On modeling telecommuting behavior: option, choice, and frequency

The current study contributes to the already substantial scholarly literature on telecommuting by estimating a joint model of three dimensions—option, choice and frequency of telecommuting. In doing so, we focus on workers who are not self-employed workers and who have a primary work place that is outside their homes. The unique methodological features of this study include the use of a general and flexible generalized hurdle count model to analyze the precise count of telecommuting days per month, and the formulation and estimation of a model system that embeds the count model within a larger multivariate choice framework. The unique substantive aspects of this study include the consideration of the “option to telecommute” dimension and the consideration of a host of residential neighborhood built environment variables. The 2009 NHTS data is used for the analysis, and allows us to develop a current perspective of the process driving telecommuting decisions. This data set is supplemented with a built environment data base to capture the effects of demographic, work-related, and built environment measures on the telecommuting-related dimensions. In addition to providing important insights for policy analysis, the results in this paper indicate that ignoring the “option” dimension of telecommuting can, and generally will, lead to incorrect conclusions regarding the behavioral processes governing telecommuting decisions. The empirical results have implications for transportation planning analysis as well as for the worker recruitment/retention and productivity literature.     

A household-level activity pattern generation model with an application for Southern California

This paper develops and estimates a multiple discrete continuous extreme value model of household activity generation that jointly predicts the activity participation decisions of all individuals in a household by activity purpose and the precise combination of individuals participating. The model is estimated on a sample obtained from the post census regional household travel survey conducted by the South California Association of Governments in the year 2000. A host of household, individual, and residential neighborhood accessibility measures are used as explanatory variables. The results reveal that, in addition to household and individual demographics, the built environment of the home zone also impacts the activity participation levels and durations of households. A validation exercise is undertaken to evaluate the ability of the proposed model to predict participation levels and durations. In addition to providing richness in behavioral detail, the model can be easily embedded in an activity-based microsimulation framework and is computationally efficient as it obviates the need for several hierarchical sub-models typically used in extant activity-based systems to generate activity patterns.     

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.     

Congestion pricing for Latin America: Prospects and constraints

In an effort to reduce the adverse impacts of the car and promote sustainable transport in Latin America, some governments have either implemented travel demand management policies or have considered ways of directly reducing the number of vehicles in congested areas. While demand management measures have been promoted in a small number of countries, including vehicular restrictions as well as the promotion of public transport modes, there are currently no congestion pricing programmes in operation in Latin America. This paper begins with an overview of travel demand management, including its principal aims as well as its primary objectives within the Latin American context. It discusses past efforts to promote traffic restraint and perspectives for developing congestion pricing schemes in both São Paulo and Santiago. Finally, it examines the potential role of congestion pricing as a demand management tool. While it is one of the most effective demand management measures in the industrialised world, a number of barriers currently prevent it from being widely adopted in Latin America.     

Surveillance and Poaching on Inshore Reefs of the Great Barrier Reef Marine Park

The Great Barrier Reef (GBR), Australia, is managed under the GBR Marine Park Act (1975) and is seen as a shining example of marine resource management. The principle tool of management is zoning for multiple use. We examined surveillance and illegal fishing around two inshore islands (Magnetic and Orpheus) of the GBR Marine Park in 2000/2001. Both islands are near Townsville, the largest city adjacent to the GBR. Surveillance effort was low, with vessels present on only 16% of days of the year. Measurable but low levels of illegal recreational fishing occurred within no-take zones. Levels decreased with increasing surveillance effort. Thus zoning was not completely successful in protecting fish targeted by fisheries, even within the most highly enforced sections of the Park. The expansion of no-take zones in 2004 from 4.6% to 33.4% of the area of the 358,000 km2 Park represents a considerable challenge for future surveillance and enforcement.     

A game-theoretical approach for modeling competitions in a maritime supply chain

ABSTRACT

To accommodate the structural changes in logistics, competitions along a maritime supply chain are more intensive than before. This paper adopts a two-stage noncooperative game-theoretical approach to model the horizontal and vertical interactions among liners and ports. In the first stage, Bertrand game is applied to model the interactions between two liners. When the shipping line decides which port to call, a multinomial Logit model is applied. In the second stage, Bertrand game is applied to model the competitions between two ports. Nash equilibrium is derived by solving the Bertrand games. A numerical example is provided as a case study.     

Integrating Climate and Ocean Change Vulnerability into Conservation Planning

Tropical coastal and marine ecosystems are particularly vulnerable to ocean warming, ocean acidification, and sea-level rise. Yet these projected climate and ocean change impacts are rarely considered in conservation planning due to the lack of guidance on how existing climate and ocean change models, tools, and data can be applied. Here, we address this gap by describing how conservation planning can use available tools and data for assessing the vulnerability of tropical marine ecosystems to key climate threats. Additionally, we identify limitations of existing tools and provide recommendations for future research to improve integration of climate and ocean change information and conservation planning. Such information is critical for developing a conservation response that adequately protects these ecosystems and dependent coastal communities in the face of climate and ocean change.     

Climate change projections for variables affecting road networks in Europe

Global climate change will affect road networks during this century. The effects will be different in various parts of the world due to differences in local climate change and in the structure and properties of roads. In this paper, climate change projections are presented for climate variables that are most likely to affect the long-term performance of road networks in Europe. We apply four regional climate simulations up to the year 2100 using two plausible future emission scenarios. The results show that the changing climate will require significant adaptation measures in the near future in order to maintain the operability of the European road network.     

Establishing speed–flow–density relationships for exclusive motorcycle lanes

Abstract

The motorcycle is a popular mode of transport in Malaysia and developing Asian countries, but its significant representation in the traffic mix results in high rates of motorcycle accidents. As a result, the Malaysian Government decided to segregate motorcycle traffic along its new federal roads as an engineering approach to reduce accidents. However, traffic engineers needed to know the maximum traffic a motorcycle lane could accommodate. Despite substantial literature related to speed–flow–density relationships and capacities of various transport facilities, there is a knowledge gap regarding motorcycle lanes. This paper establishes motorcycle speed–flow–density relationships and capacities of exclusive motorcycle lanes in Malaysia. Observations of motorcycle flows and speeds were conducted along existing and experimental motorcycle lanes. Motorcycle speed–density data were aggregated and plotted for two types of observable motorcycle riding behaviour patterns that were influenced by the widths of a motorcycle lane: the headway pattern (lane width ≤ 1.7 m) and the space pattern (lane width > 1.7 m). For both riding patterns, regression analysis of motorcycle speed–density data best fits the logarithmic model and consequently the motorcycle flow–density and speed–flow models are derived. Motorcycle lane capacities for headway and space riding patterns are estimated as 3300 mc/hr/lane and 2200 mc/hr/m, respectively.