In North America, most rail corridors are constructed using ballasted track. Monitoring the ballast support condition and improving upon current sub-structure/ballast maintenance strategies will ensure safe railroad operations. However, it is inherently difficult to evaluate the pressure distribution at the sleeperballast interface. Researchers at University of Illinois at Urbana-Champaign (UIU...

As implementation of the Ballast Water Convention draws nearer a major challenge is the development of protocols which accurately assess compliance with the D-2 Standard. Many factors affect the accuracy of assessment: e.g. large volume of ballast water, the shape, size and number of ballast tanks and the heterogeneous distribution of organisms within tanks. These factors hinder efforts to obta...

Railway transition zones between open track and rigid structures such as bridges and culverts often experience differential movements due to abrupt changes in track stiffness and complicated dynamic loading effects. Such conditions commonly lead to track geometry issues, consequently increasing the magnitude of impact loads at these areas. This in turn leads to excessive degradation of ballast ...

The spread of nonindigenous species (NIS) in aquatic ecosystems provides an opportunity to develop new perspectives on the invasion process. In this paper we review existing invasion models, most of which were developed to describe invasions of terrestrial habitats, and propose an alternative that explores long-distance invasions mediated by discharge of contaminated ballast water by ships inbo...

Worldwide transfer and introduction of non-indigenous species in ballast water causes significant environmental and economic impact. One way to address this problem is to remove or inactivate organisms that are found in ballast water. In this study, 3 experiments were conducted in Puget Sound, Washington, USA, using a prototype ozone treatment system installed on a commercial oil tanker, the S/...

Ballast water is a dominant mechanism for the interoceanic and transoceanic dispersal of aquatic non-native species (ANS), but few studies have addressed ANS transfers via smaller scale vessel movements. We analyzed ballast water reporting records and ANS occurrence data from four US West Coast port systems to examine patterns of intra-coastal ballast water transfer, and assess how ballast tran...

—Introductions of non-indigenous species in ballast water are one of the greatest threats to freshwater and marine ecosystems worldwide. New approaches to reducing the release of organisms from ballast water are under consideration nationally and internationally. Unfortunately, the development of scientifically defensible policy for controlling introductions from ballast water has been retarded...

This paper presents electronic ballast with dimming capability supplying a 32 W fluorescent lamp. The electronic ballast is a self-oscillating driving circuit with an additional circuit responsible for dimming the fluorescent lamp based on a signal from a lighting dependent resistor. This luminous sensor measures the luminous flux level and set the lamp power by the voltage gain variation of th...

The results of the ship ballast water treatment systems neutralization need to be verified in a transparent and trustful way before the ship enters a port. Some researches and results, explained in this article, confirm a need for a good verification. If there is no good methodology agreed, then it would not be accepted the solution that the BWMC (Ballast Water Management Convention) 2004 did p...

Transoceanic shipping is the dominant vector for exotic species introductions in the North American Great Lakes. Over 60% of the invaders discovered since the opening of the St. Lawrence Seaway in 1959 are attributable to ballast water release (Ricciardi, 2006). Ocean-going vessels have been required since 1993 to exchange their filled ballast tanks at sea to reduce the abundance and viability ...