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At least 1,621 records · Page 90

Road-corridor planning in the EIA procedure in Spain. A review of case studies

The assessment of different alternatives in road-corridor planning must be based on a number of well-defined territorial variables that serve as decision making criteria, and this requires a high-quality preliminary environmental assessment study. In Spain the formal specifications for the technical requirements stipulate the constraints that must be considered in the early stages of defining road corridors, but not how they should be analyzed and ranked. As part of the feasibility study of a new road definition, the most common methodology is to establish different levels of Territorial Carrying Capacity (TCC) in the study area in order to summarize the territorial variables on thematic maps and to ease the tracing process of road-corridor layout alternatives. This paper explores the variables used in 22 road-construction projects conducted by the Ministry of Public Works that were subject to the Spanish EIA regulation and published between 2006 and 2008. The aim was to evaluate the quality of the methods applied and the homogeneity and suitability of the variables used for defining the TCC. The variables were clustered into physical, environmental, land-use and cultural constraints for the purpose of comparing the TCC values assigned in the studies reviewed. We found the average quality of the studies to be generally acceptable in terms of the justification of the methodology, the weighting and classification of the variables, and the creation of a synthesis map. Nevertheless, the methods for assessing the TCC are not sufficiently standardized; there is a lack of uniformity in the cartographic information sources and methodologies for the TCC valuation. -- Highlights: • We explore 22 road-corridor planning studies subjected to the Spanish EIA regulation. • We analyze the variables selected for defining territorial carrying capacity. • The quality of the studies is acceptable (methodology, variable weighting, mapping). • There is heterogeneity in the methods for territorial carrying capacity valuation.

54 ENVIRONMENTAL SCIENCES↗

Finite element procedure for thermomechanical and structural integrity analysis of beam intercepting devices subjected to free electron laser

High-energy particles, including photons (x-ray, γ-ray, bremsstrahlung), electrons, and protons, possess the capability to penetrate materials and deposit energy within them. The degree of absorption depends on both the energy and type of particles, as well as the properties of the materials with which they interact. This energy deposition can manifest either at the material's surface or throughout its volume, potentially resulting in various failure modes. The primary aim of this paper is to establish a structured analysis methodology for evaluating the structural integrity of beam-intercepting devices when subjected to high-energy particles. Here, the paper also reviews some of the underlying physics, pertinent to the scope of the thermomechanical analysis, potential failure modes, and introduces verification and validation methodologies. Engineers and researchers can utilize the guidelines presented in this paper to effectively plan the development of beam intercepting devices, thereby ensuring their reliability and performance in the presence of high-energy particle exposure.

Finite element analysis↗