Neues verkehrswissenschaftliches Journal - Ausgabe 22
Neues verkehrswissenschaftliches Journal - Ausgabe 22

Author: Weiting Zhao

Publisher: BoD – Books on Demand

Published: 2018-01-23

Total Pages: 142

ISBN-13: 3746035015

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With the increasing traffic demand and limited infrastructure expansion, railway operation becomes more susceptible to the operational disturbances. In order to ensure a robust railway operation, a proactive dispatching algorithm in dynamic circumstances under the consideration of random disturbances is necessary. In this study, an operational risk map will be firstly produced: by simulating considerable amount of disturbed scenarios generated in a Monte-Carlo scheme and calculating the corresponding expected negative impacts, different levels of operational risk will be assigned to each block section in the investigated network. Within a rolling time horizon framework, conflicts are detected with the inclusion of risk-oriented disturbances in each block section, and the near-optimal dispatching solutions are calculated by using Tabu search algorithm. Finally, three indicators including total weighted waiting time, the number of relative reordering and average absolute retiming, are chosen to testify the effectiveness and advantages of the proposed dispatching algorithm. The sensitivity analysis of dispatching-related parameters is conducted afterwards to investigate the most appropriate relevant parameters for the specific studied area. The proposed algorithms are expected to be capable of automatically producing near-optimal and robust dispatching solutions with sufficient punctuality achieved.

Neues verkehrswissenschaftliches Journal - Ausgabe 18
Neues verkehrswissenschaftliches Journal - Ausgabe 18

Author: Jiajian Liang

Publisher: BoD – Books on Demand

Published: 2017-08-18

Total Pages: 190

ISBN-13: 3744840107

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A railway system is a complex system. With the assistance of a railway operation control system, railway traffic is managed according to an operation plan. During the operation process, especially in railway networks with complex topology and high traffic flow, disturbances are likely to occur, which may result in severe deviations of train movements from the pre-designed operation plan. Once conflicts have occurred or potential conflicts between trains have been detected, suitable dispatching actions should be executed to minimize the negative impacts of the disturbances. In order to support dispatchers, a dispatching optimization algorithm was developed in this dissertation. In the development of dispatching models, two aspects need be considered: modelling of railway operation and the dispatching optimization algorithm. The former is indispensable to accurately assess the impact of disturbances, and the latter is employed to find solutions with minimal impact. In order to balance accuracy and computation complexity a multi-scale simulation model was developed in this dissertation. Dispatching optimization is a typical combinatorial optimization problem, and exhaustive search becomes impractical when there is a large set of possible dispatching solutions. To speed up the search, a widely used metaheuristic algorithm-tabu search - was adopted as the basis of the dispatching optimization algorithm. This dissertation addressed both multi-scale simulation and dispatching optimization in railway operation.

Neues verkehrswissenschaftliches Journal - Ausgabe 19
Neues verkehrswissenschaftliches Journal - Ausgabe 19

Author: Di Liu

Publisher: BoD – Books on Demand

Published: 2017-07-11

Total Pages: 202

ISBN-13: 3744841030

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Rail-bound transport in urban areas plays an important role in public transport. Given its urban setting, urban rail-bound transport can be significantly influenced by the interfering road traffic around it. Considering the capacity and operation quality of urban rail-bound transport influenced by road traffic in various urban mixed traffic zones, it'very important to investigate and include the road traffic influences for capacity research on urban rail-bound transport. In this dissertation, two approaches are developed to model the road traffic influences according to the analysis of the interactions between urban mixed traffic in various mixed traffic zones. As an important intermediate result, the newly-developed waiting time function is determined to adapt to an urban rail-bound system with consideration of external influences. Furthermore, an algorithm is developed in the model with an event-driven system to simulate the interactions among urban mixed traffic in various mixed traffic zones. This algorithm is used to assess the significance of mixed traffic impacts and derive the primary results for capacity research.

Neues verkehrswissenschaftliches Journal - Ausgabe 26
Neues verkehrswissenschaftliches Journal - Ausgabe 26

Author: Yong Cui

Publisher: BoD – Books on Demand

Published: 2018-10-25

Total Pages: 198

ISBN-13: 3752855207

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Simulation methods are widely-used in the field of railway planning and operations. However, the various tools are all lacking with respect to the standards they utilise as well as their published interfaces. For an end-user, the basic mechanism and the assumptions built into a simulation tool are unknown, which means that the true potential of these software tools is limited. One of the most critical issues is the lack of the ability of users to define a sophisticated workflow, integrated in several rounds of simulation with adjustable parameters and settings. This book develops and describes a user-based, customisable platform. As the preconditions of the platform, the design aspects for modelling the components of a railway system and building the workflow of railway simulation are elaborated in detail. Based on the model and the workflow, an integrated simulation platform with open interfaces is developed. Users and researchers gain the ability to rapidly develop their own algorithms, supported by the tailored simulation process in a flexible manner. The productivity of using simulation tools for further evaluation and optimisation will be significantly improved through the user-adaptable open interfaces.

Demography and Infrastructure
Demography and Infrastructure

Author: Tobias Kronenberg

Publisher: Springer Science & Business Media

Published: 2011-02-09

Total Pages: 259

ISBN-13: 9400704585

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Population ageing has been going on for many decades, but population shrinking is a rather new phenomenon. The population of Germany, as in many other countries, has passed a plateau and is currently shrinking. Demographic change is a challenge for infrastructure planning due to the longevity of infrastructure capital and the need to match supply and demand in order to ensure cost-efficiency. This book summarises the findings of the INFRADEM project team, a multidisciplinary research group that worked together to estimate the effects of demographic change on infrastructure demand. Economists, engineers and geographers present studies from top-down and bottom-up perspectives, focusing on Germany and two selected regions: Hamburg and Mecklenburg-Western Pomerania. The contributors employed a broad range of methods, including an overlapping-generations model for Germany, regional input-output models, an energy systems model, and a spatial model of the transportation infrastructure.

New Serial Titles
New Serial Titles

Author:

Publisher:

Published: 1974

Total Pages: 1614

ISBN-13:

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A union list of serials commencing publication after Dec. 31, 1949.