Thesis (M.A. (Industrial Psychology))--North-West University, Vaal Triangle Campus, 2006.

This thesis aims at systematically studying the possibilities of minimizing devastating consequences of high-speed rail vehicle derailments by appropriate measures and features in the train design including the running gear. Firstly, an empirical database is established containing as much relevant information as possible of past incidents and accidents that have occurred at substantial running speeds due to mechanical failure close to the interface between the running gear and the track. Other causes that ultimately brought the train in a derailed condition are also covered. Although various accidental circumstances make each derailment a unique event, certain patterns appear to emerge which lead to several critical vehicle parameters capable of influencing the outcome of a derailment or preventing a derailment to occur. Secondly, the possibility of preventing wheel climbing derailments after an axle journal failure is studied by implementing mechanical restrictions between wheelsets and bogie frame. In this respect, a multi body system (MBS) computer model is developed to account for such an axle failure condition, which is successfully validated on the basis of two authentic passenger car events. In order to study the overall post-derailment vehicle behaviour, in particular the wheelsets’ vertical motion and lateral deviation on sleepers, a comprehensive MBS post-derailment module is developed and implemented in the commercially available software GENSYS. The model detects wheel-sleeper impact conditions and applies valid force resultants calculated through linear interpolation based on a pre-defined look-up table. The table was constructed through exhaustive finite element (FE) wheel to concrete sleeper impact simulations utilising the commercially available software LS-DYNA. The MBS post-derailment module has been validated successfully in several stages, including a correct prediction of the derailing wheelset’s trajectory over ten consecutive sleepers in comparison with an authentic passenger vehicle derailment event. An extensive simulation analysis on the feasibility of utilizing alternative substitute guidance mechanisms attached to the running gear on rail vehicles is presented, as means of minimizing the lateral deviation. Three low-reaching guidance mechanisms attached onto the running gear (bogie frame, brake disc and axle journal box) are analysed in terms of geometrical parameters for a successful engagement with the rail in order to prevent large lateral deviations after twelve different derailment scenarios. Three conventional coupled passenger trailing cars are investigated in terms of lateral deviation and vehicle overturning tendency after derailments on tangent and curved track. This is performed as a function of various vehicle design features and parameters such as: maximum centre coupler yaw angle, carbody height of centre of gravity, coupler height and additional running gear features. In a similar manner, the articulated train concept is investigated in terms of the post-derailment vehicle behaviour as a function of different inter-carbody damper characteristics and running gear features. / QC 20100701

Mit der Einführung des europäischen Zugsicherungssystems ETCS sind durch die umfassenden Telegrammdaten, die zwischen Zug und Strecke ausgetauscht werden, neue Herausforderungen bei der Planung, Projektierung, aber auch Prüfung und Validierung verbunden. Im Rahmen der Dissertation wird ein neuartiges Verfahren zur Validierung sicherheitskritischer Anteile von ETCS-Nachrichten entwickelt. Der Ansatz beruht auf der topologischen Aufbereitung der Nachrichteninhalte in einem vierstufigen Prozess. Das Ergebnis der Aufbereitung erlaubt sowohl den automatisierten Abgleich gegen Referenzdaten als auch eine visuelle Prüfung gegen Topologiepläne. Das Optimierungspotential des Ansatzes bei der Validierung wird im Rahmen einer Erprobung anhand realer Projektdaten bestätigt. Mit der topologischen Aufbereitung werden die komplexen Nachrichteninhalte in eine für den Prüfer erfassbare und zu den Referenzdaten vergleichbare Form überführt. Redundante Nachrichteninhalte werden im Zuge der Aufbereitung erkannt und zusammengefasst, was gleichermaßen zur Minimierung des Prüfaufwands sowie zur Erhöhung des Abdeckungsgrades beiträgt.

In dieser Arbeit sollen die maßgeblichen nationalen Zugbeeinflussungssysteme der Länder Polen (SHP, Radio-Stop, KHP), Slowakei und Tschechien (LS, MIREL VZ1) vorgestellt und miteinander verglichen werden. Der Fokus liegt dabei auf einer funktionellen Betrachtung, wobei auch der technische Hintergrund nicht unberücksichtigt bleibt. Ein Ausblick auf die zukünftigen Bemühungen hinsichtlich ETCS rundet den Überblick ab. / This paper compares the major national train protection systems of Poland (SHP, Radio-Stop, KHP), the Slovak Republic and Czechia (LS, MIREL VZ1). The emphasis is placed on a functional description, while mentioning the relevant technical background where necessary. An outlook on future developments regarding ETCS in the respective countries concludes each chapter.

