The goal of this paper is to analyse semantics of algorithms with explicit continuous time with further aim to nd approaches to au-tomatize model checking in high level, easily understandable languages. We give here a general notion of timed transition system and its formula representation that are suucient to deal with some known examples of timed algorithms. We prove that the general semantic...

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...

Semantic query optimization can dramatically speed up database query answering by knowledge intensive reformulation. But the problem of how to learn the required semantic rules has not been previously solved. This chapter presents a learning approach to solving this problem. In our approach, the learning is triggered by user queries. Then the system uses an inductive learning algorithm to gener...

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...

Purpose In comparison to North America, railway companies in Europe are confronted with strong economic issues in running their wagonload traffic. The purpose of this paper is an analysis how infrastructural and institutional differences affect planning issues and economic efficiency. Method A particular decision problem from railway freight traffic, the Railroad Blocking Problem (RBP), is cons...

Using modeling and simulation users can apply realistic interactions with their synthetic environments representing real world. In this study the synthetic environment is a hardware railroad model representing a miniature replica of a full-size railroad system under study. The hardware model is tested by means of real-time adaptive software simulator consisting of two subsystems: the virtual ra...

Attractive train schedules are quite important for the success of public rail transport. We consider schedules which are repeated after some xed time period. Periodicity is a well accepted, convenient attribute of all major railroad systems. Since trains share the public railroad network, we have to handle many connicting demands. Increasing competition from transportation alternatives as well ...

As a next generation of Global System for Mobile Communications – Railway (GSM-R), 3rd Generation Partnership Program (3GPP) Long Term Evolution (LTE)/ LTE-Advanced (LTE-A) is considered for railroad wireless communication, i.e., LTE-Railway (LTE-R). Railroad wireless communication has its own requirements and functions since railroad wireless communication is very closely related to safety. In...

In the 1930s, amidst concern about the ability of existing pension programs to provide former railroad workers with adequate assistance in old age, Congress established a national Railroad Retirement system. This system is primarily administered by the Railroad Retirement Board (RRB), which is an independent federal agency charged with providing benefits to eligible employees of the railroad in...