Abstract: Microscopic simulation tool kits allow for
consideration of the two processes of railway operations and the
previous timetable production. Block occupation conflicts on both
process levels are often solved by using defined train priorities. These
conflict resolutions (dispatching decisions) generate reactionary
delays to the involved trains. The sum of reactionary delays is
commonly used to evaluate the quality of railway operations, which
describes the timetable robustness. It is either compared to an
acceptable train performance or the delays are appraised
economically by linear monetary functions. It is impossible to
adequately evaluate dispatching decisions without a well-founded
objective function. This paper presents a new approach for the
evaluation of dispatching decisions. The approach uses mode choice
models and considers the behaviour of the end-customers. These
models evaluate the reactionary delays in more detail and consider
other competing modes of transport. The new approach pursues the
coupling of a microscopic model of railway operations with the
macroscopic choice mode model. At first, it will be implemented for
railway operations process but it can also be used for timetable
production. The evaluation considers the possibility for the customer
to interchange to other transport modes. The new approach starts to
look at rail and road, but it can also be extended to air travel. The
result of mode choice models is the modal split. The reactions by the
end-customers have an impact on the revenue of the train operating
companies. Different purposes of travel have different payment
reserves and tolerances towards late running. Aside from changes to
revenues, longer journey times can also generate additional costs.
The costs are either time- or track-specific and arise from required
changes to rolling stock or train crew cycles. Only the variable values
are summarised in the contribution margin, which is the base for the
monetary evaluation of delays. The contribution margin is calculated
for different possible solutions to the same conflict. The conflict
resolution is optimised until the monetary loss becomes minimal. The
iterative process therefore determines an optimum conflict resolution
by monitoring the change to the contribution margin. Furthermore, a
monetary value of each dispatching decision can also be derived.
Abstract: The article discusses multimodal mobility in
contemporary societies as a main planning and organization issue in
the functioning of administrative bodies, a problem which really
exists in the space of contemporary cities in terms of shaping modern
transport systems. The article presents classification of available
resources and initiatives undertaken for developing multimodal
mobility. Solutions can be divided into three groups of measures –
physical measures in the form of changes of the transport network
infrastructure, organizational ones (including transport policy) and
information measures. The latter ones include in particular direct
support for people travelling in the transport network by providing
information about ways of using available means of transport. A
special measure contributing to this end is a trip planner. The article
compares several selected planners. It includes a short description of
the Green Travelling Project, which aims at developing a planner
supporting environmentally friendly solutions in terms of transport
network operation. The article summarizes preliminary findings of
the project.
Abstract: We propose a low-cost uniform analysis framework
allowing comparison of the strengths and weaknesses of the
bicycling experience within and between cities. A primary
component is an expedient, one-page mobility survey from which
mode share is calculated. The bicycle mode share of many cities
remains unknown, creating a serious barrier for both scientists and
policy makers aiming to understand and increase rates of bicycling.
Because of its low cost and expedience, this framework could be
replicated widely, uniformly filling the data gap. The framework has
been applied to 13 Central European cities with success. Data is
collected on multiple modes with specific questions regarding both
behavior and quality of travel experience. Individual preferences are
also collected, examining the conditions under which respondents
would change behavior to adopt more sustainable modes (bicycling
or public transportation). A broad analysis opportunity results,
intended to inform policy choices.
Abstract: Travel demand forecasting including four travel choices, i.e., trip generation, trip distribution, modal split and traffic assignment constructs the core of transportation planning. In its current application, travel demand forecasting has associated with three important issues, i.e., interface inconsistencies among four travel choices, inefficiency of commonly used solution algorithms, and undesirable multiple path solutions. In this paper, each of the three issues is extensively elaborated. An ideal unified framework for the combined model consisting of the four travel choices and variable demand functions is also suggested. Then, a few remarks are provided in the end of the paper
Abstract: Optimization plays an important role in most real
world applications that support decision makers to take the right
decision regarding the strategic directions and operations of the
system they manage. Solutions for traffic management and traffic
congestion problems are considered major problems that most
decision making authorities for cities around the world are looking
for. This review paper gives a full description of the traffic problem
as part of the transportation planning process and present a view as a
framework of urban transportation system analysis where the core of
the system is a transportation network equilibrium model that is
based on optimization techniques and that can also be used for
evaluating an alternative solution or a combination of alternative
solutions for the traffic congestion. Different transportation network
equilibrium models are reviewed from the sequential approach to the
multiclass combining trip generation, trip distribution, modal split,
trip assignment and departure time model. A GIS-Based intelligent
decision support system framework for urban transportation system
analysis is suggested for implementation where the selection of
optimized alternative solutions, single or packages, will be based on
an intelligent agent rather than human being which would lead to
reduction in time, cost and the elimination of the difficulty, by
human being, for finding the best solution to the traffic congestion
problem.