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991.
992.
Elliot Fischer 《Cryptologia》2013,37(4):233-235
The concepts of entropy and redundancy are discussed, and calculations of the redundancy of six different languages based on available frequency data are presented. It is shown that redundancies based on digram frequencies of different languages exhibit a wide variation in value. The cryptographic implications of these calculations are discussed. 相似文献
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Highly strained In0.28Ga0.72As1−xNx/GaAs single quantum well (SQW) structures grown by molecular beam epitaxy for different N mole fractions have been investigated by photoreflectance (PR) spectroscopy at room temperature. The influence of nitrogen on the electronic structure and on the optical properties of the quantum well has been analysed. The observation of excited state transitions allowed demonstrating a type I band line-up for both heavy and light holes, for such indium and nitrogen mole fractions. All the observed optical transitions have been identified on the base of the results of the envelope function calculation including strain effects. The dependence of the optical transitions on the nitrogen content has been derived and compared with the experiment. 相似文献
994.
M. A. Yaqoob A. Winogrodzka H. R. Fischer E. R. M. Gelinck M. B. de Rooij D. J. Schipper 《Tribology Letters》2013,49(3):553-562
The pre-sliding and static friction force behaviour at asperity level between a smooth ball and a smooth flat surface at different normal loads, as well as friction behaviour during full slip has been studied. The normal load dependence of the friction force and the preliminary displacement is discussed when the mean contact pressure is kept under 100 MPa. The theoretical model to calculate the shear stress and the preliminary displacement in the contact is discussed and the experimental data were used to verify the model. The results show that for low applied normal loads the adhesion force has an influence on the friction force measurements. Furthermore, the results for the friction force and preliminary displacement show good agreement with the theoretical trends. The experiments along with the model can be used to analyse the tangential traction in the contact and the behaviour of the stick–slip area. The measurement results along with the model were used to calculate the maximum shear stress at the point of sliding for different applied normal loads. It is also shown that at low applied normal loads the shear stress is not constant as compared to relatively high applied normal loads due to the presence of adhesion force. 相似文献
995.
Mario Keplinger Dominik Kriegner Julian Stangl Thomas Ma˚rtensson Bernhard Mandl Eugen Wintersberger Günther Bauer 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(3-4):316-319
Recent investigations of core–shell nanowires using synchrotron radiation techniques deduced the average structural parameters of heterostructure core–shell nanowires. Here, we report on first results and discuss the problems arising when measuring such complex nanostructures by using nanofocusing X-ray techniques. InAs/InAsP core–shell nanowires exhibit a certain bending, the origin of which is described using finite element simulations assuming a displacement of the core, and a gradient in the chemical composition of the wire’s shell. 相似文献
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Karl‐Eugen Kurrer 《Stahlbau》2016,85(3):217-228
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