New considerations on scale extrapolation of wing pressure distributions affected by transonic shock-induced separations

Use of this analytical parameter, it is shown, highlights the distinction between cases which are dominated by trailing-edge separation, and those for which separation at the shock foot is dominant. Use of the analytical parameter and the distinction noted above greatly improves the correlation of separation data and the extrapolation of wind tunnel data to flight conditions

Protons as the prime contributors to the storm time ring current

Following a large magnetic storm (17 June 1972), Explorer 45 measured the equatorial particle populations and magnetic field. Using data obtained during the symmetic recovery phase, it is shown that through a series of self-consistent calculations, the measured protons with energies from 1 to 872 keV, can account for the observed ring current magnetic effects within experimental uncertainities. This enables an upper limit to be set for the heavy ion contribution to the storm time ring current

Self-Referential Noise and the Synthesis of Three-Dimensional Space

Generalising results from Godel and Chaitin in mathematics suggests that self-referential systems contain intrinsic randomness. We argue that this is relevant to modelling the universe and show how three-dimensional space may arise from a non-geometric order-disorder model driven by self-referential noise.Comment: Figure labels correcte

Two Nucleon-States in a Chiral Quark-Diquark Model

We study the ground and first excited states of nucleons in a chiral quark-diquark model. We include two quark-diquark channels of the scalar-isoscalar and axial-vector-isovector types for the nucleon states. The diquark correlation violating the spin-flavor SU(4)$_{SF}$ symmetry allows to treat the two quark-diquark channels independently. Hence the two states appear as the superpositions of the two quark-diquark channels; one is the nucleon and the other is a state which does not appear in the SU(4)$_{SF}$ quark models. With a reasonable choice of model parameters, the mass of the excited state appears at around 1.5 GeV, which we identify with the Roper resonance N(1440).Comment: 11 pages, 5 figures. Errors are corrected. Conclusions are not affecte

High Reynolds number tests of a C-141A aircraft semispan model to investigate shock-induced separation

Results from a high Reynolds number transonic wind tunnel investigation are presented. Wing chordwise pressure distributions were measured over a matrix of Mach numbers and angles-of-attack for which shock-induced separations are known to exist. The range of Reynolds number covered by these data nearly spanned the gap between previously available wind tunnel and flight test data. The results are compared with both flight and low Reynolds number data, and show that use of the semispan test technique produced good correlation with the prior data at both ends of the Reynolds number range, but indicated strong sensitivity to details of the test setup

Feasibility study of the transonic biplane concept for transport aircraft application

Investigations were conducted to evaluate the feasibility of a transonic biplane consisting of a forward-mounted swept-back lower wing, a rear-mounted swept-forward upper wing, and a vertical fin connecting the wings at their tips. This wing arrangement results in significant reductions in induced drag relative to a monoplane designed with the same span, and it allows for a constant-section fuselage shape while closely matching an ideal area distribution curve for M = 0.95 cruise. However, no significant reductions in ramp weight were achieved for the biplane relative to a monoplane with the same mission capability. Flutter analyses of the biplane revealed both symmetric and antisymmetric instabilities that occur well below the required flutter speed. Further studies will be required to determine if acceptable flutter speeds can be achieved through the elimination of the instabilities by passive means or by active controls. Configurations designed for other missions, especially those with lower Mach numbers and lower dynamic pressures, should be examined since the geometries suitable for those design constraints might avoid the weight penalties and flutter instabilities which prevent exploitation of induced drag benefits for the configuration studied

Diquarks: condensation without bound states

We employ a bispinor gap equation to study superfluidity at nonzero chemical potential: mu .neq. 0, in two- and three-colour QCD. The two-colour theory, QC2D, is an excellent exemplar: the order of truncation of the quark-quark scattering kernel: K, has no qualitative impact, which allows a straightforward elucidation of the effects of mu when the coupling is strong. In rainbow-ladder truncation, diquark bound states appear in the spectrum of the three-colour theory, a defect that is eliminated by an improvement of K. The corrected gap equation describes a superfluid phase that is semi-quantitatively similar to that obtained using the rainbow truncation. A model study suggests that the width of the superfluid gap and the transition point in QC2D provide reliable quantitative estimates of those quantities in QCD.Comment: 7 pages, 3 figures, REVTEX, epsfi

The Effect of Various Pasture-based Systems of Milk Production on Animal Performance in the Northeast Region of Ireland

End of Project ReportThe potential of Irish soils to grow grass throughout the year and success in utilizing grass are key factors affecting output and profitability of dairy production systems (Shalloo et al., 2004). In the Northeast region of Ireland, the potential grazing season is shortened due to impeded land drainage, topography, high rainfall and northerly aspect. The main focus of the Ballyhaise research programme is to develop more sustainable production systems suitable to the limitations of the region with a specific focus on grass growth and utilization. Progress in these technologies will improve the competitiveness of dairying in the Northeast region. We are also now faced with a new economic environment with market forecasts predicting a steady decline in dairy product prices for Irish dairy farmers while input prices continue to increase. It has been shown from previous studies that dairy farmers need to expand and/or increase the efficiency of their dairy operation to maintain their real farm incomes over the coming years (Breen and Hennessey, 2003). It is likely that land purchase price will continue to be high in future years. Firstly, dairy farmers can continue at their current level of production and efficiency, and suffer a decline in farm profit as milk price falls. It is likely that greater amounts of milk quota will become available in the coming years; therefore many dairy farmers will have the option to increase production. Expansion opportunities will be limited by the key constraints such as labour supply and cost, capital cost, milk quota availability and price and availability of land around the milking parlour. Labour efficient work practices will have to be adopted on farms to allow one operator to manage a greater number of cows. The objective of this experiment was to examine the effect of two divergent pasture-based systems of milk production on animal performance over a two-year period and to subsequently describe the optimum system for dairy farmers in the Northeast region both now and into the future