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The Hyperloop concept, pod speed competitions and current project developments have recently attracted much publicity. In this paper the transport technology of the vacuumed tube transport project Hyperloop is assessed through a system analysis of its principal aims, functional design, transport capacity and demand in comparison with existing commercial airlines, high-speed rail, and Maglev lines. First, the potential for high-speed long-distance travel demand for Hyperloop based on existing airline transport volumes between major airports in Germany on the one hand, and the proposed Hyperloop link from Los Angeles to San Francisco in California on the other, is assessed in general terms. Second, the technical feasibility of the proposed Hyperloop concept for vehicle design, capacity, operations, propulsion, guidance, energy supply, traffic control, safety, alignment, and construction is discussed in more detail. Third, possible environmental impacts and uncertain investment, operating and maintenance costs for implementation of a Hyperloop line are described. Finally, the risks for further Hyperloop project development and the need for more transparent research are emphasized.

The master plan, design and capacity analysis of the future network timetable and track infrastructure of the project known as Stuttgart 21 (Germany) is reviewed with focus on the methods and results for capacity estimation of the planned through station close to the city center. The methods used and results reported for the capacity analysis of the network timetable and in particular the main through station since the first feasibility studies in 1994, complementing timetabling and operations research analysis in 1997 until the robustness analysis in the scope of the stress test simulations are described in detail in order to identify and discuss the critical issues. The shortcomings of the original approach consisting of a periodic network timetable design, queuing models for the estimation of the waiting probability and queue length for the purpose of timetabling and estimation of the operations quality respectively, as well as multiple stochastic simulations are explained and the consistency of the recent stress test simulations are examined.

Train unit routing problem determines the number of train units needed to carry out involved trips, which is a significant part of railway operation cost. In this paper, we focus on high-speed train unit routing problems, in which maintenance resource constraints both on time and distance are taken into account. Based on a connection network, this paper first proposes a general train unit routing model. Then, the general model is specialized to meet the circulation and maintenance conditions of high-speed train units in China, which is based on a special connection network with a two-day time horizon. A strategy is proposed to reduce the scale of the connection network, which improves the model’s solvability. Furthermore, an extension on multi-depot train unit routing problem is discussed. Finally, numerical experiments based on the real data of Chinese high-speed railway are carried out to verify the effectiveness and efficiency of the proposed mode and method.

Metro transit networks are constantly expanding to meet the growing travel demand that accompanies rapid urban growth. One main disadvantage of metro transport is its heavy reliance on access and egress transport and, hence, on the corresponding transfer facilities. Improvements to these transfer facilities therefore have the potential to increase use of the metro system while possibly alleviating the traffic load on the urban road network. Because bicycle transfer at metro stations—that is, using a bicycle as mode of access to or egress from the metro system—is underused, the determinants of the demand for bicycle transfer are investigated. Results and findings are valuable for designing policies aimed at improving metro ridership and for designing bicycle parking and transfer facilities at metro stations. To this end, several metro stations in Nanjing, China, were analyzed, and two stereotypical metro stations were selected for how well they represented the system. A large-scale survey was conducted on metro travelers' opinions on and use of bicycle transfer facilities, and data were collected on the current attributes of service groups, bicycle parking occupancy, and transfer mode alternatives. Furthermore, metro travelers' (latent) transfer preferences for bicycle rental facilities were investigated. Two transfer choice models were estimated to identify and quantify the determinants for bicycle transfer demand: one focuses on current walk–metro trips, and the other focuses on current bus–metro trips. The explanatory determinants are discussed, and relative weights are computed with multiple linear regression analysis.

For scheduled train services, a trade-off exists between efficiently utilizing the capacity of railway networks and improving the reliability and punctuality of train operations. This paper proposes a new analytical stochastic model of train delay propagation in stations, which estimates the knock-on delays of trains caused by route conflicts and late transfer connections realistically. The proposed model reflects the constraints of signalling system and train protection operations rules. The stochastic variations of track occupancy times due to the fluctuations of train speed in case of different signal aspects are modelled with conditional probability distributions. The model is solved on the basis of a numerical approximation of the Stieltjes convolution of individual independent distributions and can be integrated into a larger computerized decision support tool for timetable design and train dispatching. Having been validated successfully with empirical data, the model is applied for optimizing the station capacity utilization in a case study of the Dutch railway station The Hague Holland Spoor. The model can determine the maximal frequency of trains passing the critical level crossing with a given maximum knock-on delay at a certain confidence level. It is found that when the scheduled buffer time between train paths at the level crossing decreases, the mean knock-on delay of all passing trains increases exponentially.

