Myths and cults of ancient Tenea

Since 2013, an excavation is being carried out in Chiliomodi, Corinthia, where ancient Tenea was located. Ancient sources give us very useful information about its topographic location and associate to with extremely important myths, such as the mythical cycle of the Trojan War and the myth of Oedipus. According to ancient literature, the main deity worshiped in Tenea was Apollo. Archaeological excavations have revealed a wealth of data that indirectly illuminates aspects of the cults of this city

Hyperledger Fabric: A Distributed Operating System for Permissioned Blockchains

Fabric is a modular and extensible open-source system for deploying and operating permissioned blockchains and one of the Hyperledger projects hosted by the Linux Foundation (www.hyperledger.org). Fabric is the first truly extensible blockchain system for running distributed applications. It supports modular consensus protocols, which allows the system to be tailored to particular use cases and trust models. Fabric is also the first blockchain system that runs distributed applications written in standard, general-purpose programming languages, without systemic dependency on a native cryptocurrency. This stands in sharp contrast to existing blockchain platforms that require "smart-contracts" to be written in domain-specific languages or rely on a cryptocurrency. Fabric realizes the permissioned model using a portable notion of membership, which may be integrated with industry-standard identity management. To support such flexibility, Fabric introduces an entirely novel blockchain design and revamps the way blockchains cope with non-determinism, resource exhaustion, and performance attacks. This paper describes Fabric, its architecture, the rationale behind various design decisions, its most prominent implementation aspects, as well as its distributed application programming model. We further evaluate Fabric by implementing and benchmarking a Bitcoin-inspired digital currency. We show that Fabric achieves end-to-end throughput of more than 3500 transactions per second in certain popular deployment configurations, with sub-second latency, scaling well to over 100 peers.Comment: Appears in proceedings of EuroSys 2018 conferenc

New Mediterranean Biodiversity Records (November 2018)

In the present article, new records are given for 18 species (6 native, 9 alien and 3 cryptogenic), belonging to 5 Phyla (i.e. Chlorophyta, Cnidaria, Annelida, Mollusca and Chordata), from 8 Mediterranean countries: Spain: A large population of Polycerella emertoni reported from the Ebro Delta, the presence of pinimuricea klavereni is confirmed for the first time in the Catalan coast; Italy: the new record of Cryptonome turcica extends its distribution to the western Mediterranean Sea, the findings of Mawia benovici constitute the southernmost record of this species in the Adriatic Sea; Slovenia: second record of the alien seaslug Cuthona perca in the Mediterranean Sea; Montenegro: Styela plicata communities were recorded in Boka Kotorska Bay; Albania: the native great torpedo ray Tetronarce nobiliana recorded for the first time in Albanian waters; Greece: first record of Lagocephalus sceleratus in the Greek side of the Adriatic, the records of Cassiopea andromeda and Pterois miles are first records of these species from the Ionian Sea, the colonial ascidians Aplidium coeruleum and Didemnum protectum are recorded for the first time in the Eastern Mediterranean, an extremely abundant population of Melibe viridis is found in Messolonghi lagoon, the record of Synchiropus sechellensis is the range expansion of this species in Greek Seas, Acetabularia caliculus is recorded for the first time from Greece; Cyprus: first records of Callionymus filamentosus and Haminoea cyanomarginata from the island; Turkey: the presence of Berthellina citrina in the Mediterranean is confirmed.info:eu-repo/semantics/publishedVersio

A MSFD complementary approach for the assessment of pressures, knowledge and data gaps in Southern European Seas : the PERSEUS experience

PERSEUS project aims to identify the most relevant pressures exerted on the ecosystems of the Southern European Seas (SES), highlighting knowledge and data gaps that endanger the achievement of SES Good Environmental Status (GES) as mandated by the Marine Strategy Framework Directive (MSFD). A complementary approach has been adopted, by a meta-analysis of existing literature on pressure/impact/knowledge gaps summarized in tables related to the MSFD descriptors, discriminating open waters from coastal areas. A comparative assessment of the Initial Assessments (IAs) for five SES countries has been also independently performed. The comparison between meta-analysis results and IAs shows similarities for coastal areas only. Major knowledge gaps have been detected for the biodiversity, marine food web, marine litter and underwater noise descriptors. The meta-analysis also allowed the identification of additional research themes targeting research topics that are requested to the achievement of GES. 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license.peer-reviewe

