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In this study, we introduce an application of a Cellular Automata (CA)-based system for monitoring and estimating the spread of epidemics in real world, considering the example of a Greek city. The proposed system combines cellular structure and graph representation to approach the connections among the area's parts more realistically. The original design of the model is attributed to a classical SIR (Susceptible–Infected–Recovered) mathematical model. Aiming to upgrade the application's effectiveness, we have enriched the model with parameters that advances its functionality to become self-adjusting and more efficient of approaching real situations. Thus, disease-related parameters have been introduced, while human interventions such as vaccination have been represented in algorithmic manner. The model incorporates actual geographical data (GIS, geographic information system) to upgrade its response. A methodology that allows the representation of any area with given population distribution and geographical data in a graph associated with the corresponding CA model for epidemic simulation has been developed. To validate the efficient operation of the proposed model and methodology of data display, the city of Eleftheroupoli, in Eastern Macedonia—Thrace, Greece, was selected as a testing platform (Eleftheroupoli, Kavala). Tests have been performed at both macroscopic and microscopic levels, and the results confirmed the successful operation of the system and verified the correctness of the proposed methodology. [ABSTRACT FROM AUTHOR]

The lightning protection of photovoltaic installations is of great importance, in order to warrant the uninterrupted operation of the system and avoid faults and damages of the equipment. Atmospheric discharges influence the proper operation of the photovoltaic generators and their installation, involving also sensitive electronic equipment. The determination of the need for lightning protection and the evaluation of the performance of a risk management analysis are the first steps, in order to adopt the appropriate protective measures against lightning. Scope of the current work is to summarize the basic lightning protection techniques, taking into consideration the Standards, the international literature and the common practice. The risk management, the external and internal lightning protection system, the selection of the characteristics of the equipment and the grounding system are discussed in the current paper. [ABSTRACT FROM AUTHOR]

The increasing electrical energy price worldwide and generally the liberation of Electrical Energy Markets, has highlighted the standalone residential PV systems as a potentially viable commercial product, especially for remote areas (islands, rural territories etc). Critical values for the success of these systems are the initial required capital for such an investment, the payback period and the compatibility with national and international directives on the low voltage electrical installations and on the power quality. To this direction, an improved standalone bidirectional battery charging system for residential applications is introduced in this paper. Extended Matlab/Simulink results are validating the advantages of the proposed configuration, especially in cases of three phase short circuit faults. [ABSTRACT FROM AUTHOR]