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The geometry of wind turbine blades is characterised by the aerodynamic lift generating surface which results in lengthwise geometrical variations (LGVs), namely tapered and twisted cross sections and precurved longitudinal axis. In particular, a tapered beam presents cross-section dimensions which smoothly vary along its longitudinal span and affects the behaviour of the structure. Hence, the stress distributions in tapered structures can be at significant variance with the ones occurring in prismatic beams. The early stages of wind turbine blade design are based on simplified beam models to reduce the computational cost otherwise entailed by 3D full finite element models. The cross-section stiffness properties required for aeroelastic analysis and the prediction of the strains/stresses for structural design and optimization purposes are provided by cross-section analysis methods. Nowadays, the available cross-section analysis methods are based on prismatic hypothesis and consequently the aforementioned taper effects are ignored, notwithstanding the available scientific literature on this matter.The first part of the thesis sheds light on the effects of taper on the stresses in thinwalled isotropic beams with circular and rectangular cross sections. Elasticity theory is employed to derive closed-form analytical solutions which are compared to 3D finite element models for validation purposes. The analytical equations of the Cauchy stress components provide an insight into the role of taper in the beam behaviour. Indeed, taper evokes geometrical couplings which considerably affect the stress state of the beam. Particularly, shear-axial and shear-bending contributes to the definition of the in-plane shear component and significantly affect the in-plane shear both qualitatively and quantitatively. For instance, neglecting taper effect in structures such as wind turbine blades could result in underestimating the shear components in the proximity of the web adhesive joints, and, therefore, to detrimental designs. In addition, the provided closed-form solutions could be employed for validation of tapered cross-sectional analysis tools. In addition, the provided expressions could be used for validation of tapered cross-sectional analysis tools.The second part of the thesis investigates an alternative finite element method which suits for cross-section analysis of tapered beams. It models the beam cross-section as a tapered slice consisting of one-layered of solid finite elements. The nodal forces equivalent to axial, bending and shear are derived from the assumed surface tractionacting on the two faces of the slice. In addition, constraint equations for the six rigid body modes, namely three translations and three rotations, are enforced via the Lagrange multiplier method. Parametric studies of the relation between the stresses and the magnitude of the taper angles and the thickness of the slice are conducted on a planar isotropic wedge, whose closed-form solutions in terms of stresses are known. Results reveal the ability of the slice method to predict approximately the stresses in the tapered cross-sections of the wedge.The present study underlines the importance of the taper effects on the stress components of a tapered beam. Neglecting taper effects can result in a inaccurate stress prediction and accordingly lifetime calculation of tapered beams. The outcome of this project places the foundations for the development of a new advanced tapered cross-section analysis tool where a more accurate prediction of the stress components and lifetime of tapered structures is achieved without exploiting high computational tools.

The Italian National Strategy for Inner Areas stresses the importance of improving socio-economic conditions of people as the only way to reverse negative demographic trends in those areas. In this respect, improving quality of life (QoL) may represent a key driver. This work provides a statistical tool to measure existing gaps in QoL levels across Italian NUTS 3 regions, by focusing on inner areas. Being QoL a multidimensional concept, a composite indicator is computed following a non-compensatory approach: the QoL Mazziotta-Pareto Index. Firstly, we consider the variability of this indicator across Italy, with respect to the presence of inner areas. This analysis breaks down the supposed negative relationship between QoL and presence of inner areas, which the paper proves to be mostly overlapping with rural ones, by controlling for sub-national structural divides. Secondly, spatial aspects make the picture more complex. Neighbourhood affects QoL at local level and through global, and local indicators of spatial autocorrelation, groups of NUTS 3 regions sharing similar QoL levels with their neighbours, are detected. From a policy perspective, locked-in paths among neighbouring regions can influence the effectiveness of place-based policies., Bio-based and Applied Economics, Vol 6 No 2 (2017)

This research compares the attitudes of consumers in the United States, Italy and Japan toward food characteristics. The U.S. and Japanese consumers had relatively positive attitudes toward genetically modified food, while the Italian consumer had relatively negative attitudes. The Italian consumer was least likely to be familiar with genetically modified food. They rated organic higher than the U.S. consumer and they appeared to understand the meaning of the term organic better than the U.S. consumers. The U.S. and Japanese consumers were more concerned with freshness and value while the Italian consumers were concerned about the environment and local food.

This research uses a survey instrument in the United States and Italy to examine the relationship between consumers’ demographics, attitudes, and behaviors toward food purchasing and their self-described desire to lose weight. Approximately two-thirds of consumers in the United States and slightly over half of consumers in Italy indicated a desire to lose weight. Married consumers with children in the household in both countries are more likely to desire to lose weight. Furthermore, consumers from both countries who desire to lose weight were more likely to agree that “the main meal of the day is the most important time of the day for my household.†Although the main meal of the day is more important to consumers from both countries who desire to lose weight, consumers in the United States who desire to lose weight were more likely to indicate that every member of their families eat the main meal together. Consumers in Italy who desire to lose weight were less likely to indicate that every member of their families eat the main meal together. The self-described overweight consumers in both countries enjoy cooking and have sufficient food for their families. However, the overweight consumer in the United States is often too busy to cook. This research finds no difference in the number of meals eaten away from home in a typical week between those in each country who desire to lose weight and those who do not. Furthermore, in the United States the sources of foods eaten away from home, such as fast food, are not related to the importance to the consumer of weight loss.