The future of road transport

A perfect storm of new technologies and new business models is transforming not only our vehicles, but everything about how we get around, and how we live our lives. The JRC report “The future of road transport - Implications of automated, connected, low-carbon and shared mobility” looks at some main enablers of the transformation of road transport, such as data governance, infrastructures, communication technologies and cybersecurity, and legislation. It discusses the potential impacts on the economy, employment and skills, energy use and emissions, the sustainability of raw materials, democracy, privacy and social fairness, as well as on the urban context. It shows how the massive changes on the horizon represent an opportunity to move towards a transport system that is more efficient, safer, less polluting and more accessible to larger parts of society than the current one centred on car ownership. However, new transport technologies, on their own, won't spontaneously make our lives better without upgrading our transport systems and policies to the 21st century. The improvement of governance and the development of innovative mobility solutions will be crucial to ensure that the future of transport is cleaner and more equitable than its car-centred present.JRC.C.4-Sustainable Transpor

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Behavior and strengthening of nonconforming reinforced concrete shear walls

The present doctoral thesis refers to the experimental and numerical/analytical study of the behavior of reinforced concrete walls, characterized by the absence of the configuration of confined boundary elements and small shear reinforcement ratios, as well as to the evaluation of different strengthening methods. The experimental procedure consisted of the experimental test of a total of 16 medium rise shear walls (eight non-strengthened, seven strengthened and one repaired/ strengthened), which were studied as cantilevers under static cyclic loading. As regards the strengthening methods, the application of Fibers Reinforced Polymers (FRP) sheets and the application of steel elements (strips and angles) were examined. As shown from the experimental results the failure of the non-strengthened walls is associated in all cases with the failure of the compressive zone which is accelerated by the buckling of the longitudinal compressive reinforcement bars. As far as the shear reinforcement is concerned, it appeared to have a greater impact on the extent of the web cracking, and thus on the energy dissipation values and the shear deformation values, and less on the bearing capacity of the walls. With regard to the strengthened walls, based on the experimental results of this thesis, both the FRP sheets and the four different configurations with steel elements appeared to lead to improved behavior in terms ductility values, mainly due to the limitation of the buckling of the compressive longitudinal rebars. Secondary, the control of the web shear cracking (either with horizontal strips or diagonal angles) appeared to lead to hysteretic cycles with less pinching effects and therefore to higher energy dissipation values and also to lower shear deformation values. The assessment of the behavior of the walls was carried out with two different approaches. Firstly, by applying the analytical/empirical relations included in Eurocode 8 - Part 3, which appeared to lead to conservative values, especially with regard to the shear strength, and secondly, by using two different linear beam elements included in OpenSees library for Non-Linear Analysis: the Force-Based BeamColumn Element (FBE) which is a flexural element and the Flexure-Shear Interaction DisplacementBased Beam-Column Element (FSI) that additionally incorporates the influence of the shear component. As found during the analysis process, the flexural element FBE generally approaches with sufficient precision the failure displacement in cases of adequately reinforced walls against shear, while especially in cases of intense buckling of the compressive rebars with simultaneous absence of concrete confinement, the analysis with FBE led to descending post-yield branches, something which was also experimentally observed. In contrast, in the case of insufficiently reinforced walls against shear, the use of FSI approaches better the shear degradation as the ductility increases. However, in cases of low shear reinforcement ratioσ, FSI led to a large underestimation of the shear (and of the total) strength and therefore to severely descending post-yield branches, something which was not experimentally confirmed.