Search results for "Number"

Reliability Estimation of Optimal Viscoelastic Composite Shells in Critical-Time Calculations

2003

The problem of reliability estimation for optimal viscoelastic composite shells in critical-time calculations is considered. The weight minimization of a viscoelastic composite shell, with constraints on deflections at the critical time, leads to a system deforming unstably, whose deflections grow in time with an increasing rate. A method for estimating the reliability of such shells in calculating the critical time is discussed. This time is regarded as a random variable depending on many, roughly equivalent, factors. An analysis of the reliability is carried out for different values of coefficients of variation, occurring in practice.

Criticality in the Network with Imprecise Activity Times

2002

A review of the results obtained in the area of fuzzy network analysis is presented. The main approaches to the concept of criticality in a network with fuzzy activity times are described and classified. Against the background of this review some new results, obtained by the authors recently, are presented. The paper is an extended version of the work presented in IPMU'2000 (see [8]).

Enhanced crystal stability in a binary mixture of charged colloidal spheres.

2009

We report on the phase behavior of a binary charged sphere mixture of size ratio $\ensuremath{\Gamma}=0.68$ and charge ratio $\ensuremath{\Lambda}\ensuremath{\approx}1$ as a function of composition $p$ and number density $n$. For $p=0.1--0.3$ we observe freezing at densities well below the freezing densities of the pure components. At all compositions our data indicate the formation of substitutional alloy crystals of body centered cubic structure. No indications for compound formation were observed. Rather, our findings point at the first observation of an upper azeotrope. Measurements of the crystallization kinetics reveal a combined density and composition dependence of growth velocities…

Microscopic investigations of homogeneous nucleation in charged sphere suspensions.

2005

We studied the homogeneous nucleation kinetics of an aqueous suspension of charged colloidal spheres under de-ionized conditions. Samples of equilibrium crystalline structure were shear molten and the metastable melt left to solidify after cessation of shear. At low particle number densities n, corresponding to low metastability of the melt, nucleation was monitored directly via video microscopy. We determined the nucleation rates gamma(t) by counting the number of newly appearing crystals in the observation volume per unit time. Using a suitable discrete adaptation of Avrami's [J. Chem. Phys. 7, 1003 (1939); ibid.8, 212 (1940); ibid.9, 177 (1941)] model for solidification via homogeneous n…

<title>Heavy-ion induced damage and reduction of dislocation mobility in LiF single crystals</title>

2006

Ion-induced reduction of dislocation mobility in LiF crystals irradiated with swift heavy (U) and light (Ni) ions of a specific energy of 11 MeV per nucleon at fluences between 106 and 1011 ions/cm2 was studied. The arm length of dislocation rosettes produced by indentation on (100) irradiated surface was measured. It has been found that in the case of heavy ions the threshold fluence (106 ions/cm2) for impeding of dislocation arms is about 3 orders of magnitude lower than that for light ions. The results indicate that ion-induced defect aggregates play the dominating role in the impeding of dislocations. Heavy ions, which produce defect aggregates in the track core, cause also a stronger e…

ChemInform Abstract: Analysis of Active Site Distribution in ZSM-5 Crystals by IR Microscopy.

2010

Humidity-Driven Reversible Transformation and Guest Inclusion in a Two-Dimensional Coordination Framework Tailored by Organic Polyamine Cation

2011

Using a polyamine cation tetrenH55+ (tetren = tetraethylenepentaamine), we tailored the dynamic layered material (tetrenH5)1.6{CoII(H2O)2[MIV(CN)8]}4·xH2O (1, M = W, x = 12; 2, M = Mo, x = 11.2). 1 and 2 consist of strongly corrugated two-dimensional (2D) cyano-bridged monolayers {CoII(H2O)2[MIV(CN)8]}n2n– of square grid topology stacked in an alternate manner with cationic layers of tetrenH55+ and H2O molecules. The observed single-crystal-to-single-crystal (SCSC) transformation is due to the reversible dehydration of 1 and 2 to the respective monocrystalline materials (tetrenH5)1.6{CoII[MIV(CN)8]}4 (1deh and 2deh). Structural modifications consist of the change of coordination number (C.N…

El mito de Narciso en Yo soy otro (2008) de Óscar Campo: del misterio del ser a la violencia (auto)terrorista

2017

En el presente artículo, analizaremos al detalle la refiguración posmoderna del mito clásico de Narciso en el largometraje Yo soy otro (2008), dirigido por el cineasta colombiano Óscar Campo. Según argüiremos desde una amplia perspectiva filosófica enfocada en las epistemologías contemporáneas del individuo posmetafísico, este filme propone una apropiación audaz de la trágica historia del efebo heleno que subsume las preocupaciones existenciales que determinan al sujeto contemporáneo y causan su auto-absorción individualista, su líquida impotencia, su falta de referentes trascendentales y sus pulsiones mortíferas.

«Widrige Winde»: Der Abbruch der schonischen Expedition aus der Sicht des preußischen Gesandten, des Freiherrn Friedrich Ernst von Cnyphausen

2017

There are two interpretations of Peter the Great’s motives for refusing to land on the Swedish island of Schonen in historiography: that the tsar feared unforeseen military risks and that he did not trust his allies, Denmark and Great Britain. In this article, the author attempts to analyse in a more detailed way the reasons and consequences for the mistrust in the Northern Alliance by looking at communications by Baron Friedrich Ernst von Cnyphausen, the Prussian ambassador in Copenhagen. It is shown that the Russophobic hysteria which grasped the Danish royal court in September 1716 looks completely irrational when we consider parallel attitudes in the Prussian court. Cnyphausen does not …

¿La memoria en su sitio? El museo de la Escuela de Mecánica de la Armada

2019

What should be done with a site where state terrorism was once waged? In the past few decades, many have been transformed into places of remembrance where the traumatic events that affected the whole community can be addressed. During Argentina?s last dictatorship (1976-1983), state terrorism forged a new figure, that of the ?detained-disappeared,? and the country?s detention, torture and extermination centres were the last places where these people were seen alive. That materiality, and the resignification of such sites as symbolic, is what make these locations transcendental. Perhaps, then, the question is not what needs to be represented at these sites, but what needs to be represented t…