Mass Storage Management and the Grid

The University of Edinburgh has a significant interest in mass storage systems as it is one of the core groups tasked with the roll out of storage software for the UK's particle physics grid, GridPP. We present the results of a development project to provide software interfaces between the SDSC Storage Resource Broker, the EU DataGrid and the Storage Resource Manager. This project was undertaken in association with the eDikt group at the National eScience Centre, the Universities of Bristol and Glasgow, Rutherford Appleton Laboratory and the San Diego Supercomputing Center.Comment: 4 pages, 3 figures, Presented at Computing for High Energy and Nuclear Physics 2004 (CHEP '04), Interlaken, Switzerland, September 200

ScotGrid: A Prototype Tier 2 Centre

ScotGrid is a prototype regional computing centre formed as a collaboration between the universities of Durham, Edinburgh and Glasgow as part of the UK's national particle physics grid, GridPP. We outline the resources available at the three core sites and our optimisation efforts for our user communities. We discuss the work which has been conducted in extending the centre to embrace new projects both from particle physics and new user communities and explain our methodology for doing this.Comment: 4 pages, 4 diagrams. Presented at Computing for High Energy and Nuclear Physics 2004 (CHEP '04). Interlaken, Switzerland, September 200

Model-independent measurement of internal stellar structure in 16 Cygni A and B

We present a method for measuring internal stellar structure based on asteroseismology that we call "inversions for agreement." The method accounts for imprecise estimates of stellar mass and radius as well as the relatively limited oscillation mode sets that are available for distant stars. By construction, the results of the method are independent of stellar models. We apply this method to measure the isothermal sound speeds in the cores of the solar-type stars 16 Cyg A and B using asteroseismic data obtained from Kepler observations. We compare the asteroseismic structure that we deduce against best-fitting evolutionary models and find that the sound speeds in the cores of these stars exceed those of the models.Comment: Accepted for publication in The Astrophysical Journa

The New Commandment John 13:34

The story is told of a visit that Bishop Ussher made to a certain Nobleman’s home. During the course of the evening meal the subject of religion was thoroughly discussed. One of the questions that, his host put to the Bishop was this: How many commandments are there? Without hesitation the bishop replied, Eleven, and quoted, as an addition to the Decalogue, the passage in St. John’s Gospel that is to serve as the basis for this thesis: A new commandment give I unto you, that ye love one another, as I have loved you, that ye also love one another

Risk across design domains

Design processes involve risk: to life and limb if the product is unsafe, to the financial health of the company if the product is late, unsuccessful or simply the wrong product, as well as to the emotions and careers of the designers. Many of the risks are shared universally by all designers, but each different industry and each different project faces its own spectrum of serious and minor risks. Different industries have put their methodological effort into finding ways to mitigate the risks they recognise as important. As part of the Across Design project exploring similarities and differences between design processes in different industries, this paper examines how risks are perceived and handled in different types of design process, and proposes that designers and managers can usefully look to other industries for ways to handle risks that are more central for those other industries

Asteroseismology of KIC 8263801:Is it a member of NGC 6866 and a red clump star?

We present an asteroseismic analysis of the Kepler light curve of KIC 8263801, a red-giant star in the open cluster NGC 6866 that has previously been reported to be a helium-burning red-clump star. We extracted the frequencies of the radial and quadrupole modes from its frequency power spectrum and determined its properties using a grid of evolutionary models constructed with MESA. The oscillation frequencies were calculated using the GYRE code and the surface term was corrected using the Ball & Gizon(2014) prescription. We find that the star has a mass of $M/M_{\odot} = 1.793\pm 0.072$, age $t=1.48\pm 0.21$ Gyr and radius $R/R_{\odot} = 10.53\pm 0.28$. By analyzing the internal structure of the best-fitting model, we infer the evolutionary status of the star KIC 8263801 as being on the ascending part of the red giant branch, and not on the red clump. This result is verified using a purely asteroseismic diagnostic, the $\epsilon_{c}-\Delta\nu_{c}$ diagram which can distinguish red giant branch stars from red clump stars. Finally, by comparing its age with NGC 6866 ($t=0.65 \pm 0.1$ Gyr) we conclude that KIC 8263801 is not a member of this open cluster

Mitigating the mass dependence in the Δν\Delta\nu scaling relation of red-giant stars

The masses and radii of solar-like oscillators can be estimated through the asteroseismic scaling relations. These relations provide a direct link between observables, i.e. effective temperature and characteristics of the oscillation spectra, and stellar properties, i.e. mean density and surface gravity (thus mass and radius). These scaling relations are commonly used to characterize large samples of stars. Usually, the Sun is used as a reference from which the structure is scaled. However, for stars that do not have a similar structure as the Sun, using the Sun as a reference introduces systematic errors as large as 10\% in mass and 5\% in radius. Several alternatives for the reference of the scaling relation involving the large frequency separation (typical frequency difference between modes of the same degree and consecutive radial order) have been suggested in the literature. In a previous paper, we presented a reference function with a dependence on both effective temperature and metallicity. The accuracy of predicted masses and radii improved considerably when using reference values calculated from our reference function. However, the residuals indicated that stars on the red-giant branch possess a mass dependence that was not accounted for. Here, we present a reference function for the scaling relation involving the large frequency separation that includes the mass dependence. This new reference function improves the derived masses and radii significantly by removing the systematic differences and mitigates the trend with $\nu_{\rm max}$ (frequency of maximum oscillation power) that exists when using the solar value as a reference.Comment: 12 pages, 7 figures, accepted for publication in MNRA

Response of corn yields to nitrogen fertilization and plant population in Missouri, 1961

Cover title."Progress report no. 1"."This report is a joint contribution of the Department of Soils and the Department of Agricultural Economics of the Missouri Agricultural Experiment Station. It is a progress report of Research Project 455, "The Economics of Fertilizer Use on Corn in Missouri."--Page 2