“We followed a few years after Mr. Swift. We had to learn the methods of dressed beef and experiment. The methods have been gradually growing. We have perfected them year by year, learning something every year as to how to do the business better.” P.D. Armour, 1889 “... all along this east side of the yards ran the railroad tracks, into which the cars were run, loaded with cattle. ‘And what wil...

It is generally accepted that development of requirement models for real-time systems beneets from formal speciications. In order to be able to evaluate notations for use in the development of real-time software systems, we are performing a comparative review of some selected speciication notations. The study emphasizes the use of the notations in the domain of real-time (control) applications....

For some real world railroad networks, we minimize certain operational cost of train schedules which allow different train types of diverse speed and cost. We use a mixed integer linear programming approach to model this train scheduling problem. For practical problem sizes, it is impossible to directly solve the resulting MIPs within a reasonable amount of time. However, a decomposition approa...

A Monte Carlo train over-speed derailment model for risk assessment is developed based on the derailment coefficient (wheel lateral and vertical force ratio). The model considers a one lump train negotiating on curved tracks or tangent tracks. The derailment coefficients for these two situations are calculated and the probabilities of train derailment are obtained to enhance a large scale Monte...

This study estimates returns to density in the U.S. Railroad industry using a cost function with commodity-specific outputs and explores implications for differential pricing. We find that large economies persist railroad industry, suggesting marginal pricing would not come close recovering costs. Increased freedom from deregulation has enabled railroads retain relatively competitive shippers f...

This article presents an application of the Discrete Event System Specification (DEVS) framework to the design and safety analysis of a real-time embedded control system, a railroad crossing control system.The authors employ an extension of the DEVS formalism, real-time DEVS (RT-DEVS), which has a sound semantics for the specification of real-time systems in a hierarchical modular fashion. The ...

The most recent valuation of the financial condition of the railroad retirement system reveals that an existing actuarial deficiency will become more pronounced over time unless corrective action is taken. After projecting the progress of the fund under present law and certain assumptions about the future, the Railroad Retirement Board has concluded that the present value of benefits can be mai...

The Office of Research and Development of the Federal Railroad Administration (FRA) is sponsoring a revenue service demonstration of Advanced Train Systems featuring new technologies for improving safety and efficiency in freight train operations. The project, which commenced in 1999, is part of the Rolling Stock Program Element in FRA’s Five-Year Strategic Plan for Railroad Research, Developme...

We develop an effective representational and inferential framework for fully deadline-coupled, time-situated problem solving. Our effort is to model an agent in a tight and rigid deadline situation, in need of successfully formulating and executing a deadline-feasible plan of action as the world around the agent continues to change. We highlight the severe time-pressure under which the agent mu...

Since the late 1990s the debate in The Netherlands on the transport of hazardous materials by rail has intensified. The reason for this debate is the fact that most of the Dutch railway nodes are located in city centres. Risk is described by a formula in which the probability of an accident is multiplied by its effect. Although the probability might not be large, the effects of an accident can ...