11,681 research outputs found
Motion studies of high current arcs using an optical fibre array imaging system
This paper presents an integrated portable measurement system for thestudy of high speed and high temperature unsteady plasma flows such as thosefound in the vicinity of high current switching arcs. The system permits direct andnon-intrusive measurement of arc light emission images with a capture rate of 1million images per second (1MHz), and 8 bit intensity resolution. Novel softwaretechniques are reported to measure arc trajectories. Results are presented on singlehigh current (2kA) discharge events where the electrode and arc runner surfaces areinvestigated using 3D laser scanning methods; such that the position of the arc rootson the runner can be correlated to the measured trajectories. The results showevidence of the cathode arc root stepping along the arc runners<br/
Design and Assessment of an Interactive Digital Tutorial for Undergraduate-Level Sandstone Petrology
This study describes the goals, features and effectiveness of a digital interactive tutorial which was created to provide undergraduates a 'virtual microscope' resource for learning sandstone petrology. The goal of the tutorial is to provide students exposure to the highly visual subject matter of petrography outside the confines of organized laboratory exercises. The hope is that widespread use of such digital interactive formats will allow students to gain high levels of expertise with description and interpretation of earth materials despite the reduced amounts of hands-on laboratory practice that are allowed by modern curricula. Educational levels: Graduate or professional
Motion studies of high current arcs using an optical fibre array imaging system
This paper presents an integrated portable measurement system for thestudy of high speed and high temperature unsteady plasma flows such as thosefound in the vicinity of high current switching arcs. The system permits direct andnon-intrusive measurement of arc light emission images with a capture rate of 1million images per second (1MHz), and 8 bit intensity resolution. Novel softwaretechniques are reported to measure arc trajectories. Results are presented on singlehigh current (2kA) discharge events where the electrode and arc runner surfaces areinvestigated using 3D laser scanning methods; such that the position of the arc rootson the runner can be correlated to the measured trajectories. The results showevidence of the cathode arc root stepping along the arc runners<br/
Mock galaxy catalogs using the quick particle mesh method
Sophisticated analysis of modern large-scale structure surveys requires mock
catalogs. Mock catalogs are used to optimize survey design, test reduction and
analysis pipelines, make theoretical predictions for basic observables and
propagate errors through complex analysis chains. We present a new method,
which we call "quick particle mesh", for generating many large-volume,
approximate mock catalogs at low computational cost. The method is based on
using rapid, low-resolution particle mesh simulations that accurately reproduce
the large-scale dark matter density field. Particles are sampled from the
density field based on their local density such that they have N-point
statistics nearly equivalent to the halos resolved in high-resolution
simulations, creating a set of mock halos that can be populated using halo
occupation methods to create galaxy mocks for a variety of possible target
classes.Comment: 13 pages, 16 figures. Matches version accepted by MNRAS. Code
available at http://github.com/mockFactor
A Student-Driven Approach to Teaching E-commerce
This paper describes an approach to teaching e-commerce at a masters level in a course that is entirely coursework assessed. The approach involves students giving weekly presentations of material they have researched based on fairly detailed subject guidance provided by the lecturer. The approach uses extreme programming as an analogy for the structuring of the content and the process through which learning takes place. The way in which subject material is presented to the students, and the learning cycle which takes place are described. Students develop presentation material in response to stories, which set the context and problems, and tasks which set the detailed areas for investigation. These presentations are done for peers and the tutor and are immediately commented on, leading to the revision of presentation material to appear in an assessed portfolio. The e-commerce syllabus is presented in the context of a commercial or government organization seeking to develop and implement an e-commerce strategy. The agile approach leads to the discovery of new ideas and frameworks by students, and to the development of skills in critically analyzing e-commerce concepts from industrial and academic sources. The paper discusses the student\u27s role as an active developer and deliverer of material in a group environment and the role of the tutor in directing studies, providing support and counsel and assessing student deliverables. In interviews, students commented that the approach was challenging and somewhat daunting, but was a rewarding learning experience. Preconceptions as to what e-commerce involved were challenged through the student-driven research done for the presentations
Bio Motion Project: Final Report
Report on a tentative, integrative model of motion sickness
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