An Event-based Simulation Model for Analysing the Utilization Levels of a Railway Line in Urban Area

This paper offers a simulation model for analyzing the utilization levels of a railway line between Edinburgh Waverley and Glasgow Queen Street. Specifically, a segment of this line has been simulated using Simul8 to study the impacts of freight trains on passenger trains. The utilisation levels of this segment have been observed in three scenarios: utilisation existing state where all scheduled passenger trains and a few freight trains are observed; utilisation in future state where more freight trains are input in available time gaps running at their actual speed; and utilisation future state where freight trains are input in available time gaps running at speed equivalent to a passenger train. A decomposition approach is implemented. The results suggest that extra freight trains can be input into the current timetables without impeding the current scenario, allowing a reasonable increase in utilisation of the rail line

Research on Dependences of Railway Infrastructure Capacity

Following the liberalisation of the railway infrastructure, the non-discriminatory approach to each railway undertaking is necessary, including the issue of the train paths provision in terms of the railway infrastructure capacity. Expression and provision of the throughput capacity of the railway network by absolute number of train paths appear to be inadequate and inaccurate at first glance. There are many ways of calculating the capacity of rail infrastructure, as well as several ways of expressing it. The paper describes the testing of the railway infrastructure capacity in a computer based simulation model, which provides results for further research in the area of this issue. Two hypotheses oriented towards the research on the linear dependence of capacity on the number of train paths as well as towards the need for capacity estimation for a whole track or for only one block section are tested

Cost Optimization Modeling for Airport Capacity Expansion Problems in Metropolitan Areas

The purpose of this research was to develop a cost optimization model to identify an optimal solution to expand airport capacity in metropolitan areas in consideration of demand uncertainties. The study first analyzed four airport capacity expansion cases from different regions of the world to identify possible solutions to expand airport capacity and key cost functions which are highly related to airport capacity problems. Using mixedinteger nonlinear programming (MINLP), a deterministic optimization model was developed with the inclusion of six cost functions: capital cost, operation cost, delay cost, noise cost, operation readiness, and airport transfer (ORAT) cost, and passenger access cost. These six cost functions can be used to consider a possible trade-off between airport capacity and congestion and address multiple stakeholders’ cost concerns. This deterministic model was validated using an example case of the Sydney metropolitan area in Australia, which presented an optimal solution of a dual airport system along with scalable outcomes for a 50-year timeline. The study also tested alternative input values to the discount rate, operation cost, and passenger access costs to review the reliability of the deterministic model. Six additional experimental models were tested, and all models successfully yielded optimal solutions. The moderating effects of financial discount rate, airport operation cost, and passenger access costs on the optimal solution were quantitatively the same in presence of a deterministic demand profile. This deterministic model was then transformed into a stochastic optimization model to address concerns with the uncertainty of future traffic demand, which was further reviewed with three what-if demand scenarios of the Sydney Model: random and positive growth of traffic demand, normal distribution of traffic demand changes based on the historical traffic record of the Sydney region, and reflection of the current COVID- 19 pandemic situation. This study used a Monte Carlo simulation to address the uncertainty of future traffic demand as an uncontrollable input. The Sydney Model and three What-if Models successfully presented objective model outcomes and identified the optimal solutions to expand airport capacity while minimizing overall costs. The results of this work indicated that the moderating effect of traffic uncertainties can make a difference with an optimal solution. Therefore, airport decision-makers and airport planners should carefully consider the uncertainty factors that would influence the airport capacity expansion solution. This research demonstrated the effectiveness of combining MINLP and the Monte Carlo simulation to support a long-term strategic decision for airport capacity problems in metropolitan areas at the early stages of the planning process while addressing future traffic demand uncertainty. Other uncertainty factors, such as political events, new technologies, alternative modes of transport, financial crisis, technological innovation, and demographic changes might also be treated as uncontrollable variables to augment this optimization model

Optimisation of automatic train protection systems.

