103 research outputs found

    Observation of Quantum Shock Waves Created with Ultra Compressed Slow Light Pulses in a Bose-Einstein Condensate

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    We have used an extension of our slow light technique to provide a method for inducing small density defects in a Bose-Einstein condensate. These sub-resolution, micron-sized defects evolve into large amplitude sound waves. We present an experimental observation and theoretical investigation of the resulting breakdown of superfluidity. We observe directly the decay of the narrow density defects into solitons, the onset of the `snake' instability, and the subsequent nucleation of vortices.Comment: 15 pages, 5 figure

    Ableism and Exclusion: Challenging Academic Cultural Norms in Research Communication

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    Academic institutions are abelist. This, however, does not have to be the case. How do individuals involved in research management address this culture? In the context of the drastic changes in Higher Education since the 1990s, and an increasing emphasis on equality and inclusion, initiatives such as Athena Swan and the Race Equality Charter have led to more awareness of exclusionary practices. However, statistics on disability highlight serious issues in relation to disclosure rates for staff and staff report being stigmatised and their career choices undermined or invalidated. This can be particularly true for those who research into or around ableism. In this environment how can research managers raise awareness and empower all academics to ask for and gain adjustments to support their work? How has the Covid-19 pandemic and the impact on higher education institutions and their finances affected this issue? In this paper we consider some of the challenges of conducting research on ableism in academia and what it can tell us. We then discuss the changes that can be made to research management that would help address and challenge the ableist academic culture. This would be achieved through raising expectations, placing inclusivity and accessibility at the heart of research communication and encouraging, equipping and challenging the academic community to embed these practices in the dissemination of their research

    People objects : 3-D modeling of heads in real-time

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    Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 1998.Includes bibliographical references (p. 54-59).by Thomas E. Slowe.S.M

    A High Flux Source of Cold Rubidium

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    We report the production of a continuous, slow, and cold beam of 87-Rb atoms with an unprecedented flux of 3.2 x 10^12 atoms/s and a temperature of a few milliKelvin. Hot atoms are emitted from a Rb candlestick atomic beam source and transversely cooled and collimated by a 20 cm long atomic collimator section, augmenting overall beam flux by a factor of 50. The atomic beam is then decelerated and longitudinally cooled by Zeeman slowing

    The role of the institution in scholarly publishing

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    In providing a supportive and sustainable research environment, the institution has a key role to play in scholarly publishing. Whether that be as a guide, assisting researchers through the maze of publishing options and access to specialist audiences, or as an auditor for funders, or as a financer, agreeing article processing charges and subsidising website maintenance. Equally, the institution is the specialist systems developer and protector of the ‘unpublished’ research. This ensures repositories meet the needs of their researchers. In a wider context, the institution is the rewarder of scholarly publishing though promotions and the horizon scanner, preparing researchers for what is coming next. This piece looks at how the multiple roles of the institution in scholarly publishing impact researchers

    A Zeeman Slower based on magnetic dipoles

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    A transverse Zeeman slower composed of an array of compact discrete neodymium magnets is considered. A simple and precise model of such a slower based on magnetic dipoles is developed. The theory of a general Zeeman slower is modified to include spatial nonuniformity of the slowing laser beam intensity due to its convergence and absorption by slowed atoms. The slower needs no high currents or water cooling and the spatial distribution of its magnetic field can be adjusted. In addition the slower provides a possibility to cool the slowed atoms transversally along the whole length of the slower. Such a slower would be ideal for transportable optical atomic clocks and their future applications in space physics.Comment: 17 pages, 9 figure

    Supporting Open Access at Kent – new staff roles

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    Open Access has been supported at the University of Kent from an early stage with the establishment of the Kent Academic Repository in 2007. Initially, this work was accommodated within the existing library staff structure, but the pace of change, funder requirements and a new university plan meant that support for Open Access needed to become explicit and a research support team was established using a matrix working system . This article details this new structure and reflects on the benefits and challenges it brings

    Design of a prototyping press for 3-d monolithic compliant mechanisms

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    Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references (p. 38).The Precision Systems Design and Manufacturing Lab at the Massachusetts Institute of Technology has the need for a metal forming device capable of applying a plastic deformation to two-dimensional sheet metal templates of up to 1/8-inch thickness and 8-inch diameter in order to transform them into prototype three-dimensional monolithic compliant mechanisms. These mechanisms have applications in industrial positioning as they are highly accurate and free from normal performance reducers such as friction, wear, and backlash. This thesis presents the design of a prototyping press capable of achieving the deformation required to produce the 3DMCMs from their 2D templates. The prototyping press that is developed herein utilizes a multiple-piston, hydropneumatic cylinder to deliver up to 5,000 lbf over a 4-inch stroke. The press offers force sensing to within 10%, displacement sensing to within 0.005 inches, and rate control centered around a 6-inch per minute average rate. It is powered by a compressed air supply at up to 100 psi and motion is controlled by a single electrical solenoid shut-off valve.by Thomas J. Slowe.S.B

    Making research evaluation processes in Europe more transparent

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    Researchers repeatedly cite career advancement as a key incentive for their practices and behaviours. This is critical to understanding the pace of change in scholarly communications, as those researchers inclined to innovate or experiment with new forms of research outputs, methodologies, or communication styles risk being penalised by the evaluation system used by many research institutions that are slow to adapt to the modern research environment. Sarah Slowe, Gareth Cole, Jon Tennant and Charlie Rapple are gathering data on current promotion and hiring guidelines used throughout Europe and will analyse how these compare to researchers’ attitudes of “publish or perish” and the impact factor as the key determining factor for career advancement. A number of recommendations will follow from this analysis, with the ultimate aim of fostering a more informed evaluation, promotion, and recruitment system for researchers

    Future perspectives on sustainable tribology

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    AbstractThis paper highlights the future perspectives of sustainable tribology by examining the economic, environmental and social impact of three tribological case studies. One case study examines the sustainability and durability of micro-CHP systems looking the tribological phenomena generated within a scroll expander system. The scroll is the main part of a specific micro-CHP system and experiences wear and cavitation damage. The tribological optimization of the scroll expander improves the sustainability of the micro-CHP unit while it has a serious economic and environmental impact to the consumers and to the society in general. Another case study is focused on friction and wear performance of lifeboat launch slipways. The causes of high friction and wear during the RNLI's lifeboat launches along an inclined slipway are investigated with a view to reducing the environmental impact due to slipway panel wear and lubricant release into the marine environment. The project encompasses the sustainable design of slipway panels using design modifications based on tribological investigations to double their lifespan, while environmental and economic impact was significantly reduced by the use of biodegradable greases and water as lubricants. The final case study involves an investigation of recycled plastic materials to replace polyurethane used on skateboard wheels, scooters and similar applications. Polyurethane (PU) is difficult to recycle. With the dwindling resources and environmental problems facing the world today, recycling for both waste reduction and resource preservation has become an increasingly important aspect of sustainability. The tribological results showed that recycled polycarbonate plastic can effectively act as a substitute to polyurethane wheels. Moreover, sustainability considerations showing the environmental benefits of the use of recycled plastics over PU include reducing the CO2 footprint by 50% and the energy consumed by 60%, among other benefits. These case studies emphasise the importance of sustainable tribology in our epoch showing that increased sustainability performance can be achieved through tribology to a significant extent in many cases, providing stability to our world and more viable long term growth to our societies
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