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Risk analysis has become a priority for authorities and stakeholders in many European countries, with the aim of reducing flooding risk by considering the priority and benefits of possible interventions. Within this context, a flood risk analysis model was developed in this study that is based on GIS, and integrated with a model that assesses the degree of accessibility and operability of strategic emergency response structures in an urban area. The proposed model is unique in that it provides a quantitative estimation of flood risk on the basis of the operability of the strategic emergency structures in an urban area, their accessibility, and connection within the urban system of a city (i.e., connection between aid centres and buildings at risk) in the emergency phase. The results of a case study in the Puglia Region in Southern Italy are described to illustrate the practical applications of this newly proposed approach. The main advantage of the proposed approach is that it allows for the defining of a hierarchy between different infrastructures in the urban area through the identification of particular components whose operation and efficiency are critical for emergency management. This information can be used by decision makers to prioritize risk reduction interventions in flood emergencies in urban areas.

We consider electron transport in a Datta–Das spin transistor within the two-subband model taking into account intra- and inter-subband spin–orbit (SO) interactions, and study the influence of inter-subband SO coupling on the spin transistor operation. Starting from the model in which the SO coupling constants are treated as parameters, we show that the inter-subband SO interaction strongly affects the ordinary conductance oscillations predicted for the transistor with single occupancy. Interestingly, we find that even in the absence of the intra-subband SO interaction, the conductance oscillates as a function of the inter-subband SO coupling constant. This phenomenon is explained as resulting from the inter-subband transition with spin flip. Next, we consider the realistic spin transistor model based on the gated AlInAs/GaInAs double quantum well, for which the SO coupling constants are determined by the Schrodinger–Poisson approach. We show that the SO coupling constants rapidly change around V g = 0, which is desirable for spin transistor operation. We demonstrate that for high electron densities the inter-subband SO interaction starts to play the dominant role. The strong evidence of this interaction is the reduction of the conductance for gate voltage V g = 0, which leads to the reduction of the on/off conductance ratio.

It is an established fact that property owners can face significant liabilities as a result of an on-site environmental contamination problem. This paper outlines a successful, innovative remedial strategy that, in conjunction with agency negotiation, afforded a property owner minimal financial expenditure and, at the same time, facilitated property cleanup and reuse. The strategy includes the delisting and sale of “clean” portions of the property to obtain the finances necessary to remediate the remaining “impacted” portion of the property. Previous investigations performed by EPA indicate the affected area to be a five to seven acre area located in the northeast portion of the property. Since a portion of the property was affected, significant restrictions for long-term use were placed on the entire property. A summary of environmental data generated for the property was prepared and submitted to the agency. This data summary communicated a strategy which was developed to delist and sell the “clean” portion of the property and to use the proceeds to clean up the affected property. To accomplish this, several tasks were outlined, including work-plan preparation and submittal, data collection, and interim remedial activities. In addition, a risk assessment is planned to identify potential threats to receptors downgradient of the impacted areas. This strategy allows the owner of an environmentally distressed property to use financial assets of the property to facilitate an acceptable solution with both regulatory agencies and the surrounding community.

Stability of (Mg-Al) clusters in the ?-Mg2Al3 structure has been studied with the use of the effective pair potential of interatomic interactions taken from ab-initio calculations. The total potential energy has been calculated for various possible (Mg-Al) cluster configurations in order to find the optimal ones. The computation has been started from the cluster located at the 8(b) site consisting of 72 partially occupied, overlapping atomic sites, as determined by X-ray studies. The configurations of fully occupied, non-overlaping atomic positions have been selected using the criterion of minimal potential energy. The simulated annealing algorithm has been used for further optimization of the atomic positions in 3D space. The energy optimization leads to the selection of several configurations with the energy close to the minimum. For such structures the configuration entropy has been calculated as a function of the total potential energy. More complex structures, consisting of the optimized clusters and various interface configurations, have been also studied.