A co-evolutionary algorithm for train timetabling

Train timetabling for a double-track urban rail transit line under dynamic passenger demand

Scheduling local and express trains in suburban rail transit lines: Mixed–integer nonlinear programming and adaptive genetic algorithm

Modeling the first train timetabling problem with minimal missed trains and synchronization time differences in subway networks

The aim of the train timetabling problem is to find a conflict free timetable for a set of passenger and freight trains along their routes in an infrastructure network. Several constraints like station capacities and train dependent running and headway times have to be satisfied. In this work we deal with large scale instances of the aperiodic train timetabling problem for the German railway network. The problem is modelled in a classical way via time discretised networks, its Lagrange-dual is solved by a bundle method. In order to handle the enormous number of variables and constraints dynamic graph generation and dynamic rolling horizon techniques are employed.

A new method is proposed for single-track railway freight train timetable with two-stage solution of train scheduling problem. The method describes train scheduling problem in matrix with the "signaling block" concept. The matrix represents entire block occupancy of trains between inter-stations and internal-stations while decomposing individual train occupancy, making optimization method more flexible in design and use. The "two-stage solution" refers to that of train timetable with "conflict solution" and "timetable optimization." At the beginning, related data for trains are entered to build the initial timetable, which is then transferred and saved as the matrix format. All conflicts between interstations and internal-stations are located; solutions are made with manual scheduling to generate a feasible timetable. In the second stage, departure and stop time of freight trains, and passenger trains if necessary, are adjusted with Fuzzy system. Before optimization, storage is made in ascending amount of extra-time percent in freight train schedule. Execution is made subject to pre-ordered results during optimization for computer program acceleration of current manual spotting solution to find reasonable and feasible solution. The two-stage method also takes less time than the regular railway timetable design methods in cost saving of manual labor and providing higher operation performance and efficiency.

In recent years, with the global energy shortage and severe environmental deterioration, railway transport has begun to attract great interest as a green transportation mode. One of the vital means to realize social sustainable development is to improve railway transportation systems, in which providing a demand-oriented train timetable with a higher service level is the most viable method. A demand-oriented train timetable problem generally deals with passengers’ train-choice decisions according to the queue principle, but it is not adapted to rail systems, such as China’s, where passengers usually book tickets a few days in advance by telephone or online instead of going to stations. This paper is devoted to modeling and solving the demand-oriented train timetabling problem integrated with passengers’ train-booking decisions. Firstly, a bi-level programming model is formulated for their integrated optimization on a rail network. Its upper-level model is to optimize train arrival and departure times at each visited station with the aim of reducing passengers’ total travel cost, while its lower-level model aims to determine passengers’ train-booking behavior using the user equilibrium theory. Then, a priority-based heuristic algorithm is designed to solve this model. It has two main steps at each iteration: one is to determine the number of passengers booking each train with a given train timetable, and the other is to improve the current train timetable based on the valuable information of passenger train-booking decisions. The performance, convergence, and practicability of the proposed method were analyzed based on the Changsha–Zhuzhou–Xiangtan intercity rail in China. Experimental results show the proposed method can effectively reduce the travel cost for passengers, creating a greater passenger demand for railway travel, which is beneficial to the sustainable development of railway systems and even society.

Timetable Optimization for High-Speed Trains at Chinese Railways

Startle eyeblink modification was measured in 20 relatively asymptomatic medicated schizophrenia outpatients and 18 matched controls in order to test for deficits in early and later stages of attentional processing during a memory-load version of the Continuous Performance Test. Participants viewed a series of digits and pressed a button after the digit 7 of each 3-7 sequence. On some trials, a startling noise burst was presented either 120 or 1200 ms following cues that a response might be needed soon (the digit 3) and also following noncues. Controls showed greater startle inhibition at 120 ms following cue than noncue prepulses, whereas patients showed equal inhibition to both, suggesting a deficiency in allocation of controlled attentional resources in early stages of processing. The patients, however, did show large startle inhibition at 120 ms when a distracting stimulus accompanied the task-relevant cue, unlike the controls, who ignored the distracting stimulus. In contrast, both groups showed equal startle inhibition 1200 ms following cue and noncue prepulses, indicating that later modality-specific attention processes are not impaired in patients during this paradigm. Both groups also showed equal inhibition at 120 ms during passively attended prepulses, suggesting that automatic attentional processes were not impaired in these patients.

