An Interdependent Multi-Layer Model: Resilience of International Networks

Trade flows are characterised by interdependent economic networks such as the global supply chain, international bilateral agreements, trans-national credit, and foreign direct investments, as well as non-economic components (i.e. infrastructures, cultural ties and spatial barriers). We construct an Interdependent Multi-layer Model (IMM), which is rooted in the theoretical concept of spatial interaction, in order to identify the links within these networks and trace their impacts on trade flows. In our aim to investigate horizontal and vertical interdependency among networks we calibrate the interaction model (IMM) for a set of 40 countries, and thereafter examine the influence of shocks such as economic downturns upon the interdependent networks, which in our model are represented as economic, socio-cultural and physical layers. Most importantly, the model allows us to understand the propagation of cascading effects (both positive and negative) at national and global scales

Accessibility and Complex Network Analysis of the U.S. commuting system

Recently practitioners are approaching spatial and environmental planning by adopting methods and tools drawn from Complexity Science. The strength of these methods is not only apparent in their systemic coherence but also in their capacity to consider a variety of components as a whole system. Given this background, the aim of this paper is to apply a methodology, tested for the Italian insular region of Sardinia, to an analysis of commuter accessibility in the United States through an indicator-based strategy. Spatial measures are applied to study the level of accessibility for commuters at the county level. The analysis provides us with an assessment of the accessibility for U.S. commuters and allows for the consideration of spatial planning objectives for U.S. counties

Accessibility, rurality and remoteness: an investigation on the Island of Sardinia, Italy

The dichotomy between rural and urban settings has been used by census systems across the world in order to distinguish areas with high density population from areas with low density and where the primary occupation is connected to the agricultural sector. In this paper we study the level of accessibility, remoteness and rurality for municipalities in Sardinia, Italy. We apply a spatial analysis by means of indicators, such as accessibility for commuters (De Montis, Caschili and Chessa, 2011), the index of relative rurality, the metropolitan-rural interface levels (Waldorf, 2006) and the rurality- remoteness combined classification (Dijkstra and Poelman, 2008). We investigate whether accessibility shows a similar spatial pattern, with respect to remoteness and rurality, and thus we provide an analysis of the Sardinian setting that is of help for policy-makers and planners to understand some of the relevant regional and urban factors that have driven recent developments

Nuraghes and landscape planning: Coupling viewshed with complex network analysis

Recent approaches in landscape planning have prompted interest in the relationships among cultural goods, human settlements, and the environment. In Europe and Italy, scholars and practitioners have used landscape planning tools for the analysis and management of historical landscapes that include elements such as the sense of belonging of local societies to cultural heritage sites. In this paper the authors present a study of prehistoric settlements focusing on the Nuragic system developed on the Pranemuru plain in Sardinia during the Bronze Age. We investigate the hypothesis that the spatial patterns of the Nuraghes obey rules of inter-visibility control over the surrounding territory. We check the inter-visibility thesis by means of a quantitative approach, which integrates GIS based viewshed and complex network analysis. Nuragic inter-visibility is studied through network modelling and assessed with respect to a topological analysis. Results show a hierarchical organisation and not a random structure in the inter-visibility network: hence, consistent rules influenced the construction of Nuragic settlements on the Pranemuru plain. We conclude speculating that inter-visibility cannot be considered the sole factor that influenced the placement of Nuragic towers. The inter-visibility among these towers is plausibly connected with the presence of other human and natural resources

Accessibility and rurality indicators for regional development

The development of a region is affected, inter alia, by concepts linked to the ability to displace and reach other locations (accessibility) efficiently and to lagging economic conditions connected to contemporary countryside activities (rurality). These topics and their relationships have attracted the interest of scholars who have scrutinized the implications of accessibility and rurality for policy making and planning. The aim of this paper is to contribute to the theoretical modeling of accessibility and rurality and to develop an empirical study of their spatial patterns, with reference to the municipalities of the region of Sardinia, Italy. We study accessibility through an indicator constructed using a doubly constrained spatial interaction model and propose the Composite Index of Rurality that aims to evaluate rurality in a regional setting employing multivariate analysis. We investigate the spatial dependence of these indicators through general and local spatial autocorrelation analysis to verify the hypothesis that scarcely accessible spatial units are classifiable as rural areas. The results show that, for the case study of Sardinia, this hypothesis is not always true, as some urban areas are not always highly accessible

Overcoming implementation barriers: A method for designing Strategic Environmental Assessment guidelines

Strategic Environmental Assessment (SEA) has been officially introduced in the European Union by the Directive 2001/42/EC (Directive) as a decision support system to ensure environmental and sustainable policies in plan and program making. According to the Directive, SEA should be integrated in and inform planning processes from the early stages, in order to obtain an effective consideration of the environmental concerns. European member states have acknowledged the SEA Directive at different stages through diverse legislative acts. This rather new legislative scenario and the correct application of SEA is still limited and needs to be steered through the dissemination of proper documents, beyond the usual emulation of best practices. In this vein, administrative bodies in charge of SEA management have issued guidelines and manuals in order to address the major difficulties that hinder SEA implementation in the day-to-day practice. This study proposes a methodology that assists responsible agencies and professionals in the design of SEA guidance documents. The proposed methodology uses a comparative approach which builds on the key elements of those documents. We have applied our methodology at European national level and evaluated principles, contents, and effectiveness of those guidelines. Our work is intended to support government agencies as well as practitioners in the design and update of SEA guidelines in a variety of cases, as the general principles that we outline can be applied to any program and plan subject to SEA