University of the Aegean

About: University of the Aegean is a education organization based out in Mytilene, Greece. It is known for research contribution in the topics: Population & Tourism. The organization has 2818 authors who have published 8100 publications receiving 179275 citations. The organization is also known as: UAEG.

Patient Fall Detection using Support Vector Machines

Abstract: This paper presents a novel implementation of a patient fall detection system that may be used for patient activity recognition and emergency treatment. Sensors equipped with accelerometers are attached on the body of the patients and transmit patient movement data wirelessly to the monitoring unit. The methodology of support Vector Machines is used for precise classification of the acquired data and determination of a fall emergency event. Then a context-aware server transmits video from patient site properly coded according to both patient and network status. Evaluation results indicate the high accuracy of the classification method and the effectiveness of the proposed implementation.

Evaluation of a three-dimensional chemical transport model (PMCAMx) in the European domain during the EUCAARI May 2008 campaign

Abstract: PMCAMx-2008, a detailed three dimensional chemical transport model (CTM), was applied to Europe to simulate the mass concentration and chemical composition of particulate matter (PM) during May 2008 The model includes a state-of-the-art organic aerosol module which is based on the volatility basis set framework treating both primary and secondary organic components to be semivolatile and photochemically reactive The model performance is evaluated against high time resolution aerosol mass spectrometer (AMS) ground and airborne measurements Overall, organic aerosol is predicted to account for 32% of total PM1 at ground level during May 2008, followed by sulfate (30%), crustal material and sea-salt (14%), ammonium (13%), nitrate (7%), and elemental carbon (4%) The model predicts that fresh primary OA (POA) is a small contributor to organic PM concentrations in Europe during late spring, and that oxygenated species (oxidized primary and biogenic secondary) dominate the ambient OA The Mediterranean region is the only area in Europe where sulfate concentrations are predicted to be much higher than the OA, while organic matter is predicted to be the dominant PM1 species in Central and Northern Europe The comparison of the model predictions with the ground measurements in four measurement stations is encouraging The model reproduces more than 94% of the daily averaged data and more than 87% of the hourly data within a factor of 2 for PM1 OA The model tends to predict relatively flat diurnal profiles for PM1 OA in many areas, both rural and urban, in agreement with the available measurements The model performance against the high time resolution airborne measurements at multiple altitudes and locations is as good as its performance against the ground level hourly measurements There is no evidence of missing sources of OA aloft over Europe during this period © Author(s) 2011

An integrated approach to watershed management within the DPSIR framework: Axios River catchment and Thermaikos Gulf

Abstract: The coastal zone of the inner Thermaikos Gulf has been influenced by eutrophication during the past decades. The conditions of the catchment area-coastal zone continuum are assessed under the holistic Driver-Pressure-State-Impact-Response (DPSIR) framework. Major socioeconomic drivers, such as industrial and agricultural development as well as urbanization, exert substantial environmental pressures on the Axios River and the Thermaikos Gulf. The Thermaikos Gulf is a highly complex system, being affected by nutrient inputs from four rivers and the City of Thessaloniki. Moreover, the Axios River which is the most significant contributor of freshwater and nutrients to the gulf, is a transboundary river shared between Greece and the Former Yugoslav Republic of Macedonia (FYROM). The two countries have not yet established a mutual management plan to control freshwater and nutrient discharges. Long-term analysis has shown that presently, more than 11,800 t of nitrogen and 3,400 t of phosphorous are released annually into the marine system. In the Antropocene era, and particularly during the past 20 years, freshwater discharges have decreased and riverine nutrients have increased, whereas inputs from domestic and industrial effluents have a decreasing trend. However, nutrient over-enrichment impacts, i.e. eutrophication, harmful algal blooms and hypoxia still have to be addressed in order to identify whether the coastal system is recovering, or whether further actions should be undertaken to control nutrient inputs from the Axios River and/or other sources. Response actions, such as the improvement of Thessaloniki’s wastewater treatment plant, have proved to play a positive role in the reduction of domestic wastewater input in the gulf, whereas similar facilities are completely lacking in FYROM. On the other hand, several parts of the Axios River delta are designated as protected areas, in an effort to protect environmentally rich habitats. These efforts are often disputed by local stakeholders, which have conflicting interests in the use of the hinterland and the coastal environment. The need of an integrated catchment-coastal zone management plan appears as a fundamental priority in order to protect, improve and maintain the environment, taking into account the need for economic development of the area. The DPSIR conceptual framework appears to be a valuable tool, as it enables parallel assessment of socioeconomic and environmental issues. In combination with the application of numerical models, the DPSIR analysis may provide suggestions for sustainable and environmentally-friendly measures to policy makers.

An integrated computer supported acquisition, handling, and characterization system for pigmented skin lesions in dermatological images

Abstract: This paper describes an integrated prototype computer-based system for the characterization of skin digital images. The first stage includes an image acquisition arrangement designed for capturing skin images, under reproducible conditions. The system processes the captured images and performs unsupervised image segmentation and image registration utilizing an efficient algorithm based on the log-polar transform of the images' Fourier spectrum. Border- and color-based features, extracted from the digital images of skin lesions, were used to construct a classification module for the recognition of malignant melanoma versus dysplastic nevus. Different methods, drawn from the fields of artificial intelligence (neural networks) and statistical modeling (discriminant analysis), were used in order to find the best classification rules and to compare the results of different approaches to the problem.