Oxygen Ion Energization Observed At High Altitudes

We present a case study of significant heating (up to 8 keV) perpendicular to the geomagnetic field of outflowing oxygen ions at high altitude (12 RE) above the polar cap. The shape of the distribution functions indicates that most of the heating occurs locally (within 0.2–0.4 RE in altitude). This is a clear example of local ion energization at much higher altitude than usually reported. In contrast to many events at lower altitudes, it is not likely that the locally observed wave fields can cause the observed ion energization. Also, it is not likely that the ions have drifted from some nearby energization region to the point of observation. This suggests that additional fundamentally different ion energization mechanisms are present at high altitudes. One possibility is that the magnetic moment of the ions is not conserved, resulting in slower outflow velocities and longer time for ion energization

Oxygen ion energization by waves in the high altitude cusp and mantle

We present a comparative study of low frequency electric field spectral densities and temperatures observed by the Cluster spacecraft in the high altitude cusp/mantle region. We compare the relation between the O+ temperature and wave intensity at the oxygen gyrofrequency at each measurement point and find a clear correlation. The trend of the correlation agrees with the predictions by both an asymptotic mean-particle theory and a test-particle approach. The perpendicular to parallel temperature ratio is also consistent with the predictions of the asymptotic mean-particle theory. At times the perpendicular temperature is significantly higher than predicted by the models. A simple study of the evolution of the particle distributions (conics) at these altitudes indicates that enhanced perpendicular temperatures would be observed over many RE after heating ceases. Therefore, sporadic intense heating is the likely explanation for cases with high temperature and comparably low wave activity. We observe waves of sufficient amplitude to explain the highest observed temperatures, while the theory in general overestimates the temperature associated with the highest observed wave activity, indicating that such high wave activity is very sporadic

The Free State Public Transportation System: A Comparison Between Buses and Taxi Services and Adaptation of ICT Solutions

Conference ProceedingsThis paper explores Information Communication Technologies (ICT) for consideration in the public transportation system in the Free State and how the two main types of public transportation; buses and taxis, are likely to adapt to these technologies. Taxis and buses operation and management of operations are completely different; their differences are likely to affect how each adapts to these technologies. Adaptation to the integrated public transportation system by the bus and taxi users, drivers, and operators will be key to successful ICT integration. Focusing on the benefits that ICT solutions have brought in some regions in the world should not overshadow consideration for possible slow adaptation, lack of acceptance or resistance by stakeholders when applied in a different environment and a different public transportation system. This paper considers the different operational scenarios, government involvement and political will, public – driver – operator participation and willingness and ICT awareness. Whether the technologies and applications will be suitable and adaptable to the existing system and their perceived influence on adaptation to an ICT integrated public transportation system from implementation until there are fully embedded into the system are also considered. Feasibility of some ICT solutions, to the decision makers and operators, considering financial, technical and management feasibility and degree of integration will influence the adaptation process

Treatment of landfill leachate by constructed wetlands

The performance of three constructed wetlands systems treating landfill leachate is described. Two are located in northern Poland (Szadolki near Gdansk and Gatka near Miastko) and one in southern Sweden (Örebro). The constructed wetlands in Szadolki consists of two parallel silty soil beds planted with reed with sub-surface horizontal flow of sewage. The constructed wetland in Gatka is a willow plantation on sandy soil, receiving leachate after preliminary sedimentation in a retention pond. The system in Örebro consists of a series of ponds with a surface flow of leachate, preceded by pre-treatment in an aerated tank with nitrogen stripping. The best treatment efficiencies were observed at Örebro. At the sub-surface flow wetlands in Szadolki and Gatka clogging problems occurred due to the unsatisfactory pre-treatment and low soil hydraulic conductivity resulting in lower treatment efficiencies

Localized practices and globalized futures: challenges for Alaska coastal community youth

An article from Maritime Studies (2015) 14: