Under which conditions is carrier cooperation possible? A case study in a Seville marketplace

The high volume of traffic originates two well-known problems in many cities: congestion and pollution. In recent years, a social phenomenon is emerging cooperation. This work is aimed at evaluating the circumstances under which transport cooperation is possible between different stakeholders operating in the same geographical area. To this end, a double survey process was conducted in a marketplace situated in the Seville City (Spain) centre. The first survey was designed to know the characteristics of the retailers and their preferences with respect to cooperation and regulations. A relational analysis between retailer features and their willingness to cooperate was carried out. After analysing the motivations for non-cooperation, a mixed proposal was designed and surveyed. Although the research was limited to a marketplace, the relevant data gathered from this double survey process highlights some implications: (a) the importance of personal relations in retailer cooperation; (b) a high volume of freight and the use of vans as on-street warehouses appear as significant motivations for non-cooperation; (c) forcing changes in the statu quo encourages cooperation.Ministerio de Economía y Competitividad (España) TEC2013-47286-C3-3-

A viral system to optimise the daily drayage problem

The intermodal transport chain can become more efficient by means of a good organisation of the drayage movements. Drayage in intermodal container terminals involves the pick up or delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. This paper focuses on a new approach to tackle the daily drayage problem by the use of viral system (VS). VS is a novel bio-inspired approach that makes use of a virus-infection biological analogy that is producing very satisfactory results when dealing with complex problems with huge feasibility region.Unión Europea TEC2013-47286-C3-3-

A satellite navigation system to improve the management of intermodal drayage

The intermodal transport chain can become more efficient by means of a good organization of the drayage movements. Drayage in intermodal container terminals involves the pick up or delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. The literature shows some works on centralised drayage management, but most of them consider the problem only from a static and deterministic perspective, whereas the work we present here incorporates the knowledge of the real-time position of the vehicles, which permanently enables the planner to reassign tasks in case the problem conditions change. This exact knowledge of position of the vehicles is possible thanks to a geographic positioning system by satellite (GPS, Galileo, Glonass), and the results show that this additional data can be used to dynamically improve the solution

Mejoras en el transporte intermodal: optimización en tiempo real del acarreo terrestre.

Tesis descargada desde TESEOEl transporte por carretera ha sido líder en el movimiento de mercancías. Sin embargo, el incremento de la congestión y la necesidad de buscar modos más sostenibles ha animado a las diferentes instituciones a promover la intermodalidad como alternativa; que combina la eficiencia del transporte ferroviario o marítimo con la flexibilidad del transporte por carretera. Sin embargo, el transporte intermodal presenta varias dificultades para llegar a ser viable. Uno de ellos es un alto coste fijo, que hace a la intermodalidad ineficiente en trayectos cortos, por debajo de una distancia umbral. En la cadena intermodal, los trayectos iniciales y finales realizados por carretera son llamados acarreo terrestre, y representan el 40 % de los costes totales. La adecuada planificación del acarreo presenta un gran potencial para reducir los costes intermodales y reducir la distancia a partir de la cual la intermodalidad es rentable; el principal objetivo es la asignación de tareas de transporte a vehículos, a veces en presencia de restricciones temporales. Esta asignación ha sido tradicionalmente realizada una vez al comienzo del día, de modo que ante cualquier suceso inesperado podrían producirse retrasos. Esta tesis propone el uso de información en tiempo real relativa a la posición de los vehículos para una solución dinámica del problema, donde el planificador está siempre habilitado a rehacer la programación en el caso de que las condiciones cambien. Este conocimiento de la posición de los vehículos es posible gracias al uso de sistemas de posicionamiento por satélite. Los resultados demuestran que esta información permite mejorar la solución dinámicamente.Road transport has always been prevalent in the movement of freight. However, the increasing road congestion and the necessity to find more sustainable means of transport have encouraged different governments to promote intermodality as an alternative. This combines the cost effectiveness of railways or ships with the flexibility of trucks. However, intermodal transport has several difficulties to overcome in order to become viable. One of them is a high fixed cost, which is why intermodality is unsuitable for trips shorter than a certain threshold distance. In an intermodal transport chain, the initial and final trips, also called drayage operations, represent 40 % of total transport costs. The proper planning of drayage operations has the potential to reduce the threshold distance, thus it raises the viability of intermodal transport. The intermodal transport chain can become more efficient by means of a good organization of drayage movements; the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. This scheduling has traditionally been done once a day and, under these conditions, any unexpected event could cause timetable delays. This thesis proposes to use the real-time knowledge about vehicle position to solve this problem, which permanently allows the planner to reassign tasks in case the problem conditions change. This exact knowledge of the position of the vehicles is possible due to the use of a geographic positioning system by satellite (GPS, Galileo, Glonass). The results show that these additional data can be used to dynamically improve the solution

