The Response of a Hot-Wire Anemometer to a Bubble of Air in Water

The sensitivity of peak voltage drop and duration of the change In sensor voltages due to the impaction of different size bubbles are confuted and measured. Excellent agreement between these is found for bubbles somewhat larger than the sensor diameter and smaller than Its effective length in water streams in a range of 1.5 to 9 feet per second. The method suggests a reliable method for sizing bubbles in a water stream. The effects due to nondirect hits are not treated

Energy Spectrum and Turbulent Scales in a Plane Air Jet

The energy spectra and longitudinal length scales measured in a free plane jet are presented. The actual convective velocity was used in determining the scales. The results show a universal spectral distribution along the axis but no obvious similarity in the large scale motion off the axis. The results are limited to x/D \u3c 60. The measured scales suggest a noticeable increase of the microscale along the lateral coordinate but an essentially constant value along the axis. However the macroscales, increasing linearly along the axis do not show any similarity off the axis

Elisabeth Liefmann-Keil: Eine frühe Ordoliberale in dunkler Zeit

Das Jahr 1961 markiert einen Wendepunkt in der deutschsprachigen Sozialpolitiklehre: Das Werk "Ökonomische Theorie der Sozialpolitik", das Elisabeth Liefmann-Keil zu diesem Zeitpunkt veröffentlichte, wurde als ?Ereignis für die wissenschaftliche Sozialpolitik? (Zöllner 1962: 215) und als ?Anschluß an die internationale Diskussion? gefeiert (vgl. Lampert 1992: 120). Zwar war bereits bald nach dem Tod Gustav von Schmollers 1917 im Ausklang der historischen Schule ein heftiger Streit um eine "rationale Sozialpolitik" und deren ökonomisch-theoretische Fundierung entbrannt (vgl. Blümle und Goldschmidt 2003a), doch hatten nicht zuletzt die Wirrungen der nationalsozialistischen, "völkischen" Sozialpolitik, eine frühzeitige Rezeption angelsächsischer, neoklassischer Literatur auch für dieses Feld der Wirtschaftswissenschaften in der Nachkriegszeit erschwert. --

Critical Behavior of Disordered Systems with a Free Surface

The behavior of homogeneous and disordered systems with a free boundary is described on the basis of group theory in the two-loop approximation directly in three-dimensional space. The effect of the free boundary on the regime of the bulk critical behavior is revealed. It is shown that the boundedness of the system slightly affects the regime of the bulk critical behavior in the case of the ordinary transition, whereas this effect is more noticeable in the case of the special transition. Surface critical phenomena are described for homogeneous and disordered systems, and the critical exponents are calculated in the two-loop approximation. It is shown that the effect of impurities is insignificant in the special phase transition, whereas it is more noticeable in the ordinary phase transition. The derived critical exponents are compared with the computer-simulation results.Comment: 19 pages, 2 figure

Classical Particle in a Box with Random Potential: exploiting rotational symmetry of replicated Hamiltonian

We investigate thermodynamics of a single classical particle placed in a spherical box of a finite radius $R$ and subject to a superposition of a $N-$dimensional Gaussian random potential and the parabolic potential with the curvature $\mu>0$. Earlier solutions of $R\to \infty$ version of this model were based on combining the replica trick with the Gaussian Variational Ansatz (GVA) for free energy, and revealed a possibility of a glassy phase at low temperatures. For a general $R$, we show how to utilize instead the underlying rotational symmetry of the replicated partition function and to arrive to a compact expression for the free energy in the limit $N\to \infty$ directly, without any need for intermediate variational approximations. This method reveals striking similarity with the much-studied spherical model of spin glasses. Depending on the value of $R$ and the three types of disorder - short-ranged, long-ranged, and logarithmic - the phase diagram of the system in the $(\mu,T)$ plane undergoes considerable modifications. In the limit of infinite confinement radius our analysis confirms all previous results obtained by GVA.Comment: 46 pages, 4 figures; This version corrects a few more typos discovered in the published versio