Optical classification of random image fields using spectral synthetic discriminant functions

It is shown that the problem of classification of images that have the perfectly random nature may be solved with the help of synthetic discriminant functions being synthesized by least-squares technique to separate linearly the power spectra of the corresponding random image fields. The realization of the proposed method by means of an optical technique is discussed, and its efficiency is illustrated by two examples of real-life texture classification.     

Electrolytic nucleation of silver on a glassy carbon electrode: Part I. Mechanism of critical nucleus formation

The initial stage of electrodeposition of silver on a glassy carbon electrode is investigated using a double-pulse potentiostatic method. Data are obtained for the concentration dependence of the steady-state nucleation rate I and conclusions are drawn for the probable mechanism of critical nucleus formation.     

High-field vs. low-field magneto-transport in a percolating medium

Recent theoretical and numerical work on high-field magneto-transport in a percolating medium is described and compared to earlier work on weak-field magneto-transport in such systems. While the weak-field behavior is well described by the simple nodes-links picture, which ignores blobs and loops on a scale smaller than the percolation correlation length ξ_p, the strong-field behavior is extremely sensitive to those features. The critical behavior at strong magnetic fields H near the percolation threshold is governed by competition between the usual H=0 fixed point and a new H=∞ fixed point. Which of those fixed points dominates the behavior is determined by the relative sizes of two characteristic lenghts: the percolation correlation length ξ_p and a new, magnetic field dependent length ξ_H.     

Decay modes of muonic lithium-hydrogen molecules

Radiative, Auger and predissociation decay modes of muonic lithium-hydrogen molecule, Liμh, (h = p, d or t is a hydrogen isotope) are considered. Results obtained for the corresponding reaction rates indicate that predissociation is a dominating decay mode for h = p, d while Auger decay dominates for h = t. The calculated conversion coefficient is significantly larger than that for helium muonic molecule and ranges between 37 and 42 (on the basis of one electron) depending on isotope composition of the molecule. Reaction rates for rotational 1 → 0 transitions in Liμh and Heμh due to inner Auger process are also calculated.     

X-ray and magnetic birefringence studies of some lanthanide metallomesogens with Schiff's base ligands

Low angle X-ray scattering studies have been used to identify the mesophase of some calamitic lanthanide mesogens as smectic A, while magnetic birefringence studies have shown a huge magnetic anisotropy for these complexes.     

with central chargeN

We study representations of the central extension of the Lie algebra of differential operators on the circle, the algebra. We obtain complete and specialized character formulas for a large class of representations, which we call primitive; these include all quasi-finite irreducible unitary representations. We show that any primitive representation with central chargeN has a canonical structure of an irreducible representation of the with the same central charge and that all irreducible representations of with central chargeN arise in this way. We also establish a duality between integral modules of and finite-dimensional irreducible modules ofgl _N , and conjecture their fusion rules.Supported by a Junior Fellowship from Harvard Society of Fellows and in part by NSF grant DMS-9205303.Supported in part by NSF grant DMS-9103792.