367 research outputs found

    Computer code to interchange CDS and wave-drag geometry formats

    Get PDF
    A computer program has been developed on the PRIME minicomputer to provide an interface for the passage of aircraft configuration geometry data between the Rockwell Configuration Development System (CDS) and a wireframe geometry format used by aerodynamic design and analysis codes. The interface program allows aircraft geometry which has been developed in CDS to be directly converted to the wireframe geometry format for analysis. Geometry which has been modified in the analysis codes can be transformed back to a CDS geometry file and examined for physical viability. Previously created wireframe geometry files may also be converted into CDS geometry files. The program provides a useful link between a geometry creation and manipulation code and analysis codes by providing rapid and accurate geometry conversion

    Development of a floating tidal energy system suitable for use in shallow water

    No full text
    A proposal is made for the use of a traditional streamwaterwheel suspended between two floating catamaranNPL series demi-hulls as means of generating electricalpower. Two prototype devices, of lengths 1.6m and 4.5m,have been developed, constructed and tested. It was foundthat the concept is sound although greater investment isrequired with regards to the materials and bothhydrodynamic and aerodynamic design of the waterwheelto ensure an economically viable system. The workpresented concentrates on practical aspects associated withdesign, construction and trial testing in Southampton waterof the 4.5m prototype. The relatively low cost, ease ofdeployment, and the fact that conventional boat mooringsystems are effective, combine to make this an attractivealternative energy solution for remote communities

    The Use of a Cap-mounted Tri-axial Accelerometer for Measurement of Distance, Lap Times and Stroke Rates in Swim Training

    Get PDF
    This paper will report some of the findings from a trial which recorded accelerometer data from six elite level swimmers (three female and three male, varying primary event stroke and distance) over the course of a regular 15 week training block. Measurements from a head-mounted accelerometer are used to determine when the athlete is swimming, marking of turning points (and therefore distance and lap-time measurements), and is processed by frequency analysis to determine stroke-rate. Comparison with video where available, and with training plans and literature where not, have proven this method to be accurate and reliable for determining these performance metrics. The primary objective of this project was to develop a low-cost, simple and highly usable system for use in swim coaching, feedback from elite coaches has indicated that development of this could be an extremely useful addition to their training regime

    How to Attract a Loon

    Get PDF
    Prospecting is a behavior observed in many species when breeding territories are limited. This behavior has been observed in Common Loons. Yet, in Montana there are an abundance of unoccupied territories and competition for occupied territories is still fierce. We used Common Loon decoys and calls to find out if we could attract non-breeding loons to unoccupied territories. We found that there is a pattern between a loon landing on a territory and the presence of loon decoys (p = 0.11, n = 42). We also discovered a more expedient way (p = 0.05) to collect loon band observations using the decoys (n = 14). The data collected will be helpful in understanding loon behavior and will help guide future management actions

    Rapid prototyping of flexible models - a new methods for model testing?

    No full text
    To date hydroelastic towing tank models are generally segmented, flexible backbone or hinged models which provide an extremely limited representation of the ship structure and record loads only at a finite number of locations between segments. Fully flexible “hydro-structural” models, whilst providing a more accurate structural representation are rarely used due to expense and the complicated nature of their construction. Rapid prototyping is a powerful tool the potential of which is yet to be exploited in the marine industry. By using it to manufacture a realistic ship structure from materials of different properties, new model manufacturing paradigms may be explored. The focus of this paper is the initial findings from an investigation of the use of three-dimensional (3D) printing technologies for manufacturing structurally accurate flexible towing tank models. A detailed assessment is carried out of the material properties of 3D printed materials and their ability to model the scaled structural behaviour of a ship. Scaling implications when considering the realistic ship structure are presented and practical considerations for the construction of 3D printed towing tank models are discussed

    Projections of future air quality are uncertain. But which source of uncertainty is most important?

    Get PDF
    Understanding how air pollution events may change in the future is of key importance to decision makers. Multi-model intercomparison projects focusing on atmospheric chemistry and air quality have been performed to inform the latest IPCC assessments. Future anthropogenic emission changes have generally been the foci of such model experiments, envisaged as the dominant driver of future atmospheric composition. The latest model assessments such as AerChemMIP utilize multi-model ensembles but also have limited individual model ensembles which permit different sources of uncertainty to be characterized. The recent study by Fiore et al. (2022, https://doi.org/10.1029/2021JD035985) specifically considers a multi-model and multi-member ensemble approach. It adds to the quantification of uncertainty in future projections through delineating uncertainty due to model diversity and due to internal or natural climate variability within the climate system, for mean and high PM2.5 air pollution events over the Eastern USA in the 21st century. Exploring the separate roles of internal climate variability and model diversity adds further value to the important research issue of quantifying how future anthropogenic climate change impacts air quality. Future multi-model intercomparisons need to balance the additional knowledge gained from research into understanding multiple sources of uncertainty that can inform decision making vs. the resource costs of performing these experiments using Earth System Models with interactive chemistry

