Validation of Voltage Instability Detection and Control Using a Real Power System Incident

This paper applies a voltage instability monitoring method based on voltage and current measurements from a transmission bus PMU on the Hellenic Interconnected System using both unstable and marginally stable scenarios, derived from the historical 12 July 2004 blackout of the Athens area. The effectiveness, selectivity and reliability of the proposed monitoring method is clearly demonstrated, allowing its integration into a System Protection Scheme with direct load shedding. It is shown that the proposed instability detection and control scheme could have prevented the voltage collapse if applied at the time of the event.

Conceptualizing Motives for Migration: a Typology of Italian Migrants in the Athens Area

Migration flows from a southern European country to another one have received scarce attention so far. This is especially true for Italians migrating to Greece or, more specifically, the Athens area. Thus, there are limited insights as to the reasons why Italians are leaving and why they have been choosing Greece as their destination. This paper looks at their motives for migrating and their destination choice in order to understand the diversity of migratory trajectories through a typology. In order to do this, we carried out in-depth interviews to Italians living, both permanently and temporarily, in the Athens area, employing snowball sampling. As a result, we have identified 5 types of Italian immigrants in Athens: Mediterranean, nomadic, work, entrepreneurial, and marriage migrants. Mediterranean migrants are driven by the typically Mediterranean character of climate, landscape, food, and culture in their deliberate choice of Athens. Nomadic migrants have casually chosen Athens to satisfy their need of continuous physical mobility and multiple moorings as a defining aspect of their identity. Work migrants are motivated by the search of a job regardless of the place and work content. Entrepreneurial migrants are motivated by a vocation for a professional career in Athens. Finally, for marriage migrants, the choice of Athens is a consequence of a couple choice and shared life projects.

A hybrid dynamical-statistical downscaling approach for climate change impacts analysis on high resolution in the Greater Athens Area

<p>The available state-of-the art Regional Climate Model (RCM) simulations from the Euro-Cordex initiative have an horizontal resolution of about 12km which although is adequate for assessing regional climate change impacts is still coarse for studying the climate change impacts in an urban environment such as the Greater Athens Area (GAA). To this aim we propose a hybrid dynamical-statistical downscaling approach that produces high resolution, in the order of 1km, climate change projections for two future periods and under two RCP scenarios. To produce the higher resolution climate projections we combine the results of the Weather Research and Forecasting model (WRF) - Version 3.9.1 -including a single-layer urban canopy model to represent the urban tile- with available RCMs simulations obtained from the Euro-Cordex database.</p><p>Initially an annual WRF, ERA interim driven, simulation for a year identified as a “representative year” for the period 1971-2000 in the GAA is performed at an horizontal resolution of 1km. Subsequently the spatial signal of the WRF simulation is passed to the ERA interim driven RCM simulations for the period 1971-2000 using the unbiasing bias adjusting method which maintains the absolute trend as well as the variability of the RCM simulated data at all time scales. In a second step the donwscaled RCM evaluation simulations are used to bias adjust the transient RCM simulations using the empirical quantile method (EQM). EQM works by matching the transient simulations empirical cumulative distributions to the evaluation ones. This is achieved by establishing a quantile-dependent correction function between them during the reference period. The correction functions are then applied to both the historical and the future periods.</p><p>In this study we present the results for temperature and precipitation but the methodology can be extended to other variables of interest assuming that the WRF and the evaluation RCM simulations adequately reproduce their spatial and temporal variability, respectively.</p>

Event Co-Creation in Street Events. Evidence from Athens Pride

espite the significant contribution of events in tourism and development of urban areas, the cocreation aspects of street events appear to be under searched in the literature. Athens Pride is one of the largest street events in Athens and it aims to promote and support lesbian, gay, bisexual, transgender, and queer issues (LGBT+) in the greater Athens area, Greece. Using a sample of 312 Athens Pride adult attendees and employing linear analysis, this study focuses on the aspects that form this street event’s co-creation. The findings reveal that participation incentives and emotional closeness are the main factors in order to formulate and strengthen event co-creation, followed by the community commitment and the brand image of the event. In addition, the study showcases the importance of three socio-demographics (age; level of education; sexual orientation) upon event co-creation. The research also provides managerial suggestions for event organisers in order to further strengthen street event co-creation and the experience of their attendees.