In the design process of a mechanism, the dynamic behavior plays an important role. It could be the cause of unexpected high dynamic forces in later stages when it is not considered in the early stage of the design process. High forces could produce high stresses and high vibration levels. Several studies have been carried out in this area; however, only a few consider structural criteria and the eigenfrequencies in the early stage of the process. Low forces and an adequate structure should lead to good dynamic behavior. In this work, we present a method to synthesize function generator four-bar linkages that takes into account structural criteria in a joint-forces minimization-maximization problem. Its objective function is the reaction force on the mechanism joints. The problem’s constraints are the maximum stress on the links, the first eigenfrequency of the mechanism and the deflection of the crank and the rocker. With this method, the links’ lengths and cross-sectional areas of the mechanism are obtained for a given task. As condition, we assumed that the crank rotates with constant angular speed and its shaft works as a torsional spring. Moreover, the rocker moves a body with constant inertia. The resultant mechanisms are compared with those obtained with a traditional crank-rocker synthesis method, according to VDI 2130. To compare both methods, the maximum force, maximum stress, deviation of the rocker angle at its dead-center positions and RMS vibration of the crank and rocker of each mechanism are calculated using MSC ADAMS™. The results show that the mechanisms obtained with our method have better stress and vibratory levels than those obtained with a traditional approach.

Form perception from coherent motion is an important aspect of vision. Representations of one-, two- and three-dimensional forms have been found at various stages of cortical processing using random-dot stimuli, whereas representations of biological objects like a walking human being concentrate at higher stages of processing. The perception of biological objects can be induced by sparse dot stimuli that consist of a few dots that mark the joints of the human body [G. Johansson (1973) Percept. Psychophys., 14, 201-211]. In the present study, we aimed to investigate whether neurons in early visual areas that respond to bars and edges defined by luminance contrast also signal bar-like objects from sparse dot stimuli. We studied single neurons with rows of 3-24 dots that were either collinear or scattered within a rectangular form. These dots were moved coherently on a uniform or dotted background, and human observers perceived them as rigid rods or other bar-like objects. We found neurons in the visual cortex of the awake, behaving monkey that responded to these stimuli and were sensitive to the orientation of these objects as for conventional bars or edges. Stimulus conditions that failed to induce these percepts in human observers also evoked weaker responses or none in these neurons. We found these neurons with increasing frequency in areas V1, V2 and V3/V3A. The results suggest that the visual cortex not only detects biological objects, but also lines and other bar-like objects from sparse dot stimuli, and that this function evolves at an early stage of processing.

An integrated energy-efficient and transfer-accessible model for the last train timetabling problem

Service-oriented train timetabling problem with consideration of women-only passenger cars

Lack of correlation between phonetic magnetic mismatch field and plasma d-serine levels in humans

Event Abstract Back to Event Theta burst stimulation of the dorsolateral prefrontal cortex disrupts attention-based modulation of tactile stimuli at early stages of somatosensory processing D. A. Bolton1* and W. R. Staines1 1 University of Waterloo, Department of Kinesiology, Canada Damage to the dorsolateral prefrontal cortex (DLPFC) impairs gating of irrelevant sensory information at early cortical processing stages. We investigated how transient inhibition of DLPFC impacts early event-related potentials (ERPs) arising from relevant or irrelevant vibrotactile stimuli to the fingertips. Specifically, we hypothesized that suppression of DLPFC using continuous theta burst stimulation (cTBS) would result in a reduction of attention-based modulation of tactile ERPs at parietal electrode sites. Participants received vibrotactile stimulation to the index and little finger on the left hand and reported target stimuli on one digit only (as instructed) in one of three groups (n = 12/group) following: (1) cTBS over F4 (40s; 600 pulses of 3 stimuli at 50Hz repeated at 5Hz using 80% of resting motor threshold for abductor pollicis brevis), (2) sham stimulation, or (3) no stimulation. Early ERP amplitudes (< 200ms post-stimulation) were quantified for attended and non-attended trials (C4/CP4). The P100 was significantly reduced for non-attended versus attended stimuli in both sham and no stimulation groups. Conversely, there was no difference between attended and non-attended ERPs following cTBS. The absence of attentional modulation of early ERPs post-cTBS suggests that the DLPFC contributes to filtering irrelevant somatosensory information at early cortical processing stages. Conference: The 20th Annual Rotman Research Institute Conference, The frontal lobes, Toronto, Canada, 22 Mar - 26 Mar, 2010. Presentation Type: Poster Presentation Topic: Abstracts Citation: Bolton DA and Staines WR (2010). Theta burst stimulation of the dorsolateral prefrontal cortex disrupts attention-based modulation of tactile stimuli at early stages of somatosensory processing. Conference Abstract: The 20th Annual Rotman Research Institute Conference, The frontal lobes. doi: 10.3389/conf.fnins.2010.14.00059 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 28 Jun 2010; Published Online: 28 Jun 2010. * Correspondence: D. A Bolton, University of Waterloo, Department of Kinesiology, Waterloo, Canada, dave.bolton@usu.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers D. A Bolton W. R Staines Google D. A Bolton W. R Staines Google Scholar D. A Bolton W. R Staines PubMed D. A Bolton W. R Staines Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Evoked potential measures of language processing in schizophrenia