Point to point multispectral light projection applied to cultural heritage

Use of new of light sources based on LED technology should allow the develop of systems that combine conservation and exhibition requirements and allow to make these art goods available to the next generations according to sustainability principles. The goal of this work is to develop light systems and sources with an optimized spectral distribution for each specific point of the art piece. This optimization process implies to maximize the color fidelity reproduction and the same time to minimize the photochemical damage. Perceived color under these sources will be similar (metameric) to technical requirements given by the restoration team uncharged of the conservation and exhibition of the goods of art. Depending of the fragility of the exposed art objects (i.e. spectral responsivity of the material) the irradiance must be kept under a critical level. Therefore, it is necessary to develop a mathematical model that simulates with enough accuracy both the visual effect of the illumination and the photochemical impact of the radiation. Spectral reflectance of a reference painting The mathematical model is based on a merit function that optimized the individual intensity of the LED-light sources taking into account the damage function of the material and color space coordinates. Moreover the algorithm used weights for damage and color fidelity in order to adapt the model to a specific museal application. In this work we show a sample of this technology applied to a picture of Sorolla (1863-1923) an important Spanish painter title “woman walking at the beach”

The fate of mercury in an activated sludge pilot plant

The objectives of this thesis were the study of the mercury contaminated wastewater input effects at the activated sludge pilot plant and the examination of merkury's fate during the activated sludge process. In this thesis 17 of the most important physical, chemical and biological parameters of the pilot plant were measured during the seven (7) series of experiments. The main conclusions of this thesis are: the introduction of wastewater which was contaminated with Mercury (10-600 μg/L), into the plant affect statistically significant: a) The total bacterial number in the aeration tank, b) the growth rate of several bacterial species in the aeration tank, c) the size distribution of the suspended solids in the aeration tank and at the outlet of the plant and d) the organic loading removal ability of the plant. The most important specie of the mercury during the activated sludge process was the particulate mercury. There was not detected methylation of the incoming inorganic mercury during the activated sludge process. The mercury removal ability of the plant was 61,06% and the parameters which affect the removal ability of mercury were: the temperature, the incoming concentration of the metal and the acclimatization of the aeration tank bacteria to merccury existence. The incoming concentrations of mercury during the 7 series of exoeriments were 10-600 μg Hg/L.Στόχος της διατριβής ήταν η διερεύνηση των επιπτώσεων της εισροής υδραργύρου στην λειτουργία μιας πιλοτικής μονάδας ενεργού ιλύος καθώς και η έρευνα της τύχης του μετάλλου. Έγινε προσδιορισμός δεκα έξι (16) φυσικών, χημικών και βιολογικών παραμέτρων κατά την διάρκεια επτά (7) σειρών πειραμάτων. Τα κύρια συμπεράσματα της συγκεκριμένης διατριβής ήταν: η εισροή υδραργύρου στην πιλοτική μονάδα, επηρέασε στατιστικά σημαντικά: τον αριθμό των βακτηρίων και την κατανομή μεγέθους των αιωρούμενων στερεών δεξαμενή αερισμού καθώς και την ικανότητα απομάκρυνσης του οργανικού φορτίου της μονάδας. Η κυρίαρχη μορφή του υδράργυρου κατά την διάρκεια της επεξεργασίας των υγρών αποβλήτων ήταν ο σωματιδιακός ενώ δεν ανιχνεύτηκε μεθυλίωση του εισερχόμενου ανόργανου υδράργυρου. Η ικανότητα απομάκρυνσης του υδράργυρου ήταν κατά μέσον όρο 61,06 % και παράγοντες που την επηρεάζουν είναι η θερμοκρασία, η συγκέντρωση εισόδου του μετάλλου και ο εγκλιματισμός της βιοκοινωνίαςτης δεξαμενής αερισμού της μονάδας στην ύπαρξή του. Οι συγκεντρώσεις εισροής του υδραργύρου κατα την διάρκεια όλων των πειραμάτων κυμάνθηκαν απο 10-600 μg Hg/L

