The exponential size of the search space of the resolution procedure necessitates the use of refined derivation systems, which restrict the search space. Given some fundamental refinements, further refined derivation systems can be developed by combining several fundamental refinements in a single derivation system. The manner in which combinations can be formed is necessarily restricted by the...

A program derivation is said to be polytypic if some of its parameters are data types. The repmin problem is to replace all elements of a tree of numbers by the minimum element, making only a single pass over the original tree. Here we present a polytypic derivation for that problem. The derivation has an unusual feature: when interpreted in the category of relations, the resulting program is t...

It is conventional to recognise two dimensions of paradigmatic organisation in a morphological system. The inflected forms of a lexeme L make up the inflectional paradigms of L. The new lexemes that can be defined from the root of L form what is often, by extension, termed the derivational paradigm of L. Implicit in many traditional descriptions is a third subsystem, comprising the ‘principal p...

In this paper, we give an extension of the orthogonality results to dominant operators and p-hyponormal or log-hyponormal operators, also we will generalize some commutativity results. AMS 2000 Mathematics Subject Classification. 47B47, 47A30, 47B20.

The approach of an ideal gas to equilibrium is simulated through a generalization of the Ehrenfest ball-and-box model. In the present model, the interior of each box is discretized, i.e., balls/particles live in cells whose occupation can be either multiple or single. Moreover, particles occasionally undergo random, but elastic, collisions between each other and against the container walls. I s...

the complete 3d nonlinear dynamic problem of extensible, flexible risers conveying fluid is considered. for describing the dynamics of the system, the newtonian derivation procedure is followed. the velocity field inside the pipe formulated using hydrostatic and bernoulli equations. the hydrodynamic effects of external fluids are taken into consideration through the nonlinear drag forces in var...

The classical treatment of plasmonics is insufficient at the nanometer-scale due to quantum mechanical surface phenomena. Here, an extension of the classical paradigm is reported which rigorously remedies this deficiency through the incorporation of first-principles surface response functions-the Feibelman d parameters-in general geometries. Several analytical results for the leading-order plas...

Holographic spectroscopy is highlighted as a powerful tool for the analysis of photosensitive materials with pronounced alterations of the complex permittivity over a broad range in the visible spectrum, due to the advances made both in the fields of advanced holographic media and highly tunable lasers systems. To analytically discuss consequences for in- and off-Bragg reconstruction, we revise...