Audit report on Taylor County, Iowa for the year ended June 30, 2009

Audit report on Taylor County, Iowa for the year ended June 30, 2009

Audit report on Taylor County, Iowa for the year ended June 30, 2010

Audit report on Taylor County, Iowa for the year ended June 30, 2010

Miten kokemuksesta voi oppia? : Kokemus ja reflektiivinen ajattelu John Deweyn toiminnan filosofiassa

Artikkelissa käsitellään sitä, miten David Kolb perustelee teoksessaan Experiential Learning kokemusoppimisen malliaan, mitä hän esittää John Deweyn siitä sanoneen, sekä verrataan tätä esitystä Dewey-tutkijoiden tulkintaan kokemuksen ja reflektiivisen ajattelun luonteesta Deweyn filosofiassa

Inauguration of the state capitol at Des Moines, Iowa : address delivered before the twentieth General Assembly by Hon. John A. Kasson, upon the invitation of the governor and General Assembly, January 17, 1884.

This brochure is the printed copy of the speech made by Hon. John A. Kasson to the Twentieth General Assembly for the Inauguration of the Iowa State Capitol

Comment on "Selection of the Saffman-Taylor finger width in the absence of surface tension: an exact result"

A Comment on the Letter by Mark Mineev-Weinstein, Phys. Rev. Lett. 80, 2113 (1998). The authors of the Letter offer a Reply.

Nonlinear Saffman-Taylor instability

We show, both theoretically and experimentally, that the interface between two viscous fluids in a Hele-Shaw cell can be nonlinearly unstable before the Saffman-Taylor linear instability point is reached. We identify the family of exact elastica solutions [Nye et al., Eur. J. Phys. 5, 73 (1984)] as the unstable branch of the corresponding subcritical bifurcation which ends up at a topological singularity defined by interface pinchoff. We devise an experimental procedure to prepare arbitrary initial conditions in a Hele-Shaw cell. This is used to test the proposed bifurcation scenario and quantitatively asses its practical relevance.

Reply to Comment on 'Two-finger selection theory in the Saffman-Taylor problem

We clarify the meaning of the results of Phys. Rev. E 60, R5013 (1999). We discuss the use and implications of periodic boundary conditions, as opposed to rigid-wall ones. We briefly argue that the solutions of the paper above are physically relevant as part of a more general issue, namely the possible generalization to dynamics, of the microscopic solvability scenario of selection.

Experiments of periodic forcing of Saffman-Taylor fingers

We report on an experimental study of long normal Saffman-Taylor fingers subject to periodic forcing. The sides of the finger develop a low amplitude, long wavelength instability. We discuss the finger response in stationary and nonstationary situations, as well as the dynamics towards the stationary states. The response frequency of the instability increases with forcing frequency at low forcing frequencies, while, remarkably, it becomes independent of forcing frequency at large forcing frequencies. This implies a process of wavelength selection. These observations are in good agreement with previous numerical results reported in [Ledesma-Aguilar et al., Phys. Rev. E 71, 016312 (2005)]. We also study the average value of the finger width, and its fluctuations, as a function of forcing frequency. The average finger width is always smaller than the width of the steady-state finger. Fluctuations have a nonmonotonic behavior with a maximum at a particular frequency.