Analysis of Financing Options for Transportation

This paper reviews and analyzes various innovative Financing tech­niques for highway and transit. With federal support diminishing and transportation needs growing, agencies are seeking new ways to meet this crisis. The techniques discussed fall into the four broad categories of: (1) charges on benefiting properties; (2) joint venture approaches; (3) user charges; and (4) marketing and merchandising approaches. Charges on benefiting properties recognize that there are specific beneficiaries who gain from transportation improvements and include: connector fees, negotiated investments, special benefit assessment, tax increment finan­cing and impact requirements. Joint ventures with the private sector recognize that it is mutually advantageous for public and private sectors to cooperate on transportation projects and include the techniques of land/air rights leasing, donations for capital improvements and cost shar­ing. User charges are intended as direct payments for services rendered and are classified as motor vehicle taxes and fees, tolls, commercial park­ing taxes and taxes on motor fuels. Marketing and merchandising ap­proaches include advertising and merchandising. None of the techniques are a panacea for transportation finance but where appropriate condi­tions exist, they can be effectively used to finance the growing transpor­tation needs of our natio

Experiments on Roll Waves in Air-Water Pipe Flow

Experiments on air-water two phase flow in inclined pipes have been made, with emphasis on the roll wave regime. The motivation for the work is the improving of 1D flow models for multiphase pipeline transport of oil and gas mixtures. Pressure and liquid fractions are recorded in time, together with video recordings. The results show that large amplitude roll waves have associated pressure jumps across the fronts. Some implications for the flow modelling are discussed

Time-averaged MSD of Brownian motion

We study the statistical properties of the time-averaged mean-square displacements (TAMSD). This is a standard non-local quadratic functional for inferring the diffusion coefficient from an individual random trajectory of a diffusing tracer in single-particle tracking experiments. For Brownian motion, we derive an exact formula for the Laplace transform of the probability density of the TAMSD by mapping the original problem onto chains of coupled harmonic oscillators. From this formula, we deduce the first four cumulant moments of the TAMSD, the asymptotic behavior of the probability density and its accurate approximation by a generalized Gamma distribution

Generalized Master Equations for Non-Poisson Dynamics on Networks

The traditional way of studying temporal networks is to aggregate the dynamics of the edges to create a static weighted network. This implicitly assumes that the edges are governed by Poisson processes, which is not typically the case in empirical temporal networks. Consequently, we examine the effects of non-Poisson inter-event statistics on the dynamics of edges, and we apply the concept of a generalized master equation to the study of continuous-time random walks on networks. We show that the equation reduces to the standard rate equations when the underlying process is Poisson and that the stationary solution is determined by an effective transition matrix whose leading eigenvector is easy to calculate. We discuss the implications of our work for dynamical processes on temporal networks and for the construction of network diagnostics that take into account their nontrivial stochastic nature

Climate change mitigation with technology spillovers

We explore the implications of an increase in clean technology spillovers between developed and developing countries. We build a game of abatements in which players are linked with technology spillovers determined by an initial choice of absorptive capacities by developing countries. We show that, within a non-cooperative framework, the response of clean technology investments in developed countries to an increase in cross-country technology spillovers is ambiguous. If the marginal benefits of these additional abatements are not sufficiently high, developed countries have a strategic incentive to decrease investments. Such a strategic response jeopardizes the initial effects of an increase in technology spillovers on climate change mitigation and decreases the incentives for developing countries to enhance their absorptive capacities