Online public deliberation for a regional transportation improvement decision

This paper investigates the potential for deliberation as a means for public participation in shaping public policy. The paper begins with a summary of deliberative democracy and other concepts that recently have motivated an interest for online deliberation. Next, the paper describes a case study in which 133 public participants deliberated over a regional transportation improvement decision. The deliberation occurred entirely over the internet and lasted for 31 days. The participants wrote hundreds of posts (comments) and made thousands of post-ratings (statements of agreement or disagreement). The posts and three questionnaires are analyzed quantitatively and qualitatively to assess the nature of the deliberation and the participants’ perception of their experience. A negative binomial regression is used to examine which participant characteristics are associated with writing more posts.     

Biological effects of Mississippi River nitrogen on the northern gulf of Mexico—a review and synthesis

The Mississippi River currently delivers approximately 1.82 Tg N year⁻¹ (1.3×10¹¹ mol N year⁻¹) to the northern Gulf of Mexico. This large input dominates the biological processes of the region. The “new” nitrogen from the river stimulates high levels of phytoplankton production which in turn support high rates of bacterial production, protozoan and metazoan grazing, and fisheries production. A portion of the particulate organic matter produced in the pelagic food web sinks out of the euphotic zone where it contributes to high rates of oxygen consumption in the bottom waters of the inner shelf, resulting in the development of an extensive zone of hypoxia each summer. In spite of the significance of this river system to the coastal ocean of the northern gulf, we do not have an adequate understanding of the inputs, processing and ultimate fates of river nitrogen. Here we review available literature on this important system and propose a conceptual model showing how biological processes evolve in the river plume between the point of discharge and the point where plume waters are fully diluted by mixing with oceanic water.     

Effects of waste disposal on benthic faunal succession on the abyssal seafloor

Strategies to predict, and thus limit, potentially detrimental environmental impacts of abyssal disposal of wastes are severely limited by our lack of knowledge of deep-sea processes and lack of opportunity to directly study waste disposal in abyssal environments. Probable successional sequences following burial of benthic faunas by sewage sludge and dredged material on the abyssal seafloor are drawn by analogy with well-known processes in shallow-marine water. Scales of change and recovery of abyssal benthic faunas from episodic deposition of waste material are examined by extrapolation from what is currently known about turbidite sedimentary provinces, in particular, the Venezuela Abyssal Plain and the Great Meteor East area of the Madeira Abyssal Plain. Results suggest that initial benthic faunal recolonization would take place within years following episodic depositions of waste on the abyssal seafloor. Anoxic conditions or chemical inhibitory effects may delay initial benthic recolonization for hundreds of years. Establishment of equilibrium benthic faunal assemblages probably takes hundreds to potentially thousands of years. Potentially detrimental effects dictate that the surface areas of individual waste deposits should be minimized and the deposits should be isolated by capping with nontoxic materials or chemical barriers.     

Port state control versus marine environmental pollution

This work analyses whether port state control (PSC) has been effective in reducing environmental pollution in the region it covers. The analysis covers the technical and political aspects of PSC's effectiveness. To match the complexity of marine environmental pollution and safety issues, several indicators are developed to assess performance under both aspects. Previous studies on quantitative and qualitative material, as well as fresh evidence, are utilized to obtain quantitative or qualitative evaluations, as the case may be. The separate insights are then combined to reach an integrated conclusion. PSC is found to be effective in fighting marine environmental pollution, but with peripheral shortcomings of a mainly operational nature. These shortcomings limit the effectiveness to a less than optimal degree.     

Interaction Dynamics Between an Electric Vehicle's 'Pantograph' and the Road

In this paper, we briefly describe the patented E-TRAN electric roadway & vehicle concept and then proceed to study the dynamic effects of an associated road pantograph in contact with a road mounted power strip. During usage, the road pantograph (supported underneath the vehicle) allows power to be drawn from the strip for powering the motor driven vehicle. From a mechanical point of view, friction, wear and dynamic bounce effects impact the reliability arid maintainability of the pantograph/strip concept. To study bounce effects, a dynamic model of a one degree of freedom road pantograph was developed for both contact and noncontact situations. These dynamic “bounce” effects were simulated using a MATRIXx™ based model of the road pantograph and associated road surface (and strip). In order to do so, several simulation issues had to be addressed (some of which may be of interest to those studying wheel/rail contact effects). To corroborate the dynamic model, an instrumented experimental pantograph/road simulator was fabricated. Reasonable correspondence was achieved between the experimentally measured and simulated support forces and pantograph angle. Parametric variations in the design were also studied through simulation. The work presented serves as a paradigm for designing, building, and testing road pantographs for specific applications.     

Bicycle commuting in Melbourne during the 2000s energy crisis: A semiparametric analysis of intraday volumes

Cycling is attracting renewed attention as a mode of transport in western urban environments, yet the determinants of usage are poorly understood. In this paper we investigate some of these using intraday bicycle volumes collected via induction loops located at ten bike paths in the city of Melbourne, Australia, between December 2005 and June 2008. The data are hourly counts at each location, with temporal and spatial disaggregation allowing for the impact of meteorology to be measured accurately for the first time. Moreover, during this period petrol prices varied dramatically and the data also provide a unique opportunity to assess the cross-price elasticity of demand for cycling. Over-dispersed Poisson regression models are used to model volumes at each location and at each hour of the day. Seasonality and the impact of weather conditions are modelled as semiparametric and estimated using recently developed multivariate penalized spline methodology. Unlike previous studies that use aggregate data, the empirical results show a substantial meteorological and seasonal component to usage. They also suggest there was substitution into cycling as a mode of transport in response to increases in petrol prices, particularly during peak commuting periods and by commuters originating in wealthy and inner city neighbourhoods. Last, we extend the approach to a multivariate longitudinal count data model using a Gaussian copula estimated by Bayesian data augmentation. We find first order serial dependence in the hourly volumes and a ‘return trip’ effect in daily bicycle commutes.     

Ship complexity assessment at the concept design stage

An innovative complexity metric is introduced that provides a way to compare similar or different ship types and sizes at the contract design stage. The goal is to provide the designer with this information throughout the design process so that an efficient design is obtained during the first design run. Application to and validation on real passenger ships indicate that there is a significant correlation between the error in an engineer’s judgement of complexity and the cost assessment error. It follows that this tool could be used to improve knowledge of the ship’s complexity at the contract design stage, and even to try to optimise the design if the complexity criteria are not fixed by the shipowners.