Revisiting urban hierarchy and specialization from a maritime perspective

ABSTRACT

Port–city relationships have attracted paramount attention from a variety of scientific disciplines for several decades, such as geography, history, planning, regional science, sociology, and economics to name but a few. Yet, the extent to which maritime traffic specialization obeys the same spatial distribution than other economic activities remains underexplored today. This article tackles these lacunae head-on by proposing an empirical analysis of the way vessel tonnage per main categories of flows (e.g. containers, bulks, passengers) coincides with the demographic size of the world’s coastal and inland city-regions, using novel data on global inter-port vessel movements and harmonized population data over the period 1977–2008. Our main results confirm that such traffic is far from being randomly distributed, as its volume, value, and diversity concentrate at the top of the urban hierarchy. This research motivates the need to further integrate physical connectivity into the study of cities and their development mechanisms.     

Observability in traffic networks. Plate scanning added by counting information

The paper deals with the observability problem in traffic networks, including route, origin?Cdestination and link flows, based on number plate scanning and link flow observations. A revision of the main observability concepts and methods is done using a small network. Starting with the full observability of the network based only on number plate scanning on some links, the number of scanned links is reduced and replaced by counted link flows, but keeping the full observability of all flows in the network. In this way, the cost can be substantially reduced. To this end, several methods are given and discussed, and two small and one real case of networks are used to illustrate the proposed methodologies. Finally, some conclusions and final recommendations are included.     

Renegotiating PPP Contracts: Reinforcing the ‘P' in Partnership

Abstract

The issue of renegotiation is becoming increasingly important as a tool to address uncertainty of public private partnership (PPP) projects and as a mechanism to restore its economic and financial equilibrium. This paper aims to understand how and why renegotiations occur in long-lasting PPP projects and what are the pros and cons of the renegotiation. We depart from a literature review on contract incompleteness and on the determinant factors for the renegotiation of infrastructure concessions. To illustrate the discussion, the case studies of nine European PPP projects are analysed by examining the specific exogenous and endogenous determinant factors that conduce to renegotiating contracts. The implications of contractual renegotiations are explained and summarized through a comparison of our case studies with literature. Although renegotiation, per se, is not a solution for the successful implementation of PPP projects, our findings reinforce the idea of contractual flexibility as a tool that allows adapting to uncertainty. Moreover, effective communication mechanisms allow a better response to unforeseen events, reinforcing the partners’ commitment to deliver a win–win project.     

Modelling passengers,buses and stops in traffic microsimulation: review and extensions

In the last decade, significant research efforts and technology have been dedicated to the development of microsimulation tools for a better representation of traffic systems. As a result, several commercial packages appeared and they are used nowadays in the detailed modelling of different transportation systems and operations for specific project evaluations and local designs, mostly within the urban context. After reviewing the specialized literature, we realized that most of these microsimulation tools are oriented to the movement of cars, leaving the public transportation systems as a complement, just for a realistic representation of the transportation system as a whole, but always oriented to simulate cars. In this paper, the objective is to provide guidelines on how to incorporate the necessary entities and components for a proper simulation of public transport systems in a microsimulation environment. Thus, the different approaches to simulate transit systems at a microlevel are discussed, highlighting the necessity of including stops, passengers and transit vehicles explicitly as entities within the microsimulation environment, for modelling transfer operations, control strategies, etc. Several examples are then provided to quantify the impact of such representations, for different cases and potential simulation platforms. Copyright © 2010 John Wiley & Sons, Ltd.     

The impact of the Panama Canal expansion on Panama’s maritime cluster

The Panama Canal is currently in the process of a major expansion effort. After the new set of locks is opened in 2016, significantly larger ships can traverse the Canal. The current lock system has been in place for over 100 years, even though the size of ocean-going vessels has expanded considerably. One impact is on Panama’s maritime cluster. It is expected that the expansion will result in greater demand for many of the goods and services provided by the cluster. This article examines the economic impact of the Canal expansion on Panama’s maritime cluster. Clusters of economic activity can result in economies of agglomeration and supply chain network effects. Without these economies and network effects, clusters would not have a competitive advantage over businesses that are not in a cluster. It is expected that with a larger cluster, both agglomerative economies and network effects will increase. But, which cluster components will grow and which will not be affected to a great extent? To what extent will bottlenecks appear? These are some of the questions that this article addresses.     

