Adventures in Tena

Postcard from Haley Parson, during the Linfield College Semester Abroad Program at the Universidad San Francisco de Quito in Ecuado

RRS "Charles Darwin" Cruise 169, 17 Feb-19 Mar 2005. Hydrothermal exploration of the southern Mid-Atlantic Ridge

The principal objective of this cruise was to identify the first site or sites of high temperature hydrothermal venting anywhere on the southern Mid-Atlantic Ridge, to characterize their geological setting, preliminary chemical nature and to identify, where possible, the nature of any vent-endemic species that might inhabit such vents to investigate whether this ridge system might represent a new biogeographic province. Initially we used the TOBI deep-tow sidescan system equipped with a CTD system and optical backscatter sensors, together with Miniature Autonomous Plume Recorders (MAPRs) to identify two new sites in which diagnostic chemically- and particle-laden plumes indicated the presence of high-temperature hydrothermal venting. Subsequently, we used the ABE autonomous underwater vehicle to (1) locate the core of one of these hydrothermal plumes, (2) obtain a detailed map of the underlying seafloor and (3) photograph three discrete hydrothermal sites (2 black-smoker systems, 1 diffuse-flow) and their associated ecosystems. A series of CTD stations were occupied for water column investigations and a number of rock-coring and dredging stations were also undertaken to provide groundtruthing of sidescan sonar images of the Mid-Atlantic Ridge seafloor

Cultural Bubbles in Ecuador

While still in the midst of their study abroad experiences, students at Linfield College write reflective essays. Their essays address issues of cultural similarity and difference, compare lifestyles, mores, norms, and habits between their host countries and home, and examine changes in perceptions about their host countries and the United States. In this essay, Haley Parson describes her observations during her study abroad program at the Universidad San Francisco de Quito in Ecuador

Are STEM Syllabi Gendered? A Feminist Critical Discourse Analysis

This study explored the gendered nature of STEM higher education institution through a feminist critical discourse analysis of STEM course syllabi from a Midwest research university. I explored STEM syllabi to understand how linguistic features such as stance and interdiscursivity are used in the syllabus and how language and discourses used in the syllabus replicate the masculine nature of STEM education. Findings suggest that the discourses identified in the syllabi reinforce traditional STEM academic roles, and that power and gender in the STEM syllabi are revealed through exploration of the themes of knowledge, learning, and the teaching and learning environment created by the language used in the syllabus. These findings inform and extend understanding of the STEM syllabus and the STEM higher education institution and lead to recommendations about how to make the STEM syllabus more inclusive for women

Using hidden Markov models for iterative non-intrusive appliance monitoring

Non-intrusive appliance load monitoring is the process of breaking down a household’s total electricity consumption into its contributing appliances. In this paper we propose an approach by which individual appliances are iteratively separated from the aggregate load. Our approach does not require training data to be collected by sub-metering individual appliances. Instead, prior models of general appliance types are tuned to specific appliance instances using only signatures extracted from the aggregate load. The tuned appliance models are used to estimate each appliance’s load, which is subsequently subtracted from the aggregate load. We evaluate our approach using the REDD data set, and show that it can disaggregate 35% of a typical household’s total energy consumption to an accuracy of 83% by only disaggregating three of its highest energy consuming appliances

Dissipative motion in galaxies with non-axisymmetric potentials

Due to the clumpy nature of the self gravitating gas composing the interstellar medium, it is not clear whether galactic gas dynamics can be discussed in terms of standard hydrodynamics. Nevertheless, it is clear that certain generic properties related to orbital structure in a given potential and the effect of dissipation can be used to qualitatively understand gas motion in galaxies. The effect of dissipation is examined in triaxial galaxy potentials with and without rotating time dependent components. In the former case, dissipative trajectories settle around closed loop orbits when these exist. When they do not, e.g., inside a constant density core, then the only attractor is the centre and this leads to mass inflow. This provides a self regulating mechanism for accession of material towards the centre --- since the formation of a central masses destroys the central density core and eventually stops the accession. In the case when a rotating bar is present, there are usually several types of attractors, including those on which long lived chaotic motion can occur (strange attractors). Motion on these is erratic with large radial and vertical oscillations.Comment: Contibution to the conference on ``Astrophysical Fluids: From Atomic Nuclei to Stars and Galaxies'' (in honour of Giora Shaviv's 60 th birthday). To appear in Physics Report