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Urban Public Transport Futures: Broadening the Policy Debate

The Fourth International Conference on Competition and Ownership in Land Passenger Transporti, held 10-12 July 1995 in Rotorua, New Zealand, provided a forum for presentation and debate on the latest developments in the provision of land-based public transport. Over 120 participants from around the world gathered over 4 days in 5 workshops and 3 plenary sessions. The workshops were 1: Competitive models and impacts, 2: User requirements, 3. Rail sector issues, 4: Regulatory reform and transport policy development, and 5: International experiences in competitive operationsii. The opening address and workshop reports presented herein enable a wider audience to benefit from the outcomes of the deliberations

Efficiency in rail systems through three different approaches and contributions to push the Brazilian rail system toward high performance

Tese (Doutorado em Administração) - Universidade Federal do Rio de Janeiro, Rio de Janeiro, 2019Inclui bibliografiaThis research investigates the efficiency of the Brazilian rail cargo system (SFBC, acronym in Portuguese). The importance of the performance of a rail system to the logistics of goods in countries with large territorial dimensions is recognized. However, its role is secondary in Brazil compared to road transport, representing high economic and environmental costs. SFBC is dedicated to the export of mineral and agricultural bulk where it has a significant capacity for insertion. Meanwhile, the SFBC has an insignificant participation in the internal distribution of goods, which is mostly done in highways, including on longer routes. Consequently, the transport sector in Brazil emits twice as much CO2 from buming fuels than the world average. SFBC presents characteristics of a medium performance scenario. The performance of the operators is heterogeneous, benchmarking is an outlier, the average efficiency is low, and the average idleness of the sections is high. To discuss the conditions to achieve a high performance scenario is the main contribution of this thesis. Three researches were done to address this issue. The first one is dedicated to estimate the efficiency of the railway concessionaires in Brazil between 2010-2014 by using Data Envelopment Analysis. In a second stage, the significance of selected variables was assessed through Bootstrap Truncated Regression, including the type of the use of the railway track (shared or monopoly), a gap in the literature. The operators were grouped according to the efficiency scores and the type of returns to scale, and measures to increase the efficiency of the clusters were discussed. The second research has the purpose to explain the heterogeneity found in the average efficiency of the different railway systems in the world, the object of researches done between 2000-2016, through a meta-analysis carried out for the first time onj railways. For greater robustness, Leave-One-Out-Cross-Validation and VVeighted Regression were applied. Public policies induding diversification of services and models for assessing efficiency by regulatory agencies were discussed. The third research is devoted to the efficiency of the SFBC raílway sections and identifies the significant conditions for high and low performance scenarios by combining the Technique for Order of Preference by Similarity to Ideal Solution and a differential evolution algorithm for estimating the weights of variables in optimized scenarios, another gap in the literature. In a second stage, the significance of the variables selected was evaluated. The research shows that the public manager should push the rail companies toward the transportation of any type of cargo, the diversification of services, the centralized control of the operation, and the sharing of the railway track. The competition and diversifìcation are significant for high performance.A pesquisa investiga a eficiência do Sistema Ferroviário Brasileiro de Cargas (SFBC). É reconhecida a importância do desempenho de um sistema ferroviário para a logística de mercadorias em países de grandes dimensões territoriais. Todavia, seu papel é secundário no Brasil frente ao transporte rodoviário, representando custos econômicos e ambientais excedentes. O SFBC se mantém dedicado à exportação de granéis sólidos minerais e agrícolas onde apresenta significativa capacidade de inserção, enquanto é inexpressiva sua participação na distribuição interna de bens, majoritariamente realizada pelo setor rodoviário, inclusive em rotas mais longas. Assim, o setor de transporte no Brasil emite o dobro de CO2 pela queima de combustíveis do que a média mundial. O SFBC apresenta características de um cenário de média performance. O desempenho dos operadores é heterogêneo, o benchmarking é um outlier, a eficiência média é baixa e a ociosidade média das seções é alta. Discutir as condições para alcançar um cenário de alta performance é a principal contribuição da tese. Para atingir esse objetivo, foram realizadas três pesquisas. A primeira se dedica à eficiência dos concessionários ferroviários no Brasil no período 2010-2014, com o uso de Data Envelopment Analysis. Num segundo estágio, através de Bootstrap Truncated Regression, foi avaliada a significância de variáveis selecionadas, incluindo o tipo de uso da via, gap da literatura. Os operadores foram agrupados segundo os resultados de eficiência e o tipo de retornos de escala das operações e medidas para o aumento da eficiência dos clusters foram discutidas. A segunda pesquisa tem por objetivo explicar a heterogeneidade encontrada na eficiência média de diversos sistemas ferroviários no mundo, objeto de pesquisas realizadas entre 2000-2016, através de uma metanálise conduzida pela primeira vez em ferrovias. Para maior robutez, Leave-One-Out-Cross-Validation e Weighted Regression foram utilizadas. Políticas públicas incluindo diversificação e modelos de avaliação de eficiência por órgãos reguladores foram comentadas. A terceira pesquisa se dedica à eficiência das seções ferroviárias e identifica as condições significativas para cenários de alta e baixa performance através da combinação de Technique for Order of Preference by Similarity to Ideal Solution e de um algoritmo de evolução diferencial para estimar os pesos de variáveis em cenários otimizados, gap da literatura. Num segundo estágio, a significância de variáveis selecionadas foi avaliada. A pesquisa mostra que o gestor público deve empurrar as empresas para o transporte de todo o tipo de carga, a diversificação de serviços, o controle centralizado da operação e o compartilhamento da via. A competição e a diversificação são significativas para a alta performance

Catalog of selected heavy duty transport energy management models

A catalog of energy management models for heavy duty transport systems powered by diesel engines is presented. The catalog results from a literature survey, supplemented by telephone interviews and mailed questionnaires to discover the major computer models currently used in the transportation industry in the following categories: heavy duty transport systems, which consist of highway (vehicle simulation), marine (ship simulation), rail (locomotive simulation), and pipeline (pumping station simulation); and heavy duty diesel engines, which involve models that match the intake/exhaust system to the engine, fuel efficiency, emissions, combustion chamber shape, fuel injection system, heat transfer, intake/exhaust system, operating performance, and waste heat utilization devices, i.e., turbocharger, bottoming cycle

Railway Research

This book focuses on selected research problems of contemporary railways. The first chapter is devoted to the prediction of railways development in the nearest future. The second chapter discusses safety and security problems in general, precisely from the system point of view. In the third chapter, both the general approach and a particular case study of a critical incident with regard to railway safety are presented. In the fourth chapter, the question of railway infrastructure studies is presented, which is devoted to track superstructure. In the fifth chapter, the modern system for the technical condition monitoring of railway tracks is discussed. The compact on-board sensing device is presented. The last chapter focuses on modeling railway vehicle dynamics using numerical simulation, where the dynamical models are exploited

Physical distribution in South Africa : a review and a system design for hanging textile merchandise

Bibliography: pages 149-150.The subject of physical distribution was first examined in the early 1900s. It was developed and refined especially during World II under the name of 'Logistics', and began to be adopted in the field of business from the 1950s. From the 1960s onwards, national bodies have been established, both in the U.S. and the U.K., and works and theories have been published leading to the establishment of journals and the establishment of formal education programmes all dealing with physical distribution. A review of published works on the subject was undertaken. Some books were studied, as well as a number of journal articles dating from the early 1970s. No suitable references were obtained dealing with the subject in a South African context. A project was also carried out to design a system for distributing garments in a hanging mode. The thesis thus concerns a general review of physical distribution management and the distribution of goods and services throughout business and industry, with an emphasis being placed on south African conditions. The principal objectives of this study were to examine and review the state-of-the-art of the general theory and the use of physical distribution, to suggest means of applying it in South Africa and to briefly examine future trends and developments. These objectives were achieved by examining from books and articles the concept and theory of distribution, its interrelationships with aspects such as marketing, production and business organisations, and its management in business organisations: by discussing some characteristics of South African business and industry; by examining certain areas that provide the greatest potential for improvements: by discussing a project carried out to design a distribution system for hanging garments merchandise; and by examining future trends both overseas and in South Africa. Physical distribution is shown to be an important subject for business and society and for the economy as a whole. It is always changing in a dynamic environment and requires constant monitoring. This thesis shows how this field, which has been researched and developed overseas, is affected by local conditions and should be applied to specific areas in South Africa