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An optical secure short-range communication system is presented. The mobile unit (optical smart card) of this system utilizes a retroreflector with an optical modulator, using light from the stationary unit; this mobile unit has very low power consumption and can be as small as a credit card. Such optical smart cards offer better security than RF-based solutions, yet do not require physical contact. Results from a feasibility study model are included. 相似文献
105.
Jo?l?Coulon Ilan?Thouvenin Fadi?Aldeek Lavinia?Balan Rapha?l?Schneider 《Journal of fluorescence》2010,20(2):591-597
Highly fluorescent CdTe quantum dots (QDs) stabilized by thioglycolic acid (TGA) were prepared by an aqueous solution approach
and used as fluorescent labels in detecting yeast cells. Sugars (mannose, galactose or glucose) were adsorbed on CdTe@TGA
QDs and the interaction of these nanoparticles with yeast cells was studied by fluorescence microscopy. Results obtained demonstrate
that galactose and mannose functionalized QDs associate respectively with Kluyveromyces bulgaricus and Saccharomyces cerevisiae yeast strains due to saccharide/lectin specific recognition. Glucose-functionalized CdTe QDs, which are not recognized by
cell lectins, preferentially localize in the bud scars of S. cerevisiae. 相似文献
106.
Peter‐Yong Wang Guillaume Duret Ilan Marek 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(42):15137-15141
The regio‐ and stereoselective preparation of fully substituted and stereodefined silyl enol ethers of ketones and aldehydes through an allyl‐Brook rearrangement is reported. This fast and efficient method proceeds from a mixture of E and Z isomers of easily accessible starting materials. 相似文献
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Hans-Dietrich O. F. Gronau Martin Grüttmüller Sven Hartmann Uwe Leck Volker Leck 《Designs, Codes and Cryptography》2002,27(1-2):49-91
An orthogonal double cover (ODC) is a collection of n spanning subgraphs(pages) of the complete graph K
n such that they cover every edge of the completegraph twice and the intersection of any two of them contains exactly one edge. If all the pages are isomorphic tosome graph G, we speak of an ODC by G. ODCs have been studied for almost 25 years, and existenceresults have been derived for many graph classes. We present an overview of the current state of research alongwith some new results and generalizations. As will be obvious, progress made in the last 10 years is in many waysrelated to the work of Ron Mullin. So it is natural and with pleasure that we dedicate this article to Ron, on theoccasion of his 65th birthday. 相似文献
109.
In this paper we present three different pivoting strategies for solving general tridiagonal systems of linear equations.
The first strategy resembles the classical method of Gaussian elimination with no pivoting and is stable provided a simple
and easily checkable condition is met. In the second strategy, the growth of the elements is monitored so as to ensure backward
stability in most cases. Finally, the third strategy also uses the right‐hand side vector to make pivoting decisions and is
proved to be unconditionally backward stable.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
110.
The fracture surfaces of single crystal [1 0 0] silicon specimens, fractured under three-point bending (3PB) and subjected to a high strain energy upon cracking, revealed exceptional surface perturbations, generated during the unstable propagation. While macroscopically the crack is propagating on the (1 1 1) low energy cleavage plane, microscopic examination revealed small angled deviations from and fluctuations along that plane. Furthermore, while the crack is propagating at a velocity of nearly 3000 m/s in the
direction, its velocity in the
direction is two orders of magnitude lower, with distinctive surface perturbations. The amplitude and complexity of the perturbations increase as the normal velocity vector changes its direction and magnitude. These perturbations were recorded with a profilometer and analyzed using non-linear dynamical analysis tools. This study provides an opportunity to interpret surface phenomena of one of the most general cases of fracture and to study the effect of major variables on the nature of the perturbations involved, such as the local crack tip velocity and the crystallographic orientations. It is shown that the surface perturbations are chaotic deterministic in nature and can be described by high order non-linear differential equations; the order of the equation varying with the variations of the local velocity and direction. 相似文献