Natural language processing methods for the greek language on pattern recognition of learning and behavior in virtual learning communities: bullying behavior and suicidal ideation

Aggressive behavior has become a major social problem concerning sensitive groups, such as children and adolescents. It occurs mainly in two different types: aggression "towards the other" and aggression "towards the self". The first type refers mainly to bullying, while the second one refers to suicidal ideation. Early detection of both types of aggressive behavior is crucial for timely intervention. Nowadays, various activities are transferred from real world to the digital one. Consequently, bullying acquires its digital form, cyberbullying. Accordingly, suicidal behavior is transformed into cyberbullicide. At the same time, online collaborative learning environments have been developed, transferring learning processes to the digital world. As a result, transition of Physical Learning Communities (PLCs) to the digital world, as Virtual Learning Communities (VLCs), includes the risk of aggressive behavior. The development of Computational Linguistics' applications has led to the creation of models, aiming at the automatic detection of aggressive behavior, especially in the digital world, where physical supervision is particularly difficult. Research so far has provided promising results, but it is limited to the social media context and it has not been applied to the Greek language. In the present dissertation, the aggressive behavior in the field of VLCs has been studied and analyzed. For this purpose, five (5) case studies (CS) were created, which were designed methodologically as a collective CS. An analysis, based on the collaborative process, the role of the teacher and the inner speech, was applied on the collected data (dialogues and artifacts). Suicidal ideation was also analyzed using linguistic data drawn from modern Greek poetry. Models, aiming to identify both types of aggressive behavior using Natural Language Processing (NLP) and machine learning methods, were applied to linguistic data of different types, providing promising results. Application of these models in VLCs' data and in the Greek language is the main contribution of this dissertation.Η επιθετική συμπεριφορά έχει εξελιχθεί σε ένα μείζον κοινωνικό πρόβλημα που αφορά και ευαίσθητες ομάδες, όπως είναι τα παιδιά και οι νέοι. Εκδηλώνεται κυρίως με δύο διαφορετικούς τύπους: την επιθετικότητα "προς τον άλλο" και την επιθετικότητα "προς τον εαυτό". Η πρώτη μορφή εκδηλώνεται κυρίως μέσω του εκφοβισμού, ενώ η δεύτερη μέσω του αυτοκτονικού ιδεασμού. Ο έγκαιρος εντοπισμός και των δύο τύπων επιθετικής συμπεριφοράς είναι ιδιαίτερα κρίσιμος για την έγκαιρη παρέμβαση και την αντιμετώπιση σχετικών περιστατικών. Στη σύγχρονη εποχή πλείστες δραστηριότητες μεταφέρονται από τον πραγματικό στον ψηφιακό κόσμο. Έτσι, και ο εκφοβισμός (bullying) αποκτά και ψηφιακή υπόσταση (cyberbullying). Ομοίως, και η αυτοκτονική συμπεριφορά (suicide) μεταφέρεται σε διαδικτυακά περιβάλλοντα (cyberbullicide). Την ίδια στιγμή έχουν αναπτυχθεί διαδικτυακά συνεργατικά περιβάλλοντα μάθησης, μεταφέροντας μέρος των μαθησιακών διαδικασιών στον ψηφιακό κόσμο. Ως επακόλουθο, η μεταφορά Φυσικών Κοινοτήτων Μάθησης (ΦΚΜ) στον ψηφιακό κόσμο, ως Δυνητικές Κοινότητες Μάθησης (ΔΚΜ), εμπεριέχει τον κίνδυνο εμφάνισης επιθετικής συμπεριφοράς. Η ανάπτυξη εφαρμογών Γλωσσικής Τεχνολογίας έχει οδηγήσει στη δημιουργία μοντέλων αυτόματου εντοπισμού της επιθετικής συμπεριφοράς, κυρίως στον ψηφιακό κόσμο, όπου η φυσική εποπτεία είναι ιδιαίτερα δύσκολη. Η μέχρι τώρα έρευνα έχει αποφέρει ελπιδοφόρα αποτελέσματα, περιορίζεται όμως στο περιβάλλον των κοινωνικών δικτύων (social media), χωρίς εφαρμογή για την ελληνική γλώσσα. Στην παρούσα διατριβή μελετήθηκε και αναλύθηκε η επιθετική συμπεριφορά στο πεδίο των ΔΚΜ. Για το σκοπό αυτό δημιουργήθηκαν πέντε (5) διακριτές μελέτες περίπτωσης (ΜΠ), που αντιμετωπίστηκαν μεθοδολογικά ως μια συλλογική ΜΠ. Στα δεδομένα που συλλέχθηκαν (διάλογοι και τεχνουργήματα) εφαρμόστηκε ανάλυση με κύριους άξονες τη συνεργατικότητα, το ρόλο του/της δασκάλου/-ας και τον εσωτερικό λόγο. Αναλύθηκε επίσης και ο αυτοκτονικός ιδεασμός με χρήση γλωσσολογικών δεδομένων, τα οποία αντλήθηκαν από τη νεοελληνική ποίηση. Δημιουργήθηκαν μοντέλα εντοπισμού και των δύο τύπων επιθετικής συμπεριφοράς με χρήση μεθόδων Επεξεργασίας Φυσικής Γλώσσας (Natural Language Processing-NLP) και Μηχανικής Μάθησης, τα οποία εφαρμόστηκαν σε γλωσσολογικά δεδομένα διαφορετικού ύφους αποφέροντας ελπιδοφόρα αποτελέσματα. Η εφαρμογή των μοντέλων αυτών, σε δεδομένα ΔΚΜ και στην ελληνική γλώσσα, αποτελεί την κύρια συνεισφορά της διατριβής

The difference between reported and real-world CO2 emissions: How much improvement can be expected by WLTP introduction?