The development of intermodal container transport is hampered in part by the cost associated with the shunting of trains in marshalling yards, inland and port railway terminals. Many new technologies have been developed in the past decade, but have still not been applied because of high capital investment costs, lack of sufficient market demand and uncertain rates of return. The key for increasing the competitiveness of intermodal container transport by rail is the operation of heavy haul container trains between port and inland railway terminals more frequently with fast, flexible and automatic transhipment, shunting and coupling of container wagons. The operation of self-driven railcars equipped with automatic centre coupling on terminal tracks, which can also be train-hauled on conventional hinterland railway lines, would enable a reduction of shunting and transhipment time and costs in intermodal container terminals by more than 30%.

This special issue is based on a selection of the four best papers from the Third International Seminar on Railway Operations Modelling and Analysis held in Zurich from 11 to 13 February 2009. The papers have been selected and reviewed by Board and other senior members of the International Association of Railway Operations Research (IAROR) and subsequently revised by their authors. The authors and their papers come from universities in Sweden, The Netherlands, Italy, Switzerland and Portugal. They represent valuable contributions to the current state of scientific and professional knowledge in the area of railway operations that can stimulate the broader application and further development of advanced analytical, combinatorial and simulation models.

Railway traffic is operated according to a detailed schedule, specifying for each train its path through the network plus arrival and departure times at its scheduled stops. During daily operations, disturbances perturb the plan and dispatchers take action in order to keep operations feasible and to limit delay propagation. This article presents a thorough assessment of the possible application of an optimization-based framework for the evaluation of different timetables and proactive railway traffic management over a large network, considering stochastic disturbances. Two types of timetables are evaluated in detail: “ regular” and “ shuttle” timetables. The former is the regular plan of operations for normal traffic conditions, while the latter plan is designed to be robust against widespread disturbances, such as adverse weather, track blockage, and other operational failures. A test case is presented on a large Dutch railway network with heavy traffic, for which we compute by microsimulation detailed t...

Railway timetables must provide competitive travel times and at the same time be able to withstand delays, perturbations, and variations in operating conditions without losing functionality, to achieve a high service level during operations. The art of designing such a timetable relies on several performance indicators related to individual train paths (running and dwelling), dependencies between train paths (headways, turning, transferring, etc.), and integrated train paths (corridors, networks). These performance indicators include infrastructure occupation, timetable stability, feasibility, robustness, and resilience. The quality of the timetable design process can be evaluated by the manner in which these performance indicators are dealt with. This paper gives an overview of these performance indicators, their importance in the timetable design, and their interrelations, and proposes four timetabling levels that represent how well the timetable performance criteria are taken into account in the timetable design process of a specific railway.

During real-time traffic management, the railway system suffers perturbations. The task of dispatchers is to monitor traffic flow and to compute feasible rescheduling solutions in case of perturbed operations. The main objective of the infrastructure manager is delay minimization, but the dispatchers also need to comply with the objectives of the train operating companies. This paper presents an innovative optimization framework in order to reschedule trains with different classes of priority, that can be computed statically or dynamically in order to include the needs of different stakeholders. An iterative train scheduling procedure is proposed in order to compute feasible train schedules for an ordered set of priority classes, from the highest one to the lowest one. At each step, the procedure focuses on the current priority class, preserving solution quality from the higher priority classes and neglecting lower priority classes in the optimization of train orders and times. The multi-class rescheduling problem is formulated via alternative graphs that are able to model precisely train movements at the microscopic level of block sections and block signals. Each step of the iterative train scheduling procedure is solved to optimality by a state-of-the-art branch and bound algorithm. The results show an interesting gap between single-class and multi-class rescheduling problems in terms of delay minimization. Each priority class is also evaluated in order to assess the performance of the different rescheduling solutions.

