The key aspect of the very successful truncated disc model for the low/hard X-ray spectral state in black hole binaries is that the geometrically thin disc recedes back from the last stable orbit at the transition to this state. This has recently been challenged by direct observations of the low/hard state disc from CCD data. We reanalyze the Swift and RXTE campaign covering the 2006 outburst o...

The hard X-ray emission of active galactic nuclei (AGN) is believed to originate from the hot coronae above the cold accretion discs. The hard X-ray spectral index is found to be correlated with the Eddington ratio Lbol/LEdd, and the hard X-ray bolometric correction factor Lbol/LX,2−10keV increases with the Eddington ratio. The Compton reflection is also found to be correlated with the hard X-r...

This paper studies offshoring (defined as a change in firms’ own production location from north to south) and market structure. I develop a model of dynamic oligopoly with offshoring, and estimate it using data from the hard disk industry. The results suggest the incentive to offshore increases as more rivals offshore due to competitive pressure. The possibility of offshoring sets in motion the...

The polymer reference interaction site model theory is investigated for two-dimensional polymer melts composed of freely-jointed hard disk chains and tangent-disk rods. Exact results for the intramolecular pair correlation functions are input into the theory, and predictions of the theory for the intermolecular pair correlation functions are tested via comparison with simulation. The theory is ...

A compact and rugged hardware interface for laptop-based ultrasound recording in the field has been developed. The versatile devices overcome the limitations and drawbacks of previously available solutions. The accompanying recording software enables flexible hard disk recording for both manual and automated operation.

The authors solve the Percus-Yevick equation in two dimensions by reducing it to a set of simple integral equations. They numerically obtain both the pair correlation function and the equation of state for a hard disk fluid and find good agreement with available Monte Carlo results. The present method of resolution may be generalized to any even dimension.

We study the influence of composition changes on the glass transition of binary hard disk and hard sphere mixtures in the framework of mode coupling theory. We derive a general expression for the slope of a glass transition line. Applied to the binary mixture in the low concentration limits, this method allows a fast prediction of some properties of the glass transition lines. The glass transit...

We report on the first demonstration of a quaternary-logical resonatorless optical memory element with information encoded in the structural phase of a single 80 nm gallium nanoparticle. The size of the memory element is comparable with bits in next-generation hard disks, and radically smaller than previously suggested memories exploiting optical resonators. Furthermore, the energy required for...

We model two-dimensional crystals by a configuration space in which every admissible configuration is a hard disk configuration and a perturbed version of some triangular lattice with side length one. In this model we show that, under the uniform distribution, expected configurations in a given box are arbitrarily close to some triangular lattice whenever the particle density is chosen sufficie...

We prove a new lower bound on the critical density ρc of the hard disk model, i.e., the density below which it is possible to efficiently sample random configurations of n non-overlapping disks in a unit torus. We use a classic Markov chain which moves one disk at a time, but with an improved path coupling analysis. Our main tool is an optimized metric on neighboring pairs of configurations, i....