La plupart des pièces industrielles sont soumises à des chargements multiaxiaux à amplitude variable. La connaissance de la durée de vie résiduelle d'une pièce fissurée, nécessite des modèles de propagation capables de prendre en compte ces deux aspects.<br />Les objectifs de la thèse portent, d'une part, sur l'application d'un modèle incrémental pour simuler la fissuration par fatigue des roues de train sous chargement à amplitude variable, et d'autre part, sur l'enrichissement de ce modèle pour prendre en compte la compression, la contrainte T et la forme semi-elliptique des fissures.<br />Le modèle incrémental repose sur l'idée qu'en fatigue à grand nombre de cycle, l'avancée instantanée d'une fissure est proportionnelle à l'émoussement plastique de sa pointe. Les équations d'évolution de l'émoussement plastique sont déterminées par Eléments Finis à partir du comportement élastoplastique de la structure fissurée. Deux essais sont nécessaires pour identifier les paramètres du modèle, un essai de comportement élastoplastique cyclique du matériau et un essai de fissuration en fatigue à amplitude constante. Les calcul de propagation ont montré que le modèle reproduit fidèlement tout les phénomènes observés en fatigue à amplitude variable : retard après surcharge, accélération après souscharge, interaction entre cycles et histoire de chargement pour les signaux complexe. La compression et la contrainte T ont été ensuite intégrée dans le modèle et validées grâce à des essais de fissuration réalisés sur des éprouvettes prélevées dans une roue de TGV. Enfin le modèle a été étendu en 3D, des essais de fissuration sur fissure semi-elliptique ont été menés sur éprouvettes de flexion 4 points et sur roues à l'échelle 1, l'accord avec les prédictions du modèle est satisfaisant.

The Austin Steam Train Association operates a tourist train on a stretch of track in Texas from Cedar Park to Burnet. The diverse assortment of restored cars, some dating back to the 1920s, is pulled most-recently by a diesel engine, No. 442, as Southern Pacific No. 786, the original steam engine, is in the process of being repaired. The train requires more than $1 million annually to operate and would have folded long ago if not for an all-volunteer crew. ASTA staffs the crew of at least 10-15 people per train 105-110 times per year and has been doing so for more than 20 years. During a ride on the train, passengers see a wide variety of scenery, including some relics with historical significance. Among them are several large chunks of granite which fell of trains shuttling the stone decades ago from Marble Falls to Austin for the construction of the capitol building. Trains also carried granite to Galveston after the infamous hurricane hit. ASTA also provides entertainment inside the train. Themes rides sell out months in advance. Murder mystery trips are always hits but the Wine Flyer is gaining popularity. With a layover in Burnet on the Saturday Hill Country Flyers trips, passengers take time to explore a new city, have lunch and maybe do a little quick shopping. ASTA takes the operation of the train seriously and makes safety a priority. ASTA runs the train with fantastic dedication and perseverance and subsequently, generates a rolling work of history for study by families, first-timers and enthusiasts alike on a weekly basis. / text

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Diese Studienarbeit gibt einen Überblick über ausgewählte Teile des Softwareentwicklungsprozesses für sicherheitsrelevante Applikationen am Beispiel eines videobasierten Zugerkennungssystems. Eine IP-Kamera und ein externer Bildverarbeitungscomputer wurden dazu mit einer speziell entworfenen, verteilten Software ausgestattet. Die in Ada und C geschriebenen Teile kommunizieren dabei über ein dediziertes, UDP-basiertes Netzwerkprotokoll. Beide Programme wurden intensiv anhand verschiedener Techniken analysiert, die in der Norm EN 50128 festgelegt sind, welche sich speziell an Software für Eisenbahnsteuerungs- und überwachungssysteme richtet. Eine an der Norm orientierte Struktur mit Verweisen auf die diskutierten Techniken zu Beginn eines jeden Abschnitts erlaubt einen schnellen Vergleich mit den originalen Anforderungen des Normtexts. Zusammenfassend haben sich die Techniken bis auf wenige Ausnahmen als sehr geeignet für die praktische Entwicklung von sicherer Software erwiesen. Allerdings entbindet die Norm durch ihre teils sehr abstrakten Anforderungen das am Projekt beteiligte Personal in keinster Weise von seiner individuellen Verantwortung. Entsprechend sind die hier vorgestellten Techniken für andere Projekte nicht ohne Anpassungen zu übernehmen. / This paper intends to give an overview of selected parts of the software development process for safety-relevant applications using the example of a video-based train detection. An IP-camera and an external image processing computer were equipped with a custom-built, distributed software system. Written in Ada and C, the system parts communicate via a dedicated UDP-based protocol. Both programs were subject to intense analysis according to measures laid down in the EN 50128 standard specifically targeted at software for railway control and protection systems. Preceding each section, a structure resembling the standard document with references to the discussed measures allows for easy comparison with the original requirements of EN 50128. In summary, the techniques have proven to be very suitable for practical safe software development in all but very few edge-cases. However, the highly abstract descriptive level of the standard requires the staff involved to accept an enormous personal responsibility throughout the entire development process. The specific measures carried out for this project may therefore not be equally applicable elsewhere.