Railway traffic experiences disturbances during operations that cause conflicts between train paths or even deadlock situations. Dispatchers need actions to restore feasibility and limit spreading of delays through the network. To help them in such a task, the dispatching support tool ROMA (Railway traffic Optimization by Means of Alternative graphs) has been implemented in a laboratory environment. This paper reports on enhancements to the underlying train dispatching model as well as to the solution algorithms studied in order to tackle the increased complexity of busy stations with multiple conflicting paths and high service frequencies. Advanced train reordering and rerouting techniques are compared with straightforward rules and the current approach in the Netherlands. Extensive computational studies based on accepted statistical distributions of train delays for Utrecht Central Station assess the effectiveness of the ROMA tool in terms of solution quality and computation time.

Data mining and analysis of standard track occupation data is used to compute accurate actual train delays at stations. Based on historical train describer records the delays can be automatically classified into initial and consecutive ones through comparison of actual with scheduled blocking times. The distributions of running times and dwell times of each line and direction can be estimated conditional on the amount of original delays, route conflicts and factors such as type of rolling stock, peak hours or even weather conditions. The running times of actual trains until the next downstream stations can be predicted at a high precision by means of a new online model whose parameters have been calibrated and tested in the Dutch railway corridor Rotterdam - The Hague.

This paper presents an analytical approach for optimally allocating the buffer times between scheduled trains at railway bottlenecks based on a recently developed probabilistic delay propagation model. The design of the buffer times between consecutive trains in a timetable period is improved by minimizing the sum of weighted knock-on delays of the trains. Closed form expressions have been derived for the optimal buffer times by adopting a weighted exponential distribution model for primary delays. An application example reveals that the derived expressions of the optimal buffer times can be used in the design of railway timetables by incorporating the impact of primary delays and priority of trains.

This paper describes how knowing the source of delays is crucial information to railway infrastructure managers and train operators but assigning a given delay to its causes is very difficult. Actual delays at stations are monitored online using train describer systems and timetable databases, but it is unknown whether for instance a delay has been caused by a slow running train or by a route conflict where a driver had to slow down due to a restricted signal. In particular, delays due to route conflicts are hard to recognize afterwards, although their identification is crucial to assess and optimize the quality of infrastructure capacity allocation. This paper presents the software tool TNV-Conflict that identifies automatically all signaled route conflicts including the critical sections and conflicting trains. The developed tool can be used offline using train describer logfiles containing chronological infrastructure and train description messages. The object-oriented approach already anticipates an online implementation based on real-time messages. The resulting information is used to analyze the number of route conflicts and their effect on capacity consumption and punctuality, to assign knock-on delays to conflicting trains in a non-discriminatory way, and to identify structural route conflicts corresponding to timetable flaws (e.g. infeasible minimum headways, late trains due to preceding bottlenecks, and early trains due to excessive running time supplements). TNV-Conflict provides essential information to improve capacity allocation and construct reliable train paths. An example application on a railway corridor in the Netherlands illustrates the potential of the tool.

In the last years, real-time railway traffic optimization experienced an increasing interest due to the expected growth of traffic and the limited possibilities of enhancing the infrastructure, which ask for a more efficient use of resources and the application of more advanced decision support tools. This paper presents a computerized train dispatching system, called ROMA (Railway traffic Optimization by Means of Alternative graphs), for supporting railway traffic controllers during operations. Innovative scheduling and rerouting algorithms have been developed in order to globally optimize disturbed railway traffic conditions. ROMA can anticipate the evolution of traffic, including the propagation of delays in a regional railway network, and can estimate the effects of different dispatching measures during a period of about 15 minutes ahead. Therefore, ROMA would enable traffic controllers to frequently perform incremental changes to the actual timetable to accommodate changes in traffic patterns due to disturbances, such as train delays and blocked tracks. An extensive computational study is carried out, based on a dispatching area of the Dutch railway network, to show the high potential of our train dispatching system as a support tool to improve punctuality.

This paper evaluates several commonly applied probability distribution models for stochastic train process times, which are based on empirical data recorded in a Dutch railway station, The Hague Holland Spoor. An initial guess of model parameters is obtained by the Maximum Likelihood Estimator (MLE). An iterative procedure is then followed, where large delays are omitted one by one and the distribution parameters are estimated correspondingly using the MLE method. The parameter estimation is improved by minimizing the Kolmogorov-Smirnov (K-S) statistic where of course the empirical distribution is still based on the complete data set. A local search is finally performed in the neighborhood of the improved model parameters to further optimize the estimation. To evaluate the distribution models, we compare the K-S statistic among the fitted distributions with optimized parameters using the one-sample K-S goodness-of-fit test at a commonly adopted significance level of α = 0.05. It has been found that the log-normal distribution can be generally considered as the best approximate model among the candidate distributions for both the arrival times of trains at the platform and at the approach signal of the station. The Weibull distribution can generally be considered as the best approximate distribution model for non-negative arrival delays, departure delays and the free dwell times of late arriving trains. The shape parameter of the fitted distribution is generally smaller than 1.0 in the first two cases, whereas it is always larger than 1.0 in the last case. These distribution evaluation results for train process times can be used for accurately predicting the propagation of train delays and supporting timetable design and rescheduling particularly in case of lack of empirical data.