Coastline Zones Identification and 3D Coastal Mapping Using UAV Spatial Data

WOS: 000379861200002Spatial data acquisition is a critical process for the identification of the coastline and coastal zones for scientists involved in the study of coastal morphology. The availability of very high-resolution digital surface models (DSMs) and orthophoto maps is of increasing interest to all scientists, especially those monitoring small variations in the earth's surface, such as coastline morphology. In this article, we present a methodology to acquire and process high resolution data for coastal zones acquired by a vertical take off and landing (VTOL) unmanned aerial vehicle (UAV) attached to a small commercial camera. The proposed methodology integrated computer vision algorithms for 3D representation with image processing techniques for analysis. The computer vision algorithms used the structure from motion (SfM) approach while the image processing techniques used the geographic object-based image analysis (GEOBIA) with fuzzy classification. The SfM pipeline was used to construct the DSMs and orthophotos with a measurement precision in the order of centimeters. Consequently, GEOBIA was used to create objects by grouping pixels that had the same spectral characteristics together and extracting statistical features from them. The objects produced were classified by fuzzy classification using the statistical features as input. The classification output classes included beach composition (sand, rubble, and rocks) and sub-surface classes (seagrass, sand, algae, and rocks). The methodology was applied to two case studies of coastal areas with different compositions: a sandy beach with a large face and a rubble beach with a small face. Both are threatened by beach erosion and have been degraded by the action of sea storms. Results show that the coastline, which is the low limit of the swash zone, was detected successfully by both the 3D representations and the image classifications. Furthermore, several traces representing previous sea states were successfully recognized in the case of the sandy beach, while the erosion and beach crests were detected in the case of the rubble beach. The achieved level of detail of the 3D representations revealed new beach characteristics, including erosion crests, berm zones, and sand dunes. In conclusion, the UAV SfM workflow provides information in a spatial resolution that permits the study of coastal changes with confidence and provides accurate 3D visualizations of the beach zones, even for areas with complex topography. The overall results show that the presented methodology is a robust tool for the classification, 3D visualization, and mapping of coastal morphology.European Regional Development Fund (ERDF)European Union (EU); national fund of Greece under the Cross-Border Cooperation Programme Greece-Cyprus; national fund of Cyprus under the Cross-Border Cooperation Programme Greece-CyprusThis work is supported by the Action entitled: "Cross-Border Cooperation for the development of Marine Spatial Planning" referred as THAL-CHOR is co-funded by the European Regional Development Fund (ERDF) by 80% and by national funds of Greece and Cyprus by 20%, under the Cross-Border Cooperation Programme Greece-Cyprus 2007-2013

The Sound of Drystones: A Novel Hot-Spot of Ecoacoustics Research

Drystone terraces offer a series of ecosystem services including both biological and cultural benefits. The aesthetic contribution towards the landscape and the increase in biodiversity levels, constitute drystone terraces and other similar constructions, as important biocultural assets. The low maintenance and the eventual abandonment of drystone terraces cause a series of drawbacks regarding the sustainability of agricultural environments. The main goal of this research was to assess the effect of drystone terrace maintenance level on biodiversity. For that reason, two closely distant agricultural areas of Lesbos Island (North Aegean, Greece) in which olive grove drystone terraces dominate were compared. The non-intrusive method of ecoacoustics was selected, and the levels of the acoustic complexity and acoustic diversity were statistically analyzed for areas that included highly maintained and poorly maintained olive grove drystone terraces. The results indicated an increase in acoustic biodiversity levels in the poorly maintained drystone terraces area. At this early stage, the results highlighted the fact that the increased resources in the poorly maintained drystone terraces, in terms of nesting and feeding opportunities, increased the biodiversity levels. Nevertheless, the spatiotemporal expansion of this research is undeniably important

The Sound of Drystones: A Novel Hot-Spot of Ecoacoustics Research

Drystone terraces offer a series of ecosystem services including both biological and cultural benefits. The aesthetic contribution towards the landscape and the increase in biodiversity levels, constitute drystone terraces and other similar constructions, as important biocultural assets. The low maintenance and the eventual abandonment of drystone terraces cause a series of drawbacks regarding the sustainability of agricultural environments. The main goal of this research was to assess the effect of drystone terrace maintenance level on biodiversity. For that reason, two closely distant agricultural areas of Lesbos Island (North Aegean, Greece) in which olive grove drystone terraces dominate were compared. The non-intrusive method of ecoacoustics was selected, and the levels of the acoustic complexity and acoustic diversity were statistically analyzed for areas that included highly maintained and poorly maintained olive grove drystone terraces. The results indicated an increase in acoustic biodiversity levels in the poorly maintained drystone terraces area. At this early stage, the results highlighted the fact that the increased resources in the poorly maintained drystone terraces, in terms of nesting and feeding opportunities, increased the biodiversity levels. Nevertheless, the spatiotemporal expansion of this research is undeniably important

A GIS-based decision support model for offshore floating wind turbine installation

This paper presents a decision support model that assesses offshore suitability for floating wind turbine installation. The model is based on Multi-Criteria Analysis and Geographic Information Systems. An implementation of the model for the Aegean Sea is also presented. The methodological approach followed consists of four stages. The first stage excludes sites that are inappropriate for wind turbine siting based on legislative constraints. At the second stage, a set of evaluation criteria are used in order to identify the most suitable areas for floating wind turbine installation. Next stage is the economic evaluation of the highest-scored sites, as they resulted from final suitability map. Finally, a sensitivity analysis on the weights of the criteria is carried out. Results indicated that only a small percentage of the case study is characterised as appropriate for floating wind turbine siting, although wind potential is considered strong in more sites