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Geographically Differentiated NGA Deployment
Get PDFThis paper studies the incentives of an unregulated monopolist to undertake the socially optimal investment in NGA networks when it takes into account the fact that the NGA deployment is a two-dimensional investment decision concerning both the quality (or equivalently, technology) and the geographic coverage. It is found that both the privately and the socially optimal investment decisions result in a geographically differentiated NGA deployment implying that different quality NGA networks are deployed in different geographic areas. In particular, NGA networks of higher (lower) quality are deployed in the more (less) densely populated geographic areas. Although such geographically differentiated NGA investment leads the monopolist to provide a nationwide NGA deployment, it is found that the monopolist underinvests compared to the socially optimal levels of both technology and geographic coverage. In addition, since the objectives of the Europe 2020 Strategy concern both the NGA technology and the NGA coverage, this paper shows that the first objective of providing all Europeans with access to much higher internet speeds of above 30 Mbps is feasible when the demand for NGA-based services is significantly elastic, whereas the second objective of providing internet connection speeds of 100 Mbps to 50% or more of European households is not a feasible goal
Autopilot spatially-adaptive active contour parameterization for medical image segmentation
Get PDFIn this work, a novel framework for automated, spatially-adaptive adjustment of active contour regularization and data fidelity parameters is proposed and applied for medical image segmentation. The proposed framework is tailored upon the isomorphism observed between these parameters and the eigenvalues of diffusion tensors. Since such eigenvalues reflect the diffusivity of edge regions, we embed this information in regularization and data fidelity parameters by means of entropy-based, spatially-adaptive `heatmaps'. The latter are able to repel an active contour from randomly directed edge regions and guide it towards structured ones. Experiments are conducted on endoscopic as well as mammographic images. The segmentation results demonstrate that the proposed framework bypasses iterations dedicated to false local minima associated with noise, artifacts and inhomogeneities, speeding up contour convergence, whereas it maintains a high segmentation quality
Διαχρονική αξιολόγηση της φυσικής δραστηριότητας και των καθιστικών συνηθειών σε μαθητές/τριες, ηλικίας 11-12 ετών.
Get PDFEnvironmental Impact Assessment of the Life Cycle of a Timber Building
Get PDFTimber construction offers a number of advantages in terms of sustainability in comparison with other construction technologies. This can partly be attributed to the fact that structural timber products often require less processing for their manufacturing compared to other construction products and their sustainability is therefore relatively increased. As a result, structures such as timber buildings are associated with increased sustainability potential and are therefore selected as sustainable solutions for the construction of housing, commercial or other types of building projects. The current research, described in this paper, is aimed at the quantification of the environmental impact caused by the construction of timber buildings. A case study is used as the basis for the calculations which take into account the whole life cycle of the timber building examined. A life cycle assessment is conducted and the environmental impact assessment results are calculated according to the Eco-Indicator 99 methodology. The interpretation of the results leads to conclusions regarding the level and type of environmental impact caused by the life cycle of timber building projects
Comparative genomics of Streptococcus macedonicus ACA-DC 198 against related species within the Streptococcus bovis/Streptococcus equinus complex
