The rigidity of frameworks examines points constrained by fixed distances between pairs of points, using vocabulary and linear techniques drawn from structural engineering: bars and joints, first-order rigidity and first-order flexes, and static rigidity and static self-stresses (Section 61.1. Section 61.2 describes some extended structures and their applications. Scene analysis and the dual co...

A stereological method is described for estimating the distribution of grain-boundary types in polycrystalline materials on the basis of observations from a single planar section. The grain-boundary distribution is expressed in terms of five macroscopically observable parameters that include: three parameters that describe the lattice misorientation across the boundary and two parameters that d...

Two-dimensional echocardiography was performed in two cases of distal type aorticopulmonary window. The defect of the aorticopulmonary septum could be visualised in both cases in transverse section of the great arteries using our method. We make it a rule to study three different levels of section: plane 1, where the echo of the semilunar valve of the posterior great artery is well seen; plane ...

An asymptotic analysis is carried out for the equations of free vibrations of a beam having varying curvature and cross-section. The effect of splitting the asymptotic limit for eigenvalues into two families is revealed and its connection with boundary conditions is discussed. The analysis of the properties of the asymptotic solution explains the phenomenon of transformation of mode shape with ...

A full-wave solution to the problem of electromagnetic wave focusing with two-dimensional convex dielectric lens of canonical cross-section formed by two circular arcs. Focusing effect is simulated for two polarizations of incident plane waves, TE and TM. Based on these simulations, an approximate method is proposed to reproduce the full-wave solution with reasonable accuracy for lenses of rela...

In this paper we give a simple algorithm to generate all connected rooted plane graphs with at most m edges. A “rooted” plane graph is a plane graph with one designated (directed) edge on the outer face. The algorithm uses O(m) space and generates such graphs in O(1) time per graph on average without duplications. The algorithm does not output the entire graph but the difference from the previo...

INTRODUCTION With the increase of wireless communication networks, people ask more and more information on the impact of electromagnetic field on their health. The assessment of the exposure to electromagnetic waves is the key question. Most of investigations of numerical dosimetry studies deal with a single plane wave exposure [1] but there is a lack of information on multiple waves exposure. ...

A theoretical analysis of radial wave thermoacoustic engines in cylindrical resonators is developed. Impedance and pressure translation equations are presented for open sections of the resonator and for heat exchangers. Coupled first-order differential equations are given for pressure and impedance in the temperature gradient supporting engine section ~stack!. These quantities are used to calcu...

A novel 30-item multiple choice psychometric test was developed to measure individual differences in a spatial visualization task that involves identifying the cross section that results from the intersection of a cutting plane and a geometric solid. An initial study with 59 participants established the internal reliability and external validity of the test. Items in the test varied in complexi...