This paper deals with the traffic engineering aspects of the concept of toll-lanes without grade-separated access/egress lanes in metropolitan areas, where motorways - in general - are characterized by a lot of discontinuities. Toll-lanes are projected with the purpose to offer a congestion-free lane for drivers who are willing to pay for the use of such a facility and a high level of service. A simulation study has been performed in order to assess the impacts of advanced driver support systems on the longitudinal and lateral performance near a motorway segment with a toll-lane situated in the median lane and traffic merging to an off-ramp. The conducted simulations varied in the level of toll-lane use, merging proportion, and system penetration in the vehicle fleet. Results from the simulations show the performance benefits of centralized distance control (CDC) for vehicles entering the merging zone. Negative Impacts on throughput were found with the application of an intelligent speed adopter (ISA) with a speed limit of 90 km/h in the merging zone. The combination of the two systems showed small improvements compared with the do-nothing case. The findings show that the application of toll-lanes in combination with advanced driver support systems odd some additional longitudinal and lateral capacity to the main roadway.

The hinder of approaching trains at railway junctions and in stations due to delayed trains still occupying the route can be minimized by the use of on-board processors that automatically determine the speed and travel time needed until the next main signal that protects the route of a conflicting train. The actual location, speed and distance of the trains to the conflict point are continuously recorded by on-board processors and communicated via GSM-R to other trains in the same area. A decision support system for traffic control identifies in time route conflicts between approaching trains automatically, estimates the remaining travel times and indicates the suitable speed to follow by each of the trains in order to assure seamless merging or crossing. The individual acceleration, braking and speed instructions are transmitted to each train and automatically applied by the on-board processor. The automatic piloting of trains enables maximal use of available track capacity, while guaranteeing minimal train delays.

1. 1. The wax secreted by the chicken uropygial gland consists of esters of long-chain 2,3-n-alkanediols (“uropygiols”). Tissue slices incorporated acetate into the uropygiols, but less rapidly than into the fatty acids. 2. 2. The average chain-length of the labelled fatty acids formed was greater in tissue slices than in cytosol preparations. 3. 3. Slices also incorporated added fatty acids into uropygiols; homogenates did not, but rapidly incorporated heneicosanal, a putative direct precursor of the C23-diol, in the presence of NADPH. 4. 4. The 3H:14C ratio in uropygiols synthesized from [1-14C,2-3H]acetate was higher than that in fatty acids; when [6-14C,6-3H]glucose was the substrate, even higher ratios were observed.

A factorial experiment was used to determine the nature of the effects of pH, [taurocholate] and [Ca2+] on the rate of hydrolysis of long-chain triglycerides by pig pancreatic lipase. A stable emulsion of triolein was used as substrate. Statistical analysis showed that there were significant interactions between the three factors. Under the particular conditions of substrate and emulsion used, the following effects were found: In the presence of taurocholate and calcium ions the rate of hydrolysis increased in a non-linear fashion from pH 7.5 to 9.5. The overall effect of [taurocholate] in the presence of calcium ions showed an optimum at about 6.9 mM (0.37%, w/v). [Ca2+] showed a similar optimum at about 40 mM. Although there was interaction between pH and [taurocholate], the plots of reaction rate vs. pH had the same general shape and position on the pH axis for all values of [taurocholate]. There was pronounced interaction between pH and [Ca2+]; optimum [Ca2+] was highly dependent on pH, and the reaction rate at higher pH values was highly dependent on [Ca2+]. The interaction between [Ca2+] and [taurocholate] involved an exponential function of both.