The polarization of global container flows by interoceanic canals: geographic coverage and network vulnerability

It is widely acknowledged that the two major interoceanic canals of Suez and Panama play a central role in global shipping flows. However, this role has rarely been measured with precision both in terms of the geographic coverage and network topological properties of canal-dependent flows. Based on vessel movement data for containerships, this research clarifies the weight and share of canal-dependent flows globally and at the level of world regions, routes, and ports. It also estimates and maps the effects of removing canal-dependent flows from the network by means of graph-theoretical methods. While main results converge in showing a decreasing importance of canal shipping in the context of growing south-south trade exchanges, certain areas remain more dependent than others, such as Asia, Europe, and North America. The research also underlines factors of port vulnerability across the globe in relation with the two canals.     

Shipping Lines and Logistics

Abstract

It has been acknowledged that logistics is a driving force that shapes the integration of the transport chain. This paper argues that while the liner shipping industry exhibits increased horizontal integration, its vertical integration remains limited. A clear distinction is drawn between freight logistics, container logistics and vessel logistics. Freight logistics is defined as part of the supply chain process, the focus of which is the goods being transported. The purpose of container logistics is to optimize the movements of the containers themselves, an operation that is directly related to vessel logistics which is concerned with maximizing vessel utilization. The paper demonstrates that shipping lines have to find the correct balance between these three types of logistics. Their interest in vertical integration is primarily because the management of container logistics provides direct support to vessel logistics. Their involvement in freight logistics remains unclear and uncertain.     

A slacks-based network DEA efficiency analysis of European airlines

Conventional data envelopment analysis (DEA) models consider a system as a single-process ‘black box’. There are, however, DEA approaches that consider a system as composed of distinct processes or stages, each one with its own inputs and outputs and with intermediate flows among the stages. In this paper, a network DEA approach to airline efficiency assessment is presented. One conclusion of the study is that the network DEA approach has more discriminative power than the single-process DEA approach and that the computed targets, efficiency scores and rankings are more valid. This is because network DEA allows for a more fine-grained analysis that leads to a more realistic estimation of the overall system production possibility set than the one assumed by conventional DEA. In other words, compared with network DEA the conventional, single-process DEA represents an aggregated analysis that merges all system processes with their inputs and outputs and ignores their internal flows. The main drawbacks are the need for more detailed data (i.e. at the process level) and the greater complexity of the resulting models, especially if there are inputs or outputs that are shared among the processes.     

The urban road pricing scheme to curb pollution in Milan,Italy: Description,impacts and preliminary cost–benefit analysis assessment

Starting from January 2008 Milan implemented a charging scheme to enter an 8 km² area of the city centre. The term used to denote the scheme is Ecopass, conveying the stated political objective of the scheme: a pass to improve the quality of the urban environment (ECO). The charge depends on the Euro emission standard of the vehicle. The paper illustrates the main features and impacts of the Milan Ecopass scheme, and presents a preliminary cost–benefit analysis. The scheme has been effective in curbing not only pollution emissions, but also congestion, and the result has been achieved with low implementation costs and without major political opposition. The cost–benefits analysis presents an overall net benefit. The identification of the winners and losers of the policy is conditioned by penalty payments. Without including the penalties, the surface public transport users and the society at large are the main winners, whereas car and especially freight vehicle users are net losers.     

The new governance structure of French seaports: an initial post-evaluation

France undertook a large port reform in 2008, which came into force in 2010–2011. It mostly applies a landlord port model to major French seaports, with the prediction that doing so will restore competiveness. This article presents the 2008 port reform, discusses why it was needed, notably with regard to the underperformance of container traffic, and details how new governing bodies are sharing their responsibilities amongst themselves. To this end, a textual analysis of the agenda items for the governing bodies created since 2011 of the largest French seaport, Port of Marseille, provides a means to compare the items discussed by the former management bodies. This analysis identifies a trend, in which the supervisory board focuses on global issues, the advisory board addresses local issues, and the board of directors considers internal issues. Even if ongoing, this transition creates favorable conditions to work more efficiently and may represent a step toward the better performance of French seaports.