Analysis and Modeling of Motor Vehicle Crashes Involving Air Force Military Personnel

The primary purpose of this thesis was to improve the data analysis of Motor Vehicle Crashes (MVCs). This thesis employed the Air Force Safety Center (AFSC) data, collected over 20 years, of MVCs in which US Air Force (USAF) military personnel are involved when off duty and off base. Categorical Data Analysis and Analysis of Variance (ANOVA) were applied to identify risk factors related to MVCs and influence the severity of injuries and those factors associated with the alcohol consumption before driving, and affect the number of lost workdays resulting from MVCs. Categorical Data Analysis showed that male USAF members aged 17-24 years or with the rank of Airman were more prone to experience a fatal MVC. Moreover, fatal MVCs peaked between the hours of 2200 pm to 0559 am, and USAF female drivers seemed to wear seatbelts more than USAF male drivers. These thesis results revealed the value of wearing seatbelts for the prevention of severe injuries during crashes. Finally, ANOVA results exposed that the more severe the Type of Injury, the greater the number of Lost Days and that 2-wheeled vehicle MVCs have the most significant effect on the number of Lost Days

Ανάπτυξη και μελέτη αγώγιμων διαφανών υμενίων ZnO

Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Μικροσυστήματα και Νανοδιατάξεις

Το Crowdsourcing και η συμβολή του στην διαδικασία λήψης απόφασης σε μία εταιρεία ή οργανισμό

To Crowdsourcing ή πληθοπορισμός είναι ένας σχετικά νέος όρος ο οποίος αναφέρεται στην αξιοποίηση της δυναμικής ενός πληθυσμού από έναν οργανισμό. Η έρευνα ξεκίνησε με την επισκόπηση των διαφόρων τύπων του crowdsourcing. Εντοπίστηκαν δύο τύποι crowdsourcing οι οποίοι σχετίζονται με τις καινοτομίες που παράγουν. Υπάρχουν δηλαδή είδη έρευνας όπου το πλήθος χρησιμοποιείται για να παραχθούν καινοτόμες ιδέες (crowdsourcing creative tasks) ή να παρέχουν λύσεις σε προβλήματα (crowdsourcing complex tasks). Μέχρι τώρα υπήρχε ελάχιστη γνώση σχετικά με τα χαρακτηριστικά της διαδικασίας για τη συγκέντρωση ιδεών από το πλήθος. Ως εκ τούτου, η έρευνα αυτή ανέλαβε να διερευνήσει και να ταξινομήσει τα χαρακτηριστικά της διαδικασίας για τους δύο τύπους του crowdsourcing. Το ακόλουθο ερώτημα της έρευνας διατυπώθηκε ως εξής: ΄΄ Πώς τα χαρακτηριστικά της διαδικασίας του crowdsourcing συμβάλουν στα αποτελέσματα των crowdsourcing creative και complex tasks και πόσο αυτά επηρεάζουν την διαδικασία λήψης αποφάσεων σε μια υπηρεσία ή έναν Οργανισμό; ΄΄ Για να απαντήσουμε σε αυτό το ερώτημα, ακολουθήθηκε μία πρωτοβουλία εφαρμογής μελέτης crowdsourcing μέσω συνεντεύξεων και αντλήθηκαν στοιχεία σχετικά με το είδος και το περιβάλλον εργασίας της κάθε επιχείρησης. Με τη χρήση Ποιοτικής Συγκριτικής Ανάλυσης (ΠΣΑ), καθορίστηκε η διαμόρφωση των χαρακτηριστικών της διαδικασίας. Το αποτέλεσμα της υπολογίστηκε βάσει μεταβλητών όπως η ποσότητα, η ποικιλία και η χρηστικότητα των πληροφοριών που συλλέχθηκαν. Τα ευρήματα έδειξαν ότι η χρονική διάρκεια για την παροχή ανατροφοδότησης και ο βαθμός της αλληλεπίδρασης των ερωτηθέντων επηρέασε την ποιότητα των δεδομένων. Επιπρόσθετα η ιδιαιτερότητα του κάθε ερωτήματος σε συνδυασμό με το μέγεθος της αλληλεπίδρασης βρέθηκαν να επηρεάζουν τόσο την ποικιλία όσο και τη χρηστικότητα των παρεχόμενων πληροφοριών. Με αυτόν τον τρόπο ανακαλύφθηκαν οι σημαντικές διαφορές μεταξύ των δύο τύπων του crowdsourcing. Επιπλέον, με βάση τα στοιχεία από τις συνεντεύξεις και την βοήθεια της ακαδημαϊκής βιβλιογραφίας, δόθηκαν πιθανές εξηγήσεις για αυτές τις διαμορφώσεις, και προτάσεις για την μελλοντική χρήση τέτοιας μορφής δεδομένων στην λήψη αποφάσεων.Crowdsourcing is a relatively new term that refers to the use of the dynamics of a population in work place. Our investigation began with an overview of the different types of crowdsourcing. There are two types of crowdsourcing that are associated with the innovations they produce. There are research areas where the crowd is used to generate innovative ideas (crowdsourcing creative tasks) or provide solutions to problems (crowdsourcing complex tasks). Until now there was little knowledge about the characteristics of the crowdsourcing process. Therefore, the investigation was undertaken to investigate and classify the characteristics of the process for both types of crowdsourcing. The following research question was formulated as follows: How the characteristics of the crowdsourcing process contribute to the results of crowdsourcing creative and complex tasks and how they affect the decision-making process to an enterprise or an organization? To answer this question, a crowdsourcing case study was made, gathering data from interviews, questionnaires and general information about the type and the interface of seven different enterprises and organizations. Using Qualitative Comparative Analysis (QCA), the configuration of the features of the process was determined. The result was based on variables such as the amount, variety and usability of the collected information. The findings showed that the time to provide feedback and the degree of interaction of respondents affected the quality of data. In addition, the specificity of each question in conjunction with the size of the interaction was found to affect the range and the usability of the provided information. Thus we discovered significant differences between the two types of crowdsourcing. Furthermore, based on the interviews data from and the help of academic literature we tried to give possible explanations for these configurations, and suggestions for the future use of such data in order to generate accurate and productive decisions