Get PDFApart from Streptococcus thermophilus other streptococci that can be found growing in milk belong to the Streptococcus bovis/Streptococcus equinus complex (SBSEC). Interestingly, Streptococcus macedonicus, which is a member of SBSEC, has been suggested to be adapted to milk and to be nonpathogenic. However, the species is phylogenetically related to Streptococcus gallolyticus and Streptococcus pasteurianus (formerly known as S. bovis biotypes I and II.2, respectively), which in turn are considered pathogenic, since they have been implicated in endocarditis and colon cancer in humans. Comparative analysis of the S. macedonicus genome with the complete genomes of its related streptococci (including that of S. infantarius, which is also a dairy isolate) indicated that a significant portion of the genomic organization has been conserved overall. Following a gene presence/absence strategy, we determined that S. macedonicus shows a reduced capacity to reside in the gastrointestinal tract of ruminants when compared to S. gallolyticus since it misses important genes for metabolizing complex carbohydrates of plant origin and for detoxifying this environment. S. macedonicus also lacks several pathogenicity traits found in S. gallolyticus. For example from the three pilus gene clusters (pil1, pil2, pil3), which may mediate the binding of S. gallolyticus to the extracellular matrix, S. macedonicus carries only one (i.e. the pil3). Gene gain events are also evident in the S. macedonicus genome sometimes originating from dairy bacteria, like the acquisition of the lactococcal plasmid pSMA198. Functional analysis of the S. macedonicus genome is necessary to further assess its pathogenic and technological potential
Επίδραση της σκίασης στην ανάπτυξη, παραγωγή και ποιότητα του άνηθου (Anethum graveolens L.) [Παρουσίαση]
No full textΗ παρούσα εργασία πραγματοποιήθηκε με σκοπό τον προσδιορισμό της κατάλληλης σκίασης για την καλλιέργεια του άνηθου (Anethum graveolens L. cv. Ducat) κατά τους θερινούς μήνες. Εφαρμόστηκαν τρεις μεταχειρίσεις: (1) χωρίς σκίαση, (2) κάλυψη των φυτών με δίχτυ σκίασης 30% και (3) 70%. Η κάλυψη των φυτών με δίκτυ σκίασης 30 ή 70% είχε θετική επίδραση στην ανάπτυξη και την παραγωγή των φυτών (ύψος και νωπό βάρος των φυτών, αριθμός φύλλων) αλλά αύξησε το ποσοστό των φυτών που άνθησαν. Παράλληλα, η σκίαση προκάλεσε αύξηση στη συγκέντρωση χλωροφύλλης στα φύλλα, χωρίς να επηρεάσει τη συγκέντωση φαινολικών και καροτενοειδών. Η συγκέντρωση της βιταμίνης C δεν επηρεάστηκε από τη σκίαση 30%, αλλά μειώθηκε στη σκίαση 70%. Η περιεκτικότητα σε νάτριο και χλώριο μειώθηκε στα φυτά υπό σκίαση σε σχέση με το μάρτυρα. Αντίθετα, η περιεκτικότητα των φύλλων σε κάλιο αυξήθηκε στα φυτά υπό σκίαση 70%. Συνεπώς, παρόλη την αύξηση της άνθησης η κάλυψη των φυτών με δίκτυ σκίασης ενδείκνυται για την παραγωγή του άνηθου κατά τη θερινή περίοδο
Ετήσια Έκθεση Προόδου Υποέργου: Από έναρξη υποέργου έως και 31/12/2013
Get PDFΗ παρούσα ετήσια έκθεση αφορά το υποέργο με τίτλο «ΕΙΚΟΣ: Θεωρητική Και Αλγοριθμική Θεμελίωση για Προσωποκεντρικά Συνεργατικά Πληροφοριακά Συστήματα» που υλοποιείται στο Ινστιτούτο Πληροφοριακών Συστημάτων του Ερευνητικού Κέντρου «ΑΘΗΝΑ». Η έκθεση αφορά το χρονικό διάστημα από την έναρξη του υποέργου μέχρι και την 31/12/20013. Ο σκοπός της έκθεσης αυτής είναι κατ’ αρχήν η συγκεντρωτική παρουσίαση της προόδου του υποέργου στο διάστημα 1/2/2012 ως και 31/12/2013. Επιπλέον, περιγράφονται οι μελλοντικές προοπτικές και τα επόμενα βήματα για το 2014
Effects of 5-lipoxygenase pathway inhibition on rhinovirus-associated bronchial epithelial inflammation
Get PDFSystematic optimization of the storage capacity of slow light photonic crystal waveguides
Get PDFA systematic design process of slow light photonic crystal slab waveguides is presented with the aim of maximizing the storage capacity. Dispersion effects and propagation losses characteristics are included in order to increase the design accuracy. Our procedure allows the optimization of the structure at the same time by varying as many as ten design parameters. We show that storage capacities of almost 32bits at 40Gb/s and 65bits at 100Gb/s can be obtained