1. 1. Respiring cell-free baker's yeast extracts have been prepared by 10-sec high-speed mechanical disintegration. 2. 2. Increasing the disintegration period reduces the oxidate ability of the extracts. 3. 3. Whole extracts have a low blank respiration at or above pH 7·4. At pH 6·5–7·1 a high blank respiration is found. Addition of small amounts of ATP or A–5–P to the blank at pH 7·4 also induces this high respiration. 4. 4. The blank respiration is due to catabolism of polysaccharide. The R.Q. of the reaction is about 1 or sometimes higher. Considerable amounts of pyruvate and acetate are formed, but these are insufficient to account for either carbohydrate disappearance, O 2 uptake, or CO 2 formation. Some pentose formation occurs. 5. 5. Various acids of the Krebs tricarboxylic acid cycle are oxidized by the extracts, succinate most and malate least rapidly. 6. 6. Quantitative balances of the metabolism of each of the Krebs cycle acids show that they can largely be accounted for by the reactions of the cycle. Only small amounts of citrate are formed from oxaloacetate, acetate and CoA. Considerable amounts of glutamate are formed from α-ketoglutarate but not from citrate. 7. 7. The results are discussed in the light of the Krebs cycle being a major pathway of yeast respiration. Other pathways exist and may account for the high blank respiration observed under certain conditions.

1. 1. Some changes in the structure and metabolism of yeast cells which occur on freezing with solid CO2 are described. 2. 2. CO2-frozen cells, besides being permeable to addrd organic acids, lose organic acids, amino acids, protein, carbohydrate, coenzymes and inorganic salts when washed with water or buffer. 3. 3. The ability of such cells to respire ethanol and succinate may not be a reliable guide to the normal metabolism of these substrates, since the response to varying degrees of temperature-shock differs according to the strain of bakers' yeast used. 4. 4. Freezing reduces the amount of sedimentable material in cell-free extracts prepared by ultra-rapid shaking. In this respect, the effects of freezing resemble those obtained by disintegrating fresh cells for longer periods. Partial solubilization of granular fumarase, aconitase, and ethanol and malic dehydrogenases occurs, and aconitase is partially inactivated. 5. 5. The coenzyme-independent ethanol and malic dehydrogenase activities found in extracts of fresh yeast are lacking in extracts of frozen yeast. The possibility of coenzyme-binding, the disruptive action of thermal shock and the evidence for the participation of the tricarboxylic acid cycle in acetate oxidation by bakers' yeast, are discussed.

1. 1. Stomach oils found in chicks of these two species differed from stomach oils of other petrels in consisting largely of glycerides. Free or esterified cholesterol was also present in considerable amounts. In one specimen of Pterodroma macroptera, wax esters, consisting mainly of monene fatty acids and alcohols, constituted about 6 per cent of the lipid. 2. 2. The stomach oils generally resembled the diet lipid in lipid class composition and fatty acid composition of individual classes. Stomach oils may be residues left by slow digestion. 3. 3. The fatty acid compositions of adipose tissue and liver triglycerides varied partly with the tissue, concerned and partly with the species or its diet. In these birds, synthesis seems a less important source of fatty acids than dietary lipid.

1. The uropygial gland wax of the mallee fowl contained mainly C14 and C16 acids and erythro 2,3-octa-decanediol. No threo diols are odd-numbered acids or diols were detected. A small amount of primary alcohols was present 2. Wax from the stubble quail contained C11 C20 acids and C14 C24 diols (mainly erythro isomers). 3. The data were compared with those reported for the chicken, turkey and green pheasant. The proportions of odd-numbered fatty acids and odd-numbered diols are similar within species. Some birds may have two distinct stereo-specific enzyme systems for biosynthesis of diols.

Incidents and waiting for train connections are registered by dispatchers as sources of train delays, but route and headway conflicts are not always clearly recognized. Moreover, traffic management and route setting are the primary task of dispatchers and signallers, whilst monitoring and incident registration is not allowed to take up too much of their time. This paper describes a tool that automatically and without discrimination identifies route conflicts and the train numbers involved. It is based on standard train describer and infrastructure messages recorded on the Dutch railway network. The logic of these messages is captured in a coloured Petri net (CPN) model on which a prototype tool for route conflict identification and estimation of knock-on delay has been developed.

