654 research outputs found

    Antimicrobial Susceptibilities of Aerobic Isolates from Respiratory Samples of Young New Zealand Horses

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    3rd Annual IEEE Energy Conversion Congress and Exposition, ECCE 2011, Phoenix, AZ, 17-22 September 2011This paper presents a method of mitigating the transient overshoots of DC-DC converters operating with large load disturbances. The method involves a small auxiliary power circuit with a complementary control scheme that provides a smooth absorption and release of excess energy from and to the main DC-DC converter in the events of large load changes. This control mechanism interactively mitigates the large transient overshoots which would otherwise appear at the converter output. Since the control scheme involves an adjustable-energy-storage feature, the proposed solution is effective for any level of step-load change within a pre-specified range.Department of Electronic and Information EngineeringRefereed conference pape

    Using interpretative phenomenological analysis to inform physiotherapy practice: An introduction with reference to the lived experience of cerebellar ataxia

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    The attached file is a pre-published version of the full and final paper which can be found at the link below.This article has been made available through the Brunel Open Access Publishing Fund.Qualitative research methods that focus on the lived experience of people with health conditions are relatively underutilised in physiotherapy research. This article aims to introduce interpretative phenomenological analysis (IPA), a research methodology oriented toward exploring and understanding the experience of a particular phenomenon (e.g., living with spinal cord injury or chronic pain, or being the carer of someone with a particular health condition). Researchers using IPA try to find out how people make sense of their experiences and the meanings they attach to them. The findings from IPA research are highly nuanced and offer a fine grained understanding that can be used to contextualise existing quantitative research, to inform understanding of novel or underresearched topics or, in their own right, to provoke a reappraisal of what is considered known about a specified phenomenon. We advocate IPA as a useful and accessible approach to qualitative research that can be used in the clinical setting to inform physiotherapy practice and the development of services from the perspective of individuals with particular health conditions.This article is available through the Brunel Open Access Publishing Fund

    Incommensurate Charge Density Waves in the adiabatic Hubbard-Holstein model

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    The adiabatic, Holstein-Hubbard model describes electrons on a chain with step aa interacting with themselves (with coupling UU) and with a classical phonon field \f_x (with coupling \l). There is Peierls instability if the electronic ground state energy F(\f) as a functional of \f_x has a minimum which corresponds to a periodic function with period πpF{\pi\over p_F}, where pFp_F is the Fermi momentum. We consider pFπa{p_F\over\pi a} irrational so that the CDW is {\it incommensurate} with the chain. We prove in a rigorous way in the spinless case, when \l,U are small and {U\over\l} large, that a)when the electronic interaction is attractive U<0U<0 there is no Peierls instability b)when the interaction is repulsive U>0U>0 there is Peierls instability in the sense that our convergent expansion for F(\f), truncated at the second order, has a minimum which corresponds to an analytical and πpF{\pi\over p_F} periodic \f_x. Such a minimum is found solving an infinite set of coupled self-consistent equations, one for each of the infinite Fourier modes of \f_x.Comment: 16 pages, 1 picture. To appear Phys. Rev.

    Strong damping of phononic heat current by magnetic excitations in SrCu_2(BO_3)_2

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    Measurements of the thermal conductivity as a function of temperature and magnetic field in the 2D dimer spin system SrCu2_2(BO3_3)2_2 are presented. In zero magnetic field the thermal conductivity along and perpendicular to the magnetic planes shows a pronounced double-peak structure as a function of temperature. The low-temperature maximum is drastically suppressed with increasing magnetic field. Our quantitative analysis reveals that the heat current is due to phonons and that the double-peak structure arises from pronounced resonant scattering of phonons by magnetic excitations.Comment: a bit more than 4 pages, 2 figures included; minor changes to improve the clarity of the presentatio

    Ginzburg-Landau theory of phase transitions in quasi-one-dimensional systems

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    A wide range of quasi-one-dimensional materials, consisting of weakly coupled chains, undergo three-dimensional phase transitions that can be described by a complex order parameter. A Ginzburg-Landau theory is derived for such a transition. It is shown that intrachain fluctuations in the order parameter play a crucial role and must be treated exactly. The effect of these fluctuations is determined by a single dimensionless parameter. The three-dimensional transition temperature, the associated specific heat jump, coherence lengths, and width of the critical region, are computed assuming that the single chain Ginzburg-Landau coefficients are independent of temperature. The width of the critical region, estimated from the Ginzburg criterion, is virtually parameter independent, being about 5-8 per cent of the transition temperature. To appear in {\it Physical Review B,} March 1, 1995.Comment: 15 pages, RevTeX, 5 figures in uuencoded compressed tar file

    Editorial: Ethics, Values, and Designer Responsibility

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    As we rely upon increasingly complex sociotechnical systems to support ourselves and, by extension, the structures of society, it becomes yet more important to consider how ethics and values intertwine in design activity. Numerous methods that address issues related to ethics and value-centeredness in design activity exist, but it is unclear what role the design research and practice communities should play in shaping the future of these design approaches. Importantly, how might researchers and practitioners become more aware of the normative assumptions that underlie both their design activity and the design artifacts that result

    Temporary techno-social gatherings? A (hacked) discussion about open practices

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    This paper is rooted in an experimental inquiry of issue-oriented temporary techno-social gatherings or TTGs, which are typically referred to as hackathons, workshops or pop-ups and employ rapid design and development practices to tackle technical challenges while engaging with social issues. Based on a collaboration between three digital practitioners (a producer, a researcher and a designer), qualitative and creative data was gathered across five different kinds of TTG events in London and in Tartu which were held in partnership with large institutions, including Art:Work at Tate Exchange within Tate Modern, the Mozilla Festival at Ravensbourne College and the 2017 Association of Internet Researchers conference hosted in Tartu. By analysing data using an open and discursive approach manifested in both text and visual formats, we reflect on the dynamic and generative characteristics of TTG gatherings while also arriving at our own conclusions as situated researchers and practitioners who are ourselves engaged in increasingly messy webs where new worlds of theory and practice are built

    Frames for Justice Consciousness

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    We describe how UX design students become aware of citizen-engaged design work, and indicate the extent to which a progression toward social justice-focused design work might be possible in a single project cycle. Our study site is a sophomore-level UX design studio at a large Midwestern US university—part of a five-semester sequence in which students engage in a range of projects that address competence in user research, prototyping, and evaluation. The project cycle we focus on directly challenges the apolitical framing in most foundational UX methods literature, explicitly asking students to engage with issues of power disparities. We analyzed three years of digital civics-focused project work (2018 n=6 groups; 2019 n=7; 2020 n=8) undertaken by students in groups of five over a seven-week period, representing the work of 100 students over three years of this course offering. We analyzed the resulting data that supported the development of the Frames for Justice Consciousness model, mapping a range of trajectories of student engagement with social justice-focused design philosophies, highlighting cases where students were able to successfully “pivot” or re-frame the design situation in ways that were consistent with the digital civics philosophy of engagement, addressing goals of participation and advocacy, as well as cases where students tended to repeat common solutionist framings of work within an “apolitical” or product-focused human-centered philosophy. The model facilitates instructor reflection on differing student trajectories that may inform changes to the types of critique given or instructional scaffolds provided in social justice-informed design work
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