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In urban areas around the world, increasing motorization and growing travel demand make the urban transportation sector an ever-greater contributor to local air pollution and greenhouse gas emissions. The situation is particularly acute in developing countries, where growing metropolitan regions suffer some of the world’s highest levels of air pollution. Policies that seek to develop and manage this transportation sector—to meet rising demand linked to economic growth and safeguard the environment and human health—have had strikingly different results, with some inadvertently exacerbating the traffic and pollution they seek to mitigate. This paper provides an overview of the findings of the recent literature on the impacts of a host of urban transportation policies used in developed and developing country settings. The paper identifies research challenges and future areas of study of transportation policies, which can have important, long-lasting impacts on urban life and global climate change.

A simultaneous iterative procedure for the fixed-interface component modal synthesis (CMS) method is developed in this paper toward fast calculating the modal parameters and ROM of a large-scale and/or complicated structure. Different from existing iterative fixed-interface CMS methods, in the proposed iterative scheme, an eigenvalue independent matrix, whose columns’ projections in the exact reduced space are the global eigenvectors of interest, is chosen as the iterative term and then used as a Ritz basis to generate reduced system matrices. Consequently, all the required modes can be solved simultaneously and a ROM can be derived after one round of iterations. For reference, an implementation is given together with computational considerations. Compared with other methods for solving modal parameters and/or model order reduction, the proposed method has such merits as high computational efficiency, especially for reanalysis tasks and parallel programming. A numerical example is provided to illustrate and validate the proposed method.

For evaluating the stress gradient, a mathematical technique based on the stress field of lower-order C0 elements is developed in this paper. With nodal stress results and location information, an overdetermined and inconsistent equation of stress gradient is established and the minimum norm least squares solution is obtained by the Moore-Penrose pseudoinverse. This technique can be applied to any element type in comparison with the superconvergent patch (SCP) recovery for the stress gradient, which requires the quadratic elements at least and has to invert the Jacobi and Hessian matrices. The accuracy and validity of the presented method are demonstrated by two examples, especially its merit of achieving high accuracy with lower-order linear C0 elements. This method can be conveniently introduced into the general finite element analysis programs as a postprocessing module.