Αντικείμενο της διατριβής είναι η πειραματική και αριθμητική/αναλυτική μελέτη της συμπεριφοράς υποωπλισμένων τοιχωμάτων από σκυρόδεμα, τα οποία χαρακτηρίζονται από την απουσία διαμόρφωσης ακραίων κρυφοϋποστυλωμάτων και μικρά ποσοστά διατμητικού οπλισμού, αλλά και η αποτίμηση διαφορετικών διαμορφώσεων ενίσχυσης αυτών. Η πειραματική διαδικασία περιελάμβανε την πειραματική δοκιμή 16 συνολικά τοιχίων-δοκιμίων μεσαίας λυγηρότητας (οκτώ μη ενισχυμένων, επτά ενισχυμένων και ενός επισκευασμένου/ενισχυμένου), τα οποία μελετήθηκαν ως πρόβολοι υπό στατική ανακυκλιζόμενη φόρτιση. Όσον αφορά τους τρόπους ενίσχυσής τους εξετάστηκε η εφαρμογή υφάσματος (μανδύα) Ινοπλισμένων Πολυμερών (ΙΟΠ) και η εφαρμογή μεταλλικών στοιχείων (ελασμάτων και γωνιών). Όπως προέκυψε από την πειραματική δοκιμή των μη ενισχυμένων τοιχίων η αστοχίας τους συνδέεται σε όλες τις περιπτώσεις με την αστοχία της θλιβόμενης ζώνης η οποία επιταχύνεται από τον λυγισμό των θλιβόμενων ράβδων. Όσον αφορά τον διατμητικό οπλισμό αυτός φάνηκε να επηρεάζει περισσότερο το εύρος της ρηγμάτωσης του κορμού και, επομένως, τις τιμές απορρόφησης ενέργειας και τις διατμητικές παραμορφώσεις και λιγότερο την φέρουσα ικανότητα των τοιχίων. Όσον αφορά τα ενισχυμένα τοιχία, με βάση τα πειραματικά αποτελέσματα της συγκεκριμένης διατριβής, τόσο η ενίσχυση με μανδύα ΙΟΠ όσο και ενίσχυση με τέσσερις διαφορετικές διαμορφώσεις με μεταλλικά στοιχεία (ελάσματα και γωνίες), φάνηκε να οδηγεί σε βελτιωμένη συμπεριφορά όσον αφορά την δυνατότητα ανάπτυξης υψηλότερων τιμών πλαστιμότητας κυρίως λόγω του περιορισμού του λυγισμού των θλιβόμενων διαμήκων ράβδων. Δευτερευόντως, ο έλεγχος των διατμητικών ρωγμών του κορμού (είτε με οριζόντια ελάσματα είτε με χιαστί γωνίες) φάνηκε να οδηγεί σε κύκλους υστέρησης με μικρότερο στένωμα και επομένως σε μεγαλύτερες τιμές απορρόφησης ενέργειας αλλά και μικρότερες τιμές διατμητικών παραμορφώσεων. Η θεωρητική αποτίμηση/πρόβλεψη της συμπεριφοράς των τοιχίων πραγματοποιήθηκε με δύο διαφορετικές προσεγγίσεις. Πρώτον, με την εφαρμογή των αναλυτικών/εμπειρικών σχέσεων που περιλαμβάνονται στον Ευρωκώδικα 8 – Μέρος 3 οι οποίες φάνηκαν να οδηγούν σε συντηρητικές τιμές κυρίως όσον αφορά την διατμητική αντοχή και δεύτερον, με την χρήση δύο διαφορετικών γραμμικών πεπερασμένων στοιχείων (beam elements) που περιλαμβάνονται στην βιβλιοθήκη του λογισμικού OpenSees για μη γραμμική ανάλυση: το Force-Based Beam-Column Element (FBE) το οποίο είναι ένα καμπτικό στοιχείο και το Flexure-Shear Interaction Displacement-Based Beam-Column Element (FSI) το οποίο ενσωματώνει επιπροσθέτως την επιρροή της διατμητικής συνιστώσας. Όπως διαπιστώθηκε κατά την διαδικασία της ανάλυσης το καμπτικό στοιχείο FBE γενικά προσεγγίζει με ικανοποιητική ακρίβεια την μετακίνηση αστοχίας στις περιπτώσεις επαρκώς ωπλισμένων τοιχίων έναντι διάτμησης ενώ, ειδικότερα στις περιπτώσεις έντονου λυγισμού των θλιβόμενων ράβδων με ταυτόχρονη απουσία περισφιγμένου σκυροδέματος, η ανάλυση με FBE οδήγησε σε έντονα φθιτούς μετελαστικούς κλάδους κάτι το όποιο παρατηρήθηκε και πειραματικά. Αντίθετα, στην περίπτωση των μη επαρκώς ωπλισμένων τοιχίων έναντι διάτμησης η χρήση του FSI προσεγγίζει καλύτερα την μικρή απομείωση της αντοχής στις μετελαστικές μετακινήσεις (shear degradation). Ωστόσο, στις περιπτώσεις πολύ μικρών ποσοστών διατμητικού οπλισμού το FSI οδήγησε σε μεγάλη απομείωση της διατμητικής (και επομένως της συνολικής) αντοχής και σε έντονα φθιτούς κλάδους κάτι το οποίο δεν επιβεβαιώθηκε πειραματικά

