EDUCATION, TRAINING, AND ECONOMIC GROWTH

Teaching/Communication/Extension/Profession,

Are Athletes Different ? An Experimental Study Based on the Ultimatum Game

Sport, Athletes, Economic behavior, Experiments, Ultimatum game.

Travelling waves in electroconvection of the nematic Phase 5: A test of the weak electrolyte model

We investigated travelling waves appearing as the primary pattern-forming instability in the nematic Phase 5 (Merck) in the planar geometry in order to test the recently developed weak electrolyte model of ac-driven electroconvection [M. Treiber and L. Kramer, Mol. Cryst. Liq. Cryst 261, 311 (1995)]. Travelling waves are observed over the full conductive range of applied frequencies for three cells of different layer thickness d. We also measured the elastic constants, the electric conductivity, and the dielectric constant. The other parameters of Phase 5 are known, apart from the (relatively unimportant) viscosity $\alpha_1$ and the two parameters of the weak electrolyte model that are proportional to the geometric mean of the mobilities, and the recombination rate, respectively. Assuming a sufficiently small recombination rate, the predicted dependence of the frequency of the travelling waves at onset (Hopf frequency) on d and on the applied frequency agreed quantitatively with the experiments, essentially without fit parameters. The absolute value of the Hopf frequency implies that the geometric mean of the mobilities amounts to $1.1 \times 10^{-10} m^2/(Vs)$.Comment: ReVTeX, 24 pages, 4 figures, to appear in Journal de Physique I

Abnormal Rolls and Regular Arrays of Disclinations in Homeotropic Electroconvection

We present the first quantitative verification of an amplitude description for systems with (nearly) spontaneously broken isotropy, in particular for the recently discovered abnormal-roll states. We also obtain a conclusive picture of the 3d director configuration in a spatial period doubling phenomenon involving disclination loops (CRAZY rolls). The first observation of two Lifshitz frequencies in electroconvection is reported.Comment: 4 pages; 4 figure

On the diameter and incidence energy of iterated total graphs

The total graph of $G$, $\mathcal T(G)$ is the graph whose set of vertices is the union of the sets of vertices and edges of $G$, where two vertices are adjacent if and only if they stand for either incident or adjacent elements in $G$. Let $\mathcal{T}^1(G)=\mathcal{T}(G)$, the total graph of $G$. For $k\geq2$, the $k\text{-}th$ iterated total graph of $G$, $\mathcal{T}^k(G)$, is defined recursively as $\mathcal{T}^k(G)=\mathcal{T}(\mathcal{T}^{k-1}(G)).$ If $G$ is a connected graph its diameter is the maximum distance between any pair of vertices in $G$. The incidence energy $IE(G)$ of $G$ is the sum of the singular values of the incidence matrix of $G$. In this paper for a given integer $k$ we establish a necessary and sufficient condition under which $diam(\mathcal{T}^{r+1}(G))>k-r,$ $r\geq0$. In addition, bounds for the incidence energy of the iterated graph $\mathcal{T}^{r+1}(G)$ are obtained, provided $G$ to be a regular graph. Finally, new families of non-isomorphic cospectral graphs are exhibited

Her Mikveh: Kedushat Yetzirah (Holiness of Creation)

Flyer for Spring 2012 ICS Faculty Fellow Lecture by Dena Eber.https://scholarworks.bgsu.edu/ics_fellow_lectures/1083/thumbnail.jp