6,895 research outputs found

    Geopotential models in the Australian region

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    The ability of three high-order geopotential models (OSU81, GPM2 and OSU86E) to recover the gravity anomaly field (delta g) in the Australian region was tested. The region was divided into 2 x 2 deg blocks, and the mean and rms of the residual gravity (delta g measured - delta g modeled) was found to estimate the fit of the model to the point gravity data. The results showed that OSU81 and GPM2 performed similarly, recovering the delta g with a mean value of less than plus or minus 5 mGal in 63 and 70 percent of the blocks, respectively. However, both these models achieved a fit of worse that was plus or minus 13 mGal in 6 to 7 percent of cases. These were in areas either on or near the coast, or in the Central Australian region, inferring that for a precise geoid slope determination in these regions, a detailed analysis of delta g in region is needed. On the other hand, OSU86E produced a very good result, having a mean fit of less than plus or minus 5 mGal in 80 percent of the blocks, and worse than plus or minus 13 mGal in only 1 percent of cases. The rms values for this model were also improved over the other two models, indicating that for applications requiring highest precision, the preferred model is OSU86E

    The Lore of Low Methane Livestock:Co-Producing Technology and Animals for Reduced Climate Change Impact

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    Methane emissions from sheep and cattle production have gained increasing profile in the context of climate change. Policy and scientific research communities have suggested a number of technological approaches to mitigate these emissions. This paper uses the concept of co-production as an analytical framework to understand farmers’ evaluation of a 'good animal’. It examines how technology and sheep and beef cattle are co-produced in the context of concerns about the climate change impact of methane. Drawing on 42 semi-structured interviews, this paper demonstrates that methane emissions are viewed as a natural and integral part of sheep and beef cattle by farmers, rather than as a pollutant. Sheep and beef cattle farmers in the UK are found to be an extremely heterogeneous group that need to be understood in their specific social, environmental and consumer contexts. Some are more amenable to appropriating methane reducing measures than others, but largely because animals are already co-constructed from the natural and the technical for reasons of increased production efficiency

    Occupy: 'struggles for the common or an 'anti-politics of dignity? Reflections on Hardt and Negri and John Holloway

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    This article provides a critical examination of Michael Hardt and Antonio Negri’s and John Holloway’s theory of revolutionary subjectivity, and does so by applying their theories to the Occupy movement of 2011. Its central argument is that one should avoid collapsing ‘autonomist’ and ‘open’ Marxism, for whilst both approaches share Tronti’s (1979) insistence on the constituent role of class struggle, and also share an emphasis on a prefigurative politics which engages a non-hierarchical and highly participatory politics, there nevertheless remain some significant differences between their approaches. Ultimately, when applied to Occupy Movement whilst their theory isn’t entirely unproblematic, I will argue that Hardt and Negri’s ‘autonomist’ approach offers the stronger interpretation, due mainly to their revised historical materialism

    Nonprofit governance: The shape of board organisation communication

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    This qualitative study investigated corporate governance and management practices, with a particular focus on communications between the board and senior management, in two disability service organisations in the nonprofit sector. Fifteen interviewees participated across the two case studies and their insights and contributions were thematically analysed. Among the key findings was a significant contrast in communication processes across the two organisations. In one, communications were tightly controlled by the CEO (hourglass-shaped approach) and, in the second, there was a more accessible communication process between the board and senior management. This paper explores these two communication models

    Robotic milking technologies and renegotiating situated ethical relationships on UK dairy farms

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    Robotic or automatic milking systems (AMS) are novel technologies that take over the labor of dairy farming and reduce the need for human-animal interactions. Because robotic milking involves the replacement of 'conventional' twice-a-day milking managed by people with a system that supposedly allows cows the freedom to be milked automatically whenever they choose, some claim robotic milking has health and welfare benefits for cows, increases productivity, and has lifestyle advantages for dairy farmers. This paper examines how established ethical relations on dairy farms are unsettled by the intervention of a radically different technology such as AMS. The renegotiation of ethical relationships is thus an important dimension of how the actors involved are re-assembled around a new technology. The paper draws on in-depth research on UK dairy farms comparing those using conventional milking technologies with those using AMS. We explore the situated ethical relations that are negotiated in practice, focusing on the contingent and complex nature of human-animal-technology interactions. We show that ethical relations are situated and emergent, and that as the identities, roles, and subjectivities of humans and animals are unsettled through the intervention of a new technology, the ethical relations also shift. © 2013 Springer Science+Business Media Dordrecht

    Ground‐based measurements of NOx and total reactive oxidized nitrogen (NOy) at Sable Island, Nova Scotia, during the NARE 1993 summer intensive

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    Measurements of NO, NO2, and total reactive oxidized nitrogen (NOy) were added to ongoing measurements of aerosols, CO, and O3 at Sable Island (43°55′N, 60°01′W), Nova Scotia, during the North Atlantic Regional Experiment (NARE) 1993 summer intensive. Ambient levels of NOx and NOy were found to be highly variable, and elevated levels can be attributed to the transport of polluted continental air or presumably to relatively fresh emissions from sources upwind (e.g., ship traffic). The median values for NOx and NOy are 98 and 266 parts per trillion by volume (pptv), respectively. A multiday pollution episode occurred during which elevated NOx and NOy were observed with enhanced levels of O3, CO, and condensation nuclei. Air masses of recent tropical marine origin characterized by low and constant levels of O3 and CO were sampled after Hurricane Emily. The correlation between ozone and CO is reasonably good, although the relation is driven by the single pollution episode observed during the study. The correlation of O3 with NOy and with NOy‐NOx is complicated by the presumed NOy removal processes in the marine boundary layer. Examination of the radiosonde data and comparisons of the surface data with those obtained on the overflying aircraft provide clear indications of vertical stratification above the site