Recommender systems with probabilistic topic models

This doctoral thesis is positioned in the research area of decision support systems and specifically in recommender systems. It focuses on the design and development of recommender systems based on probabilistic topic models.In this thesis we have thoroughly examined the literature related to utilizing machine learning techniques and probabilistic latent semantic analysis for providing recommendations. We explore the possibility to design improved recommender systems inside enterprises, communities and in electronic commerce based on latent topics.An approach is presented for integrating existing domain knowledge in a recommender system. Additionally, a methodology is proposed for utilizing probabilistic topic models for complete and effective modeling of employee expertise on addressing problems. A methodology is described for extracting consumer preferences from datasets using topic models. Finally, we present and evaluate a methodology for utilizing the unstructured text found in electronic auction marketplaces in order to provide recommendations to buyers and sellers. The recommender systems proposed in this thesis have displayed a number of common characteristics: 1)They reduce the dimensions of the recommendation problem and provide fast online recommendations, having trained the topic models.2)They satisfy the user needs for accuracy and recall of all interesting objects.3)The topics extracted can provide significant insight to the system manager or owner.H διδακτορική διατριβή τοποθετείται στον χώρο των συστημάτων αποφάσεων και ειδικότερα στην περιοχή των συστημάτων προτάσεων (recommender systems) όπου προτείνει την ανάπτυξη συστημάτων προτάσεων με χρήση πιθανοτικών μοντέλων θεμάτων (probabilistic topic models).Στο πλαίσιο της διατριβής πραγματοποιήθηκε βιβλιογραφική μελέτη στα γνωστικά πεδία της χρήσης τεχνικών μηχανικής μάθησης και της πιθανοτικής λανθάνουσας σημασιολογικής ανάλυσης (probabilistic latent semantic analysis) για την πραγματοποίηση προτάσεων. Στην παρούσα διατριβή διερευνάται η δυνατότητα για βελτιωμένα συστήματα προτάσεων στο εσωτερικό επιχειρήσεων, κοινοτήτων και στο εμπόριο με βάση λανθάνοντα θέματα.Παρουσιάζεται μία προσέγγιση για την ενσωμάτωση της υπάρχουσας γνώσης ενός πεδίου σε ένα σύστημα προτάσεων. Ακόμη, προτείνεται μια μεθοδολογία που εκμεταλλεύεται την εξαγωγή πιθανοτικών μοντέλων θεμάτων για την πλήρη και αποτελεσματική μοντελοποίηση της ικανότητας ενός εργαζομένου να αντιμετωπίσει ένα πρόβλημα. Περιγράφεται μια μεθοδολογία εξαγωγής προτιμήσεων για καταναλωτές σε υπεραγορές από ένα σύνολο δεδομένων με χρήση λανθανόντων θεμάτων. Τέλος, προτείνεται και αξιολογείται μια μεθοδολογία για την εκμετάλλευση του μη δομημένου κειμένου που βρίσκεται σε ηλεκτρονικές αγορές δημοπρασιών για την παραγωγή προτάσεων που απευθύνονται σε αγοραστές και πωλητές.Τα συστήματα προτάσεων που προτείνονται αξιολογήθηκαν με ενθαρρυντικά αποτελέσματα και παρουσίασαν κοινά χαρακτηριστικά: (1) μειώνουν τις διαστάσεις του προβλήματος και παρέχουν γρήγορα προτάσεις αφού έχει προηγηθεί η εξαγωγή των μοντέλων θεμάτων, (2) ικανοποιούν τις απαιτήσεις των χρηστών για ακρίβεια και ανάκληση των δεδομένων που τους ενδιαφέρουν, (3) τα θέματα που εξάγονται μπορούν να αποτελέσουν σημαντική πληροφορία για τον ιδιοκτήτη ή τον διαχειριστή του συστήματος