolating patterns in these protocols may inform efficient large-scale simulations on quantum devices.
description: 14 pages, 13 figures
Η αγορά του καφέ στην περίπτωση της Ελλάδας
Creators: name: Ευαγγελίου, Νικόλαος
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2020
Subjects: subject: Καφές
subject: Διεθνής αγορά καφέ
subject: Ελληνική αγορά καφέ
subject: Εισαγωγές και εξαγωγές καφέ

description: Η παρούσα μελέτη αποτελεί μεταπτυχιακή διατριβή κατά την οποία διερευνάται ο κλάδος του καφέ στην ελληνική αγορά. Θα επιχειρηθεί μια ανάλυση της ελληνικής κουλτούρας σε σχέση με τον καφέ και πως αυτή γίνεται αισθητή μέσα από διάφορες καταναλωτικές συνήθειες. Παράλληλα γίνεται αναφορά στην ανάλυση της ζήτησης και της προσφοράς καθώς και των επιμέρους παραγόντων που διαμορφώνουν τις δυνάμεις αυτές της ελληνικής αγοράς. Ερευνά τη Διεθνή αγορά καφέ και ποιες χώρες είναι κυρίαρχες στο συγκεκριμένο προϊόν μέσα από τις εισαγωγές/εξαγωγές αλλά και τις πωλήσεις που πραγματοποιούν τόσο τα τελευταία χρόνια όσο και τα παλαιότερα ώστε να αντιληφθούμε καλύτερα το πόσο ισχυρό προϊόν είναι ο καφές. Μελετά την πορεία των ελληνικών εισαγωγών και εξαγωγών καφέ και προσπαθεί να εξάγει συμπεράσματα για τις προοπτικές εξέλιξης τους. Ειδικότερα, εξετάζονται οι εξής κατηγορίες προϊόντων: ελληνικός καφές, στιγμιαίος, φίλτρου και καφές espresso.
Στρατηγική επιχειρήσεων ενεργειακών μελετών: μελέτη περίπτωσης αξιολόγησης ενεργειακής αναβάθμισης δημοσίου κτιρίου
Creators: name: Mανώλη, Ερασμία
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2020
Subjects: subject: Ενεργειακή αναβάθμιση
subject: Εταιρείες ενεργειακών υπηρεσιών

description: Η παρούσα διπλωματική εργασία εξετάζει την Στρατηγική Ενεργειακών Μελετών, δίνοντας έμφαση στην μελέτη περίπτωσης που αφορά την ενεργειακή αναβάθμιση του Νοσοκομείου Καστοριάς. Αρχικά, μελετάται η ενεργειακή αποδοτικότητα των κτιρίων, εξετάζοντας τόσο την επικρατούσα κατάσταση στην Ελλάδα, όσο και στο διεθνές στερέωμα. Ακολούθως, στο δεύτερο κεφάλαιο γίνεται λόγος για τις εταιρείες ενεργειακών υπηρεσιών στην Ελλάδα, δίνοντας έμφαση στην εφαρμογή ESCOs σε κτίρια του δημοσίου τομέα. Περαιτέρω, γίνεται οικονομοτεχνική μελέτη ενεργειακής αναβάθμισης του Νοσοκομείου Καστοριάς και διαμορφώνονται ορισμένα σενάρια χρηματοδότησης και αποπληρωμής των αναγκαίων δαπανών. Προκειμένου να αναπτυχθεί το υπό εξέταση ζήτημα γίνεται βιβλιογραφική αναζήτηση σε διεθνείς βάσεις επιστημονικών δεδομένων, δίνοντας έμφαση σε επιστημονικά περιοδικά που πραγματεύονται ζητήματα εξοικονόμησης ενέργειας, καθώς επίσης και σε μελέτες που αφορούν παρεμβάσεις εξοικονόμησης ενέργειας σε δημόσια κτίρια. Στο δεύτερο σκέλος της εργασίας, για την πραγματοποίηση της οικονομοτεχνικής μελέτης χρησιμοποιείται το πρόγραμμα excel, ενώ ο υπολογισμός της εξοικονόμησης έγινε με το λογισμικό ΤΕΕ ΚΕΝΑΚ, με βάση τα στοιχεία που αναφέρονται στη μελέτη.
"Root" Action for N=4 Supersymmetric Mechanics Theories
Creators: name: Bellucci, S.
name: Krivonos, S.
name: Marrani, A.
name: Orazi, E.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We propose to consider the N=4,d=1 supermultiplet with $% (4,4,0) component content as a ``root'' one. We elaborate a new reduction scheme from the ``root'' multiplet to supermultiplets with a smaller number of physical bosons. Starting from the most general sigma-model type action for the ``root'' multiplet, we explicitly demonstrate that the actions for the rest of linear and nonlinear N=4 supermultiplets can be easily obtained by reduction. Within the proposed reduction scheme there is a natural possibility to introduce Fayet-Iliopoulos terms. In the reduced systems, such terms give rise to potential terms, and in some cases also to terms describing the interaction with a magnetic field. We demonstrate that known N=4 superconformal actions, together with their possible interactions, appear as results of the reduction from a free action for the ``root'' supermultiplet. As a byproduct, we also construct an N=4 supersymmetric action for the linear (3,4,1) supermultiplet, containing both an interaction with a Dirac monopole and a harmonic oscillator-type potential, generalized for arbitrary conformally flat metrics.
description: 12 pages