The monitoring and reporting of CO2 emissions of light duty vehicles in Europe and other major markets is based on the New European Driving Cycle and the accompanying test protocol. This procedure has been proven non-representative of real world vehicle operation, fuel consumption and CO2 emissions leading to a gap between officially reported emissions and the ones experienced during real world operation. This gap is reported to be increasing with time. To address this issue and improve the certification procedure for pollutant emissions of vehicles over real driving, the new Worldwide Harmonized Light duty vehicle Test Protocol was designed. This new test procedure is expected to provide more realistic emission and fuel consumption results. In this paper a first estimate of the certification-reality gap under the present (2015) conditions is attempted and the impact of the new test procedure is investigated. Tests were performed on three real vehicles over the two cycles which allowed the development of representative simulation models. A detailed simulation matrix was subsequently formulated, taking into account the two tests and expected conditions occurring during real world driving. Results show that for 2013-14 model year European passenger cars the difference in certified and actually emitted CO2 emissions for an average European passenger car reaches up to 40 g CO2/km (~32% higher than certification). WLTP introduction is expected to improve the picture, however a shortfall of about 10-15% between official and real world may remain.JRC.C.4-Sustainable Transpor

The development of the World-wide Harmonized Test Procedure for Light Duty Vehicles (WLTP) and the pathway for its implementation into the EU legislation

In order to assess vehicle performances in terms of criteria compounds, CO2 emissions and fuel/energy consumption, laboratory tests are mainly carried out. During these tests a vehicle is driven on a chassis dynamometer (which simulates the resistances the vehicle encounters during its motion) to follow a predefined test-cycle. In addition, all the conditions to run a test must strictly adhere to a predefined test-procedure. This is necessary to ensure that all the tests are carried out in a comparable way, following the requirement set by the relevant legislation. Test results are indeed used to assess the vehicle compliance with respect to, e.g., emission limits or to evaluate the fuel consumption that will be communicated to the customers. Any region in the world follows its own approach to carry out these types of tests. This has a series of drawbacks for both vehicle manufacturers and regulating authorities, leading in any case to a plethora of different conditions and results. In order to make a step towards the harmonization of the different test-procedures, the United Nations Economic Commission for Europe (UNECE) in 2009 launched a project for the development of a World-wide harmonized Light duty Test Procedure (WLTP), including also a new test cycle. Objective of the present paper is to provide a brief description of the WLTP and to outline the possible pathway for its introduction in the European Legislation

Development of World-Wide Harmonized Test Procedure for Light-Duty Vehicles: Pathway for Implementation in European Union Legislation

To assess vehicle performance on criteria compounds, carbon dioxide emissions, and fuel energy consumption, laboratory tests are generally carried out. During these tests, a vehicle is driven on a chassis dynamometer (which simulates the resistances the vehicle encounters during its motion) to follow a predefined test cycle. In addition, all conditions for running a test must strictly adhere to a predefined test procedure. The procedure is necessary to ensure that all tests are carried out in a comparable way, following the requirements set by the relevant legislation. Test results are used to assess vehicle compliance with emissions limits or to evaluate the fuel consumption that will be communicated to customers. Every region in the world follows its own approach in carrying out these types of tests. The variations in approaches have resulted in a series of drawbacks for vehicle manufacturers and regulating authorities, leading to a plethora of different conditions and results. As a step toward the harmonization of the test procedures, the United Nations Economic Commission for Europe launched a project in 2009 for the development of a worldwide harmonized light-duty test procedure (WLTP), including a new test cycle. The objective of the study reported here was to provide a brief description of WLTP and outline the plausible pathway for its introduction in European legislation.JRC.F.8-Sustainable Transpor

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)

Search for Scalar Diphoton Resonances in the Mass Range 65−60065-600 GeV with the ATLAS Detector in pppp Collision Data at s\sqrt{s} = 8 TeVTeV

A search for scalar particles decaying via narrow resonances into two photons in the mass range 65–600 GeV is performed using $20.3\text{}\text{}{\mathrm{fb}}^{-1}$ of $\sqrt{s}=8\text{}\text{}\mathrm{TeV}$ $pp$ collision data collected with the ATLAS detector at the Large Hadron Collider. The recently discovered Higgs boson is treated as a background. No significant evidence for an additional signal is observed. The results are presented as limits at the 95% confidence level on the production cross section of a scalar boson times branching ratio into two photons, in a fiducial volume where the reconstruction efficiency is approximately independent of the event topology. The upper limits set extend over a considerably wider mass range than previous searches