1. 1. Wax esters of eight more Anseriformes have been shown to contain simple mixtures of the following series of acids: dimethyl-hexanoic (A) and -heptanoic (B); trimethyl-octanoic (C) and -nonanoic (D); tetramethyl-decanoic (E) and -undecanoic (F); pentamethyl-dodecanoic (G) and -tridecanoic (H). E, F, G and H were obtained from the grass whistling duck, and mass spectra of G and H indicated that the methyl substituents were at positions 2, 4, 6, 8 and 10. 2. 2. Other Anatidae investigated were: Hawaiian goose (C, D, E), European wigeon (A, B), Chiloe wigeon (A, B, C), redhead and harlequin duck (B, C, D, E), smew (C, D). The major alcohol in each species was octadecanol. 3. 3. The crested screamer (family Anhimidae) had only n-acids, mainly C12 and C14, and mainly n-C14, C15 and C16 alcohols. The resemblance of these wax esters to those of the magpie goose is striking.

1. 1. Homogenates of chicken uropygial glands esterified added uropygiols ( 2,3-n- alkanediols ) with added and endogenous fatty acids. The reaction was stimulated by addition of ATP and CoA. 2. 2. The best substrates tested for esterification were 1-alkanols; unsaturated primary and saturated secondary alcohols and cholesterol were less effective. 1-Hexadecanol competed with uropygiol for esterification. 3. 3. Homogenates of turkey glands behaved similarly and esterified both threo and erythro uropygiols. Lack of threo isomers in the wax esters of the turkey is therefore not due to incompetence in the esterification system.

1. 1. Isolated intestinal mucosa incorporated labelled palmitate, stearate, oleate, or linoleate into ester lipids to widely different extents, depending on the fatty acid, ester lipid class and animal species. 2. 2. In lamb intestine, incorporation into triglyceride, the major product, decreased in the order: oleate, palmitate, stearate, linoleate; very little cholesterol ester was formed. 3. 3. In rat intestine, incorporation into triglyceride was even more dependent on fatty acid structure, and decreased in the order: palmitate, oleate, linoleate, stearate; cholesterol ester formation was significant with oleate and linoleate. 4. 4. The differences in behaviour between fatty acids probably imply fatty acid specificity in the enzymes involved in ester synthesis.

1. 1. All the recognized egg white proteins are found in the stomach of the 16 day chick embryo. 2. 2. Ovalbumin, serum albumin, ovomucoid and the transferrins are found in the intestine. 3. 3. Pre-albumins appear in the earliestplasma examined (11 days). The level of pre-albumins is highest between the sixteenth and nineteenth day. 4. 4. The pre-albumins have been identified as ovalbumins.

1. 1. Wax esters of Australian Anserinae and Anatinae contained the following series of multiple-branched fatty acids: dimethyl-hexanoic (A) and -heptanoic (B); trimethyl-octanoic (C) and -nonanoic (D); tetramethyl-decanoic (E) and -undecanoic (F); pentamethyl-dodecanoic (G) and -tridecanoic (H). The methyl groups have been assigned tentatively to positions 2, 4, 6, 8 and 10. In each species the major alcohol was octadecanol. 2. 2. In the Anserinae, the black swan produces A, B and C, the Cape Barren goose C and D, and the freckled duck B to F. 3. 3. The mountain duck, like two other Tadornini, produces mainly C and D. The wood duck and green pygmy goose (Cairinini) produce A and B, although the latter species also has 30 per cent n- acids , mainly C10. The musk duck has mainly E and F, with smaller amounts of G and H. 4. 4. The magpie goose lipids consisted of squalene (87 per cent) and wax esters (23 per cent) composed mainly of n- C 10 fatty acid and n- C 10 , C11 and C12 alcohols.

1. 1. The lipids of the head and blubber oils of a sperm whale and of a giant squid removed from its stomach contained 84, 79 and 49 per cent wax esters, respectively. Triglycerides comprised 16, 21 and 26 per cent. 2. 2. The fatty acids and alcohols which were components of the squid lipids were also found in the whale lipids, but many were selectively located in either head or blubber oil. 3. 3. The sperm whale probably derives all of its fatty alcohol and much of its fatty acid from the diet.

The paper applies principles of dynamic traffic management to solve the train re-scheduling problem faced by railway infrastructure managers during operations. When train operations are perturbed conflicts arise with respect to the scheduled train paths. A detailed mathematical formulation and dispatching algorithms are adopted to re-compute a new timetable of feasible arrival and departure times. The system generates a conflict free schedule with admissible train dynamics and with observance of minimum safety headway distances. Computational experiments on a part of the Dutch rail network show that the adopted rescheduling support system provides better solutions when compared to simple dispatching rules.