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We present a model that allows us to compare the effects that frictions involved in immigration and international outsourcing have on the skilled–unskilled wage inequality. We show that, for any given level of contractual friction in the production of intermediate goods, the wedge between the wages of the skilled and unskilled workers widens as the frictions in immigration wear out. The skilled–unskilled wage gap, for any given level of friction in immigration, is sensitive to variations in contractual frictions in intermediates that affect international outsourcing.

Purpose – Freeway networks are designed to higher standards and are safer infrastructures as compared to other road types, if properly designed. On the other hand, these facilities are driven at very high speeds and therefore speed and design consistency are essential for achieving safe infrastructure designs. This chapter describes the criteria for speed and design consistency and looks at new tools and criteria for improving freeway safety in new and in existing infrastructures.

Methodology – This chapter describes the criteria to evaluate if there are speed, design and human factors inconsistencies, as well as potential solutions for tackling local deficiencies and speeding issues. As one of the critical issues in freeway safety is represented by run-off-road crashes, a specific section in the chapter is devoted to newly developed design and assessment tools for improving roadside safety. The potential implications of Intelligent Transportation System (ITS) technologies on freeways design and management are also presented.

Findings and Social Implications – The important crash reduction trends observed in the decade 2001–2010 are now slowing down and new actions are required to be coupled with more traditional design checks. The full implementation of cooperative ITS systems is expected to have a very important impact on road safety, but in the short term several safety improvements can be realised: section speed enforcement techniques and high-friction wearing courses have been proven to be extremely effective, as have perceptual measures accounting for human factors principles.

The collection of essays in this volume provides fairly comprehensive analyses of contemporary theoretical and policy issues in international trade. As technological revolution eliminates communications costs and the countries gear towards more open trade regimes through negotiations at the WTO, the world effectively gets smaller. The evolution of research in trade theory and policy has closely followed the trends in global economy. Issues such as how trade affects distribution of income across and within nations, generates resources for growth, leads to bilateral and multilateral cooperation and conflicts, and many others have been picked up and analyzed systematically in various chapters of this volume. Before we go into the details of the relevant sections and constituent chapters, it is worthwhile to emphasize two special features of this volume.

The vehicle–track interaction and the resulting dynamic response of the vehicle involve a number of complex nonlinear problems. Large vertical loads act through a small contact patch leading to very high contact pressures. Transverse loads acting through this contact induce a relative velocity between wheel and rail expressed in non-dimensional form as a creepage. The wheel and rail profiles determine the contact patch shape and affect the ability of the vehicle to run stably. If the yaw stiffness of the axles is too low, the vehicle will become unstable at a relatively low speed; conversely, if the yaw stiffness is too high, the curving behaviour will be adversely affected. The vehicle suspension, especially the secondary suspension, also affects the ride comfort of passengers. Finally, it is shown how the speed profiles of accelerating and decelerating trains can be calculated from basic assumptions about the train power, adhesion and rolling resistance.