Το αντίστροφο πρόβλημα της εύρεσης τηςσΣύστασης δερματικού ιστού

Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Εφαρμοσμένες Μαθηματικές Επιστήμες

Development and application of artificial neural network models to estimate values of a complex human thermal comfort index associated with urban heat and cool island patterns using air temperature data from a standard meteorological station

© 2018, ISB. The present study deals with the development and application of artificial neural network models (ANNs) to estimate the values of a complex human thermal comfort-discomfort index associated with urban heat and cool island conditions inside various urban clusters using as only inputs air temperature data from a standard meteorological station. The index used in the study is the Physiologically Equivalent Temperature (PET) index which requires as inputs, among others, air temperature, relative humidity, wind speed, and radiation (short- and long-wave components). For the estimation of PET hourly values, ANN models were developed, appropriately trained, and tested. Model results are compared to values calculated by the PET index based on field monitoring data for various urban clusters (street, square, park, courtyard, and gallery) in the city of Athens (Greece) during an extreme hot weather summer period. For the evaluation of the predictive ability of the developed ANN models, several statistical evaluation indices were applied: the mean bias error, the root mean square error, the index of agreement, the coefficient of determination, the true predictive rate, the false alarm rate, and the Success Index. According to the results, it seems that ANNs present a remarkable ability to estimate hourly PET values within various urban clusters using only hourly values of air temperature. This is very important in cases where the human thermal comfort-discomfort conditions have to be analyzed and the only available parameter is air temperature

Analysis of waterspout environmental conditions and of parent-storm behaviour based on satellite data over the southern Aegean Sea of Greece

ABSTRACTA frequent area of waterspout formation is identified over the southern Aegean Sea. The objectives of this study are threefold: (1) to investigate the temporal evolution of Cloud Top Temperature (CTT) of cloud lines (waterspouts' parent clouds) that triggered the formation of single or multiple waterspout events, by using Meteorological Satellite Second Generation infrared satellite data, cloud base height data and weather observations from the closest Hellenic National Meteorological Service meteorological station; (2) to synthesize a detailed climatology of the thermodynamic environment during waterspout activity and (3) to explore the sea‐surface temperature (SST) seasonal distribution and its possible relationships with the temperature of the middle and lower troposphere during waterspout days over the southern Aegean Sea.It was found that the CTT of waterspout parent clouds decreases close to waterspout formation time, which is consistent with growing clouds. The Severe Weather Threat Index (SWEAT), the Bulk Richardson Number (BRN) and the Convective Potential Available Energy during the autumn season were consistent with a shallow‐convection environment. The instability parameter ΔT1000 (difference in the air temperature between 1000 hPa and that at other pressure levels) exhibited a symmetric distribution about the median during both seasons and at all levels. More than 75% of autumn waterspout activity over the southern Aegean Sea developed with SST values varying from 22 to 24.5 °C, while the instability parameter ΔTSST (the temperature difference between the SST and the temperature at various pressure levels) exhibited a symmetrical distribution about the median for both seasons and for all pressure levels, consistent with the ΔT1000 seasonal distribution. A statistical analysis showed that the means of SWEAT, BRN, convective inhibition, SST, ΔTSST and ΔT1000 from air temperature at 700 hPa differ statistically significant (p < 0.001) between waterspout and non‐waterspout days in autumn, over the southern Aegean Sea, during 2005–2012

Transportation and air quality perspectives and projections in a Mediterranean country, the case of Greece

This study provides a thorough review and analysis of the evolution of the Greek vehicle fleet over the last ~30 years, which is next used for the generation of high granularity fleet projections, the assessment of associated air pollution and the estimation of relevant environmental benefits by 2030. The integrated methodology developed takes also into account vehicle clustering and the Brown’s Double Simple Exponential Smoothing technique that, together with the adoption of COPERT-based emission factors, allow for the estimation of the anticipated emissions in 2030. Expected 2030 emissions levels suggest a reduction across all pollutants compared to 2018, ranging from 3.7% for PM10 to 54.5% for NMVOC (and 46% for CO, 14% for SO2, 28% for NOX and 21% for CO2). We find that Greece is on track with national goals concerning the reduction of air pollution from the transportation sector, which designates the positive contribution anticipated by EVs and new, “greener” vehicles, and sets new challenges for the further improvement of the sector beyond the 2030 outlook

