Analysis of the effectiveness of control measures to mitigate road dust emissions in a regional network

The effectiveness of control measures to reduce road dust emissions is analyzed using a year’s data of road dust emissions collected with a mobile sampling platform and a survey of road maintenance practices in the Lake Tahoe Basin of Nevada and California US. Attributes such as sweeping practices, anti-icing, shoulder improvement, pavement condition, trackout, and abrasive material from road segments were analyzed with a feature subset selection algorithm. Street sweeping was found to be an effective means of controlling dust emissions from roads. Road dust from dirty tertiary roads served as a continuous source of suspendable material for adjacent high-speed roads in the winter time. To be most effective, emission control strategies require that not only primary roads, but all roads be swept after snow storms to recover applied abrasive material.     

Are travelers substituting between transportation network companies (TNC) and public buses? A case study in Pittsburgh

Transportation - Transportation network companies (TNC) provide mobility services that are influencing travel behavior in unknown ways due to limited TNC trip-level data. How they interact with...     

Airport obstacle surfaces

The most commonly used criteria to determine complicated airport obstacle surfaces are FAR Part 77 imaginary surfaces, TERPS, and the one engine inoperative obstacle identification surface for air carriers. For each obstacle surface there are tradeoffs encountered in our practice between the obstruction penetration and extension of runway, change of flight profile, and allowable aircraft maximum payloads. For the purposes of both airport engineering and airport planning, a better understanding of these different obstacle surfaces and their application is important. In this paper, the differences and relationships between these surfaces are addressed. The conditions for the use of each criterion are discussed. In addition, the FAA's Obstruction Evaluation / Airport Airspace Analysis (OE/AAA) process is reviewed.     

Discriminatory attitudes between ridesharing passengers

Transportation - Prior studies have provided evidence of discrimination between drivers and passengers in the context of ridehailing. This paper extends prior research by investigating...     

The Value of a Spillover Fishery for Spiny Lobsters Around a Marine Reserve in Northern New Zealand

The contribution that Leigh Marine Reserve in northern New Zealand makes to the local spiny lobster fishery was examined by comparing the catch characteristics of Jasus edwardsii around the reserve boundary with those from Coastal Leigh, 0.3-2 km from the reserve, and Little Barrier Island, 22-30 km from the reserve. Seasonal trends were apparent in the reserve catch characteristics, consistent with lobster movements into and out of offshore fishing areas adjacent to the boundary. No significant difference was detected in catch per unit effort (kg.trap haul -1 ) among locations. However, the catch around the marine reserve consisted of fewer but larger lobsters than at Little Barrier Island, while the size and number of lobsters caught per trap haul at Coastal Leigh was intermediate between the other two locations. Catch rates around the reserve were more variable than at the other sites, but on average, the amount of money made per trap haul was similar to Little Barrier Island and Coastal Leigh.     

Development of a Human Use Objectives Framework for Integrated Management of the Eastern Scotian Shelf

Under the 1997 Oceans Act, Fisheries and Oceans Canada (DFO) is required to lead and facilitate the development of integrated management plans for Canada's oceans. One of the integrated management projects is the Eastern Scotian Shelf Integrated Management Initiative (ESSIM), through which DFO is working with a range of stakeholders to develop and implement an integrated ocean management plan for the eastern Scotian Shelf. As part of this Initiative, DFO has undertaken a program to develop a set of objectives and related indicators for ocean management. This includes the development of a framework, objectives, and indicators for human use of the resource including the social, economic, and institutional (governance) components of ocean management, areas that have received little attention internationally. This article provides some background to ESSIM and human uses of the resources of the eastern Scotian Shelf; briefly reviews objectives-based management and human use objectives internationally; outlines the process undertaken to develop the Human Use Objectives Framework; presents the resultant objectives and indicators that were developed; and highlights some of the lessons learned and challenges for their implementation.