    Added mass of whipping modes for ships at high Froude number by a free surface boundary element method coupled with strip theory

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    Accurate prediction of the whipping response of a ship's structure following a wave impact is fundamental to both the prediction of instantaneous local stresses and global fatigue life assessment. In particular the added mass effect of the surrounding water has a profound effect on the modal frequencies. ``Strip theory'', routinely used for analysis of rigid body motions of ships in waves, is extended in this paper to include ship flexure. Moreover, the theoretical foundation of the method is discussed and it is shown that, although the theory becomes invalid for rigid body motions of high-speed vessels, the ship flexure problem is an ideal application of the theory. The associated two-dimensional free surface gravity wave problem is solved using a boundary element method based on wave functions given by Wehausen and Laitone (1960), which is also described. Results are validated against a fully three-dimensional solution, and incorporation of the added mass into a finite element model is shown to give excellent agreement with full scale measurements

    Spectral transform simulations of finite amplitude double-diffusive instabilities in two dimensions

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    Simulations of double-diffusion with a two-dimensional, vertical plane spectral transform model reveal details of finite amplitude behavior in salt finger, interleaving and diffusive instabilities. Within the range of fluid parameters studied (3 \u3c σ \u3c 10, .1 \u3c r \u3c .5), infinite, fastest-growing fingers are unstable to Holyer\u27s (1984) nonoscillatory instability and are completely disrupted by it. Finite fingers localized on density steps are also disrupted. Initialized density steps are eroded (the gradients reduced). Fluxes and other diagnostic quantities were determined for salt finger fields at statistical stationarity. These fields contain transitory, irregular finger structures. Fluxes decline steeply as Rfp increases. A single point of comparison of buoyancy flux with ocean measurement yielded good agreement. The dependence of flux ratio on the stability parameter is similar to the linear theory prediction for fastest-growing, infinite fingers and does not increase as Rfp approaches 1, in contrast to laboratory measurements. Holyer\u27s (1984) Floquet theory is extended to the case of nonzero, density compensating, horizontal gradients, and, together with the simulation results, encourages the interpretation of the interleaving instability as being sloping salt fingers. A few preliminary simulations of the diffusive regime indicate very complex behavior. A growing oscillatory perturbation can lead to subcritical convective instability. Such motions sharpen initialized density steps. In the presence of a step, unstable motions are supported even when the fluid is linearly stable to both convection and the diffusive mode

    Ideas and Enhancements Related to Mobile Applications to Support Type 1 Diabetes

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    Background: Mobile devices have become increasingly important to young people who now use them to access a wide variety of health-related information. Research and policy related to the integration of health information and support with this technology do not effectively consider the viewpoint of a younger patient. Views of young people with type 1 diabetes are vital in developing quality services and improving their own health-related quality of life (HRQOL), yet research on their lifestyle and use of Web and mobile technology to support their condition and in non–health-related areas is sparse. Objective: To develop insight into young people with type 1 diabetes and their current use of Web and mobile technology and its potential impact on HRQOL. This can be achieved by constructing an in-depth picture of their day-to-day experiences from qualitative interviewing and exploring how they make use of technology in their lives and in relation to their condition and treatment. The goal was then to build something to help them, using the researcher’s technical expertise and seeking users’ opinions during the design and build, utilizing sociotechnical design principles. Methods: Data were collected by semistructured, in-depth qualitative interviews (N=9) of young people with type 1 diabetes aged 18-21. Interviews were transcribed and loaded onto NVivo for theme identification. Data analysis was undertaken during initial interviews (n=4) to locate potential ideas and enhancements for technical development. Latter interviews (n=5) assisted in the iterative sociotechnical design process of the development and provided additional developmental ideas. Results: Six themes were identified providing an understanding of how participants lived with and experienced their condition and how they used technology. Four technological suggestions for improvement were taken forward for prototyping. One prototype was developed as a clinically approved app. A number of ideas for new mobile apps and enhancements to currently existing apps that did not satisfactorily cater to this age group’s requirements for use in terms of design and functionality were suggested by interviewees but were not prototyped. Conclusions: This paper outlines the nonprototyped suggestions from interviewees and argues that young people with type 1 diabetes have a key role to play in the design and implementation of new technology to support them and improve HRQOL. It is vital to include and reflect on their suggestions as they have a radically different view of technology than either their parents or practitioners. We need to consider the relationship to technology that young people with type 1 diabetes have, and then reflect on how this might make a difference to them and when it might not be a suitable mechanism to use

    Universality of rain event size distributions

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    We compare rain event size distributions derived from measurements in climatically different regions, which we find to be well approximated by power laws of similar exponents over broad ranges. Differences can be seen in the large-scale cutoffs of the distributions. Event duration distributions suggest that the scale-free aspects are related to the absence of characteristic scales in the meteorological mesoscale.Comment: 16 pages, 10 figure
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