We consider a family of linear control systems ẋ = Ax+αBu where α belongs to a given class of persistently exciting signals. We seek maximal α-uniform stabilisation and destabilisation by means of linear feedbacks u = Kx. We extend previous results obtained for bidimensional singleinput linear control systems to the general case as follows: if the pair (A,B) verifies a certain Lie bracket gener...

Previous growth-rate studies covering 14 dinosaur taxa, as represented by 31 data sets, are critically examined and reanalyzed by using improved statistical techniques. The examination reveals that some previously reported results cannot be replicated by using the methods originally reported; results from new methods are in many cases different, in both the quantitative rates and the qualitativ...

Secchi " On The Laplace Distribution of Firms Growth Rates ". We present a new the description of the empirical results and we try to provide better justification for the theoretical assumptions constituting the base of our analysis. In the present version we introduce a new more general version of the main theorem that helps to clarify the assumption about micro-shocks distribution, the nature...

In this paper we define a class of infinite rooted trees called transition trees for which the growth function can be calculated using powers of a nonnegative matrix. We show that if this matrix is primitive, has spectral radius greater than 1, and does not have 1 as an eigenvalue, then the tree has exponential growth and the growth rate is the spectral radius of the matrix. We also describe a ...

We study the abelian sandpile growth model, where n particles are added at the origin on a stable background configuration in Z. Any site with at least 2d particles then topples by sending one particle to each neighbor. We find that with constant background height h ≤ 2d − 2, the diameter of the set of sites that topple has order n. This was previously known only for h < d. Our proof uses a str...

I describe techniques for making precise measurements of the growth rates of the principal facets of ice crystals. Particular attention is paid to identifying and reducing systematic errors in the measurements, as these have plagued earlier attempts to determine ice growth rates. I describe the details of an experimental apparatus we are currently using, and I describe some preliminary results ...

We describe several important features of annual firm growth rate dynamics. Specifically, we report three major findings, some of which were previously known for certain subsets of U.S. firms and are here shown to obtain for the entire universe of U.S. business firms, and others that are apparently novel. First, the distribution of log growth rates overall are well-characterized by the so-calle...

Using sequence data to infer population dynamics is playing an increasing role in the analysis of outbreaks. The most common methods in use, based on coalescent inference, have been widely used but not extensively tested against simulated epidemics. Here, we use simulated data to test the ability of both parametric and non-parametric methods for inference of effective population size (coded in ...

In endogenous growth theory models exist which are characterized by local and global indeterminacy. These concepts imply that economies differ with respect to their growth rates on the transition path (local indeterminacy) as well as their long−run growth rates (global indeterminacy). While the empirical density function of the levels of aggregate GDP has been the subject of a great many studie...

[1] We calculate growth rates for extraordinary mode Saturnian kilometric radiation generated by the electron cyclotron maser instability using a ring‐type (DGH) electron phase distribution model fitted to measured electron energy dist r ibut ions in Saturn’s auroral acceleration region. The observed distributions are unstable in spatially isolated regions of transverse linear size of order 10 ...