Outdoor particulate matter and childhood asthma admissions in Athens, Greece: a time-series study

<p>Abstract</p> <p>Background</p> <p>Particulate matter with diameter less than 10 micrometers (PM₁₀) that originates from anthropogenic activities and natural sources may settle in the bronchi and cause adverse effects possibly via oxidative stress in susceptible individuals, such as asthmatic children. This study aimed to investigate the effect of outdoor PM₁₀concentrations on childhood asthma admissions (CAA) in Athens, Greece.</p> <p>Methods</p> <p>Daily counts of CAA from the three Children's Hospitals within the greater Athens' area were obtained from the hospital records during a four-year period (2001-2004, n = 3602 children). Mean daily PM₁₀concentrations recorded by the air pollution-monitoring network of the greater Athens area were also collected. The relationship between CAA and PM₁₀concentrations was investigated using the Generalized Linear Models with Poisson distribution and logistic analysis.</p> <p>Results</p> <p>There was a statistically significant (95% CL) relationship between CAA and mean daily PM₁₀concentrations on the day of exposure (+3.8% for 10 μg/m³increase in PM₁₀concentrations), while a 1-day lag (+3.4% for 10 μg/m³increase in PM₁₀concentrations) and a 4-day lag (+4.3% for 10 μg/m³increase in PM₁₀concentrations) were observed for older asthmatic children (5-14 year-old). High mean daily PM₁₀concentration (the highest 10%; >65.69 μg/m³) doubled the risk of asthma exacerbations even in younger asthmatic children (0-4 year-old).</p> <p>Conclusions</p> <p>Our results provide evidence of the adverse effect of PM₁₀on the rates of paediatric asthma exacerbations and hospital admissions. A four-day lag effect between PM₁₀peak exposure and asthma admissions was also observed in the older age group.</p

