Heinz Isler: shells for two churches

This paper describes the concept, design and realisation of two churches where Heinz Isler (1926-2009) was responsible for the structural design and in one case also for the architectural concept. One example, the Heilig Geist Kirche (Holy Spirit Church) Lommiswil, near Solothurn, Switzerland (1967) includes, unusually for Isler, a “hypar” shell whilst the other, the “Steinkirche” of the Evangelische Kirchgemeinde in Cazis, Switzerland (1996), is derived directly from given natural forms

Power and rural landscapes in early medieval Galicia (400-900 ad ): towards a re-incorporation of the archaeology into the historical narrative

This paper aims to bring together hitherto neglected archaeological data about the early medieval landscapes of Galicia (north-west Spain), in order to understand the social transformations this ‘peripheral’ region underwent between the fifth and the ninth centuries and to frame them in the context of wider European debates. Despite its many limitations, the archaeology reveals that until the middle of the seventh century, the late antique society of Gallaecia experienced a previously unsuspected vitality. At this point a socio-political fragmentation occurred, which was characterized by the strengthening of local power, until a further change took place with the progressive incorporation of Galicia into the Asturian kingdom in the ninth century

Testing for PPP in Australia: evidence from unit root tests against nonlinear trend stationarity alternatives

This paper tests for the empirical fulfilment of PPP in Australia (1977-2004). Previous research focuses on the presence of structural breaks and fails to find any support for PPP (Darne and Hoarau, 2008, Henry and Olekalns, 2002). In contrast, we find that the real exchange rate is stationary once we account for a more general specification of the nonlinear deterministic components based on a Chebishev polynomials approximation

Energy dissipation and flux laws for unsteady turbulence

Direct Numerical Simulations of unsteady spatially periodic turbulence with time-dependent rms velocity u′(t) and integral length-scale L(t) show that not only the instantaneous energy dissipation rate but also the instantaneous energy flux at intermediate wavenumbers scales as View the MathML source where U0 and L0 are velocity and length scales characterizing initial or overall unsteady turbulence conditions. These high Reynolds number scalings are qualitatively different from the well-known u′(t)3/L(t) cornerstone scalings of equilibrium turbulence where the energy flux and dissipation are exactly balanced at all times