Modern graphics hardware can be used to create procedural geometry. Our proposal details an optimized method to form roads and similar 3D objects by cookie-cutting them from slightly oversized polygons. The roads follow spline-like curves on a plane. The curves and their offset variants are cast into an approximated, implicit description. This can efficiently be evaluated within a pixel shader ...

This research investigates the self-organization of surface transportation networks. Using a travel demand model coupled with revenue, cost, and investment models, experiments are run under a variety of parameters on a grid network. It is found that roads, contiguous sections of multiple links operating with similar characteristics, and hierarchies of roads emerge under a broad range of assumpt...

The propagation of traffic congestion along roads is a commonplace nonlinear phenomenon. When many roads are connected in a network, congestion can spill from one road to others as drivers queue to enter a congested road, creating further nonlinearities in the network dynamics. This paper considers the node model problem, which refers to methods for solving for cross-flows when roads meet at a ...

Are roads key to raising living standards in poor rural areas? This study evaluates the impact of the World Bank–financed Viet Nam rural transport project I, a large-scale rural roads rehabilitation project that aims to reduce poverty. The analysis will focus on the welfare impacts of rural roads as an input to policy discussion about how best to allocate scarce public resources for poverty red...

an efficient means of transportation and communication. Societies need to move goods, people, and information throughout the regions they control. Roads also have powerful social, political, and sacred functions. Formal roads are major transformations of the environment. Their patterns on the landscape provide information about the organization of settlements, social interaction, land tenure, r...

Although amphibians have relatively high rates of road mortality in urban areas, the conditions under which traffic threatens the survival of local amphibian populations remain unclear. In the Sandhills region of North Carolina (U.S.A.), we counted living and dead amphibians along two transects (total length 165 km) established on roads in areas with varying degrees of urbanization. We found 26...