L’étude des pratiques de prévention en santé publique laisse voir que les innovations basées sur des données probantes ne sont pas toujours les plus utilisées (Ringwalt et al. 2002, Wandersman et Florin 2003). Dans la volonté de mettre de l’avant non seulement une innovation basée sur des données probantes, mais aussi une innovation réellement utile à la communauté que le Centre de liaison sur l’intervention et la prévention psychosociale (CLIPP) a mis sur pied en 2006 le programme de formation par agents multiplicateurs «Agir en milieu de garde» ayant pour principal objectif la prévention des mauvais traitements chez les jeunes enfants. La présente étude vise à décrire l’implantation de ce programme dans les services de garde en milieu familial du Québec et à examiner les processus qui ont influencé cette implantation. Les résultats exposent le niveau d’implantation sur deux plans : le dosage et la fidélité. L’étude des processus d’implantation permet de documenter l’influence sur le niveau d’implantation de quatre types de facteurs : individuels, organisationnels, communautaires et propres à l’innovation ainsi que l’influence des interactions entre ces différents facteurs. / The study of Public Health prevention practices suggests that evidence-based innovations are not always the most widely used (Ringwalt et al. 2002, Wandersman and Florin 2003). In 2006, in a strong desire to put forward not only an innovation based on evidence, but also an innovation really useful to the community, the Centre de liaison sur l’intervention et la prévention psychosociale (CLIPP) created “Agir en milieu de garde”, a trained-the-trainers program based whose primary objective was prevention of infant abuse. The present study’s goal is to describe the program’s implementation in home day care centers in Quebec and examine the processes that have an influence on this implementation. The results establish the level of implementation on two specific aspects : dosage and adherence. By studying implementation processes, the present study was able to document how the level of implementation is influenced by four different types of factors :individual, organizational, community and specific to innovation. This study also looked at how the interactions between these four types of factors can influence the implementation.

Train traffic control is a complex task in a dynamic environment. Different actors have to cooperate to meet strong requirements regarding safety, punctuality, capacity utilization, energy consumption, and more. The GMOC model has been developed and utilized in a number of studies in several different areas. This thesis describes GMOC and uses train traffic control as the application area for evaluating its utility. The GMOC model has its origin in control theory and relates to concepts of dynamic decision making. Human operators in complex, dynamic control environments must have clear goals, reflecting states to reach or to keep a system in. Mental models contain the operator’s knowledge about the task, the process, and the control environment. Systems have to provide observability, means for the operator to observe the system’s states and dynamics, and controllability, allowing the operators to influence the system’s states. GMOC allows us to constructively describe complex environments, focusing on all relevant parts. It can be utilized in user-centred system design to analyse existing systems, and design and evaluate future control systems. Our application of GMOC shows that automation providing clear observability and sufficient controllability is seen as transparent and most helpful. GMOC also helps us to argue for visualization that rather displays the whole complexity of a process than tries to hide it. Our studies in train traffic control show that GMOC is useful to analyse complex work situations. We identified the need to introduce a new control strategy improving the traffic plan by supporting planning ahead. Using GMOC, we designed STEG, an interface implementing this strategy. Improvements that have been done to observability helped the operators to develop more adequate mental models, reducing use of cognitive capacity but increasing precision of the operative traffic plans. In order to improve the traffic controllers’ controllability, one needs to introduce and share a real-time traffic plan, and provide the train drivers with up-to-date information on the surrounding traffic. Our studies indicate that driver advisory systems, including such information, reduce the need for traffic re-planning, improve energy consumption, and increase quality and capacity of train traffic. / KAJT / FTTS