Selection of co-belonging ceramic fragments from archaeological excavations and their location in vase bodies from thermoremanent magnetization

Summarization: Selection of co-belonging fragments fromthe numerous ceramic findings of an archaeological excavation based exclusively on the experience and patience of the conservators remains a difficult process of questionable effectiveness. While the screening of the fragments is a central prerequisite and the most important stage of the process of vase reconstruction, established methods based on scientific criteria and guaranteed efficiency for the detection of co-belonging ceramic fragments suggested in the bibliography do not exist. On the contrary, for methods dealing with the assembly of vases from co-belonging fragments, which is a secondary process that can be done more easily and effectively in an empirical way, there exist numerous studies based on fragment morphology. However, even these are also not implemented because of the time requirements, sheer volume and complexity of the proposed methods, in order for them to be applicable in practice. The proposed methods in this paper are based on thermoremanent magnetization (A/m), which is calculated from the weak magnetic field measurements by a fluxgate-sensor/magnet apparatus forming a three-dimensional orthogonal system. Experimental measurements from fragments of six vases show that the magnetization magnitude of co-belonging fragments display similar values, despite the magnetic anisotropy of the ceramic material, since these belong to vases made of the same clay and fired under the same conditions. This is the criterion for finding ceramic fragments of the same vase from archaeological excavations. The thermoremanent magnetism directionality of fragments, which is aligned along the geomagnetic field at the same place and time during the vase firing process, as it is configured by their rotational symmetry, defines the position of the fragments on the body of the six vases. The shape of the original vase can be reconstructed when only a few non adjacent fragments are available. The proposed measurement apparatus can be used for the construction of a useable portable magnetometer specialized for ceramic surface measurements to achieve the above objectives.Παρουσιάστηκε στο: Applied Sciences (Switzerland

The burden and management of anemia in Greek patients with inflammatory bowel disease: a retrospective, multicenter, observational study

Background: Anemia is a common extraintestinal manifestation of Inflammatory Bowel Disease (IBD) affecting negatively the patients’ quality of life. The aim of this study was to determine the frequency and real-life management of anemia in IBD patients in Greece. Methods: This study was conducted in 17 Greek IBD referral centers. Demographic, clinical, laboratory, IBD and anemia treatment data were collected and analyzed retrospectively. Results: A total of 1394 IBD patients [560 ulcerative colitis (UC), 834 Crohn’s disease (CD)] were enrolled. Anemia at any time was reported in 687 (49.3%) patients of whom 413 (29.6%) had episodic and 274 (19.7%) had recurrent/persistent anemia. Anemia was diagnosed before IBD in 45 (6.5%), along with IBD in 269 (39.2%) and after IBD in 373 (54.3%) patients. In the multivariate analysis the presence of extraintestinal manifestations (p = 0.0008), IBD duration (p = 0.026), IBD related surgeries and hospitalizations (p = 0.026 and p = 0.004 accordingly) were risk factors of recurrent/persistent anemia. Serum ferritin was measured in 839 (60.2%) IBD patients. Among anemic patients, 535 (77.9%) received treatment. Iron supplementation was administered in 485 (90.6%) patients, oral in 142 (29.3%) and intravenous in 393 (81%). Conclusions: The frequency of anemia in IBD patients, followed at Greek referral centers, is approximately 50%. Development of recurrent/persistent anemia may be observed in 20% of cases and is independently associated with the presence of extraintestinal manifestations, IBD duration, IBD related surgeries and hospitalizations. Anemia treatment is administered in up to [Formula: see text] of anemia IBD patients with the majority of them receiving iron intravenously