4,483 research outputs found
Driving lamps by induction
An electrodeless lamp circuit with a coil surrounding a krypton lamp is driven by an RF input source. A coil surrounding a mercury lamp is tapped across the connection of the input central to the krypton-lamp coil. Each coil is connected in parallel with separate capacitors which form resonant circuits at the input frequency
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Learning in the Panopticon: ethical and social issues in building a virtual educational environment
This paper examines ethical and social issues which have proved important when initiating and creating educational spaces within a virtual environment. It focuses on one project, identifying the key decisions made, the barriers to new practice encountered and the impact these had on the project. It demonstrates the importance of the ‘backstage’ ethical and social issues involved in the creation of a virtual education community and offers conclusions, and questions, which will inform future research and practice in this area. These ethical issues are considered using Knobel’s framework of front-end, in-process and back-end concerns, and include establishing social practices for the islands, allocating access rights, considering personal safety and supporting researchers appropriately within this contex
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Geolearners: Location-based informal learning with mobile and social technologies
This paper looks at how mobile and social technologies are influencing informal learning in the context of online community membership. The development of mobile technologies that use Global Positioning System (GPS) data to pinpoint geographical location together with the rapidly evolving Web 2.0 technologies supporting the creation and consumption of content suggest a potential for collaborative informal learning linked to location. The research described in this paper asks whether these technologies can provide an effective focus for community activities and, if so, whether this combination of location-awareness, mobile and Web 2.0 technology results in the creation of novel informal learning opportunities. The community selected for study was the Geocaching community, a geographically dispersed group who use mobile and Web 2.0 technologies to link the virtual social spaces of the internet with the physical spaces that surround them
Setting Tech's Agenda for the 21st Century
Clough's presentation to the Georgia Tech Advisory Boar
Evidence Cafés: Overcoming conflicting motivations and timings
Evidence-based practice is increasingly important in creating effective public
services through the balance of high-quality research and valid practice. Yet even
when academics and practitioners work together to use evidence in practice,
barriers emerge. This paper describes research into equitable knowledge exchange
between academia and practice, drawing on data from 15 Evidence Cafés run
across the UK with police forces, involving 378 participants, represented here with
three exemplar Evidence Café case studies. Our findings reveal the differences
between one-way knowledge transfer and two-way, equitable knowledge
exchange, and how champions and effectively designed and implemented
discussion objects can overcome challenges of conflicting motivations and timing.
We conclude that there is a need to reframe knowledge exchange through the
lens of ‘evidence’ and the process of equitable co-creation of new meanings
Reading between the lines: attitudinal expressions in text
This is a brief overview of the starting points a project currently proposed and under evaluation by funding agencies. We discuss some of the linguistic methodology we plan to employ to idenitify and analyze attitudinal expressions in text, and touch briefly on how to evaluate our future results
Vapor-phase growth technique and system for several III-V compound semiconductors Interim scientific report
Vapor phase growth technique for III-V compound semiconductors containing aluminu
Synthesising, using, and correcting for telluric features in high-resolution astronomical spectra
We present a technique to synthesise telluric absorption and emission
features both for in-situ wavelength calibration and for their removal from
astronomical spectra. While the presented technique is applicable for a wide
variety of optical and infrared spectra, we concentrate in this paper on
selected high-resolution near-infrared spectra obtained with the CRIRES
spectrograph to demonstrate its performance and limitation. We find that
synthetic spectra reproduce telluric absorption features to about 2%, even
close to saturated line cores. Thus, synthetic telluric spectra could be used
to replace the observation of telluric standard stars, saving valuable
observing time. This technique also provides a precise in-situ wavelength
calibration, especially useful for high-resolution near-infrared spectra in the
absence of other calibration sources.Comment: 11 pages, 11 figures, accepted for publication in A&A (updated
version
Damping capacity of a model steel structure
The damping capacities of seven model steel structures, each consisting of a heavy steel platform supported on four columns, have been determined from forced vibration tests. The vibrations were produced by an eccentric-mass vibration generator, and the amplitudes ranged from small displacements up to slightly greater than yield displacement. The tests were terminated at the higher amplitudes once fatigue cracks formed in any of the joint welds in the columns. For vibration amplitudes up to a critical amplitude slightly less than yield displacement, the damping factors of the structures were constant, independent of amplitude, and ranged between .15 and .25~ for different structures. At vibration amplitudes greater than the critical amplitude, the damping factors of the structures became functions of amplitude. For example, the damping factor of one test structure increased from .15 to 1.~ as the displacement amplitude increased from 1.1 to 1.4 inches. The last structure tested revealed that a few cycles of vibration at amplitudes greater than the critical amplitude would increase these values slightly. Finally, the results summarized above are compared with the results of: {i) experimental work conducted by Lazan; {ii) reversed loading tests conducted on cantilever beams of similar construction to those tested in the work described in this report; and (iii) experimental work conducted by Hanson
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