In the present study, a recently developed novel approach (Bender et al. in J Hydrol 514:123-130, 2014) has been further extended to investigate the changes in the joint probabilities of extreme offshore and nearshore marine variables with time and to assess design the total water level (TWL) at the shoreline under the effects of climate change. The nonstationary generalised extreme value (GEV) distribution has been utilised to model the marginal distribution functions of marine variables (wave characteristics and sea levels), within a 40-year moving window. All parameters of the GEV were tested for statistically significant linear and polynomial trends over time, and best-fitted trends have been detected. Different copula functions were fitted at the 40-year moving windows, to model the dependence structure of extreme offshore significant wave heights and peak spectral periods, and of wave-induced sea levels on the shoreline and nearshore sea levels due to storm surges. The most appropriate bivariate models were then selected. Statistically significant polynomial trends were detected in the dependence parameters of the selected copulas, and time-dependent most likely bivariate events were extracted to be used in the estimation of the TWL at the shoreline. The methods of the present work were implemented in three selected Greek coastal areas in the Aegean Sea. The analysis revealed different variations in the most likely estimates of the offshore wave characteristics and nearshore storm surges in the three study areas, as well as in the time-dependent estimates of TWL at the shoreline. The approach combines nonstationarity and bivariate analysis, blends coastal and offshore marine features and finally provides non-trivial alterations in the response of coastal sea level dynamics to climate change signals, compared to former work on the subject. The methodology produces reasonable estimates of design quantities for coastal structures and boundary conditions for the assessment of flood hazard and risk in coastal areas.

In this work, the fabrication and characterization of flexible organic light emitting diode (OLED) devices by printing processes is presented. New synthesized anthracene-based polymer as well as commercially available polymers such as polyfluorenes and polyphenylene vinylenes were applied as emitting materials. The photoluminescence (PL) properties of the polymer films were evaluated revealing the characteristic emission of each material. The optical properties of the polymers were investigated by NIR-Vis-far UV spectroscopic ellipsometry. The accurate determination of the thickness and the optical properties were derived. Furthermore, electrooptical characteristics brightness, chromaticity, and current density-voltage characteristics of the devices were obtained. Correlations between the optical properties, PL characteristics, and device performances were established. This provides substantial insights into the final design of the optimum final multi-layer structure of the OLEDs whereas the potentiality for the development of flexible OLEDs with bigger active area devices by printing processes is demonstrated.

White Organic Light‐Emitting Diodes (WOLEDs) have attracted an enormous interest because they can be implemented in numerous lighting applications as next‐generation light sources. Several device setups such as multilayer, blends, or single layers of polymer nanomaterials have been proposed to achieve white light emission. In this work, novel copolymers bearing blue, yellow, and red chromophores, are used for the fabrication of WOLED systems including single emissive layer. These terpolymers provide easy tuning of white color emission by selecting the appropriate ratios between the chromophores while being solution processable from typical organic solvents, like chlorobenzene (CB), o‐dichlorobenzene (o‐DCB), etc. The chromophores can be directly excited by capturing charge carriers or through energy transfer from the other chromophores. Incomplete energy transfer between the chromophores is necessary to get white light as combined emission from all of them. The opto‐electronic and electro‐optical characterization is carried out by NIR–Vis–far UV spectroscopic ellipsometry, photoluminescence, and electroluminescence, to provide valuable information toward the optimization and functionalization of these WOLED devices.

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