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

THE INFLUENCE OF THE PHYSICOGEOGRAPHICAL FACTORS ON THE AIR TEMPERATURE REGIME OVER GREECE

IN THE PRESENT DISSERTATION THE INFLUENCE OF THE PHYSICOGEOGRAPHICAL FACTORS ONTHE AIR TEMPERATURE REGIME OVER GREECE IS EXAMINED, SO THAT QUALITATIVE AND QUANTITATIVE RELATIONS, BETWEEN THE REASON - PHYSICOGEOGRAPHICAL FACTOR - AND THE RESULT - TEMPERATURE - TO BE GIVEN. THE ABOVE MENTIONED FACTORS SUCH AS THEDISTRIBUTION OF LANDS AND SEAS, THE HEIGHT, THE LATITUDE AND LONGITUDE ARE ANALYSED IN DETAIL, USING CLIMATOLOGICAL ANALYSIS METHODS, AND EFFORTS ARE MADETHE PRESENT STUDY TO BE A USEFUL CONTRIBUTION IN THE RESEARCH OF THE AIR TEMPERATURE REGIME OF GREECE. FROM THE BIG NUMBER OF THE GIVEN IMPORTANT CONCLUSIONS, IT IS MENTIONED THAT THE MOUNTAINS FORM THE TEMPERATURE REGIME OVER THE GREEK AREA JUST AS THE MARCH OF THE VERTICAL LAPSE RATE IS SIMPLE WITH MAXIMUM DURING THE WINTER MONTHS AND MINIMUM DURING THE SUMMER ONES.ΣΤΗΝ ΠΑΡΟΥΣΑ ΔΙΔΑΚΤΟΡΙΚΗ ΔΙΑΤΡΙΒΗ ΜΕΛΕΤΑΤΑΙ ΚΑΙ ΑΝΑΛΥΕΤΑΙ Η ΕΠΙΔΡΑΣΗ ΤΩΝ ΦΥΣΙΚΟΓΕΩΓΡΑΦΙΚΩΝ ΠΑΡΑΓΟΝΤΩΝ ΣΤΟ ΘΕΡΜΟΚΡΑΣΙΑΚΟ ΚΑΘΕΣΤΩΣ ΤΗΣ ΕΛΛΑΔΟΣ, ΩΣΤΕ ΝΑ ΑΝΑΔΕΙΧΘΟΥΝ ΠΟΙΟΤΙΚΕΣ ΚΑΙ ΠΟΣΟΤΙΚΕΣ ΣΧΕΣΕΙΣ ΜΕΤΑΞΥ ΤΟΥ ΑΙΤΙΟΥ - ΦΥΣΙΚΟΓΕΩΓΡΑΦΙΚΟΣ ΠΑΡΑΓΟΝΤΑΣ - ΚΑΙ ΤΟΥ ΑΠΟΤΕΛΕΣΜΑΤΟΣ - ΘΕΡΜΟΚΡΑΣΙΑ. ΟΙ ΦΥΣΙΚΟΓΕΩΓΡΑΦΙΚΟΙ ΠΑΡΑΓΟΝΤΕΣ, ΟΠΩΣ ΕΙΝΑΙ Η ΔΙΑΝΟΜΗ ΤΩΝ ΞΗΡΩΝ ΚΑΙ ΤΩΝ ΘΑΛΑΣΣΩΝ, ΤΟ ΥΨΟΜΕΤΡΟ, ΤΟ ΓΕΩΓΡΑΦΙΚΟΠΛΑΤΟΣ ΚΑΙ ΤΟ ΓΕΩΓΡΑΦΙΚΟ ΜΗΚΟΣ, ΑΝΑΛΥΟΝΤΑΙ ΛΕΠΤΟΜΕΡΩΣ ΜΕ ΤΗΝ ΒΟΗΘΕΙΑ ΚΛΙΜΑΤΙΚΩΝ ΜΕΘΟΔΩΝ ΑΝΑΛΥΣΗΣ ΚΑΙ ΚΑΤΑΒΑΛΛΕΤΑΙ ΠΡΟΣΠΑΘΕΙΑ ΩΣΤΕ Η ΠΑΡΟΥΣΑ ΔΙΑΤΡΙΒΗ, ΝΑ ΑΠΟΤΕΛΕΣΕΙ ΜΙΑ ΧΡΗΣΙΜΗ ΣΥΜΒΟΛΗ ΣΤΗΝ ΕΡΕΥΝΑ ΤΟΥ ΘΕΡΜΟΚΡΑΣΙΑΚΟΥ ΚΑΘΕΣΤΩΤΟΣ ΤΗΣ ΕΛΛΑΔΟΣ. ΑΠΟ ΤΟΝ ΜΕΓΑΛΟ ΑΡΙΘΜΟ ΣΥΜΠΕΡΑΣΜΑΤΩΝ ΑΝΑΦΕΡΟΥΜΕ ΧΑΡΑΚΤΗΡΙΣΤΙΚΑ ΟΤΙ Ο ΠΡΟΣΑΝΑΤΟΛΙΣΜΟΣ ΚΑΙ Η ΔΙΑΤΑΞΗ ΤΩΝ ΟΡΟΣΕΙΡΩΝ ΔΙΑΜΟΡΦΩΝΟΥΝ ΤΗΝ ΘΕΡΜΟΚΡΑΣΙΑΚΗ ΚΑΤΑΣΤΑΣΗ ΣΤΟΝ ΕΛΛΑΔΙΚΟ ΧΩΡΟ, ΟΠΩΣ ΑΥΤΟ ΠΡΟΚΥΠΤΕΙ ΑΠΟ ΤΗΝ ΔΙΑΝΟΜΗ ΤΩΝ ΙΣΟΘΕΡΜΩΝ ΚΑΘΩΣΕΠΙΣΗΣ Η ΠΟΡΕΙΑ ΤΗΣ ΚΑΤΑΚΟΡΥΦΗΣ ΘΕΡΜΟΒΑΘΜΙΔΑΣ ΕΙΝΑΙ ΑΠΛΗ ΜΕ ΜΕΓΙΣΤΑ ΚΑΤΑ ΤΟΥΣ ΧΕΙΜΕΡΙΝΟΥΣ ΜΗΝΕΣ ΚΑΙ ΕΛΑΧΙΣΤΑ ΚΑΤΑ ΤΟΥΣ ΘΕΡΙΝΟΥΣ