    The Qt distribution of the Breit current hemisphere in DIS as a probe of small-x broadening effects

    Full text link
    We study the distribution 1/sigma dsigma/dQt, where Qt is the modulus of the transverse momentum vector, obtained by summing over all hadrons, in the current hemisphere of the DIS Breit frame. We resum the large logarithms in the small Qt region, to next-to--leading logarithmic accuracy, including the non-global logarithms involved. We point out that this observable is simply related to the Drell-Yan vector boson and predicted Higgs Qt spectra at hadron colliders. Comparing our predictions to existing HERA data thus ought to be a valuable source of information on the role or absence of small-x (BFKL) effects, neglected in conventional resummations of such quantities.Comment: 16 pages, 3 figures, uses JHEP3.cl

    Thiol-Reactive PODS-Bearing Bifunctional Chelators for the Development of EGFR-Targeting [<sup>18</sup>F]AlF-Affibody Conjugates.

    Get PDF
    Site-selective bioconjugation of cysteine-containing peptides and proteins is currently achieved via a maleimide-thiol reaction (Michael addition). When maleimide-functionalized chelators are used and the resulting bioconjugates are subsequently radiolabeled, instability has been observed both during radiosynthesis and post-injection in vivo, reducing radiochemical yield and negatively impacting performance. Recently, a phenyloxadiazolyl methylsulfone derivative (PODS) was proposed as an alternative to maleimide for the site-selective conjugation and radiolabeling of proteins, demonstrating improved in vitro stability and in vivo performance. Therefore, we have synthesized two novel PODS-bearing bifunctional chelators (NOTA-PODS and NODAGA-PODS) and attached them to the EGFR-targeting affibody molecule ZEGFR:03115. After radiolabeling with the aluminum fluoride complex ([18F]AlF), both conjugates showed good stability in murine serum. When injected in high EGFR-expressing tumor-bearing mice, [18F]AlF-NOTA-PODS-ZEGFR:03115 and [18F]AlF-NODAGA-PODS-ZEGFR:03115 showed similar pharmacokinetics and a specific tumor uptake of 14.1 ± 5.3% and 16.7 ± 4.5% ID/g at 1 h post-injection, respectively. The current results are encouraging for using PODS as an alternative to maleimide-based thiol-selective bioconjugation reactions

    The impact of climate mitigation measures on near term climate forcers

    Get PDF
    Here we quantify the regional co-benefits to future air quality on annual to daily mean timescales from implementing mitigation measures to stabilise future climate. Two consistent future emissions pathways are used within the composition-climate model HadGEM3-UKCA: one is a reference pathway of future economic growth and development (REF), whilst the Representative Concentration Pathway 4.5 (RCP4.5) assumes the same development pathway but stabilises anthropogenic radiative forcing at 4.5 W m−2 in 2100. Implementing greenhouse gas (GHG) mitigation measures in RCP4.5 reduces global mean air pollutant emissions by up to 30% in the 2050s, in addition to mitigating climate. Annual mean surface concentrations of ozone and PM2.5 decrease by 10%–20% from the combined reductions in emissions and climate change. The number of days exceeding the World Health Organization's (WHO) daily mean air quality standards are reduced by up 47 days for ozone and 15 days for PM2.5 over different world regions. The air quality co-benefits from mitigation measures are mainly achieved from reductions in anthropogenic emissions, although benefits can be offset due to changes in climate. In terms of anthropogenic climate forcing, while the reduction in global mean effective radiative forcing (ERF) in 2050, relative to the 2000s, due to enacting carbon dioxide mitigation measures (−0.43 W m−2) is enhanced by decreases in tropospheric ozone (−0.26 W m−2) and methane (−0.2 W m−2), it is partially offset by a positive aerosol ERF from reductions in aerosols (+0.35 W m−2). This study demonstrates that policies to mitigate climate change have added co-benefits for global and regional air quality on annual to daily timescales. Furthermore, the effectiveness of the GHG policies in reducing anthropogenic climate forcing is enhanced in the near-term by reductions in ozone and methane despite the increased forcing due to reductions in aerosols
    corecore