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MusTT sustainability framework: SII en SIA methods and user guide : final deliverable 4 for the DG-ENTR MusTT project

Structural design and material comparison for aircraft wing box beam panel

This paper aims to present a comprehensive investigation to obtain the structural calculations needed to design a rigid panel of aluminum alloy for the wing box beam of an ATR 72–500 aircraft. For this design process, several types of materials, including composites like CFRP, are considered so it is possible to compare the actual existing part made of aluminum to them, thus checking the advantages these new materials offer. The research presents an introduction to structural design and provides a study of the relevant literature. The aircraft's principal characteristics and performance abilities were collected so that structural loads can be computed. Research used several methods, a design using conventional methods, applying the theory of elasticity is performed using the Theory of Farrar, allowing us to obtain an analytical solution to the problem, followed by checking the obtained results using Ansys FEM software combined with the parts being designed with CATIA. Furthermore, this same panel is calculated using composite materials instead of conventional aluminum, allowing us to compare both solutions. This research shed light on the intricate process of aircraft structural design, materials selection, and calculation methodologies, highlighting the ongoing pursuit of new and advanced materials. This paper makes clear that using composite materials presents several advantages over traditional ones, allowing for lighter, safer, more fuel-efficient, and more sustainable aircraft. The use of composite materials in the construction of airplane structures is driven by many factors. The results show that the chosen composite materials reduce weight, are durable, have low maintenance requirements, reduce noise, enhance fuel economy, and are resistant to corrosion.

Usefulness of non-linear input-output models for economic impact analyses in tourism and recreation

In tourism and recreation management it is still common practice to apply traditional input-output (IO) economic impact models, despite their well-known limitations. In this study the authors analyse the usefulness of applying a non-linear input-output (NLIO) model, in which price-induced input substitution is accounted for. For large changes in final demand, a NLIO model is more useful than a traditional IO model, leading to higher or lower impacts. For small changes in final demand input substitution is less likely. In that case the application of the NLIO may lead to the same results as a traditional IO model. To analyse changes of subsidies, a traditional IO model is not an option. A more flexible model, such as the NLIO, is required. The NLIO model forces researchers to make choices about capacity constraints, factor mobility and the substitution elasticity, which can be difficult but create flexibility and allow for more realism.

Usefulness of non-linear input-output models for economic impact analyses in tourism and recreation

In tourism and recreation management it is still common practice to apply traditional input-output (IO) economic impact models, despite their well-known limitations. In this study the authors analyse the usefulness of applying a non-linear input-output (NLIO) model, in which price-induced input substitution is accounted for. For large changes in final demand, a NLIO model is more useful than a traditional IO model, leading to higher or lower impacts. For small changes in final demand input substitution is less likely. In that case the application of the NLIO may lead to the same results as a traditional IO model. To analyse changes of subsidies, a traditional IO model is not an option. A more flexible model, such as the NLIO, is required. The NLIO model forces researchers to make choices about capacity constraints, factor mobility and the substitution elasticity, which can be difficult but create flexibility and allow for more realism.

An economic perspective on the legalisation debate: the Dutch case

This paper reviews how economic modelling provides a deeper understanding of drug markets. The exercise focuses on ‘soft drugs’ (cannabinoids) in the Netherlands and outlines the effects of prohibition and legalisation. The purpose is to present an overview of analytical tools to non-economists. Based on a basic supply and demand framework the impact of enforcement, externalities, producer incentives and demand elasticity are highlighted. Results indicate that social welfare is maximized under legalisation given limited externalities associated with consumption and price inelastic demand. We recommend a liberalized soft drugs market that requires inter alia taxation, complemented with various health measures like quality controls and public campaigns. The Dutch case is exemplary, as this economic perspective offers universal building blocks relevant to the legalisation debate in other countries, and potentially to other substances

On the cost elasticity of inter-regional distribution structures: a case study for the Netherlands

Several studies show that logistics facilities have spread spatially from relatively concentrated clusters in the 1970s to geographically more decentralized patterns away from urban areas. The literature indicates that logistics costs are one of the major influences on changes in distribution structures, or locations and usage of logistics facilities. Quantitative modelling studies that aim to describe or predict these phenomena in relation to logistics costs are lacking, however. This is relevant to design more effective policies concerning spatial development, transport and infrastructure investments as well as for understanding environmental consequences of freight transport. The objective of this paper is to gain an understanding of the responsiveness of spatial logistics patterns to changes in these costs, using a quantitative model that links production and consumption points via distribution centers. The model is estimated to reproduce observed use of logistics facilities as well as related transport flows, for the case of the Netherlands. We apply the model to estimate the impacts of a number of scenarios on the spatial spreading of regional distribution activity, interregional vehicle movements and commodity flows. We estimate new cost elasticities, of the demand for trade and transport together, as well as specifically for the demand for the distribution facility services. The relatively low cost elasticity of transport services and high cost elasticity for the distribution services provide new insights for policy makers, relevant to understand the possible impacts of their policies on land use and freight flows.