Gambling in adolescents during the financial crisis in Greece

Problem gambling emerges as a serious and ever growing problem of modern societies, largely affecting adolescents as well. The etiology of gambling disorder is complex and multifaceted as it is governed by multiple and interrelated factors. In this context and in light of the pervasive financial crisis in Greece, we conducted a study in order to explore adolescents’ gambling involvement in Athens region and also to identify the socio-economic characteristics of adolescents who have engaged into gambling activities. Students were recruited from a sample of schools in Athens area. For the assessment of gambling involvement in adolescents, the Diagnostic and Statistical Manual of Mental Disorders-IV Multiple Response Adapted for Juveniles Questionnaire (DSM-IV-MR-J) was administered. Additional self-constructed questions enquired about students’ socio-demographic and economic characteristics. Our results indicate that adolescents that had problem with gambling or had at least one pathological item on DSM were more likely to be boys and to have been born in a country other than Greece. Additionally, the proportion of those having at least one pathological item on DSM was greater in those with low school grades. Τhe lack of food in the household due to inability of providing food during the last month was significantly associated with both having problem with gambling and having at least one pathological item on DSM. Furthermore, having been worried that there would not be enough food during the last month and having been fed with a restrained variety of food due to lack of recourses were associated with at least one pathological item on DSM. These findings are congruent with the literature suggesting that youth living under poverty often resort to gambling. In conclusion, our results point out the adverse effects of the financial crisis on the development of problem gambling in adolescents within the Greek society. Problem gambling may have developed in response to the ubiquitous insecurity characterizing the Greek society during this rough time period. Interventions should prioritize endowing adolescents with the necessary coping skills for dealing with daily obstacles or life adversities productively and without losing their self-control.

Spatial Characteristics of PM1 Aerosol Chemical Composition over the Greater Athens Area

Airborne sub-micrometer particles (PM1) have been documented to exert adverse impacts on human health, including respiratory and cardiovascular disease and premature mortality. The Greater Athens Area (GAA), characterized by topographic and meteorological conditions which frequently obstruct the effective dispersion of ambient pollutants, hosts approximately 40% of Greece’s population. It can be considered an “ambient laboratory” for studying PM1 pollution events, given the intensity and diversity of submicron aerosol sources and processing. Fine aerosol chemical composition is continuously monitored at the National Observatory of Athens Air Monitoring Station in Thissio, an urban background site in Central Athens. Furthermore, two intensive monthly campaigns were held at a central site in Piraeus, where Greece’s busiest passenger port is located, during both winter (December 2018–January 2019) and summer (June–July 2019) periods. Organic aerosol (OA), sulfate, nitrate, ammonium, and chloride were measured using an aerosol chemical speciation monitor (ACSM), while black carbon (BC and source-specific components) was measured using a multi-wavelength aethalometer (AE-33). The variability of concentrations at different temporal scales was examined, revealing differences for primary aerosol components, depending on site type and location, and related to local sources and transport processes. Biomass burning for domestic heating was found to be a key factor during wintertime, leading to uniform OA and BC levels at both sites, while the local sources in Piraeus (traffic, port activity) lead to substantially increased levels during the summer. Secondary sources were found to affect both sites in a relatively homogeneous manner.

Differentiation of the Athens Fine PM Profile during Economic Recession (March of 2008 Versus March of 2013): Impact of Changes in Anthropogenic Emissions and the Associated Health Effect

Despite the various reduction policies that have been implemented across Europe in the past few years, Particulate Matter (PM) exceedances continue to be recorded. Therefore, with the principal aim to clarify the complex association between emissions and fine particles levels, this work evaluates the impact of the anthropogenic contribution to the fine PM chemical profile. The fieldwork was conducted during March in 2008 and 2013 and covers the periods before and during the economic recession. The experimental data were analyzed in parallel with the emissions from the Flexible Emission Inventory for Greece and the Greater Athens Area (FEI-GREGAA). The differentiation of the mass closure results’ and the aerosols’ character is also discussed in combination with the calculated PM2.5-Air Quality Indexes. The peak in the PM load and the Particulate Organic Matter (POM) component was recorded in 2013, corresponding to the enhancement of the anthropogenic input. Although the monitoring location is traffic-impacted, the sector of heating, from both wood burning and fossil fuel, proved to be the driving force for the configuration of the obtained PM picture. Especially in 2013, its contribution was two times that of traffic. Finally, the low wind speed values led to the deterioration of the air quality, especially for the sensitive groups.

Spatiotemporal Evaluation of PM10 Concentrations within the Greater Athens Area, Greece. Trends, Variability and Analysis of a 19 Years Data Series

This work investigates the spatiotemporal variation of suspended particles with aerodynamic diameter less than or equal to 10 μm (PM10) during a nineteen years period. Mean daily PM10 concentrations between 2001 and 2018, from five monitoring stations within the greater Athens area (GAA) are used. The aim is to investigate the impact of the economic crisis and the actions taken by the Greek state over the past decade on the distribution of PM10 within the GAA. Seasonality, intraweek, intraday and spatial variations of the PM10 concentrations as well as trends of data, are statistically studied. The work may assist the formation of PM10 forecasting models of hourly, daily, weekly, monthly and annual horizon. Innovations are alternative ways of statistical treatment and the extended period of data, which, importantly, includes major economic and social events for the GAA. Significant decreasing trend in PM10 series concentrations at all examined stations were found. This may be due to economic and social reasons but also due to measures taken by the state so as to be harmonised with the European Directives concerning the protection of public health and the atmospheric environment of the European Union (EU) members.