Método de estimación de la puntualidad en redes ferroviarias a través de la función densidad de probabilidad de los retrasos primarios

La presente herramienta surgió por la necesidad de pronosticar el retraso de un tren de mercancías. Era necesario cuantificar la influencia que tiene en el tiempo de transito de un convoy los distintos servicios que operan simultáneamente en la red ferroviaria. Se explican los mecanismos de propagación de los retrasos, explicando la diferencia entre retrasos primarios y retrasos secundarios; se hace una extensa descripción de método, donde se explicarán los datos que deben conocer el mismo y las salidas que podrá proporcionar; describirán una serie de aplicaciones de la metodología seguida y se muestran una serie de conclusiones

Dynamic approach to solve the daily drayage problem with travel time uncertainty

The intermodal transport chain can become more e cient by means of a good organization of drayage movements. Drayage in intermodal container terminals involves the pick up and delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the di erent vehicles, often with the presence of time windows. This scheduling has traditionally been done once a day and, under these conditions, any unexpected event could cause timetable delays. We propose to use the real-time knowledge about vehicle position to solve this problem, which permanently allows the planner to reassign tasks in case the problem conditions change. This exact knowledge of the position of the vehicles is possible using a geographic positioning system by satellite (GPS, Galileo, Glonass), and the results show that this additional data can be used to dynamically improve the solution

How efficient is city logistics? Estimating ecological footprints for urban freight deliveries

Es una ponencia de The Sixth International Conference on City Logistics, en Puerto Vallarta, México http://toc.proceedings.com/18996webtoc.pdfIn medium and large cities, the delivery of goods represents a significant contribution to the problems of congestion, lack of parking, pollution and energy consumption. The characteristics of this type of transport are also very different from passenger mobility, even though they are often assimilated, due to the lack of specific tools for estimation and analysis, and also of indicators to evaluate improvements in the systems of urban goods distribution. In this work, we start by developing a systematic model to estimate the transport of goods in a city, according to the particularities of its supply and demand. This model can then be used to determine with a high level of detail the contribution of the delivery of goods to the ecological footprint of the city, thus proposed as the key indicator of the efficiency of this type of transport. The work is applied to the city of Seville, in Spain.Spanish Ministry of Science and Technology DPI2008-0647

Impacto del conocimiento en tiempo real de la posición de una flota de vehículos sobre la mejora de acarreo intermodal

Este artículo resuelve el problema del acarreo en una red con enlaces cuya duración es estocástica. Y pone de relieve la importancia del conocimiento en tiempo real de la posición exacta de los vehículos de la flota para llevar a cabo una correcta asignación de tareas a la misma. El modelo tiene un carácter dinámico al ser capaz de reasignar tareas a medida que se conocen datos con mayor certeza

Impacts of a Tracking and Tracing System for Containers in a Port-Based Supply Chain

Purpose - Intermodal transport chains often appear as “black boxes” to the cargo owners and their clients, who lose track of the container until it arrives at the final end of the chain. The paper discusses why a tracking and tracing system should represent an important added value for them. Design/methodology/approach - We describe here the configuration and features of a novel low-cost system to track and trace containers in an intermodal supply chain, provide information to shippers regarding delays and other unexpected events, and assist terminal operations accordingly. We then analyze the positive impacts of such a system over the entire supply chain, identifying the requirements of the main chain actors regarding the availability of information and how the proposed system contributes to the fulfillment of those requirements. Findings - The visibility of containers throughout the entire supply chain provides multiple benefits for shippers, terminals and transport providers. Research limitations/implications - The operational and economic benefits of the system are clear, but the lack of historical data does not allow for a quantitative estimation of those foreseen benefits. Practical implications - Intermodal terminals might see this type of information systems as an opportunity to generate added value for their customers, including shippers and carriers. In a scenario with high competition levels between terminals, this added value could represent the competitive advantage necessary to guarantee the growth of a terminal without requiring expensive investments and costs. Originality/value - The paper describes the benefits provided by the system to the main stakeholders of the intermodal supply chain and provides some conclusions with respect to those benefits and to future developments.Fundación de Investigación de la Universidad de Sevilla FIUS-2284Ministerio de Economía y Competitividad (España) TEC2013-47286-C3-3-